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Sample records for kenitra maroc particules

  1. Atmospheric particulate pollution in Kenitra (Morocco)

    International Nuclear Information System (INIS)

    Zghaid, Mustapha; Noack, Yves; Boukla, Moussa; Benyaich, Fouad

    2009-01-01

    Cities of Morocco are exposed to a high atmospheric particulate pollution due to automobile traffic, industrialization, but also to soil dusts (in relation with aridity and desert proximity). Monitoring networks and data about air pollution still rare. The present study is a preliminary work about particulate and heavy metals pollution in Kenitra city. Aerosols had been collected with a PM10 sampler (Partisol), a dichotomous sampler (P M2.5 and P M2.5-10 fractions) and stacked filter unit (Gent type) with a fine fraction (below 2.5 um) and a coarse fraction. In summer, the average PM10 concentration is near 80 u g/N m 3 , above the EEC rule and OMS recommendations, but similar to some other african towns. The ratio P M2.5/PM 10 is low (below 0.5), with seasonal variation in relation with meteorology. The lead and nickel concentrations are also very low, in relation with the use of leaded gasoline and the oldness of many vehicles. This preliminary work reveals high levels of pollution (especially PM10, Pb and Ni) in the town of Kenitra. The major sources are traffic, soil dusts and resuspension of deposited particles. It is necessary to develop monitoring network and sanitary and and environmental impact studies in these cities [fr

  2. Evaluation of airborne particulate matter pollution in Kenitra City, Morocco

    Directory of Open Access Journals (Sweden)

    Abdelfettah Benchrif

    2013-04-01

    Full Text Available Two size fractions of atmospheric particulate matter < 2.5 µm and 2.5-10 µm were collected in Kenitra City from February 2007 to February 2008. The sampling was done using a Gent Stacked sampler on nuclepore polycarbonate filters and the collected filters were analyzed using Total Reflection X-Ray Fluorescence (TXRF and Atomic Absorption Spectroscopy (AAS. The particulate matter trends show higher concentrations during the summer as compared to other seasons. The highest concentrations were obtained for Ca in coarse particles and Fe for fine particles. However, the lowest concentrations were observed for Cd in both particulate sizes. The principal component analysis (PCA based on multivariate study enabled the identification of soil, road dust and traffic emissions as common sources for coarse and fine particles.

  3. Maroc

    African Journals Online (AJOL)

    hadji

    ... en eaux abondantes, font de la province de Sidi Slimane, une zone agricole de première importance. Cette province constitue un collecteur naturel des eaux de surface. ..... cycles biologiques des moustiques (Diptera, Culicidae) au Maroc.

  4. Evaluation of atmospheric pollution in Kenitra city (MOROCCO) (Particles and Metals)

    International Nuclear Information System (INIS)

    Zghaid, M.; Noack, Y.; Tahiri, M.; Zahry, F.; Bounakhla, M.; Benyaich, F

    2008-01-01

    Full text: All Recent epidemiological studies show that air pollution in general and especially particulate pollution have a strong influence on human health, particularly on the respiratory and cardio-vascular systems, but also affect the developing fetus. Like developed countries, countries under development are subject to significant air pollution both urban and industrial. The car park is often old, sometimes uncontrolled industrialization, the regulations of atmospheric emissions are infancy and the network monitoring rare. The aim of this work is to focus on the problem of particulate air pollution in Kenitra (50 km north of Rabat, Morocco) by characterizing the pollution in both quantity and quality, to assess the impact potential health and provide decision makers with reliable data. Initial results show that the OMS recommendations, along with European standards on sulfur dioxide as well as PM10 are largely outdated (80 ug / Nm 3 instead of 40 in average). This is also the case for some metals: Lead concentrations are approximately ten times greater than those encountered in urban sites in Europe; nickel is fifteen times higher than the European standard. The metals are mainly present in the thin fraction (particles below 2.5 um). The low proportion of thin particles in the total particles, show the influence of resuspension events and other natural inputs from arid or desert. The SO2 average concentrations are also quite important (60 ug / m 3 ). The concentrations near the site are much higher than those that can be measured on similar sites in Europe. It is more than probable that in this city, the health impacts are not negligible. We will look to continue this work in three aspects: Spatial distribution of particulate pollution in Kenitra; The health impact of air pollution in Kenitra; Cyto-and geno-toxicity of airborne particles in Kenitra [fr

  5. Risk Factors of Anaemia Among Rural School Children in Kenitra ...

    African Journals Online (AJOL)

    Objective: To determine the prevalence of anaemia and factors associated with iron deficiency among school children in rural Kenitra, Morocco. Methods: 295 students between 6 and 16 years old composed the study group. The level of haemoglobin was measured in a group of 295 school children. The iron status was ...

  6. Parasitic helminth load in urban waste-water of Kenitra City, Morocco

    African Journals Online (AJOL)

    Waste-waters of Kenitra City are rejected without any preliminary treatment in the receiving medium (Sebou River, Fouarat Lake). A small fraction is used to irrigate crops in the peri-urban area of Kenitra City. The parasitological characterization revealed an average parasitic helminth egg concentration of 25.07 per liter ...

  7. Le marécage de Fouwarate (Kenitra, Maroc) : site de conservation d ...

    African Journals Online (AJOL)

    ouest de la plaine littorale du Gharb, sur le cours de l'oued Fouwarate, petit affluent du cours terminal de l'oued Sebou. Cette zone humide est l'un des derniers représentant d'un complexe de marécages qui occupait ladite plaine et qui offrait ...

  8. Major sickle cell syndromes in children in Kenitra, Morocco

    Directory of Open Access Journals (Sweden)

    Khalid Hafiani

    2017-11-01

    Full Text Available Objective: To highlight the epidemiological characteristics and plot the current mapping of the sickle cell syndromes in children under 15 years old. Methods: A descriptive study was conducted on children with sickle cell disease over a period of 4 years (from January 2011 to December 2015 at the Pediatric Department at El Idrissi Regional Hospital Center in Kenitra, Morocco. Results: The mean age of patients was (8.56 ± 3.97 years and the age group 6–15 years was the most affected. The male gender was the most dominant with 60.94% of cases versus 30.06% for females. The homozygous form SS was the most frequently identified (81.25% of cases while the heterozygous form SC was rarely detected (2.08%. Conclusions: Sickle cell anemia remains a reality in Morocco and may not be perfectly understood yet by health professionals. A screening policy and a sustainable management program can prevent hemoglobinopathies in the studied region. An action plan must be implemented at national level to improve the quality of management of main sickle cell syndromes.

  9. (l.) Medik du Maroc

    African Journals Online (AJOL)

    PR BOKO

    Résumé. Dipcadi serotinum (L.) Medik, est une plante de la famille des Hyacinthaceae, elle est largement utilisée comme réchauffant et aussi pour combattre la jaunisse. Cette plante trouve une large utilisation par la population de la région côtière du Maroc. À notre connaissance l'huile essentielle de cette espèce n'a ...

  10. Lac dayet Aoua (Maroc)

    African Journals Online (AJOL)

    Saad

    F.S.T. Fès - Sais, Université Sidi Mohammed Abdallah Fès, B.P. 2202, Maroc. 2Laboratoire des ... d'étude en complément de la composition phytoplanctonique et des analyses de la physico-chimie des eaux à l'entrée, au ... L'analyse des paramètres physico-chimiques, au point central du lac, a montré que l'eau du lac.

  11. La sociologie au Maroc

    Directory of Open Access Journals (Sweden)

    Rahma Bourqia

    2011-10-01

    Full Text Available Sans prétendre à l’exhaustivité, l’article donne un aperçu de la genèse et du développement de la sociologie, produite par les sociologues marocains, depuis l’indépendance du Maroc et jusqu’en 2006. Il faire ressortir les grandes étapes, les grands thèmes de recherche et éventuellement les paradigmes théoriques qui les orientent, tout en tenant compte du caractère flou des frontières entre la sociologie et d’autres disciplines, notamment l’anthropologie.Sociology in Morocco. Major steps and thematic milestonesWhile not pretending to thoroughness, this article gives an overview of the origins and the development of the sociology produce by Moroccan sociologists, from Morocco’s independence until 2006. It will highlight its major steps, the main research themes, and eventually theoretical paradigms that orient them. It will also take into account the blurring of the boundaries between sociology and other fields, especially anthropology.La sociología en Marruecos. Principales etapas y jalones temáticosSin pretender ser exhaustivo, este artículo permite atisbar la génesis y el desarrollo de la sociología producida por los sociólogos marroquíes, desde la independencia hasta 2006. Se subrayan las  principales etapas, los principales temas de investigación y eventualmente los paradigmas teóricos que los orientan teniendo en cuenta la imprecisión de las fronteras entre la sociología y las otras materias particularmente la antropología.

  12. Prevalence of Iron Deficiency Anaemia Among School Children in Kenitra, Northwest of Morocco.

    Science.gov (United States)

    Achouri, I; Aboussaleh, Y; Sbaibi, R; Ahami, A; El Hioui, M

    2015-04-01

    Iron deficiency anaemia is an important health problem in Morocco. This study was conducted to estimate the prevalence of anaemia among school children in Kenitra. The sample represents school children of all educational levels and age ranged between 6-15 years. The level of hemoglobin, haematocrit, mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration was measured in a group of 271 school children. The seric iron was assessed and anaemia was defined when hemoglobin education of the mother and anaemia in children (p = 0.004) but not with the family income. It is concluded that improving the economic status of the family, women education and health education about balanced animal and plant food consumption are recommended strategies to reduce the burden of anaemia.

  13. L’olivier au Maroc

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    El Mouhtadi Issam

    2014-03-01

    Full Text Available L’olivier est une culture traditionnelle sur le pourtour de la Méditerranée. Il est donc naturel de trouver cet arbre au Maroc où il est présent depuis des siècles. Cultivé surtout traditionnellement jusqu’à ses dernières années, il fait l’objet maintenant d’un plan de valorisation très ambitieux pour non seulement garder le Royaume à son niveau actuel (2e producteur mondial pour l’olive de conserve et 6e pour l’huile d’olive mais pour conquérir de nouveaux marchés au niveau mondial et profiter ainsi de l’engouement que connaît cette huile reconnue pour ses bienfaits. Le plan national « Maroc Vert » permet ainsi, grâce à des subventions conséquentes, non seulement de renouveler les vergers existant avec la variété traditionnelle picholine du Maroc, mais également la plantation de nouvelles variétés en super-intensif dans le but d’industrialiser au maximum de nouveaux vergers. Il en est de même pour la transformation des olives en huile de bonne qualité avec la mise en place d’unités de trituration modernes qui doivent supplanter à terme la multitude de « maâsra » et réduire ainsi l’impact environnemental dû aux margines. L’olive ne sera plus dans l’avenir que représentée par son huile et ses formes comestibles, mais les résidus de son extraction seront valorisés soit sous forme de combustible élaboré pour le grignon, soit sous forme d’une base de chimie verte pour les sous-produits du raffinage. D’autres applications sont actuellement à l’étude, car le Maroc à compris, comme tous les autres grands pays producteurs, que l’olive était un nouveau gisement de richesses.

  14. Fès, la cybercapitale du Maroc

    International Development Research Centre (IDRC) Digital Library (Canada)

    Fès, la cybercapitale du Maroc. La ville de Fès est devenue un modèle primé en matière de mise en œuvre efficace des technologies de l'information et de la communication (TIC) dans les services publics d'un pays africain. ès, au Maroc. Dans une pièce renfermée datant des années 1950, des centaines de documents.

  15. Risk factors of anaemia among rural school children in Kenitra, Morocco.

    Science.gov (United States)

    El Hioui, M; Ahami, A O T; Aboussaleh, Y; Rusinek, S; Dik, K; Soualem, A; Azzaoui, F-Z; Loutfi, H; Elqaj, M

    2008-08-01

    To determine the prevalence of anaemia and factors associated with iron deficiency among school children in rural Kenitra, Morocco. 295 students between 6 and 16 years old composed the study group. The level of haemoglobin was measured in a group of 295 school children. The iron status was determined by ferritin level in serum, and anaemia was defined when haemoglobin educational status of the parents. The mean haemoglobin concentration was 12.4 g/dl in boys and 12.5 g/dl in girls, whereas the mean ferritin level was 26.7 microg/l in boys and 27.9 microg/l in girls. The overall prevalence of anaemia in the studied population was 12.2% and iron deficiency was 20.4%. There was a significant relationship between education of the mother and anaemia in children (p= 0.01). Serum ferritin (SF), serum iron concentrations and mean corpuscular volume (MCV) were significantly correlated with haemoglobin by multiple regression analysis. However, using logistic regression analysis, the results showed that anaemia was not significantly associated with gender, parents' employment and monthly family income. Anaemia remains a common problem in the young children particularly the primary education school boys of the households of low income. The results suggest also, that iron deficiency is an important determinant of anaemia in this population; however, whole anaemia cannot be solely explained by iron deficiency. Further studies are needed to consider micronutrients status and exposure to environmental pollutants.

  16. MAROC, a generic photomultiplier readout chip

    International Nuclear Information System (INIS)

    Blin, S; Barrillon, P; La Taille, C de

    2010-01-01

    The MAROC ASICs family is dedicated to the readout of 64-channel Multi Anode PMT and similar detectors. Its main roles are to correct the gain spread of MAPMT channels thanks to an individual variable gain preamplifier and to discriminate the input signals (from 50fC i.e 1/3 photo-electron) in order to produce 64 trigger outputs. A multiplexed analog charge output is also available with a dynamic range around 10 pe ( ∼ 1.6 pC) and a 12 bit Wilkinson ADC is embedded. Three versions of this chip have been submitted. MAROC 2 is the production version for the ATLAS luminometer and MAROC3 is a version with lower dissipation and significant improvements concerning the charge (30 pe: ∼ 5 pC) and trigger (discrimination from 10fC). This third version showed very good characteristics that are presented here.

  17. MAROC, a generic photomultiplier readout chip

    Energy Technology Data Exchange (ETDEWEB)

    Blin, S; Barrillon, P; La Taille, C de, E-mail: blin@lal.in2p3.f [CNRS/IN2p3/LAL-OMEGA, Universite Paris Sud, Bat.200, 91898 Orsay (France)

    2010-12-15

    The MAROC ASICs family is dedicated to the readout of 64-channel Multi Anode PMT and similar detectors. Its main roles are to correct the gain spread of MAPMT channels thanks to an individual variable gain preamplifier and to discriminate the input signals (from 50fC i.e 1/3 photo-electron) in order to produce 64 trigger outputs. A multiplexed analog charge output is also available with a dynamic range around 10 pe ( {approx} 1.6 pC) and a 12 bit Wilkinson ADC is embedded. Three versions of this chip have been submitted. MAROC 2 is the production version for the ATLAS luminometer and MAROC3 is a version with lower dissipation and significant improvements concerning the charge (30 pe: {approx} 5 pC) and trigger (discrimination from 10fC). This third version showed very good characteristics that are presented here.

  18. MAROC, a generic photomultiplier readout chip

    Science.gov (United States)

    Blin, S.; Barrillon, P.; de La Taille, C.

    2010-12-01

    The MAROC ASICs family is dedicated to the readout of 64-channel Multi Anode PMT and similar detectors. Its main roles are to correct the gain spread of MAPMT channels thanks to an individual variable gain preamplifier and to discriminate the input signals (from 50fC i.e 1/3 photo-electron) in order to produce 64 trigger outputs. A multiplexed analog charge output is also available with a dynamic range around 10 pe ( ~ 1.6 pC) and a 12 bit Wilkinson ADC is embedded. Three versions of this chip have been submitted. MAROC 2 is the production version for the ATLAS luminometer and MAROC3 is a version with lower dissipation and significant improvements concerning the charge (30 pe: ~ 5 pC) and trigger (discrimination from 10fC). This third version showed very good characteristics that are presented here.

  19. (Maroc).

    African Journals Online (AJOL)

    AKA Boko

    Study of the physico-chimical and bacteriological quality in M'nasra's groundwater (Morocco). The aim of this study was to evaluate the impact of the intensification of agricultural activity and discharges untreated wastewater on the physicochimical and bacteriological quality in M'nasra's groundwater. The results show the ...

  20. Maroc

    African Journals Online (AJOL)

    LDSE

    The objective of this work is the agronomic evaluation of soil quality under vine and wheat in the ... Keywords : Mohammedia-Benslimane, fertility, total organic carbon, nitrogen, phosphorus and potassium. 1. ... selon le gradient nord-sud.

  1. Inventaire des champignons ectomycorhiziens du Maroc

    African Journals Online (AJOL)

    SARAH

    31 juil. 2014 ... RÉSUMÉ. Objectif : Le travail présenté ici a pour objectif de dresser, à partir de la bibliographie, l'inventaire des espèces ectomycorhiziennes du Maroc. Méthodologie et résultats : Les données sur les champignons, recueillies à partir de différents travaux publiés nous ont permis de réaliser un premier ...

  2. Maroc-hop: music and youth identities in the Netherlands

    NARCIS (Netherlands)

    Gazzah, M.; Herrera, L.; Bayat, A.

    2010-01-01

    Two musical forms highly popular among youths of Moroccan origin in the Netherlands—Maroc-hop and Shaabi—permit youths to express specific and multiple identities in local contexts. Shaabi, a popular form of Moroccan folk music used to be found mainly in the private setting of family celebrations,

  3. Contribution à la connaissance des micromycètes du Maroc. Cas ...

    African Journals Online (AJOL)

    Contribution à la connaissance des micromycètes du Maroc. Cas des ... et qualitative des micromycètes d'origine terrestre de la région de Rabat (Maroc). ... elles ont été entraînées dans le milieu aquatique par différents moyens de transport.

  4. Maroc : La valeur de l'eau | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    13 mai 2016 ... Le Maroc, au nord de l'Afrique, est un territoire en partie aride, où les pluies sont rares, mais où l'agriculture prospère malgré tout. Les changements climatiques ont cependant eu ici des effets majeurs dans les dernières années. Les précipitations ont diminué de 20 % et les vagues de chaleur ou de froid ...

  5. Gestion des parcours dans la province de Rhamna (Maroc) | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Au Maroc, les parcours font l'objet d'une grave dégradation, et cela a suscité des interventions publiques visant à réduire les pressions exercées sur les ressources naturelles et à favoriser une gestion durable. Dans la province de Rhamna, où l'on pratique depuis des générations la transhumance, les interventions n'ont ...

  6. Le marché sociolinguistique contemporain du Maroc

    NARCIS (Netherlands)

    de Ruiter, A.C.J.; Ziamari, Karima

    2014-01-01

    Au Maroc, les langues sont l’objet des polémiques les plus passionnées. Ce livre s’inscrit ainsi dans la continuité du débat concernant les politiques linguistiques adoptées et met à jour les évolutions récentes du marché sociolinguistique après l’adoption de la nouvelle constitution, approuvée par

  7. Explotación de canteras en la costa de Kenitra y su área de influencia: Estudio de impacto ambiental

    Directory of Open Access Journals (Sweden)

    Hicham Khabali

    2013-12-01

    Full Text Available La extracción de materiales de construcción, principalmente aquellos que se utilizan para fabricar los conglomerados utilizados en ingeniería civil, construcción y obras públicas, es una práctica generalizada en la región de Kenitra, y se concentran principalmente a lo largo del cordón dunar entre Kenitra y Moulay Bousselham. Esta industria extractiva se caracteriza por explotar una materia prima poco o simplemente no renovable. Por otra parte, su preservación requiere indispensablemente un conocimiento al detalle de los diversos yacimientos en explotación así como aquellos potencialmente explotables, y sus grados de sensibilidad frente a un uso inapropiado. Se requiere un estudio a fondo de los yacimientos existentes e identificar sus límites ambientales para así definir unas directrices de uso racional y económico de los conglomerados. El desarrollo de la región norte y la ejecución de proyectos claves en el desarrollo y la gestión de infraestructuras y superestructuras, como son la circunvalación del mediterráneo, el puerto de Tánger-Med, la autovía de Tánger-Larache, la construcción de la ciudad de Al Hoceima y de zonas turísticas como la que podemos encontrar en la ciudad de Saaidia, han resultado en una mayor demanda de materiales de construcción, que sigue aumentando, a nivel de toda la región. Esta necesidad es sin duda importante, pero al mismo tiempo cada vez mayor, y puede resultar en una explotación abusiva, no conforme a la legislación vigente. Esta actividad minera, por la ausencia de instrumentos apropiados para el seguimiento y un plan de gestión que tenga en consideración los recursos disponibles y los ecosistemas y entornos naturales sensibles, puede ser la causa de perjuicios que pueden afectar tanto al medio natural como al sector socio-económico. Este estudio consiste en la realización de la Evaluación de Impacto Ambiental (EIA de las canteras en la región de Kenitra. Su propósito es

  8. Calcifications valvulaires chez l'hémodialysé au Maroc | Faqih | Pan ...

    African Journals Online (AJOL)

    Calcifications valvulaires chez l'hémodialysé au Maroc. Samia Ait Faqih, Béfa Noto-Kadou-Kaza, Lalla Meryam Abouamrane, Naoufal Mtiou, Selma El Khaya, Mohamed Zamd, Ghislaine Medkouri, Mohamed Gharbi Bengahanem, Benyounes Ramdani ...

  9. Maroc | CRDI - Centre de recherches pour le développement ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Appliquer à grande échelle la chaîne de valeur du quinoa pour améliorer la sécurité alimentaire dans les communautés pauvres/rurales du Maroc. Au Maroc, la pauvreté rurale demeure un problème et l'on s'attend à ce qu'il s'accentue. Voir davantageAppliquer à grande échelle la chaîne de valeur du quinoa pour ...

  10. S'adapter à une nouvelle réalité environnementale au Maroc | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    environnement ne cessent d'avoir une incidence sur le Maroc, un projet financé par le CRDI aide les populations à innover afin de survivre. Cet article fait partie d'une série de reportages sur des projets innovants mis en oeuvre ...

  11. Étude de quelques Pucciniales liés aux plantes cultivées au Maroc

    African Journals Online (AJOL)

    SARAH

    2013-12-30

    Dec 30, 2013 ... Cette rouille n'a jamais été signalée auparavant sur Mentha viridis (hôte nouvel) dans le. Maroc. Au Maroc, Puccinia menthae Pers. (1801) a été rencontrée sur Mentha rotundifolia au lieu frais près d'Idni sur la route du Tizi n'Test (Haut Atlas), Satureja calamintha subsp. ascendes dans la pelouse au bord.

  12. CHR AL IDRISSI OF KENITRA

    African Journals Online (AJOL)

    lanez

    31 déc. 2014 ... prescription médicale, dans un objectif de diagnostic, dépistage, ... L'activité de cet emploi/métier s'exerce au sein de laboratoires (analyses médicales, recherche, ... Techniques de prélèvement biologique. Réaliser ... albicans, Pseudomonas, Syphilis, Les virus d'hépatite et le VIH) dans des prélèvements.

  13. Quels usages de la bibliotheque au Maroc 

    Directory of Open Access Journals (Sweden)

    Anouk Cohen

    2008-10-01

    Full Text Available Officine de l’âme et de l’esprit, la bibliothèque représente ce lieu où se forme un patrimoine, individuel ou collectif, et où s’élabore une construction, personnelle ou non, référant à une histoire, elle-même relative à une mémoire propre. Afin de cerner ce qu’il en est au Maroc, nous interrogerons, sous un angle ethnologique, le rapport des lecteurs à leur bibliothèque, qu’elle soit publique ou privée, afin non seulement de comprendre quels sont les livres appelés à constituer le patrimoine dont elle sera le dépositaire : à faire patrimoine, mais également cerner les représentations qui lui sont attachées, la mémoire à laquelle elle réfère, les usages qui en découlent, et le rôle qui lui est attribué. Alors que la bibliothèque publique fait l’objet d’usages limités et strictement fonctionnels de la part de ses usagers, la bibliothèque privée donne lieu à davantage d’appropriations personnelles. Nous tenterons de comprendre pourquoi les pratiques attachées à la bibliothèque sont davantage, voire essentiellement, retranchées dans le domaine privé, en interrogeant les usages réels, c'est-à-dire privés, de la bibliothèque. On observera que les bibliothèques privées sont dépositaires d’un patrimoine traditionnel tirant son essence de l’histoire arabe et d’une mémoire de l’Antiquité. Un patrimoine, nous le verrons, davantage véhiculé par l’esthétique propre aux ouvrages qui le portent que par leur contenu. A cette fonction esthétique de la bibliothèque s’ajoute un rôle distinctif, chaque individu en effet, au travers de sa bibliothèque racontant son histoire relative à une mémoire singulière.

  14. Cartographie et contrôle au Maroc sous le Protectorat espagnol (1912-1956

    Directory of Open Access Journals (Sweden)

    José Luis Villanova

    2010-06-01

    Full Text Available La principale fonction des interventores (contrôleurs du Protectorat espagnol au Maroc entre 1912 et 1956 a consisté à surveiller l’action des autorités tribales marocaines pour asseoir la présence coloniale. Cependant, le Haut-Commissariat d’Espagne au Maroc leur a souvent demandé de préparer des rapports d’ordre économique, social ou à finalité militaire sur les tribus, généralement mal connues de l’autorité coloniale. Ces documents contiennent des cartes de qualité variée qui ont pu constituer un instrument précieux de contrôle et, dans certains cas, un outil de propagande au service de l’action coloniale espagnole.

  15. Sélection de quelques plantes médicinales du Zerhoun (Maroc ...

    African Journals Online (AJOL)

    SARAH

    14 mars 2014 ... RÉSUMÉ. Objectif : Évaluer in vitro l'activité antibactérienne de deux extraits de feuilles de 14 plantes médicinales du massif de Zerhoun (Maroc central) (l'extrait aqueux et l'extrait éthanolique) sur la croissance de six souches de. Pseudomonas aeruginosa. Méthodologies et Résultats : La méthode de ...

  16. Maroc : tous les projets | Page 4 | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Du 7 au 10 février 2005, les représentants de cinq pays d'Afrique francophone (le Cameroun, le Maroc, le Niger, le Sénégal et la République démocratique du Congo - RDC) se sont réunis pour s'interroger sur les voies et moyens de dynamiser l'appropriation des technologies d'information et de la communication (TIC).

  17. 357 Datation des carbonates impurs au Maroc à l'aide de la ...

    African Journals Online (AJOL)

    youness

    Datation des carbonates impurs au Maroc à l'aide de la méthode de déséquilibre radioactif 230Th/234U. A. Choukri1, S. Semghouli1, O. Hakam1, M. Moheidine3 et M. Laatiris4. 1Laboratoire de Physique de la Matière et Rayonnement, Equipe de. Physique et Techniques Nucléaires, Faculté des Sciences, P.B 133,. 14000 ...

  18. Sénégal-Maroc : usages et mésusages de la circulation des ...

    African Journals Online (AJOL)

    24 juin 2015 ... la coopération subsaharienne s'inscrit donc dans une politique d'ensemble ... géopolitique et sa capacité de captage de ressources internationales. Ainsi, la ... mesures administratives, des énoncés scientifiques, des propos ..... faire valoir ce qu'ils considèrent comme leurs droits à vivre au Maroc à y.

  19. Problematique de la gestion des eaux souterraines au Maroc

    Directory of Open Access Journals (Sweden)

    Mennani, A.

    2002-08-01

    Full Text Available Maroc a toujours fait du développent du secteur de l'eau une priorité et un choix stratégique. Ce secteur qui constitue un des principaux leviers du développement économique et social, se trouve confronté a deux défis essentiels: - L'épuisement des ressources en eau en rapport avec l'accroissement de la demande en eau tous usages confondus, avec une tendance a la pénurie absolue d'ici 2025. - La dégradation des ressources en eau qui subissent différentes formes de pollution. La rareté des ressources en eau, et la forte irrégularité aussi bien spatiale, que temporelle, qui caractérisent le contexte marocain, ont conditionné les choix des pouvoirs publics 2 adopter une stratégie globale dont les résultats ont prouvé son efficacité particulikrement durant les périodes de sécheresse consécutives. Cette stratégie tout azimuts a concerné aussi bien le plan législatif et réglementaire, que le plan de la mobilisation et de la protection des ressources en eau. Les études de pldcation entreprises ont montré que les ressources en eau conventionnelles seront saturées au niveau de la majorité de bassins a l'horizon 2020, et que ces déficits prévus risquent d'gtre aggravés dans le cas de conjonction avec des périodes de sécheresse. La politique de mobilisation et de protection des ressources en eau, en particulier souterraine dont le potentiel mobilisable est de l'ordre de 4 milliards de m3 sur un total de 20 milliards, nécessite une gestion participative ainsi que le recours a de nouvelles approches et technologies pour compléter les méthodes conventionnelles utilisées jusqu'a présent.Marruecos siempre ha considerado prioritario y estratégico el desarrollo del sector del agua. Este sector, que constituye una de las principales palancas del desarrollo económico y social, se enfrenta a dos desafíos principales: - La disminución de los recursos hídricos en relación con el aumento de la demanda para todo tipo de

  20. Développement de l'irrigation et partenariats public-privé au Maroc ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le modèle sera fondé sur une étude comparative de deux modes d'irrigation dans le ... à un débat plus large sur le développement du marché de l'eau au Maroc. ... Le Centre de recherches pour le développement international est heureux ... Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de ...

  1. Société civile et islamisme en Iraq et au Maroc | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Par son dynamisme, la société civile du Maroc s'est approprié avec les années un rôle traditionnellement dévolu aux institutions de l'État, soit offrir des services sociaux dans les secteurs de la santé, de l'éducation et du logement. Particulièrement efficaces à ce chapitre, les organismes islamiques de la société civile ont su ...

  2. Etude s?ro-?pid?miologique de la leishmaniose canine au centre du Maroc

    OpenAIRE

    Fellah, Hajiba; Doughmi, Oursula; Maniar, Sa?d; Lalami, Abdelhakim El Ouali

    2014-01-01

    Dans le monde, la leishmaniose visc?rale humaine est connue pour avoir comme principale source d'infection les Canid?s domestiques et sauvages. Au centre du Maroc, les donn?es ?pid?miologiques, cliniques et parasitologiques sur la leishmaniose canine, sont quasiment inexistantes. Ce travail traite une ?tude prospective au cours de laquelle 61 s?rums canins ont ?t? analys?s par un test rapide et par l'immunofluorescence indirecte. La sensibilit? du test rapide par rapport ? celle de l'immunofl...

  3. Faut-il réformer la caisse de compensation au Maroc ?

    OpenAIRE

    Tarbalouti, Mr

    2014-01-01

    Faut-il réformer la caisse de compensation au Maroc? Par Essaid Tarbalouti Version, Mars 2014 The debate on the efficiency of the subsidy of the prices of foodstuffs granted by the policy of compensation and his reform are deeply livened up between the government and the opposition in terms of its cost and its ineffectiveness. This debate concentrate on the social earnings to replace this mechanism of assistant by the granting of a minimum income to the poor people. We...

  4. Les défis de l’intelligence économique au Maroc

    Directory of Open Access Journals (Sweden)

    Boujemâa Achchab

    2013-12-01

    Full Text Available L’intelligence économique s’est imposée dans plusieurs pays du monde comme moyens puissant du développement de la compétitivité et de la performance. Elle vise l’alignement de la stratégie aux exigences de l’environnement. Il est devenu clair que pour toute organisation, identifier et exploiter l’information pertinente relative à son environnement spécifique relève du défi permanent. De ce fait, notre communication vise de répondre à la problématique suivante: Quels sont les défis de l’intelligence économique au Maroc? Une classification des défis sera présentée, ainsi que des pistes de réflexions pour les dépasser.

  5. Profil des diabétiques en hémodialyse chronique: étude multicentrique au Maroc

    OpenAIRE

    Kabbali, Nadia; Mikou, Souad; El Pardiya, Nada Tazi; El Bardai, Ghita; Arrayhani, Mohamed; Houssaini, Tarik Sqalli

    2014-01-01

    Introduction Le diabète représente la première cause de mortalité par insuffisance rénale au Maroc. Sa prévalence selon l'Enquête Nationale sur la Population et la Santé Familiale de 2011 est de 3,3% [1]. Le but de ce travail est de déterminer la prévalence et d’étudier le profil clinique des diabétiques en hémodialyse chronique au Maroc. Méthodes Il s'agit d'une étude transversale multicentrique incluant 2066 hémodialysés chroniques dans les 39 centres d'hémodialyse de quatre régions marocai...

  6. Airborne particulate discriminator

    Science.gov (United States)

    Creek, Kathryn Louise [San Diego, CA; Castro, Alonso [Santa Fe, NM; Gray, Perry Clayton [Los Alamos, NM

    2009-08-11

    A method and apparatus for rapid and accurate detection and discrimination of biological, radiological, and chemical particles in air. A suspect aerosol of the target particulates is treated with a taggant aerosol of ultrafine particulates. Coagulation of the taggant and target particles causes a change in fluorescent properties of the cloud, providing an indication of the presence of the target.

  7. L'huile d'argan du Maroc, première IGP africaine | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    8 oct. 2010 ... La Commission nationale des signes distinctifs d'origine et de qualité (CNSDOQ) du Maroc a attribué l'appellation IGP (indication géographique protégée) à l'huile d'argan, appréciée depuis longtemps pour ses vertus nutritives, cosmétiques et médicinales. Le roi Mohammed VI a remis au groupe ...

  8. Le Plan Maroc Vert et l’autosuffisance alimentaire en produits de base à l’horizon 2020

    Directory of Open Access Journals (Sweden)

    Souleymane Nouréini Sayouti

    2015-10-01

    Full Text Available La présente étude a pour objectif d’analyser les effets probables de la nouvelle stratégie agricole marocaine (le Plan Maroc Vert sur la situation alimentaire (dépendance ou autosuffisance alimentaire du Maroc à l’horizon 2020. Elle a concerné sept produits de base indispensables à la diète marocaine à savoir : le lait, le sucre, l’huile de table, la viande rouge, la viande blanche, le blé tendre et le blé dur. L’approche méthodologique utilisée consiste à prévoir la demande alimentaire du pays, pour l’horizon 2020, en ces denrées. La méthode utilisée pour la prévision de la demande prend en compte la taille de la population, l’élasticité-revenu et l’évolution du niveau de revenu par habitant. La demande projetée est comparée aux niveaux de production prévus par le Plan Maroc Vert pour le même horizon. Ces prévisions ont révélé que malgré les efforts d’augmentation des niveaux de production prévus dans le cadre du Plan Maroc Vert, le Maroc ne pourrait pas atteindre une autosuffisance alimentaire pour le blé tendre, le blé dur, le sucre et les huiles de table à l’horizon 2020. Par contre, cette autosuffisance serait possible pour le lait, les viandes rouges et les viandes blanches. Ces résultats montrent que les décideurs politiques devraient mieux orienter l’intervention de l’Etat pour améliorer l’offre du pays pour le premier groupe des produits. En revanche, les possibilités d’exportation devraient être encouragées pour le deuxième groupe de produits notamment vers les marchés émergents tels que ceux de l’Afrique Subsaharienne.

  9. Enquete sur les aspects toxicologiques de la phytotherapie utilisee par un herboriste à Fes, Maroc

    Science.gov (United States)

    Zeggwagh, Ali Amine; Lahlou, Younes; Bousliman, Yassir

    2013-01-01

    Introduction Dans le but d'étudier l'aspect toxicologique des plantes médicinales utilisées en médecine traditionnelle, une étude ethnobotanique a été réalisée à la ville de Fès au centre du Maroc. Méthodes Ont été inclus dans l'étude tous les patients ayant bénéficié d'une prescription par l'herboriste de plantes à visée thérapeutique. La discussion de nos résultats s'est faite sur la base d'une revue de la littérature avec identification des principales plantes toxiques utilisées en phytothérapie au Maroc. L'approche bibliographique a permis de compléter les informations. Résultats L'âge moyen des patients traités par des plantes (38 femmes, 32 hommes) était de 35 ± 18 ans. L'enquête ethnobotanique à révélé que la majorité des plantes médicinales étaient utilisées contre les affections urinaires (21%), suivi des maladies de l'appareil digestif (19.6%) et des maladies rhumatologiques (18.2%). Le nombre de plantes prescrits par l'herboriste a été de 53 dont 5 sont potentiellement toxiques. L'identification taxonomique des plantes prescrites a recensé 30 familles dont les plus représentées sont les Lamiaceae (23.33%), les Apiaceae (13,33%) et les Asteraceae (10%). La prescription des plantes considérées comme toxiques a concerné 7,1% des consultants traités par les plantes médicinales. Aucune complication inhérente aux plantes prescrites n'a été déplorée. Conclusion Malgré les résultats encourageants de notre enquête sur le compte de la phytothérapie, la pratique de la phytothérapie est laissée à la vulgarisation et à l'oubli scientifique, législatif et universitaire. PMID:23734270

  10. SiPM-MAROC gamma-camera prototype with monolithic NaI(Tl) scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Philippov, Dmitry; Ilyin, Andrey; Belyaev, Vladimir; Popova, Elan [National Research Nuclear University, Moscow Engineering Physics Institute (Russian Federation); Buzhan, Pavel; Stifutkin, Alexei [Moscow Engineering Physics Institute (Russian Federation)

    2015-05-18

    A full-body gamma-camera based on SiPM readout is currently under development as a part of MEPHI R activity supported in the framework of Russian Megagrants program. A goal of this development is a fast upgrade of existing medical equipment with minor changes in a system design and construction in order to combine SPECT and MR instruments. A monolithic NaI(Tl) scintillator commonly used for conventional PMT-based gamma cameras has been chosen for this study. SiPMs will be coupled with the scintillator via an optical guide. To cover scintillator surface thousands of SiPMs are required, together with multichannel front-end electronics. That means that readout electronics have to be very compact, with low power consumption and low cost. 64 – channel ASIC MAROC from Weeroc provides individual readout of each SiPM and has been considered as the best choice among electronics solutions available on the market. As the photodetector parameters are the key issues here, KETEK SiPMs with high detection efficiency, low crosstalk and low noise have been chosen for this study. In order to study the proposed detection system in detail and obtain detector module parameters, required for MC simulation, a 64-channel small prototype with 6x6mm{sup 2} SiPMs has been constructed and tested. SiPMs in SMD packages have been assembled as a matrix of 8x8 elements and readout by MAROC-based board. Prototype has been tested with different shape NaI(Tl) scintillators and gammas with different energy. Dedicated algorithms for extraction of gamma-event’s energy and position are under development. They are based on fitting a matrix of individual SiPMs responses by an analytical function F(x,y). They will be tested with GEANT-simulated events and experimental data. Development of the next (engineering) prototype of SiPM’s module for gamma-camera will be started soon.

  11. SiPM-MAROC gamma-camera prototype with monolithic NaI(Tl) scintillator

    International Nuclear Information System (INIS)

    Philippov, Dmitry; Ilyin, Andrey; Belyaev, Vladimir; Popova, Elan; Buzhan, Pavel; Stifutkin, Alexei

    2015-01-01

    A full-body gamma-camera based on SiPM readout is currently under development as a part of MEPHI R activity supported in the framework of Russian Megagrants program. A goal of this development is a fast upgrade of existing medical equipment with minor changes in a system design and construction in order to combine SPECT and MR instruments. A monolithic NaI(Tl) scintillator commonly used for conventional PMT-based gamma cameras has been chosen for this study. SiPMs will be coupled with the scintillator via an optical guide. To cover scintillator surface thousands of SiPMs are required, together with multichannel front-end electronics. That means that readout electronics have to be very compact, with low power consumption and low cost. 64 – channel ASIC MAROC from Weeroc provides individual readout of each SiPM and has been considered as the best choice among electronics solutions available on the market. As the photodetector parameters are the key issues here, KETEK SiPMs with high detection efficiency, low crosstalk and low noise have been chosen for this study. In order to study the proposed detection system in detail and obtain detector module parameters, required for MC simulation, a 64-channel small prototype with 6x6mm 2 SiPMs has been constructed and tested. SiPMs in SMD packages have been assembled as a matrix of 8x8 elements and readout by MAROC-based board. Prototype has been tested with different shape NaI(Tl) scintillators and gammas with different energy. Dedicated algorithms for extraction of gamma-event’s energy and position are under development. They are based on fitting a matrix of individual SiPMs responses by an analytical function F(x,y). They will be tested with GEANT-simulated events and experimental data. Development of the next (engineering) prototype of SiPM’s module for gamma-camera will be started soon.

  12. Les TICE, un moyen d’émancipation didactique au Maroc

    Directory of Open Access Journals (Sweden)

    Asmaâ Afnakar

    2015-05-01

    Full Text Available Sur la base d’une expérience d’écriture collaborative menée sur un réseau social, nous tentons de démontrer comment un usage des TICE transgressif des textes institutionnels et de la conception de l’activité d’écrire telle qu’elle se présente dans les textes officiels au Maroc pourrait contribuer à une redéfinition des relations stéréotypées entre enseignant et apprenant et à la création d’un espace allié à celui de la classe, où l’on enrichirait les enseignements qui y sont dispensés et qui échapperait à la contrainte du temps. The ICT, a means of emancipation in Morocco. Abstract: On the basis of a collaborative writing experiment we led on a social network, we attempt to demonstrate how "informal" use of ICT in a writing classroom activity (beyond official institutional texts could help redefine the stereotypical relationship between teacher and learner and create a parallel space for classroom, where instruction is enriched and time constraint is bypassed.

  13. Socioeconomic status and tobacco expenditures among Moroccans: results of the "Maroc Tabagisme" survey.

    Science.gov (United States)

    Tachfouti, Nabil; Berraho, Mohammed; Elfakir, Samira; Serhier, Zineb; Elrhazi, Karima; Slama, Karen; Najjari, Chakib

    2010-01-01

    To investigate the relationship of sociodemographic and economic characteristics to tobacco expenses among Moroccan daily smokers. Cross-sectional ("Maroc Tabagisme" Survey) study. Random sample of 9195 subjects representative of the Moroccan population. Household subjects 15 years and older. Data were collected from selected households using a questionnaire about smoking, educational level, occupation, and household monthly income. Associations between sociodemographic and economic characteristics, smoking status, and tobacco expenses were assessed by multivariate analysis in a sample of 5959 respondents who provided details about their family income. Of 5959 participants, 28.5% of men and 2.8% of women were daily smokers. Compared with students, the odds of daily smoking were higher among blue-collar workers (odds ratio, 2.66). Tobacco expenses increased with higher family monthly income (p < .001). Moreover, smokers whose family monthly income was less than 1000 Moroccan dirham (MAD) spent 50.9% on tobacco, while those with family monthly income of 6000 MAD or higher spent 13.0 %on tobacco. There was a strong association between tobacco expenses and sociodemographic and economic characteristics. Among households with low monthly income, up to half of the monthly income is spent on tobacco.

  14. Les OPCVM actions au Maroc : mesure et analyse de performance-risque

    Directory of Open Access Journals (Sweden)

    F. El Majidi

    2017-09-01

    Full Text Available Cet article a pour objet d’élaborer des classements des OPCVM actions au Maroc sur un an et sur cinq ans selon la performance, le risque et le ratio risque rentabilité. On a utilisé les données figurant sur les tableaux des performances publiés par l’ASFIM. Les calculs des performances sur les deux horizons montrent que les classements des fonds ne se distinguent pas en termes des performances absolues et celles relatives à contrario on a constaté une instabilité dans les classements d’un horizon à un autre. Le nombre de fonds réalisant des performances sur une année est supérieur au nombre de fonds dont la performance est calculée sur cinq ans aussi bien en termes absolu qu’en termes relatif. Enfin, le classement par le ratio risque rentabilité est rigoureux, il diffère de ceux par les performances car les fonds changent de positions et se distinguent par leurs risques inhérents.

  15. Aspect Epidemiologique des Sequelles de Brulures a Marrakech, Maroc, a Travers Deux Observations

    Science.gov (United States)

    Ettalbi, S.; Ibnouzahir, M.; Droussi, H.; Wahbi, S.; Bahaichar, N.; Boukind, E.H.

    2009-01-01

    Summary La brûlure est un accident qui reste toujours très fréquent au Maroc, ce qui fait d'elle un problème de la santé publique. Les brûlures, quand elles sont graves ou profondes, entraînent de façon quasi inéluctable des séquelles fonctionnelles et esthétiques. A travers deux observations de deux enfants présentant des séquelles de brûlures graves, ayant retenti péjorativement sur leurs scolarités, on a essayé de mettre en évidence quelques facteurs incriminés dans cette tragédie (feu, petites bouteilles de gaz et le manque d'infrastructure, du personnel médical et paramédical, du matériel ainsi que de la prévention) comme étant une grande cause dans la survenue de ces séquelles. Le but de notre travail est d'énumérer ces différents facteurs intriqués, ainsi que de proposer quelques solutions, tout en insistant sur la prévention. PMID:21991156

  16. Characterization of particulate amines

    International Nuclear Information System (INIS)

    Gundel, L.A.; Chang, S.G.; Clemenson, M.S.; Markowitz, S.S.; Novakov, T.

    1979-01-01

    The reduced nitrogen compounds associated with ambient particulate matter are chemically characterized by means of ESCA and proton activation analysis. Ambient particulate samples collected on silver filters in Berkeley, California were washed with water and organic solvents, and ESCA and proton activation analysis were performed in order to determine the composition of various nitrogen compounds and the total nitrogen content. It is found that 85% of the amines originally present in ambient particulate matter can be removed by water extraction, whereas the ammonium and nitrate are completely removed. An observed increase in ammonium ion in the extract, compared with its concentration in the original sample, coupled with the commensurate decrease in amine concentration, is attributed to the hydrolysis of amide groups, which may cause analytical methods based on extraction to yield erroneous results

  17. Microwave regenerated particulate trap

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, A.C. Jr.; Yonushonis, T.M. [Cummins Engine Co., Inc., Columbus, IN (United States); Haberkamp, W.C.; Mako, F.; Len, L.K,; Silberglitt, R.; Ahmed, I. [FM Technologies, Inc., Fairfax, VA (United States)

    1997-12-31

    It has been demonstrated that a fibrous particulate filter can extract particulate matter from the diesel exhaust. However, additional engineering efforts remains to achieve the design target of 90%. It has also be shown that with minor modifications magnetrons produced for home ovens can endure a simulated diesel operating environment. Much work remains to develop a robust product ready to complete extensive engine testing and evaluation. These efforts include: (1) additional environmental testing of magnetrons; (2) vibration testing of the filter in the housing; (3) evaluating alternative methods/designs to seal the center bore; and (4) determining the optimum coating thickness that provides sufficient structural integrity while maintaining rapid heating rates.

  18. Mise en évidence d'une variation intra spécifique chez Botrytis ...

    African Journals Online (AJOL)

    SARAH

    25 avr. 2013 ... 2 Présidence de l'Université Ibn Tofaïl, Kenitra, Maroc. Auteur correspondant .... ambiante et sous lumière continue afin de favoriser davantage la .... formation de sclérotes sur les disques foliaires de tomate est observée chez ...

  19. 108 Étude bactériologique comparative des fromages frais ...

    African Journals Online (AJOL)

    AKA BOKO

    Youness CHBAB1, Abdelhak DRIOUICH1, Zakaria MENNANE2 et Mohammed OUHSSINE1. 1Laboratoire de Biotechnologie, Environnement et Qualité, Département de Biologie, Faculté des Sciences,. Université Ibn Tofaïl, BP 133, 14000 Kenitra, Maroc. 2Institut National d'Hygiène, Avenue Ibn Battouta, Rabat, Agdal, BP ...

  20. Pharmacogénétique: qu'en est-il au Maroc?

    Science.gov (United States)

    Idrissi, Meryem Janati; Ouldim, Karim; Amarti, Afaf; El Hassouni, Mohamed; Khabbal, Youssef

    2013-01-01

    La pharmacogénétique est l’étude de l'influence des variations génétiques interindividuelles sur la réponse aux médicaments, avec le but d'améliorer la prise en charge des patients en visant une médecine personnalisée. Au fait le génome de deux personnes ne diffère que par 0.1% des 3.2 milliards de paires de bases, ce qui implique les effets indésirables des médicaments, qui ont un très important impact sur le plan clinique que sur le plan économique. Or cette dernière décennie ces effets indésirables ont pu être évités grâce aux tests pharmacogénétiques. Au Maroc, la recherche en pharmacogénétique commence à susciter l'intérêt des chercheurs avec quelques études. Une toute première étude en 1986, sur l'acétylation de l'isoniazide chez la population marocaine, suivie par deux autres en 2011 se focalisant sur le métabolisme du tacrolimus et des anti-vitamines K. Ainsi l'espoir maintenant est d'identifier les majoritaires polymorphismes génétiques affectant les patients marocains, afin de leur fournir une prise en charge adaptée. PMID:23785548

  1. Le corporatisme agrarien au Maroc La trajectoire de l’Union marocaine de l’agriculture

    Directory of Open Access Journals (Sweden)

    Thierry Desrues

    2011-12-01

    Full Text Available Le secteur agricole a joué un rôle très important au Maroc durant le long règne d’Hassan II. La politique agricole a reflété les rapports de forces politiques et la capacité des élites agricoles alliées au Trône pour influencer les processus de décision. Cependant, les orientations traditionnelles de cette politique ont été remises en cause, depuis la fin des années quatre-vingt, par la libéralisation du commerce international et les contraintes financières du pays. Dans cet article, nous proposons d’apporter des éléments d’information sur l’évolution de cette politique et l’articulation des intérêts agricoles à travers le prisme de la trajectoire de l’Union Marocaine de l’Agriculture (UMA. Cette organisation professionnelle a prétendu, depuis sa constitution en 1958, au monopole de la représentation des intérêts des agriculteurs marocains, et donc du monde rural. Ce faisant, l’UMA a longtemps joué le rôle d’un véritable lobby agraire au sein des différentes institutions du royaume. Cependant, elle semble avoir perdu sa fonctionnalité à la fin des années quatre-vingt-dix, son rôle et son avenir étant depuis lors entourés d’incertitude.

  2. LUTTE CONTRE LE CANCER AU MAROC - L’APPORT DE LA FONDATION LALLA SALMA

    Directory of Open Access Journals (Sweden)

    Rachid BEKKALI

    2017-05-01

    Full Text Available Depuis la création de la Fondation Lalla Salma le 22 novembre 2005, la lutte contre le cancer au Maroc est devenue une priorité de santé publique. A cet effet, la Fondation et le Ministère de la Santé ont développé le Plan National de Prévention et de Contrôle du Cancer 2010-2019. Dans ce cadre, la Fondation mène des actions dans les domaines de la sensibilisation, de la prévention, de la détection précoce et de l’accès aux soins. De plus, la Fondation développe des activités de solidarité sociale par la construction de "Maisons de vie" pour les patients et leurs proches, la création d’un réseau de bénévoles à travers le Royaume, le développement des soins palliatifs à domicile et le soutien scolaire des orphelins du cancer.Sous le leadership de Son Altesse Royale La Princesse Lalla Salma, La Fondation mobilise les fonds nécessaires, coordonne les différentes actions et fédère les différents intervenants dans la lutte contre le cancer.En tant qu’Ambassadrice de bonne volonté de l'OMS pour la promotion de la prévention et des soins du cancer, Son Altesse Royale a aussi un rôle important dans la plaidoirie pour la lutte contre le cancer dans le monde, et soutient plusieurs pays africains pour la mise en place de programmes de prévention et de contrôle du cancer et d’accès aux médicaments.

  3. Profil des diabétiques en hémodialyse chronique: étude multicentrique au Maroc

    Science.gov (United States)

    Kabbali, Nadia; Mikou, Souad; El Pardiya, Nada Tazi; El Bardai, Ghita; Arrayhani, Mohamed; Houssaini, Tarik Sqalli

    2014-01-01

    Introduction Le diabète représente la première cause de mortalité par insuffisance rénale au Maroc. Sa prévalence selon l'Enquête Nationale sur la Population et la Santé Familiale de 2011 est de 3,3% [1]. Le but de ce travail est de déterminer la prévalence et d’étudier le profil clinique des diabétiques en hémodialyse chronique au Maroc. Méthodes Il s'agit d'une étude transversale multicentrique incluant 2066 hémodialysés chroniques dans les 39 centres d'hémodialyse de quatre régions marocaines. Résultats La prévalence du diabète en hémodialyse est 21,6%. L’âge moyen 59±13,2 ans (26-87). Le sex-ratio est de 1,9. L'IMC moyen est de 24,5 ± 4,4 kg/m2 (15-41). 42 patients sont porteurs d′une hépatite virale. La durée moyenne en HD est 39,3± 67 mois. 57% des patients gardent une diurèse résiduelle versus 43% chez les non diabétiques. Par rapport à ces derniers, nous avons noté plus d'HTA (64% versus 45%), plus de complications cardiovasculaires (23% versus 12%), un âge plus avancé à l'initiation de l'hémodialyse (55,5 versus 47 ans) et un taux de FAV proximales plus important. Conclusion La prévalence des diabétiques en hémodialyse est relativement élevée au Maroc sans tenir compte des patients qui ne bénéficient pas d’épuration extra-rénale pour des raisons socio-économiques. Le taux élevé de mortalité est imputable au retard et/ou à l'absence de la prise en charge néphrologique des diabétiques. Dans nos régions où le système sanitaire dispose de faible moyen, l'accent doit être mis sur le dépistage précoce de la néphropathie chez le diabétique. PMID:25374630

  4. Survie au cancer du sein à Rabat (Maroc) 2005-2008

    Science.gov (United States)

    Mechita, Nada Bennani; Tazi, Mohammed Adnane; Er-Raki, Abdelouahed; Mrabet, Mustapha; Saadi, Asma; Benjaafar, Noureddine; Razine, Rachid

    2016-01-01

    Introduction Le cancer du sein représente un problème de santé publique au Maroc. L’objectif de ce travail était d’estimer le taux de survie au cancer du sein chez les patientes habitant la ville de Rabat. Méthodes Etude pronostique réalisée chez les patientes diagnostiquées pour cancer du sein de 2005 à 2008, habitant la ville de Rabat et enregistrées au registre des cancers de Rabat. La date d’inclusion dans l’étude correspondait à la date de confirmation histologique du cancer. L’estimation de la survie a été réalisée par la méthode de Kaplan Meier, et la comparaison entre les différentes classes d’une variable a été réalisée par le test de log rank. L’étude des facteurs associés à la survie a été effectuée par le modèle de Cox. Résultats Durant la période d’étude 628 cas de cancer du sein ont été collectés. Le pourcentage de décès était de 19,9%. La survie globale à un an était de 97,1%, elle était de 89,2% à 3 ans et de 80,6 % à 5 ans. En analyse multivariée la survie au cancer du sein était statistiquement moins bonne chez les patientes âgées de plus de 70 ans (p<0,001), ayantune grande taille de tumeur (p<0,001), un stade avancé d’adénopathies (p=0,007), présentant des métastases (p<0,001) et non traitées par hormonothérapie (p=0,002). Conclusion Une grande taille de la tumeur et la présence de métastases sont des facteurs de mauvais pronostic du cancer du sein d’où la nécessité de renforcer les programmes de dépistage. PMID:28292106

  5. Airborne Particulate Threat Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Patrick Treado; Oksana Klueva; Jeffrey Beckstead

    2008-12-31

    Aerosol threat detection requires the ability to discern between threat agents and ambient background particulate matter (PM) encountered in the environment. To date, Raman imaging technology has been demonstrated as an effective strategy for the assessment of threat agents in the presence of specific, complex backgrounds. Expanding our understanding of the composition of ambient particulate matter background will improve the overall performance of Raman Chemical Imaging (RCI) detection strategies for the autonomous detection of airborne chemical and biological hazards. Improving RCI detection performance is strategic due to its potential to become a widely exploited detection approach by several U.S. government agencies. To improve the understanding of the ambient PM background with subsequent improvement in Raman threat detection capability, ChemImage undertook the Airborne Particulate Threat Assessment (APTA) Project in 2005-2008 through a collaborative effort with the National Energy Technology Laboratory (NETL), under cooperative agreement number DE-FC26-05NT42594. During Phase 1 of the program, a novel PM classification based on molecular composition was developed based on a comprehensive review of the scientific literature. In addition, testing protocols were developed for ambient PM characterization. A signature database was developed based on a variety of microanalytical techniques, including scanning electron microscopy, FT-IR microspectroscopy, optical microscopy, fluorescence and Raman chemical imaging techniques. An automated particle integrated collector and detector (APICD) prototype was developed for automated collection, deposition and detection of biothreat agents in background PM. During Phase 2 of the program, ChemImage continued to refine the understanding of ambient background composition. Additionally, ChemImage enhanced the APICD to provide improved autonomy, sensitivity and specificity. Deliverables included a Final Report detailing our

  6. Nicolas Michel, Une économie de subsistances. Le Maroc précolonial, IFAO, Le Caire, 1997.

    Directory of Open Access Journals (Sweden)

    Sylvie Denoix

    2004-11-01

    Full Text Available Le titre de cet ouvrage peut apparaître paradoxal si l'on considère, comme le rappelle Nicolas Michel, que le Maroc, dès avant le XIXe siècle, était inséré dans une économie marchande internationale "faisant circuler dans tout le pays produits et espèces monétaires". En fait, les produits de première nécessité échappent au grand négoce et font plutôt l'objet d'un troc, d'un échange contre services, hors système monétaire. Néanmoins, dans un souci de rigueur méthodologique, l'auteur nous garde...

  7. Traditions matrimoniales dans la région de Rabat-Salé-Zemmour-Zaer au Maroc

    OpenAIRE

    Hami, H.; Soulaymani, A.; Mokhtari, A.

    2011-01-01

    La pratique des mariages consanguins est très répandue au Moyen-Orient, en Afrique du Nord et dans le Sud-Ouest Asiatique où 20 à plus de 50 % de mariages sont consanguins. L’analyse d’un échantillon de 270 femmes mariées, pris au hasard dans le service de Maternité de l’Hôpital Souissi à Rabat (2004-2005), a fait l’objet d’une étude prospective visant à déterminer la fréquence des mariages consanguins dans la région de Rabat-Salé-Zemmour-Zaer au Maroc. Les résultats obtenus montrent que 20...

  8. Le premier partenariat public-privé pour l’irrigation au Maroc : durable pour tous ?

    Directory of Open Access Journals (Sweden)

    Houdret Annabelle

    2016-03-01

    Full Text Available Les partenariats public-privé (PPP sont un phénomène relativement récent dans le secteur de l’irrigation ; le projet El Guerdane au Maroc est ainsi le premier de son genre. Inauguré en 2008, le projet alimente en eau 10 000 ha de plantations d’agrumes. Les banques internationales de développement le présentent comme un succès, mais l’impact sur le développement local est, au mieux, mitigé. Alors que certains agriculteurs ont bénéficié de cette initiative, d’autres ont été marginalisés, en termes d’accès à l’eau, aux terres fertiles et au développement. Fondé sur des recherches de terrain extensives conduites entre 2005 et 2013, l’article révèle trois problèmes cruciaux du projet PPP : des effets souvent négatifs sur les revenus des acteurs et sur le développement ; un partage inégal des coûts, des bénéfices et des risques entre les secteurs public et privé ; un impact environnemental incertain. Sur la base de ces résultats, l’étude situe le projet dans le contexte plus large de l’évolution des rapports de force politico-économiques au Maroc.

  9. Les déterminants du statut “perdu de vue” chez les patients pris en charge pour cancer au Maroc: situation avant le Plan Cancer

    Science.gov (United States)

    Najdi, Adil; Berraho, Mohamed; Bendahhou, Karima; Obtel, Majdouline; Zidouh, Ahmed; Errihani, Hassan; Nejjari, Chakib

    2014-01-01

    Introduction Le cancer au Maroc représente un problème majeur de santé publique, sa prise en charge doit être globale, active et complète pour tous les patients. L'objectif de ce travail était d'estimer la fréquence des perdus de vue « PDV » en oncologie au Maroc durant la première année de suivi et de déterminer les facteurs associés à ce problème. Méthodes Par une étude rétrospective portant sur 2854 dossiers de malades hospitalisés dans les trois principaux centres d'oncologie au Maroc depuis janvier 2003 jusqu’à juin 2007 et concernant les cinq principales localisations de cancer au Maroc, nous avons cherché la date des dernières nouvelles des patients ayant un recul de 18 mois minimum afin de déterminer le statut de ces malades après un an de suivi. Résultats La moyenne d’âge était de 52±14 ans, une proportion féminine de 63%, les sujets actifs constituaient 28%, les mariés 71%, les analphabètes 51%, 70% des patients habitaient en milieu urbain et seulement 11% des malades disposaient d'une couverture sociale. La localisation cancéreuse la plus fréquente était le poumon (23,8%) suivie du colon-rectum (23,5%) puis le col (21,9%), le sein (20,4%) et les lymphomes (10,4%). Le taux des «PDV» à un an de suivi était de 48%, ce statut était significativement lié au sexe, à l’âge, au NSE et au statut matrimonial. Sur le plan médical, le statut «PDV» était lié à la localisation du cancer, au stade de diagnostic et au type de traitement reçu. Conclusion Notre étude a mis en évidence la grande ampleur du problème des PDV en cancérologie au Maroc ainsi que ces déterminants. Ces résultats incitent tous les acteurs dans le domaine de la cancérologie à collaborer ensemble pour prendre les mesures qui s'imposent pour y pallier PMID:25400850

  10. Les politiques d’appui à l’agriculture familiale au Brésil : quelques éléments de comparaison avec le Maroc

    Directory of Open Access Journals (Sweden)

    Philippe Bonnal

    2015-10-01

    Full Text Available Au Brésil comme au Maroc, le secteur agricole est marqué par des différences extrêmes en termes de taille d’exploitation, ainsi que de niveaux d’équipement, de capitalisation et de techniques. L’article présente la politique brésilienne d’appui à l’agriculture familiale, et quelques éléments de comparaison avec les choix faits au Maroc. Les politiques agricoles brésiliennes proposent depuis une vingtaine d’années un appui spécifique aux exploitations familiales, avec notamment la constitution d’un ministère spécifique. De nombreux dispositifs d’appui à l’agriculture familiale ont été mis en place, dont notamment des crédits à taux préférentiel et des programmes d’achat de denrées agricoles pour les institutions publiques (écoles, hôpitaux, etc.. Dans les zones rurales particulièrement fragiles, des dispositifs permettent une coordination entre l’ensemble des politiques publiques concernant ces zones. Enfin, la conception et la mise en oeuvre de ces politiques publiques se font avec une forte implication des syndicats agricoles. Les politiques publiques brésiliennes et marocaines reconnaissent la dualité du monde agricole, mais cette dualité est définie par zone au Maroc, tandis qu’elle est fondée sur des caractéristiques explicites des exploitations au Brésil. Dans les deux pays, le coeur des politiques publiques d’appui aux exploitations familiales porte sur l’aide à l’investissement. Au-delà de ce coeur commun, les politiques brésiliennes ont plus spécifiquement développé des approches au niveau des territoires locaux et associent plus fortement qu’au Maroc les organisations professionnelles agricoles représentant l’agriculture familiale dans la conception de l’action publique. La comparaison des politiques agricoles au Maroc et au Brésil sur quelques éléments permet de souligner la forte étendue des choix qu’il est possible de considérer, pour définir des

  11. ADVANCED HYBRID PARTICULATE COLLECTOR

    Energy Technology Data Exchange (ETDEWEB)

    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

    2001-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be

  12. Electrically heated particulate filter restart strategy

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2011-07-12

    A control system that controls regeneration of a particulate filter is provided. The system generally includes a propagation module that estimates a propagation status of combustion of particulate matter in the particulate filter. A regeneration module controls current to the particulate filter to re-initiate regeneration based on the propagation status.

