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Sample records for reflectance infrared spectroscopy

  1. Forensic applications of microscopical infrared internal reflection spectroscopy

    Science.gov (United States)

    Tungol, Mary W.; Bartick, Edward G.; Reffner, John A.

    1994-01-01

    Applications of microscopical infrared internal reflection spectroscopy in forensic science are discussed. Internal reflection spectra of single fibers, hairs, paint chips, vehicle rubber bumpers, photocopy toners, carbon copies, writing ink on paper, lipstick on tissue, black electrical tape, and other types of forensic evidence have been obtained. The technique is convenient, non-destructive, and may permit smeared materials to be analyzed in situ.

  2. Mid infrared upconversion spectroscopy using diffuse reflectance

    DEFF Research Database (Denmark)

    Sanders, Nicolai Højer; Kehlet, Louis M.; Dam, Jeppe Seidelin

    2014-01-01

    specifically that upconversion methods can be deployed using a diffuse reflectance setup where the test sample is irradiated by a thermal light source, i.e. a globar. The diffuse reflectance geometry is particularly well suited when a transmission setup cannot be used. This situation may happen for highly...

  3. Prediction of tablets disintegration times using near-infrared diffuse reflectance spectroscopy as a nondestructive method.

    Science.gov (United States)

    Donoso, M; Ghaly, Evone S

    2005-01-01

    The goals of this study are to user near-infrared reflectance (NIR) spectroscopy to measure the disintegration time of a series of tablets compacted at different compressional forces, calibrate NIR data vs. laboratory equipment data, develop a model equation, validate the model, and test the model's predictive ability. Seven theophylline tablet formulations of the same composition but with different disintegration time values (0.224, 1.141, 2.797, 5.492, 9.397, 16.8, and 30.092 min) were prepared along with five placebo tablet formulations with different disintegration times. Laboratory disintegration time was compared to near-infrared diffuse reflectance data. Linear regression, quadratic, cubic, and partial least square techniques were used to determine the relationship between disintegration time and near-infrared spectra. The results demonstrated that an increase in disintegration time produced an increase in near-infrared absorbance. Series of model equations, which depended on the mathematical technique used for regression, were developed from the calibration of disintegration time using laboratory equipment vs. the near-infrared diffuse reflectance for each formulation. The results of NIR disintegration time were similar to laboratory tests. The near-infrared diffuse reflectance spectroscopy method is an alternative nondestructive method for measurement of disintegration time of tablets.

  4. [Application of Fourier transform attenuated total reflection infrared spectroscopy in analysis of pulp and paper industry].

    Science.gov (United States)

    Zhang, Yong; Cao, Chun-yu; Feng, Wen-ying; Xu, Ming; Su, Zhen-hua; Liu, Xiao-meng; Lü, Wei-jun

    2011-03-01

    As one of the most powerful tools to investigate the compositions of raw materials and the property of pulp and paper, infrared spectroscopy has played an important role in pulp and paper industry. However, the traditional transmission infrared spectroscopy has not met the requirements of the producing processes because of its disadvantages of time consuming and sample destruction. New technique would be needed to be found. Fourier transform attenuated total reflection infrared spectroscopy (ATR-FTIR) is an advanced spectroscopic tool for nondestructive evaluation and could rapidly, accurately estimate the production properties of each process in pulp and paper industry. The present review describes the application of ATR-FTIR in analysis of pulp and paper industry. The analysis processes will include: pulping, papermaking, environmental protecting, special processing and paper identifying.

  5. Analysis of bacteria on steel surfaces using reflectance micro-Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Ojeda, Jesús J; Romero-González, María E; Banwart, Steven A

    2009-08-01

    Reflectance micro-Fourier transform infrared (FT-IR) analysis has been applied to characterize biofilm formation of Aquabacterium commune, a common microorganism present on drinking water distribution systems, onto the increasingly popular pipe material stainless steel EN1.4307. The applicability of the reflectance micro-FT-IR technique for analyzing the bacterial functional groups is discussed, and the results are compared to spectra obtained using more conventional FT-IR techniques: transmission micro-FT-IR, attenuated transmitted reflectance (ATR), and KBr pellets. The differences between the infrared spectra of wet and dried bacteria, as well as free versus attached bacteria, are also discussed. The spectra obtained using reflectance micro-FT-IR spectroscopy were comparable to those obtained using other FT-IR techniques. The absence of sample preparation, the potential to analyze intact samples, and the ability to characterize opaque and thick samples without the need to transfer the bacterial samples to an infrared transparent medium or produce a pure culture were the main advantages of reflectance micro-FT-IR spectroscopy.

  6. Disposable attenuated total reflection-infrared crystals from silicon wafer: a versatile approach to surface infrared spectroscopy.

    Science.gov (United States)

    Karabudak, Engin; Kas, Recep; Ogieglo, Wojciech; Rafieian, Damon; Schlautmann, Stefan; Lammertink, R G H; Gardeniers, Han J G E; Mul, Guido

    2013-01-02

    Attenuated total reflection-infrared (ATR-IR) spectroscopy is increasingly used to characterize solids and liquids as well as (catalytic) chemical conversion. Here we demonstrate that a piece of silicon wafer cut by a dicing machine or cleaved manually can be used as disposable internal reflection element (IRE) without the need for polishing and laborious edge preparation. Technical aspects, fundamental differences, and pros and cons of these novel disposable IREs and commercial IREs are discussed. The use of a crystal (the Si wafer) in a disposable manner enables simultaneous preparation and analysis of substrates and application of ATR spectroscopy in high temperature processes that may lead to irreversible interaction between the crystal and the substrate. As representative application examples, the disposable IREs were used to study high temperature thermal decomposition and chemical changes of polyvinyl alcohol (PVA) in a titania (TiO(2)) matrix and assemblies of 65-450 nm thick polystyrene (PS) films.

  7. Quantification of SOC and Clay Content Using Visible Near-Infrared Reflectance–Mid-Infrared Reflectance Spectroscopy With Jack-Knifing Partial Least Squares Regression

    DEFF Research Database (Denmark)

    Peng, Yi; Knadel, Maria; Gislum, René

    2014-01-01

    A total of 125 soil samples were collected from a Danish field varying in soil texture from sandy to loamy. Visible near-infrared reflectance (Vis-NIR) and mid-infrared reflectance (MIR) spectroscopy combined with chemometric methods were used to predict soil organic carbon (SOC) and clay content...

  8. The Bone Black Pigment Identification by Noninvasive, In Situ Infrared Reflection Spectroscopy

    Directory of Open Access Journals (Sweden)

    Alessia Daveri

    2018-01-01

    Full Text Available Two real case studies, an oil painting on woven paper and a cycle of mural paintings, have been presented to validate the use of infrared reflection spectroscopy as suitable technique for the identification of bone black pigment. By the use of the sharp weak band at 2013 cm−1, it has been possible to distinguish animal carbon-based blacks by a noninvasive method. Finally, an attempt for an eventual assignment for the widely used sharp band at 2013 cm−1 is discussed.

  9. Determination of soil content in chlordecone (organochlorine pesticide) using near infrared reflectance spectroscopy (NIRS)

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, Didier, E-mail: didier.brunet@ird.f [IRD - Institut de Recherche pour le Developpement, UMR Eco and Sols (Ecologie Fonctionnelle et Biogeochimie des Sols), Montpellier SupAgro, Batiment 12, 2 place Viala, 34060 Montpellier Cedex 1 (France); Woignier, Thierry [IRD, UMR Eco and Sols, PRAM (Pole de Recherche Agronomique de la Martinique), BP 213, Petit Morne, 97232 Le Lamentin, Martinique (French West Indies) (France); CNRS - Centre National de la Recherche Scientifique, Universite Montpellier 2, place Eugene Bataillon, 34095 Montpellier Cedex 5 (France); Lesueur-Jannoyer, Magalie; Achard, Raphael [CIRAD (Centre de Cooperation Internationale en Recherche Agronomique pour le Developpement), PRAM, BP 213, Petit Morne, 97232 Le Lamentin, Martinique (French West Indies) (France); Rangon, Luc [IRD, UMR Eco and Sols, PRAM (Pole de Recherche Agronomique de la Martinique), BP 213, Petit Morne, 97232 Le Lamentin, Martinique (French West Indies) (France); Barthes, Bernard G. [IRD - Institut de Recherche pour le Developpement, UMR Eco and Sols (Ecologie Fonctionnelle et Biogeochimie des Sols), Montpellier SupAgro, Batiment 12, 2 place Viala, 34060 Montpellier Cedex 1 (France)

    2009-11-15

    Chlordecone is a toxic organochlorine insecticide that was used in banana plantations until 1993 in the French West Indies. This study aimed at assessing the potential of near infrared reflectance spectroscopy (NIRS) for determining chlordecone content in Andosols, Nitisols and Ferralsols from Martinique. Using partial least square regression, chlordecone content conventionally determined through gas chromatography-mass spectrometry could be correctly predicted by NIRS (Q{sup 2} = 0.75, R{sup 2} = 0.82 for the total set), especially for samples with chlordecone content <12 mg kg{sup -1} or when the sample set was rather homogeneous (Q{sup 2} = 0.91, R{sup 2} = 0.82 for the Andosols). Conventional measures and NIRS predictions were poorly correlated for chlordecone content >12 mg kg{sup -1}, nevertheless ca. 80% samples were correctly predicted when the set was divided into three or four classes of chlordecone content. Thus NIRS could be considered a time- and cost-effective method for characterising soil contamination by chlordecone. - Soil content in chlordecone, an organochlorine insecticide, can be determined time- and cost-effectively using near infrared reflectance spectroscopy (NIRS).

  10. Determination of soil content in chlordecone (organochlorine pesticide) using near infrared reflectance spectroscopy (NIRS)

    International Nuclear Information System (INIS)

    Brunet, Didier; Woignier, Thierry; Lesueur-Jannoyer, Magalie; Achard, Raphael; Rangon, Luc; Barthes, Bernard G.

    2009-01-01

    Chlordecone is a toxic organochlorine insecticide that was used in banana plantations until 1993 in the French West Indies. This study aimed at assessing the potential of near infrared reflectance spectroscopy (NIRS) for determining chlordecone content in Andosols, Nitisols and Ferralsols from Martinique. Using partial least square regression, chlordecone content conventionally determined through gas chromatography-mass spectrometry could be correctly predicted by NIRS (Q 2 = 0.75, R 2 = 0.82 for the total set), especially for samples with chlordecone content -1 or when the sample set was rather homogeneous (Q 2 = 0.91, R 2 = 0.82 for the Andosols). Conventional measures and NIRS predictions were poorly correlated for chlordecone content >12 mg kg -1 , nevertheless ca. 80% samples were correctly predicted when the set was divided into three or four classes of chlordecone content. Thus NIRS could be considered a time- and cost-effective method for characterising soil contamination by chlordecone. - Soil content in chlordecone, an organochlorine insecticide, can be determined time- and cost-effectively using near infrared reflectance spectroscopy (NIRS).

  11. CO Adsorption and Oxidation at the Catalyst-Water Interface: An Investigation by Attenuated Total Reflection Infrared Spectroscopy.

    NARCIS (Netherlands)

    Ebbesen, S.D.; Mojet, Barbara; Lefferts, Leonardus

    2006-01-01

    Adsorption of carbon monoxide and oxidation of preadsorbed carbon monoxide from gas and aqueous phases were studied on a platinum catalyst deposited on a ZnSe internal reflection element (IRE) using attenuated total reflection infrared (ATR-IR) spectroscopy. The results of this study convincingly

  12. Quantum state-resolved gas/surface reaction dynamics probed by reflection absorption infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chen Li [Department of Dynamics at Surfaces, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Goettingen (Germany); Ueta, Hirokazu; Beck, Rainer D. [Laboratoire de Chimie Physique Moleculaire, Ecole Polytechnique Federale de Lausanne (Switzerland); Bisson, Regis [Aix-Marseille Universite, PIIM, CNRS, UMR 7345, 13397 Marseille (France)

    2013-05-15

    We report the design and characterization of a new molecular-beam/surface-science apparatus for quantum state-resolved studies of gas/surface reaction dynamics combining optical state-specific reactant preparation in a molecular beam by rapid adiabatic passage with detection of surface-bound reaction products by reflection absorption infrared spectroscopy (RAIRS). RAIRS is a non-invasive infrared spectroscopic detection technique that enables online monitoring of the buildup of reaction products on the target surface during reactant deposition by a molecular beam. The product uptake rate obtained by calibrated RAIRS detection yields the coverage dependent state-resolved reaction probability S({theta}). Furthermore, the infrared absorption spectra of the adsorbed products obtained by the RAIRS technique provide structural information, which help to identify nascent reaction products, investigate reaction pathways, and determine branching ratios for different pathways of a chemisorption reaction. Measurements of the dissociative chemisorption of methane on Pt(111) with this new apparatus are presented to illustrate the utility of RAIRS detection for highly detailed studies of chemical reactions at the gas/surface interface.

  13. Catheter based mid-infrared reflectance and reflectance generated absorption spectroscopy

    Science.gov (United States)

    Holman, Hoi-Ying N

    2013-10-29

    A method of characterizing conditions in a tissue, by (a) providing a catheter that has a light source that emits light in selected wavenumbers within the range of mid-IR spectrum; (b) directing the light from the catheter to an area of tissue at a location inside a blood vessel of a subject; (c) collecting light reflected from the location and generating a reflectance spectra; and (d) comparing the reflectance spectra to a reference spectra of normal tissue, whereby a location having an increased number of absorbance peaks at said selected wavenumbers indicates a tissue inside the blood vessel containing a physiological marker for atherosclerosis.

  14. Determination of protein concentration in raw milk by mid-infrared fourier transform infrared/attenuated total reflectance spectroscopy.

