Journal of Chemistry http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Natural Enrichment of Trace Elements in Surface Horizons of Calcareous Soils (La Mancha, Spain) Tue, 31 Mar 2015 10:25:23 +0000 http://www.hindawi.com/journals/jchem/2015/606837/ The study of five soil profiles developed on carbonatic sediments of Tertiary Miocene origin has been carried out. The topography of the area was basically flat and the traditional uses of the soils are the cultivation of dry cereals and grapevine. The geochemical characterization of the aforementioned profiles involves a study of the contents of major and trace elements among other pedologic aspects (texture, pH, organic matter, etc.). The results of this study also indicate a superficial enrichment of trace elements due to the leaching of Ca and moderate biological and anthropic activity. We can consider strontium, Sr, as the trace element that characterizes these limy soils (435 mg/kg average content in total soil and 708 mg/kg in the original rock). These contents are similar to the average value in Castilla-La Mancha of 380 mg/kg and are higher than the average in world soils of about 200 mg/kg. High levels of dangerous or pollutant elements (Cd, Hg, Pb, Cu, Zn, or Ni) were not detected. The majority of trace element anomalies are related to calcareous material and the leaching of calcium carbonate (Ca), while the influence of the anthropogenic factor is secondary. Soil quality does not indicate toxicity although surficial enrichment suggests a weak threat from consuming crops. Sandra Bravo Martín-Consuegra, Jose A. Amorós Ortíz-Villajos, Caridad Pérez-de-los-Reyes, Francisco J. García Navarro, Rolando Ruedas Luna, and Raimundo Jiménez Ballesta Copyright © 2015 Sandra Bravo Martín-Consuegra et al. All rights reserved. Adsorption of Carbon Dioxide onto Activated Carbon Prepared from Coconut Shells Tue, 31 Mar 2015 09:18:54 +0000 http://www.hindawi.com/journals/jchem/2015/106590/ This study presents the fabrication of high-quality activated carbon (AC) from discarded coconut shells. The effects of experimental parameters such as activation temperature and activation time on the basic characteristics of AC, including charcoal yield, ash content, pH value, Brunauer-Emmett-Teller (BET) specific surface area, total pore volume, and iodine adsorption, are investigated. The results indicate that as the activation temperature and activation time increase, the charcoal yield of the AC decreases. In contrast, iodine adsorption, ash content, pH value, and total pore volume increase with activation temperature. The AC sample activated at 1000°C for 120 min had the highest BET specific surface area and total pore volume and thus the best CO2 adsorption performance. This sample was compared with 30-mesh commercial AC. The results reveal that coconut-based AC has better instantaneous adsorption capabilities. Pei-Hsing Huang, Hao-Hsiang Cheng, and Sheau-Horng Lin Copyright © 2015 Pei-Hsing Huang et al. All rights reserved. The HPLC Fingerprint and Isovanillin Content of Benincasa hispida Seeds Mon, 30 Mar 2015 13:32:06 +0000 http://www.hindawi.com/journals/jchem/2015/629302/ The Benincasa hispida seed is used as traditional Chinese medicine (TCM). However, there is still a lack of medicinal quality control of B. hispida seeds. The seeds may contain isovanillin, but this finding remains to be confirmed and quantified. The current study aimed to confirm the existence of isovanillin and then preliminarily establish medicinal quality standards for B. hispida seeds. Fourteen batches of unilateral and bilateral B. hispida seeds were purchased from 7 different producers in China. Semipreparative high-performance liquid chromatography (HPLC) was used to isolate and purify the isovanillin from B. hispida seeds. Its chemical structure was elucidated by UV, 1H-NMR, IR spectroscopy, and GC-MS. The B. hispida seed fingerprint and isovanillin determination were performed on an HPLC instrument. Data obtained from the unilateral and bilateral specimens were analyzed with a similarity evaluation system. The HPLC fingerprint showed 19 characteristic peaks with high similarity between the unilateral and bilateral B. hispida seeds. The isovanillin content among the fourteen batches ranged from 13.46 to 46.80 μg/g. The results of this study may provide a preliminary reference for the quality control of B. hispida seeds. Jing Liu, Pinglin Li, Qi Wang, Bin Li, and Guoqiang Li Copyright © 2015 Jing Liu et al. All rights reserved. Inhibitory Effect of Natural Phenolic Compounds on Aspergillus parasiticus Growth Mon, 30 Mar 2015 10:51:54 +0000 http://www.hindawi.com/journals/jchem/2015/547925/ Considering the impact of Aspergillus species on crops, it appears to be highly desirable to apply strategies to prevent their growth, as well as to eliminate or reduce their presence in food products. For this reason, the aims of this investigation were to evaluate the effects of ten natural phenolic compounds on the Aspergillus parasiticus growth and to determine which physicochemical properties are involved in the antifungal activity. According to the results of minimum inhibitory concentration (MIC) values