Thesis (M. Sc.)--University of Hong Kong, 1993.

Thesis (M.Sc.)--Memorial University of Newfoundland, 2001. / Includes bibliographical references.

Magister Scientiae - MSc / The current study investigated application of natural adsorbents in brine treatment. Brines are hypersaline waters generated in power stations and mining industries rich in Mg2+, K+, Ca2+, Na+, SO4 2- , Cl- and traces of heavy metals, thus there is a need for these brines to be treated to recover potable water and remove problematic elements. Natural adsorbents have been successfully used in waste water treatment because of their high surface area and high adsorptive properties when they are conditioned with acid or base. The investigation of pH showed that natural adsorbents did not perform well at low pH of 4 and 6. The adsorbents were able to work efficiently at the natural pH of 8.52 of the brine solution. These results show that natural adsorbents hold great potential to remove cationic major components and selected heavy metal species from industrial brine waste water. Heterogeneity of natural adsorbents samples, even when they have the same origin, could be a problem when wastewater treatment systems utilizing natural clinoptilolite and bentonite are planned to be developed. Therefore, it is very important to characterize the reserves fully in order to make them attractive in developing treatment technologies. / South Africa

A study has been made of three organic complexing reagents , namely dithizone, oxine and cupferron with a view to developing suitable methods for the separation and concentration of Zn, Co, Ni, Pb, Cu, Mn, Ti , V and Mo prior to the spectrometric determination of their concentrations. In particular the influence of pH on the chloroform extraction of ditihizonates, oxinates and cupferrates from aqueous tartrate and citrate solutions and the separation of iron by oxine extraction has been investigated. The development of a method for the chemical concentration and spectrcgraphic determination of Zn, Co, Ni, Pb, Ti, V and Mo is described and the possibility of determining Nn and Cu flame photometrically as part of the analysis scheme is demonstrated. A specially designed slide rule for the calculation of spectrographic results is described. A direct reading spectrometric method for the determination of Zn, Pb and Cu in plant material is presented. The analysis of plant ash for zinc using the 2138 . 6A spectrum line has been studied and a simple, rapid analysis method is described.

No description available.

No description available.

Bush tea (Athrixia phylicoides DC.) is a herbal beverage and medicinal plant indigenous to South Africa. A trial was conducted to determine the effect of micronutrients on the plant growth and quality of bush tea. The trial was laid out in a completely randomized block design with five replicates. Treatments consisted of single applications of Zinc (Zn), Copper (Cu), Boron (Bo), Iron (Fe) and Magnesium (Mg) at three levels (50ml/l, 100ml/l and 150ml/l) and a combination of all micronutrients. A control treatment with no spray was also included. Leaf analysis was conducted using Varian Liberty series II instrument. Total polyphenols were determined using the Folin Ciocalteau method and tannins were determined using Vanillin HCl method. Bush tea samples (one leaf per sample) were analysed using head space solid phase micro-extraction gas chromatography (HS-SPME-GC-MS). Results of this study demonstrated that application of micronutrients increased the total polyphenols, tannins and total flavonoids in bush tea, with most of the increase in total polyphenols (77.5-93.7 mg/g) occurring in combination B + Zn + Fe + Cu + Mg treatment, increase in tannins (87.3-99.5 mg/g) occurring in copper treatment and increase in total flavonoids (164.6-176.6 mg/g) occurring in mixture (B + Zn + Fe + Cu + Mg) treatment. Results also show a significant increase in the quality and plant growth of bush tea. Five major compounds were identified (>80% identification probability) namely alpha-pinene, beta-pinene, myrcene, beta-caryophyllene and caryophyllene oxide. Linear relationship between percentage leaf tissues and treatments levels of micronutrients in bush tea was also observed. Boron and copper treatments showed strong linear correlation with a positive relationship between treatments levels and leaf percentage. Therefore, for improved total polyphenols content in bush tea leaves, a combination of (B + Zn + Fe + Cu + Mg) is recommended. Tannin content in bush tea leaves were significantly increased at Cu50 ml/l, Cu100 ml/l and Cu150 ml/l. For improved total flavonoids content in bush tea leaves, a combination of foliar spray of (B + Zn + Fe + Cu + Mg) is recommended. The LC-MS observations from the study showed no significant qualitative difference between control and micronutrient treatments with these treatments showing similar number of peaks. There was a significant quantitative difference between control and where magnesium peaks applied at adequate rates at (50 ml/l and 100 ml/l) and combination of (B + Zn + Fe + Cu + Mg) applied at (10 ml/l and 20 ml/l) / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)