    Science.gov (United States)

    Etzion, Y; Linker, R; Cogan, U; Shmulevich, I

    2004-09-01

    This study investigates the potential use of attenuated total reflectance spectroscopy in the mid-infrared range for determining protein concentration in raw cow milk. The determination of protein concentration is based on the characteristic absorbance of milk proteins, which includes 2 absorbance bands in the 1500 to 1700 cm(-1) range, known as the amide I and amide II bands, and absorbance in the 1060 to 1100 cm(-1) range, which is associated with phosphate groups covalently bound to casein proteins. To minimize the influence of the strong water band (centered around 1640 cm(-1)) that overlaps with the amide I and amide II bands, an optimized automatic procedure for accurate water subtraction was applied. Following water subtraction, the spectra were analyzed by 3 methods, namely simple band integration, partial least squares (PLS) and neural networks. For the neural network models, the spectra were first decomposed by principal component analysis (PCA), and the neural network inputs were the spectra principal components scores. In addition, the concentrations of 2 constituents expected to interact with the protein (i.e., fat and lactose) were also used as inputs. These approaches were tested with 235 spectra of standardized raw milk samples, corresponding to 26 protein concentrations in the 2.47 to 3.90% (weight per volume) range. The simple integration method led to very poor results, whereas PLS resulted in prediction errors of about 0.22% protein. The neural network approach led to prediction errors of 0.20% protein when based on PCA scores only, and 0.08% protein when lactose and fat concentrations were also included in the model. These results indicate the potential usefulness of Fourier transform infrared/attenuated total reflectance spectroscopy for rapid, possibly online, determination of protein concentration in raw milk.

  15. Evaluation of apparent viscosity of Para rubber latex by diffuse reflection near-infrared spectroscopy.

    Science.gov (United States)

    Sirisomboon, Panmanas; Chowbankrang, Rawiphan; Williams, Phil

    2012-05-01

    Near-infrared spectroscopy in diffuse reflection mode was used to evaluate the apparent viscosity of Para rubber field latex and concentrated latex over the wavelength range of 1100 to 2500 nm, using partial least square regression (PLSR). The model with ten principal components (PCs) developed using the raw spectra accurately predicted the apparent viscosity with correlation coefficient (r), standard error of prediction (SEP), and bias of 0.974, 8.6 cP, and -0.4 cP, respectively. The ratio of the SEP to the standard deviation (RPD) and the ratio of the SEP to the range (RER) for the prediction were 4.4 and 16.7, respectively. Therefore, the model can be used for measurement of the apparent viscosity of field latex and concentrated latex in quality assurance and process control in the factory.

  16. Rapid biochemical methane potential prediction of urban organic waste with near-infrared reflectance spectroscopy

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Triolo, Jin Mi; Boldrin, Alessio

    2017-01-01

    . The aim of the present study is to develop a fast and reliable model based on near-infrared reflectance spectroscopy (NIRS) for the BMP prediction of urban organic waste (UOW). The model comprised 87 UOW samples. Additionally, 88 plant biomass samples were included, to develop a combined model predicting...... BMP. The coefficient of determination (R2) and root mean square error in prediction (RMSEP) of the UOW model were 0.88 and 44 mL CH4/g VS, while the combined model was 0.89 and 50 mL CH4/g VS. Improved model performance was obtained for the two individual models compared to the combined version...

  17. Quality Control of Valerianae Radix by Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) Spectroscopy.

    Science.gov (United States)

    Nikzad-Langerodi, Ramin; Arth, Katharina; Klatte-Asselmeyer, Valerie; Bressler, Sabine; Saukel, Johannes; Reznicek, Gottfried; Dobeš, Christoph

    2018-04-01

    (Acetoxy-)valerenic acid and total essential oil content are important quality attributes of pharmacy grade valerian root (Valerianae radix). Traditional analysis of these quantities is time-consuming and necessitates (harmful) solvents. Here we investigated an application of attenuated total reflection Fourier transform infrared spectroscopy for extractionless analysis of these quality attributes on a representative sample comprising 260 wild-crafted individuals covering the Central European taxonomic diversity of the Valeriana officinalis L. s. l. species aggregate with its three major ploidy cytotypes (i.e., di-, tetra- and octoploid). Calibration models were built by orthogonal partial least squares regression for quantitative analysis of (acetoxy-)valerenic acid and total essential oil content. For the latter, we propose a simplistic protocol involving apolar extraction followed by gas chromatography as a reference method for multivariate calibration in order to handle the analysis of samples taken from individual plants. We found good predictive ability of chemometric models for quantification of valerenic acid, acetoxyvalerenic acid, total sesquiterpenoid acid, and essential oil content with a root mean squared error of cross-validation of 0.064, 0.043, and 0.09 and root mean squared error of prediction of 0.066, 0.057, and 0.09 (% content), respectively. Orthogonal partial least squares discriminant analysis revealed good discriminability between the most productive phenotype (i.e., the octoploid cytotype) in terms of sesquiterpenoid acids, and the less productive ones (i.e., di- and tetraploid). All in all, our results demonstrate the application of attenuated total reflection Fourier transform infrared spectroscopy for rapid, extractionless estimation of the most important quality attributes of valerian root and minimally invasive identification of the most productive phenotype in terms of sesquiterpenoid acids. Georg Thieme Verlag KG Stuttgart · New

  18. Identification of cattle, llama and horse meat by near infrared reflectance or transflectance spectroscopy.

    Science.gov (United States)

    Mamani-Linares, L W; Gallo, C; Alomar, D

    2012-02-01

    Visible and near infrared reflectance spectroscopy (VIS-NIRS) was used to discriminate meat and meat juices from three livestock species. In a first trial, samples of Longissimus lumborum muscle, corresponding to beef (31) llamas (21) and horses (27), were homogenised and their spectra collected in reflectance (NIRSystems 6500 scanning monochromator, in the range of 400-2500 nm). In the second trial, samples of meat juice (same muscle) from the same species (20 beef, 19 llama and 19 horse) were scanned in folded transmission (transflectance). Discriminating models (PLS regression) were developed against "dummy" variables, testing different mathematical treatments of the spectra. Best models indentified the species of almost all samples by their meat (reflectance) or meat juice (transflectance) spectra. A few (three of beef and one of llama, for meat samples; one of beef and one of horse, for juice samples) were classified as uncertain. It is concluded that NIRS is an effective tool to recognise meat and meat juice from beef, llama and horses. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Attenuated total internal reflection Fourier transform infrared spectroscopy: a quantitative approach for kidney stone analysis.

    Science.gov (United States)

    Gulley-Stahl, Heather J; Haas, Jennifer A; Schmidt, Katherine A; Evan, Andrew P; Sommer, André J

    2009-07-01

    The impact of kidney stone disease is significant worldwide, yet methods for quantifying stone components remain limited. A new approach requiring minimal sample preparation for the quantitative analysis of kidney stone components has been investigated utilizing attenuated total internal reflection Fourier transform infrared spectroscopy (ATR-FT-IR). Calcium oxalate monohydrate (COM) and hydroxylapatite (HAP), two of the most common constituents of urinary stones, were used for quantitative analysis. Calibration curves were constructed using integrated band intensities of four infrared absorptions versus concentration (weight %). The correlation coefficients of the calibration curves range from 0.997 to 0.93. The limits of detection range from 0.07 +/- 0.02% COM/HAP where COM is the analyte and HAP is the matrix, to 0.26 +/- 0.07% HAP/COM where HAP is the analyte and COM is the matrix. This study shows that linear calibration curves can be generated for the quantitative analysis of stone mixtures provided the system is well understood especially with respect to particle size.

  20. Far-infrared reflection-absorption spectroscopy of amorphous and polycrystalline gallium arsenide films

    International Nuclear Information System (INIS)

    Gregory, J.R.

    1992-01-01

    We have reported far-infrared reflection absorption spectra (30-320CM -1 ) at 30 and 310K for nine films of non-stoichiometric GaAs. The FIRRAS measurements were performed using the grazing incidence FIR double-modulation spectroscopy technique first described by DaCosta and Coleman. The films were fabricated by molecular beam deposition on metallized substrates for two As/Ga molecular beam flux ratios. The films were characterized by depth profilometry, IRAS, XRD, and x-ray microprobe analysis. Film thicknesses ranged from 800 to 5800 angstrom and compositions were 45-50% As for a MB flux ratio of 0.29 and 60-70% As for a ratio of 1.12. FIRRAS measurements were made and characterizations performed for as-deposited films and for 5 hour anneals at 473, 573, 673 and 723 degrees C. Vibrational spectra of the crystallized films were interpreted in terms of the exact reflectivity of a thin dielectric film on a conducting substrate, using a classical Lorentzian dielectric function for the response of the film. Resonances appearing in the open-quote forbidden close-quote region between the TO and LO frequencies were modelled with an effective medium approximation and are interpreted as arising from small-scale surface roughness. The behavior of the amorphous film spectra were examined within two models. The effective force constant model describes the variation of the reflection-absorption maxima with measured crystallite size in terms of the effective vibration frequency of 1-D atomic chains having force constants distributed according to the parameters of the crystalline-to-amorphous relaxation length and the crystalline to amorphous force constant ratio. The dielectric function continuum model uses the relaxation of the crystal momentum selection rule to calculate the reflection-absorption spectrum based on a dielectric function in which the oscillator strength is the normalized product of a constant dipole strength and the smoothed vibrational density of states

  1. Diffuse-reflectance fourier-transform mid-infrared spectroscopy as a method of characterizing changes in soil organic matter

    Science.gov (United States)

    Diffuse-Reflectance Fourier-Transform Mid-Infrared Spectroscopy (MidIR) can identify the presence of important organic functional groups in soil organic matter (SOM). Soils contain myriad organic and inorganic components that absorb in the MidIR so spectral interpretation needs to be validated in or...

  2. Secondary cell wall development in cotton fibers as examined with attenuated total reflection Fourier transform infrared spectroscopy

    Science.gov (United States)

    Cotton fibers harvested at 18, 20, 24, 28, 32, 36 and 40 days after flowering were examined using attenuated total reflection Fourier transform-infrared (ATR FT-IR) spectroscopy. The selected harvesting points coincide with secondary cell wall (SCW) development in the fibers. Progressive but moderat...

  3. Prediction of biogas yield and its kinetics in reed canary grass using near infrared reflectance spectroscopy and chemometrics

    DEFF Research Database (Denmark)

    Kandel, Tanka Prasad; Gislum, René; Jørgensen, Uffe

    2013-01-01

    A rapid method is needed to assess biogas and methane yield potential of various kinds of substrate prior to anaerobic digestion. This study reports near infrared reflectance spectroscopy (NIRS) as a rapid alternative method to the conventional batch methods for prediction of specific biogas yield...

  4. Conformational aspects of proteins at the air/water interface studied by infrared reflection-adsorption spectroscopy

    NARCIS (Netherlands)

    Martin, A.H.; Meinders, M.B.J.; Bos, M.A.; Cohen Stuart, M.A.; Vliet, van T.

    2003-01-01

    From absorption spectra obtained with infrared reflection-absorption spectroscopy (IRRAS), it is possible to obtain information on conformational changes at a secondary folding level of proteins adsorbed at the air/water interface. In addition, information on protein concentration at the interface

  5. Conformational aspects of proteins at the air/water interface studied by infrared reflection-absorption spectroscopy

    NARCIS (Netherlands)

    Martin, A.H.; Meinders, M.B.J.; Bos, M.A.; Cohen Stuart, M.A.; Vliet, T. van

    2003-01-01

    From absorption spectra obtained with infrared reflection - absorption spectroscopy (IRRAS), it is possible to obtain information on conformational changes at a secondary folding level of proteins adsorbed at the air/water interface. In addition, information on protein concentration at the interface

  6. Quantification of betaglucans, lipid and protein contents in whole oat groats (Avena sativa L.) using near infrared reflectance spectroscopy

    Science.gov (United States)

    Whole oat has been described as an important healthy food for humans due to its beneficial nutritional components. Near infrared reflectance spectroscopy (NIRS) is a powerful, fast, accurate and non-destructive analytical tool that can be substituted for some traditional chemical analysis. A total o...

  7. The application of Near Infrared Reflectance Spectroscopy (NIRS) for the quantitative analysis of hydrocortisone in primary materials

    OpenAIRE

    A. PITTAS; C. SERGIDES; K. NIKOLICH

    2001-01-01

    Near Infrared Reflectance Spectroscopy (NIRS), coupled with fiber optic probes, has been shown to be a quick and reliable analytical tool for quality assurance and quality control in the pharmaceutical industry, both for verifications of raw materials and quantification of the active ingredients in final products. In this paper, a typical pharmaceutical product, hydrocortisone sodium succinate, is used as an example for the application of NIR spectroscopy for quality control. In order to deve...

  8. Analysis of ecstasy tablets: comparison of reflectance and transmittance near infrared spectroscopy.

    Science.gov (United States)

    Schneider, Ralph Carsten; Kovar, Karl-Artur

    2003-07-08

    Calibration models for the quantitation of commonly used ecstasy substances have been developed using near infrared spectroscopy (NIR) in diffuse reflectance and in transmission mode by applying seized ecstasy tablets for model building and validation. The samples contained amphetamine, N-methyl-3,4-methylenedioxy-amphetamine (MDMA) and N-ethyl-3,4-methylenedioxy-amphetamine (MDE) in different concentrations. All tablets were analyzed using high performance liquid chromatography (HPLC) with diode array detection as reference method. We evaluated the performance of each NIR measurement method with regard to its ability to predict the content of each tablet with a low root mean square error of prediction (RMSEP). Best calibration models could be generated by using NIR measurement in transmittance mode with wavelength selection and 1/x-transformation of the raw data. The models build in reflectance mode showed higher RMSEPs using as data pretreatment, wavelength selection, 1/x-transformation and a second order Savitzky-Golay derivative with five point smoothing was applied to obtain the best models. To estimate the influence of inhomogeneities in the illegal tablets, a calibration of the destroyed, i.e. triturated samples was build and compared to the corresponding data of the whole tablets. The calibrations using these homogenized tablets showed lower RMSEPs. We can conclude that NIR analysis of ecstasy tablets in transmission mode is more suitable than measurement in diffuse reflectance to obtain quantification models for their active ingredients with regard to low errors of prediction. Inhomogeneities in the samples are equalized when measuring the tablets as powdered samples.

  9. [Near-infrared reflectance spectroscopy predicts protein, moisture and ash in beans].

    Science.gov (United States)

    Gao, Huiyu; Wang, Guodong; Men, Jianhua; Wang, Zhu

    2017-05-01

    To explore the potential of near-infrared reflectance( NIR)spectroscopy to determine macronutrient contents in beans. NIR spectra and analytical measurements of protein, moisture and ash were collected from 70 kinds of beans. Reference methods were used to analyze all the ground beans samples. NIR spectra on intact and ground beans samples were registered. Partial least-squares( PLS)regression models were developed with principal components analysis( PCA) to assign 49 bean accessions to a calibration data set and 21 accessions to an external validation set. For intact beans, the relative predictive determinant( RPD) values for protein and ash( 3. 67 and 3. 97, respectively) were good for screening. RPD value for moisture was only 1. 39, which was not recommended. For ground beans, the RPD values for protein, moisture and ash( 6. 63, 5. 25 and 3. 57, respectively) were good enough for screening. The protein, moisture and ash levels for intact and ground beans were all significantly correlated( P beans with no or easy sample preparation.

