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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.
321

Spatial and temporal distributions of heavy metals in Hong Kong seaweeds with an analysis on the effects of heavy metals on the reproduction of the green alga ulva lactuca. / CUHK electronic theses & dissertations collection

January 2005 (has links)
No periodic patterns of temporal variations in the metal levels in U. lactuca or in other seven common seaweed species from Ping Chau were observed from 1999 to 2000. Cu levels were generally negatively correlated with other metals in seaweeds. / Spore production of U. lactuca was significantly reduced by the elevation of copper and nickel levels in the seaweed samples. The reproductive frequency of U. lactuca generally increased from January and February to the maxima in March and April. Copper, nickel and nitrate levels showed significant negative correlations with these reproductive frequencies. / The metal abundance in 24 seaweeds showed the following trend: Fe > Mn, Zn > Cu, Ni, Pb, Cr > Cd. U. lactuca and Padina australis showed relatively high mean and large range values of metal levels. Principal component analysis summarized the overall metal loadings in these 24 seaweed species. The variations in Pb, Fe, Mn and Cr levels in the seaweeds varied greatly. / There were significant spatial variations of different metal levels in the extensive study of U. lactuca from various intertidal waters in Hong Kong from 1999 to 2001. In general, metal levels in U. lactuca increased from January to March or April and then dropped in the following months. No periodic patterns or temporal trends of variations of metal levels in U. lactuca were found. Different metal levels in U. lactuca were comparatively lower than those in other studies in other countries and in past studies in Hong Kong. / There were significantly differences in various metal levels in different structures of Sargassum hemiphyllum, generally decreased in the following order: receptacles > vesicles > leaves > branches. / This thesis research involves biomonitoring levels of eight metal species (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in seaweed and the effects of these metals on the reproduction of Ulva lactuca. The study started from September 1999 and ended in June 2001, covering 40 intertidal sites in Hong Kong and 24 seaweed species. Environmental data on pH, salinity and nutrient levels (ammonia, nitrite, nitrate and phosphate) in seawater from these sites were also monitored. / Wong Tai Choi Richard. / "April 2005." / Advisers: P. C. K. Cheung; P. O. Ang, Jr. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0159. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 371-401). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.
322

Removal and recovery of copper ion (Cu²⁽) from electroplating effluent by pseudomonas putida 5-X immobilized on magnetites.

