Journal of Applied Chemistry The latest articles from Hindawi © 2017 , Hindawi Limited . All rights reserved. A Simple Incorporation Route of Tris(8-hydroxyquinoline)aluminum(III) into Transparent Mesoporous Silica Films and Their Photofunctions Mon, 14 Aug 2017 00:00:00 +0000 The molecular aggregation states of tris(8-hydroxyquinoline)aluminum(III) (Alq) adsorbed in the transparent mesoporous silica (MPS) films with the different pore sizes (3.0 and 5.4 nm) were successfully clarified. The Alq molecules were easily incorporated into the films from the solution without the segregation on the surfaces. The adsorbed amount of Alq was controlled by changing the added amount in the initial solution to resultantly give the transparent and yellow-color films. The photoluminescence spectra significantly revealed that the state of Alq molecules in the mesopore varied depending on the adsorbed amount of Alq as well as the pore size, suggesting the characteristic mobility of the adsorbed Alq molecules in the mesopores as compared with that at the bulk or solution state. Therefore, the guest-guest interactions between Alq molecules as well as the host-guest interactions between Alq and mesopore were elucidated. This finding by the use of the mesoporous film hosts will be utilized for including luminescence species and be applicable for optical devices. Motohiro Tagaya, Kenji Shinozaki, and Yuri Maruko Copyright © 2017 Motohiro Tagaya et al. All rights reserved. New Pharmacophore from the Stem Bark Fractions of Acacia decurrens (Willd), an Invasive South Africa Tree Wed, 02 Aug 2017 00:00:00 +0000 The tolerance of Acacia decurrens, an invasive species, was exploited pharmacologically in this study. Phytochemical screening revealed important secondary metabolites. Importantly, the assay shows that ethyl acetate and methanol fractions are sources of phytochemicals compared to the hexane and chloroform fractions. A bioassay-guided in vitro assay of the extracts led to the eventual isolation of four bioactive compounds by column chromatography, identification, and characterisation with the aid of GCMS, UV-Vis, FTIR, and NMR. The antimicrobial screening by disc diffusion assay revealed 22.2%, 44.4%, 66.7%, and 77.8% microbial inhibition by 2-methyl-octahydro-indene-4-carboxylic acid (AD1), 6-methyldecahydro-1H-phenanthren-9-one (AD2), 8-hydroxytetradecahydro-chrysene-1-carb aldehyde (AD3), and 8,9-dihydroxy-7-(2-hydroxy-ethyl)-9,9a-hexahydro-1H,3H-2-thia-5a-aza cyclopenta[b]anthracen-6-one (AD4), respectively. Compounds AD3 and AD4 are the most potent antibacterial compounds against Gram-positive bacteria with MIC 12.5–6.25 μg/ml. Antioxidant study of the compounds assayed with DPPH and ABTS•+ revealed that compound (AD4) is the most efficient DPPH radical scavenger with IC50 30.07 ± 0.31 and ABTS•+ scavenging activity of 4363.2 ± 452.4 μmol of TE/gDW. This provides scientific information on four pharmacophores with phyto-antioxidants and antimicrobial potential, despite the classification of A. decurrens as a Category 2 invasive plant by the National Water Act. Bamidele Joseph Okoli and Johannes Sekomeng Modise Copyright © 2017 Bamidele Joseph Okoli and Johannes Sekomeng Modise. All rights reserved. Removal of Fluoride from Water by Adsorption onto Fired Clay Pots: Kinetics and Equilibrium Studies Tue, 04 Jul 2017 06:29:45 +0000 Excessive fluoride in potable water is a serious health problem in rural areas of many developing countries. Hence, there is a need to find a simple and cost-effective method for water defluoridation in such areas. In the northern part of Cameroon, clay pots are used for cooking food and water storage. The firing of these pots consists of intensive burning using fire wood. They were tested as a potential adsorbent for removing excess fluoride from water. Experiments were carried out in a jar test at room temperature (25 ± 2°C). Effects of contact time (0–90 min), pH (4, 5, 7, 8, and 9), stirring speed (60, 90, 120, and 200 rpm), and ionic strength (0–1000 mg/L) were investigated. Results showed that equilibrium was attained in 10 min whatever the pH. Pseudo-second-order and pore diffusion models described well the adsorption process. The highest amount of fluoride adsorbed (1.6 mg/g) was obtained at pH 4-5 and the optimum stirring speed is 120 rpm. Ionic strength has a significant effect on fluoride adsorption. G. P. Kofa, V. H. Gomdje, C. Telegang, and S. Ndi Koungou Copyright © 2017 G. P. Kofa et al. All rights reserved. Synthesis