Journal of Chemistry The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. The Optimization of Matrix Preparation Process and Performance Testing for Molten Carbonate Fuel Cell Wed, 23 Apr 2014 11:55:36 +0000 A key component in the molten carbonate fuel cell (MCFC) is electrolyte matrix, which provides both ionic conduction and gas sealing. The aim of this work is to investigate the effects of selected operating conditions on the performance of the matrix preparation. Slurries were prepared to produce matrices by the technique of tape casting. The characteristics of the slurries and matrices were examined by laser particle size analyzer, scanning electron microscopy, and BET surface area analyzer. The testing results revealed that a slurry composition with 40 wt.% lithium aluminate was the optimal formulation to produce a good matrix with a pore size distribution of 0.1–0.4 μm and porosity of 50 vol.%. Coarse and fine LiAlO2 particles were added in the matrix slurry to enhance the mechanical strength. Several green sheets were heated and pressed to enhance the bulk density to get a dense matrix of MCFC. Finally, a single MCFC was assembled and tested. The testing results showed the matrix with 40% solid loading gave the maximum discharge current of 20 A at 0.56 V. Jian Cheng, Liejin Guo, Shisen Xu, and Ruiyun Zhang Copyright © 2014 Jian Cheng et al. All rights reserved. Pentafluoropropionic Acid: An Efficient and Metal-Free Catalyst for the One-Pot Synthesis of Tetrahydrobenzo[b]pyran Derivatives Wed, 23 Apr 2014 07:22:00 +0000 Pentafluoropropionic acid (PFPA) efficiently catalyzes the one-pot, three-component reaction of aromatic aldehyde, malononitrile, and dimedone to yield tetrahydrobenzo[b]pyran derivatives in high yields. This method is of great value because of its easy processing, short reaction time, environmentally, and high yields. Naser Montazeri, Taghva Noghani, Mona Ghorchibeigy, and Rozita Zoghi Copyright © 2014 Naser Montazeri et al. All rights reserved. Effect of Magnesium Borates on the Fire-Retarding Properties of Zinc Borates Tue, 22 Apr 2014 00:00:00 +0000 Magnesium borate (MB) is a technical ceramic exhibiting high heat resistance, corrosion resistance, great mechanical strength, great insulation properties, lightweightness, high strength, and a high coefficient of elasticity. Zinc borate (ZB) can be used as a multifunctional synergistic additive in addition to flame retardant additives in polymers. In this study, the raw materials of zinc oxide (ZnO), magnesium oxide (MgO), and boric acid (H3BO3) were used in the mole ratio of 1 : 1 : 9, which was obtained from preexperiments. Using the starting materials, hydrothermal synthesis was applied, and characterisation of the products was performed using X-Ray diffraction (XRD) and Fourier transform infrared (FT-IR) and Raman spectroscopies. The forms of Zn3B6O12·3.5H2O, MgO(B2O3)3·7(H2O), and Mg2(B6O7(OH)6)2·9(H2O) were synthesised successfully. Moreover, the surface morphology was investigated using scanning electron microscopy (SEM), and the B2O3 content was determined. In addition, the reaction yields were calculated. The results of the B2O3 content analysis were in compliance with the literature values. Examination of the SEM images indicated that the obtained nanoscale minerals had a reaction efficiency ranging between 63–74% for MB and 87–98% for ZB. Finally, the fire-retarding properties of the synthesised pure MBs, pure ZBs, and mixtures of MB and ZB were determined using differential thermal analysis and thermal gravimetry (DTA-TG) and differential scanning calorimetry (DSC). Azmi Seyhun Kipcak, Nil Baran Acarali, Emek Moroydor Derun, Nurcan Tugrul, and Sabriye Piskin Copyright © 2014 Azmi Seyhun Kipcak et al. All rights reserved. Evaluation on Antioxidant Effect of Xanthohumol by Different Antioxidant Capacity Analytical Methods Thu, 17 Apr 2014 16:41:38 +0000 Several assays have been frequently used to estimate antioxidant capacities including , DPPH, and FRAP assays. Xanthohumol (XN), the major prenylated flavonoid contained in beer, witnessed various reports on its antioxidant capacity. We systematically evaluated the antioxidant activity of XN using three systems, 2,2,-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid () scavenging assays, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assays, and ferric reducing antioxidant power (FRAP) assays. The results are expressed as Trolox equivalent antioxidant capacity (TEAC). The TEAC of XN was  μmol·l−1 by the ABTS assay and  μmol·l−1 by the FRAP. Meanwhile, the XN did not show obviously scavenging effect on DPPH radical reaction system. These results showed that different methods in the evaluation of compound antioxidant capicity, there may be a different conclusion. Xiu-Li Zhang, Yong-Dong Zhang, Tao Wang, Hong-Yun Guo, Qi-Ming Liu, and Hai-Xiang Su Copyright © 2014 Xiu-Li Zhang et al. All rights reserved. Study of Coating Geometries and Photoluminescence Properties of Metal Nanoparticles/Graphite Composites Thu, 17 Apr 2014 06:59:21 +0000 In this work we present the results of a study of growth and characterization of metal nanoparticles (Ag, Au, and Co)/carbon surfaces. The nanoparticles grew by laser ablation technique and their dimensions were controlled by light scattering study and AFM microscopy before their insertion on graphite surface. Nanoparticles appear randomly disposed on carbon surfaces aggregating to form big particles only in the case of silver. The different behavior of metal nanoparticles on carbon surface was explained in terms of different metal wetting of surface, in agreement with previous theoretical results of He et al. Chemical information, obtained by X-ray photoelectron spectroscopy, indicated that the doping process is a simple physisorption while the interfacial interaction between particles and carbon layers causes local defects in graphite structure and the appearance of a strong photoluminescence signal for all composites. Moreover, the visible optical absorption decreases about 10% indicating the progressive metallization of carbon surface. Pasquale Barone, Marianna Barberio, Fabio Stranges, and Fang Xu Copyright © 2014 Pasquale Barone et al. All rights reserved. Preparation of Schiff Base Derived from 3,4-Dimethoxybenzaldehyde and p-Aminobenzoic Acid by Supersonic Speed Gas Impacting Method Tue, 15 Apr 2014 09:01:25 +0000 A Schiff base derived from 3,4-dimethoxybenzaldehyde and p-aminobenzoic acid (SBDA) was synthesized by novel supersonic speed gas impacting method. The morphology and geometric structure of the synthesized Schiff base SBDA were investigated, the results showed that the particles of SBDA were not completely regular and the HOMO and LUMO of SBDA optimized geometry structure using the semiempirical method PM3 were −9.115 eV and −1.191 eV, respectively, and some bond length of synthesized SBDA became short and bone angle became large compared to the reactant. The thermogravimetric analysis results indicated that SBDA began to decompose above 280°C; the decomposition temperature and thermogravimetric rate could vary with the different heating rate. Yan-Hua Cai and Wen Luo Copyright © 2014 Yan-Hua Cai and Wen Luo. All rights reserved. Salt Effect on the Cloud Point Phenomenon of Amphiphilic Drug-Hydroxypropylmethyl Cellulose System Sun, 13 Apr 2014 00:00:00 +0000 Effect of two amphiphilic drugs (tricyclic antidepressant, nortriptyline hydrochloride (NORT), and nonsteroidal anti-inflammatory drug, sodium salt of ibuprofen (IBF)) on the cloud point of biopolymer hydroxypropylmethyl cellulose (HPMC) was studied. Effect of NaCl was also seen on the CP of HPMC-drug system. CP of HPMC increases uniformly on increasing the (drug). Both drugs, though one being anionic (IBF) and other cationic (NORT), affect the CP in almost the same manner but with different extent implying the role of hydrophobicity in the interaction between drug and polymer. Salt affects the CP of the drug in a dramatic way as low concentration of salt was only able to