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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
761

Study on behavior of heavy metals in semi-aerobic landfill sites of municipal solid waste incinerator residues / 都市ごみ焼却残渣の準好気性埋立地における重金属類の挙動に関する研究

Xiong, Yiqun 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22427号 / 工博第4688号 / 新制||工||1732(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高岡 昌輝, 教授 酒井 伸一, 准教授 大下 和徹 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
762

Potencijal primene stabilisanog i „zelenom“ sintezom produkovanog nano gvožđa (0) za remedijaciju sedimenta kontaminiranog metalima / Potential application of stabilized and "green" produced nano zero -valent iron for remediation of sediment contaminated with metals

Slijepčević Nataša 02 October 2020 (has links)
<p>Ekolo&scaron;ki&nbsp; problem&nbsp; svetskih&nbsp; razmera&nbsp; predstavlja&nbsp; zagađenost&nbsp; sedimenta&nbsp; te&scaron;kim&nbsp; metalima, usled negativnih ekolo&scaron;kih efekata metala na životnu sredinu. Mnoge zemlje i regioni, kao i na&scaron;a zemlja&nbsp; suočavaju&nbsp; se&nbsp; sa&nbsp; ovom&nbsp; problematikom,&nbsp; koja&nbsp; je&nbsp; vrlo&nbsp; rasprostranjena&nbsp; usled&nbsp; sve&nbsp; brže urbanizacije&nbsp; i&nbsp; industrijalizacije,&nbsp; a&nbsp; sa&nbsp; sve&nbsp; većom&nbsp; nebrigom&nbsp; usled&nbsp; ispu&scaron;tanja&nbsp; otpadnih&nbsp; voda&nbsp; bez prethodnog&nbsp; preči&scaron;ćavanja&nbsp; u&nbsp; vodotokove.&nbsp; Prilikom&nbsp; promene&nbsp; uslova&nbsp; vodenog&nbsp; ekosistema,&nbsp; može doći do&nbsp; izluživanja&nbsp; metala&nbsp; i &scaron;tetnih efekata na&nbsp; životnu sredinu kao&nbsp; i&nbsp; na zdravlje&nbsp; ljudi. Stoga je remedijacija sedimenata zagađenih metalima ključna aktivnost u okviru procesa potpune sanacije vodenog ekosistema, a ekonomične, efikasne i ekolo&scaron;ki prihvatljive tehnike remedijacije su hitno potrebne&nbsp; i&nbsp; rado&nbsp; primenljive&nbsp; u&nbsp; tretmanu&nbsp; na&nbsp; velikoj&nbsp; skali.&nbsp; Pre&nbsp; primene&nbsp; remedijacione&nbsp; tehnike&nbsp; na velikoj skali, neophodna su ispitivanja pri laboratorijskim uslovima i pilot skali.&nbsp; Na kraju svakog uspe&scaron;nog&nbsp; laboratorijskog&nbsp; ispitivanja&nbsp; nalaze&nbsp; se&nbsp; pilot&nbsp; istraživanja.&nbsp; Pomoću&nbsp; njih&nbsp; se&nbsp; dobija&nbsp; p ravi odgovor u smislu izbora optimalne tehnologije imajući u vidu investicione i operativne tro&scaron;kove,<br />postignuti rezultat i krajnje ciljeve u pogledu upravljanja postrojenjem i otpadom. U ovom radu ispitan&nbsp; je&nbsp; potencijal&nbsp; primene&nbsp; stabilisanog&nbsp; i&nbsp; zelenom&nbsp; sinte zom&nbsp; produkovanog&nbsp; nano&nbsp; Fe(0)&nbsp; zaremedijaciju&nbsp; sedimenta&nbsp; zagađenog&nbsp; te&scaron;kim&nbsp; metalima.