http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2013 , Hindawi Publishing Corporation . All rights reserved. Sun, 28 Apr 2013 08:36:15 +0000 http://www.hindawi.com/journals/ijs/2013/690186/ Anthropogenic emissions of carbon dioxide (CO2) have been identified as a major contributor to climate change. An attractive approach to tackle the increasing levels of CO2 in the atmosphere is direct extraction via absorption of CO2 from ambient air, to be subsequently desorbed and processed under controlled conditions. The feasibility of this approach depends on the sorbent material that should combine a long lifetime with nontoxicity, high selectivity for CO2, and favorable thermodynamic cycling properties. Adsorbents based on pore-expanded mesoporous silica grafted with amines have previously been found to combine high CO2 adsorption capacity at low partial pressures with operational stability under highly defined laboratory conditions. Here we examine the real potential and functionality of these materials by using more realistic conditions using both pure CO2, synthetic air, and, most importantly, ambient air. Through a combination of thermogravimetric analysis and Fourier transform infrared (TGA-FTIR) spectroscopy we address the primary functionality and by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy the observed degradation of the material on a molecular level. Annemarie Wagner, Bengt Steen, Göran Johansson, Ezio Zanghellini, Per Jacobsson, and Patrik Johansson Copyright © 2013 Annemarie Wagner et al. All rights reserved. Mon, 15 Apr 2013 14:50:19 +0000 http://www.hindawi.com/journals/ijs/2013/720598/ The possibilities of applications of vibrational spectroscopy techniques (Raman spectroscopy) in the analysis and characterization of polymers are more and more used and accurate. In this paper, our purpose is to characterize Low Density Poly(Ethylene) (LDPE) grades by Raman spectroscopy and in particular with CH2 Raman vibration modes. With temperature measurements, we determine different amorphous and crystalline Raman assignments. From these results and on the basis of the evolution of CH2 bending Raman vibration modes, we develop a phenomenological model in correlation with Differential Scanning Calorimetry and in particular with crystalline lamella thickness determination. Richard Jumeau, Patrice Bourson, Michel Ferriol, François Lahure, Marc Ponçot, and Abdesselam Dahoun Copyright © 2013 Richard Jumeau et al. All rights reserved. Sun, 24 Mar 2013 13:12:55 +0000 http://www.hindawi.com/journals/ijs/2013/341402/ This paper is a review of optical methods for online nondestructive food quality monitoring. The key spectral areas are the visual and near-infrared wavelengths. We have collected the information of over 260 papers published mainly during the last 20 years. Many of them use an analysis method called chemometrics which is shortly described in the paper. The main goal of this paper is to provide a general view of work done according to different FAO food classes. Hopefully using optical VIS/NIR spectroscopy gives an idea of how to better meet market and consumer needs for high-quality food stuff. Jarmo T. Alander, Vladimir Bochko, Birgitta Martinkauppi, Sirinnapa Saranwong, and Timo Mantere Copyright © 2013 Jarmo T. Alander et al. All rights reserved. Wed, 19 Dec 2012 11:55:38 +0000 http://www.hindawi.com/journals/ijs/2012/350684/ Surface-enhanced Raman scattering (SERS) was discovered in 1974 and impacted Raman spectroscopy and surface science. Although SERS has not been developed to be an applicable detection tool so far, nanotechnology has promoted its development in recent decades. The traditional SERS substrates, such as silver electrode, metal island film, and silver colloid, cannot be applied because of their enhancement factor or stability, but newly developed substrates, such as electrochemical deposition surface, Ag porous film, and surface-confined colloids, have better sensitivity and stability. Surface enhanced Raman scattering is applied in other fields such as detection of chemical pollutant, biomolecules, DNA, bacteria, and so forth. In this paper, the development of nanofabrication and application of surface-enhanced Ramans scattering substrate are discussed. Xian Zhang, Qin Zhou, Yu Huang, Zhengcao Li, and Zhengjun Zhang Copyright © 2012 Xian Zhang et al. All rights reserved. Mon, 26 Nov 2012 13:37:09 +0000 http://www.hindawi.com/journals/ijs/2012/710803/ This paper develops a novel embedded relay lens microscopic hyperspectral imaging system (ERL-MHSI) with high spectral resolution (nominal spectral resolution of 2.8 nm) and spatial resolution (30 μm × 10 μm) for cancer diagnosis. The ERL-MHSI system has transmittance and fluorescence mode. The transmittance can