Journal of Spectroscopy The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Influence of the Chemical Composition in the Electrochemical Response of Permanent Magnets Sun, 29 Nov 2015 12:06:12 +0000 The corrosion behavior of permanent magnets with different chemical composition was evaluated. Permanent magnets were tested in 3.5% NaCl solution at room temperature using electrochemical technics such as polarization curves, open-circuit potential, linear polarization resistance, and electrochemical impedance spectroscopy measurements. Results have shown that corrosion rate is affected by Nd, Pr, and Co content. Analysis by scanning electron microscopy has shown that pitting attack is the main mode of degradation of the magnets, while Co addition reduces it and Pr addition increases it. S. Godavarthi, J. Porcayo-Calderon, E. Vazquez-Velez, M. Casales-Diaz, D. M. Ortega-Toledo, and L. Martinez-Gomez Copyright © 2015 S. Godavarthi et al. All rights reserved. Investigation on Structural and Optical Properties of Willemite Doped Mn2+ Based Glass-Ceramics Prepared by Conventional Solid-State Method Tue, 24 Nov 2015 12:28:06 +0000 Mn-doped willemite (Zn2SiO4:Mn2+) glass-ceramics derived from ZnO-SLS glass system were prepared by a conventional melt-quenching technique followed by a controlled crystallization step employing the heat treatment process. Soda lime silica (SLS) glass waste, ZnO, and MnO were used as sources of silicon, zinc, and manganese, respectively. The obtained glass-ceramic samples were characterized using the X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared (FTIR), UV-Visible (UV-Vis), and photoluminescence (PL) spectroscopy. The results of XRD revealed that ZnO crystal and willemite (β-Zn2SiO4) were presented as major embedded crystalline phases. This observation was consistent with the result of FESEM which showed the presence of irregularity in shape and size of willemite crystallites. FTIR spectroscopy exhibits the structural evolution of willemite based glass-ceramics. The optical band gap shows a decreasing trend as the Mn-doping content increased. Photoluminescent technique was applied to characterize the role of Mn2+ ions when entering the willemite glass-ceramic structure. By measuring the excitation and emission spectra, the main emission peak of the glass-ceramic samples located at a wavelength of 585 nm after subjecting to 260 nm excitations. The following results indicate that the obtained glass-ceramics can be applied as phosphor materials. Nur Farhana Samsudin, Khamirul Amin Matori, Josephine Ying Chi Liew, Yap Wing Fen, Mohd Hafiz Mohd Zaid, and Zarifah Nadakkavil Alassan Copyright © 2015 Nur Farhana Samsudin et al. All rights reserved. Detection of Lard in Ink Extracted from Printed Food Packaging Using Fourier Transform Infrared Spectroscopy and Multivariate Analysis Thu, 19 Nov 2015 15:57:18 +0000 Fourier transform infrared (FTIR) spectroscopy combined with chemometrics was utilised to discriminate the presence of lard in extracted ink of printed food packaging. Two spectral regions (full spectra, 3999–649 cm−1, and combination of two regions, 3110–2630 cm−1 and 1940–649 cm−1) of lard, commercial gravure ink, and the blends of both were selected and used to develop a Soft Independent Modelling of Class Analogy (SIMCA) model. The score plots obtained from the Principal Component Analysis (PCA) revealed that the maximum number of factors (7 factors) was needed to explain 84% of the total variance. SIMCA was employed as the method to classify the samples into their specific groups. Si versus Hi plots showed that the calibration standards can be classified as lard-containing standards. Sample 2 was deduced to have the highest possibility of containing lard, while only samples 5 and 7 cannot be classified as lard-containing samples. These results demonstrated that FTIR spectroscopy, when combined with multivariate analysis, can provide a rapid method with no excessive sample preparation to detect the presence of lard in ink of foodstuff packaging. Syazwani Ramli, Rosnita A. Talib, Russly A. Rahman, Norhazlin Zainuddin, Siti Hajar Othman, and Norma M. Rashid Copyright © 2015 Syazwani Ramli et al. All rights reserved. SEM and AES Analysis of Corrosion in Steel Cans of Meat and Poultry Food Industry Influenced by Microorganisms Affecting the Competitiveness in Northwest of Mexico Thu, 05 Nov 2015 08:34:45 +0000 The food industry of meat and poultry food is very important activity in the economy of the northwest of Mexico where the Sonora state (with Hermosillo and Santa Ana cities as arid and semiarid zones and Guaymas as marine regions) and Baja California state (Mexicali as arid zone and Tijuana as marine region) are located. The meat and poultry industries produce meat, milk, and eggs, which are