The EPA Lead and Copper Rule set action limits for lead and copper concentrations in drinking water, but accelerated corrosion of lead in distribution systems due to a galvanic connection to copper. Prior research has demonstrated that the effects of galvanic corrosion can be controlled by water chemistry. This study not only investigated the main effects of alkalinity, natural organic matter (NOM), nitrate, disinfectant and inhibitor to galvanic corrosion, but also the interplay between these factors. A 2-level factorial (2v5-1) design was adopted which resulted in 16 testing conditions. Results of bench-scale experiments using static pipes with lead and copper segments demonstrated that alkalinity, disinfectant, inhibitor and alkalinity-inhibitor interaction had a significant impact on galvanic current. The significant factors affecting total lead release were alkalinity, NOM, disinfectant, alkalinity-inhibitor interaction, NOM-nitrate interaction, NOM-disinfectant interaction, NOM-inhibitor interaction, nitrate-disinfectant interaction and disinfectant-inhibitor interaction.

The EPA Lead and Copper Rule set action limits for lead and copper concentrations in drinking water, but accelerated corrosion of lead in distribution systems due to a galvanic connection to copper. Prior research has demonstrated that the effects of galvanic corrosion can be controlled by water chemistry. This study not only investigated the main effects of alkalinity, natural organic matter (NOM), nitrate, disinfectant and inhibitor to galvanic corrosion, but also the interplay between these factors. A 2-level factorial (2v5-1) design was adopted which resulted in 16 testing conditions. Results of bench-scale experiments using static pipes with lead and copper segments demonstrated that alkalinity, disinfectant, inhibitor and alkalinity-inhibitor interaction had a significant impact on galvanic current. The significant factors affecting total lead release were alkalinity, NOM, disinfectant, alkalinity-inhibitor interaction, NOM-nitrate interaction, NOM-disinfectant interaction, NOM-inhibitor interaction, nitrate-disinfectant interaction and disinfectant-inhibitor interaction.

lack of consensus among the world researchers on the significance of Po-210 build up in lead cooled reactors. The second objective is to evaluate the advantages and disadvantages of selected candidate metal coolants. In addressing both objectives, the computer code ORIGEN was used. To establish the background basis for these assessments, fundamental concepts of reactor physics are reviewed and discussed.

In todayâ s Flip Chip (FC) and Ball Grid Array (BGA) electronic packages solder joints provide both the electrical as well as the mechanical connections between the silicon chip and the substrate. Due to coefficient of thermal expansion (CTE) differences between the chip and substrate the solder joints undergo thermomechanical stresses and strains as an electronic package is heated and cooled with power on/off cycles. Advances in chip designs result in chips that are larger, run hotter and demand improved resistance to creep and low-cycle fatigue in the solder joints. In this study the strengthening of these joints with two different reinforcements is explored: a hard particulate and a shape memory alloy (SMA) single fiber composite (SFC). A baseline is established with a SnAgCu solder that is then compared to test runs on the same solder matrix with Copper particles and then the SMA, Nickel- Titanium wire as reinforcements.

A dissertation submitted in partial compliance with the requirements for the Master's Diploma in Technology: Homoeopathy, TechniKon Natal, Durban, 1994. / This study contains a review of the major recognizable Industrial problem of chronic lead toxicity. Lead poisoning has been recognized for thousands of years, dating beclt to the Roman Empire. Today, Industries In South Africa and worldwide struggle to maintain low blood lead levels In their employees and companies have to abide by regulations to ensure they ere doing all that Is In their power. Cooltson Chemicals (Pty) Limited, In Durban, which has a factory which produces lead based chemicals, was approached with regard to treating the workers exposed to the lead dust and fumes with Homoeopathlc Slmlllimum. This Individualistic Homoeopathlc treatment depends on the person's symptoms and signs on a physical, mental and emotional level, and by treating the person as a whole, the excretion of toxic lead occurs. Thus lower lead levels result. According to Herneeepetntc methodology, It Is the sum of all the symptoms and signs In each Individual ease of a disease that Is the main pointer In the choice of the remedy. This Is where despite many complaining of a slmillar condition, or suffering from a common complaint, different Homoeopathlc remedies may be prescribed. Lower blood lead levels result In fewer retrenchments as once a factory employee continually presents with excessively high blood lead levels, he risks losing his Job. A sample group of twenty volunteers was obtained from this factory and each werker tooit his prescribed medication and had blood and urine tests talten at regular Intervals over five months. The precise methodology and the consequent results are explained In this paper. The results were analysed using the computer program, SGPLUS,to obtain summary statistics. The blood lead results were subjected to The Wilcoxon Signed RankTest to determine the 11kreasesand decreases In the levels over the monitoring period. Due to sample size and the presence to only one group In the research, the remaining results were from visual observation. Based on the problems encountered during this study, recommendations are made If further research Is to be done along similar guidelines. A final conclusion closes the study. The urine porphyrin tests are not a true Indicator of lead metabolism or excretion and these results are therefore not valid. A slight change did occur In the blood lead levels as Is discussed. A great deal of progress remains to be made with the aim of lowering blood lead levels In lead-exposed factory workers. Homoeopathy has the potential to alleviate this serious problem of chronic lead toxicity. Further research could provide Industry with the answer. Presently the emphasis Is on prevention of excessively high blood lead levels with only removal from exposure as the last possible means of alleviating the problem. If a method to solving lead toxicity In the Industrial sphere can be found, It has numerous possibilities In nonIndustry. Thus an opening exists for Homoeopathy. / M