provide the morphological information for pathological diagnosis, and the fluorescence of cells or tissue can provide the characteristic signature for identification of normal and abnormal. In this work, the development of the ERL-MHSI system is discussed and the capability of the system is demonstrated by diagnosing early stage oral cancer of twenty mice in vitro. The best sensitivity for identifying normal cells and squamous cell carcinoma (SCC) was 100%. The best specificity for identifying normal cells and SCC was 99%. The best sensitivity for identifying normal cells and dysplasia was 99%. The best specificity for identifying normal cells and dysplasia was 97%. This work also utilizes fractal dimension to analyze the morphological information and find the significant different values between normal and SCC. Yao-Fang Hsieh, Mang Ou-Yang, Jeng-Ren Duann, Jin-Chern Chiou, Nai-Wen Chang, Chia-Ing Jan, Ming-Hsui Tsai, Shuen-De Wu, Yung-Jiun Lin, and Cheng-Chung Lee Copyright © 2012 Yao-Fang Hsieh et al. All rights reserved. Wed, 17 Oct 2012 15:35:37 +0000 http://www.hindawi.com/journals/ijs/2012/716527/ We report on a novel and extremely low-cost surface-enhanced Raman spectroscopy (SERS) substrate fabricated depositing gold nanoparticles on common lab filter paper using thermal inkjet technology. The paper-based substrate combines all advantages of other plasmonic structures fabricated by more elaborate techniques with the dynamic flexibility given by the inherent nature of the paper for an efficient sample collection, robustness, and stability. We describe the fabrication, characterization, and SERS activity of our substrate using 2,4,6-trinitrotoluene, 2,4-dinitrotoluene, and 1,3,5-trinitrobenzene as analytes. The paper-based SERS substrates presented a high sensitivity and excellent reproducibility for analytes employed, demonstrating a direct application in forensic science and homeland security. Pedro M. Fierro-Mercado and Samuel P. Hernández-Rivera Copyright © 2012 Pedro M. Fierro-Mercado and Samuel P. Hernández-Rivera. All rights reserved. Wed, 03 Oct 2012 15:45:59 +0000 http://www.hindawi.com/journals/ijs/2012/851923/ We have calculated the vibrational solvent shifts of the fundamental bands of HCl diluted in Ar, Kr, and Xe solutions at different thermodynamic conditions by means of the molecular dynamics technique and a model for the isotropic part of the interaction depending on the vibration. The theoretical vibrational shifts, which were compared with the available experimental data, have been determined by considering both, the usual linear Buckingham terms and the nonlinear anharmonic corrections, and the latter omitted in a previous work for the HCl in Ar and Kr. We have found that the Buckingham contributions dominate the solvent shifts of the fundamental bands of HCl in Ar, Kr, and Xe, although the anharmonic shifts’ present significant greater values than those obtained previously for N2 diluted in liquid Ar and pure liquid N2, both at normal conditions. We have analyzed the solvent shifts influence of the linear and quadratic (in the vibrational coordinate) oscillator-bath interaction terms and also the Dunham intramolecular potential effects on the anharmonic contributions. A. Padilla and J. Pérez Copyright © 2012 A. Padilla and J. Pérez. All rights reserved. Tue, 02 Oct 2012 10:53:55 +0000 http://www.hindawi.com/journals/ijs/2012/176851/ The need for portable technologies that can rapidly identify biological warfare agents (BWAs) in the field remains an international priority as expressed at the 2011 Biological Weapons Convention. In recent years, the ability of surface-enhanced Raman spectroscopy (SERS) to rapidly detect various BWAs at very low concentrations has been demonstrated. However, in the specific case of Bacillus anthracis, differentiation at the species level is required since other bacilli are common in the environment, representing potential false-positive responses. To overcome this limitation, we describe the use of a peptide attached to the SERS-active metal that selectively binds Bacillus anthracis-Sterne as the target analyte. Using this approach, 109  B. anthracis-Sterne spores/mL produced an intense dipicolinic acid spectrum upon the addition of acetic acid, while the same concentration and treatment of B. cereus and B. subtilis did not. Atanu Sengupta, Chetan Shende, Stuart Farquharson, and Frank Inscore Copyright © 2012 Atanu Sengupta et al. All rights reserved. Thu, 13 Sep 2012 15:13:19 +0000 http://www.hindawi.com/journals/ijs/2012/938407/ Raman spectroscopy has been shown to be a viable method for explosives detection. Currently most forensic Raman systems are either large, powerful instruments for laboratory experiments or handheld instruments for in