VOLUME 35, NO1, FEB 2013
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Comparative Sorptive Removal of Direct Red-28 dye

RABIA REHMAN, AADIL ABBAS, SHAHZAD MURTAZA, TARIQ MAHMUD

Use of agro-waste material for adsorption is studied now-a-days extensively. But the main problem is their low adsorption capacity as compared to synthetic adsorbents. So, in the following study, adsorption capacity of Okra stem powder had been investigated after chemical modification by acid, base and 2-propanol for adsorption of Direct Red-28 dye from water in batch mode. The results indicated that as compared to untreated biosorbent , acid treated and 2-propanol treated biosorbents had more adsorption capacity, i.e.: 1.86, 2.74 and 6.61 mg.g-1 correspondingly, whereas base treated biosorbent had lower adsorption capacity for this anionic dye, i.e.1.02 mg.g-1.
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Chemical studies of Launaea nudicaulis Hook f. ext

FARRUKH MANSOOR AND ITRAT ANIS

An activity guide isolation of Launaea nudicaulis Hook f, medicinal plant of Indo-Pak region has shown antioxidant potentials via its polar solvent soluble fractions while urease inhibition studies (in vitro) indicated compound 9 as a potent urease inhibitor. Eight compounds have also been isolated for the first time from Launaea nudicaulis Hook f., namely, Scopoletin 1, lupeol 2, β-amyrin 3, β-sitosterol 3-O-β-D-glucopyranoside 4, stigmasterol 3-O-β-D-glucopyranoside 5, 6-hydroxy flavone 6, 7-methoxy flavone 7 and 4-hydroxy-3,5-dimethoxy benzaldehyde 8, respectively. Their structures were elucidated by EI-MS, FABMS, 1H-NMR spectroscopic data.
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Enhancing Post Harvest Storage Life of Peach Fruit

MUHAMMAD SOHAIL, SHAHID AKBAR KHALIL, SHAMSUR REHMAN AFRIDI, REHMAN ULLAH KHAN, TAUFIQ AHMAD AND FARMAN ULLAH

The present study was conducted to enhance the post harvest storage life of peach fruits using calcium chloride treatments. CaCl2 solution at 1 % (T1), 2 % (T2) and 3 % (T3) were prepared and the fruits were dipped for five minutes, while (To) was left with out calcium chloride treatment as control. The fruits were packed in corrugated soft board cartons and stored at ambient temperature (35oC + 2) for a total period of 15 days. The physicochemical analysis such as weight loss, fruit firmness, total soluble solids (TSS), decay index, titratable acidity, ascorbic acid content and overall sensory acceptability were determined at an interval of three days up to the successful completion of the study. A significant decrease was observed in fruit firmness (1.8-0.3 kg), % acidity (0.950-0.538), ascorbic acid content (7.06-4.67 mg/100g) and overall sensory acceptability (8.4-2.3), while a significant increase was observed in TSS (8.2-11.9obrix), decay index (0-72.64 %) and % weight loss (0-11.3) during storage. Results showed that one and two percent calcium chloride treated fruits have little improvement while fruits treated with 3 % calcium chloride were found to be most acceptable as per physico-chemical analyses and over all sensory acceptability result.
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Mixture Pseudo-Chromatographic Separation by Matri

WEI LIU AND JIAN-JI WU

Pseudo-separation for phenylalanine (Phe), ibuprofen (Ibu), capsaicin (Cap) and norfloxacin (Nor) were studied by sodium dodecyl sulfate (SDS) or hydroxypropyl-β-cyclodextrin (HPβCD) assisted diffusion ordered spectroscopy (DOSY). Stokes-Einstein equation shows a linear relationship between the logarithms of apparent diffusion coefficients and logarithms of molecular weight (Mw). However, with matrix added, block factors became the important factors than molecular weight. Pseudo-separation was improved by SDS or HPβCD assist. Research showed different separation mechanism for SDS and HPβCD-assisted DOSY. The former used different lipo-hydro partition coefficient, and the latter used complexing mechanism.
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SEM-EDX and FTIR Studies of Chlorinated Rubber Coa

HUMAIRA BANO, MAZHER ISLAM KHAN AND SYED ARIF KAZMI

Anticorrosive performance of chlorinated rubber coating has been investigated by visual examination, Scanning electron microscopy (SEM)/Energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy. After surface preparation, commercially available coating system based on chlorinated rubber (primer)/chlorinated rubber (topcoat) formulation was applied on mild steel test panels (10cm x 15cm sizes). Prepared coated panels were exposed at marine, industrial and urban test sites located in Karachi, Pakistan according to ISO 8565 norm. Accelerated testing was performed by using a salt spray chamber (ASTM B117 norm). Accelerated weathering methods are the methods in which the factors responsible for the degradation of coatings are artificially intensified in order to achieve the rapid degradation of coatings. Visual examination of blistering and rusting as well as SEM micrographs indicated a more severe degradation of the coating surface characteristics at natural exposure testing sites (particularly at marine test site) than for accelerated (salt spray) testing. EDX determination of the Oxygen/Carbon (O/C) ratios also indicated increased degradation at natural test sites compared to the accelerated (salt spray) testing. Photooxidation of the binder results in the formation of carbonyl compounds as revealed by FTIR spectroscopy which also indicated dehydrochlorination.
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Comparative Performance Evaluation of Conventional

