Journal of Chemistry http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Ligand Synthesis Catalyst and Complex Metal Ion: Multicomponent Synthesis of 1,3-Bis(4-phenyl-[1,2,3]triazol-1-yl)-propan-2-ol Copper(I) Complex and Application in Copper-Catalyzed Alkyne-Azide Cycloaddition Thu, 05 May 2016 06:57:06 +0000 http://www.hindawi.com/journals/jchem/2016/6432492/ A new bistriazole copper complex was synthesized by direct treatment of an alkyne, an azide, and CuI as copper salt through in situ ligand formation under a multicomponent reaction process. This complex was analyzed by XPS, TGA, DSC, and SEM techniques and revealed a triangular-shaped morphology, high thermal stability, and catalytic power in CuAAC reactions, requiring only 2.5% mol catalyst to afford 1,2,3-triazoles in good yields which can be reused at least for 4 cycles. María Teresa Ramírez-Palma, Jesús Segura-Arzate, Gustavo López-Téllez, and Erick Cuevas-Yañez Copyright © 2016 María Teresa Ramírez-Palma et al. All rights reserved. Two New 1,1,3,3-Tetramethylguanidinium Halochromates (C5H14N3CrO3X) (X: Cl, F): Efficient Reagents for Oxidation of Organic Substrates under Solvent-Free Conditions and Microwave Irradiation Tue, 03 May 2016 15:46:53 +0000 http://www.hindawi.com/journals/jchem/2016/3518102/ Two new mild oxidizing agents 1,1,3,3-tetramethylguanidinium fluorochromate (TMGFC) and 1,1,3,3-tetramethylguanidinium chlorochromate (TMGCC) were prepared in high yields by reacting tetramethylguanidine with CrO3 and related acid. These reagents are suitable to oxidize various primary and secondary alcohols and oximes to the corresponding carbonyl compounds under solvent-free conditions and microwave irradiation. Kıvılcım Şendıl, H. Beytiye Özgün, and Ebru Üstün Copyright © 2016 Kıvılcım Şendıl et al. All rights reserved. Ultrasmall, Ligand-Free Ag Nanoparticles with High Antibacterial Activity Prepared by Pulsed Laser Ablation in Liquid Tue, 03 May 2016 10:08:54 +0000 http://www.hindawi.com/journals/jchem/2016/4143560/ Since ancient times, silver and its compounds have been known to have a broad spectrum of antimicrobial activities for bacteria, fungi, and viruses. Due to the increasing bacterial resistance to classic antibiotics, the investigations of Ag NPs have increased. Herein, we present the preparation of ligand-free Ag NPs with 3 and 20 nm sizes by applying picosecond laser ablation in liquid at 355 and 1065 nm. Our laser processing system allows a high control on particle sizes. The produced nanoparticles were characterized by means of transmission electron microscopy, UV-Vis spectroscopy, and X-ray diffraction. The size effect on the antibacterial activity of Ag NPs was tested against E. coli and S. aureus. The growth curves of bacteria were monitored at 0–5 mg/L of Ag NPs by a multimode microplate reader. The size effects as well as the concentration of Ag NPs on their antibacterial activity are discussed. László Kőrösi, Marina Rodio, Dora Dömötör, Tamás Kovács, Szilvia Papp, Alberto Diaspro, Romuald Intartaglia, and Szabolcs Beke Copyright © 2016 László Kőrösi et al. All rights reserved. α-Amylase and α-Glucosidase Inhibitory Saponins from Polyscias fruticosa Leaves Sat, 30 Apr 2016 10:54:53 +0000 http://www.hindawi.com/journals/jchem/2016/2082946/ Three bisdesmosidic saponins 3-O-[β-D-glucopyranosyl-(14)-β-D-glucuronopyranosyl] oleanolic acid 28-O-β-D-glucopyranosyl ester (1), polyscioside D (2), and 3-O--D-glucopyranosyl-(12)-[β-D-glucopyranosyl-(14)]-β-D- oleanolic acid 28-O-β-D-glucopyranosyl-(12)-β-D-galactopyranosyl ester (3) were isolated from a methanol extract of Polyscias fruticosa (L.) Harms leaves. Compound 1 was obtained as a main constituent and compound 3 was reported for the first time and named as polyscioside I. Saponin 1 inhibited porcine pancreas α-amylase and yeast α-glucosidase activities while 2 and 3 were inactive. Synergistic inhibitory effect on α-amylase was observed from the combination of low concentrations of 1 and acarbose. The findings suggest the use of P. fruticosa and its major saponin 1 for the prevention and treatment of diabetes and its complications. Tran Thi Hong Hanh, Nguyen Hai Dang, and Nguyen Tien Dat Copyright © 2016 Tran Thi Hong Hanh et al. All rights reserved. (+)-CSA Catalyzed Multicomponent Synthesis of 1-[(1,3-Thiazol-2-ylamino)methyl]-2-naphthols and Their Ring-Closure Reaction under Ultrasonic Irradiation Thu, 28 Apr 2016 16:18:59 +0000 http://www.hindawi.com/journals/jchem/2016/9315614/ New 1-[(1,3-thiazol-2-ylamino)methyl]-2-naphthols were obtained by condensation of 2-aminothiazole, aromatic aldehydes, and 2-naphthol in the presence of (+)-camphor-10-sulfonic acid ((+)-CSA) as an effective catalyst under