VOLUME 36, NO1, FEB-2014
123
 
Statistically Defining Optimal Conditions of Coagu

Mıthat Celebı, Zafer Omer Ozdemır, Emre Eroglu and Ibrahım Guney

Milk consist huge amount of largely water and different proteins. Kappa-kazein of these milk proteins can be coagulated by Mucor miehei rennet enzyme, is an aspartic protease which cleavege 105 (phenly alanine)-106 (methionine) peptide bond. It is commonly used clotting milk proteins for cheese production in dairy industry. The aim of this study to measure milk clotting times of skim milk by using Mucor Miehei rennet and determination of optimal conditions of milk clotting time by mathematical modelling. In this research, milk clotting times of skim milk were measured at different pHs (3.0, 4.0, 5.0, 6.0, 7.0, 8.0) and temperatures (20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75 oC). It was used statistical approach for defining best pH and temperature for milk clotting time of skim milk. Milk clotting activity was increase at acidic pHs and high temperatures.
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Evaluation of Antihistamine in Pure and in Dosage

Amjad Naseem and Amina Mumtaz

A charge transfer complex is formed when antihistaminic drug react with m-dinitrobenzene in basic medium. This complex is used for the determination of antihistamine (cyclizine hydrochloride) in pure and pharmaceutical formulations. The purple color complexes formed are quantified spectrophotomertrically at 540nm. Different statistic parameters like standard deviation, relative standard deviation, slope; intercept and coefficient of determination are calculated. The proposed method can be used successfully for routine analysis of cyclizine hydrochloride in pure and in dosage forms.
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Chitosan-Based Polymer Blends: Current Status and

Esam Abdulkader El-Hefian, Mohamed Mahmoud Nasef and Abdul Hamid Yahaya

This paper reviews the latest developments in chitosan-based blends and their potential applications in various fields. Various blends together with other derivatives, such as composites and graft copolymers, have been developed to overcome chitosan’s disadvantages, including poor mechanical properties and to improve its functionality towards specific applications. The progress made in blending chitosan with synthetic and natural polymers is presented. The versatility and unique characteristics, such as hydrophilicity, film-forming ability, biodegradability, biocompatibility, antibacterial activity and non-toxicity of chitosan has contributed to the successful development of various blends for medical, pharmaceutical, agricultural and environmental applications.
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An Optimization Study on Removal of Zn2+ from Aque

Enes Şayan

Nowadays, ultrasound has gained importance in a wide variety of industrial fields especially in wastewater and sewage treatment. Ultrasound exhibits several beneficial effects in solid–liquid systems by means of the cavitations phenomenon by causing the formation of many microcracks on the solid surface; thus, it increases the surface area between the reactants and cleans solid reactant or catalyst particle surfaces. In this study, activated carbon adsorbent for removing heavy metal cations such as Zn2+ from aqueous solutions has been prepared. For this purpose, KOH solution was impregnated into hazelnut shells under ultrasonic irradiation. After filtration, hazelnut shells have been carbonized under inert N2 atmosphere. The experiments were planned by statistical design methods. Finally, activated carbons were characterized by the evolution of their zinc adsorption capacity. Optimum preparation conditions were obtained by using constrained optimization program by means of the Matlab computer software. Activated carbon with the maximum adsorption capacity was further characterized by using scanning electron microscopy. The alkaline impregnation into hazelnut shells under ultrasonic irradiation was found to be beneficial for preparation of activated carbon for use as adsorbents to remove Zn2+ from aqueous solutions.
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Improved Photocatalytic Activity of TiO2 Coupling

Maria Siddique, Romana Khan, Ather Farooq Khan and Robina Farooq

The degradation of Reactive Blue 19 (RB 19) using photolysis, photocatalysis and sonophotocatalysis in aqueous solutions was investigated. Emphasis was given on the effects of different operating conditions viz. catalyst concentration, pH, initial dye concentration, ultrasonic power and reaction time) on RB 19 degradation. The extent of photocatalytic and sonophotocatalytic degradation was increased by decreasing pH, initial dye concentration and increasing catalysts loading and ultrasonic power. Ultrasound combined with photocatalysis was found efficient than the respective individual processes due to the enhanced formation of reactive hydroxyl radicals as well as the possible ultrasound-induced increase of the active surface area of the catalyst. The sonophotocatalytic efficiency was increased in acidic conditions as compare to individual processes at same experimental conditions (100 mg L-1 of dye concentration, 300 mg L-1 of TiO2 concentration, 240 W ultrasonic power and at pH 4). The kinetic study of RB 19 degradation under different experimental conditions apparently followed first order reaction. The intermediates and end products formed during the degradation were identified using gas chromatography/mass spectrometry (GC/MS) and a possible degradation pathway of RB 19 was proposed.
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Counting Statistics of Uranium Determination by X-