  13. Electrical diesel particulate filter (DPF) regeneration

    Science.gov (United States)

    Gonze, Eugene V; Ament, Frank

    2013-12-31

    An exhaust system that processes exhaust generated by an engine includes a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates from the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates within the exhaust as it passes therethrough. Heat generated by combustion of the particulates induces combustion of particulates within the DPF.

  14. Etude séro-épidémiologique de la leishmaniose canine au centre du Maroc

    Science.gov (United States)

    Fellah, Hajiba; Doughmi, Oursula; Maniar, Saâd; Lalami, Abdelhakim El Ouali

    2014-01-01

    Dans le monde, la leishmaniose viscérale humaine est connue pour avoir comme principale source d'infection les Canidés domestiques et sauvages. Au centre du Maroc, les données épidémiologiques, cliniques et parasitologiques sur la leishmaniose canine, sont quasiment inexistantes. Ce travail traite une étude prospective au cours de laquelle 61 sérums canins ont été analysés par un test rapide et par l'immunofluorescence indirecte. La sensibilité du test rapide par rapport à celle de l'immunofluorescence indirecte (IFI) est de 33,33%. La fréquence de la maladie chez les chiens s’élève à 9,83% (Test Rapide) et 24,59% (IFI). 73,33% des cas canins positifs à la sérologie sont asymptomatiques. Ce sont les jeunes chiens de moins de 5 ans qui sont les plus fréquemment atteints avec une sensibilité de la race Berger Allmand à l'infection. Cette étude a permis de mettre en évidence la présence de chiens leishmaniens (15 chiens séropositifs parmi 61) et de prouver l'existence du réservoir canin. Une stratégie de prévention active doit être mise en place. PMID:25852791

  15. Monsieur Omar Fassi Fihri Secrétaire perpétuel Académie HASSAN II des Sciences et Techniques Royaume du Maroc

    CERN Document Server

    Maximilien Brice

    2010-01-01

    CERN-HI-1007135 01: M. Gouighri, Boursier de l’Académie des Sciences, Université Hassan II; J. Collot, Directeur du Laboratoire international associé; R. Heuer,\tDirecteur général du CERN;O. Fassi Fehri, Secrétaire perpétuel, Académie Hassan II des Sciences et Techniques, Maroc; S. Boutouil, Boursière du Laboratoire international associé; R. Klapisch, Fondation Partager le Savoir, Président et fondateur; G.Carnot, Président de la Fondation Carnot.

  16. Connaissances des médecins généralistes de Mohammedia (Maroc) concernant le dépistage du cancer du sein

    Science.gov (United States)

    Zine, Karima; Nani, Samira; Lahmadi, Imad Ait; Maaroufi, Abderrahmane

    2016-01-01

    Introduction Le cancer du sein représente un problème de santé publique majeur au Maroc. C'est le premier cancer chez la femme. L'objectif de ce travail était d'évaluer les connaissances des médecins généralistes (MG) en matière de dépistage du cancer du sein dans la préfecture de Mohammedia Maroc. Méthodes Nous avons mené une étude transversale, descriptive, exhaustive incluant les 97 MG exerçant dans les établissements de soins de santé de base du secteur public et privé de la province de Mohammedia. Résultats Le taux de participation était de 87%. L'âge moyen des MG était de 49,6 ± 8,1. Quatre-vingt pour cent (n=55) des MG ont donné une incidence incorrecte, 77,6% (n=85) ont reconnu l'existence d'un plan national de prévention et de contrôle du cancer (PNPCC) au Maroc, et 67,1 des MG ont rapporté l'existence d'un registre du cancer au Maroc. Le secteur d'activité était associé significativement avec les connaissances des MG sur le PNPCC et sur l'existence d'un guide de détection précoce du cancer du sein avec respectivement (p=0,003 et p=0,001). Une association significative entre l'ancienneté et l'existence d'un guide de détection précoce du cancer du sein et d'un registre du cancer du sein a été retrouvée avec (respectivement p=0,005 et p=0.002). Conclusion À la lumière de ces résultats il faudra renforcer les connaissances et les pratiques des MG par la promotion de la formation initiale et continue sur le dépistage. PMID:27800098

  17. Les effets bénéfiques de l'accompagnement du patient cancéreux: particularités du Maroc

    Science.gov (United States)

    Lkhoyaali, Sihame; Aitelhaj, Meryem; Errihani, Hassan

    2014-01-01

    Au Maroc la majorité des patients âgés cancéreux sont pris en charge par leurs proches l'accompagnement des patients est à l'origine de conséquences émotionnelles psychiques et financières négatives mais en contrepartie il est à l'origine de plusieurs effets bénéfiques à savoir un resserrement des liens familiaux, une surestime du soi et il est la source d'un bien-être affectif et spirituel qui permet de faire face à la maladie. PMID:25722766

  18. Particulate carbon in the atmosphere

    International Nuclear Information System (INIS)

    Surakka, J.

    1992-01-01

    Carbonaceous aerosols are emitted to the atmosphere in combustion processes. Carbon particles are very small and have a long residence time in the air. Black Carbon, a type of carbon aerosol, is a good label when transport of combustion emissions in the atmosphere is studied. It is also useful tool in air quality studies. Carbon particles absorb light 6.5 to 8 times stronger than any other particulate matter in the air. Their effect on decreasing visibility is about 50 %. Weather disturbances are also caused by carbon emissions e.g. in Kuwait. Carbon particles have big absorption surface and capacity to catalyze different heterogenous reactions in air. Due to their special chemical and physical properties particulate carbon is a significant air pollution specie, especially in urban air. Average particulate carbon concentration of 5.7 μg/m 2 have been measured in winter months in Helsinki

  19. Understanding particulate coating microstructure development

    Science.gov (United States)

    Roberts, Christine Cardinal

    How a dispersion of particulates suspended in a solvent dries into a solid coating often is more important to the final coating quality than even its composition. Essential properties like porosity, strength, gloss, particulate order, and concentration gradients are all determined by the way the particles come together as the coating dries. Cryogenic scanning electron microscopy (cryoSEM) is one of the most effective methods to directly visualize a drying coating during film formation. Using this method, the coating is frozen, arresting particulate motion and solidifying the sample so that it be imaged in an SEM. In this thesis, the microstructure development of particulate coatings was explored with several case studies. First, the effect of drying conditions was determined on the collapse of hollow latex particles, which are inexpensive whiteners for paint. Using cryoSEM, it was found that collapse occurs during the last stages of drying and is most likely to occur at high drying temperatures, humidity, and with low binder concentration. From these results, a theoretical model was proposed for the collapse of a hollow latex particle. CryoSEM was also used to verify a theoretical model for the particulate concentration gradients that may develop in a coating during drying for various evaporation, sedimentation and particulate diffusion rates. This work created a simple drying map that will allow others to predict the character of a drying coating based on easily calculable parameters. Finally, the effect of temperature on the coalescence and cracking of latex coatings was explored. A new drying regime for latex coatings was identified, where partial coalescence of particles does not prevent cracking. Silica was shown to be an environmentally friendly additive for preventing crack formation in this regime.

  20. CDC WONDER: Daily Fine Particulate Matter

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Daily Fine Particulate Matter data available on CDC WONDER are geographically aggregated daily measures of fine particulate matter in the outdoor air, spanning...

  1. Particulate Matter: a closer look

    NARCIS (Netherlands)

    Buijsman E; Beck JP; Bree L van; Cassee FR; Koelemeijer RBA; Matthijsen J; Thomas R; Wieringa K; LED; MGO

    2005-01-01

    The summary in booklet form 'Fijn stof nader bekeken' (Particulate Matter: a closer look) , published in Dutch by the Netherlands Environmental Assessment Agency (MNP) and the Environment and Safety Division of the National Institute for Public Health and the Environment (RIVM), has been designed to

  2. Transport phenomena in particulate systems

    CERN Document Server

    Freire, José Teixeira; Ferreira, Maria do Carmo

    2012-01-01

    This volume spans 10 chapters covering different aspects of transport phenomena including fixed and fluidized systems, spouted beds, electrochemical and wastewater treatment reactors. This e-book will be valuable for students, engineers and researchers aiming to keep updated on the latest developments on particulate systems.

  3. Global Particulate Matter Source Apportionment

    Science.gov (United States)

    Lamancusa, C.; Wagstrom, K.

    2017-12-01

    As our global society develops and grows it is necessary to better understand the impacts and nuances of atmospheric chemistry, in particular those associated with atmospheric particulate matter. We have developed a source apportionment scheme for the GEOS-Chem global atmospheric chemical transport model. While these approaches have existed for several years in regional chemical transport models, the Global Particulate Matter Source Apportionment Technology (GPSAT) represents the first incorporation into a global chemical transport model. GPSAT runs in parallel to a standard GEOS-Chem run. GPSAT uses the fact that all molecules of a given species have the same probability of undergoing any given process as a core principle. This allows GPSAT to track many different species using only the flux information provided by GEOS-Chem's many processes. GPSAT accounts for the change in source specific concentrations as a result of aqueous and gas-phase chemistry, horizontal and vertical transport, condensation and evaporation on particulate matter, emissions, and wet and dry deposition. By using fluxes, GPSAT minimizes computational cost by circumventing the computationally costly chemistry and transport solvers. GPSAT will allow researchers to address many pertinent research questions about global particulate matter including the global impact of emissions from different source regions and the climate impacts from different source types and regions. For this first application of GPSAT, we investigate the contribution of the twenty largest urban areas worldwide to global particulate matter concentrations. The species investigated include: ammonium, nitrates, sulfates, and the secondary organic aerosols formed by the oxidation of benzene, isoprene, and terpenes. While GPSAT is not yet publically available, we will incorporate it into a future standard release of GEOS-Chem so that all GEOS-Chem users will have access to this new tool.

  4. Evaluation d’une grille de supervision des laboratoires des leishmanioses cutanées au Maroc

    Science.gov (United States)

    El Mansouri, Bouchra; Amarir, Fatima; Hajli, Yamina; Fellah, Hajiba; Sebti, Faiza; Delouane, Bouchra; Sadak, Abderrahim; Adlaoui, El Bachir; Rhajaoui, Mohammed

    2017-01-01

    Introduction Afin d’évaluer une grille de contrôle standardisée de laboratoire de diagnostic des leishmanioses, comme nouveau outil de supervision. Méthodes Un essai pilote a été pratiqué sur sept laboratoires provinciaux, appartenant à quatre provinces au Maroc, en suivant l’évolution de leurs performances tous les deux ans, entre l’année 2006 et 2014. Cette étude détaille la situation des laboratoires provinciaux avant et après la mise en œuvre de la grille de supervision. Au total vingt et une grille sont analysées. Résultats En 2006, les résultats ont montré clairement une insuffisance des performances des laboratoires: besoin en formation (41.6%), personnel pratiquant le prélèvement cutané (25%), pénurie en matériels et réactifs (65%), gestions documentaire et local non conformes (85%). Différentes actions correctives ont été menées par le Laboratoire National de Référence des Leishmanioses (LNRL) durant la période d’étude. En 2014, le LNRL a enregistré une nette amélioration des performances des laboratoires. Les besoins en matière de formation, qualité du prélèvement, dotation en matériels et réactifs ont été comblés et une coordination efficace s’est établie entre le LNRL et les laboratoires provinciaux. Conclusion Ceci montre l'efficacité de la grille comme outil de supervision de grande qualité, et comme pierre angulaire de tout progrès qui doit être obtenu dans les programmes de lutte contre les leishmanioses. PMID:29187922

  5. Protective coatings for commercial particulates

    DEFF Research Database (Denmark)

    Kindl, B.; Teng, Y.H.; Liu, Y.L.

    1994-01-01

    SiC/Al composites are in large-scale production with Al-Si alloy matrices. The same composites with pure Al or low Si matrices need diffusion barriers on the SiC reinforcement to control the interfacial reaction. The present paper describes various approaches taken to obtain protective coatings...... of alumina and zirconia on SiC particulates by sol-gel techniques. Aqueous and organic precursors have been used. The extent of the reaction, i.e., the Si and Al4C3 content in the matrix, was determined by differential thermal analysis and X-ray diffraction. The reaction rates of some coated particulates...... in liquid Al are decreased by as much as one order of magnitude during the first 15 min of immersion. Pretreatments of the SiC surface, the composition and thickness of the coating interphase and heat treatments of the coated materials have been studied, and are discussed in relation to their effect...

  6. Polymorphisme de l'apolipoprotéine E dans la population du nord du Maroc: fréquence et influence sur les paramètres lipidiques

    Science.gov (United States)

    Benyahya, Fatiha; Barakat, Amina; Ghailani, Naima; Bennani, Mohcine

    2013-01-01

    Introduction L'objectif de ce travail est de déterminer les fréquences alléliques et génotypiques des sites polymorphes situés dans le gène de l'apolipoprotéine E (apo E) ainsi que leur impact sur les paramètres cliniques et lipidiques dans un échantillon de la population du nord du Maroc cliniquement diagnostiqué ADH. Méthodes Le génotype de l'apo E a été analysé par séquençage direct chez 46 patients cliniquement diagnostiqués ADH selon les critères standards. Résultats Les fréquences des allèles epsilon 3, epsilon 2 et epsilon 4 ont été respectivement 78.3%, 2.2% et 19.6%. La fréquence de l'allèle epsilon 4 est très élevée chez la population du nord du Maroc en comparaison avec les populations des autres régions marocaines. Elle est similaire à celle rapportée dans les pays de l'Europe du nord. Les taux du cholestérol total, du cholestérol LDL ainsi que la présence des xanthomes et les maladies cardiovasculaires ne différent pas entre les génotypes de l'apoE. En revanche, les résultats ont montré une influence de l'allèle epsilon4 sur le taux des triglycérides chez les sujets obèses. Conclusion Le génotype de l'apoE ne peut expliquer le phénotype clinique et biochimique présenté par des patients du Nord du Maroc cliniquement diagnostiqués ADH. PMID:24396563

  7. Changements climatiques au Maroc: quels systèmes de culture et quelles biotechnologies pour s’y adapter ?

    Directory of Open Access Journals (Sweden)

    Abdelhadi AIT HOUSSA

    2017-09-01

    scale use of seawater in agriculture or finding new salinity tolerant cultivars. In Morocco, we should think of desalinization with renewable energies (solar, wind and the use of this water mainly in coastal areas where climate, land quality, sun and wind are adequate to these projects. To anticipate the future of food security of the country, attention should be given to the use of readily available resources to overcome the structural deficit in wheat starch and animal protein. The study suggests the use of other starch sources that Morocco can produce easily such as potato. For animal protein, we suggest fisheries resources which are still underused by the population. Résumé On présente une étude prospective concernant l’impact probable des changements climatiques sur les systèmes de culture et d’élevage au Maroc. D’après le constat de terrain et dans les limites de ce que signifie ce genre d’étude, l’effet direct du réchauffement climatique peut conduire à terme (et c’est déjà le cas dans certaines contrées à la nécessité d’une redistribution variétale pour des espèces exigeantes en froid comme les rosacées. Des variétés de pomme, telle que le groupe des Golden, risquent de disparaître des montagnes pour laisser la place à d’autres moins exigeantes comme le groupe des Gala. Le bananier et l’avocatier risquent de migrer vers les régions un peu plus continentales, l’olivier et les agrumes un peu plus vers le pied de la montagne. Le réchauffement climatique peut aussi obliger à faire évoluer les systèmes d’élevage et de culture en faisant déplacer la frontière de la sécheresse un peu plus vers le centre et le nord du pays; l’aride serait peut-être envahi par la désertification, le semi-aride passerait en partie à l’étage aride et le Bour dit favorable en partie dans le semi-aride. Comme corollaire à ce changement, il faudrait s’attendre à une perte de potentiel de ressources en eau qui obligerait

  8. Aspects épidemiocliniques et évolutifs chez 157 cas de leishmaniose cutanée au Maroc

    Science.gov (United States)

    Hjira, Naoufal; Frikh, Rachid; Marcil, Tarik; Lamsyah, Hanane; Oumakhir, Siham; Baba, Noureddine; Boui, Mohammed

    2014-01-01

    Connue au Maroc depuis la fin du XIX siècle, la leishmaniose cutanée (LC) constitue un problème de santé publique dans notre pays. Le but de notre travail est de décrire le profil épidémioclinique et l’évolution post thérapeutique chez les patients ayant une leishmaniose cutanée dans notre contexte. Nous avons effectué une étude rétrospective, basée sur l'exploitation des dossiers de malades ayant présenté une leishmaniose cutanée confirmée entre janvier 2003 et décembre 2012. Nous avons colligés 157 cas de leishmaniose cutanée. L’âge moyen des patients était de 34.5 ans avec des extrêmes de 6 ans à 63 ans. Le sex-ratio était de 2.34 H/F. La durée d’évolution moyenne des lésions était de 3,6 mois avec des extrêmes de 2 semaines à 10 mois. Les lésions étaient uniques dans 29.5% des cas. Les lésions siégeaient sur membres dans 63%. La forme ulcèro- croûteuse touchait plus de 48%. Le Glucantime était utilisé dans 29.3% des cas, l'azote liquide était utilisé chez 111 autres. L’évolution post-thérapeutique était favorable avec disparition quasi-complète des lésions dans un délai variant de 6 à 10 semaines, au prix de cicatrices inesthétiques chez 14 patients. La leishmaniose cutanée continue à poser un vrai problème de santé publique dans notre pays. L’émergence de formes sévères et résistantes à travers le monde doit inciter à multiplier et renforcer les mesures prophylactiques. PMID:25309671

  9. Alteration hydrothermale et deformation ductile des roches volcaniques acides associees au gisement sulfure de draa sfar (Jebilet Centrales, Maroc

    Directory of Open Access Journals (Sweden)

    Zinbi, Y.

    2005-12-01

    Full Text Available The volcanics and volcanoclastic rocks of Draa Sfar (Central Jebilet, Moroccan hercynian belt are affected by ductile stress and hydrothermal alteration accompanied by a weak degree of metamorphism (greenschist facies. Some N-S oriented shearing zones, affect locally these formations while being the site of an important hydrothermal activity. The consequences of these transformations from a non to slightly- deformed rhyodacite, show that through these ductile shearing zones: (1 the mineralogical assemblage of hydrothermal alteration is essentially formed by chlorite, sericite, quartz and magnetite; (2 the gradual increase of the alteration indexes is accompanied by the destruction of the phenocrists and the recrystallization of the matrix by phyllosilicates and quartz; (3 the progressive transfer of material is more intense in the more deformed zones where the values of Ti, Al and Zr remain constant. These shearing zones played a very important role in the circulation of fluids and the transformation of the rhyodacite of Draa Sfar.Les roches volcaniques et volcanoclastiques de Draa Sfar (Jebilet centrales, Maroc hercynien sont affectées par une déformation ductile accompagnée d’un métamorphisme de faible degré (faciès schistes verts et d’une altération hydrothermale. Des zones de cisaillement de direction N-S, ont affecté localement ces formations tout en étant vecteurs d’une importante activité hydrothermale. Le suivi de ces transformations à partir de la rhyodacite non ou peu déformée, montre qu’à travers ces zones de cisaillements ductiles : (1 l’assemblage minéralogique d’altération hydrothermale est formé essentiellement de chlorite, de séricite, de quartz et de magnétite ; (2 l’augmentation graduelle des indices d’altération s’exprime par la destruction des phénocristaux au profit d’une matrice recristallisée en phyllosilicates et quartz ; (3 le transfert progressif de la matière est plus intense

  10. PIXE analysis of vehicle exhaust particulate

    International Nuclear Information System (INIS)

    Shi Xianfeng; Yao Huiying; Liu Bo; Sun Minde; Xu Huawei; Mi Yong; Shen Hao

    2001-01-01

    PIXE technique on the analysis of vehicle exhaust particulate is introduced. The clement composition and concentration of particulate are obtained. Some elements which are related to environmental pollution such as sulfur lead, silicon and manganese, were analyzed and discussed in detail by PIXE technique Nowadays although unleaded gasoline is widely used, the lead concentration is still very high in exhaust particulate. The concentrations of silicon and manganese in exhaust particulate from different model vehicles are also quite high from measurements. It shows that an evidence for exhaust pollution control could be provided from this work

  11. Caractérisation isotopique des eaux du granite et de l’auréole métamorphique d’Oulmès (Maroc central)

    OpenAIRE

    Olive, Philippe; Dassargues, Alain; Griere, Olivier; Ruthy, Ingrid; El Youbi, A.

    2006-01-01

    Dans le bassin d’Oulmès sont exploitées et commercialisées par la société des Eaux Minérales d’Oulmès qui constitue le plus gros embouteilleur d’eaux minérales du Maroc :Sidi Ali Lala Haya. Le pluton granitique, d’âge hercynien, d’Oulmès est un granite à biotite et muscovite. Il présente une fracturation très marquée et un système filonien très développé. L’altération, très poussée, se manifeste par une arénitisation généralisée qui s’étend en profondeur. Le kaolin caractérise cette altér...

  12. La cassitérite zonée du gisement de Sokhret Allal (granite des Zaër ; Maroc central) : composition chimique et phases fluides associées

    OpenAIRE

    Giuliani, Gaston

    1987-01-01

    La composition chimique d'une cassitérite zonée provenant du gisement de tungstène-étain de Sokhret Allal (Maroc central) a été analysée par microsonde électronique. La zonation optique du minéral correspond à des variations en éléments mineurs tels Fe et Ti. Les inclusions fluides contemporaines du dépôt de la cassitérite sont primaires et constituées de fluides typiquement aqueux appartenant au système H2O-NaCl. La contribution de ces nouvelles données dans la métallogenèse W-Sn du Maroc ce...

  13. De quels ingénieurs parle-t-on ? Situation et trajectoires des ingénieurs des grandes écoles. Le cas du Maroc

    Directory of Open Access Journals (Sweden)

    Pierre Vermeren

    2009-05-01

    Full Text Available Cet article est consacré au cas des « ingénieurs de conception » marocains, formés la plupart du temps dans les grandes écoles françaises. Cette fraction des ingénieurs marocains (dont la majorité est formée dans les écoles d'ingénieurs du Maroc n'est pas loin de constituer une véritable aristocratie de fonction. Ce phénomène illustre la structure sociale très inégalitaire du Maroc et la stratification opérée par la monarchie (le Makhzen pour sélectionner ses élites, qui sont aujourd'hui des élites à la fois technocratiques et sociales. Cette domination des « technocrates » sur l'appareil d'Etat marocain, analysée ici à travers des publics étudiants de grandes écoles, s'accompagne de l'émergence d'une contre-élite sociale de contestation. Les écoles d'ingénieurs de second rang, peuplées par les éléments des classes moyennes, ont été le premier terreau des mouvements islamistes en milieu universitaire. Elles produisent aujourd'hui une contre-élite politique et sociale qui piétine aux portes du vrai pouvoir.

  14. Profil épidémiologique de l'insuffisance rénale terminale à l'hôpital Militaire de Rabat, Maroc

    Science.gov (United States)

    Asserraji, Mohammed; Maoujoud, Omar; Belarbi, Marouane; Oualim, Zouhir

    2015-01-01

    L'Insuffisance rénale chronique terminale (IRCT) est un enjeu majeur de sante publique au Maroc à cause de ses conséquences médicales et socioéconomiques. L'objectif de ce travail est d’évaluer le profil épidémiologique de l'IRCT à l'hôpital militaire de rabat, Maroc. Il s'agit d'une enquête rétrospective pendant quatre ans (1er janvier 2007 au 31 décembre 2010). Tous les cas d'IRCT (diminution permanente du débit de filtration glomérulaire (DFG) < 15 ml/min/1.73m2, pendant ≥ 3 mois) ont été inclus. 203 patients ont commencé la dialyse durant cette période, 130 hommes (64%) et 73 femmes (36%), l’âge moyen était de 49,92 ans (06 - 80 ans). la néphropathie d'origine indéterminée représente la première cause d'IRCT dans notre série (27,1%) suivie de la néphropathie diabétique (24,6%), des glomérulonéphrites chroniques (22,7) et de la néphropathie d'origine vasculaire (10,8%). 131 patients (64,5%) n'ont pas eu de suivi néphrologique pré dialytique. une prise en charge globale de cette pathologie est nécessaire. PMID:26309471

  15. Airborne particulate matter in spacecraft

    Science.gov (United States)

    1988-01-01

    Acceptability limits and sampling and monitoring strategies for airborne particles in spacecraft were considered. Based on instances of eye and respiratory tract irritation reported by Shuttle flight crews, the following acceptability limits for airborne particles were recommended: for flights of 1 week or less duration (1 mg/cu m for particles less than 10 microns in aerodynamic diameter (AD) plus 1 mg/cu m for particles 10 to 100 microns in AD); and for flights greater than 1 week and up to 6 months in duration (0.2 mg/cu m for particles less than 10 microns in AD plus 0.2 mg/cu m for particles 10 to 100 microns in AD. These numerical limits were recommended to aid in spacecraft atmosphere design which should aim at particulate levels that are a low as reasonably achievable. Sampling of spacecraft atmospheres for particles should include size-fractionated samples of 0 to 10, 10 to 100, and greater than 100 micron particles for mass concentration measurement and elementary chemical analysis by nondestructive analysis techniques. Morphological and chemical analyses of single particles should also be made to aid in identifying airborne particulate sources. Air cleaning systems based on inertial collection principles and fine particle collection devices based on electrostatic precipitation and filtration should be considered for incorporation into spacecraft air circulation systems. It was also recommended that research be carried out in space in the areas of health effects and particle characterization.

  16. Dans le tourbillon des particules

    CERN Document Server

    Zito, Marco

    2015-01-01

    Accélérateurs géants, détecteurs complexes, particules énigmatiques... La physique subatomique peut sembler bien intimidante pour le novice. Et pourtant, qui n a jamais entendu parler du boson de Higgs et du CERN, le laboratoire européen où il a été découvert en 2012 ? Nul besoin d être un spécialiste pour comprendre de quoi il s agit. Aujourd hui, une théorie extraordinairement élégante, le Modèle Standard, décrit tous les résultats des expériences dans le domaine. Trente-sept particules élémentaires et quatre forces fondamentales : c est tout ce dont nous avons besoin pour expliquer la matière et l Univers ! Ce livre, destiné à un large public, raconte sans équations le long parcours qui a abouti au Modèle Standard. Ce parcours, parfois sinueux, a été entamé lorsque les Grecs anciens, et peut-être d autres avant eux, ont imaginé que la matière est composée de petites « billes ». Il faudra attendre plusieurs siècles pour qu on réalise que la matière, à l échelle micros...

  17. Kuwaiti oil fires—Particulate monitoring

    Science.gov (United States)

    Husain, Tahir; Amin, Mohamed B.

    The total suspended particulate (TSP) matters using a high-volume sampler and inhalable particulate matters using PM-10 samplers were collected at various locations in the Eastern Province of Saudi Arabia during and after the Kuwaiti oil fires. The collected samples were analysed for toxic metals and oil hydrocarbon concentrations including some carcinogenic organic compounds in addition to gravimetric analysis. The concentration values of particulate matters were determined on a daily basis at Dhahran. Abqaiq, Rahima, Tanajib and Jubail locations. The analyses of the filters show a high concentration of the inhalable particulate at various locations, especially when north or northwest winds were blowing. It was found that the inhalable particulate concentration exceeded the Meteorology and Environmental Protection Administration (MEPA) permissible limit of 340 μg m- 3 at most of these locations during May-October 1991. A trend between the total suspended particulate and inhalable particulate measured concurrently at the same locations was observed and a regression equation was developed to correlate PM-10 data with the total suspended particulate data.

  18. Air Quality Criteria for Particulate Matter.

    Science.gov (United States)

    National Air Pollution Control Administration (DHEW), Washington, DC.

    To assist states in developing air quality standards, this book offers a review of literature related to atmospheric particulates and the development of criteria for air quality. It not only summarizes the current scientific knowledge of particulate air pollution, but points up the major deficiencies in that knowledge and the need for further…

  19. Externality costs by emission. E. Particulates

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Fossil-fuel-fired electricity generating systems, particularly coal and oil-fired facilities, are significant emitters of particulate matter. The major components of particulate emissions from a power plant include ash, which is made up of heavy metals, radioactive isotopes and hydrocarbons, and sulfates (SO 4 ) and nitrates (NO 3 ), which are formed by reaction of sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ) in the atmosphere. The smallest ash particulates (including sulfates and nitrates) cause human respiratory effects and impaired visibility. Other effects may include materials damage due to soiling and possibly corrosion, damage to domestic and wild flora through deposition of particulates on foliage, and possible health effects on domestic animals and wild fauna. Several studies focus on the direct effects of high ambient levels of small particulates. This chapter reviews the available literature on the effects of particulate emissions on humans and their environment, and attempts to assign a cost figure to the environmental effects and human health impairments associated with particulate matter emissions. Specifically, this report focuses on the effects of particulates related to human health, visibility, flora, fauna and materials

  20. Particulate carbohydrates in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Nandakumar, K.; Venkat, K.

    Particulate matter collected from 77 water samples over a 3000 m water column was analyzed for particulate carbohydrates (PCHO). PCHO in the surface waters ranged from 43 to 143 mu g.l-1, and below 250 m it was 16.PCHO showed large variations at all...

  1. Advanced Fine Particulate Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  2. Particulate filtration in nuclear facilities

    International Nuclear Information System (INIS)

    1991-01-01

    The removal of particulate radioactive material from exhaust air or gases is an essential feature of virtually all nuclear facilities. Recent IAEA publications have covered the broad designs of off-gas and air cleaning systems for the range of nuclear power plants and other facilities. This report is a complementary guidebook that examines in detail the latest developments in the design, operation, maintenance and testing of fibrous air filters. The original draft of the report was prepared by three consultants, M.W. First, of the School of Public Health, Harvard University, United States of America, K.S. Robinson, from the UKAEA Harwell Laboratory, United Kingdom, and H.G. Dillmann, of the Kernforschungzentrum, Karlsruhe, Germany. The Technical Committee Meeting (TCM), at which the report was reviewed and much additional information contributed, was attended by 11 experts and was held in Vienna, from 30 May to 3 June 1988. 64 refs, 41 figs, 10 tabs

  3. Radiant zone heated particulate filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  4. Evaluation of particulate filtration efficiency of retrofit particulate filters for light duty vehicles

    International Nuclear Information System (INIS)

    Van Asch, R.; Verbeek, R.

    2009-10-01

    In the light of the currently running subsidy programme for particulate filters in the Netherlands, the Dutch ministry of spatial planning and environment (VROM) asked TNO to execute a desk study to evaluate the particulates filtration efficiency of retrofit particulate filters for light duty vehicles (passenger cars and vans). The typical retrofit particulate filters for light duty vehicles are also called 'open' or 'half-open' filters, because a part of the exhaust gas can pass through the particulate filter unfiltered. From design point they are very different from the majority of the factory installed particulate filters, which are also called wall-flow or 'closed' particulate filters. Due to these differences there is a large difference in filtration efficiency. Whereas the 'dosed' particulate filters show a filtration efficiency of larger than 90%, the filtration efficiency of 'open' particulate filters is generally lower (type approval minimum 30%), and strongly dependent on the conditions of use. The objective of the current project was to assess the average filtration efficiency of retrofit (open) particulate fillters on light duty vehicles in real world day to day driving, based on available literature data. Also, the reasons of a possible deviation with the type approval test results (minimum filtration efficiency of 30%) was investigated.

  5. Particulate contamination spectrometer. Volume 1: Technical report

    Science.gov (United States)

    Schmitt, R. J.; Boyd, B. A.; Linford, R. M. F.

    1975-01-01

    A laser particulate spectrometer (LPS) system was developed to measure the size and speed distributions of particulate (dusts, aerosols, ice particles, etc.) contaminants. Detection of the particulates was achieved by means of light scattering and extinction effects using a single laser beam to cover a size range of 0.8 to 275 microns diameter and a speed range of 0.2 to 20 meter/second. The LPS system was designed to operate in the high vacuum environment of a space simulation chamber with cold shroud temperatures ranging from 77 to 300 K.

  6. Removal of particulates from nuclear offgas

    International Nuclear Information System (INIS)

    Burchsted, C.A.

    1976-01-01

    Particulate removal from nuclear offgases can be broken down into three parts: pretreatment, prefiltration, and absolute filtration. Pretreatment, using conventional air cleaning devices in most cases, is sometimes required to temper the gases and remove heavy concentrations of particulate matter. Prefiltration, if required, serves primarily to protect the final filter stages from heavy dust loadings in order to extend their life. HEPA filters are the most commonly used ''absolute'' filtration devices and are always required for removal of submicrometer particulates that cannot be removed effectively by other devices

  7. Electrically heated particulate filter enhanced ignition strategy

    Science.gov (United States)

    Gonze, Eugene V; Paratore, Jr., Michael J

    2012-10-23

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating applied to at least one of the PF and the grid. A control module estimates a temperature of the grid and controls the engine to produce a desired exhaust product to increase the temperature of the grid.

  8. Modelling airborne dispersion of coarse particulate material

    International Nuclear Information System (INIS)

    Apsley, D.D.

    1989-03-01

    Methods of modelling the airborne dispersion and deposition of coarse particulates are presented, with the emphasis on the heavy particles identified as possible constituents of releases from damaged AGR fuel. The first part of this report establishes the physical characteristics of the irradiated particulate in airborne emissions from AGR stations. The second part is less specific and describes procedures for extending current dispersion/deposition models to incorporate a coarse particulate component: the adjustment to plume spread parameters, dispersion from elevated sources and dispersion in conjunction with building effects and plume rise. (author)

  9. Particulate Matter (Environmental Health Student Portal)

    Science.gov (United States)

    ... that includes curriculum standards, assessments, and lesson rubrics. Sources of Particulate Matter (U.S. Environmental Protection Agency) - Information and activity on interpreting ... U.S. National Library of Medicine National Institutes of Health U.S. Department ...

  10. Spacecraft Cabin Particulate Monitor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We have built and tested an optical extinction monitor for the detection of spacecraft cabin particulates. This sensor sensitive to particle sizes ranging from a few...

  11. Johns Hopkins Particulate Matter Research Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Johns Hopkins Particulate Matter Research Center will map health risks of PM across the US based on analyses of national databases on air pollution, mortality,...

  12. Diesel Particulate Matter Polygons, California, 2005, NATA

    Data.gov (United States)

    U.S. Environmental Protection Agency — The national-scale assessment includes 177 air pollutants (a subset of the air toxics on the Clean Air Act's list of 187 air toxics plus diesel particulate matter...

  13. Spacecraft Cabin Particulate Monitor, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to design, build and test an optical extinction monitor for the detection of spacecraft cabin particulates. This monitor will be sensitive to particle...

  14. Heat and mass transfer in particulate suspensions

    CERN Document Server

    Michaelides, Efstathios E (Stathis)

    2013-01-01

    Heat and Mass Transfer in Particulate Suspensions is a critical review of the subject of heat and mass transfer related to particulate Suspensions, which include both fluid-particles and fluid-droplet Suspensions. Fundamentals, recent advances and industrial applications are examined. The subject of particulate heat and mass transfer is currently driven by two significant applications: energy transformations –primarily combustion – and heat transfer equipment. The first includes particle and droplet combustion processes in engineering Suspensions as diverse as the Fluidized Bed Reactors (FBR’s) and Internal Combustion Engines (ICE’s). On the heat transfer side, cooling with nanofluids, which include nanoparticles, has attracted a great deal of attention in the last decade both from the fundamental and the applied side and has produced several scientific publications. A monograph that combines the fundamentals of heat transfer with particulates as well as the modern applications of the subject would be...

  15. Allegheny County Particulate Matter 2.5

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The U.S. Environmental Protection Agency provides information on the particulate matter concentration for Allegheny County that have a diameter greater or equal to...

  16. Diesel Particulate Matter Polygons, Hawaii, 2005, NATA

    Data.gov (United States)

    U.S. Environmental Protection Agency — The national-scale assessment includes 177 air pollutants (a subset of the air toxics on the Clean Air Act's list of 187 air toxics plus diesel particulate matter...

  17. Diesel Particulate Matter Polygons, Arizona, 2005, NATA

    Data.gov (United States)

    U.S. Environmental Protection Agency — The national-scale assessment includes 177 air pollutants (a subset of the air toxics on the Clean Air Act's list of 187 air toxics plus diesel particulate matter...

  18. Diesel Particulate Matter Polygons, Nevada, 2005, NATA

    Data.gov (United States)

    U.S. Environmental Protection Agency — The national-scale assessment includes 177 air pollutants (a subset of the air toxics on the Clean Air Act's list of 187 air toxics plus diesel particulate matter...

  19. Analysis of airborne particulate matter

    International Nuclear Information System (INIS)

    Iwatsuki, Masaaki

    2002-01-01

    An airborne particulate matter (APM) consists of many kinds of solid and liquid particles in air. APM analysis methods and the application examples are explained on the basis of paper published after 1998. Books and general remarks, sampling and the measurement of concentration and particle distribution, elemental analysis methods and the present state of analysis of species are introduced. Tapered Element Oscillating Microbalance (TEOM) method can collect continuously the integrating mass, but indicates lower concentration. Cu, Ni, Zn, Co, Fe(2), Mn, Cd, Fe(3) and Pb, the water-soluble elements, are determined by ion-chromatography after ultrasonic extraction of the aqueous solution. The detection limit of them is from 10 to 15 ppb (30 ppb Cd and 60 ppb Pb). The elemental carbon (EC) and organic carbon (OC) are separated by the thermal mass measurement-differential scanning calorimeter by means of keeping at 430degC for 60 min. 11 research organizations compared the results of TC (Total Carbon) and EC by NIOSH method 5040 and the thermal method and obtained agreement of TC. ICP-MS has been developed in order to determine correctly and quickly the trace elements. The determination methods for distinction of chemical forms in the environment were developed. GC/MS, LC/MS and related technologies for determination of organic substances are advanced. Online real-time analysis of APN, an ideal method, is examined. (S.Y.)

  20. Contacting particulate solids with liquids

    International Nuclear Information System (INIS)

    Hodgson, T.D.

    1980-01-01

    Apparatus is described for contacting particulate solids with a fluid. The particular applications described are 1) an acid dissolver for dissolving plutonium from plutonium contaminated ash produced by the incineration of waste such as rubber gloves, tissue paper etc. and 2) apparatus for dissolving gel spheres of nuclear fuel material. The liquid, e.g. acid for use in a leaching process flows through a vertical conduit and past a series of baffles spaced along the axis of the conduit. Each baffle defines a mixing chamber and provides a small gap around its perimeter between the baffle and the wall of the conduit. The baffles are provided with sloping top surfaces for preventing solid particles from settling on the baffles and sloping undersurfaces to improve mixing of the liquid and the solid particles. The liquid flows upwards in the conduit but solid particles may be fed from the top or from the bottom of the conduit to mix with the liquid. Gas may be introduced to promote improved flow conditions. (U.K.)

  1. Particulate emissions from biodiesel fuelled CI engines

    International Nuclear Information System (INIS)

    Agarwal, Avinash Kumar; Gupta, Tarun; Shukla, Pravesh C.; Dhar, Atul

    2015-01-01

    Highlights: • Physical and chemical characterization of biodiesel particulates. • Toxicity of biodiesel particulate due to EC/OC, PAHs and BTEX. • Trace metals and unregulated emissions from biodiesel fuelled diesel engines. • Influence of aftertreatment devices and injection strategy on biodiesel particulates. • Characterization of biodiesel particulate size-number distribution. - Abstract: Compression ignition (CI) engines are the most popular prime-movers for transportation sector as well as for stationary applications. Petroleum reserves are rapidly and continuously depleting at an alarming pace and there is an urgent need to find alternative energy resources to control both, the global warming and the air pollution, which is primarily attributed to combustion of fossil fuels. In last couple of decades, biodiesel has emerged as the most important alternative fuel candidate to mineral diesel. Numerous experimental investigations have confirmed that biodiesel results in improved engine performance, lower emissions, particularly lower particulate mass emissions vis-à-vis mineral diesel and is therefore relatively more environment friendly fuel, being renewable in nature. Environmental and health effects of particulates are not simply dependent on the particulate mass emissions but these change depending upon varying physical and chemical characteristics of particulates. Particulate characteristics are dependent on largely unpredictable interactions between engine technology, after-treatment technology, engine operating conditions as well as fuel and lubricating oil properties. This review paper presents an exhaustive summary of literature on the effect of biodiesel and its blends on exhaust particulate’s physical characteristics (such as particulate mass, particle number-size distribution, particle surface area-size distribution, surface morphology) and chemical characteristics (such as elemental and organic carbon content, speciation of polyaromatic

  2. Participation des médecins généralistes de la province de Benimellal (Maroc) dans le dépistage du cancer du col

    Science.gov (United States)

    Nani, Samira; Benallal, Mohamed; Hassoune, Samira; Kissi, Dounia; Maaroufi, Abderrahmane

    2013-01-01

    Introduction Au Maroc, chaque année il y aurait environ 2000 nouveaux cas de cancer du col et les 2/3 des cas sont pris en charge à un stade très avancé. Nous avons mené une étude transversale, exhaustive incluant les 71 médecins généralistes exerçant dans les établissements de soins de santé de base du secteur public et privé de la province de Benimellal. Le but était d’évaluer leurs connaissances et leur participation au dépistage du cancer du col. Méthodes Nous avons mené une étude transversale, exhaustive incluant les 71 médecins généralistes exerçant dans les établissements de soins de santé de base du secteur public et privé de la province de Benimellal. Le but était d’évaluer leurs connaissances et leur participation au dépistage du cancer du col. Résultats Le niveau de connaissance était relativement modeste, 22 médecins généraliste avaient répondu à la question sur l'incidence du cancer du col au Maroc, Parmi eux (81,8%) avaient donné une réponse incorrecte. L'Herpes Papilloma virus comme facteur de risque du cancer du col a été identifié par seulement 21% des médecins généralistes. La participation au dépistage était également défaillante, 92,8% n'avaient jamais pratiqué le FCV chez leurs patientes à cause principalement du manque de formation (95,5%). Conclusion Les résultats montrent la nécessité d'améliorer les connaissances théoriques et pratique des médecins généralistes concernant le dépistage du cancer du col. PMID:23785557

  3. Etude de la qualité bactériologique de l’eau utilisée dans l’industrie agroalimentaire dans le Nord du Maroc

    Science.gov (United States)

    Haijoubi, El Houcine; Benyahya, Fatiha; Bendahou, Abdrezzak; Essadqui, Faima Zahra; Behhari, Mohammed El; El Mamoune, Ahmed Fouad; Ghailani, Naima Nourouti; Mechita, Mohcine Bennani; Barakat, Amina

    2017-01-01

    Introduction L'eau est utilisée d'une façon primordiale dans tout le processus de la fabrication des produits alimentaires. Les industries agroalimentaires du Nord du Maroc utilisent différentes sources d'eaux mais l'eau de réseau public et l'eau de puits sont les principales sources d'eau utilisée. Cette eau peut s'avérer la source principale des éventuelles contaminations et altérations des aliments. Notre but est d'évaluer la qualité bactériologique de l'eau utilisée par les industries agroalimentaires dans la région du Nord du Maroc, d'identifier les différents germes responsables de la pollution de ces eaux et de définir les principales causes de cette pollution. Méthodes Des échantillons d'eau prélevés aux robinets ou des puits ont été analysés pour la recherche des germes indicateurs de la pollution (coliformes totaux (CT), coliformes fécaux (CF), entérocoques intestinaux (E), microorganismes revivifiables (MOR), anaérobies sulfitoréducteurs) et les germes pathogènes (Salmonelles, Staphylocoques, Pseudomonas aeruginosa). Le dénombrement des bactéries a été fait par la technique de filtration et par incorporation en milieu solide en surfusion. Résultats Les résultats ont montré que les eaux du réseau public ont été de qualité bactériologique satisfaisante tandis que 40% des eaux des puits ont été non conformes aux normes à cause de la présence des indicateurs de pollution CT, CF, E et MOR. En revanche, les germes pathogènes, en particulier les Salmonelles, ont été absents dans les eaux de tous les puits analysés. Conclusion La pollution de ces puits a été généralement liée au non-respect des conditions de puisage hygiéniques. La qualité bactériologique des eaux de ces puits peut être améliorée par une protection adéquate. PMID:28450992

  4. Homogenized thermal conduction model for particulate foods

    OpenAIRE

    Chinesta , Francisco; Torres , Rafael; Ramón , Antonio; Rodrigo , Mari Carmen; Rodrigo , Miguel

    2002-01-01

    International audience; This paper deals with the definition of an equivalent thermal conductivity for particulate foods. An homogenized thermal model is used to asses the effect of particulate spatial distribution and differences in thermal conductivities. We prove that the spatial average of the conductivity can be used in an homogenized heat transfer model if the conductivity differences among the food components are not very large, usually the highest conductivity ratio between the foods ...

  5. Complexity analysis in particulate matter measurements

    Directory of Open Access Journals (Sweden)

    Luciano Telesca

    2011-09-01

    Full Text Available We investigated the complex temporal fluctuations of particulate matter data recorded in London area by using the Fisher-Shannon (FS information plane. In the FS plane the PM10 and PM2.5 data are aggregated in two different clusters, characterized by different degrees of order and organization. This results could be related to different sources of the particulate matter.

  6. La problématique du coût des nouvelles thérapeutiques en oncologie: qu'en-est-il du Maroc?

    Science.gov (United States)

    Brahmi, Sami Aziz; Zahra, Ziani Fatima; Seddik, Youssef; Afqir, Said

    2016-01-01

    Le cancer est un problème majeur de santé public en Afrique. Les progrès réalisé dans le traitement des cancers ces dix dernières années est indéniable. L’émergence des thérapies ciblés en oncologie a permit de modifier l'histoire naturelle de certains cancers réputés de mauvais pronostic. En dépit de leurs efficacité, ces thérapeutiques pose un problème majeur de coût qui les rend inaccessible à la majorité des patients dans les pays en voie développement. Au Maroc, le cancer est reconnu comme a une affection de longue durée et les patients bénéficient de ce fait d'une couverture médicale totale. L'implication de la société civile a permis aussi d'améliorer la prise en charge ainsi qu'un accès plus élargi aux médicaments innovants pour les patients les plus démunis. PMID:27642392

  7. Small-angle light scattering by airborne particulates: Environnement S.A. continuous particulate monitor

    International Nuclear Information System (INIS)

    Renard, Jean-Baptiste; Gaubicher, Bertrand; Thaury, Claire; Mineau, Jean-Luc

    2010-01-01

    Airborne particulate matter may have an effect on human health. It is therefore necessary to determine and control in real time the evolution of the concentration and mass of particulates in the ambient air. These parameters can be obtained using optical methods. We propose here a new instrument, 'CPM' (continuous particulate monitor), for the measurement of light scattered by ambient particulates at small angles. This geometry allows simultaneous and separate detections of PM10, PM2.5 and PM1 fractions of airborne particulate matter, with no influence of their chemical nature and without using theoretical calculations. The ambient air is collected through a standard sampling head (PM10 inlet according to EN 12341, PM2.5 inlet according to EN 14907; or PM1, TSP inlets, standard US EPA inlets). The analysis of the first measurements demonstrates that this new instrument can detect, for each of the seven defined size ranges, real-time variations of particulate content in the ambient air. The measured concentrations (expressed in number per liter) can be converted into total mass concentrations (expressed in micrograms per cubic meter) of all fractions of airborne particulate matters sampled by the system. Periodic comparison with a beta-attenuation mass monitor (MP101M Beta Gauge Analyzer from Environnement S.A. company) allows the calculation of a calibration factor as a function of the mean particulate density that is used for this conversion. It is then possible to provide real-time relative variations of aerosol mass concentration

  8. Temporal and spatial variations in particulate matter, particulate organic carbon and attenuation coefficient in Cochin Backwaters

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, K.S.

    Nine stations over a stretch of 21 km of Periyar river estuary were sampled during January to December 1981. Particulate matter varied from 3-253 mg.1 super(1) at the surface and 24.8-257mg.1 super(1) at the bottom. Particulate organic carbon ranged...

  9. On the Impact of Particulate Matter Distribution on Pressure Drop of Wall-Flow Particulate Filters

    Directory of Open Access Journals (Sweden)

    Vicente Bermúdez

    2017-03-01

    Full Text Available Wall-flow particulate filters are a required exhaust aftertreatment system to abate particulate matter emissions and meet current and incoming regulations applying worldwide to new generations of diesel and gasoline internal combustion engines. Despite the high filtration efficiency covering the whole range of emitted particle sizes, the porous substrate constitutes a flow restriction especially relevant as particulate matter, both soot and ash, is collected. The dependence of the resulting pressure drop, and hence the fuel consumption penalty, on the particulate matter distribution along the inlet channels is discussed in this paper taking as reference experimental data obtained in water injection tests before the particulate filter. This technique is demonstrated to reduce the particulate filter pressure drop without negative effects on filtration performance. In order to justify these experimental data, the characteristics of the particulate layer are diagnosed applying modeling techniques. Different soot mass distributions along the inlet channels are analyzed combined with porosity change to assess the new properties after water injection. Their influence on the subsequent soot loading process and regeneration is assessed. The results evidence the main mechanisms of the water injection at the filter inlet to reduce pressure drop and boost the interest for control strategies able to force the re-entrainment of most of the particulate matter towards the inlet channels’ end.

  10. Advanced Hybrid Particulate Collector Project Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.J.

    1995-11-01

    As the consumption of energy increases, its impact on ambient air quality has become a significant concern. Recent studies indicate that fine particles from coal combustion cause health problems as well as atmospheric visibility impairment. These problems are further compounded by the concentration of hazardous trace elements such as mercury, cadmium, selenium, and arsenic in fine particles. Therefore, a current need exists to develop superior, but economical, methods to control emissions of fine particles. Since most of the toxic metals present in coal will be in particulate form, a high level of fine- particle collection appears to be the best method of overall air toxics control. However, over 50% of mercury and a portion of selenium emissions are in vapor form and cannot be collected in particulate control devices. Therefore, this project will focus on developing technology not only to provide ultrahigh collection efficiency of particulate air toxic emissions, but also to capture vapor- phase trace metals such as mercury and selenium. Currently, the primary state-of-the-art technologies for particulate control are fabric filters (baghouses) and electrostatic precipitators (ESPs). However, they both have limitations that prevent them from achieving ultrahigh collection of fine particulate matter and vapor-phase trace metals. The objective of this project is to develop a highly reliable advanced hybrid particulate collector (AHPC) that can provide > 99.99 % particulate collection efficiency for all particle sizes between 0.01 and 50 14m, is applicable for use with all U.S. coals, and is cost-0443competitive with existing technologies. Phase I of the project is organized into three tasks: Task I - Project Management, Reporting, and Subcontract Consulting Task 2 - Modeling, Design, and Construction of 200-acfm AHPC Model Task 3 - Experimental Testing and Subcontract Consulting

  11. The mechanical behaviour of packed particulates

    International Nuclear Information System (INIS)

    Dutton, R.

    1998-01-01

    Within the Canadian Nuclear Fuel Waste Management program, the central concept is to package used fuel in containers that would be deposited in an underground vault in a plutonic rock formation. To provide internal mechanical support for the container, the reference design specifies it to be filled with a matrix of compacted particulate material (called 'packed particulate'), such as quartz sand granules. The focus of this report is on the mechanical properties of the packed-particulate material, based on information drawn from the extant literature. We first consider the packing density of particulate matrices to minimize the remnant porosity and maximize mechanical stability under conditions of external pressure. Practical methods, involving vibratory packing, are reviewed and recommendations made to select techniques to achieve optimum packing density. The behaviour of particulates under compressive loading has been of interest to the powder metallurgy industry (i.e., the manufacture of products from pressed/sintered metal and ceramic powders) since the early decades of this century. We review the evidence showing that in short timescales, stress induced compaction occurs by particle shuffling and rearrangement, elastic distortion, plastic yielding and microfracturing. Analytical expressions are available to describe these processes in a semiquantitative fashion. Time-dependent compaction, mainly via creep mechanisms, is more complex. Much of the theoretical and experimental information is confined to higher temperatures (> 500 degrees C), where deformation rates are more rapid. Thus, for the relatively low ambient temperatures of the waste container (∼100 degrees C), we require analytical techniques to extrapolate the collective particulate creep behaviour. This is largely accomplished by employing current theories of creep deformation, particularly in the form of Deformation Mechanism Maps, which allow estimation of creep rates over a wide range of stress

  12. The mechanical behaviour of packed particulates

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, R

    1998-01-01

    Within the Canadian Nuclear Fuel Waste Management program, the central concept is to package used fuel in containers that would be deposited in an underground vault in a plutonic rock formation. To provide internal mechanical support for the container, the reference design specifies it to be filled with a matrix of compacted particulate material (called 'packed particulate'), such as quartz sand granules. The focus of this report is on the mechanical properties of the packed-particulate material, based on information drawn from the extant literature. We first consider the packing density of particulate matrices to minimize the remnant porosity and maximize mechanical stability under conditions of external pressure. Practical methods, involving vibratory packing, are reviewed and recommendations made to select techniques to achieve optimum packing density. The behaviour of particulates under compressive loading has been of interest to the powder metallurgy industry (i.e., the manufacture of products from pressed/sintered metal and ceramic powders) since the early decades of this century. We review the evidence showing that in short timescales, stress induced compaction occurs by particle shuffling and rearrangement, elastic distortion, plastic yielding and microfracturing. Analytical expressions are available to describe these processes in a semiquantitative fashion. Time-dependent compaction, mainly via creep mechanisms, is more complex. Much of the theoretical and experimental information is confined to higher temperatures (> 500 degrees C), where deformation rates are more rapid. Thus, for the relatively low ambient temperatures of the waste container ({approx}100 degrees C), we require analytical techniques to extrapolate the collective particulate creep behaviour. This is largely accomplished by employing current theories of creep deformation, particularly in the form of Deformation Mechanism Maps, which allow estimation of creep rates over a wide

  13. Mouline Nabil, Le califat imaginaire d’Ahmad al-Mansûr. Pouvoir et diplomatie au Maroc au xvie siècle, PUF, Proche-Orient, Paris, 2009, 371 p.

    Directory of Open Access Journals (Sweden)

    Halima Ferhat

    2010-09-01

    Full Text Available Au lendemain de la bataille des Trois Rois, plus connue au Maroc sous le nom de Ouad al Makhazin, de redoutables acteurs s’affrontent : les Habsbourgs d’Espagne et leurs ennemis protestants aux Pays Bas, l’Angleterre, le Portugal dont l’autonomie est désormais remise en question, ainsi que de multiples petits princes locaux et les maîtres des zaouyas sans oublier les corsaires qui, il faut le rappeler, forment un réseau qui n’est pas toujours à l’ordre d’un pays. Plusieurs excellents livres r...

  14. Document de base d'un nouveau projet régional : Réduction des émissions de polluants dans le secteur du transport dans trois pays du Maghreb (Algérie, Maroc, Tunisie)

    OpenAIRE

    Joumard , Robert; BOUGHEDAOUI , Ménouèr

    2003-01-01

    présenté lors du Forum régional sur les changements climatiques, Les pays du Maghreb face aux changements climatiques : bilan et perspectives (Algérie, Maroc, Tunisie), Marrakech, 27-28 mars 2003; Pour répondre à une demande croissante de la mobilité des personnes et des marchandises, le transport routier évolue rapidement alors que les infrastructures, la réglementation et plus généralement les politiques n'intègrent guère la problématique de réduction des gaz polluants et à effet de serre, ...

  15. Migration of particulates in permeable rock columns

    International Nuclear Information System (INIS)

    Cropper, R.L.

    1982-01-01

    The migration of radioactive material through soil and permeable rock formations have become a major topic of concern due to the interest in the licensing of new radioactive waste disposal sites. Previously, research has been conducted in relation to deep repositories; however, similar situations arise in the vadose zone, where there is a higher probability of naturally-occurring particulates of organic nature and for the incursion of water. Test data has provided information which suggests that particulates will travel through porous media subject to various delay mechnisms and must be included in any consideration of waste migration. Data concerning particulate migration must and should be considered in the future when radioactive waste disposal sites are licensed

  16. Particulate Matter Emission Factors for Biomass Combustion

    Directory of Open Access Journals (Sweden)

    Simone Simões Amaral

    2016-10-01

    Full Text Available Emission factor is a relative measure and can be used to estimate emissions from multiple sources of air pollution. For this reason, data from literature on particulate matter emission factors from different types of biomass were evaluated in this paper. Initially, the main sources of particles were described, as well as relevant concepts associated with particle measurements. In addition, articles about particle emissions were classified and described in relation to the sampling environment (open or closed and type of burned biomass (agricultural, garden, forest, and dung. Based on this analysis, a set of emission factors was presented and discussed. Important observations were made about the main emission sources of particulate matter. Combustion of compacted biomass resulted in lower particulate emission factors. PM2.5 emissions were predominant in the burning of forest biomass. Emission factors were more elevated in laboratory burning, followed by burns in the field, residences and combustors.

  17. Particulate hot gas stream cleanup technical issues

    Energy Technology Data Exchange (ETDEWEB)

    Pontius, D.H.; Snyder, T.R.

    1999-09-30

    The analyses of hot gas stream cleanup particulate samples and descriptions of filter performance studied under this contract were designed to address problems with filter operation that have been linked to characteristics of the collected particulate matter. One objective of this work was to generate an interactive, computerized data bank of the key physical and chemical characteristics of ash and char collected from operating advanced particle filters and to relate these characteristics to the operation and performance of these filters. The interactive data bank summarizes analyses of over 160 ash and char samples from fifteen pressurized fluidized-bed combustion and gasification facilities utilizing high-temperature, high pressure barrier filters.

  18. Gel nano-particulates against radioactivity

    International Nuclear Information System (INIS)

    Deroin, Ph.

    2004-01-01

    The Argonne research center (USA) has developed a 'super-gel' compound, a polymer close to those used in baby's diapers, which can reach a 90% efficiency in the radioactive decontamination of porous materials, like bricks or concrete. The contaminated materials are sprayed with a mixture of polymer gel and wetting agent with nano-particulates in suspension. Under the action of the wetting agent, radioactivity migrates from the pores to the gel and is trapped by the nano-particulates. The drying and recycling of the gel allows to reduce the volume of radioactive wastes. Short paper. (J.S.)

  19. Particulate matter sensor with a heater

    Science.gov (United States)

    Hall, Matthew [Austin, TX

    2011-08-16

    An apparatus to detect particulate matter. The apparatus includes a sensor electrode, a shroud, and a heater. The electrode measures a chemical composition within an exhaust stream. The shroud surrounds at least a portion of the sensor electrode, exclusive of a distal end of the sensor electrode exposed to the exhaust stream. The shroud defines an air gap between the sensor electrode and the shroud and an opening toward the distal end of the sensor electrode. The heater is mounted relative to the sensor electrode. The heater burns off particulate matter in the air gap between the sensor electrode and the shroud.

  20. Risque de réémergence du paludisme au Maroc Étude de la capacité vectorielle d’Anopheles labranchiae dans une zone rizicole au nord du pays

    Directory of Open Access Journals (Sweden)

    Faraj C.

    2008-12-01

    Full Text Available Dans le but d’estimer le risque de réintroduction du paludisme au Maroc, nous avons analysé le potentiel paludogène d’une zone rizicole au nord du pays. Nos résultats ont montré que la capacité vectorielle d’An. labranchiae, vecteur du paludisme au Maroc, était particulièrement élevée pendant la période estivale qui correspond à la période de culture du riz. Le risque d’une reprise de la transmission du paludisme autochtone est élevé du fait de l’éventuelle présence de porteurs de parasite dans le dernier foyer de paludisme limitrophe de la zone d’étude. Le risque d’une introduction du paludisme tropical est faible, vu la faible vulnérabilité de la région et la compétence de ses vecteurs, considérée comme faible. Toutefois, ce risque doit faire l’objet d’une grande attention.

  1. Aerotrace. Measurement of particulates from an engine combustor

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, C D [DRA, Farnborough (United Kingdom)

    1998-12-31

    The effect of gas turbine operating conditions, inlet temperature, pressure and overall air fuel ratio, on particulate number density has been measured. Particulate number density was found to be proportional to combustor inlet pressure and decrease with increasing combustor inlet temperature. The relationship with air fuel ratio is more complex. The mechanism of particulate loss down sample lines has been elucidated and equations are presented to predict particulate losses for stainless steel and PTFE sample lines. (author) 3 refs.

  2. Aerotrace. Measurement of particulates from an engine combustor

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, C.D. [DRA, Farnborough (United Kingdom)

    1997-12-31

    The effect of gas turbine operating conditions, inlet temperature, pressure and overall air fuel ratio, on particulate number density has been measured. Particulate number density was found to be proportional to combustor inlet pressure and decrease with increasing combustor inlet temperature. The relationship with air fuel ratio is more complex. The mechanism of particulate loss down sample lines has been elucidated and equations are presented to predict particulate losses for stainless steel and PTFE sample lines. (author) 3 refs.

  3. Atmospheric trace metal concentrations in Suspended Particulate ...

    African Journals Online (AJOL)

    The air particulate samples were collected from the kitchens, living rooms and outdoor environment of five households in the community. The quantification of the trace metals was done using Atomic Absorption spectrometry method, employing HNO based wet digestion. High baseline concentration of SPMwere obtained ...

  4. Effect of condensable species on particulate fouling

    NARCIS (Netherlands)

    Sathyanarayanarao Subbarao, K.K.; Rindt, C.C.M.; Steenhoven, van A.A.; Malayeri, M.R.; Muller-Steinhagen, H.; Watkinson, A.P.

    2011-01-01

    The flue gases emanating from the combustion of fuels or gasification process invariably comprises particulate matter and many chemical species in vapor form. The temperature of the flue gases gradually reduces when passing through different sections of heat exchanger like superheater, evaporator

  5. Effect of condensable species on particulate fouling

    NARCIS (Netherlands)

    Sathyanarayanarao Subbarao, K.K.; Rindt, C.C.M.; Steenhoven, van A.A.