ultrasound-promoted solvent-free conditions. The 1-[(1,3-thiazol-2-ylamino)methyl]-2-naphthol derivatives were converted in ring-closure reaction with formaldehyde to the corresponding naphthoxazine derivatives. Emel Pelit and Zuhal Turgut Copyright © 2016 Emel Pelit and Zuhal Turgut. All rights reserved. Antioxidant Composition of a Selection of Italian Red Wines and Their Corresponding Free-Radical Scavenging Ability Thu, 28 Apr 2016 11:08:15 +0000 http://www.hindawi.com/journals/jchem/2016/4565391/ This study correlates the antioxidant composition profiles and the overall antioxidant capacities of 36 Italian red wine samples. The samples were fully characterized by chromatographic and spectrophotometric techniques. The overall antioxidant capacity was determined by titrating a solution of the semistable free radical DPPH (1,1-diphenyl-2-picrylhydrazyl) with each wine sample followed by Electron Paramagnetic Resonance (EPR) spectroscopy and then measuring the resulting decrease in DPPH-signal. The antioxidant activities of the samples were expressed as (+)-catechin equivalents and related to their antioxidant composition profiles. Samples with a high polyphenol content showed a high DPPH scavenging ability as well. Seven well-defined groups, mainly constituted by wines coming from the same cultivar, were evidenced by PCA analysis. Alcohol content and pH did not influence the wine DPPH scavenging ability. The most important variables contributing to the wines’ antioxidant power are total flavonoid, total phenol, and proanthocyanidin indices together with fertaric acid, trans-caftaric acid, trans-coutaric acid, and both quercetin glucoside and quercetin glucuronide. EPR is demonstrated to be faster than the other analytical methods (spectrophotometric and chromatographic analyses) to determine the wine overall antioxidant activity. Claudio Cassino, Valentina Gianotti, Federica Bonello, Christos Tsolakis, Maria Carla Cravero, and Domenico Osella Copyright © 2016 Claudio Cassino et al. All rights reserved. Activation of Sphalerite by Ammoniacal Copper Solution in Froth Flotation Wed, 27 Apr 2016 09:28:18 +0000 http://www.hindawi.com/journals/jchem/2016/7614890/ The activation of sphalerite particles by ammoniacal copper solution (ACS) was investigated in this study. This microflotation study was conducted on a single sphalerite mineral with the particles size of 38 μm to 75 μm. Results showed that ACS has somewhat better activation effect than copper sulphate (a traditional activator) with sodium isobutyl xanthate as the collector. Agglomeration observation, contact angle measurement, and X-ray photoelectron spectroscopy measurement results of sphalerite particles verified the superiority of this new activator. Therefore, the substitution of copper sulphate with ACS would increase the separation efficiency not only in marmatite flotation but also in sphalerite flotation. Xian Xie, Kai Hou, Bo Yang, and Xiong Tong Copyright © 2016 Xian Xie et al. All rights reserved. Highly Selective Synthesis of Chlorophenols under Microwave Irradiation Tue, 26 Apr 2016 13:09:14 +0000 http://www.hindawi.com/journals/jchem/2016/2960414/ Oxychlorination of various phenols is finished in 60 minutes with high efficiency and perfect selectivity under microwave irradiation. These reactions adopt copper(II) chloride (CuCl2) as the catalyst and hydrochloric acid as chlorine source instead of expensive and toxic ones. Oxychlorination of phenols substituted with electron donating groups (methyl, methoxyl, isopropyl, etc.) at ortho- and meta-positions is accomplished with higher conversion rates, lower reaction time, and excellent selectivity. A proposed reaction mechanism is deduced; one electron transfers from CuCl2 to phenol followed by the formation of tautomeric radical that can be rapidly captured by chlorine atom and converts into para-substituted product. Yawen Xiong, Hongdong Duan, Xia Meng, Zhaoyun Ding, and Weichun Feng Copyright © 2016 Yawen Xiong et al. All rights reserved. Synthesis and Characterization of Poly(urethane-ether azomethine) Fatty Amide Based Corrosion Resistant Coatings from Pongamia glabra Oil: An Eco-Friendly Approach Sun, 24 Apr 2016 12:16:16 +0000 http://www.hindawi.com/journals/jchem/2016/5623126/ A novel attempt has been made to incorporate azomethine group in the backbone of polyurethane ether Pongamia oil fatty amide. The overall reaction was carried out in different steps like preparation of N,N-bis(2-hydroxyethyl) Pongamia glabra oil fatty amide, poly(ether fatty amide), and poly(urethane-ether) fatty amide. The hydroxyl terminated Schiff base, ethane 1,2-di(azomethine) bisphenol, reacts with fatty amide diol and is further