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Baseline assessment of the density and diversity of birds around Matimba and Medupi power station / Luckson MuyemekiMuyemeki, Luckson January 2015 (has links)
Bird populations are changing at unprecedented rates in response to human-induced changes to
the global environment, and these rates of change are expected to accelerate over the coming
decades. Changes in the levels of sulphur dioxide (SO2) in the atmosphere through emissions
from power stations pose a potential threat to bird populations. However, avian response to SO2
pollution is poorly understood. Exploring the relationship between avian diversity and SO2
exposure levels will help in determining species sensitive to air pollution.
This study seeks to understand the interactions between avian diversity and SO2 concentration
levels around Matimba power station so as to have more insight on the level of avian vulnerability
to air pollution. Matimba is an important site in South Africa as a second coal fired power station,
Medupi, is currently being constructed with additional stations also a possibility. This study
represents an important baseline assessment of the avian population status before the additional
pollution burden is realised from Medupi.
Ten min repeated point counts were conducted at three sample sites with varying distances from
Matimba and Medupi power stations. These counts were used to calculate bird species density
and diversity. Cloud-free Landsat 8 imagery acquired on 7 January, 2014 was used to derive
habitat structure and productivity variables. Elevation variables were derived using a DEM (Digital
Elevation Model) obtained from NASA Global Data Explorer. The AERMOD dispersion model was
used to characterise spatio-temporal variations in ambient SO2 concentrations around Matimba
power station. Multiple regression analysis was then used to ascertain which of these variables
(SO2, habitat structure, productivity and terrain) contribute most to the observed variation in bird
species density and diversity around Matimba and Medupi power stations.
SO2 polluted air did not have an influence on bird species density and diversity at the community
level. At species level two species (Batis molitor and Streptopelia senegalensis) exhibited some
measure of negative response to SO2 air pollution. However, after further investigation using
multiple regression analysis it was revealed that habitat structure had more influence on the
density of these two species compared with ambient SO2 concentrations. Bird species density
and diversity varied significantly among the sample sites but were not related to the distance to
the source of the SO2 air pollution.
Evidence obtained from this study revealed that continuous monitoring of the interactions
between SO2 polluted air and bird populations is recommended for a more comprehensive
understanding of avian susceptibility towards SO2 air pollution and this will also facilitate in the selection of sensitive and relevant species for future ecology studies at other coal-fired power
stations. Furthermore, it is expected that SO2 concentrations will significantly increase with the
commissioning of Medupi power station thus further necessitating the need for continuous
monitoring of bird species densities around Matimba and Medupi power stations. / MSc (Geography and Environmental Management), North-West University, Potchefstroom Campus, 2015
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Synthesis and properties of sulphur-containing long chain fatty acid derivativesBakare, Oladapo. January 1993 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Autotrophic denitrification of synthetic wastewater in biological activated filter (BAF) reactors with sulfur mediaTam, Ka-man., 譚家雯. January 2006 (has links)
published_or_final_version / abstract / Civil Engineering / Master / Master of Philosophy
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Expression profiling of Bacillus subtilis sulfur responsive genes using S-methyl-cysteine (SMeC) as sole sulfur sourceYap, Yee-leng, Daniel. January 2006 (has links)
published_or_final_version / abstract / Microbiology / Doctoral / Doctor of Philosophy
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Pressure Dependence of Line Widths of Microwave Spectra of Sulphur DioxideYang, Wei Han 12 1900 (has links)
Measurements of line width parameters for eleven rotational transitions of type (J -- J + 1) of SO2 were made and are reported herein. The line width quantum number (J) trend was obtained. The microwave spectrograph used for these measurements of line width is described. Operational methods to operate the spectrograph are presented and discussed, with particular attention given to how to measure the line width. Suggestions for future avenues of probing this molecule to ascertain the non-uniform behavior of the line width parameter over the quantum number and frequency range are given.
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Environmental and host factors associated with persistent lower respiratory tract symptoms or asthma following acute environmental exposure to sulphur dioxide (S02).Baatjies, Roslynn 23 February 2007 (has links)
Student Number : 0316118X -
MPH research report -
School of Public Health -
Faculty of Health Sciences / Introduction: On the weekend of 16 – 17 December 1995, the community of Macassar
was exposed to elevated levels of sulphur dioxide vapours (SO2) caused by a fire on a
nearby stockpile for approximately 21.5 hours. It has been estimated that community
members were exposed to levels as high as 200 parts per million (ppm) of this gas as
some 15 000 tons of the sulphur stockpile ignited. This resulted in a toxic plume of SO2
being blown over the Macassar area by the prevailing wind. The aim of this study was to
assess the environmental and host factors associated with persistent lower respiratory
symptoms among residents of this community six years after being acutely exposed to
elevated exposures of SO2 vapours.