January 1996 (has links)
by Sze Kwok Fung Calvin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 118-130). / Acknowledgement --- p.i / Abstract --- p.ii / Content --- p.iv / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Literature review --- p.1 / Chapter 1.1.1 --- Heavy metals in the environment --- p.1 / Chapter 1.1.2 --- Heavy metal pollution in Hong Kong --- p.2 / Chapter 1.1.3 --- Electroplating industry in Hong Kong --- p.6 / Chapter 1.1.4 --- Chemistry and toxicity of copper in the environment --- p.7 / Chapter 1.1.5 --- Methods of removal of heavy metal from industrial effluent --- p.9 / Chapter A. --- Physico-chemical methods --- p.9 / Chapter B. --- Biological methods --- p.9 / Chapter 1.1.6 --- Methods of recovery of heavy metal from metal-loaded biosorbent --- p.17 / Chapter 1.1.7 --- The physico-chemical properties of magnetites --- p.18 / Chapter 1.1.8 --- Magnetites for water and wastewater treatment --- p.19 / Chapter 1.1.9 --- Immobilized cell technology --- p.24 / Chapter 1.1.10 --- Stirrer-tank bioreactor --- p.26 / Chapter 1.2 --- Objectives of the present study --- p.28 / Chapter 2. --- Materials and Methods --- p.30 / Chapter 2.1 --- Selection of copper-resistant bacteria --- p.30 / Chapter 2.2 --- Culture media and chemicals --- p.30 / Chapter 2.3 --- Growth of the bacterial cells --- p.32 / Chapter 2.4 --- Immobilization of the bacterial cells on magnetites --- p.32 / Chapter 2.4.1 --- Effects of physical and chemical factors on the immobilization of the bacterial cells on magnetites --- p.34 / Chapter 2.4.2 --- Effects of pH on the desorption of bacterial cells from magnetites --- p.34 / Chapter 2.5 --- Copper ion uptake experiments --- p.35 / Chapter 2.6 --- Effects of physico-chemical and operational factors on the Cu2+ removal capacity of the magnetite-immobilized bacterial cells --- p.35 / Chapter 2.7 --- Transmission electron micrograph and scanning electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.36 / Chapter 2.7.1 --- Transmission electron micrograph --- p.36 / Chapter 2.7.2 --- Scanning electron micrograph --- p.37 / Chapter 2.8 --- Copper ion adsorption isotherm of the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.37 / Chapter 2.9 --- Recovery of adsorbed Cu2+ from the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.38 / Chapter 2.9.1 --- Effects of eluents on the Cu2+ removal and recovery capacity of the magnetite-immobilized cells --- p.38 / Chapter 2.9.2 --- Batch type multiple adsorption-desorption cycles of Cu2+ using ethylenediaminetetra-acetic acid (EDTA) --- p.39 / Chapter 2.10 --- Removal and recovery of Cu2+ from the electroplating effluent by a bioreactor --- p.39 / Chapter 2.10.1 --- Batch type multiple adsorption-desorption cycles using the copper solution and electroplating effluent --- p.39 / Chapter 2.10.2 --- Continuous type bioreactor to remove and recover Cu2+ from copper solution and electroplating effluent --- p.40 / Chapter 2.11 --- Statistical analysis of data --- p.43 / Chapter 3. --- Results --- p.44 / Chapter 3.1 --- Effects of physical and chemical factors on the immobilization of the bacterial cells on magnetites --- p.44 / Chapter 3.1.1 --- Effects of cells to magnetites ratio --- p.44 / Chapter 3.1.2 --- Effects of pH --- p.44 / Chapter 3.1.3 --- Effects of temperature --- p.44 / Chapter 3.2 --- Effects of pH on the desorption of bacterial cells from magnetites --- p.49 / Chapter 3.3 --- Copper ion uptake experiments --- p.49 / Chapter 3.4 --- Effects of physico-chemical and operational factors on the Cu2+ removal capacity of the magnetite-immobilized bacterial cells --- p.49 / Chapter 3.4.1 --- Effects of pH --- p.49 / Chapter 3.4.2 --- Effects of temperature --- p.53 / Chapter 3.4.3 --- Effects of retention time --- p.53 / Chapter 3.4.4 --- Effects of cations --- p.53 / Chapter 3.4.5 --- Effects of anions --- p.57 / Chapter 3.5 --- Transmission electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.62 / Chapter 3.6 --- Scanning electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.62 / Chapter 3.7 --- Copper ion adsorption isotherm of the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.68 / Chapter 3.8 --- Recovery of adsorbed Cu2+ from the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.68 / Chapter 3.8.1 --- Effects of eluents on the Cu2+ removal and recovery capacity of the magnetite-immobilized cells --- p.68 / Chapter 3.8.2 --- Batch type multiple adsorption-desorption cycles of Cu2+ using ethylenediaminetetra-acetic acid (EDTA) --- p.74 / Chapter 3.9 --- Removal and recovery of Cu2+ from the electroplating effluent by a bioreactor --- p.74 / Chapter 3.9.1 --- Batch type multiple adsorption-desorption cycles using the copper solution and electroplating effluent --- p.74 / Chapter 3.9.2 --- Continuous type bioreactor to remove and recover Cu2+ from copper solution and electroplating effluent --- p.81 / Chapter 4. --- Discussion --- p.89 / Chapter 4.1 --- Selection of copper-resistant bacteria --- p.89 / Chapter 4.2 --- Effects of physical and chemical factors on the immobilization of the bacterial cells on magnetites --- p.89 / Chapter 4.2.1 --- Effects of cells to magnetites ratio --- p.89 / Chapter 4.2.2 --- Effects of pH --- p.90 / Chapter 4.2.3 --- Effects of temperature --- p.91 / Chapter 4.2.4 --- Effects of pH on the desorption of bacterial cells from magnetites --- p.92 / Chapter 4.3 --- Copper ion uptake experiments --- p.93 / Chapter 4.4 --- Effects of physico-chemical and operational factors on the Cu2+ removal capacity of the magnetite-immobilized bacterial cells --- p.94 / Chapter 4.4.1 --- Effects of pH --- p.95 / Chapter 4.4.2 --- Effects of temperature --- p.96 / Chapter 4.4.3 --- Effects of retention time --- p.97 / Chapter 4.4.4 --- Effects of cations --- p.98 / Chapter 4.4.5 --- Effects of anions --- p.101 / Chapter 4.5 --- Transmission electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.101 / Chapter 4.6 --- Scanning electron micrograph of Pseudomonas putida 5-X loaded with Cu2+ --- p.102 / Chapter 4.7 --- Copper ion adsorption isotherm of the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.103 / Chapter 4.8 --- Recovery of adsorbed Cu2+ from the magnetite-immobilized cells of Pseudomonas putida 5-X --- p.104 / Chapter 4.8.1 --- Effects of eluents on the Cu2+ removal and recovery capacity of the magnetite-immobilized cells --- p.104 / Chapter 4.8.2 --- Batch type multiple adsorption-desorption cycles of Cu2+ using ethylenediaminetetra-acetic acid (EDTA) --- p.105 / Chapter 4.9 --- Removal and recovery of Cu2+ from the electroplating effluent by a bioreactor --- p.107 / Chapter 4.9.1 --- Batch type multiple adsorption-desorption cycles using the copper solution and electroplating effluent --- p.107 / Chapter 4.9.2 --- Continuous type bioreactor to remove and recover Cu2+ from copper solution and electroplating effluent --- p.108 / Chapter 5. --- Conclusion --- p.110 / Chapter 6. --- Summary --- p.112 / Chapter 7. --- References --- p.115
323