treated with toluylene 2,4-diisocynate (TDI) to form poly(urethane-ether azomethine) fatty amide (PUEAF). These synthesized resins were characterized by FT IR, 1H NMR, and 13C NMR spectroscopic techniques. Molecular weight of PUEAF resin was measured by gel permeation chromatography (GPC), coating was made on mild steel strips, and evaluating their physicochemical and physicomechanical analysis was carried out by standard methods. The PUEAF25 coating showed highest scratch hardness (2.5 kg), gloss (90) at 45°, pencil hardness (4H), and impact resistance (150 lb/inch). Atomic force microscopy (AFM) and differential scanning calorimetry (DSC)/thermogravimetric analysis (TGA) were used to determine the topography and thermal behavior of PUEAF. Corrosion studies of PUEAF coated mild steel were used in different corrosive media (3.5 wt% HCl, 5 wt% NaCl, and tap water) at room temperature using potentiodynamic polarization technique. The results of this study showed that PUEAF coatings exhibit good physicomechanical, anticorrosive properties and get application up to 180°C. Manawwer Alam, Naser M. Alandis, Naushad Ahmad, and Mu Naushad Copyright © 2016 Manawwer Alam et al. All rights reserved. The Coffee Protective Effect on Catalase System in the Preneoplastic Induced Rat Liver Sun, 24 Apr 2016 11:47:15 +0000 http://www.hindawi.com/journals/jchem/2016/8570321/ This study aimed to evaluate the effect of organic/conventional coffee in liver tissues in the cancer process, taking into account the level and activities of catalase. The experiments were carried out with 8 groups of rats during 12 weeks. They received two injections of ethylenediaminetetraacetic acid solution 1.5% (v/v) prepared in 0.9% NaCl or 1,2-dimethylhydrazine (DMH) subcutaneous dose of 40 mg·kg−1·bw−1 for 2 weeks. The organic/conventional coffee infusions were at 5, 10, and 20% and were incorporated to feed (100 mL of infusion·kg−1 of diet). The catalase activity showed a decrease for livers which received DMH and DMH plus organic coffee at 5% and 10%. However, an increase was observed for those receiving organic 20% and conventional 10% coffee, slowing down and favoring the reversibility of the carcinogenic process. By SDS-PAGE, we observed an intensity decrease of 59 kDa bands, as the percentage of coffee was increased. The iron concentration (by ET-AAS) confirmed the electrophoretic results, suggesting that the DMH influenced the catalase expression conditions, reducing the activity by the loss of iron ions. Thus, the coffee may restore the catalase system in the liver, exerting its chemopreventive effects. Cristiana Schmidt de Magalhães, Jéssica Emi Takarada, Nathália Costa Carvalho, Dayene do C. Carvalho, Felipe Lopes de Andrade, Eric Batista Ferreira, Pedro Orival Luccas, and Luciana Azevedo Copyright © 2016 Cristiana Schmidt de Magalhães et al. All rights reserved. Impact of Roasting on Fatty Acids, Tocopherols, Phytosterols, and Phenolic Compounds Present in Plukenetia huayllabambana Seed Sun, 24 Apr 2016 08:02:20 +0000 http://www.hindawi.com/journals/jchem/2016/6570935/ The effect of roasting of Plukenetia huayllabambana seeds on the fatty acids, tocopherols, phytosterols, and phenolic compounds was evaluated. Additionally, the oxidative stability of the seed during roasting was evaluated through free fatty acids, peroxide, and p-anisidine values in the seed oil. Roasting conditions corresponded to 100, 120, 140, and 160°C for 10, 20, and 30 min, respectively. Results indicate that roasting temperatures higher than 120°C significantly affect the content of the studied components. The values of acidity, peroxide, and p-anisidine in the sacha inchi oil from roasted seeds increased during roasting. The treatment of 100°C for 10 min successfully maintained the evaluated bioactive compounds in the seed and quality of the oil, while guaranteeing a higher extraction yield. Our results indicate that P. huayllabambana seed should be roasted at temperatures not higher than 100°C for 10 min to obtain snacks with high levels of bioactive compounds and with high oxidative stability. Rosana Chirinos, Daniela Zorrilla, Ana Aguilar-Galvez, Romina Pedreschi, and David Campos Copyright © 2016 Rosana Chirinos et al. All rights reserved. Greenhouse Gases Emissions from Wastewater Treatment Plants: Minimization, Treatment, and Prevention Thu, 21 Apr 2016 14:13:47 +0000 http://www.hindawi.com/journals/jchem/2016/3796352/ The operation of wastewater treatment plants results in direct emissions, from the biological processes, of greenhouse gases (GHG) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), as well as indirect emissions resulting from energy generation. In this study, three