recommended for their nutritive properties. An evaluation of micro- and nanocorrosion was made with an optical sensor used to detect microorganisms (MO) inside of the steel cans. The techniques applied to evaluate the deterioration were the Scanning Electron Microscopy (SEM) and the Auger Electron Spectroscopy (AES), to obtain the morphology of microorganisms formed in the internal area of the metallic containers. Also the chemical composition to identify and determine the conditions for growth of microorganisms was obtained with respect to moisture and temperature in each region analyzed. The sulfur was the principal pollutant agent in arid and semiarid zones and chloride in marine zones that promoted the corrosion process. The presence of corrosion in the food industry decreases their competitiveness. César Sánchez Ocampo, Gustavo López Badilla, Elizabeth Romero Samaniego, Sandra Luz Toledo Perea, and Josefina Campos García Copyright © 2015 César Sánchez Ocampo et al. All rights reserved. Investigating the Degradability of HDPE, LDPE, PE-BIO, and PE-OXO Films under UV-B Radiation Sun, 01 Nov 2015 09:39:05 +0000 The changes in structural properties of high density polyethylene films (HDPE), low density polyethylene films (LDPE), biodegradable polyethylene (PE-BIO), and oxodegradable polyethylene (PE-OXO) films exposed to UV-B radiation were studied. The carbonyl and vinyl index, the crystalline phase fraction, and the dichroic ratio were used to evaluate the photooxidation of these polymers. The results obtained show that LDPE and HDPE undergo a major degree of oxidation and an increase in the crystalline phase fraction comparing to PE-BIO and PE-OXO. If the LDPE and HDPE are pretreated by an accurate radiation UV-B dosage before its different commercial uses or in its final disposition, they can become an option for biodegradable material without the necessity of adding organic agents or photosensitizers. A. Martínez-Romo, R. González-Mota, J. J. Soto-Bernal, and I. Rosales-Candelas Copyright © 2015 A. Martínez-Romo et al. All rights reserved. Detection of Counterfeit Tequila by Fluorescence Spectroscopy Thu, 15 Oct 2015 11:25:24 +0000 An ultraviolet (UV) light induced fluorescence study to discriminate fake tequila from genuine ones is presented. A portable homemade system based on four light emitting diodes (LEDs) from 255 to 405 nm and a miniature spectrometer was used. It has been shown that unlike fake and silver tequila, which produce weak fluorescence signal, genuine mixed, rested, and aged tequilas show high fluorescence emission in the range from 400 to 750 nm. The fluorescence intensity grows with aging in 100% agave tequila. Such fluorescence differences can even be observed with naked eyes. The presented results demonstrate that the fluorescence measurement could be a good method to detect counterfeit tequila. José Manuel de la Rosa Vázquez, Diego Adrián Fabila-Bustos, Luis Felipe de Jesús Quintanar-Hernández, Alma Valor, and Suren Stolik Copyright © 2015 José Manuel de la Rosa Vázquez et al. All rights reserved. Corrigendum to “Ultrafast Probe of Carrier Diffusion and Nongeminate Processes in a Single CdSSe Nanowire” Wed, 07 Oct 2015 06:19:08 +0000 Peter S. Eldridge, Jolie C. Blake, and Lars Gundlach Copyright © 2015 Peter S. Eldridge et al. All rights reserved. Quantitative Determination of Germinability of Puccinia striiformis f. sp. tritici Urediospores Using Near Infrared Spectroscopy Technology Sun, 04 Oct 2015 14:02:38 +0000 Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is an important disease on wheat. In this study, quantitative determination of germinability of Pst urediospores was investigated by using near infrared reflectance spectroscopy (NIRS) combined with quantitative partial least squares (QPLS) and support vector regression (SVR). The near infrared spectra of the urediospore samples were acquired using FT-NIR MPA spectrometer and the germination rate of each sample was measured using traditional spore germination method. The best QPLS model was obtained with vector correction as the preprocessing method of the original spectra and 4000–12000 cm−1 as the modeling spectral region while the modeling ratio of the training set to the testing set was 4 : 1. The best SVR model was built when vector normalization was used as the preprocessing method, the modeling ratio was 5 : 1 and the modeling spectral region was 8000–11000 cm−1. The results showed that the effect of the best model built using QPLS or SVR was satisfactory. This indicated that quantitative determination of germinability of Pst urediospores using near infrared spectroscopy technology is feasible. A new method based on NIRS was provided for rapid, automatic, and nondestructive determination of germinability of Pst urediospores. Yaqiong