&nbsp; Kao&nbsp; remedijaciona&nbsp; tehnika&nbsp; odabrana&nbsp; je stabilizacija/solidifikacija,&nbsp; koja&nbsp; podrazumeva&nbsp; dodavanje&nbsp; agenasa&nbsp; za&nbsp; imobilizaciju&nbsp; metala&nbsp; u sedimentu&nbsp; sprečavajući&nbsp; time&nbsp; potencijalni&nbsp; rizik&nbsp;&nbsp; od&nbsp; izluživanja&nbsp; metala&nbsp; u&nbsp; životnu&nbsp; sredinu. Konvencionalni&nbsp; materijali&nbsp; poput&nbsp; letećeg&nbsp; pepela,&nbsp; cementa,&nbsp; gline&nbsp; se&nbsp; već&nbsp; odavno&nbsp; koriste&nbsp; u&nbsp; ovu svrhu. Kako u dana&scaron;nje vreme raste potražnja za novim, lako dostupnim agensima za stabilizaciju<br />sedimenta, do&scaron;lo se na ideju o primeni nanomaterijala na bazi gvožđa, tj. nano Fe(0) stabilisanog nativnom glinom&nbsp; i produkovanog redukcijom pomoću organskih&nbsp; molekula prirodno prisutnih u ekstraktu&nbsp; li&scaron;ća&nbsp; hrasta&nbsp; i&nbsp; crnog&nbsp; duda.&nbsp; Nanomaterijali&nbsp; su&nbsp; sintetisani&nbsp; i&nbsp; karakterisani&nbsp; različitim metodama&nbsp; i&nbsp; tehnikama.&nbsp; U&nbsp; nastavaku,&nbsp; u&nbsp; cilju&nbsp; efikasnosti&nbsp; njihove&nbsp; primene&nbsp; za&nbsp; stabilizaciju sedimenta, sprovedeni su ekstrakcioni i dinamički laboratorijski testovi izluživanja. Odabrane su sme&scaron;e sedimenta i nanomaterijala koje su pokazale najbolju efikasnost tr etmana. Nakon toga se ispitivanje&nbsp; nastavilo&nbsp; na&nbsp; pilot&nbsp; skali,&nbsp; gde&nbsp; se&nbsp; pratilo&nbsp; pona&scaron;anje&nbsp; nanomaterijala&nbsp; u&nbsp; zavisnosti&nbsp; od konvencionalnih&nbsp; materijala&nbsp; koji&nbsp; su&nbsp; već&nbsp; u&nbsp; literaturi&nbsp; dokumentovani&nbsp; kao&nbsp; efikasni&nbsp; imobilizacioni agensi. Dodatna potvrda uspe&scaron;nosti tretmana data je analizom i karakterizacijom s/s sme&scaron;a nakon pilot&nbsp; ispitivanja&nbsp; Na&nbsp; osnovu&nbsp; dobijenih&nbsp; rezultata&nbsp; proces&nbsp; se&nbsp; uspe&scaron;no&nbsp; pokazao&nbsp; pri&nbsp; laboratorijskim uslovima,&nbsp; a&nbsp; takođe&nbsp; i&nbsp; prilikom&nbsp; pilot&nbsp; tretmana,&nbsp; odnosno&nbsp; nakon&nbsp; pilot&nbsp; tretmana&nbsp; nije&nbsp; do&scaron;lo&nbsp; do povećanih koncentracija&nbsp; izluživanja metala iz s/s sme&scaron;a, kao ni degradacije sme&scaron;a nakon procesa ovlaživanja&nbsp; tokom&nbsp; &scaron;est&nbsp; meseci.&nbsp; Na&nbsp; osnovu&nbsp; toga,&nbsp; ovako&nbsp; tertirani&nbsp; sediment&nbsp; se&nbsp; može&nbsp; bezbedno odlagati&nbsp; na&nbsp; deponije,&nbsp; ili&nbsp; pak&nbsp; iskoristiti&nbsp; za&nbsp; &bdquo;kontrolisanu&ldquo;&nbsp; upotrebu,&nbsp; izgradnju&nbsp; puteva,kamenoloma, pomoćnih objekata i slično. Rezultati su doprineli u cilju trajnijeg re&scaron;avanja pitanja odlaganja&nbsp; zagađenog&nbsp; (izmuljenog)&nbsp; rečnog&nbsp; sedimenta,&nbsp; pri&nbsp; čemu&nbsp; se&nbsp; u&nbsp; procesu stabilizacije/solidifikacije&nbsp; dobijaju&nbsp; proizvodi&nbsp; sa&nbsp; dodatom&nbsp; vredno&scaron;ću&nbsp; neumanjenog&nbsp; kvaliteta .Nanomaterijali sintetisani u ovom radu na&nbsp; bazi ekstrakta li&scaron;ća biljaka doprinose kako očuvanju životne&nbsp; sredine,&nbsp; tako&nbsp; i&nbsp; ekonomičnosti&nbsp; primene&nbsp; remedijacione&nbsp; tehnike.