increase the value of the CP, though not affecting the pattern. However, in presence of high concentration of salts, minimum was observed on CP versus (drug) plots. Various thermodynamic parameters were evaluated and discussed on the basis of the observed results. Mohd. Sajid Ali, Dileep Kumar, and Hamad A. Al-Lohedan Copyright © 2014 Mohd. Sajid Ali et al. All rights reserved. Study on Nonequilibrium Effect of Condensate Gas Reservoir with Gaseous Water under HT and HP Condition Wed, 09 Apr 2014 14:25:42 +0000 When a condensate gas reservoir with gaseous water under high temperature and high pressure condition is producing, the gaseous water and nonequilibrium effect will have great influences on the phase behavior of condensate oil and gas system and the accumulation of condensate liquid near the wellbore area. Therefore, a series of experiments were performed to investigate phase behavior of the condensate gas reservoirs with gaseous water using a PVT cell, in which the constant volume depletion process of nonequilibrium pressure drop and equilibrium pressure drop within near wellbore zone was simulated. And using the modified PR EOS, PR EOS, and nonequilibrium effect theory, the authors calculated the content of condensate oil and condensate liquid of the nonequilibrium pressure drop and equilibrium pressure drop and compared the calculated results with the experimental data. The results show that the modified PR EOS combined with nonequilibrium effect theory is more suitable for representing phase behavior characteristics of the development process of condensate gas reservoir containing gaseous water, with the average relative error of 4.49%. Furthermore, choosing the appropriate exploiting opportunity and properly increasing the nonequilibrium effect are helpful to increase condensate oil and water recovery. Dali Hou, Pingya Luo, Lei Sun, Yong Tang, and Yi Pan Copyright © 2014 Dali Hou et al. All rights reserved. Study of Band Gap of Silver Nanoparticles—Titanium Dioxide Nanocomposites Wed, 09 Apr 2014 07:33:04 +0000 The optical and chemical properties of Ag/TiO2 nanocomposites were investigated to explore the possibilities of incorporating these new materials in Gratzel photoelectrochemical cells. The nanocomposites were obtained doping TiO2, in both allotropic species anatase and rutile, with silver nanoparticles (grown by laser ablation process). X-ray photoelectron data indicate the absence of Ag-Ti chemical bonds, while measurements of photoluminescence and optical absorbance in UV-visible range show a quench in photoluminescence emission of about 50% and an increase in visible absorbance of about 20%. Measurements of optical band gap, obtained by Tauc’s equation, indicate a variation of about 1.6 eV. P. Barone, F. Stranges, M. Barberio, D. Renzelli, A. Bonanno, and F. Xu Copyright © 2014 P. Barone et al. All rights reserved. The Wiener Index of Circulant Graphs Wed, 09 Apr 2014 07:26:30 +0000 Circulant graphs are an important class of interconnection networks in parallel and distributed computing. In this paper, we discuss the relation of the Wiener index and the Harary index of circulant graphs and the largest eigenvalues of distance matrix and reciprocal distance matrix of circulants. We obtain the following consequence: ; ; , where W, H denote the Wiener index and the Harary index and λ, μ denote the largest eigenvalues of distance matrix and reciprocal distance matrix of circulant graphs, respectively. Moreover we also discuss the Wiener index of nonregular graphs with cut edges. Houqing Zhou Copyright © 2014 Houqing Zhou. All rights reserved. Synthesis, Characterization, Electrochemistry, and Spectroscopic Properties of Some Anthracenyl Functionalized Phthalocyanine Complexes of Ruthenium(II) Mon, 07 Apr 2014 09:36:35 +0000 The synthesis of single- and double-decked anthracenyl functionalized ruthenium(II) phthalocyanine complexes has been achieved through a controlled electrophilic aromatic substitution reaction of the free unsubstituted