Zhao, Feng Qin, Pei Cheng, Xiaolong Li, Zhanhong Ma, Longlian Zhao, Junhui Li, and Haiguang Wang Copyright © 2015 Yaqiong Zhao et al. All rights reserved. Analysis of ACAM Data for Trace Gas Retrievals during the 2011 DISCOVER-AQ Campaign Thu, 01 Oct 2015 08:34:39 +0000 To improve the trace gas retrieval from Airborne Compact Atmospheric Mapper (ACAM) during the DSICOVER-AQ campaigns, we characterize the signal to noise ratio (SNR) of the ACAM measurement. From the standard deviations of the fitting residuals, the SNRs of ACAM nadir measurements are estimated to vary from ~300 at 310 nm to ~1000 in the blue spectral region; the zenith data are noisier due to reduced levels of illumination and lower system throughput and also show many more pixels with abrupt anomalous values; therefore, a new method is developed to derive a solar irradiance reference at the top of the atmosphere (TOA) from average nadir measurements, at instrument spectral resolution and including instrument calibration characteristics. Using this reference can significantly reduce fitting residuals and improve the retrievals. This approach derives an absolute reference for direct fitting algorithms involving radiative transfer calculations and thus can be applied to both aircraft and ground-based measurements. The comparison of ACAM radiance with simulations using coincident ozonesonde and OMI data shows large wavelength-dependent biases in ACAM data, varying from ~−19% at 310 nm to 5% at 360 nm. Correcting ACAM radiance in direct-fitting based ozone profile algorithm significantly improves the consistency with OMI total ozone. C. Liu, X. Liu, M. G. Kowalewski, S. J. Janz, G. González Abad, K. E. Pickering, K. Chance, and L. N. Lamsal Copyright © 2015 C. Liu et al. All rights reserved. Retrieval of Atmospheric CO2 and CH4 Variations Using Ground-Based High Resolution Fourier Transform Infrared Spectra Wed, 30 Sep 2015 14:30:01 +0000 High resolution Fourier transform near IR solar spectra are used to estimate the column-averaged dry-air mole fraction (DMF) of CO2 and variations in the atmosphere. The preliminary retrieval results for CO2 and variations in the area of Hefei, China, are presented, and the underlying error sources are also analyzed. Both a forward analysis and an inversion algorithm are included in the retrieval. The forward analysis uses the modeled atmospheric transmittance to line-by-line (LBL) convolute the instrument line shape function. The influences of the temperature, pressure, humidity, and a priori gases are considered in the atmospheric transmittance model. The inversion algorithm is based on the nonlinear iterative and nonlinear least squares spectral fitting, which is used to obtain and (which represent vertical column density of CO2 and , resp.). Furthermore, the is also retrieved for converting the VCDs into DMFs. DMFs are final products of data analysis. The inversion results can clearly resolve the tiny variations of CO2 and under strong atmospheric background. Spectral fitting residuals for both and are less than 0.5%. Finally, CO2 and diurnal variations are investigated based on a typical observation. About 2 ppm amplitude for diurnal variations and less than 15 ppb amplitude for are observed. Tian Yuan, Liu Cheng, Sun You Wen, Xie Pin Hua, Wang Wei, Liu Wen Qing, Liu Jian Guo, Li Ang, Hu Ren Zhi, and Zeng Yi Copyright © 2015 Tian Yuan et al. All rights reserved. Corrigendum to “Oxidative Stability of Baru (Dipteryx alata Vogel) Oil Monitored by Fluorescence and Absorption Spectroscopy” Tue, 29 Sep 2015 11:21:32 +0000 Vanessa D. Silva, José N. Conceição, Ivan P. Oliveira, Caroline H. Lescano, Rozanna M. Muzzi, Omar P. S. Filho, Edemilson C. Conceição, Gleison A. Casagrande, and Anderson R. L. Caires Copyright © 2015 Vanessa D. Silva et al. All rights reserved. Determination of Metal Contents of Various Fibers Used in Textile Industry by MP-AES Mon, 21 Sep 2015 12:02:06 +0000 The concentrations of metals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Tl, and Zn) in various textile fibers (cotton, acrylic, polyester, nylon, viscose, and polypropylene) of different colors (red, white, green, blue, yellow, orange, black, brown, purple, pink, navy, burgundy, beige, and grey) were determined by microwave plasma-atomic emission spectroscopy (MP-AES). Textile fibers were collected from the various textile plants in Gaziantep-Kahramanmaraş, Turkey. Heavy metals concentrations in all examined textile fibers after wet digestion were found to be high, whereas in the artificial sweat extract they were low. The only lead concentrations in textile fibers analyzed after extraction in the artificial sweat solution were found higher than limit values given by Oeko-Tex. Şana Sungur and Fatih Gülmez Copyright © 2015 Şana Sungur and Fatih Gülmez. All