Evaluation of a fish health assessment index as biomonitoring tool for heavy metal contamination in the Olifants River catchment area

Watson, Raylene Mullineux 12 September 2012 (has links)
Ph.D. / The current study evaluated a bio-monitoring technique developed in the USA by Adams, Brown and Goede, 1993. This project was sponsored by the Department of Water Affairs and Forestry (DWAF), to enable testing of the Health Assessment Index (HAI) under South African conditions. Testing took place in the Olifants River system, one of the most polluted river systems . in South Africa. Initially two river points were tested using Oreochromis mossambicus (Robinson, 1996), Clarias gariepinus (Marx, 1996) and Labeo rosae (Luus-Powell, 1997). The current study re-tested the HAI at the same two sample sites, namely Mamba and Balule in the Kruger National Park, using 0. mossambicus and C. gariepinus respectively. Two additional sites were tested in the upper catchment area, namely Loskop Dam and Bronkhorstspruit Dam. The current study further enabled the comparison of HAI results collected during drought and flood conditions. Results obtained after deployment of the HAI were corroborated using chemical analysis of water, sediment and biota. Water and sediment analysis was carried out by the Institute for Water Quality Studies using standard techniques. Bio-accumulation of aluminium, copper, iron, lead, manganese, nickel, strontium and zinc was assessed in the gills, liver, skin and muscle tissue of sample fish using standard Atomic Absorption Spectrometry techniques. Modifications made to the original HAI involved the inclusion of variable ranking in the assessment of fish parasites, with endo- and ectoparasites evaluated separately. Testing of this parasite hypothesis lead to the development of a Parasite Index component to the HAI. Assessment of water, sediment and fish tissue determined that the Olifants River system is indeed exposed to macro and heavy metal pollutants, which negatively affect aquatic health. Constituents posing the greatest threat are chlorides, fluorides, phosphates, total dissolved solids, copper and iron concentrations. Testing the HAI and parasite hypothesis using C. gariepinus, provided the most meaningful results. During testing of the parasite hypothesis both endo- and ectoparasite numbers conformed to the suggested idea that higher endoparasite numbers will occur at highly impacted areas, whereby ectoparasite numbers will be low. This was particularly evident in the lower catchment area, whereby comparisons between drought and flood conditions were carried out. Subsequent decreases in water quality directly after the flood were noted using water and sediment analysis. This observation reflects the results gathered using the HAT and during testing of the parasite hypothesis at all four sample sites. During statistical analysis of the HAI, using logistic regression analysis, parasite numbers, more specifically endoparasite numbers, were the most indicative of fish health. Environmental stressors (flood conditions) result in immunological responses observed in fish, and are reflected statistically using the HAI as changes in WBC %. It is suggested that endoparasites and WBC % provide the best overall assessment of fish condition. These variables should thus not be eliminated, in order to streamline the HAI evaluation procedures. Testing of this bio-monitoring technique under South African conditions provided meaningful results. This indicates that the HAI can be used to assess water quality, with existing water monitoring programmes further benefiting from its incorporation.
324

Evaluation of phytoremediation potentials of Phytolacca dodecandra, Adhatoda schimperiana and Solanum incanum for selected heavy metals in field setting located in central Ethiopia