    2013-01-01

    The flue gases emanating from the combustion of fuels or gasification process invariably comprise particulate matter and many chemical species in vapor form. The temperature of the flue gases gradually reduces when passing through different sections of heat exchanger, such as the superheater,

  6. Evaluation of diesel particulate matter sampling techniques

    CSIR Research Space (South Africa)

    Pretorius, CJ

    2011-09-01

    Full Text Available The study evaluated diesel particulate matter (DPM) sampling methods used in the South African mining industry. The three-piece cassette respirable, open face and stopper sampling methods were compared with the SKC DPM cassette method to find a...

  7. Casting of particulate Al-base composites

    International Nuclear Information System (INIS)

    Moustafa, S.F.

    1997-01-01

    A molten Al-4 wt.% Cu as well as a Al-13 wt.% Si alloy have been mixed mechanically with particulate of SiC, Al 2 O 3 , or graphite. After the completion of mixing, each mixture was poured into a permanent mould to solidify. To overcome the problem of non-wettability that exists between the investigated particulate and the molten aluminum alloys the particulate was chemically treated by impregnation in a solution containing Na + ions. The loading of SiC or Al 2 O 3 particulate in the produced composites can be as high as 40 wt.%, and for graphite particles it can be 20 wt.%. The mixing time required to introduce and distribute the investigated particles into the molten matrix was as low as five minutes to recluce chemical reactions at the interfaces between them. Processing details and parameters controlling this technique are described. Metallographic examinations as well as tensile tests were carried out to characterize the microstructure, the distribution of the particles and the strength of these composites. The results display that the composites made by this technique have good microstructure and tensile properties. (orig.)

  8. Glints from particulate media and wavy surfaces

    International Nuclear Information System (INIS)

    Borovoi, Anatoli; Konoshonkin, Alexander; Kolokolova, Ludmilla

    2012-01-01

    Glints are bright light spots created by particulate media like cirrus clouds, glaciers, and wavy water surfaces. They are seen around the specular reflection angle. In this paper, the glints from such scattering/reflecting media are described in a unified manner through the probability density for facet tilts. Various kinds of these probability densities for wavy surfaces are defined and classified. The concept of the differential scattering cross section (DSCS) for rough surfaces instead of the conventional bidirectional reflectance distribution function (BRDF) is introduced for characterization of the glints. The simple equations connecting the DSCS and the probability densities for facet tilts are derived. It is shown that the glints from particulate media and wavy surface are very similar at small incidence angles and they are significantly different at slant incidence. -- Highlights: ► Differential scattering cross section unifies particulate media and wavy surfaces. ► The glint pattern is a mapping of the probability density function for facet tilts. ► Shadowing is a crucial aspect of glint pattern formation. ► Glint patterns discriminate between the particulate media and wavy surfaces.

  9. Particulate absorption properties in the Red Sea from hyperspectral particulate absorption spectra

    KAUST Repository

    Tiwari, Surya Prakash; Zarokanellos, Nikolaos; Kheireddine, Malika; Shanmugam, Palanisamy; Jones, Burton

    2018-01-01

    This paper aims to describe the variability of particulate absorption properties using a unique hyperspectral dataset collected in the Red Sea as part of the TARA Oceans expedition. The absorption contributions by phytoplankton (aph) and non

  10. L'Anti-Atlas occidental du Maroc: étude sédimentologique et reconstitutions paléogéographiques au Cambrien inférieur

    Science.gov (United States)

    Benssaou, M.; Hamoumi, N.

    2001-04-01

    L'étude lithostratigraphique en sédimentologique des formations du Cambrien inférieur de l'Anti-Atlas occidental (Maroc) a permis de mettre en évidence la diversité extrême des faciès allant des faciès continentaux jusqu'au faciès franchement marins. La répartition verticale de ces faciès ainsi que leurs associations ont permis de (i) proposer un nouveau découpage de la succession en formations lithostratigraphiques, (ii) reconstituer les milieux de dépôt (système fluviatile, lacs, fan-deltas, milieu littoral, plate-forme dominée par des constructions stromatolitiques et récifales et plate-forme dominée par les tempêtes) et (iii) établir des modèles paléogéographiques retraçant les différentes étapes d'évolution de ce bassin qui fait partie de la plate-forme nord-gondwanienne au Cambrien inférieur. Lithostratigraphical and sedimentological studies of the Early Cambrian formations in the western Anti-Atlas (Morocco) evidence their large diversity of facies ranging from continental to clearly marine. Vertical distribution and associations of facies afford opportunities to (i) suggest a new classification of the sedimentary sequence in terms of lithostratigraphic formations, (ii) restore the depositional environments (fluvial system, lake, delta fan, coast, stromatolite and reef-dominated platform, tempest-dominated platform), and (iii) establish palæogeographic models displaying the different evolutionary stages of this basin that constituted a part of the Lower Cambrian north-Gondwanian platform.

  11. 40 CFR 230.21 - Suspended particulates/turbidity.

    Science.gov (United States)

    2010-07-01

    ... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.21 Suspended particulates/turbidity. (a) Suspended particulates in the aquatic ecosystem consist of fine-grained mineral particles..., and man's activities including dredging and filling. Particulates may remain suspended in the water...

  12. Urban tree effects on fine particulate matter and human health

    Science.gov (United States)

    David J. Nowak

    2014-01-01

    Overall, city trees reduce particulate matter and provide substantial health benefits; but under certain conditions, they can locally increase particulate matter concentrations. Urban foresters need to understand how trees affect particulate matter so they can select proper species and create appropriate designs to improve air quality. This article details trees'...

  13. Note on the sanitary impact of diesel particulates; Note sur l'impact sanitaire des particules diesel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-10-15

    In the actual situation of scientific works, the epidemiology studies on environment do not allow to say the carcinogen contribution of diesel particulates at the concentration levels measured in the urban air. But according to the experimental data for the rat and the data observed for the personnel exposed to diesel particulates these particulates are classified as probably carcinogen. (N.C.)

  14. NICKEL SPECIATION OF URBAN PARTICULATE MATTER

    Energy Technology Data Exchange (ETDEWEB)

    Kevin C. Galbreath; Charlene R. Crocker; Carolyn M. Nyberg; Frank E. Huggins; Gerald P. Huffman

    2003-10-01

    A four-step sequential Ni extraction method, summarized in Table AB-1, was evaluated for identifying and quantifying the Ni species occurring in urban total suspended particulate (TSP) matter and fine particulate matter (<10 {micro}m [PM{sub 10}] and <2.5 {micro}m [PM{sub 2.5}] in aerodynamic diameter). The extraction method was originally developed for quantifying soluble, sulfidic, elemental, and oxidic forms of Ni that may occur in industrial atmospheres. X-ray diffraction (XRD) and x-ray absorption fine structure (XAFS) spectroscopy were used to evaluate the Ni species selectivity of the extraction method. Uncertainties in the chemical speciation of Ni in urban PM{sub 10} and PM{sub 2.5} greatly affect inhalation health risk estimates, primarily because of the large variability in acute, chronic, and cancer-causing effects for different Ni compounds.

  15. Particulate photocatalysts for overall water splitting

    Science.gov (United States)

    Chen, Shanshan; Takata, Tsuyoshi; Domen, Kazunari

    2017-10-01

    The conversion of solar energy to chemical energy is a promising way of generating renewable energy. Hydrogen production by means of water splitting over semiconductor photocatalysts is a simple, cost-effective approach to large-scale solar hydrogen synthesis. Since the discovery of the Honda-Fujishima effect, considerable progress has been made in this field, and numerous photocatalytic materials and water-splitting systems have been developed. In this Review, we summarize existing water-splitting systems based on particulate photocatalysts, focusing on the main components: light-harvesting semiconductors and co-catalysts. The essential design principles of the materials employed for overall water-splitting systems based on one-step and two-step photoexcitation are also discussed, concentrating on three elementary processes: photoabsorption, charge transfer and surface catalytic reactions. Finally, we outline challenges and potential advances associated with solar water splitting by particulate photocatalysts for future commercial applications.

  16. DESIGN OF PARTICULATE MATERIAL COMPACTOR ROLLS DIAMETER

    Directory of Open Access Journals (Sweden)

    Peter Peciar

    2017-09-01

    Full Text Available At present, in a period of an industrial expansion great emphasis is placed on the environment. That means aiming for a reduced energy consumption, and also lessening dustiness from very fine powder material. This category also includes particulate material agglomeration processes. Because this process is very energy-intensive, it is necessary to correctly design these devices. The aim of this paper is to focus on a theoretical design of a production compactor with the rolls diameter for an experimental particulate material, based on Johanson’s theory and experimentally measured material properties. The material used for experimental measurements was an NPK-based industrial fertilizer consisting of several components. The results of this paper is the dependence of the ratio of the maximum compression pressure to the initial compression pressure from the rolls diameter of the proposed compactor.

  17. Vertical hydraulic transport of particulate solids

    International Nuclear Information System (INIS)

    Restini, C.V.; Massarani, G.

    1977-01-01

    The problem of particulate solid vertical transport is formulated using the conservation equations of Continuum Mechanics. It is shown that the constitutive equation for solid-fluid interaction term in the equations of motion may be determined by rather simple experiments of homogeneous fluidization. The predicted fluid pressure drop and solid concentration are in satisfacting agreement with past experiments and with data obtained in this work. (Author) [pt

  18. Polarimetric Remote Sensing of Atmospheric Particulate Pollutants

    Science.gov (United States)

    Li, Z.; Zhang, Y.; Hong, J.

    2018-04-01

    Atmospheric particulate pollutants not only reduce atmospheric visibility, change the energy balance of the troposphere, but also affect human and vegetation health. For monitoring the particulate pollutants, we establish and develop a series of inversion algorithms based on polarimetric remote sensing technology which has unique advantages in dealing with atmospheric particulates. A solution is pointed out to estimate the near surface PM2.5 mass concentrations from full remote sensing measurements including polarimetric, active and infrared remote sensing technologies. It is found that the mean relative error of PM2.5 retrieved by full remote sensing measurements is 35.5 % in the case of October 5th 2013, improved to a certain degree compared to previous studies. A systematic comparison with the ground-based observations further indicates the effectiveness of the inversion algorithm and reliability of results. A new generation of polarized sensors (DPC and PCF), whose observation can support these algorithms, will be onboard GF series satellites and launched by China in the near future.

  19. POLARIMETRIC REMOTE SENSING OF ATMOSPHERIC PARTICULATE POLLUTANTS

    Directory of Open Access Journals (Sweden)

    Z. Li

    2018-04-01

    Full Text Available Atmospheric particulate pollutants not only reduce atmospheric visibility, change the energy balance of the troposphere, but also affect human and vegetation health. For monitoring the particulate pollutants, we establish and develop a series of inversion algorithms based on polarimetric remote sensing technology which has unique advantages in dealing with atmospheric particulates. A solution is pointed out to estimate the near surface PM2.5 mass concentrations from full remote sensing measurements including polarimetric, active and infrared remote sensing technologies. It is found that the mean relative error of PM2.5 retrieved by full remote sensing measurements is 35.5 % in the case of October 5th 2013, improved to a certain degree compared to previous studies. A systematic comparison with the ground-based observations further indicates the effectiveness of the inversion algorithm and reliability of results. A new generation of polarized sensors (DPC and PCF, whose observation can support these algorithms, will be onboard GF series satellites and launched by China in the near future.

  20. L'univers des particules une introduction

    CERN Document Server

    Diu, Bernard

    2017-01-01

    Au début du XXe siècle, les scientifiques imaginaient que l'ensemble du monde était construit à partir de trois "particules élémentaires" (électron, proton, photon). Depuis, nous avons appris que notre univers contient un nombre considérable de particules - soit des corps individualisés d'extension réduite - de natures et de caractéristiques très diverses, qu'il serait illusoire de chercher à énumérer de manière formelle et systématique. C'est pourquoi le propos de ce livre suit une stratégie fondamentalement différente. Il s'organise autour de certaines propriétés générales que laissent apparaître l'observation et l'étude des particules dans leur existence et leur conduite primaire. Aussi, chacune des parties de cet ouvrage rassemble plusieurs chapitres de thèmes voisins, mais un sujet donné peut également être traité en divers endroits et, de ce fait, être abordé sous différents angles de manière complémentaire. De telles compositions et décompositions d'éléments proche...

  1. Sampling/classification of gasifier particulates

    International Nuclear Information System (INIS)

    Wegrzyn, J.

    1984-01-01

    A high temperature and pressure real time extractive sampling probe for particulate monitoring was built at Brookhaven National Laboratory and tested on Morgantown Energy Technology Center's 42 inch fixed bed gasifier. The probe was specifically designed for the conditions of highly loaded particulate and condensable streams, that exist at the outlet of a fixed bed gasifier. Some of the salient features of the probe are: porous tube gas injection, aerodynamic particle classification in the presence of condensable vapors, β gauge particle detection, and micro processor control. Three of the key design problems were the separation of the particles from the vapor without promoting condensation, the prevention of plugging, and real time monitoring. Some plugging did occur over the seven day sampling period, but by over pressurizing and back purging the clog was blown back into the process stream. The tests validate the proof of concept of the sampling probe and indicated that the particulate output from the bed came in the form of bursts (several minutes in duration) rather than in the form of a steady stream

  2. Radio Frequency Sensing of Particulate Matter Accumulation on a Gasoline Particulate Filter

    Energy Technology Data Exchange (ETDEWEB)

    Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL; Sappok, Alex [Filter Sensing Technologies; Ragaller, Paul [Filter Sensing Technologies; Bromberg, L. [Massachusetts Institute of Technology (MIT)

    2016-10-30

    Filter Sensing Technology’s radio frequency (RF) sensor for particulate filter on-board diagnostics (OBD) was studied on a lean gasoline engine at the National Transportation Research Center (NTRC) at Oak Ridge National Laboratory (ORNL). The response of the RF sensor to particulate matter (PM) or “soot” accumulation on the gasoline particulate filter (GPF) installed in the engine exhaust was evaluated. In addition, end plugs of the GPF were purposely removed, and subsequent changes to the RF sensor measured soot loading on the GPF were characterized. Results from the study showed that the RF sensor can accurately measure soot accumulation on a GPF; furthermore, the predicted decreased soot accumulation due to plug removal was detected by the RF sensor. Overall, the studies were short and preliminary in nature; however, clearly, the RF sensor demonstrated the capability of measuring GPF soot loading at a level suitable for use in lean gasoline engine emission control OBD and control.

  3. Analyse Pharmaceutique de la prescription des antibiotiques au service des brules et chirurgie plastique de l'Hopital Militaire d'Instruction Mohammed V, Maroc

    Science.gov (United States)

    Benziane, H.; Karfo, R.; Siah, S.; Taoufik, J.

    2011-01-01

    Summary L'infection est longtemps restée la principale cause de mortalité chez le brûlé grave. Ce travail a pour but d'évaluer la prescription des antibiotiques dans notre Service des Brûlés et Chirurgie Plastique, au regard du dossier d'autorisation de mise sur le marché (Résumé des caractéristiques du produit). Tous les patients sous antibiothérapie, au Service des Brûlés et Chirurgie Plastique de l'Hôpital Militaire d'Instruction Mohammed V de Rabat, Maroc, durant la période janvier 2008/mai 2009, ont été inclus. Il s'agit d'une étude rétrospective qui a analysé 41 dossiers de patients. Les antibiotiques utilisés par le service appartiennent à différentes familles. Les plus utilisés sont les bêta-lactamines (65%), glycopeptides (10,5%), aminosides (9%), quinolones (7%) et colistine (4,3%), avec 4,2% pour les autres classes d'antibiotiques (métronidazole 500 mg en perfusion, fluconazole injectable 100 mg/50 ml, rifampicine 600 mg en perfusion, sulfadiazine argentique crème, acide fusidique 2% crème, etc.); 70% des prescriptions sont non documentées. La voie injectable est prépondérante (89%). En tout, 227 ordonnances nominatives d'antibiothérapie ont été analysées: la posologie et les contre-indications ont été respectées par rapport à l'autorisation de mise sur le marché. Trois cas d'interactions médicamenteuses ont été relevés (fluconazole-rifampicine, fluconazole-Saccharomyces boulardii, amikacine-vancomycine). Ce constat montre l'importance de l'analyse pharmaceutique des prescriptions des antibiotiques dans un service utilisant des antibiotiques de la réserve hospitalière, donc actifs mais très toxiques. PMID:22396670

  4. Suivi prospectif sur 5 ans des tentatives de suicide en population clinique dans la région de Fès, Maroc

    Science.gov (United States)

    Aarab, Chadya; Elghazouani, Fatima; Aalouane, Rachid; Rammouz, Ismail

    2014-01-01

    Au Maroc, les tentatives de suicide (TS) demeurent un sujet mal évalué à cause de considérations socioculturelles et l'absence d'approche longitudinale. L'objectif principal était d’évaluer le devenir des suicidants après 5ans au centre universitaire psychiatrique de Fès, les objectifs secondaires étaient l'estimation de la prévalence des TS, préciser les étiologies les plus fréquentes, et établir une corrélation entre les paramètres sociodémographiques, cliniques et évolutifs. Etude prospective à visée transversale et longitudinale, incluant les suicidants vus à l'hôpital psychiatrique de Fès, avec un suivi longitudinal sur 5ans. L’évaluation a été faite par un hétéro-questionnaire et le Mini International Neuropsychiatric Interview (MINI) cherchant le trouble psychiatrique sous jacent. On a recruté 105 patients suicidants, 62% des femmes, l’âge moyen est de 29,23ans. La prévalence des tentatives de suicide est de 3% sur l'ensemble des consultants à l’établissement. Les troubles de l'humeur, psychotiques et de personnalité ont occupé respectivement 37,6%, 27,7%, et 25,7% des cas. La récidive suicidaire a été notée chez 54% des patients, était significativement corrélée à la vie solitaire (P: 0,039) et à la présence d'antécédents familiaux de TS (P: 0,046). L'utilisation de moyens violents était significativement fréquente chez les patients psychotiques. Après 5ans, 32 patients ont répondu à notre appel. Le taux de récidive était de 15%. On a noté trois cas de décès dont deux suicides confirmés. Les résultats confirment les données de la littérature scientifique avec certaines particularités cliniques et évolutives. PMID:25478042

  5. Séroprévalence de Mycoplasma gallisepticum et de Mycoplasma synoviae dans les élevages reproducteurs type poulet de chair au Maroc de 1983 au 2005

    Directory of Open Access Journals (Sweden)

    Saadia NASSIK

    2014-03-01

    Full Text Available Les mycoplasmoses aviaires, particulièrement Mycoplasma gallisepticum (MG et Mycoplasma synoviae (MS sont des infections insidieuses respiratoires, génitales ou articulaires, entraînant de lourdes pertes économiques dans les différents types d’élevage avicole.L’objectif de cette étude est de tracer l’évolution des infections mycoplasmiques aviaires dues à MG et MS à partir d’une synthèse des enquêtes sérologiques réalisées au Maroc et d’évaluer les retombées de la nouvelle loi sanitaire. Ces enquêtes ont concerné 12, 13 et 15 élevages de poules reproductrices situés dans différentes régions, notamment les principaux axes de productions avicoles réalisées respectivement en 1983, 2002 et 2005. Les sérums recueillis ont été testés par Agglutination Rapide sur Lame (ARL afin d’identifier les élevages positifs. Les résultats sérologiques ont révélé la présence des anticorps contre MG et MS avec des taux d’infection variables en fonction de l’année d’étude et du germe. En effet, Les prévalences obtenues sont très importantes surtout pour MS qui dépassent les 50% ; un pic a été noté en 2002 (MG:30,76% et (MS:76,92%, avec une légère régression en 2005 (MG:26,67% et (MS:66,67 %.Ces taux d’infections non négligeables incitent à l’amélioration des normes d’hygiène et de biosécurité avec un accompagnement vétérinaire rigoureux conformément aux directives de la loi.

  6. La tectonique panafricaine du secteur d’Igherm : implication des dômes extensifs tardi a post-orogeniques (Anti-Atlas Occidental, Maroc

    Directory of Open Access Journals (Sweden)

    Soulaimani, A.

    2005-12-01

    Full Text Available L’évolution tectonique tardi-orogénique panafricaine du secteur d’Igherm (Anti-Atlas occidental, Maroc se caractérise par l’exhumation des parties profondes paléoprotérozoïques à l’image des dômes extensifs. Elle est contrôlée par un détachement principal ductile de faible pendage et des détachements de fort pendage de type extensionnel qui succèdent à un raccourcissement régional de direction NW-SE. Le détachement principal subhorizontal, est souligné par des mylonites de faible degré métamorphique. Il sépare deux unités : l’unité inférieure (complexe métamorphique du Paléoprotérozoïque à comportement ductile et l’unité supérieure (Quartzites néoprotérozoïques du Supergroupe de l’Anti-Atlas à comportement fragile. Cette évolution coïncide avec la mise en place des bassins « supradétachement » du Supergroupe de Ouarzazate durant l’extension qui aurait débuté après le raccourcissement panafricain datés vers 650 Ma. L’évènement extensionnel peut être généralisé à tout l’Anti-Atlas occidental.La evolución tectónica tardi-orogénica panafricana del sector de Igherm (Anti-Atlas occidental, Marruecos se caracteriza por la exhumación de las partes profundas proterozoicas como domos extensivos. Está controlada por un despegue principal dúctil con poco buzamiento y despegues con alto buzamiento de tipo extensional que se sobreponen a un acortamiento regional de dirección NO-SE. El despegue principal subhorizontal viene marcado por milonitas con metamorfismo de grado bajo. Este accidente separa dos unidades : la unidad inferior (complejo metamórfico del Paleoproterozoico de comportamiento dúctil y la unidad superior (cuarcitas del neoproterozoico del Supergrupo del Anti-Atlas de comportamiento frágil. Esta evolución coincide con el origen de las cuencas de «supra-detachment» del Supergrupo de Ouarzazate durante la extensión que se habría producido después del acortamiento

  7. Profil épidémiologique des pathologies respiratoires chez l’enfant à l’Hôpital d’Enfants de Rabat, Maroc

    Science.gov (United States)

    Benchekroun, Ilham; Boubkraoui, Mohamed El Mahdi; Mekaoui, Nour; Karboubi, Lamia; Mahraoui, Chafiq; Dakhama, Badr Sououd Benjelloun

    2017-01-01

    Introduction Les pathologies respiratoires représentent un motif fréquent d'hospitalisation en pédiatrie. L'objectif de cette étude était d'évaluer le profil épidémiologique des pathologies respiratoires chez l'enfant à l'hôpital d'enfants de Rabat, Maroc. Méthodes Il s'agit d'une étude observationnelle transversale qui a concerné tous les cas d'enfants âgés de 3 mois à 15 ans hospitalisés pour une pathologie respiratoire au service de pneumoallergologie et infectiologie pédiatriques de l'hôpital d'enfants de Rabat sur une période d'une année, du 1 janvier 2014 au 31 décembre 2014. Résultats Sur 3537 patients hospitalisés, 2493 (70,5%) l'ont été pour une pathologie respiratoire. Les hospitalisations pour exacerbation d'asthme (p < 0,001), bronchiolite aigüe (p < 0,001) et dyspnée laryngée (p = 0,004) étaient plus fréquentes chez le garçon alors que les hospitalisations pour pneumopathie aigüe (p = 0,005), pour inhalation de corps étranger (p = 0,007) et pour coqueluche (p = 0,020) étaient plus fréquentes chez la fille. Les hospitalisations pour pneumopathie aigüe (p < 0,001), exacerbation de séquelles graves de virose (p < 0,001) et pour coqueluche (p < 0,001) étaient plus fréquentes chez le nourrisson. Les hospitalisations pour pneumopathie aigüe (p < 0,001) et pour coqueluche (p = 0,015) étaient plus fréquentes en période automnohivernale. Conclusion Les motifs d'hospitalisation étaient dominés par les exacerbations d'asthme et la bronchiolite aigüe, lesquelles étaient plus fréquentes chez le garçon. Les infections respiratoires, représentées par les pneumopathies aigües et la coqueluche, étaient plus fréquentes en période automnohivernale et touchaient plus le nourrisson. PMID:29675122

  8. Les leishmanioses cutanées à Leishmania major et à Leishmania tropica au Maroc: aspects épidémio-cliniques comparatifs de 268 cas

    Science.gov (United States)

    Chiheb, Soumia; Slaoui, Widad; Mouttaqui, Tarik; Riyad, Meriem; Benchikhi, Hakima

    2014-01-01

    Introduction Depuis 1995, le Maroc a connu une réactivation des foyers de leishmanioses cutanées (LC) à L. major et une nouvelle répartition géographique des foyers à L. tropica. Le but de cette étude est de comparer les aspects épidémio-cliniques associés aux LC potentiellement dûes à L. major et à L. tropica. Méthodes Une étude rétrospective a colligé 268 cas de LC au service de dermatologie du CHU Ibn Rochd de Casablanca entre Janvier 1995 et Septembre 2010. Les données étaient analysées par Epi info version 3.5.1. Le test X2 était appliqué (Différence significative = p< 0,05). Résultats Deux cent soixante-huit cas de LC ont été colligés, dont 160 femmes et 108 hommes. Ils ont été répartis en 123 patients originaires des foyers à L.major et 145 patients originaires des foyers à L. tropica. L'aspect ulcéronodulaire, ulcérovégétant ou végétant était retrouvé dans 58 cas (47,2%) des cas de LC à L. major versus 24 cas (16,7%) dans la L.C à L. tropica. L'aspect papulonodulaire était retrouvé dans 84 cas (58%) de LC à L. tropica contre 41 cas (33,3%) de LC à L. major. Conclusion Dans la LC à L. major, l'atteinte des membres et les aspects cliniques végétant ou ulcéro-végétant restent toujours prédominants. Dans la L.C à L. tropica, l'atteinte papulonodulaire unique du visage reste prédominante mais des formes ulcéronodulaires, végétantes ou ulcérovégétantes existent également dans les foyers récents à L. tropica, prêtant à confusion cliniquement avec des LC à L. major. PMID:25810796

  9. Le retour des jeunes diplômés en zone rurale au Maroc: Quelles interactions entre trajectoires individuelles et projets collectifs ?

    Directory of Open Access Journals (Sweden)

    Nabila Aroussi Bachari

    2015-06-01

    Full Text Available l y a, dans les zones rurales du Maroc, une présence de plus en plus affirmée de jeunes diplômés. Ces jeunes peuvent jouer un rôle important pour le développement de ces zones rurales, mais à condition de se construire un rôle économique et social, qui leur permette de fonder un projet de vie en zone rurale. L’étude porte sur 11 jeunes diplômés qui ont initié des projets collectifs en zone rurale dans la province de Séfrou, grâce à des financements publics. Nous étudions les interactions entre les trajectoires individuelles de ces jeunes diplômés et leur projet collectif. Ces jeunes ont étudié voire travaillé pendant un temps en ville avant d’initier un projet collectif en zone rurale, à la fois du fait des difficultés d’insertion en ville mais aussi pour contribuer au développement de leur douar d’origine. Les projets de ces jeunes peuvent être d’ordre purement économique (coopérative de séchage de prune par exemple ou bien d’animation rurale. Plusieurs des jeunes enquêtés sont actifs à la fois dans la sphère économique et dans l’animation rurale, et jugent ces deux acticités comme complémentaires et non en opposition. Ces projets collectifs offrent à leur tour des opportunités de « projets de vie » en zone rurale pour ces jeunes. Si la capacité de ces projets de générer un revenu stable est un critère fort pour que ces jeunes se construisent un tel projet de vie en zone rurale, le rôle d’animateur de développement rural est aussi un élément important. Ces différents projets ont obtenu des financements publics de différents types qui ont, dans deux des quatre cas étudiés, explicitement pris en compte la présence de jeunes diplômés dans les projets. Cependant, ces financements ont souvent été accordés dans le cadre de démarches ponctuelles, qui pourraient être menées de façon plus institutionnalisée.

  10. Particulate versus non-particulate corticosteroids for transforaminal nerve root blocks. Comparison of outcomes in 494 patients with lumbar radiculopathy

    Energy Technology Data Exchange (ETDEWEB)

    Bensler, Susanne; Sutter, Reto; Pfirrmann, Christian W.A.; Peterson, Cynthia K. [Orthopaedic University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); University of Zurich, Faculty of Medicine, Zurich (Switzerland)

    2018-03-15

    We set out to compare outcomes in CT-guided lumbar transforaminal nerve root block patients receiving either particulate or non-particulate corticosteroids. This was a retrospective comparative effectiveness outcomes study on two cohorts of lumbar radiculopathy patients. 321 received particulate and 173 non-particulate corticosteroids at CT-guided transforaminal lumbar nerve root injections. The particulate steroid was used from October 2009 until May 2014 and the non-particulate steroid was used from May 2014. Pain levels were collected at baseline using an 11-point numerical rating scale (NRS) and at 1 day, 1 week and 1 month. Overall 'improvement' was assessed using the Patients' Global Impression of Change (PGIC) at these same time points (primary outcome). The proportions of patients 'improved' were compared between the two groups using the Chi-square test. The NRS change scores were compared using the unpaired t-test. A significantly higher proportion of patients treated with particulate steroids were improved at 1 week (43.2 % vs. 27.7 %, p = 0.001) and at 1 month (44.3 % vs. 33.1 %, p = 0.019). Patients receiving particulate steroids also had significantly higher NRS change scores at 1 week (p = 0.02) and 1 month (p = 0.007). Particulate corticosteroids have significantly better outcomes than non-particulate corticosteroids. (orig.)

  11. Le commerce transnational « informel », vecteur d’une nouvelle hiérarchie de lieux. L’exemple de la périphérie urbaine de Salé (Maroc)

    OpenAIRE

    Bennafla, Karine

    2016-01-01

    Cet article examine les implications spatiales du commerce transnational dans les pays intermédiaires tel le Maroc. Si l’accentuation des réformes néo-libérales entraîne l’ouverture de grandes surfaces, de magasins franchisés ou de malls, elle ne signe pas la fin du commerce « informel », tout aussi globalisé. La nouvelle hiérarchisation de lieux sous l’effet du commerce transnational est peu abordée dans la littérature sur le commerce informel marocain. L’exemple d’une centralité marchande i...

  12. Estimates of Particulate Mass in Multi-Canister Overpacks

    International Nuclear Information System (INIS)

    SLOUGHTER, J.P.

    2000-01-01

    High, best estimate, and low values are developed for particulate inventories within MCO baskets that have been loaded with freshly cleaned fuel assemblies and scrap. These per-basket estimates are then applied to all anticipated MCO payload configurations to identify which configurations are bounding for each type of particulate. Finally the resulting bounding and nominal values for residual particulates are combined with corresponding values [from other documents] for particulates that may be generated by corrosion of exposed uranium after the fuel has been cleaned. The resulting rounded nominal estimate for a typical MCO after 40 years of storage is 8 kg. The estimate for a bounding total particulate case MCO is that it may contain up to 64 kg of particulate after 40 years of storage

  13. Estimates of particulate mass in multi-canister overpacks

    International Nuclear Information System (INIS)

    SLOUGHTER, J.P.

    1999-01-01

    High, best estimate, and low values are developed for particulate inventories within MCO baskets that have been loaded with freshly cleaned fuel assemblies and scrap. These per-basket estimates are then applied to all anticipated MCO payload configurations to identify which configurations are bounding for each type of particulate. Finally the resulting bounding and nominal values for residual particulates are combined with corresponding values [from other documents] for particulate that may be generated by corrosion of exposed uranium after the fuel has been cleaned. The resulting rounded nominal estimate for a typical MCO after 40 years of storage is 8 kg. The estimate for a bounding total particulate case MCO is that it may contain up to 64 kg of particulate after 40 years of storage

  14. Estimates of particulate mass in multi-canister overpacks

    Energy Technology Data Exchange (ETDEWEB)

    SLOUGHTER, J.P.

    1999-02-25

    High, best estimate, and low values are developed for particulate inventories within MCO baskets that have been loaded with freshly cleaned fuel assemblies and scrap. These per-basket estimates are then applied to all anticipated MCO payload configurations to identify which configurations are bounding for each type of particulate. Finally the resulting bounding and nominal values for residual particulates are combined with corresponding values [from other documents] for particulate that may be generated by corrosion of exposed uranium after the fuel has been cleaned. The resulting rounded nominal estimate for a typical MCO after 40 years of storage is 8 kg. The estimate for a bounding total particulate case MCO is that it may contain up to 64 kg of particulate after 40 years of storage.

  15. Analysis of atmospheric particulate samples via instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Greenberg, R.R.

    1990-01-01

    Instrumental neutron activation analysis (INAA) is a powerful analytical technique for the elemental characterization of atmospheric particulate samples. It is a true multielement technique with adequate sensitivity to determine 30 to 40 elements in a sample of atmospheric particulate material. Its nondestructive nature allows sample reanalysis by the same or a different analytical technique. In this paper as an example of the applicability of INAA to the study of atmospheric particulate material, a study of the emissions from municipal incinerators is described

  16. Shielded regeneration heating element for a particulate filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2011-01-04

    An exhaust system includes a particulate filter (PF) that is disposed downstream from an engine. The PF filters particulates within an exhaust from the engine. A heating element heats particulate matter in the PF. A catalyst substrate or a flow converter is disposed upstream from said heating element. The catalyst substrate oxidizes the exhaust prior to reception by the heating element. The flow converter converts turbulent exhaust flow to laminar exhaust flow prior to reception by the heating element.

  17. Sexuation, valorisation et particularisation des « femmes chefs d’entreprise » dans la région d’Agadir (Maroc

    Directory of Open Access Journals (Sweden)

    Hélène Martin

    2012-05-01

    Full Text Available Cet article s’intéresse à l’émergence de la catégorie d’entrepreneure et à sa légitimation sociale dans la région d’Agadir (Maroc à partir d’une recherche de terrain qui eut lieu entre 2003 et 2006. Il rend d’abord compte des conditions historiques d’émergence de l’entreprenariat féminin, en revenant en particulier sur la division sexuée du travail propre au type de capitalisme imposé par le colonialisme, sur les conséquences matérielles et idéologiques de la politique néolibérale dans laquelle s’est engagé le Maroc dès les années 1980 et sur la révision de la Moudawana en 2004. Ensuite, l’auteure montre que la légitimation de l’entreprenariat féminin passe par un processus de sexuation de ce dernier. Cette sexuation s’inscrit dans un registre moral qui mobilise des « valeurs traditionnelles » associées à la féminité et qui occasionne la construction de figures relativement consensuelles de femmes (plutôt valorisées et d’hommes (plutôt minorisés sur un mode antagoniste et propre au contexte. Cependant, les conditions socio-économiques dans lesquelles se trouvent ces entrepreneures et leurs familles, à savoir l’imbrication des rapports de sexe et de classe, engagent ces dernières et leurs conjoints dans des rapports plus ou moins transgressifs aux « valeurs traditionnelles » prônées.Women entrepreneurs in the Agadir region of Morocco: sexuation, specificities and positive value attributed to a new social categoryThis article focuses on the emergence of a new category of women entrepreneurs and the issue of its social legitimacy in the region of Agadir (Morocco on the basis of a field study carried out between 2003 and 2006. It presents the historical conditions of the emergence of enterpreneurial roles taken on by women, revisiting in particular the gendered division of labor characteristic of the type of capitalism imposed by colonial powers, the material and ideological

  18. Particulate matter and neutron activation analysis

    International Nuclear Information System (INIS)

    Otoshi, Tsunehiko

    2003-01-01

    In these years, economy of East Asian region is rapidly growing, and countries in this region are facing serious environmental problems. Neutron activation analysis is known as one of high-sensitive analytical method for multi elements. And it is a useful tool for environmental research, particularly for the study on atmospheric particulate matter that consists of various constituents. Elemental concentration represents status of air, such as emission of heavy metals from industries and municipal incinerators, transportation of soil derived elements more than thousands of kilometers, and so on. These monitoring data obtained by neutron activation analysis can be a cue to evaluate environment problems. Japanese government launched National Air Surveillance Network (NASN) employing neutron activation analysis in 1974, and the data has been accumulated at about twenty sampling sites. As a result of mitigation measure of air pollution sources, concentrations of elements that have anthropogenic sources decreased particularly at the beginning of the monitoring period. However, even now, concentrations of these anthropogenic elements reflect the characteristics of each sampling site, e.g. industrial/urban, rural, and remote. Soil derived elements have a seasonal variation because of the contribution of continental dust transported by strong westerly winds prevailing in winter and spring season. The health effects associated with trace elements in particulate matter have not been well characterized. However, there is increasing evidence that particulate air pollution, especially fine portion of particles in many different cities is associated with acute mortality. Neutron activation analysis is also expected to provide useful information to this new study field related to human exposures and health risk. (author)

  19. Activation analysis of air particulate matter

    International Nuclear Information System (INIS)

    Alian, A.; Sansoni, B.

    1988-11-01

    This review on activation analysis of air particulate matter is an extended and updated version of a review given by the same authors in 1985. The main part is aimed at the analytical scheme and refers to rules and techniques for sampling, sample and standard preparation, irradiation and counting procedures, as well as data processing, - evaluation, and - presentation. Additional chapters deal with relative and monostandard methods, the use of activation analysis for atmosphere samples in various localities, and level of toxic and other elements in the atmosphere. The review contains 190 references. (RB)

  20. Neutron Imaging of Diesel Particulate Filters

    International Nuclear Information System (INIS)

    Strzelec, Andrea; Bilheux, Hassina Z.; Finney, Charles E.A.; Daw, C. Stuart; Foster, Dave; Rutland, Christopher J.; Schillinger, Burkhard; Schulz, Michael

    2009-01-01

    This article presents nondestructive neutron computed tomography (nCT) measurements of Diesel Particulate Filters (DPFs) as a method to measure ash and soot loading in the filters. Uncatalyzed and unwashcoated 200cpsi cordierite DPFs exposed to 100% biodiesel (B100) exhaust and conventional ultra low sulfur 2007 certification diesel (ULSD) exhaust at one speed-load point (1500rpm, 2.6bar BMEP) are compared to a brand new (never exposed) filter. Precise structural information about the substrate as well as an attempt to quantify soot and ash loading in the channel of the DPF illustrates the potential strength of the neutron imaging technique

  1. Particulate characterization by PIXE multivariate spectral analysis

    International Nuclear Information System (INIS)

    Antolak, Arlyn J.; Morse, Daniel H.; Grant, Patrick G.; Kotula, Paul G.; Doyle, Barney L.; Richardson, Charles B.

    2007-01-01

    Obtaining particulate compositional maps from scanned PIXE (proton-induced X-ray emission) measurements is extremely difficult due to the complexity of analyzing spectroscopic data collected with low signal-to-noise at each scan point (pixel). Multivariate spectral analysis has the potential to analyze such data sets by reducing the PIXE data to a limited number of physically realizable and easily interpretable components (that include both spectral and image information). We have adapted the AXSIA (automated expert spectral image analysis) program, originally developed by Sandia National Laboratories to quantify electron-excited X-ray spectroscopy data, for this purpose. Samples consisting of particulates with known compositions and sizes were loaded onto Mylar and paper filter substrates and analyzed by scanned micro-PIXE. The data sets were processed by AXSIA and the associated principal component spectral data were quantified by converting the weighting images into concentration maps. The results indicate automated, nonbiased, multivariate statistical analysis is useful for converting very large amounts of data into a smaller, more manageable number of compositional components needed for locating individual particles-of-interest on large area collection media

  2. Vale nails down reduction of diesel particulate

    Energy Technology Data Exchange (ETDEWEB)

    Larmour, A.

    2010-09-01

    This article discussed innovations for reducing emissions of diesel particulate matter (DPM) from light-duty underground vehicles. DPM is a byproduct of diesel-powered equipment. Controlling these emissions at the source of generation is necessary for a healthy work environment and more cost effective than fresh air ventilation to reduce contaminant concentrations. Previous diesel particulate filter (DPF) systems required extensive human intervention, but this was deemed too inefficient. A DPF system that does not require human intervention was developed and proved successful in filter regeneration, longevity, and reliability. This DPF system uses a sintered metal filter element, a base metal, fuel-borne catalyst with an on-board dosing system, an electric heater that uses on-board power, and a sensor-based control unit. Software in the control unit adjusts fuel dosing rates and heater timing to ensure filter regeneration for different engines and operating scenarios. The new filter system is robust, and it has a compact design and long service-intervals. The product is still being tested to determine the costs and service life of the filter. More testing on fuel additives was deemed to be warranted, as was designing filter elements for larger engines used in heavy-duty vehicles.

  3. Ambient particulate matter as a risk factor for suicide.

    Science.gov (United States)

    Kim, Changsoo; Jung, Sang Hyuk; Kang, Dae Ryong; Kim, Hyeon Chang; Moon, Ki Tae; Hur, Nam Wook; Shin, Dong Chun; Suh, Il

    2010-09-01

    The authors assessed the relationship between exposure to ambient particulate matter and suicide in urban settings during a 1-year period. The association between particulate matter and suicide was determined using a time-stratified case-crossover approach in which subjects served as their own controls. All suicide cases (4,341) in 2004 that occurred in seven cities in the Republic of Korea were included. Hourly mean concentrations of particulate matter suicide risk associated with an interquartile range increase in particulate matter was determined by conditional logistic regression analysis after adjusting for national holidays and meteorological factors. Subgroup analysis was performed after stratification by underlying disease (cardiovascular disease, diabetes mellitus, chronic obstructive pulmonary disease, cancer, and psychiatric illness). The largest associations were a 9.0% increase (95% CI=2.4-16.1) and a 10.1% (95% CI=2.0-19.0) increase in suicide risk related to an interquartile range increase in particulate matter suicide) and particulate matter suicide), respectively. Among individuals with cardiovascular disease, a significant association between particulate matter suicide) and suicide was observed (18.9%; 95% CI=3.2-37.0). Conclusions: A transient increase in particulate matter was associated with increased suicide risk, especially for individuals with preexisting cardiovascular disease.

  4. 40 CFR 86.1343-88 - Calculations; particulate exhaust emissions.

    Science.gov (United States)

    2010-07-01

    ... determined from the following equation: er31au93.070 (1) Pmass = Mass of particulate emitted per test phase... (cubic meters) per revolution. This volume is dependent on the pressure differential across the positive... be applied before Vsf is determined. (4) Pf = Mass of particulate on the sample filter (or sample and...

  5. Process for off-gas particulate removal and apparatus therefor

    International Nuclear Information System (INIS)

    Carl, D.E.

    1997-01-01

    In the event of a breach in the off-gas line of a melter operation requiring closure of the line, a secondary vessel vent line is provided with a particulate collector utilizing atomization for removal of large particulates from the off-gas. The collector receives the gas containing particulates and directs a portion of the gas through outer and inner annular channels. The collector further receives a fluid, such as water, which is directed through the outer channel together with a second portion of the particulate-laden gas. The outer and inner channels have respective ring-like termination apertures concentrically disposed adjacent one another on the outer edge of the downstream side of the particulate collector. Each of the outer and inner channels curves outwardly away from the collector's centerline in proceeding toward the downstream side of the collector. Gas flow in the outer channel maintains the fluid on the channel's wall in the form of a ''wavy film,'' while the gas stream from the inner channel shears the fluid film as it exits the outer channel in reducing the fluid to small droplets. Droplets formed by the collector capture particulates in the gas stream by one of three mechanisms: impaction, interception or Brownian diffusion in removing the particulates. The particulate-laden droplets are removed from the fluid stream by a vessel vent condenser or mist eliminator. 4 figs

  6. Method for immobilizing particulate materials in a packed bed

    Science.gov (United States)

    Even, Jr., William R.; Guthrie, Stephen E.; Raber, Thomas N.; Wally, Karl; Whinnery, LeRoy L.; Zifer, Thomas

    1999-01-01

    The present invention pertains generally to immobilizing particulate matter contained in a "packed" bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that a) the particulate retains its essential chemical nature, b) the local movement of the particulate particles is not unduly restricted, c) bulk powder migration and is prevented, d) physical and chemical access to the particulate is unchanged over time, and e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport.

  7. The investigation of atmospheric particulate matter pollution in Suzhou

    International Nuclear Information System (INIS)

    Chen Yi'ou; Zhang Yuliang; Wang Ya; Wang Pei; Tian Hailin

    2012-01-01

    Objective: To investigate the pollution status, vertical distribution and concentration variation within 24 hours of total suspended particles (TSPs), particulate matter ≤10 μm (PM10), particulate matter ≤5 (PM5) and particulate matter ≤2.5 μm (PM2.5) in major functional areas of Suzhou and the protective effect of different type masks on particulate matter. Methods: (1) The concentration of atmospheric TSPs, PM10, PM5 and PM2.5 in seven functional areas in Suzhou was monitored for three consecutive days. (2) A residential building of 25 stories was chosen and the concentration of TSPs, PM10, PM5, PM2.5 was detected at the 1st, 5th, 10th, 15th, 20 th and the 25th floor respectively. (3) The concentrations of the four particulate matter were detected every two-hours for three consecutive days to investigate how concentration of particulate matter varies within 24 hours. (4) The concentration of the four kinds of particulate matter was analyzed with the sampling head of monitor wrapped with disposable non-woven medical mask, fashion-type mask, gauze mask or activated carbon anti-dust mask respectively, and the protective effect of the four masks on particulate matter was compared. Results: (1) The concentration of PM2.5 was higher than the national health limit in all seven functional areas in Suzhou. (2) No significant difference in vertical distribution of particulate matter was found among different floors in residential buildings (P>0.05). (3) Two small peaks of particulate matter appeared in the morning and evening respectively while the top appeared at dawn (P< 0.05). (4) Disposable non-woven medical mask showed the best protective effect on particulate matter among the four tested masks. Conclusion: PM2.5 is the main particulate matter in Suzhou area. In addition the 4 kinds of particulate matter: TSP, PM10, PM5 and PM2.5 are of higher concentration in the early morning. No significant difference was detected from an altitude of less than 75 meters

  8. Epidémiologie et facteurs de risque des complications respiratoires majeures après chirurgie de l'aorte abdominale au CHU Ibn Sina, Maroc

    Science.gov (United States)

    Awab, Almahdi; Elahmadi, Brahim; Lamkinsi, Tarik; El Moussaoui, Rachid; El Hijri, Ahmed; Azzouzi, Abderrahim; Alilou, Mustapha

    2013-01-01

    Introduction L'incidence des complications respiratoires postopératoires (CRPO) reste très diversement appréciées selon les critères diagnostiques retenues dans les différentes études, ce qui la fait varier de 5 à plus de 50%. Les CRPO majeurs après chirurgie de l'aorte abdominale sont responsables d'une grande morbi-mortalité pouvant aller jusqu’à 36%, d'une durée d'hospitalisation et d'un coût plus importants. Ainsi dans l'optique d'améliorer notre prise en charge périopératoire de la chirurgie de l'aorte, nous avons décidé de mener une étude pour dresser le profil épidémiologique et déterminer les facteurs de risque des complications respiratoires dans notre contexte Méthodes Il s'agit d'une étude de cohorte rétrospective du mois de Janvier 2007 au mois de décembre 2011 portant sur l'ensemble des patients opérés pour pathologie aortique au bloc opératoire central de l'hôpital Ibn Sina de Rabat, Maroc. Résultats Cent vingt cinq patients ont été inclus dans notre étude, 24 patients ont été opérés pour anévrysme de l'aorte abdominale et 101 patients pour lésion occlusive aortoiliaque. Dans notre série 22 malades soit 17,6% ont présenté une complication respiratoire majeure avec, une reventilation dans 4,8% des cas, une difficulté de sevrage de la ventilation artificielle dans 3,2% des cas, une pneumopathie dans 4% des cas, un syndrome de détresse respiratoire aigue (SDRA) dans 4% des cas et une nécessité de fibroaspiration bronchique dans 1,6% des cas. En analyse univariée: l’âge, la présence d'une BPCO avec dyspnée stade 3 ou 4, la présence d'une anomalie à l'EFR préopératoire, la présence d'un stade avancé (III ou IV) de LOAI et la reprise chirurgicale étaient statistiquement associés à la survenue d'une complication respiratoire postopératoire. En analyse multivariée, seule une anomalie à l'EFR en préopératoire constituait un facteur de risque indépendant de survenue d'une complication

  9. Hémophilie: état des lieux dans un service de pédiatrie dans la région de l'oriental du Maroc

    Science.gov (United States)

    Benajiba, Noufissa; Boussaadni, Yousra EL; Aljabri, Mohammed; Bentata, Yassamine; Amrani, Rim; Rkain, Maria

    2014-01-01

    Pour les pays en voie de développement, l'hémophilie continue d’être une maladie de conséquence médicale et sociale désastreuse. Le but de ce travail est d'analyser le suivi d'une cohorte de patients hémophiles. Patients et méthodes: étude prospective étalée sur deux années et menée au centre référent d'hémophilie dans la région de l'orient du Maroc. Ont été inclus tous les patients présentant une hémophilie confirmée et âgé de moins de 18 ans. Résultats: sur 16 hémophiles, Quinze patients présentait une hémophilie A, l’âge moyen des patients était de 6,18 ans, la forme sévère, représentait 20,7%, la forme modérée: 33,3% et la forme mineure: 40%. Les circonstances de découverte étaient post circoncisionnelle chez 53,3% des patients, 20,7% post traumatique, 20% à l’âge de la marche; la durée d’évolution variait entre 2 mois et 10 ans. L'hémarthrose a été décrite au niveau des genoux, coudes et chevilles, avec une moyenne allant de 2 à 5 fois par an; l'arthropathie a été remarquée dans 33,3%. Le bilan immunologique a révélé des facteurs circulant inhibant chez deux patients. Le traitement était à base d'antalgiques, de plasma frais congelé. L'administration de facteurs VIII recombinés a été instaurée chez 40,6% des patients (plus de 90% des formes modérées et graves), grâce au programme national de prise en charge des hémophiles. Le décès était noté dans un seul cas lié à une hémorragie cérébrale. Conclusion: Nous insistons sur l'intérêt du programme national de prise en charge des hémophiles dernièrement instauré qui pourrait améliorer les conditions de vie de ces enfants. PMID:25404986

  10. Trace elemental analysis of the aerosol particulates in northern Punjab

    International Nuclear Information System (INIS)

    Iqbal, M.Z.

    2002-01-01

    Trace elemental analysis of the aerosol particulates was studied in the atmosphere of Lahore, Faisalabad, Islamabad, Sheikhupura, Wah Cantt. And Khanispur. The amount of the aerosol particulates in the above mentioned areas was compared to the U.S. EPA maximum permissible limits. Scavenging mechanism of the aerosol particulates through precipitation was studied in the atmosphere of Lahore and Sheikhupura by using HPLC and ICP-AES techniques. The site distribution and morphological structure of the aerosol particulates was studied by using Scanning Electron Microscope model JSM-35CF. Trace elemental composition of the aerosol particulates in the atmosphere of the selected areas of Pakistan was carried out by using NAA. The elements thus studied were Ce, Yb, Se, Cr, Hf, Cs, Sc, Fe, Co, Eu, Sb, Mo, Ba, Zn, Hg, Br, Na, Gd, Sm, Nd and In while Pb and Cd were estimated by using ASS technique. (author)

  11. Particulate hot gas stream cleanup technical issues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    This is the tenth in a series of quarterly reports describing the activities performed under Contract No. DE-AC21-94MC31160. Analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance address aspects of filter operation that are apparently linked to the characteristics of the collected ash or the performance of the ceramic bed filter elements. Task I is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFS) and to relate these ash properties to the operation and performance of these filters. Task 2 concerns testing and failure analysis of ceramic filter elements. Under Task I during the past quarter, analyses were performed on a particulate sample from the Transport Reactor Demonstration Unit (TRDU) located at the University of North Dakota Energy and Environmental Research Center. Analyses are in progress on ash samples from the Advanced Particulate Filter (APF) at the Pressurized Fluidized-Bed Combustor (PFBC) that was in operation at Tidd and ash samples from the Pressurized Circulating Fluid Bed (PCFB) system located at Karhula, Finland. A site visit was made to the Power Systems Development Facility (PSDF) to collect ash samples from the filter vessel and to document the condition of the filter vessel with still photographs and videotape. Particulate samples obtained during this visit are currently being analyzed for entry into the Hot Gas Cleanup (HGCU) data base. Preparations are being made for a review meeting on ash bridging to be held at Department of Energy Federal Energy Technology Center - Morgantown (DOE/FETC-MGN) in the near future. Most work on Task 2 was on hold pending receipt of additional funds; however, creep testing of Schumacher FT20 continued. The creep tests on Schumacher FT20 specimens just recently ended and data analysis and comparisons to other data are ongoing. A summary and analysis of these creep results will be sent out shortly. Creep

  12. Exposure to particulate hexavalent chromium exacerbates allergic asthma pathology

    International Nuclear Information System (INIS)

    Schneider, Brent C.; Constant, Stephanie L.; Patierno, Steven R.; Jurjus, Rosalyn A.; Ceryak, Susan M.

    2012-01-01

    Airborne hexavalent chromate, Cr(VI), has been identified by the Environmental Protection Agency as a possible health threat in urban areas, due to the carcinogenic potential of some of its forms. Particulate chromates are produced in many different industrial settings, with high levels of aerosolized forms historically documented. Along with an increased risk of lung cancer, a high incidence of allergic asthma has been reported in workers exposed to certain inhaled particulate Cr(VI) compounds. However, a direct causal association between Cr(VI) and allergic asthma has not been established. We recently showed that inhaled particulate Cr(VI) induces an innate neutrophilic inflammatory response in BALB/c mice. In the current studies we investigated how the inflammation induced by inhaled particulate Cr(VI) might alter the pathology of an allergic asthmatic response. We used a well-established mouse model of allergic asthma. Groups of ovalbumin protein (OVA)-primed mice were challenged either with OVA alone, or with a combination of OVA and particulate zinc chromate, and various parameters associated with asthmatic responses were measured. Co-exposure to particulate Cr(VI) and OVA mediated a mixed form of asthma in which both eosinophils and neutrophils are present in airways, tissue pathology is markedly exacerbated, and airway hyperresponsiveness is significantly increased. Taken together these findings suggest that inhalation of particulate forms of Cr(VI) may augment the severity of ongoing allergic asthma, as well as alter its phenotype. Such findings may have implications for asthmatics in settings in which airborne particulate Cr(VI) compounds are present at high levels. -- Highlights: ► Allergic asthma correlated with exposure to certain inhaled particulate chromates. ► Direct causal association between Cr(VI) and allergic asthma not established. ► Cr exacerbated pathology and airway hyperresponsiveness in an OVA-challenged mouse. ► Particulate Cr

  13. Exposure to particulate hexavalent chromium exacerbates allergic asthma pathology

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Brent C. [Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC 20037 (United States); Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037 (United States); Constant, Stephanie L. [Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC 20037 (United States); Patierno, Steven R. [Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037 (United States); GW Cancer Institute, The George Washington University, Washington, DC 20037 (United States); Jurjus, Rosalyn A. [Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037 (United States); Ceryak, Susan M., E-mail: phmsmc@gwumc.edu [Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037 (United States)

    2012-02-15

    Airborne hexavalent chromate, Cr(VI), has been identified by the Environmental Protection Agency as a possible health threat in urban areas, due to the carcinogenic potential of some of its forms. Particulate chromates are produced in many different industrial settings, with high levels of aerosolized forms historically documented. Along with an increased risk of lung cancer, a high incidence of allergic asthma has been reported in workers exposed to certain inhaled particulate Cr(VI) compounds. However, a direct causal association between Cr(VI) and allergic asthma has not been established. We recently showed that inhaled particulate Cr(VI) induces an innate neutrophilic inflammatory response in BALB/c mice. In the current studies we investigated how the inflammation induced by inhaled particulate Cr(VI) might alter the pathology of an allergic asthmatic response. We used a well-established mouse model of allergic asthma. Groups of ovalbumin protein (OVA)-primed mice were challenged either with OVA alone, or with a combination of OVA and particulate zinc chromate, and various parameters associated with asthmatic responses were measured. Co-exposure to particulate Cr(VI) and OVA mediated a mixed form of asthma in which both eosinophils and neutrophils are present in airways, tissue pathology is markedly exacerbated, and airway hyperresponsiveness is significantly increased. Taken together these findings suggest that inhalation of particulate forms of Cr(VI) may augment the severity of ongoing allergic asthma, as well as alter its phenotype. Such findings may have implications for asthmatics in settings in which airborne particulate Cr(VI) compounds are present at high levels. -- Highlights: ► Allergic asthma correlated with exposure to certain inhaled particulate chromates. ► Direct causal association between Cr(VI) and allergic asthma not established. ► Cr exacerbated pathology and airway hyperresponsiveness in an OVA-challenged mouse. ► Particulate Cr

  14. Is there a difference in treatment outcomes between epidural injections with particulate versus non-particulate steroids?

    Energy Technology Data Exchange (ETDEWEB)

    Bensler, Susanne; Sutter, Reto; Pfirrmann, Christian W.A.; Peterson, Cynthia K. [Orthopedic University Hospital Balgrist, Department of Radiology, Zurich (Switzerland); University of Zurich, Faculty of Medicine, Zurich (Switzerland)

    2017-04-15

    To compare the outcomes of patients after interlaminar computed tomography (CT)-guided epidural injections of the lumbar spine with particulate vs. non-particulate steroids. 531 consecutive patients were treated with CT-guided lumbar interlaminar epidural injections with steroids and local anaesthetics. 411 patients received a particulate steroid and 120 patients received a non-particulate steroid. Pain levels were assessed using the 11-point numerical rating scale (NRS) and overall reported 'improvement' was assessed using the Patients Global Impression of Change (PGIC) at 1 day, 1 week and 1 month post-injection. Descriptive and inferential statistics were applied. Patients receiving particulate steroids had statistically significantly higher NRS change scores (p = 0.0001 at 1 week; p = 0.0001 at 1 month). A significantly higher proportion of patients receiving particulate steroids reported relevant improvement (PGIC) at both 1 week and 1 month post injection (p = 0.0001) and they were significantly less likely to report worsening at 1 week (p = 0.0001) and 1 month (p = 0.017). Patients treated with particulate steroids had significantly greater pain relief and were much more likely to report clinically relevant overall 'improvement' at 1 week and 1 month compared to the patients treated with non-particulate steroids. (orig.)

  15. Is there a difference in treatment outcomes between epidural injections with particulate versus non-particulate steroids?

    International Nuclear Information System (INIS)

    Bensler, Susanne; Sutter, Reto; Pfirrmann, Christian W.A.; Peterson, Cynthia K.

    2017-01-01

    To compare the outcomes of patients after interlaminar computed tomography (CT)-guided epidural injections of the lumbar spine with particulate vs. non-particulate steroids. 531 consecutive patients were treated with CT-guided lumbar interlaminar epidural injections with steroids and local anaesthetics. 411 patients received a particulate steroid and 120 patients received a non-particulate steroid. Pain levels were assessed using the 11-point numerical rating scale (NRS) and overall reported 'improvement' was assessed using the Patients Global Impression of Change (PGIC) at 1 day, 1 week and 1 month post-injection. Descriptive and inferential statistics were applied. Patients receiving particulate steroids had statistically significantly higher NRS change scores (p = 0.0001 at 1 week; p = 0.0001 at 1 month). A significantly higher proportion of patients receiving particulate steroids reported relevant improvement (PGIC) at both 1 week and 1 month post injection (p = 0.0001) and they were significantly less likely to report worsening at 1 week (p = 0.0001) and 1 month (p = 0.017). Patients treated with particulate steroids had significantly greater pain relief and were much more likely to report clinically relevant overall 'improvement' at 1 week and 1 month compared to the patients treated with non-particulate steroids. (orig.)

  16. Ultra fine particulates. Small particulates with large consequences?; Ultrafijn stof. Kleine deeltjes met grote gevolgen?

    Energy Technology Data Exchange (ETDEWEB)

    Hensema, A.; Keuken, M.; Kooter, I.; Verbeek, R.; Van Vugt, M. [TNO Science and Industry, Delft (Netherlands)

    2009-02-15

    The concentrations of ultra fine particles (and elementary carbon) have increased significantly near traffic routes. The amount of ultra fine particles (and the chemical composition of particulate matter) are related to traffic emissions and are therefore relevant to the established health effects. Better insight in the effectiveness of particulate matter policy requires more attention for ultra fine particles than just maintaining the standards for PM2,5 and PM10. [mk]. [Dutch] De concentraties van ultrafijne deeltjes (en elementair koolstof) zijn fors verhoogd in de buurt van verkeerswegen. Het aantal ultrafijne deeltjes (en de chemische samenstelling van fijnstof) gerelateerd aan verkeersemissies lijkt daarom relevant voor de vastgestelde gezondheidseffecten. Voor een beter inzicht in de effectiviteit van het fijnstofbeleid is meer aandacht nodig voor ultrafijne deeltjes dan alleen handhaving van de normen voor PM2,5 en PM10.

  17. Particulate emissions from residential wood combustion

    DEFF Research Database (Denmark)

    Luis Teles de Carvalho, Ricardo; Jensen, Ole Michael; Tarelho, Luis A. C.

    Residential wood combustion (RWC) in fireplaces and conventional appliances is the main contributor to fine particulate matter (PM2.5) emissions in Denmark and Portugal representing more than 30% of the total emissions [1;2]. Such estimations are uncertain concerning the wood consumption...... and official emission factors, not taking into account actual burning conditions in dwellings [3]. There is limited knowledge on the real-life performance and spatial distribution of existing appliance types. Few studies have been targeting to understand the influence of fuel operation habits on PM2...... the available estimations for Denmark and Portugal, suggesting a methodology to increase the accuracy of activity data and emission factors. This work is based on new studies carried out to quantify the PM2.5 emissions in daily life through field experiments in Danish dwellings and by considering typical...

  18. Particulates in Europe; Fijn stof in Europa

    Energy Technology Data Exchange (ETDEWEB)

    Eeftens, M.; Brunekreef, B. [Institute for Risk Assessment Sciences IRAS, Utrecht University, Utrecht (Netherlands)

    2013-08-15

    Although the same air quality standards apply across Europe, there are large differences in concentration within, but also between countries. There are also differences between the methods that these countries use for regular monitoring networks, which makes a direct comparison of concentrations difficult. The ESCAPE project (European Study of Cohorts for Air Pollution Effects) mapped the differences in the European particulate concentrations using one unified measuring method [Dutch] Hoewel voor heel Europa dezelfde luchtkwaliteitsnormen gelden, bestaan er grote concentratieverschillen binnen, maar ook tussen landen. Ook zijn er verschillen tussen de meetmethoden die deze landen binnen reguliere meetnetten hanteren, wat een directe vergelijking van concentraties vaak moeilijk maakt. Het ESCAPE-project (European Study of Cohorts for Air Pollution Effects) bracht de Europese fijnstofcontrasten in kaart met behulp van 1 identieke meetmethode.

