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1
Fowler, Lesley, and n/a. "Meditation and mental health." University of Canberra. Education, 1986. http://erl.canberra.edu.au./public/adt-AUC20060710.130437.
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The claims of the traditional texts and teachers of Buddhist meditation include the enhancement of mental health.
Twenty five meditators sitting a ten day retreat in Vipassana and Metta meditation were measured on a compassion scale and an androgyny index. The androgyny index was used to measure mental health.
Compassion scores for all meditators increased slightly after the
retreat. Experienced meditators had significantly higher scores than
inexperienced meditators.
Regardless of previous experience, meditators with high
compassion scores significantly increased in androgyny after the
retreat. The traditional claims for the enhancement of mental health
are therefore supported by these results.
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Park, Eun Joo. "Metal Speciation, Mixtures and Environmental Health Impacts." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:23205169.
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Numerous applications of heavy metal have caused to their wide contamination in the environmental system and raised serious concerns over potential harmful effects on public health and the environment. Water, sediment, and dietary food are the main exposure media of heavy metal pollution and key determinants of adverse human and environmental health effects. Heavy metal(s) toxicity and speciation involve various mechanistic features with specific media and some of them are not clearly investigated. In particular, biological effects such as toxicity are not related to the total concentration of heavy metals in media, and many laboratory and field studies have supported this supposition. Organisms respond to the bioaccessible and bioavailable fraction of metals only, not the total concentration. The bioaccessibility and bioavailability of toxicants are dependent on chemical properties of the contaminant, the many exposure pathways, and temporal variability of these variables with respect to uptake by the target organism. Usually, bioavailable fractions are estimated using chemical or biological approaches. For this study, biological approaches were performed to better ascertain the toxic effects of heavy metals on organisms. A better understanding of bioaccessibility and bioavailability can be a useful tool in exposure and risk assessment. Therefore, this study presents experimental designs focusing on assessing of the bioaccessibility and bioavailability of metals in aquatic, benthic organisms and dietary food. This study also examines the role of metal mixtures on the adverse effects of metals.
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Bastos, Silvio Cesar. "Efeito do aquecimento por indução eletromagnetica de tubos sem costura utilizados em motores a diesel." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264397.
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Orientador: Sergio Tonini ButtonDissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Este trabalho apresenta um estudo sobre o efeito dos processos de recalque a frio e aquecimento por indução eletromagnética sobre as características da microestrutura e dureza do material de tubo de aço sem costura que é utilizado no transporte de fluxo de combustível em sistema de injeção de alta pressão. Por conduzir combustível, a característica de vedação é crítica para as interfaces de montagem destes tubos. Esta interface tem perfil cônico gerado pelo processo de recalque. A microestrutura obtida na região de vedação pode influenciar na dureza do material devido à conformação plástica ocasionada durante processo de recalque de perfil. Os valores de microdureza observados na região de recalque tendem a estar acima da dureza encontrada no material antes da conformação. Este acréscimo de dureza pode influenciar na vedação ocasionando vazamentos, caso o perfil cônico não tenha acomodação uniforme com o perfil da contra-peça, sendo esta o ""rail"" de distribuição ou a bomba de alta pressão de combustível. O processo de aquecimento por indução pode em condições controladas proporcionar alteração da microestrutura e dureza do material, conforme aquecimento e resfriamento desejados.
Abstract: This paper presents a study about the effect of cold upsetting and electromagnetic induction heating on microstructure and hardness characteristics of steel seamles pipe. This pipe studied is applied in fuel flow transport of high pressure fuel system. As fuel is transported the pipe sealing characteristic is critical on assembly interfaces of this pipe. This interface has conic profile produced at upsetting process. The hardness values observed on cold upsetting pipe has a trend to be higher than raw material. There microstructure changed can cause leakage if sealing contact area between conic profile of components has not accommodation enough, being high pressure pump or "rail". The hardness increase can reduce this sealing contact reducing deformation after tight-fitting. The induction heating process under controlled conditions can furnish change of microstructure and hardness material suitable for leak-tightness.
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
4
Barari, Farzad. "Metal foam regenerators : heat transfer and pressure drop in porous metals." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6366/.
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Open pore metal foams with moderate porosity (0.6 – 0.7) may be of interest as regenerators due to their high volumetric heat capacity and large specific surface area. Replication process is a low cost and simple foam manufacturing method which provides moderate porosity metal foams. Due to its simplicity, it provides many opportunities to investigate the effect of porosity, pore size and shape or their combination. In this study, this process was used to manufacture metal foams. A method, called vacuum-gas, was the standard method for manufacturing metal foams in the University of Sheffield Material Science and Engineering department. This method was further investigated and two new methods, gas-only and mechanical infiltration, were introduced. Based on the foams produced by these methods, the gas-only method was adopted due to its repeatability and quality. The method was further investigated by manufacturing eight more samples (1.4-1.7 mm pore size) under various infiltration pressures and the optimum infiltration pressures were found for manufacturing foams with pore size of 1-1.1 mm, 1.4-1.7 mm and 2.0-2.36 mm. A total of nine aluminium metal foams were manufactured for thermal and pressure testing. The manufactured foams had three different pore sizes, 1-1.1 mm (called Small samples), 1.4-1.7 mm (called Mid samples) and 2-2.36 mm (called Large samples). On average foams had porosity in the range of 0.62 – 0.65. Since this type of metal foams never been tested as a regenerator, two extra samples (a packed bed of 10000 2mm ball bearing and a packed bed of 100 layers of wire mesh No. 200) were made to compare with the manufactured foams and the results from other researchers. A test rig was built to test the pressure drop under steady state flow condition from 1 to 6.5 m/s (permeability based Reynolds number from 20 to 175). The extended Darcy-Forchheimer equation and a cubic velocity of Darcy-Forchheimer were used to measure the permeability and form drag of the samples. The results showed that the cubic velocity equation had a better prediction of the permeability and form drag. The Small samples had the lowest permeability and highest form drag coefficient for metal foams. The wire mesh sample had the lowest permeability and lowest form drag among the tested samples. In addition to steady state flow, samples pressure drop was also measured under oscillatory flow. A test rig was built to measure pressure drop and air instant velocity under oscillatory flow (1 to 19 Hz). The results showed that the oscillatory pressure drop was higher than steady state flow except for the Small samples which had higher pressure drop at steady state flow. The pressure drop for the wire mesh sample was measured to compare with other researchers data and a good agreement was observed with some of the published data. Moreover, the instant air velocity was measured by a hot-wire anemometer inside the connecting tube between the sample holder and the compressor. The results showed that the air velocity behaved like a turbulent flow during the acceleration and deceleration period. A single-blow test rig was designed and manufactured to measure thermal performance of the samples. To estimate the average heat transfer coefficient of the samples, several types of the single-blow models were studied and the extended Schumann-Hausen model was implemented for predicting the samples’ outlet air temperature history. Two matching techniques, maximum gradient and direct curve matching were used to match the experimental and modelled outlet temperatures history to estimate samples’ NTU and average heat transfer coefficient. The results showed that NTU increased with decreasing of pore size. Based on mass flow rate Mid samples had the highest h, however the difference between the metal foam samples were insignificant. The foam samples had higher heat transfer coefficient than the ball bearing sample but the wire mesh sample had the highest heat transfer coefficient. The heat transfer results for the wire mesh and ball bearing samples were compared with published data and good agreements were observed.
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Ngule, Chrispus M. Jr. "In Vitro Adsorption of Heavy Metals Using Metal-Organic Frameworks." Youngstown State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1597664070125999.
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Lee, Lin. "The effect of flow rate, spray distance and concentration of polymer quenchant on spray quenching performance of CHTE and IVF probes." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-050205-151345/unrestricted/LinLeeThesis.pdf.
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Severance, Jennifer Jurado Eve Susan Brown. "A survey of collaborative efforts between public health and aging services networks in community health centers in Texas." [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/permalink/meta-dc-10984.
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Tkaczyk, Cathy. "Ions released from metal-on-metal hip implants: «in vitro» and «in vivo» investigations." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86703.