Alemu Shiferaw Debela 03 1900 (has links)
Pollution of soil by trace metals has become one of the biggest global environmental challenges resulting from anthropogenic activities, therefore, restoration of metal contaminated sites needs due attention. The use of phytoremediation technologies as nature-based solution to pollution, could support successful implementation of green economic development strategies; with economically affordable and environmentally friendly benefits. The present investigation employed an exploratory study on the phytoremediation potentials of three selected native plants; Phytolacca dodecandra (L’Herit), Adhatoda schimperiana (Hochst) and Solanum incanum L, dominating areas close to heavy metal contamination sources; in metropolitan centers of Addis Ababa. In this work, concentration of six heavy metals of interest chromium (Cr), lead (Pb), cadmium (Cd), nickel (Ni) copper (Cu) and zinc (Zn) were examined in soil and in different tissues (leaves, stems and roots) of selected plants (both seedlings and mature plants), in dry and rainy seasons using atomic absorption spectrophotometer. Efficiency of phytoremediation is discussed based on calculated values of Bio-concentration Factor (BCF), Translocation Factors (TF) and Bioaccumulation Coefficient (BAC). Phytolacca dodecandra showed BCF, TF and BAC > 1 for Zn, Pb, Ni, Cu and Cd Adhatoda schimperiana gave BCF, TF and BAC > 1 for Zn, Cu, Ni and Cr; likewise, BCF, BAC and TF values of > 1 were noted in Solanum incanum for Zn, Cu, Pb and Ni. Based on these scenarios, the three plants could be utilized for phytoextraction of contaminated soil. Conversely, BCF and BAC for Cr levels in tissues of Phytolacca dodecandra were all < 1, which indicates unsuitability for phytoremediation of Cr in contaminated soils. Besides, Adhatoda schimperiana retained Pb and Cd in their roots showing root BCF > 1, while BAC and TF < 1, which highlights its suitability for phytostabilization. Moreover, BCF, TF and BAC values of < 1 noted for Cr and Cd in Solanum incanum reveal that Solanum incanum may not be a good candidate for remediation of Cr and Cd contaminated environments. In conclusion, results from this study revealed that the selected plants can accumulate substantial amounts of the above trace metals in their tissues and can serve as prospective phytoremediators of most of these metals. Phytoextraction and phytostabilization were the main mechanisms of remediation in this study. / Environmental Sciences / Ph. D. (Environmental Sciences)
325

An assessment of heavy metal pollution near an old copper mine dump in Musina, South Africa

Singo, Ndinannyi Kenneth 24 October 2013 (has links)
Heavy metal pollution in water and soil is a serious concern to human health and the associated environment. Some heavy metals have bio-importance but the bio-toxic effects of many of them in human health are of great concern. Hence, there was a need for proper understanding of the concentration levels of these heavy metals in ground water and soil around the community residing in the vicinity of the defunct mine. Mining has become prominent in this area because of the existence of copper lodes, veins and veinlets. It was therefore necessary to assess these selected metals associated with copper mining as their concentration has a tendency to affect the environment and human health. The objective of this study was to establish the levels of lead (Pb)-zinc (Zn)-copper (Cu)-arsenic (As)-nickel (Ni) metals in ground water and soil associated with an old copper mine in the vicinity of the township and to compare them with the South African and international standards in order to safeguard the health of the community using such water for drinking purpose. Clean sampling plastic bottles were used to collect water from five water boreholes being used at present. Water samples were filtered using membrane filtration set LCW (0.45 μm). The samples were digested sequentially with different procedures for the total metal concentration. Concentrations of four metals commonly associated with Cu mining were examined at five different water boreholes which are used for drinking and industrial purposes. Flame Atomic Absorption Spectrophotometer (Perkin Elmar S/n 000003F6067A, Singapore) was used to analyze metals in water samples at Eskom Ga-Nala Laboratory: pH, electrical conductivity and turbidity were analyzed using an auto titrator meter (AT- 500,Japan), conductivity meter (Cole-parmer® YO-19601-00) and turbidity meter (AL 250TIR, Agua lytic, German) respectively. Soil samples were collected from the selected areas where human health is of a serious concern, and a hand held auger drill was used to recover samples, while shovels were used to prepare the sampling area. The samples were sieved up to 63.0 μm particle size and digested with aqua-regia. Flame Atomic Absorption Spectrophotometer (Model: AA400; Year: 2008; Manufacturer: Perkin Elmer; Germany; Serial no: 201S6101210) was used at the University of Venda Laboratory to analyze soil from the study area for possible heavy metal contamination due to the defunct Cu mine in the area. v The results showed variation of the investigated parameters in water samples as follows: pH, 6.0 to 7.51; EC, 70.0 to 96.40 μS/cm and turbidity, 1.05 to 4.56 NTU. The mean concentration of the metals increased in the followed order: Pb<Cu<As<Ni. Ni is the most abundant in the ground water determined with value of (6.49 μg/g). The observations have confirmed that most ground water contains an appreciable quantity of Ni. The mean value of As in water is (4.20 to 4.84 μg/g), Pb and Cu have (2.13 to 2.58 μg/g) and (1.52 to 2.52 μg/g) respectively. For soil samples, the mean concentration of the metals increased in the following order: Pb<Cu<Zn<As<Ni. Pb ranged from (0.023 to 0.036 μg/g) followed by Cu (0.28 to 0.45 μg/g) then Zn (0.026 to 0.053 μg/g), the mean range of As in soil ranged from (0.054 to 0.086 μg/g). However, some studies show much higher contamination of As from the natural sources and Ni with (0.057 to 0.144 μg/g) lastly. Accumulation of heavy metals in soil is of concern due to their toxic effects on human and animals. The quality of ground water from the five boreholes studied was satisfactory with turbidity (T), electrical conductivity (EC) and heavy metals (HM’s) below the WHO limit. The water therefore may, according to the WHO Standards be safely used as a drinking water. The concern lies on pH which was slightly (0.5) below the standard. There is a serious need to monitor the ground water which is now used for drinking purposes. This study revealed that heavy metal pollution in soil from the abandoned Cu mine in Musina is a threat to the health of the community. Although pollution was between medium and low in the contamination index, it is therefore important for the Musina Municipality or mine owner of Musina (TVL) Development Co Ltd copper mine to advocate possible remedial actions which will safeguard the environment and human health. The tailing at Musina’s old Cu mine have high pH and they lack normal soil stabilization processes, as a result the tailing does not develop a good plant cover. Pollution of the ground water resources is also evident in the study area where there is seepage or ingress of polluted water to the underground aquifers. Small-scale mining in Musina is causing further degradation to the environment but it supports the South African Waste Hierarchy by promoting the reuse and recycling of the tailing and mine dumps for the production of bricks. Mine workers are exposed to the above mentioned toxic heavy metals daily. Medicine will not help stop the poisoning. The only way to stop the metal poisoning is to stop being exposed to the heavy metals. / Environmental Sciences / M. Sc. (Environmental Management)
326