ruthenium(II) phthalocyanine with preformed 9-bromo-10-(2,3-dimethylacrylic acid)-anthracene and/or 9-bromo-10-(2,3-dimethylacrylic acid)-dianthracene using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as catalyst. The complexes were characterized by IR, UV-Vis, fluorescence, 1H, 13C NMR, and elemental analyses. A dimeric complex (, where is 9-dianthracenyl-10-(2,3-dimethylacrylic acid), obtained as the major product of the dianthracenyl-substituted ruthenium phthalocyanine complex displays a strong near-infrared visible absorption band wavelength maxima at 1027 nm ( M−1 cm−1), with an interesting photoluminescent and electroredox active properties. Adewale O. Adeloye and Peter A. Ajibade Copyright © 2014 Adewale O. Adeloye and Peter A. Ajibade. All rights reserved. Synthesis and Biological Evaluation of New Substituted 3-[4-(Phenylsulfonamido)benzoyl]-2H-1-benzopyran-2-one Derivatives as α-Glucosidase Inhibitors Sun, 06 Apr 2014 12:15:45 +0000 A series of new substituted 3-[4-(phenylsulfonamido)benzoyl]-2H-1-benzopyran-2-one derivatives bearing groups methoxy, tert-butyl, and atoms of halogens at the para-position of the A-ring were synthesized and in vitro biological activities were evaluated as nonsugar α-glucosidase inhibitors. Most of the test compounds demonstrated significant α-glucosidase inhibitory activity relative to that of Acarbose (IC50 = 29.26 μM). The para-substitution with a methoxy group or halogens could notably increase the potency. Compounds 17, 18, and 23, with IC50 values of 0.025 μM, 0.014 μM, and 0.018 μM, respectively, may be of significance for the further development of new nonsugar α-glucosidase inhibitors. Yu-ling Wang, Ting-jian Zhang, Jing-wei Liang, Fan-hao Meng, and Shao-jie Wang Copyright © 2014 Yu-ling Wang et al. All rights reserved. Retracted: Improvement of Landfill Leachate Biodegradability with Ultrasonic Process Mon, 31 Mar 2014 12:13:06 +0000 Journal of Chemistry Copyright © 2014 Journal of Chemistry. All rights reserved. Evaluation of Antibacterial Enrofloxacin in Eggs by Matrix Solid Phase Dispersion-Flow Injection Chemiluminescence Sun, 30 Mar 2014 09:08:25 +0000 The study based on the chemiluminescence (CL) reaction of potassium ferricyanide and luminol in sodium hydroxide medium, enrofloxacin (ENRO) could dramatically enhance CL intensities and incorporated with matrix solid-phase dispersion (MSPD) technique (Florisil used as dispersant, dichloromethane eluted the target compounds). A simple flow injection chemiluminescence (FL-CL) method with MSPD technique for determination of ENRO in eggs was described. Under optimal conditions, the CL intensities were linearly related to ENRO concentration ranging from  g.L−1 to  g.L−1, with a correlation coefficient of 0.9989 and detection limit of  g.L−1. The relative standard deviation was 3.6% at an ENRO concentration of  g.L−1. Our testing technique can help ensure food safety, and thus, protect public health. Xiaocui Duan, Pingping Zhang, Jing Feng, and Ning Jiao Copyright © 2014 Xiaocui Duan et al. All rights reserved. Adding Value to Agricultural Products and Agrifood Byproducts by Highlighting Functional Ingredients Thu, 27 Mar 2014 00:00:00 +0000 Souhail Besbes, Hamadi Attia, and Christophe Blecker Copyright © 2014 Souhail Besbes et al. All rights reserved. Reactivity of Alkyldibenzothiophenes Using Theoretical Descriptors Wed, 26 Mar 2014 11:59:17 +0000 Theoretical calculations of the reactivity of dibenzothiophene and its methyl, dimethyl, and trimethyl derivatives show that local reactivity descriptors reproduce their experimental desulfurization reactivity trend if the first desulfurization step involves directly the sulfur atom, which only occurs if the sulfur atom is blocked at most by one methyl group. In the series of molecules 4,7-dimethyldibenzothiophene, ,4,7-trimethyldibenzothiophene (), the most reactive molecule is 2,4,7-trimethyldibenzothiophene, and local descriptors show that the reactivity is linked to the activity of the sulfur atom, which is higher