Journal of Spectroscopy http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Prospects on Time-Domain Diffuse Optical Tomography Based on Time-Correlated Single Photon Counting for Small Animal Imaging Wed, 10 Feb 2016 09:32:52 +0000 http://www.hindawi.com/journals/jspec/2016/1947613/ This paper discusses instrumentation based on multiview parallel high temporal resolution (<50 ps) time-domain (TD) measurements for diffuse optical tomography (DOT) and a prospective view on the steps to undertake as regards such instrumentation to make TD-DOT a viable technology for small animal molecular imaging. TD measurements provide information-richest data, and we briefly review the interaction of light with biological tissues to provide an understanding of this. This data richness is yet to be exploited to its full potential to increase the spatial resolution of DOT imaging and to allow probing, via the fluorescence lifetime, tissue biochemical parameters, and processes that are otherwise not accessible in fluorescence DOT. TD data acquisition time is, however, the main factor that currently compromises the viability of TD-DOT. Current high temporal resolution TD-DOT scanners simply do not integrate sufficient detection channels. Based on our past experience in developing TD-DOT instrumentation, we review and discuss promising technologies to overcome this difficulty. These are single photon avalanche diode (SPAD) detectors and fully parallel highly integrated electronics for time-correlated single photon counting (TCSPC). We present experimental results obtained with such technologies demonstrating the feasibility of next-generation multiview TD-DOT therewith. Yves Bérubé-Lauzière, Matteo Crotti, Simon Boucher, Seyedrohollah Ettehadi, Julien Pichette, and Ivan Rech Copyright © 2016 Yves Bérubé-Lauzière et al. All rights reserved. Synthesis and Luminescent Characteristics of Ce3+-Activated Borosilicate Blue-Emitting Phosphors for LEDs Mon, 01 Feb 2016 08:46:52 +0000 http://www.hindawi.com/journals/jspec/2016/9346503/ The phosphors Sr3B2SiO8:Ce3+ have been successfully synthesized via solid-state reaction process. Emission/excitation spectra and photoluminescence decay behaviors were investigated in detail. Under the excitation of 340 nm, the emission spectrum presented an asymmetry emission band extended from 350 to 600 nm, which with the main peak at 425 nm can be fitted in two peaks (23940 cm−1 and 21934 cm−1). The chromaticity coordinates of :Ce3+ are fixed in the blue region; when the intensity of Ce3+ reached the maximum, the chromaticity coordinate is (0.154, 0.088) which is more close to the standard CIE of blue light (0.140, 0.080). The results showed the kind of phosphor may have potential applications in the fields of UV-excited white LEDs. Hong Yu, Jinlei Chen, and Shucai Gan Copyright © 2016 Hong Yu et al. All rights reserved. Near-Infrared Spectroscopic Screening for Bladder Disease in Africa: Training Rural Clinic Staff to Collect Data of Diagnostic Quality Sun, 24 Jan 2016 14:15:14 +0000 http://www.hindawi.com/journals/jspec/2016/1241862/ Background. While near-infrared spectroscopy (NIRS) has recognized relevance for developing countries, biomedical applications are rare. This reflects the cost and complexity of NIRS and the convention of comprehensive training for accurate data collection. In an international initiative using transcutaneous NIRS to screen for bladder disease in Africa, we evaluated if interactive training enabled clinic staff to collect data accurately. Methods. Workshop training in a Ugandan medical clinic on NIRS monitoring theory; bladder physiology and chromophore changes occurring with disease; device orientation; device positioning over the bladder, monitoring subjects during voiding; and saving/uploading data. Participation in patient screening followed with observation, assistance, and then data collection. Evaluation comprised conduct of serial independent screenings with analysis if saved files were of diagnostic quality. Results. 