  19. Recent observations of particulates in Nitinol

    International Nuclear Information System (INIS)

    Shabalovskaya, S.; Anderegg, J.; Humbeeck, J. van

    2008-01-01

    In spite of 40 years of history of Nitinol, the issues regarding its inclusions have been poorly explored. In our brief studies, conducted within the projects on surface design using Auger, energy-dispersive X-ray spectroscopy and scanning electrons microscopy, we discovered that particulates in NiTi medical alloys were always based on Ti: either ∼Ti 2 NiO oxide, titanium dioxide, titanium carbide or oxidized titanium carbide. Nonmetallic particles were rather brittle, had various shapes and sizes, and revealed different solubility in chemical solutions. The matrix material surrounding inclusions showed a tendency to localized corrosion. It was hypothesized that release of inclusion debris in the human body due to corrosion might compromise biocompatibility of Nitinol

  20. Method for identifying particulate fluoride compounds

    Energy Technology Data Exchange (ETDEWEB)

    Tufts, B J

    1960-01-01

    A method is described for identifying particulates containing fluorides and other complex fluorine compounds such as fluorosilicate in samples collected on membrane filters. The filter is treated with lead chloride to precipitate lead chlorofluoride at each fluoride-containing spot. This microspot is identified by examination in a light microscope. Sulfate and phosphate, which also precipitate if present, can be distinguished and do not interfere. Calibrations are given for the fluorides and the more insoluble salts, relating the original particle size to the reaction site size. Thus, the mass of the particles can be calculated. Results of some field tests in an area of fluoride pollution are given, and compared with standard testing procedures.

  1. Lability of Secondary Organic Particulate Matter

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Pengfei; Li, Yong Jie; Wang, Yan; Giles, Mary K.; Zaveri, Rahul A.; Bertram, Allan K.; Martin, Scot T.

    2016-10-24

    Accurate simulations of the consenctrations of atmospheric organic particulate matter (PM) are needed for predicting energy flow in the Earth’s climate system. In the past, simulations of organic PM widely assume equilibrium partitioning of semivolatile organic compounds (SVOCs) between the PM and surrounding vapor. Herein, we test this assumption by measuring evaporation rates and associated vapor mass concentration of organic films representative of atmospheric PM. For films representing anthropogenic PM, evaporation rates and vapor mass concentrations increased above a threshold relative humidity (RH), indicating equilibrium partitioning above a transition RH but not below. In contrast for films representing biogenic PM, no threshold was observed, indicating equilibrium partitioning at all RHs. The results suggest that the mass lability of atmospheric organic PM can differ in consequential ways among Earth’s natural biomes, polluted regions, and regions of land-use change, and these differences need to be considered when simulating atmospheric organic PM.

  2. Production, handling and characterization of particulate materials

    CERN Document Server

    Meesters, Gabriel

    2016-01-01

    This edited volume presents most techniques and methods that have been developed by material scientists, chemists, chemical engineers and physicists for the commercial production of particulate materials, ranging from the millimeter to the nanometer scale.  The scope includes the physical and chemical background, experimental optimization of equipment and procedures, as well as an outlook on future methods. The books addresses  issues of industrial importance such as specifications, control parameter(s), control strategy, process models, energy consumption and discusses the various techniques in relation to potential applications. In addition to the production processes, all major unit operations and characterization methods are described in this book. It differs from other books which are devoted to a single technique or a single material. Contributors to this book are acknowledged experts in their field. The aim of the book is to facilitate comparison of the different unit operations leading to optimum...

  3. Mass spectroscopic analysis of atmospheric particulate matter

    International Nuclear Information System (INIS)

    Wippel, R.

    1997-02-01

    Particulate matter (PM) in the atmosphere vary greatly in origin, in their physical and chemical properties and their effects on climate, atmospheric chemistry and health. Aerosol particles with an aerodynamic diameter less than two μm can enter the respiratory tract of humans when inhaled. Bulk analysis of ambient dust particles was performed using an inductively coupled plasma mass spectrometer (ICP-MS). The size-fractionated collected samples were analyzed after a leaching procedure that simulates the solution reactions occurring in the lungs. A disadvantage of bulk analysis is that it gives no information about the distribution of a certain element within the particles under investigation. A Laser-Microprobe-Mass-Analyzer (LAMMA-500) was used to obtain this information. At sampling sites in Austria and in Zimbabwe, Africa, single particles were sampled using a self-made impactor. One of the final aims in environmental analysis is to successfully apply receptor models that relate the chemical and physical properties of a receptor site to a source. The knowledge of the sources of atmospheric particulate matter is essential for environmental policy makers as well as for epidemiological studies. Artificial neural networks (ANN) have a remarkable ability to handle LAMMA-data. Three ANNs were used as a pattern recognition tool for LAMMA mass spectral data: a back-propagation net, a Kohonen network,and a counter-propagation net. Standard source profiles from the United States Environmental Protection Agency were used as training and test data of the different nets. The elemental patterns of the sum of 100 mass spectra of fine dust particles were presented to the trained nets and satisfactory recognition (> 80 %) was obtained. (author)

  4. Comparison of testing methods for particulate filters

    International Nuclear Information System (INIS)

    Ullmann, W.; Przyborowski, S.

    1983-01-01

    Four testing methods for particulate filters were compared by using the test rigs of the National Board of Nuclear Safety and Radiation Protection: 1) Measurement of filter penetration P as a function of particle size d by using a polydisperse NaC1 test aerosol and a scintillation particle counter; 2) Modified sodium flame test for measurement of total filter penetration P for various polydisperse NaC1 test aerosols; 3) Measurement of total filter penetration P for a polydisperse NaC1 test aerosol labelled with short-lived radon daughter products; 4) Measurement of total filter penetration P for a special paraffin oil test aerosol (oil fog test used in FRG according DIN 24 184, test aerosol A). The investigations were carried out on sheets of glass fibre paper (five grades of paper). Detailed information about the four testing methods and the used particle size distributions is given. The different results of the various methods are the base for the discussion of the most important parameters which influence the filter penetration P. The course of the function P=f(d) shows the great influence of the particle size. As expected there was also found a great dependence both from the test aerosol as well as from the principle and the measuring range of the aerosol-measuring device. The differences between the results of the various test methods are greater the lower the penetration. The use of NaCl test aerosol with various particle size distributions gives great differences for the respective penetration values. On the basis of these results and the values given by Dorman conclusions are made about the investigation of particulate filters both for the determination of filter penetration P as well as for the leak test of installed filters

  5. Particulate absorption properties in the Red Sea from hyperspectral particulate absorption spectra

    KAUST Repository

    Tiwari, Surya Prakash

    2018-03-16

    This paper aims to describe the variability of particulate absorption properties using a unique hyperspectral dataset collected in the Red Sea as part of the TARA Oceans expedition. The absorption contributions by phytoplankton (aph) and non-algal particles (aNAP) to the total particulate absorption coefficients are determined using a numerical decomposition method (NDM). The NDM is validated by comparing the NDM derived values of aph and aNAP with simulated values of aph and aNAP are found to be in excellent agreement for the selected wavelengths (i.e., 443, 490, 555, and 676nm) with high correlation coefficient (R2), low root mean square error (RMSE), mean relative error (MRE), and with a slope close to unity. Further analyses showed that the total particulate absorption coefficients (i.e., ap(443)average = 0.01995m−1) were dominated by phytoplankton absorption (i.e., aph(443)average = 0.01743m−1) with a smaller contribution by non-algal particles absorption (i.e., aNAP(443)average = 0.002524m−1). The chlorophyll a is computed using the absorption based Line Height Method (LHM). The derived chlorophyll-specific absorption ((a⁎ph = aph(λ)/ChlLH)) showed more variability in the blue part of spectrum as compared to the red part of spectrum representative of the package effect and changes in pigment composition. A new parametrization proposed also enabled the reconstruction of a⁎ph(λ) for the Red Sea. Comparison of derived spectral constants with the spectral constants of existing models showed that our study A(λ) values are consistent with the existing values, despite there is a divergence with the B(λ) values. This study provides valuable information derived from the particulate absorption properties and its spectral variability and this would help us to determine the relationship between the phytoplankton absorption coefficients and chlorophyll a and its host of variables for the Red Sea.

  6. Airborne soil particulates as vehicles for Salmonella contamination of tomatoes.

    Science.gov (United States)

    Kumar, Govindaraj Dev; Williams, Robert C; Al Qublan, Hamzeh M; Sriranganathan, Nammalwar; Boyer, Renee R; Eifert, Joseph D

    2017-02-21

    The presence of dust is ubiquitous in the produce growing environment and its deposition on edible crops could occur. The potential of wind-distributed soil particulate to serve as a vehicle for S. Newport transfer to tomato blossoms and consequently, to fruits, was explored. Blossoms were challenged with previously autoclaved soil containing S. Newport (9.39log CFU/g) by brushing and airborne transfer. One hundred percent of blossoms brushed with S. Newport-contaminated soil tested positive for presence of the pathogen one week after contact (PCompressed air was used to simulate wind currents and direct soil particulates towards blossoms. Airborne soil particulates resulted in contamination of 29% of the blossoms with S. Newport one week after contact. Biophotonic imaging of blossoms post-contact with bioluminescent S. Newport-contaminated airborne soil particulates revealed transfer of the pathogen on petal, stamen and pedicel structures. Both fruits and calyxes that developed from blossoms contaminated with airborne soil particulates were positive for presence of S. Newport in both fruit (66.6%) and calyx (77.7%). Presence of S. Newport in surface-sterilized fruit and calyx tissue tested indicated internalization of the pathogen. These results show that airborne soil particulates could serve as a vehicle for Salmonella. Hence, Salmonella contaminated dust and soil particulate dispersion could contribute to pathogen contamination of fruit, indicating an omnipresent yet relatively unexplored contamination route. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Particulate and soluble 210Pd activities in the deep sea

    International Nuclear Information System (INIS)

    Somayajulu, B.L.K.; Craig, H.

    1976-01-01

    Particulate and soluble, 210 Pb activities have been measured by filtration of large-volume water samples at two stations in the South Atlantic. Particulate phase 210 Pb (caught by a 0.4-μm filter) varies from 0.3% of total 210 Pb in equatorial surface water to 15% in the bottom water. The 'absolute activity' of 210 Pb per unit mass of particulate matter is about 10 7 times the activity of soluble 210 Pb per unit mass of water, but because the mass ratio of particulate matter to water is about 10 -8 , the particulate phase carries only about 10% of the total activity. In Antarctic surface water the particulate phase carries 40% of the total 210 Pb activity; the absolute activity of this material is about the same as in other water masses and the higher fraction is due to the much larger concentration of suspended matter in surface water in this region. In the equatorial Atlantic the particulate phase 210 Pb activity increases with depth, by a factor of 40 from surface to bottom, and by a factor of 4 from the Antarctic Intermediate water core to the Antarctic Bottom Water. (Auth.)

  8. A laser particulate spectrometer for a space simulation facility

    Science.gov (United States)

    Schmitt, R. J.; Boyd, B. A.; Linford, R. M. F.; Richmond, R. G.

    1975-01-01

    A laser particulate spectrometer (LPS) system was developed to measure the size and speed distributions of particulate contaminants. Detection of the particulates is achieved by means of light scattering and extinction effects using a single laser beam to cover a size range of 0.8 to 275 microns diameter and a speed range of 0.2 to 20 meters/second. The LPS system was designed to operate in the high-vacuum environment of a space simulation chamber with cold shroud temperatures ranging from 77 to 300 K.

  9. Particulate Emission Abatement for Krakow Boilerhouses

    International Nuclear Information System (INIS)

    Hucko, R.E.

    1997-01-01

    Environmental clean-up and pollution control are considered the foremost national priorities in Poland. The target of this cleanup is the Polish coal industry, which supplies the fuel to generate over 78% of Poland's primary energy production. This project addresses the problem of airborne dust and uncontrolled particulate emissions from boilerhouses, which represent a large fraction of the total in Poland. In Krakow alone, there are more than 2,000 uncontrolled boilers accounting for about half the total fuel use. The large number of low-capacity boilers poses both technical and economic challenges, since the cost of control equipment is a significant factor in the reduction of emissions. A new concept in dust collection, called a Core Separator, is proposed for this important application. The Core Separator is an advanced technology developed through research sponsored by the Department of Energy. It utilizes a highly efficient collector, which functions on the principle of inertial separation. The system is able to control fine particulate matter, as in the PMIO regulations, which limit the emission of dust particles below 10 microns in diameter. Its dust removal performance has been shown to be comparable to that of a medium-efficiency electrostatic precipitator (ESP). Yet, its cost is substantially lower than that of either an ESP or fabric filter. While the Core Separator achieves high efficiency, its power consumption is just slightly higher than that of a cyclone. It functions dry and without the aid of energy-consuming enhancements. It is simple, reliable, and unlike the ESP and fabric filter, easy to maintain. This combination of features make it ideal for the small boiler market in the City of Krakow. A highly qualified team has been assembled to execute this project. LSR Technologies, Inc., a technology-based company located in Acton, Massachusetts, is the developer of the Core Separator and holder of its patent rights. LSR has sold several of these

  10. Particulate Emission Abatement for Krakow Boilerhouses

    International Nuclear Information System (INIS)

    Hucko, R.E.

    1997-01-01

    Environmental clean-up and pollution control are considered the foremost national priorities in Poland. The target of this cleanup is the Polish coal industry, which supplies the fuel to generate over 78% of Poland's primary energy production. This project addresses the problem of airborne dust and uncontrolled particulate emissions from boilerhouses, which represent a large fraction of the total in Poland. In Krakow alone, there are more than 2,000 uncontrolled boilers accounting for about half the total fuel use. The large number of low-capacity boilers poses both technical and economic challenges, since the cost of control equipment is a significant factor in the reduction of emissions. A new concept in dust collection, called a Core Separator, is proposed for this important application. The Core Separator is an advanced technology developed through research sponsored by the Department of Energy. It utilizes a highly efficient collector, which functions on the principle of inertial separation. The system is able to control fine particulate matter, as in the PMIO regulations, which limit the emission of dust particles below 10 microns in diameter. Its dust removal performance has been shown to be comparable to that of a medium-efficiency electrostatic precipitator (ESP). Yet, its cost is substantially lower than that of either an ESP or fabric filter. While the Core Separator achieves high efficiency, its power consumption is just slightly higher than that of a cyclone. It functions dry and without the aid of energy-consuming enhancements. It is simple, reliable, and unlike the ESP and fabric filter, easy to maintain. This combination of features make it ideal for the small boiler market in the City of Krakow. A highly qualified team has been assembled to execute this project. LSR Technologies, Inc., a technology-based company located in Acton, Massachusetts, is the developer of the Core Separator and holder of its patent rights. LSR has sold several of these

  11. Particulate hot gas stream cleanup technical issues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    This is the eleventh in a series of quarterly reports describing the activities performed under Contract No. DE-AC21-94MC31160. Analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance address aspects of filter operation that are apparently linked to the characteristics of the collected ash or the performance of the ceramic bed filter elements. Task 1 is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFS) and to relate these ash properties to the operation and performance of these filters. Task 2 concerns testing and failure analysis of ceramic filter elements. Under Task 1 during the past quarter, analyses were completed on samples obtained during a site visit to the Power Systems Development Facility (PSDF). Analyses are in progress on ash samples from the Advanced Particulate Filter (APF) at the Pressurized Fluidized-Bed Combustor (PFBC) that was in operation at Tidd and ash samples from the Pressurized Circulating Fluid Bed (PCFB) system located at Karhula, Finland. An additional analysis was performed on a particulate sample from the Transport Reactor Demonstration Unit (TRDU) located at the University of North Dakota Energy and Environmental Research Center. A manuscript and poster were prepared for presentation at the Advanced Coal-Based Power and Environmental Systems `97 Conference scheduled for July 22 - 24, 1997. A summary of recent project work covering the mechanisms responsible for ash deposit consolidation and ash bridging in APF`s collecting PFB ash was prepared and presented at FETC-MGN in early July. The material presented at that meeting is included in the manuscript prepared for the Contractor`s Conference and also in this report. Task 2 work during the past quarter included mechanical testing and microstructural examination of Schumacher FT20 and Pall 326 as- manufactured, after 540 hr in service at Karhula, and after 1166 hr in service at

  12. Air pollution in Aleppo city, gases,suspended particulates

    International Nuclear Information System (INIS)

    Othman, I.; Sabra, Sh.; Al-Kharfan, K.

    1994-06-01

    Total suspended particulates measured by using High Volume Air Sampler. The Co and O 3 were measured during weekday and weekend. The concentration of all pollutants at city center are higher than other measured areas. (author). 10 figs., 10 tabs

  13. Diesel Particulate Matter Polygons, US EPA Region 9, 2005, NATA

    Data.gov (United States)

    U.S. Environmental Protection Agency — The national-scale assessment includes 177 air pollutants (a subset of the air toxics on the Clean Air Act's list of 187 air toxics plus diesel particulate matter...

  14. Observations on particulate organic nitrates and unidentified components of NOy

    DEFF Research Database (Denmark)

    Nielsen, T.; Egeløv, A.H.; Granby, K.

    1995-01-01

    A method to determine the total content of particulate organic nitrates (PON) has been developed and ambient air measurements of PON, NO, NO2, HNO3, peroxyacetyl nitrate (PAN), peroxypropionyl nitrate (PPN), gas NOy and particulate inorganic nitrate have been performed in the spring and early...... summer al an agricultural site in Denmark and compared with measurements of ozone, H2O2, SO2, formic acid, acetic acid and methane sulphonic acid. The gas NOy detector determines the sum NO + NO2 + HNO2 + HNO3 + PAN + PPN + gas phase organic nitrates + 2 x N2O5 + NO3. The content of residual gas NOy...... = gas NOy + particulate inorganic nitrate). Residual gas NOy was much higher than the particulate fraction of organic nitrates (PON). PON was only 0.25 +/- 0.11% of concentrations of photochemical oxidants in connection with high-pressure systems suggesting atmospheric processes being the major source...

  15. Life Support Systems: Trace Contaminant and Particulate Control

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced Exploration Systems (AES) Life Support Systems project Trace Contaminant and Particulate Control task: Work in the area of trace contamination and...

  16. Particulate Air Contamination in Puerto Rico: A Student Involvement Project.

    Science.gov (United States)

    Eckert, Richard R.

    1979-01-01

    Describes a research project undertaken by physics undergraduate students to monitor particulate air contamination in Ponce, Puerto Rico, and to determine the meteorological factors which contribute to it. (GA)

  17. Short term variations in particulate matter in Mahi river estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Rokade, M.A.; Zingde, M.D.

    The particulate matter (PM) collected from Mahi River Estuary was analysed for organic carbon (POC), nitrogen (PON), and chlorophyll a (Chl a). The concentration of PM, POC, PON and Chl a showed short term variations. Average surface concentration...

  18. Canada-United States Transboundary Particulate Matter Science Assessment 2013

    Science.gov (United States)

    This 2013 document summarizes the findings of the Canada-U.S. subcommittee on Scientific Cooperation concerning the transboundary transport of particulate matter (PM) and PM precursors between the two countries.

  19. Canada-United States Transboundary Particulate Matter Science Assessment

    Science.gov (United States)

    This 2004 document summarizes the findings of the Canada-U.S. subcommittee on Scientific Cooperation concerning the transboundary transport of particulate matter (PM) and PM precursors between the two countries.

  20. Dynamics of Charged Particulate Systems Modeling, Theory and Computation

    CERN Document Server

    Zohdi, Tarek I

    2012-01-01

    The objective of this monograph is to provide a concise introduction to the dynamics of systems comprised of charged small-scale particles. Flowing, small-scale, particles ("particulates'') are ubiquitous in industrial processes and in the natural sciences. Applications include electrostatic copiers, inkjet printers, powder coating machines, etc., and a variety of manufacturing processes. Due to their small-scale size, external electromagnetic fields can be utilized to manipulate and control charged particulates in industrial processes in order to achieve results that are not possible by purely mechanical means alone. A unique feature of small-scale particulate flows is that they exhibit a strong sensitivity to interparticle near-field forces, leading to nonstandard particulate dynamics, agglomeration and cluster formation, which can strongly affect manufactured product quality. This monograph also provides an introduction to the mathematically-related topic of the dynamics of swarms of interacting objects, ...

  1. Ocean subsurface particulate backscatter estimation from CALIPSO spaceborne lidar measurements

    Science.gov (United States)

    Chen, Peng; Pan, Delu; Wang, Tianyu; Mao, Zhihua

    2017-10-01

    A method for ocean subsurface particulate backscatter estimation from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite was demonstrated. The effects of the CALIOP receiver's transient response on the attenuated backscatter profile were first removed. The two-way transmittance of the overlying atmosphere was then estimated as the ratio of the measured ocean surface attenuated backscatter to the theoretical value computed from wind driven wave slope variance. Finally, particulate backscatter was estimated from the depolarization ratio as the ratio of the column-integrated cross-polarized and co-polarized channels. Statistical results show that the derived particulate backscatter by the method based on CALIOP data agree reasonably well with chlorophyll-a concentration using MODIS data. It indicates a potential use of space-borne lidar to estimate global primary productivity and particulate carbon stock.

  2. Transportation conformity particulate matter hot-spot air quality modeling.

    Science.gov (United States)

    2013-07-01

    In light of the new development in particulate matter (PM) hot-spot regulations and Illinois Department : of Transportation (IDOT)s National Environmental Policy Act (NEPA) documentation requirements, : this project is intended to (1) perform and ...

  3. Automated particulate sampler field test model operations guide

    Energy Technology Data Exchange (ETDEWEB)

    Bowyer, S.M.; Miley, H.S.

    1996-10-01

    The Automated Particulate Sampler Field Test Model Operations Guide is a collection of documents which provides a complete picture of the Automated Particulate Sampler (APS) and the Field Test in which it was evaluated. The Pacific Northwest National Laboratory (PNNL) Automated Particulate Sampler was developed for the purpose of radionuclide particulate monitoring for use under the Comprehensive Test Ban Treaty (CTBT). Its design was directed by anticipated requirements of small size, low power consumption, low noise level, fully automatic operation, and most predominantly the sensitivity requirements of the Conference on Disarmament Working Paper 224 (CDWP224). This guide is intended to serve as both a reference document for the APS and to provide detailed instructions on how to operate the sampler. This document provides a complete description of the APS Field Test Model and all the activity related to its evaluation and progression.

  4. Atmospheric oxidative chemistry of organic particulate emissions from fuel combustion.

    Science.gov (United States)

    2011-03-25

    "Construction and characterization of the University of Vermont Environmental Chamber (UVMEC) : were completed in this last phase of the project. The primary function of the UVMEC is to enable : tropospheric particulate formation and aging studies to...

  5. AIRWAY EPITHELIAL EFFECTS OF PARTICULATE POLLUTANTS: ROLE OF METAL INTERACTIONS

    Science.gov (United States)

    Numerous epidemiologic studies have demonstrated positive associations with particulate matter (PM) air pollution and daily respiratory morbidity - including exacerbations of asthma. Data are needed to elucidate which PM subcomponents may be mediating disease exacerbation in ind...

  6. Particulate emission abatement for Krakow boiler houses

    Energy Technology Data Exchange (ETDEWEB)

    Wysk, R.

    1995-12-31

    Among the many strategies for improving air quality in Krakow, one possible method is to adapt new and improved emission control technology. This project focuses on such a strategy. In order to reduce dust emissions from coal-fueled boilers, a new device called a Core Separator has been introduced in several boiler house applications. This advanced technology has been successfully demonstrated in Poland and several commercial units are now in operation. Particulate emissions from the Core Separator are typically 3 to 5 times lower than those from the best cyclone collectors. It can easily meet the new standard for dust emissions which will be in effect in Poland after 1997. The Core Separator is a completely inertial collector and is based on a unique recirculation method. It can effectively remove dust particles below 10 microns in diameter, the so-called PM-10 emissions. Its performance approaches that of fabric filters, but without the attendant cost and maintenance. It is well-suited to the industrial size boilers located in Krakow. Core Separators are now being marketed and sold by EcoInstal, one of the leading environmental firms in Poland, through a cooperative agreement with LSR Technologies.

  7. Evaluation of principal cannabinoids in airborne particulates

    Energy Technology Data Exchange (ETDEWEB)

    Balducci, C [Italian National Research Council, Institute for Atmospheric Pollution (CNR-IIA), Monterotondo Stazione (Italy); Nervegna, G; Cecinato, A [Italian National Research Council, Institute for Atmospheric Pollution (CNR-IIA), Monterotondo Stazione (Italy)

    2009-05-08

    The determination of delta(9)-tetrahydrocannabinol ({Delta}{sup 9}-THC), cannabidiol (CND) and cannabinol (CNB), primary active components in cannabis preparation, was carried out on airborne particulates by applying a specific procedure consisting of soot extraction by ultrasonic bath, purification by solvent partitioning, derivatization with N-(t-butyldimethylsilyl)-N-methyl-trifluoroacetamide, and separation/detection through gas chromatography coupled with tandem mass spectrometry. The optimized procedure was found suitable for measuring the three psychotropic substances at concentrations ranging from ca. 0.001 to ca. 5.0 ng cm{sup -3} of air, with recoveries always higher than 82%, accuracy >7.3% and precision >90%. Application of the procedure performed on field in Rome and Bari, Italy, demonstrated that all three compounds contaminate the air in Italian cities whereas in Algiers, Algeria, only cannabinol, the most stable in the atmosphere, exceeded the limit of quantification of the method. The relative percentages of the three cannabinoids in general reproduced those typical of the Cannabis sativa plant and were very different from those found in human blood, urine and sweat.

  8. Airborne particulate matter and spacecraft internal environments

    Science.gov (United States)

    Liu, Benjamin Y. H.; Rubow, Kenneth L.; Mcmurry, Peter H.; Kotz, Thomas J.; Russo, Dane

    1991-01-01

    Instrumentation, consisting of a Shuttle Particle Sampler (SPS) and a Shuttle Particle Monitor (SPM), has been developed to characterize the airborne particulate matter in the Space Shuttle cabin during orbital flight. The SPS size selectively collects particles in four size fractions (0-2.5, 2.5-10, 10-100, and greater than 100 microns) which are analyzed postflight for mass concentration and size distribution, elemental composition, and morphology. The SPM provides a continuous record of particle concentration through photometric light scattering. Measurements were performed onboard Columbia, OV-102, during the flight of STS-32 in January 1990. No significant changes were observed in the particle mass concentration, size distribution, or chemical composition in samples collected during flight-day 2 and flight-day 7. The total mass concentration was 56 microg/cu cm with approximately half of the particles larger than 100 microns. Elemental analysis showed that roughly 70 percent of the particles larger than 2.5 microns were carbonaceous with small amounts of other elements present. The SPM showed no temporal or spatial variation in particle mass concentration during the mission.

  9. Metal/nonmetal diesel particulate matter rule

    Energy Technology Data Exchange (ETDEWEB)

    Tomko, D.M. [United States Dept. of Labor, Mine Safety and Health Administration, Pittsburgh, PA (United States). Safety and Health Technology Center; Stackpole, R.P. [United States Dept. of Labor, Mine Safety and Health Administration, Triadelphia, WV (United States). Approval and Certification Center; Findlay, C.D. [United States Dept. of Labor, Mine Safety and Health Administration, Arlington, VA (United States). Metal/Nonmetal Safety and Health; Pomroy, W.H. [United States Dept. of Labor, Mine Safety and Health Administration, Duluth, MN (United States). Metal/Nonmetal North Central District

    2010-07-01

    The American Mine Safety and Health Administration (MSHA) issued a health standard in January 2001 designed to reduce exposure to diesel particulate matter (DPM) in underground metal and nonmetal mines. The rule established an interim concentration limit for DPM of 400 {mu}g/m{sup 3} of total carbon, to be followed in 2004 by a final limit of 160 {mu}g/m{sup 3} of total carbon. The 2001 rule was challenged in federal court by various mining trade associations and mining companies. The rule was subsequently amended. This paper highlighted the major provisions of the 2006 final rule and summarized MSHAs current compliance sampling procedures. The concentration limit was changed to a permissible exposure limit and the sampling surrogate was changed from total carbon to elemental carbon. The MSHA published a new rule in 2006 which based the final limit on a miner's personal exposure rather than a concentration limit. The final limit was phased in using 3 steps over 2 years. This paper also discussed engineering controls and a recent MSHA report on organic carbon, elemental carbon and total carbon emissions from a diesel engine fueled with various blends of standard diesel and biodiesel. In May 2008, about two-thirds of all underground metal/nonmetal mines achieved and maintained compliance with the rule. 20 refs.

  10. Evaluation of principal cannabinoids in airborne particulates

    International Nuclear Information System (INIS)

    Balducci, C.; Nervegna, G.; Cecinato, A.

    2009-01-01

    The determination of delta(9)-tetrahydrocannabinol (Δ 9 -THC), cannabidiol (CND) and cannabinol (CNB), primary active components in cannabis preparation, was carried out on airborne particulates by applying a specific procedure consisting of soot extraction by ultrasonic bath, purification by solvent partitioning, derivatization with N-(t-butyldimethylsilyl)-N-methyl-trifluoroacetamide, and separation/detection through gas chromatography coupled with tandem mass spectrometry. The optimized procedure was found suitable for measuring the three psychotropic substances at concentrations ranging from ca. 0.001 to ca. 5.0 ng cm -3 of air, with recoveries always higher than 82%, accuracy >7.3% and precision >90%. Application of the procedure performed on field in Rome and Bari, Italy, demonstrated that all three compounds contaminate the air in Italian cities whereas in Algiers, Algeria, only cannabinol, the most stable in the atmosphere, exceeded the limit of quantification of the method. The relative percentages of the three cannabinoids in general reproduced those typical of the Cannabis sativa plant and were very different from those found in human blood, urine and sweat.

  11. PARTICULATE EMISSION ABATEMENT FOR KRAKOW BOILERHOUSES

    Energy Technology Data Exchange (ETDEWEB)

    Bruce H. Easom; Leo A, Smolensky; S. Ronald Wysk; Jan Surowka; Miroslaw Litke; Jacek Ginter

    1998-09-30

    A U.S./Polish Bilateral Steering Committee (BSC) and the Department of Energy (DOE) selected LSR Technologies, Inc. as a contractor to participate in the Krakow Clean Fuels and Energy Efficiency Program. The objective of this program was the formation of business ventures between U.S. and Polish firms to provide equipment and services to reduce air emissions in the city of Krakow. A cooperative agreement was entered into by DOE and LSR to begin work in April 1994 involving implementation of particulate control technology called a Core Separator{trademark} for coal-fueled boilerhouses in the city. The major work tasks included: (1) conducting a market analysis, (2) completion of a formal marketing plan, (3) obtaining patent protection within Poland, (4) selecting a manufacturing partner, and (5) completing a demonstration unit and commercial installations. In addition to work performed by LSR Technologies, key contributors to this project were (1) the Polish Foundation for Energy Efficiency (FEWE), a non-profit consulting organization specializing in energy and environmental-related technologies, and (2) EcoInstal, a privately held Polish company serving the air pollution control market. As the project concluded in late 1998, five (5) Core Separator{trademark} installations had been implemented in the city of Krakow, while about 40 others were completed in other regions of Poland.

  12. Gene-particulate matter-health interactions

    International Nuclear Information System (INIS)

    Kleeberger, Steven R.; Ohtsuka, Yoshinori

    2005-01-01

    Inter-individual variation in human responses to air pollutants suggests that some subpopulations are at increased risk to the detrimental effects of pollutant exposure. Extrinsic factors such as previous exposure and nutritional status may influence individual susceptibility. Intrinsic (host) factors that determine susceptibility include age, gender, and pre-existing disease (e.g., asthma), and it is becoming clear that genetic background also contributes to individual susceptibility. Environmental exposures to particulates and genetic factors associated with disease risk likely interact in a complex fashion that varies from one population and one individual to another. The relationships between genetic background and disease risk and severity are often evaluated through traditional family-based linkage studies and positional cloning techniques. However, case-control studies based on association of disease or disease subphenotypes with candidate genes have advantages over family pedigree studies for complex disease phenotypes. This is based in part on continued development of quantitative analysis and the discovery and availability of simple sequence repeats and single nucleotide polymorphisms. Linkage analyses with genetically standardized animal models also provide a useful tool to identify genetic determinants of responses to environmental pollutants. These approaches have identified significant susceptibility quantitative trait loci on mouse chromosomes 1, 6, 11, and 17. Physical mapping and comparative mapping between human and mouse genomes will yield candidate susceptibility genes that may be tested by association studies in human subjects. Human studies and mouse modeling will provide important insight to understanding genetic factors that contribute to differential susceptibility to air pollutants

  13. Particulate Emissions and Biodiesel: A review

    Directory of Open Access Journals (Sweden)

    Michal Angelovič

    2013-05-01

    Full Text Available Abstract The current mode of transport using fuel it cannot be characterized as harmless to human health or as sustainable. The whole process of extracting, processing and using of petroleum products can be seen as the raw material cycle in nature. This cycle also cause serious damage to the environment and human health. Many studies on air pollutant emissions with biodiesel have been carried out worldwide. Studies have shown that diesel-powered vehicles are the major contributors of PM emissions. PM particulates are especially important in regard to adverse health outcomes, such as increased cardiovascular, respiratory morbidity and mortality rates, due to their larger active surface and the higher likelihood of deposition in the alveolar region of the lungs. Hence, it is overwhelming argument that the use of biodiesel instead of diesel causes reduce of PM emissions. Of course, this reduction will become smaller with the reduction of biodiesel proportion in the blended fuel. The trend with which PM emissions of biodiesel will be reduced, is due to lower aromatic and sulfur compounds and higher cetane number for biodiesel, but the more important factor is the higher oxygen content.

  14. Fine particulate pollution and asthma exacerbations.

    Science.gov (United States)

    Bouazza, Naïm; Foissac, Frantz; Urien, Saik; Guedj, Romain; Carbajal, Ricardo; Tréluyer, Jean-Marc; Chappuy, Hélène

    2017-12-19

    As the results from epidemiological studies about the impact of outdoor air pollution on asthma in children are heterogeneous, our objective was to investigate the association between asthma exacerbation in children and exposure to air pollutants. A database of 1 264 585 paediatric visits during the 2010-2015 period to the emergency rooms from 20 emergency departments (EDs) of 'Assistance Publique Hôpitaux de Paris (APHP)', the largest hospital group in Europe, was used. A total of 47 107 visits were classified as asthma exacerbations. Concentration of air pollutants (nitrogen dioxide, ozone, fine particulate matter (PM) with an aerodynamic diameter smaller than 10  µm (PM 10 ) and 2.5 µm (PM 2.5 )), as well as meteorological data, evolution of respiratory syncytial virus infection and pollen exposition, were collected on an hourly or daily basis for the same period using institutional databases. To assess the association between air pollution and asthma, mixed-effects quasi-Poisson regression modelling was performed. The only compound independently associated with ED visits for asthma was PM 2.5 (Ppollutants. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  15. Particulate COD balance of particulate cod in eletrocuagulation/flotation reactor treating tannery effluent

    Directory of Open Access Journals (Sweden)

    Rodrigo Babora Borri

    2012-04-01

    Full Text Available Mass balance or particulate organic matter was studied in terms of COD, by means of electrocoagulation/flotation (ECF reactor treating tannery effluent. Reactor was operated in fill and draw (batch mode. Operating in hydraulic residence time of 65 minutes, ECF reactor reached 55 % COD removal. Although volatile solids were also removed from liquid phase (removal of 40%, fixed solids concentration, and hence total solids concentration, showed to be higher in withdrawn effluent than in ECF’s influent. This was assigned to NaCl added in order to enhance conductivity in wastewater.

  16. Inventory of primary particulates emissions; Inventaire des emissions de particules primaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-12-01

    CITEPA carried out a national inventory on particulate emissions. This report presents the results of this study for a great number of sectors and it covers a larger number of sources than the previous CITEPA inventories on particles and some other inventories carried out by International organisms (TNO, IIASA). In particular, at the present time, fugitive dust emissions for some sources are rarely taken into account in inventories because of poor knowledge and they are still the subject of researches in order to validate the emission results. (author)

  17. Exposure to Particulate Hexavalent Chromium Exacerbates Allergic Asthma Pathology

    Science.gov (United States)

    Schneider, Brent C.; Constant, Stephanie L.; Patierno, Steven R.; Jurjus, Rosalyn A.; Ceryak, Susan M.

    2011-01-01

    Airborne hexavalent chromate, Cr(VI), has been identified by the Environmental Protection Agency as a possible health threat in urban areas, due to the carcinogenic potential of some of its forms. Particulate chromates are produced in many different industrial settings, with high levels of aerosolized forms historically documented. Along with an increased risk of lung cancer, a high incidence of allergic asthma has been reported in workers exposed to certain inhaled particulate Cr(VI) compounds. However, a direct causal association between Cr(VI) and allergic asthma has not been established. We recently showed that inhaled particulate Cr(VI) induces an innate neutrophilic inflammatory response in BALB/c mice. In the current studies we investigated how the inflammation induced by inhaled particulate Cr(VI) might alter the pathology of an allergic asthmatic response. We used a well-established mouse model of allergic asthma. Groups of ovalbumin protein (OVA)-primed mice were challenged either with OVA alone, or with a combination of OVA and particulate zinc chromate, and various parameters associated with asthmatic responses were measured. Co-exposure to particulate Cr(VI) and OVA mediated a mixed form of asthma in which both eosinophils and neutrophils are present in airways, tissue pathology is markedly exacerbated, and airway hyperresponsiveness is significantly increased. Taken together these findings suggest that inhalation of particulate forms of Cr(VI) may augment the severity of ongoing allergic asthma, as well as alter its phenotype. Such findings may have implications for asthmatics in settings in which airborne particulate Cr(VI) compounds are present at high levels. PMID:22178736

  18. Zone heated inlet ignited diesel particulate filter regeneration

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2012-06-26

    An exhaust system that processes exhaust generated by an engine is provided. The system includes: a particulate filter (PF) that is disposed downstream of the engine and that filters particulates from the exhaust; and a grid that includes electrically resistive material that is segmented by non-conductive material into a plurality of zones and wherein the grid is applied to an exterior upstream surface of the PF.

  19. Large impact of small particulates; Grote invloed van klein fijnstof

    Energy Technology Data Exchange (ETDEWEB)

    Hiemstra-Holtkamp, I.V.L. [Astma Fonds, Leusden (Netherlands)

    2006-06-15

    PM2.5 particulates are responsible for a large part of thousands of people that die of air pollution. The Asthma Fund in the Netherlands wants the Dutch government to take specific action and measures for those small particulates. [Dutch] PM2.5 is verantwoordelijk voor een groot deel van de 1000-en mensen die elk jaar sterven door luchtverontreiniging. Het Astma Fonds wil dat de overheid aparte maatregelen neemt voor PM2.5.

  20. K-Basins particulate water content, and behavior

    International Nuclear Information System (INIS)

    DUNCAN, D.R.

    1999-01-01

    This analysis summarizes the state of knowledge of K-basins spent nuclear fuel oxide (film, particulate or sludge) and its chemically bound water in order to estimate the associated multi-canister overpack (MCO) water inventory and to describe particulate dehydration behavior. This information can be used to evaluate the thermal and chemical history of an MCO and its contents during cold vacuum drying (CVD), shipping, and interim storage

  1. K-Basins particulate water content, and behavior

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAN, D.R.

    1999-02-25

    This analysis summarizes the state of knowledge of K-basins spent nuclear fuel oxide (film, particulate or sludge) and its chemically bound water in order to estimate the associated multi-canister overpack (MCO) water inventory and to describe particulate dehydration behavior. This information can be used to evaluate the thermal and chemical history of an MCO and its contents during cold vacuum drying (CVD), shipping, and interim storage.

  2. Particulate matter mass concentrations produced from pavement surface abrasion

    Directory of Open Access Journals (Sweden)

    Fullova Dasa

    2017-01-01

    Full Text Available According to the latest findings particulate matter belong to the most significant pollutants in Europe together with ground-level ozone O3 and nitrogen dioxide NO2. Road traffic is one of the main sources of particulate matter. Traffic volume has unpleasant impact on longevity of the pavements and also on the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The paper deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The paper offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

  3. Domestic smoke exposure is associated with alveolar macrophage particulate load.

    Science.gov (United States)

    Fullerton, Duncan G; Jere, Khuzwayo; Jambo, Kondwani; Kulkarni, Neeta S; Zijlstra, Eduard E; Grigg, Jonathan; French, Neil; Molyneux, Malcolm E; Gordon, Stephen B

    2009-03-01

    Indoor air pollution is associated with impaired respiratory health. The pre-dominant indoor air pollutant to which two billion of the world's population is exposed is biomass fuel smoke. We tested the hypothesis that reported smoke exposure in men and women is associated with increased alveolar macrophage uptake of biomass smoke particulates. Healthy volunteers attending for research bronchoscopy in Malawi completed a questionnaire assessment of smoke exposure. Particulate matter visible in alveolar macrophages (AM) was quantified using digital image analysis. The geometric mean of the percentage area of the cytoplasm occupied by particulates in 50 cover-slip adherent AM was calculated and termed particulate load. In 57 subjects (40 men and 17 women) there was a significant difference between the particulate load in groups divided according to pre-dominant lighting form used at home (ANOVA P = 0.0009) and type of cooking fuel (P = 0.0078). Particulate load observed in macrophages is associated with the reported type of biomass fuel exposure. Macrophage function in relation to respiratory health should now be investigated in biomass smoke exposed subjects.

  4. Method and apparatus for removing volatile hydrocarbons from particulate soils

    International Nuclear Information System (INIS)

    Mendenhall, R.L.

    1992-01-01

    This patent describes an apparatus for heating solid particulate mineral compositions. It comprises: a counterflow ratable drum having a first end and an opposite second end, a first portion of the drum extending from the first end for a first length and having a first diameter along the first length, and a second portion of the drum secured to and extending from the first portion to the second end for a second length and having a second diameter along the second length, the second diameter being less than the first diameter, a burner adjacent the first end for introducing and directing hot gases of combustion into the first portion of the drum toward the second end, means for introducing particulate composition into the drum at the second end, means for directing the particulate composition along the drum from the second end toward the first end, and means for recovering composition at the first end, means for removing a gaseous mixture of organic volatiles, gases of combustion and fine particles of the particulate composition adjacent the second drum end, means for separating fine particles of the particulate composition from the gaseous mixture, and means for returning the separated fine particulate composition particles to the first portion of the drum

  5. An evaluation of fuels and retrofit diesel particulate filters to reduce diesel particulate matter emissions in an underground mine

    CSIR Research Space (South Africa)

    Wattrus, MC

    2016-09-01

    Full Text Available Through an industry wide collaborative project, this paper explores what potential exists for South African underground mines to reduce diesel particulate emissions, where the starting point is a mine using older engine technology (Tier 1 emission...

  6. Thorium-particulate matter interaction. Thorium complexing capacity of oceanic particulate matter: Theory

    International Nuclear Information System (INIS)

    Hirose, Katsumi; Tanque, Eiichiro

    1994-01-01

    The interaction between thorium and oceanic particulate matter was examined experimentally by using chemical equilibrium techniques. Thorium reacts quantitatively with the organic binding site of Particulate Matter (PM) in 0.1 mol/L HCl solution by complexation, which is equilibrated within 34 h. According to mass balance analysis, thorium forms a 1:1 complex with the organic binding site in PM, whose conditional stability constant is 10 6.6 L/mol. The Th adsorption ability is present even in 6.9 mol/L HCl solution although the amount of Th adsorption decreases with increasing acidity in the solution. Interferences to Th adsorption by Fe(III) suggests that other metals cannot react with PM in more than 0.1 mol/L HCl solutions when concentrations of other metals are the same level of Th. The competitive reaction between Th and Fe(III) occurs in higher Fe concentrations, which means that the organic binding site is nonspecific for Th. A vertical profile of Th complexing capacity of PM in the western North Pacific is characterized; that is, the Th complexing capacity shows a surface maximum and decreases rapidly with depth

  7. Les Basaltes de l’Atlas de Béni-Mellal (Haut Atlas Central, Maroc : un Volcanisme Transitionnel Intraplaque Associé aux Stades de L’évolution Géodynamique du Domaine Atlasique

    Directory of Open Access Journals (Sweden)

    Jaouad Guezal

    2013-07-01

    Full Text Available Les roches basaltiques de l’Atlas de Béni-Mellal (Haut-Atlas Central, Maroc, mises en place, dans les différents bassins synclinaux de la région, se manifestent en deux horizons volcaniques B1 et B2. Les deux événements éruptifs sont d’âge Jurassique moyen pour les coulées de l’horizon B1 et d’âge Crétacé inférieur pour celles de l’horizon B2. Les roches sont caractérisées par un faciès des basaltes à olivines. La composition de leurs clinopyroxènes est marquée par deux tendances : augite au niveau des basaltes à olivine du B1 et diopside au niveau de ceux du B2. La composition géochimique sur roche totale dévoile le caractère transitionnel de ces roches. La relative dissimilitude géochimique signalée au niveau des basaltes des deux horizons peut être expliquée par un début du changement de la nature du magmatisme de la région en relation avec l’évolution géodynamique du domaine atlasique.

  8. Les déterminants de l’attractivité territoriale des entreprises manufacturières et logistiques étrangères : application à la ville de Tanger – Maroc

    Directory of Open Access Journals (Sweden)

    Abbes Elhasbi

    2017-03-01

    Full Text Available L’objectif de cet article est de proposer les principaux facteurs d’attractivité des investisseurs étrangers dans les secteurs manufacturiers et logistiques de la ville de Tanger au Maroc. Notre modèle conceptuel a été élaboré à partir d’une revue de littérature et d’entretiens avec un échantillon de dirigeants des petites et moyennes entreprises (PME étrangères. Notre analyse empirique est réalisée à partir des données issues d’une enquête menée auprès des dirigeants des entreprises étrangères (manufacturières et logistiques installées à la ville de Tanger. L’utilisation de l’approche Partial least squares (PLS nous a permis de tester les liens de causalité entre les divers facteurs politiques, économiques, sociaux, technologiques, environnementaux et juridiques (Pestel. L’intérêt scientifique de notre modèle est de présenter aux décideurs de la ville de Tanger des recommandations afin d’améliorer le développement et l’attractivité des investissements étrangers dans les deux secteurs logistique et manufacturier.

  9. Atmospheric particulate matter within the Sudbury footprint

    Energy Technology Data Exchange (ETDEWEB)

    Koski, P. [Laurentian Univ., Sudbury, ON (Canada); Spiers, G.A. [Laurentian Univ., Sudbury, ON (Canada). Centre for Environmental Monitoring

    2007-07-01

    In order to assess health and risks to ecosystems, measuring exposure to coarse, fine and ultrafine dust and their association with metals in the air is necessary. This paper presented the results of a study that investigated the concentration, particle size distribution and spatial dispersion of metals in total and fractioned airborne dust. The study involved collection of airborne dust samples at five different sites over a one year period in the Sudbury area, including one control site located downwind of the south-westerly most industrial emission source. The paper discussed the goals and objectives of the project which included analysis of total concentration of particulate matter (PM) within various size fractions; analysis of concentration of selected metals such as arsenic, zinc, copper, nickel, cobalt, iron, manganese, chromium and lead as well as the species of sulphur within those size fractions; delineation between particle chemistry of both short and long range transport origin; determining the effects of the different seasons on PM concentrations, and establish any seasonal/temperature trends that may occur. The paper also discussed the methodology for the study with reference to sampling sites, sampling equipment, sampling schedule, mass determination, and chemical analysis. X-ray Fluorescence (XRF) was used to determine the total metals concentration in airborne dust. The results of the study were also presented. It was concluded that PM analysis within the Sudbury footprint indicated that the finer fractions primarily contained the highest weight and metal concentration. In addition, sulphate seemed to be the only species of sulphur present in the different size fractions at each site. 22 refs., 4 tabs., 5 figs.

  10. Nano indentation of particulate and polymer films

    International Nuclear Information System (INIS)

    Akram, Aisha

    2001-01-01

    A detailed knowledge of the formation and rupture mechanisms of agglomerates is essential when seeking to model equipment designed to produce and process such agglomerated particulate solids. In the work to be described the nano-indentation of two-dimensional agglomerate films was carried out in order to establish a means of identifying the generic breakage mechanisms of agglomerated systems. Data analysis techniques are developed that enable the individual inter-particle junction strengths to be calculated for a model system consisting of rather mono-dispersed colloidal silica particles (20-24 nm diameter) bound with a poly(methyl methacrylate). Applied load and penetration depth data in the range (10 mN and 500 nm respectively) are provided as a function of loading time during a continuous loading. It is argued that these data enable the sequence of the discrete binder bridge failures to be observed thus giving a quantitative indication of the breakage mechanism of this agglomerate system as well as reflect the agglomerate structure. The secondary objective of this work was to produce a range of agglomerates with different mechanical properties, without changing the type and amount of binder or prime particles used in the system. This was achieved by altering the mechanical properties of the binder, poly(methyl methacrylate), by the use of a variety of solvents. From data obtained using nano-indentation on thin films of the treated polymer, brittle and ductile forms of poly(methyl methacrylate) could be distinguished. These trends are reflected, to some degree, in the mechanical response of the agglomerated layers. (author)

  11. Polycyclic Aromatic Hydrocarbons in Fine Particulate Matter ...

    Science.gov (United States)

    This study measured polycyclic aromatic hydrocarbon (PAH) composition in particulate matter emissions from residential cookstoves. A variety of fuel and cookstove combinations were examined, including: (i) liquid petroleum gas (LPG), (ii) kerosene in a wick stove, (iii) wood (10% and 30% moisture content on a wet basis) in a forced-draft fan stove, and (iv) wood in a natural-draft rocket cookstove. LPG combustion had the highest thermal efficiency (~57%) and the lowest PAH emissions per unit fuel energy, resulting in the lowest PAH emissions per useful energy delivered (MJd). The average benzo[a]pyrene (B[a]P) emission factor for LPG was 0.842 µg/MJd; the emission rate was 0.043 µg/min. The highest PAH emissions were from wood burning in the natural-draft stove (209-700 µg B[a]P/MJd). PAH emissions from kerosene were significantly lower than those from the wood burning in the natural-draft cookstove, but higher than those from LPG. It is expected that in rural regions where LPG and kerosene are unavailable or unaffordable, the forced-draft fan stove may be an alternative because its emission factor (5.17-8.07 µg B[a]P/MJd) and emission rate (0.52-0.57 µg/min) are similar to kerosene (5.36 µg B[a]P/MJd and 0.45 µg/min). Compared with wood combustion emissions, LPG stoves emit less total PAH emissions and less fractions of high molecular weight PAHs. Relatively large variations in PAH emissions from LPG call for additional future tests to identify the major

  12. Atmospheric particulate matter within the Sudbury footprint

    International Nuclear Information System (INIS)

    Koski, P.; Spiers, G.A.

    2007-01-01

    In order to assess health and risks to ecosystems, measuring exposure to coarse, fine and ultrafine dust and their association with metals in the air is necessary. This paper presented the results of a study that investigated the concentration, particle size distribution and spatial dispersion of metals in total and fractioned airborne dust. The study involved collection of airborne dust samples at five different sites over a one year period in the Sudbury area, including one control site located downwind of the south-westerly most industrial emission source. The paper discussed the goals and objectives of the project which included analysis of total concentration of particulate matter (PM) within various size fractions; analysis of concentration of selected metals such as arsenic, zinc, copper, nickel, cobalt, iron, manganese, chromium and lead as well as the species of sulphur within those size fractions; delineation between particle chemistry of both short and long range transport origin; determining the effects of the different seasons on PM concentrations, and establish any seasonal/temperature trends that may occur. The paper also discussed the methodology for the study with reference to sampling sites, sampling equipment, sampling schedule, mass determination, and chemical analysis. X-ray Fluorescence (XRF) was used to determine the total metals concentration in airborne dust. The results of the study were also presented. It was concluded that PM analysis within the Sudbury footprint indicated that the finer fractions primarily contained the highest weight and metal concentration. In addition, sulphate seemed to be the only species of sulphur present in the different size fractions at each site. 22 refs., 4 tabs., 5 figs

  13. On-road particulate emission measurement

    Science.gov (United States)

    Mazzoleni, Claudio

    Particulate matter (PM) suspended in the atmosphere has harmful health effects, contributes to visibility impairment, and affects atmospheric radiative transfer, thereby contributing to global change. Vehicles contribute substantially to the ambient PM concentration in urban areas, yet the fraction of ambient PM originating from vehicle emissions is poorly characterized because suitable measurement methods have not been available. This dissertation describes the development and the use of a new vehicle emission remote sensing system (VERSS) for the on-road measurement of PM emission factors for vehicles. The PM VERSS measures PM by ultraviolet backscattering and transmission. PM backscattering and transmission mass efficiencies have been calculated from Mie theory based on an homogeneous spherical model for gasoline particles and on a two-layers, spherical model for diesel particles. The VERSS was used in a large-scale study in Las Vegas, NV. A commercial gaseous VERSS was used for the measurement of gaseous emission factors (i.e., carbon monoxide, hydrocarbons, and nitrogen oxide). Speed and acceleration were also measured for each vehicle. A video image of each vehicle's rear license plate was acquired and license plate numbers were matched with the Clark County department of motor vehicle database to retrieve vehicle information such as model year, vehicle weight category and engine ignition type. PM VERSS has precisely estimated PM fleet average emission factors and clearly shown the dependence of PM emission factors on vehicle model year. Under mostly hot-stabilized operation, diesel vehicle PM emission factors are about 25 times higher than those of gasoline vehicles. Furthermore, the fleet frequency distributions of PM emission factors are highly skewed, meaning that most of the fleet emission factor is accounted for by a small portion of the fleet. The PM VERSS can measure PM emission factors for these high emitting vehicles on an individual basis. PM

  14. Diesel engine exhaust particulate filter with intake throttling incineration control

    Energy Technology Data Exchange (ETDEWEB)

    Ludecke, O.; Rosebrock, T.

    1980-07-08

    A description is given of a diesel engine exhaust filter and particulate incineration system in combination with a diesel engine having a normally unthrottled air induction system for admitting combustion air to the engine and an exhaust system for carrying off spent combustion products exhausted from the engine, said filter and incineration system comprising: a combustion resistant filter disposed in the exhaust system and operative to collect and retain portions of the largely carbonaceous particulate matter contained in the engine exhaust products, said fiber being capable of withstanding without substantial damage internal temperatures sufficient to burn the collected particulate matter, a throttle in the indication system and operable to restrict air flow into the engine to reduce the admittance of excess combustion air and thereby increase engine exhaust gas temperature, and means to actuate said throttle periodically during engine operation to an air flow restricting burn mode capable of raising the particulates in said filter to their combustion temperature under certain engine operating conditions and to maintain said throttle mode for an interval adequate to burn retained particulates in the filter.

  15. Laboratory Measurements of Particulate Matter Concentrations from Asphalt Pavement Abrasion

    Directory of Open Access Journals (Sweden)

    Fullová Daša

    2016-12-01

    Full Text Available The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

  16. Semivolatile Particulate Organic Material Southern Africa during SAFARI 2000

    Science.gov (United States)

    Eatough, D. J.; Eatough, N. L.; Pang, Y.; Sizemore, S.; Kirchstetter, T. W.; Novakov, T.

    2005-01-01

    During August and September 2000, the University of Washington's Cloud and Aerosol Research Group (CARG) with its Convair-580 research aircraft participated in the Southern African Fire-Atmosphere Research Initiative (SAFARI) 2000 field study in southern Africa. Aboard this aircraft was a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS), which was used to determine semivolatile particulate material with a diffusion denuder sampler. Denuded quartz filters and sorbent beds in series were used to measure nonvolatile and semivolatile materials, respectively. Results obtained with the PC-BOSS are compared to those obtained with conventional quartz-quartz and Teflon-quartz filter pack samplers. Various 10-120 min integrated samples were collected during flights through the h e troposphere, in the atmospheric boundary layer, and in plumes from savanna fires. Significant fine particulate semivolatile organic compounds (SVOC) were found in all samples. The SVOC was not collected by conventional filter pack samplers and therefore would not have been determined in previous studies that used only filter pack samplers. The SVOC averaged 24% of the fine particulate mass in emissions from the fires and 36% of the fine particulate mass in boundary layer samples heavily impacted by aged emissions from savanna fires. Concentrations of fine particulate material in the atmospheric mixed layer heavily impacted by aged savanna frre emissions averaged 130 micrograms per cubic meter. This aerosol was 85% carbonaceous mated.

  17. Identification and Characterization of Particulate Matter Concentrations at Construction Jobsites

    Directory of Open Access Journals (Sweden)

    Ingrid P. S. Araújo

    2014-11-01

    Full Text Available The identification and characterization of particulate matter (PM concentrations from construction site activities pose major challenges due to the diverse characteristics related to different aspects, such as concentration, particle size and particle composition. Moreover, the characterization of particulate matter is influenced by meteorological conditions, including temperature, humidity, rainfall and wind speed. This paper is part of a broader investigation that aims to develop a methodology for assessing the environmental impacts caused by the PM emissions that arise from construction activities. The objective of this paper is to identify and characterize the PM emissions on a construction site with different aerodynamic diameters (PM2.5, PM10, total suspended particulates (TSP, based on an exploratory study. Initially, a protocol was developed to standardize the construction site selection criteria, laboratory procedures, field sample collection and laboratory analysis. This protocol was applied on a multifamily residential building construction site during three different construction phases (earthworks, superstructure and finishings aimed at measuring and monitoring PM concentrations arising from construction activities. The particulate matter was characterized in different particle sizes. Results showed that the higher TSP emissions arising from construction activities provoked environmental impacts. Some limitations to the results were identified, especially with regards the need for a detailed investigation about the influence of different construction phases on PM emissions. The findings provided significant knowledge about various situations, serving as a basis for improving the existing methodology for particulate material collection on construction sites and the development of future studies on the specific construction site phases.

  18. Evaluation of airborne particulates and fungi during hospital renovation.

    Science.gov (United States)

    Overberger, P A; Wadowsky, R M; Schaper, M M

    1995-07-01

    This study was conducted over 30 weeks on a hospital floor undergoing partial renovation. Some patients housed on the floor were immunosuppressed, including bone marrow transplant recipients. The construction zone was placed under negative pressure and was separated from patient rooms by existing hospital walls and via erection of a temporary barrier. Other control measures minimized patient exposure to airborne materials. Air sampling was done for 3 weeks prior to construction, 24 weeks during construction, and 3 weeks after renovation was completed. Airborne particulate concentrations, total spore counts, particle size, and fungal species were assessed. At the beginning of the renovation there were increases in airborne particulates (from 0.2 to 2.0 mg/m3) and fungal spores (from 3.5 to 350 colony forming units (CFU/m3), but only in the construction zone. Throughout the remainder of the renovation, particulate and fungal spore levels fluctuated inside the construction zone but remained close to baseline values in the patient area. When renovation was completed, particulates and spore counts inside the construction zone decreased to preconstruction levels. The primary fungus isolated from air samples was Penicillium. This study demonstrated that control measures were effective in reducing exposures of hospitalized patients to airborne particulates and spores and in reducing the increased risk of aspergillosis and other fungal infections associated with hospital construction projects. The data from this study may be useful in establishing exposure guidelines for other health care settings.

  19. Generalized Effective Medium Theory for Particulate Nanocomposite Materials

    Directory of Open Access Journals (Sweden)

    Muhammad Usama Siddiqui

    2016-08-01

    Full Text Available The thermal conductivity of particulate nanocomposites is strongly dependent on the size, shape, orientation and dispersion uniformity of the inclusions. To correctly estimate the effective thermal conductivity of the nanocomposite, all these factors should be included in the prediction model. In this paper, the formulation of a generalized effective medium theory for the determination of the effective thermal conductivity of particulate nanocomposites with multiple inclusions is presented. The formulated methodology takes into account all the factors mentioned above and can be used to model nanocomposites with multiple inclusions that are randomly oriented or aligned in a particular direction. The effect of inclusion dispersion non-uniformity is modeled using a two-scale approach. The applications of the formulated effective medium theory are demonstrated using previously published experimental and numerical results for several particulate nanocomposites.

  20. The electromagnetic and acoustic properties of smoke particulates

    International Nuclear Information System (INIS)

    Churches, D.K.

    1999-10-01

    The research work explores the Electromagnetic and Acoustic Properties of Smoke Particulates from real fires, and the initial development of an alternative method of smoke detection based on the study work. The research was entirely self-funded including the purchase of the experimental apparatus, test equipment and calibration to international standards. The study includes the properties of solid and liquid post combustion particulates in air suspension forming smoke plumes, and the associated fluid flow dynamics. As part of the study the electromagnetic and acoustic properties of smoke particulates, a somewhat unique detection method described as the ''Double Matrix Board System'' was developed and used. It was initially developed to assist in the electromagnetic study work, and was later modified to examine the acoustic properties. The published results of the research on the ''Double Matrix Board System'' and the details of the patent application for the device are included in the Appendices to the Thesis document. (author)

  1. Electrification of particulates in industrial and natural multiphase flows

    CERN Document Server

    Gu, Zhaolin

    2017-01-01

    This book introduces comprehensive fundamentals, numerical simulations and experimental methods of electrification of particulates entrained multiphase flows. The electrifications of two particulate forms, liquid droplets and solid particles, are firstly described together. Liquid droplets can be charged under preset or associated electric fields, while solid particles can be charged through contact. Different charging ways in gas (liquid)-liquid or gas-solid multiphase flows are summarized, including ones that are beneficial to industrial processes, such as electrostatic precipitation, electrostatic spraying, and electrostatic separation, etc., ones harmful for shipping and powder industry, and ones occurring in natural phenomenon, such as wind-blown sand and thunderstorm. This book offers theoretical references to the control and utilization of the charging or charged particulates in multiphase flows as well.

  2. Gaseous and particulate air pollutants in the Northeastern Mediterranean Coast

    International Nuclear Information System (INIS)

    Soner Erduran, M.; Tuncel, Semra G.

    2001-01-01

    The concentrations of sulfur dioxide (SO 2 ), ammonia (NH 3 ) and particulate matter were measured for a 6-month period and the concentration of gas phase nitric acid (HNO 3 ) was measured for a 1-month period in the North-eastern Mediterranean atmosphere (Kuecuek Calticak, Antalya) using a 'filter pack' system that was developed and optimised in our laboratory. Among all the gas phase pollutants, HNO 3 had the lowest concentration (0.42 μg m -3 ) followed by ammonia. Most of the measured parameters showed variation in time depending on strengths of source regions and meteorological conditions. Nitric acid is found mostly in particulate form, but gas to particulate partitioning of SO 2 shows seasonal variation. Wind trajectory analyses indicate that the major contribution to the observed concentrations come mostly from Eastern Europe and Blacksea regions as well as the southern sector

  3. Characterization of the particulate air pollution in contrasted mega cities

    International Nuclear Information System (INIS)

    Favez, O.