A nitrogen-cooled and an argon-cooled hydrogen flame have been used for the determination of sulfur containing species in solids by molecular emission cavity analysis (MECA). The argon-cooled flame is much more sensitive for the determination of SO₄²⁻. In a solid mixture containing S₈, S²⁻, SO₃²⁻, and SO₄²⁻, the presence of one or more of these sulfur containing species can be determined with the argon-cooled flame. The nitrogen-cooled flame can be useful, for example, in the determination of a mixture of S₈ and SO₃²⁻ in a solid matrix. All these sulfur containing species can be quantitatively determined in the argon-cooled flame in the concentration range from about 10 ppm to 5000 ppm. The variation from 10 percent to 30 percent in the reproducibility of these measurements has been attributed to the non-homogeneity of the solid materials and the small sizes required. Sulfur dioxide has been used for the reduction of ammoniacal copper(II) solutions to solutions containing various copper(I) compounds. These copper(I) compounds can be reduced further to copper metal by varying the solution conditions. The mechanisms of the reactions involved must be understood before they can be successfully used for the large scale production of copper. Porth et al.'s method was followed for the synthesis of Cu(I) intermediates. Several compounds were isolated and their compositions determined. The changes in the relative concentrations of Cu(I) and Cu(II) are also important for unraveling the kinetics and mechanisms of these reactions. A simple spectrophotometric method using 2,9-dimethyl-1,10-phenanthroline was developed to monitor the Cu(I) concentration in solution. The sensitivity of the method is sufficient to determine 10⁻⁵ M Cu(I) in the presence of Cu(II); SO₂, however, interferes with the method. Other possible methods including the use of a mixture of EDTA and 2,9-dimethyl-1,10-phenanthroline were also examined. Evidence is presented for the formation of a ternary complex of copper(I), 2-9-dimethyl-1,10-phenanthroline, and EDTA. The possibility of using a mixture of Cu(II) and 2,9-dimethyl-1,10-phenanthroline to determine SO₂ was tested. Oxygen was found to interfere with this method.

This study was designed to examine the influence of Cu deficiency on the binding, uptake, and degradation of apolipoprotein E-free high density lipoproteins (apo E-free HDL) in cultured rat hepatic parenchymal cells. The binding of apo E-free HDL during time course studies was slightly but significantly increased in cells derived from Cu-deficient rats. In saturation studies, the amount of surface-bound apo E-free HDL appeared to be saturable, although no difference was observed between Cu-deficient and adequate animals. The amount of total and specific cell-associated uptake of apo E-free HDL was significantly increased in hepatic parenchymal cells of Cu-deficient animals. The present data suggest that hepatic uptake of the HDL protein moiety may be increased in rats fed a diet deficient in copper.

Since the White River in east central Indiana is a source of water for human use, the quality of its water is an important concern. Certain heavy metals, when present in high enough concentrations may cause discoloration, foul taste, or may even be a health hazard to man. The particular metals of interest in this investigation are iron, copper, mercury, lead, chromium, nickel, and cobalt. The present study is concerned with the measurement of the concentrations of these metals in the waters and sediment of the White River at Muncie, Indiana.The analyses for the metals listed were performed via appropriate standard methods, involving principally atomic absorption spectroscopy. Four river sites in the Muncie vicinity were sampled daily for a. week, one week per month, for two months, using techniques designed both for convenience and representative character of samples.The end-products of this study are a, comparison of the heavy metal concentrations in the White River with values from other studies and a discussion of the many variables needed to present a true picture of the metallic content of the river water.