10 individuals attended 1-hour workshops and then 0.5–3.0 hours of screening. Five then felt able to conduct screening independently and all collected data were of diagnostic quality (>5 consecutive patients); all had participated in screening for >1.5 hours (6+ subjects); less participation allowed competent assistance but not consistent adherence to the monitoring protocol. Conclusion. A simplified NIRS system, small-group theory/orientation workshops, and >I.5 hours of 1 : 1 training during screening enabled clinic staff in Africa to collect accurate NIRS data. Lynn Stothers, Andrew Macnab, Sharif Mutabazi, Ronald Mukisa, Behnam Molavi, and Babak Shadgan Copyright © 2016 Lynn Stothers et al. All rights reserved. Thickness Measurement of V2O5 Nanometric Thin Films Using a Portable XRF Sun, 24 Jan 2016 09:32:35 +0000 http://www.hindawi.com/journals/jspec/2016/9509043/ Nanometric thin films have always been chiefly used for decoration; however they are now being widely used as the basis of high technology. Among the various physical qualities that characterize them, the thickness strongly influences their properties. Thus, a new procedure is hereby proposed and developed for determining the thickness of V2O5 nanometric thin films deposited on the glass surface using Portable X-Ray Fluorescence (PXRF) equipment and the attenuation of the radiation intensity Kα of calcium present in the glass. It is shown through the present paper that the radiation intensity of calcium Kα rays is proportional to film thickness in nanometric films of vanadium deposited on the glass surface. Fabio Lopes, Luís Henrique Cardozo Amorin, Larissa da Silva Martins, Alexandre Urbano, Carlos Roberto Appoloni, and Roberto Cesareo Copyright © 2016 Fabio Lopes et al. All rights reserved. Fabrication and Crystallization of ZnO-SLS Glass Derived Willemite Glass-Ceramics as a Potential Material for Optics Applications Thu, 21 Jan 2016 13:12:07 +0000 http://www.hindawi.com/journals/jspec/2016/8084301/ Willemite glass-ceramics were successfully derived from conventional melt-quench ZnO-SLS precursor glass by an isothermal heat treatment process. The effect of heat treatment temperatures on the physical properties was investigated by Archimedes principle and linear shrinkage. The generation of willemite crystal phase and morphology with increase in heat treatment temperature was examined by X-ray diffraction (XRD), Fourier transform infrared (FTIR), and field emission scanning electron microscopy (FESEM) techniques. X-ray diffraction revealed that the metastable -Zn2SiO4 and thermodynamically stable zinc orthosilicate α-Zn2SiO4 phases can be observed at temperatures above 700°C. The experimental results indicated that the density and shrinkage of the glass-ceramic vary with increasing the sintering temperature. FTIR studies showed that the structure of glass-ceramic consists of SiO2 and ZnO4 units and exhibits the structural evolution of willemite glass-ceramics. The characteristic of strong vibrational bands can be related to the tetrahedron corresponding to reference spectra of willemite. Mohd Hafiz Mohd Zaid, Khamirul Amin Matori, Sidek Hj. Abdul Aziz, Halimah Mohamed Kamari, Wan Mahmood Mat Yunus, Zaidan Abdul Wahab, and Nur Farhana Samsudin Copyright © 2016 Mohd Hafiz Mohd Zaid et al. All rights reserved. Mid-Infrared Spectroscopy for Coffee Variety Identification: Comparison of Pattern Recognition Methods Wed, 20 Jan 2016 17:07:36 +0000 http://www.hindawi.com/journals/jspec/2016/7927286/ The potential of using mid-infrared transmittance spectroscopy combined with pattern recognition algorithm to identify coffee variety was investigated. Four coffee varieties in China were studied, including Typica Arabica coffee from Yunnan Province, Catimor Arabica coffee from Yunnan Province, Fushan Robusta coffee from Hainan Province, and Xinglong Robusta coffee from Hainan Province. Ten different pattern recognition methods were applied on the optimal wavenumbers selected by principal component analysis loadings. These methods were classified as highly effective methods (soft independent modelling of class analogy, support vector machine, back propagation neural network, radial basis function neural network, extreme learning machine, and relevance vector machine), methods of medium effectiveness (partial least squares-discrimination analysis, nearest neighbors, and random forest), and methods of low effectiveness (Naive Bayes classifier) according to the classification accuracy for coffee