possible ways to reduce these emissions are discussed and analyzed: minimization through the change of operational conditions, treatment of the gaseous streams, and prevention by applying new configurations and processes to remove both organic matter and pollutants. In current WWTPs, to modify the operational conditions of existing units reveals itself as possibly the most economical way to decrease N2O and CO2 emissions without deterioration of effluent quality. Nowadays the treatment of the gaseous streams containing the GHG seems to be a not suitable option due to the high capital costs of systems involved to capture and clean them. The change of WWTP configuration by using microalgae or partial nitritation-Anammox processes to remove ammonia from wastewater, instead of conventional nitrification-denitrification processes, can significantly reduce the GHG emissions and the energy consumed. However, the area required in the case of microalgae systems and the current lack of information about stability of partial nitritation-Anammox processes operating in the main stream of the WWTP are factors to be considered. J. L. Campos, D. Valenzuela-Heredia, A. Pedrouso, A. Val del Río, M. Belmonte, and A. Mosquera-Corral Copyright © 2016 J. L. Campos et al. All rights reserved. Ecotoxicity and Preliminary Risk Assessment of Nonivamide as a Promising Marine Antifoulant Thu, 21 Apr 2016 14:04:30 +0000 http://www.hindawi.com/journals/jchem/2016/2870279/ The unclear environmental performance of nonivamide limits its application as a marine antifoulant. In this study, the natural degradation of nonivamide was studied in seawater and tap water. The half-life was 5.8 d, 8.8 d, 12.2 d, and 14.7 d in seawater and tap water in photolysis and biolysis, respectively. Furthermore, the ecotoxicity of nonivamide was assessed using marine microalgae, Chlorella vulgaris and Platymonas sp.; values on the growth of Chlorella vulgaris and Platymonas sp. were 16.9 mg L−1 and 19.21 mg L−1, respectively. The toxicity and environmental risk of nonivamide on microalgae were significantly decreased due to the natural degradation in seawater. Sujing Liu, Jun Zhou, Xuanxuan Ma, Ying Liu, Xing Ma, and Chuanhai Xia Copyright © 2016 Sujing Liu et al. All rights reserved. Identifying Antioxidant and Antimicrobial Activities of the Phenolic Extracts and Mineral Contents of Virgin Olive Oils (Olea europaea L. cv. Edincik Su) from Different Regions in Turkey Thu, 21 Apr 2016 07:47:15 +0000 http://www.hindawi.com/journals/jchem/2016/9589763/ The objective of this study was to identify the antioxidant and antimicrobial activities of the phenolic extracts and mineral contents of virgin olive oils (Olea europaea L. cv. Edincik Su) obtained from three different locations, Edincik, Gomec, and Izmir, in Turkey. Antioxidant activity was analysed spectrometrically, antimicrobial effect was evaluated by disc diffusion method, and mineral contents were determined by using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Total phenolic contents and free radical scavenging activities of Edincik Su olive cultivar were found between 159.99 and 189.64 mg gallic acid equivalent/kg and 21.76 and 31.79% inhibition of DPPH• radical values, respectively. Phenolic composition was also varied according to location and hydroxytyrosol and tyrosol were determined as major phenolic compounds. Fourteen pathogenic bacteria and two fungal strains were used to determine the antimicrobial activity. Phenolic extracts showed antimicrobial effect against a wide range of microorganisms and the descending rank of the antimicrobial activities was Gomec, Izmir, and Edincik samples. The highest antimicrobial activities were determined against Clostridium perfringens ATCC 13124 and Campylobacter jejuni ATCC  33291 in all samples. Sixteen elements were used as standards (eleven of them were heavy metals) to identify mineral contents. Fe, Mg, Sn, K, and Ca were determined in Gomec samples and Mg and K were detected in Edincik samples while no mineral content was detected in Izmir sample. Ayhan Dağdelen Copyright © 2016 Ayhan Dağdelen. All rights reserved. Recent Advances in the Total Synthesis of Tetramic Acid-Containing Natural Products Wed, 20 Apr 2016 07:06:08 +0000 http://www.hindawi.com/journals/jchem/2016/8510278/ With incredible bioactivities and fascinating structural complexities, tetramic acid- (TA-) containing natural products have attracted favorable attention among the organic chemistry community. Although the construction of the TA core is usually straightforward, the intricate C3-side chain sometimes asks for some deliberative strategy so as to fulfill an elegant total synthesis. This review mainly covers