and Characterization of CuO, TiO2, and CuO-TiO2 Mixed Oxide by a Modified Oxalate Route Sun, 04 Jun 2017 00:00:00 +0000 Copper oxide (CuO), titanium oxide (TiO2), and Cu-doped TiO2 nanoparticles have been synthesized by pyrolysis of their corresponding precursors initially prepared by precipitation in aqueous solution using A. carambola fruit juice as a natural source of the precipitating agent (oxalate). The precursors were synthesized and characterized by FTIR, TGA, and PXRD. The results revealed that the precursors obtained were CuC2O4, TiO2(OH−)2C2O4, copper-doped titanium hydroxyl oxalate, and copper titanium hydroxyl oxalate. Complete decomposition for the as-prepared precursors containing titanium ions occurs at 600°C while impurity free copper oxalate decomposed at 450°C. The as-prepared precursors were decomposed and calcined at 600°C for 4 hours and the calcination products were characterized by XRD, SEM, and EDX. The results revealed the decomposition products to correspond to CuO, TiO2, Cu0.131Ti0.869O2, and CuO/TiO2. Ekane Peter Etape, Lambi John Ngolui, Josepha Foba-Tendo, Divine Mbom Yufanyi, and Beckley Victorine Namondo Copyright © 2017 Ekane Peter Etape et al. All rights reserved. Physicochemical Properties of Diacetylenic Light Fuel Oil from Congolese Oleaginous Plant Ongokea gore (Hua) Pierre Thu, 02 Mar 2017 00:00:00 +0000 Vegetable oil-based fuels are promising alternative fuels for diesel and light fuel engines because of their environmental and economic strategic advantages. In this study, Ongokea gore oil (OGO) and its fully hydrogenated oil were transesterified by means of ethanol in the presence of sodium ethoxide. Fatty acid ethyl esters (FAEE) products were confirmed by 1H NMR and characterized by physical-chemical methods in accordance with the ASTM D 6751 and AFNOR M 15-009 specifications for biodiesels and light biofuels. These methods concern determination of color, density, viscosity, flash and pour points, ash, water and sulfur contents, and corrosion on copper. It was found that pure fatty acid ethyl esters of Ongokea gore oil (B100) and its hydrogenated oil (B100-H) meet standard requirements for most of the biodiesel characteristics studied. Only the kinematic viscosity and density values were outside recommended biodiesel standard limits which makes them unsuitable for use in diesel engines. In accordance with the AFNOR M 15-009 specifications of light fuels, they can be used in light fuel engines. Physical-chemical properties of B20, a FAEE blend in petrodiesel, are within the limits prescribed for petrodiesel standards. In brief, Ongokea gore seeds, a nonedible and high-oil-producing feedstock, are suitable starting material for production of light biofuel. The latter blends in petrodiesel can be used as fuel in diesel engines. J. K. Ntumba, A. Mulula, K. T. Kashishi, M. N. Mifundu, R. Robiette, and K. M. Taba Copyright © 2017 J. K. Ntumba et al. All rights reserved. Investigation of Coagulation Activity of Cactus Powder in Water Treatment Wed, 30 Nov 2016 14:11:13 +0000 This paper is focused on the comparative study of cactus powder, Alum, and their combination of physiochemical analyses of water sample such as TDS, pH, conductivity, salinity, and turbidity using jar test. The result indicated that percentage removal of turbidity from turbid water sample increased from 23.9% to 54% and 28.46% to 58.2% as dose increased from 0.50 to 3.50 g for both cactus powder and Alum, respectively. Cactus powder also has a marginal effect on pH value (7.33 at 0.50 g, 7.49 at 1.50 g, 7.57 at 2.50 g, and 7.57 at 3.50 g) as compared to the usage of chemical coagulants (Alum). The salinity was increased from 0.4% to 0.69 % and 0.39% to 0.98% as the dose of cactus powder and Alum increased from 0.50 g to 3.50 g, respectively. The result revealed that cactus powder is more effective in pH upholding, TDS maintenance, and salinity removal than Alum, but their combination is the most effective in terms of turbidity removal, reduction of salinity, reduction of conductivity, and reduction of TDS and has a marginal effect on dissolved oxygen (DO) value. In conclusion, the combination of Alum and cactus powder is more effective for turbidity removal, salinity removal, and pH and conductivity upholding than either of them used individually. Hayelom Dargo Beyene, Tessema Derbe Hailegebrial, and Worku Batu Dirersa Copyright © 2016 Hayelom Dargo Beyene et al. All rights reserved. A Novel Tris(2-aminoethyl)amine