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Hassan, M.H.A.; Eltayeb, I.A.
Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)1998
Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)1998
AbstractAbstract
[en] A pollutant of small particles is emitted by a point source at a height h above ground level in an atmosphere in which a uni-directional wind speed, U, is prevailing. The pollutant is subjected to diffusion in all directions in the presence of advection and settling due to gravity. The equation governing the concentration of the pollutant is studied with the wind speed and the different components of diffusion tensor are proportional to the distance above ground level and the source has a uniform strength. Adopting a Cartesian system of coordinates in which the x-axis lies along the direction of the wind velocity, the z-axis is vertically upwards and the y-axis completes the right-hand triad, the solution for the concentration c(x,y,z) is obtained in closed form. The relative importance of the components of diffusion along the three axes is discussed. It is found that for any plane y=constant (=A), c(x,y,z) is concentrated along a curve of ''extensive pollution''. In the plane A=0, the concentration decreases along the line of extensive pollution as we move away from the source. However, for planes A≅0, the line of extensive pollution possesses a point of accumulation, which lies at a nonzero value of x. As we move away from the plane A=0, the point of accumulation moves laterally away from the plane x=0 and towards the plane z=0. The presence of the point of accumulation is entirely due to the presence of lateral diffusion. (author)
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Oct 1998; 36 p; 12 refs, 9 figs
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Hassan, M.H.A.; Eltayeb, I.A.
Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)2000
Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)2000
AbstractAbstract
[en] A fixed volume of pollutant of small particles is emitted by a point source at a height h above ground level, at a certain instant of time, in an infinite medium in which wind is blowing horizontally with a uniform speed, U. The pollutant is subject to diffusion in the presence of advection and settling due to gravity. The solution for the concentration is obtained in closed form for subsequent times. It is shown that as time increases the point volume spreads out under the influence of diffusion but the volume of dust always maintains a point of accumulation, where the concentration is a maximum. In the absence of horizontal diffusion, the dust moves as a vertical front with uniform speed U. In both cases the accumulation point moves horizontally with the flow speed but its height is a complicated function of diffusion (both horizontal and vertical) and gravity. The solution is illustrated graphically. (author)
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Oct 2000; 17 p; Refs, 4 figs
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[en] Already now the estimated daily average input of about 2 pg I-TEQ/kg body weight for an adult exceeds the preventive value of 1 pg I-TEQ/(kg x d) proposed by the Federal Environmental Agency (UBA) and the Federal Health Office (BGA), although the intervention value of 10 pg/(kg x d) also proposed by UBA and BGA has not been reached yet. To be able to take well-aimed measures to reduce dioxin emissions into the environment, it is necessary to collect sufficient information about the sources, the history of origins and the efficiency of control measures. The high number of investigations conducted into waste incineration plants, which can be explained by increasing public awareness of the disposal problem, gave the impression that waste incineration is one of the major causes of dioxin emissions into the environment. Analyses of the ambient air situation revealed that there is a considerable lack of information about the sources of dioxin emissions. For example, systematic investigations in North Rhine-Westphalia, which have not been finished yet, identified sintering plants as the main dioxin emittors. It can be concluded already now that control measures are indispensable for these plants to improve the ambient air situation; a few waste gas cleaning methods were tested. The realisation of the 17th Order Implementing the Federal Immission Control Act (17th BImSchV) (emission control of dioxins from waste incineration plants), the 19th BImSchV (prohibition of Cl and Br additions to fuels) and the further spread of the controlled catalytic coverter for passenger cars will make industrial dioxin sources even more relevant. This underlines the necessity for control measures in this field. (orig.)