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Studies have shown that Co and Cr particles and ions can enter the bloodstream and accumulate in tissues and organs of patients after metal-on-metal (MM) total hip arthroplasty (THA). These ions can generate reactive oxygen species (ROS) that can be deleterious for cells. We first assessed the biological effects of Cr(VI), Co(II), and Cr(III) by testing their effect on antioxidant enzymes (SODs, CAT, GPx, HO-1) that represent a primary defense system against ROS. We demonstrated that Cr(VI) induced the protein expression (translation) of antioxidant enzymes, whereas it had no effect on the mRNA expression (transcription). Co(II) induced the expression of both protein and mRNA of HO-1 only. Cr(III) had no effect on the activity of these enzymes. We then suggested that a difference in molecular structure may be at the origin of their differential effects and showed that Cr(III) can form precipitable complexes, whereas Co(II) and Cr(VI) cannot form complexes in the same experimental conditions. These Cr(III) complexes, formed in simulated-physiological fluids, were constituted by an organic phase (amino acids, phosphate) tangled with an inorganic phase (Cr, Ca, Na). Interestingly, these Cr(III) complexes interacted only with albumin in presence of fetal bovine serum, whereas they interacted with 8 different human serum proteins in presence of human serum. The interaction of Cr(III) complexes with serum proteins affect their internalization by macrophages, complexes formed with human serum being more easily internalized than those bound to bovine proteins. Lastly, results suggested that the levels of Co and Cr ions in patients with MM THA are not sufficient to induce significant oxidative stress in the blood of these patients, bringing optimism over concern for the long term biological effects of Co and Cr ions released from metal-metal bearings. In conclusion, this thesis gives very valuable information on the biological effects of Cr and Co ions and gives insight iDe nombreuses études ont montré que les particules et ions métalliques (Cr(III), Co(II) et Cr(VI)) générés par l'usure de prothèses de hanche métalliques (PHM) se retrouvent dans le flux sanguin des patients et s'accumulent également dans leurs tissus et leurs organes. Ces ions peuvent génèrer des radicaux libres qui peuvent à leur tour être nocifs pour la cellule. Nous avons déterminé les effets de ces ions sur les enzymes antioxidantes (SODs, CAT, GPx, HO-1) qui représentent la première ligne de défense cellulaire contre les radicaux libres. Nos travaux ont révélé que le Cr(VI) induit l'expression de ces protéines (traduction) mais non l'expression de leur ARNm (transcription). Le Co(II) induit l'expression de la proteine et de l'ARNm de HO-1 seulement alors que le Cr(III) n'a aucun effet sur l'expression de ces enzymes. Nous avons par la suite suggéré, que la structure moléculaire de ces ions pouvait avoir une influence sur leurs différents effets. Les résultats ont montré que le Cr(III) formait des complexes constitués d'une partie organique (acides aminés et phosphates) et d'une partie inorganique (Cr, calcium et sodium), alors que ni le Co(II), ni le Cr(VI) ne formaient de complexes dans les mêmes conditions expérimentales. En présence de sérum bovin fétal, les complexes de Cr(III) pouvent se lier seulement à l'albumine, alors qu'en présence de sérum humain, ces mêmes complexes intéragissent avec 8 protéines de nature differente. Cette intéraction avec les protéines humaines semble augmenter l'internalisation des complexes par les macrophages. Finalement, les résultats démontrent que la concentration d'ions Co et Cr présents dans le sang de patients portant une PHM est insuffisante pour induire un stress oxydant et apportent un souffle optimiste sur les effets à long terme des ions métalliques chez les patients. Dans son ensemble ce projet apporte de nouveaux éléments de connaissances sur les effets biologiq
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Broadway, Andrew. "Development of methodologies for soil metal bioaccessibility and human health risk." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/16948.
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Between 1830 and 1968 Glasgow was home to one of the world’s largest producers of Cr-based chemicals. Chromite ore processing residue (COPR) arising from the factory was used as infill material across large areas of SE Glasgow, resulting in widespread land contamination with Cr(VI), a known human carcinogen of significant mobility. This thesis presents the results of a research project into the bioaccessibility of Cr in Glasgow soils, using a physiologically based extraction test (PBET). 27 Samples were analysed, four of which had a Cr concentration above the residential SGV (200 mg/kg). Two samples where identified with a sizeable Cr(VI) concentration, 1485 ± 24 and 171 ± 5 mg/kg, respectively. Bioaccessible Cr was significantly less than the total concentration, being an average 5% of the total concentration. One sample had a notably high Cr bioaccessibility, at 1156 ± 32 mg/kg. This sample, from Rutherglen, was the only one to exceed assessment criteria, and as such pose a potential risk to human health. The solid phase distribution was also assessed, making it possible to identify the likely mineral sources of bioaccessible Cr within a sample. In the majority of samples Cr was associated with Fe oxide phases, resulting in a low bioaccessibility. Two samples had a sizeable amount of Cr associated with clay and carbonate phases, which have less acid stability, resulting in a higher bioaccessibility (1156 ± 32 and 116 ± 2 mg/kg). A carbonate phase, unique to samples from sites with known history of COPR disposal, was also identified. This had a large amount of associated Cr, suggesting it was derived from the COPR.
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Gomez, Steven David Jenkins Sharon Rae. "Culture and mental health help-seeking attitudes in Mexico." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3670.
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Scherbarth, Andrew J. Critelli Joseph W. "Psychological abuse and health what role does forgiveness play? /." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3918.
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Cudhea, Maia Christine Cready Cynthia M. "Topical content in sexuality education and sexual health outcomes." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-5189.
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LeCoultre, T. D., and Phillip R. Scheuerman. "A Metal-Analysis and Risk Assessment of Heavy Metal Uptake in Common Garden Vegetables." Digital Commons @ East Tennessee State University, 2001. https://dc.etsu.edu/etsu-works/2927.
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Starr, David E. "Microcalorimetric heats of adsorption, surface residence times and sticking probabilities of metals on metal-oxide, and silicon substrates /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/8492.
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Leung, Chak-cheong. "Trace metals in sharks' fins : potential health consequences for consumers /." View the Table of Contents & Abstract, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39602230.
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梁澤昌 and Chak-cheong Leung. "Trace metals in sharks' fins: potential health consequences for consumers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B45013767.
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Avendt-Reeber, Mary M. D. "Chronic Kidney Disease and Heavy Metal Exposure in Children." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504873108060796.
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Pei, Xing. "Copper-based Point-of-care Sensor for Heavy Metal Determination in Public Health." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439309640.
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Link-Malcolm, Jessica Kelly Kimberly. "Health message framing motivating cardiovascular risk factor screening in young adults /." [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-9066.
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Loxham, Matthew. "The potential health effects of transition metals in particulate air pollution." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/387176/.
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Rahman, Aminur. "Bioremediation of Toxic Metals for Protecting Human Health and the Ecosystem." Doctoral thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-51436.
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Heavy metal pollutants, discharged into the ecosystem as waste by anthropogenic activities, contaminate drinking water for millions of people and animals in many regions of the world. Long term exposure to these metals, leads to several lethal diseases like cancer, keratosis, gangrene, diabetes, cardio- vascular disorders, etc. Therefore, removal of these pollutants from soil, water and environment is of great importance for human welfare. One of the possible eco-friendly solutions to this problem is the use of microorganisms that can accumulate the heavy metals from the contaminated sources, hence reducing the pollutant contents to a safe level. In this thesis an arsenic resistant bacterium Lysinibacillus sphaericus B1-CDA, a chromium resistant bacterium Enterobacter cloacae B2-DHA and a nickel resistant bacterium Lysinibacillus sp. BA2 were isolated and studied. The minimum inhibitory concentration values of these isolates are 500 mM sodium arsenate, 5.5 mM potassium chromate and 9 mM nickel chloride, respectively. The time of flight-secondary ion mass spectrometry and inductively coupled plasma-mass spectroscopy analyses revealed that after 120 h of exposure, the intracellular accumulation of arsenic in B1-CDA and chromium in B2-DHA were 5.0 mg/g dwt and 320 μg/g dwt of cell biomass, respectively. However, the arsenic and chromium contents in the liquid medium were reduced to 50% and 81%, respectively. The adsorption values of BA2 when exposed to nickel for 6 h were 238.04 mg of Ni(II) per gram of dead biomass indicating BA2 can reduce nickel content in the solution to 53.89%. Scanning electron micrograph depicted the effect of these metals on cellular morphology of the isolates. The genetic composition of B1-CDA and B2-DHA were studied in detail by sequencing of whole genomes. All genes of B1-CDA and B2-DHA predicted to be associated with resistance to heavy metals were annotated. The findings in this study accentuate the significance of these bacteria in removing toxic metals from the contaminated sources. The genetic mechanisms of these isolates in absorbing and thus removing toxic metals could be used as vehicles to cope with metal toxicity of the contaminated effluents discharged to the nature by industries and other human activities.