some exceptional synthetic examples for each type of natural product in recent years, showcasing the great achievements as well as unsettled obstacles in this area, in the hope of accelerating the synthetic and biological investigations for this unique type of natural product. Wen-Ju Bai, Chen Lu, and Xiqing Wang Copyright © 2016 Wen-Ju Bai et al. All rights reserved. Fenton Process Coupled to Ultrasound and UV Light Irradiation for the Oxidation of a Model Pollutant Tue, 19 Apr 2016 11:39:30 +0000 http://www.hindawi.com/journals/jchem/2016/4262530/ The Fenton process coupled to photosonolysis (UV light and Us), using Fe2O3 catalyst supported on Al2O3, was used to oxidize a model pollutant like acid green 50 textile dye (AG50). Dye degradation was followed by AG50 concentration decay analyses. It was observed that parameters like iron content on a fixed amount of catalyst supporting material, catalyst annealing temperature, initial dye concentration, and the solution pH influence the overall treatment efficiency. High removal efficiencies of the model pollutant are achieved. The stability and reusability tests of the Fe2O3 catalyst show that the catalyst can be used up to three cycles achieving high discoloration. Thus, this catalyst is highly efficient for the degradation of AG50 in the Fenton process. Karen E. Barrera-Salgado, Gabriela Ramírez-Robledo, Alberto Álvarez-Gallegos, Carlos A. Pineda-Arellano, Fernando Z. Sierra-Espinosa, J. Alfredo Hernández-Pérez, and Susana Silva-Martínez Copyright © 2016 Karen E. Barrera-Salgado et al. All rights reserved. A New Phase of GaN Thu, 14 Apr 2016 16:16:24 +0000 http://www.hindawi.com/journals/jchem/2016/8612892/ The structural, mechanical, and electronic properties of the orthorhombic GaN (Pnma-GaN) are investigated at ambient pressure by using first-principles calculations method with the ultrasoft pseudopotential scheme. The elastic constants and phonon calculations reveal Pnma-GaN is mechanically and dynamically stable at ambient pressure. The calculated Young modulus of Pnma-GaN is 170 GPa, which is the three-fifths of wurtzite-GaN. Electronic structure study shows that Pnma-GaN is a direct semiconductor with band gap of 1.847 eV. The anisotropic calculation shows that wurtzite-GaN has a smaller elastic anisotropy than that of Pnma-GaN in Young’s modulus. In addition, when the composition of aluminum increases from 0 to 0.063 in the alloy, the band gap decreases initially and increases afterward for Pnma-Ga1−xAlxN, while, for wurtzite-Ga1−xAlxN, the band gap increases with the increasing composition x. Due to the structural porous feature, Pnma-GaN can also be expected to be a good hydrogen storage material. Qingyang Fan, Changchun Chai, Qun Wei, Jionghao Yang, Peikun Zhou, Dongyun Zhang, and Yintang Yang Copyright © 2016 Qingyang Fan et al. All rights reserved. AC Humidity Sensing Properties of Mesoporous K2CO3-SiO2 Composite Materials Mon, 11 Apr 2016 14:34:45 +0000 http://www.hindawi.com/journals/jchem/2016/3508307/ The mesoporous silica SBA-15 and mesoporous K2CO3-SiO2 composite material were synthesized. Characterization of microstructure and morphology of materials indicated that the composite material had saved the porous framework of mesoporous silica SBA-15. Humidity sensing properties of different inverse proportion K2CO3-SiO2 composite material were studied and we found that the sample with 0.16 g/g K2CO3 exhibited excellent linearity in the wide humidity range. The complex impedance changed five orders of magnitude from 11% RH to 95% RH. The rapid response and recovery time were 10 s and 38 s, respectively. Finally a feasible ion transfer mechanism was brought forward to explain the sensing mechanism. Liang Guo, Xuefeng Chu, Xiaohong Gao, Chao Wang, Yaodan Chi, and Xiaotian Yang Copyright © 2016 Liang Guo et al. All rights reserved. Permeability Characteristics of Tailings considering Chemical and Physical Clogging in Lixi Tailings Dam, China Mon, 11 Apr 2016 09:48:34 +0000 http://www.hindawi.com/journals/jchem/2016/8147845/ Chemical and physical clogging frequently occur in tailings dam. The clogging seriously influences the safety of tailings dam. This paper conducts several column experiments to analyse the physical and chemical clogging of the Lixi tailings dam in China. The experiment results of chemical clogging show that average flow velocity and permeability decrease by approximately 50% to 60%. The experiment results of physical clogging show that these values decrease by approximately 50% to 70%. For physical clogging, a higher hydraulic gradient could result in a larger extent of decrease in the permeability coefficient. The permeability did not decrease when the