Journal of Applied Chemistry The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Theoretical Energy and Exergy Analyses of Proton Exchange Membrane Fuel Cell by Computer Simulation Sun, 18 Sep 2016 09:44:04 +0000 A mathematical model of a proton exchange membrane fuel cell (PEMFC) was developed to investigate the effects of operating parameters such as temperature, anode and cathode pressures, reactants flow rates, membrane thickness, and humidity on the performance of the modelled fuel cell. The developed model consisted of electrochemical, heat energy and exergy components which were later simulated using a computer programme. The simulated model for the voltage output of the cell showed good conformity to the experimental results sourced from the literature and revealed that the operating pressure, temperature, and flow rate of the reactants positively affect the performance and efficiencies (energy and exergy) of the cell. The results also indicated that high membrane thickness above 150 μm is unfavourable to both the fuel cell performance and the cell energy and exergy efficiencies. The simulated results obtained on the influence of membrane humidity on the cell performance indicated that membrane humidity positively favours both the performance and energy and exergy efficiencies of the cell. It can therefore be inferred that the performance of the PEMFC and energy and exergy efficiencies of the cell are greatly influenced by the operating pressure, temperature, membrane thickness, membrane humidity, and the flow rates of fuel and oxidant. I. D. Gimba, A. S. Abdulkareem, A. Jimoh, and A. S. Afolabi Copyright © 2016 I. D. Gimba et al. All rights reserved. Emerging Photovoltaics: Organic, Copper Zinc Tin Sulphide, and Perovskite-Based Solar Cells Tue, 06 Sep 2016 17:33:45 +0000 As the photovoltaics industry continues to grow rapidly, materials other than silicon are being explored. The aim is to develop technologies that use environmentally friendly, abundant materials, low-cost manufacturing processes without compromising on efficiencies and lifetimes. This paper discusses three of the emerging technologies, organic, copper zinc tin sulphide (CZTS), and perovskite-based solar cells, their advantages, and the possible challenges in making these technologies commercially available. Shraavya Rao, Ankita Morankar, Himani Verma, and Prerna Goswami Copyright © 2016 Shraavya Rao et al. All rights reserved. Preparation and Characterization of Chitosan-Humic Acid-Zerovalent Iron Nanocomposite for Nitrate Reduction in Water Mon, 05 Sep 2016 16:21:01 +0000 A new zerovalent iron chitosan-humic acid nanocomposite was prepared and tested for nitrate ion reduction in water. Humic acid was used for intramolecular cross-linking of the chitosan linear chains to increase the active sites on the chitosan biopolymer and then further used as a stabilizer to synthesize zerovalent iron nanoparticles by the reduction of iron (II) chloride with sodium borohydride. Characterization of the products was carried out using infrared spectroscopy, scanning electron microscope, energy dispersive X-ray, and X-ray diffractometer. Batch experiments were conducted for the reduction of nitrate in water using different concentrations of the products in different concentrations of nitrate ion and at different contact time. The adsorption equilibrium data for the nitrate solution gave a favorable adsorption according to the Langmuir equation. Varying the nanocomposite-to-nitrate ion ratio generally led to faster nitrate reduction, with the pseudofirst-order rate constant for the adsorption increasing with increase in nanocomposite-to-nitrate ion ratio. Nitrate removal efficiency of zerovalent iron chitosan-humic acid nanocomposite was further confirmed using real water samples obtained from drainage waste and river with an initial nitrate concentration of and  ppm, respectively. The reduction of nitrate in water using the nanocomposite was concluded to be highly effective. Caroline Avosuahi Akinremi, Nikechukwu Nike Omosun, Sheriff Adewuyi, Jamiu Oladipupo Azeez, and Sanyaolu Nurudeen Olanrewaju Copyright © 2016 Caroline Avosuahi Akinremi et al. All rights reserved. The Influence of the MRSP on the Freezing and Evaporation Processes of the Magnesium Sulfate Subtype Salt Lake Brine Tue, 30 Aug 2016 15:41:23 +0000 We have developed a new concept, which is the mass fraction ratio of sulfate and potassium ions (MRSP), for the magnesium sulfate subtype salt lake, which is calculated using the metastable phase diagram. We also studied the trend of the MRSP values with the temperature and the influence of the MRSP values on the evaporation process. The experimental results indicated that the MRSP value showed significantly negative trend with decrease of refrigerated temperature. Moreover, when