[de]
Bereits jetzt ist mit einer geschaetzten mittleren taeglichen Aufnahme von ca. 2 pg I-TEQ/kg Koerpergewicht fuer einen Erwachsenen der von UBA und BGA vorgeschlagene Vorsorgewert von 1 pg I-TEQ/(kg x d) ueberschritten, wenn auch der von UBA und BGA ebenfalls vorgeschlagene Interventionswert von 10 pg/(kg x d) noch nicht erreicht ist. Um gezielt Massnahmen zur Verminderung des Dioxineintrages in die Umwelt ergreifen zu koennen, ist die Kenntnis der Quellen, der Entstehungsprozesse und der Effizienz von Minderungsmassnahmen erforderlich. Durch die hohe Untersuchungsdichte bei Muellverbrennungsanlagen, die insbesondere auf die intensive oeffentliche Diskussion ueber die Entsorgungsproblematik zurueckzufuehren ist, konnte der Eindruck entstehen, dass die Muellverbrennung massgeblich fuer den Dioxineintrag in die Umwelt verantwortlich ist. Analysen der Immissionssituation zeigten erhebliche Informationsdefizite ueber die Quellen des Dioxineintrages. Systematische Untersuchungen in NRW, die noch nicht abgeschlossen sind, haben z.B. nach aktuellem Stand Sinteranlagen als Hauptdioxinemittenten identifiziert. Bereits jetzt kann gesagt werden, dass Minderungsmassnahmen an diesen Anlagen unbedingt erforderlich sind, um langfristig eine Verbesserung der Immissionssituation zu erreichen; einzelne Abgasreinigungsverfahren wurden getestet. Die Umsetzung der 17. BImSchV (Emissionsbegrenzung der Dioxine aus Muellverbrennungsanlagen), der 19. BImSchV (Verbot von Cl- und Br-Zusaetzen in Kraftstoffen) und die weitere Verbreitung des geregelten Pkw-Katalysators werden dazu fuehren, dass Dioxin-Quellen im Bereich der Industrie eine noch groessere Bedeutung erlangen, was die Notwendigkeit entsprechender Minderungsmassnahmen in diesem Anlagenbereich unterstreicht. (orig.)Original Title
Emissionen von chlorierten Dioxinen und Furanen
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[en] Various methods of measuring immissions and immission rates and their effects were used in a 3-year study programme in the ambience of a fluoride-emitting brickyard. The effects of emission-abating measures taken by the emitter in the course of the study period were observed during certain phases and documented. Limited time resolution and the inevitable reduction in the number of measuring points curbed the informativeness of the fluoride immission measurements. The method of SAM immission rate measurement with its high resolution in time and space permitted monitoring atmospheric fluoride concentrations throughout the year. Although methods of bioindication are confined to the vegetation period, these procedures yielded effect-related information of great temporal and spatial density. Even without analytic methods, gladiolus exposition provides important information on pollution and an instructive profile of its effects. (orig.)
[de]
Verschiedene Verfahren der Immissionsmessung sowie der Immissionsraten- und biologischen Wirkungsmessung wurden waehrend eines 3jaehrigen Untersuchungsprogrammes in der Umgebung eines Fluorid-emittierenden Ziegeleibetriebes eingesetzt. Das Wirksamwerden emissionsmindernder Massnahmen bei diesem Emittenten wurde ueber verschiedene Phasen hinweg beobachtet und dokumentiert. Die begrenzte zeitliche Aufloesung und die zwangslaeufige Reduktion der Messstellenzahl beschraenkt die Aussagekraft der Fluorid-Immissionsmessungen. Das Verfahren der SAM-Immissionsratenmessung erlaubte bei hoher raeumlicher und zeitlicher Aufloesung eine ganzjaehrige Ueberwachung der atmosphaerischen Fluorid-Belastung. Der Einsatz von Bioindikationsverfahren ist auf die Vegetationsperiode beschraenkt, doch lieferten diese Verfahren wirkungsbezogene Aussagen hoher zeitlicher und raeumlicher Dichte. Auch ohne den Einsatz analytischer Verfahren bietet die Gladiolenexposition wichtige Belastungsaussagen mit hoher Wirkungsrelevanz. (orig.)Original Title
Messung der Fluorid-Immissionskonzentrationen - Immissionsraten (SAM), sowie aktives Biomonitoring eines lokalen Emittenten
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Kommission Reinhaltung der Luft im VDI und DIN, Duesseldorf (Germany); VDI-Berichte; v. 901(pt.2); 606 p; ISBN 3-18-090901-3;
; 1992; p. 801-811; VDI-Verl; Duesseldorf (Germany); International colloquium on bioindication - an efficient tool for pollution control; Internationales Kolloquium ueber Bioindikation - Ein Wirksames Instrument der Umweltkontrolle; Vienna (Austria); 24-26 Sep 1991; ISSN 0083-5560;
; CODEN VDIBAP


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Oprea, C.; Oprea, A.I.; Chernenko, L.P.