in 2,4,7-trimethyldibenzothiophene due to the position of the third methyl substitute, located in the para position with respect to the carbon bonded to the sulfur atom. The electrostatic potential of 2,4,7-trimethyldibenzothiophene shows one effective adsorption site, while 1,4,7-trimethyldibenzothiophene and 3,4,7-trimethyldibenzothiophene have more sites, contributing to the higher reactivity of 2,4,7-trimethyldibenzothiophene. The index of reactivity of other descriptors was evaluated and the effect of the position of the methyl substituents on adsorption parameters, as the dipole moment and the atomic charges were also studied. Jose Luis Rivera, Pedro Navarro-Santos, Luis Hernandez-Gonzalez, and Roberto Guerra-Gonzalez Copyright © 2014 Jose Luis Rivera et al. All rights reserved. Functionalized Nanocomposites for Environmental Applications Wed, 26 Mar 2014 10:48:10 +0000 Tifeng Jiao, Lavinia Balan, Xinqing Chen, and Qingrui Zhang Copyright © 2014 Tifeng Jiao et al. All rights reserved. Anodic Dissolution of API X70 Pipeline Steel in Arabian Gulf Seawater after Different Exposure Intervals Tue, 25 Mar 2014 15:23:46 +0000 The anodic dissolution of API X70 pipeline steel in Arabian Gulf seawater (AGSW) was investigated using open-circuit potential (OCP), electrochemical impedance spectroscopy (EIS), cyclic potentiodynamic polarization (CPP), and current-time measurements. The electrochemical experiments revealed that the X70 pipeline steel suffers both general and pitting corrosion in the AGSW solution. It was found that the general corrosion decreases as a result of decreasing the corrosion current density (), corrosion rate () and absolute currents as well as the increase of polarization resistance of X70 with increasing the exposure time. On the other hand, the pitting corrosion was found to increase with increasing the immersion time. This was confirmed by the increase of current with time and by the SEM images that were obtained on the steel surface after 20 h immersion before applying an amount of 0–.35 V versus Ag/AgCl for 1 h. El-Sayed M. Sherif and Abdulhakim A. Almajid Copyright © 2014 El-Sayed M. Sherif and Abdulhakim A. Almajid. All rights reserved. Surface Structure and Catalytic Performance of Ni-Fe Catalyst for Low-Temperature CO Hydrogenation Mon, 24 Mar 2014 14:54:35 +0000 Catalysts 16NiFe/Al2O3 ( is 0, 1, 2, 4, 6, 8) were prepared by incipient wetness impregnation method and the catalytic performance for the production of synthetic natural gas (SNG) from CO hydrogenation in slurry-bed reactor were studied. The catalysts were characterized by BET, XRD, UV-Vis DRS, H2-TPR, CO-TPD, and XPS, and the results showed that the introduction of iron improved the dispersion of Ni species, weakened the interaction between Ni species and support and decreased the reduction temperature and that catalyst formed Ni-Fe alloy when the content of iron exceeded 2%. Experimental results revealed that the addition of iron to the catalyst can effectively improve the catalytic performance of low-temperature CO methanation. Catalyst 16Ni4Fe/Al2O3 with the iron content of 4% exhibited the best catalytic performance, the conversion of CO and the yield of CH4 reached 97.2% and 84.9%, respectively, and the high catalytic performance of Ni-Fe catalyst was related to the property of formed Ni-Fe alloy. Further increase of iron content led to enhancing the water gas shift reaction. Fanhui Meng, Pengzhan Zhong, Zhong Li, Xiaoxi Cui, and Huayan Zheng Copyright © 2014 Fanhui Meng et al. All rights reserved. Polyvinyl chloride Waste as an Adsorbent for the Sorption of from Aqueous Solution Mon, 24 Mar 2014 07:28:19 +0000 The sorption of Pb2+ from solution by polyvinyl chloride waste was investigated. The morphological features of the polymer sample were studied using the energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), and the Fourier transform infrared spectroscopy (FTIR). Equilibrium, kinetic, and thermodynamic batch adsorption experiments were carried out by the