of the individual compounds, isoeugenol, carvacrol, and thymol were the most active phenolic components (1.26 mM, 1.47 mM, and 1.50 mM, resp.), followed by eugenol (2.23 mM). On the other hand, creosol, p-cresol, o-cresol, m-cresol, vanillin, and phenol had no effects on fungal development. Logarithm of the octanol/water partition coefficient (log P), refractivity index (RI), and molar volume (MV) were demonstrated to be the descriptors that best explained the antifungal activity correlated to lipophilicity, reactivity of the components, and steric aspect. These findings make an important contribution to the search for new compounds with antifungal activity. Romina P. Pizzolitto, Carla L. Barberis, José S. Dambolena, Jimena M. Herrera, María P. Zunino, Carina E. Magnoli, Héctor R. Rubinstein, Julio A. Zygadlo, and Ana M. Dalcero Copyright © 2015 Romina P. Pizzolitto et al. All rights reserved. Preparation of Na2Ti3O7/Titanium Peroxide Composites and Their Adsorption Property on Cationic Dyes Mon, 30 Mar 2015 09:39:32 +0000 http://www.hindawi.com/journals/jchem/2015/363405/ Na2Ti3O7/titanium peroxide composites (TN-TP) were successfully prepared with the reaction of Ti foils, NaOH, and H2O2 at 60°C for 24 h in water bath. The Na2Ti3O7 appeared as nanorods in composites. Water bath temperature, water bath time, and the concentration of H2O2 and NaOH were crucial. The reaction mechanism was proposed. TN-TP was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric and differential scanning calorimetry (TG-DSC). TN-TP was a mesoporous material and exhibited stronger adsorption capability for neutral red (NR), malachite green (MG), methylene blue (MB), and crystal violet (CV) than pure Na2Ti3O7 and pure titanium peroxide, and the saturated adsorption capacities were 490.21, 386.13, 322.81, and 292.74 mg/g at 25°C, respectively. It was found that the pseudo-second-order kinetic model and the Langmuir model could well describe the adsorption kinetic and isotherm of cationic dyes studied. The results of this work are of great significance for environmental applications of TN-TP as a promising adsorbent material for dyeing water purification. Meixia Zhao, Jiguo Huang, Xueting Guo, Haitao Chen, Hai Zhao, Lili Dong, and Xing-juan Liu Copyright © 2015 Meixia Zhao et al. All rights reserved. Effect of Semiarid Environment on Some Nutritional and Antinutritional Attributes of Calendula (Calendula officinalis) Sun, 29 Mar 2015 14:29:55 +0000 http://www.hindawi.com/journals/jchem/2015/318506/ Stressful environments have been shown to affect the metabolism in some plants. In the present study, we assessed whether semiarid environment (saline and saline alkaline soil) could affect the nutritional (total proteins, phenolics and riboflavin contents, and catalase activity) and antinutritional (hydrogen peroxide and malondialdehyde contents) properties differently in different plant parts (leaves, flowers, and roots) of calendula. Although salinity decreased plant biomass, it did not affect total protein and phenolics contents in the calendula. All plant parts were rich in riboflavin contents. However, plants grown under saline-alkali soil had relatively more riboflavin contents in the flowers. Salinity increased hydrogen peroxide (H2O2) concentration in the flowers and roots, whereas saline-alkali soil did not affect it. Plants exposed to both saline and saline-alkali soil had greater catalase activity in the flowers and leaves. Plants exposed to salinity had higher malondialdehyde (MDA) contents in the flowers compared with nonsaline and saline-alkali conditions. Nonetheless, the possibility of safely using different parts of calendula as nutraceutical was in the order flower > root > leaf. Overall, the results suggested that plant can be grown in mild saline-alkali (EC ≤ 7; pH = 8.5) soils without affecting its nutraceutical properties. Muhammad Iqbal, Iqbal Hussain, Asma Habib, Muhammad Arslan Ashraf, and Rizwan Rasheed Copyright © 2015 Muhammad Iqbal et al. All rights reserved. Microbial Degradation of Indole and Its Derivatives Sun, 29 Mar 2015 13:39:21 +0000 http://www.hindawi.com/journals/jchem/2015/129159/ Indole and its derivatives, including 3-methylindole and 4-chloroindole, are environmental pollutants that are present worldwide. Microbial degradation of indole and its derivatives can occur in several aerobic and anaerobic pathways; these pathways involve different known and characterized genes. In this minireview, we summarize and explain the microbial degradation of indole, indole-3-acetic acid, 4-chloroindole, and methylindole. Pankaj Kumar Arora, Ashutosh Sharma, and Hanhong Bae Copyright © 2015 Pankaj Kumar Arora et al. All rights reserved. Synthesis and Characterization of Novel Copolymeric Resveratrol Conjugates Sun, 29 Mar 2015 13:38:23 +0000 http://www.hindawi.com/journals/jchem/2015/245625/ Resveratrol (RSV), naturally found in plants, is known to have health benefits and has been proposed as a potential anticancer and cardioprotective drug. However, due to its molecular structure, it undergoes rapid metabolism in the body resulting in low bioavailability. Novel polymeric methoxy-poly(ethylene