Riaz Qadeer and Nasir Khalid

The procedure has been explained to evaluate the equipment performance by repeated measurements of energy dispersive X-ray fluorescence signal of 4.201  104 mol L1 uranium solution in 3 mol L1 of HNO3. Standard statistical models were applied to the data. The Poisson distribution function [F(X)P] and Normal distribution function [F(X)N] were found to be 1.0197 and 1.0049 respectively, which are quite near to the ideal value of unity. Linearity range for uranium determination by XRF was found to be up to 1.47  102 mol L1 of uranium, with regression coefficient “R2” of 0.998 under the optimized instrumental parameters.
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Effect of Wheat Straw Pretreatments and Glue Formu

Sidra Jabeen, Shahid Naveed, Sana Yousaf and Naveed Ramzan

In this paper, the effect of wheat straw (WS) pretreatments and glue formulations on mechanical (i.e. Compressive Strength (CS) and Impact Strength (IS)) and water resistance properties (i.e. Thickness Swelling (TS) and water absorption (WA)) of particle board have been investigated and the results have been compared with conventional wooden particleboard . Wheat straw was treated with steam available at 110°C and 20 psig, for the retention time of 5, 10 and 15 min. The solution of 10% HCl was also used for removing the lignin. Particleboard was prepared by bonding treated WS with four types of glue recipes of synthetic and natural binders like urea formaldehyde (UF), polyvinyl acetate (PVA), corn flour (CF) and wheat flour (WF). The particle board was formed at the hydraulic pressure and temperature of 2800 psig and 80°C respectively. It was observed that WS particleboard has low mechanical strength and high water resistance in comparison with conventional board. The particle board prepared with HCl cured wheat straw and glue having high urea formaldehyde and corn flour has higher CS and IS as well as low TS and WA. It may be concluded that wheat straw is a good substitute of wood for particle board while using HCl as a modifying chemical and strong binders like urea formaldehyde and corn flour.
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Synthesis and Characterization of 1,2-bis[4-(pent-

Muhammad Shabbir, Zareen Akhter, Asghari Gul and Michael Bolte

A novel crystalline enaminoketone ligand was synthesized by reacting 1, 2-di (4-aminophenyloxy) ethylene with acetyl acetone. After that it was complexed with different metal acetates to prepare chromium Cr (II), cobalt Co (II), copper Cu (II) and zinc Zn (II) complexes. Elemental analysis, magnetic susceptibility measurements, thermogravimetric analysis, x-rays crystallographic studies, UV-visible spectroscopy were carried out for structural elucidation and property exploration. The ligand exhibited quardidentate structure with two N-donor and two O-donor atoms with central methylene bridge in the gauche conformation which was stabilized by two intramolecular N-H--O hydrogen bonds The dihedral angle between the two aromatic rings was 45.1o. All complexes were thermally stable and exhibit square planar or tetrahedral geometries.
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Determination of Bisphenol A and Bisphenol AF in V

Zhigang Tai, Yingtang Li, Mousheng Liu, Xujia Hu, Yaling Yang and Benkui Qin

This paper describes a sensitive and simple method for the determination of bisphenol A (BPA) and bisphenol AF (BPAF) in vinegar samples using two-component mixed ionic liquid dispersive liquid-phase microextraction coupled with high performance liquid chromatography. In this work, BPA and BPAF were selected as the model analytes, and two-component mixed ionic liquid included 1-butyl-3-methylimidazolium hexafluorophosphate ([C4Mim]PF6) and 1-hexyl-3-methyl-imidazolium hexafluorophosphate ([C6Mim]PF6) was used as the extraction solvent for the first time here. Parameters that affect the extraction efficiency were investigated. Under the optimum conditions, good linear relationships were discovered in the range of 1.0-100 μg/L for BPA and 2.0-150 μg/L for BPAF, respectively. Detection limits of proposed method based on the signal-to-noise ratio (S/N=3) were in the range of 0.15-0.38 μg/L. The efficiencies of proposed method have also been demonstrated with spiked real vinegar samples. The result show this method/ procedure to be a more efficient approach for the determination of BPA and BPAF in real vinegar, presenting average recovery rate of 89.3-112 % and precision values of 0.9-13.5% (RSDs, n = 6). In comparison with traditional solid phase extraction procedures this method results in lower solvent consumption, low pollution levels, and faster sample preparation.
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Effects of Emulsifier on Monolayer Structure and E

Lei Li, Jiaping Liu, Qian Tian and Zhiyong Zhang

In present paper, five non-ionic emulsifiers with different hydrophobic and hydrophilic groups were synthesized to discuss effects of emulsifier on monolayer structure and evaporation resistance. After testing the evaporation resistance, the dispersion rate and stability of the monolayers prepared from different emulsifiers were characterized. It could be inferred that compared with dispersion rate, stability seemed to be the more important factor which might control the monolayer performance, and emulsifier with small volume and strong interaction force between chains might be beneficial to decrease water evaporation.
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