Thesis (M. S.)--Pennsylvania State University, 1975. / Includes bibliographical references.

<p>Flertalet studier har påvisat ett samband mellan koncentrationen av partiklar ≤ 10µm i luftföroreningar och cardiovaskulär- och pulmonell morbiditet och mortalitet. Vid resektion, koagulering/bränning med diatermipenna under operationer alstras rök. Denna rök innehåller bland annat mutagena och carcinogena partiklar i inhalerbar storlek (partiklar ≤ 10µm).</p><p>Ett första syfte med denna studie var att kvantifiera den mängd ultra-fina partiklar (UFP) och partiklar ≤ 10µm som operationspersonal exponeras för i operationsrummet, vid användande av diatermi med mobilt rökutsug. Ett andra syfte var också att ta reda på om operations-personal exponeras olika mycket beroende på var i rummet de befinner sig, samt undersöka om partikelnivåerna skiljer sig på olika operationssalar. Partikelmätningar utfördes under 14 ortopediska operationer där diatermi med rökutsug använts.</p><p>Medelvärdena av UFP visar på relativt låga partikelkoncentrationer på höftprotes- och ryggoperationer, med mycket korta stunder av höga värden upp till ett maxvärde på 88 396pt/ml vid operationsområdet. Även partiklar i storleken 1-10µm låg inom låga nivåer och under gränsvärdena vid jämförelse med organisk damm. Resultaten i studien indikerar att personal som står vid operationssåret exponeras av högre partikelkoncentrationer av ultra-fina partiklar och partiklar 1-10µm än övrig personal, även vid användande av mobilt rökutsug. Vid jämförelse av partikelnivåer av ultra-fina partiklar på två olika operationssalar framkom det att på den sal med lägst antal luftväxlingar i operationsrummet, var partikelkoncentrationen signifikant högre.</p>

The study aimed at investigating the chemical composition and microstructure of raw iron ore from the deposits in Muko area (south-western Uganda). The quality of this iron ore was evaluated to establish its suitability to serve as a raw material for iron production. Samples were taken from the six hills of Muko ore deposits and tests carried out to establish their composition and properties. X-ray diffraction and scanning electron microscopy were employed in the investigation and chemical analysis performed to determine the compounds constituting the ore. The quality of this ore was compared to generalized world market standards and ores from other nations. It was found that Muko ore is a rich hematite grade with Fe content above 65%. It has little gangue (&lt;6% SiO2 and 3-4% Al2O3) and low contents of the deleterious elements (P ~ 0.02% and S &lt; 0.006%), which correspond to acceptable levels for commercial iron ores. / <p>QC 20130531</p> / Sustainable Technology Development in the Lake Victoria Region

Flertalet studier har påvisat ett samband mellan koncentrationen av partiklar ≤ 10µm i luftföroreningar och cardiovaskulär- och pulmonell morbiditet och mortalitet. Vid resektion, koagulering/bränning med diatermipenna under operationer alstras rök. Denna rök innehåller bland annat mutagena och carcinogena partiklar i inhalerbar storlek (partiklar ≤ 10µm). Ett första syfte med denna studie var att kvantifiera den mängd ultra-fina partiklar (UFP) och partiklar ≤ 10µm som operationspersonal exponeras för i operationsrummet, vid användande av diatermi med mobilt rökutsug. Ett andra syfte var också att ta reda på om operations-personal exponeras olika mycket beroende på var i rummet de befinner sig, samt undersöka om partikelnivåerna skiljer sig på olika operationssalar. Partikelmätningar utfördes under 14 ortopediska operationer där diatermi med rökutsug använts. Medelvärdena av UFP visar på relativt låga partikelkoncentrationer på höftprotes- och ryggoperationer, med mycket korta stunder av höga värden upp till ett maxvärde på 88 396pt/ml vid operationsområdet. Även partiklar i storleken 1-10µm låg inom låga nivåer och under gränsvärdena vid jämförelse med organisk damm. Resultaten i studien indikerar att personal som står vid operationssåret exponeras av högre partikelkoncentrationer av ultra-fina partiklar och partiklar 1-10µm än övrig personal, även vid användande av mobilt rökutsug. Vid jämförelse av partikelnivåer av ultra-fina partiklar på två olika operationssalar framkom det att på den sal med lägst antal luftväxlingar i operationsrummet, var partikelkoncentrationen signifikant högre.