glycol)-block-poly(ε-caprolactone) (mPEG-PCL) RSV conjugates with varying PCL chain lengths have been synthesised and formulated into micelles and/or nanoparticles for preliminary in vitro stability studies. RSV conjugated with mPEG2000-PCL9500 was found to have improved solubility and stability of RSV as compared to RSV alone. The length of the PCL chain was found to affect the micelle formation, hence the stability in physiological buffers and rat plasma. Yan-Jing Ng, Heather A. E. Benson, David H. Brown, and Yan Chen Copyright © 2015 Yan-Jing Ng et al. All rights reserved. Nitrate Adsorption on Clay Kaolin: Batch Tests Sun, 29 Mar 2015 09:37:08 +0000 http://www.hindawi.com/journals/jchem/2015/397069/ Soils possessing kaolin, gibbsite, goethite, and hematite particles have been found to have a natural capacity to attenuate pollution in aqueous phase. On the other hand, the hydroxyl group in soil increases anion exchange capacity under a low pH condition. The main objective of this paper was to evaluate effects of kaolin on nitrate reduction under acidic condition. In order to analyze the kaolin adsorption behaviour under various conditions, four different concentrations of nitrate, 45, 112.5, 225, and 450 , with a constant pH equal to 2, constant temperature equal to 25°C, and exposure period varying from 0 to 150 minutes were considered. The capacity of nitrate adsorption on kaolin has also been studied involving two well-known adsorption isotherm models, namely, Freundlich and Longmuir. The results revealed that approximately 25% of the nitrate present in the solution was adsorbed on clay kaolin. The laboratory experimental data revealed that Freundlich adsorption isotherm model was more accurate than Longmuir adsorption model in predicting of nitrate adsorption. Furthermore, the retardation factor of nitrate pollution in saturated zone has been found to be approximately 4 in presence of kaolin, which indicated that kaolin can be used for natural scavenger of pollution in the environment. Morteza Mohsenipour, Shamsuddin Shahid, and Kumars Ebrahimi Copyright © 2015 Morteza Mohsenipour et al. All rights reserved. Polyphenolic Profile of Maize Seedlings Treated with 24-Epibrassinolide Sun, 29 Mar 2015 08:52:44 +0000 http://www.hindawi.com/journals/jchem/2015/976971/ High-performance thin-layer chromatography (HPTLC) combined with image analysis and pattern recognition methods were used for fingerprinting of phenolic compounds present in seedlings of two maize genotypes ZP 434 (new generation hybrid, drought tolerant) and ZP 704 (older generation hybrid, drought sensitive) treated with different concentrations of 24-epibrassinolide. This is the first report of TLC chromatographic profile of phenolics’ mixtures in maize seed extracts influenced by brassinosteroid phytohormones. Nine samples of shoot of seedlings for the whole concentration range of phytohormones (5.2 × 10−7–5.2 × 10−15 M), one sample of root of seedlings treated with 5.2 × 10−15 M 24-epibrassinolide, and the control samples of nontreated seedlings, for both genotypes, were analyzed. Phenolic profiles of root extracts indicate the absence of more polar compounds such as phenolic acids and glycosides present in shoot of seedlings. Also, hormones applied in higher concentrations have an inhibiting effect on the content of phenolics in ZP 434. Application of chemometric methods enables characterization of particular genotype of maize according to its phenolic profile. Hadi Waisi, Aleksandra Kosović, Đurđa Krstić, Dušanka Milojković-Opsenica, Bogdan Nikolić, Vesna Dragičević, and Jelena Trifković Copyright © 2015 Hadi Waisi et al. All rights reserved. Ionic Conductance, Thermal and Morphological Behavior of PEO-Graphene Oxide-Salts Composites Sun, 29 Mar 2015 08:21:42 +0000 http://www.hindawi.com/journals/jchem/2015/695930/ Thin films composites of poly(ethylene oxide)-graphene oxide were fabricated with and without lithium salts by solvent cast method. The ionic conductivity of these composites was studied at various concentrations of salt polymer-GO complexes and at different temperatures. The effects of temperature and graphene oxide concentration were measured from Arrhenius conductance plots. It is shown that the addition of salts in pure PEO increases conductance many times. The graphene oxide addition has enhanced the conductance approximately 1000 times as compared to that of pure PEO. The activation energies were determined for all the systems which gave higher values for pure PEO and the value decreased with the addition of LiClO4 and LiCl salts and further decreases with the addition of graphene oxide. The composite has also lowered the activation energy values which mean that incorporation of GO in PEO has decreased crystallinity and the amorphous region has increased the local mobility of polymer chains resulting in lower activation energies. SEM analysis shows uniform distribution of GO in polymer matrix. The thermal stability studies reveal that incorporation of GO has somewhat enhanced the thermal stability of the films. Mohammad Saleem Khan and Abdul Shakoor Copyright © 2015 Mohammad Saleem Khan and Abdul Shakoor. All rights reserved. Binding Mode