concentration, time, and temperature effects, respectively. The morphological image of the polymer showed irregular small size particles which indicated a high surface area and porosity that facilitated sorption. The adsorption studies recorded relatively rapid uptake of Pb2+ by the polymer which was mainly diffusion controlled and followed a second order kinetic process. The thermodynamic studies suggested relatively low temperature (low energy) favoured sorption which was exothermic with a physisorption mechanism. Donbebe Wankasi and Ezekiel Dixon Dikio Copyright © 2014 Donbebe Wankasi and Ezekiel Dixon Dikio. All rights reserved. Study on the Matching Relationship between Polymer Hydrodynamic Characteristic Size and Pore Throat Radius of Target Block S Based on the Microporous Membrane Filtration Method Wed, 19 Mar 2014 13:02:10 +0000 The concept of the hydrodynamic characteristic size of polymer was proposed in this study, to characterize the size of aggregates of many polymer molecules in the polymer percolation process. The hydrodynamic characteristic sizes of polymers used in the target block S were examined by employing microporous membrane filtration method, and the factors were studied. Natural core flow experiments were conducted in order to set up the flow matching relationship plate. According to the flow matching plate, the relationship between the hydrodynamic characteristic size of polymer and pore throat radius obtained from core mercury injection data was found. And several suitable polymers for different reservoirs permeability were given. The experimental results of microporous membrane filtration indicated that the hydrodynamic characteristic size of polymer maintained a good nonlinear relationship with polymer viscosity; the value increased as the molecular weight and concentration of the polymer increased and increased as the salinity of dilution water decreased. Additionally, the hydrodynamic characteristic size decreased as the pressure increased, so the hydrodynamic characteristic size ought to be determined based on the pressure of the target block. In the core flow studies, good matching of polymer and formation was identified as polymer flow pressure gradient lower than the fracture pressure gradient of formation. In this case, good matching that was the pore throat radius should be larger than 10 times the hydrodynamic characteristic size of polymer in this study. Using relationship, more matching relationship between the hydrodynamic characteristic sizes of polymer solutions and the pore throat radius of target block was determined. Li Yiqiang, Gao Junxin, Yin Dandan, Li Junjian, and Liu Hualong Copyright © 2014 Li Yiqiang et al. All rights reserved. An Efficient Synthesis of Phenols via Oxidative Hydroxylation of Arylboronic Acids Using (NH4)2S2O8 Mon, 17 Mar 2014 08:05:10 +0000 A mild and efficient method for the ipso-hydroxylation of arylboronic acids to the corresponding phenols was developed using (NH4)2S2O8 as an oxidizing agent. The reactions were performed under metal-, ligand-, and base-free conditions. Claudia A. Contreras-Celedón, Luis Chacón-García, and Nancy Judith Lira-Corral Copyright © 2014 Claudia A. Contreras-Celedón et al. All rights reserved. Dissolution and Solubility of the ()HAsO4·H2O Solid Solution in Aqueous Solution at 25°C and pH 2 Mon, 17 Mar 2014 07:15:50 +0000 Six different members of the ()HAsO4·H2O solid solution were prepared and characterized, and then dissolution of the synthetic solids was studied at 25°C and pH 2 in a series of batch experiments for 4320 h. With the increase in the Ba/() mole fraction of the solids, the aqueous pH decreased and the aqueous barium concentration increased. The aqueous strontium and arsenic concentrations had the highest values at . The solubility products for BaHAsO4·H2O and SrHAsO4·H2O were calculated to be and , respectively. The corresponding free energies of formation were determined to be − kJ/mol and − kJ/mol. The solid solution had a minimum solubility product