VOLUME 35, NO3, JUN 2013
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Optimization of Easy-Care Finishing of Cotton/Polyester Blend Fabric

MUHAMMAD SALEEMUDDIN, SYED TARIQ ALI, MUHAMMAD KASHIF PERVEZ, MUHAMMAD JAVAID MUGHAL, MUNAWWER RASHEED

The objective of the given study was to obtain eco-friendly finishes and optimized application parameters of easy-care finishing. Easy-care finishing of cotton/polyester blend fabric was done at different pH values and resin concentrations using three different types of cross-linking finishing resins: modified dihydroxyethylene urea (I), modified dimethyloldihydroxyethylene urea (II), and modified N-methyloldihydroxyethylene urea (III). Optimum mechanical properties (wrinkle recovery angle WRA; 252 (W+Fo) and tensile strength TS; 2143 N) were observed at 30 g/l of resin I and 5.0 pH. At these conditions resin I showed lowest free formaldehyde content (3.07 mg/kg). Formaldehyde (HCHO) was extracted, derivatized, and estimated as DNPH-formaldehyde using HPLC through a C18 column. No appreciable difference in easy-care properties were observed when cotton/polyester blend fabric was finished, in optimized conditions, with resins II and III, except slightly increased HCHO.
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Determination of Kinetic Constants from Tests of Reducibility and their Application for Modelling in Metallurgy

PAVLINA PUSTEJOVSKA, SIMONA JURSOVA AND BROZOVA SILVIE

The paper analyses details for renewal of the research in blast furnace process within Research Centre ENET at VŠB – Technical University of Ostrava. A newly established laboratory for reducibility testing is an impuls to overcome the former limits and renew a research in its coherence after years. The paper deals with the possibilities of optimization of blast furnace operation. In the introduction, it sums up different approaches how to model blast furnace operation. It discusses the variety of optimal operation for different kinds of iron making technologies. It evaluates reduction course and reducing gas consumption in the stack of reduction aggregate. In the experimental, it creates kinetics model of blast furnace operating using Matlab mathematical library. It determines kinetic and heat limits of carbon consumption for different process conditions.
Pages(565)
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Simple Growth and Characterization of α-Sb2O4: Evaluation of their Photo-catalytic and Chemical Sensing Applications

ASLAM JAMAL, MOHAMMED MUZIBUR RAHMAN, SHER BAHADAR KHAN, MOHAMMED MARGUB ABDULLAH, MOHD FAISAL, ABDULLAH MUHAMMAD ASIRI, AFTAB ASLAM PARWAZ KHAN, KALSOOM AKHTAR

A comprehensive study on the synthesis, characterization and application of antimony oxide (α-Sb2O4) has been reported in this paper. Antimony oxide (α-Sb2O4) is successfully synthesized by hydrothermal method using antimony chloride and urea as a reducing materials. The morphology of the nanomaterial is investigated by field emission scanning electron microscopy (FE-SEM). Sheet like morphology of α-Sb2O4 ranging from 0.2 µm to 3.0 µm are found in the FE-SEM images. The detailed structural characterizations are performed by X-ray diffraction (XRD), Fourier transform infrared spectrophotometer (FT-IR), and Raman spectrophotometer respectively. It has been confirmed that the synthesized materials are well-crystalline and pure antimony oxide (α-Sb2O4). Optical properties are studied using UV-VIS spectrophotometer, where the direct band-gap of α-Sb2O4 is calculated to be 3.26 eV. The photo-catalytic degradation and chemical sensing applications are successfully checked by simple and reliable UV/vis. spectroscopy and I-V methods respectively.
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Removal of Paraquat and Linuron from Water by Continuous Flow Adsorption/ Ultrafiltration Membrane Processes

MUHAMMAD ZAHOOR

The magnetic activated carbon (MAC) was prepared, characterized and compared with powdered activated carbon (PAC) for its adsorptive parameters. Both adsorbents were then used in combination ultrafiltration (UF) membrane as pretreatment for the removal of paraquat and linuron from water. The comparison of membrane parameters like percent retention, permeate flux and backwash times for PAC/UF and MAC/UF hybrid processes showed that percent retention of paraquat and linuron was high for PAC due to its high surface area. However due to cake formation over membrane surface the decline permeate fluxes and long backwash times for PAC were observed. PAC also caused blackening of pipes and flow meter. MAC (an iron oxide and PAC composite) was removed from slurry through magnet thus no cake formation and secondary problems observed for PAC was not encountered. Also the backwash times were minimum for MAC/UF process.
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Kinetic and Hydrolytic Characterization of Newly Isolated Alkaline Lipase from Ganoderma lucidum using Canola oil Cake as Substrate

HAQ NAWAZ BHATTI AND FAIZA AMIN

In the present work, canola oil cake was used as a substrate for lipase production employing Ganoderma lucidum. The enzyme was isolated and partially purified using factional precipitation, ion exchange chromatography and gel filtration. The purified lipase had a specific activity of 33262 U/mg proteins with 2.26 % recovery. The pH and temperature optima of the lipase were 8.5 and 35 °C indicating its alkaline nature. The Michaelis-Menten parameters Km and Vmax were found to be 0.74 mM and 4762 µmol/min respectively. Energy of activation (Ea) for PNPP hydrolysis was found to be 12.80 kJ/mol. Thermostability studies of the enzyme at various temperatures showed that the enzyme denaturation followed pseudo-first-order kinetic. Effects of various metal ions, surfactants and organic solvents were investigated. The purified lipase had the highest hydrolytic activity for waste oil indicating its potential for wide application in oleochemical and biotechnological industries.
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In Vitro Assessment of Protection from Oxidative Stress by Various Fractions of Mazus pumilus

