Journal of Spectroscopy http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Study of Molecular and Ionic Vapor Composition over CeI3 by Knudsen Effusion Mass Spectrometry Mon, 05 Dec 2016 14:17:37 +0000 http://www.hindawi.com/journals/jspec/2016/2368131/ The molecular and ionic composition of vapor over cerium triiodide was studied by Knudsen effusion mass spectrometry. In the saturated vapor over CeI3 the monomer, dimer, and trimer molecules and the negative ions I−, , and were identified in the temperature range of 753–994 K. The partial pressures of CeI3, Ce2I6, and Ce3I9 were determined and the enthalpies of sublimation, (298.15 K) in kJ·mol−1, in the form of monomers (), dimers (), and trimers () were obtained by the second and third laws of thermodynamics. The enthalpy of formation, (298.15 K) in kJ·mol−1, of the CeI3 (), Ce2I6 (), and Ce3I9 () molecules and the () and () ions were calculated. The electron work function, =  eV, for the CeI3 crystal was evaluated. A. M. Dunaev, V. B. Motalov, L. S. Kudin, M. F. Butman, and K. W. Krämer Copyright © 2016 A. M. Dunaev et al. All rights reserved. XRD Investigation of Some Thermal Degraded Starch Based Materials Mon, 05 Dec 2016 14:14:27 +0000 http://www.hindawi.com/journals/jspec/2016/9605312/ The thermal degradation of some starch based materials was investigated using XRD method. The samples were obtained by thermal extrusion of mixtures of different proportions of starch, glycerol, and water. Such materials are suitable for the manufacturing of low pollutant packaging. Thermal degradation is one of the simplest ways to destroy such materials and this process is followed by structural modification of the local ordering of samples, water evaporation, crystallization, oxidation, or destruction of the chemical bonds. These modifications need to be studied in order to reduce to the minimum production of pollutant residues by burning process. XRD measurements show modification of the local ordering of the starch molecules depending on the temperature and initial composition of the samples. The molecular ordering perturbation is more pronounced in samples with low content of starch. Mihai Todica, Elena Mihaela Nagy, Carmen Niculaescu, Oana Stan, Nicolae Cioica, and Cornel Viorel Pop Copyright © 2016 Mihai Todica et al. All rights reserved. Quantitative Classification of Quartz by Laser Induced Breakdown Spectroscopy in Conjunction with Discriminant Function Analysis Sun, 04 Dec 2016 12:47:32 +0000 http://www.hindawi.com/journals/jspec/2016/1835027/ A responsive laser induced breakdown spectroscopic system was developed and improved for utilizing it as a sensor for the classification of quartz samples on the basis of trace elements present in the acquired samples. Laser induced breakdown spectroscopy (LIBS) in conjunction with discriminant function analysis (DFA) was applied for the classification of five different types of quartz samples. The quartz plasmas were produced at ambient pressure using Nd:YAG laser at fundamental harmonic mode (1064 nm). We optimized the detection system by finding the suitable delay time of the laser excitation. This is the first study, where the developed technique (LIBS+DFA) was successfully employed to probe and confirm the elemental composition of quartz samples. A. Ali, M. Z. Khan, I. Rehan, K. Rehan, and R. Muhammad Copyright © 2016 A. Ali et al. All rights reserved. Raman Spectroscopy in Colorectal Cancer Diagnostics: Comparison of PCA-LDA and PLS-DA Models Mon, 28 Nov 2016 12:38:18 +0000 http://www.hindawi.com/journals/jspec/2016/1603609/ Raman spectra of human colorectal tissue samples were employed to diagnose colorectal cancer. High-quality Raman spectra were acquired from normal and cancerous colorectal tissues from 81 patients. Subtle Raman variations, such as for peaks at 1134 cm−1 (protein, C-C/C-N stretching) and 1297 cm−1 (lipid, C-H2 twisting), were observed between normal and cancerous colorectal tissues. The average peak intensity at 1134 and 1297 cm−1 was increased from approximately 235 and 72 in the normal group, respectively, to 315 and 273 in the cancer group. The variations of Raman spectra reflected the changes of cell molecules during canceration. The multivariate statistical methods of principal component analysis-linear discriminant analysis (PCA-LDA) and partial least-squares-discriminant analysis (PLS-DA), together with leave-one-patient-out cross-validation, were employed to build the discrimination model. PCA-LDA was used to evaluate the capability of this approach for classifying colorectal cancer, resulting in a diagnostic accuracy of 79.2%. Further PLS-DA modeling yielded a diagnostic accuracy of 84.3% for colorectal cancer detection. Thus, the PLS-DA model is preferable between the two to discriminate cancerous from normal tissues. Our results demonstrate that Raman spectroscopy can be used with an optimized multivariate data analysis model as a sensitive diagnostic alternative to identify pathological changes in the colon at the molecular level. Wenjing Liu, Zhaotian Sun, Jinyu Chen, and Chuanbo Jing Copyright © 2016 Wenjing Liu et al. All rights reserved. Investigation by Raman Spectroscopy of the