Investigation of Polyphenols from Scrophularia Targeting Human Aldose Reductase Using Molecular Docking and Molecular Dynamics Simulations Sun, 29 Mar 2015 08:04:49 +0000 http://www.hindawi.com/journals/jchem/2015/434256/ Aldose reductase (ALR2), a vital enzyme involved in polyol pathway, has befitted as a novel drug target in antidiabetes drug discovery process. In the present study, the binding mode and pharmacokinetic properties of potential polyphenolic compounds with reported aldose reductase inhibitory activity from the genus Scrophularia have been investigated. The human ALR2 enzyme (PDB ID: 2FZD) acted as the receptor in the current study. Among the compounds investigated, acacetin, a methoxy flavonoid, displayed the stable binding to the active site of ALR2 with least binding energy value. Molecular interaction analysis revealed that acacetin interrupts the proton donation mechanism, necessary for the catalytic activity of ALR2, by forming H-bond with Tyr48 (proton donor). In addition, acacetin also possessed favorable ADME properties and complies with Lipinski’s rule of 5 representing the possible drug-like nature compared to other polyphenols. Interestingly, the biological activity predictions also ranked acacetin with higher probability score for aldose reductase inhibition activity. Moreover, the molecular dynamics simulation of ALR2-acacetin complex was validated for the stability of ligand binding and the refined complex was used for generation of receptor-ligand pharmacophore model. Thus, the molecular insights of receptor-ligand interactions gained from the present study can be utilized for the development of novel aldose reductase inhibitors from Scrophularia. Abinaya Manivannan, Prabhakaran Soundararajan, Yoo Gyeong Park, Sugunadevi Sakkiah, and Byoung Ryong Jeong Copyright © 2015 Abinaya Manivannan et al. All rights reserved. Evaluation of Heavy Metals Contamination from Environment to Food Matrix by TXRF: The Case of Rice and Rice Husk Sun, 29 Mar 2015 07:46:56 +0000 http://www.hindawi.com/journals/jchem/2015/274340/ This paper is devoted to the chemical analysis of contaminated soils of India and the rice grown in the same area. Total reflection X-ray fluorescence spectroscopy is a well-established technique for elemental chemical analysis of environmental samples, and it can be a useful tool to assess food safety. Metals uptake in rice crop grown in soils from different areas was studied. In this work soil, rice husk and rice samples were analyzed after complete solubilization of samples by microwave acid digestion. Heavy metals concentration detected in rice samples decreases in the following order: Mn > Zn > Cu > Ni > Pb > Cr. The metal content in rice husk was higher than in rice. This study suggests, for the first time, a possible role of heavy metals filter played by rice husk. The knowledge of metals sequestration capability of rice husk may promote some new management practices for rice cultivation to preserve it from pollution. Fabjola Bilo, Marco Lodolo, Laura Borgese, Alberto Bosio, Laura Benassi, Laura Eleonora Depero, and Elza Bontempi Copyright © 2015 Fabjola Bilo et al. All rights reserved. Traceability of PDO Olive Oil “Terra di Bari” Using High Resolution Melting Sun, 29 Mar 2015 06:38:48 +0000 http://www.hindawi.com/journals/jchem/2015/496986/ The aim of the research was to verify the applicability of microsatellite (SSR) markers in High Resolution Melting (HRM) analysis for the identification of the olive cultivars used in the “Terra di Bari” PDO extra virgin olive oil. A panel of nine cultivars, widespread in Apulia region, was tested with seventeen SSR primer pairs and the PCR products were at first analysed with a Genetic Analyzer automatic sequencer. An identification key was obtained for the nine cultivars, which showed an unambiguous discrimination among the varieties constituting the “Terra di Bari” PDO extra virgin olive oil: Cima di Bitonto, Coratina, and Ogliarola. Subsequently, an SSR based method was set up with the DCA18 marker, coupled with HRM analysis for the distinction of the Terra di Bari olive oil from non-Terra di Bari olive oil using different mixtures. Thus, this analysis enabled the distinction and identification of the PDO mixtures. Hence, this assay provided a flexible, cost-effective, and closed-tube microsatellite genotyping method, well suited to varietal identification and authentication analysis in olive oil. Cinzia Montemurro, Monica Marilena Miazzi, Antonella Pasqualone, Valentina Fanelli, Wilma Sabetta, and Valentina di Rienzo Copyright © 2015 Cinzia Montemurro et al. All rights reserved. Comparison of the Usefulness of SPE Cartridges for the Determination of β-Blockers and β-Agonists (Basic Drugs) in Environmental Aqueous Samples Thu, 26 Mar 2015 14:19:39 +0000 http://www.hindawi.com/journals/jchem/2015/195280/ Even though the methodology used for the determination of β-blockers and β-agonists in environmental samples is based mainly on solid-phase extraction (SPE) and gas chromatography or liquid chromatography with mass spectrometric detection, the available literature data on the applied SPE procedures is rather sparse. In this paper such