the MRSP value of the objective brine is reduced to less than or equal to the Specific Value by freezing operation, the great changes of crystal morphology and stage of K+ and will take place, which makes the sequence of salts precipitation of the freezing-evaporation different from the direct-evaporation. Qinghai Li, Kongjin Zhu, Yuntao Liu, Xingqiang Liu, Feng Li, Guoju Liu, Yong Yang, Yonghua Li, Shenglin Liu, and Wenyi Song Copyright © 2016 Qinghai Li et al. All rights reserved. Tribological Performance of Si-Doped Hydrogenated Diamond-Like Carbon Coatings in Different Biodiesel Sun, 21 Aug 2016 12:48:53 +0000 In this paper, two kinds of different biodiesel were tested in terms of their impact on wear resistance of Si-DLC coated 100Cr6 flat worn by an oscillating 100Cr6 ball. The knowledge about the tribological behaviour of different types of biodiesel is rare. Rape and soybean are two of the most common natural sources for biodiesel production. Also, if the quality of biodiesel seems to be similar and, according to the demands, biodiesel from different natural origin could affect changes in the tribological behaviour. Although, soybean methyl ester (SME) gives the best results at room temperature wear tests, 150°C SME reaches wear rates of Si-DLC flat against 100Cr6 ball almost double as high as rapeseed methyl ester (RME). It is evident that, with increasing fraction of oxidation stabilizer C23H32O2, the wear rate increases. For silicon doped hydrogenated diamond-like carbon is especially suitable, for use in biodiesels, where certain fraction of humidity, dissociated water, or polar functional groups may present. Annett Dorner-Reisel, Zeynep Burcu Kavaklioglu, Stefan Svoboda, and Jürgen Engemann Copyright © 2016 Annett Dorner-Reisel et al. All rights reserved. Preparation and Characterization of Polymer-Grafted Montmorillonite-Lignocellulose Nanocomposites by In Situ Intercalative Polymerization Wed, 17 Aug 2016 08:54:46 +0000 Lignocellulose-clay nanocomposites were synthesized using an in situ intercalative polymerization method at 60°C and a pressure of 1 atm. The ratio of the montmorillonite clay to the lignocellulose ranged from 1 : 9 to 1 : 1 (MMT clay to lignocelluloses, wt%). The adsorbent materials were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), and X-ray powder diffraction (XRD). FTIR results showed that the polymers were covalently attached to the nanoclay and the lignocellulose in the nanocomposites. Both TEM and XRD analysis showed that the morphology of the materials ranged from phase-separated to intercalated nanocomposite adsorbents. Improved thermal stability, attributable to the presence of nanoclay, was observed for all the nanocomposites. The nanocomposite materials prepared can potentially be used as adsorbents for the removal of pollutants in water treatment and purification. Tavengwa Bunhu, Nhamo Chaukura, and Lilian Tichagwa Copyright © 2016 Tavengwa Bunhu et al. All rights reserved. Identification and Optimisation of Lipase-Catalysed Synthesis of Betulinic Acid Amide in a Solvent System Sun, 17 Jul 2016 13:11:36 +0000 Betulinic acid amide was synthesized from the enzymatic reaction of betulinic acid and butylamine catalysed by Novozym 435. The effects of different reaction parameters, such as effect of reaction time, reaction temperature, amount of enzyme, and substrate molar ratio (betulinic acid : butylamine), were studied and conventionally optimised. Based on this study, the enzymatic synthesis of betulinic acid amide was found to be 64.6% at the optimum conditions of 24 h, 40°C, 100 mg enzyme, and 1 : 1 substrate molar ratio in 9 : 1 mixture of chloroform and hexane as solvent. The identification of final product was carried out using TLC, melting point, and FTIR and NMR showed the presence of betulinic acid amide. Nurul Atikah Binti Amin Yusof, Nursyamsyila Mat Hadzir, and Siti Efliza Ashari Copyright © 2016 Nurul Atikah Binti Amin Yusof et al. All rights reserved. Improved Biodegradable Radiation Cured Polymeric Film Prepared from Chitosan-Gelatin Blend Mon, 22 Feb 2016 13:39:13 +0000 The mechanical, thermal, swelling, and release properties of chitosan-gelatin (CG) films have been investigated in order to verify the influence of UV and gamma radiation on the stability of the films. Thin films of chitosan and gelatin (1 : 3, w/w) that were radiated with 100 krad of gamma dose showed the best performance and the TS values reached 25, 45, and 49 MPa, respectively, for chitosan, gelatin, and blend. The corresponding highest TS values were 23, 42, and 45 MPa, respectively, for 10 passes of UV radiation. The effect of radiation over gelatin, chitosan, and CG blend caused modification in the arrangement of molecules in the crystal lattice that is significant by XRD analysis. Surfaces of the