Decomposition Process of HKUST-1 upon Exposure to Air Mon, 28 Nov 2016 08:08:51 +0000 http://www.hindawi.com/journals/jspec/2016/8074297/ We report an experimental investigation by Raman spectroscopy of the decomposition process of Metal-Organic Framework (MOF) HKUST-1 upon exposure to air moisture ( K, 70% relative humidity). The data collected here are compared with the indications obtained from a model of the process of decomposition of this material proposed in literature. In agreement with that model, the reported Raman measurements indicate that for exposure times longer than 20 days relevant irreversible processes take place, which are related to the occurrence of the hydrolysis of Cu-O bonds. These processes induce small but detectable variations of the peak positions and intensities of the main Raman bands of the material, which can be related to Cu-Cu, Cu-O, and O-C-O stretching modes. The critical analyses of these changes have permitted us to obtain a more detailed description of the process of decomposition taking place in HKUST-1 upon interaction with moisture. Furthermore, the reported Raman data give further strong support to the recently proposed model of decomposition of HKUST-1, contributing significantly to the development of a complete picture of the properties of this considerable deleterious effect. Michela Todaro, Antonino Alessi, Luisa Sciortino, Simonpietro Agnello, Marco Cannas, Franco Mario Gelardi, and Gianpiero Buscarino Copyright © 2016 Michela Todaro et al. All rights reserved. Ultraviolet Spectroscopy Used to Fingerprint Five Wild-Grown Edible Mushrooms (Boletaceae) Collected from Yunnan, China Wed, 16 Nov 2016 07:53:34 +0000 http://www.hindawi.com/journals/jspec/2016/7813405/ Nowadays, wild-grown edible mushrooms which are natural, nutritious, and healthy get more and more popular by large consumers. In this paper, UV spectra of different Boletaceae mushrooms with the aid of partial least squares discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA) were shown to be a practical and rapid method for discrimination purpose. The specimens of Boletus edulis, Boletus ferrugineus, Boletus tomentipes, Leccinum rugosiceps, and Xerocomus sp. were described based on the UV spectra. From the results, all the specimens were characterized by strong absorption at the wavelengths of 274 and 284 nm and showed the shoulder at 296 nm. However, changes could be seen in the peak heights at the same wavelength for different samples. After analyzing by chemometrics, visual discrimination among samples was presented and the relationships among them were also obtained. This study showed that UV spectroscopy combined with chemometrics methods could be used successfully as a simple and effective approach for characterization of these five wild-grown edible mushrooms at species and genus levels. Meanwhile, this rapid and simple methodology could also provide reference for the discrimination of edible mushrooms. Yan Li, Ji Zhang, Tao Li, Tianwei Yang, Yuanzhong Wang, and Honggao Liu Copyright © 2016 Yan Li et al. All rights reserved. Solid-State 13C NMR Spectroscopy Applied to the Study of Carbon Blacks and Carbon Deposits Obtained by Plasma Pyrolysis of Natural Gas Wed, 16 Nov 2016 06:18:33 +0000 http://www.hindawi.com/journals/jspec/2016/1543273/ Solid-state 13C nuclear magnetic resonance (NMR) spectroscopy was used in this work to analyze the physical and chemical properties of plasma blacks and carbon deposits produced by thermal cracking of natural gas using different types of plasma reactors. In a typical configuration with a double-chamber reactor, N2 or Ar was injected as plasma working gas in the first chamber and natural gas was injected in the second chamber, inside the arc column. The solid residue was collected at different points throughout the plasma apparatus and analyzed by 13C solid-state NMR spectroscopy, using either cross polarization (CP) or direct polarization (DP), combined with magic angle spinning (MAS). The 13C CP/MAS NMR spectra of a number of plasma blacks produced in the N2 plasma reactor showed two resonance bands, broadly identified as associated with aromatic and aliphatic groups, with indication of the presence of oxygen- and nitrogen-containing groups in the aliphatic region of the spectrum. In contrast to DP experiments, only a small fraction of 13C nuclei in the plasma blacks are effectively cross-polarized from nearby 1H nuclei and are thus observed in spectra recorded with CP. 13C NMR spectra are thus useful to distinguish between different types of carbon species in plasma blacks and allow a selective study of groups spatially close to hydrogen in the material. Jair C. C. Freitas, Daniel F. Cipriano, Carlos G. Zucolotto, Alfredo G. Cunha, and Francisco G. Emmerich Copyright © 2016 Jair C. C. Freitas et al. All rights reserved. Quantitative Estimating Salt Content of Saline Soil Using Laboratory Hyperspectral Data Treated by Fractional Derivative Thu, 10 Nov 2016 13:13:21 +0000 http://www.hindawi.com/journals/jspec/2016/1081674/ Most present researches on estimation of soil salinity by hyperspectral data have focused on the spectral reflectance or their integer derivatives but