This thesis is about brass alloys with low lead levels for manufacturing of turned components destined for human consumption. Is it technically possible, economically viable and environmentally necessary to produce lead-free brass alloys? Turning tests and leaching tests has been carried out in low-lead brass. The result of the tests carried out show that it is technically possible to produce faucets in low-leaded brass, but since these alloys are harder and less ductile, it takes more power and more cooling when it is processed. There should be more reality-based tests in regular machines that belong in the line of manufacturing. Tests is needed to find out which tool materials, cutting angles, cooling, etc. which are needed to manufacture products with the right surface, dimensions, durability, etc. One thing that no one knows today is the lifetime of a faucet made of low-lead brass. If these faucet’s do not have a higher life than that made in CW 602 N, it is a major strain on nature to produce these in low-lead brass, then to maintain production of the faucets as it is today. No information has come from the Boverket of tougher requirements for lead content in brass. This makes it difficult to know how much effort that is needed to replace lead. A legal requirement or to lose market areas is otherwise a good motivation to move forward. / <p>http://www.du.se/md:Materialdesign är en civilingenjörsutbildning som ges i samarbete mellan Högskolan Dalarna (HDa) i Borlänge och Kungliga Tekniska Högskolan (KTH) i Stockholm. Det är KTH som utfärdar examensbeviset, även för dig som studerar i Borlänge.</p>

1 Tree rings and peat bogs as archives of recent trends in Pb and Hg deposition in the Czech Republic Milan Zuna, 2012 Abstract The environment polluted by toxic metals is currently one of the most topical subjects studied in a great many countries. Toxic metals and their forms are studied primarily because of their negative impact on the environment and also on human health. In the territory of the Czech Republic, direct measurements of the concentrations of these substances are available only for a limited time period. Consequently, indirect methods, such as geochemical archives, are used to determine the historical environmental burdens from these metals. Historical lead concentrations (Pb) were studied on peat bog profiles and tree rings in selected localities in the Czech Republic. Altogether 12 peat bog profiles and 33 wood cores (Picea abies) were studied, in the border territories of the Czech Republic with different historical burdens (Krušné Hory - Novodomské rašeliniště - ND, Jizerské hory - Bílá Smědá - BS, Šumava - Jezerní slat - JS), and in a historically burdened area polluted by processing of Pb- Ag ores (Příbram-Brdy). In the vicinity of Příbram, areas around the Brdy ridge (9 km east of the Pb metallurgical works) as well as in the immediate vicinity of the metallurgical works. We used the...

Doctor of Philosophy / Department of Agronomy / DeAnn R. Presley / The abandoned lead (Pb) and zinc (Zn) mines in the Tri-State Mining District of Kansas, Missouri, and Oklahoma have left a legacy of environmental contamination. The waste materials are highly polluted, not only with Pb and Zn, but also cadmium (Cd), which often co-occurs geologically with Zn. The District includes Galena, Kansas, where mines operated between 1876 and 1970. Because limited information exists concerning these mines, three studies were done to characterize them and to investigate a way to remediate the mine waste materials. In the first study, the physical characteristics of the mine waste materials were determined. Plots at Galena that had been established by researchers in May 2006 were sampled in November 2014, 8.5 years after they had received amendments (combinations of compost, lime, and bentonite). Water content, bulk density, infiltration rate, unsaturated hydraulic conductivity, aggregate stability, and particle size distribution were determined. The physical characteristics were highly variable, and the amendments added 8.5 years earlier had no effect on them, except the wind erodible fraction (fraction <0.84 mm in diameter) which was low on treatments that contained bentonite. Because biosolids had never been applied to the mine waste materials at Galena for remediation, an experiment was done to see their effect on plant growth and availability of heavy metals. In 2014 the plots established in 2006 were sampled and a greenhouse study was set up with sudex [Sorghum bicolor (L.) Moench x S. Sudanese (P.) Staph]. Plants grew in the mine waste materials with and without biosolids, and 110-111 days after planting the roots, shoots, and heads with grain were harvested and analyzed for heavy metals. At the same time, the mine waste materials were analyzed for heavy metals, organic carbon (C), nitrogen (N), and phosphorus (P). Plants grew better with biosolids than without biosolids, and only the plants grown with biosolids produced heads . Plants grown without biosolids were stunted and showed severe heavy metal toxicity. Organic C and P were increased in the mine waste materials after the addition of biosolids. Thus, the biosolids increased organic C and P, and they apparently made the heavy metals less available for plant uptake. Many studies have shown the importance of attic dust in documenting metal pollution from a mine. Attic dust in Galena had never been studied, so in a third experiment, 14 dust samples in Galena were collected from interiors (attics and one basement) of nine different buildings using two methods: sweeping with a brush and vacuuming. Dust samples were analyzed for heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, and Zn), mineralogy using X-ray diffraction (XRD), scanning electron microscopy (SEM) in conjunction with energy dispersive spectroscopy (EDX), and particle size. Concentrations of Cu, Fe, Mn, Ni, and Zn in the dust were higher than in the mine waste materials. The results from XRD agreed with those from the SEM-EDX analysis. About 10% of each dust sample contained particulate matter (PM) with a diameter of less than 10 μm (PM₁₀), which is a health concern.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

The addition of lead to the copper alloys increase the machinability of thework material (without reference here to environmental factors) and reduces the overall production cost of the components at different stages, despite copper being expensive, which makes a challenging task to replace lead. Since lead is dangerous to human health. Many materials are considered to replace lead in brass and silicon is one of the alternative. This thesis characterizes the lead and the lead free brass's surfacemetallurgy for a certain cutting data. The study includes identification of alteredmaterial zones (AMZ) defined by the plastic deformation, hardness alterationsand grain distributions.The study results include the analysis of deformed subsurface region andcomparison exemplifying differences between the two materials under twodifferent studies. / Lead free brass