    2008-02-01

    This work aims at characterizing the physics and the chemistry that govern particulate air pollution in two mega cities (Paris and Cairo) for which the size distribution and the chemical composition of airborne particles were poorly documented. Seasonal variations of the main aerosol sources and transformation processes are investigated in these two urban centres, with a particular attention to semi-volatile material and secondary organic aerosols. Short-term health effects of Paris size-segregated aerosols, as well as particulate pollution during the Cairo 'Black Cloud' season, are also emphasized here. Finally, the comparison of results obtained for the two mega cities and for another one (Beijing) allows investigating main factors responsible for particulate air pollution in urban centres with contrasted climatic conditions and development levels. Notably, this work also allows the build-up of an experimental dataset which is now available for the modelling of urban air quality and of environmental impacts of mega city air pollution. (author)

  4. Samplings of urban particulate matter for mutagenicity assays

    International Nuclear Information System (INIS)

    De Zaiacono, T.

    1996-07-01

    In the frame of a specific program relating to the evaluation of mutagenic activity of urban particulate matter, an experimental arrangement has been developed to sample aerosuspended particles from the external environment carried indoor by means of a fan. Instrumentation was placed directly in the air flow to minimize particle losses, and consisted of total filter, collecting particles without any size separation; cascade impactor, fractioning urban particulate to obtain separate samples for analyses; an optical device, for real time monitoring of aerosol concentration, temperature and relative humidity sensors. Some of the samples obtained were analysed to investigate: particle morphology, aerosol granulometric distributions, effect of relative humidity on collected particulate, amount of ponderal mass compared with real time optical determinations. The results obtained are reported here, together with some considerations about carbonaceous particles, in urban areas mainly originated from diesel exhausts, their degree of agglomeration and role to vehiculate substances into the human respiratory

  5. Particulate and carbon monoxide emissions from small scale firewood combustion

    International Nuclear Information System (INIS)

    Todd, J.J.

    1990-01-01

    One of the serious adverse effects of residential firewood use is the deterioration in air quality caused by wood-smoke. Low combustion zone temperatures, flame quenching, poor gas mixing, and lack of oxygen all contribute to relatively high emissions of particulates and CO. Average emission rates for particulates of 11 g/h for modern woodheaters can certainly be improved upon. More research effort is needed to reduce emissions from cooking stoves used in developing countries and more public information on correct heater use is needed in the developed countries. (author)

  6. Particulate air pollution, with emphasis on traffic generated aerosols

    DEFF Research Database (Denmark)

    Fauser, Patrik

    constitute each about 5 wt-% of the collected suspended particulate matter in inner city air. The particle size distribution shows that 92 % of the mass of airborne particulate tire debris have aerodynamic diameters smaller than 1 µm. The mean aerodynamic diameter is about 1 µm for the bitumen particles...... % of this concentration derives from adsorbed particles on both leaf sides. The remainder is either respired through stomata or incorporated in the epicuticular wax layer. The fact that a substantial amount of the airborne tire and bitumen particles occur in the submicron range permits long range transportation...

  7. Role of oxidative damage in toxicity of particulates

    DEFF Research Database (Denmark)

    Møller, Peter; Jacobsen, Nicklas R; Folkmann, Janne K

    2010-01-01

    composition play important roles in the oxidative potential of particulates. Studies in animal models indicate that particles from combustion processes (generated by combustion of wood or diesel oil), silicate, titanium dioxide and nanoparticles (C60 fullerenes and carbon nanotubes) produce elevated levels......Particulates are small particles of solid or liquid suspended in liquid or air. In vitro studies show that particles generate reactive oxygen species, deplete endogenous antioxidants, alter mitochondrial function and produce oxidative damage to lipids and DNA. Surface area, reactivity and chemical...

  8. Distribution and seasonal variation of concentrations of particulate carbohydrates and uronic acids in the northern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B.; Fernandes, L.; Gopalakrishna, V.V.; Bhosle, N.B.; Fernandes, V.; Matondkar, S.G.P.; Bhushan, R.

    particulate carbohydrate (TPCHO), total particulate uronic acid (TPURA) and total particulate neutral carbohydrate (TPNCHO) concentrations and composition. Strong spatial, temporal and depth related variations were evident in the distribution...

  9. “La Constitución de los Pueblos de Occidente”. Une proposition inédite du voyageur cAlî Bey l’Abbasside pour le Maroc dans l´Arxiu Històric de la Ciutat de Barcelona (AHCB, Col. Toda, Ms B.162-II

    Directory of Open Access Journals (Sweden)

    Mercè Viladrich

    2006-11-01

    Full Text Available L’objectif de ce travail est de faire connaître et d’éditer à partir d’un manuscrit autographe le texte intitulé Constitution des peuples d´Occident rédigé par le voyageur catalan Domènec Badía i Leblich (1767-18181, connu sous le nom d’cAlî Bey l’Abbasside. Cette grande charte était destinée à s´implanter comme texte légal dans l´Empire du Maroc. Fonctionnaire au service du premier ministre de Carlos IV, Manuel de Godoy, Domènec Badía voyagea en 1803 au Maroc, dans la péninsule Arabique et au Moyen Orient et gagna une certaine célébrité parmi ses contemporains en racontant ses aventures dans un récit Les voyages d´Ali Bey en Asie et en Afrique, œuvre qui mélange vérité historique et fiction et dans laquelle l´auteur révèle une psychologie pathologique.

  10. Fonctions, défis et enjeux de la gestion et du développement durables dans la Réserve de Biosphère de l’Arganeraie (Maroc

    Directory of Open Access Journals (Sweden)

    Brahim El Fasskaoui

    2009-09-01

    Full Text Available  Le Maroc est l’un des rares pays d’Afrique du Nord à disposer d’un ensemble d’écosystèmes endémiques d’une biodiversité remarquable. Ces écosystèmes sont sérieusement menacés par l’expansion et le développement de certains secteurs comme le tourisme, l’agriculture et l’urbanisation. Conscient de l’importance de ces écosystèmes dans le développement durable, l’UNESCO a distingué certains d’entre eux par le Label du Patrimoine Mondial en leur donnant le statut de « Réserve de Biosphère ». Cette contribution tente d’examiner l’expérience marocaine en matière de politique des espaces protégés à partir de l’exemple de la Réserve de Biosphère de l’Arganeraie.Morocco is one of the few countries in North Africa to have a range of ecosystems endemic biodiversity remarkable. These ecosystems are seriously threatened by the expansion and development of certain sectors such as tourism, agriculture and urbanization. Recognizing the importance of these ecosystems in sustainable development, UNESCO has identified some of them by the World Heritage label by giving them the status of "Biosphere Reserve". This contribution attempts to examine the Moroccan experience in policy areas protected from the example of the Biosphere Reserve of Arganeraie.

  11. L’agriculture urbaine à Meknès (Maroc à la croisée des chemins : disparition d’une agriculture marginalisée ou retour de la cité jardin?

    Directory of Open Access Journals (Sweden)

    Patrick Dugué

    2015-10-01

    Full Text Available L’accroissement démographique rapide des villes au sud de la méditerranée s’est accompagné d’une urbanisation consommatrice de terres fertiles. Toutefois des espaces interstitiels difficilement constructibles, entre les espaces construits, hébergent encore des exploitations agricoles. C’est le cas notamment des 3 vallées traversant l’agglomération de Meknès, au Maroc. Sur la base d’enquêtes auprès de 80 agriculteurs et 42 consommateurs et d’entretiens avec des décideurs et commerçants de cette ville, nous avons montré la diversité des systèmes de production présents dans la ville (maraîchage et élevage laitier et à viande principalement. Malgré la proximité de la ville, peu de produits sont vendus directement aux consommateurs. Dans le cas du maraîchage, une action urgente est à engager pour fournir de l’eau d’irrigation de qualité aux agriculteurs de ces vallées afin qu’ils renoncent au détournement des eaux usées produites par la ville. Les meilleurs atouts de l’agriculture dans les villes au sud de la Méditerranée sont d’une part de rendre possible l’existence de paysages verdoyants et ouverts permettant d’améliorer le bien-être des citadins et l’attractivité touristique de ces villes et d’autre part l’intérêt récent de citadins pour des produits de qualité vendus en circuit court.

  12. Les partenariats entre les acteurs de tourisme pour la mise en place de durabilité, le cas de la région Marrakech Tensuft Alhaouz, au Maroc

    Directory of Open Access Journals (Sweden)

    Mohamed Hadach

    2015-09-01

    Full Text Available L’existence des partenariats entre les acteurs de tourisme est une condition sine qua non de succès des expériences de tourisme durable. D’abord les partenariats entre les acteurs privés et publics permettent la facilité de financement des infrastructures de qualité, nécessaires à la mise en place d’un tourisme qui respecte les exigences environnementales, économiques et socioculturelles, le partage des expériences et le savoir-faire des opérateurs internationaux. Ce travail a tenté de trouvé des raisonnements logiques de l’inadéquation entre l’offre et la demande en ce qui concerne les produits touristiques durables, à travers la mise en place d’une collaboration participative entre les différents acteurs de tourisme de la destination Marrakech au Maroc. En effet nous avons constaté que parmi les facteurs qui peuvent conduire à l’échec de toute forme de tourisme durable, le manque des études au préalable de la demande touristique en adéquation avec ce que les acteurs de tourisme peuvent proposer comme offre durable. Un conflit de temporalité entre la logique des acteurs publiques et celles des organismes privés de tourisme a été soulevé par plusieurs parties prenantes, de plus la nécessité de mettre en place une charte partenariale entre les acteurs de tourisme constitue un pilier pour la mise en place de la durabilité dans ce secteur.

  13. Sensitive determination of total particulate phosphorus and particulate inorganic phosphorus in seawater using liquid waveguide spectrophotometry.

    Science.gov (United States)

    Ehama, Makoto; Hashihama, Fuminori; Kinouchi, Shinko; Kanda, Jota; Saito, Hiroaki

    2016-06-01

    Determining the total particulate phosphorus (TPP) and particulate inorganic phosphorus (PIP) in oligotrophic oceanic water generally requires the filtration of a large amount of water sample. This paper describes methods that require small filtration volumes for determining the TPP and PIP concentrations. The methods were devised by validating or improving conventional sample processing and by applying highly sensitive liquid waveguide spectrophotometry to the measurements of oxidized or acid-extracted phosphate from TPP and PIP, respectively. The oxidation of TPP was performed by a chemical wet oxidation method using 3% potassium persulfate. The acid extraction of PIP was initially carried out based on the conventional extraction methodology, which requires 1M HCl, followed by the procedure for decreasing acidity. While the conventional procedure for acid removal requires a ten-fold dilution of the 1M HCl extract with purified water, the improved procedure proposed in this study uses 8M NaOH solution for neutralizing 1M HCl extract in order to reduce the dilution effect. An experiment for comparing the absorbances of the phosphate standard dissolved in 0.1M HCl and of that dissolved in a neutralized solution [1M HCl: 8M NaOH=8:1 (v:v)] exhibited a higher absorbance in the neutralized solution. This indicated that the improved procedure completely removed the acid effect, which reduces the sensitivity of the phosphate measurement. Application to an ultraoligotrophic water sample showed that the TPP concentration in a 1075mL-filtered sample was 8.4nM with a coefficient of variation (CV) of 4.3% and the PIP concentration in a 2300mL-filtered sample was 1.3nM with a CV of 6.1%. Based on the detection limit (3nM) of the sensitive phosphate measurement and the ambient TPP and PIP concentrations of the ultraoligotrophic water, the minimum filtration volumes required for the detection of TPP and PIP were estimated to be 15 and 52mL, respectively. Copyright © 2016

  14. Daily variability of suspended particulate concentrations and yields and their effect on river particulates chemistry

    Directory of Open Access Journals (Sweden)

    M. Meybeck

    2015-03-01

    Full Text Available Daily total suspended solids concentrations (TSS, mg L-1, yields (Y, kg day-1 km-2 and runoff (q, L s-1 km-2 in world rivers are described by the median (C50, the upper percentile (C99, the discharge-weighted average concentrations (C*, and by their corresponding yields (Y50, Y99, Y* and runoff (q*, q50, q99. These intra-station descriptors range over two to six orders of magnitude at a given station. Inter-station variability is considered through three sets of dimensionless metrics: (i q*/q50, C*/C50 and Y*/Y50, defining the general temporal variability indicators, and q99/q50, C99/C50 and Y99/Y50, defining the extreme variability indicators; (ii river flow duration (W2 and flux duration (M2 in 2% of time; and (iii the truncated rating curve exponent (b50sup of the C vs q relationship for the upper flows. The TSS and Y variability, measured on US, French and world rivers, are first explained by hydrological variability through the b50sup metric, the variability amplifier, then by basin size, erodibility, relief and lake occurrence. Yield variability is the product of runoff variability × TSS variability. All metrics are considerably modified after river damming. The control of river particulate matter (RPM composition by TSS or yields depends on the targeted component. For major elements (Al, Fe, Mn, Ti, Si, Ca, Mg, Na, K, the average RPM chemistry is not dependent on C* and Y* in most world hydroregions, except in the tropical hydrobelt where it is controlled by basin relief. By contrast, the particulate organic carbon content (POC, as a percentage of RPM is inversely correlated to TSS concentrations for (i intra-station measurements in any hydroregion, and (ii inter-station average POC and TSS figures in world rivers. TSS controls heavy metal content (ppm in highly contaminated basins (e.g. Cd in the Seine vs the Rhone, and total metal concentration (ng/L in all cases. Relations between RPM composition and TSS should be taken into account

  15. Controlling particulate matter under the Clean Air Act: a menu of options

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    This document was prepared by STAPPA and ALAPCO to help US state and local air pollution control officials understand the effects of particulate matter (PM) on human health and air quality, the relative contribution of various sources to particulate emissions, and the effectiveness and costs of various approaches - including innovative ones - to minimizing these emissions. The document covers particulate matter with a nominal diameter of 10 microns ({mu}m) or less (PM{sub 10}), including `fine` PM of 2.5 microns or less in diameter (PM{sub 2.5}). Sections cover: the effects of particulate matter on human health; regulatory issues; characterization of particulate matter; emission control strategies for mobile sources (diesel engines, small nonroad engines, alternative fuels etc.), particulates from stationary sources (electric utilities, industry and commercial fuel combustion; mineral products industry, metallurgical industry etc.); particulates from area sources; and market-based strategies for controlling particulate matter. 2 apps.

  16. Characteristics of Airborne Particulates Containing Naturally Occurring Radioactive Materials in Monazite Industry

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Geon; Choi, Cheol Kyu; Park, Il; Kim, Min Jun; Go, A Ra; Ji, Seung Woo; Kim, Kwang Pyo [Kyunghee University, Yongin (Korea, Republic of); Koo, Bon Cheol [KINS, Daejeon (Korea, Republic of)

    2016-05-15

    The objective of this study was to characterize physicochemical properties of airborne particulates at a monazite pulverization industry. The properties included particulate size distribution, concentration, shape, density, and radioactivity concentration. Monazite is one of the minerals containing naturally occurring radioactive material (NORM). Therefore, external and internal exposure can be occurred to the workers in monazite industry. The major exposure pathway of the workers is internal exposure due to inhalation of airborne particulates. According to International Commission on Radiological Protection (ICRP), radiation dose due to inhaled particulates containing NORM depends on particulate properties. Therefore, ICRP recommended the internal dose assessment using measured physicochemical properties of the airborne particulates. In the absence of specific information, ICRP provided default reference values. In this study, we characterized physicochemical properties of airborne particulates at a monazite pulverization industry. The databases of particulate information can be used for accurate internal dose assessment of worker.

  17. COPPER-DEPENDENT INFLAMMATION AND NUCLEAR FACTOR-KB ACTIVATION BY PARTICULATE AIR POLLUTION

    Science.gov (United States)

    Particulate air pollution causes increased cardiopulmonary morbidity and mortality, but the chemical determinants responsible for its biologic effects are not understood. We studied the effect of total suspended particulates collected in Provo, Utah, an area where an increase in ...

  18. The evaluation of a ceramic diesel particulate filter in an underground mine laboratory

    International Nuclear Information System (INIS)

    Carlson, D.H.; Bucheger, D.; Patton, M.; Johnson, J.H.

    1986-01-01

    This paper details the collection of diesel exhaust particulate from the instrumented Wagner ST5A load-haul-dump vehicle during a simulated ore loading and hauling operation. An evaluation of the exhaust included measurements to determine the effect of the Corning diesel particulate filter (DPF) on air quality, and the effect of operating variables and fuel additives on DPF regeneration. The results demonstrate the important effects of other mine particulate sources on the particulate collection efficiency

  19. Particulate Matter Filtration Design Considerations for Crewed Spacecraft Life Support Systems

    Science.gov (United States)

    Agui, Juan H.; Vijayakumar, R.; Perry, Jay L.

    2016-01-01

    Particulate matter filtration is a key component of crewed spacecraft cabin ventilation and life support system (LSS) architectures. The basic particulate matter filtration functional requirements as they relate to an exploration vehicle LSS architecture are presented. Particulate matter filtration concepts are reviewed and design considerations are discussed. A concept for a particulate matter filtration architecture suitable for exploration missions is presented. The conceptual architecture considers the results from developmental work and incorporates best practice design considerations.

  20. SOURCE SAMPLING FINE PARTICULATE MATTER: WOOD-FIRED INDUSTRIAL BOILER

    Science.gov (United States)

    The report provides a profile for a wood-fired industrial boiler equipped with a multistage electrostatic precipitator control device. Along with the profile of emissions of fine particulate matter of aerodynamic diameter of 2.5 micrometers or less (PM-2.5), data are also provide...

  1. Effect of Particulates Generated from Asphalt Production on the ...

    African Journals Online (AJOL)

    PROF HORSFALL

    in air, including dust, soot, dirt, smoke and liquid droplets. Particulate matter is of localized importance near roads, cement works, and other industrial areas. Apart from screening out sunlight, dust on leaf blocks stomata and lowers their conductants to Carbon iv oxide (Jitin and Manish, 2014). Asphalt, which is also referred ...

  2. Particulate matter characterization of Cauca River water in Colombia

    NARCIS (Netherlands)

    Gutierrez Marin, Juan Pablo; van Halem, D.; Rietveld, L.C.

    2016-01-01

    The particulate matter composition in the Upper Cauca River section was studied, considering the importance of this river for the water supply of Cali, Colombia, and the implications that the turbidity of this water source has had for the city's water treatment. Additionally, the upstream Palo River

  3. Diesel particulate emission in the South African mining industry.

    CSIR Research Space (South Africa)

    Van Niekerk, WCA

    2002-06-01

    Full Text Available measurements was confirmed by comparison of duplicate samples with analyses conducted by the Health and Safety Executive (HSE) in the UK. Furthermore, good agreement in readings was obtained between the Horiba instrument and the R&P direct-reading analyser... ......................................................................................................3 2.2 Characteristics and biological significance of particulates.................................................... 3 2.3 Animal studies...

  4. 40 CFR 86.145-82 - Calculations; particulate emissions.

    Science.gov (United States)

    2010-07-01

    ... = 0.43(Mp1 + Mp2)/(Dct + Ds) + 0.57(Mp3 + Mp2)/(Dht = Ds) where: (1) Mp1 = Mass of particulate... the cold start test, in miles. (6) Dht = The measured driving distance from the “transient” phase of...

  5. Deposition of Suspended Fine Particulate Matter in a Library

    Czech Academy of Sciences Publication Activity Database

    Smolík, Jiří; Mašková, Ludmila; Zíková, Naděžda; Ondráčková, Lucie; Ondráček, Jakub

    2013-01-01

    Roč. 1, 3 April (2013) ISSN 2050-7445 R&D Projects: GA MK DF11P01OVV020 Keywords : fine particulate matter * deposition * brownian diffusion Subject RIV: CF - Physical ; Theoretical Chemistry http://www.heritagesciencejournal.com/content/1/1/7

  6. Distribution spatiale intra-urbaine des particules fines : monitoring ...

    African Journals Online (AJOL)

    SARAH

    30 sept. 2014 ... En outre, l'accumulation des particules fines est faible pendant un mois pluvieux par rapport à un mois sec ..... benjamina, et la structure (tige, branches) des arborées ... par Zhang et al., (2006) sur des feuilles de Pinus pumila.

  7. Removal of residual particulate matter from filter media

    Science.gov (United States)

    Almlie, Jay C; Miller, Stanley J

    2014-11-11

    A method for removing residual filter cakes that remain adhered to a filter after typical particulate removal methodologies have been employed, such as pulse-jet filter element cleaning, for all cleanable filters used for air pollution control, dust control, or powder control.

  8. Nature of suspended particulate matter and concentrations of heavy ...

    African Journals Online (AJOL)

    The concentrations of metals in bottom sediment in the Tanzanian waters of Lake Victoria and the nature of suspended particulate matter (SPM) were analysed. The objective of the study was to compare levels of metals in sediment from different locations and to establish their sources. Metal concentrations were higher in ...

  9. Trace metals concentration assessment in urban particulate matter ...

    African Journals Online (AJOL)

    This study was conducted to investigate the distribution and correlation of selected trace elements (Ca, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in Yenagoa, Bayelsa State and its environs. Air particulate matter was collected gravimetrically at five stations (using a high volume portable SKC air check MTXSidekickair sampler ...

  10. Relationship between indoor and outdoor carbonaceous particulates in roadside households

    Energy Technology Data Exchange (ETDEWEB)

    Funasaka, K.; Miyazaki, T.; Tsuruho, K. [Osaka City Institute of Public Health and Environmental Sciences (Japan); Tamura, K. [The National Institute for Minamata Disease, Kumamoto (Japan); Mizuno, T. [Mie University (Japan). Dept. of Chemistry for Materials; Kuroda, K. [Osaka City University Medical School (Japan). Dept. of Preventive Medicine and Environmental Health

    2000-07-01

    Concentrations of particulate matter (PM) and carbonaceous particulates in indoor and outdoor air at roadside private households were measured in Osaka, Japan. The particulate samples were collected on filters using a portable AND sampler capable of separating particles into three different size ranges: over 10 {mu}m, 2-10 {mu}m (coarse) and below 2 {mu}m (fine) in aerodynamic diameter. The filters were weighed and then analyzed for elemental carbon (EC) and organic carbon (OC) by thermal oxidation using a CHN CORDER. The results showed that indoor fine PM concentration is considerably affected by fine EC and the fine EC in indoor air is significantly correlated to that in outdoor air, r = 0.86 (n = 30, p < 0.001). A simple estimation from EC content ratio in diesel exhaust particles indicated that about 30% of indoor particulates of less than 10 {mu}m (PM10) were contributed from diesel exhaust. Additionally, the size characteristics of outdoor PM at roadside and background sites were examined using Andersen Cascade Impactors. (author)

  11. Respiratory dose analysis for components of ambient particulate matter#

    Science.gov (United States)

    Particulate matter (PM) in the atmosphere is a complex mixture of particles with different sizes and chemical compositions. Although PM is known to cause health hazard, specific attributes of PM that may cause health effects are somewhat ambiguous. The dose of each specific compo...

  12. Characteristics, Causes, and Evaluation of Helicopter Particulate Visual Obstruction

    Science.gov (United States)

    2012-09-10

    future full-scale testing. The thrust sources examined were a 1 in. diameter nozzle , a 4 in. diameter nozzle , and a 16 in. ducted fan. The sources...Hiller also evaluated inclining the thrust vector , and determined there was little reduction in dynamic pressure at the point of ground interaction...CHARACTERISTICS, CAUSES, AND EVALUATION OF HELICOPTER PARTICULATE VISUAL OBSTRUCTION THESIS

  13. Membrane Characteristics for Removing Particulates in PFC Wastes

    International Nuclear Information System (INIS)

    Kim, Gye Nam; Lee, Sung Yeol; Won, Hui Jun; Jung, Chong Hun; Oh, Won Zin; Park, Jin Ho

    2005-01-01

    Pc (Per fluorocarbon) decontamination process is one of best methods to remove hot particulate adhered at inside surface of hot cell and surface of equipment in hot cell. It was necessary to develop a particulate filtration equipment to reuse Pc solution used on Pc decontamination due to its high cost and to minimize the volume of second wastewater. Contamination characteristics of hot particulate were investigated and then a filtration process was presented to remove hot particulate in Pc solution generated through Pc decontamination process. The removal efficiency of Pvdf (Poly vinylidene fluoride), Pp (Polypropylene), Ceramic (Al 2 O 3 ) filter showed more than 95%. The removal efficiency of Pvdf filter was a little lower than those of other kiters at same pressure (3 psi). A ceramic filter showed a higher removal efficiency with other filters, while a little lower flux rate than other filters. Due to inorganic composition, a ceramic filter was highly stable against radio nuclides in comparison with Pvdf and Pp membrane, which generate H 2 gas in α-radioactivity atmosphere. Therefore, the adoption of ceramic filter is estimated to be suitable for the real nitration process.

  14. Amino sugars in suspended particulate matter from the Bay

    Indian Academy of Sciences (India)

    particulate nitrogen (PN)and AS concentrations and composition.The AS varied between 0.4 and 17.5 nmol/l.Concentrations were high in the surface waters and generally decreased with increasing depth.AS concentration decreased from the south to ...

  15. Particulate matter urban air pollution from traffic car

    Science.gov (United States)

    Filip, G. M.; Brezoczki, V. M.

    2017-05-01

    The particulate matters (PM) are very important compounds of urban air pollution. There are a lot of air pollution sources who can generate PM and one of the most important of them it is urban traffic car. Air particulate matters have a major influence on human health so everywhere are looking for PM reducing solutions. It is knows that one of the solution for reduce the PM content from car traffic on ambient urban air is the fluidity of urban traffic car by introduction the roundabout intersections. This paper want to present some particulate matter determinations for PM10 and PM2.5 conducted on the two types of urban intersection respectively traffic light and roundabout intersections in Baia Mare town in the approximate the same work conditions. The determinations were carried out using a portable particulate matter monitor Haz - Dust model EPAM - 5000, who can provide a real time data for PM10, PM 2.5.Determinations put out that there are differences between the two locations regarding the PM content on ambient air. On roundabout intersection the PM content is less than traffic light intersection for both PM10 and PM 2.5 with more than 30%.

  16. Spatial Distribution of Suspended Particulate Matter in Mtwapa ...

    African Journals Online (AJOL)

    ... in the three sites; it accounts for a mean of 61% ±20 in Ramisi, 97% ±0.7 in Shirazi and 65% ±29 in Mtwapa. These high detritus levels are expected because of the allochthonous supply of particulate material by the river in Ramisi and the contribution from mangroves, which fringe the banks of the estuary and the creeks.

  17. Particulate Matter and Noise Impact Studies of Waste Rock Dump ...

    African Journals Online (AJOL)

    Adansi Gold Company Limited identified an economically viable gold deposit at Nkran in the Amansie West District of Ghana. Mining of this deposit requires the disposal of waste rock materials at a proposed waste rock dump near Nkran and Koninase communities. Since particulates and noise emissions from the ...

  18. Removal of residual particulate matter from filter media

    Energy Technology Data Exchange (ETDEWEB)

    Almlie, Jay C.; Miller, Stanley J.

    2018-01-09

    A method for removing residual filter cakes that remain adhered to a filter after typical particulate removal methodologies have been employed, such as pulse-jet filter element cleaning, for all cleanable filters used for air pollution control, dust control, or powder control.

  19. Ionization for reducing particulate matter emissions from poultry houses

    NARCIS (Netherlands)

    Cambra-López, M.; Winkel, A.; Harn, van J.; Ogink, N.W.M.; Aarnink, A.J.A.

    2009-01-01

    We evaluated the effect of ionization in reducing particulate and gaseous emissions in broiler houses and its effect on particle size distribution. Furthermore, we evaluated the performance of the tested ionization system and its influence on bird performance. The experiment was done during two

  20. An assessment of common atmospheric particulate matter sampling ...

    African Journals Online (AJOL)

    The method detection limit was also low (0.2 to 1 μg/L) for most metals, and 50% and less standard deviation to mean ratios were obtained for Ni and Pb. Key words: Toxic metals, inductively coupled plasma mass spectroscopy, scanning electron microscopy coupled with energy dispersive spectrometry, particulate matter, ...

  1. Determination of trace elements in urban airborne particulates (PM ...

    African Journals Online (AJOL)

    Assessment of the air quality in Newcastle upon Tyne, UK was performed by determining the trace element content in airborne particulates (PM10). Samples were collected over a 12 month period (March 2011 to April 2012) using two high volume air sampler provided with a PM10 size selective inlet. The concentrations of ...

  2. Characterization of biological particulate loads in metropolitan air

    Science.gov (United States)

    J. A. Snow; R. D. Schein; W. J. Moroz

    1977-01-01

    The atmospheric particulate load includes a wide range of naturally occurring particles of biological origin that serve as a reservoir of allergenic agents in respiratory disease. Improved knowledge of potential aeroallergens is needed by medical clinicians. Aims are to better characterize air spora, qualitatively and quantitatively, and determine daily (by hour)...

  3. An Application Of Receptor Modeling To Identify Airborne Particulate ...

    African Journals Online (AJOL)

    An Application Of Receptor Modeling To Identify Airborne Particulate Sources In Lagos, Nigeria. FS Olise, OK Owoade, HB Olaniyi. Abstract. There have been no clear demarcations between industrial and residential areas of Lagos with focus on industry as the major source. There is need to identify potential source types in ...

  4. DIII-D dust particulate characterization (June 1998 Vent)

    International Nuclear Information System (INIS)

    Carmack, W.J.

    1999-01-01

    Dust is a key component of fusion power device accident source term. Understanding the amount of dust expected in fusion power devices and its physical and chemical characteristics is needed to verify assumptions currently used in safety analyses. An important part of this safety research and development work is to characterize dust from existing experimental tokamaks. In this report, the authors present the collection, data analysis methods used, and the characterization of dust particulate collected from various locations inside the General Atomics DIII-D vacuum vessel following the June 1998 vent. The collected particulate was analyzed at the Idaho National Engineering and Environmental Laboratory (INEEL). Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Choice of collection technique is important because the sampling method used can bias the particle size distribution collected. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Seventeen samples were collected including plasma facing surfaces in lower, upper, and horizontal locations, surfaces behind floor tiles, surfaces behind divert or tiles, and surfaces behind ceiling tiles. The results of the analysis are presented

  5. Review Of Consultations For Children With Sickle Cell Disease CHR Kenitra Morocco

    Directory of Open Access Journals (Sweden)

    Mouden Samira

    2015-01-01

    Full Text Available Abstract Also called sickle cell anemia Sickle cell anemia is a genetic disease of autosomal recessive linked to abnormal structure of the hemoglobin which leads to the formation of hemoglobin S HbS. The descriptive and cross that we conducted at the pediatric ward of the regional hospital Gharb study Chrarda benihessen Knitra we were enjoying a work force of 164 children with sickle cell disease over a period of twenty four months from June 2010 to June 2012 . On average seven to eight 7-8 new cases per year. The majority of these children admitted to the exhibit acute complications that are typically associated either to a chronic hemolytic anemia vaso -occlusive crisis acute chest syndrome or severe infections which aims to identify factors likely to play a role in the occurrence of the sickle cell crises. This can cause severe functional consequences with renal lung bone etc.. In order to understand the problems and difficulties faced by sickle cell and their families in their daily lives we have established a protocol form of a questionnaire exploring various aspects related to eating habits and lifestyle of these children. and their families as well as family socioeconomic status and the context of environmental life The size of the control group study consists of 60 children aged 7-14 years. Clinical and analytical information is collected from records medical records and doctors during consultations of these patients. The results show that 71 of these children are from rural areas against 20 of children of urban origin while 9 live in suburban area however. The majority of parents have irregular income low educational attainment. 68 of these children use septic false in parallel they use well water in consumption and domestic use. Clinical examination and blood cell abnormalities formula revealed prevalence of 76 for fever cases painful crises severe recurrent and unpredictable also observed as well as acute chest syndrome pneumonia or pulmonary infarction a bone or joint necrosis unpredictable 43 for leukocytosis . As we noted the presence of diarrhea in this sample. In conclusion the present study showed an association between the frequency of sickle cell crises especially infectious presented by the children studied and the environmental quality of family life in which the child develops.

  6. Monitoring Particulate Matter with Commodity Hardware

    Science.gov (United States)

    Holstius, David

    Health effects attributed to outdoor fine particulate matter (PM 2.5) rank it among the risk factors with the highest health burdens in the world, annually accounting for over 3.2 million premature deaths and over 76 million lost disability-adjusted life years. Existing PM2.5 monitoring infrastructure cannot, however, be used to resolve variations in ambient PM2.5 concentrations with adequate spatial and temporal density, or with adequate coverage of human time-activity patterns, such that the needs of modern exposure science and control can be met. Small, inexpensive, and portable devices, relying on newly available off-the-shelf sensors, may facilitate the creation of PM2.5 datasets with improved resolution and coverage, especially if many such devices can be deployed concurrently with low system cost. Datasets generated with such technology could be used to overcome many important problems associated with exposure misclassification in air pollution epidemiology. Chapter 2 presents an epidemiological study of PM2.5 that used data from ambient monitoring stations in the Los Angeles basin to observe a decrease of 6.1 g (95% CI: 3.5, 8.7) in population mean birthweight following in utero exposure to the Southern California wildfires of 2003, but was otherwise limited by the sparsity of the empirical basis for exposure assessment. Chapter 3 demonstrates technical potential for remedying PM2.5 monitoring deficiencies, beginning with the generation of low-cost yet useful estimates of hourly and daily PM2.5 concentrations at a regulatory monitoring site. The context (an urban neighborhood proximate to a major goods-movement corridor) and the method (an off-the-shelf sensor costing approximately USD $10, combined with other low-cost, open-source, readily available hardware) were selected to have special significance among researchers and practitioners affiliated with contemporary communities of practice in public health and citizen science. As operationalized by

  7. Seasonal changes in suspended particulate component in Bombay High oil field (Arabian Sea)

    Digital Repository Service at National Institute of Oceanography (India)

    Bhat, K.L.; Verlecar, X.N.; Venkat, K.

    of phytoplankton biomass. Ratio of silicate and nitrate to phosphate was 16:16:1 for monsoon and postmonsoon periods. Annual values of particulate carbohydrates, particulate proteins and particulate lipids in surface waters ranged from 40 to 265 mu g l sup(-1), 21...

  8. Electrically heated particulate filter regeneration methods and systems for hybrid vehicles

    Science.gov (United States)

    Gonze, Eugene V.; Paratore, Jr., Michael J.

    2010-10-12

    A control system for controlling regeneration of a particulate filter for a hybrid vehicle is provided. The system generally includes a regeneration module that controls current to the particulate filter to initiate regeneration. An engine control module controls operation of an engine of the hybrid vehicle based on the control of the current to the particulate filter.

  9. A new technology for the reduction of particulate matter from diesel engines in ships

    NARCIS (Netherlands)

    Van Rens, G.L.M.A.

    2008-01-01

    In this thesis the focus is on the particulate matter reduction of ships, as ships contribute significantly to the particulate matter concentration in ambient air. Because the fuel of sea ships contains a lot of ash, the emitted particulate matter will also contain a lot of ash. In car and truck

  10. 30 CFR 7.89 - Test to determine the particulate index.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Test to determine the particulate index. 7.89... Use in Underground Coal Mines § 7.89 Test to determine the particulate index. The test shall be... measured and recorded at each test mode. (ii) The data required for use in the particulate index...

  11. The geocentric particulate distribution: Cometary, asteroidal, or space debris?

    Science.gov (United States)

    Mcdonnell, J. A. M.; Ratcliff, P. R.

    1992-01-01

    Definition of the Low Earth Orbit (LEO) particulate environment has been refined considerably with the analysis of data from NASA's Long Duration Exposure Facility (LDEF). Measurements of the impact rates from particulates ranging from sub-micron to millimetres in dimension and, especially, information on their directionality has permitted new scrunity of the sources of the particulates. Modelling of the dynamics of both bound (Earth orbital) and unbound (hyperbolic interplanetary) particulates intercepting LDEF's faces leads to the conclusion that the source is dominantly interplanetary for particle dimensions of greater than some 5 microns diameter; however the anisotropy below this dimension demands lower velocities and is compatible with an orbital component. Characteristics of the LDEF interplanetary component are compatible with familiar meteoroid sources and deep space measurements. Understanding of the orbital component which exceeds the interplanetary flux by a factor of 4 is less clear; although the very small particulates in orbit have been associated with space debris (Lawrance and Brownlee, 1986) this data conflicts with other measurements (McDonnell, Carey and Dixon, 1984) at the same epoch. By analysis of trajectories approaching the Earth and its atmosphere, we have shown that a significant contribution could be captured by aerocapture, i.e., atmospheric drag, from either asteroidal or cometary sources; such enhancement is unlikely however to provide the temporal and spatial fluctuations observed by the LDEF Interplanetary Dust Experiment (Mullholland et al. 1992). A further new mechanism is also examined, that of aerofragmentation capture, where an atmospheric grazing trajectory, which would not normally lead to capture, leads to fragmentation by thermal or mechanical shock; the microparticulates thus created can be injected in large numbers, but only into short-lifetime orbits. The concentration in one particular orbit plane, could explain the

  12. Comparison of high efficiency particulate filter testing methods

    International Nuclear Information System (INIS)

    1985-01-01

    High Efficiency Particulate Air (HEPA) filters are used for the removal of submicron size particulates from air streams. In nuclear industry they are used as an important engineering safeguard to prevent the release of air borne radioactive particulates to the environment. HEPA filters used in the nuclear industry should therefore be manufactured and operated under strict quality control. There are three levels of testing HEPA filters: i) testing of the filter media; ii) testing of the assembled filter including filter media and filter housing; and iii) on site testing of the complete filter installation before putting into operation and later for the purpose of periodic control. A co-ordinated research programme on particulate filter testing methods was taken up by the Agency and contracts were awarded to the Member Countries, Belgium, German Democratic Republic, India and Hungary. The investigations carried out by the participants of the present co-ordinated research programme include the results of the nowadays most frequently used HEPA filter testing methods both for filter medium test, rig test and in-situ test purposes. Most of the experiments were carried out at ambient temperature and humidity, but indications were given to extend the investigations to elevated temperature and humidity in the future for the purpose of testing the performance of HEPA filter under severe conditions. A major conclusion of the co-ordinated research programme was that it was not possible to recommend one method as a reference method for in situ testing of high efficiency particulate air filters. Most of the present conventional methods are adequate for current requirements. The reasons why no method is to be recommended were multiple, ranging from economical aspects, through incompatibility of materials to national regulations

  13. HUMAL ALVEOLAR MACROPHAGE RESPONSES TO AIR POLLUTION PARTICULATES ARE ASSOCIATED WITH INSOLUBLE OCMPONENTS OF COARSE MATERIAL, INCLUDING PARTICULATE ENDOTOXIN

    Science.gov (United States)

    Inhalation of particulate matter in the ambient air has been shown to cause pulmonary morbidity and exacerbate asthma. Alveolar macrophage (AM) are essential for effective removal of inhaled particles and microbes in the lower airways. While some particles minimally effect AM...

  14. Characteristics of thin and coarse particulates of urban and natural brazilian aerosols

    International Nuclear Information System (INIS)

    Orsini, C.Q.; Tabacnics, M.H.; Artaxo, P.; Andrade, M.F.; Kerr, A.S.

    1994-01-01

    Thin and coarse particulate were sampled during the period 1982-1985 in a natural coastal forest (Jureia), and five urban-industrial regions (Vitoria, Salvador, Porto Alegre, Sao Paulo and Belo Horizonte). The time variation of the concentration in the air, and the relative elementary composition of the thin and coarse particulate, sampled by thin and Coarse Particulate Sampler (AFG), were determined by gravimetric method and PIXE analysis respectively. The results demonstrated that the ground dust and salt from the sea are unequivocally one of the largest sources of coarse particulate, and also the ground is a significant thin particulate source. 25 refs, 22 figs, 28 tabs. (L.C.J.A.)

  15. Particulate filter behaviour of a Diesel engine fueled with biodiesel

    International Nuclear Information System (INIS)

    Buono, D.; Senatore, A.; Prati, M.V.

    2012-01-01

    Biodiesel is an alternative and renewable fuel made from plant and animal fat or cooked oil through a transesterification process to produce a short chain ester (generally methyl ester). Biodiesel fuels have been worldwide studied in Diesel engines and they were found to be compatible in blends with Diesel fuel to well operate in modern Common Rail engines. Also throughout the world the diffusion of biofuels is being promoted in order to reduce greenhouse gas emissions and the environmental impact of transport, and to increase security of supply. To meet the current exhaust emission regulations, after-treatment devices are necessary; in particular Diesel Particulate Filters (DPFs) are essential to reduce particulate emissions of Diesel engines. A critical requirement for the implementation of DPF on a modern Biodiesel powered engine is the determination of Break-even Temperature (BET) which is defined as the temperature at which particulate deposition on the filter is balanced by particulate oxidation on the filter. To fit within the exhaust temperature range of the exhaust line and to require a minimum of active regeneration during the engine running, the BET needs to occur at sufficiently low temperatures. In this paper, the results of an experimental campaign on a modern, electronic controlled fuel injection Diesel engine are shown. The engine was fuelled either with petroleum ultralow sulphur fuel or with Biodiesel: BET was evaluated for both fuels. Results show that on average, the BET is lower for biodiesel than for diesel fuel. The final goal was to characterize the regeneration process of the DPF device depending on the adopted fuel, taking into account the different combustion process and the different nature of the particulate matter. Overall the results suggest significant benefits for the use of biodiesel in engines equipped with DPFs. - Highlights: ► We compare Diesel Particulate Trap (DPF) performance with Biodiesel and Diesel fuel. ► The Break

  16. Particulate matter and health - from air to human lungs

    International Nuclear Information System (INIS)

    Piniero, T.; Cerqueira Alves, L.; Reis, M.

    1998-01-01

    The aim of this project is to search for respiratory system particular aggressors to which workers are submitted in their labouring activity. The work plan under the current IAEA contract comprise a prospective study to identify particulate matter deposited in the human respiratory ducts and lung tissue and workers respiratory health status survey at a steel plant, Siderurgia Nacional (SN). So far, the selection of areas of interest at SN, workers exposed, airborne particulate monitoring sites according to the periodicity of labouring cycles, and the beginning of workers medical survey have been achieved and/or initiated. The SN selected area, where steel is processed and steel casting is achieved, involve approximately 80 workers, most of them working at that location for more than 15 years. Blood elemental content data determined by PIXE and INAA and a preliminary health status evaluation from 32 of the 80 workers included in this survey are presented and discussed. (author)

  17. Recent developments in particulate control with low-rank fuels

    International Nuclear Information System (INIS)

    Miller, S.J.; Laudal, D.L.

    1991-01-01

    Regulations appear to be focusing on fine particle emissions rather than total mass particulate emissions. There is concern that electrostatic precipitators (ESPs) may not be able to meet potentially stricter finer particle emission standards. A new development in the area of fabric filtration is the use of flue gas-conditioning agents to reduce particulate emissions and pressure drop. Theoretical analysis of the factors that control the size of a baghouse indicates that pulse-jet baghouses can be designed to operate at much higher air-to-cloth ratios than is currently employed. To help optimize performance of both ESPs and baghouses, quantitative characterization of the cohesive properties of fly ash is necessary. Appropriate methods are determination of aerated and packed porosity and measurement of tensile strength as a function of porosity

  18. Les Particules élémentaires: Self–portrait

    Directory of Open Access Journals (Sweden)

    Gerald Prince

    2012-01-01

    Full Text Available Perhaps no French novel in the past fifteen years has received more critical attention than Michel Houellebecq’s Les Particules élémentaires and perhaps none has evoked stronger reactions with regard to the (literary values it espouses and represents. This (self-portrait, like any portrait, accents certain features more than others. It concentrates on refuting charges of nihilism, reactionaryism, sexism, and racism; it stresses Houellebecq’s novel’s attention to form and its thematic clarity as well as its determination to say something rather than nothing; and, through a consideration of its references to various media, arts, and texts, of its pet peeves and true delights, it specifies the nature and ambition of Les Particules élémentaires , the kind of text it is or aspires to be.

  19. Biological mechanisms and translocation kinetics of particulate plutonium

    International Nuclear Information System (INIS)

    Bruenger, F.W.; Stevens, W.; Atherton, D.R.; Roswell, R.L.; Smith, J.M.

    1981-01-01

    The dissolution and elimination of particulate 239 Pu from its initial sites of deposition in phagocytic organs (the liver, spleen, and lung), as well as its translocation and redeposition in soft tissue organs and skeleton have been investigated. Beagles were injected intravenously with particulate Pu and sacrificed sequentially at times ranging from 33 to 830 days after injection. Equations that describe the overall retention of Pu in liver, spleen, lung, and bone were calculated. Plutonium mobilized from these organs either re-entered the blood stream and redeposited in the skeleton and liver parenchyma or was excreted. The protracted translocation of Pu to bone surfaces potentially exposes all cells involved in osteogenesis to continuous α-radiation, a situation that could enhance the hazard of developing osteosarcoma. A kinetic model that describes the translocation of Pu from the phagocytic compartments to blood and its subsequent redistribution to bone, liver, and other organs was formulated

  20. High diversity of fungi in air particulate matter.

    Science.gov (United States)

    Fröhlich-Nowoisky, Janine; Pickersgill, Daniel A; Després, Viviane R; Pöschl, Ulrich

    2009-08-04

    Fungal spores can account for large proportions of air particulate matter, and they may potentially influence the hydrological cycle and climate as nuclei for water droplets and ice crystals in clouds, fog, and precipitation. Moreover, some fungi are major pathogens and allergens. The diversity of airborne fungi is, however, not well-known. By DNA analysis we found pronounced differences in the relative abundance and seasonal cycles of various groups of fungi in coarse and fine particulate matter, with more plant pathogens in the coarse fraction and more human pathogens and allergens in the respirable fine particle fraction (<3 microm). Moreover, the ratio of Basidiomycota to Ascomycota was found to be much higher than previously assumed, which might also apply to the biosphere.

  1. Bioengineering towards self-assembly of particulate vaccines.

    Science.gov (United States)

    Rehm, Bernd H A

    2017-12-01

    There is an unmet demand for safe and efficient vaccines for prevention of various infectious diseases. Subunit vaccines comprise selected pathogen specific antigens are a safe alternative to whole organism vaccines. However they often lack immunogenicity. Natural and synthetic self-assembling polymers and proteins will be reviewed in view their use to encapsulate and/or display antigens to serve as immunogenic antigen carriers for induction of protective immunity. Recent advances made in in vivo assembly of antigen-displaying polyester inclusions will be a focus. Particulate vaccines are inherently immunogenic due to enhanced uptake by antigen presenting cells which process antigens mediating adaptive immune responses. Bioengineering approaches enable the design of tailor-made particulate vaccines to fine tune immune responses towards protective immunity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Rechargeable particulate filter for radioactive contaminated gas streams

    International Nuclear Information System (INIS)

    Bonn, J.W.

    1976-01-01

    A system is disclosed which includes a closed housing having a plurality of rectangularly configured beds with perforated sidewalls longitudinally disposed in housing in laterally spaced disposition with each other. Alternate spaces at inlet end are closed and alternate spaces opposite the open ends are closed at exit end whereby contaminated gas is laterally squeezed through the beds filled with particulate adsorbent. The lower portions of the beds funnel into longitudinally extending discharge chutes enclosed within respective wells, the lower edges of the chutes rising at a constant angle above the well floor. An evacuation system coupled to the wells suctions the pile of particulate from the most remote portion of the chutes first. 3 claims, 7 drawing figures

  3. High efficiency particulate removal with sintered metal filters

    International Nuclear Information System (INIS)

    Kirstein, B.E.; Paplawsky, W.J.; Pence, D.T.; Hedahl, T.G.

    1981-01-01

    Because of their particle removal efficiencies and durability, sintered metal filters have been chosen for high efficiency particulate air (HEPA) filter protection in the off-gas treatment system for the proposed Idaho National Engineering Laboratory Transuranic Waste Treatment Facility. Process evaluation of sintered metal filters indicated a lack of sufficient process design data to ensure trouble-free operation. Subsequence pilot scale testing was performed with flyash as the test particulate. The test results showed that the sintered metal filters can have an efficiency greater than 0.9999999 for the specific test conditions used. Stable pressure drop characteristics were observed in pulsed and reversed flow blowback modes of operation. Over 4900 hours of operation were obtained with operating conditions ranging up to approximately 90 0 C and 24 vol % water vapor in the gas stream

  4. Gaseous and particulate emissions from a DC arc melter.

    Science.gov (United States)

    Overcamp, Thomas J; Speer, Matthew P; Griner, Stewart J; Cash, Douglas M

    2003-01-01

    Tests treating soils contaminated with metal compounds and radionuclide surrogates were conducted in a DC arc melter. The soil melted, and glassy or ceramic waste forms with a separate metal phase were produced. Tests were run in the melter plenum with either air or N2 purge gases. In addition to nitrogen, the primary emissions of gases were CO2, CO, oxygen, methane, and oxides of nitrogen (NO(x)). Although the gas flow through the melter was low, the particulate concentrations ranged from 32 to 145 g/m3. Cerium, a nonradioactive surrogate for plutonium and uranium, was not enriched in the particulate matter (PM). The PM was enriched in cesium and highly enriched in lead.

  5. Scavenging of particulate elemental carbon into stratus cloud

    Energy Technology Data Exchange (ETDEWEB)

    Kaneyasu, Naoki; Maeda, Takahisa [National Inst. for Resources and Environment, Tsukuba (Japan)

    1995-12-31

    The role of atmospheric aerosols on the alternation of cloud radiative properties has widely been recognized since 1977 when Tomey and his coworkers have numerically demonstrated the effect of increased cloud condensation nuclei (CCN). At the same time, cloud processes are one of the most important factor in controlling the residence time of atmospheric aerosols through the wet removal process. The redistribution of the size and the composition of pre-cloud aerosols is also the important role of cloud process on the nature of atmospheric aerosols. In order to study these cloud-aerosol interaction phenomena, the incorporation of aerosols into cloud droplets is the first mechanism to be investigated. Among the several mechanisms for the incorporation of aerosols into cloud droplets, nucleation scavenging, is the potentially important process in the view of cloud-aerosol interactions. This critical supersaturation for a given radius of a particle can be theoretically calculated only for pure species, e.g., NaCl. However, a significant portion of the atmospheric aerosols is in the form of internal mixture of multiple components, such as SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, NH{sub 4}{sup +} and particulate elemental carbon. The knowledge acquired by field measurements is therefore essential on this subject. The present study focuses on the scavenging of major components of urban atmospheric aerosols, in particular the incorporation of particulate elemental carbon into stratus cloud. Particulate elemental carbon is the strongest light absorbing species in visible region, and has potential to change the optical property of cloud. On the basis of the measurements conducted at a mountain located in the suburb of Tokyo Metropolitan area, Japan, some insights on the scavenging of particulate elemental carbon into cloud droplet will be presented

  6. MERCURY CONTROL WITH THE ADVANCED HYBRID PARTICULATE COLLECTOR

    International Nuclear Information System (INIS)

    Ye Zhuang; Stanley J. Miller; Grant E. Dunham; Michelle R. Olderbak

    2002-01-01

    Since 1995, DOE has supported development of a new concept in particulate control, called the advanced hybrid particulate collector (AHPC). The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas-solid contactor. The objective of the three-task project is to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach includes bench-scale batch testing that ties the new work to previous results and links results with larger-scale pilot testing with real flue gas on a coal-fired combustion system, pilot-scale testing on a coal-fired combustion system with both a pulse-jet baghouse and an AHPC to prove or disprove the research hypotheses, and field demonstration pilot-scale testing at a utility power plant to prove scaleup and demonstrate longer-term mercury control. This project, if successful, will demonstrate at the pilot-scale level a technology that would provide a cost-effective technique to accomplish control of mercury emissions and, at the same time, greatly enhance fine particulate collection efficiency. The technology can be used to retrofit systems currently employing inefficient ESP technology as well as for new construction, thereby providing a solution to a large segment of the U.S. utility industry as well as other industries requiring mercury control

  7. Ultrastructural immunocytochemistry of particulate fractions using polyvinyl chloride microculture wells.

    Science.gov (United States)

    Wray, B E; Sealock, R

    1984-10-01

    A method is described for immunoelectron microscopy of particulate subcellular fractions using polyvinyl chloride (soft) microculture wells as mechanical supports and reaction vessels. Appropriate quantities of particles are centrifuged onto the well bottoms, fixed and permeabilized if necessary, then labeled by standard procedures, fixed in glutaraldehyde and tannic acid, and prepared for thin section electron microscopy. The centrifugation, the fixations, and the embedment in Epon are discussed in detail.

  8. Removal of both dissolved and particulate iron from groundwater

    OpenAIRE

    H. van Dijk; H. Leijssen; L. Rietveld; A. Abrahamse; K. Teunissen

    2008-01-01

    Iron is the primary source for discolouration problems in the drinking water distribution system. The removal of iron from groundwater is a common treatment step in the production of drinking water. Even when clear water meets the drinking water standards, the water quality in the distribution system can deteriorate due to settling of iron (hydroxide) particles or post-treatment flocculation of dissolved iron. Therefore it is important to remove dissolved and particulate iron to a large exten...

  9. Characterization of Urban Runoff Pollution between Dissolved and Particulate Phases

    OpenAIRE

    Wei, Zhang; Simin, Li; Fengbing, Tang

    2013-01-01

    To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC) of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitr...

  10. Chemical and biological characterization of urban particulate matter

    International Nuclear Information System (INIS)

    Agurell, E.; Alsberg, T.; Assefaz-Redda, Y.

    1990-11-01

    Airborne particulate matter has been collected on glass fiber filter by high volume sampling in the Goeteborg urban area. The samples were, after extraction with respect to organic components, tested for biological effect in the Salmonella mutagenicity assay, affinity to the cytosol TCDD receptor and toxicity towards a mammalian cell system and analysed chemically for selected polycyclic aromatic compounds. A series of samples collected simultaneously at a street level location and a rooftop site showed that most parameters associated with the organic compounds adsorbed to airborne particulate matter has similar concentrations at the two levels. The differences observed for the mutagenic effect in different strains and conditions showed that the rooftop samples had a different composition compared to the street samples indicating that atmospheric transformations have occurred. Chemical fractionation of representative samples showed that the distribution of mutagenic activity among different fractions is dissimilar to the distribution obtained in the fractionation of both gasoline and diesel engine exhaust particles. Partial least squares regression analysis showed qualitatively that diesel exhaust is a major source of airborne particulate mutagenic activity and source apportionment with chemical mass balance and multilinear regression corroborated this quantitatively. The multilinear regression analysis gave the result that the airborne activity in Salmonella TA90-S9 originated to 54±4% from diesel exhaust and to 26±3% from gasoline exhaust. The contribution is more equal for the activity measured with TA98+S9. The usefulness of short-term bioassays as an addition to chemical analysis of airborne particulate matter depends on whether only polycylic aromatic hydrocarbons (PAH) are major carcinogens, as has been suggested in the literature, or whether also other polycyclic aromatic compound (PAC) are of importance. (au)

  11. Scavenging of particulate elemental carbon into stratus cloud

    Energy Technology Data Exchange (ETDEWEB)

    Kaneyasu, Naoki; Maeda, Takahisa [National Inst. for Resources and Environment, Tsukuba (Japan)

    1996-12-31

    The role of atmospheric aerosols on the alternation of cloud radiative properties has widely been recognized since 1977 when Tomey and his coworkers have numerically demonstrated the effect of increased cloud condensation nuclei (CCN). At the same time, cloud processes are one of the most important factor in controlling the residence time of atmospheric aerosols through the wet removal process. The redistribution of the size and the composition of pre-cloud aerosols is also the important role of cloud process on the nature of atmospheric aerosols. In order to study these cloud-aerosol interaction phenomena, the incorporation of aerosols into cloud droplets is the first mechanism to be investigated. Among the several mechanisms for the incorporation of aerosols into cloud droplets, nucleation scavenging, is the potentially important process in the view of cloud-aerosol interactions. This critical supersaturation for a given radius of a particle can be theoretically calculated only for pure species, e.g., NaCl. However, a significant portion of the atmospheric aerosols is in the form of internal mixture of multiple components, such as SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, NH{sub 4}{sup +} and particulate elemental carbon. The knowledge acquired by field measurements is therefore essential on this subject. The present study focuses on the scavenging of major components of urban atmospheric aerosols, in particular the incorporation of particulate elemental carbon into stratus cloud. Particulate elemental carbon is the strongest light absorbing species in visible region, and has potential to change the optical property of cloud. On the basis of the measurements conducted at a mountain located in the suburb of Tokyo Metropolitan area, Japan, some insights on the scavenging of particulate elemental carbon into cloud droplet will be presented

  12. The UK market for dust and particulate removal equipment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-08-01

    The report has a market overview of dust and particulate removal equipment, 1995-1999 and has specific market reports, by value, of fabric, ceramic and sintered filters, electrostatic precipitators, wet scrubbers (venturi, plate and others) and cyclones. It gives environmental expenditure by UK industry and discusses factors affecting supply, demand and success in the market. An overview is given of the industry structure and profiles are presented of 15 companies. Lists of contracts, trade associations and relevant journals are included. 33 tabs.

  13. Stabilization void-fill encapsulation high-efficiency particulate filters

    International Nuclear Information System (INIS)

    Alexander, R.G.; Stewart, W.E.; Phillips, S.J.; Serkowski, M.M.; England, J.L.; Boynton, H.C.

    1994-05-01

    This report discusses high-efficiency particulate air (HEPA) filter systems that which are contaminated with radionuclides are part of the nuclear fuel processing systems conducted by the US Department of Energy (DOE) and require replacement and safe and efficient disposal for plant safety. Two K-3 HEPA filters were removed from service, placed burial boxes, buried, and safely and efficiently stabilized remotely which reduced radiation exposure to personnel and the environment

  14. Source apportionment of airborne particulates through receptor modeling: Indian scenario

    Science.gov (United States)

    Banerjee, Tirthankar; Murari, Vishnu; Kumar, Manish; Raju, M. P.

    2015-10-01

    Airborne particulate chemistry mostly governed by associated sources and apportionment of specific sources is extremely essential to delineate explicit control strategies. The present submission initially deals with the publications (1980s-2010s) of Indian origin which report regional heterogeneities of particulate concentrations with reference to associated species. Such meta-analyses clearly indicate the presence of reservoir of both primary and secondary aerosols in different geographical regions. Further, identification of specific signatory molecules for individual source category was also evaluated in terms of their scientific merit and repeatability. Source signatures mostly resemble international profile while, in selected cases lack appropriateness. In India, source apportionment (SA) of airborne particulates was initiated way back in 1985 through factor analysis, however, principal component analysis (PCA) shares a major proportion of applications (34%) followed by enrichment factor (EF, 27%), chemical mass balance (CMB, 15%) and positive matrix factorization (PMF, 9%). Mainstream SA analyses identify earth crust and road dust resuspensions (traced by Al, Ca, Fe, Na and Mg) as a principal source (6-73%) followed by vehicular emissions (traced by Fe, Cu, Pb, Cr, Ni, Mn, Ba and Zn; 5-65%), industrial emissions (traced by Co, Cr, Zn, V, Ni, Mn, Cd; 0-60%), fuel combustion (traced by K, NH4+, SO4-, As, Te, S, Mn; 4-42%), marine aerosols (traced by Na, Mg, K; 0-15%) and biomass/refuse burning (traced by Cd, V, K, Cr, As, TC, Na, K, NH4+, NO3-, OC; 1-42%). In most of the cases, temporal variations of individual source contribution for a specific geographic region exhibit radical heterogeneity possibly due to unscientific orientation of individual tracers for specific source and well exaggerated by methodological weakness, inappropriate sample size, implications of secondary aerosols and inadequate emission inventories. Conclusively, a number of challenging

  15. Transport phenomena and drying of solids and particulate materials

    CERN Document Server

    Lima, AG

    2014-01-01

    The purpose of this book, Transport Phenomena and Drying of Solids and Particulate Materials, is to provide a collection of recent contributions in the field of heat and mass transfer, transport phenomena, drying and wetting of solids and particulate materials. The main benefit of the book is that it discusses some of the most important topics related to the heat and mass transfer in solids and particulate materials. It includes a set of new developments in the field of basic and applied research work on the physical and chemical aspects of heat and mass transfer phenomena, drying and wetting processes, namely, innovations and trends in drying science and technology, drying mechanism and theory, equipment, advanced modelling, complex simulation and experimentation. At the same time, these topics will be going to the encounter of a variety of scientific and engineering disciplines. The book is divided in several chapters that intend to be a resume of the current state of knowledge for benefit of professional c...

  16. Validation of NAA Method for Urban Particulate Matter

    International Nuclear Information System (INIS)

    Woro Yatu Niken Syahfitri; Muhayatun; Diah Dwiana Lestiani; Natalia Adventini

    2009-01-01

    Nuclear analytical techniques have been applied in many countries for determination of environmental pollutant. Method of NAA (neutron activation analysis) representing one of nuclear analytical technique of that has low detection limits, high specificity, high precision, and accuracy for large majority of naturally occurring elements, and ability of non-destructive and simultaneous determination of multi-elemental, and can handle small sample size (< 1 mg). To ensure quality and reliability of the method, validation are needed to be done. A standard reference material, SRM NIST 1648 Urban Particulate Matter, has been used to validate NAA method. Accuracy and precision test were used as validation parameters. Particulate matter were validated for 18 elements: Ti, I, V, Br, Mn, Na, K, Cl, Cu, Al, As, Fe, Co, Zn, Ag, La, Cr, and Sm,. The result showed that the percent relative standard deviation of the measured elemental concentrations are found to be within ranged from 2 to 14,8% for most of the elements analyzed whereas Hor rat value in range 0,3-1,3. Accuracy test results showed that relative bias ranged from -11,1 to 3,6%. Based on validation results, it can be stated that NAA method is reliable for characterization particulate matter and other similar matrix samples to support air quality monitoring. (author)

  17. Controlling exposure to DPM : diesel particulate filters vs. biodiesel

    International Nuclear Information System (INIS)

    Bugarski, A.D.; Shi, X.C.