Joint Institute for Nuclear Research, Dubna (Russian Federation)
Neutron spectroscopy, nuclear structure, related topics. XI International seminar on interactions of neutrons with nuclei. Proceedings of the seminar2004
Joint Institute for Nuclear Research, Dubna (Russian Federation)
Neutron spectroscopy, nuclear structure, related topics. XI International seminar on interactions of neutrons with nuclei. Proceedings of the seminar2004
AbstractAbstract
[en] The factor analysis is a modern method of statistical analysis of the experimental data. This method applies in a broad range of sciences like psychology, economy, medicine, electronics, physics and other. This method allows one to extract from a set of experimental data some properties of the studied process (usually called 'hidden') when there is not any theoretical description of studied phenomena. In this study we have done a short presentation of factor analysis followed by some applications as the problem of the boxes (the classical one) and the problem of the polynoms. We apply the factor analysis to an ecological problem using a very simple model of the source of pollution (the gaussian one) by simulating the computer data
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316 p; ISBN 5-9530-0043-X;
; 2004; p. 214-219; 11. international seminar on interaction of neutrons with nuclei (ISINN 11); Dubna (Russian Federation); 28-31 May 2003; Available from the Joint Institute for Nuclear Research, Dubna (RU); website: http://www1.jinr.ru/index.html; e-mail: publish@pds.jinr.ru; 4 refs., 4 figs.

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[en] The authors show exact analytic solutions for hydrogeologic transport of contaminants from an array of point sources in a waste disposal site, and contaminants released from finite areal sources into a planar fracture. For dispersion from an array of sources, dispersion may be isotropic or anisotropic, and equilibrium sorption and radioactive decay are considered. For contaminant released into a fracture, the solution includes the effects of advection in the fracture, transverse dispersion and surface sorption, as well as diffusion into and sorption in the rock matrix. The authors illustrate the solutions through numerical and graphical displays of the spatial and temporal distribution of the contaminant. The numerical illustrations show that at a certain distance away from the sources, indicated by a distance parameter, equivalent single-source solutions give acceptable approximations
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Someshwar, A.V.; Caron, A.L.; Pinkerton, J.E.
American Chemical Society. Cellulose, Paper, and Textile Division1990
American Chemical Society. Cellulose, Paper, and Textile Division1990
AbstractAbstract
[en] The relationship between burning medium sulfur oil as auxiliary fuel in kraft recovery furnaces and SO2 emissions was examined. Analysis of long-term CEMS SO2 data from four furnaces shows no increase in SO2 emissions as a result of oil burning. The results of field tests conducted at four furnaces while co-firing oil with liquor (up to 34% of total heat input) show that (1) average SO2 emissions during the oil firing period either decreased or remained unchanged; (2) the overall sulfur retention within the furnace remained consistently high (more than 90%) with increasing levels of oil burning; (3) apportioning stack SO2 emissions between those derived from oil and black liquor was infeasible. The results indicate that the same alkali fume generation processes that lead to the efficient capture of SO2 resulting from black liquor combustion may be responsible for the capture of SO2 resulting from sulfur-containing oil combustion
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Anon; 25 p; 1990; p. 25, Paper CELL 81; American Chemical Society; Washington, DC (United States); 200. American Chemical Society (ACS) national meeting; Washington, DC (United States); 26-31 Aug 1990; CONF-900802--; American Chemical Society, 1155 16th Street, NW, Washington, DC 20036 (United States)
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[en] In this paper, assurance indices are introduced as measures of air quality; they take into account the pre-existent pollution and the different degrees of protection which each zone of the analysed area must be provided. The results are analyzed and discussed
[it]
In questo lavoro vengono proposti come indicatori della qualita' dell'aria degli indici di garanzia, che consentono di tenere conto dell'inquinamento di fondo preesistente l'esercizio dell'impianto e del diverso grado di tutela che si voglia assicurare alle varie zone del territorio. I risultati ottenuti vengono analizzati e discussiOriginal Title
La regolazione delle emissioni degli impianti a grande rilevanza ambientale mediante indici di garanzia di qualita' dell'aria
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Horstmann, M.