comparison is presented. Moreover, the usefulness of the eight SPE cartridges for the determination of five β-blockers (acebutolol, atenolol, metoprolol, nadolol, and propranolol) and two β-agonists (salbutamol and terbutaline) in environmental aqueous samples using GC techniques is tested. Among them, three (the trifunction sorbent Strata Screen C, the copolymers LiChrolut EN, and the functionalized copolymer Isolute ENV+) were used for the first time for this purpose. It was confirmed that polystyrene-divinylbenzene-N-vinylpyrrolidone copolymers (PS-DVB-VP, Strata-X, and Oasis HLB cartridges) have a better potential than a cation-exchange sorbent for the extraction of the target drugs from environmental water samples. However, it should be stressed out that the direct application of the tested SPE conditions for the analysis of real environmental water samples is not possible, and such parameters, like volume of loading sample, appropriate solvents for washing and elution steps, and so forth, must be optimized again in order to achieve satisfactory recovery values for the target compounds. Magda Caban, Piotr Stepnowski, Marek Kwiatkowski, Joanna Maszkowska, Marta Wagil, and Jolanta Kumirska Copyright © 2015 Magda Caban et al. All rights reserved. In Vitro Antitumor Activity of a Keggin Vanadium-Substituted Polyoxomolybdate and Its ctDNA Binding Properties Thu, 26 Mar 2015 13:58:17 +0000 http://www.hindawi.com/journals/jchem/2015/753751/ A Keggin vanadium-substituted polyoxomolybdate, K5PMo10V2O40 (PMo10V2), has been synthesized and it’s antitumor effect against Hela cells was investigated. The calf thymus DNA (ctDNA) binding ability of PMo10V2 was also evaluated by UV-Vis absorption spectra and fluorescence spectra. The identity and high purity of PMo10V2 was confirmed by elemental analysis and IR analysis. And the antitumor activity test of PMo10V2 was carried out on Hela cancer cells line by MTT assay. The results of MTT assay show that PMo10V2 significantly reduced the viability of Hela cells in a dose-dependent manner and exhibited stronger inhibitory activity against Hela cells at an IC50 of 800 μg/mL, which is more effective than the positive control, 5-Fu . The results of the UV-Vis absorption spectra and fluorescence spectra indicated the groove or outside stacking binding between PMo10V2 and ctDNA. These results show that the antitumor activity of PMo10V2 may be caused by the interactions between DNA and PMo10V2. Wen Qi, Ying Qin, Yanfei Qi, Li Guo, and Juan Li Copyright © 2015 Wen Qi et al. All rights reserved. Oleophobic Modification of Hollow Glass Microspheres and Its Effect on the Foaming Capacity and Stability of Foam Extinguishing Agent Thu, 26 Mar 2015 12:24:49 +0000 http://www.hindawi.com/journals/jchem/2015/923894/ We utilized tridecafluorooctyltriethoxysilane (F8261) for the surface modification of hollow glass microspheres (HGM). We then measured the contact angles and the residing time of oil droplets on the HGM surface under different conditions and investigated the effects of the modifier concentration, reaction time and reaction temperature, and other factors on the outcomes of the modification reaction. We also compared the effects of HGM on the expansion ratio and 25% drainage time of protein foam liquid before and after the modification treatment and investigated the effects of HGM surface oleophobic modification on the foaming capacity and stability of foam extinguishing agent. The results showed that when the F8261 concentration was 1.0%, the temperature was 60°C, and the ultrasound treatment time was 2.0 h, the contact angle was up to 132.5°, the oleophobic property of HGM could be significantly enhanced, and the foaming capacity and the oil surface stability were significantly improved by the oleophobic modification. Baohua Tang and Zhaoliang Wu Copyright © 2015 Baohua Tang and Zhaoliang Wu. All rights reserved. Preliminary Investigation concerning Metals Bioavailability in Waters of Aries River Catchment by Using the Diffusive Gradients in Thin Films Technique Thu, 26 Mar 2015 09:26:39 +0000 http://www.hindawi.com/journals/jchem/2015/762121/ The paper presents the metals content and bioavailability in waters of Aries River catchment, Romania. Concentration of labile dissolved metal species measured by diffusive gradients in thin films technique (DGT), metals in colloidal and in particulate phases, and also general physical-chemical indicators of water were determined. Very high total metal concentrations were found in the tributaries that drain the mining areas. However, the influence of the polluted tributaries on the Aries River water quality was moderate, as a consequence of the tributaries low flow rate compared with that of the Aries River. Using the DGT technique the bioavailable metals fractions expressed as % of total dissolved metals concentrations were found to be 28–88% for Cu, 43–72% for Zn, 73–85% for Fe, and 33–70% for Mn. Depending on the used method for dissolved metals determination the classification of waters according to quality classes may differ. Excluding the colloidal metal fractions, DGT measures only truly dissolved metal concentrations. In cases with