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O'Callaghan, Dana M. Chandler Cynthia K. "Exploratory study of animal assisted therapy interventions used by mental health professionals." [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-6068.
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Carvalho, Antonio Rogerio Torres. "Estudo da influencia da agitação e da severidade de tempera do meio de resfriamento na determinação de velocidades criticas de tempera." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264702.
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Orientador: Valdemar Silva LealDissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Estuda-se a influência da variação da agitação e da severidade de têmpera do meio de resfriamento sobre as curvas e taxas de resfriamento durante o processo de têmpera do aço. Os ensaios foram realizados com amostras dos aços 1045, 8620 e 8640, temperadas em água e salmoura, promovendo-se a variação do estado de agitação do refrigerante. Os dados apontam para variação da taxa de resfriamento máxima de 27,65% a 110,09% e uma diminuição nos tempos de resfriamento de 7,83% a 63,25%, para os três materiais estudados, com o aumento da agitação do meio. Verificam-se ainda, ganhos nas taxas e tempos de resfriamento com a variação da severidade de têmpera pela troca do meio, água por salmoura, da ordem de 73,27%, sem agitação do meio, e diminuição do tempo de resfriamento em aproximadamente 20%. Os dados ainda demonstram ganhos no tempo e nas taxas de resfriamento devido ao aumento do percentual de carbono no aço, quando se compara os dados obtidos para as amostras dos aços 8620 e 8640
Abstract: Study about the influence of the agitation range and quench severity of the quenchant on cooling times and rates during the quench. The assays were accomplished with samples of steel 1045, 8620 and 8640, water and brine quenched, by increasing the agitation of the quenchant. The data show a rise in the maximum cooling rates of the 27.65% - 110%, and a reduction in the times of cooling of the 7.83% - 63.25%, on the three materials studied, with the increase of the agitation of the quenchant. They were verified too, a gain in the cooling rates and times with the variation of the quenchant severity, water to brine, of 73.27%, without agitation, and reduction of cooling time in approximately 20%. The data still show a gain in the cooling time and rates caused by the percentage of carbon increase on the steel, when be compared with the data scored in the samples of steel 8620 and 8640
Mestrado
Instrumentação e Controle Industrial
Mestre Profissional em Engenharia Mecanica
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Chen, Haihan. "Heterogeneous chemistry and photochemistry of metal-containing aerosols and their impacts on atmospheric chemistry, metal mobilization, biogeochemical cycles and human health." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/3275.
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Atmospheric aerosols have significant impact on the chemical balance of the atmosphere, biogeochemical cycles, the Earth's climate and human health. Although extensive studies have been performed to explore these effects, there is still considerable uncertainty regarding the global impacts of atmospheric aerosols.
For example, understand heterogeneous photochemistry on aerosols may be crucial to accurately predict the impact of aerosol loadings on atmospheric chemistry, yet few studies have been conducted. In this dissertation research, laboratory studies were performed to investigate heterogeneous photoreactions of HNO3 and O3 on typical components of metal containing aerosols. Results indicate that the presence of irradiation has the potential to change the reaction mechanism, kinetics, reaction extent, products, and product partitioning. The presence of water at different relative humidity also plays a key role in the rates of these reactions and the product distribution.
Increasing evidence has suggested that anthropogenic aerosols play a more important role in supplying soluble iron into open ocean water compared with mineral dust. Dissolution experiments to simulate atmospheric processing were performed to compare iron mobilization abilities of coal fly ash with Arizona test dust, a model for mineral dust aerosol. Results indicate that coal fly ash spheres, which is mainly composed of aluminosilicate glass, are unstable and disintegrate into irregular fragments during simulated cloud processing. The disintegration of spherical fly ash facilitates the release of iron and thus iron mobilization. In contrast, aluminosilicate mineral as the main component of Arizona test dust is relative stable and thus shows no significant change of morphology during simulated atmospheric processing. The iron solubility strongly depends on the source material, surface pH, types of acidic media, and the presence of solar irradiation.
Heavy metals in the environment have a negative effect on human health. A study on Pb mobilization from PbO particles following exposure to NO2 shows interaction of PbO particles with NO2 leads to an increase in Pb dissolution. These results point to the potential importance and impact that heterogeneous chemistry with trace gases can have on increasing solubility and therefore the mobilization of heavy metals such as lead in the environment.
Furthermore, as a transition metal, iron is capable of generating reactive oxygen species and contributing to oxidative stress. Collaboration work indicates that size and surface area of iron nanoparticles play a role in affecting bacteria growth, pathogenicity, and impairing the AMP activity. Nanoparticles, especially the smaller particles with large surface areas, may be harmful to human health as it relates to individuals susceptible to bacterial infections and/or colonization.
This thesis summarizes the above studies in Chapter 3 to Chapter 7. The research described herein provides a number of important issues where further studies are warranted. The last chapter suggests future directions for laboratory studies that have the potential to make an important contribution on understand the global impacts of atmospheric aerosols and heterogeneous chemistry.
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Chen, Xuehui. "Accumulation of heavy metals and organochlorine pesticides in human milk and adipose tissues, and its health concerns." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/779.
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Amin, Iftekhar Ingman Stanley R. "Retiring in a foreign land health care issues of US retirees in Mexico /." [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-9801.
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Penna, Alessandro de Souza. "AVALIAÇÃO DA CONCENTRAÇÃO DE METAIS PESADOS NO ENTORNO DE MORRINHOS GO UMA ANÁLISE MULTIELEMENTAR EM SEDIMENTO DE CORRENTE E ÁGUA." Pontifícia Universidade Católica de Goiás, 2008. http://localhost:8080/tede/handle/tede/3070.
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Previous issue date: 2008-03-14The work, conducted in Morrinhos city, state of Goiás, Brazil, aimed to evaluate the concentration of heavy metals in the environment drainages in the lake located at its urban area, in the ETA - Estação de Tratamento de Água (an water treatment station) of SANEAGO (the state company responsible for water treatment and supply), and also in five households. All the work was done through an analysis multi-elemental by using twenty-eight samples of surface water and running sediment. This evaluation aimed to raise the possible natural and anthropogenic environmental contamination, in order to relate them to the people healthy. It was obtained the water physical-chemical patterns (by analyzing dissolved oxygen, pH, turbidity and conductivity), which were duly represented through maps of distribution. It was performed the chemical analysis on the samples of running water and sediment through the methods of AA, ICP-OES, ICP-MS and Liquid Chromatography. From the results obtained and statistically treated were made four correlation matrices from each sample, as defined the geochemical of each matrice and developed others sixty seven selected maps for the chemical distribution. The analysis of the results in running sediment showed high concentrations for Cd, Cr and Sb. In the analysis of the results in surface water were found abnormal results for the elements Ag, Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Mg, Ni, Pb, Sb and V. It was observed that, each greater the distance of sampling points from its source (near to the urban area), greater the environmental impacts caused by the anthrop action. Such impacts are due to the fact of drainages being used for recreation and leisure, irrigation of crops, gardens and orchards, in addition the water is been used as containers of sewage. The results obtained show an environment risk situation which can jeopardize the healthy of the people, who use the water on the region.