situ point detection. We have chosen to examine the performance of certain benchtop Raman probe systems with the goal of developing an inexpensive, portable system that could be used to operate in a field forensics laboratory to examine explosives-related residues or samples. To this end, a rugged, low distortion line imaging dispersive Raman spectrograph was configured to work at 830 nm laser excitation and was used to determine whether the composition of thin films of plastic explosives or small (e.g., ≤10 μm) particles of RDX or other explosives or oxidizers can be detected, identified, and quantified in the field. With 300 mW excitation energy, concentrations of RDX and PETN can be detected and reconstructed in the case of thin Semtex smears, but further work is needed to push detection limits of areal dosages to the ~1 μg/cm2 level. We describe the performance of several probe/spectrograph combinations and show preliminary data for particle detection, calibration and detection linearity for mixed compounds, and so forth. James F. Kelly, Thomas A. Blake, Bruce E. Bernacki, and Timothy J. Johnson Copyright © 2012 James F. Kelly et al. All rights reserved. Mon, 10 Sep 2012 16:06:11 +0000 http://www.hindawi.com/journals/ijs/2012/124672/ The application of various microscopy methods such as luminescence microscopy, microspectrofluorimetry and laser-scanning confocal microscopy has been considered as an approach to study the autofluorescence of plant living cells—from cell diagnostics up to modelling the cell-cell contacts and cell interactions with fluorescent biologically active substances. It bases on the direct observations of secretions released from allelopathic and medicinal species and the cell-donor interactions with cell-acceptors as biosensors (unicellular plant generative and vegetative microspores). Special attention was paid to the interactions with pigmented and fluorescing components of the secretions released by the cells-donors from plant species. Colored components of secretions are considered as histochemical dyes for the analysis of cellular mechanisms at the cell-cell contacts and modelling of cell-cell interactions. The fluorescence of plant biosensors was also recommended for the testing of natural plant excretions as medical drugs. Victoria V. Roshchina Copyright © 2012 Victoria V. Roshchina. All rights reserved. Wed, 05 Sep 2012 15:13:35 +0000 http://www.hindawi.com/journals/ijs/2012/953019/ The vibrational spectrum of solid standard HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) was investigated. Two spectroscopic techniques were adopted for their different sensitivity and resolution. A preliminary survey of the absorption bands of the compound was performed in the 8000–400 cm−1 spectral range by employing the diffuse reflectance infrared Fourier transform (DRIFT) technique at room temperature. The high-resolution line spectrum of HMX was obtained in the 9.2–10.8 μm spectral range by laser photoacoustic spectroscopy (LPAS) method, using a line tuneable 10 W stabilised cw CO2 laser light source. By comparing the data collected with the two techniques in the common frequency range, a very good agreement was observed. A. Puiu, G. Giubileo, and S. Nunziante Cesaro Copyright © 2012 A. Puiu et al. All rights reserved. Tue, 28 Aug 2012 13:56:10 +0000 http://www.hindawi.com/journals/ijs/2012/474639/ The integrated band intensities of ethylene (12C2H4) in the 640–3260 cm−1 region were determined by Fourier transform infrared (FTIR) spectroscopy. The infrared absorbance spectra of the 𝜈7 and 𝜈10, 𝜈12, 𝜈7+𝜈8, 𝜈6+𝜈10, 𝑣11, and 𝜈9 and 𝜈2+𝜈12 bands of ethylene recorded at a resolution of 0.5 cm−1 were measured at an ambient temperature of 296 K at various vapor pressures ranging from 3×10−5 to 1×10−3 atm to obtain respective Beer-Lambert's law plots. The measured integrated band intensities in cm−1/cm atm were 𝑆(𝜈9and𝜈2+𝜈12)=112.20±0.24, 𝑆(𝜈11)=55.35±0.14, 𝑆(𝜈12)=41.22±0.30, and 𝑆(𝜈7and𝜈10)=328.66±16.55. In addition, the measured infrared band intensities of the 𝜈7+𝜈8 and 𝜈6+𝜈10 combination bands of ethylene are reported for the first time: 𝑆(𝜈7+𝜈8)=21.701±0.028 cm−1/cm atm and 𝑆(𝜈6+𝜈10)=2.568±0.025 cm−1/cm atm. G. B. Lebron and T. L. Tan Copyright © 2012 G. B. Lebron and T. L. Tan. All rights reserved. Sun, 15 Jul 2012 13:06:18 +0000 http://www.hindawi.com/journals/ijs/2012/284173/ The mechanism of the interaction between bovine serum albumin (BSA) and ceftriaxone with and without zinc (II) (Zn2+) was studied employing fluorescence, ultraviolet (UV) absorption, circular dichroism (CD), and synchronous fluorescence spectral methods. The intrinsic fluorescence of BSA was quenched by ceftriaxone in a static quenching mode, which was authenticated by Stern-Volmer calculations. The binding