Materials and methods: A case-control study was conducted. The cases and controls
were selected from adult residents who reported to the Macassar disaster project clinic for
a health assessment in order to lodge a medico-legal claim. Survey instruments included a
questionnaire, clinical examination and clinical record review by an expert panel. A case
was defined as an adult resident who presented to the clinic for an examination with
persistent (at year 1 and 6 after the disaster) lower respiratory symptoms. Controls were
chosen from clinic attendees without lower respiratory symptoms at year 1 and 6.
Environmental exposure was calculated by using the Industrial Source Complex Short
Term Model (ISCST 3) to predict time-averaged concentrations at specified receptor
locations. Multiple logistic regression was used to investigate the association between
lower persistent respiratory symptoms, host and environmental factors (estimated
concentration and duration of exposure to SO2). Results: A total of 76 cases and 180 controls were selected. The cases and controls were
comparable with respect to age, gender, height and smoking status. The results indicated
that a medical history of pulmonary tuberculosis at least one year prior to the fire (OR:
3.5, CI: 1.5-8.4) was significantly associated with having persistent lower respiratory
symptoms. Furthermore, subjects with persistent lower respiratory symptoms were nine
times more likely to report symptoms of tight chest (OR: 9.9; CI: 5.2-19.1), and twice as
likely to report shortness of breath (OR: 2.0; CI: 1.0-4.1) at the time of the fire. None of
the exposure metrics (total hours of exposure, cumulative exposure, peak exposure) were
significantly associated with persistent lower respiratory symptoms. However, peak SO2
exposure estimated at hour 15 was significantly associated with persistent lower
respiratory symptoms (OR: 1.0; CI: 1.0-1.1).
Discussion: The results of this study are consistent with previous studies reporting lower
respiratory tract symptoms after chemical exposure irrespective of age or smoking status.
Furthermore, as in other studies respiratory health status was a significant factor in
determining susceptibility to SO2 exposure. Various reports in the literature suggest that
exposure > 20 ppm is associated with chronic respiratory symptoms. This however was
not demonstrated in this study, using estimates of exposure calculated using the ISCST
model suggesting possible exposure misclassification. “Self-selection” bias was an
important limitation in this study, since the entire study population was self-referred and
as such the study population was not randomly selected. Another limitation is the
possibility that there may be potential recall bias operating since the fire incident
happened six years ago; however this was considered unlikely as there was nondifferential
reporting between cases and control. Self reported symptoms on the
questionnaires might have been over-reported due to fear, anxiety and stress or secondary gain related to compensation issues. The lack of association between exposure variables
and persistent asthma may have also been due to lack of power (small sample size),
although this was thought to be a minor contributory factor.
Conclusion: Host-related factors such as a previous history of pulmonary TB and acute
asthma-like symptoms at the time of the fire were important predictors of persistent lower
respiratory symptoms reported by residents 6 years after acute exposure to SO2 vapours
emanating from a sulphur fire.
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Determinação isotópica de S (% em átomos de 34S) por espectrometria de massas em amostras de solo, a partir de S-Total e S-Sulfato disponível / Isotopic determination of S (% in atoms of 34S) by mass spectrometry in soil samples based on Total-S and available Sulphate-SRossete, Alexssandra Luiza Rodrigues Molina 31 January 2007 (has links)
O enxofre no solo pode ser encontrado em duas formas básicas como S-Inorgânico e S-Orgânico. O enxofre na forma inorgânica (S-Sulfato) pode estar prontamente disponível à planta, mas o enxofre orgânico é responsável por 95% do enxofre total na maioria dos solos. Com o objetivo de quantificar o sulfato disponível do solo utilizou-se como extrator solução de acetato de amônio em ácido acético. A eficiência da oxidação do S-Orgânico à S-Inorgânico, para determinação de S-Total em amostras de solo, foi avaliada com o emprego de métodos de oxidação por via úmida e seca. Para a quantificação do S-Total e S-Sulfato disponível foi desenvolvido um sistema automatizado de análise em fluxo (FIA) empregando multicomutação e amostragem binária. Os resultados das determinações de S-Total e de Sulfato disponível