The biomonitoring of heavy metal pollution in the wood and leaf chemistry of urban trees in Hong Kong

Ho, Ching-yee, Christina., 何靜宜. January 1999 (has links)
published_or_final_version / Geography and Geology / Master / Master of Philosophy
327

Photocatalytic treatment of industrial wastewater containing citric acid and toxic heavy metals

Baloyi, Siwela Jeffrey 12 1900 (has links)
M. Tech. (Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology| / The co-existence of organic acids and toxic heavy metals in natural water creates harmful effects on human, plants and animals. Therefore, it is necessary to treat organic acids and toxic heavy metal contaminated wastewater prior to its discharge to the environment. The aim of this study was to apply co-treatment of industrial wastewater containing citric acid and toxic heavy metals in single and binary systems using photocatalysis process. The hydrothermal method was used to synthesise dandelion-like TiO2 structures. Modifications of the dandelion-like TiO2 by deposition of gold nanoparticles and immobilisation on calcium alginate were done using deposition precipitation and one-step encapsulation methods, respectively. Dandelion-like TiO2 and dandelion-like TiO2 immobilised on calcium alginate (Alg/TiO2) were used as photocatalysts for Cr(VI), Hg(II) and citric acid removal from water. The results showed that the production of dandelion-like TiO2 structures strongly depends on the reaction time and synthesis temperature as key process parameters. The characterisation of the dandelion-like TiO2 by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and Brunauer-Emmett-Teller (BET) revealed the crystal structure, morphology, chemical composition and surface area. It was found that the efficiency of photocatalytic process depends on the type of pollutants, initial pH of the solution, photocatalyst dosage, contact time, substrate initial concentration, UV wavelength and light intensity. The reduction efficiency of Cr(VI) ion and citric acid increased with decreasing the initial pH values and initial concentration. On the other hand, Hg(II) reduction efficiency increased with increasing the initial pH values and initial concentration. In a binary system, the reduction of Cr(VI) and Hg(II) was found to be faster than in the single and ternary systems. The relationship of the chemical reaction rate of Cr(VI), Hg(II) and citric acid were expressed by the pseudo-first-order kinetic equation. Addition of ferric ions to Cr(VI)-citric acid complex and Hg(II)-citric acid complex enhanced the reduction of Cr(VI) and Hg(II), a complete reduction was accomplished within 30 and 60 minutes (min) of irradiation time, respectively. The reduction efficiency of both Cr(VI) and Hg(II) in the presence of citric acid in a solution was still significant after four times of Alg/TiO2 reuse. These results indicated that the UV/TiO2 photocatalysis process can be considered as a suitable method to reach a complete reduction of Cr(VI) and Hg(II) in the presence of citric acid in a solution.
328

Development of seaweed biomass as a biosorbent for metal ions removal and recovery from industrial effluent.