very high metal contamination the differences between total dissolved and DGT-labile concentrations are unimportant for waters classification. However, where the metals concentration is near the thresholds values the determination method is very important. Marin Senila, Erika Andrea Levei, Lacrimioara Ramona Senila, and Marius Roman Copyright © 2015 Marin Senila et al. All rights reserved. Study of Flow-Assisted Corrosion of AZ91D Magnesium Alloy in Loop System Based on Array Electrode Technology Thu, 26 Mar 2015 08:17:20 +0000 http://www.hindawi.com/journals/jchem/2015/596740/ A loop system was used to investigate flow-assisted corrosion (FAC) of AZ91D magnesium alloy at an elbow based on array electrode technology by potentiodynamic polarization, computational fluid dynamics, simulation and surface analysis. The experimental results demonstrate the fluid hydrodynamics plays a significant role in the FAC of AZ91D magnesium alloy. The corrosion rate increases from the outer wall to the inner wall of the elbow, with the higher corrosion rate corresponding to the higher flow velocity and larger shear stress at the elbow. The maximum corrosion rate appears at the innermost wall of the elbow, the location with the maximum flow velocity and shear stress. Hualiang Huang, Guoan Zhang, Jiakuan Yang, Zhiquan Pan, and Xingpeng Guo Copyright © 2015 Hualiang Huang et al. All rights reserved. Detection of T91 Steel Corrosion with a Fe3+-Enhanced Fluorescence Probe Thu, 26 Mar 2015 08:09:11 +0000 http://www.hindawi.com/journals/jchem/2015/654802/ We study a rhodamine-based fluorescent compound (FD2) as corrosion indicator for T91 steel in 3% NaCl solution. FD2 has a desirable property of “turn-on” fluorescence emission via forming a complex with Fe3+ ions. The varying of fluorescence intensity is linked to that of weight-loss of T91 steel. Early attack on T91 steel was detected using fluorescence microscopy. This nondestructive method of initial corrosion detection can be used during maintenance before serious damage happens. Tie Feng Xia, Li Zhang, Da Quan Zhang, and Li Xin Gao Copyright © 2015 Tie Feng Xia et al. All rights reserved. Dissipation and Residues of Thiram in Potato and Soil Thu, 26 Mar 2015 07:16:39 +0000 http://www.hindawi.com/journals/jchem/2015/623847/ The residue levels of thiram during potato cultivation in open field were evaluated. Thiram residues were determined by methylation derivation method with high performance liquid chromatography (HPLC). Wettable powder (WP) formulation containing 25% thiram was applied at 2320 g active gradient hm−2 (a.i. hm−2) dosage for the dissipation study. The decline rate in potato leave and soil followed first-order kinetics equation, and the half-life ranged from 2.8 to 5.4 days and 2.6 to 9.9 days, respectively. In terminal residue, the thiram was sprayed at 580 g a.i. hm−2 (low concentration, recommended dosage) and 1160 g a.i. hm−2 (high concentration, double of recommended dosage). The residues of thiram in potato and soil samples collected in the field at preharvest interval of 21 days and 30 days were all below 0.02 mg kg−1. The results show that thiram possesses low dietary risk in potato at harvest according to supervised residue field trial. It may be safe when used at recommended rate of application. Shaowen Liu, Aijuan Bai, Li Zhou, Chuanshan Yu, Yanjie Li, Sufang Fan, and Canping Pan Copyright © 2015 Shaowen Liu et al. All rights reserved. Aromaticities of Five Membered Heterocycles through Dimethyldihydropyrenes Probe by Magnetic and Geometric Criteria Wed, 25 Mar 2015 10:12:55 +0000 http://www.hindawi.com/journals/jchem/2015/456961/ Aromaticities of five membered heterocycles, containing up to three heteroatoms, are quantified through the dimethyldihydropyrene (DHP) probe. Bond fixation caused by the fusion of heterocycles to the dimethyldihydropyrene nucleus (DHPN) was measured by changes in the 1H NMR chemical shifts (magnetic) and bond lengths alterations (structural criterion). Chemical shifts of dihydropyrenes were calculated at GIAO HF/6-31G(d)//B3LYP/6-31+G(d). For 1H NMR chemical shift analysis, two nonaromatic reference models are studied. Among the studied heterocycles, pyrazole and triazole are about 80–85% aromatic relative to benzene, through both magnetic and geometric criteria. Thiazole and oxazoles are found least aromatic where quantitative estimates of aromaticities are about 34–42%, relative to benzene. These quantitative estimates of aromaticities of five membered heterocycles are also comparable to those from aromatic stabilization energies. The quantification of aromaticity through energetic, magnetic, and structural criteria can deliver the similar inferences provided that suitable reference systems are chosen. Maria and Khurshid Ayub Copyright © 2015 Maria and Khurshid Ayub. All rights reserved. Immobilization of Cd, Zn, and Pb from Soil Treated by Limestone with Variation of pH Using a Column Test Wed, 25 Mar 2015 06:55:38 +0000 http://www.hindawi.com/journals/jchem/2015/641415/ Decades of mining in South Korea have resulted in the contamination of large amounts of soil by metals. The most feasible approach to site restoration