ignored the fractional derivative information of hyperspectral data. Motivated by this situation, the selected study area is the Ebinur Lake basin located in the southwest border in the Xinjiang Uygur Autonomous Region, China, with severe salinization. The field work was conducted from 15 to 25 October, 2014, and a total of 180 soil samples were collected from 45 sampling sites; after measuring the soil salt content and spectral reflectance in the laboratory, the range from 0 to 2 was divided into 11 orders (interval 0.2) and then the hyperspectral data were treated by 4 kinds of mathematical transformations and 11 orders of fractional derivatives. Combined with the soil salt content, partial least square regression method was applied for model calibrations and predictions and some indexes were used to evaluate the performance of models. The results showed that the retrieval model built up by 250 bands based on 1.2-order derivative of 1/ had excellent capacity of estimating soil salt content in the study area ( g/kg,  g/kg, , , and RPD = 2.080). This study provides an application reference for quantitative estimations of other land surface parameters and some other applications on hyperspectral technology. Dong Zhang, Tashpolat Tiyip, Jianli Ding, Fei Zhang, Ilyas Nurmemet, Ardak Kelimu, and Jingzhe Wang Copyright © 2016 Dong Zhang et al. All rights reserved. Speciation in Solutions of Lithium Salts in Dimethyl Sulfoxide, Propylene Carbonate, and Dimethyl Carbonate from Raman Data: A Minireview Sun, 06 Nov 2016 09:59:05 +0000 http://www.hindawi.com/journals/jspec/2016/6978560/ Our recent Raman studies of cation and anion solvation and ion pairing in solutions of lithium salts in dimethyl sulfoxide, propylene carbonate, and dimethyl carbonate are briefly overviewed. Special attention is paid to differences in our and existing data and concepts. As follows from our results, cation solvation numbers in solutions are low (~2) and disagree with previous measurements. This discrepancy is shown to arise from correct accounting for dimerization, hydrogen bonding, and conformation equilibria in the solvents disregarded in early studies. Another disputable question touches upon the absence of free ions in solutions of lithium salts in carbonate solvents and the statement that the charge transfer in carbonate solutions is caused by SSIPs. Direct proofs of the nature of charge carriers in the solvents studied have been obtained by means of analyses of vibrational dynamics. It has been found that collision times for free anions are short and evidence weak interactions between anions and solvent molecules. In SSIPs, collision times are an order of magnitude longer thus signifying strong interactions between anions and cations. In CIPs, collision times become shorter than in SSIPs reflecting the transformation of the structure of concentrated solutions to that of molten salts. M. I. Gorobets, M. B. Ataev, M. M. Gafurov, and S. A. Kirillov Copyright © 2016 M. I. Gorobets et al. All rights reserved. Rapid Detection of Tetracycline Residues in Duck Meat Using Surface Enhanced Raman Spectroscopy Wed, 02 Nov 2016 11:04:55 +0000 http://www.hindawi.com/journals/jspec/2016/1845237/ A rapid detection method based on surface enhanced Raman spectroscopy (SERS) was proposed in this paper in order to realize the detection of tetracycline residues in duck meat. Firstly, surface enhanced Raman spectra characteristics of tetracycline aqueous solution, duck meat extract, and duck meat extract containing tetracycline were analyzed. Secondly, the effect of the addition amount of duck meat extract containing tetracycline on SERS intensity and the effect of the adsorption time on SERS intensity were discussed, respectively. Thirdly, SERS intensity ratio at 1272 and 1558 cm−1 () was used to establish the SERS calibration curve. A good linearity relationship between the tetracycline concentration in duck meat extract and was obtained, and the linear regression equation and the correlation coefficient () were and 0.950, respectively. The average recovery of tetracycline in duck meat extract was 101~108% with relative standard deviation (RSD) of 2.4~4.6%. The experimental results showed that the method proposed in this paper was a good detection scheme for the rapid detection of tetracycline residues in duck meat. Jinhui Zhao, Ping Liu, Haichao Yuan, Yijie Peng, Qian Hong, and Muhua Liu Copyright © 2016 Jinhui Zhao et al. All rights reserved. Optical Properties of DMA-π-DCV Derivatives: A Theoretical Inspection under the DFT Microscope Tue, 01 Nov 2016 07:02:57 +0000 http://www.hindawi.com/journals/jspec/2016/3520698/ The optical properties of a series of donor-acceptor N,N-dimethylaniline-π-dicyanovinylene (DMA-π-DCV) chromophores have been investigated under the density functional theory framework. Focus has been made on the low-lying charge-transfer (CT) electronic transitions for which experimental data is available. The effect of the π-conjugated bridge length and type was analysed between the families of oligoene and oligoyne derivatives of increasing size. Theoretical calculations demonstrate that the ethylene bridge is a better π-communicator and allows