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Assessing industrial pollution by means of environmental samples in the Kemi-Tornio region
Full text linkAbstractThe results of the comparison of various dissolution methods for sulphur showed, that HNO₃ together with H₂O₂ gave more complete decomposition of organic components than HNO₃ alone. The acid procedure with a mixture of HNO₃+H₂O₂slightly underestimated the S concentrations of plant material. The losses of sulphur were the highest in the dry ashing digestion procedure (HF(DAC)). The Leco combustion technique with infrared (IR) detection gave good precision and accuracy for sulphur. For the determination of heavy metals in plant materials, both the HNO₃ and HNO₃+H₂O₂ procedures were especially effective for determining Cr. However, the HNO₃+HClO₄ procedure gave lower results, and HF and HF(DAC) procedures greater values for Cr.Sulphur accumulation in pine needles around the pulp and paper mills was clearly higher than other points in the Kemi area. For example, within a radius of about 1–1.5 km around the mills of Oy Metsä-Botnia Ab Kemi Mills, the sulphur concentrations for (C) and (C+1) needles were 28% and 26% higher than those in the corresponding background samples collected in Kuivaniemi at a distance about 25 km from Kemi. Pine needles do not appeared to be appropriate a method for monitoring the accumulation of Fe, Zn, V and Pb emitted from pulp and paper mills. However, the Ca concentrations in (C+1) needles in the vicinity of the Oy Metsä-Botnia Ab Kemi Mills was 48% higher than the average Ca concentration calculated from all (C+1) needles; thus it is likely that part of the Ca in the needles is derived from the mills. The regional distribution pattern of Cr and Ni in mosses in the Kemi-Tornio area in 2000 showed clearly that the most polluted area (Cr > 200 μg/g and Ni > 20 μg/g) appeared to lie within a few kilometres of the ferrochrome and stainless steel works of AvestaPolarit Stainless Oy. Within this area, the Cr concentrations in mosses were 4–13 times higher than those outside the urban area of Tornio. The area most polluted by the opencast chromium mining complex (Cr > 200 μg/g and Ni All the 95th percentile values for TSP (total suspended particles) in the mine area of AvestaPolarit Chrome Oy Kemi Mine were below the current Finnish air quality limit value of 300 μg/m³ However, the 98th percentile value exceeded the Finnish air quality guideline value of 120 μg/m³ at one monitoring site.According to leaching studies, the sum of calculated annual airborne pollution impact of water-soluble fraction (H₂O) and environmentally mobile (CH₃COONH₄) fraction from the AvestaPolarit Chrome Oy Kemi Mine was Cr 1.2 kg, Fe 29 kg, Cu 63 kg, Ni 2.5 kg and Cd According to the homogeneity studies of heavy metal deposition on TSP filters, Cr, Ni, Cu and Fe were non-uniformly distributed over the glass fibre filters. The rsd values varied between 5.4–33.9 % for Cr, between 7.5–35.0 % for Ni, between 3.6–25.9 % for Cu, and between 6.6–19.9 % for Fe.Academic Dissertation to be presented with the assent of the Faculty of Science, University of Oulu, for public discussion in Raahensali (Auditorium L 10), Linnanmaa, on November 29th, 2002, at 12 noon.Abstract
The results of the comparison of various dissolution methods for sulphur showed, that HNO₃ together with H₂O₂ gave more complete decomposition of organic components than HNO₃ alone. The acid procedure with a mixture of HNO₃+H₂O₂slightly underestimated the S concentrations of plant material. The losses of sulphur were the highest in the dry ashing digestion procedure (HF(DAC)). The Leco combustion technique with infrared (IR) detection gave good precision and accuracy for sulphur. For the determination of heavy metals in plant materials, both the HNO₃ and HNO₃+H₂O₂ procedures were especially effective for determining Cr. However, the HNO₃+HClO₄ procedure gave lower results, and HF and HF(DAC) procedures greater values for Cr.
Sulphur accumulation in pine needles around the pulp and paper mills was clearly higher than other points in the Kemi area. For example, within a radius of about 1–1.5 km around the mills of Oy Metsä-Botnia Ab Kemi Mills, the sulphur concentrations for (C) and (C+1) needles were 28% and 26% higher than those in the corresponding background samples collected in Kuivaniemi at a distance about 25 km from Kemi. Pine needles do not appeared to be appropriate a method for monitoring the accumulation of Fe, Zn, V and Pb emitted from pulp and paper mills. However, the Ca concentrations in (C+1) needles in the vicinity of the Oy Metsä-Botnia Ab Kemi Mills was 48% higher than the average Ca concentration calculated from all (C+1) needles; thus it is likely that part of the Ca in the needles is derived from the mills.