requires the use of a stabilization agent to reduce metal mobility. This study examined the leaching characteristics of limestone used as a stabilization agent when subjected to solutions of differing pH. In a laboratory-scale column test, solutions with pH values of 3.5, 4.6, and 5.6, representing acidic to nonacidic rainfall, were applied to soil mixed with limestone. Test results indicate that metal components can be released with the addition of acidic solutions, even if the soil is highly alkaline. Cd and Zn, in particular, exhibited abrupt or continuous leaching when exposed to acid solutions, indicating the potential for contamination of water systems as metal-laden soils are exposed to the slightly acidic rainfall typical of South Korea. Treatment using stabilization agents such as limestone may reduce leaching of metals from the contaminated soil. Stabilizing metal-contaminated farmland is an economical and feasible way to reduce pollutants around abandoned metal mines. Sung-Wook Yun and Chan Yu Copyright © 2015 Sung-Wook Yun and Chan Yu. All rights reserved. Synthesis and Characterization of Cellulose from Green Bamboo by Chemical Treatment with Mechanical Process Tue, 24 Mar 2015 13:10:43 +0000 http://www.hindawi.com/journals/jchem/2015/212158/ Bamboo cellulose was prepared by chemical process involving dewaxing, delignification, and mercerization process. Four samples namely, green bamboo fiber (GBF), dewaxed bamboo fiber (DBF), delignified bamboo fiber (DLBF), and cellulose fiber (CF) had been analysed. FTIR and TGA analysis confirmed the removal of hemicellulose and lignin at the end stage of the process. FTIR results reveal that the D-cellulose OH group occurred at 1639 cm−1 region. SEM micrograph showed that mercerization leads to fibrillation and breakage of the fiber into smaller pieces which promote the effective surface area available for contact. Barrer, Joiyner, and Halenda (BJH) method confirmed that the effective surface area of CF is two times larger compared to GBF. CF showed the highest activation energy compared to GBF. It indicates that CF was thermally stable. Fui Kiew Liew, Sinin Hamdan, Md. Rezaur Rahman, Mohamad Rusop, Josephine Chang Hui Lai, Md. Faruk Hossen, and Md. Mizanur Rahman Copyright © 2015 Fui Kiew Liew et al. All rights reserved. Separation of Organic and Inorganic Compounds for Specific Applications Tue, 24 Mar 2015 13:09:22 +0000 http://www.hindawi.com/journals/jchem/2015/698259/ Hasan Uslu, Dragomir Yankov, Kailas L. Wasewar, Saeid Azizian, Najeeb Ullah, and Waqar Ahmad Copyright © 2015 Hasan Uslu et al. All rights reserved. Structural Characterisation of Asphaltenes during Residue Hydrotreatment with Light Cycle Oil as an Additive Tue, 24 Mar 2015 12:54:00 +0000 http://www.hindawi.com/journals/jchem/2015/580950/ Several atmospheric residues (AR) of Kuwaiti crude, in the absence, or in the presence, of light cycle oil (LCO) as an aromatic additive, were hydrotreated in an experimental plant. Asphaltenes (precipitated from Kuwaiti AR, a hydrotreated AR, and a hydrotreated blend of AR and LCO) were characterised by chemical structure and changes during residue hydrotreatment. The average structural parameters of these asphaltenes, obtained from a combined method of element analysis, average molecular weight, X-ray diffraction, and NMR, demonstrate that, after hydrotreatment, the aromatic cores of the asphaltenes become more compact and smaller whereas the peripheral alkyl branches are decreased in number and shortened. The influence of LCO on residue hydrotreating is also studied in terms of structural changes in the asphaltenes. The findings imply that LCO added to AR during hydrotreating improves the degree of aromatic substitution, the total hydrogen/carbon atomic ratio per average molecule, the distance between aromatic sheets and aliphatic chains, and so forth, by modifying the colloidal nature and microstructure of asphaltene: this is beneficial for the further hydroprocessing of AR. Three hypothetical average molecules are proposed to represent the changes undergone by such asphaltenes during hydrotreatment as well as the effects of additive LCO. Yong-Jun Liu and Zhi-Feng Li Copyright © 2015 Yong-Jun Liu and Zhi-Feng Li. All rights reserved. High Nitrogen Fertilization of Tobacco Crop in Headwater Watershed Contaminates Subsurface and Well Waters with Nitrate Tue, 24 Mar 2015 11:55:06 +0000 http://www.hindawi.com/journals/jchem/2015/375092/ Our hypothesis was that subsurface and well waters in watershed with shallow, stony soils, steep landscapes, and cropped to tobacco are contaminated by nitrate. Nitrate in soil solution was monitored in (0.20 m) and below (0.5 m) root zone with tension lysimeters, in five transects. Water from two wells (beneath tobacco field and in native forest) used for human consumption was also analyzed for nitrate. Soil bulk density, porosity, and saturated hydraulic conductivity were evaluated. Soil physical and hydrological properties showed great variation at different landscape positions and soil depths. Soil coarse grain size, high porosity, and saturated hydraulic conductivity favored leaching nitrate. Nitrate in soil solution from