  10. Quality evaluation of regional forage resources by means of near infrared reflectance spectroscopy

    Directory of Open Access Journals (Sweden)

    Bruno Ronchi

    2010-01-01

    Full Text Available Quality parameters of grassland and pasture samples collected during a three-year period at two environmentally andgeographically different areas were analysed by Near Infrared Reflectance Spectroscopy (NIRS. Chemical analysis forcrude protein (CP, crude fibre (CF, neutral detergent fibre (NDF, acid detergent fibre (ADF, acid detergent lignin (ADLand crude ash (ASH carried out on two-thirds of the samples were used in calibration processes. The remaining onethirdof the data was used to validate the best calibrations obtained. Samples selection is discussed. Different math pretreatments(derivative, gap, primary smoothing and secondary smoothing, light scattering correction methods and calibrationalgorithms were tested to achieve the better predictive performances. We obtained the best results using differentregression algorithms to correlate spectral information to chemical data. For CP (R2 = 0.94, SEP=1.3, NDF (R2 =0.95, SEP = 2.14 and ADF (R2 = 0.92, SEP=2.06 Multiple Linear Regression (MLR models fit chemical data better thanMean Partial Least Square (MPLS regression. A molecular basis explanation of wavelengths selected was carried out.MPLS models worked well for CF (R2 = 0.93, SEP=1.57, and ASH (R2 = 0.95, SEP=1.17 while poor calibrations wereobtained for ADL using both algorithms. To confirm the reliability of the models developed, uncertainties of predictionswere compared with findings on nutritional variations and animal performances.

  11. [Progress in application of near infrared reflectance spectroscopy to the study of ruminant nutrition].

    Science.gov (United States)

    Guo, Xu-Sheng; Shang, Zhan-Huan; Fang, Xiang-Wen; Long, Rui-Jun

    2009-03-01

    The near infrared reflectance spectroscopy (NIRS) technique has been widely used in the study of ruminant nutrition with many of its operational merits such as facility, shortcut and accuracy, etc. Study suggested that the standard error of cross-validation (SECV) ranges from 1.6% to 2.8% in predicting organic matter digestion of ruminant diet by using the NIRS technique; the chemical and biological compositions and the microbial protein proportion in the duodenal digesta can be predicted accurately using the NIRS. However, the kinetic parameters of degradation are not well predicted; The prediction of intake of stall feeding animals by using NIRS is similar to the determination of in vivo method, but the standard error of prediction is about 14% when using the NIRS to predict intake of grazing animals. All of the studies suggest that big progress has been made in using NIRS technique to predict feed digestion and evaluate the diet quality and intake of ruminant animals, which also suggest that the NIRS technique has a wide prospect in the study of ruminant nutrition.

  12. Crop/weed discrimination using near-infrared reflectance spectroscopy (NIRS)

    Science.gov (United States)

    Zhang, Yun; He, Yong

    2006-09-01

    The traditional uniform herbicide application often results in an over chemical residues on soil, crop plants and agriculture produce, which have imperiled the environment and food security. Near-infrared reflectance spectroscopy (NIRS) offers a promising means for weed detection and site-specific herbicide application. In laboratory, a total of 90 samples (30 for each species) of the detached leaves of two weeds, i.e., threeseeded mercury (Acalypha australis L.) and fourleafed duckweed (Marsilea quadrfolia L.), and one crop soybean (Glycine max) was investigated for NIRS on 325- 1075 nm using a field spectroradiometer. 20 absorbance samples of each species after pretreatment were exported and the lacked Y variables were assigned independent values for partial least squares (PLS) analysis. During the combined principle component analysis (PCA) on 400-1000 nm, the PC1 and PC2 could together explain over 91% of the total variance and detect the three plant species with 98.3% accuracy. The full-cross validation results of PLS, i.e., standard error of prediction (SEP) 0.247, correlation coefficient (r) 0.954 and root mean square error of prediction (RMSEP) 0.245, indicated an optimum model for weed identification. By predicting the remaining 10 samples of each species in the PLS model, the results with deviation presented a 100% crop/weed detection rate. Thus, it could be concluded that PLS was an available alternative of for qualitative weed discrimination on NTRS.

  13. Detection of sibutramine in adulterated dietary supplements using attenuated total reflectance-infrared spectroscopy.

    Science.gov (United States)

    Deconinck, E; Cauwenbergh, T; Bothy, J L; Custers, D; Courselle, P; De Beer, J O

    2014-11-01

    Sibutramine is one of the most occurring adulterants encountered in dietary supplements with slimming as indication. These adulterated dietary supplements often contain a herbal matrix. When customs intercept these kind of supplements it is almost impossible to discriminate between the legal products and the adulterated ones, due to misleading packaging. Therefore in most cases these products are confiscated and send to laboratories for analysis. This results inherently in the confiscation of legal, non-adulterated products. Therefore there is a need for easy to use equipment and techniques to perform an initial screening of samples. Attenuated total reflectance-infrared (ATR-IR) spectroscopy was evaluated for the detection of sibutramine in adulterated dietary supplements. Data interpretation was performed using different basic chemometric techniques. It was found that the use of ATR-IR combined with the k-Nearest Neighbours (k-NN) was able to detect all adulterated dietary supplements in an external test set and this with a minimum of false positive results. This means that a small amount of legal products will still be confiscated and analyzed in a laboratory to be found negative, but no adulterated samples will pass the initial ATR-IR screening. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Phase transitions of amorphous solid acetone in confined geometry investigated by reflection absorption infrared spectroscopy.

    Science.gov (United States)

    Shin, Sunghwan; Kang, Hani; Kim, Jun Soo; Kang, Heon

    2014-11-26

    We investigated the phase transformations of amorphous solid acetone under confined geometry by preparing acetone films trapped in amorphous solid water (ASW) or CCl4. Reflection absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD) were used to monitor the phase changes of the acetone sample with increasing temperature. An acetone film trapped in ASW shows an abrupt change in the RAIRS features of the acetone vibrational bands during heating from 80 to 100 K, which indicates the transformation of amorphous solid acetone to a molecularly aligned crystalline phase. Further heating of the sample to 140 K produces an isotropic solid phase, and eventually a fluid phase near 157 K, at which the acetone sample is probably trapped in a pressurized, superheated condition inside the ASW matrix. Inside a CCl4 matrix, amorphous solid acetone crystallizes into a different, isotropic structure at ca. 90 K. We propose that the molecularly aligned crystalline phase formed in ASW is created by heterogeneous nucleation at the acetone-water interface, with resultant crystal growth, whereas the isotropic crystalline phase in CCl4 is formed by homogeneous crystal growth starting from the bulk region of the acetone sample.

  15. Predicting glycogen concentration in the foot muscle of abalone using near infrared reflectance spectroscopy (NIRS).

    Science.gov (United States)

    Fluckiger, Miriam; Brown, Malcolm R; Ward, Louise R; Moltschaniwskyj, Natalie A

    2011-06-15

    Near infrared reflectance spectroscopy (NIRS) was used to predict glycogen concentrations in the foot muscle of cultured abalone. NIR spectra of live, shucked and freeze-dried abalones were modelled against chemically measured glycogen data (range: 0.77-40.9% of dry weight (DW)) using partial least squares (PLS) regression. The calibration models were then used to predict glycogen concentrations of test abalone samples and model robustness was assessed from coefficient of determination of the validation (R2(val)) and standard error of prediction (SEP) values. The model for freeze-dried abalone gave the best prediction (R2(val) 0.97, SEP=1.71), making it suitable for quantifying glycogen. Models for live and shucked abalones had R2(val) of 0.86 and 0.90, and SEP of 3.46 and 3.07 respectively, making them suitable for producing estimations of glycogen concentration. As glycogen is a taste-active component associated with palatability in abalone, this study demonstrated the potential of NIRS as a rapid method to monitor the factors associated with abalone quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Forensic Hair Differentiation Using Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy.

    Science.gov (United States)

    Manheim, Jeremy; Doty, Kyle C; McLaughlin, Gregory; Lednev, Igor K

    2016-07-01

    Hair and fibers are common forms of trace evidence found at crime scenes. The current methodology of microscopic examination of potential hair evidence is absent of statistical measures of performance, and examiner results for identification can be subjective. Here, attenuated total reflection (ATR) Fourier transform-infrared (FT-IR) spectroscopy was used to analyze synthetic fibers and natural hairs of human, cat, and dog origin. Chemometric analysis was used to differentiate hair spectra from the three different species, and to predict unknown hairs to their proper species class, with a high degree of certainty. A species-specific partial least squares discriminant analysis (PLSDA) model was constructed to discriminate human hair from cat and dog hairs. This model was successful in distinguishing between the three classes and, more importantly, all human samples were correctly predicted as human. An external validation resulted in zero false positive and false negative assignments for the human class. From a forensic perspective, this technique would be complementary to microscopic hair examination, and in no way replace it. As such, this methodology is able to provide a statistical measure of confidence to the identification of a sample of human, cat, and dog hair, which was called for in the 2009 National Academy of Sciences report. More importantly, this approach is non-destructive, rapid, can provide reliable results, and requires no sample preparation, making it of ample importance to the field of forensic science. © The Author(s) 2016.

  17. Noninvasive method for the assessment of dermal uptake of pesticides using attenuated total reflectance infrared spectroscopy.

    Science.gov (United States)

    Carden, Angela; Yost, Michael G; Fenske, Richard A

    2005-03-01

    Dermal absorption of pesticides is a primary exposure route for agricultural workers, but is not well characterized. Current measurement techniques are either invasive, such as tape-stripping, or require extensive sample preparation or analysis time, such as urinary metabolite monitoring or wipe sampling followed by gas chromatography analysis. We present the application of a noninvasive, spectroscopic approach for the measurement of pesticide absorption into skin. Attenuated total reflectance infrared spectroscopy (ATR-IR) was used to monitor directly the absorption of two pesticides--captan and azinphos-methyl--in ten volunteers over 20 min under occlusive conditions. We found substantial variability in absorption across subjects. Our results were comparable to those measured by the more traditional method of wipe-sampling followed by extraction and gas chromatography analysis. Multivariate data analysis, in the form of multivariate curve resolution (MCR), is a novel addition to this type of experiment, yielding time-resolved information unachievable by standard methods. These data are potentially more informative than the monitoring of blood or urinary metabolites because they can be acquired in essentially real-time, allowing observations of pesticide absorption on a rapid timescale rather than over hours or days.

  18. Near infrared reflectance spectroscopy for the fast identification of PVC-based films.

    Science.gov (United States)

    Laasonen, M; Rantanen, J; Harmia-Pulkkinen, T; Michiels, E; Hiltunen, R; Räsänen, M; Vuorela, H

    2001-07-01

    Near infrared (NIR) reflectance spectroscopy was used to develop a non-destructive and rapid qualitative method for the analysis of plastic films used by the pharmaceutical industry for blistering. Three types of films were investigated: 250 microm PVC [poly(vinyl chloride)] films, 250 microm PVC films coated with 40 g m(-2) of PVDC [poly(vinylidene dichloride)] and 250 microm PVC films coated with 5 g m(-2) of TE (Thermoelast) and 90 g m(-2) of PVDC. Three analyses were carried out using different pre-treatment options and a PLS (partial least squares) algorithm. Each analysis was aimed at identifying one type of film and rejecting all types of false sample (different thickness, colour or layer). True and false samples from four plastics manufacturers were included in the calibration sets in order to obtain robust methods that were suitable regardless of the supplier. Specificity was demonstrated by testing validation sets against the methods. The tests showed 0% of type I (false negative identification) and 1% of type II errors (false positive identification) for the PVC method, 13 and 3%, respectively, for the PVC-PVDC method and no error for the PVC-TE-PVDC method. Type II errors, mostly due to the slight sensitivity of the methods to film thickness, are easily corrected by simple thickness measurements. This study demonstrates that NIR spectroscopy is an excellent tool for the identification of PVC-based films. The three methods can be used by the pharmaceutical industry or plastics manufacturers for the quality control of films used in blister packaging.

  19. Analysis of total oil and fatty acids composition by near infrared reflectance spectroscopy in edible nuts

    Science.gov (United States)

    Kandala, Chari V.; Sundaram, Jaya

    2014-10-01

    Near Infrared (NIR) Reflectance spectroscopy has established itself as an important tool in quantifying water and oil present in various food materials. It is rapid and nondestructive, easier to use, and does not require processing the samples with corrosive chemicals that would render them non-edible. Earlier, the samples had to be ground into powder form before making any measurements. With the development of new soft ware packages, NIR techniques could now be used in the analysis of intact grain and nuts. While most of the commercial instruments presently available work well with small grain size materials such as wheat and corn, the method present here is suitable for large kernel size products such as shelled or in-shell peanuts. Absorbance spectra were collected from 400 nm to 2500 nm using a NIR instrument. Average values of total oil contents (TOC) of peanut samples were determined by standard extraction methods, and fatty acids were determined using gas chromatography. Partial least square (PLS) analysis was performed on the calibration set of absorption spectra, and models were developed for prediction of total oil and fatty acids. The best model was selected based on the coefficient of determination (R2), Standard error of prediction (SEP) and residual percent deviation (RPD) values. Peanut samples analyzed showed RPD values greater than 5.0 for both absorbance and reflectance models and thus could be used for quality control and analysis. Ability to rapidly and nondestructively measure the TOC, and analyze the fatty acid composition, will be immensely useful in peanut varietal improvement as well as in the grading process of grain and nuts.

  20. Non-invasive identification of organic materials in historical stringed musical instruments by reflection infrared spectroscopy: a methodological approach.

    Science.gov (United States)

    Invernizzi, Claudia; Daveri, Alessia; Vagnini, Manuela; Malagodi, Marco

    2017-05-01

    The analysis of historical musical instruments is becoming more relevant and the interest is increasingly moving toward the non-invasive reflection FTIR spectroscopy, especially for the analysis of varnishes. In this work, a specific infrared reflectance spectral library of organic compounds was created with the aim of identifying musical instrument materials in a totally non-invasive way. The analyses were carried out on pure organic compounds, as bulk samples and laboratory wooden models, to evaluate the diagnostic reflection mid-infrared (MIR) bands of proteins, polysaccharides, lipids, and resins by comparing reflection spectra before and after the KK correction. This methodological approach was applied to real case studies represented by four Stradivari violins and a Neapolitan mandolin.