    2009-01-01

    In order to comply with Mine Safety and Health Administration regulations, mining companies are required to reduce miners exposures to diesel particulate matter (DPM) to 160 μg/m 3 of total carbon. Diesel particulate filter (DPF) systems, disposable filter elements (DFEs), and diesel oxidation catalysts (DOCs) are among the most effective strategies and technologies for curtailing DPM at its source. Substituting diesel fuel with biodiesel blends is also considered to be a plausible solution by many underground mine operators. Studies were conducted at the National Institute for Occupational Safety and Health Diesel Laboratory at Lake Lynn Experimental Mine to evaluate various control technologies and strategies available to the underground mining industry to reduce exposure to DPM. The physical, chemical and toxicological properties of diesel aerosols (DPM) emitted by engines in an underground mine were also evaluated. The DPF and DFE systems were found to be highly effective in reducing total particulate and elemental carbon mass concentrations, total aerosol surface concentrations and, in most cases, concentrations of diesel aerosols in occupational settings such as underground mines. Soy methyl ester (SME) biodiesel fuels had the potential to reduce the mine air concentrations of total DPM, although the rate of reduction varied depending on engine operating conditions. The disadvantage of using biodiesel fuels was an increase in the fraction of particle-bound volatile organics and concentration of aerosols for light-load engine operating conditions.

  18. Particulate air pollution and daily mortality in Detroit.

    Science.gov (United States)

    Schwartz, J

    1991-12-01

    Particulate air pollution has been associated with increased mortality during episodes of high pollution concentrations. The relationship at lower concentrations has been more controversial, as has the relative role of particles and sulfur dioxide. Replication has been difficult because suspended particle concentrations are usually measured only every sixth day in the U.S. This study used concurrent measurements of total suspended particulates (TSP) and airport visibility from every sixth day sampling for 10 years to fit a predictive model for TSP. Predicted daily TSP concentrations were then correlated with daily mortality counts in Poisson regression models controlling for season, weather, time trends, overdispersion, and serial correlation. A significant correlation (P less than 0.0001) was found between predicted TSP and daily mortality. This correlation was independent of sulfur dioxide, but not vice versa. The magnitude of the effect was very similar to results recently reported from Steubenville, Ohio (using actual TSP measurements), with each 100 micrograms/m3 increase in TSP resulting in a 6% increase in mortality. Graphical analysis indicated a dose-response relationship with no evidence of a threshold down to concentrations below half of the National Ambient Air Quality Standards for particulate matter.

  19. Subsurface migration of radioactive waste materials by particulate transport

    International Nuclear Information System (INIS)

    Eichholz, G.G.; Craft, T.F.; Powell, G.F.; Wahlig, B.G.

    1982-01-01

    The role of suspended particles as carriers of dissolved nuclides from high-level radioactive waste repositories has been investigated. Depending on the concentrations of suspended particles and the nature of the invading water, it has been found that cationic nuclides may be competitively adsorbed on suspended clay particles, the partitioning being largely determined by pH, temperature, and comparative surface areas of particulates and surrounding rocks. Column tests with activated particles have been conducted and showed that the clay particles pass readily through porous mineral columns and are increasingly retained if salinity is increased. Retention in basalt columns is stronger in the presence of high concentrations of sodium and calcium ions and has been explained in terms of van der Waals forces. The range of particulate migration then depends on the condition of the rock surfaces, the persistence of a clay coating, and the total dissolved ion concentration. For adsorbable waste ions, this may represent a pathway comparable in significance to ion-exchange-controlled migration. For some bed materials, the particulate movement displayed a prompt and a delayed component; the nature of the delay mechanism is not fully understood at present

  20. Filtration of Carbon Particulate Emissions from a Plasma Pyrolysis Assembly

    Science.gov (United States)

    Agui, Juan H.; Green, Robert; Vijayakumar, R.; Berger, Gordon; Greenwood, Zach; Abney, Morgan; Peterson, Elspeth

    2016-01-01

    NASA is investigating plasma pyrolysis as a candidate technology that will enable the recovery of hydrogen from the methane produced by the ISS Sabatier Reactor. The Plasma Pyrolysis Assembly (PPA) is the current prototype of this technology which converts the methane product from the Carbon Dioxide Reduction Assembly (CRA) to acetylene and hydrogen with 90% or greater conversion efficiency. A small amount of solid carbon particulates are generated as a side product and must be filtered before the acetylene is removed and the hydrogen-rich gas stream is recycled back to the CRA. We discuss developmental work on several options for filtering out the carbon particulate emissions from the PPA exit gas stream. The filtration technologies and concepts investigated range from fibrous media to monolithic ceramic and sintered metal media. This paper describes the different developed filter prototypes and characterizes their performance from integrated testing at the Environmental Chamber (E-Chamber) at MSFC. In addition, characterization data on the generated carbon particulates, that help to define filter requirements, are also presented.

  1. An overview of particulate emissions from residential biomass combustion

    Science.gov (United States)

    Vicente, E. D.; Alves, C. A.

    2018-01-01

    Residential biomass burning has been pointed out as one of the largest sources of fine particles in the global troposphere with serious impacts on air quality, climate and human health. Quantitative estimations of the contribution of this source to the atmospheric particulate matter levels are hard to obtain, because emission factors vary greatly with wood type, combustion equipment and operating conditions. Updated information should improve not only regional and global biomass burning emission inventories, but also the input for atmospheric models. In this work, an extensive tabulation of particulate matter emission factors obtained worldwide is presented and critically evaluated. Existing quantifications and the suitability of specific organic markers to assign the input of residential biomass combustion to the ambient carbonaceous aerosol are also discussed. Based on these organic markers or other tracers, estimates of the contribution of this sector to observed particulate levels by receptor models for different regions around the world are compiled. Key areas requiring future research are highlighted and briefly discussed.

  2. Modelisation des emissions de particules microniques et nanometriques en usinage

    Science.gov (United States)

    Khettabi, Riad

    La mise en forme des pieces par usinage emet des particules, de tailles microscopiques et nanometriques, qui peuvent etre dangereuses pour la sante. Le but de ce travail est d'etudier les emissions de ces particules pour fins de prevention et reduction a la source. L'approche retenue est experimentale et theorique, aux deux echelles microscopique et macroscopique. Le travail commence par des essais permettant de determiner les influences du materiau, de l'outil et des parametres d'usinage sur les emissions de particules. E nsuite un nouveau parametre caracterisant les emissions, nomme Dust unit , est developpe et un modele predictif est propose. Ce modele est base sur une nouvelle theorie hybride qui integre les approches energetiques, tribologiques et deformation plastique, et inclut la geometrie de l'outil, les proprietes du materiau, les conditions de coupe et la segmentation des copeaux. Il ete valide au tournage sur quatre materiaux: A16061-T6, AISI1018, AISI4140 et fonte grise.

  3. Hyperspectral imaging applied to complex particulate solids systems

    Science.gov (United States)

    Bonifazi, Giuseppe; Serranti, Silvia

    2008-04-01

    HyperSpectral Imaging (HSI) is based on the utilization of an integrated hardware and software (HW&SW) platform embedding conventional imaging and spectroscopy to attain both spatial and spectral information from an object. Although HSI was originally developed for remote sensing, it has recently emerged as a powerful process analytical tool, for non-destructive analysis, in many research and industrial sectors. The possibility to apply on-line HSI based techniques in order to identify and quantify specific particulate solid systems characteristics is presented and critically evaluated. The originally developed HSI based logics can be profitably applied in order to develop fast, reliable and lowcost strategies for: i) quality control of particulate products that must comply with specific chemical, physical and biological constraints, ii) performance evaluation of manufacturing strategies related to processing chains and/or realtime tuning of operative variables and iii) classification-sorting actions addressed to recognize and separate different particulate solid products. Case studies, related to recent advances in the application of HSI to different industrial sectors, as agriculture, food, pharmaceuticals, solid waste handling and recycling, etc. and addressed to specific goals as contaminant detection, defect identification, constituent analysis and quality evaluation are described, according to authors' originally developed application.

  4. La filière d’oignon d’été dans le Saïs au Maroc : la place et le rôle des intermédiaires de la commercialisation

    Directory of Open Access Journals (Sweden)

    Caroline Lejars

    2014-11-01

    Full Text Available Les agriculteurs dépendent souvent, pour la commercialisation de leur produit, d'un réseau complexe d'intermédiaires privés. Dans les pays en développement, ces intermédiaires de la vente sont souvent accusés de réaliser des profits excessifs et d’être responsables des énormes écarts entre le prix de vente au champ et le prix payé par le consommateur. En s’appuyant sur l’étude de la filière oignon d’été dans le Saïs au Maroc, cet article analyse le rôle de ces réseaux d'intermédiaires, et la répartition des coûts et de la marge bénéficiaire le long de la chaine de production et de commercialisation. On montre ainsi que cette filière crée un grand nombre d'emplois en aval de la production, que ce soit pour la collecte, le stockage, le transport ou la vente. La part de la marge bénéficiaire revenant à l’ensemble des intermédiaires est supérieure à celle revenant aux producteurs, ce qui entraine effectivement une importante différence de prix entre le prix de vente et le prix du marché. Même si les profits et les rôles des intermédiaires sont très variables, certains des acteurs intermédiaires, notamment les détaillants et les revendeurs en gros, récupèrent des marges bien supérieures à celles des agriculteurs. L’organisation des producteurs autour de zones de stockage et d’activités de commercialisation permettrait de limiter le nombre d’intermédiaires, d’accroitre le profit des agriculteurs et de modifier les rapports de négociations souvent asymétriques entre agriculteurs et commerçants.

  5. Profil étiologique des surdités neurosensorielle sévère et profonde de l'enfant dans la région du centre-nord du Maroc

    Science.gov (United States)

    Ridal, Mohammed; Outtasi, Naouar; Taybi, Zainab; Boulouiz, Redouan; Chaouki, Sanae; Boubou, Meryem; Maaroufi, Mustapha; Benmansour, Najib; Zaki, Zouheir; Ouldim, Karim; Barakat, Hamid; Hida, Mustapha; Tizniti, Siham; El Alami, Mohamed Noreddine

    2014-01-01

    Introduction Le diagnostic d'une surdité profonde est possible dès les premiers jours de vie. Or, le développement du langage et l'intégration scolaire et professionnelle ne sont pas possible que si la surdité est prise en charge précocement. L’établissement d'un diagnostc étiologique a des implications pronostiques et thérapeutiques. Méthodes C'est une étude rétrospective allant de Juin 2009 au mois de Janvier 2012 ayant recensé 250 cas d'enfants porteurs d'une surdité sévère et profonde. Résultats La moyenne d’âge au moment de l'annonce du diagnostic est de 3.7 ans. Les étiologies prédominantes sont les surdités génétiques dans 35.6% suivies des surdités acquises dans 30.8% des cas. Dans 34.4% des cas aucune étiologie n'a pu être retrouvée. Conclusion Cette étude met en évidence la prédominance éventuelle de causes génétiques de la surdité neurosensorielle de l'enfant au Maroc, et souligne la nécessité d'améliorer les politiques de prévention des maladies infectieuses et de dépistage de la surdité néonatale. Cependant, des analyses moléculaires plus ciblées et la réalisation d'un scanner des rochers systématiques sont nécessaires pour évaluer plus précisément la contribution des étiologies génétiques. PMID:25018837

  6. Profil épidémiologique et prise en charge des exacerbations d'asthme chez l'enfant à l'hôpital d'enfants de Rabat au Maroc

    Science.gov (United States)

    Boubkraoui, Mohamed El Mahdi; Benbrahim, Fadoua; Assermouh, Abdellah; El Hafidi, Naima; Benchekroun, Soumia; Mahraoui, Chafiq

    2015-01-01

    Introduction L'exacerbation d'asthme est un phénomène paroxystique qui peut mettre en jeu le pronostic vital. Le but de l’étude est d’évaluer le profil épidémiologique et les modalités de prise en charge de l'exacerbation d'asthme chez les enfants âgés de 2 à 15 ans dans l'unité de pneumoallergologie pédiatrique de l'hôpital d'enfants de Rabat au Maroc. Méthodes Il s'agit d'une étude rétrospective qui a concerné 1461 enfants hospitalisés pour exacerbation d'asthme modérée à sévère durant une période d'un an allant de décembre 2011 à novembre 2012, les exacerbations légères étant traitées en ambulatoire. Résultats Les hospitalisations pour exacerbation d'asthme chez les enfants ont représenté 34% de l'ensemble des hospitalisations avec trois pics en mai, septembre et décembre. L’âge moyen de survenue était de 3 ans et demi avec une prédominance masculine nette. L'exacerbation d'asthme était inaugurale dans 22% des cas. Les infections respiratoires virales dominaient les facteurs déclenchants des exacerbations d'asthme. Le séjour hospitalier était en moyenne de 3 jours. Un transfert en réanimation a été nécessaire dans 2% des cas. L’évolution sous traitement a toujours été favorable et la mortalité a été nulle. Conclusion La prévalence des hospitalisations pour exacerbation d'asthme suit un profil saisonnier lié aux effets environnementaux. La plupart de ces hospitalisations pourraient cependant être évitées grâce à un meilleur contrôle de l'asthme et à l'amélioration de l’éducation thérapeutique de l'enfant asthmatique et de son entourage. PMID:26090031

  7. Les barrières à une bonne prise en charge des diabétiques dans les structures de première ligne de la province de Khouribga (MAROC)

    Science.gov (United States)

    Hassoune, Samira; Badri, Soufiane; Nani, Samira; Belhadi, Leila; Maaroufi, Abderrahmane

    2012-01-01

    Introduction Le diabète constitue un important enjeu de santé publique au Maroc et représente un défi auquel les médecins généralistes sont confrontés dans leur pratique quotidienne. Le but de ce travail était de décrire les barrières entravant une bonne prise en charge des patients diabétiques dans les structures de 1ère ligne de la province de khouribga. Méthodes Il s'agit d'une étude transversale menée de décembre 2010 à mars 2011, chez les 54 médecins généralistes (MG) exerçants dans les centres de santé de la province. La collecte des données a été réalisée à l'aide d'un questionnaire prétesté et auto administré et la saisie et l'analyse effectuées sur le logiciel SPSS 16. Résultats Huit pourcent des MG disposaient de registre informatisé pour le suivi des diabétiques. Les principales barrières à une prise en charge correcte des patients étaient le statut socio-économique faible des patients (94%), leur niveau scolaire bas (86%), le manque de moyens de traitement et de suivi (80%), le nombre insuffisant de diabétologues (80%), le manque de coordination avec les structures de 2ème ligne (74%) et l'insuffisance des séminaires de formation continue (58%). Conclusion Les médecins généralistes sont confrontés à de nombreux obstacles concernant la prise en charge des patients diabétiques. L’équipement des centres de santé en moyens diagnostiques et thérapeutiques suffisants, l'amélioration de l'accessibilité des diabétiques aux soins et la formation continue des médecins pourraient être des solutions pour améliorer cette prise en charge surtout devant la pénurie de spécialistes dans notre pays. PMID:23330033

  8. L’usage politique de l’islam : l’universel au service d’un État. Le cas du Maroc The Political Use of Islam. The Universal in the Service of a State. The Moroccan Case

    Directory of Open Access Journals (Sweden)

    Abdessamad Belhaj

    2011-03-01

    Full Text Available Lorsqu’il s’agit d’étudier les rapports des pays arabes à la mondialisation, il est nécessaire d’évoquer l’islam. En tant que facteur local, la symbolique islamique offre des ressources de légitimation au pouvoir. Le cas marocain illustre bien la manière dont les rapports existant entre le Makhzen et le répertoire religieux (Amīr al-Mu’minīne, la bayca , la chérifibilité…  font de l’introduction de la modernité un simple espace virtuel et fonctionnel. L’émergence de la contestation islamiste participe à la consécration du répertoire traditionnel. D’autre part, depuis les trois dernières décennies, l’essor de l’islam mondialisé offre au Maroc des opportunités politiques à l’échelle mondiale. Ceci est observable au niveau du rôle joué par le pays dans le cadre de la diplomatie islamique (OCI, ISESCO…  ou au niveau de son positionnement dans l’islam européen. La gestion de l’interaction entre l’islam local et l’islam global, adaptée à la conjoncture internationale, assure le maintien au pouvoir du régime.One cannot study the relationships between Arab countries and globalization without taking Islam into account for it offers symbolic support to legitimizing local power. Morocco is a good example : the relations between the royal court (Makhzen and Islamic features such as being the Commander of the Faithful or Sheriffhood make of modernity a mere virtual or functional sphere. Even the emergence of Islamic contestation contributes to the consecration of the traditional repertory. On the other hand, the rise of world Islam during the last thirty years has opened up political opportunities for Morocco on the international stage – for instance the agencies of Islamic diplomacy (OCI, ISESCO or the quest for a new role in European Islam. By managing the interaction between the local and the global, the regime is able to keep itself in power.

  9. Mercury Control With The Advanced Hybrid Particulate Collector

    International Nuclear Information System (INIS)

    Stanley J. Miller; Ye Zhuang; Jay C. Almlie

    2004-01-01

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory Program Solicitation DE-FC26-01NT41184 and specifically addresses Technical Topical Area 4 - Testing Novel and Less Mature Control Technologies on Actual Flue Gas at the Pilot Scale. The project team included the Energy and Environmental Research Center as the main contractor; W.L. Gore and Associates, Inc., as a technical and financial partner; and the Big Stone Plant operated by Otter Tail Power Company, host for the field-testing portion of the research. Since 1995, DOE has supported development of a new concept in particulate control called the advanced hybrid particulate collector (AHPC). The AHPC has been licensed to W.L. Gore and Associates, Inc., and is marketed as the Advanced Hybrid(trademark) filter by Gore. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC also appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas--solid contactor. The objective of the original five-task project was to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach included benchscale batch tests, larger-scale pilot testing with real flue gas on a coal-fired combustion system, and field demonstration at the 2.5-MW scale at a utility power plant to prove scale-up and demonstrate longer-term mercury control. The scope of work was modified to include an additional sixth task, initiated in April 2003. The objective of this task was to

  10. Source apportionment studies on particulate matter in Beijing/China

    Science.gov (United States)

    Suppan, P.; Shen, R.; Shao, L.; Schrader, S.; Schäfer, K.; Norra, S.; Vogel, B.; Cen, K.; Wang, Y.

    2013-05-01

    More than 15 million people in the greater area of Beijing are still suffering from severe air pollution levels caused by sources within the city itself but also from external impacts like severe dust storms and long range advection from the southern and central part of China. Within this context particulate matter (PM) is the major air pollutant in the greater area of Beijing (Garland et al., 2009). PM did not serve only as lead substance for air quality levels and therefore for adverse health impact effects but also for a strong influence on the climate system by changing e.g. the radiative balance. Investigations on emission reductions during the Olympic Summer Games in 2008 have caused a strong reduction on coarser particles (PM10) but not on smaller particles (PM2.5). In order to discriminate the composition of the particulate matter levels, the different behavior of coarser and smaller particles investigations on source attribution, particle characteristics and external impacts on the PM levels of the city of Beijing by measurements and modeling are performed: a) Examples of long term measurements of PM2.5 filter sampling in 2010/2011 with the objectives of detailed chemical (source attribution, carbon fraction, organic speciation and inorganic composition) and isotopic analyses as well as toxicological assessment in cooperation with several institutions (Karlsruhe Institute of Technology (IfGG/IMG), Helmholtz Zentrum München (HMGU), University Rostock (UR), Chinese University of Mining and Technology Beijing, CUMTB) will be discussed. b) The impact of dust storm events on the overall pollution level of particulate matter in the greater area of Beijing is being assessed by the online coupled comprehensive model system COSMO-ART. First results of the dust storm modeling in northern China (2011, April 30th) demonstrates very well the general behavior of the meteorological parameters temperature and humidity as well as a good agreement between modeled and

  11. Monitoring of PM10 and PM2.5 around primary particulate anthropogenic emission sources

    Science.gov (United States)

    Querol, Xavier; Alastuey, Andrés; Rodriguez, Sergio; Plana, Felicià; Mantilla, Enrique; Ruiz, Carmen R.

    Investigations on the monitoring of ambient air levels of atmospheric particulates were developed around a large source of primary anthropogenic particulate emissions: the industrial ceramic area in the province of Castelló (Eastern Spain). Although these primary particulate emissions have a coarse grain-size distribution, the atmospheric transport dominated by the breeze circulation accounts for a grain-size segregation, which results in ambient air particles occurring mainly in the 2.5-10 μm range. The chemical composition of the ceramic particulate emissions is very similar to the crustal end-member but the use of high Al, Ti and Fe as tracer elements as well as a peculiar grain-size distribution in the insoluble major phases allow us to identify the ceramic input in the bulk particulate matter. PM2.5 instead of PM10 monitoring may avoid the interference of crustal particles without a major reduction in the secondary anthropogenic load, with the exception of nitrate. However, a methodology based in PM2.5 measurement alone is not adequate for monitoring the impact of primary particulate emissions (such as ceramic emissions) on air quality, since the major ambient air particles derived from these emissions are mainly in the range of 2.5-10 μm. Consequently, in areas characterised by major secondary particulate emissions, PM2.5 monitoring should detect anthropogenic particulate pollutants without crustal particulate interference, whereas PM10 measurements should be used in areas with major primary anthropogenic particulate emissions.

  12. Application of Cyclone to Removal of Hot Particulate in Hot Cell

    International Nuclear Information System (INIS)

    Kim, Gye Nam; Lee, Sung Yeol; Won, Hui Jun; Jung, Chong Hun; Oh, Won Zin

    2005-01-01

    The size and main ingredient of hot particulate generated during the nuclide experiment in hot cells of nuclear facilities were 0.5300 μm and UO 2 . A cyclone filter equipment which consists of a cyclone and Bag/HEPA filter was devised to remove hot particulate generated during the nuclide experiment in hot cells of nuclear facilities. The experimental conditions to maximize the collection efficiency of hot particulate were suggested through experiments done with the cyclone filter equipment. With the large size of simulated particulate, the collection efficiency of the particulate was high. When the size of simulated particulate was more than 5 μm, the collection efficiency of the particulate was more than 80% and when the size of simulated particulate was less than 1.0 μm, the collection efficiency decreased by less than. If the inflow velocity of simulated particulate was increased, the collection efficiency of the particulate was also increased. When the inflow velocity of simulated particulate was more than 12 m/sec, the collection efficiency was higher than , but after 17 m/sec inflow velocity, no change observed. The collection efficiency of the simulated particulate can be enhanced with the length of vortex finder inside the chamber. With the length of vortex finder, 7.2 cm, the observed collection efficiency of the particulate was the maximum. Moreover, when the sub-cone was attached under the cyclone, the collection efficiency of cyclone increased 2%. It was found that effect by attachment of sub-cone was not serious.

  13. Avortements non médicalisés: état des lieux à travers une étude rétrospective de 451 cas traités à l'hôpital militaire d'instruction Moulay Ismail Meknès, Maroc

    Science.gov (United States)

    Laghzaoui, Omar

    2016-01-01

    L'avortement non médicalisé est un fléau dans le monde entier mais notamment en Afrique où il constitue un marché lucratif pour les tradipraticiens qui exposent les patientes à des complications graves voir mortelles. Notre étude rétrospective de 451 dossiers représente un échantillon exhaustif de cette pratique au Maroc soulevant les raisons qui poussent les femmes à l'avortement non médicalisé, la tranche d’âge la plus concernée, les conditions et les complications inhérentes à l'acte. Notre travail aboutit sur la nécessité d'intervenir avant la grossesse en développant la notion de contraception chez les jeunes filles dès la scolarité pour minimiser ces pratiques non sanitaires. PMID:27642422

  14. Effect of lubricant oil properties on the performance of gasoline particulate filter (GPF)

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Huifang; Lam, William; Remias, Joseph; Roos, Joseph; Seong, HeeJe; Choi, Seungmok

    2016-10-17

    Mobile source emissions standards are becoming more stringent and particulate emissions from gasoline direct injection (GDI) engines represent a particular challenge. Gasoline particulate filter (GPF) is deemed as one possible technical solution for particulate emissions reduction. In this work, a study was conducted on eight formulations of lubricants to determine their effect on GDI engine particulate emissions and GPF performance. Accelerated ash loading tests were conducted on a 2.4L GDI engine with engine oil injection in gasoline fuel by 2%. The matrix of eight formulations was designed with changing levels of sulfated ash (SASH) level, Zinc dialkyldithiophosphates (ZDDP) level and detergent type. Comprehensive evaluations of particulates included mass, number, size distribution, composition, morphology and soot oxidation properties. GPF performance was assessed through filtration efficiency, back pressure and morphology. It was determined that oil formulation affects the particulate emission characteristics and subsequent GPF performance.

  15. Bio-derived fuels may ease the regeneration of diesel particulate traps

    Energy Technology Data Exchange (ETDEWEB)

    E. Coda Zabetta; M. Hupa; S. Niemi [Aabo Akademi Process Chemistry Centre, Turku (Finland)

    2006-12-15

    Particulate is the most problematic emission from diesel engines. To comply with environmental regulations, these engines are often equipped with particulate traps, which must be regenerated frequently for the sake of efficiency. The regeneration is commonly achieved by rising the temperature in the trap till the particulate self-ignites. However, this method implies energy losses and thermal shocks in the trap. Alternatively, catalysts and additives have been recently considered for reducing the ignition temperature of particulate, but these techniques suffer from poisoning and undesirable byproducts. The present experimental study shows that the ignition temperature of particulate from seed-derived oils (SO) and from blends of SO with diesel fuel oil (DO) can be lower than that of particulate from neat DO. If substantiated by more extensive studies, such finding could have noteworthy implications on the future of fuels and traps. Short communication. 8 refs., 3 figs., 2 tabs.

  16. Estimating particulate matter health impact related to the combustion of different fossil fuels

    OpenAIRE

    Kuenen , Jeroen; Gschwind , Benoît; Drebszok , Kamila M.; Stetter , Daniel; Kranenburg , Richard; Hendriks , Carlijn; Lefèvre , Mireille; Blanc , Isabelle; Wyrwa , Artur; Schaap , Martijn

    2013-01-01

    International audience; Exposure to particulate matter (PM) in ambient air leads to adverse health effects. To design cost effective mitigation strategies, a thorough understanding of the sources of particulate matter is crucial. We have successfully generated a web map service that allows to access information on fuel dependent health effects due to particulate matter. For this purpose, the LOTOS-EUROS air pollution model was equipped with a source apportionment module that tracks the origin...

  17. Report Task 2.3: Particulate waste and turbidity in (marine) RAS

    OpenAIRE

    Kals, J.; Schram, E.; Brummelhuis, E.B.M.; Bakel, van, B.

    2006-01-01

    Particulate waste management and removal is one of the most problematic parts of recirculation aquaculture systems (RAS). Particulate waste and thereby turbidity originates from three major sources: fish (faeces), feed and biofilm (heterotrophic bacteria and fungi). Based on size and density there are roughly four categories of particulate waste: settable, suspended, floatable and fine or dissolved solids. Specific problems related to high turbidity are a decreasing feed intake by fish, causi...

  18. Debonding of short fibres among particulates in a metal matrix composite

    DEFF Research Database (Denmark)

    Tvergaard, Viggo

    2003-01-01

    of differently shaped fibres or particulates in each unit cell. thus representing debonding of a relatively long discontinuous fibre among particulates that do not debond. Interfacial failure is modelled in terms of a cohesive zone model that accounts for decohesion by normal separation as well as by tangential...... separation. It is found that the evolution of failure can depend rather strongly on the distribution of particulates around a fibre subject to debonding. (C) 2003 Elsevier Ltd. All rights reserved....

  19. Regions of pollution with particulate matter in Poland

    Directory of Open Access Journals (Sweden)

    Rawicki Kacper

    2018-01-01

    Full Text Available The study presents the temporal and spatial variability of particulate matter concentration in Poland in the calendar winter season (December-February. The basis for the study were the hourly and daily values of particulate matter PM10 concentration from the period 2005/06 – 2014/15, obtained from 33 air pollution monitoring stations. In Poland, the obligation to monitor the concentration of the finer fraction of particles smaller than 2.5µm in aerodynamic diameter was introduced only in 2010. Consequently, data on PM2.5 concentration refer to a shorter period, i.e. 2009/10 – 2014/15, and were obtained from 23 stations. Using the cluster analysis (k-means method, three regions of comparable variability of particulate matter concentration were delineated. The largest region, i.e. Region I, comprises the northern and eastern central area of Poland, and its southern boundary is along the line Gorzów Wlkp-Bydgoszcz-Konin-Łódź-Kielce-Lublin. Markedly smaller Region II is located to the south of Region I. By far the smallest area was designated to Region III which covers the south west area of Poland. The delineated regions show a marked variability in terms of mean concentration of both PM fractions in winter (PM10: region I - 33 µg·m-3, region II - 55 µg·m-3, region III - 83 µg·m-3; PM2,5: region I - 35 µg·m-3, region II - 50 µg·m-3, region III - 60 µg·m-3 and, in the case of PM10, the frequency of excessive daily limit value.

  20. Spatial and temporal variability in urban fine particulate matter concentrations

    International Nuclear Information System (INIS)

    Levy, Jonathan I.; Hanna, Steven R.

    2011-01-01

    Identification of hot spots for urban fine particulate matter (PM 2.5 ) concentrations is complicated by the significant contributions from regional atmospheric transport and the dependence of spatial and temporal variability on averaging time. We focus on PM 2.5 patterns in New York City, which includes significant local sources, street canyons, and upwind contributions to concentrations. A literature synthesis demonstrates that long-term (e.g., one-year) average PM 2.5 concentrations at a small number of widely-distributed monitoring sites would not show substantial variability, whereas short-term (e.g., 1-h) average measurements with high spatial density would show significant variability. Statistical analyses of ambient monitoring data as a function of wind speed and direction reinforce the significance of regional transport but show evidence of local contributions. We conclude that current monitor siting may not adequately capture PM 2.5 variability in an urban area, especially in a mega-city, reinforcing the necessity of dispersion modeling and methods for analyzing high-resolution monitoring observations. - Highlights: →Fine particulate matter (PM 2.5 ) hot spots are hard to identify in urban areas. → Literature conclusions about PM 2.5 hot spots depend on study design and methods. → Hot spots are more likely for short-term concentrations at high spatial density. → Statistical methods illustrate local source impacts beyond regional transport. → Dispersion models and high-resolution monitors are both needed to find hot spots. - Fine particulate matter can vary spatially within large urban areas, in spite of the significant contribution from regional atmospheric transport.

  1. Dynamics of particulate phosphorus in a shallow eutrophic lake

    Energy Technology Data Exchange (ETDEWEB)

    Shinohara, Ryuichiro, E-mail: r-shino@nies.go.jp [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Imai, Akio; Kohzu, Ayato; Tomioka, Noriko [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Furusato, Eiichi [Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama 338-8570 (Japan); Satou, Takayuki; Sano, Tomoharu; Komatsu, Kazuhiro; Miura, Shingo; Shimotori, Koichi [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan)

    2016-09-01

    We tested the hypothesis that in shallow, eutrophic Lake Kasumigaura, the concentration of particulate phosphorus (PP) is controlled by biogenic P (P in living or dead phytoplankton and bacterial cells), rather than by resuspension of inorganic P in sediment. Increases in wind velocity and turbidity were associated with bottom shear stress exceeding the critical value for the lake (τ{sub c} = 0.15 N m{sup −2}); this increased turbidity was due to sediment resuspension. However, concentrations of PP; HCl-extractable, reactive P in PP (P-rP); and HCl-extractable, non-reactive P in PP (P-nrP) were not correlated with wind velocity (PP vs. wind velocity: r = 0.40, p > 0.05). Rather, the P-nrP concentration accounted for approximately 79% of PP, and the concentrations of PP, P-rP, and P-nrP were correlated with the particulate organic carbon (POC) concentration (POC vs. PP: r = 0.90, p < 0.01; POC vs. P-rP: r = 0.82, p < 0.01; POC vs. P-nrP: r = 0.86, p < 0.01). In our {sup 31}P nuclear magnetic resonance spectroscopy results, mononucleotides accounted for the largest proportion among the detected P compound classes. In addition, concentrations of mononucleotides, orthophosphate, and pyrophosphate were significantly higher in samples with high POC concentrations, whereas the DNA-P concentration was not. These results suggest that biogenic P affects PP concentrations more strongly than does sediment resuspension, and the production of biogenic P creates a pool of mononucleotides, a class of easily degradable P, even in shallow, eutrophic Lake Kasumigaura. - Highlights: • Biogenic P affected the PP concentration more than did sediment resuspension. • PP correlated with particulate organic carbon concentration but not wind velocity. • Mononucleotides accounted for the largest P compound class of organic P in PP.

  2. Large scale air monitoring: Biological indicators versus air particulate matter

    International Nuclear Information System (INIS)

    Rossbach, M.; Jayasekera, R.; Kniewald, G.

    2000-01-01

    Biological indicator organisms are widely used for monitoring and banking purposes since many years. Although the complexity of the interactions between bioorganisms and their environment is generally not easily comprehensible, environmental quality assessment using the bioindicator approach offers some convincing advantages compared to direct analysis of soil, water, or air. Direct measurement of air particulates is restricted to experienced laboratories with access to expensive sampling equipment. Additionally, the amount of material collected generally is just enough for one determination per sampling and no multidimensional characterization might be possible. Further, fluctuations in air masses have a pronounced effect on the results from air filter sampling. Combining the integrating property of bioindicators with the world wide availability and uniform matrix characteristics of air particulates as a prerequisite for global monitoring of air pollution will be discussed. A new approach for sampling urban dust using large volume filtering devices installed in air conditioners of large hotel buildings is assessed. A first experiment was initiated to collect air particulates (300 to 500 g each) from a number of hotels during a period of three to four months by successive vacuum cleaning of used inlet filters from high volume air conditioning installations reflecting average concentrations per three months in different large cities. This approach is expected to be upgraded and applied for global monitoring. Highly positive correlated elements were found in lichen such as K/S, Zn/P, the rare earth elements (REE) and a significant negative correlation between Fig and Cu was observed in these samples. The ratio of concentrations of elements in dust and Usnea spp. is highest for Cr, Zn, and Fe (400-200) and lowest for elements such as Ca, Rb, and Sr (20-10). (author)

  3. Particulate Matter Concentrations in East Oakland's High Street Corridor

    Science.gov (United States)

    Lei, P.; Jackson, J.; Lewis, R.; Marigny, A.; Mitchell, J. D.; Nguyen, R.; Philips, B.; Randle, D.; Romero, D.; Spears, D.; Telles, C.; Weissman, D.

    2012-12-01

    Particulate matter (PM) is a complex mixture of small solid pieces and/or liquid droplets in the air. High concentrations of PM can pose a serious health hazard because inhalation can result in breathing problems and/or aggravate asthma. Long term exposure can increase the likelihood of respiratory problems like asthma and emphysema as well as cancer. The smaller the particles, the deeper they can get into the respiratory system. For this reason, the smallest particles, those smaller than 2.5 micrometers in diameter (PM2.5), are the most dangerous. PM2.5 is largely emitted from motor vehicles burning fuels that don't break down fully. Our research team investigated the levels of PM2.5 as well as particles smaller than 10 micrometers (PM10) and total suspended particulate (TSP) along the northeast-southwest trending High Street Corridor, near Fremont High School in East Oakland, California. Using the Aerocet 531 mass particle counter, team members walked through neighborhoods and along major roads within a 1 mile radius of Fremont High School. The Aerocet 531 recorded two minute average measurements of all the relevant PM sizes, which are reported in mg/m3. Measurements were consistently taken in the morning, between 8:30 and 11:30 am. Preliminary results indicate maximum readings of all PM sizes at sites that are in close proximity to a major freeway (Interstate-880). These results support our initial hypothesis that proximity to major roads and freeways, especially those with high diesel-fuel burning truck traffic, would be the primary factor affecting PM concentration levels. Preliminary median and maximum readings all suggest particulate matter levels below what the EPA would consider unhealthy or risky.

  4. Regions of pollution with particulate matter in Poland

    Science.gov (United States)

    Rawicki, Kacper; Czarnecka, Małgorzata; Nidzgorska-Lencewicz, Jadwiga

    2018-01-01

    The study presents the temporal and spatial variability of particulate matter concentration in Poland in the calendar winter season (December-February). The basis for the study were the hourly and daily values of particulate matter PM10 concentration from the period 2005/06 - 2014/15, obtained from 33 air pollution monitoring stations. In Poland, the obligation to monitor the concentration of the finer fraction of particles smaller than 2.5µm in aerodynamic diameter was introduced only in 2010. Consequently, data on PM2.5 concentration refer to a shorter period, i.e. 2009/10 - 2014/15, and were obtained from 23 stations. Using the cluster analysis (k-means method), three regions of comparable variability of particulate matter concentration were delineated. The largest region, i.e. Region I, comprises the northern and eastern central area of Poland, and its southern boundary is along the line Gorzów Wlkp-Bydgoszcz-Konin-Łódź-Kielce-Lublin. Markedly smaller Region II is located to the south of Region I. By far the smallest area was designated to Region III which covers the south west area of Poland. The delineated regions show a marked variability in terms of mean concentration of both PM fractions in winter (PM10: region I - 33 µg·m-3, region II - 55 µg·m-3, region III - 83 µg·m-3; PM2,5: region I - 35 µg·m-3, region II - 50 µg·m-3, region III - 60 µg·m-3) and, in the case of PM10, the frequency of excessive daily limit value.

  5. Organic speciation of size-segregated atmospheric particulate matter

    Science.gov (United States)

    Tremblay, Raphael

    Particle size and composition are key factors controlling the impacts of particulate matter (PM) on human health and the environment. A comprehensive method to characterize size-segregated PM organic content was developed, and evaluated during two field campaigns. Size-segregated particles were collected using a cascade impactor (Micro-Orifice Uniform Deposit Impactor) and a PM2.5 large volume sampler. A series of alkanes and polycyclic aromatic hydrocarbons (PAHs) were solvent extracted and quantified using a gas chromatograph coupled with a mass spectrometer (GC/MS). Large volume injections were performed using a programmable temperature vaporization (PTV) inlet to lower detection limits. The developed analysis method was evaluated during the 2001 and 2002 Intercomparison Exercise Program on Organic Contaminants in PM2.5 Air Particulate Matter led by the US National Institute of Standards and Technology (NIST). Ambient samples were collected in May 2002 as part of the Tampa Bay Regional Atmospheric Chemistry Experiment (BRACE) in Florida, USA and in July and August 2004 as part of the New England Air Quality Study - Intercontinental Transport and Chemical Transformation (NEAQS - ITCT) in New Hampshire, USA. Morphology of the collected particles was studied using scanning electron microscopy (SEM). Smaller particles (one micrometer or less) appeared to consist of solid cores surrounded by a liquid layer which is consistent with combustion particles and also possibly with particles formed and/or coated by secondary material like sulfate, nitrate and secondary organic aerosols. Source apportionment studies demonstrated the importance of stationary sources on the organic particulate matter observed at these two rural sites. Coal burning and biomass burning were found to be responsible for a large part of the observed PAHs during the field campaigns. Most of the measured PAHs were concentrated in particles smaller than one micrometer and linked to combustion sources

  6. Gaseous and particulate emissions from prescribed burning in Georgia.

    Science.gov (United States)

    Lee, Sangil; Baumann, Karsten; Schauer, James J; Sheesley, Rebecca J; Naeher, Luke P; Meinardi, Simone; Blake, Donald R; Edgerton, Eric S; Russell, Armistead G; Clements, Mark

    2005-12-01

    Prescribed burning is a significant source of fine particulate matter (PM2.5) in the southeastern United States. However, limited data exist on the emission characteristics from this source. Various organic and inorganic compounds both in the gas and particle phase were measured in the emissions of prescribed burnings conducted at two pine-dominated forest areas in Georgia. The measurements of volatile organic compounds (VOCs) and PM2.5 allowed the determination of emission factors for the flaming and smoldering stages of prescribed burnings. The VOC emission factors from smoldering were distinctly higher than those from flaming except for ethene, ethyne, and organic nitrate compounds. VOC emission factors show that emissions of certain aromatic compounds and terpenes such as alpha and beta-pinenes, which are important precursors for secondary organic aerosol (SOA), are much higher from active prescribed burnings than from fireplace wood and laboratory open burning studies. Levoglucosan is the major particulate organic compound (POC) emitted for all these studies, though its emission relative to total organic carbon (mg/g OC) differs significantly. Furthermore, cholesterol, an important fingerprint for meat cooking, was observed only in our in situ study indicating a significant release from the soil and soil organisms during open burning. Source apportionment of ambient primary fine particulate OC measured at two urban receptor locations 20-25 km downwind yields 74 +/- 11% during and immediately after the burns using our new in situ profile. In comparison with the previous source profile from laboratory simulations, however, this OC contribution is on average 27 +/- 5% lower.

  7. Interactions between particulate air pollution and temperature in air pollution mortality time series studies

    International Nuclear Information System (INIS)

    Roberts, Steven

    2004-01-01

    In many community time series studies on the effect of particulate air pollution on mortality, particulate air pollution is modeled additively. In this study, we investigated the interaction between daily particulate air pollution and daily mean temperature in Cook County, Illinois and Allegheny County, Pennsylvania, using data for the period 1987-1994. This was done through the use of joint particulate air pollution-temperature response surfaces and by stratifying the effect of particulate air pollution on mortality by temperature. Evidence that the effect of particulate air pollution on mortality may depend on temperature is found. However, the results were sensitive to the number of degrees of freedom used in the confounder adjustments, the particulate air pollution exposure measure, and how the effects of temperature on mortality are modeled. The results were less sensitive to the estimation method used--generalized linear models and natural cubic splines or generalized additive models and smoothing splines. The results of this study suggest that in community particulate air pollution mortality time series studies the possibility of an interaction between daily particulate air pollution and daily mean temperature should be considered

  8. MERCURY CONTROL WITH THE ADVANCED HYBRID PARTICULATE COLLECTOR

    International Nuclear Information System (INIS)

    Stanley J. Miller; Grant E. Dunham; Michelle R. Olderbak

    2001-01-01

    This project was awarded under U.S. Department of Energy (DOE) Program Solicitation DE-PS26-00NT40769 and specifically addresses Technical Topical Area 4-Testing Novel and Less Mature Control Technologies on Actual Flue Gas at the Pilot-Scale. The project team will include the Energy and Environmental Research Center (EERC) as the main contractor, W.L. Gore and Associates, Inc., as a technical and financial partner, and the Big Stone Power Plant operated by Otter Tail Power Company, which will host the field testing portion of the research. Since 1995, DOE has supported development of a new concept in particulate control, called the advanced hybrid particulate collector (AHPC). The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas-solid contactor. The objective of the three-task project is to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach includes bench-scale batch testing that ties the new work to previous results and links results with larger-scale pilot testing with real flue gas on a coal-fired combustion system, pilot-scale testing on a coal-fired combustion system with both a pulse-jet baghouse and an AHPC to prove or disprove the research hypotheses, and field demonstration pilot-scale testing at a utility power plant to prove scaleup and demonstrate longer-term mercury control. This project, if successful, will demonstrate at the pilot-scale level a

  9. Diesel emission control: Catalytic filters for particulate removal

    Directory of Open Access Journals (Sweden)

    Debora Fino

    2007-01-01

    Full Text Available The European diesel engine industry represents a vital sector across the Continent, with more than 2 million direct work positions and a turnover of over 400 billion Euro. Diesel engines provide large paybacks to society since they are extensively used to transport goods, services and people. In recent years increasing attention has been paid to the emissions from diesel engines which, like gasoline engine emissions, include carbon monoxide (CO, hydrocarbons (HC and oxides of nitrogen (NOx. Diesel engines also produce significant levels of particulate matter (PM, which consists mostly of carbonaceous soot and a soluble organic fraction (SOF of hydrocarbons that have condensed on the soot.

  10. Size distribution of airbone particulates in monazite dust

    International Nuclear Information System (INIS)

    Cunha, K.M.A.D. da; Carvalho, S.M.M.; Leite, C.V.B.; Baptista, G.B.; Paschoa, A.S.

    1988-01-01

    A six-stage cascade impactor was used to collect airborne dust particulates in the grinding area of a Monazite sepation plant. The samples were analysis using particle-induced X-ray emission (PIXE) to determine the elemental concentrations, with special attention to thorium and uranium concentrations. The particle size distribution of the samples containing thorium and uranium were determined. The mass median aerodynamic diameter (MMAD) obtained was 1.15 μm for both elements. The activity median aerodynamic diameter (AMAD) was estimated based on the MMAD. The results are compared with ICRP recommendations for derived air concentrations (DAC) for thorium and uranium in restricted areas [pt

  11. New Results on the Simulation of Particulate Flows

    Energy Technology Data Exchange (ETDEWEB)

    Uhlmann, M.

    2004-07-01

    We propose a new immersed boundary method for the simulation of particulate flows. The fluid solid interaction force is formulate din a direct manner, without resorting to a feed-back mechanisms and thereby avoiding the introduction of additional free parameters. The regularized delta function of Peskin (Acta Numerica, 2002) is used to pass variables between Lagrangian and Eulerian representations, providing for a smooth variation of the hydrodynamic forces while particles are in motion relative to the fixed grid. The application of this scheme to several benchmark problems in two space dimensions demonstrates its feasibility and efficiency. (Author) 9 refs.

  12. New Results on the Simulation of Particulate Flows

    International Nuclear Information System (INIS)

    Uhlmann, M.

    2004-01-01

    We propose a new immersed boundary method for the simulation of particulate flows. The fluid solid interaction force is formulated in a direct manner, without resorting to a feed-back mechanism and thereby avoiding the introduction of additional free parameters. The regularized delta function of Pekin (Acta Numerical, 2002) is used to pass variables between Lagrangian and Eulerian representations, providing for a smooth variation of the hydrodynamic forces while particles are in motion relative to the fixed grid. The application of this schemer to several benchmark problems in two space dimensions demonstrates its feasibility and efficiency. (Author) 9 refs

  13. Particulate Study on NeoProfen, a Neonatal Injectable Product.

    Science.gov (United States)

    Krishna, Aravind; Rice, Michael; Kester, Tom; Waters, Michael; Wilson, Terry

    2016-01-01

    NeoProfen or sterile ibuprofen L-lysine at 10 mg/mL ibuprofen, in 2 mL single-use Type I glass vials is often a first choice medication used to close a patent ductus arteriosus in neonatal patients from 500 to 1500 g body weight. Visible particulate matter was found in vials that were placed on a commercial stability program prior to the approved expiration date of 2 years. A combination of instrumental techniques including inductively coupled plasma-mass spectrometry, x-ray photoelectron spectroscopy, scanning electron microscopy energy dispersive x-ray spectrometry, and Raman and Fourier transform infrared microspectroscopy was used to evaluate stability, pilot batch and packaging samples in a root cause investigation. The particulate matter was shown to consist largely of ibuprofen aluminum salts of various stoichiometries. It developed over time by a substitution mechanism, in which the ibuprofen anion in solution reacts with the aluminum oxide network of the borosilicate glass giving the ibuprofen aluminum salt with =Al-OH remaining in the network. For corrective action an alternate Type I borosilicate glass vial with interior coating, not found in the original vial, was chosen for the product to prevent this occurrence. NeoProfen (sterile preservative-free ibuprofin L-lysine at 17 mg/mL in a single-use glass vial) is used to close a clinically significant patent ductus arteriosus in premature infants no more than 32 weeks gestational age. The neonatal population is especially sensitive to outside chemical, physical and environmental conditions because of incompletely developed organ systems, low birth weight and other underlying conditions. Two batches of this product were voluntarily recalled by the manufacturer, Lundbeck, and investigated for the source of particulate matter observed during a commercial stability testing program. This was found to result from an interaction between the product and the Type I borosilicate glass vial where ibuprofen

  14. Elevated exhaust temperature, zoned, electrically-heated particulate matter filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

    2012-04-17

    A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.

  15. Ash reduction system using electrically heated particulate matter filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J; He, Yongsheng [Sterling Heights, MI

    2011-08-16

    A control system for reducing ash comprises a temperature estimator module that estimates a temperature of an electrically heated particulate matter (PM) filter. A temperature and position estimator module estimates a position and temperature of an oxidation wave within the electrically heated PM filter. An ash reduction control module adjusts at least one of exhaust flow, fuel and oxygen levels in the electrically heated PM filter to adjust a position of the oxidation wave within the electrically heated PM filter based on the oxidation wave temperature and position.

  16. Computation of radionuclide particulate finite area fugitive source strengths

    Energy Technology Data Exchange (ETDEWEB)

    Fields, D E

    1983-06-01

    Atmospheric source strengths quantifying particulate re-suspension from wind and non-wind disturbance-driven processes are computed for sites of small area. These values are useful in computing downwind air concentration values to evaluate risk to exposed populations. The net source strength for the site is the sum of the wind- and disturbance-driven components. A unified source strength approach includes both classes of re-suspension processes. More research is needed to satisfactorily express the time-dependence of re-suspension parameters, especially in non-arid climates where population densities are greater. (JMT)

  17. Mechanics/heat-transfer relation for particulate materials

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, C.S.; Wang, D.G.; Rahman, K.

    1991-11-01

    The original goal of this study was to try and understand the relationship between the thermal and mechanical properties of particulate flows. Two situations were examined. The first is a study of the effects of simple shear flows, as a embryonic flow type on the apparent thermal conductivity and apparent viscosity of a dry granular flow. The second study involved fluidized beds. The original idea was to try and relate the heat transfer behavior of a fluidized bed to the particle pressure,'' the forces by only the particle phase of the two-phase mixture. (VC)

  18. Mechanics/heat-transfer relation for particulate materials. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, C.S.; Wang, D.G.; Rahman, K.

    1991-11-01

    The original goal of this study was to try and understand the relationship between the thermal and mechanical properties of particulate flows. Two situations were examined. The first is a study of the effects of simple shear flows, as a embryonic flow type on the apparent thermal conductivity and apparent viscosity of a dry granular flow. The second study involved fluidized beds. The original idea was to try and relate the heat transfer behavior of a fluidized bed to the ``particle pressure,`` the forces by only the particle phase of the two-phase mixture. (VC)

  19. A study to reduce DPM(Diesel Particulate Matter) emission

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bok Youn; Kang, Chang Hee; Jo, Young Do; Lim, Sang Taek [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    This research commenced in 1994 for the purpose of providing safety and environmental measures of underground mines where the mobile diesel equipment are operating. In this last research year, research on filtering of DPM(diesel particulate matter) has been carried out. Through the research, it was known that water scrubber is only one practical way to reduce DPM emission as of now. There are several kinds of the sophisticated DPM filters, but it is not practical yet to be used in underground equipment due to the many adverse effects of the devices such as tremendous increase of SOx, NOx and back pressure etc. (author). 1 tab., 3 figs.

  20. Infiltration processing of metal matrix composites using coated ceramic particulates

    Science.gov (United States)

    Leon-Patino, Carlos Alberto

    2001-07-01

    A new process was developed to fabricate particulate metal matrix composites (MMCs). The process involves three steps: (1) modifying the particulate surface by metal coating, (2) forming a particulate porous compact; and (3) introducing metal into the channel network by vacuum infiltration. MMCs with different reinforcements, volume fractions, and sizes can be produced by this technique. Powders of alumina and silicon carbide were successfully coated with nickel and copper in preparation for infiltration with molten aluminum. Electroless Ni and Cu deposition was used since it enhances the wettability of the reinforcements for composite fabrication. While Cu deposits were polycrystalline, traces of phosphorous co-deposited from the electroless bath gave an amorphous Ni-P coating. The effect of metal coating on wetting behavior was evaluated at 800°C on plain and metal-coated ceramic plates using a sessile drop technique. The metallic films eliminated the non-wetting behavior of the uncoated ceramics, leading to equilibrium contact angles in the order of 12° and below 58° for Ni and Cu coated ceramics, respectively. The spreading data indicated that local diffusion at the triple junction was the governing mechanism of the wetting process. Precipitation of intermetallic phases in the drop/ceramic interface delayed the formation of Al4C3. Infiltration with molten Al showed that the coated-particulates are suitable as reinforcing materials for fabricating MMCs, giving porosity-free components with a homogeneously distributed reinforcing phase. The coating promoted easy metal flow through the preform, compared to the non-infiltration behavior of the uncoated counterparts. Liquid state diffusion kinetics due to temperature dependent viscosity forces controlled the infiltration process. Microstructural analysis indicated the formation of intermetallic phases such as CuAl 2, in the case of Cu coating, and Ni2Al3 and NiAl 3 when Ni-coated powders were infiltrated. The

  1. PIXE analysis of atmospheric particulate matter in glas fibre filters

    International Nuclear Information System (INIS)

    Tabacniks, M.H.; Orsini, C.Q.; Maenhaut, W.

    1993-01-01

    A 3-step extraction procedure was developed to allow particle-induced X-ray emission (PIXE) analysis of particulate matter in normal glass fibre filter samples. The detection limits, expressed in ng/m 3 of air, for the filter extracts were 5 to 30 times lower than those achieved by PIXE analysis or ordinary Nuclepore polycarbonate filter samples. The concentration results were compared with those obtained from routine atomic absorption spectrometry measurements and with the PIXE data from Nuclepore stacked filter unit samples taken in parallel. (orig.)

  2. Comparison of Particulate Mercury Measured with Manual and Automated Methods

    Directory of Open Access Journals (Sweden)

    Rachel Russo

    2011-01-01

    Full Text Available A study was conducted to compare measuring particulate mercury (HgP with the manual filter method and the automated Tekran system. Simultaneous measurements were conducted with the Tekran and Teflon filter methodologies in the marine and coastal continental atmospheres. Overall, the filter HgP values were on the average 21% higher than the Tekran HgP, and >85% of the data were outside of ±25% region surrounding the 1:1 line. In some cases the filter values were as much as 3-fold greater, with

  3. Aged riverine particulate organic carbon in four UK catchments

    International Nuclear Information System (INIS)

    Adams, Jessica L.; Tipping, Edward; Bryant, Charlotte L.; Helliwell, Rachel C.; Toberman, Hannah; Quinton, John

    2015-01-01

    The riverine transport of particulate organic matter (POM) is a significant flux in the carbon cycle, and affects macronutrients and contaminants. We used radiocarbon to characterise POM at 9 riverine sites of four UK catchments (Avon, Conwy, Dee, Ribble) over a one-year period. High-discharge samples were collected on three or four occasions at each site. Suspended particulate matter (SPM) was obtained by centrifugation, and the samples were analysed for carbon isotopes. Concentrations of SPM and SPM organic carbon (OC) contents were also determined, and were found to have a significant negative correlation. For the 7 rivers draining predominantly rural catchments, PO 14 C values, expressed as percent modern carbon absolute (pMC), varied little among samplings at each site, and there was no significant difference in the average values among the sites. The overall average PO 14 C value for the 7 sites of 91.2 pMC corresponded to an average age of 680 14 C years, but this value arises from the mixing of differently-aged components, and therefore significant amounts of organic matter older than the average value are present in the samples. Although topsoil erosion is probably the major source of the riverine POM, the average PO 14 C value is appreciably lower than topsoil values (which are typically 100 pMC). This is most likely explained by inputs of older subsoil OC from bank erosion, or the preferential loss of high- 14 C topsoil organic matter by mineralisation during riverine transport. The significantly lower average PO 14 C of samples from the River Calder (76.6 pMC), can be ascribed to components containing little or no radiocarbon, derived either from industrial sources or historical coal mining, and this effect is also seen in the River Ribble, downstream of its confluence with the Calder. At the global scale, the results significantly expand available information for PO 14 C in rivers draining catchments with low erosion rates. - Highlights:

  4. Residual stress of particulate polymer composites with reduced thermal expansion

    International Nuclear Information System (INIS)

    Nishino, T; Kotera, M; Sugiura, Y

    2009-01-01

    Thermal expansion behavior was investigated for tangusten zirconium phosphate (Zr 2 (WO 4 )(PO 4 ) 2 (ZWP)) particulate filled poly(ether ether ketone) (PEEK) composite. ZWP is known as ceramic filler with a negative thermal expansion. By incorporating ZWP with 40 volume %, the linear thermal expansion coefficient of the PEEK composite was reduced to almost same value (2.53 X 10 -5 K -1 ) with that of aluminum. This decrease was found to be quite effective for the decrease of the residual stress at the interface between aluminum plate and the composite.

  5. Aged riverine particulate organic carbon in four UK catchments

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Jessica L., E-mail: jesams@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Tipping, Edward, E-mail: et@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); Bryant, Charlotte L., E-mail: charlotte.bryant@glasgow.ac.uk [NERC Radiocarbon Facility, East Kilbride G75 0QF, Scotland (United Kingdom); Helliwell, Rachel C., E-mail: rachel.helliwell@hutton.ac.uk [The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH Scotland (United Kingdom); Toberman, Hannah, E-mail: hannahtoberman@hotmail.com [Centre for Ecology and Hydrology, Lancaster Environment Centre, Lancaster, LA1 4AP (United Kingdom); School of Environmental Sciences, University of Liverpool, Liverpool L69 3GP (United Kingdom); Quinton, John, E-mail: j.quinton@lancaster.ac.uk [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom)

    2015-12-01

    The riverine transport of particulate organic matter (POM) is a significant flux in the carbon cycle, and affects macronutrients and contaminants. We used radiocarbon to characterise POM at 9 riverine sites of four UK catchments (Avon, Conwy, Dee, Ribble) over a one-year period. High-discharge samples were collected on three or four occasions at each site. Suspended particulate matter (SPM) was obtained by centrifugation, and the samples were analysed for carbon isotopes. Concentrations of SPM and SPM organic carbon (OC) contents were also determined, and were found to have a significant negative correlation. For the 7 rivers draining predominantly rural catchments, PO{sup 14}C values, expressed as percent modern carbon absolute (pMC), varied little among samplings at each site, and there was no significant difference in the average values among the sites. The overall average PO{sup 14}C value for the 7 sites of 91.2 pMC corresponded to an average age of 680 {sup 14}C years, but this value arises from the mixing of differently-aged components, and therefore significant amounts of organic matter older than the average value are present in the samples. Although topsoil erosion is probably the major source of the riverine POM, the average PO{sup 14}C value is appreciably lower than topsoil values (which are typically 100 pMC). This is most likely explained by inputs of older subsoil OC from bank erosion, or the preferential loss of high-{sup 14}C topsoil organic matter by mineralisation during riverine transport. The significantly lower average PO{sup 14}C of samples from the River Calder (76.6 pMC), can be ascribed to components containing little or no radiocarbon, derived either from industrial sources or historical coal mining, and this effect is also seen in the River Ribble, downstream of its confluence with the Calder. At the global scale, the results significantly expand available information for PO{sup 14}C in rivers draining catchments with low erosion rates

  6. Surface water, particulate matter, and sediments of inland waters

    International Nuclear Information System (INIS)

    Mundschenk, H.

    1985-01-01

    The Bundesanstalt fuer Gewaesserkunde (BfG) since 1958 runs a system for monitoring the surface water and sediments of Federal German waterways in its capacity as a directing water monitoring centre. The data recorded over the years show that the radioactivity released by the various emission sources leads to radionuclide concentrations in water, particulate matter, or sediments that generally are below the detection limits defined in the relevant legal provisions governing monitoring and surveillance of nuclear facilities effluents. Representative examples of measuring methods and results (as for e.g. for H-3) are given. (DG) [de

  7. Particulate organic nitrates: Sampling and night/day variation

    DEFF Research Database (Denmark)

    Nielsen, T.; Platz, J.; Granby, K.

    1998-01-01

    Atmospheric day and night concentrations of particulate organic nitrates (PON) and several other air pollutants were measured in the summer 1995 over an open-land area in Denmark. The sampling of PON was evaluated comparing 24 h samples with two sets of 12 h samples. These results indicate...... that the observed low contribution of PON to NO, is real and not the result of an extensive loss during the sampling. Empirical relationships between the vapour pressure and chemical formula of organic compounds were established in order to evaluate the gas/particle distribution of organic nitrates. A positive...

  8. The filtering effect of buildings on airborne particulate matter

    International Nuclear Information System (INIS)

    Christensen, G.C.; Mustonen, R.

    1987-06-01

    Within the radioecological programme of the Nordic Liaison Committee for Atomic Energy (NKA), the possible consequences of a major reactor accident are one of its main research branches. This study of the filtering effect of buildings on airborne particulate matter has been one part of this branch. The absorbed dose to a person from a passing radioactive cloud will be lower if he has been indoors and not ourdoors during the cloud passage. The aim of this study has been to find filtering factors for typical Finnish and Norwegian houses to use in model work

  9. Characterization of coarse particulate matter in school gyms.

    Science.gov (United States)

    Braniš, Martin; Šafránek, Jiří

    2011-05-01

    We investigated the mass concentration, mineral composition and morphology of particles resuspended by children during scheduled physical education in urban, suburban and rural elementary school gyms in Prague (Czech Republic). Cascade impactors were deployed to sample the particulate matter. Two fractions of coarse particulate matter (PM(10-2.5) and PM(2.5-1.0)) were characterized by gravimetry, energy dispersive X-ray spectrometry and scanning electron microscopy. Two indicators of human activity, the number of exercising children and the number of physical education hours, were also recorded. Lower mass concentrations of coarse particulate matter were recorded outdoors (average PM(10-2.5) 4.1-7.4 μg m(-3) and PM(2.5-1.0) 2.0-3.3 μg m(-3)) than indoors (average PM(10-2.5) 13.6-26.7 μg m(-3) and PM(2.5-1.0) 3.7-7.4 μg m(-3)). The indoor concentrations of coarse aerosol were elevated during days with scheduled physical education with an average indoor-outdoor (I/O) ratio of 2.5-16.3 for the PM(10-2.5) and 1.4-4.8 for the PM(2.5-1.0) values. Under extreme conditions, the I/O ratios reached 180 (PM(10-2.5)) and 19.1 (PM(2.5-1.0)). The multiple regression analysis based on the number of students and outdoor coarse PM as independent variables showed that the main predictor of the indoor coarse PM concentrations is the number of students in the gym. The effect of outdoor coarse PM was weak and inconsistent. The regression models for the three schools explained 60-70% of the particular dataset variability. X-ray spectrometry revealed 6 main groups of minerals contributing to resuspended indoor dust. The most abundant particles were those of crustal origin composed of Si, Al, O and Ca. Scanning electron microscopy showed that, in addition to numerous inorganic particles, various types of fibers and particularly skin scales make up the main part of the resuspended dust in the gyms. In conclusion, school gyms were found to be indoor microenvironments with high

  10. A Li-particulate blanket concept for ITER

    International Nuclear Information System (INIS)

    Wong, C.P.C.; Cheng, E.T.; Creedon, R.L.