ASSAD FAROOQ AND MUHAMMAD AZEEM ASHRAF

Conventional bleaching process is an important and quality influencing process for textile wet processors. However, the process requires high energy consumption, and is slow and time consuming. In the present research work, cotton woven fabric was bleached with different bleaching agents using conventional and ultrasonic assisted techniques. After bleaching whiteness index, weight loss and tensile strength of samples were measured and compared statistically. The results showed that ultrasonic energy intensifies the diffusion of chemicals and increases the production of hydroxyl radicals which catalyze the bleaching process. Ultrasonic assisted bleaching proved to be a novel technique that can produce better results than conventional bleaching process even at low temperature and in less time.
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Improving Pitting Corrosion Resistance of Aluminum

PETER JOHN, ISLAM ULLAH KHAN, SHAHID TUFAIL SHEIKH, NAEEM GULZAR AND AZIZ-UR- REHMAN

Anodizing of aluminum was studied in sulphuric/citric/boric acid electrolyte system to improve pitting corrosion resistance. Maximum oxide film thickness was obtained using 5% sulphuric acid, 3% citric acid and 0.5% boric acid electrolyte composition. The corrosion resistance of aluminum sample was determined to find the effectiveness of oxide coating by potentiodynamic polarization test. The surface morphology of aluminum samples was investigated using scanning electron microscope (SEM) before and after corrosion test. It was found that the coated aluminum sample obtained by anodizing in sulphuric/citric/boric acid electrolyte system exhibited better pitting corrosion resistance with no significant difference in surface morphology.
Pages(72)
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Analytical Role of Sodium Dodecyl Sulphate in ICP-

SHAHID AMIN, SYED SAKHAWAT SHAH AND KHURSHID ANWAR

Effect of Sodium Dodecyl Sulphate (SDS) on sample transport efficiency, nebulisation and overall contribution in analysis using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for different analytes has been studied. The objective of this study was to investigate the effect of surfactant on the quality of aerosols results in enhancement or depression of the final analyte signals The SDS is anionic in nature, has been added to set of standards containing Cr, Fe, Co, Ni, Cu, Cd and Pb in the presence of 0.01% - 2.0% HNO3. Typical property of surfactants i.e. lowering of surface tension has been exploited to modify the analytical procedures for analysis through ICP-AES. Determinations were carried out using 5 ppm analytes under a set of conditions i.e. below Critical Micelle Concentration (CMC) at CMC and above CMC of the surfactant used. All glass Meinhard pneumatic nebuliser was used for the nebulisation processes. The results have been explained on the basis of a mild action of the surfactants to modify the plasma analytical conditions due to the change in the overall physical parameters.
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Preparation, Characterization and Antibacterial Ac

RANDA SAAD EL-ZWEAY, MAREI MILOUD EL-AJAILY, SALHA FARAJ BEN-GWEIRIF AND ABDSALAMALI MAIHUB

The Mn(II), Fe(III), Co(II) and Cu(II) mixed ligand chelates derived from catechol (L1) and 2-aminobenzothiazole (L2) have been prepared and characterized by different techniques, in particular; CHNS elemental analysis, molar conductivity, magnetic moments, infrared and electronic spectra. The CHNS elemental analysis data showed the formation of 1:1:1 and 2:1:1 [M:L1:L2] chelates. The molar conductance measurements revealed a non-electrolytic nature. The magnetic moment measurements exhibited a paramagnetic phenomenon. The infrared spectral data showed the coordination sites that are via –OH, C=N and NH2 groups of the mentioned ligands. The electronic spectra exhibited the expected geometrical structures for the chelates. The prepared Cu(II) and Fe(III) chelates were assayed for antibacterial activity against some human pathogenic bacteria: Staphylococcus aureus, Escherichia coli and klebsilla pneumoniae using the hole diffusion method and placing the chelates on surface at nutrient agar. No effects were recorded. This result suggests the absence of active components or due to the insensitivity of bacteria we assayed.
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Phosphoric Acid Manufacturing Through Hydrochloric Acid Route by Solvent Extraction

MUHAMMAD ASHRAF KHAN, MUHAMMAD ARIF, IMTIAZ-UD-DIN, KHALID MOHAMMED KHAN AND NIDA AMBREEN

The production of high grade phosphate fertilizers requires a good quality phosphoric acid since it is an important raw material for these industries. The present report describes an efficient and economical route for manufacturing phosphoric acid by treating rock phosphate with commercial hydrochloric acid followed by its separation from the crude mixture by solvent extraction using amyl alcohol as solvent. The acid, obtained by this method, is of high quality and could be upgraded up to density of 1.5 g/mL at 25 °C.
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