tobacco fields was greater than in natural environment. Nitrate reached depths bellow rooting zone with values as high as 80 mg L−1 in tobacco plantation. Water well located below tobacco plantation had high nitrate concentration, sometimes above the critical limit of 10 mg L−1. Tobacco cropping causes significant water pollution by nitrate, posing risk to human health. A large amount of nitrogen fertilizers applied to tobacco and nitrate in subsurface waters demonstrate the unsustainability of tobacco production in small farming units on steeps slopes, with stony and shallow soils. D. R. Kaiser, L. Sequinatto, D. J. Reinert, J. M. Reichert, D. S. Rheinheimer, and L. Dalbianco Copyright © 2015 D. R. Kaiser et al. All rights reserved. Characteristics, Phytochemical Analysis and Biological Activities of Extracts from Tunisian Chetoui Olea europaea Variety Mon, 23 Mar 2015 12:48:03 +0000 http://www.hindawi.com/journals/jchem/2015/418731/ This study selected 10 extracts from Tunisian chetoui O. europaea variety for their total phenolics, flavonoids, and phytochemical analyses as well as for their antioxidant and antimicrobial activities determination. The in vitro antioxidant property was investigated using DPPH, ferric reducing antioxidant capacity (FRAP), oxygen reducing antioxidant capacity (ORAC), and β-carotene-linoleic acid bleaching assays while antimicrobial activity was evaluated using macrodilutions method. For all organs of chetoui O. europaea variety, the investigated activities were found to be higher in the polar extracts (ethyl acetate, methanol, and methanol/water). These activities were correlated with the presence of phenolic compounds. Phytochemical analyses revealed that the crude extracts contain triterpenoids, quinones, and flavonoids. High performance liquid chromatography (HPLC) and high performance thin layer chromatography (HPTLC) confirmed the presence of phenolic compounds in the studied extracts. Ines Khlif, Karim Jellali, Thomas Michel, Maria Halabalaki, Alexios Leandros Skaltsounis, and Noureddine Allouche Copyright © 2015 Ines Khlif et al. All rights reserved. Analysis of Antifungal Components in the Galls of Melaphis chinensis and Their Effects on Control of Anthracnose Disease of Chinese Cabbage Caused by Colletotrichum higginsianum Sun, 22 Mar 2015 14:16:56 +0000 http://www.hindawi.com/journals/jchem/2015/850103/ Fungal pathogens caused various diseases which resulted in heavy yield and quality losses on plants of commercial interests such as fruits, vegetables, and flowers. In our preliminary experimental results, the methanol extracts of four species of medicinal plants Melaphis chinensis, Eugenia caryophyllata, Polygonum cuspidatum, and Rheum officinale possessed antifungal activity to causal agent of cabbage anthracnose, Colletotrichum higginsianum. Thus it was conducted to identify and quantify the chemical constituents in these herbs and to assess the antifungal effects of these compounds. Among the tested principles, the indicator compound methyl gallate from M. chinensis was the most effective one against the conidial germination. In addition, it exhibited significant effects of controlling anthracnose disease of Chinese cabbage caused by C. higginsianum PA-01 in growth chamber. These results indicate that M. chinensis may be potential for further development of plant-derived pesticides for control of anthracnose of cabbage and other cruciferous crops. Ping-Chung Kuo, Ting-Fang Hsieh, Mei-Chi Lin, Bow-Shin Huang, Jenn-Wen Huang, and Hung-Chang Huang Copyright © 2015 Ping-Chung Kuo et al. All rights reserved. Analysis of Physiochemical Parameters to Evaluate the Drinking Water Quality in the State of Perak, Malaysia Sun, 22 Mar 2015 11:32:18 +0000 http://www.hindawi.com/journals/jchem/2015/716125/ The drinking water quality was investigated in suspected parts of Perak state, Malaysia, to ensure the continuous supply of clean and safe drinking water for the public health protection. In this regard, a detailed physical and chemical analysis of drinking water samples was carried out in different residential and commercial areas of the state. A number of parameters such as pH, turbidity, conductivity, total suspended solids (TSS), total dissolved solids (TDS), and heavy metals such as Cu, Zn, Mg, Fe, Cd, Pb, Cr, As, Hg, and Sn were analysed for each water sample collected during winter and summer periods. The obtained values of each parameter were compared with the standard values set by the World Health Organization (WHO) and local standards such as National Drinking Water Quality Standard (NDWQS). The values of each parameter were found to be within the safe limits set by the WHO and NDWQS. Overall, the water from all the locations was found to be safe as drinking water. However, it is also important to investigate other potential water contaminations such as chemicals and microbial and radiological materials for a longer period of time, including human body fluids, in order to assess the overall water quality of Perak state. N. Rahmanian, Siti Hajar Bt Ali, M. Homayoonfard, N. J. Ali, M. Rehan, Y. Sadef, and A. S. Nizami Copyright © 2015 N. Rahmanian et al. All rights reserved.