VOLUME 33, NO5, OCT 2011
123
 
Two Dimensional X-Ray Diffraction (2D-XRD) studies on Olivine of U.S.A.

MASOOM YASIN ZAI ,SALMA JABEEN ,SYED MOHSIN RAZA ,KURT ERLACHER ,MUHAMMAD ASHFAQ AHMED ,

The Olivine (Mg, Fe) 2SiO4 of USA has been studied with two dimensional X-ray diffracto meter (D8 discover with GADDS). The two distinct phases of orthorhombic structure, one with Mg8 [Fe2 SiO4] and the other with Mg2 SiO4 is observed. We also observed phase transitions due to presence of iron and Silicon preferably the structural change of Mg8[Fe2 SiO4] from orthorhombic to spinnel like (spinnel chord) structure. Magnesium ions in Mg8[Fe2 SiO4] shuffle, arrange at the five vertices of a pentagon and the remaining three at the central but with displaced position from the plane of the pentagon, Thus resulting into a three dimensional spinnel chord like structure. We evidenced the same from diverse orientations of phase peaks and indeed from Kossel lines.
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Modeling of Cd(II) Sorption on Mixed Oxide

SYED MUSTAFA ,MUHAMMAD SAFDAR ,ABDUL NAEEM ,KHIZAR HUSSAIN SHAH ,MUHAMMAD WASEEM ,SAMAD YAR HUSSAIN ,

Mixed oxide of iron and silicon (0.75M Fe(OH)3:0.25M SiO2) was synthesized and characterized by various techniques like surface area analysis, point of zero charge (PZC), energy dispersive X-rays (EDX) spectroscopy, Thermogravimetric and differential thermal analysis (TG-DTA), Fourier transform infrared spectroscopy (FTIR) and X-rays diffraction (XRD) analysis. The uptake of Cd2+ ions on mixed oxide increased with pH, temperature and metal ion concentration. Sorption data have been interpreted in terms of both Langmuir and Freundlich models. The Xm values at pH 7 are found to be almost twice as compared to pH 5. The values of both DH and DS were found to be positive indicating that the sorption process was endothermic and accompanied by the dehydration of Cd2+. Further, the negative value of DG confirms the spontaneity of the reaction. The ion exchange mechanism was suggested to take place for each Cd2+ ions at pH 5, whereas ion exchange was found coupled with non specific adsorption of metal cations at pH 7.
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Optimal Method for Preparation of Magnetite Nanoparticles

AMINUR RAHMAN ,NAZIR SHAH KHATTAK ,UMAR SAEED KHAN ,FARIDULLAH KHAN ,

This paper deals with the synthesis and characterization of magnetite nanoparticles via the controlled modified chemical coprecipitation method using ferrous and ferric salt solution in alkaline medium with out any surfactant addition. The nanoparticles of 9–14 nm in size were prepared under non-oxidized environment and characterized by transmission electron microscopy, energy dispersive X-rays spectrometry, X-ray diffraction and BET surface area analyzer. The reaction temperature and the stirring rate during the precipitation were found to be crucial in limiting their size and size distribution. Low temperature and high stirring rate are the appropriate conditions for the synthesis of these particles.
Pages(628)
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Preparation of Ethylcellulose Latex by Aqueous Dispersions: Importance of the Particle Size and Plasticizer

HUI LIU ,CHENGZHI CHUAI ,KALSOOM MAHMOOD ,MAHMOOD IQBAL ,MUHAMMAD AIJAZ ,YAN HUANG ,

Based on phase transfer processes ethylcellulose (EC) latex was prepared using dibutyl sebacate (DBS) as plasticizer and oleic acid, ammonia water as an emulsifier to evaluate film-formation properties. Atomic force microscopy was used to characterize the surface features, practical size and differential scanning colorimetry was employed to investigate the effect of plasticizer on glass transition temperature of the resulting materials.  The influences of emulsifier concentration on the particle size and on the viscosity were studied. The viscosity initially showed a decreased tendency and then increased linearly with increasing emulsifier concentration. On the other hand, the surface tension decreased considerably up to about 4 wt%, and then it almost remains unchanged with increasing emulsifier concentration.  The polymer particle size was identified to be a very crucial formulation parameter, determining the resulting film coating structure and properties. Importantly the particle size decreased systemically with increasing emulsifier concentration up to about 2 wt% and then increased markedly with increasing emulsifier concentration. In addition, the results indicated that the incorporation of polymeric plasticizer substantially reduced the glass transition temperature (Tg) and softening temperature. Moreover, the home-synthesized EC latex could be used effectively to coat materials for drug release.
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Removal of Toxic Dichlorophenol from Water by Sorption with Chemically Activated Carbon of Almond Shells – A Green Approach