O trabalho, realizado no município de Morrinhos - GO, objetivou avaliar a concentração de metais pesados em drenagens do entorno, no lago existente em sua área urbana, em sua Estação de Tratamento de Água (ETA) da SANEAGO e também em cinco residências através de uma análise multielementar em vinte e oito amostras de água superficial e sedimento de corrente. Esta avaliação visou levantar as possíveis contaminações ambientais, sejam naturais ou antrópicas , a fim de relacioná-las com a saúde. Foram determinados os padrões físicoquímicos da água (oxigênio dissolvido, pH, turbidez e condutividade) que foram devidamente representados através dos mapas de distribuição. Foram realizadas as análises químicas nas amostras de água e sedimento de corrente, através dos métodos de AA, ICP-OES, ICP-MS e Cromatografia Líquida. A partir dos resultados obtidos e estatisticamente tratados foram confeccionadas quatro matrizes de correlação pertinentes a cada tipo de amostra, definidas as associações geoquímicas de cada matriz e desenvolvidos outros sessenta e sete mapas de distribuição dos elementos químicos selecionados. A análise dos resultados em sedimento de corrente mostraram altas concentrações para Cd, Cr e Sb. Na análise dos resultados em água superficial foram encontrados resultados anômalos para os elementos Ag, Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Mg, Ni, Pb, Sb e V. Observou-se com isso que, quanto maior a distância dos pontos de amostragem de sua nascente, e maior é a proximidade com a área urbana, maiores também são os impactos ambientais causados pela ação antrópica. Tais impactos devem-se ao fato das drenagens serem utilizadas para recreação e lazer, irrigação de plantações, hortas e pomares, além de serem recipientes de esgotos. Os resultados obtidos evidenciam uma situação de risco ambiental que pode comprometer a saúde da população que faz uso constante das águas da região.
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McShane, Heather. "Metal oxide nanoparticle chemistry and toxicity in soils." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117105.
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Metal oxide nanoparticles (MONPs) are increasingly being incorporated in domestic and industrial products. They are expected to pass into waste water treatment facilities, and may inadvertently be applied in biosolids to agricultural soils. Very few nanotoxicity studies have been conducted in soils and the risk that MONPs pose to soil organisms are poorly understood. The aim of this study was to investigate the behaviour and effects of two MONPs with different solubilities on terrestrial organisms in soils. Exposure of earthworms to soils amended with up to 10,000 mg/kg nano-sized TiO2, a virtually insoluble nanomaterial, resulted in no adverse effects on earthworm population parameters such as survival or reproduction. Earthworms avoided nano-TiO2 amended soils, but only at nanoparticle concentrations higher than those expected for agricultural soils. The mechanisms resulting in the avoidance response, and nano-TiO2 transformations in soils, could not be further investigated because techniques to track nanoparticles in complex media are lacking. Subsequent studies focused on a sparingly soluble nanomaterial, nano-CuO, which releases Cu2+ ions as it dissolves. To identify nanoparticle-specific effects on organisms, the effects of the Cu2+ ions must be determined but little is known about the effect of nano-CuO on Cu2+ activity in soils. Tests revealed that Cu2+ activity in nano-CuO amended soils increased over a 56 d period, but were not comparable to those in soils amended with similar concentrations of micrometer-sized CuO or Cu(NO3)2, which are commonly used as treatments to control for the effects non-nanosized Cu in nanotoxicity tests. These results have implications for the design of experiments that test effects of dissolving particulates. A subsequent barley growth test demonstrated that there was no significant difference in plant growth or shoot Cu concentrations between soils amended with nano-CuO, micrometer-sized CuO or Cu(NO3)2 once growth was normalised to Cu2+ activity. These results demonstrate that release of metal ions can play an important role in toxicity of soluble metal-based nanoparticles and highlight the importance of direct measurement of potentially toxic products of nanoparticle dissolution. There was no evidence of nanoparticle-specific toxicity under the conditions studied either for earthworms exposed to nano-TiO2 or barley exposed to nano-CuO. The study highlighted some of the challenges of understanding the fate and effects of nanomaterials in soils, including the lack of techniques to track nanomaterials in complex media and the difficulty in designing toxicity tests that control for temporal changes to both nanoparticles and soils.Les nanoparticules des oxydes de métaux (MONP) sont davantage incorporés dans les produits domestiques et industriels. Une importante proportion de ces nanoparticules est susceptible de se retrouver dans les usines de traitement d'eaux usées et d'être épandue sur les terres agricoles sous forme de biosolides. Dû au fait que peu de recherches sur la nanotoxicité ont été faites dans les sols, le risque que pose ces MONP aux organismes du sols est peu connu. Le but de cette étude est donc d'observer la réaction et les effets de deux MONP de solubilité différente dans des sols agricoles et artificiels. L'exposition des vers de terre dans des sols amendés avec jusqu'à 10,000 mg par kg de sol de nano-TiO2, un nanomatériel pratiquement insoluble, n'a causé aucun effet sur leur survie ou leur reproduction. Les vers de terre n'ont évité les sols modifiés de nano-TiO2, qu'à des concentrations de nanoparticules beaucoup plus élevées que celles attendues dans les sols agricoles. Les mécanismes impliqués dans la réponse d'évitement et les transformations de nanoTiO2 dans les sols n'ont pu être étudiés plus à fond par manque de techniques développées pour suivre les nanoparticules dans les médias complexes. Dans les recherches subséquentes, un nanomatériel de très faible solubilité, le nano-CuO, qui relâche des ions Cu2+ au fur et à mesure qu'il se dissout, a été choisi comme matériel d'intérêt. Afin d'identifier les effets spécifiques des nanoparticules sur des organismes, les effets du Cu2+ doivent être déterminés. Cependant, peu est connu sur l'activité du Cu2+ dans les sols traités avec des nano-CuO. Les recherches ont démontré que l'activité de Cu2+ a augmenté durant une période de 56 jours pour les sols amendés de nanoparticules de CuO mais cette augmentation ne s'est pas produite, à des concentrations égales, pour des sols enrichis de CuO de diamètre micrométrique ou même de sels de Cu(NO3)2 ; ces deux derniers traitements sont souvent utilisés comme tests contrôles lors d'études de nanotoxicité. Ces résultats ont des implications pour la conception des expériences pour évaluer les effets sur la dissolution des particules. Une étude ultérieure sur la croissance d'orge a démontré qu'il n'y avait aucune différence significative dans la croissance des plantes ou des concentrations de Cu dans les feuilles entre les sols modifiés avec du nano-CuO, CuO de taille micrométrique ou le Cu(NO3)2 une fois que les données furent normalisées en activité de Cu2+. Ces résultats ont démontré que la dissolution d'ions de métaux peut jouer un rôle important sur la toxicité des nanoparticules. Ils soulignent aussi l'importance de mesurer directement la concentration de produits de la dissolution de nanoparticules. Il n'y avait aucune évidence de toxicité spécifique aux nanoparticules sous les conditions étudiées pour les vers de terre soumis au nano-TiO2 ou pour l'orge soumis au nano-CuO. Cette étude a révélé certaines lacunes de compréhension dans le comportement du nanomatériel ajouté aux sols, des difficultés de tenir compte des changements temporels des nanoparticules et des sols ainsi que le manque de techniques disponibles pour suivre les nanoparticules dans les médias complexes.
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Reed, Linda E. Newsom Ron. "Determining the relationship between motivation and academic outcomes among students in the health professions." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3624.
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Camargo, Iara Maria Carneiro de. ""Estudo da influência do coeficiente de partição de metais no solo de Figueira, Paraná, no cálculo de risco à saúde humana, utilizando o modelo C-Soil"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-18102007-161220/.