&nbsp; Zahvaljujući&nbsp; velikoj specifičnoj&nbsp; povr&scaron;ini,&nbsp; malim&nbsp; dimenzijama&nbsp; čestica&nbsp; i&nbsp; velikom&nbsp; kapacitetu&nbsp; za&nbsp; imobilizaciju&nbsp; te&scaron;kih<br />metala predstavljaju efikasnu alternativu komercijalno dostupnim materijalima, &scaron;to ih čini veoma atraktivnim&nbsp; i&nbsp; obećavajućim&nbsp; u&nbsp; budućnosti&nbsp; pri&nbsp; tretmanu&nbsp; rečnog&nbsp; sedimenta&nbsp; zagađenog&nbsp; te&scaron;kim metalima.</p> / <p>The pollution of sediment by heavy metals represents a large environmental problem all<br />over the world.&nbsp; A&nbsp; lot of countries&nbsp; in the region&nbsp; as well as our country deal with this problem, which&nbsp; is&nbsp; widespread&nbsp; because&nbsp; of&nbsp; the&nbsp; fast&nbsp; urbanization&nbsp; and&nbsp; industrialization.&nbsp; There&nbsp; is&nbsp; more&nbsp; and more&nbsp; carelessness&nbsp; about&nbsp; wastewater&nbsp; discharge&nbsp; into&nbsp; water&nbsp; flows&nbsp; without&nbsp; previous&nbsp; purification. When the conditions of the aquatic ecosystem change, metal leaching and harmful effects on the environment&nbsp; and&nbsp; human&nbsp; health&nbsp; can&nbsp; occur.&nbsp; Therefore,&nbsp; remediation&nbsp; of&nbsp; metal-contaminated sediments&nbsp; is&nbsp; crucial&nbsp; activity&nbsp; in&nbsp; the&nbsp; process&nbsp; of&nbsp; the&nbsp; complete&nbsp; ecosystem&nbsp; remediation.&nbsp; Cost effective, efficient and environmentally friendly remediation techniques are urgently needed and readily applicable in large-scale treatment. Before applying remediation techniques on the largescale,&nbsp; both&nbsp; laboratory&nbsp; and&nbsp; pilot&nbsp; tests&nbsp; are&nbsp; necessary.&nbsp; There&nbsp; are&nbsp; pilot&nbsp; studies&nbsp; at&nbsp; the&nbsp; end&nbsp; of&nbsp; each successful&nbsp; laboratory&nbsp; test.&nbsp; Those&nbsp; studies&nbsp; provide&nbsp; the&nbsp; right&nbsp; answer&nbsp; in&nbsp; terms&nbsp; of&nbsp; choosing&nbsp; the optimal technology, taking into account the investment and operating costs,&nbsp;&nbsp; the achieved resultand&nbsp; the&nbsp; ultimate&nbsp; goals&nbsp; in&nbsp; terms&nbsp; of&nbsp; plant&nbsp; and&nbsp; waste&nbsp; management.&nbsp; In&nbsp; this&nbsp; study,&nbsp; the&nbsp; application<br />potential of stabilized and green&nbsp; -&nbsp; synthesized&nbsp; nano Fe(0) for the remediation of&nbsp; heavy&nbsp; metal&nbsp; -contaminated&nbsp; sediment&nbsp; was&nbsp; investigated.&nbsp; Stabilization&nbsp; /&nbsp; solidification&nbsp; technique&nbsp; was&nbsp; chosen&nbsp; as remediation technique which involves the addition of metal immobilizing agents in the sediment thus preventing the potential risk of metal leaching into the environment. Conventional materials such as fly ash, cement and clay have long been used for this purpose. Nowadays there is need for new, easily accessible agents for the sediment stabilization. Therefore it came up with the idea of&nbsp; using&nbsp; iron-based&nbsp; nanomaterials,&nbsp; ie.