films were also investigated by scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) studies further revealed structural changes of the films. These changes were attributed to understanding the behavior of the irradiated chitosan, gelatin, and CG blend on application of thermal energy using DSC and TGA studies, water uptake of the films in aqueous medium, and soil degradation properties to observe the best possibility for its application. Zinia Nasreen, Mubarak A. Khan, and A. I. Mustafa Copyright © 2016 Zinia Nasreen et al. All rights reserved. Extraction and Characterization of Fibres from the Stalk and Spikelets of Empty Fruit Bunch Thu, 09 Jul 2015 12:32:18 +0000 Fibres from different parts of empty fruit bunch, which is a major solid waste from oil palm processing, were subjected to different pretreatments and characterised for variability in length and diameter, mechanical performance, and proximate and trace element composition. Morphology and surface composition of the fibres were determined using scanning electron microscopy with energy dispersive X-ray. The fibres were further treated with KOH-boric acid and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. Fibre yield was higher for spikelet than stalk. Fibres from stalk were generally larger in diameter and showed significant differences in potassium and galacturonic acid content, strength, and rigidity. Scanning electron microscopy confirmed the widespread occurrence of silica bodies as well as significant differences in the microstructure of stalk and spikelet fibres. Stalk fibres showed a greater level of porosity than spikelet fibres in the section perpendicular to the major axis. The morphology of KOH-boric acid treated fibres suggested higher recalcitrance of spikelet fibres. The significant differences between fibres from stalk and spikelet suggest that EFB, used as feedstock for biobased industries, requires more systematic characterization and separation into stalk and spikelet, which may lead to a more judicious exploitation of this valuable waste. Yakum Reneta Nafu, Josepha Foba-Tendo, Ebenezer Njeugna, Gossett Oliver, and Kavian Omar Cooke Copyright © 2015 Yakum Reneta Nafu et al. All rights reserved. Insoluble Content, Ionic Composition, Density, and X-Ray Diffraction Spectra of 6 Evaporites from Niger Republic Thu, 07 May 2015 07:26:09 +0000 Some physicochemical (insoluble content, ionic composition, density, and X-ray diffraction spectra) characteristics of Nigerien evaporites were investigated in this study. The results obtained showed that trona is the main mineral contained in Agadez, Dirkou, Niamey, and Zinder evaporites while thenardite and halite constitute the major minerals in Bilma and Tabalak evaporites, respectively. In addition, all evaporites samples investigated revealed the presence of quartz and halite. Other interesting minerals (calcite, gypsum, sylvite, aphthitalite, nahcolite, illite, burkeite, kaolinite, griceite, and talc) were also detected. The use of Agadez, Dirkou, Niamey, and Zinder evaporites as catalyst to accelerate cowpea cooking is due to bicarbonates ions present in trona. Bilma and Tabalak evaporites employed in animal feeding are due to the halite contained in a significant quantity. Hassidou Saidou, Ahmed Hichem Hamzaoui, and Adel Mnif Copyright © 2015 Hassidou Saidou et al. All rights reserved. Microtron Irradiation Induced Tuning of Dielectric Properties of LDPE-ZnO Nanocomposites Mon, 23 Feb 2015 08:49:41 +0000 Low-density polyethylene (LDPE)/ZnO composites were prepared using melt mixing process. ZnO powder with size of 44 nm was used as reinforcing particle. The electron beam irradiation effects on the dielectric behaviour of a polymer nanocomposite dielectric made of low density polyethylene filled with nanoparticles of ZnO were studied. The dielectric constant and dielectric loss values were determined by dielectric spectroscopy over a frequency range of 100 KHz–5 MHz on plane samples of the tested nanodielectrics. The influence of filler concentration, between 2 and 8 wt.%, and the irradiation effects on the dielectric properties are also discussed in the paper. Deepu Thomas, Simon Augustine, and Jithin Prakash Copyright © 2015 Deepu Thomas et al. All rights reserved. Distribution Pattern of Metals in Atmospheric Settling Dust along Roads in Kano Metropolis, Nigeria Tue, 10 Feb 2015 07:33:30 +0000 The sequential extraction of Cd, Cr, Ni, Pb, Cu, and Zn in atmospheric dust particles collected along ten high traffic roads in Kano metropolis was carried out. Analyses of metals in the extracts were done using flame atomic absorption spectrometry (FAAS). The samples analyzed for metals indicated high levels of Cd, Cr, Ni, Pb, Cu, and Zn in the atmospheric dust samples. The sequential extractions that showed significant amount