for more delocalized frontier molecular orbitals compared to the acetylene spacer. The diagnostic test allowed rationalization of the orbital spatial overlap in the main CT excitations. The performance of different density functional rungs was assessed in the prediction of the lowest-lying CT electronic transition. Surprisingly, most modern long-range corrected functionals demonstrated to provide among the largest errors, whereas hybrid functionals showed the best performance. Solvatochromism was confirmed in both oligoene and oligoyne compounds. A donor-acceptor-donor triad based on tetrathiafulvalene was utilised as a test system for the prediction of its two CT bands of different nature, energy, and intensity. The hybrid PBE0 (or a similar hybrid analogue) consolidates as the best choice for the prediction of CT excitations in the DMA-π-DCV push-pull family. Joaquín Calbo Copyright © 2016 Joaquín Calbo. All rights reserved. Spectral Quantitative Analysis Model with Combining Wavelength Selection and Topology Structure Optimization Wed, 19 Oct 2016 12:46:49 +0000 http://www.hindawi.com/journals/jspec/2016/5616503/ Spectroscopy is an efficient and widely used quantitative analysis method. In this paper, a spectral quantitative analysis model with combining wavelength selection and topology structure optimization is proposed. For the proposed method, backpropagation neural network is adopted for building the component prediction model, and the simultaneousness optimization of the wavelength selection and the topology structure of neural network is realized by nonlinear adaptive evolutionary programming (NAEP). The hybrid chromosome in binary scheme of NAEP has three parts. The first part represents the topology structure of neural network, the second part represents the selection of wavelengths in the spectral data, and the third part represents the parameters of mutation of NAEP. Two real flue gas datasets are used in the experiments. In order to present the effectiveness of the methods, the partial least squares with full spectrum, the partial least squares combined with genetic algorithm, the uninformative variable elimination method, the backpropagation neural network with full spectrum, the backpropagation neural network combined with genetic algorithm, and the proposed method are performed for building the component prediction model. Experimental results verify that the proposed method has the ability to predict more accurately and robustly as a practical spectral analysis tool. Qian Wang, Boyan Cai, Yajie Yu, and Hui Cao Copyright © 2016 Qian Wang et al. All rights reserved. Detection of Melamine in Soybean Meal Using Near-Infrared Microscopy Imaging with Pure Component Spectra as the Evaluation Criteria Tue, 18 Oct 2016 08:15:12 +0000 http://www.hindawi.com/journals/jspec/2016/5868170/ Soybean meal was adulterated with melamine with the purpose of boosting the protein content for unlawful interests. In recent years, the near-infrared (NIR) spectroscopy technique has been widely used for guaranteeing food and feed security for its fast, nondestructive, and pollution-free characteristics. However, there are problems with using near-infrared (NIR) spectroscopy for detecting samples with low contaminant concentration because of instrument noise and sampling issues. In addition, methods based on NIR are indirect and depend on calibration models. NIR microscopy imaging offers the opportunity to investigate the chemical species present in food and feed at the microscale level (the minimum spot size is a few micrometers), thus avoiding the problem of the spectral features of contaminants being diluted by scanning. The aim of this work was to investigate the feasibility of using NIR microscopy imaging to identify melamine particles in soybean meal using only the pure component spectrum. The results presented indicate that using the classical least squares (CLS) algorithm with the nonnegative least squares (NNLS) algorithm, without needing first to develop a calibration model, could identify soybean meal that is both uncontaminated and contaminated with melamine particles at as low a level as 50 mg kg−1. Zengling Yang, Lujia Han, Chengte Wang, Jing Li, Juan A. Fernández Pierna, Pierre Dardenne, and Vincent Baeten Copyright © 2016 Zengling Yang et al. All rights reserved. Photoreflectance and Raman Study of Surface Electric States on AlGaAs/GaAs Heterostructures Sun, 16 Oct 2016 07:52:31 +0000 http://www.hindawi.com/journals/jspec/2016/4601249/ Photoreflectance (PR) and Raman are two very useful spectroscopy techniques that usually are used to know the surface electronic states in GaAs-based semiconductor devices. However, although they are exceptional tools there are few reports where both techniques were used in these kinds of devices. In this work, the surface electronic states on AlGaAs/GaAs heterostructures were studied in order to identify the effect of factors like laser penetration depth, cap layer thickness, and surface passivation over PR and Raman spectra. PR measurements were performed alternately with two lasers (532 nm and 375 nm wavelength) as the modulation sources in order to identify internal and surface