    1989-01-01

    The Li-particulate blanket design concept the authors proposed for the International Thermonuclear Experimental Reactor (ITER) uses a dilute suspension of fine solid breeder particles in a carrier gas as the combined coolant and lithium breeder stream. This blanket concept has a simple mechanical and hydraulic configuration, low inventory of bred tritium, and simple tritium extraction system. Existing technology can be used to implement the design for ITER. The concept has the potential to be a highly reliable shield and blanket design for ITER with relatively low development and capital costs

  11. Silkworm cocoons inspire models for random fiber and particulate composites

    Energy Technology Data Exchange (ETDEWEB)

    Fujia, Chen; Porter, David; Vollrath, Fritz [Department of Zoology, University of Oxford, Oxford OX1 3PS (United Kingdom)

    2010-10-15

    The bioengineering design principles evolved in silkworm cocoons make them ideal natural prototypes and models for structural composites. Cocoons depend for their stiffness and strength on the connectivity of bonding between their constituent materials of silk fibers and sericin binder. Strain-activated mechanisms for loss of bonding connectivity in cocoons can be translated directly into a surprisingly simple yet universal set of physically realistic as well as predictive quantitative structure-property relations for a wide range of technologically important fiber and particulate composite materials.

  12. Monitoring diesel particulate matter and calculating diesel particulate densities using Grimm model 1.109 real-time aerosol monitors in underground mines.

    Science.gov (United States)

    Kimbal, Kyle C; Pahler, Leon; Larson, Rodney; VanDerslice, Jim

    2012-01-01

    Currently, there is no Mine Safety and Health Administration (MSHA)-approved sampling method that provides real-time results for ambient concentrations of diesel particulates. This study investigated whether a commercially available aerosol spectrometer, the Grimm Portable Aerosol Spectrometer Model 1.109, could be used during underground mine operations to provide accurate real-time diesel particulate data relative to MSHA-approved cassette-based sampling methods. A subset was to estimate size-specific diesel particle densities to potentially improve the diesel particulate concentration estimates using the aerosol monitor. Concurrent sampling was conducted during underground metal mine operations using six duplicate diesel particulate cassettes, according to the MSHA-approved method, and two identical Grimm Model 1.109 instruments. Linear regression was used to develop adjustment factors relating the Grimm results to the average of the cassette results. Statistical models using the Grimm data produced predicted diesel particulate concentrations that highly correlated with the time-weighted average cassette results (R(2) = 0.86, 0.88). Size-specific diesel particulate densities were not constant over the range of particle diameters observed. The variance of the calculated diesel particulate densities by particle diameter size supports the current understanding that diesel emissions are a mixture of particulate aerosols and a complex host of gases and vapors not limited to elemental and organic carbon. Finally, diesel particulate concentrations measured by the Grimm Model 1.109 can be adjusted to provide sufficiently accurate real-time air monitoring data for an underground mining environment.

  13. Efficiency of Respirator Filter Media against Diesel Particulate Matter: A Comparison Study Using Two Diesel Particulate Sources.

    Science.gov (United States)

    Burton, Kerrie A; Whitelaw, Jane L; Jones, Alison L; Davies, Brian

    2016-07-01

    Diesel engines have been a mainstay within many industries since the early 1900s. Exposure to diesel particulate matter (DPM) is a major issue in many industrial workplaces given the potential for serious health impacts to exposed workers; including the potential for lung cancer and adverse irritant and cardiovascular effects. Personal respiratory protective devices are an accepted safety measure to mitigate worker exposure against the potentially damaging health impacts of DPM. To be protective, they need to act as effective filters against carbon and other particulates. In Australia, the filtering efficiency of respiratory protective devices is determined by challenging test filter media with aerosolised sodium chloride to determine penetration at designated flow rates. The methodology outlined in AS/NZS1716 (Standards Australia International Ltd and Standards New Zealand 2012. Respiratory protective devices. Sydney/Wellington: SAI Global Limited/Standards New Zealand) does not account for the differences between characteristics of workplace contaminants like DPM and sodium chloride such as structure, composition, and particle size. This study examined filtering efficiency for three commonly used AS/NZS certified respirator filter models, challenging them with two types of diesel emissions; those from a diesel generator and a diesel engine. Penetration through the filter media of elemental carbon (EC), total carbon (TC), and total suspended particulate (TSP) was calculated. Results indicate that filtering efficiency assumed by P2 certification in Australia was achieved for two of the three respirator models for DPM generated using the small diesel generator, whilst when the larger diesel engine was used, filtering efficiency requirements were met for all three filter models. These results suggest that the testing methodology specified for certification of personal respiratory protective devices by Standards Australia may not ensure adequate protection for

  14. Miniaturized inertial impactor for personal airborne particulate monitoring: Prototyping

    Science.gov (United States)

    Pasini, Silvia; Bianchi, Elena; Dubini, Gabriele; Cortelezzi, Luca

    2017-11-01

    Computational fluid dynamic (CFD) simulations allowed us to conceive and design a miniaturized inertial impactor able to collect fine airborne particulate matter (PM10, PM2.5 and PM1). We created, by 3D printing, a prototype of the impactor. We first performed a set of experiments by applying a suction pump to the outlets and sampling the airborne particulate of our laboratory. The analysis of the slide showed a collection of a large number of particles, spanning a wide range of sizes, organized in a narrow band located below the exit of the nozzle. In order to show that our miniaturized inertial impactor can be truly used as a personal air-quality monitor, we performed a second set of experiments where the suction needed to produce the airflow through the impactor is generated by a human being inhaling through the outlets of the prototype. To guarantee a number of particles sufficient to perform a quantitative characterization, we collected particles performing ten consecutive deep inhalations. Finally, the potentiality for realistic applications of our miniaturized inertial impactor used in combination with a miniaturized single-particle detector will be discussed. CARIPLO Fundation - project MINUTE (Grant No. 2011-2118).

  15. Microfluidic paper-based analytical device for particulate metals.

    Science.gov (United States)

    Mentele, Mallory M; Cunningham, Josephine; Koehler, Kirsten; Volckens, John; Henry, Charles S

    2012-05-15

    A microfluidic paper-based analytical device (μPAD) fabricated by wax printing was designed to assess occupational exposure to metal-containing aerosols. This method employs rapid digestion of particulate metals using microliters of acid added directly to a punch taken from an air sampling filter. Punches were then placed on a μPAD, and digested metals were transported to detection reservoirs upon addition of water. These reservoirs contained reagents for colorimetric detection of Fe, Cu, and Ni. Dried buffer components were used to set the optimal pH in each detection reservoir, while precomplexation agents were deposited in the channels between the sample and detection zones to minimize interferences from competing metals. Metal concentrations were quantified from color intensity images using a scanner in conjunction with image processing software. Reproducible, log-linear calibration curves were generated for each metal, with method detection limits ranging from 1.0 to 1.5 μg for each metal (i.e., total mass present on the μPAD). Finally, a standard incineration ash sample was aerosolized, collected on filters, and analyzed for the three metals of interest. Analysis of this collected aerosol sample using a μPAD showed good correlation with known amounts of the metals present in the sample. This technology can provide rapid assessment of particulate metal concentrations at or below current regulatory limits and at dramatically reduced cost.

  16. Collaboration in air particulate analysis through sharing of regional resources

    International Nuclear Information System (INIS)

    Santos, Flora L.

    2003-01-01

    The air pollution research program of the Philippine Nuclear Research Institute is being pursued in support of the 1999 Clean Air Act. This is being undertaken as part of the RCA/IAEA subproject, 'Air Pollution and Its Trends'. Since the PNRI research reactor (PRR-I) has been on extended shut down for the past 18 years, the PNRI depends solely on X-ray Fluorescence (XRF) spectrometry for elemental characterization of air particulate samples. NAA is a powerful and efficient tool in air particulate characterization and is used in many national programs in the region. Collaboration in air pollution studies through exchange of samples between XRF and NAA groups will widen the range of elements that could be detected by one group. In the RCA/IAEA RAS/4/020, 'Improvement of Research Reactor Operation and Utilization' sharing of research reactor facilities is encouraged. Working out of mechanisms for such sharing will be advantageous to research groups without operational research reactors. This could take the form of exchange of samples or fellowship at a regional host institution. This will allow training of technical staff from countries without research reactors, thus ensuring continuing expertise in NAA even after long periods of reactor shutdown. (author)

  17. Toward Distinguishing Woodsmoke and Diesel Exhaust in Ambient Particulate Matter

    International Nuclear Information System (INIS)

    Braun, A.; Huggins, F.; Kubatova, A.; Wirick, S.; Maricq, M.; Mun, B.; McDonald, J.; Kelly, K.; Shah, N.; Huffman, G.

    2008-01-01

    Particulate matter (PM) from biomass burning and diesel exhaust has distinct X-ray spectroscopic, carbon specific signatures, which can be employed for source apportionment. Characterization of the functional groups of a wide selection of PM samples (woodsmoke, diesel soot, urban air PM) was carried out using the soft X-ray spectroscopy capabilities at the synchrotron radiation sources in Berkeley (ALS) and Brookhaven (NSLS). The spectra reveal that diesel exhaust particulate (DEP) matter is made up from a semigraphitic solid core and soluble organic matter, predominantly with carboxylic functional groups. Woodsmoke PM has no or a less prevalent, graphitic signature, instead it contains carbon-hydroxyl groups. Using these features to apportion the carbonaceous PM in ambient samples we estimate that the relative contribution of DEP to ambient PM in an urban area such as Lexington, KY and St. Louis, MO is 7% and 13.5%, respectively. These values are comparable to dispersion modeling data from nonurban and urban areas in California, and with elemental carbon measurements in urban locations such as Boston, MA, Rochester, NY, and Washington, DC.

  18. Characterization of Urban Runoff Pollution between Dissolved and Particulate Phases

    Science.gov (United States)

    Wei, Zhang; Simin, Li; Fengbing, Tang

    2013-01-01

    To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC) of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitrogen, and total dissolved phosphorus in total ones for all the catchments were 26.19%–30.91%, 83.29%–90.51%, and 61.54–68.09%, respectively. During rainfall events, the pollutant concentration at the initial stage of rainfall was high and then sharply decreased to a low value. Affected by catchments characterization and rainfall distribution, the highest concentration of road pollutants might appear in the later period of rainfall. Strong correlations were also found among runoffs pollutants in different phases. Total suspended solid could be considered as a surrogate for particulate matters in both road and roof runoff, while dissolved chemical oxygen demand could be regarded as a surrogate for dissolved matters in roof runoff. PMID:23935444

  19. Characterization of urban runoff pollution between dissolved and particulate phases.

    Science.gov (United States)

    Wei, Zhang; Simin, Li; Fengbing, Tang

    2013-01-01

    To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC) of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitrogen, and total dissolved phosphorus in total ones for all the catchments were 26.19%-30.91%, 83.29%-90.51%, and 61.54-68.09%, respectively. During rainfall events, the pollutant concentration at the initial stage of rainfall was high and then sharply decreased to a low value. Affected by catchments characterization and rainfall distribution, the highest concentration of road pollutants might appear in the later period of rainfall. Strong correlations were also found among runoffs pollutants in different phases. Total suspended solid could be considered as a surrogate for particulate matters in both road and roof runoff, while dissolved chemical oxygen demand could be regarded as a surrogate for dissolved matters in roof runoff.

  20. Standard Practice for Sampling for Particulate Contamination by Tape Lift

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This practice covers procedures for sampling surfaces to determine the presence of particulate contamination, 5 m and larger. The practice consists of the application of a pressure-sensitive tape to the surface followed by the removal of particulate contamination with the removal of the tape. The tape with the adhering particles is then mounted on counting slides. Counting and measuring of particles is done by standard techniques. 1.2 This practice describes the materials and equipment required to perform sampling of surfaces for particle counting and sizing. 1.3 The criteria for acceptance or rejection of a part for conformance to surface cleanliness level requirements shall be determined by the user and are not included in this practice. 1.4 This practice is for use on surfaces that are not damaged by the application of adhesive tape. The use of this practice on any surface of any material not previously tested or for which the susceptibility to damage is unknown is not recommended. In general, metal...

  1. Effective moduli of high volume fraction particulate composites

    International Nuclear Information System (INIS)

    Kwon, P.; Dharan, C.K.H.

    1995-01-01

    Predictions using current micromechanics theories for the effective moduli of particulate-reinforced composites tend to break down at high volume fractions of the reinforcing phase. The predictions are usually well below experimentally measured values of the Young's modulus for volume fractions exceeding about 0.6. In this paper, the concept of contiguity, which is a measure of phase continuity, is applied to Mori-Tanaka micromechanics theory. It is shown that contiguity of the second phase increases with volume fraction, leading eventually to a reversal in the roles of the inclusion and matrix. In powder metallurgy practice, it is well known that at high volume fractions, sintering and consolidation of the reinforcement make it increasingly continuous and more like the matrix phase, while the former matrix tends to become more like the inclusion phase. The concept of contiguity applied to micromechanics theory results in very good agreement between the predicted Young's modulus and experimental data on tungsten carbide particulate-reinforced cobalt

  2. Les particules et leurs symétries

    CERN Document Server

    Chanfray, Guy

    1997-01-01

    Les particules élémentaires, initialement au nombre de trois (proton, neutron, électron) se sont rapidement révélées plus nombreuses, notamment grâce aux expériences menées dans des accélérateurs de plus en plus puissants. L'interprétation théorique des données a permis de fonder une classification qui permet aujourd'hui de parler des " vrais " constituants fondamentaux : les quards et les leptons. Ce livre expose la manière dont les lois de symétrie, externes et internes, déterminent les propriétés des particules élémentaires. Il montre comment ces symétries mènent aux lois de conservation, comment le formalisme canonique de la théorie des champs permet de retrouver les diagrammes de Feynman et comment la compréhension des symétries SU(2) et SU (3)F détermine la classification des hadrons en multiples. La deuxième partie de l'ouvrage est consacrée aux grandes théories de jauge, la chromodynamique quantique et la théorie électrofaible. La QCD permet aujourd'hui de comprendre la...

  3. Multiscale Modeling of Dewetting Damage in Highly Filled Particulate Composites

    Science.gov (United States)

    Geubelle, P. H.; Inglis, H. M.; Kramer, J. D.; Patel, J. J.; Kumar, N. C.; Tan, H.

    2008-02-01

    Particle debonding or dewetting constitutes one of the key damage processes in highly filled particulate composites such as solid propellant and other energetic materials. To analyze this failure process, we have developed a multiscale finite element framework that combines, at the microscale, a nonlinear description of the binder response with a cohesive model of the damage process taking place in a representative periodic unit cell (PUC). To relate micro-scale damage to the macroscopic constitutive response of the material, we employ the mathematical theory of homogenization (MTH). After a description of the numerical scheme, we present the results of the damage response of a highly filled particulate composite subjected to a uniaxial macroscopic strain, and show the direct correlation between the complex damage processes taking place in the PUC and the nonlinear macroscopic constitutive response. We also present a detailed study of the PUC size and a comparison between the finite element MTH-based study and a micromechanics model of the dewetting process.

  4. Modifying Char Dustcake Pressure Drop Using Particulate Additives

    Energy Technology Data Exchange (ETDEWEB)

    Landham, C.; Dahlin, R.S.; Martin, R.A.; Guan, X.

    2002-09-19

    Coal gasification produces residual particles of coal char, coal ash, and sorbent that are suspended in the fuel gas stream exiting the gasifier. In most cases, these particles (referred to, hereafter, simply as char) must be removed from the stream prior to sending the gas to a turbine, fuel cell, or other downstream device. Currently, the most common approach to cleaning the gas stream at high temperature and pressure is by filtering the particulate with a porous ceramic or metal filter. However, because these dusts frequently have small size distributions, irregular morphology, and high specific surface areas, they can have very high gas flow resistance resulting in hot-gas filter system operating problems. Typical of gasification chars, the hot-gas filter dustcakes produced at the Power Systems Development Facility (PSDF) during recent coal gasification tests have had very high flow resistance (Martin et al, 2002). The filter system has been able to successfully operate, but pressure drops have been high and filter cleaning must occur very frequently. In anticipation of this problem, a study was conducted to investigate ways of reducing dustcake pressure drop. This paper will discuss the efficacy of adding low-flow-resistance particulate matter to the high-flow-resistance char dustcake to reduce dustcake pressure drop. The study had two parts: a laboratory screening study and confirming field measurements at the PSDF.

  5. Characterisation of particulate matter on airborne pollen grains

    International Nuclear Information System (INIS)

    Ribeiro, Helena; Guimarães, Fernanda; Duque, Laura; Noronha, Fernando; Abreu, Ilda

    2015-01-01

    A characterization of the physical–chemical composition of the atmospheric PM adsorbed to airborne pollen was performed. Airborne pollen was sampled using a Hirst-type volumetric spore sampler and observed using a Field Emission Electron Probe Microanalyser for PM analysis. A secondary electron image was taken of each pollen grain and EDS spectra were obtained for individually adsorbed particles. All images were analysed and the size parameters of the particles adsorbed to pollen was determined. The measured particles’ equivalent diameter varied between 0.1 and 25.8 μm, mostly in the fine fraction. The dominant particulates identified were Si-rich, Organic-rich, SO-rich, Metals & Oxides and Cl-rich. Significant daily differences were observed in the physical–chemical characteristics of particles adsorbed to the airborne pollen wall. These differences were correlated with weather parameters and atmospheric PM concentration. Airborne pollen has the ability to adsorb fine particles that may enhance its allergenicity. - Highlights: • Airborne pollen sorbs other PM found in suspension. • 84% of the particles sorbed belonged to the fine aerosol fraction. • Adsorbed PM presented daily physical–chemical variations. • Particles sorbed dominated by Si-rich, Organic-rich, SO-rich, Fe-rich and Cl-rich. - Airborne pollen is able to transport finer particulate matter, which presents daily physical–chemical variations.

  6. Fabrication of particulate metal fuel for fast burner reactors

    International Nuclear Information System (INIS)

    Ryu, Ho Jin; Lee, Sun Yong; Kim, Jong Hwan; Woo, Yoon Myung; Ko, Young Mo; Kim, Ki Hwan; Park, Jong Man; Lee, Chan Bok

    2012-01-01

    U Zr metallic fuel for sodium cooled fast reactors is now being developed by KAERI as a national R and D program of Korea. In order to recycle transuranic elements (TRU) retained in spent nuclear fuel, remote fabrication capability in a shielded hot cell should be prepared. Moreover, generation of long lived radioactive wastes and loss of volatile species should be minimized during the recycled fuel fabrication step. Therefore, innovative fuel concepts should be developed to address the fabrication challenges pertaining to TRU while maintaining good performances of metallic fuel. Particulate fuel concepts have already been proposed and tested at several experimental fast reactor systems and vipac ceramic fuel of RIAR, Russia is one of the examples. However, much less work has been reported for particulate metallic fuel development. Spherical uranium alloy particles with various diameters can be easily produced by the centrifugal atomization technique developed by KAERI. Using the atomized uranium and uranium zirconium alloy particles, we fabricated various kinds of powder pack, powder compacts and sintered pellets. The microstructures and properties of the powder pack and pellets are presented

  7. Particulate air pollution and vascular reactivity: the bus stop study.

    Science.gov (United States)

    Dales, Robert; Liu, Ling; Szyszkowicz, Mietek; Dalipaj, Mary; Willey, Jeff; Kulka, Ryan; Ruddy, Terrence D

    2007-11-01

    Particulate air pollution is associated with cardiovascular morbidity but mechanisms are not well understood. We tested the effects on vascular reactivity of exposure to fine particulates matter mass (PM(2.5)), number of particles bus stops. Flow-mediated vasodilation (FMD) of the brachial artery was then measured by ultrasound and expressed as: (maximum artery diameter after release of a blood pressure cuff inflated above systolic pressure-baseline resting diameter)/baseline resting diameter. A 30 microg/m(3) increase in PM(2.5) exposure corresponded to a 0.48% reduction in FMD, P=0.05 representing a 5% relative change in the maximum ability to dilate. Results were consistent between the two bus stops and not sensitive to type of analysis. No significant association was found between FMD and NO(2), PM(1.0) or traffic density. PM(2.5) may reduce the capacity to vasodilate, a potential explanation for the documented association with cardiovascular morbidity.

  8. Impacts modeling using the SPH particulate method. Case study

    International Nuclear Information System (INIS)

    Debord, R.

    1999-01-01

    The aim of this study is the modeling of the impact of melted metal on the reactor vessel head in the case of a core-meltdown accident. Modeling using the classical finite-element method alone is not sufficient but requires a coupling with particulate methods in order to take into account the behaviour of the corium. After a general introduction about particulate methods, the Nabor and SPH (smoothed particle hydrodynamics) methods are described. Then, the theoretical and numerical reliability of the SPH method is determined using simple cases. In particular, the number of neighbours significantly influences the preciseness of calculations. Also, the mesh of the structure must be adapted to the mesh of the fluid in order to reduce the edge effects. Finally, this study has shown that the values of artificial velocity coefficients used in the simulation of the BERDA test performed by the FZK Karlsruhe (Germany) are not correct. The domain of use of these coefficients was precised during a low speed impact. (J.S.)

  9. Particulate matter analysis at elementary schools in Curitiba, Brazil.

    Science.gov (United States)

    Avigo, Devanir; Godoi, Ana F L; Janissek, Paulo R; Makarovska, Yaroslava; Krata, Agnieszka; Potgieter-Vermaak, Sanja; Alfoldy, Balint; Van Grieken, René; Godoi, Ricardo H M

    2008-06-01

    The particulate matter indoors and outdoors of the classrooms at two schools in Curitiba, Brazil, was characterised in order to assess the indoor air quality. Information concerning the bulk composition was provided by energy-dispersive x-ray fluorescence (EDXRF). From the calculated indoor/outdoor ratios and the enrichment factors it was observed that S-, Cl- and Zn-rich particles are of concern in the indoor environment. In the present research, the chemical compositions of individual particles were quantitatively elucidated, including low-Z components like C, N and O, as well as higher-Z elements, using automated electron probe microanalysis low Z EPMA. Samples were further analysed for chemical and morphological aspects, determining the particle size distribution and classifying them according to elemental composition associations. Five classes were identified based on major elemental concentrations: aluminosilicate, soot, organic, calcium carbonate and iron-rich particles. The majority of the respirable particulate matter found inside of the classroom was composed of soot, biogenic and aluminosilicate particles. In view of the chemical composition and size distribution of the aerosol particles, local deposition efficiencies in the human respiratory system were calculated revealing the deposition of soot at alveolar level. The results showed that on average 42% of coarse particles are deposited at the extrathoracic level, whereas 24% are deposited at the pulmonary region. The fine fraction showed a deposition rate of approximately 18% for both deposition levels.

  10. Collaboration in air particulate analysis through sharing of regional resources

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Flora L. [Philippine Nuclear Research Institute, Diliman, Quezon (Philippines)

    2003-03-01

    The air pollution research program of the Philippine Nuclear Research Institute is being pursued in support of the 1999 Clean Air Act. This is being undertaken as part of the RCA/IAEA subproject, 'Air Pollution and Its Trends'. Since the PNRI research reactor (PRR-I) has been on extended shut down for the past 18 years, the PNRI depends solely on X-ray Fluorescence (XRF) spectrometry for elemental characterization of air particulate samples. NAA is a powerful and efficient tool in air particulate characterization and is used in many national programs in the region. Collaboration in air pollution studies through exchange of samples between XRF and NAA groups will widen the range of elements that could be detected by one group. In the RCA/IAEA RAS/4/020, 'Improvement of Research Reactor Operation and Utilization' sharing of research reactor facilities is encouraged. Working out of mechanisms for such sharing will be advantageous to research groups without operational research reactors. This could take the form of exchange of samples or fellowship at a regional host institution. This will allow training of technical staff from countries without research reactors, thus ensuring continuing expertise in NAA even after long periods of reactor shutdown. (author)

  11. Composition and oxidation state of sulfur in atmospheric particulate matter

    Directory of Open Access Journals (Sweden)

    A. F. Longo

    2016-10-01

    Full Text Available The chemical and physical speciation of atmospheric sulfur was investigated in ambient aerosol samples using a combination of sulfur near-edge x-ray fluorescence spectroscopy (S-NEXFS and X-ray fluorescence (XRF microscopy. These techniques were used to determine the composition and oxidation state of sulfur in common primary emission sources and ambient particulate matter collected from the greater Atlanta area. Ambient particulate matter samples contained two oxidation states: S0 and S+VI. Ninety-five percent of the individual aerosol particles (> 1 µm analyzed contain S0. Linear combination fitting revealed that S+VI in ambient aerosol was dominated by ammonium sulfate as well as metal sulfates. The finding of metal sulfates provides further evidence for acidic reactions that solubilize metals, such as iron, during atmospheric transport. Emission sources, including biomass burning, coal fly ash, gasoline, diesel, volcanic ash, and aerosolized Atlanta soil, and the commercially available bacterium Bacillus subtilis, contained only S+VI. A commercially available Azotobacter vinelandii sample contained approximately equal proportions of S0 and S+VI. S0 in individual aerosol particles most likely originates from primary emission sources, such as aerosolized bacteria or incomplete combustion.

  12. Urban particulate matter pollution: a tale of five cities.

    Science.gov (United States)

    Pandis, Spyros N; Skyllakou, Ksakousti; Florou, Kalliopi; Kostenidou, Evangelia; Kaltsonoudis, Christos; Hasa, Erion; Presto, Albert A

    2016-07-18

    Five case studies (Athens and Paris in Europe, Pittsburgh and Los Angeles in the United States, and Mexico City in Central America) are used to gain insights into the changing levels, sources, and role of atmospheric chemical processes in air quality in large urban areas as they develop technologically. Fine particulate matter is the focus of our analysis. In all cases reductions of emissions by industrial and transportation sources have resulted in significant improvements in air quality during the last few decades. However, these changes have resulted in the increasing importance of secondary particulate matter (PM) which dominates over primary in most cases. At the same time, long range transport of secondary PM from sources located hundreds of kilometres from the cities is becoming a bigger contributor to the urban PM levels in all seasons. "Non-traditional" sources including cooking, and residential and agricultural biomass burning contribute an increasing fraction of the now reduced fine PM levels. Atmospheric chemistry is found to change the chemical signatures of a number of these sources relatively fast both during the day and night, complicating the corresponding source apportionment.

  13. Particulate emission factor: A case study of a palm oil mill boiler

    International Nuclear Information System (INIS)

    Chong, W.C.; Rashid, M.; Ramli, M.; Zainura, Z.N.; NorRuwaida, J.

    2010-01-01

    A study to investigate the particulate emission from a boiler of a palm oil mill plant equipped with a multi-cyclones particulate arrest or was performed and reported in this paper. The particulate emission concentration was measured at the outlet of a 8 mt/ hr capacity water-tube typed boiler of a palm oil mill plant processing 27mt/ hr of fresh fruit bunch (FFB). The particulate sample was collected iso-kinetically using the USEPA method 5 sampling train through a sampling port made at the duct of the exiting flue gas between the boiler and a multi-cyclones unit. Results showed that the particulate emission rates exiting the boiler varied from 0.09 to 0.60 g/s with an average of 0.29 + 0.18 g/ s. While the average particulate emission concentration exiting the boiler was 12.1 + 7.36 g/ Nm 3 (corrected to 7 % oxygen concentration), ranging from 3.62 to 25.3 g/ Nm 3 (at 7 % O 2 ) of the flue gas during the measurement. Based on the 27 mt/ hr FFB processed and the capacity of the boiler of 8mt steam/ hr, the calculated particulate emission factor was 39 g particulate/ mt FFB processed or 131 g particulate/ mt boiler capacity, respectively. In addition, based on the finding and in order to comply with the emission limits of 0.4 g/ Nm 3 , the collection efficiency of any given particulate emission pollution control system to consider for the mill will be from 87 to 98 %, which is not easily achievable with the existing multi-cyclones unit. A considerable amount of efforts are still needed pertaining to the particulate emission control problem in the industry. (author)

  14. Characterization of particulate emissions from Australian open-cut coal mines: Toward improved emission estimates.

    Science.gov (United States)

    Richardson, Claire; Rutherford, Shannon; Agranovski, Igor

    2018-06-01

    Given the significance of mining as a source of particulates, accurate characterization of emissions is important for the development of appropriate emission estimation techniques for use in modeling predictions and to inform regulatory decisions. The currently available emission estimation methods for Australian open-cut coal mines relate primarily to total suspended particulates and PM 10 (particulate matter with an aerodynamic diameter available relating to the PM 2.5 (currently available emission estimation techniques, this paper presents results of sampling completed at three open-cut coal mines in Australia. The monitoring data demonstrate that the particulate size fraction varies for different mining activities, and that the region in which the mine is located influences the characteristics of the particulates emitted to the atmosphere. The proportion of fine particulates in the sample increased with distance from the source, with the coarse fraction being a more significant proportion of total suspended particulates close to the source of emissions. In terms of particulate composition, the results demonstrate that the particulate emissions are predominantly sourced from naturally occurring geological material, and coal comprises less than 13% of the overall emissions. The size fractionation exhibited by the sampling data sets is similar to that adopted in current Australian emission estimation methods but differs from the size fractionation presented in the U.S. Environmental Protection Agency methodology. Development of region-specific emission estimation techniques for PM 10 and PM 2.5 from open-cut coal mines is necessary to allow accurate prediction of particulate emissions to inform regulatory decisions and for use in modeling predictions. Development of region-specific emission estimation techniques for PM 10 and PM 2.5 from open-cut coal mines is necessary to allow accurate prediction of particulate emissions to inform regulatory decisions and for

  15. Evaluation of city buses installed diesel particulate filter systems on fleet test; Diesel particulate filter system wo tosaishita rosen bus no soko chosa

    Energy Technology Data Exchange (ETDEWEB)

    Sudo, H [Japan Automobile Research Institute Inc., Tsukuba (Japan)

    1997-10-01

    An environmental air quality of suspended particulate matter is insufficient in the big city area. To reduce the particulate matter, improvement of engine and development of the Diesel Particulate Filter (DPF) system are carrying. The purpose of this report is to investigate a possibility of practical use of the city buses installed DPF systems. From March 1995, investigation for practical use of these DPF systems on a route buses was carried in regular service operation of the Tokyo and Yokohama Transportation Bureau. The investigation items are service situation, smoke density and preparation inspection. From the result for 2 years service operation, each DPF systems needed some failure correspondence. but these were not fatal problem on using the DPF system. Then the subject of relative to durability and reliability became clear, and the performance of a low particulate emission DPF system obtained the high value evaluation for users. 9 refs., 4 figs., 2 tabs.

  16. Impacts d’un changement de politiques énergétiques sur les exploitations irriguées : éclairage sur la base d’un échantillon d’exploitations dans le Saiss (Maroc

    Directory of Open Access Journals (Sweden)

    Imane Rais

    2016-10-01

    Full Text Available Au Maroc, le gaz butane est fortement subventionné pour son usage domestique, et est devenu depuis une dizaine d’années une des sources principales d’énergie utilisées pour le pompage de l’eau souterraine dans les exploitations agricoles. Du fait de son coût élevé pour les finances publiques, il est envisagé un arrêt de cette subvention, couplé à une éventuelle subvention à l’investissement en énergie solaire. La présente étude analyse l’impact de scénarios d’évolutions des politiques énergétiques nationales sur des exploitations irrigantes. Ces évolutions possibles de type d’énergie utilisé sont analysées à la fois en termes de rentabilité et selon le point de vue de l’exploitant lui-même. Un ensemble de 18 exploitations, utilisant 4 différents types d’énergie (gasoil, butane, électrique, photovoltaïque, ont été enquêtées dans la plaine du Saiss. Trois scénarios ont été établis : 1 un arrêt de la subvention au butane ; 2 un arrêt de la subvention couplé à une subvention à l’investissement dans l’énergie solaire ; et 3 un arrêt de la subvention butane couplé à une subvention à l’investissement dans l’énergie électrique. Les résultats montrent que, en cas d’arrêt de la subvention sur le butane, la moitié des exploitants utilisant le butane lors de l’étude envisagent de revenir au gasoil. En cas de subvention de 50% des coûts d’installation de l’énergie photovoltaïque, trois quarts des agriculteurs utilisant le butane ou le gasoil changeraient de système. Seule la moitié des exploitations en butane ou gasoil serait intéressée par un passage à l’électrique, même dans le cas d’une forte subvention à l’investissement. La transition vers le photovoltaïque, préférée par les agriculteurs utilisant le butane ou le gasoil, ne sera pas cependant qu’une question de taux de subvention, du fait notamment d’un fort besoin d’appui technique pour

  17. Le diagnostic anténatal de la trisomie 21 par l'hybridation in situ en fluorescence (FISH): à propos des premiers tests réalisés au Maroc

    Science.gov (United States)

    Lamzouri, Afaf; Natiq, Abdelhafid; Tajir, Mariam; Sendid, Mohamed; Sefiani, Abdelaziz

    2012-01-01

    Introduction Le but de cette étude était de présenter les premiers résultats de diagnostic anténatal de la trisomie 21 par la technique d'hybridation in situ en fluorescence (FISH) au Maroc et discuter son intérêt dans le diagnostic rapide de cette aneuploïdie. Méthodes Ce travail a été réalisé chez 23 femmes avec des grossesses à haut risque de trisomie 21. La moyenne d’âge des gestantes étaient de 37,43 ans avec des extrêmes de 21 et 43 ans. Toutes étaient musulmanes mariées, mariage légitimé par la Charia, dont trois mariages consanguins, sauf une originaire de la République Démocratique du Congo qui était chrétienne et concubine. La majorité des femmes étaient fonctionnaires et avaient un niveau de scolarisation moyen à élevé. Toutes les patientes ont bénéficié d'une consultation de génétique médicale au cours de laquelle il leur a été donné des informations sur la technique, son intérêt et ses limites. Il s'agit de femmes enceintes qui avaient soit un âge maternel élevé ou des signes d'appel échographiques et/ ou biochimiques. Une des patientes était porteuse d'une translocation robertsonienne t(14;21) équilibrée. Une amniocentèse a été réalisée chez toutes les gestantes et aucun avortement n'a était induit par ce geste invasif. L’âge gestationnel moyen à la première consultation était de 14 semaines d'aménorrhée (SA) et à l'amniocentèse était de 16 SA et 5 jours. L'analyse FISH a été réalisée, après consentement des couples, sur des cellules non cultivées à partir des échantillons de liquides amniotiques, en utilisant des sondes spécifiques du chromosome 21. Résultats Parmi les 23 patientes qui ont bénéficiées d'un diagnostic anténatal de la trisomie 21 par la technique FISH, nous avons pu rassurer 21 d'entre elles, et nous avons détecté deux cas de trisomie 21 fœtal. Conclusion La technique FISH permet un diagnostic anténatal rapide, en moins de 48h, de la trisomie 21 sur

  18. Épidémiologie des accidents domestiques graves de l'enfant admis en réanimation pédiatrique polyvalente à l'hôpital d'enfants de Rabat-Maroc

    Science.gov (United States)

    Rafai, Mostafa; Mekaoui, Nour; Chouaib, Naoufal; Bakkali, Hicham; Belyamani, Lahcen; El Koraichi, Alae; El Kettani, Salma Ech-Cherif

    2015-01-01

    Introduction Les accidents domestiques de l'enfant représentent un vrai problème de santé publique dans les pays industrialisés. Au Maroc, la priorité en santé publique est toujours donnée aux pathologies infectieuses, et bien qu'elle soit très peu décrite, la pathologie accidentelle de l'enfant devient de plus en plus fréquente dans notre pays avec une mortalité importante. L'objectif est de mettre le point sur la prévalence, la gravité, les aspects étiologiques, les facteurs de risque et les circonstances de survenue de ces accidents, ainsi que les moyens de prévention active et passive. Méthodes Enquête rétrospective descriptive sur une période de douze mois portant sur tous les enfants pris en charge pour accident domestique grave au service de réanimation pédiatrique polyvalente de l'hôpital universitaire d'enfants de Rabat. Résultats Parmi 698 admissions, 108 cas d'accidents domestiques graves ont étaient colligés (soit 15,5%), L’âge moyen des enfants était de 04ans tout accident confondu, avec un sex-ratio de 1,08 en faveur des garçons. L’évolution générale était marquée par le décès de 16 enfants (soit 14,8%) parmi 164 décès toute pathologie confondue au cours de la même période d’étude (soit 9,75% des décès) avec une durée moyenne d'hospitalisation de 04jours. les brûlures constituaient le premier accident dans notre série par 37cas, et elles étaient la première cause de mortalité par huit cas; par ailleurs, la population la plus à risque de brûlure était les nourrissons (67,6%). L'inhalation intrabronchique d’épingle à foulard (accident particulier dans notre contexte islamique) à été retrouvée chez six cas. Conclusion Les accidents domestiques de l'enfant constituent rarement une préoccupation de premier plan dans la population alors qu'ils sont parfois très graves et source d'une mortalité importante. Le meilleur traitement reste la prévention active et passive. PMID:26015848

  19. Particulate matter regulation for two-stroke two wheelers: necessity or haphazard legislation?

    NARCIS (Netherlands)

    Rijkeboer, R.C.; Bremmers, D.A.C.M.; Samaras, Z.; Ntziachristos, L.

    2005-01-01

    Although interest in particulate emissions has increased considerably during recent years, the subject of particulate matter (PM) emissions from small two-stroke engines used in road vehicles is still largely unexplored. This paper presents the results of an investigation, which examined the typical

  20. Hazard identification of particulate matter on vasomotor dysfunction and progression of atherosclerosis

    DEFF Research Database (Denmark)

    Møller, Peter; Mikkelsen, Lone; Vesterdal, Lise Kristine

    2011-01-01

    and inflammatory pathways. We have assessed the effect of exposure to particulate matter on progression of atherosclerosis and vasomotor function in humans, animals, and ex vivo experimental systems. The type of particles that have been tested in these systems encompass TiO(2), carbon black, fullerene C(60...... of particulate matter....

  1. Biomonitoring of toxic compounds of airborne particulate matter in urban and industriel areas

    DEFF Research Database (Denmark)

    Klumpp, Andreas; Ro-Poulsen, Helge

    2010-01-01

    The toxicity and ecotoxicity of airborne particulate matter is determined by its physical features, but also by its chemical composition. The standardised exposure of accumulative bioindicator plants is suggested as an efficient and reliable tool to assess and monitor effects of particulate matter...

  2. Influence of Channel Geomorphology on Retention of Dissolved and Particulate Matter in a Cascade Mountain Stream

    Science.gov (United States)

    Gary A. Lamberti; Stan V. Gregory; Linda R. Ashkenas; Randall C. Wildman; Alan G. Steinman

    1989-01-01

    Retention of particulate and dissolved nutrients in streams is a major determinant of food avail-ability to stream biota. Retention of particulate matter (leaves) and dissolved nutrients (nitrogen) was studied experimentally during summer 1987 in four 300-500 m reaches of Lookout Creek, a fifth-order stream in the Cascade Mountains of Oregon. Constrained (narrow valley...

  3. Estimates of Particulate Mass for an MCO Containing Mark 1A Fuel

    International Nuclear Information System (INIS)

    WYMAN, H.A.

    1999-01-01

    High, best estimate, and low values are given for particulate inventories within an MCO basket containing freshly cleaned Mark 1A fuel. The findings are compared with the estimates of particulate inventories for an MCO basket containing freshly cleaned Mark IV fuel

  4. Battery condenser system particulate emission factors for cotton gins: Particle size distribution characteristics

    Science.gov (United States)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  5. Nature’s Particulate Matter with and without Charge and Travelling

    NARCIS (Netherlands)

    Ursem, W.N.J.

    2016-01-01

    Natures and anthropogenic particulates can travel long distances on wind flows, but negative electrical charge due to friction can increase dispersion. Models for calculations of distance travelling of biological particulate matter with and without charge are never been calculated in a theoretical

  6. Report Task 2.3: Particulate waste and turbidity in (marine) RAS

    NARCIS (Netherlands)

    Kals, J.; Schram, E.; Brummelhuis, E.B.M.; Bakel, van B.

    2006-01-01

    Particulate waste management and removal is one of the most problematic parts of recirculation aquaculture systems (RAS). Particulate waste and thereby turbidity originates from three major sources: fish (faeces), feed and biofilm (heterotrophic bacteria and fungi). Based on size and density there

  7. Characterization of urban particulate matter by diffusive gradients in thin film technique

    Czech Academy of Sciences Publication Activity Database

    Dufka, Michaela; Dočekal, Bohumil

    (2018), s. 1-8, č. článku 9698710. ISSN 2090-8865 R&D Projects: GA ČR GAP503/10/2002 Institutional support: RVO:68081715 Keywords : thin film technique * urban particulate matter * particulate air pollution Subject RIV: CB - Analytical Chemistry , Separation OBOR OECD: Analytical chemistry Impact factor: 1.801, year: 2016

  8. Origin and biochemical cycling of particulate nitrogen in the Mandovi estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, L

    for particulate organic carbon (POC) and particulate organic nitrogen (PON), delta sup(13) C sub(POC), total hydrolysable amino acid enantiomers (L- and D- amino acids) concentration and composition. Delta sup(13)C sub(POC) values were depleted (-32 to -25 ppt...

  9. GENETIC INFLUENCES ON IN VTIRO PARTICULATE MATTER-INDUCED AIRWAY EPITHELIAL INJURY AND INFLAMMATORY MEDIATOR RELEASE

    Science.gov (United States)

    GENETIC INFLUENCES ON IN VITRO PARTICULATE MATTER-INDUCED AIRWAY EPITHELIAL INJURY AND INFLAMMATORY MEDIATOR RELEASE. JA Dye, JH Richards, DA Andrews, UP Kodavanti. US EPA, RTP, NC, USA.Particulate matter (PM) air pollution is capable of damaging the airway epitheli...

  10. Characterization of urban particulate matter by diffusive gradients in thin film technique

    Czech Academy of Sciences Publication Activity Database

    Dufka, Michaela; Dočekal, Bohumil

    (2018), s. 1-8, č. článku 9698710. ISSN 2090-8865 R&D Projects: GA ČR GAP503/10/2002 Institutional support: RVO:68081715 Keywords : thin film technique * urban particulate matter * particulate air pollution Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 1.801, year: 2016

  11. The role of riverine particulate material on the global cycles of the elements

    International Nuclear Information System (INIS)

    Oelkers, Eric H.; Gislason, Sigurdur R.; Eiriksdottir, Eydis Salome; Jones, Morgan; Pearce, Christopher R.; Jeandel, Catherine

    2011-01-01

    Highlights: → Particulate transport dominates dissolved transport of the elements to the ocean. → Particulate material readily dissolves in sea water releasing its elements. → Particulate element release can rapidly affect the isotopic composition of seawater. → Ocean Nd, Fe, Si, and Sr isotopic ratios are likely affected strongly by this process. - Abstract: A review of the relative masses of continental weathering products transported to the oceans indicates that particulate fluxes dominate dissolved fluxes for most elements. The degree to which this particulate material plays a role in the compositional evolution of seawater depends on its dissolution rate, which appears to be rapid due to its high surface area. Consideration of the results of batch experiments and mineral saturation state calculations suggest that much of the mass dissolved into seawater from particulate material dissolution is rapidly removed by the precipitation of secondary minerals. Although this process limits the degree to which the overall concentration of elements in seawater are affected by the addition of particulate material, the dissolution of isotopically distinct particulate phases may affect the isotopic composition of seawater over remarkably short timescales.

  12. Distribution of particulate carbohydrate in the eastern Arabian sea along 15 (degrees) N

    Digital Repository Service at National Institute of Oceanography (India)

    Nandakumar, K.; Bhosle, N.B.; Wagh, A.B.

    The concentration of particulate carbohydrate varied from 38-158 mu g.l-1 and 19-239 mu g.l-1 in shelf and slope waters respectively. At 10 m water column the concentration of particulate carbohydrate increased with the distance from the shore...

  13. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Gas meter or flow instrumentation... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement. (a) Sampling for particulate emissions requires the use of gas meters or flow instrumentation to...

  14. The Particulate Nature of Matter in Science Education and in Science.

    Science.gov (United States)

    Vos, Wobbe de; Verdonk, Adri H.

    1996-01-01

    Discusses ideas about the particulate nature of matter and assesses the extent to which these represent a compromise between scientific and educational considerations. Analyzes relations between the particulate nature of matter in science and science education in an attempt to understand children's inclination to attribute all kinds of macroscopic…

  15. Distribution of lead-210 and polonium-210 between soluble and particulate phases in seawater

    International Nuclear Information System (INIS)

    Spencer, D.W.

    1975-01-01

    Results are reported from radiometric measurements of the distribution of 210 Pb and 210 Po in surface seawater and suspended particulate matter. Samples of plankton and sediments collected from some locations were also analyzed. Samples of seawater and suspended particulate matter were collected from stations located in the Gulf of Maine, the North Atlantic, and approximately 500 miles southwest of Gilbraltar. (U.S.)

  16. Development of Problem Sets for K-12 and Engineering on Pharmaceutical Particulate Systems

    Science.gov (United States)

    Savelski, Mariano J.; Slater, C. Stewart; Del Vecchio, Christopher A.; Kosteleski, Adrian J.; Wilson, Sarah A.

    2010-01-01

    Educational problem sets have been developed on structured organic particulate systems (SOPS) used in pharmaceutical technology. The sets present topics such as particle properties and powder flow and can be integrated into K-12 and college-level curricula. The materials educate students in specific areas of pharmaceutical particulate processing,…

  17. Coolability of oxidized particulate debris bed accumulated in horizontal narrow gaps

    International Nuclear Information System (INIS)

    Arai, Y.; Sugiyama, K.; Narabayashi, T.

    2007-01-01

    When LOCA occurs in a nuclear reactor system, the coolability of the core would be kept as reported at a series of presentations in ICONE14. Therefore the probability of the core meltdown is negligible small. However, from the view point of defense in depth, it is necessary to be sure that the coolability of the bottom of reactor pressure vessel (RPV) is maintained even if a part of the core should melt and a substantial amount of debris should be deposited on the lower plenum. We carried out an experimental study in order to observe the coolability of particulate core-metal debris bed with 12 mm thickness accompanied with rapid heat generation because of oxidization, which was reported at ICONE14. The coolability was assured by a small amount of coolant supply because of high capillary force of oxidized fine particulate debris produced. In the present study, we examined the coolability of particulate debris bed deposited in narrower gap of 1 mm or 5 mm that coolant supply is hard. The particulate debris beds were piled up on the stainless steel sheet with 0.1 mm thickness, which was used to measure the bottom temperatures of particulate debris bed by using a thermo-video camera. We set up a heat supply section with heat input of 2.1 kW, which simulates the hard debris bed deposited on the particulate debris bed as reported for the TMI-2 accident. We measured the temperatures of the bottom surface of the heat supply section and the heat fluxes released into debris bed as well as the temperatures at the bottom of debris bed on the stainless steel sheet. It is found that when only the upper surface of particulate debris bed is in the film boiling, capillary force causes coolant supply to the particulate debris bed. Therefore, in the condition of thicker gap with small particulate debris, coolability of debris bed is improved. We find out that smaller particulate debris is moved by vapor movement. As a result, the area that high capillary force is caused because of

  18. Final report for measurement of primary particulate matter emissions from light-duty motor vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Norbeck, J. M.; Durbin, T. D.; Truex, T. J.

    1998-12-31

    This report describes the results of a particulate emissions study conducted at the University of California, Riverside, College of Engineering-Center for Environmental Research and Technology (CE-CERT) from September of 1996 to August of 1997. The goal of this program was to expand the database of particulate emissions measurements from motor vehicles to include larger numbers of representative in-use vehicles. This work was co-sponsored by the Coordinating Research Council (CRC), the South Coast Air Quality Management District (SCAQMD), and the National Renewable Energy Laboratory (NREL) and was part of a larger study of particulate emissions being conducted in several states under sponsorship by CRC. For this work, FTP particulate mass emission rates were determined for gasoline and diesel vehicles, along with the fractions of particulates below 2.5 and 10 microns aerodynamic diameter. A total of 129 gasoline-fueled vehicles and 19 diesel-fueled vehicles were tested as part of the program.

  19. Investigations on Mechanical Behaviour of Micro Graphite Particulates Reinforced Al-7Si Alloy Composites

    Science.gov (United States)

    Nagaraj, N.; Mahendra, K. V.; Nagaral, Madeva

    2018-02-01

    Micro particulates reinforced metal matrix composites are finding wide range of applications in automotive and sports equipment manufacturing industries. In the present study, an attempt has been made to develop Al-7Si-micro graphite particulates reinforced composites by using liquid melt method. 3 and 6 wt. % of micro graphite particulates were added to the Al-7Si base matrix. Microstructural characterization was done by using scanning electron microscope and energy dispersive spectroscope. Mechanical behaviour of Al-7Si-3 and 6 wt. % composites were evaluated as per ASTM standards. Scanning electron micrographs revealed the uniform distribution of micro graphite particulates in the Al-7Si alloy matrix. EDS analysis confirmed the presence of B and C elements in graphite reinforced composites. Further, it was noted that ultimate tensile and yield strength of Al-7Si alloy increased with the addition of 3 and 6wt. % of graphite particulates. Hardness of graphite reinforced composites was lesser than the base matrix.

  20. Charging and absorption characteristics of small particulates under alternative and electrostatic voltages in an electrostatic precipitator

    International Nuclear Information System (INIS)

    Jiang Xue-Dong; Xu He; Wang Xin

    2014-01-01

    The charge quantity of small particulates such as PM2.5 plays a key role in the collection efficiency of an electrostatic precipitator (ESP). Under a single electrostatic voltage, it is difficult to charge and absorb small particulates. A new method of superimposing an alternative voltage on the electrostatic voltage is provided in this paper. Characteristics of small particulates are analyzed under alternative and electrostatic voltages. It is demonstrated that an alternative voltage can significantly improve the collection efficiency in three aspects: preventing anti-corona, increasing the charge quantity of small particulates, and increasing the median particulate size by electric agglomeration. In addition, practical usage with the superposition of alternative voltage is provided, and the results are in agreement with the theoretical analysis. (physics of gases, plasmas, and electric discharges)

  1. Status of Suspended Particulate Matters Pollution at Traditional Markets in Makassar City

    Science.gov (United States)

    Suryani, Sri; Fahrunnisa

    2018-03-01

    Research on the status of suspended particulate matters pollution in four traditional markets located in Makassar city has been done. The purpose of this research is to know the air quality in the traditional market areas, especially caused by suspended particulate matters. The background of this research is because traders who trade in traditional markets generally peddle their goods along dusty roads and suspended particulate matters in dust can be inhaled when the vehicle passes. These suspended particulate matters pollutant can cause lung diseases. The results showed that the level of suspended particulate matters pollution fluctuates every year depending on the local wind speed, humidity, and temperature. Research results also showed the values were over the standard value according to the governor of South Sulawesi regulation.

  2. Disease-Associated Particulates and Joint Inflammation; Mechanistic Insights and Potential Therapeutic Targets

    Directory of Open Access Journals (Sweden)

    Olwyn R. Mahon

    2018-05-01

    Full Text Available It is now well established that intra-articular deposition of endogenous particulates, such as osteoarthritis-associated basic calcium phosphate crystals, gout-associated monosodium urate crystals, and calcium deposition disease-associated calcium pyrophosphate crystals, contributes to joint destruction through the production of cartilage-degrading enzymes and pro-inflammatory cytokines. Furthermore, exogenous wear-debris particles, generated from prosthetic implants, drive periprosthetic osteolysis which impacts on the longevity of total joint replacements. Over the last few years, significant insight has been gained into the mechanisms through which these particulates exert their effects. Not only has this increased our understanding of the pathological processes associated with crystal deposition but it has also led to the identification of a number of therapeutic targets to treat particulate-associated disease. In this review, we discuss recent developments regarding the cellular events triggered by joint-associated particulates, as well as future directions in therapy for particulate-related arthropathies.

  3. Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events.

    Science.gov (United States)

    Bhadha, Jehangir H; Sexton, Anne; Lang, Timothy A; Daroub, Samira H

    2017-11-07

    The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the overall P loads in drainage water. A settling tank experiment was conducted to capture suspended particulates during discrete drainage events. Farm canal discharge water was collected in a series of two 200 L settling tanks over the entire duration of the drainage event, so as to represent a composite subsample of the water being discharged. Imhoff settling cones are ultimately used to settle out the suspended particulates. This is achieved by siphoning water from the settling tanks via the cones. The particulates are then collected for physico-chemical analyses.

  4. Health effects of particulate air pollution and airborne desert dust

    Science.gov (United States)

    Lelieveld, J.; Pozzer, A.; Giannadaki, D.; Fnais, M.

    2013-12-01

    Air pollution by fine particulate matter (PM2.5) has increased strongly with industrialization and urbanization. In the past decades this increase has taken place at a particularly high pace in South and East Asia. We estimate the premature mortality and the years of human life lost (YLL) caused by anthropogenic PM2.5 and airborne desert dust (DU2.5) on regional and national scales (Giannadaki et al., 2013; Lelieveld et al., 2013). This is based on high-resolution global model calculations that resolve urban and industrial regions in relatively great detail. We apply an epidemiological health impact function and find that especially in large countries with extensive suburban and rural populations, air pollution-induced mortality rates have been underestimated given that previous studies largely focused on the urban environment. We calculate a global premature mortality by anthropogenic aerosols of 2.2 million/year (YLL ≈ 16 million/year) due to lung cancer and cardiopulmonary disease. High mortality rates by PM2.5 are found in China, India, Bangladesh, Pakistan and Indonesia. Desert dust DU2.5 aerosols add about 0.4 million/year (YLL ≈ 3.6 million/year). Particularly significant mortality rates by DU2.5 occur in Pakistan, China and India. The estimated global mean per capita mortality caused by airborne particulates is about 0.1%/year (about two thirds of that caused by tobacco smoking). We show that the highest premature mortality rates are found in the Southeast Asia and Western Pacific regions (about 25% and 46% of the global rate, respectively) where more than a dozen of the most highly polluted megacities are located. References: Giannadaki, D., A. Pozzer, and J. Lelieveld, Modeled global effects of airborne desert dust on air quality and premature mortality, Atmos. Chem. Phys. Discuss. (submitted), 2013. Lelieveld, J., C. Barlas, D. Giannadaki, and A. Pozzer, Model calculated global, regional and megacity premature mortality due to air pollution by ozone

  5. Factors influencing particulate lipid production in the East Atlantic Ocean

    Science.gov (United States)

    Gašparović, B.; Frka, S.; Koch, B. P.; Zhu, Z. Y.; Bracher, A.; Lechtenfeld, O. J.; Neogi, S. B.; Lara, R. J.; Kattner, G.

    2014-07-01

    Extensive analyses of particulate lipids and lipid classes were conducted to gain insight into lipid production and related factors along the biogeochemical provinces of the Eastern Atlantic Ocean. Data are supported by particulate organic carbon (POC), chlorophyll a (Chl a), phaeopigments, Chl a concentrations and carbon content of eukaryotic micro-, nano- and picophytoplankton, including cell abundances for the latter two and for cyanobacteria and prokaryotic heterotrophs. We focused on the productive ocean surface (2 m depth and deep Chl a maximum (DCM). Samples from the deep ocean provided information about the relative reactivity and preservation potential of particular lipid classes. Surface and DCM particulate lipid concentrations (3.5-29.4 μg L-1) were higher than in samples from deep waters (3.2-9.3 μg L-1) where an increased contribution to the POC pool was observed. The highest lipid concentrations were measured in high latitude temperate waters and in the North Atlantic Tropical Gyral Province (13-25°N). Factors responsible for the enhanced lipid synthesis in the eastern Atlantic appeared to be phytoplankton size (micro, nano, pico) and the low nutrient status with microphytoplankton having the most expressed influence in the surface and eukaryotic nano- and picophytoplankton in the DCM layer. Higher lipid to Chl a ratios suggest enhanced lipid biosynthesis in the nutrient poorer regions. The various lipid classes pointed to possible mechanisms of phytoplankton adaptation to the nutritional conditions. Thus, it is likely that adaptation comprises the replacement of membrane phospholipids by non-phosphorus containing glycolipids under low phosphorus conditions. The qualitative and quantitative lipid compositions revealed that phospholipids were the most degradable lipids, and their occurrence decreased with increasing depth. In contrast, wax esters, possibly originating from zooplankton, survived downward transport probably due to the fast sinking

  6. Development of Test Protocols for International Space Station Particulate Filters

    Science.gov (United States)

    Vijayakumar, R.; Green, Robert D.; Agui, Juan H.

    2015-01-01

    Air quality control on the International Space Station (ISS) is a vital requirement for maintaining a clean environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of gravitational settling. The ISS Environmental Control and Life Support System (ECLSS) uses a filtration system that has been in use for over 14 years and has proven to meet this challenge. The heart of this system is a traditional High-Efficiency Particulate Air (HEPA) filter configured to interface with the rest of the life support elements and provide effective cabin filtration. The filter element for this system has a non-standard cross-section with a length-to-width ratio (LW) of 6.6. A filter test setup was designed and built to meet industry testing standards. A CFD analysis was performed to initially determine the optimal duct geometry and flow configuration. Both a screen and flow straighter were added to the test duct design to improve flow uniformity and face velocity profiles were subsequently measured to confirm. Flow quality and aerosol mixing assessments show that the duct flow is satisfactory for the intended leak testing. Preliminary leak testing was performed on two different ISS filters, one with known perforations and one with limited use, and results confirmed that the testing methods and photometer instrument are sensitive enough to detect and locate compromised sections of an ISS BFE.Given the engineering constraints in designing spacecraft life support systems, it is anticipated that non-industry standard filters will be required in future designs. This work is focused on developing test protocols for testing the ISS BFE filters, but the methodology is general enough to be extended to other present and future spacecraft filters. These techniques for characterizing the test duct and perform leak testing

  7. Determination of Dibenzacridines in the Particulate Phase of Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Sasaki TA

    2014-12-01

    Full Text Available This study attempted to resolve a controversy related to the presence of dibenz[a,j]acridine and dibenz[a,h]acridine in the particulate phase of cigarette smoke. Smoking was performed using FTC conditions (35 mL puff volume, 2 sec. puff, 1 min. interval on a Borgwaldt RM 20/CS smoking machine. The particulate phase of forty cigarettes was collected on 92 mm Cambridge filter pads. Pads were combined to analyze the particulate phase of the mainstream smoke from between 120 and 320 cigarettes. In an initial scheme of analysis, the pads were extracted with an acidic aqueous solution. This aqueous solution was then washed with CH2Cl2 and the organic phase discarded. The aqueous solution was then changed to basic and extracted with CH2Cl2, which was concentrated and analyzed via GC/MS. The dibenzacridine could not be detected utilizing this scheme, even when the pads had been spiked with a few thousand nanograms of dibenzacridine. After using several other organic solvents (cyclohexane, CHCl3, and benzene to eliminate the possibility that the extraction efficiency of CH2Cl2 was poor, it was determined that dibenzacridine was being discarded with the first CH2Cl2 wash. A successful separation scheme was developed by extracting the smoked pad with an aqueous acidic solution, followed by extraction of the aqueous phase with CH2Cl2without pH change. The CH2Cl2 extract was concentrated under nitrogen and 1 µL injected for GC/MS analysis. Quantification was achieved by spiking the pads with dibenz[a,j]acridine-d13 as an internal standard at a level equal to 1.7-2.5 ng/cig. The limit of detection for this technique was approximately 0.5 ng/cig. The chromatographic separation was performed with a 30 m BPX-5 column (0.25 mm i.d., 0.25 µm film thickness. Mass spectral data were acquired in selected ion monitoring (SIM mode with m/z = 279 for the two dibenzacridine isomers and m/z = 292 for the deuterated internal standard. Three commercial cigarettes were

  8. Airborne particulates. European directives and standardization; Matieres particulaires dans l`air ambiant directives europeennes et normalisation

    Energy Technology Data Exchange (ETDEWEB)

    Houdret, J.L. [Ecole Nationale Superieure des Mines, 59 - Douai (France)

    1996-12-31

    The development of future European directives concerning atmospheric dusts and particulates, organization of the in-charge committee, measurement requirements and limit value determination processes are presented. Various measuring methods and instruments used for particulate and aerosol measurements are reviewed

  9. Source apportionment of PM10 mass and particulate carbon in the Kathmandu Valley, Nepal

    Science.gov (United States)

    Kim, Bong Mann; Park, Jin-Soo; Kim, Sang-Woo; Kim, Hyunjae; Jeon, Haeun; Cho, Chaeyoon; Kim, Ji-Hyoung; Hong, Seungkyu; Rupakheti, Maheswar; Panday, Arnico K.; Park, Rokjin J.; Hong, Jihyung; Yoon, Soon-Chang

    2015-12-01

    The Kathmandu Valley in Nepal is a bowl-shaped urban basin in the Himalayan foothills with a serious problem of fine particulate air pollution that impacts local health and impairs visibility. Particulate carbon concentrations have reached severe levels that threaten the health of 3.5 million local residents. Moreover, snow and ice on the Himalayan mountains are melting as a result of additional warming due to particulate carbon, especially high black carbon concentrations. To date, the sources of the Valley's particulate carbon and the impacts of different sources on particulate carbon concentrations are not well understood. Thus, before an effective control strategy can be developed, these particulate carbon sources must be identified and quantified. Our study has found that the four primary sources of particulate carbon in the Kathmandu Valley during winter are brick kilns, motor vehicles, fugitive soil dust, and biomass/garbage burning. Their source contributions are quantified using a recently developed new multivariate receptor model SMP. In contrast to other highly polluted areas such as China, secondary contribution is almost negligible in Kathmandu Valley. Brick kilns (40%), motor vehicles (37%) and biomass/garbage burning (22%) have been identified as the major sources of elemental carbon (black carbon) in the Kathmandu Valley during winter, while motor vehicles (47%), biomass/garbage burning (32%), and soil dust (13%) have been identified as the most important sources of organic carbon. Our research indicates that controlling emissions from motor vehicles, brick kilns, biomass/garbage burning, and soil dust is essential for the mitigation of the particulate carbon that threatens public health, impairs visibility, and influences climate warming within and downwind from the Kathmandu Valley. In addition, this paper suggests several useful particulate carbon mitigation methods that can be applied to Kathmandu Valley and other areas in South Asia with

  10. Fine particulate matter in acute exacerbation of COPD

    Directory of Open Access Journals (Sweden)

    Lei eNi

    2015-10-01

    Full Text Available Chronic obstructive pulmonary disease (COPD is a common airway disorder. In particular, acute exacerbations of COPD (AECOPD can significantly reduce pulmonary function. The majority of AECOPD episodes are attributed to infections, although environmental stress also plays a role. Increasing urbanization and associated air pollution, especially in developing countries, have been shown to contribute to COPD pathogenesis. Elevated levels of particulate matter (PM in polluted air are strongly correlated with the onset and development of various respiratory diseases. In this review, we have conducted an extensive literature search of recent studies of the role of PM2.5 (fine PM in AECOPD. PM2.5 leads to AECOPD via inflammation, oxidative stress, immune dysfunction, and altered airway epithelial structure and microbiome. Reducing PM2.5 levels is a viable approach to lower AECOPD incidence, attenuate COPD progression and decrease the associated healthcare burden.

