VOLUME 38, NO2, APR-2016
123
 
Synthesis and Properties of a New Multifunctional Gemini Anionic Surfactant

Hongjiang Yu, Deng Qiang, Ning Yang, Chen Shijun, Zhao Kang and Chen Gang

A new Gimini cationic surfactant (BHAC) was synthesized using succinic acid, epichlorohydrin and N,N-dimethyldodecylamine as raw reactants. The reaction conditions of in the quaterisation reaction were investigated including the temperature, reaction time, and molar ratio. The surface properties, including critical micelle concentration (CMC), foamability and foam stability, were evaluated. The results showed that the minimum surface tension was 28.1 mN/m at the concentration of 1×10-3 mol/L, and the foamability and foam stability measurement are consistent with those of CMC.
Pages(186)
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Effect of Superfine Grinding on Physicochemical Properties of Apple Pomace

Xinhong Liang, Junliang Sun and Hanjun Ma

The effect of superfine grinding on the physicochemical properties of apple pomace was investigated in this study. The optimal ultrafine powder could be obtained under the conditions of motor speed 450 rpm and fan speed 300 rpm, whose particle size, water-solubility index, angle of repose, total phenolic content and total sugar content were 10.23±0.42 μm, 33.65±0.91%, 39.36±1.59°, 12.62±0.34 mg GAE/g and 136.14±3.1 mg/g, respectively. Compared with the traditional powder, the significant increase of water-solubility, total phenolic content and total sugar content could be found while the decrease of angle of repose could be observed. It could be concluded that the bioavailability of functional and nutritional ingredients of apple pomace could be significantly improved by superfine grinding
Pages(192)
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Impact of Lipophilic Surfactant on the Rheology and Stability of Water-in-Soybean Oil Emulsion

Shahid Iqbal, Musa Kaleem Baloch, Gulzar Hameed and Rubina Naz

In order to get long time stability in Water-in- Soybean oil emulsion the impact of self- structuring lipid, polyglycerol polyricinoleate (PGPR) has been investigated. The rheological and microstructural techniques were employed to characterize the stability and flow behavior of the material. Emulsions were prepared from 10- 40 wt. % water having 2-8 wt. % Polyglycerol polyricinoleate in phosphate buffer (pH 7, NaCl 100mM). It has been observed that an increase in water contents led to decrease in stability of emulsion while the impact of Polyglycerol polyricinoleate was other way round. The shear viscosity of the system was increased with the increase in water as well as polyglycerol polyricinoleate (PGPR) contents. The stated observations were also in accord with the optical micrographs and were helpful to explain the stability as well as the rheological results.
Pages(198)
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Optical Properties of Pure and Mixed Germanium and Silicon Quantum Dots

Shanawer Niaz, Aristides D. Zdetsis, Manzoor Ahmad Badar, Safdar Hussain, Imran Sadiq and Muhammad Aslam Khan

We study the optical properties of hydrogen passivated silicon, germanium and mixed Ge/Si core/shell quantum dots (QDs) using high accuracy Density Functional Theory (DFT) and time-dependent DFT (TDFT). We employ the hybrid DFT functional of Becke, Lee, Yang and Parr (B3LYP) in combination with good quality basis sets. As we have shown in our previous work, this combination is an accurate and computationally efficient way for such calculations. The mixed quantum dots, as would be expected, are more versatile and offer more possibilities for band gap engineering, with gap values (electronic and optical) between those of the corresponding Si and Ge dots. Our results support the quantum confinement theory for all three types of QDs.
Pages(207)
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Study on Electrochemical Fingerprints of Rhizoma Atractylodis Macrocephalae

Gen-Lian Bao, Jian Zhong Jin, Hang-Shi Xu and Zhong-Yang Wang

The electrochemical fingerprints of Rhizome atractylodis macrocephalae were studied by B–Z (Belousov-Zhabotinski) oscillation system of H+-Mn2+-CH3COCH3-BrO3-. The influences of temperature, stirring rate, hydrogen ion concentration, Rhizome atractylodis macrocephalae dosage, etc, to electrochemical fingerprints of Rhizoma atractylodis macrocephalae were investigated. The optimum conditions were established with total volume of 100 mL, temperature of 37℃, stirring rate of 400 rpm, hydrogen ion concentration of 1.980 mol•L-1, Rhizoma atractylodis macrocephalae dosage of 1.000 g, KBrO3 concentration of 0.05000 mol•L-1, MnSO4 concentration of 0.005600 mol•L-1 and CH3COCH3 of 1.00 mL by comparing difference of the electrochemical fingerprints of Rhizoma atractylodis macrocephalae from two choosen regions. The results indicated that the electrochemical fingerprints of Rhizoma atractylodis macrocephalae from different origins showed significantly different characteristics, so the electrochemical fingerprint is a simple method to identify the origins and variety of Rhizoma atractylodis macrocephalae.
Pages(214)
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Corrosion Inhibition Effect of N, N’-diphenylthiourea on the Electrochemical Characteristics of Mild steel in Dilute Acidic Environments

Roland Tolulope Loto, Cleophas Akintoye Loto, Abimbola Patricia Popoola and William Kupolati

The electrochemical corrosion behaviour of n, n’-diphenylthiourea on the surface properties mild steel in attenuated sulphuric and hydrochloric acids (3M concentration) contaminated with 3.5% recrystalized sodium chloride at ambient temperatures was examined through weight loss analysis, open circuit potential monitoring and potentiodynamic polarization. The surface morphology of the samples was analyzed with scanning electron microscopy and x-ray diffractometry. Statistical analysis of the results was done with aid of ANOVA software to assess their statistical relevance. Results show the thiourea derivative performed more excellently in sulphuric than hydrochloric acid based on inhibition efficiency values. Observations from SEM/XRD image and data further confirm the results of experimental data. Statistical derivations reveal the overwhelming influence of exposure time on inhibition performance compared to concentration of the organic compound.
Pages(222)
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Synthesis and Characterization of Three-Phase Polymer-Graphene Oxide-Ceramic Composites