of at . The Guggenheim coefficients were determined to be and . The Lippmann diagram was a typical Lippmann diagram for a nonideal solid solution with a negative enthalpy of mixing. The system shows an “alyotropic” minimum at the aqueous activity fraction of 0.87 where the solutus and solidus curves meet. At the end of the dissolution experiment, the dissolution followed the saturation curve for the pure endmember BaHAsO4·H2O and approached the intersection with the minimum stoichiometric saturation curve on the Lippmann diagram. Xuehong Zhang, Yinian Zhu, Caichun Wei, Zongqiang Zhu, and Zongning Li Copyright © 2014 Xuehong Zhang et al. All rights reserved. Effect of Mn Content and Solution Annealing Temperature on the Corrosion Resistance of Stainless Steel Alloys Thu, 13 Mar 2014 09:51:04 +0000 The corrosion behavior of two specially designed austenitic stainless steels (SSs) having different Nickel (Ni) and Manganese (Mn) contents was investigated. Prior to electrochemical tests, SS alloys were solution-annealed at two different temperatures, that is, at 1030°C for 2 h and 1050°C for 0.5 h. Potentiodynamic polarization (PD) tests were carried out in chloride and acidic chloride, whereas linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) was performed in 0.5 M NaCl solution at room temperature. SEM/EDS investigations were carried out to study the microstructure and types of inclusions present in these alloys. Experimental results suggested that the alloy with highest Ni content and annealed at 1050°C/0.5 hr has the highest corrosion resistance. Ihsan-ul-Haq Toor Copyright © 2014 Ihsan-ul-Haq Toor. All rights reserved. The Study of Pyridazine Compounds on Prostanoids: Inhibitors of COX, cAMP Phosphodiesterase, and TXA2 Synthase Thu, 13 Mar 2014 08:51:08 +0000 The pyridazine moiety is an important structural feature of various pharmacological active compounds. Synthetic pyridazine compounds have been reported as effective antiprostaglandins (PGs), 5-lipoxygenase (5-LOX), and antiplatelet agents, that is, inhibitors of prostaglandin or cyclooxygenase (COX-I & COX-II) enzyme, platelet cAMP phosphodiesterase, and thromboxane A2 (TXA2) synthase. These compounds are selective and nonselective COX inhibitors and showed analgesic, anti-inflammatory, and antipyretic activity. Pyridazine compounds with antiplatelet agents inhibited TXA2 enzyme. Pyridazines also exhibited antirheumatoid activity. These pyridazine compounds hold considerable interest relative to the preparation of organic intermediates and other anticipated biologically active compounds. Mohammad Asif Copyright © 2014 Mohammad Asif. All rights reserved. Synthesis of 1,8-Naphthyridine Derivatives under Ultrasound Irradiation and Cytotoxic Activity against HepG2 Cell Lines Wed, 12 Mar 2014 08:39:41 +0000 Novel pyrazole derivatives 3a,b, 5, 1,3,4-oxadiazole 6, 1,3,4-thiadiazole 8, and 1,2,4-triazole 9a–c incorporated into 1,8-naphthyridine have been synthesized using the versatile synthon 2-(2,7-dimethyl-1,8-naphthyridin-4-yloxy) acetohydrazide 1. An improvement in rates and yields was observed when the reactions were carried out under ultrasonic irradiation compared with the classical synthesis. The newly synthesized compounds were evaluated for HepG2 cell growth inhibition. The results obtained revealed that the tested compounds possess inhibitory effect on the growth of HepG2 liver cancer cells. The results were compared to doxorubicin (DOX) as a reference drug (IC50 : 0.04 M). Compounds 9b showed the highest inhibition activity against HepG2 cell line (IC50 : 0.048 M) among all tested compounds. N. S. Ahmed, K. O. AlFooty, and S. S. Khalifah Copyright © 2014 N. S. Ahmed et al. All rights reserved. Regioselective Synthesis of Some Pyrazole Scaffolds Attached to Benzothiazole and Benzimidazole Moieties Mon, 10 Mar 2014 16:25:45 +0000 Condensation of 2-(benzothiazol-2-yl)acetonitrile (1) or 2-(1-methyl-1H-benzimidazol-2-yl)acetonitrile (2) with thiophene-2-carbaldehyde afforded the corresponding