of Cd were associated with and Fe-MnO fractions especially during the dry seasons. For Cr and Ni, their occlusion in crystal lattice of the soil fraction exhibited the highest percentage. Pb in the particulate dust samples is significantly associated with the carbonate bound fraction with range of 8.81–64.69% across the season. The behaviour of Cu is quite different from other metals in that percentage fractions are higher in the organic bound. As for Zn, significant amounts were associated with the residue fractions ranging from 0.96 to 87.50% across the seasons. This study revealed contamination of the particulate dust with Cd and Pb; this implies health risks to human, living or carrying out daily activities along the corridors of these roads. O. J. Okunola, A. Uzairu, S. Uba, C. S. Ezeanyanaso, and Y. Alhassan Copyright © 2015 O. J. Okunola et al. All rights reserved. Proficient Procedure for Preparation of Quinoline Derivatives Catalyzed by NbCl5 in Glycerol as Green Solvent Wed, 21 Jan 2015 07:56:07 +0000 Quinolines, an important class of potentially bioactive compounds, have been synthesized by treatment of o-aminoaryl ketones and carbonyl compound utilizing niobium (V) chloride (NbCl5) as an available and inexpensive catalyst. The quinoline derivatives were prepared in glycerol, an excellent solvent in terms of environmental impact, with high yields (76–98%) and short reaction times (20–90 min). Not only diketones but also ketones afforded the desired products in good to excellent yields. The reaction time of 2-amino-5-chlorobenzophenone and dicarbonyl compounds was longer than that of 2-aminobenzophenone. The reaction of cyclic diketones took place faster than open chain analogues. These reactions also proceeded with acetophenone derivatives. In these cases the reaction times are longer. Mohammad Ali Nasseri, Batol Zakerinasab, and Sayyede Kamayestani Copyright © 2015 Mohammad Ali Nasseri et al. All rights reserved. Aminated β-Cyclodextrin-Modified-Carboxylated Magnetic Cobalt/Nanocellulose Composite for Tumor-Targeted Gene Delivery Wed, 31 Dec 2014 09:08:00 +0000 Gene therapy is a new kind of medicine, which uses genes as drugs in order to treat life threatening diseases. In the present work, a nonviral vector, aminated β-cyclodextrin-modified-carboxylated magnetic cobalt/nanocellulose composite (ACDC-Co/NCC), was synthesized for efficient transfection of genes into tumour cells. The synthesized ACDC-Co/NCC was characterized by means of FTIR, XRD, SEM, and ESR techniques. DNA condensing ability of ACDC-Co/NCC was found to be increased with increase in amount of ACDC-Co/NCC and 84.9% of DNA (1.0 μg/mL) inclusion was observed with 6.0 μg/mL of ACDC-Co/NCC. The cytotoxicity of ACDC-Co/NCC was observed to be minimal, even at higher concentration, with respect to the model transfecting agent, poly(ethyleneimine) (PEI). 88.2% of the gene was transfected at high dose of DNA, as indicated by the highest luciferase expression. These results indicated that ACDC-Co/NCC might be a promising candidate for gene delivery with the characteristics of good biocompatibility, potential biodegradability, minimal cytotoxicity, and relatively high gene transfection efficiency. Thayyath Sreenivasan Anirudhan and Sylaja Raveendran Rejeena Copyright © 2014 Thayyath Sreenivasan Anirudhan and Sylaja Raveendran Rejeena. All rights reserved. Fast Release of Sulfosalicylic Acid from Polymer Implants Consisting of Regenerated Cellulose/γ-Ferric Oxide/Polypyrrole Mon, 22 Dec 2014 06:55:03 +0000 This work presents a comparative study on the rate of drug release from implantable matrices induced by electric and magnetic fields separately for better biomedical applications. The matrices were prepared by coating γ-ferric oxide dispersed regenerated cellulose film by polypyrrole doped with sulfosalicylic acid as an anti-inflammatory drug. The drug release mechanisms were studied under both the electric and the magnetic fields separately in an acetate buffer solution with pH 5.5 and temperature 37°C during a period of 5 hours. The amount of drug released was analysed by UV-Vis spectrophotometry. The mechanism of drug release from the matrices under electric field includes expansion of conductive polymer chain and the electrostatic force between electron and drug. The drug release mechanism from the matrices under magnetic field is based on the fact that the heat produced locally by magnetic particles loosens the polymer (polypyrrole) chain surrounding the particles. As a result, the drugs attached to the polypyrrole chain come out to the release medium. The matrices showed fast release of drug, that is, more than 60% of the loaded drug was released within 1 h, and are ideal for the treatment of illness in an emergency care. Nargis A. Chowdhury, John Robertson, Ahmed