hydraulic gradient was equal to 0.125. The results of chemical clogging column experiments show that ferrous ion solution concentration is disproportional to the permeability coefficient. This scenario can be attributed to the extremely small concentration gradients. Zengguang Xu, Xuemin Yang, Junrui Chai, Yuan Qin, and Yanlong Li Copyright © 2016 Zengguang Xu et al. All rights reserved. Food Chemistry: Food Quality and New Analytical Approaches Sun, 10 Apr 2016 06:46:59 +0000 http://www.hindawi.com/journals/jchem/2016/7296348/ Nivia M. M. Coelho, César R. T. Tarley, Claudia Ruiz-Capillas, Luciana M. Coelho, and Miguel de la Guardia Copyright © 2016 Nivia M. M. Coelho et al. All rights reserved. Experiment and Simulation Study on the Special Phase Behavior of Huachang Near-Critical Condensate Gas Reservoir Fluid Thu, 07 Apr 2016 12:46:56 +0000 http://www.hindawi.com/journals/jchem/2016/2742696/ Due to the special phase behavior of near-critical fluid, the development approaches of near-critical condensate gas and near-critical volatile oil reservoirs differ from conventional oil and gas reservoirs. In the near-critical region, slightly reduced pressure may result in considerable change in gas and liquid composition since a large amount of gas or retrograde condensate liquid is generated. It is of significance to gain insight into the composition variation of near-critical reservoir during the depletion development. In our study, we performed a series of PVT experiments on a real near-critical gas condensate reservoir fluid. In addition to the experimental studies, a commercial simulator combined with the PREOS model was utilized to study retrograde condensate characteristics and reevaporation mechanism of condensate oil with CO2 injection based on vapor-liquid phase equilibrium thermodynamic theory. The research shows that when reservoir pressure drops below a certain pressure, the variation of retrograde condensate liquid saturation of the residual reservoir fluid exhibits the phase behavior of volatile oil. Dali Hou, Yang Xiao, Yi Pan, Lei Sun, and Kai Li Copyright © 2016 Dali Hou et al. All rights reserved. Electron Beam Synthesis and Characterization of Acrylamide/Acrylic Acid Hydrogels Using Trimethylolpropane Trimethacrylate as Cross-Linker Tue, 05 Apr 2016 13:56:28 +0000 http://www.hindawi.com/journals/jchem/2016/1470965/ The purpose of the paper is to present the synthesis and characterization of hydrogels prepared by free-radical copolymerization of acrylamide and acrylic acid in aqueous solutions using potassium persulfate as initiator and trimethylolpropane trimethacrylate as cross-linker, via the radiation technique. The samples were subjected to electron beam treatment in the dose range of 2 to 4 kGy and the influence of the absorbed dose and amount of cross-linker on the swelling properties, diffusion coefficient, and network parameters of hydrogels was investigated. A possible reaction mechanism for acrylamide/acrylic acid/trimethylolpropane trimethacrylate hydrogels was also suggested. The structure and morphology of hydrogels were characterized by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Gabriela Craciun, Elena Manaila, and Maria Daniela Stelescu Copyright © 2016 Gabriela Craciun et al. All rights reserved. The Effects of Controlled Drainage on N Concentration and Loss in Paddy Field Sun, 03 Apr 2016 16:09:34 +0000 http://www.hindawi.com/journals/jchem/2016/1073691/ To relieve the situation of the agricultural nonpoint pollution (NPS) in south and east China, paddy field controlled drainage (PFCD) is applied as an important and efficient approach to agricultural water management. A series of PFCD tests at four major growth stages of rice were conducted by use of 18 lysimeters. Concentration of ammonia nitrogen (-N) and nitrate nitrogen (-N) in surface and subsurface paddy water was observed. The results indicated that the concentration of -N and -N in paddy water declined with the persistence of a waterlogged condition. Compared to traditional drainage, PFCD reduced N loss in surface water by 95.6%, 78.7%, 59.6%, and 87.4% at the stage of tillering, jointing-booting, heading-flowering, and milking, respectively. It should be noted that loads of N losses in surface water increased on the fourth day after waterlogging at the jointing-booting and milking stage, and surface water exhibited higher N concentration on the first day after waterlogging at each stage. Therefore, paddy field surface water drainage should be avoided in these periods. Bin Lu, Guangcheng Shao, Shuang’en Yu, Shiqiang Wu, and Xinghua Xie Copyright © 2016 Bin Lu et al. All rights reserved. Synthesis, Biological, and Quantum Chemical Studies of