rights reserved. Canopy Spectral Characterization of Wheat Stripe Rust in Latent Period Wed, 09 Sep 2015 11:09:54 +0000 Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the important wheat diseases worldwide. In this study, the spectral data were collected from wheat canopy during the latent period inoculated with three different concentrations of urediniospores and classification models based on discriminant partial least squares (DPLS) were built to differentiate leaves with and without infection of the stripe rust pathogen. The effects of different spectra features, wavebands, and the number of the samples used in modeling on the performances of the models were assessed. The results showed that, in the spectral region of 325–1075 nm, the model with the spectral feature of 2nd derivative of Pseudoabsorption index had better accuracy than others. The average accuracy rate was 97.28% for the training set and 92.98% for the testing set. In the waveband of 925–1075 nm, the model with the spectral feature of 1st derivative Pseudoabsorption index had better accuracy than other models, and the average accuracy rates were 98.27% and 94.33% for the training and testing sets, respectively. The results demonstrated that wheat stripe rust in latent period can be qualitatively identified based on the canopy spectral detection. Thus, the method can be used for early monitoring of infections of wheat stripe rust. Qi Liu, Yilin Gu, Shuhe Wang, Cuicui Wang, and Zhanhong Ma Copyright © 2015 Qi Liu et al. All rights reserved. Effect of High Pressure on the Molecular Structure and π-Electrons Delocalization of Canthaxanthin as Revealed by Raman Spectra Wed, 26 Aug 2015 10:45:51 +0000 The effect of high pressure on the molecular structure and π-electron delocalization of canthaxanthin was studied by in situ resonance Raman spectroscopy. Changes in the characteristic band frequency and the pressure of canthaxanthin were described. The effect of pressure on π-electron delocalization was also discussed. Results show that the characteristic bands of canthaxanthin increase and reach high wavenumbers. The correlations between Raman frequency of the three main bands and pressure are listed as follows: (C=C) = 3.43P + 1512.3, (C-C) = 3.29P + 1156.1, and (CH3) = 2.16P + 1006.3. The frequency multiplication of canthaxanthin changes as pressure is altered. The pressure effect on the (C=C) mode is more susceptible than on the (C-C) mode, which can be explained by the fact that the β-ring twists to a larger angle from the plane of the conjugated main chain under high pressure, leading to a lower degree of the π-electrons delocalization. The Raman spectra are recovered after the compression-decompression cycle indicating the canthaxanthin has no evident phase change under our experimental conditions. Shun-li Ou-Yang, Nan-nan Wu, and Yan-jie Tian Copyright © 2015 Shun-li Ou-Yang et al. All rights reserved. Spectroscopic Study of Cytosine Methylation Effect on Thermodynamics of DNA Duplex Containing CpG Motif Wed, 26 Aug 2015 08:12:52 +0000 Effect of cytosine methylation on DNA duplexes was studied by using a model system of three self-complementary DNA octamers containing central CpG motif surrounded by a couple of AT base pairs, CAACGTTG, CATCGATG, and CTTCGAAG, and their analogues with the central cytosine methylated at C5 position. Temperature dependences of 1H NMR, UV absorption, and Raman scattering spectra measured for aqueous solutions at concentrations of different orders of magnitude were subjected to a joint analysis that allowed an accurate determination of the enthalpy and entropy of duplex formation. It was revealed that the changes of the enthalpy and entropy contributions are strongly dependent on the base composition in the vicinity of the CpG motif. Václav Římal, Ondřej Socha, Josef Štěpánek, and Helena Štěpánková Copyright © 2015 Václav Římal et al. All rights reserved. Micellar Enhanced Three-Dimensional Excitation-Emission Matrix Fluorescence for Rapid Determination of Antihypertensives in Human Plasma with Aid of Second-Order Calibration Methods Sun, 23 Aug 2015 13:48:01 +0000 A highly sensitive three-dimensional excitation-emission fluorescence method was proposed to determine antihypertensives including valsartan and amlodipine besylate in human plasma with the aid of second-order calibration methods based on parallel factor analysis (PARAFAC) and alternating trilinear decomposition (ATLD) algorithms. Antihypertensives with weak fluorescent can be transformed into a strong fluorescent property by changing microenvironment in samples using micellar enhanced surfactant. Both the adopted algorithms with second-order advantage can improve the resolution and directly attain antihypertensives concentration even in the presence of potential strong