variety identification. Chu Zhang, Chang Wang, Fei Liu, and Yong He Copyright © 2016 Chu Zhang et al. All rights reserved. In Vivo Monitoring on Growth and Spread of Gray Leaf Spot Disease in Capsicum annuum Leaf Using Spectral Domain Optical Coherence Tomography Tue, 19 Jan 2016 13:42:12 +0000 http://www.hindawi.com/journals/jspec/2016/1093734/ We have demonstrated the application of optical coherence tomography (OCT) in diagnosis of growth and spread of the gray leaf spot disease in Capsicum annuum leaf caused by the fungus Stemphylium lycopersici. Using 2D cross-sectional and 3D volumetric images of OCT, in vivo study of layer differences between fungus infected leaves and healthy leaves was observed with distinctive features. We observed that the internal layers of the disease-affected parts of the leaf seem to merge forming a single thick layer. The obtained OCT results verify the noninvasive diagnosis ability of fungal growth and spread in Capsicum annuum leaves and the applicability of this methodology for other plant diseases. Naresh Kumar Ravichandran, Ruchire Eranga Wijesinghe, Muhammad Faizan Shirazi, Kibeom Park, Seung-Yeol Lee, Hee-Young Jung, Mansik Jeon, and Jeehyun Kim Copyright © 2016 Naresh Kumar Ravichandran et al. All rights reserved. Concomitant Use of Fourier Transform Infrared Attenuated Total Reflectance Spectroscopy and Chemometrics for Quantification of Multiple Adulterants in Roasted and Ground Coffee Mon, 18 Jan 2016 06:46:28 +0000 http://www.hindawi.com/journals/jspec/2016/4974173/ This paper proposed the joint use of Fourier Transform Infrared Attenuated Total Reflectance Spectroscopy (FTIR-ATR) and Partial Least Square (PLS) regression for the simultaneous quantification of four adulterants (coffee husks, spent coffee grounds, barley, and corn) in roasted and ground coffee. Roasted coffee samples were intentionally blended with the adulterants, at adulteration levels ranging from 0.5 to 66% w/w. A robust methodology was implemented in which the identification of outliers was carried out. High correlation coefficients (0.99 for both calibration and validation) coupled with low degrees of error (0.69% for calibration; 2.00% for validation) confirmed that FTIR-ATR can be a valuable analytical tool for quantification of adulteration in roasted and ground coffee. This method is simple, fast, and reliable for the proposed purpose. Nádia Reis, Adriana S. Franca, and Leandro S. Oliveira Copyright © 2016 Nádia Reis et al. All rights reserved. Depth-Sensitive Raman Investigation of Metal-Oxide-Semiconductor Structures: Absorption as a Tool for Variation of Exciting Light Penetration Depth Tue, 12 Jan 2016 06:08:23 +0000 http://www.hindawi.com/journals/jspec/2016/1617063/ Presented work focuses the attention on two regions of MOS structure placed in the vicinity of the semiconductor/dielectric interface, in particular: on part of dielectric layer and thin layer of the substrate. In the presented work the application of absorption as a tool that can vary the absorption depth of excitation light into the semiconductor substrate is discussed. The changes of the absorption depth of visible light allows to obtain Raman signal from places in the substrate placed at different distances from the dielectric/semiconductor interface. The series of Raman spectra obtained from visible excitation in the case of varying absorption depth allowed to analyze the structure of the substrate as a function of distance from the interface. Deep ultraviolet Raman study regarding part of silicon dioxide layer placed directly at the interface is not discussed so far which makes the analysis of the structure of this part of dielectric layer possible. Comparison of reported in this work Raman data with structure of silicon/silicon dioxide interface obtained from other experimental techniques proves the applicability of proposed methodology. Paweł Borowicz Copyright © 2016 Paweł Borowicz. All rights reserved. Portable Gas Analyzer Based on Fourier Transform Infrared Spectrometer for Patrolling and Examining Gas Exhaust Wed, 30 Dec 2015 09:05:49 +0000 http://www.hindawi.com/journals/jspec/2015/136516/ Aimed at monitoring emission of organic gases such as CH4, C2H6, C3H8, iso-C4H10, n-C4H10, C2H4, C3H6, C2H2, CO, and