constant, the number of binding sites, and the thermodynamic parameters were obtained, which indicated a spontaneous and hydrophobic interaction between BSA and ceftriaxone regardless of Zn2+. Changes in UV absorption, CD, and synchronous fluorescence spectral data are due to the microenvironment of amide moieties in BSA molecules. In the BSA-ceftriaxone-Zn2+ system, Zn2+ must first interact with ceftriaxone forming a complex, which inhibits BSA binding to ceftriaxone. The present work uses spectroscopy to elucidate the mechanism behind the interaction between BSA and ceftriaxone in the presence and absence of Zn2+. The BSA and ceftriaxone complex provides a model for studying drug-protein interactions and thus may further facilitate the study of drug metabolism and transportation. Qiaoli Yue, Tongfei Shen, Changna Wang, Chaohui Gao, and Jifeng Liu Copyright © 2012 Qiaoli Yue et al. All rights reserved. Thu, 05 Jul 2012 14:05:03 +0000 http://www.hindawi.com/journals/ijs/2012/297056/ As Raman spectroscopy continues to evolve, questions arise as to the portability of Raman data: dispersive versus Fourier transform, wavelength calibration, intensity calibration, and in particular the frequency of the excitation laser. While concerns about fluorescence arise in the visible or ultraviolet, most modern (portable) systems use near-infrared excitation lasers, and many of these are relatively close in wavelength. We have investigated the possibility of porting reference data sets from one NIR wavelength system to another: We have constructed a reference library consisting of 145 spectra, including 20 explosives, as well as sundry other compounds and materials using a 1064 nm spectrometer. These data were used as a reference library to evaluate the same 145 compounds whose experimental spectra were recorded using a second 785 nm spectrometer. In 128 cases of 145 (or 88.3% including 20/20 for the explosives), the compounds were correctly identified with a mean “hit score” of 954 of 1000. Adding in criteria for when to declare a correct match versus when to declare uncertainty, the approach was able to correctly categorize 134 out of 145 spectra, giving a 92.4% accuracy. For the few that were incorrectly identified, either the matched spectra were spectroscopically similar to the target or the 785 nm signal was degraded due to fluorescence. The results indicate that imported data recorded at a different NIR wavelength can be successfully used as reference libraries, but key issues must be addressed: the reference data must be of equal or higher resolution than the resolution of the current sensor, the systems require rigorous wavelength calibration, and wavelength-dependent intensity response should be accounted for in the different systems. Timothy J. Johnson, Yin-Fong Su, Kristin H. Jarman, Brenda M. Kunkel, Jerome C. Birnbaum, Alan G. Joly, Eric G. Stephan, Russell G. Tonkyn, Robert G. Ewing, and Glen C. Dunham Copyright © 2012 Timothy J. Johnson et al. All rights reserved. Wed, 06 Jun 2012 08:11:51 +0000 http://www.hindawi.com/journals/ijs/2012/808079/ Raman spectroscopy is an analytical technique with vast applications in the homeland security and defense arenas. The Raman effect is defined by the inelastic interaction of the incident laser with the analyte molecule’s vibrational modes, which can be exploited to detect and identify chemicals in various environments and for the detection of hazards in the field, at checkpoints, or in a forensic laboratory with no contact with the substance. A major source of error that overwhelms the Raman signal is fluorescence caused by the background and the sample matrix. Novel methods are being developed to enhance the Raman signal’s sensitivity and to reduce the effects of fluorescence by altering how the hazard material interacts with its environment and the incident laser. Basic Raman techniques applicable to homeland security applications include conventional (off-resonance) Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS), resonance Raman spectroscopy, and spatially or temporally offset Raman spectroscopy (SORS and TORS). Additional emerging Raman techniques, including remote Raman detection, Raman imaging, and Heterodyne imaging, are being developed to further enhance the Raman signal, mitigate fluorescence effects, and monitor hazards at a distance for use in homeland security and defense applications. Gregory Mogilevsky, Laura Borland, Mark Brickhouse, and Augustus W. Fountain III Copyright © 2012 Gregory Mogilevsky et al. All rights reserved. Tue, 15 May 2012 10:54:45 +0000 http://www.hindawi.com/journals/ijs/2012/174697/ A novel approach of rare earth elements (REE) determination in crude oil is suggested. Special application of countercurrent