Al-Jumaily, and Maximiano V. Ramos Copyright © 2014 Nargis A. Chowdhury et al. All rights reserved. Ultrasonic Investigations of Molecular Interaction in Binary Mixtures of Cyclohexanone with Isomers of Butanol Thu, 18 Dec 2014 07:30:28 +0000 Ultrasonic speed, , and density, , have been measured in binary liquid mixtures of cyclohexanone with the isomers of butanol (-butanol, sec-butanol, and tert-butanol) at 308.15 K over the entire range of composition. Molar volume (), adiabatic compressibility (), intermolecular free length (), acoustic impedance (), and their excess/deviation along with have been calculated from the experimental data. These values have been fitted to Redlich-Kister type polynomial equation. Positive values of , , and negative values of , have been observed for all the liquid mixtures indicating the existence of weak interactions between components. Rupture of H-bond or reduction in H-bond strength of isomers of butanol or breaking of the structure of one or both of the components in a solution causes the existence of dispersions in the present investigated binary mixtures. The data obtained from , , and excess partial molar volumes , , reflects the inferences drawn from . Furthermore, FTIR spectra support the conclusions drawn from excess/deviation properties. The measured values of ultrasonic speed for all the investigated mixtures have been compared with the theoretically estimated values using empirical relations such as, Nomoto, Van Dael and Vangeels, Impedance and Rao specific sound speed. Sk. Md Nayeem, M. Kondaiah, K. Sreekanth, and D. Krishna Rao Copyright © 2014 Sk. Md Nayeem et al. All rights reserved. Kinetics and Thermodynamic Studies of Depolymerization of Nylon Waste by Hydrolysis Reaction Mon, 08 Dec 2014 10:42:46 +0000 Depolymerization reaction of nylon waste was carried out by hydrolysis reaction. Yield of depolymerization products was up to 72.20% for a two-hour reaction time. The products obtained were characterized by melting point and FTIR spectra. The values obtained for dibenzoyl derivative of hexamethylenediamine (DBHMD) agreed with those of the pure substance. Chemical kinetics of this reaction shows that it is a first-order reaction with respect to hexamethylenediamine (HMD) concentration with velocity constant  min−1. The energy of activation and Arrhenius constant obtained by Arrhenius plot were 87.22 KJg−1 and 0.129, respectively. The other thermodynamic parameters such as enthalpy of activation () and entropy of activation () and free energy of activation were 5975.85 J and −270.86 J·K−1·mol−1 and 101.59 KJ·mol−1, respectively. D. B. Patil and S. V. Madhamshettiwar Copyright © 2014 D. B. Patil and S. V. Madhamshettiwar. All rights reserved. Characterization of Native and Modified Starches by Potentiometric Titration Wed, 03 Dec 2014 00:10:02 +0000 The use of potentiometric titration for the analysis and characterization of native and modified starches is highlighted. The polyelectrolytic behavior of oxidized starches (thermal and thermal-chemical oxidation), a graft copolymer of itaconic acid (IA) onto starch, and starch esters (mono- and diester itaconate) was compared with the behavior of native starch, the homopolymer, and the acid employed as a graft monomer and substituent. Starch esters showed higher percentages of acidity, followed by graft copolymer of itaconic acid and finally oxidized starches. Analytical techniques and synthesis of modified starches were also described. Diana Soto, Jose Urdaneta, and Kelly Pernia Copyright © 2014 Diana Soto et al. All rights reserved. Methods for Detection of Aflatoxins in Agricultural Food Crops Thu, 13 Nov 2014 06:18:27 +0000 Aflatoxins are toxic carcinogenic secondary metabolites produced predominantly by two fungal species: Aspergillus flavus and Aspergillus parasiticus. These fungal species are contaminants of foodstuff as well as feeds and are responsible for aflatoxin contamination of these agro products. The toxicity and potency of aflatoxins make them the primary health hazard as well as responsible for losses associated with contaminations of processed foods and feeds. Determination of aflatoxins concentration in food stuff and feeds is thus very important. However, due to their low concentration in foods and feedstuff, analytical methods for detection and quantification of aflatoxins have to be specific, sensitive, and simple to carry out. Several methods including thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), mass spectroscopy, enzyme-linked immune-sorbent assay (ELISA), and electrochemical immunosensor, among others, have been described for detecting and quantifying aflatoxins in foods. Each of these methods has advantages and limitations in aflatoxins analysis. This review critically examines each of the methods used for detection