NAVEED AHSAN ,UMER SHAFIQUE ,NADIA JAMIL ,MUNAWAR ALI MUNAWAR ,JAMIL ANWAR ,

Chlorophenols (CP) represents a group of organic compounds having substituted chlorines attached to phenol ring. These trace organic pollutants represent a major environmental concern, because of toxicity, non-biodegradability, carcinogenic and stubborn properties. The adsorption of 2, 4-dichlorophenol (DCP) by chemically activated carbon of almond shells (CAC-AS) has been studied in the batch setup. Operational parameters like adsorbent dose, pH, and shaking speed were investigated. Langmuir and Freundlich isotherms were employed to calculate adsorption capacity and other sorption features of CAC-AS. The maximum amount of DCP adsorbed was 24.3 mg per gram of activated carbon derived from almond shells. Optimum conditions for DCP uptake were 2.5g adsorbent dose, pH 5 and agitation speed of 200 rpm whereas the concentration of DCP solution was 25 mg/L (50 mL). Results corroborated that almond shells pretreated chemically, can be an excellent low cost adsorbents for removal of DCP from contaminated water.
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Effect of Fluorozis on the Erythrocyte Antioxidant Enzyme Activity Levels

SULEYMAN KALELI ,MEHMET AKDOGAN ,DUDU YILMAZ ,IBRAHIM KILIC ,MUSTAFA YONTEM ,

While the flourine level of (drinking) water was higher than normal ranges in the center of Isparta region before 1995 year, this problematic situation is solved in later years. (However) the individuals who are staying in Yenice district are still expose to high levels of fluorine because of the usage of Andik spring water (3.8 mg/L flour level) as drinking water. In this study we aimed to investigate the harmful effect of floride on human erythrocytes via antioxidant defence system and lipid peroxidation. Therefore, we studied the activities of erythrocyte antioxidant enzymes such as Superoxide Dismutase (SOD), Glutathione Peroxidase (GSH-Px) and Catalase (CAT), and the level of erythrocyte Glutathione (GSH), thiobarbituric acid reactive substance (TBARS) and the level of urine floride in high floride exposed people (childen, adult and elderly). The activities of SOD, GSH-Px and CAT and the level of GSH, TBARS and urine floride were higher in 3.8 mg/L floride exposed children (Group II) than 0.8 mg/L floride exposed control children (Group I) (p<0.001, p<0.001, p<0.01, p<0.001, p<0.001, p<0.001, respectively) The activities of SOD and CAT and the level of TBARS and urine floride were higher in 3.8 mg/L floride exposed adult (Group IV) than 0.8 mg/L floride exposed control adult (Group III) (p<0.001).  On the other hand, no significant changes were observed in the activity of GSH-Px  and the level of GSH in Group IV and Group III (p>0.05). The activities of SOD, GSH-Px and CAT were lower and  the levels of  TBARS and urine floride were higher in 3.8 mg/L floride exposed elderly people (Group VI) than 0.8 mg/L floride exposed control elderly people (Group V) (p<0.001). However, the decrease in GSH level was not significant (p>0.05). As a result we thought that increased SOD, GSH-Px and CAT activities in floride exposed children and adult people, decreased activities of these enzymes in floride exposed elderly people, and increased TBARS in all groups may indicate floride caused oxidative damage in erythrocytes.
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Synthesis and Physiochemical Investigation of Cobalt (II) and Nickel (II) Complexes of 1-2-[(Z)-2-(3-acetyl-4-hydroxyphenyl)-1-diazenyl]phenyl-1-ethanone