chromatography (CCC) is used as a sample pretreatment tool. An oil sample is continuously pumped through the rotating coil column (RCC) as a mobile phase, while an aqueous phase (nitric acid solution) is retained as a stationary phase. Two phases are kept well mixed and agitated, but there is no emulsion at the interface under the chosen conditions. Special features of CCC give an opportunity to vary the volume of oil samples to be analyzed from 10 mL to 1 L or more. Trace metals are preconcentrated into 10 mL of stationary phase (acidic solutions) pumped out of the column so that analysis can be easily determined with inductively coupled plasma mass spectrometry (ICP-MS) without additional sample preparation procedures. Optimal concentration of nitric acid in the stationary phase for preconcentration of REE from oil by CCC has been investigated. The combination of CCC with ICP-MS gives the possibility to develop a rapid, reliable, and accurate method of trace metal including rare earth elements (REE) determination in crude oils and oil products. Such method could be an alternative for unexpanded and expensive neutron-activation analysis (NAA). Alexander Soin, Tatiana Maryutina, Natalya Musina, and Andrey Soin Copyright © 2012 Alexander Soin et al. All rights reserved. Tue, 15 May 2012 08:17:17 +0000 http://www.hindawi.com/journals/ijs/2012/472031/ Recent studies on the mammalian and fungal metabolism of the mycotoxin zearalenone (ZEN) have disclosed the formation of six regioisomers of monohydroxy-ZEN and its reductive metabolite zearalenol (ZEL). Hydroxylation occurs at the aromatic ring or at one of four positions of the aliphatic macrocycle. In addition, an aliphatic ZEN epoxide, its hydrolysis product, and other products were identified in fungal cultures. In this paper, we report the product ion spectra of the [M-H]− ions of 22 oxidative metabolites of ZEN and ZEL, obtained by LC-MS2 analysis using a linear ion trap mass spectrometer with negative electrospray ionization. The MS2 spectra exhibit qualitative and quantitative differences which allow a clear distinction of most metabolites. Moreover, GC-MS analysis of the trimethylsilylated metabolites yields electron impact mass spectra with numerous fragment ions which can be used as fingerprint to confirm the chemical structure derived by LC-MS2 analysis. Andreas A. Hildebrand, Erika Pfeiffer, Georg Damm, and Manfred Metzler Copyright © 2012 Andreas A. Hildebrand et al. All rights reserved. Tue, 24 Apr 2012 10:59:54 +0000 http://www.hindawi.com/journals/ijs/2012/462901/ Interaction and surface binding characteristics of staphylococcal protein A (SpA) and an anti-Escherichia coli immunoglobulin G (IgG) were studied using the Raman spectroscopy. The tyrosine amino acid residues present in the α-helix structure of SpA were found to be involved in interaction with IgG. In bulk interaction condition the native structure of proteins was almost preserved where interaction-related changes were observed in the overall secondary structure (α-helix) of SpA. In the adsorbed state, the protein structure was largely modified, which allowed the identification of tyrosine amino acids involved in SpA and IgG interaction. This study constitutes a direct Raman spectroscopic investigation of SpA and IgG (receptor-antibody) interaction mechanism in the goal of a future biosensor application for detection of pathogenic microorganisms. R. P. Kengne-Momo, Ph. Daniel, F. Lagarde, Y. L. Jeyachandran, J. F. Pilard, M. J. Durand-Thouand, and G. Thouand Copyright © 2012 R. P. Kengne-Momo et al. All rights reserved. Sun, 22 Apr 2012 16:08:45 +0000 http://www.hindawi.com/journals/ijs/2012/959235/ Raman microimaging is a potential analytical technique in health field and presents many possible pharmaceutical applications. In this study, we tested a micrometer spatial resolution probe coupled to a portable Raman imager via an indexed multifiber bundle. At the level of the probe, the fibers were arranged in a circular geometry in order to fit to the pupil of an objective. The imaging potential of this Raman system was assessed on pharmaceutical-like pellets. We showed that this setup permits to record, nearly in real time, Raman images with a micrometer resolution. The collected images revealed a marked heterogeneity in chemicals distribution. Further investigations will be led on cells and biological tissues to evaluate the potential of this Raman imaging device for biomedical applications. Sana Tfaili, Cyril Gobinet, Jean-François Angiboust, Michel Manfait, and Olivier Piot Copyright © 2012 Sana Tfaili et al. All rights reserved. Thu, 12 Apr 2012 14:31:52 +0000 http://www.hindawi.com/journals/ijs/2012/894891/ The mass spectra of a series of stevioside analogues including the amide and