of aflatoxins in foodstuff, highlighting the advantages and limitations of each method. Finally, a way forward for overcoming such obstacles is suggested. Alex P. Wacoo, Deborah Wendiro, Peter C. Vuzi, and Joseph F. Hawumba Copyright © 2014 Alex P. Wacoo et al. All rights reserved. Studies on Mechanical, Thermal, and Morphological Properties of Glass Fibre Reinforced Polyoxymethylene Nanocomposite Thu, 06 Nov 2014 11:02:03 +0000 Polyoxymethylene is a material which has excellent mechanical properties similar to Nylon-6 filled with 30% GF. 75% POM and 25% glass fibre (POMGF) were blended with nanoclay to increase the tensile and flexural properties. Samples were extruded in twin screw extruder to blend POMGF and (1%, 3%, and 5%) Cloisite 25A nanoclay and specimens were prepared by injection moulding process. The tensile properties, flexural properties, impact strength, and hardness were investigated for the nanocomposites. The fibre pull-outs, fibre matrix adhesion, and cracks in composites were investigated by using scanning electron microscopy. 1% POMGF nanocomposite has low water absorption property. Addition of nanoclay improves the mechanical properties and thermal properties marginally. Improper blending of glass fibre and nanoclay gives low tensile strength and impact strength. SEM image shows the mixing of glass fibre and nanoclay among which 1% POMGF nanocomposite shows better properties compared to others. The thermal stability decreased marginally only with the addition of nanoclay. K. Mohan Babu and M. Mettilda Copyright © 2014 K. Mohan Babu and M. Mettilda. All rights reserved. Visual Detection and Determination of Melamine Using Synthetic Dyes Thu, 25 Sep 2014 10:51:43 +0000 We have used spectroscopic technique for the detection of melamine. The effect of melamine on the colour as well as the pH of bromophenol, methyl red and alizarin red dye solutions was examined at different mole ratios. It is found that we observe color transition and the absorption maxima for bromophenol were at 598 nm, while for methyl red, and alizarin red-S dye they are at 520 nm and 423 nm, respectively. We observe an increase in the absorption intensities at 598 nm with increase in the concentration of melamine in bromophenol blue dye. The absorption intensities at 520 nm decreases and new peak at 420 nm emerges in methyl red dye-melamine mixture. While the absorption intensities at 420 nm decreases and 520 nm peak emerges in alizarin red S dye-melamine at higher mole ratios. The results indicate that we can choose the appropriate dye of suitable range to detect the concentration of melamine from 3 to 206 mg dm−3. The results demonstrate possible use of the simple method for the qualitative and quantitative detection of melamine in adulterated food samples. Ramesh Thimmasandra Narayan and Kirana Devarahosahally Veeranna Copyright © 2014 Ramesh Thimmasandra Narayan and Kirana Devarahosahally Veeranna. All rights reserved. Industrial Waste-Derived Nanoparticles and Microspheres Can Be Potent Antimicrobial and Functional Ingredients Wed, 17 Sep 2014 12:31:45 +0000 Rapeseed oilcake or press-cake is generated as bulk waste during oil extraction from oilseeds. Owing to its high protein content, further processing of oilcakes into vegetable protein generates large quantities of fibrous residue (“oil-and-protein” spent meal) as by-product, which currently has very limited practical utility. Here, we report hydrothermal carbonization of this industrial waste to convert it into carbon nanoparticles, bestowed with multitude of functionalities. We demonstrate that these nanoparticles can be assembled into micrometer-sized spheres when precipitated from water by acetone. These microspheres, with their added feature of hemocompatibility, can be potentially utilized as an encapsulation vehicle for the protection of thermolabile compounds (such as protein); however, the secondary and tertiary features of the protein were marginally perturbed by the encapsulation process. The synthesized carbon nanoparticle was found to be an effective biocidal agent, exhibiting bacterial cellular damage and complex formation with the bacterial plasmid (evident from ethidium bromide exclusion assay), which are critical for cell survival. The results show the ability to convert industrial biowaste into useful nanomaterials for use in food industries and also suggest new scalable and simple approaches to improve environmental sustainability in industrial processes. Manashi Das Purkayastha, Ajay Kumar Manhar, Manabendra Mandal, and Charu Lata Mahanta Copyright © 2014 Manashi Das Purkayastha et al. All rights reserved. Averrhoa carambola: A Renewable Source of Oxalic Acid for the Facile and Green Synthesis of Divalent Metal (Fe, Co, Ni, Zn, and Cu) Oxalates and Oxide Nanoparticles Wed, 17 Sep 