mostraram-se concordantes entre os procedimentos analíticos avaliados, sistema automatizado e o manual (convencional). A utilização de material marcado (K234SO4), teve como finalidade a validação do método de determinação de S-Total e isotópica de S nas amostras de solo. Com os resultados obtidos no experimento pode-se verificar que o processo de conversão de S-Orgânico à S-Inorgânico utilizando o método de oxidação alcalina, via seca, foi adequado. Com os resultados da determinação isotópica de S (% em átomos de 34S) do experimento empregando material enriquecido em 34S(k2SO4), pode-se calcular que o erro analítico foi em média 1,1 %. Este foi considerado baixo tendo em vista que o processo envolve varias etapas e dois procedimentos analíticos complexos / Sulphur in soil may be found under two basic forms; Inorganic-S and Organic-S. Sulphur under inorganic form (Sulphate-S) may be available to plant, however organic sulphur is responsible for 95 % of total sulphur in the most of soils. Aiming quantifies the available sulphur in soil, ammonium acetate plus acetic acid extractor solution was used. Efficiency of Organic-S oxidation to form Inorganic-S for Total-S determination in soil samples was evaluated applying oxidation reaction by wet and dried methods. A flow injection analysis (FIA) automatic system exploring multi-commutation and binary sample techniques was development for determination of Total-S and available Sulphate-S. Results of Total-S and available Sulphate were in agreement with analytical procedures evaluated, automatic and conventional systems. Use of labeled material (K234SO4) aimed to validate the method for Total-S and isotopic S determination in soil samples. Obtained results in experiments showed that the conversion process of Organic-S to Inorganic-S using alkaline oxidation reaction by dried method was appropriated. Based on results obtained in S isotopic determination (% in atoms of 34S) by applied experiment using material enriched on 34S(k2SO4), was possible calculate that the analytical error was about 1.1 %. This result was considered low considering quantity of involved steps in process and complexity of analytical process
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Efeito do tamanho médio de particulado sobre a conversão e o coeficiente global de taxa de reação na absorção de SO2 por calcário em reator de leito fluidizado / not availableSilva, Giovanilton Ferreira da 20 August 2001 (has links)
Neste trabalho estudou-se o efeito da granulometria do calcário na absorção de SO2 em batelada em reator de leito fluidizado borbulhante. Conversão e coeficiente global de reação foram estabelecidos a partir de condições simuladas, típicas de combustão em leito fluidizado. O sistema experimental foi constituído por um reator de 160 mm de diâmetro interno e altura de 450 mm. Utilizou-se granulometria estreita de dois tipos de calcários com diâmetros médios de 390, 462, 545, 650 e 770 μm. A areia de quartzo que compunha o leito tinha diâmetro igual ao do calcário. O ar foi aquecido por resistências elétricas e acrescido de frações de SO2, alcançado concentrações em torno de 1000 ppm. Os experimentos foram realizados com bateladas de 50 g de calcário, temperatura fixa de 850°C, e relação entre velocidades de fluidização e de mínima fluidização foi mantida 4/1. Os resultados mostram que a conversão variou entre 10 a 40% para o calcário magnesiano e 8 a 25% para o calcítico. O coeficiente global de taxa de reação aumentou com redução do diâmetro. O modelo de redução de dados não respondeu satisfatoriamente para partículas de 462 e 390 μm. / This work concerns the study of the effect of limestone particle size on S02 absorption in bench fluidized bed reactor plant. Conversion and global reaction rate coefficients were established for simulated conditions typical to fluidized bed combustion of coal. The reactor had an internal diameter of 160 mm and 450 high. The bed was fluidized with air containing a concentration of about 1000 ppm of S02. Narrows size distribution of two types of limestone with overage diameters of 390, 462, 545,650 and 770 mm. It were used sand of quartz that composed the bed had the same diameter of the limestone. The experiments were carried out on a batch mode introducing samples of 50 g limestone into the bed. The temperature of the process was fixed in 850ºC. The ration between gas fluidization velocity and minimum fluidization velocity was fixed about 4/1. The results show that the conversion varied among 10 to 40% for the magnesiano and 8 to 25% for the calcítico limestone. The global of reaction rate coefficient increased with reduction of diameter. The data reduction model did not answer satisfactorily for particles of 462 and 390 μm.