intrinsic fluorescence from human plasma. The satisfactory results can be achieved for valsartan and amlodipine besylate in complicated human plasma. Furthermore, some statistical parameters and figures of merit were evaluated to investigate the performance of the proposed method, and the accuracy and precision of the proposed method were also validated by the elliptical joint confidence region (EJCR) test and repeatability analysis of intraday and interday assay. The proposed method could not only light a new avenue to directly determine valsartan or amlodipine besylate in human plasma, but also hold great potential to be extended as a promising alternative for more practical applications in the determination of weak fluorescent drugs. Hai-Yan Fu, He-Dong Li, Chuang Ni, Tian-Ming Yang, Yao Fan, Hao Zhang, Ji Yang, Lin Chen, and Yuan-Bin She Copyright © 2015 Hai-Yan Fu et al. All rights reserved. Quantification of Tremolite in Friable Material Coming from Calabrian Ophiolitic Deposits by Infrared Spectroscopy Wed, 05 Aug 2015 14:17:48 +0000 The aim of this study is to identify the infrared absorption band suitable for quantifying tremolite in three powdered samples (fine, medium, and large size classes) coming from a quarry of ophiolitic friable rocks in the western part of the Calabria region of Italy. Three IR bands were considered: OH stretching band between 3700 and 3650 cm−1, the stretching bands of the Si-O-Si linkage between 1200 and 900 cm−1, and the absorbance band at 756 cm−1 attributable to tremolite. The amount of tremolite in the test samples was quantified by using the curve parameters of the three analytical bands. The quantitative analysis of tremolite using the band due to OH stretchings (3700–3650 cm−1) and the bands attributed to the Si-O-Si stretchings (1200–900 cm−1) showed high values for all test samples. Their use overestimated the tremolite amount because both bands were affected at the interfering mineral silicates such as talc, kaolinite, chlorite, and serpentinites. The abundant presence of antigorite in studied samples mainly in medium size class sample had a key role in our findings. The band at 756 cm−1 was not affected at the interfering minerals and can be used for quantitative analysis of tremolite in sample coming from ophiolitic deposits. Antonella Campopiano, Angelo Olori, Annapaola Cannizzaro, Antonino Iannò, and Pietro Paolo Capone Copyright © 2015 Antonella Campopiano et al. All rights reserved. Spectroscopy in Materials Chemistry Wed, 05 Aug 2015 12:42:07 +0000 Tifeng Jiao, Nikša Krstulović, Bing Wu, Xinqing Chen, and Qingrui Zhang Copyright © 2015 Tifeng Jiao et al. All rights reserved. FT-IR Characterization of Pollen Biochemistry, Viability, and Germination Capacity in Saintpaulia H. Wendl. Genotypes Wed, 05 Aug 2015 07:58:25 +0000 FT-IR characterization of pollen biochemistry was analyzed to detect possible connection with the viability (by staining with potassium iodide, 25%) and the germination capacity (on solid nutrient medium), in 15 Saintpaulia genotypes. Vibrational spectroscopy indicates that the pollen of S. ionantha genotype “Red Velvet” is rich in proteins, lipids, triglycerides, and esters and has a viability of 88.4% and a low germination capacity (27.16%). For S. ionantha “Jolly Red” and “Lucky Ladybug” genotypes, pollen showed high viability (88.81–91.49%) and low germination capacity (23.02–9.17%), even though the pollen is rich in carbohydrates. S. ionantha “Aloha Orchid” genotype has the highest percentage of viability (94.32%) and germination capacity (45.73%) and a rich content of carbohydrates and polygalacturonic acids. In S. rupicola and S. ionantha genotypes, the rich content of polygalacturonic acids, lipids, and carbohydrates favourably influenced the germination capacity. Spectroscopic result indicates, through different absorbance band intensity, a possible link between biochemical composition, viability, and germination capacity of Saintpaulia pollen. To determine exactly the relation between biochemistry and biological processes, it is necessary to initiate quantitative researches. Erzsebet Buta, Maria Cantor, Răzvan Ștefan, Rodica Pop, Ioana Mitre Jr., Mihai Buta, and Radu E. Sestraș Copyright © 2015 Erzsebet Buta et al. All rights reserved. Spin-Glass Behavior, Magnetic, and IR Spectroscopy Analysis of Multimetallic Compound Ni0.25Mn1.25[Fe(CN)6]·6.1H2O Tue, 04 Aug 2015 13:16:23 +0000 Multimetallic Prussian blue compound Ni0.25Mn1.25[Fe(CN)6]·6.1H2O has been prepared by coprecipitation. The temperature-dependent magnetic susceptibilities show the magnet transition for the compound at 8.5 K. According to DC variable-temperature magnetic susceptibility paramagnetic Curie temperature is −9.32 K. The observed value of coercive field (Hc) and the remanent magnetization (Mr) for the compound are 0.32 KOe and 0.36 . According to study of zero-field-cooled (ZFC) and field-cooled (FC) magnetization curves and AC magnetization curves, there exists a spin-glass behaviour in the compound, which exhibits freezing temperature  K, below magnetic transition  K; that glass behavior is termed “reentrant” spin glass. Qing Lin, Xiaofang Liu, Yun He, Haifu Huang, and Xingcan Shen Copyright © 2015 Qing Lin et al. All rights reserved. Development and Characterization of Biocompatible Fullerene [C60]/Amphiphilic Block Copolymer Nanocomposite Tue, 04 Aug 2015 13:05:33 +0000 We report a supramolecular process for the synthesis of well-defined fullerene (C60)/polymer colloid nanocomposites in an aqueous solution via complex formation. A biocompatible triblock poly(4-vinylpyridine)-b-polyethylene-b-poly(4-vinylpyridine), P4VP8-b-PEO105-b-P4VP8, was synthesized by atom transfer radical polymerization. The block copolymer formed complexes with C60 in toluene and resulted in fullerene assembly in cluster form. Nanocomposite dispersion in an aqueous solution could be obtained using an aged solution of the polymer/C60/toluene solution by a solvent evaporation technique. The UV-Vis and FTIR spectroscopy confirmed the complex formation of fullerene with the polymer which plays a significant role in controlling the PDI and size of polymer/C60 micelles in the toluene solution. The particle size and morphology of P4VP8-b-PEO105-b-P4VP8 and P4VP8-b-PEO105-b-P4VP8/C60 mixture were studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). In a cytotoxicity test, both pure polymer and the resulting polymer/C60 composite in water showed more than 90% cell viability at 1 mg/mL concentration. Alok Chaurasia, Nanda Gopal Sahoo, James T. McLeskey Jr., and Xiao Hu Copyright © 2015 Alok Chaurasia et al. All rights reserved. Raman Spectroscopy for Understanding of Lithium Intercalation into Graphite in Propylene Carbonated-Based Solutions Tue, 04 Aug 2015 12:44:54 +0000 Electrochemical lithium intercalation within graphite was investigated in propylene carbonate (PC) containing different concentrations, 0.4, 0.9, 1.2, 2.2, 2.8, 3.8, and 4.7 mol dm−3, of lithium perchlorate, LiClO4. Lithium ion was reversibly intercalated into and deintercalated from graphite in 3.8 and 4.7 mol dm−3 solutions despite the use of pure PC as the solvent. However, ceaseless solvent decomposition and intense exfoliation of the graphene layers occurred in other solutions. The results of the Raman spectroscopic analysis indicated that contact ion pairs are present in 3.8 and 4.7 mol dm−3 solutions, which suggested that the presence of contact ion pairs is an important factor that determines the solid electrolyte interphase- (SEI-) forming ability in PC-based electrolytes. Yang-Soo Kim and Soon-Ki Jeong Copyright © 2015 Yang-Soo Kim and Soon-Ki Jeong. All rights reserved. Solar Photocatalytic Degradation of Typical Indoor Air Pollutants Using TiO2 Thin Film Codoped with Iron(III) and Nitrogen Tue, 04 Aug 2015 11:12:24 +0000 A type of iron and nitrogen codoped titania thin film was prepared by sol-gel method to degrade three typical indoor air pollutants: formaldehyde (HCHO), ammonia (NH3), and benzene (C6H6) under solar light. X-ray diffraction (XRD), UV-Vis spectroscopy, and energy dispersive spectra (EDS) were employed to characterize the photocatalysts. The results showed that the Fe/N codoped TiO2 had a stronger absorption in the visible region than pure, Fe-doped, and N-doped TiO2 and exhibited excellent photocatalytic ability for the degradation of indoor HCHO, NH3, and C6H6. When the three pollutants existed in indoor air at the same time, the removal percentages of HCHO, NH3, or C6H6 after 6 h photocatalytic reaction under solar light reached 48.8%, 50.6%, and 32.0%. The degradation reaction of the three pollutants followed the pseudo-first-order kinetics with the reaction rate constants in the order of 0.110 h−1 for ammonia, 0.109 h−1 for formaldehyde, and 0.060 h−1 for benzene. The reaction rate constant decreased with the increase of initial reactant concentration, which reflected that there was oxidation competition between the substrate and its intermediate during the photocatalytic process. Shuaijie Wang and Xingxing Cheng Copyright © 2015 Shuaijie Wang and Xingxing Cheng. All rights reserved. Effect of Contact Time and Gas Component on Interfacial Tension of CO2/Crude Oil System by Pendant Drop Method Mon, 03 Aug 2015 14:29:11 +0000 Pendant drop method has been used to measure the equilibrium interfacial tension and dynamic interfacial tension of CO2/crude oil system under the simulated-formation condition, in which the temperature is 355.65 K and pressure ranges from 0 MPa to 30 MPa. The test results indicated that the equilibrium interfacial tension