2014 12:12:48 +0000 A green, simple, and environmentally benign synthetic approach has been utilised to obtain some bivalent metal oxalates from Averrhoa carambola juice extract, without any purification or special treatment of the juice. The main acid components (oxalic acid and ascorbic acid) of the juice were identified by HPLC technique. The effect of temperature on the purity of the product has been investigated. The as-synthesized metal oxalates were thermally decomposed at low temperatures to their respective metal oxide nanoparticles. The metal oxalates and their respective thermal decomposition products were characterized by Fourier Transform Infrared spectroscopy, X-ray diffraction analysis, and thermogravimetry. Nguimezong Nguefack Marius Borel, Josepha Foba-Tendo, Divine Mbom Yufanyi, Ekane Peter Etape, Jude Namanga Eko, and Lambi John Ngolui Copyright © 2014 Nguimezong Nguefack Marius Borel et al. All rights reserved. Bioavailability Studies of Metals in Surface Water of River Challawa, Nigeria Mon, 15 Sep 2014 13:11:06 +0000 Due to industrialization of Kano City, more industries located within Challawa industrial estate have discharged waste informed of effluents into River Challawa, which is the main source of irrigation water for agricultural land. Hence, this study is aim at assessing the bioavailable fractions of the metals zinc (Zn), lead (Pb), copper (Cu), chromium (Cr) and cadmium (Cd) in surface water of river Challawa, Kano, Nigeria, across seasons. It was found that the concentrations of most metals increased significantly during the dry seasons. Concentrations of Cu and Zn are within the standard limits of EPA and WHO for these metals in drinking water while Pb, Cr, and Cd have their concentrations higher than EPA and WHO standard limits. Analysis of relationship between metals indicated significant positive correlation () between Cr and Zn, in all seasons with exception of warm and dry season. This might explain the consistent variation of these metals in the sites in a particular season. Also, significant negative correlation was observed between Cd and Cu (hot and dry season). The chemical fractionation trends were found to be dominated by particulate fractions of metals studied except Zn (cool and dry season) and Cd. The highest percentages of all metals analysed were found in the particulate fraction with exception of Cd. This could reflect less availability of this metal to the immediate environment. However, availability of metals such as Cd, Cr, and Pb in the dissolved and mobile fractions reflects the greater tendency to become available to the aquatic system and through the food chain to man. A. Uzairu, O. J. Okunola, R. J. Wakawa, and S. G. Adewusi Copyright © 2014 A. Uzairu et al. All rights reserved. Validation of a Serum Analysis Method to Analyze Antihistamines by Capillary Electrophoresis Mon, 25 Aug 2014 00:00:00 +0000 The validation of an electrophoresis-based analytical method to quantify 17 antihistamines in pharmaceutical formulations and serum is described. Then, whether the methodology provides true values with low uncertainty and is able to detect the concentration range level of analyte usually found in the matrix was evaluated. The analytical method was validated following the recommendations of an official guide to provide more reliability to the results. The ICH Harmonized Tripartite Guideline was selected because it was especially developed for analysis of drugs. The guide and the following required validation parameters, selectivity, calibration range, linearity, limit of detection, limit of quantification, inter- and intraday accuracy and precision, and robustness, were described. The method was inexpensive, fast, simple, environmentally friendly, and useful for routine analysis. The methodology was successfully validated and applied to commercial pharmaceutical formulations and spiked blank serum samples. J. Peris-Vicente, S. Carda-Broch, and J. Esteve-Romero Copyright © 2014 J. Peris-Vicente et al. All rights reserved. Processing and Properties of Carbon Nanotube PVC Composites Sun, 17 Aug 2014 08:03:55 +0000 Commercially available multiwalled carbon nanotubes (MWCNT) were incorporated in coating masses based on PVC by means of three roll mill. The best results could be obtained using the 5 µm gap. Thin PVC sheets were formed via knife coating having an electrical conductivity up to 1,500 S/m that are applicable as electric heating elements. For the use in the antistatic range, CNT contents ≤0.5% are sufficient. Rheological measurements indicate the quality of particle processing. AFM investigations are suitable to investigate the alignment of the nanoparticles in the bulk polymer. Using this method, the decrease of agglomerates as well as the splitting of CNT bundles within further mass