&nbsp; nano&nbsp; Fe(0)&nbsp; stabilized&nbsp; by&nbsp; native&nbsp; cla y&nbsp; and&nbsp; produced&nbsp; by reduction&nbsp; using&nbsp; organic&nbsp; molecules&nbsp; naturally&nbsp; present&nbsp; in&nbsp; oak&nbsp; and&nbsp; black&nbsp; mulberry&nbsp; leaf&nbsp; extract. Nanomaterials have been synthesized and characterized by different methods and techniques. In order&nbsp; to&nbsp; be&nbsp; effective&nbsp; in&nbsp; their&nbsp; application&nbsp; for&nbsp; sediment&nbsp; stabilization,&nbsp; extraction&nbsp; and&nbsp; dynamic laboratory leaching tests were performed. Mixtures of sediment and nanomaterials were selected that showed the best treatment efficiency.&nbsp; After that, the examination was continued on a pilot scale, where the behavior of nanomaterials was monitored, depending on conventional materials which&nbsp; have&nbsp; already&nbsp; been&nbsp; documented&nbsp; in&nbsp; the&nbsp; literature&nbsp; as&nbsp; effective&nbsp; immobilizing&nbsp; agents.Additional confirmation of treatment success was given by analysis and characterization of s / s mixtures&nbsp; after&nbsp; pilot&nbsp; testing.&nbsp; According&nbsp; to&nbsp; obtained&nbsp; results,&nbsp; the&nbsp; process&nbsp; was&nbsp; successfully demonstrated&nbsp; under&nbsp; laboratory&nbsp; conditions,&nbsp; and&nbsp; also&nbsp; during&nbsp; the&nbsp; pilot&nbsp; treatment.&nbsp; After&nbsp; the&nbsp; pilot treatment&nbsp; there&nbsp; were&nbsp; no&nbsp; increased&nbsp; concentrations&nbsp; of&nbsp; metal&nbsp; leaching&nbsp; from&nbsp; s/s&nbsp; mixtures,&nbsp; nor mixture degradation after the wetting process for six months. Based on that, the sediment treated in this way&nbsp; can&nbsp; be safely disposed of&nbsp; in&nbsp; landfills, or used&nbsp; for &quot;controlled&quot; use, construction of<br />roads,&nbsp; quarries,&nbsp; auxiliary&nbsp; facilities&nbsp; and&nbsp; etc.&nbsp; The&nbsp; results&nbsp; have&nbsp; contributed&nbsp; to the&nbsp; goal&nbsp; of&nbsp; a&nbsp; more permanent solution to the issue of disposal of polluted (slugged) river sediment, whereby in the process&nbsp; of&nbsp; stabilization/solidification,&nbsp; products&nbsp; with&nbsp; added&nbsp; value&nbsp; of&nbsp; undiminished&nbsp; quality&nbsp; are obtained. The nanomaterials synthesized in this paper on the basis of plant leaf extract contribute to both the preservation of the environment and the economy of remediation techniques. Thanks to their&nbsp; large specific&nbsp; surface area, small particle size and&nbsp; large ca pacity&nbsp; for&nbsp; immobilization of heavy&nbsp; metals,&nbsp; they&nbsp; represent&nbsp; an&nbsp; effective&nbsp; alternative&nbsp; to&nbsp; commercially&nbsp; available&nbsp;&nbsp; materials.&nbsp; It makes&nbsp; them&nbsp; very&nbsp; attractive&nbsp; and&nbsp; promising&nbsp; in&nbsp; the&nbsp; future&nbsp; in&nbsp; the&nbsp; treatment&nbsp; of&nbsp; river&nbsp; sediment contaminated with heavy metals.</p>
763