  1. Determining the mineral composition in Cucurbita pepo fruit using near infrared reflectance spectroscopy.

    Science.gov (United States)

    Martínez-Valdivieso, Damián; Font, Rafael; Gómez, Pedro; Blanco-Díaz, Teresa; Del Río-Celestino, Mercedes

    2014-12-01

    Efforts through conventional breeding to improve the mineral content in horticultural crops have not always been successful mainly due to the fact that standard analytical methods are both costly and time-consuming. We investigated the feasibility of applying near infrared reflectance spectroscopy (NIRS) to the estimation of essential mineral composition in the skin and flesh of summer squash fruits (Cucurbita pepo subsp. pepo) using a 200-sample set from diverse morphotypes. The coefficients of determination in the external validation (R(2) VAL) obtained for the skin and flesh of the fruit were: total mineral content, 0.84 and 0.70; P, 0.74 and 0.62; K, 0.83 and 0.67; Ca, 0.57 and 0.60; Mg, 0.78 and 0.45; Fe, 0.78 and 0.65; Cu, 0.67 and 0.66; Mn, 0.67 and 0.64; Zn, 0.80 and 0.79 and Na, 0.33 and 0.33; respectively. NIRS combined with different spectral transformations by modified partial least-squares (MPLS) regression has shown to be useful in determining the mineral composition of summer squash fruit, being a fast and low-cost analytical technique. Components such as chlorophyll, starch and lipids were used by MPLS for modelling the predicting equations. The promotion of micronutrient-rich summer squash varieties could have a significant long-term beneficial impact on the health of mineral deficient human populations. © 2014 Society of Chemical Industry.

  2. Suitability of faecal near-infrared reflectance spectroscopy (NIRS) predictions for estimating gross calorific value

    Energy Technology Data Exchange (ETDEWEB)

    De la Roza-Delgado, B.; Modroño, S.; Vicente, F.; Martínez-Fernández, A.; Soldado, A.

    2015-07-01

    A total of 220 faecal pig and poultry samples, collected from different experimental trials were employed with the aim to demonstrate the suitability of Near Infrared Reflectance Spectroscopy (NIRS) technology for estimation of gross calorific value on faeces as output products in energy balances studies. NIR spectra from dried and grounded faeces samples were analyzed using a Foss NIRSystem 6500 instrument, scanning over the wavelength range 400-2500 nm. Validation studies for quantitative analytical models were carried out to estimate the relevance of method performance associated to reference values to obtain an appropriate, accuracy and precision. The results for prediction of gross calorific value (GCV) of NIRS calibrations obtained for individual species showed high correlation coefficients comparing chemical analysis and NIRS predictions, ranged from 0.92 to 0.97 for poultry and pig. For external validation, the ratio between the standard error of cross validation (SECV) and the standard error of prediction (SEP) varied between 0.73 and 0.86 for poultry and pig respectively, indicating a sufficiently precision of calibrations. In addition a global model to estimate GCV in both species was developed and externally validated. It showed correlation coefficients of 0.99 for calibration, 0.98 for cross-validation and 0.97 for external validation. Finally, relative uncertainty was calculated for NIRS developed prediction models with the final value when applying individual NIRS species model of 1.3% and 1.5% for NIRS global prediction. This study suggests that NIRS is a suitable and accurate method for the determination of GCV in faeces, decreasing cost, timeless and for convenient handling of unpleasant samples.. (Author)

  3. Characterization and quantitation of aprepitant drug substance polymorphs by attenuated total reflectance fourier transform infrared spectroscopy.

    Science.gov (United States)

    Helmy, Roy; Zhou, George X; Chen, Yadan W; Crocker, Louis; Wang, Tao; Wenslow, Robert M; Vailaya, Anant

    2003-02-01

    In this study, we report the use of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FT-IR) for the identification and quantitation of two polymorphs of Aprepitant, a substance P antagonist for chemotherapy-induced emesis. Mixtures of the polymorph pair were prepared by weight and ATR-FT-IR spectra of the powdered samples were obtained over the wavelength range of 700-1500 cm(-1). Significant spectral differences between the two polymorphs at 1140 cm(-1) show that ATR-FT-IR can provide definitive identification of the polymorphs. To investigate the feasibility of ATR-FT-IR for quantitation of polymorphic forms of Aprepitant, a calibration plot was constructed with known mixtures of the two polymorphs by plotting the peak ratio of the second derivative of absorbance spectra against the weight percent of form II in the polymorphic mixture. Using this novel approach, 3 wt % of one crystal form could be detected in mixtures of the two polymorphs. The accuracy of ATR-FT-IR in determining polymorph purity of the drug substance was tested by comparing the results with those obtained by X-ray powder diffractometry (XRPD). Indeed, polymorphic purity results obtained by ATR-FT-IR were found to be in good agreement with the predictions made by XRPD and compared favorably with actual values in the known mixtures. The present study clearly demonstrates the potential of ATR-FT-IR as a quick, easy, and inexpensive alternative to XRPD for the determination of polymorphic identity and purity of solid drug substances. The technique is ideally suited for polymorph analysis, because it is precise, accurate, and requires minimal sample preparation.

  4. Non-invasive identification of metal-oxalate complexes on polychrome artwork surfaces by reflection mid-infrared spectroscopy.

    Science.gov (United States)

    Monico, Letizia; Rosi, Francesca; Miliani, Costanza; Daveri, Alessia; Brunetti, Brunetto G

    2013-12-01

    In this work a reflection mid-infrared spectroscopy study of twelve metal-oxalate complexes, of interest in art conservation science as alteration compounds, was performed. Spectra of the reference materials highlighted the presence of derivative-like and/or inverted features for the fundamental vibrational modes as result of the main contribution from the surface component of the reflected light. In order to provide insights in the interpretation of theses spectral distortions, reflection spectra were compared with conventional transmission ones. The Kramers-Kronig (KK) algorithm, employed to correct for the surface reflection distortions, worked properly only for the derivative-like bands. Therefore, to pay attention to the use of this algorithm when interpreting the reflection spectra is recommended. The outcome of this investigation was exploited to discriminate among different oxalates on thirteen polychrome artworks analyzed in situ by reflection mid-infrared spectroscopy. The visualization of the νs(CO) modes (1400-1200 cm(-1)) and low wavenumber bands (below 900 cm(-1)) in the raw reflection profiles allowed Ca, Cu and Zn oxalates to be identified. Further information about the speciation of different hydration forms of calcium oxalates were obtained by using the KK transform. The work proves reflection mid-infrared spectroscopy to be a reliable and sensitive spectro-analytical method for identifying and mapping different metal-oxalate alteration compounds on the surface of artworks, thus providing conservation scientists with a non-invasive tool to obtain information on the state of conservation and causes of alteration of artworks. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Reflectance and Thermal Infrared Spectroscopy of Mars: Relationship Between ISM and TES for Compositional Determinations

    Science.gov (United States)

    Boyce, Joseph (Technical Monitor); Mustard, John

    2004-01-01

    Reflectance spectroscopy has demonstrated that high albedo surfaces on Mars contain heavily altered materials with some component of hematite, poorly crystalline ferric oxides, and an undefined silicate matrix. The spectral properties of many low albedo regions indicate crystalline basalts containing both low and high calcium pyroxene, a mineralogy consistent with the basaltic SNC meteorites. The Thermal Emission Spectrometer (TES) experiment on the Mars Geochemical Surveyor has acquired critical new data relevant to surface composition and mineralogy, but in a wavelength region that is complementary to reflectance spectroscopy. The essence of the completed research was to analyze TES data in the context of reflectance data obtained by the French ISM imaging spectrometer experiment in 1989. This approach increased our understanding of the complementary nature of these wavelength regions for mineralogic determinations using actual observations of the martian surface. The research effort focused on three regions of scientific importance: Syrtis Major-Isidis Basin, Oxia Palus-Arabia, and Valles Marineris. In each region distinct spatial variations related to reflectance, and in derived mineralogic information and interpreted compositional units were analyzed. In addition, specific science questions related to the composition of volcanics and crustal evolution, soil compositions and pedogenic processes, and the relationship between pristine lithologies and weathering provided an overall science-driven framework for the work. The detailed work plan involved colocation of TES and ISM data, extraction of reflectance and emissivity spectra from areas of known reflectance variability, and quantitative analysis using factor analysis and statistical techniques to determine the degree of correspondence between these different wavelength regions. Identified coherent variations in TES spectroscopy were assessed against known atmospheric effects to validate that the variations

  6. Identification of Uranium Minerals in Natural U-Bearing Rocks Using Infrared Reflectance Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Beiswenger, Toya N. [Pacific Northwest National Laboratory, Richland, WA, USA; Gallagher, Neal B. [Eigenvector Research, Inc., Manson, WA, USA; Myers, Tanya L. [Pacific Northwest National Laboratory, Richland, WA, USA; Szecsody, James E. [Pacific Northwest National Laboratory, Richland, WA, USA; Tonkyn, Russell G. [Pacific Northwest National Laboratory, Richland, WA, USA; Su, Yin-Fong [Pacific Northwest National Laboratory, Richland, WA, USA; Sweet, Lucas E. [Pacific Northwest National Laboratory, Richland, WA, USA; Lewallen, Tricia A. [Pacific Northwest National Laboratory, Richland, WA, USA; Johnson, Timothy J. [Pacific Northwest National Laboratory, Richland, WA, USA

    2017-10-24

    The identification of minerals, including uranium-bearing minerals, is traditionally a labor-intensive-process using x-ray diffraction (XRD), fluorescence, or other solid-phase and wet chemical techniques. While handheld XRD and fluorescence instruments can aid in field identification, handheld infrared reflectance spectrometers can also be used in industrial or field environments, with rapid, non-destructive identification possible via spectral analysis of the solid’s reflectance spectrum. We have recently developed standard laboratory measurement methods for the infrared (IR) reflectance of solids and have investigated using these techniques for the identification of uranium-bearing minerals, using XRD methods for ground-truth. Due to the rich colors of such species, including distinctive spectroscopic signatures in the infrared, identification is facile and specific, both for samples that are pure or are partially composed of uranium (e.g. boltwoodite, schoepite, tyuyamunite, carnotite, etc.) or non-uranium minerals. The method can be used to detect not only pure and partial minerals, but is quite sensitive to chemical change such as hydration (e.g. schoepite). We have further applied statistical methods, in particular classical least squares (CLS) and multivariate curve resolution (MCR) for discrimination of such uranium minerals and two uranium pure chemicals (U3O8 and UO2) against common background materials (e.g. silica sand, asphalt, calcite, K-feldspar) with good success. Each mineral contains unique infrared spectral features; some of the IR features are similar or common to entire classes of minerals, typically arising from similar chemical moieties or functional groups in the minerals: phosphates, sulfates, carbonates, etc. These characteristic 2 infrared bands generate the unique (or class-specific) bands that distinguish the mineral from the interferents or backgrounds. We have observed several cases where the chemical moieties that provide the

  7. Trasmission and Reflection (ATR)Far-Infrared Spectroscopy Applied in the Analysis of Cultural Heritage Materials

    OpenAIRE

    Kendix, Elsebeth Langholz

    2009-01-01

    FIR spectroscopy is an alternative way of collecting spectra of many inorganic pigments and corrosion products found on art objects, which is not normally observed in the MIR region. Most FIR spectra are traditionally collected in transmission mode but as a real novelty it is now also possible to record FIR spectra in ATR (Attenuated Total Reflectance) mode. In FIR transmission we employ polyethylene (PE) for preparation of pellets by embedding the sample in PE. Unfortunately, ...

  8. CO 2 Capture Capacity and Swelling Measurements of Liquid-like Nanoparticle Organic Hybrid Materials via Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy

    KAUST Repository

    Park, Youngjune; Shin, Dolly; Jang, Young Nam; Park, Ah-Hyung Alissa

    2012-01-01

    attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy. Simultaneous measurements of CO 2 capture capacity and swelling behaviors of polyetheramine (Jeffamine M-2070) and its corresponding NOHMs (NOHM-I-PE2070) were reported

  9. [Near infrared reflectance spectroscopy (NIRS): a novel approach to reconstructing historical changes of primary productivity in Antarctic lake].

    Science.gov (United States)

    Chen, Qian-Qian; Liu, Xiao-Dong; Liu, Wen-Qi; Jiang, Shan

    2011-10-01

    Compared with traditional chemical analysis methods, reflectance spectroscopy has the advantages of speed, minimal or no sample preparation, non-destruction, and low cost. In order to explore the potential application of spectroscopy technology in the paleolimnological study on Antarctic lakes, we took a lake sediment core in Mochou Lake at Zhongshan Station of Antarctic, and analyzed the near infrared reflectance spectroscopy (NIRS) data in the sedimentary samples. The results showed that the factor loadings of principal component analysis (PCA) displayed very similar depth-profile change pattern with the S2 index, a reliable proxy for the change in historical lake primary productivity. The correlation analysis showed that the values of PCA factor loading and S2 were correlated significantly, suggesting that it is feasible to infer paleoproductivity changes recorded in Antarctic lakes using NIRS technology. Compared to the traditional method of the trough area between 650 and 700 nm, the authors found that the PCA statistical approach was more accurate for reconstructing the change in historical lake primary productivity. The results reported here demonstrate that reflectance spectroscopy can provide a rapid method for the reconstruction of lake palaeoenviro nmental change in the remote Antarctic regions.

  10. Effective rumen degradation of dry matter, crude protein and neutral detergent fibre in forage determined by near infrared reflectance spectroscopy

    DEFF Research Database (Denmark)

    Ohlsson, C; Houmøller, L P; Weisbjerg, Martin Riis

    2007-01-01

    The objective of the present study was to examine if near infrared reflectance spectroscopy (NIRS) could be used to predict degradation parameters and effective degradation from scans of original forage samples. Degradability of dry matter (DM), crude protein (CP) and neutral detergent fibre (NDF......) of 61 samples of perennial ryegrass (Lolium perenne L.) and orchardgrass (Dactylis glomerata L.) was tested by using the in situ technique. The grass samples were harvested at three different stages, early vegetative growth, early reproductive growth and late reproductive growth. Degradability...