January 2000 (has links)
by Lau Tsz Chun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 134-143). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Contents --- p.vi / List of Figures --- p.xi / List of Tables --- p.xv / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Reviews --- p.1 / Chapter 1.1.1 --- Heavy metals in the environment --- p.1 / Chapter 1.1.2 --- Heavy metal pollution in Hong Kong --- p.3 / Chapter 1.1.3 --- Electroplating industries in Hong Kong --- p.7 / Chapter 1.1.4 --- "Chemistry, biochemistry and toxicity of selected metal ions: copper, nickel and zinc" --- p.8 / Chapter a. --- Copper --- p.10 / Chapter b. --- Nickel --- p.11 / Chapter c. --- Zinc --- p.12 / Chapter 1.1.5 --- Conventional physico-chemical methods of metal ions removal from industrial effluent --- p.13 / Chapter a. --- Ion exchange --- p.14 / Chapter b. --- Precipitation --- p.14 / Chapter 1.1.6 --- Alternative for metal ions removal from industrial effluent: biosorption --- p.15 / Chapter a. --- Definition of biosorption --- p.15 / Chapter b. --- Mechanisms involved in biosorption of metal ions --- p.17 / Chapter c. --- Criteria for a good metal sorption process and advantages of biosorption for removal of heavy metal ions --- p.19 / Chapter d. --- Selection of potential biosorbent for metal ions removal --- p.20 / Chapter 1.1.7 --- Procedures of biosorption --- p.23 / Chapter a. --- Basic study --- p.23 / Chapter b. --- Pilot-scale study --- p.25 / Chapter c. --- Examples of commercial biosorbent --- p.27 / Chapter 1.1.8 --- Seaweed as a potential biosorbent for heavy metal ions --- p.27 / Chapter 1.2 --- Objectives of study --- p.30 / Chapter 2. --- Materials and Methods --- p.33 / Chapter 2.1 --- Collection of seaweed samples --- p.33 / Chapter 2.2 --- Processing of seaweed biomass --- p.33 / Chapter 2.3 --- Chemicals --- p.33 / Chapter 2.4 --- Characterization of seaweed biomass --- p.39 / Chapter 2.4.1 --- Moisture content of seaweed biomass --- p.39 / Chapter 2.4.2 --- Metal ions content of seaweed biomass --- p.39 / Chapter 2.5 --- Characterization of metal ions biosorption by seaweed --- p.39 / Chapter 2.5.1 --- Effect of biomass weight and selection of biomass --- p.39 / Chapter 2.5.2 --- Effect of pH --- p.40 / Chapter 2.5.3 --- Effect of retention time --- p.41 / Chapter 2.5.4 --- Effect of metal ions concentration --- p.41 / Chapter 2.5.5 --- Effect of mix-cations and mix-anions on the removal capacity of selected metal ions by Ulva lactuca --- p.43 / Chapter 2.5.6 --- Recovery of adsorbed metal ions from Ulva lactuca (I): screening for suitable desorbing agents --- p.44 / Chapter 2.5.7 --- Recovery of adsorbed metal ions from Ulva lactuca (II): multiple adsorption-desorption cycles of selected metal ions --- p.45 / Chapter 2.5.8 --- Removal and recovery of selected metal ions from electroplating effluent by Ulva lactuca --- p.45 / Chapter 2.6 --- Statistical analysis of data --- p.46 / Chapter 3. --- Results --- p.47 / Chapter 3.1 --- Effect of biomass weight and selection of biomass --- p.47 / Chapter 3.1.1 --- Effect of biomass weight --- p.47 / Chapter 3.1.2 --- Selection of biomass --- p.58 / Chapter 3.2 --- Effect of pH --- p.58 / Chapter 3.2.1 --- Cu2+ --- p.58 / Chapter 3.2.2 --- Ni2+ --- p.61 / Chapter 3.2.3 --- Zn2+ --- p.61 / Chapter 3.2.4 --- Determination of optimal condition for biosorption of Cu2+ ,Ni2+ and Zn2+ by Ulva lactuca --- p.67 / Chapter 3.3 --- Effect of retention time --- p.67 / Chapter 3.4 --- Effect of metal ions concentration --- p.73 / Chapter 3.4.1 --- Relationship of removal capacity with initial concentration of metal ions --- p.73 / Chapter 3.4.2 --- Langmuir adsorption isotherm --- p.73 / Chapter 3.4.3 --- Freundlich adsorption isotherm --- p.77 / Chapter 3.5 --- Effect of mix-cations and mix-anions on the removal capacity of selected metal ions by Ulva lactuca --- p.81 / Chapter 3.5.1 --- Effect of mix-cations --- p.81 / Chapter 3.5.2 --- Effect of mix-anions --- p.85 / Chapter 3.6 --- Recovery of adsorbed metal ions from Ulva lactuca (I): screening of suitable desorbing agents --- p.91 / Chapter 3.6.1 --- Cu2+ --- p.91 / Chapter 3.6.2 --- Ni2+ --- p.91 / Chapter 3.6.3 --- Zn2+ --- p.91 / Chapter 3.7 --- Recovery of adsorbed metal ions from Ulva lactuca (II): multiple adsorption-desorption cycles of selected metal ions --- p.94 / Chapter 3.8 --- Removal and recovery of selected metal ions from electroplating effluent by Ulva lactuca --- p.97 / Chapter 4. --- Discussion --- p.106 / Chapter 4.1 --- Effect of biomass weight and selection of biomass --- p.106 / Chapter 4.1.1 --- Effect of biomass weight --- p.106 / Chapter 4.1.2 --- Selection of biomass --- p.107 / Chapter 4.2 --- Effect of pH --- p.109 / Chapter 4.3 --- Effect of retention time --- p.112 / Chapter 4.4 --- Effect of metal ions concentration --- p.114 / Chapter 4.4.1 --- Relationship of removal capacity with initial concentration of metal ions --- p.114 / Chapter 4.4.2 --- Langmuir adsorption isotherm --- p.114 / Chapter 4.4.3 --- Freundlich adsorption isotherm --- p.115 / Chapter 4.4.4 --- Insights from isotherm study --- p.117 / Chapter 4.5 --- Effect of mix-cations and mix-anions on the removal capacity of selected metal ions by Ulva lactuca --- p.118 / Chapter 4.5.1 --- Effect of mix-cations --- p.118 / Chapter 4.5.2 --- Effect of mix-anions --- p.120 / Chapter 4.6 --- Recovery of adsorbed metal ions from Ulva lactuca (I): screening of suitable desorbing agents --- p.122 / Chapter 4.7 --- Recovery of adsorbed metal ions from Ulva lactuca (II): multiple adsorption-desorption cycles of selected metal ions --- p.124 / Chapter 4.8 --- Removal and recovery of selected metal ions from electroplating effluent by Ulva lactuca --- p.126 / Chapter 5. --- Conclusion --- p.131 / Chapter 6. --- Summary --- p.134 / Chapter 7. --- References --- p.134 / Chapter 8. --- Appendixes --- p.144
329