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Estudos de coeficiente de partição mostram que o valor de Kp do metal pode variar ordens de grandeza conforme as características físico-químicas do solo. Portanto, o Kp é um parâmetro sensível no modelo de avaliação de risco à saúde humana, e normalmente é um valor nominal adotado por agências ambientais que pode não representar adequadamente o solo em estudo e implicar erros no cálculo do risco. Este trabalho tem como objetivos: avaliar a contaminação do solo adjacente à usina termoelétrica de Figueira por metais tóxicos; determinar o Kp dos metais As, Cd, Co, Cr, Cu, Mo, Ni, Pb e Zn no solo pela razão entre a concentração do metal obtida por digestão com HNO3 concentrado e a concentração do metal obtida por extração com EDTA 0,05 mol L-1 (KpEDTA) ou Ca(NO3)2 0,1 mol L-1 (KpCa(NO3)2); e avaliar a influência do uso dos diferentes valores de Kp no modelo de avaliação de risco à saúde humana C-Soil no cálculo do risco. As principais conclusões foram: os metais contaminantes do solo de Figueira foram As, Cd, Mo, Pb e Zn, e o As foi o elemento mais crítico; tanto o valor de KpCa(NO3)2 quanto o de KpEDTA poderiam ser utilizados no cálculo do risco à saúde humana, no caso de Figueira, exceto para o Pb, mas o KpEDTA seria mais recomendado, por apresentar valores com menor dispersão; os valores nominais de KpCSoil dos metais poderiam ser utilizados para o cálculo de risco à saúde humana no caso de Figueira, ou seja, não teria necessidade de se determinar valores de Kp locais (KpEDTA e KpCa(NO3)2), exceto para o Pb.Studies of partition coefficient show that Kp values of metals can vary orders of magnitude according to the soil physical-chemistry characteristics. Therefore, the Kp is a sensible parameter in human health risk assessment model. In general, a default value is adopted by environmental agencies and often it is not represent suitably the soil studied and can cause errors in the risk calculation. The objectives of this work are: evaluate the heavy metals soil contamination around the Figueira coal-fired power plant; determine the metal Kp of As, Cd, Co, Cr, Cu, Mo, Ni, Pb and Zn in soil by the ratio between the metal concentration obtained by concentrate HNO3 digestion and the metal concentration obtained by extraction with EDTA 0,05 mol L-1 (KpEDTA) or Ca(NO3)2 0,1 mol L-1 (KpCa(NO3)2); and evaluate the influence of the application of different Kp values in human health risk assessment C-Soil model in risk calculation. The main conclusions of the present study were: As, Cd, Mo, Pb e Zn were the Figueira soil metal contaminants, being As the pollunt of major human health concern; either KpCa(NO3)2 or KpEDTA values could be used for human health risk calculation, in Figueira case, except for Pb, and the KpEDTA values were preferably recommended due to the less dispersion of their values; the KpCSoil metals default values could be applied for the human health risk calculation in Figueira case, in other words, it would not have necessity to determine Kp values of region (KpEDTA and KpCa(NO3)2), except to Pb.
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Zhang, Jinming. "Mixed Metals Exposure, Cardiac Autonomic Responses, Inflammation and DNA Methylation." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:27201714.
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Background: welders are often exposed to various types of metals from the welding fumes and they also have high risks of cardiac autonomic dysfunction. Knowing the hazardous components within metals mixture as well as understanding the potential underlying mechanisms is essential for environmental and occupational regulations. Objective: to identify metal components which are associated with cardiac autonomic responses, as measured by two novel markers -acceleration capacity (AC) and deceleration capacity (DC); to examine whether inflammation mediates effects of metals exposure on AC/DC changes; to identify epigenetic variants which are associated with AC/DC changes. Methods: we collected urine, blood and electrocardiogram (ECG) samples from 75 welders over six sampling occasions between June 2003 and June 2012. Urinary concentrations of 16 types of metals were determined. Blood serum samples were analyzed for inflammatory cytokines levels including CRP, IL-2, IL4, IL6 and IL8. AC and DC values were quantified from ECG recordings. Firstly, we used linear mixed-effects models with Lasso to identify hazardous metals that were significantly associated with AC or DC changes. We fitted the co-pollutants model with “selected” metals in the linear mixed model to estimate the exposure-response relationship. Then, we conducted a mediation analysis to examine whether inflammatory cytokines mediated the effects of metals exposure on AC or DC changes. We report both direct and indirect effects in single pollutant model as well as co-pollutants models. Finally, we conducted the epigenome-wide association study (EWAS) to identify epigenetic variants that were associated with AC or DC changes. Results: we observed negative associations between urinary mercury and chromium concentrations with both DC and AC changes. Indirect effects of metals exposure on AC or DC through inflammation pathway were not significant. We identified GPR133 gene at which methylation level changes were associated with DC values. Conclusion: metals exposures are associated with impaired cardiac autonomic functions. Our study did not provide evidence that these effects were mediated through inflammation pathway. However, DNA methylation of specific genes may be a potential pathway linking environmental and occupational pollutants exposure and alterations in cardiac autonomic responses.
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Byrne, Patrick. "Contaminant hydrogeochemistry and aquatic ecosystem health at abandoned metal mines : the Afon Twymyn, central Wales." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/6174.
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Following the decline of the UK metal mining industry by the 1920s, over 3,000 abandoned metal mines exist in England and Wales. Contaminated drainage from this historical industry causes approximately 20% of all water quality failures in England and Wales. In this thesis, a holistic geographical approach, incorporating aspects of hydrology, hydrogeochemistry and freshwater ecology, is employed to investigate the hydrological, sedimentological and ecological impacts of the abandoned Dylife lead/zinc mine on the Afon Twymyn (central Wales). Examination of river sediment quality highlights the need for measurements of the quality of this component of the river ecosystem and, in particular, measurement of bioavailable as opposed to total metals. The majority of heavy metals in bed sediments of the Afon Twymyn exist in highly mobile geochemical phases, potentially posing serious threats to ecological integrity. Significant metal flushing occurred during flood events at Dylife mine and a distinct seasonal pattern was observed with greater levels of flushing occurring during flood events in the summer months. It is suggested that investigations of contaminant/ecosystem relations and potential remediation strategies should include high-resolution temporal sampling of river water chemistry under conditions of flood flow. Paradoxically, a range of biological indices failed to identify significant negative impacts of metal mine contaminants on macroinvertebrate communities, suggesting there is little contamination of the river ecosystem. However, Canonical Correspondence Analysis did identify significant differences in community structure between polluted and unpolluted river stretches, suggesting that standard unimetric biological indices might only be successful in identifying impacts at the most severely polluted mine sites. It is suggested that the ecological approach of the European Union Water Framework Directive to the assessment of river ecosystem status may not yield an accurate representation of contamination in rivers such as the Afon Twymyn where contamination by mining is moderate, circum-neutral and the mining operation is long abandoned.
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Chilelli, Sean Kelty. "Structural health monitoring with fiber Bragg grating sensors embedded into metal through ultrasonic additive manufacturing." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563529169604482.
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Al-Meshari, Abdulaziz I. "Metal dusting of heat-resistant alloys." Thesis, University of Cambridge, 2008. https://www.repository.cam.ac.uk/handle/1810/217872.
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Metal dusting leads to disintegration of such alloys as iron and nickel-based into a “dust” of particulate metal, metal carbide, carbon, and/or oxide. It occurs in strongly carburising environments at 400-900°C. Literature survey has shown that alloys behave differently in metal dusting conditions based on their composition and the environment. Metal dusting mechanisms for iron and nickel-based alloys have been proposed but, nevertheless, have not been agreed upon and numerous modifications to them have been suggested. Further adding to the complexity, the mechanisms were found to have differed due to operating condition alterations. In view of that, this research was carried out to gain a better understanding of metal dusting process(s) by evaluating the performance of heat-resistant alloys, namely KHR35C HiSi© (HP), KHR45A LC© (35Cr-45Ni), and UCX©, in metal dusting conditions. HP, which is an iron-based alloy, was modified by adding more silicon in order to improve its resistance through the development of SiO2 at the surface. The carbon content in the nickel-based alloy, 35Cr-45Ni, was lowered to delay the attack onset by accommodating more diffused carbon. UCX©, however, has the highest nickel and chromium levels. The alloys were exposed to a gas containing 80 vol% CO+20 vol% H2 at 650, 750, and 850ºC for 100, 500, and 1000h. Analyses including visual inspection, XRD, and SEM/EDX revealed that the alloys suffered localised attacks at the three temperatures but to varying degrees and in different shapes. In general, the attack initiated at the matrix rather than the primary carbides and also progressed through the matrix. Increasing the exposure temperature caused less carbon deposition and more oxides formation on the alloy surfaces leading to a reduction in the attack aggressiveness. UCX© exhibited the highest resistance to metal dusting whilst HP suffered the severest attack. The presence of high concentrations of chromium at the surface catalysed a quick formation of Cr2O3 scale that reduced the extent of metal dusting. Also, the increase in nickel content might have slowed down the carbon diffusion into the alloy. In addition, the presence of other oxide and carbide-forming elements such as silicon and tungsten might well have enhanced the alloy performance. Diffused carbon binds with free tungsten, niobium, and chromium to form carbides prolonging the incubation period prior to the attack initiation.