Bayreuth Univ. (Germany). Fakultaet fuer Biologie, Chemie und Geowissenschaften1994
Bayreuth Univ. (Germany). Fakultaet fuer Biologie, Chemie und Geowissenschaften1994
AbstractAbstract
[en] The investigation of non-industrial wastewater inputs to municipal wastewater treatment plants (MWTP) led to two results concerning the PCDD/F contamination of sewage sludge: 1.) Surface runoff does not represent a significant PCDD/F-input to sewage sludge. 2.) Household wastewater is one main source of PCDD/F in MWTPs. The prinicpal source of the PCDD/F in household wastewater was identified as PCDD/F-contaminated textiles. (orig./EF)
[de]
Die Untersuchung von nicht-industriellen Schmutzwassereinleitungen in kommunale Klaeranlagen fuehrten im Hinblick auf die PCDD/F-Belastung von Klaerschlaemmen zu zwei wichtigen Ergebnissen: 1. Die regenbedingten PCDD/F-Einleitungen in eine Klaeranlage spielen nur eine untergeordnete Rolle bei der Belastung von Klaerschlaemmen. 2. Haeusliche Abwaesser stellen eine der Hauptquellen von PCDD/F fuer Klaeranlagen dar. Als eigentliche PCDD/F-Quelle im Bereich der haeuslichen Abwaesser konnten mit PCDD/F-kontaminierte Textilien identifiziert werden. (orig./EF)Original Title
Untersuchungen zu nicht-industriellen Quellen von polychlorierten Dibenzo-p-Dioxinen (PCDD) und polychlorierten Dibenzofuranen (PCDF) in einem kommunalen Entwaesserungssystem
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Berichte aus der Chemie; 1994; 212 p; Shaker; Aachen (Germany); ISBN 3-8265-0233-7;
; Diss.

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AbstractAbstract
[en] On the basis of the reaction of a meadow plant community to pentachlorophenol (PCB) exposure, parameters were determined which provide information on the environmental impact of synthetic organic compounds. One of the most sensitive parametrs characterising structural changes in the plant community is the shift in species predominance. Functional parameters such as the photosynthesis capacity and the accumulation of carbohydrate reserves are important aids in explaining the effects of chemical substances on biomass formation from plant species. (orig.)
[de]
Die Reaktion der Pflanzengemeinschaft einer Wiese auf den Eintrag von Pentachlorphenol (PCP) dient zur Ermittlung von Parametern, die Aussagen zur Umweltwirksamkeit synthetischer organischer Verbindungen in der belebten Umwelt zulassen. Artmaechtigkeitsverschiebungen haben sich als besonders empfindlicher Faktor zur Kennzeichnung struktureller Veraenderungen in der Pflanzengemeinschaft erwiesen. Funktionelle Groessen wie das Photosynthese-Vermoegen und die Speicherung von Reserve-Kohlenhydraten bieten wichtige Hilfsmittel zur Erklaerung der Chemikalieneffekte auf die Biomassebildung der Pflanzenarten. (orig.)Original Title
Sensitives Biomonitoring von Xenobiotica in Gruenlandgesellschaften. T. 1
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Kommission Reinhaltung der Luft im VDI und DIN, Duesseldorf (Germany); VDI-Berichte; v. 901(pt.2); 606 p; ISBN 3-18-090901-3;
; 1992; p. 895-904; VDI-Verl; Duesseldorf (Germany); International colloquium on bioindication - an efficient tool for pollution control; Internationales Kolloquium ueber Bioindikation - Ein Wirksames Instrument der Umweltkontrolle; Vienna (Austria); 24-26 Sep 1991; ISSN 0083-5560;
; CODEN VDIBAP


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