  11. Classification of Fusarium-Infected Korean Hulled Barley Using Near-Infrared Reflectance Spectroscopy and Partial Least Squares Discriminant Analysis

    Directory of Open Access Journals (Sweden)

    Jongguk Lim

    2017-09-01

    Full Text Available The purpose of this study is to use near-infrared reflectance (NIR spectroscopy equipment to nondestructively and rapidly discriminate Fusarium-infected hulled barley. Both normal hulled barley and Fusarium-infected hulled barley were scanned by using a NIR spectrometer with a wavelength range of 1175 to 2170 nm. Multiple mathematical pretreatments were applied to the reflectance spectra obtained for Fusarium discrimination and the multivariate analysis method of partial least squares discriminant analysis (PLS-DA was used for discriminant prediction. The PLS-DA prediction model developed by applying the second-order derivative pretreatment to the reflectance spectra obtained from the side of hulled barley without crease achieved 100% accuracy in discriminating the normal hulled barley and the Fusarium-infected hulled barley. These results demonstrated the feasibility of rapid discrimination of the Fusarium-infected hulled barley by combining multivariate analysis with the NIR spectroscopic technique, which is utilized as a nondestructive detection method.

  12. Hollow optical-fiber based infrared spectroscopy for measurement of blood glucose level by using multi-reflection prism.

    Science.gov (United States)

    Kino, Saiko; Omori, Suguru; Katagiri, Takashi; Matsuura, Yuji

    2016-02-01

    A mid-infrared attenuated total reflection (ATR) spectroscopy system employing hollow optical fibers and a trapezoidal multi-reflection ATR prism has been developed to measure blood glucose levels. Using a multi-reflection prism brought about higher sensitivity, and the flat and wide contact surface of the prism resulted in higher measurement reproducibility. An analysis of in vivo measurements of human inner lip mucosa revealed clear signatures of glucose in the difference spectra between ones taken during the fasting state and ones taken after ingestion of glucose solutions. A calibration plot based on the absorption peak at 1155 cm(-1) that originates from the pyranose ring structure of glucose gave measurement errors less than 20%.

  13. Application of Polarization Modulated Infrared Reflection Absorption Spectroscopy for electrocatalytic activity studies of laccase adsorbed on modified gold electrodes

    International Nuclear Information System (INIS)

    Olejnik, Piotr; Pawłowska, Aleksandra; Pałys, Barbara

    2013-01-01

    Orientation of the enzyme macromolecule on the electrode surface is crucially important for the efficiency of the electron transport between the active site and electrode surface. The orientation can be controlled by affecting the surface charge and the pH of the buffer solution. In this contribution we study laccase physically adsorbed on gold surface modified by mercapto-ethanol, lipid and variously charged diazonium salts. Polarization Modulated Infrared Reflection Absorption Spectroscopy (PMIRRAS) enables the molecular orientation study of the protein molecule by comparison of the amide I to amide II band intensity ratios assuming that the protein secondary structure does not change. We observe significant differences in the intensity ratios depending on the kind of support and the enzyme deposition. The comparison of infrared spectra and cyclic voltammetry responses of variously prepared laccase layers reveals that the parallel orientation of beta-sheet moieties results in high enzyme activity

  14. Low temperature hydrogen plasma-assisted atomic layer deposition of copper studied using in situ infrared reflection absorption spectroscopy

    International Nuclear Information System (INIS)

    Chaukulkar, Rohan P.; Rai, Vikrant R.; Agarwal, Sumit; Thissen, Nick F. W.

    2014-01-01

    Atomic layer deposition (ALD) is an ideal technique to deposit ultrathin, conformal, and continuous metal thin films. However, compared to the ALD of binary materials such as metal oxides and metal nitrides, the surface reaction mechanisms during metal ALD are not well understood. In this study, the authors have designed and implemented an in situ reflection-absorption infrared spectroscopy (IRAS) setup to study the surface reactions during the ALD of Cu on Al 2 O 3 using Cu hexafluoroacetylacetonate [Cu(hfac) 2 ] and a remote H 2 plasma. Our infrared data show that complete ligand-exchange reactions occur at a substrate temperature of 80 °C in the absence of surface hydroxyl groups. Based on infrared data and previous studies, the authors propose that Cu(hfac) 2 dissociatively chemisorbs on the Al 2 O 3 surface, where the Al-O-Al bridge acts as the surface reactive site, leading to surface O-Cu-hfac and O-Al-hfac species. Surface saturation during the Cu(hfac) 2 half-cycle occurs through blocking of the available chemisorption sites. In the next half-reaction cycle, H radicals from an H 2 plasma completely remove these surface hfac ligands. Through this study, the authors have demonstrated the capability of in situ IRAS as a tool to study surface reactions during ALD of metals. While transmission and internal reflection infrared spectroscopy are limited to the first few ALD cycles, IRAS can be used to probe all stages of metal ALD starting from initial nucleation to the formation of a continuous film

  15. Attenuated Total Reflection Mid-Infrared (ATR-MIR) Spectroscopy and Chemometrics for the Identification and Classification of Commercial Tannins.

    Science.gov (United States)

    Ricci, Arianna; Parpinello, Giuseppina P; Olejar, Kenneth J; Kilmartin, Paul A; Versari, Andrea

    2015-11-01

    Attenuated total reflection Fourier transform infrared (FT-IR) spectroscopy was used to characterize 40 commercial tannins, including condensed and hydrolyzable chemical classes, provided as powder extracts from suppliers. Spectral data were processed to detect typical molecular vibrations of tannins bearing different chemical groups and of varying botanical origin (univariate qualitative analysis). The mid-infrared region between 4000 and 520 cm(-1) was analyzed, with a particular emphasis on the vibrational modes in the fingerprint region (1800-520 cm(-1)), which provide detailed information about skeletal structures and specific substituents. The region 1800-1500 cm(-1) contained signals due to hydrolyzable structures, while bands due to condensed tannins appeared at 1300-900 cm(-1) and exhibited specific hydroxylation patterns useful to elucidate the structure of the flavonoid monomeric units. The spectra were investigated further using principal component analysis for discriminative purposes, to enhance the ability of infrared spectroscopy in the classification and quality control of commercial dried extracts and to enhance their industrial exploitation.

  16. Carbon dioxide adsorption on a ZnO(101[combining macron]0) substrate studied by infrared reflection absorption spectroscopy.

    Science.gov (United States)

    Buchholz, Maria; Weidler, Peter G; Bebensee, Fabian; Nefedov, Alexei; Wöll, Christof

    2014-01-28

    The adsorption of carbon dioxide on the mixed-terminated ZnO(101[combining macron]0) surface of a bulk single crystal was studied by UHV Infrared Reflection Absorption Spectroscopy (IRRAS). In contrast to metals, the classic surface selection rule for IRRAS does not apply to bulk oxide crystals, and hence vibrational bands can also be observed for s-polarized light. Although this fact substantially complicates data interpretation, a careful analysis allows for a direct determination of the adsorbate geometry. Here, we demonstrate the huge potential of IR-spectroscopy for investigations on oxide single crystal surfaces by considering all three components of the incident polarized light separately. We find that the tridentate (surface) carbonate is aligned along the [0001] direction. A comparison to data reported previously for CO2 adsorbed on the surfaces of ZnO nanoparticles provides important insight into the role of defects in the surface chemistry of powder particles.

  17. Direct determination of lycopene content in tomatoes (Lycopersicon esculentum) by attenuated total reflectance infrared spectroscopy and multivariate analysis.

    Science.gov (United States)

    Halim, Yuwana; Schwartz, Steven J; Francis, David; Baldauf, Nathan A; Rodriguez-Saona, Luis E

    2006-01-01

    Lycopene is a potent antioxidant that has been shown to play critical roles in disease prevention. Efficient assays for detection and quantification of lycopene are desirable as alternatives to time- and labor-intensive methods. Attenuated total reflectance infrared (ATR-IR) spectroscopy was used for quantification of lycopene in tomato varieties. Calibration models were developed by partial least-squares regression (PLSR) using quantitative measures of lycopene concentration from liquid chromatography as reference method. IR spectra showed a distinct marker band at 957 cm(-1) for trans Carbon-Hydrogen (CH) deformation vibration of lycopene. PLSR models predicted the lycopene content accurately and reproducibly with a correlation coefficient (sigma) of 0.96 and standard error of cross-validation ATR-IR spectroscopy allowed for rapid, simple, and accurate determination of lycopene in tomatoes with minimal sample preparation. Results suggest that the ATR-IR method is applicable for high-throughput quantitative analysis and screening for lycopene in tomatoes.

  18. Infrared reflection absorption spectroscopy study of radiation-heterogeneous processes in the system of aluminum-hexane

    International Nuclear Information System (INIS)

    Gadzhieva, N.N.; Rimikhanova, A.N.; Garibov, A.A.

    2004-01-01

    Full text: Infrared reflection absorption spectroscopy (IRRAS) was applied to study the regularities of radiation conversion of hexane on the surface of aluminum. The research object was the thin polished aluminum plate by mark of AD-00 with reflection coefficient R=0.8†0.85 in infrared range λ=2.2†15 μ . As adsorbate unsaturated vapors of spectroscopy clear hexane were used. The absorption of hexane (C 2 H 14 ) was being studied manometric at pressures P=(0.1†1.0)·10 2 Pa , what corresponded to monolayer value of 1-10. The samples were irradiated with γ-quanta of 60 Co with D=1.03 Gy·s -1 doze rate. Infrared reflection spectrum when linear-polarized radiation fall on the sample under angle ψ=10 o was measured by spectrophotometer 'Specord 71 JR' in diapason of 4000-650cm -1 at the temperature by mean of special reflecting arrangements. Formation of molecular hydrogen (H 2 ) and other gaseous products of decomposition were controlled by chromotographical and infrared spectroscopical methods. The analysis of hexane infrared absorption spectra after radiation-stimulated adsorption on the surface of aluminum, points out the formation of H-bonded hydrocarbon complex ( ν∼2680cm -1 ) with much loosening of C-H bond (the molecular form of absorption) and the possibility of proceeding dissociative absorption with formation of metal-alkyls (ν∼2880, 2920, 2970 cm -1 ). Probability of the last mentioned process, which proceeds in the most defective centers, increases with increasing of γ-radiation doze. It was established that the radiation processes in hetero system Al-ads.C 6 H 14 accelerate the radiolysis of hexane. At all these the radiation decomposition of hexane in hetero system Al-ads.C 6 H 14 is accompanied by formation the surface hydrides (ν∼1700-2000 cm -1 ), acetylene (ν∼3200-3300 cm -1 ), ethylene (ν∼980 cm -1 ), and also gaseous products of molecular hydrogen decomposition (H 2 ) and hydrocarbons C 1 -C 5 (bands with maxima 770, 790

  19. Early detection of melanoma with the combined use of acoustic microscopy, infrared reflectance and Raman spectroscopy

    Science.gov (United States)

    Karagiannis, Georgios T.; Grivas, Ioannis; Tsingotjidou, Anastasia; Apostolidis, Georgios K.; Grigoriadou, Ifigeneia; Dori, I.; Poulatsidou, Kyriaki-Nefeli; Doumas, Argyrios; Wesarg, Stefan; Georgoulias, Panagiotis

    2015-03-01

    Malignant melanoma is a form of skin cancer, with increasing incidence worldwide. Early diagnosis is crucial for the prognosis and treatment of the disease. The objective of this study is to develop a novel animal model of melanoma and apply a combination of the non-invasive imaging techniques acoustic microscopy, infrared (IR) and Raman spectroscopies, for the detection of developing tumors. Acoustic microscopy provides information about the 3D structure of the tumor, whereas, both spectroscopic modalities give qualitative insight of biochemical changes during melanoma development. In order to efficiently set up the final devices, propagation of ultrasonic and electromagnetic waves in normal skin and melanoma simulated structures was performed. Synthetic and grape-extracted melanin (simulated tumors), endermally injected, were scanned and compared to normal skin. For both cases acoustic microscopy with central operating frequencies of 110MHz and 175MHz were used, resulting to the tomographic imaging of the simulated tumor, while with the spectroscopic modalities IR and Raman differences among spectra of normal and melanin- injected sites were identified in skin depth. Subsequently, growth of actual tumors in an animal melanoma model, with the use of human malignant melanoma cells was achieved. Acoustic microscopy and IR and Raman spectroscopies were also applied. The development of tumors at different time points was displayed using acoustic microscopy. Moreover, the changes of the IR and Raman spectra were studied between the melanoma tumors and adjacent healthy skin. The most significant changes between healthy skin and the melanoma area were observed in the range of 900-1800cm-1 and 350-2000cm-1, respectively.

  20. Characterizing and Authenticating Montilla-Moriles PDO Vinegars Using Near Infrared Reflectance Spectroscopy (NIRS Technology

    Directory of Open Access Journals (Sweden)

    María-José De la Haba

    2014-02-01

    Full Text Available This study assessed the potential of near infrared (NIR spectroscopy as a non-destructive method for characterizing Protected Designation of Origin (PDO “Vinagres de Montilla-Moriles” wine vinegars and for classifying them as a function of the manufacturing process used. Three spectrophotometers were evaluated for this purpose: two monochromator instruments (Foss NIRSystems 6500 SY-I and Foss NIRSystems 6500 SY-II; spectral range 400–2,500 nm in both cases and a diode-array instrument (Corona 45 VIS/NIR; spectral range 380–1,700 nm. A total of 70 samples were used to predict major chemical quality parameters (total acidity, fixed acidity, volatile acidity, pH, dry extract, ash, acetoin, methanol, total polyphenols, color (tonality and intensity, and alcohol content, and to construct models for the classification of vinegars as a function of the manufacturing method used. The results obtained indicate that this non-invasive technology can be used successfully by the vinegar industry and by PDO regulators for the routine analysis of vinegars in order to authenticate them and to detect potential fraud. Slightly better results were achieved with the two monochromator instruments. The findings also highlight the potential of these NIR instruments for predicting the manufacturing process used, this being of particular value for the industrial authentication of traditional wine vinegars.

  1. Determination of oxygen content and carbonate impurity in YBa2Cu3O7-x by diffuse reflectance infrared spectroscopy

    International Nuclear Information System (INIS)

    Merzbacher, C.I.; Bonner, B.P.