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Chlipala, M. Linda Guarnaccia Charles Anthony. "Longitudinal study of loneliness and depression as predictors of health in mid- to later life." [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-6124.
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Fitzwater, Kendra K. "Assessment of environmental and public health hazards of electronic waste." Virtual Press, 2007. http://liblink.bsu.edu/uhtbin/catkey/1380100.
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Electronic waste or `e-waste' is a rapidly growing form of solid waste worldwide. The heavy metals present in various electronic components demand attention because such metals may leach and pose significant health and environmental hazards (U.S. EPA, 2007). Knowledge of the potential of heavy metal leaching from e-waste represents an important contribution for developing U.S. standards for classifying e-waste as hazardous waste. Hazardous elements which leach from a variety of electronics wastes were assessed in laboratory batch studies. Electronic components evaluated included PC cathode ray tubes, PC motherboards, PC mice, television remote controls, and cellular phones. Each component was disassembled and digested using the Toxicity Characteristic Leaching Procedure (TCLP), EPA Method 1312, Method EA NEN 7371 (Dutch Environmental Agency), and Method DEV-S4 (Germany). The extracts were analyzed for lead, cadmium, chromium, silver, and cobalt. The TCLP consistently leached the greatest amounts of all metals; TCLP-soluble lead was extracted well beyond federal limits for several electronic devices.Department of Natural Resources and Environmental Management
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Schoof, Aguirre Jesús Iván. "Centro de Psicoterapia Psicoanalítica." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626372.
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El proyecto parte en base a la necesidad de salud mental en Lima, por lo que se busca (de mano del estado y el MINSA) dar servicios de salud mental junto con los servicios de aprendizaje e investigación en este campo para ayudar a así aumentar la oferta de este servicio en los sectores que más se requiere.
Además, se buscó un énfasis a partir del análisis de los edificios previamente construidos y con resultados positivos en la experiencia del usuario, así se definió como un punto importante en entorno natural como un factor que ayuda a la predisposición positiva en la terapia psicológica. Con los factores de necesidad y énfasis se buscó una ubicación que atendiera de mejor manera esos dos puntos, dando como resultado en INS ubicado en Chorrillos; zona con alto índice de problemas de salud mental y perteneciente al MINSA. El INS es un campus con actividades de servicio e investigación de la salud y que da la posibilidad de explotar la gran cantidad de áreas verdes que ahí se encuentran.
En conclusión, se busca ayudar a definir la tipología de edificios de salud mental al mismo tiempo que brindar un proyecto para saciar la demanda de una ciudad con poco cuidado en este campo.The project is based on the need for mental health in Lima, so it is sought (from the state and MINSA) to provide mental health services along with learning and research services in this field to help increase the offer this service in the sectors that are most required. In addition, an emphasis was sought from the analysis of previously constructed buildings and with positive results in the user's experience, so it was defined as an important point in the natural environment as a factor that helps the positive predisposition in psychological therapy. With the factors of need and emphasis, a location was sought that best served those two points, resulting in INS located in Chorrillos; zone with high index of mental health problems and belonging to the MINSA. The INS is a campus with health service and research activities and that gives the possibility of exploiting the large number of green areas that are there. In conclusion, it seeks to help define the type of mental health buildings at the same time as providing a project to satisfy the demand of a city with little care in this field.
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Matys, Paul. "Fluid flow and heat transfer in continuous casting processes." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28504.
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A three-dimensional finite difference code was developed to simulate fluid flow and heat transfer phenomena in continuous casting processes.
The mathematical model describes steady state transport phenomena in a three dimensional solution domain that involves: turbulent fluid flow, natural and forced convection, conduction, release of latent heat at the solidus surface, and tracing of unknown location of liquid/solid interface.
The governing differential equations are discretized using a finite volume method and a hybrid central, upwind differencing scheme. A fully three-dimensional ADI-like iterative procedure is used to solve the discretized algebraic equations for each dependent variable. The whole system of interlinked equations is solved by the SIMPLE algorithm.
The developed computer code was used for parametric studies of continuous casting of aluminum. The results were compared against available experimental data. This numerical simulation enhances understanding of the fluid flow and heat transfer phenomena in continuous casting processes and can be used as a tool to optimize technologies for continuous casting of metals.Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate
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Tripp, David William. "The thermal regime during electron beam hearth remelting." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26748.
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Electron beam hearth remelting is extensively used in refining of superalloys, titanium alloys and the recycling of these materials. The removal of impurities and exhogenous particles during the hearth melting operation depends primarily on the time at temperature relationship developed within a pool of molten metal. In the past hearth melters have acted largely on empirical evidence to specify such parameters as melt rates, power levels and skull sizes. This work describes a mathematical model which could be used to predict certain parameters (such as pool volume or alloy element evaporation rates) when given skull geometry, power input and melt rate.
A three dimensional steady state heat transfer model of both the skull and water cooled copper mould during electron beam hearth remelting has been developed. The model has been used to investigate the effects of surface temperature, liquid motion, power input, skull geometry, presence of the hearth mould and melt rate on parameters such as pool volume during skull melting.
In general the choice of any combination of operating parameters depends on a balance between the refining capacity of the process (i.e. liquid volume) and the loss of alloy elements by evaporation. In the case of melting pure materials (e.g. CP titanium) the balance is between refining capacity and efficient energy use.
It was found that forced convection is significantly more effective in increasing the volume of the liquid pool than any other single parameter. Increasing the power input to the skull, increasing the skull width and removing the water cooled copper mould from around the skull also increase the pool volume. The evaporation rates of alloy elements within the skull were most effected by changes in the power distribution and the degree of liquid motion.Applied Science, Faculty of
Materials Engineering, Department of
Graduate
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Bereolos, Nicole Margaret Franks Susan F. "The role of acculturation in the health belief model for Mexican-Americans with type II diabetes." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-4001.
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Sundaramurthy, Surya Narayanan. "New Sensing Techniques for Structural Health Monitoring of Hydraulic Hose, Composite Panels, and Biodegradable Metal Implants." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1307105130.
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Diao, Nancy. "Prenatal Metals Exposure and Child Birth and Growth in Bangladesh." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:16121151.
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The objective of this dissertation is to contribute to ongoing research on prenatal metals exposure, in terms of arsenic, lead, and manganese, and infant health and growth, and to deepen the understanding of the complexity of such problems. We seek to do so in three parts. First we examine the association between combined prenatal metals exposure and infant birth weight and head circumference. Then, we look at the effect on birth weight from the HFE gene variants and its interaction effects with arsenic. Finally, we look at the association of prenatal metals exposure and child growth up to 36 months. The study populations of all three of our studies are taken from mothers enrolled in 2 hospitals affiliated with Dhaka Community Hospital in Bangladesh. They were given self-administered questionnaires at time of enrollment and are followed after birth. Child measurements were taken at time of birth, and the biomarker for these studies are cord blood metal measurements.
In the first part of this dissertation, through multivariate linear regression, including a metal interaction term, we found that prenatal arsenic and manganese exposure individually associated with lowered birth weight and birth head circumference. We also found evidence of interactions between the two metals, suggesting that joint exposure creates greater deficit in birth outcomes. In the next part, looking at gene-environment interactions, we found significant modification effects of multiple SNPs on the HFE gene that increased the association between arsenic and birth weight. We also found direct effect of less studied HFE genes to lower birth weight. Finally, we assessed the effect of prenatal metals exposure on early growth in children through longitudinal analysis. In following the weight and height of the child from birth up to 36 months of age, our results indicated adverse association between arsenic and manganese on growth.Environmental Health
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Huston, Robert Edward. "Mixed metal/metalloid interactions affecting bioavailability : with particular reference to mine tailing risk assessment /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18757.pdf.
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Silva, Moacir Ferreira da. "Emissão de metais por veículos automotores e seus efeitos à saúde pública." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/6/6134/tde-08112007-152445/.