Based Tripodal Ligand: Synthesis and Solution Coordination Studies with Trivalent Iron and Chromium Wed, 23 Nov 2016 14:15:05 +0000 A novel tris(2-aminoethyl)amine (TREN) based tripodal ligand TRENOL (L) has been synthesized and characterized by elemental analysis and UV-VIS, IR, 1H, and 13C NMR spectroscopic methods. The coordination behaviour of the ligand with H+ and trivalent metal ions, Fe(III) and Cr(III), was investigated in aqueous medium at 0.1 M KCl at °C by potentiometric and spectrophotometric studies. Tripodal ligand showed seven protonation constants in the adopted pH range 2–11 and its electronic spectra exhibited three bands at 216, 323, and 423 nm. Ligand formed various metal complex species of the type MLH5, MLH4, MLH3, MLH, and ML with trivalent metal ions. The determined values of the formation constants (for ML species) of the ligand with Fe(III) and Cr(III) were 24.19 and 18.64, respectively. Molecular modeling studies revealed that the metal complexes formed distorted octahedral geometry. Besides, ligand showed fluorescence at 496 nm when excited at 289 nm. The fluorescence behaviour of the ligand in the presence of Fe(III) ions showed noticeable quenching in comparison to the other metal ions at physiological pH (7.4). So, as per the outcomes of the present study, TRENOL has the potential to be used as the iron detector in environmental, agricultural, and medical fields. Minati Baral, Amit Gupta, Rifat Akbar, and Bikram K. Kanungo Copyright © 2016 Minati Baral et al. All rights reserved. Comparison of Surface and Structural Properties of Carbonaceous Materials Prepared by Chemical Activation of Tomato Paste Waste: The Effects of Activator Type and Impregnation Ratio Tue, 22 Nov 2016 09:37:20 +0000 Activated carbons were prepared by carbonization of tomato paste processing industry waste at 500°C followed by chemical activation with KOH, K2CO3, and HCl in N2 atmosphere at low temperature (500°C). The effects of different activating agents and impregnation ratios (25, 50, and 100 wt.%) on the materials’ characteristics were examined. Precursor, carbonized tomato waste (CTW), and activated carbons were characterized by using ultimate and proximate analysis, thermogravimetric analysis (TG/DTG), Fourier transform-infrared (FT-IR) spectroscopy, X-ray fluorescence (XRF) spectroscopy, point of zero charge measurements (), particle size analyzer, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, nitrogen adsorption/desorption isotherms, and X-ray diffraction (XRD) analysis. Activation process improved pore formation and changed activated carbons’ surface characteristics. Activated carbon with the highest surface area (283 m3/g) was prepared by using 50 wt.% KOH as an activator. According to the experimental results, tomato paste waste could be used as an alternative precursor to produce low-cost activated carbon. Nurgul Ozbay and Adife Seyda Yargic Copyright © 2016 Nurgul Ozbay and Adife Seyda Yargic. All rights reserved. Synthesis, X-Ray Crystal Structure Study, Hirshfeld Surface Analysis, and Biological Activity of N-(2-amino-phenyl)-2-methyl-benzamide Mon, 14 Nov 2016 12:56:07 +0000 The title compound crystallizes in monoclinic crystal system, with space group . The compound exhibits intermolecular interactions of the types N–H⋯N, C–H⋯O, and C–H⋯π; intramolecular interactions of the type N–H⋯N. The intercontacts are also studied using Hirshfeld surface analysis. The compound showed no remarkable antibacterial activity when screened against two gram-negative and two gram-positive bacteria. Latha Rani Nagaraju, Lakshmi Ranganatha Venkataravanappa, Sridhar Mandayam Anandalwar, and Shaukath Ara Khanum Copyright © 2016 Latha Rani Nagaraju et al. All rights reserved. Saccharomyces cerevisiae Catalyzed Cyclocondensation Reaction: Synthesis of Pyrazoline Tue, 25 Oct 2016 13:32:19 +0000 A simple, efficient, and environment friendly method has been developed for the synthesis of pyrazoline by the cyclocondensation of chalcones and hydrazine hydrate using very cheaper catalyst, baker’s yeast (Saccharomyces cerevisiae). The 3,5-diphenyl pyrazolines are synthesized in moderate to good yield. The method also overcomes drawbacks of the previous pyrazoline synthetic methods and provides a new efficient route to 3,5-diphenyl pyrazoline derivatives. Nitesh D. Punyapreddiwar, Atul V. Wankhade, Sangesh P. Zodape, and Umesh R. Pratap Copyright © 2016 Nitesh D. Punyapreddiwar et al. 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.