features. The surface electric field calculated by PR analysis decreased whereas the GaAs cap layer thickness increased, in good agreement with a similar behavior observed in Raman measurements ( ratio). When the heterostructures were treated by Si-flux, these techniques showed contrary behaviors. PR analysis revealed a diminution in the surface electric field due to a passivation process whereas the ratio did not present the same behavior because it was dominated by the depletion layers width (cap layer thickness) and the laser penetration depth. Luis Zamora-Peredo, Leandro García-González, Julián Hernández-Torres, Irving E. Cortes-Mestizo, Víctor H. Méndez-García, and Máximo López-López Copyright © 2016 Luis Zamora-Peredo et al. All rights reserved. Construction of Spectral Discoloration Model for Red Lead Pigment by Aging Test and Simulating Degradation Experiment Thu, 01 Sep 2016 16:05:05 +0000 http://www.hindawi.com/journals/jspec/2016/3517496/ The construction of spectral discoloration model, based on aging test and simulating degradation experiment, was proposed to detect the aging degree of red lead pigment in ancient murals and to reproduce the spectral data supporting digital restoration of the ancient murals. The degradation process of red lead pigment under the aging test conditions was revealed by X-ray diffraction, scanning electron microscopy, and spectrophotometer. The simulating degradation experiment was carried out by proportionally mixing red lead and lead dioxide with referring to the results of aging test. The experimental result indicated that the pure red lead was gradually turned into black lead dioxide, and the amount of tiny particles of the aging sample increased faced with aging process. Both the chroma and lightness of red lead pigment decreased with discoloration, and its hue essentially remains unchanged. In addition, the spectral reflectance curves of the aging samples almost started rising at about 550 nm with the inflection moving slightly from about 570 nm to 550 nm. The spectral reflectance of samples in long- and in short-wavelength regions was fitted well with the logarithmic and linear function. The spectral discoloration model was established, and the real aging red lead pigment in Dunhuang murals was measured and verified the effectiveness of the model. Jinxing Liang, Xiaoxia Wan, Chan Li, Junfeng Li, Qiang Liu, and Qian Cao Copyright © 2016 Jinxing Liang et al. All rights reserved. Fourier Transform Infrared Spectroscopy of “Bisphenol A” Tue, 23 Aug 2016 14:24:18 +0000 http://www.hindawi.com/journals/jspec/2016/2073613/ FTIR (400–4000 cm−1) spectra of “Bisphenol A” are presented. Absorption peaks (400–4000 cm−1) are assigned on the basis of Density Functional Theory (DFT) with configuration as B3LYP 6-311G++ (3df 3pd). Calculated absorption peaks are in reasonable reconciliation with experimental absorption peaks after scaling with scale factor of 0.9679 except C-H and O-H stretching vibrations. Ramzan Ullah, Ishaq Ahmad, and Yuxiang Zheng Copyright © 2016 Ramzan Ullah et al. All rights reserved. Spectroscopic Investigations of the Oxidative Polymerization of Hydroquinone in the Presence of Hexavalent Chromium Mon, 22 Aug 2016 14:11:36 +0000 http://www.hindawi.com/journals/jspec/2016/7958351/ Polyphenol polymerization receives much scientific attentions because it is an important reaction of humification processes. Through an oxidative polymerization reaction (OPR), hydroquinone (H2Q), a naturally occurring compound, has been found to be a vital precursor of humic substances in soils. Chromate (Cr(VI)), a strong oxidant, is widely distributed in the environment due to the inappropriate disposal of Cr-containing wastes. The OPR of H2Q in the presence of Cr(VI) may occur naturally. In the study, it was found that 400 mg L−1 H2Q could be polymerized at pH 3.0 with 105 mg L−1 Cr(VI). The results of FT-IR revealed the presence of both hydroquinone and benzoquinone nuclei in the polymer. The spectra of X-ray absorption near edge structure (XANES) demonstrated a decrease in Cr(VI) content during the OPR of H2Q. Based on the results of linear combination fitting (LCF) for the spectra of XANES, the proportions of Cr species in the precipitates mainly consisted of Cr(OH)3, and Cr-carboxylate contents increased gradually from 15.3 to 25.5% over the reaction time. After acidizing the supernatants at pH 1.0 for 1 d, Cr(III)-HA dominated Cr(III) species. This suggested that humic-like substances were formed during OPR of H2Q, possibly through the formation of Cr(III)-organic complex. Ching-Yun Cheng, Ya-Ting Chan, Yu-Min Tzou, Kai-Yue Chen, and Yu-Ting Liu Copyright © 2016 Ching-Yun Cheng et al. All rights reserved. Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies Sun, 14 Aug 2016 13:43:42 +0000 http://www.hindawi.com/journals/jspec/2016/7520741/ Recently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal of the oxide groups can create vacancies and structural defects, reduced graphene oxide (rGO) is used in composites as effective filler similar to GO. Authors developed a new polyurethane nanocomposite using a derivative of grapheme, thermally reduced graphene oxide (rGO), to modify the matrix of polyurethane elastomers, by rGO. Michał Strankowski, Damian Włodarczyk, Łukasz Piszczyk, and Justyna Strankowska Copyright © 2016 Michał Strankowski et al. All rights reserved. Diagnosis of High Voltage Insulators Made of Ceramic Using Spectrophotometry Sun, 14 Aug 2016 11:51:11 +0000 http://www.hindawi.com/journals/jspec/2016/9548302/ The paper presents results of comparative analysis of optical signals emitted by partial discharges occurring on three types of high voltage insulators made of porcelain. The research work consisted of diagnosis of the following devices: a long rod insulator, a cap insulator, and an insulating cylinder. For optical signal registration a spectrophotometer was applied. All measurements were performed under laboratory conditions by changing the value of partial discharges generation voltage. For the cylindrical insulator also the distance between high voltage and ground electrodes was subjected for investigation as a factor having influence on partial discharges. The main contribution which resulted from the studies is statement that application of spectrophotometer enables faster recognition of partial discharges, as compared to standard methods. Paweł Frącz, Ireneusz Urbaniec, Tomasz Turba, and Sławomir Krzewiński Copyright © 2016 Paweł Frącz et al. All rights reserved. Relation between Silver Nanoparticle Formation Rate and Antioxidant Capacity of Aqueous Plant Leaf Extracts Sun, 31 Jul 2016 14:08:59 +0000 http://www.hindawi.com/journals/jspec/2016/4083421/ Correlation between the antioxidant capacity and silver nanoparticle formation rates of pomegranate (Punica granatum), quince (Cydonia oblonga), chestnut (Castanea sativa), fig (Ficus carica), walnut (Juglans cinerea), black mulberry (Morus nigra), and white mulberry (Morus alba) leaf extracts is investigated at a fixed illumination. Silver nanoparticles formed in all plant leaf extracts possess round shapes with average particle size of 15 to 25 nm, whereas corresponding surface plasmon resonance peak wavelengths vary between 422 nm and 451 nm. Cupric reducing antioxidant capacity technique is used as a reference method to determine total antioxidant capacity of the plant leaf extracts. Integrated absorbance over the plasmon resonance peaks exhibits better linear relation with antioxidant capacities of various plant leaf extracts compared to peak absorbance values, with correlation coefficient values of 0.9333 and 0.7221, respectively. Azat Akbal, M. Haluk Turkdemir, Ahmet Cicek, and Bulent Ulug Copyright © 2016 Azat Akbal et al. All rights reserved. Recent Advances in Optical Spectroscopic and Imaging Methods for Medicine and Biology Wed, 27 Jul 2016 12:20:34 +0000 http://www.hindawi.com/journals/jspec/2016/4095790/ Yu Shang, Zhiyu Qian, Rickson C. Mesquita, and Mathieu Dehaes Copyright © 2016 Yu Shang et al. All rights reserved. Combining Near-Infrared Spectroscopy and Chemometrics for Rapid Recognition of an Hg-Contaminated Plant Tue, 26 Jul 2016 08:39:49 +0000 http://www.hindawi.com/journals/jspec/2016/3597451/ The feasibility of rapid recognition of an Hg-contaminated plant as a soil pollution indicator was investigated using near-infrared spectroscopy (NIRS) and chemometrics. The stem and leave of a native plant, Miscanthus floridulus (Labill.) Warb. (MFLW), were collected from Hg-contaminated areas () as well as from regular areas (). The samples were dried and crushed and the powders were sieved through an 80-mesh sieve. Reference analysis of Hg levels was performed using inductively coupled plasma-atomic emission spectrometry (ICP-AES). The actual Hg contents of contaminated and normal samples were 16.2–30.5 and 0.0–0.1 mg/Kg, respectively. The NIRS measurements of impacted sample powders were collected in the mode of reflectance. The DUPLEX algorithm was utilized to split the NIRS data into representative training and test sets. Different spectral preprocessing methods were performed to remove the unwanted and noncomposition-correlated spectral variations. Classification models were developed using partial least squares discrimination analysis (PLSDA) based on the raw, smoothed, second-order derivative (D2), and standard normal variate (SNV) data, respectively. The prediction accuracy obtained by PLSDA with each data preprocessing option was 100%, indicating pattern recognition of Hg-contaminated MFLW samples using NIRS data was in perfect consistence with the ICP-AES results. NIRS combined with chemometrics will provide a tool to screen the Hg-contaminated MFLW, which can be potentially used as an indicator of soil pollution. Bang-Cheng Tang, Hai-Yan Fu, Qiao-Bo Yin, Zeng-Yan Zhou, Wei Shi, Lu Xu, and Yuan-Bin She Copyright © 2016 Bang-Cheng Tang et al. All rights reserved. Kinetic Parameters during Bis-GMA and TEGDMA Monomer Polymerization by ATR-FTIR: The Influence of Photoinitiator and Light Curing Source Mon, 25 Jul 2016 11:41:08 +0000 http://www.hindawi.com/journals/jspec/2016/6524901/ This study aimed to analyze the kinetic parameters of two monomers using attenuated total reflectance Fourier transform infrared (ATR-FTIR): 2,2-bis-[4-(2-hydroxy-3-methacryloxypropyl-1-oxy)-phenyl] propane (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA). The following were calculated to evaluate the kinetic parameters: maximum conversion rate (), time at the maximum polymerization rate (), conversion at , and total conversion recorded at the maximum conversion point after 300 s. Camphorquinone (CQ) and phenyl propanedione (PPD) were used in this study as photoinitiators, whereas N,N-dimethyl-p-toluidine (DMPT) amine was used as a coinitiator. LED apparatus and halogen lamp were used in turn to evaluate the effect that light source had on the monomer kinetics. The mass concentration ratio for the three resin preparations was 0.7 : 0.3 for Bis-GMA and TEGDMA: R1 (CQ + DMPT), R2 (PPD + DMPT), and R3 (PPD + CQ + DMPT). The PPD association with the CQ photoinitiator altered the polymerization kinetics compared to a resin containing only the CQ photoinitiator. The light sources exhibited no significant differences for of R1 and R3. Resins containing only the PPD initiator exhibited a higher than those containing only CQ. However, the decreased for resins containing the PPD photoinitiator. Aline B. Denis, Cristina A. Diagone, Ana M. G. Plepis, and Rommel B. Viana Copyright © 2016 Aline B. Denis et al. All rights reserved. A Study of the Far Infrared Spectrum of N-Acetyl-D-Glucosamine Using THz-TDS, FTIR, and Semiempirical Quantum Chemistry Methods Wed, 13 Jul 2016 12:51:47 +0000 http://www.hindawi.com/journals/jspec/2016/4058478/ The far infrared spectrum of N-acetyl-D-glucosamine has been studied by combining THz–TDS and FTIR characterization techniques with theoretical studies based on semiempirical quantum chemistry methods. A strong spectral peak at 60 cm−1 has been identified, which constitutes the main signature of the material in the terahertz band. Calculated molecular vibrations are in good qualitative and semiquantitative agreement with both the THz-TDS and FTIR experiments. In comparison to previous DFT-based studies, the semiempirical approach chosen herein, suitable for parallel multi-core and GPU acceleration, allows for a full study using periodic boundary conditions and no further approximations within a constrained computing time. Pedro Chamorro-Posada, Iosody Silva-Castro, José Vázquez-Cabo, Pablo Martín-Ramos, José María López-Santos, and Jesús Martín-Gil Copyright © 2016 Pedro Chamorro-Posada et al. All rights reserved. Interaction of Fullerenes with Organosilanes in the Ionization Chamber of a Mass Spectrometer under Electron Impact and the Reaction of C60 with Tetraphenylsilane in Solution under UV Irradiation Tue, 28 Jun 2016 09:09:23 +0000 http://www.hindawi.com/journals/jspec/2016/8158623/ C60 was shown to react with organosilanes Me4Si, Ph2SiH2, Ph2MeSiH, Ph4Si, and α-naphthylphenylmethylsilane in the electron ionization ion source of a mass spectrometer with the transfer of the corresponding organic radicals (Me, Ph, and α-naphthyl) from the silanes to the fullerene. The reactions were accompanied by hydrogen addition to some products and hydrogen loss from them. C70 reacted with Me4Si analogously. A reaction mechanism involving homolytic dissociation of the silanes under electron impact to the corresponding organic radicals, which react further with C60 at the surface of the ionization chamber of the mass spectrometer to give the respective adducts, was offered. A mechanistic study of the reaction of C60 with Me4Si supported it. No silicon containing derivatives of the fullerenes were found. C60 reacted with Ph4Si in solution under UV irradiation in a similar fashion furnishing phenyl derivatives of the fullerene. These results provide an additional support to the hypothesis formulated earlier that the homolytic reactive mass spectrometry of fullerenes (the reactions of fullerenes with other species in the ionization chambers of mass spectrometers and their mass spectral monitoring) can predict the reactivity of them toward the same reagents in solution to a significant extent. Yury I. Lyakhovetsky, Elena A. Shilova, Alexandra P. Pleshkova, Alexander I. Belokon, Sergey O. Yakushin, and Boris L. Tumanskii Copyright © 2016 Yury I. Lyakhovetsky et al. All rights reserved. Applications of Spectroscopy in Environmental Monitoring of Gases and Aerosols Tue, 21 Jun 2016 07:06:25 +0000 http://www.hindawi.com/journals/jspec/2016/2575782/ Arnaud Cuisset, Dean S. Venables, Xiaoming Gao, and Hassen Aroui Copyright © 2016 Arnaud Cuisset et al. All rights reserved. Spectroscopic Investigations, DFT Calculations, and Molecular Docking Studies of the Anticonvulsant (2E)-2-[3-(1H-Imidazol-1-yl)-1-phenylpropylidene]-N-(4-methylphenyl)hydrazinecarboxamide Wed, 25 May 2016 11:10:53 +0000 http://www.hindawi.com/journals/jspec/2016/8520757/ Drug discovery for the management of neurological disorders is a challenging arena in medicinal chemistry. Vibrational spectral studies of (2E)-2-[3-(1H-imidazol-1-yl)-1-phenylpropylidene]-N-(4-methylphenyl)hydrazinecarboxamide ((2E)-IPPMP) have been recorded and analyzed to identify the functional groups and intermolecular/intramolecular interactions of the title molecule. The blue shift of the C-H stretching wavenumber reveals the presence of improper C-H⋯O hydrogen bonding. The equilibrium