Effects of Heavy Metals (Cadmium, Copper, and Mercury) on Reproduction, Growth, and Survival of Brine Shrimp (Artemia salina) from the Great Salt Lake

Gebhardt, Karl A. 01 May 1976 (has links)
The purpose of this paper is to report findings concerning the effects of cadmium , copper, and mercury on the brine shrimp Artemia Salina, of the Great Salt Lake. Metal toxicity was observed in relation to acute susceptibility, growth, reproduction, and hatching of the brine shrimp. Heavy metal concentrations such as cadmium, copper, and mercury are known to be considerably higher in the Great Salt Lake than those in both freshwater and seawater. No published study has been concerned with heavy metal effects on organisms in salinities greater than seawater (35 grams per liter total dissolved solids). The experiments reported in this paper were carried out in salinities approximating the Great Salt Lake (150-320 grams per liter total dissolved solids). Results of this study indicate that cadmium, copper, and mercury toxicities to the brine shrimp may not be comparable at varying salinities. Findings of acute toxicity experiments were compared to other heavy metal studies on marine organisms. The brine shrimp was found to be very resistant to cadmium and copper poisoning and moderately resistant to mercury. Neither cadmium nor copper inhibited hatching of the brine shrimp eggs although mercury caused severe inhibition at concentrations of 0.3 milligrams per liter. Only cadmium at concentrations between 1.0 and 33 milligrams per liter significantly suppressed growth rate and reproduction. Mercury and copper were not found to affect growth and reproduction below concentrations causing acute poisoning. Mercury was found to be the most lethal to the adult brine shrimp with a range of times to 50 percent mortality from 126 to 8.5 hours at mercury concentrations of 0.01 to 100 milligrams per liter respectively. Copper caused mortalities at concentrations of 1 to 67 milligrams per liter with respective times to 50 percent mortality of 124 and 12 hours. Copper was shown to precipitate out at concentrations near 12 milligrams per liter, Cadmium was found to be the least lethal with a range of times to 50 percent mortality from 94 to 320 hours with respective cadmium concentrations of 100 and 3.3 milligrams per liter.
764