dimer compounds of steviol, isosteviol, and steviolbioside were examined. Positive ion mass spectral fragmentation of new steviol, isosteviol, and steviolbioside amides and the amide dimers are reported and discussed. The techniques included their synthesis procedures, fast-atom bombardment (FAB), and LC/MS/MS mass spectra. Intense [M+H]+ and [M+Na]+ ion peaks were observed on the FAB and ESI spectra. LC/MS/MS also yielded ES+ and ES− ion peaks that fairly agreed with the results of the FAB and ESI studies. Mass spectral analysis of compounds 4p-q, 5a-g, 6, and 7 revealed the different cleavage pathway patterns that can help in identifying the structures of steviolbioside and its amide derivatives. Lin-Wen Lee, Tzong-Huei Lee, Ching-Tung Lin, Tiffany Chen, and Pen-Yuan Lin Copyright © 2012 Lin-Wen Lee et al. All rights reserved. Sun, 08 Apr 2012 12:12:57 +0000 http://www.hindawi.com/journals/ijs/2012/983523/ Intramolecular mobility of positive charge carriers in conjugated polymer films based on dithieno [2,3-b: 2,3-d] pyrrole (DTP) is studied by time-resolved microwave conductivity (TRMC). A series of DTP homopolymer and copolymers combined with phenyl, 2,2-biphenyl, thiophene, 2,2-bithiophene, and 9,9-dioctylfluorene were synthesized by Suzuki-Miyaura and Yamamoto coupling reactions. Polymers containing DTP unit are reported to show high value of hole mobility measured by FET method, and this type of polymers is expected to have stable HOMO orbitals which are important for hole transportation. Among these copolymers, DTP coupled with 9,9-dioctylfluorene copolymer showed the highest charge carrier mobility as high as 1.7 cm2/Vs, demonstrating an excellent electrical property on rigid copolymer backbones. Yoshihito Honsho, Akinori Saeki, and Shu Seki Copyright © 2012 Yoshihito Honsho et al. All rights reserved. Tue, 28 Feb 2012 12:59:32 +0000 http://www.hindawi.com/journals/ijs/2012/323859/ Vaginal infections (vaginosis) globally affect more than 15% of the female population of reproductive age. However, diagnosis of vaginosis and differentiating between the three common types: bacterial vaginosis (BV), vulvovaginal candidiasis (VVC), and trichomoniasis are challenging. Elevated levels of the biogenic amines, trimethylamine (TMA), putrescine, and cadaverine have been found in vaginal discharge fluid of women with vaginosis. Ion mobility spectrometry (IMS) is particularly suitable for measurement of amines even in complex biological matrices due to their high proton affinity and has been shown to be suitable for the diagnosis of vaginal infections. Recent developments that have increased the accuracy of the technique for diagnosis of BV and simplified sample introduction are described here. Zeev Karpas, Gabi Cohen, Elias Atweh, Geoff Barnard, and Moshe Golan Copyright © 2012 Zeev Karpas et al. All rights reserved. Sun, 26 Feb 2012 14:55:17 +0000 http://www.hindawi.com/journals/ijs/2012/463731/ Raman spectroscopy has been widely proposed as a technique to nondestructively and noninvasively interrogate the contents of glass and plastic bottles. In this work, Raman spectroscopy is used in a concealed threat scenario where hazardous liquids have been intentionally mixed with common consumer products to mask its appearance or spectra. The hazardous liquids under consideration included the chemical warfare agent (CWA) simulant triethyl phosphate (TEP), hydrogen peroxide, and acetone as representative of toxic industrial compounds (TICs). Fiber optic coupled Raman spectroscopy (FOCRS) and partial least squares (PLS) algorithm analysis were used to quantify hydrogen peroxide in whiskey, acetone in perfume, and TEP in colored beverages. Spectral data was used to evaluate if the hazardous liquids can be successfully concealed in consumer products. Results demonstrated that FOC-RS systems were able to discriminate between nonhazardous consumer products and mixtures with hazardous materials at concentrations lower than 5%. Michael L. Ramírez-Cedeño, Natalie Gaensbauer, Hilsamar Félix-Rivera, William Ortiz-Rivera, Leonardo Pacheco-Londoño, and Samuel P. Hernández-Rivera Copyright © 2012 Michael L. Ramírez-Cedeño et al. All rights reserved. Wed, 22 Feb 2012 10:52:30 +0000 http://www.hindawi.com/journals/ijs/2012/158715/ Resonance-enhanced Raman spectroscopy has been used to perform standoff measurements on nitromethane (NM), 2,4-DNT, and 2,4,6-TNT in vapor phase. The Raman cross sections for NM, DNT, and TNT in vapor phase have been measured in the wavelength range 210–300 nm under laboratory conditions, in order to estimate how large resonance enhancement factors can be achieved for these explosives. The results show that the signal is enhanced up to 250,000 times for 2,4-DNT and up to 60,000 times for 2,4,6-TNT