    1991-01-01

    Samples of YBa 2 Cu 3 O 7-x with x ranging from ∼0 to 0.65 have been analyzed by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) in the midinfrared region (400--6000 cm -1 ). Spectral line shapes vary gradually as a function of oxygen stoichiometry, and the reflectance at 400 and 1000 cm -1 decreases linearly with decreasing oxygen content. Spectra of samples that were incompletely synthesized or exposed to a 4% CO 2 atmosphere at 650 degree C clearly indicated the presence of carbonate. DRIFTS is therefore a quick, nondestructive method for determining oxygen content in YBa 2 Cu 3 O 7-x powders, and for detecting carbonate species due to synthesis error or reaction with CO 2 -bearing atmosphere

  2. Analysis of Leucaena mimosine, Acacia tannins and total phenols by near infrared reflectance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, M N.V. [Hyderabad Univ. (India). Dept. of Plant Sciences

    1995-11-01

    The mimosine contents of Leucaena foliage, Acacia tannins and total phenols from leaf, bark and pod were analyzed by a near infrared relectance spectrophotometer (Compscan 3000). A calibration equation (linear summation regression) was developed with near infrared spectral analysis software, using 30 spectra from old and young leaves of Leucaena and 23 spectra from different samples of Acacia. The near infrared analyzer calculated that the percentages of mimosine, total phenols and tannins are closely comparable to laboratory results. (author)

  3. Preliminary evaluation of optical glucose sensing in red cell concentrations using near-infrared diffuse-reflectance spectroscopy

    Science.gov (United States)

    Suzuki, Yusuke; Maruo, Katsuhiko; Zhang, Alice W.; Shimogaki, Kazushige; Ogawa, Hideto; Hirayama, Fumiya

    2012-01-01

    Bacterial contamination of blood products is one of the most frequent infectious complications of transfusion. Since glucose levels in blood supplies decrease as bacteria proliferate, it should be possible to detect the presence of bacterial contamination by measuring the glucose concentrations in the blood components. Hence this study is aimed to serve as a preliminary study for the nondestructive measurement of glucose level in transfusion blood. The glucose concentrations in red blood cell (RBC) samples were predicted using near-infrared diffuse-reflectance spectroscopy in the 1350 to 1850 nm wavelength region. Furthermore, the effects of donor, hematocrit level, and temperature variations among the RBC samples were observed. Results showed that the prediction performance of a dataset which contained samples that differed in all three parameters had a standard error of 29.3 mg/dL. Multiplicative scatter correction (MSC) preprocessing method was also found to be effective in minimizing the variations in scattering patterns created by various sample properties. The results suggest that the diffuse-reflectance spectroscopy may provide another avenue for the detection of bacterial contamination in red cell concentrations (RCC) products.

  4. Non-destructive evaluation of degradation in EB-PVD thermal barrier coatings by infrared reflectance spectroscopy

    International Nuclear Information System (INIS)

    Flattum, Richard Y.; Cooney, Adam T.

    2013-01-01

    At room temperature and atmospheric conditions infrared reflectance spectroscopy and X-ray diffraction were employed for the detection of the phase transformation and residual stress within thermal barrier coatings (TBC). The TBC's samples initially consisted of the porous ceramic topcoat deposited by electron beam plasma vapor deposition, a bond coat and a superalloy substrate. Reflectance spectroscopy scans were performed from 7497 cm −1 to 68 cm −1 to analysis the fingerprint region as well as the chemical bonding region. These regions should indicate if a detectable change within the TBC response is a result of thermal degradation of the microstructure and the changes in yttrium dispersion throughout the yttrium stabilized zirconium. The thermal degradation was induced by thermal cycling the samples to 1100° C and then cooling them in an atmospheric environment. X-ray diffraction was also used to detect the phase composition within the TBC samples and see if either would clearly identify failure prior to actual spallation. The eventual measurability and quantify-ability of the phase changes within the TBC's may be used as an effective non-destructive evaluation (NDE) technique that would allow personnel in the field to know when servicing of the turbine blade was necessary.

  5. Application of attenuated total reflectance Fourier transform infrared spectroscopy for determination of cefixime in oral pharmaceutical formulations.

    Science.gov (United States)

    Kandhro, Aftab A; Laghari, Abdul Hafeez; Mahesar, Sarfaraz A; Saleem, Rubina; Nelofar, Aisha; Khan, Salman Tariq; Sherazi, S T H

    2013-11-01

    A quick and reliable analytical method for the quantitative assessment of cefixime in orally administered pharmaceutical formulations is developed by using diamond cell attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy as an easy procedure for quality control laboratories. The standards for calibration were prepared in aqueous medium ranging from 350 to 6000mg/kg. The calibration model was developed based on partial least square (PLS) using finger print region of FT-IR spectrum in the range from 1485 to 887cm(-1). Excellent coefficient of determination (R(2)) was achieved as high as 0.99976 with root mean square error of 44.8 for calibration. The application of diamond cell (smart accessory) ATR FT-IR proves a reliable determination of cefixime in pharmaceutical formulations to assess the quality of the final product. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Differentiation of Body Fluid Stains on Fabrics Using External Reflection Fourier Transform Infrared Spectroscopy (FT-IR) and Chemometrics.

    Science.gov (United States)

    Zapata, Félix; de la Ossa, Ma Ángeles Fernández; García-Ruiz, Carmen

    2016-04-01

    Body fluids are evidence of great forensic interest due to the DNA extracted from them, which allows genetic identification of people. This study focuses on the discrimination among semen, vaginal fluid, and urine stains (main fluids in sexual crimes) placed on different colored cotton fabrics by external reflection Fourier transform infrared spectroscopy (FT-IR) combined with chemometrics. Semen-vaginal fluid mixtures and potential false positive substances commonly found in daily life such as soaps, milk, juices, and lotions were also studied. Results demonstrated that the IR spectral signature obtained for each body fluid allowed its identification and the correct classification of unknown stains by means of principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). Interestingly, results proved that these IR spectra did not show any bands due to the color of the fabric and no substance of those present in daily life which were analyzed, provided a false positive. © The Author(s) 2016.

  7. [Fast determination of contents of nutrients and stone powder in compound fertilizer using near infrared diffuse reflectance spectroscopy].

    Science.gov (United States)

    Guo, Zheng; Yuan, Hong-Fu; Zhang, Xian; Song, Chun-Feng; Li, Xiao-Yu; Xie, Jin-Chun

    2011-06-01

    In the present paper, a new approach to fast determination of contents of nutrients, including total nitrogen content (N), P2O5 content (P) and K2O content (K), and of stone powder content in compound fertilizer composed of urea, ammonium dihydrogen phosphate, potassium chloride and stone powder was proposed using near infrared diffuse reflectance spectroscopy. PLS models of N, P and stone powder content were built with the SEP values of 0.8, 0.8 and 1.4 respectively. The information on which stone powder content model was built is the spectrum of crystal water existing in stone powder. K content was calculated using other ingredientcontents by normalization principle with a SEP value of 1.5. Although the SEP values are a little larger than the reproducibility errors of the GB/T methods which are conventional methods, the new method can be accepted by situ quality control in the production process of compound fertilizer.

  8. Study of Surface Wettability Change of Unconsolidated Sand Using Diffuse Reflectance Infrared Fourier Transform Spectroscopy and Thermogravimetric Analysis.

    Science.gov (United States)

    Gómora-Herrera, Diana; Navarrete Bolaños, Juan; Lijanova, Irina V; Olivares-Xometl, Octavio; Likhanova, Natalya V

    2018-04-01

    The effects exerted by the adsorption of vapors of a non-polar compound (deuterated benzene) and a polar compound (water) on the surface of Ottawa sand and a sample of reservoir sand (Channel), which was previously impregnated with silicon oil or two kinds of surfactants, (2-hydroxyethyl) trimethylammonium oleate (HETAO) and (2-hydroxyethyl)trimethylammonium azelate (HETAA), were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and thermogravimetric analysis (TGA). The surface chemistry of the sandstone rocks was elucidated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX). Terminal surface groups such as hydroxyls can strongly adsorb molecules that interact with these surface groups (surfactants), resulting in a wettability change. The wettability change effect suffered by the surface after treating it with surfactants was possible to be detected by the DRIFTS technique, wherein it was observed that the surface became more hydrophobic after being treated with silicon oil and HETAO; the surface became more hydrophilic after treating it with HETAA.

  9. The application of Near Infrared Reflectance Spectroscopy (NIRS for the quantitative analysis of hydrocortisone in primary materials

    Directory of Open Access Journals (Sweden)

    A. PITTAS

    2001-03-01

    Full Text Available Near Infrared Reflectance Spectroscopy (NIRS, coupled with fiber optic probes, has been shown to be a quick and reliable analytical tool for quality assurance and quality control in the pharmaceutical industry, both for verifications of raw materials and quantification of the active ingredients in final products. In this paper, a typical pharmaceutical product, hydrocortisone sodium succinate, is used as an example for the application of NIR spectroscopy for quality control. In order to develop an NIRS method with higher precision and accuracy than the official UV/VIS spectroscopic method (BP '99, 19 samples, taken from one year’s production and several prepared in the laboratory, having a hydrocortisone sodium succinate concentration in the range from 89.05%to 95.83 %, were analysed by NIR and UV/VIS spectroscopy. Three frequency ranges: 5939.73–5627.32 cm-1; 4863.64 – 4574.36 cm-1; 4308.23–4200.24 cm-1, with the best positive correlation between the changes in the spectral and concentration data, were chosen. The validity of the developed NIRS chemometric method for the determination of the hydrocortisone sodium succinate concentration, constructed by the partial least squares (PLS regression technique, is discussed. A correlation coefficient of 0.9758 and a standard error of cross validation (RMSECVof 1.06%were found between the UV/VI Sand òhe NIR spectroscopic results of the hydrocortisone sodium succinate concentration in the samples.

  10. Discrimination of the hard keratins animal horn and chelonian shell using attenuated total reflection-infrared spectroscopy.

    Science.gov (United States)

    Biscardi, Brianna; Welsh, Wendy; Kennedy, Anthony

    2012-05-01

    The ability to discriminate between objects manufactured from animal horn and chelonian (turtle, tortoise, or terrapin) shell is important from a cultural and archeological perspective such that it may allow conservators to determine the appropriate treatment and long-term care solution. It would also aid curators in identifying and cataloging items manufactured from these materials. Discrimination and classification is also a valuable tool for those involved in tracking the illegal trade in restricted materials of this nature. Attenuated total reflection infrared (ATR-IR) spectroscopy, using a single reflection diamond internal reflection element (IRE), coupled with discrimination analysis was used to analyze a total of thirty-nine samples (29 calibration samples, 10 validation samples). A discrimination analysis model was constructed using Mahalanobis distances to classify spectra into one of two classes. The model was then subsequently used to successfully classify all validation samples and correctly identify them as animal horn or chelonian shell based on second-derivative spectra of the amide I and II regions. This technique requires minimal to no sample preparation and may be used to nondestructively identify very small samples successfully without performing detailed secondary structural curve-fitting routines. This model should be a valuable resource to museums, conservators, and wildlife management programs for rapidly and reliably discriminating between animal horn and chelonian shell.

  11. Modeling and Forecasting of Depletion of Additives in Car Engine Oils Using Attenuated Total Reflectance Fast Transform Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Ronald Nguele

    2014-11-01

    Full Text Available On average, additives make up to 7% of a typical lubricant base. Commonly, they are blended with lube oils to enhance specific features thereby improving their qualities. Ultimately, additives participate in the performance of car engine oils. Using an analytical tool, attenuated total reflectance fast transform infrared spectroscopy, various grades of car engine oils, at different mileages, were analyzed. Sulfate oxidation and wear were found to trigger chemical processes which, in the long run, cause lubricant degradation while carbonyl oxidation was observed to occur only at a slow rate. Based upon data obtained from infrared spectra and using a curve fitting technique, mathematical equations predicting the theoretical rates of chemical change due to the aforementioned processes were examined. Additive depletions were found to obey exponential regression rather than polynomial. Moreover, breakpoint (breakpoint is used here to denote the initiation of deterioration of additives and critical mileage (critical mileage defines the distance at which the lubricant is chemically unusable of both samples were determined.

  12. Noninvasive observation of skeletal muscle contraction using near-infrared time-resolved reflectance and diffusing-wave spectroscopy

    Science.gov (United States)

    Belau, Markus; Ninck, Markus; Hering, Gernot; Spinelli, Lorenzo; Contini, Davide; Torricelli, Alessandro; Gisler, Thomas

    2010-09-01

    We introduce a method for noninvasively measuring muscle contraction in vivo, based on near-infrared diffusing-wave spectroscopy (DWS). The method exploits the information about time-dependent shear motions within the contracting muscle that are contained in the temporal autocorrelation function g(1)(τ,t) of the multiply scattered light field measured as a function of lag time, τ, and time after stimulus, t. The analysis of g(1)(τ,t) measured on the human M. biceps brachii during repetitive electrical stimulation, using optical properties measured with time-resolved reflectance spectroscopy, shows that the tissue dynamics giving rise to the speckle fluctuations can be described by a combination of diffusion and shearing. The evolution of the tissue Cauchy strain e(t) shows a strong correlation with the force, indicating that a significant part of the shear observed with DWS is due to muscle contraction. The evolution of the DWS decay time shows quantitative differences between the M. biceps brachii and the M. gastrocnemius, suggesting that DWS allows to discriminate contraction of fast- and slow-twitch muscle fibers.

  13. Application of multibounce attenuated total reflectance fourier transform infrared spectroscopy and chemometrics for determination of aspartame in soft drinks.

    Science.gov (United States)

    Khurana, Harpreet Kaur; Cho, Il Kyu; Shim, Jae Yong; Li, Qing X; Jun, Soojin

    2008-02-13

    Aspartame is a low-calorie sweetener commonly used in soft drinks; however, the maximum usage dose is limited by the U.S. Food and Drug Administration. Fourier transform infrared (FTIR) spectroscopy with attenuated total reflectance sampling accessory and partial least-squares regression (PLS) was used for rapid determination of aspartame in soft drinks. On the basis of spectral characterization, the highest R2 value, and lowest PRESS value, the spectral region between 1600 and 1900 cm(-1) was selected for quantitative estimation of aspartame. The potential of FTIR spectroscopy for aspartame quantification was examined and validated by the conventional HPLC method. Using the FTIR method, aspartame contents in four selected carbonated diet soft drinks were found to average from 0.43 to 0.50 mg/mL with prediction errors ranging from 2.4 to 5.7% when compared with HPLC measurements. The developed method also showed a high degree of accuracy because real samples were used for calibration, thus minimizing potential interference errors. The FTIR method developed can be suitably used for routine quality control analysis of aspartame in the beverage-manufacturing sector.