Muhammad Saleem Khan, Mohammad Sohail, Noor Saeed and Ayesha Afridi

In this study, novel three-phase hybrid (inorganic-organic) composite comprising Fe0.01La0.01Al0.5Zn0.98O ceramic particles (FLAZPs), conducting polymer polyaniline (PANI) and grapheme oxide (GO) was synthesized. The ceramic particles were produced by sol-gel technique. For the homogeneous dispersion of FLAZPs particles in the PANI matrix, in-situ free-radical polymerization of aniline (PANI precursor) was performed. FLAZPs distributed in the matrix during the polymerization process. GO was synthesized via modified Hummer’s method which was then blended with two-phase composite using simple one-pot blending technique. The prepared materials were subjected to FT-IR, TGA, XRD and SEM to analyze their physical properties. FT-IR showed the successful complexation of the materials with one another. XRD confirmed the crystalline nature and phase distribution in the composites. FLAZPs enhanced the thermal stability of PANI and GO in the composites. SEM showed that ceramic particles are in the range from micro to nanometer and are well dispersed in the PANI matrix in two-phase composite. Furthermore, GO prevented the agglomeration of particles while interacting with PANI in the three-phase composite. Extensive dielectric studies were carried out which showed that PANI and GO have about the same additional effect on various dielectric properties of FLAZPs. The AC conductivity (σ = 7.79 x 10-1 Ω-1cm-1) achieved by two-phase and three-phase composites is much higher in comparison to pure FLAZPs (σ = 3.17 x 10-1 Ω-1cm-1).
Pages(234)
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Biological and Docking Studies of Sulfonamide Derivatives of 4-Aminophenazone

Muhammad Shoaib Akhtar, Asmara Ismail, Shahzad Murtaza, Muhammad Nawaz Tahir, Saima Shamim and Usman Ali Rana

Sulfonamide derivatives of 4-aminophenazone (4APZ) were synthesized and accordingly characterized by spectroscopic techniques. These newly synthesized compounds were examined for their biological activities such as enzyme inhibition, analgesic, antibacterial, antioxidant and DNA interaction. A direct correlation between enzyme inhibition activity and concentration of the compounds was observed both by experimental and molecular docking studies. Analgesic activity of the compounds was investigated by formalin-induced paw licking (FIPL), acetic acid-induced writhing (AIW) and heat conduction methods in mice. Membrane stabilization effect was determined by hypotonicity-induced hemolysis. Bacterial strains, S. aureus, S. epidermidis, B. subtilis, E. coli, P. aeruginosa, S. mutans and A. odontolyticus were used for investigating the antibacterial potential of the compounds. Antioxidant potential was investigated by Ferric Reducing Antioxidant Power assay (FRAP) and DPPH free radical scavenging method. DNA interaction studies of the synthesized compounds showed weak interaction. Hyperchromic effect was observed along the series and large positive K values were obtained for most of the compounds.
Pages(242)
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5-Nitroimidazole Derivatives and their Antimicrobial Activity

Khalid Mohammed Khan, Uzma Salar, Saima Tauseef, Ghulam Abbas Miana, Sahar Yousuf, Farzana Naz, Muhammad Taha, Saifullah Khan and Shahnaz Perveen

5-Nitroimidazole derivatives 2-8 were synthesized from secnidazole. The syntheses were accomplished in two steps which start from the oxidation of secnidazole to the secnidazolone 1. Secnidazolone 1 was converted into its hydrazone derivative 2-8 by treating with different substituted acid hydrazide. Compounds 2-8 were evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria, compounds 3 and 4 showed the significant activity against Staphylococcus epidermidis, however, compound 2 showed good inhibitions against Corynebacterium diphtheria when compared with the standard. Compound 3 showed good inhibitory potential against tested Gram-negative bacterial strains i.e. Enterobacter aerogene, Escherichia coli, Salmonella typhi, Salmonella paratyphi A, Shigella flexeneri and Vibrio choleriae. All synthetic derivatives were also tested against eight fungal stains, however, they were weekly active against Aspergillus flavus and Candida albican. The synthesized compounds were characterized by different spectroscopy techniques.
Pages(258)
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Evaluation of Chemical Composition and Biological Activities of Citrus pseudolimon and Citrus grandis Peel Essential Oils

Arfaa Sajid, Raja Adil Sarfraz, Muhammad Asif Hanif and Muhammad Shahid

Essential oils and their volatile constituents are used extensively to prevent and treat human diseases. In the past decades, worldwide demand for citrus essential oils has greatly increased. Citrus essential oils containing 85–99% volatile and 1–15% non-volatile components. Essential oils from Citrus pseudolimon and Citrus grandis peels were extracted through steam distillation and characterized by GC-MS. C. pseudolimon has thirty six and C. grandis has thirty three total components; limonene 47.07% and 71.48% was the major component in both oils respectively. Antioxidant activity was checked by 2, 2-diphenyl-1-picrylhydrazyl radical assay and β-carotene/linoleic acid bleaching test. Both oils have modest activity. The antimicrobial potential was assessed against different bacterial and fungus strains. C. pseudolimon oil possessed strong activity against all tested strains while C. grandis has moderate activity. The antitumor activity was evaluated by potato disc assay, C. pseudolimon showed 81.25% inhibition. Hence the essential oils could have a great potential in pharmaceutical industry.
Pages(266)
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