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Polymers are long chains of repeating chemical units called monomers. They share several characte... more Polymers are long chains of repeating chemical units called monomers. They share several characteristics including macro and micro properties, electrical transport properties, semiconducting properties and optical properties. Polymers can be synthesized by chemical and electrochemical polymerization. Polymers prepared through these methods can also be characterized by their electrical, optical, mechanical and electrochemical means.

International Journal of Technology Enhancements and Emerging Engineering Research, 2014

This article reviews about naturally occurring conducting polymer, Melanin. In this paper detaile... more This article reviews about naturally occurring conducting polymer, Melanin. In this paper detailed explanation was included conducting polymers that have been developed with wide range of properties and potential applications due to their chemical, mechanical, optical and electrical properties such as sensors, electromechanical devices, batteries and electro chemical cell. In addition ist was also describer about Melanins that is serve as a free radical scavengers, antioxidants and photoconductors. However, some researchers have shown that cells containing small amount of melanin are more susceptible to damage from irradiation. This observation has been linked to iron content of melanin, in that when melanin is saturated with transition metal ions like iron it may actually produce free radicals and therefore accelerates cell death rather than protecting it. Therefore it is advisable to protect the melanin pigment from saturation with such transition metal ions (abstact).

This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosio... more This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosion is one of the greatest civil engineering challenges all over the world. Corrosion is caused by steel over time restoring to its natural state of iron steel. Several protection methods against Corrosion have been developed including cathodic protection and using inhibitors and coating. Hot wax dip method and sealing service with poly sulfide are two popular protection methods of corrosion.

American Scientific Research Journal for Engineering, Technology, and Sciences, 2014

This study focuses on the importance of electrochemical pretreatment of glassy carbon electrode (... more This study focuses on the importance of electrochemical pretreatment of glassy carbon electrode (GCE) for the determination of chloramphenicol (CAP) in pharmaceutical formulations using square wave voltammeter. Electrochemical pretreatment of the electrode greatly enhanced the reduction peak current (Ip) of CAP that it shows a reduction peak current response at -0.032 V vs. Ag/AgCl at the GCE in 0.05 M acetate buffer of pH 5. Detailed experiments were carried out to establish the electrochemical property, the optimal buffer and its pH, electrode pretreatment potential, effect of concentration and square wave voltammetric parameters. Following optimization of the instrumental parameters and pH of buffer solution, the peak current response for the reduction of CAP shows an enhanced response, 5.82 times greater than the bare GCE. The method was successfully applied to three CAP containing pharmaceutical samples: CAP eye drop, CAP palmitat oral suspension and CAP as sodium succinate and...

International Journal of Research -GRANTHAALAYAH, 2014

This paper reviews the characterization and chemical/biochemical analysis of natural dyes. Extrac... more This paper reviews the characterization and chemical/biochemical analysis of natural dyes. Extraction of colorants from different natural sources, effects of different mordents and application of binary mixture of natural dyes. Natural dyes are different sources such as plant dyes animal dyes mineral dyes etc. and characteristics of natural dyes such as chemical/biochemical analysis by using UV-visible spectroscopic and chromatographic analysis.

International Journal of Innovation and Scientific Research, Sep 10, 2014

This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosio... more This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosion is one of the greatest civil engineering challenges all over the world. Corrosion is caused by steel over time restoring to its natural state of iron steel. Several protection methods against Corrosion have been developed including cathodic protection and using inhibitors and coating. Hot wax dip method and sealing service with poly sulfide are two popular protection methods of corrosion.

This paper presents the concentration of Cu, Zn, Fe, Pb and Cd in vegetables, soil and water samp... more This paper presents the concentration of Cu, Zn, Fe, Pb and Cd in vegetables, soil and water samples. Samples were collected from Mayham (Adigrat, Tigray region). Total acid (7ml mixture of HNO 3 , H 2 SO 4 , HClO 4) digestion method was employed and determination was made by flame atomic absorption spectroscopy. The percentage recoveries of the metals were in the range of 89% to 100% in vegetable, 84% to 100% in water and 82% to 103% in soil sample. The range of concentration(µg/g) of the metals on dry weight basis are: Cd 1.18-1.45 in vegetables, 1 in soil and 9 in water; Cu 9-18 in vegetables, 15-17 in soil and 4.3 in water; Pb 1.67-5.01 in vegetable, 3-5 in soil and 2.6 in water; Zn 40-398.5 in vegetable, 59-66.8 in soil and 9.2 in water; Fe 218.25-4987.5 in vegetables, 23705.75 – 29248.5 in soil and 177.5 in water sample. The result obtained imples that the plant is rich in iron, zinc and copper and has small concentration of non-essential trace elements like lead and cadmium.

OALib, 2014

The present work reports the oxidative synthesis of poly aniline using K 2 Cr 2 O 7 as an oxidizi... more The present work reports the oxidative synthesis of poly aniline using K 2 Cr 2 O 7 as an oxidizing agent and H 2 SO 4 as dopant. The synthesized polymer was characterized by solubility test and UVvisible spectroscopic technique. The synthesized polymer (poly aniline) was insoluble in ethanol, acetone, benzene and water. The absorbance of UV-visible spectra shows two reductive peaks at some wake length. The band observed at 327 -365 nm for the PANI samples corresponds to n-p * transitions of aniline and the broad band at 600 -620 nm is due to n-p * transitions of quinine-imine groups.