ABDELSALAM MAATOQ HAMIL ,MAREI MAILOUD EL-AJAILY ,

Two divalent metal complexes of Co(II) and Ni(II) ions with the 1-2-[(Z)-2-(3-acetyl-4- hydroxyphenyl)-1-diazenyl]phenyl-1-ethanone were synthesized and investigated by several tools  such as; CHN elemental analyses, molar conductance measurements , infrared and electronic spectra. The CHN elemental analysis data showed the formation of 2:1[M:L] ratio of the formula of [M2L (Cl)2 (H2O)6], where, M represents Co(II) or Ni(II) ions. The molar conductance measurements indicate the existence of non-electrolytic nature. The infrared spectral data displayed the proper behavior of  the synthesized 1-2-[(Z)-2-(3-acetyl-4-hydroxyphenyl)-1-diazenyl]phenyl-1-ethanone  towards the metal ions. The electronic spectral data showed that both complexes have an octahedral geometry.
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Potentiometric Titrations of Para and Nitro Substituted Aromatic Acids and their Mixtures in Methylethylketone

CEMAL ÖZEROĞLU ,MESUT KARAHAN ,

In this study, it was the purpose to examine the potentiometric titrations of para and nitro substituted aromatic acids in methylethylketone (MEK) as a non-aqueous solvent. Good analytical results were obtained in determining the amount of each acid and the amounts of acids in their ternary mixtures by using 0.0964 N tetrabuthylammoniumhydroxyde (TBAH) as a standard titrant. Methylethylketone (MEK) which is a good solvent for many organic compounds and has a convenient liquid range of -86 to 80 °C was used for titration of the para and nitro substituted aromatic acids. A linear relationship has been found between pKa values of the para and nitro substituted aromatic acids in water and the half neutralization potential (HNP) values determined by potentiometric titration curves of the same acids in MEK.
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Comparing Heavy Metals Accumulation Potential in Natural Vegetation and Soil Adjoining Wastewater Canal

MUHAMMAD IRSHAD ,NAUREEN AURANGZEB ,FURRUKH HUSSAIN ,QAISAR MAHMOOD ,

Heavy metal (HM) pollution of waters, soils and vegetation is a major ecological problem that needs to be investigated.  The present study involved the collection of soil samples and natural vegetations (Tribilas terristris, Lepia nodiflora, Amaranthus viridis, Heliotropium euoropeum, Coronopis didymus, Cynodon ductylon, Chenopodium murale and Eclipta alba) from the vicinity of wastewater canal and subsequent analysis for their HM concentrations. Results showed that HM concentrations varied within the species of vegetation and type of metal analyzed. The order of vegetation for metal concentrations was A. viridis > E.  alba > H. euoropeum > L. nodiflora > C. murale > C. didymus > C. ductylon > T. terristris.  Metals prevailed in plants in the decreasing order of Fe > Mn > Zn > Pb > Cr > Cu > Cd, irrespective of the vegetation. Metal prevalence in soils was in the order of Fe > Mn > Cd > Cr > Pb > Zn > Cu. Samples near canal were found with higher level of Mn, Pb and Zn as compared to soil away from canal water. Distant sampling gave higher accumulation of Cd, Cr, Cu and Fe as compared to the soil nearby wastewater. The analyzed species of HM in the soils and plants may indicate the variability of their composition in wastewater.
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Synthesis of High-Activity TiO2/WO3 Photocatalyst via Environmentally Friendly and Microwave Assisted Hydrothermal Process

YUAN GAO ,JUNGANG YIN ,GUANGJUAN REN ,HUITAO LIU ,AN XING ,

This work focused on the synthesis of high-activity TiO2/WO3 photocatalysts through an environmentally friendly and novel process. A high energy-efficient microwave assisted hydrothermal method was employed to prepare TiO2/WO3 from TiCl4 and Na2WO4 without using any organic species. The properties of the synthesized catalysts were characterized by XRD, TEM and BET. The size of the obtained TiO2/WO3 photocatalyst was about 10 nm with high specific surface areas larger than 150 m2/g. Compared with pure TiO2, the TiO2/WO3 nanoparticles exhibited better photocatalytic activity for the degradation of Rhodamine B under visible light irradiation.
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