Zn(II) and Ni(II) Mixed-Ligand Complexes Derived from N,N-Disubstituted Dithiocarbamate and Benzoic Acid Sun, 03 Apr 2016 08:34:12 +0000 http://www.hindawi.com/journals/jchem/2016/5129010/ Some mixed-ligand complexes of Zn(II) and Ni(II) derived from the sodium salt of N-alkyl-N-phenyl dithiocarbamate and benzoic acid have been prepared. The complexes are represented as ZnMDBz, ZnEDBz, NiMDBz, and NiEDBz (MD: N-methyl-N-phenyl dithiocarbamate, ED: N-ethyl-N-phenyl dithiocarbamate, and Bz: benzoate); and their coordination behavior was characterized on the basis of elemental analyses, IR, electronic spectra, magnetic and conductivity measurements, and quantum chemical calculations. The magnetic moment measurement and electronic spectra were in agreement with the four proposed coordinate geometries for nickel and zinc complexes and were corroborated by the theoretical quantum chemical calculations. The quantum chemically derived thermodynamics parameters revealed that the formation of N-methyl-N-phenyl dithiocarbamate complexes is more thermodynamically favourable than that of the N-ethyl-N-phenyl dithiocarbamate complexes. The bioefficacy of the mixed-ligand complexes examined against different microbes showed moderate to high activity against the test microbes. The anti-inflammatory and antioxidant studies of the metal complexes showed that the ethyl substituted dithiocarbamate complexes exhibited better anti-inflammatory and antioxidant properties than the methyl substituted dithiocarbamate complexes. Anthony C. Ekennia, Damian C. Onwudiwe, Aderoju A. Osowole, Lukman O. Olasunkanmi, and Eno E. Ebenso Copyright © 2016 Anthony C. Ekennia et al. All rights reserved. Systematic Reduction of the Detailed Kinetic Mechanism for the Combustion of n-Butane Thu, 31 Mar 2016 18:01:54 +0000 http://www.hindawi.com/journals/jchem/2016/8153582/ A systematic approach for mechanism reduction was demonstrated to generate a skeletal and reduced mechanism for the oxidation of -butane. First, a skeletal mechanism, including 89 species and 440 elementary reactions, was derived from a 230-species detailed mechanism using path flux analysis (PFA). Then, the unimportant reactions were eliminated using the importance index defined in computational singular perturbation (CSP), resulting in a skeletal mechanism consisting of 89 species and 298 elementary reactions. Finally, 20 global quasi-steady-state species were identified using a CSP-based time-scale analysis, leading to a 69-species reduced mechanism. Validation of the 89-species skeletal and 69-species reduced mechanisms showed good agreement with the detailed mechanism for both the ignition delay time and the distribution of species concentration over a wide range of simulation conditions. Chunhui Liu, Zhengxing Zuo, and Huihua Feng Copyright © 2016 Chunhui Liu et al. All rights reserved. Study on Modification of NaX Zeolites: The Cobalt (II)-Exchange Kinetics and Surface Property Changes under Thermal Treatment Thu, 31 Mar 2016 13:04:14 +0000 http://www.hindawi.com/journals/jchem/2016/1789680/ The cobalt (II) ion-exchange process followed the Freundlich and Langmuir adsorption models as well as the pseudo-second-order kinetic model. The cobalt-exchanged contents increased when the initial Co(NO3)2 solution concentration increased up to 0.14 mol L−1 at the optimal pH of 6.05. The N2 adsorption isotherms are mixed types I/II isotherms and H3 type hysteresis. Both the micropore and mesopore adsorptions occurred during the adsorption process. The modification, which is both the cobalt (II) exchange and thermal treatment, significantly improved the surface properties of NaX zeolites. Accordingly, the optimal temperature range is 500 to 600°C for a thermal treatment. This is consistent with the results of XRD analysis. Hoai-Lam Tran, Maw-Suey Kuo, Wein-Duo Yang, and Yu-Chang Huang Copyright © 2016 Hoai-Lam Tran et al. All rights reserved. Environmental Factors and Soil CO2 Emissions in an Alpine Swamp Meadow Ecosystem on the Tibetan Plateau in Response to Experimental Warming Tue, 29 Mar 2016 12:21:35 +0000 http://www.hindawi.com/journals/jchem/2016/2573185/ We examined the response of soil CO2 emissions to warming and environmental control mechanisms in an alpine swamp meadow ecosystem on the Tibetan Plateau. Experimental warming treatments were performed in an alpine swamp meadow ecosystem using two open-top chambers (OTCs) 40 cm (OA) and 80 cm (OB) tall. The results indicate that temperatures were increased by 2.79°C in OA and 4.96°C in OB, that ecosystem CO2 efflux showed remarkable seasonal variations in the control (CK) and the two warming treatments, and that all three systems yielded peak values in August