CO2, from coal mines, petroleum refineries, and other plants, a Fourier Transform Infrared (FT-IR) spectrometer was used to develop a portable gas analyzer for patrolling and examining gas exhaust. Firstly, structure of the instrument was introduced. Then, a spectral analysis approach was presented. Finally, instrument was tested with standard gases and with actual gases emitted from a petroleum refinery. For the latter test, a gas chromatograph (GC) was used as a reference instrument. The test results showed that the detection limit of every component of analyte was less than 10 × 10−6. The maximum test error of every analyte was less than 15 × 10−6 when its practical concentration was no more than 500 × 10−6. A final comparison showed that the result curves of analytes obtained with FT-IR spectrometer almost overlapped with those obtained with GC, and their resulting noise was less than 6.4% when the practical gas concentration was above 100 × 10−6. As a result, our instrument was suitable to be used as a portable instrument for monitoring exhaust gases. Yuntao Liang, Xiaojun Tang, Xuliang Zhang, Fuchao Tian, Yong Sun, and Haozhe Dong Copyright © 2015 Yuntao Liang et al. All rights reserved. Atmospheric Aerosols Detection Research with a Dual Field of View Lidar Wed, 30 Dec 2015 06:27:26 +0000 http://www.hindawi.com/journals/jspec/2015/459460/ A dual field of view lidar system with two independent receivers is described to realize the detection of atmospheric aerosols. A CCD camera is attached to a backscatter lidar as a receiver to complement the data in the near-field range affected by the incomplete overlap between the laser beam and the receiver field of view. The signal detected by the CCD camera is corrected and finally glued with the signal of the backscatter lidar to retrieve the aerosol extinction coefficient with Fernald algorithm. The aerosol extinction profile and visibilities measured by the dual field of lidar had been compared with the results measured by another general backscatter lidar and a surface aerosol instrument, respectively. The results suggested that the dual field of view lidar based on a CCD camera is feasible and reliable. It could obtain the data both in the near and in the far range simultaneously, improving the detection accuracy of the lidar system effectively. Lv Lihui, Zhang Tianshu, Liu Cheng, Dong Yunsheng, Chen Zhenyi, Fan Guangqiang, Liu Yang, and Liu Wenqing Copyright © 2015 Lv Lihui et al. All rights reserved. One and Multiple Bonds Interatomic Spin-Spin Coupling in η6-Cymene Ru(II) of 3,5-Dimethyl-, 3,5-Dicarboxylic-, and 5-Phenyl-pyrazole Derivatives Tue, 29 Dec 2015 08:12:48 +0000 http://www.hindawi.com/journals/jspec/2015/832045/ The changes in the interatomic distances and the corresponding spin-spin coupling as a result of the hydrolysis of the ruthenium complexes and the effects of different derivatives of the pyrazole ligands and the substituents methyl, carboxylic, and phenyl on the pyrazole rings were studied. A good agreement was obtained between the experimental and the theoretical proton NMR. Significant changes are observed in the isotropic and anisotropic shielding tensor of the atoms and related spin-spin coupling of their bonds due to hydrolysis of the complexes. This observation gives more insight into the known mechanism of activation of the ruthenium complexes by hydrolysis. There are no direct effects of interatomic distances on many of the computed spin-spin couplings with the exception of 1J(Ru-N) which shows significant changes especially within the pair of 1J(Ru-N) in the complexes with two nitrogen atoms of the bis-pyrazole moiety. The magnitude of interatomic spin-spin coupling of the Ru-X follows the order of Ru-Cl > Ru-N > Ru-C > Ru-O. The Ramsey term Fermi contact (FC) has the most significant contribution in most of the computed spin-spin interactions except in 1J(Ru-Cl) and 1J() which are predominantly defined by the contribution from the paramagnetic spin orbit (PSO). Adebayo A. Adeniyi and Peter A. Ajibade Copyright © 2015 Adebayo A. Adeniyi and Peter A. Ajibade. All rights reserved. Enhancement of UV Excited Photoluminescence by Fabry-Perot Microcavity Tue, 22 Dec 2015 13:50:46 +0000 http://www.hindawi.com/journals/jspec/2015/153483/ A light-emitting microcavity with the structure of dielectric mirror/phosphor coating/dielectric mirror for the enhancement of PL efficiency excited under UV light was designed and fabricated. The fluorescence emission of Lumogen S0795 coating within microcavity structure is significantly enhanced compared with the coating on bare substrate. The measurement results indicate the possibility of developing front illuminated CCD based on optical resonant cavity for UV-visible imaging with higher sensitivity. Chunxian Tao, Jun Ruan, Dong Liang, Zhaoxia Han, Liang He, Ruijin Hong, Xiao Cui, and Dawei Zhang Copyright © 2015 Chunxian Tao et al. All rights reserved. Multi-Quartz Enhanced Photoacoustic Spectroscopy with Different Acoustic Microresonator Configurations Sun, 20 Dec 2015 12:49:27 +0000 http://www.hindawi.com/journals/jspec/2015/218413/ Acoustic microresonators were added to the recently developed multi-QTF based QEPAS spectrophone to enhance the signal amplitude. Two kinds of “on-beam” configurations were experimentally investigated in detail. The developed multi-QTF based “on-beam” spectrophone had a signal enhancement of 1.6 times compared with the traditional single QTF based “on-beam” spectrophone, with the approximate noise level. A normalized noise equivalent absorption coefficient () of 1.24 × 10−9 W·cm−1·Hz−1/2 was obtained for water vapor detection at atmospheric pressure. Huadan Zheng, Xukun Yin, Lei Dong, Hongpeng Wu, Xiaoli Liu, Weiguang Ma, Lei Zhang, Wangbao Yin, and Suotang Jia Copyright © 2015 Huadan Zheng et al. All rights reserved. Spectroscopic Analysis of Heterogeneous Biocatalysts for Biodiesel Production from Expired Sunflower Cooking Oil Thu, 17 Dec 2015 12:13:01 +0000 http://www.hindawi.com/journals/jspec/2015/714396/ The study characterized heterogeneous biocatalyst synthesized from sucrose, saw dust, and chicken egg shells using Fourier Transform Infrared (FTIR) spectroscopy coupled with Attenuated Total Reflectance (ATR) technique. Acidic sulphonate (–SO3H) groups were more visible in the spectrum generated for carbonized and sulphonated sucrose than in carbonized and sulphonated saw dust. This was highlighted further by the significantly higher conversion percentage achieved for sulphonated sucrose (62.5%) than sulphonated saw dust (46.6%) during esterification of expired sunflower oil (). The spectra for calcinated egg shells also showed that the most active form of calcium oxide was produced at calcination temperature of 1000°C. This was confirmed in the single-step transesterification reaction in which calcium oxide generated at 1000°C yielded the highest biodiesel (87.8%) from expired sunflower oil. The study further demonstrated the versatility of the FTIR technique in qualitative analysis of biodiesel and regular diesel by confirming the presence of specific characteristic peaks of diagnostic importance. These findings therefore highlight the potential of FTIR-ATR as an inexpensive, fast, and accurate diagnostic means for easy identification and characterization of different materials and products. Enoch Wembabazi, Patrick Joram Mugisha, Asumani Ratibu, Deborah Wendiro, Joseph Kyambadde, and Peter California Vuzi Copyright © 2015 Enoch Wembabazi et al. All rights reserved. A Biomedical Surface Enhanced Raman Scattering Substrate: Functionalized Three-Dimensional Porous Membrane Decorated with Silver Nanoparticles Wed, 16 Dec 2015 11:24:03 +0000 http://www.hindawi.com/journals/jspec/2015/561919/ We fabricated a simple, cheap, and functional surface enhanced Raman scattering substrate for biomedical application. Hot spots between two close silver nanoparticles distributed in the skeleton of a three-dimensional porous membrane, especially in the pores, were formed. The dual poles of micropores in the membrane were discussed. The pores could protect the silver nanoparticles in the pores from being oxidized, which makes the membrane effective for a longer period of time. In addition, Staphylococcus aureus cells could be trapped by the micropores and then the Raman signal became stronger, indicating that the functional surface enhanced Raman scattering substrate is reliable. Li Yuan, Jinghuai Fang, Yonglong Jin, Chaonan Wang, and Tian Xu Copyright © 2015 Li Yuan et al. All