Ozone is integral to tropospheric chemistry, and understanding the processes controlling its distribution is important in climate and air pollution contexts. The GEOS-Chem global chemical transport model and its adjoint are used to interpret the impacts of midlatitude precursor emissions and atmospheric transport on the tropospheric ozone distribution at middle and high northern latitudes. In the Arctic, the model reproduces seasonal cycles of peroxyacetyl nitrate (PAN) and ozone measured at the surface, and observed ozone abundances in the summer free troposphere. Source attribution analysis suggests that local photochemical production, ≤ 0.25 ppbv/day, driven by PAN decomposition accounts for more than 50% of ozone in the summertime Arctic boundary layer. In the mid-troposphere, photochemical production accounts for 30-40% of ozone, while ozone transported from midlatitudes contributes 25-35%. Adjoint sensitivity studies link summertime ozone production to anthropogenic, biomass burning, soil, and lightning emissions between 50N-70N. Over Alert, Nunavut, the sensitivity of mid-tropospheric ozone to lightning emissions sometimes exceeds that to anthropogenic emissions. Over the eastern U.S., numerous models overestimate ozone in the summertime boundary layer. An inversion analysis, using the GEOS-Chem four-dimensional variational data assimilation system, optimizes emissions of NOx and isoprene. Inversion results suggest the model bias cannot be explained by discrepancies in these precursor emissions. A separate inversion optimizes rates of key chemical reactions including ozone deposition rates, which are parameterized and particularly uncertain. The inversion suggests a factor of 2-3 increase in deposition rates in the northeastern U.S., decreasing the ozone bias from 17.5 ppbv to 6.0 ppbv. This analysis, however, is sensitive to the model boundary layer mixing scheme. Several inversion analyses are conducted to estimate lightning NOx emissions over North America in August 2006, using ozonesonde data. The high-resolution nested version of GEOS-Chem is used to better capture variability in the ozonesonde data. The analyses suggest North American lightning NOx totals between 0.076-0.204 Tg N. A major challenge is that the vertical distribution of the lightning source is not optimized, but the results suggest a bias in the vertical distribution. Reliably optimizing the three-dimensional distribution of lightning NOx emissions requires more information than the ozonesonde dataset contains.

No description available.

Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-24Bitstream added on 2014-06-13T21:01:18Z : No. of bitstreams: 1 pistori_ret_dr_jabo.pdf: 655530 bytes, checksum: 5dd6e06e56c9dd86e320aca408dfa634 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Esta tese esta organizada em dois capítulos. O capítulo I testou a hipótese de que o crescimento de Eichhornia crassipes, Pistia stratiotes e Salvinia molesta esta relacionado com a absorção de fosfato e de nitrogênio. Foi avaliado o efeito de diferentes concentrações de nutrientes sobre a taxa de crescimento e de absorção de ortofosfato (PPO4) e nitrogênio inorgânico total (NIT) em E. crassipes, P. stratiotes e S. molesta. As três espécies, quando cultivadas em baixa concentração de nutrientes apresentaram as maiores taxas de absorção tanto de P-PO4 quanto de NIT no período entre 0-5 dias, diferente do que ocorreu quando cultivadas em alta concentração, na qual as maiores taxas de absorção do P-PO4 ocorreram no período entre 0-5 dias e as maiores taxas de absorção de NIT para P. stratiotes ocorreram no período entre 5-10 dias e para E. crassipes e S. molesta no período entre 10-15 dias. Em baixa concentração, S. molesta obteve um ganho de massa 12,8 vezes menor que E. crassipes e 1,3 vezes menor que P. stratiotes e sua taxa de absorção de PPO4 no mesmo período foi semelhante a de E. crassipes e P. stratiotes. Padrão semelhante também foi observado em alta concentração, entretanto, apesar de apresentar maior taxa de absorção, S. molesta foi a espécie menos eficiente na remoção de nutrientes e a que menos estocou N e P, devido ao menor ganho de biomassa. E. crassipes e P. stratiotes apresentam crescimento vertical, o que favorece o maior ganho de biomassa e conseqüentemente maior taxa de remoção de nutrientes e estoque de N e P em sua biomassa. Os resultados permitem concluir que na aplicação para tratamento em wetlands, S. molesta, apesar de apresentar maior taxa de absorção pode ser menos eficiente. O capítulo II teve como objetivo testar o efeito de diferentes concentrações de fosfato na água sobre o crescimento e a composição química... / The thesis is organized in two chapters. The first chapter tested the hypothesis that the growth of Eichhornia crassipes, Pistia stratiotes and Salvinia molesta is related with the absorption of phosphate and nitrogen. It was studied the effect of different nutrient concentrations on the growth rate and orthophosphate (P-PO4) and total inorganic nitrogen (NIT) absorption rate in E. crassipes, P. stratiotes and S. molesta. The three species cultivated in low nutrient concentrations showed the highest absorption rate of P-PO4 and NIT between 0- 5 days. In high nutrient concentrations the highest absorption rate of P-PO4 for all species occurred between 0-5 days and the highest rate of absorption of NIT for P. stratiotes occurred between 5-10 days and for E. crassipes and S. molesta occurred between 10-15 days. The gain of mass of S. molesta in low concentration was 12.8 times minor than E. crassipes and 1.3 times minor then P. stratiotes and absorption rate in the same period were similar for the tree species. A similar pattern was observed in high concentration of nutrients. However, S. molesta have lower efficiency to absorb nutrients and have lower stock of N and P, due to the minor gain of biomass. E. crassipes and P. stratiotes showed vertical growth that provided high gain of biomass and consequently high uptake of nutrients and stock of N and P in the biomass. We concluded that S. molesta have lower efficiency in wetlands to treat effluents. In the chapter II we investigate the effect of different concentrations of phosphate in the water on the growth and the chemical composition of E. crassipes, P. stratiotes and S. molesta. The fully randomized experiment (4 treatment and 3 replicates) was conducted in the laboratory. The PPO4 concentration was different on the 4 treatment (< 0.005; 0.031; 0.31; 3.1 mg.L-1). The constant derivates from Michaelis Menten model that defined... (Complete abstract click electronic access below)

O objetivo deste trabalho visa analisar criticamente o processo de fabricação do arame galvanizado, discutindo a influência de variáveis, tais como: composição química do aço, velocidade dos fios na linha de galvanização e temperaturas associadas ao tratamento térmico, garantindo com isto um produto aderente as novas necessidades apresentadas pelo setor da avicultura que emprega o arame galvanizado BWG 18 na confecção de telas. A metodologia adotada envolveu as etapas de revisão da literatura e procedimento experimental D.O.E. (Design of Experiments), com coleta de amostras sob diferentes empregos (matéria prima) e condições operacionais (alteração de velocidades na linha de galvanização) e posterior realização de ensaios e análises de laboratório nas amostras coletas. Na etapa final foi realizado a avaliação e discussão dos resultados obtidos, identificando o produto galvanizado que melhor atende as propriedades mecânicas exigidas na fabricação de telas para o setor de avicultura. / The objective of this work aims at critically analyze the process of manufacture of the galvanized wire, arguing the influence of variables, such as: chemical composition of the steel, wire speed in the galvanizing line and temperatures associates to the heat treatment, ensuring with this an adherent product the new necessities presented for the poultry keeping that uses galvanized wire BWG 18 in the manufacturing of wire mesh. The adopted methodology involved the stages of revision of literature and experimental procedure D.O.E. (Design of Experiments), with acquisition of samples under different jobs (raw material) and operational conditions (alteration of speeds in the galvanizing line) and later accomplishment of assays and analyses of laboratory in the samples collections. In the final stage it was carried through the evaluation and quarrel of the acquired results, identifying the galvanized product that better takes care of the demanded mechanical properties in the manufacture of wire mesh for the poultry keeping sector.