compared to the nonresonant signal at 532 nm. Realistic outdoor measurements on NM in vapor phase at 13 m distance were also performed, which indicate a potential for resonance Raman spectroscopy as a standoff technique for detection of vapor phase explosives. In addition, the Raman spectra of acetone, ethanol, and methanol were measured at the same wavelengths, and their influence on the spectrum from NM was investigated. Anneli Ehlerding, Ida Johansson, Sara Wallin, and Henric Östmark Copyright © 2012 Anneli Ehlerding et al. All rights reserved. Tue, 21 Feb 2012 11:06:10 +0000 http://www.hindawi.com/journals/ijs/2012/432046/ The calorimetric and infrared (IR) spectroscopy measurements of polyethylene oxide (PEO) are used to evaluate the deformation and relaxation that films experience during a temperature cycle (30°C–90°C–30°C). After melting, the intensity of some bands decreases by 10 to 70%. During the temperature cycle, the C–O band in the 1100 cm−1 region and the C–C–O deformation bands at 650 and 500 cm−1 show some new features. A network of cooperative oxygen-hydrogen interactions between the PEO chains form in films with special history, namely, in thermally treated films, in thin films prepared from gel forming solutions, and in thick films after aging. The interchain interaction network is suggested from the IR absorption bands in the 1200 and 900 cm−1 region and also from small bands at 1144 and 956 cm−1. The network seems absent or reduced in thin films. IR spectroscopy appears a sensitive technique to study chain conformations in PEO films and in other materials where order, disorder, and the formation of intermolecular interactions coexist. Carl Bergeron, Etienne Perrier, Aymeric Potier, and Geneviève Delmas Copyright © 2012 Carl Bergeron et al. All rights reserved. Mon, 20 Feb 2012 11:25:56 +0000 http://www.hindawi.com/journals/ijs/2012/501706/ We report the application of confocal laser scanning microscopy CLSM and Raman spectroscopy on the (bio)chemical oxidation of pyrite and chalcopyrite, in order to understand how surface sulfur species (S𝑛2−/S0) affects biofilm evolution during mineral colonization by Acidithiobacillus thiooxidans. We found that cells attachment occurs as cells clusters and monolayered biofilms within the first 12 h. Longer times resulted in the formation of micro- and macrocolonies with variable cell density and higher epifluorescence signal of the extracellular polymeric substances (EPS), indicating double dynamic activity of A. thiooxidans: sulfur biooxidation and biofilm formation. Raman spectra indicated S𝑛2−/S0 consumption modification during biofilm evolution. Hence, cell density increase was primarily associated with the presence of S0; the presence of refractory sulfur species on the mineral surfaces does not to affect biofilm evolution. The EPS of the biofilms was mainly composed of extracellular hydrophobic compounds (vr. gr. lipids) and a minor content of hydrophilic exopolysaccharides, suggesting a hydrophobic interaction between attached cells and the altered pyrite and chalcopyrite. J. V. García-Meza, R. H. Lara, and H. R. Navarro-Contreras Copyright © 2012 J. V. García-Meza et al. All rights reserved. Wed, 15 Feb 2012 10:57:13 +0000 http://www.hindawi.com/journals/ijs/2012/234949/ We present results from mass spectrometric analysis of NIST standard materials and meteoritic samples conducted by a miniaturised laser ablation mass spectrometer designed for space research. The mass analyser supports investigation with a mass resolution (𝑚/Δ𝑚) ≈ 500–600 and dynamic range within seven decades. Nevertheless, to maintain an optimal spectral quality laser irradiances lower than ~1 GW/cm2 are applied so far which results in a spread of RSC values. To achieve the quantitative performance of mass analyser, various effects influencing RSC factors have to be investigated. In this paper we investigate influence of laser irradiance, sampling procedure and plasma chemistry on the quantitative elemental and isotopic analysis. The studies indicate necessity for accurate control of laser characteristics and acquisition procedure. A relatively low irradiance applied causes a negligible sample damage and allows for accumulation of large number of waveforms from one sample location. The procedure yields statistically well averaged data and allows a sensitive in-depth analysis. The quantitative analyses of isotopic composition can be performed with accuracy and precision better as 1% and 2%, for isotopic patterns of elements and clusters, respectively. The numerical integration methods would be preferred to achieve more accurate results. The measurements of Allende sample yield detection of Pb isotopic pattern, nevertheless cluster species are readily observed in spectrum