The regional distribution pattern of Cr and Ni in mosses in the Kemi-Tornio area in 2000 showed clearly that the most polluted area (Cr > 200 μg/g and Ni > 20 μg/g) appeared to lie within a few kilometres of the ferrochrome and stainless steel works of AvestaPolarit Stainless Oy. Within this area, the Cr concentrations in mosses were 4–13 times higher than those outside the urban area of Tornio. The area most polluted by the opencast chromium mining complex (Cr > 200 μg/g and Ni < 20 μg/g) appeared to be in the immediate vicinity of complex.
All the 95th percentile values for TSP (total suspended particles) in the mine area of AvestaPolarit Chrome Oy Kemi Mine were below the current Finnish air quality limit value of 300 μg/m³ However, the 98th percentile value exceeded the Finnish air quality guideline value of 120 μg/m³ at one monitoring site.
According to leaching studies, the sum of calculated annual airborne pollution impact of water-soluble fraction (H₂O) and environmentally mobile (CH₃COONH₄) fraction from the AvestaPolarit Chrome Oy Kemi Mine was Cr 1.2 kg, Fe 29 kg, Cu 63 kg, Ni 2.5 kg and Cd < 100 mg.
According to the homogeneity studies of heavy metal deposition on TSP filters, Cr, Ni, Cu and Fe were non-uniformly distributed over the glass fibre filters. The rsd values varied between 5.4–33.9 % for Cr, between 7.5–35.0 % for Ni, between 3.6–25.9 % for Cu, and between 6.6–19.9 % for Fe
Chemical analysis of dust and biological samples for monitoring of occupational exposure to vanadium
No full textChemical analysis of dust and biological samples for monitoring of occupational exposure to vanadium
No full text
Particle Image Velocimetry –mittausten toteuttaminen PPOOLEX-lauhtumiskokeissa
Full text linkParticle Image Velocimetry, PIV, is an optical measuring technique to obtain velocity information of a flow in interest. With PIV it is possible to achieve two or three dimensional velocity vector fields from a measurement area instead of a single point in a flow. Measured flow can be either in liquid or in gas form. PIV is nowadays widely applied to flow field studies. The need for PIV is to obtain validation data for Computational Fluid Dynamics calculation programs that has been used to model blow down experiments in PPOOLEX test facility in the Lappeenranta University of Technology. In this thesis PIV and its theoretical background are presented. All the subsystems that can be considered to be part of a PIV system are presented as well with detail. Emphasis is also put to the mathematics behind the image evaluation. The work also included selection and successful testing of a PIV system, as well as the planning of the installation to the PPOOLEX facility.
Already in the preliminary testing PIV was found to be good addition to the measuring equipment for Nuclear Safety Research Unit of LUT. The installation to PPOOLEX facility was successful even though there were many restrictions considering it. All parts of the PIV system worked and they were found out to be appropriate for the planned use. Results and observations presented in this thesis are a good background to further PIV use.Particle Image Velocimetry, PIV, on optinen mittaustekniikka, jolla voidaan saada tutkittavasta virtauksesta nopeusinformaatiota. PIV-tekniikan avulla virtauksesta saadaan kaksi- tai kolmiulotteisia nopeusvektoreita tutkittavalta mitta-alueelta yhden pisteen sijasta. Mitattava virtaus voi olla joko kaasua tai nestettä. PIV-tekniikkaa sovelletaan nykyään laajalti virtausmittauksiin. PIV:llä on tarkoitus saada hankittua validointidataa laskennallisten virtausmallinnusohjelmien tarpeisiin Lappeenrannan teknillisen yliopiston, LUT, PPOOLEX-laitteiston ulospuhalluskokeiden mallinnusta varten. Tässä työssä esitellään PIV ja sen teoreettinen tausta. Työssä esitellään myös yksityiskohtaisesti kaikki PIV-mittauslaitteistoon luettavaksi kuuluvat osat ja kuvien analysoinnin matemaattinen tausta. Työhön kuului myös toimivan PIV-mittauslaitteiston kokoaminen ja testaus sekä sen sijoittamissuunnitelma PPOOLEX-laitteistoon.
Jo alustavissa kokeissa PIV:n havaittiin olevan hyvä lisä LUT:n Ydinturvallisuuden tutkimusyksikön mittauslaitteistoihin. Sijoittaminen ja asentaminen PPOOLEX-laitteistoon onnistui hyvin ja se todettiin toimivaksi, vaikkakin rajoituksia oli paljon. Kaikki PIV-mittalaitteiston osat toimivat ja ne todettiin tarkoituksenmukaisiksi. Työssä esitellyt tulokset ja huomiot ovat hyvä perusta PIV-mittauksille tulevaisuudessa
Irradiation Embrittlement of Reactor Pressure Vessels in Light Water Reactors
Full text linkTyössä käydään läpi säteilyhaurastumisilmiöitä ja niistä johtuvia vaikutuksia kevytvesilaitosten reaktoripainesäiliöilleThis thesis focuses on irradiation embrittlement of light water reactor pressure vessel
Chemical analysis of dust and biological samples for monitoring of occupational exposure to vanadium
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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