  11. Characterization of coarse particulate matter in school gyms

    Energy Technology Data Exchange (ETDEWEB)

    Branis, Martin, E-mail: branis@natur.cuni.cz [Charles University in Prague, Faculty of Science, Institute for Environmental Studies, Prague (Czech Republic); Safranek, Jiri [Charles University in Prague, Faculty of Physical Education, Department of Outdoor Sports, Prague (Czech Republic)

    2011-05-15

    We investigated the mass concentration, mineral composition and morphology of particles resuspended by children during scheduled physical education in urban, suburban and rural elementary school gyms in Prague (Czech Republic). Cascade impactors were deployed to sample the particulate matter. Two fractions of coarse particulate matter (PM{sub 10-2.5} and PM{sub 2.5-1.0}) were characterized by gravimetry, energy dispersive X-ray spectrometry and scanning electron microscopy. Two indicators of human activity, the number of exercising children and the number of physical education hours, were also recorded. Lower mass concentrations of coarse particulate matter were recorded outdoors (average PM{sub 10-2.5} 4.1-7.4 {mu}g m{sup -3} and PM{sub 2.5-1.0} 2.0-3.3 {mu}g m{sup -3}) than indoors (average PM{sub 10-2.5} 13.6-26.7 {mu}g m{sup -3} and PM{sub 2.5-1.0} 3.7-7.4 {mu}g m{sup -3}). The indoor concentrations of coarse aerosol were elevated during days with scheduled physical education with an average indoor-outdoor (I/O) ratio of 2.5-16.3 for the PM{sub 10-2.5} and 1.4-4.8 for the PM{sub 2.5-1.0} values. Under extreme conditions, the I/O ratios reached 180 (PM{sub 10-2.5}) and 19.1 (PM{sub 2.5-1.0}). The multiple regression analysis based on the number of students and outdoor coarse PM as independent variables showed that the main predictor of the indoor coarse PM concentrations is the number of students in the gym. The effect of outdoor coarse PM was weak and inconsistent. The regression models for the three schools explained 60-70% of the particular dataset variability. X-ray spectrometry revealed 6 main groups of minerals contributing to resuspended indoor dust. The most abundant particles were those of crustal origin composed of Si, Al, O and Ca. Scanning electron microscopy showed that, in addition to numerous inorganic particles, various types of fibers and particularly skin scales make up the main part of the resuspended dust in the gyms. In conclusion, school

  12. Experimental study of particulate fouling onto heat exchanger elements

    International Nuclear Information System (INIS)

    Chandrasa

    1994-01-01

    An experimental study of particulate fouling onto tubular heat exchanger surfaces was carried out using sodium sulfate particles. An experimental apparatus equipped with an aerosol generator has been used to examine the deposition of small particles under controlled conditions. Two sets of experiments were performed. Firstly, the deposition against time of solid particles onto single heat exchanger tube in cross-flow was studied. The effects of a number variables such as particle size, gas velocity and temperature on the deposition was analysed. Secondly, the deposition for the aerosol particles as they passed through a bank of finned tubes was examined. The deposition patterns on various tubes depended on local conditions (velocity and temperature) within the bank. It was found that the fouling resistance increases as aerosol flow rate decreases. The smaller particles showed higher fouling resistance. (author) [fr

  13. Inhibition of intercellular communication by airborne particulate matter

    Energy Technology Data Exchange (ETDEWEB)

    Heussen, G.A.H. (Landbouwhogeschool Wageningen (Netherlands). Dept. of Toxicology)

    1991-04-01

    To investigate the inhibition of gap junction mediated intercellular communication (IC) by extracts of airborne particulate matter (APM), V79 cells were incubated with extracts of APM and subsequently microinjected with the fluorescent dye Lucifer Yellow, after which the number of fluorescent (= communicating) cells was determined. To compare inhibitory effects on IC with mutagenicity, APM was also tested in the Salmonella microsome assay. Six different extracts were tested, two outdoor extracts representing a heavily polluted and a relatively clean sample, and four indoor extracts, taken either in livingrooms with or without wood combustion in an open fire place, or in a room with or without cigarette smoking. Non-cytotoxic doses of outdoor and indoor APM inhibited IC in V79 cells in dose- and time-dependent manner. Mutagenicity data and IC data were correlated. These results suggest that APM has tumor promoter activity in addition to mutagenic activity. (orig.).

  14. High exhaust temperature, zoned, electrically-heated particulate matter filter

    Science.gov (United States)

    Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima

    2015-09-22

    A system includes a particulate matter (PM) filter, an electric heater, and a control circuit. The electric heater includes multiple zones, which each correspond to longitudinal zones along a length of the PM filter. A first zone includes multiple discontinuous sub-zones. The control circuit determines whether regeneration is needed based on an estimated level of loading of the PM filter and an exhaust flow rate. In response to a determination that regeneration is needed, the control circuit: controls an operating parameter of an engine to increase an exhaust temperature to a first temperature during a first period; after the first period, activates the first zone; deactivates the first zone in response to a minimum filter face temperature being reached; subsequent to deactivating the first zone, activates a second zone; and deactivates the second zone in response to the minimum filter face temperature being reached.

  15. High efficiency particulate removal with sintered metal filters

    International Nuclear Information System (INIS)

    Kirstein, B.E.; Paplawsky, W.J.; Pence, D.T.; Hedahl, T.G.

    1981-01-01

    Because of their particle removal efficiencies and durability, sintered metal filters have been chosen for HEPA filter protection in the off-gas treatment system for the proposed Idaho National Engineering Laboratory Transuranic Waste Treatment Facility. Process evaluation of sintered metal filters indicated a lack of sufficient process design data to assume trouble-free operation. Subsequent pilot-scale testing was performed with fly ash as the test particulate. The test results showed that the sintered metal filters can have an efficiency greater than 0.9999999 for the specific test conditions used. Stable pressure drop characteristics were observed in pulsed and reversed flow blowback modes of operation. Over 4900 hours of operation were obtained with operating conditions ranging up to approximately 90 0 C and 24 volume percent water vapor in the gas stream

  16. First Experiments with the Simulation of Particulate Flows

    Energy Technology Data Exchange (ETDEWEB)

    Uhlmann, M.

    2003-07-01

    Several variants of a Eulerian-Lagrangian method for the simulation of particulate flows are implemented in a finite-difference framework. All methods have in common that they represent the presence of the solid fraction by means of artificial volume forces in the momentum equation of the fluid phase. Thereby, explicit griddling of the moving particles is avoided and a fixed grid can be used. The computations show that the direct forcing method (Kin et a/., 2001) is not adequate for a our purposes due to large oscillations in the hydro-dynamical forces. The immersed method of Pekin (2002) does provide accurate predictions of particle motion,however at the cost of a small time step. (Author) 33 refs.

  17. Direct and quantitative photothermal absorption spectroscopy of individual particulates

    International Nuclear Information System (INIS)

    Tong, Jonathan K.; Hsu, Wei-Chun; Eon Han, Sang; Burg, Brian R.; Chen, Gang; Zheng, Ruiting; Shen, Sheng

    2013-01-01

    Photonic structures can exhibit significant absorption enhancement when an object's length scale is comparable to or smaller than the wavelength of light. This property has enabled photonic structures to be an integral component in many applications such as solar cells, light emitting diodes, and photothermal therapy. To characterize this enhancement at the single particulate level, conventional methods have consisted of indirect or qualitative approaches which are often limited to certain sample types. To overcome these limitations, we used a bilayer cantilever to directly and quantitatively measure the spectral absorption efficiency of a single silicon microwire in the visible wavelength range. We demonstrate an absorption enhancement on a per unit volume basis compared to a thin film, which shows good agreement with Mie theory calculations. This approach offers a quantitative approach for broadband absorption measurements on a wide range of photonic structures of different geometric and material compositions

  18. Sorption of polycyclic aromatic hydrocarbons on particulate organic matters

    International Nuclear Information System (INIS)

    Guo Xueyan; Luo Lei; Ma Yibing; Zhang Shuzhen

    2010-01-01

    Particulate organic matter (POM) is a key organic matter fraction which can influence soil fertility. Its interactions with hydrophobic organic pollutants (HOCs) have not been characterized and the mechanisms of retention of HOCs by POM remain unclear. In the present study, sorption behaviors of polycyclic aromatic hydrocarbons (PAHs) naphthalene (NAP), phenanthrene (PHE), and pyrene (PYR) by POMs separated from different soils were examined and the POMs were characterized by elemental analysis, solid state 13 C NMR, and Fourier transform infrared spectroscopy (FT-IR). The results indicated that POMs were mainly composed of aliphatic components with high polarity. The different original POMs showed similar chemical composition and configuration. Sorption behaviors of PAHs indicated that there was no significant difference in sorption capacity among the POMs. Sorption of NAP and PHE by POMs displayed a nonlinear isotherm, while sorption of PYR yielded a linear isotherm. No significant hysteresis and ionic strength effect were observed for PAH desorption from the POMs.

  19. Particulate and gaseous emissions from residential biomass combustion

    International Nuclear Information System (INIS)

    Boman, Christoffer

    2005-04-01

    Biomass is considered to be a sustainable energy source with significant potentials for replacing electricity and fossil fuels, not at least in the residential sector. However, present wood combustion is a major source of ambient concentrations of hydrocarbons (e.g. VOC and PAH) and particulate matter (PM) and exposure to these pollutants have been associated with adverse health effects. Increased focus on combustion related particulate emissions has been seen concerning the formation, characteristics and implications to human health. Upgraded biomass fuels (e.g. pellets) provide possibilities of more controlled and optimized combustion with less emission of products of incomplete combustion (PICs). For air quality and health impact assessments, regulatory standards and evaluations concerning residential biomass combustion, there is still a need for detailed emission characterization and quantification when using different fuels and combustion techniques. This thesis summarizes the results from seven different papers. The overall objective was to carefully and systematically study the emissions from residential biomass combustion with respect to: i) experimental characterization and quantification, ii) influences of fuel, appliance and operational variables and iii) aspects of ash and trace element transformations and aerosol formation. Special concern in the work was on sampling, quantification and characterization of particulate emissions using different appliances, fuels and operating procedures. An initial review of health effects showed epidemiological evidence of potential adverse effect from wood smoke exposure. A robust whole flow dilution sampling set-up for residential biomass appliances was then designed, constructed and evaluated, and subsequently used in the following emission studies. Extensive quantifications and characterizations of particulate and gases emissions were performed for residential wood and pellet appliances. Emission factor ranges for

  20. Coarse Particulate Organic Matter: Storage, Transport, and Retention

    Energy Technology Data Exchange (ETDEWEB)

    Tiegs, Scott [Oakland University, Rochester, MI; Lamberti, Gary A. [University of Notre Dame, IN; Entrekin, Sally A. [University of Central Arkansas; Griffiths, Natalie A. [ORNL

    2017-08-01

    Coarse particulate organic matter, or CPOM, is a basal energy and nutrient resource in many stream ecosystems and is provided by inputs from the riparian zone, incoming tributaries, and to a lesser extent from in-stream production. The ability of a stream to retain CPOM or slow its transport is critical to its consumption and assimilation by stream biota. In this chapter, we describe basic exercises to measure (1) the amount of CPOM in the streambed and (2) the retention of CPOM from standardized particle releases. We further describe advanced exercises that (1) experimentally enhance the retentiveness of a stream reach and (2) measure organic carbon transport and turnover (i.e., spiraling) in the channel.

  1. Coarse Particulate Organic Matter: Storage, Transport, and Retention

    Energy Technology Data Exchange (ETDEWEB)

    Tiegs, Scott [Oakland University, Rochester, MI; Lamberti, Gary A. [University of Notre Dame, IN; Entrekin, Sally A. [University of Central Arkansas; Griffiths, Natalie A. [ORNL

    2017-06-01

    Coarse particulate organic matter, or CPOM, is a basal energy and nutrient resource in many stream ecosystems and is provided by inputs from the riparian zone, incoming tributaries, and to a lesser extent from in-stream production. The ability of a stream to retain CPOM or slow its transport is critical to its consumption and assimilation by stream biota. In this chapter, we describe basic exercises to measure (1) the amount of CPOM in the streambed and (2) the retention of CPOM from standardized particle releases. We further describe advanced exercises that (1) experimentally enhance the retentiveness of a stream reach and (2) measure organic carbon transport and turnover (i.e., spiraling) in the channel.

  2. Electromagnetic characterization of fine-scale particulate composite materials

    International Nuclear Information System (INIS)

    Talbot, P.; Konn, A.M.; Brosseau, C.

    2002-01-01

    We report the results of the composition and frequency-dependent complex permittivity and permeability of ZnO and γ-Fe 2 O 3 composites prepared by powder pressing. The electromagnetic properties of these materials exhibit a strong dependence on the powder size of the starting materials. In the microwave frequency range, the permittivity and permeability show nonlinear variations with volume fraction of Fe 2 O 3 . As the particle size decreases from a few micrometers to a few tens of nanometers, the data indicate that local mesostructural factors such as shape anisotropy, porosity and possible effect of the binder are likely to be intertwined in the understanding of electromagnetic properties of fine-scale particulate composite materials

  3. Does copepod size determine food consumption of particulate feeding fish?

    DEFF Research Database (Denmark)

    Deurs, Mikael van; Koski, Marja; Rindorf, Anna

    2014-01-01

    on adult particulate feeding fish is unknown. In the present study, we investigated the hypothesis that the availability of the large copepods determines food consumption and growth conditions of lesser sandeel (Ammodytes marinus) in the North Sea. Analysis of stomach content suggested that food...... consumption is higher for fish feeding on large copepods, and additional calculations revealed how handling time limitation may provide part of the explanation for this relationship. Comparing stomach data and zooplankton samples indicated that lesser sandeel actively target large copepods when......The climate-induced reduction in the mean copepod size, mainly driven by a decrease in the abundance of the large Calanus finmarchicus around 1987, has been linked to the low survival of fish larvae in the North Sea. However, to what extent this sort of reduction in copepod size has any influence...

  4. Characterization of coarse particulate matter in school gyms

    International Nuclear Information System (INIS)

    Branis, Martin; Safranek, Jiri

    2011-01-01

    We investigated the mass concentration, mineral composition and morphology of particles resuspended by children during scheduled physical education in urban, suburban and rural elementary school gyms in Prague (Czech Republic). Cascade impactors were deployed to sample the particulate matter. Two fractions of coarse particulate matter (PM 10-2.5 and PM 2.5-1.0 ) were characterized by gravimetry, energy dispersive X-ray spectrometry and scanning electron microscopy. Two indicators of human activity, the number of exercising children and the number of physical education hours, were also recorded. Lower mass concentrations of coarse particulate matter were recorded outdoors (average PM 10-2.5 4.1-7.4 μg m -3 and PM 2.5-1.0 2.0-3.3 μg m -3 ) than indoors (average PM 10-2.5 13.6-26.7 μg m -3 and PM 2.5-1.0 3.7-7.4 μg m -3 ). The indoor concentrations of coarse aerosol were elevated during days with scheduled physical education with an average indoor-outdoor (I/O) ratio of 2.5-16.3 for the PM 10-2.5 and 1.4-4.8 for the PM 2.5-1.0 values. Under extreme conditions, the I/O ratios reached 180 (PM 10-2.5 ) and 19.1 (PM 2.5-1.0 ). The multiple regression analysis based on the number of students and outdoor coarse PM as independent variables showed that the main predictor of the indoor coarse PM concentrations is the number of students in the gym. The effect of outdoor coarse PM was weak and inconsistent. The regression models for the three schools explained 60-70% of the particular dataset variability. X-ray spectrometry revealed 6 main groups of minerals contributing to resuspended indoor dust. The most abundant particles were those of crustal origin composed of Si, Al, O and Ca. Scanning electron microscopy showed that, in addition to numerous inorganic particles, various types of fibers and particularly skin scales make up the main part of the resuspended dust in the gyms. In conclusion, school gyms were found to be indoor microenvironments with high concentrations of

  5. Particulate emissions from a mid-latitude prescribed chaparral fire

    Science.gov (United States)

    Cofer, Wesley R., III; Levine, Joel S.; Sebacher, Daniel I.; Winstead, Edward L.; Riggin, Philip J.; Brass, James A.; Ambrosia, Vincent G.

    1988-01-01

    Particulate emission from a 400-acre prescribed chaparral fire in the San Dimas Experimental Forest was investigated by collecting smoke aerosol on Teflon and glass-fiber filters from a helicopter, and using SEM and EDAX to study the features of the particles. Aerosol particles ranged in size from about 0.1 to 100 microns, with carbon, oxygen, magnesium, aluminum, silicon, calcium, and iron as the primary elements. The results of ion chromatographic analysis of aerosol-particle extracts (in water-methanol) revealed the presence of significant levels of NO2(-), NO3(-), SO4(2-), Cl(-), PO4(3-), C2O4(2-), Na(+), NH4(+), and K(+). The soluble ionic portion of the aerosol was estimated to be about 2 percent by weight.

  6. First Experiments with the Simulation of Particulate Flows

    International Nuclear Information System (INIS)

    Uhlmann, M.

    2003-01-01

    Several variants of a Eulerian-Lagrangian method for the simulation of particulate flows are implemented in a finite-difference framework. All methods have in common that they represent the presence of the solid fraction by means of artificial volume forces in the momentum equation of the fluid phase. Thereby, explicit griddling of the moving particles is avoided and a fixed grid can be used. The computations show that the direct forcing method (Kin et a/., 2001) is not adequate for a our purposes due to large oscillations in the hydro-dynamical forces. The immersed method of Pekin (2002) does provide accurate predictions of particle motion,however at the cost of a small time step. (Author) 33 refs

  7. Dispersion model for airborne radioactive particulates inside a process building

    International Nuclear Information System (INIS)

    Perkins, W.C.; Stoddard, D.H.

    1984-02-01

    An empirical model, predicting the spread of airborne radioactive particles after they are released inside a building, has been developed. The basis for this model is a composite of data for dispersion of airborne activity recorded during 12 case incidents. These incidents occurred at the Savannah River Plant (SRP) during approximately 90 plant-years of experience with the chemical and metallurgical processing of purified neptunium and plutonium. The model illustrates that the multiple-air-zone concept, used in the designs of many nuclear facilities, can be an efficient safety feature to limit the spread of airborne activity from a release. This study also provides some insight into an apparently anomalous behavior of airborne particulates, namely, their migration against the prevailing flow of ventilation air. 2 references, 12 figures, 4 tables

  8. Suspended particulate matter in dwellings - the impact of tobacco smoking

    Energy Technology Data Exchange (ETDEWEB)

    Revsbech, P.; Korsgaard, J.; Lundqvist, G.R.

    1987-01-01

    The indoor concentration of suspended particulate matter (SPM) was measured in 44 retrofitted and tight dwellings, which had electric cooking and were central heated and where the basic ventilation rate in median amounted 0.23 air changes per hour as measured with a tracer dilution method. The indoor concentration of SPM was in medium 230 ..mu..g/m/sup 3/ with a strong correlation to the tobacco consumption (r/sub s/ = 0.716), but with no correlation to the frequency of airing or the basic ventilation rate. Tobacco smoking seems to be the main indoor source of SPM in contemporary dwellings. The importance of these findings is underlined by epidemiologic studies on passive smoking and health. Air quality standards for the ambient air are based on certain risk groups such as infants, children, persons with chronic obstructive lung disorders, and indoor air standards should be based on the same concepts of health protection.

  9. Satellite observation of particulate organic carbon dynamics in ...

    Science.gov (United States)

    Particulate organic carbon (POC) plays an important role in coastal carbon cycling and the formation of hypoxia. Yet, coastal POC dynamics are often poorly understood due to a lack of long-term POC observations and the complexity of coastal hydrodynamic and biogeochemical processes that influence POC sources and sinks. Using field observations and satellite ocean color products, we developed a nw multiple regression algorithm to estimate POC on the Louisiana Continental Shelf (LCS) from satellite observations. The algorithm had reliable performance with mean relative error (MRE) of ?40% and root mean square error (RMSE) of ?50% for MODIS and SeaWiFS images for POC ranging between ?80 and ?1200 mg m23, and showed similar performance for a large estuary (Mobile Bay). Substantial spatiotemporal variability in the satellite-derived POC was observed on the LCS, with high POC found on the inner shelf (satellite data with carefully developed algorithms can greatly increase

  10. Elemental concentration of zooplankton and their particulate products

    International Nuclear Information System (INIS)

    Fowler, S.W.; Oregioni, B.

    1974-01-01

    Since zooplankton fecal pellets and molts are major vectors in the vertical transport of zinc in the sea, analyses have been made also for other trace metals in these particulate products. Euphausiids and pelagic shrimp were collected live off the Monaco coast by taking several short oblique tows with an Issacs-Kidd midwater trawl. Animals were placed in clean sea water, sorted according to species and immediately transported to the laboratory in plastic containers filled with filtered sea water taken at the collection site. Samples of microplankton, which serve as food for the macroplankton were also taken. Elemental concentrations in whole euphausiids and shrimp were measured. It was observed that molt analyses strongly support the contention that crustacean molts play an important role in the transport of metals and radionuclides in marine ecosystems. Molts can release metals to the water column or sediments upon decomposition or serve as a rich source of metals for organisms of other trophic levels which ingest them

  11. Simulation of erosion by a particulate airflow through a ventilator

    Science.gov (United States)

    Ghenaiet, A.

    2015-08-01

    Particulate flows are a serious problem in air ventilation systems, leading to erosion of rotor blades and aerodynamic performance degradation. This paper presents the numerical results of sand particle trajectories and erosion patterns in an axial ventilator and the subsequent blade deterioration. The flow field was solved separately by using the code CFX- TASCflow. The Lagrangian approach for the solid particles tracking implemented in our inhouse code considers particle and eddy interaction, particle size distribution, particle rebounds and near walls effects. The assessment of erosion wear is based on the impact frequency and local values of erosion rate. Particle trajectories and erosion simulation revealed distinctive zones of impacts with high rates of erosion mainly on the blade pressure side, whereas the suction side is eroded around the leading edge.

  12. Particulate matter pollution over a Mediterranean urban area.

    Science.gov (United States)

    Pateraki, St; Assimakopoulos, V D; Maggos, Th; Fameli, K M; Kotroni, V; Vasilakos, Ch

    2013-10-01

    The main purpose of this study is to investigate the aerosols' (PM10, PM2.5, and PM1) spatial and temporal distribution in different types of environment in a Mediterranean urban region, the Greater Athens Area based on data from a sampling campaign that took place during the cold and warm period of 2008. The influence of the atmospheric circulation patterns, the possible local transport mechanisms, as well as the differentiation of the PM behaviour from that of the inorganic pollutants (NOx, O3), are analysed and discussed. Furthermore, the Comprehensive Air Quality Model with extensions (CAMx) was applied for selected sampling dates and its results were evaluated against measurements in order to interpret qualitatively the configured picture of the air pollution above the GAA. Analysis of the measurement data show that local sources such as traffic and industry dominate over the prevailing PM loads, especially at the 'hot spot' areas. Moreover, the synoptic circulation patterns associated with calm conditions and southerly flows lead to high particulate pollution levels that also affect the urban background stations. Saharan dust outbreaks appeared to increase the particles' diameter as well as the number of E.U. limit value exceedances within the stations of our network. Without any dependence on the characteristics of the investigated atmosphere, PM1 always constituted the greatest part of the PM2.5 mass while PM10, especially during the Saharan dust episodes, was mainly constituted by the coarse fraction. The numerical modelling approach of the geographical distribution of PM10, PM2.5, NOx and O3 justified the design of the sampling campaign, indicating the need for the systematic and parallel monitoring and modelling of the pollutants' dispersion in order to understand the particulate pollution problem in the GAA and to aid to the formulation of pollution control strategies. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Meteorological controls on atmospheric particulate pollution during hazard reduction burns

    Science.gov (United States)

    Di Virgilio, Giovanni; Hart, Melissa Anne; Jiang, Ningbo

    2018-05-01

    Internationally, severe wildfires are an escalating problem likely to worsen given projected changes to climate. Hazard reduction burns (HRBs) are used to suppress wildfire occurrences, but they generate considerable emissions of atmospheric fine particulate matter, which depend upon prevailing atmospheric conditions, and can degrade air quality. Our objectives are to improve understanding of the relationships between meteorological conditions and air quality during HRBs in Sydney, Australia. We identify the primary meteorological covariates linked to high PM2.5 pollution (particulates pollution, the PBLH between 00:00 and 07:00 LT (local time) was 100-200 m higher than days with high pollution. The PBLH was similar during 10:00-17:00 LT for both low and high pollution days, but higher after 18:00 LT for HRB days with low pollution. Cloud cover, temperature and wind speed reflected the above pattern, e.g. mean temperatures and wind speeds were 2 °C cooler and 0.5 m s-1 lower during mornings and evenings of HRB days when air quality was poor. These cooler, more stable morning and evening conditions coincide with nocturnal westerly cold air drainage flows in Sydney, which are associated with reduced mixing height and vertical dispersion, leading to the build-up of PM2.5. These findings indicate that air pollution impacts may be reduced by altering the timing of HRBs by conducting them later in the morning (by a matter of hours). Our findings support location-specific forecasts of the air quality impacts of HRBs in Sydney and similar regions elsewhere.

  14. Qualitative and quantitative determination of water in airborne particulate matter

    Directory of Open Access Journals (Sweden)

    S. Canepari

    2013-02-01

    Full Text Available This paper describes the optimization and validation of a new simple method for the quantitative determination of water in atmospheric particulate matter (PM. The analyses are performed by using a coulometric Karl-Fisher system equipped with a controlled heating device; different water contributions are separated by the application of an optimized thermal ramp (three heating steps: 50–120 °C, 120–180 °C, 180–250 °C.

    The analytical performance of the method was verified by using standard materials containing 5.55% and 1% by weight of water. The recovery was greater than 95%; the detection limit was about 20 μg. The method was then applied to NIST Reference Materials (NIST1649a, urban particulate matter and to real PM10 samples collected in different geographical areas. In all cases the repeatability was satisfactory (10–15%.

    When analyzing the Reference Material, the separation of four different types of water was obtained. In real PM10 samples the amount of water and its thermal profile differed as a function of the chemical composition of the dust. Mass percentages of 3–4% of water were obtained in most samples, but values up to about 15% were reached in areas where the chemical composition of PM is dominated by secondary inorganic ions and organic matter. High percentages of water were also observed in areas where PM is characterized by the presence of desert dust.

    A possible identification of the quality of water released from the samples was tried by applying the method to some hygroscopic compounds that are likely contained in PM (pure SiO2, Al2O3, ammonium salts, carbohydrates and dicarboxylic acids and by comparing the results with those obtained from field samples.

  15. Particulate matter emissions of different brands of mentholated cigarettes.

    Science.gov (United States)

    Gerharz, Julia; Bendels, Michael H K; Braun, Markus; Klingelhöfer, Doris; Groneberg, David A; Mueller, Ruth

    2018-01-09

    Inhaling particulate matter (PM) in environmental tobacco smoke (ETS) endangers the health of nonsmokers. Menthol, an additive in cigarettes, attenuates respiratory irritation of tobacco smoke. It reduces perceptibility of smoke and therefore passive smokers may inhale ETS unnoticed. To investigate a possible effect of menthol on PM concentrations (PM 10 , PM 2.5 , and PM 1 ), ETS of four mentholated cigarette brands (Elixyr Menthol, Winston Menthol, Reyno Classic, and Pall Mall Menthol Blast) with varying menthol content was analyzed. ETS was generated in a standardized way using an automatic environmental tobacco smoke emitter (AETSE), followed by laser aerosol spectrometry. This analysis shows that the tested cigarette brands, despite having different menthol concentrations, do not show differences with regard to PM emissions, with the exception of Reyno Classic, which shows an increased emission, although the menthol level ranged in the midfield. More than 90% of the emitted particles had a size smaller than or equal to 1 µm. Regardless of the menthol level, the count median diameter (CMD) and the mass median diameter (MMD) were found to be 0.3 µm and 0.5 µm, respectively. These results point out that there is no effect of menthol on PM emission and that other additives might influence the increased PM emission of Reyno Classic. Particulate matter (PM) in ETS endangers the health of nonsmokers and smokers. This study considers the effect of menthol, an additive in cigarettes, on PM emissions. Does menthol increase the amount of PM? Due to the exposure to secondhand smoke nearly 900,000 people die each year worldwide. The aim of the study is to measure the particle concentration (L -1 ), mass concentration (µg m -3 ), and dust mass fractions shown as PM 10 , PM 2.5 , and PM 1 of five different cigarette brands, including four with different menthol concentrations and one menthol-free reference cigarette, in a well-established standardized system.

  16. Toward understanding the role of cartilage particulates in synovial inflammation.

    Science.gov (United States)

    Silverstein, A M; Stefani, R M; Sobczak, E; Tong, E L; Attur, M G; Shah, R P; Bulinski, J C; Ateshian, G A; Hung, C T

    2017-08-01

    Arthroscopy with lavage and synovectomy can remove tissue debris from the joint space and the synovial lining to provide pain relief to patients with osteoarthritis (OA). Here, we developed an in vitro model to study the interaction of cartilage wear particles with fibroblast-like synoviocytes (FLS) to better understand the interplay of cartilage particulates with cytokines on cells of the synovium. In this study sub-10 μm cartilage particles or 1 μm latex particles were co-cultured with FLS ±10 ng/mL interleukin-1α (IL-1α) or tumor necrosis factor-α (TNF-α). Samples were analyzed for DNA, glycosaminoglycan (GAG), and collagen, and media samples were analyzed for media GAG, nitric oxide (NO) and prostaglandin-E2 (PGE2). The nature of the physical interaction between the particles and FLS was determined by microscopy. Both latex and cartilage particles could be phagocytosed by FLS. Cartilage particles were internalized and attached to the surface of both dense monolayers and individual cells. Co-culture of FLS with cartilage particulates resulted in a significant increase in cell sheet DNA and collagen content as well as NO and PGE2 synthesis compared to control and latex treated groups. The proliferative response of FLS to cartilage wear particles resulted in an overall increase in extracellular matrix (ECM) content, analogous to the thickening of the synovial lining observed in OA patients. Understanding how cartilage particles interface with the synovium may provide insight into how this interaction contributes to OA progression and may guide the role of lavage and synovectomy for degenerative disease. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  17. Evaluation of characterisation techniques for particulate weld fume morphology

    International Nuclear Information System (INIS)

    Sterjovski, Z.; Monaghan, B.J.; Norrish, J.

    2009-01-01

    An evaluation of three techniques: scanning electron microscopy (SEM); transmission electron microscopy (TEM); and laser diffraction (LD), was carried out to determine the most suitable technique for the particle-size measurement of particulate-welding fume collected during the robotic gas-metal-arc welding (GMAW) of plain-carbon steel. Particulate fume was deposited onto an Al stub positioned at a horizontal distance of 30 mm and a vertical height of 50 mm from the welding arc, and was then prepared for SEM, TEM and LD sizing. Results are presented for paniculate-welding fume collected for three welding voltages (20, 23 and 26 V) and two metal-transfer modes (dip and dip/globular). TEM imaging was found to be the most effective of the three sizing technique as it was able to resolve both fine nano-particles (5 ran diameter) and coarse nano-particles (>100 mn diameter). The TEM approach showed that results determined were reproducible and that the majority of fume particles produced at the welding voltages investigated were less than 40 nm in diameter. SEM (La B6 filament) images were shown to be inadequate for the quantitative-size analysis of paniculate-welding fume due to the limited resolution of the microscope (-40 nm). However. SEM images did confirm that at a welding voltage of 23 V the majority of particle sizes produced were less than 100 nm in diameter, and thus supported the conclusion that the individual fume particles are predominantly in the nanometre size range. LD gave unexpectedly large mean particle sizes and did not detect particles less than 180 run in diameter. It is concluded that the LD technique measures particle agglomerates and/or simultaneously monitors multiple particles in the beam path.

  18. Modelization of the radon emanation from natural sources in the soil

    International Nuclear Information System (INIS)

    Sabir, A.; Marah, H.; Hlou, L.; Klein, D.; Chambaudet, A.

    1996-01-01

    To evaluate the radon emanation and hence the risk to populations, we have adapted an original mathematical model based on the method of distribute parcels (L. Hlou, These d'etat, Faculte des Sciences, Kenitra, MAROC, 1994). This allows us to follow the migration, in time and space, of a quantity of radon produced in a unit volume as a function of the geological, morphological and structural characteristics of the site studied. Knowing the petrographic and pedologic parameters enables us to calculate the radon concentration in all points inside the soil of the site as well as the radon emanation in the atmosphere. It is therefore possible to calculate the radiological risk for populations brought to live on the site studied. Different applications of this model have been realised in Morocco and in France to demonstrate its efficiency. (author)

  19. The particulate matter dispersion studies from a local palm oil mill

    International Nuclear Information System (INIS)

    Abdullah, L.C.; Wong, L. L.; Amnorzahira, A.; Sa'ari, M.; Abdul Rashid, M. S.; Salmiaton Ali

    2006-01-01

    The appearance of industrial emissions and the degradation of scenic vistas are two characteristics of air pollution that humans object. Reduction in visibility suggests worsening pollution levels. The emissions from mobile source and stationary source are the major source of air pollutions contribution in Malaysia. Suspended particulate matter (SPM). The consequence of increasing the particulate concentrations, the particulate matter dissolves with vapour and grows into droplets when the humidity exceeds approximately 70% and causing opaque situation know as haze. This work focuses on the dispersion particulate matter from palm oil mill. The data obtained serves the purpose of modeling the transport of particulate matter for obtaining permits and prevention of significant deterioration (PSD) to the environment. Gaussian Plume Model from a point source, subject to various atmospheric conditions is used to calculate particulate matter concentration then display the distribution of plume dispersion using geographic information system (GIS). The calculated particulate matter concentration is evaluated using Transilient Matrice function. Atmospheric Stability, mixing height, wind direction, wind speed, natural and artificial features play an important role in dispersion process. High concentration area exhibits immediately under prevailing wind direction. (Author)

  20. On-Board Particulate Filter Failure Prevention and Failure Diagnostics Using Radio Frequency Sensing

    Energy Technology Data Exchange (ETDEWEB)

    Sappok, Alex [Filter Sensing Technologies; Ragaller, Paul [Filter Sensing Technologies; Herman, Andrew [CTS Corporation; Bromberg, L. [Massachusetts Institute of Technology (MIT); Prikhodko, Vitaly Y [ORNL; Parks, II, James E [ORNL; Storey, John Morse [ORNL

    2017-01-01

    The increasing use of diesel and gasoline particulate filters requires advanced on-board diagnostics (OBD) to prevent and detect filter failures and malfunctions. Early detection of upstream (engine-out) malfunctions is paramount to preventing irreversible damage to downstream aftertreatment system components. Such early detection can mitigate the failure of the particulate filter resulting in the escape of emissions exceeding permissible limits and extend the component life. However, despite best efforts at early detection and filter failure prevention, the OBD system must also be able to detect filter failures when they occur. In this study, radio frequency (RF) sensors were used to directly monitor the particulate filter state of health for both gasoline particulate filter (GPF) and diesel particulate filter (DPF) applications. The testing included controlled engine dynamometer evaluations, which characterized soot slip from various filter failure modes, as well as on-road fleet vehicle tests. The results show a high sensitivity to detect conditions resulting in soot leakage from the particulate filter, as well as potential for direct detection of structural failures including internal cracks and melted regions within the filter media itself. Furthermore, the measurements demonstrate, for the first time, the capability to employ a direct and continuous monitor of particulate filter diagnostics to both prevent and detect potential failure conditions in the field.

  1. Tile Effect of P reconsolidation on the Thermal Conductivity of Particulate Beds

    International Nuclear Information System (INIS)

    Weidenfeld, G.

    2001-09-01

    The thermal conductivity of particulate beds is an important property for many industrial handling processes as well as storage of particulate materials. This property can be affected by a few conditions, such as, temperature and external axial pressure. In the first part of this work, a background for the thermal conductivity of particulate bed is given. This includes a review of experimental and theoretical studies on the thermal conductivity of particulate beds. It is also a reviewed parameters that influence the thermal conductivity of particulate beds, such as, temperature. This study presents a new experimental apparatus that enables to measure the thermal conductivity in steady-state while the particulate bed is under axial consolidation stresses. The experimental apparatus was analyzed and characterized experimentally and by numerical simulations. An analytical model, that predicts the thermal conductivity of particulate beds under axial consolidation stress was developed. The model results were compared to the experimental results for 0.5 and 1 mm steel spheres and showed a good agreement. The experimental results showed a significant effect of the compression state on the bed and its pre-consolidation for 0.5 and 1 mm steel spheres. The effect of the compression state on the bed and its pre-consolidation was even more significant for limestone powder

  2. The cytotoxicity and genotoxicity of soluble and particulate cobalt in human lung fibroblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Leah J.; Holmes, Amie L. [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Maine Center for Environmental Toxicology and Health, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Department of Applied Medical Science, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Kandpal, Sanjeev Kumar; Mason, Michael D. [Department of Chemical and Biological Engineering, University of Maine, Orono, ME (United States); Zheng, Tongzhang [Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT (United States); Wise, John Pierce, E-mail: John.Wise@usm.maine.edu [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Maine Center for Environmental Toxicology and Health, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Department of Applied Medical Science, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States)

    2014-08-01

    Cobalt exposure is increasing as cobalt demand rises worldwide due to its use in enhancing rechargeable battery efficiency, super-alloys, and magnetic products. Cobalt is considered a possible human carcinogen with the lung being a primary target. However, few studies have considered cobalt-induced toxicity in human lung cells. Therefore, in this study, we sought to determine the cytotoxicity and genotoxicity of particulate and soluble cobalt in human lung cells. Cobalt oxide and cobalt chloride were used as representative particulate and soluble cobalt compounds, respectively. Exposure to both particulate and soluble cobalt induced a concentration-dependent increase in cytotoxicity, genotoxicity, and intracellular cobalt ion levels. Based on intracellular cobalt ion levels, we found that soluble cobalt was more cytotoxic than particulate cobalt while particulate and soluble cobalt induced similar levels of genotoxicity. However, soluble cobalt induced cell cycle arrest indicated by the lack of metaphases at much lower intracellular cobalt concentrations compared to cobalt oxide. Accordingly, we investigated the role of particle internalization in cobalt oxide-induced toxicity and found that particle-cell contact was necessary to induce cytotoxicity and genotoxicity after cobalt exposure. These data indicate that cobalt compounds are cytotoxic and genotoxic to human lung fibroblasts, and solubility plays a key role in cobalt-induced lung toxicity. - Highlights: • Particulate and soluble cobalt are cytotoxic and genotoxic to human lung cells. • Soluble cobalt induces more cytotoxicity compared to particulate cobalt. • Soluble and particulate cobalt induce similar levels of genotoxicity. • Particle-cell contact is required for particulate cobalt-induced toxicity.

  3. Measurement and analysis of ambient atmospheric particulate matter in urban and remote environments

    Science.gov (United States)

    Hagler, Gayle S. W.

    Atmospheric particulate matter pollution is a challenging environmental concern in both urban and remote locations worldwide. It is intrinsically difficult to control, given numerous anthropogenic and natural sources (e.g. fossil fuel combustion, biomass burning, dust, and seaspray) and atmospheric transport up to thousands of kilometers after production. In urban regions, fine particulate matter (particles with diameters under 2.5 mum) is of special concern for its ability to penetrate the human respiratory system and threaten cardiopulmonary health. A second major impact area is climate, with particulate matter altering Earth's radiative balance through scattering and absorbing solar radiation, modifying cloud properties, and reducing surface reflectivity after deposition in snow-covered regions. While atmospheric particulate matter has been generally well-characterized in populated areas of developed countries, particulate pollution in developing nations and remote regions is relatively unexplored. This thesis characterizes atmospheric particulate matter in locations that represent the extreme ends of the spectrum in terms of air pollution-the rapidly-developing and heavily populated Pearl River Delta Region of China, the pristine and climate-sensitive Greenland Ice Sheet, and a remote site in the Colorado Rocky Mountains. In China, fine particles were studied through a year-long field campaign at seven sites surrounding the Pearl River Delta. Fine particulate matter was analyzed for chemical composition, regional variation, and meteorological impacts. On the Greenland Ice Sheet and in the Colorado Rocky Mountains, the carbonaceous fraction (organic and elemental carbon) of particulate matter was studied in the atmosphere and snow pack. Analyses included quantifying particulate chemical and optical properties, assessing atmospheric transport, and evaluating post-depositional processing of carbonaceous species in snow.

  4. Nondestructive Determination of Reinforcement Volume Fractions in Particulate Composites : Ultrasonic Method

    International Nuclear Information System (INIS)

    Jeong, Hyun Jo

    1998-01-01

    A nondestructive ultrasonic technique is presented for estimating the reinforcement volume fractions of particulate composites. The proposed technique employs a theoretical model which accounts for composite microstructures, together with a measurement of ultrasonic velocity to determine the reinforcement volume fractions. The approach is used for a wide range of SiC particulate reinforced Al matrix (SiC p /AI) composites. The method is considered to be reliable in determining the reinforcement volume fractions. The technique could be adopted in a production unit for the quality assessment of the metal matrix particulate composite extrusions

  5. Electrification of particulate entrained fluid flows-Mechanisms, applications, and numerical methodology

    Science.gov (United States)

    Wei, Wei; Gu, Zhaolin

    2015-10-01

    Particulates in natural and industrial flows have two basic forms: liquid (droplet) and solid (particle). Droplets would be charged in the presence of the applied electric field (e.g. electrospray). Similar to the droplet charging, particles can also be charged under the external electric field (e.g. electrostatic precipitator), while in the absence of external electric field, tribo-electrostatic charging is almost unavoidable in gas-solid two-phase flows due to the consecutive particle contacts (e.g. electrostatic in fluidized bed or wind-blown sand). The particle charging may be beneficial, or detrimental. Although electrostatics in particulate entrained fluid flow systems have been so widely used and concerned, the mechanisms of particulate charging are still lack of a thorough understanding. The motivation of this review is to explore a clear understanding of particulate charging and movement of charged particulate in two-phase flows, by summarizing the electrification mechanisms, physical models of particulate charging, and methods of charging/charged particulate entrained fluid flow simulations. Two effective methods can make droplets charged in industrial applications: corona charging and induction charging. The droplet charge to mass ratio by corona charging is more than induction discharge. The particle charging through collisions could be attributed to electron transfer, ion transfer, material transfer, and/or aqueous ion shift on particle surfaces. The charges on charged particulate surface can be measured, nevertheless, the charging process in nature or industry is difficult to monitor. The simulation method might build a bridge of investigating from the charging process to finally charged state on particulate surface in particulate entrained fluid flows. The methodology combining the interface tracking under the action of the applied electric with the fluid flow governing equations is applicable to the study of electrohydrodynamics problems. The charge

  6. Sanitary impact of the particulate atmospheric urban pollution; Impact sanitaire de la pollution atmospherique urbaine particulaire

    Energy Technology Data Exchange (ETDEWEB)

    Sentissi, M.

    1999-03-22

    The pollution of particulates origin is one of the principle actual problem relative to air quality. In France, the fine particulates come from industry and automobile traffic, especially, the diesel vehicles. The most worrying characteristic is their fineness, that allow them to stay in suspension during a long time and penetrate into pulmonary alveoli, with toxic elements at their surface such metals, acids, polycyclic aromatic hydrocarbons. The objective of this work is to take stock of epidemiology and toxicology studies evaluating the sanitary impact of particulates in suspension. (N.C.)

  7. Electrification of particulate entrained fluid flows—Mechanisms, applications, and numerical methodology

    International Nuclear Information System (INIS)

    Wei, Wei; Gu, Zhaolin

    2015-01-01

    Particulates in natural and industrial flows have two basic forms: liquid (droplet) and solid (particle). Droplets would be charged in the presence of the applied electric field (e.g. electrospray). Similar to the droplet charging, particles can also be charged under the external electric field (e.g. electrostatic precipitator), while in the absence of external electric field, tribo-electrostatic charging is almost unavoidable in gas–solid two-phase flows due to the consecutive particle contacts (e.g. electrostatic in fluidized bed or wind-blown sand). The particle charging may be beneficial, or detrimental. Although electrostatics in particulate entrained fluid flow systems have been so widely used and concerned, the mechanisms of particulate charging are still lack of a thorough understanding. The motivation of this review is to explore a clear understanding of particulate charging and movement of charged particulate in two-phase flows, by summarizing the electrification mechanisms, physical models of particulate charging, and methods of charging/charged particulate entrained fluid flow simulations. Two effective methods can make droplets charged in industrial applications: corona charging and induction charging. The droplet charge to mass ratio by corona charging is more than induction discharge. The particle charging through collisions could be attributed to electron transfer, ion transfer, material transfer, and/or aqueous ion shift on particle surfaces. The charges on charged particulate surface can be measured, nevertheless, the charging process in nature or industry is difficult to monitor. The simulation method might build a bridge of investigating from the charging process to finally charged state on particulate surface in particulate entrained fluid flows. The methodology combining the interface tracking under the action of the applied electric with the fluid flow governing equations is applicable to the study of electrohydrodynamics problems. The

  8. Lagrangian analysis of multiscale particulate flows with the particle finite element method

    Science.gov (United States)

    Oñate, Eugenio; Celigueta, Miguel Angel; Latorre, Salvador; Casas, Guillermo; Rossi, Riccardo; Rojek, Jerzy

    2014-05-01

    We present a Lagrangian numerical technique for the analysis of flows incorporating physical particles of different sizes. The numerical approach is based on the particle finite element method (PFEM) which blends concepts from particle-based techniques and the FEM. The basis of the Lagrangian formulation for particulate flows and the procedure for modelling the motion of small and large particles that are submerged in the fluid are described in detail. The numerical technique for analysis of this type of multiscale particulate flows using a stabilized mixed velocity-pressure formulation and the PFEM is also presented. Examples of application of the PFEM to several particulate flows problems are given.

  9. Electrification of particulate entrained fluid flows—Mechanisms, applications, and numerical methodology

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Wei [School of Energy and Power Engineering, Wuhan University of Technology, Wuhan, Hubei, 430063 (China); School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, 710049 (China); Gu, Zhaolin, E-mail: guzhaoln@mail.xjtu.edu.cn [School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, 710049 (China)

    2015-10-28

    Particulates in natural and industrial flows have two basic forms: liquid (droplet) and solid (particle). Droplets would be charged in the presence of the applied electric field (e.g. electrospray). Similar to the droplet charging, particles can also be charged under the external electric field (e.g. electrostatic precipitator), while in the absence of external electric field, tribo-electrostatic charging is almost unavoidable in gas–solid two-phase flows due to the consecutive particle contacts (e.g. electrostatic in fluidized bed or wind-blown sand). The particle charging may be beneficial, or detrimental. Although electrostatics in particulate entrained fluid flow systems have been so widely used and concerned, the mechanisms of particulate charging are still lack of a thorough understanding. The motivation of this review is to explore a clear understanding of particulate charging and movement of charged particulate in two-phase flows, by summarizing the electrification mechanisms, physical models of particulate charging, and methods of charging/charged particulate entrained fluid flow simulations. Two effective methods can make droplets charged in industrial applications: corona charging and induction charging. The droplet charge to mass ratio by corona charging is more than induction discharge. The particle charging through collisions could be attributed to electron transfer, ion transfer, material transfer, and/or aqueous ion shift on particle surfaces. The charges on charged particulate surface can be measured, nevertheless, the charging process in nature or industry is difficult to monitor. The simulation method might build a bridge of investigating from the charging process to finally charged state on particulate surface in particulate entrained fluid flows. The methodology combining the interface tracking under the action of the applied electric with the fluid flow governing equations is applicable to the study of electrohydrodynamics problems. The

  10. Particulate emissions from diesel engines: correlation between engine technology and emissions.

    Science.gov (United States)

    Fiebig, Michael; Wiartalla, Andreas; Holderbaum, Bastian; Kiesow, Sebastian

    2014-03-07

    In the last 30 years, diesel engines have made rapid progress to increased efficiency, environmental protection and comfort for both light- and heavy-duty applications. The technical developments include all issues from fuel to combustion process to exhaust gas aftertreatment. This paper provides a comprehensive summary of the available literature regarding technical developments and their impact on the reduction of pollutant emission. This includes emission legislation, fuel quality, diesel engine- and exhaust gas aftertreatment technologies, as well as particulate composition, with a focus on the mass-related particulate emission of on-road vehicle applications. Diesel engine technologies representative of real-world on-road applications will be highlighted.Internal engine modifications now make it possible to minimize particulate and nitrogen oxide emissions with nearly no reduction in power. Among these modifications are cooled exhaust gas recirculation, optimized injections systems, adapted charging systems and optimized combustion processes with high turbulence. With introduction and optimization of exhaust gas aftertreatment systems, such as the diesel oxidation catalyst and the diesel particulate trap, as well as NOx-reduction systems, pollutant emissions have been significantly decreased. Today, sulfur poisoning of diesel oxidation catalysts is no longer considered a problem due to the low-sulfur fuel used in Europe. In the future, there will be an increased use of bio-fuels, which generally have a positive impact on the particulate emissions and do not increase the particle number emissions.Since the introduction of the EU emissions legislation, all emission limits have been reduced by over 90%. Further steps can be expected in the future. Retrospectively, the particulate emissions of modern diesel engines with respect to quality and quantity cannot be compared with those of older engines. Internal engine modifications lead to a clear reduction of the

  11. NewIn-situ synthesis method of magnesium matrix composites reinforced with TiC particulates

    Directory of Open Access Journals (Sweden)

    Zhang Xiuqing

    2006-12-01

    Full Text Available Magnesium matrix composites reinforced with TiC particulates was prepared using a new in-situ synthesis method of remelting and dilution technique. And measurements were performed on the composites. The results of x ray diffraction (XRD analysis confirmed that TiC particulates were synthesized during the sintering process, and they retained in magnesium matrix composites after the remelting and dilution processing. From the microstructure characterization and electron probe microanalysis (EPMA, we could see that fine TiC particulates distributed uniformly in the matrix material.

  12. Remote monitoring of environmental particulate pollution - A problem in inversion of first-kind integral equations

    Science.gov (United States)

    Fymat, A. L.

    1975-01-01

    The determination of the microstructure, chemical nature, and dynamical evolution of scattering particulates in the atmosphere is considered. A description is given of indirect sampling techniques which can circumvent most of the difficulties associated with direct sampling techniques, taking into account methods based on scattering, extinction, and diffraction of an incident light beam. Approaches for reconstructing the particulate size distribution from the direct and the scattered radiation are discussed. A new method is proposed for determining the chemical composition of the particulates and attention is given to the relevance of methods of solution involving first kind Fredholm integral equations.

  13. Assessment of inhalation dose sensitivity by physicochemical properties of airborne particulates containing naturally occurring radioactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Si Young; Choi, Cheol Kyu; Kim, Yong Geon; Choi, Won Chul; Kim, Kwang Pyo [Kyung Hee University, Seoul (Korea, Republic of)

    2015-12-15

    Facilities processing raw materials containing naturally occurring radioactive materials (NORM) may give rise to enhanced radiation dose to workers due to chronic inhalation of airborne particulates. Internal radiation dose due to particulate inhalation varies depending on particulate properties, including size, shape, density, and absorption type. The objective of the present study was to assess inhalation dose sensitivity to physicochemical properties of airborne particulates. Committed effective doses to workers resulting from inhalation of airborne particulates were calculated based on International Commission on Radiological Protection 66 human respiratory tract model. Inhalation dose generally increased with decreasing particulate size. Committed effective doses due to inhalation of 0.01μm sized particulates were higher than doses due to 100μm sized particulates by factors of about 100 and 50 for {sup 238}U and {sup 230}Th, respectively. Inhalation dose increased with decreasing shape factor. Shape factors of 1 and 2 resulted in dose difference by about 18 %. Inhalation dose increased with particulate mass density. Particulate mass densities of 11 g·cm{sup -3} and 0.7 g·cm{sup -3} resulted in dose difference by about 60 %. For {sup 238}U, inhalation doses were higher for absorption type of S, M, and F in that sequence. Committed effective dose for absorption type S of {sup 238}U was about 9 times higher than dose for absorption F. For {sup 230}Th, inhalation doses were higher for absorption type of F, M, and S in that sequence. Committed effective dose for absorption type F of {sup 230}Th was about 16 times higher than dose for absorption S. Consequently, use of default values for particulate properties without consideration of site specific physiochemical properties may potentially skew radiation dose estimates to unrealistic values up to 1-2 orders of magnitude. For this reason, it is highly recommended to consider site specific working materials and

  14. (Prérif Central, Maroc septentrional

    Directory of Open Access Journals (Sweden)

    Abdelghani Gartet

    2006-01-01

    Full Text Available El diapiro de sal de Tissa, situado en el Prerif central marroquí, afl ora en una zona de contacto estructural anormal donde la morfogénesis kárstica es muy activa. La solubilidad de las formaciones del complejo triásico es excesivamente fuerte. El macizo yesífero-salino representa un yacimiento de sal gema casi inagotable. Sin embargo, las aguas de Oued Lebène, en época de crecidas, socavan intensamente la base del macizo y terminan siendo afectadas por la contaminación química. La explotación de la cantera de sal, siendo tradicional, plantea numerosos problemas de planifi cación, a la vez que atenta severamente contra el medio ambiente (natural y urbano y contra la sociedad humana. Las medidas de defensa del medio ambiente adoptadas al respecto resultan por el momento insufi cientes dada la falta de una legislación práctica y rigurosa.

  15. (Prérif central, Maroc septentrional

    Directory of Open Access Journals (Sweden)

    Abdelghani Gartet

    2005-01-01

    Full Text Available El artículo tiene por objeto evaluar la degradación específi ca, y especialmente cuantifi car la carga de transporte sólido, en la cuenca del oued Lebène (Prérif central, caracterizada por altas tasas de erosión hídrica. La fuerte erosionabilidad de las rocas, la agresividad climática y las frecuentes variaciones de caudal hacen que el volumen de los materiales transportados por el Lebène alcancen una magnitud considerable. La irregularidad espacio-temporal de las precipitaciones y caudales condicionan el volumen de los transportes sólidos, de ahí las estrechas correlaciones existentes entre las tres variables. Los análisis relativos a la turbidez de las aguas y a la naturaleza granulométrica de los sedimentos refuerzan dicha relación.

  16. Global anthropogenic emissions of particulate matter including black carbon

    Science.gov (United States)

    Klimont, Zbigniew; Kupiainen, Kaarle; Heyes, Chris; Purohit, Pallav; Cofala, Janusz; Rafaj, Peter; Borken-Kleefeld, Jens; Schöpp, Wolfgang

    2017-07-01

    This paper presents a comprehensive assessment of historical (1990-2010) global anthropogenic particulate matter (PM) emissions including the consistent and harmonized calculation of mass-based size distribution (PM1, PM2. 5, PM10), as well as primary carbonaceous aerosols including black carbon (BC) and organic carbon (OC). The estimates were developed with the integrated assessment model GAINS, where source- and region-specific technology characteristics are explicitly included. This assessment includes a number of previously unaccounted or often misallocated emission sources, i.e. kerosene lamps, gas flaring, diesel generators, refuse burning; some of them were reported in the past for selected regions or in the context of a particular pollutant or sector but not included as part of a total estimate. Spatially, emissions were calculated for 172 source regions (as well as international shipping), presented for 25 global regions, and allocated to 0.5° × 0.5° longitude-latitude grids. No independent estimates of emissions from forest fires and savannah burning are provided and neither windblown dust nor unpaved roads emissions are included. We estimate that global emissions of PM have not changed significantly between 1990 and 2010, showing a strong decoupling from the global increase in energy consumption and, consequently, CO2 emissions, but there are significantly different regional trends, with a particularly strong increase in East Asia and Africa and a strong decline in Europe, North America, and the Pacific region. This in turn resulted in important changes in the spatial pattern of PM burden, e.g. European, North American, and Pacific contributions to global emissions dropped from nearly 30 % in 1990 to well below 15 % in 2010, while Asia's contribution grew from just over 50 % to nearly two-thirds of the global total in 2010. For all PM species considered, Asian sources represented over 60 % of the global anthropogenic total, and residential combustion

  17. Global anthropogenic emissions of particulate matter including black carbon

    Directory of Open Access Journals (Sweden)

    Z. Klimont

    2017-07-01

    Full Text Available This paper presents a comprehensive assessment of historical (1990–2010 global anthropogenic particulate matter (PM emissions including the consistent and harmonized calculation of mass-based size distribution (PM1, PM2. 5, PM10, as well as primary carbonaceous aerosols including black carbon (BC and organic carbon (OC. The estimates were developed with the integrated assessment model GAINS, where source- and region-specific technology characteristics are explicitly included. This assessment includes a number of previously unaccounted or often misallocated emission sources, i.e. kerosene lamps, gas flaring, diesel generators, refuse burning; some of them were reported in the past for selected regions or in the context of a particular pollutant or sector but not included as part of a total estimate. Spatially, emissions were calculated for 172 source regions (as well as international shipping, presented for 25 global regions, and allocated to 0.5°  ×  0.5° longitude–latitude grids. No independent estimates of emissions from forest fires and savannah burning are provided and neither windblown dust nor unpaved roads emissions are included. We estimate that global emissions of PM have not changed significantly between 1990 and 2010, showing a strong decoupling from the global increase in energy consumption and, consequently, CO2 emissions, but there are significantly different regional trends, with a particularly strong increase in East Asia and Africa and a strong decline in Europe, North America, and the Pacific region. This in turn resulted in important changes in the spatial pattern of PM burden, e.g. European, North American, and Pacific contributions to global emissions dropped from nearly 30 % in 1990 to well below 15 % in 2010, while Asia's contribution grew from just over 50 % to nearly two-thirds of the global total in 2010. For all PM species considered, Asian sources represented over 60 % of the global

  18. Transport of free and particulate-associated bacteria in karst

    Science.gov (United States)

    Mahler, B. J.; Personné, J.-C.; Lods, G. F.; Drogue, C.

    2000-12-01

    Karst aquifers, because of their unique hydrogeologic characteristics, are extremely susceptible to contamination by pathogens. Here we present the results of an investigation of contamination of a karst aquifer by fecal indicator bacteria. Two wells intercepting zones with contrasting effective hydraulic conductivities, as determined by pump test, were monitored both during the dry season and in response to a rain event. Samples were also collected from the adjacent ephemeral surface stream, which is known to be impacted by an upstream wastewater treatment plant after rainfall. Whole water and suspended sediment samples were analyzed for fecal coliforms and enterococci. During the dry season, pumping over a 2-day period resulted in increases in concentrations of fecal coliforms to greater than 10,000 CFU/100 ml in the high-conductivity well; enterococci and total suspended solids also increased, to a lesser degree. Toward the end of the pumping period, as much as 50% of the fecal coliforms were associated with suspended sediment. Irrigation of an up-gradient pine plantation with primary-treated wastewater is the probable source of the bacterial contamination. Sampling after a rain event revealed the strong influence of water quality of the adjacent Terrieu Creek on the ground water. Bacterial concentrations in the wells showed a rapid response to increased concentrations in the surface water, with fecal coliform concentrations in ground water ultimately reaching 60,000 CFU/100 ml. Up to 100% of the bacteria in the ground water was associated with suspended sediment at various times. The results of this investigation are evidence of the strong influence of surface water on ground water in karst terrain, including that of irrigation water. The large proportion of bacteria associated with particulates in the ground water has important implications for public health, as bacteria associated with particulates may be more persistent and more difficult to inactivate. The

  19. Production of particulates from transducer erosion: implications on food safety.

    Science.gov (United States)

    Mawson, Raymond; Rout, Manoj; Ripoll, Gabriela; Swiergon, Piotr; Singh, Tanoj; Knoerzer, Kai; Juliano, Pablo

    2014-11-01

    The formation of metallic particulates from erosion was investigated by running a series of transducers at various frequencies in water. Two low frequency transducer sonotrodes were run for 7.5h at 18kHz and 20kHz. Three high frequency plates operating at megasonic frequencies of 0.4MHz, 1MHz, and 2MHz were run over a 7days period. Electrical conductivity and pH of the solution were measured before and after each run. A portion of the non-sonicated and treated water was partially evaporated to achieve an 80-fold concentration of particles and then sieved through nano-filters of 0.1μm, 0.05μm, and 0.01μm. An aliquot of the evaporated liquid was also completely dried on strips of carbon tape to determine the presence of finer particles post sieving. An aliquot was analyzed for detection of 11 trace elements by Inductively Coupled Plasma Mass Spectroscopy (ICPMS). The filters and carbon tapes were analyzed by FE-SEM imaging to track the presence of metals by EDS (Energy Dispersive Spectroscopy) and measure the particle size and approximate composition of individual particles detected. Light microscopy visualization was used to calculate the area occupied by the particles present in each filter and high resolution photography was used for visualization of sonotrode surfaces. The roughness of all transducers before and after sonication was tested through profilometry. No evidence of formation of nano-particles was found at any tested frequency. High amounts of metallic micron-sized particles at 18kHz and 20kHz formed within a day, while after 7day runs only a few metallic micro particles were detected above 0.4MHz. Erosion was corroborated by an increase in roughness in the 20kHz tip after ultrasound. The elemental analysis showed that metal leach occurred but values remained below accepted drinking water limits, even after excessively long exposure to ultrasound. With the proviso that the particles measured here were only characterized in two dimensions and could be

  20. Understanding bulk behavior of particulate materials from particle scale simulations

    Science.gov (United States)

    Deng, Xiaoliang

    Particulate materials play an increasingly significant role in various industries, such as pharmaceutical manufacturing, food, mining, and civil engineering. The objective of this research is to better understand bulk behaviors of particulate materials from particle scale simulations. Packing properties of assembly of particles are investigated first, focusing on the effects of particle size, surface energy, and aspect ratio on the coordination number, porosity, and packing structures. The simulation results show that particle sizes, surface energy, and aspect ratio all influence the porosity of packing to various degrees. The heterogeneous force networks within particle assembly under external compressive loading are investigated as well. The results show that coarse-coarse contacts dominate the strong network and coarse-fine contacts dominate the total network. Next, DEM models are developed to simulate the particle dynamics inside a conical screen mill (comil) and magnetically assisted impaction mixer (MAIM), both are important particle processing devices. For comil, the mean residence time (MRT), spatial distribution of particles, along with the collision dynamics between particles as well as particle and vessel geometries are examined as a function of the various operating parameters such as impeller speed, screen hole size, open area, and feed rate. The simulation results can help better understand dry coating experimental results using comil. For MAIM system, the magnetic force is incorporated into the contact model, allowing to describe the interactions between magnets. The simulation results reveal the connections between homogeneity of mixture and particle scale variables such as size of magnets and surface energy of non-magnets. In particular, at the fixed mass ratio of magnets to non-magnets and surface energy the smaller magnets lead to better homogeneity of mixing, which is in good agreement with previously published experimental results. Last but not