geometry, harmonic vibrational wavenumbers, Frontier orbital energy, and natural bond orbital analyses have been carried out using density functional theory with a B3LYP/6-311++G(d,p) level of the basis set. The vibrational modes have been unambiguously assigned using potential energy distribution analysis. The scaled wavenumbers are in good agreement with the experimental results. Natural bond orbital analysis has confirmed the intermolecular/intramolecular charge transfer interactions. HOMO-LUMO analysis was carried out to explore charge delocalization on the (2E)-IPPMP molecule. A molecular docking study has supported the anticonvulsant activity of the title molecule. Reem I. Al-Wabli, Devarasu Manimaran, Liji John, Isaac Hubert Joe, Nadia G. Haress, and Mohamed I. Attia Copyright © 2016 Reem I. Al-Wabli et al. All rights reserved. Background Radiance Estimation for Gas Plume Quantification for Airborne Hyperspectral Thermal Imaging Thu, 19 May 2016 09:48:29 +0000 http://www.hindawi.com/journals/jspec/2016/5428762/ Hyperspectral imaging in the long-wave infrared (LWIR) is a mean that is proving its worth in the characterization of gaseous effluent. Indeed the spectral and spatial resolution of acquisition instruments is steadily decreasing, making the gases characterization increasingly easy in the LWIR domain. The majority of literature algorithms exploit the plume contribution to the radiance corresponding to the difference of radiance between the plume-present and plume-absent pixels. Nevertheless, the off-plume radiance is unobservable using a single image. In this paper, we propose a new method to retrieve trace gas concentration from airborne infrared hyperspectral data. More particularly the outlined method improves the existing background radiance estimation approach to deal with heterogeneous scenes corresponding to industrial scenes. It consists in performing a classification of the scene and then applying a principal components analysis based method to estimate the background radiance on each cluster stemming from the classification. In order to determine the contribution of the classification to the background radiance estimation, we compared the two approaches on synthetic data and Telops Fourier Transform Spectrometer (FTS) Imaging Hyper-Cam LW airborne acquisition above ethylene release. We finally show ethylene retrieved concentration map and estimate flow rate of the ethylene release. Ramzi Idoughi, Thomas H. G. Vidal, Pierre-Yves Foucher, Marc-André Gagnon, and Xavier Briottet Copyright © 2016 Ramzi Idoughi et al. All rights reserved. Identification and Quantitation of Melamine in Milk by Near-Infrared Spectroscopy and Chemometrics Tue, 17 May 2016 12:57:11 +0000 http://www.hindawi.com/journals/jspec/2016/6184987/ Melamine is a nitrogen-rich substance and has been illegally used to increase the apparent protein content in food products such as milk. Therefore, it is imperative to develop sensitive and reliable analytical methods to determine melamine in human foods. Current analytical methods for melamine are mainly chromatography-based methods, which are time-consuming and expensive and require complex pretreatment and well-trained technicians. The present paper investigated the feasibility of using near-infrared (NIR) spectroscopy and chemometrics for identifying and quantifying melamine in liquor milk. A total of 75 samples were prepared. Uninformative variable elimination-partial least square (UVE-PLS) and partial least squares-discriminant analysis (PLS-DA) were used to construct quantitative and qualitative models, respectively. Based on the ratio of performance to standard deviate (RPD), UVE-PLS model with 3 components resulted in a better solution. The PLS-DA model achieved an accuracy of 100% and outperformed the optimal reference model of soft independent modeling of class analogy (SIMCA). Such a method can serve as a potential tool for rapid screening of melamine in milk products. Tong Wu, Hui Chen, Zan Lin, and Chao Tan Copyright © 2016 Tong Wu et al. All rights reserved. A Study of Structural and Photoluminescence for Al-Doped CdO Thin Films Sun, 15 May 2016 07:33:14 +0000 http://www.hindawi.com/journals/jspec/2016/5127348/ Al-doped CdO thin films were prepared by radio frequency magnetron sputtering at different deposition time and substrate temperature. X-ray diffraction showed that the changes in the intensities of the (200), (220), and (311) planes followed a similar trend with increase in deposition time. The surface of the thin film was examined by scanning electron microscopy. Grain sizes of Al-doped CdO thin films increased significantly with increasing deposition time. The film thicknesses were 0.09, 0.12, 0.20, and 0.225 μm for the deposition times of 1, 2, 3, and 4 h, respectively. The photoluminescence spectra of the Al-doped CdO thin films were measured at room temperature. The photoluminescence wavelength changed in the sequence, green, blue, green, and blue, with increasing deposition time, which indicates that blue light emitting films can be fabricated by adjusting the processing parameters. Bong Ju Lee and Jin Jeong Copyright © 2016 Bong Ju Lee and Jin Jeong. All rights reserved.