and make the elemental analysis of other trace elements difficult due to isobaric interferences. These detections are of a considerable interest because of possible application of the instrument for in situ elemental and isotopic analysis and radiometric dating of solids. Marek Tulej, Andreas Riedo, Maria Iakovleva, and Peter Wurz Copyright © 2012 Marek Tulej et al. All rights reserved. Wed, 08 Feb 2012 10:50:57 +0000 http://www.hindawi.com/journals/ijs/2012/197609/ We report the development of Raman spectroscopy as a powerful tool for quantitative analysis of point defect and defect clusters in irradiated graphite. Highly oriented pyrolytic graphite (HOPG) was irradiated by 25 keV He+ and 20 keV D+ ions. Raman spectroscopy and transmission electron microscopy revealed a transformation of irradiated graphite into amorphous state. Annealing experiment indicated a close relation between Raman intensity ratio and vacancy concentration. The change of Raman spectra under irradiation was empirically analyzed by “disordered-region model,” which assumes the transformation from vacancy-contained region to disordered region. The model well explains the change of Raman spectra and predicts the critical dose of amorphization, but the nature of the disordered region is unclear. Then, we advanced the model into “dislocation accumulation model,” assigning the disordered region to dislocation dipole. Dislocation accumulation model can simulate the irradiation time dependencies of Raman intensity ratio and the c-axis expansion under irradiation, giving a relation between the absolute concentration of vacancy and Raman intensity ratio, suggesting an existence of the barrier on the mutual annihilation of vacancy and interstitial. Keisuke Niwase Copyright © 2012 Keisuke Niwase. All rights reserved. Sun, 22 Jan 2012 15:38:57 +0000 http://www.hindawi.com/journals/ijs/2012/494301/ Portable unilateral NMR was used to quantitatively map in a fully noninvasive way the moisture distribution in an ancient deteriorated wall painting before and after an intervention to reduce the capillary raise of water through the wall. Maps obtained at a depth of 0.5 cm clearly showed the path of the capillary raise and indicated that, after the intervention, the moisture level was reduced. Maps obtained by measuring the first layers of the wall painting were affected by the critical environmental conditions of the second hypogeous level of St. Clement Basilica, Rome, and by the presence of salts efflorescence and encrustations on the surface of the wall painting. The morphology and the elemental composition of salts investigated by SEM-EDS indicated that efflorescences and encrustations were mostly constituted of gypsum and calcite. The presence of these salts is explained with the presence of high concentration of carbon dioxide and sulphur-rich particles due to pollution which, along with the high-moisture level and the extremely feeble air circulation, cause recarbonation and sulphation processes on the plaster surface. Valeria Di Tullio, Noemi Proietti, Gennaro Gentile, Elisabetta Giani, Domenico Poggi, and Donatella Capitani Copyright © 2012 Valeria Di Tullio et al. All rights reserved. Wed, 18 Jan 2012 10:27:37 +0000 http://www.hindawi.com/journals/ijs/2012/894841/ Laser-spectrometric methods to derive absolute and traceable carbon monoxide (CO) amount fractions in exhaled human breath could be of advantage for early disease detection as well as for treatment monitoring. As proof-of-principle laboratory experiment, we employed intra-pulse and continuous wave (cw) quantum cascade laser spectroscopy (QCLAS), both at 4.6 μm. Additional experiments were carried out applying cw cavity ring-down spectroscopy (CRDS) with a CO sideband laser and a QCL. We emphasize metrological data quality objectives, thatis, traceability and uncertainty, which could serve as essential benefits to exhaled breath measurements. The results were evaluated and compared on a 100 μmol/mol CO level using the two QCLAS spectrometers, and the cw CO sideband laser CRDS setup. The relative standard uncertainties of the pulsed and the cw QCLAS CO amount fraction results were ±4.8 and ±2.8%, respectively, that from the CO sideband laser CRDS was ±2.7%. Sensitivities down to a 3 nmol/mol CO level were finally demonstrated and quantified by means of cw CRDS equipped with a QCL yielding standard uncertainties of about ±2.5 that are exclusively limited by the available line strength figure quality. With this study we demonstrate the achieved comparability of CO quantifications, adhering metrological principles. Javis Anyangwe Nwaboh, Stefan Persijn, Kathrin Heinrich, Marcus Sowa, Peter Hering, and Olav Werhahn Copyright © 2012 Javis Anyangwe Nwaboh et al. All rights reserved.