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The use of single-source molecular precursors for lead chalcogenide thin films by CVD or as nanoparticles by solution methods is reviewed. The potential applications of these materials in solar energy are discussed along with the relative advantages of the various methods.

This study focused upon the determination of physicochemical and microbial properties, including metals, selected anions and coliform bacteria in drinking water samples from hand-dug wells in the Kumasi metropolis of the Republic of Ghana. The purpose was to assess the quality of water from these sources. Ten different water samples were taken from different parts of Kumasi, the capital of the Ashanti region of Ghana and analyzed for physicochemical parameters including pH, electrical conductivity, total dissolved solids, alkalinity total hardness and coliform bacteria. Metals and anions analyzed were Ca, Mg, Fe, Mn, NO3−, NO2−, SO42−, PO42−, F− and Cl−. Bacteria analysed were total coliform and Escherichia coli.The data showed variation of the investigated parameters in samples as follows: pH, 6.30–0.70; conductivity (EC), 46–682 μS/cm; PO43−, 0.67–76.00 mg/L; F−, 0.20–0.80 mg/L; NO3−, 0–0.968 mg/L; NO2−, 0–0.063 mg/L; SO42−, 3.0–07.0 mg/L; Fe, 0–1.2 mg/L; Mn, 0–0.018 mg/L. Total coliform and Escherichia coli were below the minimum detection limit (MDL) of 20 MPN per 100 ml in all the samples. The concentrations of most of the investigated parameters in the drinking water samples from Ashanti region were within the permissible limits of the World Health Organization drinking water quality guidelines.

The objective of this study was to find out if the sawdust generated from some of the Ghanaian wood species can be used in the cultivation of pleurotus ostreatus (oyster mushroom) and their subsequent effect on the quality and yield of the mushrooms produced. Sawdust from three Ghanaian wood species (Triplochiton scleraxylon, Ceiba pentandra and Terminalia superba) were collected and their cellulose, hemicelluloses, lignin and nitrogen contents determined using standard methods. Triplochiton scleraxylon gave 46.76%, 15.69%, 27.55%, 0.01% w/w, Ceiba pentandra gave 44.79%, 15.32%, 34.08%, 0.02% w/w and Terminalia superba gave 46.64%, 16.29%, 31.17%, 0.02% w/w of the cellulose, hemicelluloses, lignin and nitrogen content respectively. Compost was then made from each of the wood and used as substrate for the cultivation of pleurotus ostreatus. The highest yield of mushroom was obtained from T. scleraxylon 334g followed by T. superba 277 g and C. pentandra gave the lowest yield of 193 g fresh weight after 3 flushes. The proximate composition of the mushrooms produced gave crude protein ranging 16.33 - 18.20, fat 1.67 - 2.07, carbohydrate 40.86 - 50.53, fibre 4.14 - 6.73 and ash content of 4.40% - 5.80%. The report has shown that the yield and nutritional content of the oyster mushroom on sawdust depends on the chemical constituents such as the cellulose content, the hemicellulose content, the lignin content, the nitrogen content of the particular substrate used. Triplochiton scleraxylon gave the best yield and nutritional content, considering that these substrates are freely available and regarded as “waste”, it can be used to cultivate edible mushrooms to supplement nutritional requirement and source of income to make life better for many people