  14. Prediction of water content in game trophies by near infrared reflectance spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Kamler, Jiří; Dvořák, J.

    2007-01-01

    Roč. 15, č. 6 (2007), s. 401-404 ISSN 0967-0335 R&D Projects: GA ČR GP206/03/P134 Institutional research plan: CEZ:AV0Z60930519 Keywords : bone * NIR spectroscopy * roe deer * moisture Subject RIV: GK - Forestry Impact factor: 1.218, year: 2007

  15. Micro transflection on a metallic stick: an innovative approach of reflection infrared spectroscopy for minimally invasive investigation of painting varnishes.

    Science.gov (United States)

    Rosi, Francesca; Legan, Lea; Miliani, Costanza; Ropret, Polonca

    2017-05-01

    A new analytical approach, based on micro-transflection measurements from a diamond-coated metal sampling stick, is presented for the analysis of painting varnishes. Minimally invasive sampling is performed from the varnished surface using the stick, which is directly used as a transflection substrate for micro Fourier transform infrared (FTIR) measurements. With use of a series of varnished model paints, the micro-transflection method has been proved to be a valuable tool for the identification of surface components thanks to the selectivity of the sampling, the enhancement of the absorbance signal, and the easier spectral interpretation because the profiles are similar to transmission mode ones. Driven by these positive outcomes, the method was then tested as tool supporting noninvasive reflection FTIR spectroscopy during the assessment of varnish removal by solvent cleaning on paint models. Finally, the integrated analytical approach based on the two reflection methods was successfully applied for the monitoring of the cleaning of the sixteenth century painting Presentation in the Temple by Vittore Carpaccio. Graphical Abstract Micro-transflection FTIR on a metallic stick for the identification of varnishes during painting cleanings.

  16. Near-infrared reflectance spectroscopy for predicting amino acids content in intact processed animal proteins.

    Science.gov (United States)

    De la Haba, Maria José; Garrido-Varo, Ana; Guerrero-Ginel, José Emilio; Pérez-Marín, Dolores C

    2006-10-04

    Near-infrared calibrations were developed for the instantaneous prediction of amino acids composition of processed animal proteins (PAPs). Two sample presentation modes were compared (ground vs intact) for demonstrating the viability of the analysis in the intact form, avoiding the need for milling. Modified partial least-squares (MPLS) equations for the prediction of amino acids in PAPs were developed using the same set of samples (N = 92 PAPs) analyzed in ground and intact form and in three cups differing in the optical window size. The standard error for cross validation (SECV) and the coefficient of determination (1-VR) values yielded with the calibrations developed using the samples analyzed in the intact form showed similar or even better accuracy than those obtained with finely ground samples. The excellent predictive ability (1-VR > 0.90; CV marketing of these important protein feed ingredients, alleviating the costs and time associated with the routine quality controls.

  17. Diffuse Reflectance Spectroscopy of Hidden Objects, Part I: Interpretation of the Reflection-Absorption-Scattering Fractions in Near-Infrared (NIR) Spectra of Polyethylene Films.

    Science.gov (United States)

    Pomerantsev, Alexey L; Rodionova, Oxana Ye; Skvortsov, Alexej N

    2017-08-01

    Investigation of a sample covered by an interfering layer is required in many fields, e.g., for process control, biochemical analysis, and many other applications. This study is based on the analysis of spectra collected by near-infrared (NIR) diffuse reflectance spectroscopy. Each spectrum is a composition of a useful, target spectrum and a spectrum of an interfering layer. To recover the target spectrum, we suggest using a new phenomenological approach, which employs the multivariate curve resolution (MCR) method. In general terms, the problem is very complex. We start with a specific problem of analyzing a system, which consists of several layers of polyethylene (PE) film and underlayer samples with known spectral properties. To separate information originating from PE layers and the target, we modify the system versus both the number of the PE layers as well as the reflectance properties of the target sample. We consider that the interfering spectrum of the layer can be modeled using three components, which can be tentatively called transmission, absorption, and scattering contributions. The novelty of our approach is that we do not remove the reflectance and scattering effects from the spectra, but study them in detail aiming to use this information to recover the target spectrum.

  18. Ultrafast infrared vibrational spectroscopy

    CERN Document Server

    Fayer, Michael D

    2013-01-01

    The past ten years or so have seen the introduction of multidimensional methods into infrared and optical spectroscopy. The technology of multidimensional spectroscopy is developing rapidly and its applications are spreading to biology and materials science. Edited by a recognized leader in the field and with contributions from top researchers, including experimentalists and theoreticians, this book presents the latest research methods and results and will serve as an excellent resource for other researchers.

  19. Enhanced Single Seed Trait Predictions in Soybean (Glycine max) and Robust Calibration Model Transfer with Near-Infrared Reflectance Spectroscopy.

    Science.gov (United States)

    Hacisalihoglu, Gokhan; Gustin, Jeffery L; Louisma, Jean; Armstrong, Paul; Peter, Gary F; Walker, Alejandro R; Settles, A Mark

    2016-02-10

    Single seed near-infrared reflectance (NIR) spectroscopy predicts soybean (Glycine max) seed quality traits of moisture, oil, and protein. We tested the accuracy of transferring calibrations between different single seed NIR analyzers of the same design by collecting NIR spectra and analytical trait data for globally diverse soybean germplasm. X-ray microcomputed tomography (μCT) was used to collect seed density and shape traits to enhance the number of soybean traits that can be predicted from single seed NIR. Partial least-squares (PLS) regression gave accurate predictive models for oil, weight, volume, protein, and maximal cross-sectional area of the seed. PLS models for width, length, and density were not predictive. Although principal component analysis (PCA) of the NIR spectra showed that black seed coat color had significant signal, excluding black seeds from the calibrations did not impact model accuracies. Calibrations for oil and protein developed in this study as well as earlier calibrations for a separate NIR analyzer of the same design were used to test the ability to transfer PLS regressions between platforms. PLS models built from data collected on one NIR analyzer had minimal differences in accuracy when applied to spectra collected from a sister device. Model transfer was more robust when spectra were trimmed from 910 to 1679 nm to 955-1635 nm due to divergence of edge wavelengths between the two devices. The ability to transfer calibrations between similar single seed NIR spectrometers facilitates broader adoption of this high-throughput, nondestructive, seed phenotyping technology.

  20. Feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS) to quantify iron-cyanide (Fe-CN) complexes in soil

    Science.gov (United States)

    Sut-Lohmann, Magdalena; Raab, Thomas

    2017-04-01

    Contaminated sites create a significant risk to human health, by poisoning drinking water, soil, air and as a consequence food. Continuous release of persistent iron-cyanide (Fe-CN) complexes from various industrial sources poses a high hazard to the environment and indicates the necessity to analyze considerable amount of samples. At the present time quantitative determination of Fe-CN concentration in soil usually requires a time consuming two step process: digestion of the sample (e.g., micro distillation system) and its analytical detection performed, e.g., by automated spectrophotometrical flow injection analysis (FIA). In order to determine the feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS) to quantify the Fe-CN complexes in soil matrix, 42 soil samples were collected (8 to 12.520 mg kg-1CN) indicating single symmetrical CN band in the range 2092 - 2084 cm-1. Partial least squares (PLS) calibration-validation model revealed IR response to CNtot exceeding 1268 mg kg-1 (limit of detection, LOD). Subsequently, leave-one-out cross-validation (LOO-CV) was performed on soil samples containing low CNtot (900 mg kg-1 resulted in LOD equal to 3494 mg kg-1. Our results indicate that spectroscopic data in combination with PLS statistics can efficiently be used to predict Fe-CN concentrations in soil. We conclude that the protocol applied in this study can strongly reduce the time and costs essential for the spatial and vertical screening of the site affected by complexed Fe-CN.

  1. Discrimination of Transgenic Rice Based on Near Infrared Reflectance Spectroscopy and Partial Least Squares Regression Discriminant Analysis

    Directory of Open Access Journals (Sweden)

    ZHANG Long

    2015-09-01

    Full Text Available Near infrared reflectance spectroscopy (NIRS, a non-destructive measurement technique, was combined with partial least squares regression discrimiant analysis (PLS-DA to discriminate the transgenic (TCTP and mi166 and wild type (Zhonghua 11 rice. Furthermore, rice lines transformed with protein gene (OsTCTP and regulation gene (Osmi166 were also discriminated by the NIRS method. The performances of PLS-DA in spectral ranges of 4 000–8 000 cm-1 and 4 000–10 000 cm-1 were compared to obtain the optimal spectral range. As a result, the transgenic and wild type rice were distinguished from each other in the range of 4 000–10 000 cm-1, and the correct classification rate was 100.0% in the validation test. The transgenic rice TCTP and mi166 were also distinguished from each other in the range of 4 000–10 000 cm-1, and the correct classification rate was also 100.0%. In conclusion, NIRS combined with PLS-DA can be used for the discrimination of transgenic rice.

  2. The application of Near-Infrared Reflectance Spectroscopy (NIRS) to detect melamine adulteration of soya bean meal.

    Science.gov (United States)

    Haughey, Simon A; Graham, Stewart F; Cancouët, Emmanuelle; Elliott, Christopher T

    2013-02-15

    Soya bean products are used widely in the animal feed industry as a protein based feed ingredient and have been found to be adulterated with melamine. This was highlighted in the Chinese scandal of 2008. Dehulled soya (GM and non-GM), soya hulls and toasted soya were contaminated with melamine and spectra were generated using Near Infrared Reflectance Spectroscopy (NIRS). By applying chemometrics to the spectral data, excellent calibration models and prediction statistics were obtained. The coefficients of determination (R(2)) were found to be 0.89-0.99 depending on the mathematical algorithm used, the data pre-processing applied and the sample type used. The corresponding values for the root mean square error of calibration and prediction were found to be 0.081-0.276% and 0.134-0.368%, respectively, again depending on the chemometric treatment applied to the data and sample type. In addition, adopting a qualitative approach with the spectral data and applying PCA, it was possible to discriminate between the four samples types and also, by generation of Cooman's plots, possible to distinguish between adulterated and non-adulterated samples. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Quantitative evaluation of multiple adulterants in roasted coffee by Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and chemometrics.

    Science.gov (United States)

    Reis, Nádia; Franca, Adriana S; Oliveira, Leandro S

    2013-10-15

    The current study presents an application of Diffuse Reflectance Infrared Fourier Transform Spectroscopy for detection and quantification of fraudulent addition of commonly employed adulterants (spent coffee grounds, coffee husks, roasted corn and roasted barley) to roasted and ground coffee. Roasted coffee samples were intentionally blended with the adulterants (pure and mixed), with total adulteration levels ranging from 1% to 66% w/w. Partial Least Squares Regression (PLS) was used to relate the processed spectra to the mass fraction of adulterants and the model obtained provided reliable predictions of adulterations at levels as low as 1% w/w. A robust methodology was implemented that included the detection of outliers. High correlation coefficients (0.99 for calibration; 0.98 for validation) coupled with low degrees of error (1.23% for calibration; 2.67% for validation) confirmed that DRIFTS can be a valuable analytical tool for detection and quantification of adulteration in ground, roasted coffee. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Right prefrontal activity reflects the ability to overcome sleepiness during working memory tasks: a functional near-infrared spectroscopy study.

    Directory of Open Access Journals (Sweden)

    Motoyasu Honma

    Full Text Available It has been speculated that humans have an inherent ability to overcome sleepiness that counteracts homeostatic sleep pressure. However, it remains unclear which cortical substrate activities are involved in the ability to overcome sleepiness during the execution of cognitive tasks. Here we sought to confirm that this ability to overcome sleepiness in task execution improves performance on cognitive tasks, showing activation of neural substrates in the frontal cortex, by using a modified n-back (2- and 0-back working memory task and functional near-infrared spectroscopy. The change in alertness was just correlated with performances on the 2-back task. Activity in the right prefrontal cortex changed depending on alertness changes on the 2- and 0-back tasks independently, which indicates that activity in this region clearly reflects the ability to overcome sleepiness; it may contribute to the function of providing sufficient activity to meet the task load demands. This study reveals characteristics of the ability to overcome sleepiness during the n-back working memory task which goes beyond the attention-control function traditionally proposed.

  5. Left Prefrontal Activity Reflects the Ability of Vicarious Fear Learning: A Functional Near-Infrared Spectroscopy Study

    Directory of Open Access Journals (Sweden)

    Qingguo Ma

    2013-01-01

    Full Text Available Fear could be acquired indirectly via social observation. However, it remains unclear which cortical substrate activities are involved in vicarious fear transmission. The present study was to examine empathy-related processes during fear learning by-proxy and to examine the activation of prefrontal cortex by using functional near-infrared spectroscopy. We simultaneously measured participants’ hemodynamic responses and skin conductance responses when they were exposed to a movie. In this movie, a demonstrator (i.e., another human being was receiving a classical fear conditioning. A neutral colored square paired with shocks (CSshock and another colored square paired with no shocks (CSno-shock were randomly presented in front of the demonstrator. Results showed that increased concentration of oxygenated hemoglobin in left prefrontal cortex was observed when participants watched a demonstrator seeing CSshock compared with that exposed to CSno-shock. In addition, enhanced skin conductance responses showing a demonstrator's aversive experience during learning object-fear association were observed. The present study suggests that left prefrontal cortex, which may reflect speculation of others’ mental state, is associated with social fear transmission.

  6. Left prefrontal activity reflects the ability of vicarious fear learning: a functional near-infrared spectroscopy study.

    Science.gov (United States)

    Ma, Qingguo; Huang, Yujing; Wang, Lei

    2013-01-01

    Fear could be acquired indirectly via social observation. However, it remains unclear which cortical substrate activities are involved in vicarious fear transmission. The present study was to examine empathy-related processes during fear learning by-proxy and to examine the activation of prefrontal cortex by using functional near-infrared spectroscopy. We simultaneously measured participants' hemodynamic responses and skin conductance responses when they were exposed to a movie. In this movie, a demonstrator (i.e., another human being) was receiving a classical fear conditioning. A neutral colored square paired with shocks (CS(shock)) and another colored square paired with no shocks (CS(no-shock)) were randomly presented in front of the demonstrator. Results showed that increased concentration of oxygenated hemoglobin in left prefrontal cortex was observed when participants watched a demonstrator seeing CS(shock) compared with that exposed to CS(no-shock). In addition, enhanced skin conductance responses showing a demonstrator's aversive experience during learning object-fear association were observed. The present study suggests that left prefrontal cortex, which may reflect speculation of others' mental state, is associated with social fear transmission.