of 123.6, 142.3, and 166.2 g C m−2 month−1. Annual CO2 efflux also showed a gradual upward trend with increased warming: OB (684.1 g C m−2 year−1) > OA (580.7 g C m−2 year−1) > CK (473.3 g C m−2 year−1). Path analysis revealed that the 5 cm depth soil temperature was the most important environmental factor affecting soil CO2 emissions in the three systems. Bin Wang, Ben Niu, Xiaojie Yang, and Song Gu Copyright © 2016 Bin Wang et al. All rights reserved. Hybrid Adsorptive and Oxidative Removal of Natural Organic Matter Using Iron Oxide-Coated Pumice Particles Tue, 29 Mar 2016 07:34:05 +0000 http://www.hindawi.com/journals/jchem/2016/3108034/ The aim of this work was to combine adsorptive and catalytic properties of iron oxide surfaces in a hybrid process using hydrogen peroxide and iron oxide-coated pumice particles to remove natural organic matter (NOM) in water. Experiments were conducted in batch, completely mixed reactors using various original and coated pumice particles. The results showed that both adsorption and catalytic oxidation mechanisms played role in the removal of NOM. The hybrid process was found to be effective in removing NOM from water having a wide range of specific UV absorbance values. Iron oxide surfaces preferentially adsorbed UV280-absorbing NOM fractions. Furthermore, the strong oxidants produced from reactions among iron oxide surfaces and hydrogen peroxide also preferentially oxidized UV280-absorbing NOM fractions. Preloading of iron oxide surfaces with NOM slightly reduced the further NOM removal performance of the hybrid process. Overall, the results suggested that the tested hybrid process may be effective for removal of NOM and control disinfection by-product formation. Sehnaz Sule Kaplan Bekaroglu, Nevzat Ozgu Yigit, Bilgehan Ilker Harman, and Mehmet Kitis Copyright © 2016 Sehnaz Sule Kaplan Bekaroglu et al. All rights reserved. Phenolic Compounds, Antioxidant Activity, and Other Characteristics of Extra Virgin Olive Oils from Italian Autochthonous Varieties Tonda di Villacidro, Tonda di Cagliari, Semidana, and Bosana Mon, 28 Mar 2016 12:07:59 +0000 http://www.hindawi.com/journals/jchem/2016/8462741/ Extra virgin olive oils (EVOOs) from the fruits of Italian autochthonous varieties Tonda di Villacidro, Tonda di Cagliari, Semidana, and Bosana were investigated to promote their quality aspects. All the analyzed EVOOs showed low values of acidity (≤0.45%) and of peroxide value (≤6.22 mEq O2/kg). There were no relevant differences in fatty acids and triacylglycerols composition among the four EVOOs. Tocopherols determined by HPLC-FL revealed that Bosana oil was characterized by the highest -tocopherol level (213.3 ± 55.4 mg/kg). Chlorophylls, carotenoids, and total phenol (TP) contents as well as antioxidant activity (FRAP, DPPH∙, and ABTS∙+ assays) of the oils hydrophilic fractions (HFs) were assessed by spectrophotometric methods. Some differences concerning the antioxidant activity and the TP content were observed: Bosana oil HF activity was the most pronounced (1.17 ± 0.37 mmol TEAC/kg) and it contained the highest TPs amount (335.20 ± 121.34 mg/kg). HFs phenolic composition was determined by HPLC-DAD. The main identified phenols were secoiridoids, dominating in Bosana oil, such as decarboxymethyl ligstroside aglycone (p-HPEA-EDA, 35.8 ± 19.9 mg/kg) and oleuropein aglycone (3,4-HPEA-EA up to 84.7 mg/kg). In summary, all the four varieties showed good characteristics for the use as quality EVOO. Carlo I. G. Tuberoso, Igor Jerković, Marialuce Maldini, and Gabriele Serreli Copyright © 2016 Carlo I. G. Tuberoso et al. All rights reserved. Spectroscopic, Electrochemical, and In Silico Characterization of Complex Formed between 2-Ferrocenylbenzoic Acid and DNA Mon, 28 Mar 2016 11:34:55 +0000 http://www.hindawi.com/journals/jchem/2016/7468951/ We present the synthesis of 2-ferrocenylbenzoic acid (FcOH) and its electrochemical and spectroscopic characterization. FcOH was characterized for interaction with DNA using theoretical and experimental methods. UV-visible spectroscopy and cyclic voltammeter (CV) were used for the experimental account of FcOH-DNA complex. The experimental results showed that the FcOH interacts by electrostatic mode. The binding constant () and Gibbs free energy () for the FcOH-DNA complex have been estimated as 5.3 × 104 M−1 and −6.44 kcal/mol, respectively. The theoretical DNA binding of FcOH was studied with AutoDock molecular docking software. The docking studies yield good approximation with experimental data and explain the sites of binding. Ataf Ali Altaf, Bhajan Lal, Nasir Khan, Amin Badshah, Shafiq Ullah, and Kamran Akbar Copyright © 2016 Ataf Ali Altaf et al. All rights reserved.