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Efeito do tamanho médio de particulado sobre a conversão e o coeficiente global de taxa de reação na absorção de SO2 por calcário em reator de leito fluidizado / not availableGiovanilton Ferreira da Silva 20 August 2001 (has links)
Neste trabalho estudou-se o efeito da granulometria do calcário na absorção de SO2 em batelada em reator de leito fluidizado borbulhante. Conversão e coeficiente global de reação foram estabelecidos a partir de condições simuladas, típicas de combustão em leito fluidizado. O sistema experimental foi constituído por um reator de 160 mm de diâmetro interno e altura de 450 mm. Utilizou-se granulometria estreita de dois tipos de calcários com diâmetros médios de 390, 462, 545, 650 e 770 μm. A areia de quartzo que compunha o leito tinha diâmetro igual ao do calcário. O ar foi aquecido por resistências elétricas e acrescido de frações de SO2, alcançado concentrações em torno de 1000 ppm. Os experimentos foram realizados com bateladas de 50 g de calcário, temperatura fixa de 850°C, e relação entre velocidades de fluidização e de mínima fluidização foi mantida 4/1. Os resultados mostram que a conversão variou entre 10 a 40% para o calcário magnesiano e 8 a 25% para o calcítico. O coeficiente global de taxa de reação aumentou com redução do diâmetro. O modelo de redução de dados não respondeu satisfatoriamente para partículas de 462 e 390 μm. / This work concerns the study of the effect of limestone particle size on S02 absorption in bench fluidized bed reactor plant. Conversion and global reaction rate coefficients were established for simulated conditions typical to fluidized bed combustion of coal. The reactor had an internal diameter of 160 mm and 450 high. The bed was fluidized with air containing a concentration of about 1000 ppm of S02. Narrows size distribution of two types of limestone with overage diameters of 390, 462, 545,650 and 770 mm. It were used sand of quartz that composed the bed had the same diameter of the limestone. The experiments were carried out on a batch mode introducing samples of 50 g limestone into the bed. The temperature of the process was fixed in 850ºC. The ration between gas fluidization velocity and minimum fluidization velocity was fixed about 4/1. The results show that the conversion varied among 10 to 40% for the magnesiano and 8 to 25% for the calcítico limestone. The global of reaction rate coefficient increased with reduction of diameter. The data reduction model did not answer satisfactorily for particles of 462 and 390 μm.
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Determinação isotópica de S (% em átomos de 34S) por espectrometria de massas em amostras de solo, a partir de S-Total e S-Sulfato disponível / Isotopic determination of S (% in atoms of 34S) by mass spectrometry in soil samples based on Total-S and available Sulphate-SAlexssandra Luiza Rodrigues Molina Rossete 31 January 2007 (has links)
O enxofre no solo pode ser encontrado em duas formas básicas como S-Inorgânico e S-Orgânico. O enxofre na forma inorgânica (S-Sulfato) pode estar prontamente disponível à planta, mas o enxofre orgânico é responsável por 95% do enxofre total na maioria dos solos. Com o objetivo de quantificar o sulfato disponível do solo utilizou-se como extrator solução de acetato de amônio em ácido acético. A eficiência da oxidação do S-Orgânico à S-Inorgânico, para determinação de S-Total em amostras de solo, foi avaliada com o emprego de métodos de oxidação por via úmida e seca. Para a quantificação do S-Total e S-Sulfato disponível foi desenvolvido um sistema automatizado de análise em fluxo (FIA) empregando multicomutação e amostragem binária. Os resultados das determinações de S-Total e de Sulfato disponível mostraram-se concordantes entre os procedimentos analíticos avaliados, sistema automatizado e o manual (convencional). A utilização de material marcado (K234SO4), teve como finalidade a validação do método de determinação de S-Total e isotópica de S nas amostras de solo. Com os resultados obtidos no experimento pode-se verificar que o processo de conversão de S-Orgânico à S-Inorgânico utilizando o método de oxidação alcalina, via seca, foi adequado. Com os resultados da determinação isotópica de S (% em átomos de 34S) do experimento empregando material enriquecido em 34S(k2SO4), pode-se calcular que o erro analítico foi em média 1,1 %. Este foi considerado baixo tendo em vista que o processo envolve varias etapas e dois procedimentos analíticos complexos / Sulphur in soil may be found under two basic forms; Inorganic-S and Organic-S. Sulphur under inorganic form (Sulphate-S) may be available to plant, however organic sulphur is responsible for 95 % of total sulphur in the most of soils. Aiming quantifies the available sulphur in soil, ammonium acetate plus acetic acid extractor solution was used. Efficiency of Organic-S oxidation to form Inorganic-S for Total-S determination in soil samples was evaluated applying oxidation reaction by wet and dried methods. A flow injection analysis (FIA) automatic system exploring multi-commutation and binary sample techniques was development for determination of Total-S and available Sulphate-S. Results of Total-S and available Sulphate were in agreement with analytical procedures evaluated, automatic and conventional systems. Use of labeled material (K234SO4) aimed to validate the method for Total-S and isotopic S determination in soil samples. Obtained results in experiments showed that the conversion process of Organic-S to Inorganic-S using alkaline oxidation reaction by dried method was appropriated. Based on results obtained in S isotopic determination (% in atoms of 34S) by applied experiment using material enriched on 34S(k2SO4), was possible calculate that the analytical error was about 1.1 %. This result was considered low considering quantity of involved steps in process and complexity of analytical process
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