of CO2/crude oil systems decreased with the increase of the systematic pressure. The dynamic interfacial tension of CO2/original oil, CO2/remaining oil, and CO2/produced oil systems is large at the initial contact and decreases gradually after that, and then finally it reaches dynamic balance. In addition, the higher the pressure is, the larger the magnitude of changing of CO2/crude oil interfacial tension with time will reduce. Moreover, by PVT phase experiment, gas-oil ratio, gas composition, and well fluid composition have been got, and different contents of light components in three oil samples under reservoir conditions have also been calculated. The relationship between equilibrium interfacial tensions and pressures of three different components of crude oil and CO2 system was studied, and the higher C1 is, the lower C2–C10 will be, and the equilibrium interfacial tension will get higher. Therefore, the effect of light weight fractions on interfacial tension under formation conditions was studied. Xin Wang, Lifeng Liu, Zengmin Lun, Chengyuan Lv, Rui Wang, Haitao Wang, and Dong Zhang Copyright © 2015 Xin Wang et al. All rights reserved. Preparation and Application of Titanate Nanotubes on Dye Degradation from Aqueous Media by UV Irradiation Mon, 03 Aug 2015 13:25:13 +0000 Titanate nanotubes were synthesized by a hydrothermal method using commercial TiO2 powder and then used as a photocatalyst. The titanate nanotubes were synthesized by varying the hydrothermal temperature from 110°C to 180°C. The morphological changes and phase transformation of the TiO2 nanotubes were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The particles’ scattering behavior was investigated by Raman studies, and the surface area of the nanotubes was determined by a Brunauer, Emmett, and Teller (BET) analysis. Comparative studies show that the surface area of nanotubes increases with increasing temperature up to 130°C. The catalytic behavior of the synthesized nanotubes was also studied. The as-prepared titanate nanotubes were applied to methylene blue (MB, an organic dye) degradation in aqueous media by UV irradiation. Approximately 99% of the dye was removed from the aqueous media using 2 g/L titanate nanotube when the initial dye concentration was 9 mg/L. The total irradiation time was 2 h. Rui Liu, Wein-Duo Yang, Hui-Ju Chueng, and Bin-Qiao Ren Copyright © 2015 Rui Liu et al. All rights reserved. Effects of Chlorinated Polypropylene on the Conformation of Polypropylene in Polypropylene/Chlorinated Polypropylene/Polyaniline Composites Mon, 03 Aug 2015 12:20:21 +0000 We investigated the changes in the conformation and crystalline structure of polypropylene (PP) using a combination of Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC) based on PP/chlorinated PP (CPP)/polyaniline (PANI) composites. The DSC heating thermograms and WAXD patterns of the PP/CPP/PANI composites showed that the β-crystal was affected greatly by the CPP content. Characterization of the specific regularity in the infrared band variation showed that the conformational orders of the helical sequences in PP exhibited major changes that depended on the CPP content. Initially, the intensity ratio of increased with the CPP concentration and reached its maximum level when the CPP content was <13.22% before decreasing as the CPP content increased further. The effect of increased temperature on the conformation of PP was studied by in situ FTIR. Initially, the intensity ratio of decreased slowly with increasing the temperature up to 105°C before decreasing sharply with further increases in temperature and then decreasing slowly again when the temperature was higher than 128°C. Jianjun Chen, Yueyue Jia, Zhiye Zhang, Xinlong Wang, and Lin Yang Copyright © 2015 Jianjun Chen et al. All rights reserved. Laser Raman Spectroscopy with Different Excitation Sources and Extension to Surface Enhanced Raman Spectroscopy Mon, 03 Aug 2015 11:57:25 +0000 A dispersive Raman spectrometer was used with three different excitation sources (Argon-ion, He-Ne, and Diode lasers operating at 514.5 nm, 633 nm, and 782 nm, resp.). The system was employed to a variety of Raman active compounds. Many of the compounds exhibit very strong fluorescence while being excited with a laser emitting at UV-VIS region, hereby imposing severe limitation to the detection efficiency of the particular Raman system. The Raman system with variable excitation laser sources provided us with a desired flexibility toward the suppression of unwanted fluorescence signal. With this Raman system, we could detect and specify the different vibrational modes of various hazardous organic compounds and some typical dyes (both fluorescent and nonfluorescent). We then compared those results with the ones reported in literature and found