A study on populations and contaminations of field Ganoderma lucidum.

January 2002 (has links)
by Ma Suet-yee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 119-131). / Abstracts in English and Chinese. / Acknowledgment --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Table of Contents --- p.vi / List of Tables --- p.x / List of Figures --- p.xii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Ganoderma lucidum --- p.1 / Chapter 1.1.1 --- History of Ganoderma lucidum --- p.1 / Chapter 1.1.2 --- Classification --- p.1 / Chapter 1.1.3 --- Macroscopic and microscopic structure --- p.2 / Chapter 1.1.4 --- Ganoderma lucidum as a pathogen --- p.3 / Chapter 1.1.5 --- Availability of tree hosts in Hong Kong --- p.4 / Chapter 1.1.6 --- Medicinal effects --- p.5 / Chapter 1.2 --- Study of Populations in Fungi --- p.6 / Chapter 1.2.1 --- Definition of Population --- p.6 / Chapter 1.2.2 --- Study of Fungal Populations --- p.7 / Chapter 1.2.3 --- Techniques for Population Studies in Fungi --- p.7 / Chapter 1.2.3.1 --- Somatic Incompatibility Test / Chapter 1.2.3.2 --- Isozyme Analysis / Chapter 1.2.3.3 --- Restriction Fragment Length Polymorphisms (RFLPs) / Chapter 1.2.3.4 --- Polymerase Chain Reaction (PCR) Amplification / Chapter 1.3 --- Mitochondrial DNA (mt-DNA) in Fungi --- p.14 / Chapter 1.3.1 --- Inheritance in mt-DNA --- p.15 / Chapter 1.3.2 --- Mitochondrial DNA in Population Studies --- p.15 / Chapter 1.3.2.1 --- Mitochondrial small-subunit (mt-SSU) rDNA / Chapter 1.3.2.2 --- Cytochrome oxidase 3 (cox3) / Chapter 1.4 --- Biodiversity study on Ganoderma species --- p.19 / Chapter 1.5 --- Environment Pollutants in Hong Kong --- p.20 / Chapter 1.5.1 --- Air quality in Hong Kong --- p.20 / Chapter 1.5.2 --- Soil quality in Hong Kong --- p.20 / Chapter 1.5.3 --- Toxicity of pollutants --- p.23 / Chapter 1.5.4 --- Accumulation of heavy metals by G. lucidum --- p.26 / Chapter 1.6 --- Objectives of Study --- p.27 / Chapter 1.7 --- Project Strategies --- p.28 / Chapter 1.7.1 --- Survey on distribution and collection of Ganoderma lucidum in Hong Kong --- p.28 / Chapter 1.7.2 --- Genetic divergences of G. lucidum mitochondrial genes --- p.28 / Chapter 1.7.3 --- Contaminations on field collected G. lucidum --- p.29 / Chapter 1.8 --- Significance of Study --- p.29 / Chapter Chapter 2 --- Materials and Methods --- p.30 / Chapter 2.1 --- Collection of Ganoderma lucidum in Hong Kong --- p.30 / Chapter 2.2 --- Tissue Isolation --- p.30 / Chapter 2.3 --- Somatic Incompatibility Test --- p.36 / Chapter 2.4 --- Molecular Identification --- p.40 / Chapter 2.4.1 --- Extraction of DNA --- p.40 / Chapter 2.4.2 --- Gel electrophoresis --- p.41 / Chapter 2.4.3 --- Strain authentication by arbitrarily primed polymerase chain reaction (APPCR) --- p.41 / Chapter 2.4.4 --- PCR of mt-SSU rDNA and --- p.43 / Chapter 2.4.5 --- Sequencing of mt-SSU rDNA and cox3 --- p.44 / Chapter 2.4.6 --- Comparison of G. lucidum complex with other Ganoderma and related species / Chapter 2. 