rights reserved. Opuntia ficus-indica Extract as Green Corrosion Inhibitor for Carbon Steel in 1 M HCl Solution Mon, 14 Dec 2015 07:11:00 +0000 http://www.hindawi.com/journals/jspec/2015/714692/ The effect of Opuntia ficus-indica (Nopal) as green corrosion inhibitor for carbon steel in 1 M HCl solution has been investigated by using weight loss tests, potentiodynamic polarization curves, and electrochemical impedance spectroscopy measurements. Also, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) analysis were performed. The inhibitor concentrations used ranged from 0 to 300 ppm at 25, 40, and 60°C. Results indicated the inhibition efficiency increases with increasing extract concentration and decreases with the temperature, and the inhibitor acted as a cathodic-type inhibitor which is physically absorbed onto the steel surface. In fact, the adsorption of the inhibitor on the steel surface follows the Langmuir adsorption isotherm, indicating monolayer adsorption. The presence of heteroatoms such as C, N, and O and OH groups were responsible for the corrosion inhibition. J. P. Flores-De los Ríos, M. Sánchez-Carrillo, C. G. Nava-Dino, J. G. Chacón-Nava, J. G. González-Rodríguez, E. Huape-Padilla, M. A. Neri-Flores, and A. Martínez-Villafañe Copyright © 2015 J. P. Flores-De los Ríos et al. All rights reserved. High-Speed Target Identification System Based on the Plume’s Spectral Distribution Mon, 30 Nov 2015 11:54:36 +0000 http://www.hindawi.com/journals/jspec/2015/937403/ In order to recognize the target of high speed quickly and accurately, an identification system was designed based on analysis of the distribution characteristics of the plume spectrum. In the system, the target was aligned with visible light tracking module, and the spectral analysis of the target’s plume radiation was achieved by interference module. The distinguishing factor recognition algorithm was designed on basis of ratio of multifeature band peaks and valley mean values. Effective recognition of the high speed moving target could be achieved after partition of the active region and the influence of target motion on spectral acquisition was analyzed. In the experiment the small rocket combustion was used as the target. The spectral detection experiment was conducted at different speeds 2.0 km away from the detection system. Experimental results showed that spectral distribution had significant spectral offset in the same sampling period for the target with different speeds, but the spectral distribution was basically consistent. Through calculation of the inclusion relationship between distinguishing factor and distinction interval of the peak value and the valley value at the corresponding wave-bands, effective identification of target could be achieved. Wenjie Lang, Guoguang Chen, Xiaoli Tian, and Changfan Xin Copyright © 2015 Wenjie Lang et al. All rights reserved. Influence of the Chemical Composition in the Electrochemical Response of Permanent Magnets Sun, 29 Nov 2015 12:06:12 +0000 http://www.hindawi.com/journals/jspec/2015/356027/ 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 http://www.hindawi.com/journals/jspec/2015/730753/ 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 http://www.hindawi.com/journals/jspec/2015/502340/ 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 http://www.hindawi.com/journals/jspec/2015/879062/ 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 http://www.hindawi.com/journals/jspec/2015/586514/ 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 http://www.hindawi.com/journals/jspec/2015/403160/ 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 http://www.hindawi.com/journals/jspec/2015/190157/ 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 http://www.hindawi.com/journals/jspec/2015/384214/ 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 http://www.hindawi.com/journals/jspec/2015/827160/ 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 http://www.hindawi.com/journals/jspec/2015/736382/ 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 http://www.hindawi.com/journals/jspec/2015/748673/ 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 http://www.hindawi.com/journals/jspec/2015/640271/ 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.