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Introdução. A presença de partículas metálicas finas na atmosfera urbana é preocupante considerando que um significativo acúmulo desses elementos no ar ambiente tem sido registrado nas últimas décadas. As informações sobre os teores de metais nas emissões de escapamentos dos veículos automotores são bastante limitadas, não sendo encontradas referências nacionais específicas sobre o tema. Objetivo: Caracterizar experimentalmente as frações fina e grossa de partículas (PM10), e os metais que compõem essas partículas emitidas na exaustão dos veículos dos ciclos Otto e Diesel.Método: Foram ensaiados dois veículos do ciclo Otto em um dinamômetro de chassi, seguindo ciclo de condução e sistema de amostragem padronizado pela norma NBR 6601 (2005): e dois veículos do ciclo Diesel, em ensaio de aceleração livre segundo a norma NBR 13037 (2001) e em operação em marcha lenta. As partículas com diâmetro ≤10 foram selecionadas e as frações fina e grossa obtidas por impactação em filtros de policarbonato, sendo sua composição elementar (elementos com Z >10) obtida pela técnica analítica de espectroscopia de raio-X (PIXE). Resultados: Os veículos a µm diesel apresentaram uma emissão média de partículas (PM10) coletada no fluxo sem diluição de aproximadamente 20,166 mg/m3, os veículos a gasolina de 0,411 gm/m3 e a álcool de 0,142 gm/m3 coletadas no fluxo de diluição. Os principais metais identificados na exaustão foram Al, Si, K, Ca, Mn, Fé, Ni, Cu, Zn, Pt e Pb, com algumas variações em função do tipo de combustível e veículo ensaiado. A média das concentrações total de PM10 presente na exaustão dos veículos ensaiados. Conclusão. Os veículos a diesel são os maiores emissores de material particulado, seguidos pelos veículos a gasolina e álcool, respectivamente. A avaliação das partículas amostradas alerta para o fato de que nos três tipos de veículos a maior parte das emissões é pertencente à fração fina. Considerando que os metais identificados podem fixar-se às partículas finas e penetrar no organismo humano e que alguns compostos metálicos, além de apresentarem efeitos carcinogênicos, são também potentes alergogênicos e sensibilizantes, deve ser ressaltada a necessidade de controle destas emissões para veículos em uso no Brasil de modo evitar danos à saúde.Introduction: The presence of fine metal particles in the urban atmosphere is a big concern considering that a significant accumulation of these elements has been registered during the last decades. Information about metal level in the tailpipe is scarce and specific Brazilian emission references are basically inexistent. Objective. Experimentally characterize fine and coarse PM10 particles and their metal constituents in the combustion exhaust of Otto and Diesel vehicles. Methods. Two Otto vehicles were essayed on a chassis dynamometer following a standard driving cycle using a sampling system in accordance with the NBR 6601 (2005); and two Diesel vehicles were essayed both in free acceleration tests according to the NBR 13037 (2001) standard and at idle rpm. The particles with diameter ≤10 µm were separated in the fine and coarse fraction by impaction in polycarbonate filters, and their elementary composition were determined by X-ray spectrometry (PIXE). Results. The diesel vehicles presented a PM10 particle average emission of 0,207 g/m3, whereas the gasoline vehicle presented 0,411 gm/m3 and the ethanol vehicle presented an average emission of 0,142 gm/m3 . The main metals identified in the emission were Al, Si, K, Ca, Mn, Fé, Ni, Cu, Zn, Pt and Pb, with some variations in function of both the type of fuel and vehicle essayed. The average concentration of the fine fraction corresponded to more than 60% of the total concentration of PM10 in the vehicle exhaust. Conclusion. The diesel vehicles are the highest particulate emitters, followed by the gasoline vehicles and ethanol vehicles in this order. The evaluation of the sampled particles alerts for the fact that for all the three types of vehicles the major part of the particle emitted is in the fine fraction of particle size range. Considering, that the metals identified by the analyses can penetrate in the human organism by adhering to fine particles. It is a fact that some metallic compounds in addition to presenting carcinogenic effects are also powerful allergen and sensitizer, it should be emphasized the need of in use vehicle emission control as a means of voiding harms to the population health.
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Alageel, Omar. "Bonding between metals and polymers for dental devices." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123299.
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Many dental devices combine acrylic (i.e. poly-methyl methacrylate or bisphenol A-glycidyl methacrylate) and metallic parts (i.e. titanium or stainless steel) that are bonded together. These devices often present catastrophic mechanical failures due to weak bonding between their acrylic and metallic components. These devices include dental prostheses, combining metallic frameworks (i.e. titanium) and wrought wires with acrylic resin; and orthodontic appliances, combining acrylic resin with stainless steel wrought wires or composite with stainless steel brackets. The bonding between metals and polymers in dental devices is usually performed by the mechanical interlocking, but its bond strength is still too low for dental applications. The bond strength between them would be high if the chemical bonding, which does not occur spontaneously, uses in addition to the mechanical interlock. The objective of this study was to develop a new method of creating a strong chemical bond between alloys and polymers for dental devices based on diazonium chemistry.The chemical bond between metals (i.e. titanium or stainless steel) and polymers (i.e. poly-methyl methacrylate, PMMA or Bisphenol A-glycidyl methacrylate, Bis-GMA) was achieved in two steps. In the first reaction step (primer), the aryldiazonium salts were chemically reduced to form aryl radicals which spontaneously got grafted onto the metallic surfaces. The second step of the reaction (adhesive) was optimized to achieve covalent binding between the grafted layer and PMMA or Bis-GMA. The chemical composition of the treated surfaces was analyzed with X-ray photoelectron spectroscopy (XPS), and the bonding strengths between alloys and PMMA or Bis-GMA were measured. XPS characterization and contact angle measurement confirmed the presence of a polymer coat on the treated metallic surfaces. Whereas, the mechanical test results showed a significant increase of the tensile bond strength between PMMA and treated titanium or stainless steel wire by 5.2 and 2.5 folds, respectively, compared to the untreated control group (P<0.05). Moreover, the bonding strength between metallic brackets and Bis-GMA composite was increased after the treatment depending on the bracket design by 2 to 3.9 folds compared to untreated brackets. Diazonium chemistry provides an effective way of achieving a strong chemical bond between alloys and PMMA or Bis-GMA. The resulting bonding method can be utilized to further improve the properties of dental devices, reduce debonding of dental prostheses and brackets, provide more leverage in orthodontic cases with complex mechanics, and allow the use of brackets with smaller bases.De nombreux appareils dentaires sont composés d'acrylique (c'est à dire d'un poly -méthacrylate de méthyle ou de bisphénol A- glycidyle méthacrylate) et de parties métalliques (par exemple en titane ou en acier inoxydable) qui sont collés ensemble. Ces dispositifs présentent souvent des défaillances mécaniques catastrophiques en raison de la faiblesse de la liaison entre les composantes en acrylique et celles en métal. Ces dispositifs comprennent les prothèses dentaires, alliant des cadres métalliques (c'est à dire de titane) et fils forgé avec de la résine acrylique, et les appareils orthodontiques, combinant de la résine acrylique avec des fils forgé en acier inoxydable ou un composite avec des supports en acier inoxydable. La force de liaison entre eux serait élevée si la liaison chimique, ce qui ne se produit pas spontanément, est utiliser en plus du verrouillage mécanique. Dans la première étape de la réaction, les sels d'aryl diazonium sont réduits chimiquement pour former des radicaux aryles qui sont spontanément greffés sur les surfaces métalliques La deuxième étape de la réaction a été optimisée pour réaliser la liaison entre la couche greffée et le PMMA ou le Bis-GMA. La caractérisation XPS et la mesure de l'angle de contact a confirmé la présence d'une couche de polymère sur les surfaces métalliques traitées. Les résultats des essais mécaniques ont montré une augmentation significative de la force d'adhérence à la traction entre le PMMA et le titane traité ou d'un fil en acier inoxydable de 5,2 et 2,5 plis, respectivement, par rapport au groupe témoin non traité (p < 0,05). La chimie de diazonium fournit un moyen efficace d'atteindre une liaison chimique forte entre les alliages et le PMMA ou le Bis-GMA. Le procédé de collage qui en résulte peut être utilisé pour améliorer les propriétés des appareils dentaires, réduire le décollement de prothèses dentaires et des supports, et permettre l'utilisation de supports avec des bases plus petites.