processing could be visualized. Kristin Trommer, Carina Petzold, and Bernd Morgenstern Copyright © 2014 Kristin Trommer et al. All rights reserved. Electron Donor-Acceptor Interaction of 8-Hydroxyquinoline with Citric Acid in Different Solvents: Spectroscopic Studies Sun, 17 Aug 2014 06:27:03 +0000 Charge transfer complex formation between 8-hydroxyquinoline as the electron donor and citric acid as the electron acceptor has been studied spectrophotometrically in ethanol and methanol solvents at room temperature. Absorption band due to charge transfer complex formation was observed near 320 and 325 nm in ethanol and methanol, respectively. The stoichiometric ratio of the complex has been found 3 : 1 by using Job’s and conductometric titration methods. Benesi-Hildebrand equation has been applied to estimate the formation constant and molecular extinction coefficient. It was found that the value of formation constant was larger in ethanol than in methanol. The physical parameters, ionization potential, and standard free energy change of the formed complex were determined and evaluated in the ethanol and methanol solvents. Demelash Jado, Khalid Siraj, and Nathan Meka Copyright © 2014 Demelash Jado et al. All rights reserved. A Study of the Uptake of Heavy Metals by Plants near Metal-Scrap Dumpsite in Zaria, Nigeria Tue, 12 Aug 2014 09:45:56 +0000 The research work investigates the metal uptake of the plants Lycopersicon esculentum (tomato), Rumex acetosa (sorrel), and Solanum melongena (garden egg) collected from experimental sites and a control area in Zaria, Nigeria. The concentrations of Cd, Cu, Fe, Pb, Mn, and Zn in different parts of each of the plant species grown on the experimental and control soils were determined using atomic absorption spectrophotometry. The experimental levels of the metals were higher than those at the control site and the limits recommended by Food and Agricultural Organisation/World Health Organisation (FAO/WHO). Solanum melongena showed bioaccumulation factor (BF) and transfer factor (TF) greater than 1 for Cd, Pb, and Mn; Rumex acetosa showed BF and TF greater than 1 for Mn and Zn, and TF was greater than 1 for Cu and Fe; Lycopersicon esculentum had only the TF for Fe, Pb, Mn, and Zn greater than 1. This results implies that Solanum melongena and Rumex acetosa plants can be effectively used for phytoremediation of Cd, Pb, Mn, and Zn from the dumpsite. Pearson’s correlation coefficient values were greater than 0.75 for all the metals studied which indicated that the high metal level in the experimental soil was a result of the metal-scrap. Zakka Israila Yashim, Omoniyi Kehinde Israel, and Musa Hannatu Copyright © 2014 Zakka Israila Yashim et al. All rights reserved. Investigation of Regenerated Cellulose/Poly(acrylic acid) Composite Films for Potential Wound Healing Applications: A Preliminary Study Tue, 06 May 2014 06:25:03 +0000 Regenerated cellulose/poly(acrylic acid) composite films have been synthesized for wound dressing applications. The water absorbency of these films was studied as a function of amount of cross-linker N,N′-methylenebisacrylamide and cellulose contents in the feed mixture. The samples, having different compositions, showed tensile strength and percent elongation in the range of to  N/m2 and 110 to 265, respectively. The water vapor transmission rate (WVTR) for various films was found to be in the range of 2.03 to 7.18 mg/cm2/h. These films were loaded with antibacterial drug miconazole nitrate and their release was studied in the physiological pH at 37°C. The release data was found to fit well the diffusion controlled Higuchi model. Finally the films demonstrated fair antibacterial and antifungal action, thus establishing their strong candidature as wound dressing materials. Manjula Bajpai, S. K. Bajpai, and Dinesh Gautam Copyright © 2014 Manjula Bajpai et al. All rights reserved. Benign Methodology and Efficient Catalysis for the One-Pot Multicomponent Synthesis of Dihydropyrimidinones and Thiones: A New Key for Old Lock Wed, 09 Apr 2014 12:17:53 +0000 In the present communication, under the influence of microwaves, cuprous chloride has been demonstrated to be safe, mild, efficient, and inexpensive catalyst for the Biginelli discovered multicomponent reaction (MCR) between aromatic aldehydes, urea/substituted urea, and ethyl acetoacetate to produce structurally diverse dihydropyrimidin-2(1H)-ones (DHPMs) and thiones in an ecofriendly solvent-free protocol. The practical and simple protocol led to excellent yields of the dihydropyrimidin-2(1H)-one derivatives under mild reaction conditions and within short span of reaction times with easy reaction workup by maintaining excellent atom economy. Parvez Ali, Naziyanaz Pathan, and Taibi Ben Hadda Copyright © 2014 Parvez Ali et al. All rights reserved.