acrylonitrile derivatives 3 or 4, respectively. The 1,3-dipolar cycloaddition reaction of the acrylonitrile 3 or 4 with nitrile-imine 6 gave novel pyrazole derivatives pendant to benzothiazole and benzimidazole. The pyrazoline derivative 7 was converted into the corresponding pyrazole derivative 11 via thermal elimination of hydrogen cyanide upon heating in sodium ethoxide solution. The structures of the synthesized products were confirmed by IR, 1H NMR, and mass spectral techniques. Nabila A. Kheder, Yahia N. Mabkhot, Fawzia R. Zahian, and Sara S. Mohamed Copyright © 2014 Nabila A. Kheder et al. All rights reserved. Improving Anti-Protein-Fouling Property of Polyacrylonitrile Ultrafiltration Membrane by Grafting Sulfobetaine Zwitterions Mon, 10 Mar 2014 16:00:39 +0000 Zwitterions show great superiority in the field of polymer membrane surface functionalization, as the synthesis process is simple, the adaptability of functional groups is strong, and zwitterions with strong hydration capacity in aqueous solutions can inhibit protein adsorption. In this study, a polyacrylonitrile ultrafiltration membrane was modified to improve anti-protein-fouling capacity by grafting short-chain sulfonic type zwitterions. 3-Dimethylaminopropylamine was first grafted onto hydrolyzed polyacrylonitrile (PAN) membrane by the activation of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC). Subsequently, sulfobetaine zwitterions emerged on the membrane surface by quaternization of 1,3-propane sultone. The sulfobetaine zwitterionic membranes were analyzed for surface chemical composition, hydrophilic properties, and surface and cross-sectional structure of the membrane, by a combination of Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, contact angle measurement, and scanning electron microscopy. Static protein adsorption and dynamic filtration experiments were undertaken to show that the modified membrane had excellent resistance to protein adsorption. It was found that the molecular weight cutoff of the substrate membrane had great influence on the flux recovery rate of the modified membrane. Hong Meng, Qiang Cheng, Haizhi Wang, and Chunxi Li Copyright © 2014 Hong Meng et al. All rights reserved. Photodegradation of HCFC-22 Using Microwave Discharge Electrodeless Mercury Lamp with TiO2 Photocatalyst Balls Thu, 06 Mar 2014 11:48:02 +0000 The photodegradation of chlorodifluoromethane (HCFC-22) was investigated using microwave/UV/TiO2 photocatalysts hybrid system. The microwave discharge electrodeless mercury lamp (MDEML) used in this study showed mainly atomic Hg emission lines at 253.7 nm. The decomposition efficiency of HCFC-22 increased with decreasing inlet concentration and with increasing reactor residence time. The removal efficiency increased with increasing microwave power on every oxygen concentration. The highest degradation efficiency was obtained when both TiO2 balls and MDEML were used. Seong-Gyu Seo, Young-Kwon Park, Sun-Jae Kim, Heon Lee, and Sang-Chul Jung Copyright © 2014 Seong-Gyu Seo et al. All rights reserved. The Cooperative Effect of In2O2 and In/HZSM-5 for Reduction of Nitric Oxide with Methane Tue, 04 Mar 2014 14:11:31 +0000 Compared with In/HZSM-5 catalyst, In/HZSM-5/In2O3 catalyst that contained two different kinds of In induced by the impregnation and the physical mixing method, respectively, has shown remarkable activity for methane selectively catalytic reduction (CH4-SCR) of NOx. The addition of In2O3 to In/HZSM-5 could improve the NO conversion. When a little In2O3 was added to the In/HZSM-5, the active sites of InO+ which can adsorb NO2 were increased. Moreover, at the internal surface of HZSM-5, highly dispersed In2O3 species could promote oxidation of NO to NO2. The adsorption of NO2 is the key step for the whole reaction, which benefits the activation of methane and the reduction of NOx by methane. Thus the activity of In/HZSM-5/In2O3 for CH4-SCR of NOx was higher than that of In/HZSM-5. Lili Ren Copyright © 2014 Lili Ren. All rights reserved.