4.7 --- Phylogenetic analyses --- p.46 / Chapter 2.5 --- Investigation of pollutants in Ganoderma lucidum collected in Hong Kong --- p.46 / Chapter 2.5.1 --- Metal analysis --- p.48 / Chapter 2.5.1.1 --- Acid digestion / Chapter 2.5.1.2 --- Statistical analysis / Chapter 2.5.2 --- Organic pollutant analysis --- p.49 / Chapter Chapter 3 --- Result --- p.52 / Chapter 3.1 --- Collection of Ganoderma lucidum in Hong Kong --- p.52 / Chapter 3.1.1 --- Field observation --- p.52 / Chapter 3.1.2 --- Macroscopic characteristics --- p.52 / Chapter 3.1.3 --- Microscopic characteristics --- p.53 / Chapter 3.2 --- Somatic Incompatibility Test --- p.56 / Chapter 3.3 --- DNA fingerprints by Arbitrarily-Primed PCR --- p.57 / Chapter 3.4 --- Sequencing of mt-SSU rDNA region of G. lucidum and related species --- p.60 / Chapter 3.4.1 --- Genetic variability in mt-SSU rDNA region of G. lucidum --- p.60 / Chapter 3.4.2 --- mt-SSU rDNA region of G. lucidum and other related species --- p.61 / Chapter 3.4.3 --- Phylogenetic analysis of mt-SSU rDNA region --- p.61 / Chapter 3.5 --- Sequencing of cox3 region --- p.71 / Chapter 3.5.1 --- Genetic variability in cox3 region of G. lucidum --- p.71 / Chapter 3.5.2 --- cox3 region of G. lucidum and other related species --- p.72 / Chapter 3.5.3 --- Phylogenetic analysis of cox3 region --- p.72 / Chapter 3.6 --- Metal content of field G. lucidum --- p.82 / Chapter 3.7 --- Organic pollutants in field collected G. lucidum --- p.90 / Chapter Chapter 4 --- Discussion --- p.93 / Chapter 4.1 --- Collection of Ganoderma lucidum in Hong Kong --- p.93 / Chapter 4.1.1 --- Differentiation of G. lucidum and related species in the G lucidum species complex --- p.93 / Chapter 4.1.2 --- Field observation --- p.94 / Chapter 4.2 --- Biodiversity of populations of G. lucidum in Hong Kong --- p.95 / Chapter 4.2.1 --- Individualism of G. lucidum --- p.95 / Chapter 4.2.2 --- Genetic variability in mt-SSU rDNA region of G. lucidum --- p.96 / Chapter 4.2.3 --- Genetic variability in cox3 region of G. lucidum --- p.98 / Chapter 4.2.4 --- Lineages of G. lucidum collected in Hong Kong --- p.100 / Chapter 4.2.5 --- Cryptic phylogenetic species --- p.101 / Chapter 4.3 --- Contamination of field collected Ganoderma lucidum in Hong Kong --- p.106 / Chapter 4.3.1 --- Metal contents in field collected G. lucidum in Hong Kong --- p.106 / Chapter 4.3.1.1 --- Metal contents of G. lucidum fruiting bodies collected at each site / Chapter 4.3.1.2 --- General discussion of metals / Chapter 4.3.1.3 --- Consumption of field collected G. lucidum fruiting bodies / Chapter 4.3.2 --- Comparison of metal contents between field collected Hong Kong G. lucidum with other mushrooms collected from other places --- p.112 / Chapter 4.3.3 --- Survey of organic pollutants in field collected G. lucidum in Hong Kong --- p.113 / Chapter Chapter 5 --- Conclusion --- p.116 / Chapter Chapter 6 --- Further investigation --- p.118 / Chapter Chapter 7 --- Reference --- p.119
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Effect and uptake of cadmium and lead mixtures on selected vegetables : environmental and public health implications

Nwosu, Julius U. 11 December 1992 (has links)
Graduation date: 1993

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