the deviation within the range of ±2 cm−1, which indicates reasonable accuracy and usability of the Raman system. Then, the surface enhancement technique of Raman spectrum was employed to the present system. To this end, we used chemically prepared colloidal suspension of silver nanoparticles as substrate and Rhodamine 6G as probe. We could observe significant enhancement of Raman signal from Rhodamine 6G using the colloidal solution of silver nanoparticles the average magnitude of which is estimated to be 103. Md. Wahadoszamen, Arifur Rahaman, Nabil Md. Rakinul Hoque, Aminul I Talukder, Kazi Monowar Abedin, and A. F. M. Yusuf Haider Copyright © 2015 Md. Wahadoszamen et al. All rights reserved. Improving Hyperspectral Image Classification Method for Fine Land Use Assessment Application Using Semisupervised Machine Learning Mon, 03 Aug 2015 11:56:33 +0000 Study on land use/cover can reflect changing rules of population, economy, agricultural structure adjustment, policy, and traffic and provide better service for the regional economic development and urban evolution. The study on fine land use/cover assessment using hyperspectral image classification is a focal growing area in many fields. Semisupervised learning method which takes a large number of unlabeled samples and minority labeled samples, improving classification and predicting the accuracy effectively, has been a new research direction. In this paper, we proposed improving fine land use/cover assessment based on semisupervised hyperspectral classification method. The test analysis of study area showed that the advantages of semisupervised classification method could improve the high precision overall classification and objective assessment of land use/cover results. Chunyang Wang, Zengzhang Guo, Shuangting Wang, Liping Wang, and Chao Ma Copyright © 2015 Chunyang Wang et al. All rights reserved. Synthesis and Catalytic Performances of a Novel Zn-MOF Catalyst Bearing Nickel Chelating Diimine Carboxylate Ligands for Ethylene Oligomerization Mon, 03 Aug 2015 11:55:33 +0000 A novel Zn-MOF[Zn3(OH)2L2] was synthesized from dicarboxylate ligands with diimine groups (1,4-bis(4-CO2HC6H4)-2,3-dimethyl-1,4-diazabutadiene). The physicochemical properties of the material were characterized by a series of technologies including XRD, SEM, and ICP. In order to adapt to the ethylene oligomerization process, a catalyst (denoted as Cat.A) possessing active Ni2+ centers was prepared by a postsynthetic treatment method using dichloride nickel as a nickel source in this work. For comparison, α-diimine ligands with/without dicarboxylic acid groups reacted with dichloride nickel to obtain homogenous Cat.B and Cat.C, respectively. The effects of reaction parameters, including n(Al)/n(Ni), temperature, and pressure on the oligomerization activities and oligomers distribution were investigated. The results demonstrated that all of catalysts used with diethylaluminum chloride were active for the ethylene oligomerization. Among them, Cat.A and Cat.B showed higher catalytic activities and higher selectivities to low-carbon α-olefins at atmospheric pressure. The Cat.A exhibited the optimal catalytic activity [6.7 × 105 g/(mol·Ni·h·atm)] for C4 (91.8%) under the conditions of Al/Ni = 1500, P = 1.0 atm, T = 20°C. In addition, Cat.A and Cat.B presented large amount of ethylene polymer, while Cat.C had a higher catalytic activity of ethylene oligomerization at high pressure. Suyan Liu, Ying Zhang, Quan Huo, Sasa He, and Yang Han Copyright © 2015 Suyan Liu et al. All rights reserved. Hydrothermal Synthesis of High Crystalline Silicalite from Rice Husk Ash Mon, 03 Aug 2015 11:28:27 +0000 The objective of this research work was to evaluate the hydrothermal synthesis of silicalite with high crystallinity within a small particle size. The current study focused on investigating the effects of silica sources such as rice husk ash (RHA) and silica gel (SG), crystallization time, and ratios of NaOH/SiO2, H2O/NaOH, and SiO2/TPABr. The crystallinity, particle size, and morphology were characterized by FT-IR, XRD, particle size analyser, and SEM. The conclusion of the main findings indicated that the XRD patterns of these samples clearly showed a pure phase of MFI structure corresponding to FT-IR spectra with vibration mode at 550 and 1223 cm−1. The highest crystallinity was obtained at reaction time only 6 hours with the mole ratios of NaOH/SiO2, H2O/NaOH and SiO2/TPABr as 0.24, 155, and 30, respectively. When SG was used as a silica source, it was found that the particle size was smaller than that from RHA. The morphologies of all silicalite samples were coffin and cubic-like shape. Chaiwat Kongmanklang and Kunwadee Rangsriwatananon Copyright © 2015 Chaiwat Kongmanklang and Kunwadee Rangsriwatananon. All rights reserved.