SAMMIA SHAHID, TAUHEDA RIAZ, MUHAMMAD ATHAR ABBASI, FARAH KHALID AND MUHAMMAD NADEEM ASGHAR

Bioactive compounds in food have been shown to maintain human health. Therefore the aim of this investigation was to evaluate antioxidant potential of an edible herb Mazus pumilus (Burm. f.) Steenis by spectrophotometric methods. Methanolic extract of the herb was obtained on Soxhlet apparatus, and sequentially fractionized with organic solvents of increasing polarity. The antioxidant potential of all these fractions was evaluated by four methods: 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, total antioxidant activity, Ferric reducing antioxidant power (FRAP) assay and ferric thiocyanate assay along with determination of their total phenolics. The results revealed that n-butanol fraction exhibited highest percent inhibition of DPPH radical as compared to other fractions. It showed 80.42±1.68 inhibition level, % of DPPH radical at a concentration of 60 µg ml-1. The IC50 value of this fraction was 28.79±1.35 µg ml-1, relative to ascorbic acid, having IC50 58.84±0.89 µg ml-1. It also showed highest total antioxidant activity (1.01±0.08) as well as highest FRAP value (626.83±0.39 TE / µM ml-1), highest total phenolic contents (88.30±1.09 GAE / mg g-1) and highest value of inhibition of lipid peroxidation (53.91±1.21 %) as compared to the other studied fractions. The results obtained from this study suggest that Mazus pumilus is a valuable herb, which due to the presence of larger quantities of antioxidant compounds inhibits the oxidative stress mechanism that lead to degenerative diseases.
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Treatment of Tanneries Waste Water by Ultrasound Assisted Electrolysis Process

ROBINA FAROOQ, MEHWISH DURRANI, ZAKI AHMED, MAZHAR AMJAD GILANI, QAISAR MAHMOOD, SALEEM FAROOQ SHAUKAT, NNAJI CHIOMA, MUHAMMAD FAROOQ AND ASIM YAQUOB

The leather industry is a major producer of wastewater and solid waste containing potential water and soil contaminants. Considering the large amount and variety of chemical agents used in skin processing, the wastewaters generated by tanneries are very complex. Therefore, the development of treatment methods for these effluents is extremely necessary. In this work the electrochemical treatment of a tannery wastewater by ultrasound assisted electrochemical process, using stainless steel and lead cathode and titanium anodes was studied. Effect of ultrasound irradiation at various ultrasonic intensities 0, 40, 60 and 80% on electrochemical removal of chromium was investigated. Experiments were conducted at two pH conditions of pH 3 and 9. Significant removal of chromium was found at pH 3 and it was also noticed that by increasing ultrasonic intensities, percentage removal of chromium and sulfate also increases. The optimum removal of chromium and sulfate ions was observed at 80% ultrasonic intensity. The technique of electrolysis assisted with ultrasonic waves can be further improved and can be the future waste water treatment process for industries.
Pages(599)
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Yttria-Modified Titania-CNTs Composite as an Electrochemical Biosensor for Lysine

SYED TAJAMMUL HUSSAIN, SYED MUSTANSAR ABBAS, MASSOD AHMAD KHAN BANGASH, MUNEEB UR REHMAN AND NISAR AHMAD

A composite of carbon nanotubes with yttrium modified titania particles (Y/TiO2-CNT) is synthesized and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and Fourier transform infrared spectroscopy (FTIR). The electrochemical behavior of amino group (Lysine) is investigated by cyclic voltammetery (CV). The response mechanism of the synthesized biosensor is proposed to be the combination of electrostatic and electrical interactions of CNTs with amino group. Excellent sensitivity, repeatability, stability, selectivity and recovery for the potentiometric determination of Lysine in the range of 5mM to 25mM concentrations are obtained.
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Utilization of Chemically Modified Citrus reticulata Peels for Biosorptive Removal of Acid Yellow-73 Dye from Water

RABIA REHMAN, MUHAMMAD SALMAN, TARIQ MAHMUD, FARAH KANWAL AND WAHEED-UZ-ZAMAN

Textile effluents contain several varieties of natural and synthetic dyes, which are non-biodegradable. Acid Yellow-73 is one of them. In this research work, adsorptive removal of this dye was investigated using chemically modified Citrus reticulata peels, in batch mode. It was noted that adsorption of dye on Citrus reticulata peels increased by increasing contact time and decreased in basic pH conditions. Langmuir and Freundlich isothermal models were followed by equilibrium data, but the first isotherm fitted the data better, showing that chemisorption occurred more as compared to physiosorption, showing maximum adsorption capacity 96.46 mg.g-1.L-1. The thermodynamic study showed that adsorption of Acid Yellow-73 on chemically modified Citrus reticulata peels was favorable in nature, following pseudo-second order kinetics.
Pages(611)
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DFT Studies of Halogen Bonding Abilities of Nitrobenzene with Halogens and Chlorofluorocarbons

KHURSHID AYUB AND TARIQ MAHMOOD

Chlorofluorocarbons are being used as coolants since the last more than fifty years, and their increasing concentration in atmosphere causes the ozone layer depletion, therefore to develop a sensor for detection of chlorofluorocarbons is environmentally significant. In this article the halogen bonding abilities of nitrobenzene along with halogens and different chlorofluorocarbons have been investigated theoretically at the B3LYP /6-31+G(d) method of DFT. All physical properties such as binding energy, equilibrium distance and dipole moment showed halogen bonding formation. Our investigations revealed that that electron rich nitrobenzene can be used as good sensor for the sensing of halogens (Cl2, Br2 and F2) and different chlorofluorocarbons (CFCs).
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