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Colley, Kay Lynne Newsom Ron. "Latino success stories in higher education a qualitative study of recent graduates from a health science center /." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3687.
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Vincent, Lynette Susanne. "The effects of amplification and selected vocal exercises on the perceived vocal health of elementary music educators." Thesis, connect to online resource, 2008. http://digital.library.unt.edu/permalink/meta-dc-6041.
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Guadagnin, Anne Rosi. "Estimativa da produção de calor e de metano entérico através da termografia infravermelha – Potencial de uso em vacas Holandês e Girolando F1." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/180104.
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O desenvolvimento de tecnologias alternativas para facilitar a mensuração da produção de calor e de metano em animais é necessário e deve trazer efeitos positivos para a indústria de produção animal. O objetivo do presente trabalho foi correlacionar a temperatura em pontos anatômicos mensurados através de termografia infravermelha com a produção de calor e a emissão de metano em vacas Holandês e mestiças Holandês x Gir. Seis vacas mestiças Holandês e Gir e quatro vacas Holandês no período médio da lactação, primíparas, foram avaliadas quanto à produção de calor e à emissão de metano diárias, por calorimetria indireta, em câmaras respirométricas. A termografia foi feita nas regiões do ânus, da vulva, da costela (no lado direito), do flanco direito, do flanco esquerdo, da pata dianteira direita, do lábio superior, do masseter e do olho. As imagens termográficas foram tomadas nesses nove pontos anatômicos anteriormente citados, a cada hora, por oito horas após a alimentação da manhã, durante cinco dias. Durante todo o experimento, as vacas receberam a mesma dieta ad libitum e a produção de leite e o consumo foram registrados diariamente O estudo compreendeu 40 dias, incluindo os dias de adaptação dos animais às câmaras respirométricas. A produção diária de metano foi associada com a termografia infravermelha do olho na hora 6 após a alimentação em vacas mestiças Holandês x Gir (r=0,85, p<0,05) e com a termografia infravermelha do olho feita na hora 5 em vacas Holandês (r=0,88, p<0,05). Além disso, a produção de calor foi correlacionada com a termografia infravermelha da pata dianteira direita uma hora após a alimentação em vacas Girolando F1 (r=0.85, p<0.05) e com a termografia infravermelha do olho cinco horas após a alimentação em vacas Holandês (r=0,90, p<0,05). Esses resultados foram posteriormente confirmados usando análise de regressão. As correlações das imagens termográficas com a produção de calor e emissão de metano foram similares entre as vacas Holandês e as vacas Girolando F1. A termografia infravermelha é efetiva na avaliação da produção de calor e da emissão de metano de vacas em lactação Holandês e Girolando F1, embora realizadas em pontos anatômicos diferentes.The development of alternative technologies that more easily assess heat and methane production of livestock animals are needed and would have positive effects on the livestock industry. The aim of this study was to correlate skin temperature assessed through infrared thermography with heat and methane production in lactating Holstein and Holstein x Gir crossbreed cows. Six Holstein and Gir crossbred and four Holstein cows, all primiparous, at midlactation were used to evaluate daily heat production and methane emissions through indirect calorimetry in respiratory chambers. Thermographic images were taken at nine different body locations every hour during eight hours after feeding for five days. Thermographic images were taken at the following regions: anus, vulva, ribs (on the right side), left flank, right flank, right front foot, upper lip, masseter and eye. During the whole trial cows received the same diet ad libitum, milk yield and feed intake were daily recorded. Data collection lasted 40 days, including adaptation of the animals to the respiratory chambers Daily methane emission was correlated with infrared thermography taken at the eye six hours after feeding in Holstein x Gir crossbred cows (r=0.85, p<0.05) and with infrared thermography taken at the eye five hours after feeding in Holstein cows (r=0.88, p<0.05). Also, heat production was correlated with infrared thermography taken at the right front foot one hour after feeding in Holstein x Gir crossbred cows (r=0.85, p<0.05) and with infrared thermography taken at the eye five hours after feeding in Holstein cows (r=0.90, p<0.05). These results were further confirmed using regression analysis. Correlations between infrared thermography and heat production or methane emissions are similar for Holstein and Holstein x Gir crossbred. Infrared thermography is effective in assess heat production and methane emission in Holstein and Holstein x Gir crossbred lactation cows albeit taken in different anatomical points.
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Kim, Jeong Ah. "The role of legislation in driving good occupational health and safety management systems: A comparison of prescriptive based legislation." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15966/.
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Countries seek to control exposure to hazardous substances and environments by the enactment of legislation. In the past thirty years, two major different approaches to occupational health and safety legislation have been devleoped by countries around the world. The performance-based legislative approach has been linked with the emergence of occupational health and safety management systems but no research has previously been done to determine whether or not the legislative approach taken by government influences the introduction or form of occupational health and safety management systems used by organisations. Similarly, although the reasons why Australia and other countries have moved to performance-based legislation have been explained in terms of social, political and economic factors that influenced the change, little research has been done on the effectiveness of this approach compared with the prescriptive approach of countries such as Korea. -I- The overall aim of this research is to develop a conprehensive understanding of the management of expusre to heavy metals in selected industries in Korea and Australia. The specific objectives of the study are to determine: The effectiveness of heavy metal exposure management in the fluorescent lamp manufacturing industry in Korea, and an Oral Health Service, and lead-risk workplaces in Queensland, Australia; The management of the legislative arrangements for health surveillance in Korea and Queensland, Australia; The characteristics of the occupational health and safety management systems that are in use in the heavy metal industries in Korea in Australia; and The effectiveness of prescriptive and performance based legislative systems in protecting the health and safety of workers in heavy metal based industries. Secondary analysis of biological monitoring data from 6 fluorescent lamp manufacturing companies (8 workplaces) in Korea was used to examine the extent of mercury exposure and the effectiveness of the health surveillance system in that country. A survey of dental workers in an oral health service in Queensland provided data on the extent of mercury exposure to the workforce and workers' attitudes to the management of occupational risks. The efficiency of the lead health surveillance in Queensland was examined by way of a questionnaire survey of lead designated doctors in the state. A survey of registered lead-risk companies and the oral health servies in Queensland, and 5 of the fluorescent lamp manufacturing companies in Korea provided data on the occupational health and safety management systems in place in these organisations. The health surveillance system for mercury exposed workers in Korea was found to have reduced the incidence of workers with biological levels of mercury above the Baseline Level from 14% in 1994 to 7% in 1999. Bilogical testing of dental workers in Queensland discovered no workers with biological levels of mercury approaching the Baseline Level and air monitoring failed to locate any areas where workers were likely to be exposed to levels approaching the Workplace Exposure Standard. The staff of the Oral Health Service were generally aware of the occupational health and safety management systems in place but only 43% felt that mercury management in the workplace effectively prevented exposure. The lead surveillance system in Queensland was found to be inadequately managed with approximately 37% of registered doctors no longer practicing in the field and their being no way for the government to collect reliable data on the extent of lead exposure in workplaces. The occupational health and safety management systems in the companies surveyed in Queensland and Korea were found to be influenced by the legislative arrangements in place in each of the locations. The Korean systems were more geared to meeting the regulatory requirements whereas the Queensland systems were geared more towards a risk management approach. However substantial differences were also noted depending on the size of the organisation in each case. Legislative arrangements in Korea and Queensland were found to provide reasonable protection from heavy metal exposure to workers however improvements in both systems are needed. The legislation was also found to influence the occupational health and safety management systems in place with performance-based legislation producing systems having a wide risk management focus while a narrower regulatory based focus was noted in Korea where more prescriptive legislation is in force. A confounding factor in the nature of the occupational health and safety management system in place is the size of the organisation and particular attention needs to be paid to this when legislative approaches are considered.
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Kuper, Michael W. "Investigations Near the Fusion Boundary of Grade 91 Steel Dissimilar Metal Welds with Nickel Based Filler Metals." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1543505600533312.
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