Polymers are long chains of repeating chemical units called monomers. They share several characte... more Polymers are long chains of repeating chemical units called monomers. They share several characteristics including macro and micro properties, electrical transport properties, semiconducting properties and optical properties. Polymers can be synthesized by chemical and electrochemical polymerization. Polymers prepared through these methods can also be characterized by their electrical, optical, mechanical and electrochemical means.

International Journal of Technology Enhancements and Emerging Engineering Research, 2014

This article reviews about naturally occurring conducting polymer, Melanin. In this paper detaile... more This article reviews about naturally occurring conducting polymer, Melanin. In this paper detailed explanation was included conducting polymers that have been developed with wide range of properties and potential applications due to their chemical, mechanical, optical and electrical properties such as sensors, electromechanical devices, batteries and electro chemical cell. In addition ist was also describer about Melanins that is serve as a free radical scavengers, antioxidants and photoconductors. However, some researchers have shown that cells containing small amount of melanin are more susceptible to damage from irradiation. This observation has been linked to iron content of melanin, in that when melanin is saturated with transition metal ions like iron it may actually produce free radicals and therefore accelerates cell death rather than protecting it. Therefore it is advisable to protect the melanin pigment from saturation with such transition metal ions (abstact).

This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosio... more This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosion is one of the greatest civil engineering challenges all over the world. Corrosion is caused by steel over time restoring to its natural state of iron steel. Several protection methods against Corrosion have been developed including cathodic protection and using inhibitors and coating. Hot wax dip method and sealing service with poly sulfide are two popular protection methods of corrosion.

American Scientific Research Journal for Engineering, Technology, and Sciences, 2014

This study focuses on the importance of electrochemical pretreatment of glassy carbon electrode (... more This study focuses on the importance of electrochemical pretreatment of glassy carbon electrode (GCE) for the determination of chloramphenicol (CAP) in pharmaceutical formulations using square wave voltammeter. Electrochemical pretreatment of the electrode greatly enhanced the reduction peak current (Ip) of CAP that it shows a reduction peak current response at -0.032 V vs. Ag/AgCl at the GCE in 0.05 M acetate buffer of pH 5. Detailed experiments were carried out to establish the electrochemical property, the optimal buffer and its pH, electrode pretreatment potential, effect of concentration and square wave voltammetric parameters. Following optimization of the instrumental parameters and pH of buffer solution, the peak current response for the reduction of CAP shows an enhanced response, 5.82 times greater than the bare GCE. The method was successfully applied to three CAP containing pharmaceutical samples: CAP eye drop, CAP palmitat oral suspension and CAP as sodium succinate and...

International Journal of Research -GRANTHAALAYAH, 2014

This paper reviews the characterization and chemical/biochemical analysis of natural dyes. Extrac... more This paper reviews the characterization and chemical/biochemical analysis of natural dyes. Extraction of colorants from different natural sources, effects of different mordents and application of binary mixture of natural dyes. Natural dyes are different sources such as plant dyes animal dyes mineral dyes etc. and characteristics of natural dyes such as chemical/biochemical analysis by using UV-visible spectroscopic and chromatographic analysis.

International Journal of Innovation and Scientific Research, Sep 10, 2014

This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosio... more This paper review theory and Mechanism of Corrosion as well as ways of prevented method. Corrosion is one of the greatest civil engineering challenges all over the world. Corrosion is caused by steel over time restoring to its natural state of iron steel. Several protection methods against Corrosion have been developed including cathodic protection and using inhibitors and coating. Hot wax dip method and sealing service with poly sulfide are two popular protection methods of corrosion.

This paper presents the concentration of Cu, Zn, Fe, Pb and Cd in vegetables, soil and water samp... more This paper presents the concentration of Cu, Zn, Fe, Pb and Cd in vegetables, soil and water samples. Samples were collected from Mayham (Adigrat, Tigray region). Total acid (7ml mixture of HNO 3 , H 2 SO 4 , HClO 4) digestion method was employed and determination was made by flame atomic absorption spectroscopy. The percentage recoveries of the metals were in the range of 89% to 100% in vegetable, 84% to 100% in water and 82% to 103% in soil sample. The range of concentration(µg/g) of the metals on dry weight basis are: Cd 1.18-1.45 in vegetables, 1 in soil and 9 in water; Cu 9-18 in vegetables, 15-17 in soil and 4.3 in water; Pb 1.67-5.01 in vegetable, 3-5 in soil and 2.6 in water; Zn 40-398.5 in vegetable, 59-66.8 in soil and 9.2 in water; Fe 218.25-4987.5 in vegetables, 23705.75 – 29248.5 in soil and 177.5 in water sample. The result obtained imples that the plant is rich in iron, zinc and copper and has small concentration of non-essential trace elements like lead and cadmium.

OALib, 2014

The present work reports the oxidative synthesis of poly aniline using K 2 Cr 2 O 7 as an oxidizi... more The present work reports the oxidative synthesis of poly aniline using K 2 Cr 2 O 7 as an oxidizing agent and H 2 SO 4 as dopant. The synthesized polymer was characterized by solubility test and UVvisible spectroscopic technique. The synthesized polymer (poly aniline) was insoluble in ethanol, acetone, benzene and water. The absorbance of UV-visible spectra shows two reductive peaks at some wake length. The band observed at 327 -365 nm for the PANI samples corresponds to n-p * transitions of aniline and the broad band at 600 -620 nm is due to n-p * transitions of quinine-imine groups.