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41.
Ozonation in batch experiments were conducted at elevated temperatures to study the influence of temperature on the efficiency of ozonation. The effect of temperature on ozonation was determined by measuring the extent of colour removal and the reduction of chemical oxygen demand (COD) and total organic carbon (TOC) of a textile waste effluent. It was found that increasing the temperature causes a decrease in the levels of colour, COD and TOC. Complete mineralisation of the dye molecule, however, did not occur to an appreciable extent. The efficiency of colour removal was 71.3%, whilst the COD and TOC reduction efficiency was 20.3 and 19.3%, respectively, at the highest temperature studied (50 °C). The removal efficiency of COD, however, did not improve significantly when the temperature was increased from 40 to 50 °C. 相似文献
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A new monomer, N-succinimido (N) thiocarbonyl acrylamide is formed when succinic anhydride, thiourea, and acryloyl chloride are condensed in mole proportions at low temperatures. The monomer is polymerized and graft copolymerized onto poly(vinyl alcohol) using a potassium bromate-thiourea redox system. Acrylamide is also similarly grafted to poly(vinyl alcohol) using the same initiator system. Grafting efficiencies of the monomers are determined from the elemental analyses data of the graft copolymers. Thermal behavior of the polymers are derived from the DSC thermograms of the polymers. © 1993 John Wiley & Sons, Inc. 相似文献
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E. K. Girija S. Narayana Kalkura P. Ramasamy 《Journal of materials science. Materials in medicine》1995,6(11):617-619
Cystine is an amino acid, which is a constituent of the urinary stones. It also is deposited in eyes, thyroid glands, bone marrow and white blood corpuscles. Crystals of cystine have been grown by both solution and gel methods. Small bunched hexagonal crystals, along with many other morphological crystals of size 0.3 mm across, were obtained. The crystals were analysed by X-ray diffraction and IR analyses. 相似文献
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