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Aswan, Egypt

Shindy H.A.,Aswan University
Mini-Reviews in Organic Chemistry | Year: 2012

In this paper, the basic information, fundamental understanding, principles and/or knowledge of color, dyes and pigments chemistry via multi choice questions and their answers have been reviewed. More than two hundred multi choice questions and their answers have been represented in this paper review. The paper includes topics like, the relation between color and constitution and/or Witt's theory, fibers, nomenclature of dyes, definitions for dyes and pigments, types of dye binding to the fibers and other definitions and vital information in color, dyes and pigments chemistry. The paper also involves synthesis, properties, classifications and uses of many aromatic and/or heterocyclic dyes. Such dyes, like nitro dyes, nitroso dyes, azo dyes, diarylmethane dyes, triarylmethane dyes, anthraquinone dyes, cyanine dyes, azine dyes, phthaleine dyes, rehodamine dyes and indigoid dyes. Reviewing the basics, fundamental principles and/or the understanding of color, dyes and pigments chemistry via multi choice questions and their answers are considered a new and/or novel idea of reviewing which have not mentioned in the literature before. © 2012 Bentham Science Publishers.

Shindy H.A.,Aswan University
Mini-Reviews in Organic Chemistry | Year: 2012

Some essential basics, mechanisms and properties in the chemistry of cyanine dyes are reviewed, explained and/or illustrated in the paper. This involves and/or covers the generic structure of cyanine dyes, mesomeric structures of cyanine dyes, charge of the dye unit, quaternary salts used in the preparation of cyanine dyes, mechanism of styryl cyanine dyes, mechanism of aza-styryl cyanine dyes, mechanism of acyclic merocyanine dyes, mechanism of cyclic merocyanine dyes, mechanism of aromatic squarylium cyanine dyes, mechanism of heterocyclic squarylium cyanine dyes, acid-base properties of cyanine dyes, determination of the pKa values of cyanine dyes, solvatochromism, general and specific solvent effects, mixed solvent effects, advantages of cyanine dyes and disadvantages of cyanine dyes. In addition, in the introduction section of this review article some light is shed on the uses and applications of cyanine dyes. © 2012 Bentham Science Publishers.

Darwish M.A.G.,Aswan University
International Journal of Sediment Research | Year: 2013

The goal of the present work is to perform a geochemical assessment of High Dam Lake bottom sediments for determining the fate, dispersion and levels of trace elements causing environmental pollution, and provided an access to their probable sources. The sediment samples were analyzed using ICP-MS for 20 elements; Ag, Ba, Cr, Cu, Ga, Hf, Mn, Pb, Rb, Sc, Se, Sn, Sr, Ta Th Ti, Tl, U, V and Zr, and their obtained data were treated using statistical, graphical and mapping techniques. The results showed the data set of all analyzed elements affected by outliers and extreme values that caused deviation away from normality. Kruskal-Wallis test revealed that median of some trace element levels in Lake sediments, was not significantly different and other elements rejected the Null hypothesis. Most analyzed elements had high values of median and mean in sediments of Lake Nubia rather than Lake Nasser and their normalization gave the same results of calculated environment factors. Subsequently, Lake Nubia sediments possessed high combined EF levels of Th, Sc, Sn, Ag, Zr, Hf, Ta, Sr, U, Ti, V, Cr, and Mn, causing significant contamination, which was great potentially related to industrial, agricultural, urbanization and mining activities. Whereas, combined EF of Se, Cu, Ga, Pb, Ba, Rb, and Tl, which are highly elevated in southern Lake Nasser sediments owing to their source are great possibly derived from Lake Nubia and geogenic activities. With decreasing distance towards the High Dam body, the contaminant elements were diminished due to reduction in the environmental factors and Sudanese pollution sources leading to the northern Lake Nasser considered to be less contaminated. Overall, the present study is an environmental alert for contaminated sediments that carried contaminants and considered the secondary source of pollution impact on ecosystem, and subsequently, their environmental risk on Human health. © 2013 International Research and Training Centre on Erosion and Sedimentation and the World Association for Sedimentation and Erosion Research.

Elsawy M.B.D.,Aswan University
Geosynthetics International | Year: 2013

Construction of embankments on soft natural soil may be a challenge, owing to its low shear strength and high compressibility. Stone columns, which depend on lateral support from the soft ground, have been utilised to accelerate foundation consolidation, and to increase foundation bearing capacity. To keep the drainage function, and to improve the stone columns as reinforcing elements, geosynthetics are used for column encasement. In this research, the behaviour of full-scale unreinforced and reinforced Bremerhaven clay with conventional and geogrid-encased stone columns under embankment loads is analysed numerically. The consolidation analysis is applied to investigate the long-term behaviour of the clay. The results show that the stone columns in the Bremerhaven clay increase the bearing capacity and accelerate the reduction of excess pore water pressure of the foundation. Once the stone columns are encased, more improvement occurs in their performance in soft soil. The analyses also indicate that stress concentration generation in the stone columns contributes significantly to the acceleration of soil consolidation. © 2013 Thomas Telford Ltd.

Aim: To study the prevalence of pathogenic coagulase positive, methicillin-resistant Staphylococcus aureus (MRSA) in poultry meat and its products. Materials and Methods: A total of 125 poultry samples were collected during 2012 in Qena governorate for presence of pathogenic coagulase positive, methicillin-resistant staphylococcus aureus (MRSA). Samples were taken from freshly slaughtered whole chicken carcasses (25/125), chicken portions (25/125), chicken luncheon (25/125), chicken sausages (25/125) and chicken burgers (25/125). Results: It was observed that 44% (11/25), 52% (13/25), 40% (10/25), 24% (6/25) and 44% (11/25) of bacterial isolates were positive for methicillin-resistance tests for freshly slaughtered whole chicken carcasses, chicken portions, chicken luncheon, chicken sausages and chicken burgers respectively. Higher contamination rate of MRSAwas found in raw poultry meat and the lower rate in poultry meat products subjected to heat treatment and preservatives. Conclusion: Poultry meat and its products were considered as an important source of spreading of MRSAin humans. Hence, strict hygienic measures should be taken in poultry slaughter houses and in food preparing establishments.

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