Effect of Heavy Metals Found in Flue Gas on Growth and Lipid Accumulation for Green Algae Scenedesmus obliquus

Butler, Reece 01 May 2011 (has links)
This study evaluated the effect of several heavy metals that are present in flue gases on the algae, focusing on the growth and accumulation of lipids in the algae that can be converted to biodiesel. Concentrations for the heavy metals were calculated based on literature and assumptions. Metals were tested individually first at the highest concentrations that might be present (reference concentrations). The metals and their reference concentrations were: arsenic at 1.56 mg/L, cadmium at 0.3 mg/L, chromium at 2.6 mg/L, cobalt at 0.32 mg/L, copper at 2.62 mg/L, lead at 1.09 mg/L, nickel at 5.08 mg/L, mercury at 0.2 mg/L, selenium at 0.2 mg/L, and zinc at 8.8 mg/L. At these concentrations, most of the metals had a negative effect on the growth and lipid content of the algae. All of the metals were then tested at lower concentrations. At 1/20 the reference concentrations, the metals enhanced growth as well as lipid accumulation in the algae. At higher concentrations there was a negative effect.
765

Distribution and mobilization of heavy metals at an acid mine drainage-affected region, South China

Luo, Chen January 2020 (has links)
Dabaoshan Mine Site (DMS) is the biggest polymetallic mine in South China. The Hengshi River receives acid mine drain (AMD) waste leaching from the tailings pond and run-off from the treatment plant which flows into the Wengjiang River, Beijiang River, before discharging into the Pearl River. Discharge from the mine site results in heavy metal contamination  near the mine and lower riparian areas along the river course. The present study focuses on the distribution and mobilization of As, Cd, Pb and Zn along the Hengshi River, groundwater, fluvial sediments and soil, with a special focus on As due to its high toxicity and the fact that mining is one of the main anthropogenic sources of As. Heavy metals, grain-size, XRD, %C and S analysis were done in order to determine the physicochemical characteristics of samples. The results were used for geochemical modeling (PHREEQ) and statistical (PCA) analysis to understand and predict the behavior of heavy metals. Potential ecological risk assessment was conducted by calculating contamination degree of heavy metals in soil and sediment and it’s theoretical toxical risk. Near the tailings pond, heavy metal concentration was 2-100 times higher than chinese surface water standard for agricultural use, which decreases downstream, mianly due to dilution, sorption, precipitation and co-precipitation with minerals. In groundwater, heavy metals concentration remained low. Due to the fact that most wells were abandoned or only for household use, potential risk from groundwater is low. The soils were disturbed by industrial or agricultural activities, and heavy metal concentration varied without showing any specific trend along the river. The potential ecological risk of heavy metals are ranked as: Cd&gt;As&gt;Cu&gt;Pb&gt;Zn in sediments; Cd&gt;Cu&gt;Pb&gt;As&gt;Zn in soil. As(Ⅲ) was the predominant species in surface water, and minerals identified in soil and sediment. Arsenic from most sites exceeded the Chinese soil standard for development land. Although arsenic was assumed to have a moderate ecological risk in sediments and low risk in soils, anthropogenic activities, such as land use change and untreated sewage discharge, might reduce and release arsenic into the environment, which poses potential risk to local residents.
766

Greywater reuse - An assessment of health and nutritional quality of home gardens produce in rural South Africa

Radingoana, Makgalake Pabalelo January 2021 (has links)
Philosophiae Doctor - PhD / The majority of rural communities in sub-Saharan Africa are predominantly poor and depend largely on small-scale subsistence farming. To date, various farming mechanisms (e.g. organic farming, crop rotation, agroforestry and inter-cropping) have been introduced to improve food security and to avert hunger; however, water scarcity remains a challenge. The sub-Saharan African region is currently regarded as water stressed and this has had a significant impact on rural livelihoods. Despite being considered as a water-scarce region, the demand for water for agricultural purposes continues to increase exponentially, while, on the other hand, its supply keeps on diminishing, particularly for agricultural production.
767

Hydrogely huminových kyselin - experimentální model i aplikační forma / Hydrogels of Humic Acids - Experimental Model and Application Form

Sedláček, Petr January 2009 (has links)
The thesis deals with a utilization of hydrogels made of humic acids in both basic and applied research of this valuable natural material. The attention is paid to an interaction between the humic gel and cupric ions as the model heavy metal. The main experimental part focuses on an optimation of simple laboratory diffusion methods which serve as an innovative tool for modeling pollutants’ transport in natural humic environments. Various techniques were used in order to determine a diffusion coefficient of cupric ions in humic gel; the value is closely linked with the studied interaction between solid content of the gel and the diffusing species. Consequently, the diffusivity can be used as a standard parameter for basic reactivity mapping studies concerning humic substances. The final chapter of the thesis deals with a preparation of mixed reversible hydrogels formed by a reaction between humic acids and chitosan. These materials represent a suitable colloidal form for humic acids’ industrial and agricultural applications.
768

Factors Affecting Waste Leachate Generation and Barrier Performance of Landfill Liners / 廃棄物埋立処分場における浸出水の発生特性と遮水工の性能への影響要因の解明

Tang, Qiang 24 September 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第17933号 / 地環博第112号 / 新制||地環||22(附属図書館) / 30753 / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)教授 勝見 武, 教授 高岡 昌輝, 准教授 乾 徹 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
769

Bioavailability and rhizotoxicity of trace metals to pea : development of a terrestrial biotic ligand model

Wu, Yonghong, 1969- January 2007 (has links)
No description available.
770

The influence of heavy metals on the diet changes of Neoperla (Plecoptera) in the northwest Miramichi River, New Brunswick /

MacIntosh, John, 1967- January 2002 (has links)
No description available.

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