  7. Determination of quality parameters of beers by the use of attenuated total reflectance-Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Llario, Rafael; Iñón, Fernando A; Garrigues, Salvador; de la Guardia, Miguel

    2006-04-15

    The estimation of important quality parameters of beers, such as original and real extracts and alcohol content, has been evaluated by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) using a partial least square (PLS) calibration approach. Two sample populations, one consisting of 24 samples and other of 21 samples, obtained from the Spanish market and covering different types of beer were used. The first set was used for building and validating the model, whereas the second, measured 6 months after, was used for evaluating its robustness. The spectral range and the size of the calibration set and its suitability for building the PLS model have been evaluated. Considering a calibration set comprised of 12 samples, selected via hierarchical cluster analysis, and a validation data set of 11 samples, the absolute mean difference (d(x-y)) and standard deviation of mean differences (s(x-y)) of the real extract, original extract and alcohol content were 0.009 and 0.069% (w/w), -0.021 and 0.20% (w/w) and -0.003 and 0.130% (v/v), respectively. The maximum error for the prediction of any of these three parameters for a new sample did not exceed 2.5%. These values were practically invariant for both tested data sets. The developed methodology favourably compares with the automatic reference methodology in terms of speed and reagent consumption and waste generation.

  8. In Situ Nondestructive Analysis of Kalanchoe pinnata Leaf Surface Structure by Polarization-Modulation Infrared Reflection-Absorption Spectroscopy.

    Science.gov (United States)

    Hama, Tetsuya; Kouchi, Akira; Watanabe, Naoki; Enami, Shinichi; Shimoaka, Takafumi; Hasegawa, Takeshi

    2017-12-14

    The outermost surface of the leaves of land plants is covered with a lipid membrane called the cuticle that protects against various stress factors. Probing the molecular-level structure of the intact cuticle is highly desirable for understanding its multifunctional properties. We report the in situ characterization of the surface structure of Kalanchoe pinnata leaves using polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS). Without sample pretreatment, PM-IRRAS measures the IR spectra of the leaf cuticle of a potted K. pinnata plant. The peak position of the CH 2 -related modes shows that the cuticular waxes on the leaf surface are mainly crystalline, and the alkyl chains are highly packed in an all-trans zigzag conformation. The surface selection rule of PM-IRRAS revealed the average orientation of the cuticular molecules, as indicated by the positive and negative signals of the IR peaks. This unique property of PM-IRRAS revealed that the alkyl chains of the waxes and the main chains of polysaccharides are oriented almost perpendicular to the leaf surface. The nondestructive, background-free, and environmental gas-free nature of PM-IRRAS allows the structure and chemistry of the leaf cuticle to be studied directly in its native environment.

  9. Rapid intra-operative diagnosis of kidney cancer by attenuated total reflection infrared spectroscopy of tissue smears.

    Science.gov (United States)

    Pucetaite, Milda; Velicka, Martynas; Urboniene, Vidita; Ceponkus, Justinas; Bandzeviciute, Rimante; Jankevicius, Feliksas; Zelvys, Arunas; Sablinskas, Valdas; Steiner, Gerald

    2018-01-09

    Herein, a technique to analyze air-dried kidney tissue impression smears by means of attenuated total reflection infrared (ATR-IR) spectroscopy is presented. Spectral tumor markers-absorption bands of glycogen-are identified in the ATR-IR spectra of the kidney tissue smear samples. Thin kidney tissue cryo-sections currently used for IR spectroscopic analysis lack such spectral markers as the sample preparation causes irreversible molecular changes in the tissue. In particular, freeze-thaw cycle results in degradation of the glycogen and reduction or complete dissolution of its content. Supervised spectral classification was applied to the recorded spectra of the smears and the test spectra were classified with a high accuracy of 92% for normal tissue and 94% for tumor tissue, respectively. For further development, we propose that combination of the method with optical fiber ATR probes could potentially be used for rapid real-time intra-operative tissue analysis without interfering with either the established protocols of pathological examination or the ordinary workflow of operating surgeon. Such approach could ensure easier transition of the method to clinical applications where it may complement the results of gold standard histopathology examination and aid in more precise resection of kidney tumors. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Fourier Transform Infrared Spectroscopy Part III. Applications.

    Science.gov (United States)

    Perkins, W. D.

    1987-01-01

    Discusses the use of the FT-IR spectrometer in analyses that were previously avoided. Examines some of the applications of this spectroscopy with aqueous solutions, circular internal reflection, samples with low transmission, diffuse reflectance, infrared emission, and the infrared microscope. (TW)

  11. Characterization of southern yellow pine bark layers by Attenuated Total Reflectance (ATR) and Fourier Transform Infrared (FT-IR) Spectroscopy

    Science.gov (United States)

    Thomas L. Eberhardt

    2009-01-01

    The outer bark (rhytidome) of the southern yellow pines is a complex structure comprised of alternating layers of obliterated phloem and periderm tissues, with the latter comprised of three layers, those being phellem, phellogen, and phelloderm. An attenuated total reflectance (ATR) sampling accessory, coupled with a Fourier transform infrared (FTIR) spectrometer,...

  12. Temperature dependence of the phonon structure in the high-temperature superconductor Bi2Sr2CaCu2O8 studied by infrared reflectance spectroscopy

    International Nuclear Information System (INIS)

    Kamaras, K.; Herr, S.L.; Porter, C.D.; Tanner, D.B.; Etemad, S.; Tarascon, J.

    1991-01-01

    We have investigated a ceramic sample of the high-temperature superconductor Bi 2 Sr 2 CaCu 2 O 8 (T c =85 K) by infrared and visible reflectance spectroscopy at several temperatures both below and above the superconducting transition. We find that the temperature variation in the vibrational region is associated with minima or antiresonance features of the optical conductivity, instead of maxima, indicating strong Fano-type electron-phonon interaction and implying that the phonon structure in the infrared is strongly affected by the ab-plane response

  13. A fecal near-infrared reflectance spectroscopy-aided methodology to determine goat dietary composition in a Mediterranean shrubland.

    Science.gov (United States)

    Glasser, T; Landau, S; Ungar, E D; Perevolotsky, A; Dvash, L; Muklada, H; Kababya, D; Walker, J W

    2008-06-01

    An ecologically sound approach to the problem of brush encroachment onto Israeli rangeland might be their utilization by goats, but better knowledge of the feeding selectivity and ability of goats to thrive in encroached areas is required to devise viable production systems. Direct observation of bites could provide precise and accurate estimates of diet selection, but construction of a sufficiently large database would require too much time. The present study describes the first attempt to construct fecal near-infrared reflectance spectroscopy (NIRS) calibrations of the botanical and nutritional composition of the diet, and of the total intake of free-ranging goats, based on reference values determined with bite-count procedures. Calibration of fecal NIRS was based on 43 observations encompassing 3 goat breeds and 4 periods (spring, summer, and fall of 2004, and spring of 2005). Each observation comprised 242 min of continuous recording of the species and bite-type category selected by a single animal, on each of 2 consecutive days. The mass and chemical quality of each species and bite-type category-a total of more than 200,000 bites-were determined by using the simulated bite technique. Associated feces were scanned in the 1,100- to 2,500-nm range with a reflectance monochromator. Fecal NIRS calibrations had reasonable precision for dietary percentages of the 3 main botanical components: herbaceous vegetation (as one category; R(2) = 0.85), Phillyrea latifolia (R(2) = 0.89), and tannin-rich Pistacia lentiscus (R(2) = 0.77), with SE of cross-validation (SECV) of 7.8, 6.3, and 5.6% of DM, respectively. The R(2) values for dietary percentages of CP, NDF, IVDMD, and polyethylene glycol-binding tannins were 0.93, 0.88, 0.91, and 0.74, respectively, with SECV values of 0.9, 2.1, 4.3, and 0.9% of DM, respectively. The R(2) values for intakes of herbaceous vegetation, P. latifolia, and P. lentiscus were 0.80, 0.75, and 0.65, with SECV values of 71, 64, and 46 g of DM

  14. Mid-infrared upconversion spectroscopy

    DEFF Research Database (Denmark)

    Tidemand-Lichtenberg, Peter; Dam, Jeppe Seidelin; Andersen, H. V.

    2016-01-01

    Mid-infrared (MIR) spectroscopy is emerging as an attractive alternative to near-infrared or visible spectroscopy. MIR spectroscopy offers a unique possibility to probe the fundamental absorption bands of a large number of gases as well as the vibrational spectra of complex molecules. In this paper...

  15. Hygrothermal degradation of (3-glycidoxypropyl)trimethoxysilane films studied by neutron and X-ray reflectivity and attenuated total reflection infrared spectroscopy

    International Nuclear Information System (INIS)

    Tallant, David Robert; Garcia, Manuel Joseph; Majewski, Jaroslaw; Kent, Michael Stuart; Yim, Hyun

    2005-01-01

    Thin films of organosilanes have great technological importance in the areas of adhesion promotion, durability, and corrosion resistance. However, it is well-known that water can degrade organosilane films, particularly at elevated temperatures. In this work, X-ray and neutron reflectivity (XR and NR) were combined with attenuated total reflection infrared (ATR-IR) spectroscopy to study the chemical and structural changes within thin films of (3-glycidoxypropyl)trimethoxysilane (GPS) after exposure for various periods of time to air saturated with either D 2 O or H 2 O at 80 C. For NR and XR, ultrathin (∼100 (angstrom)) films were prepared by spin-coating. Both D 2 O and H 2 O provide neutron scattering contrast with GPS. Variations in the neutron scattering length density (SLD) profiles (a function of mass density and atomic composition) with conditioning time were measured after drying the samples out and also swelled with H 2 O or D 2 O vapor at room temperature. For samples that were dried out prior to measurement, little or no change was observed for H 2 O conditioning up to 3.5 days, but large changes were observed after 30 days of conditioning. The range of conditioning time for this structural change was narrowed to between 4 and 10 days with XR. The SLD profiles indicated that the top portion of the GPS film was transformed into a thick low-density layer after conditioning, but the bottom portion showed little structural change. A previous NR study of as-prepared GPS films involving swelling with deuterated nitrobenzene showed that the central portion of the film has much lower cross-link density than the region nearest the substrate. The present data show that the central portion also swells to a much greater extent with water and hydrolyzes more rapidly. The chemical degradation mechanism was identified by IR as hydrolysis of siloxane bonds. For ATR-IR, GPS films were prepared by dip-coating, which resulted in a greater and more variable thickness than

  16. Detection and identification of multiple adulterants in plant food supplements using attenuated total reflectance-Infrared spectroscopy.

    Science.gov (United States)

    Deconinck, E; Aouadi, C; Bothy, J L; Courselle, P

    2018-04-15

    Due to the rising popularity of dietary supplements, especially plant food supplements, and alternative herbal medicines, a whole market developed and these products became freely available through internet. Though several searches revealed that at least a part of these products, especially the ones obtained from websites disclosing their physical identity, are aldulterated with pharmaceutical compounds. This causes a threat for public health, since these compounds are not declared and therefore adverse effects will not immediately be related to the product. The more the adulterants can interfere with other medicinal treatments. Since the present active pharmaceutical ingredients are not declared on the package and the products are sold as 100% natural or herbal in nature, it is very difficult for custom personnel to discriminate between products to be confiscated or not. Therefore easy to apply analytical approaches to discriminate between adulterated and non-adulterated products are necessary. This paper presents an approach based on infrared spectroscopy combined with attenuated total reflectance (ATR) and partial least squares- discriminant analysis (PLS-DA) to easily differentiate between adulterated and non- adulterated plant food supplements and to get a first idea of the nature of the adulterant present. The performance of PLS-DA models based on Mid-IR and NIR data were compared as well as models based on the combined data. Further three preprocessing strategies were compared. The best performance was obtained for a PLS-DA model using Mid-IR data with the second derivative as preprocessing method. This model showed a correct classification rate of 98.3% for an external test set. Also eight real samples were screened using the model and for seven of these samples a correct classification was obtained. Generally it could be concluded that the obtained model and the presented approach could be used at customs to discriminate between adulterated and non

  17. Cow-specific diet digestibility predictions based on near-infrared reflectance spectroscopy scans of faecal samples.

    Science.gov (United States)

    Mehtiö, T; Rinne, M; Nyholm, L; Mäntysaari, P; Sairanen, A; Mäntysaari, E A; Pitkänen, T; Lidauer, M H

    2016-04-01

    This study was designed to obtain information on prediction of diet digestibility from near-infrared reflectance spectroscopy (NIRS) scans of faecal spot samples from dairy cows at different stages of lactation and to develop a faecal sampling protocol. NIRS was used to predict diet organic matter digestibility (OMD) and indigestible neutral detergent fibre content (iNDF) from faecal samples, and dry matter digestibility (DMD) using iNDF in feed and faecal samples as an internal marker. Acid-insoluble ash (AIA) as an internal digestibility marker was used as a reference method to evaluate the reliability of NIRS predictions. Feed and composite faecal samples were collected from 44 cows at approximately 50, 150 and 250 days in milk (DIM). The estimated standard deviation for cow-specific organic matter digestibility analysed by AIA was 12.3 g/kg, which is small considering that the average was 724 g/kg. The phenotypic correlation between direct faecal OMD prediction by NIRS and OMD by AIA over the lactation was 0.51. The low repeatability and small variability estimates for direct OMD predictions by NIRS were not accurate enough to quantify small differences in OMD between cows. In contrast to OMD, the repeatability estimates for DMD by iNDF and especially for direct faecal iNDF predictions were 0.32 and 0.46, respectively, indicating that developing of NIRS predictions for cow-specific digestibility is possible. A data subset of 20 cows with daily individual faecal samples was used to develop an on-farm sampling protocol. Based on the assessment of correlations between individual sample combinations and composite samples as well as repeatability estimates for individual sample combinations, we found that collecting up to three individual samples yields a representative composite sample. Collection of samples from all the cows of a herd every third month might be a good choice, because it would yield a better accuracy. © 2015 Blackwell Verlag GmbH.

  18. Rapid determination of carbohydrates, ash, and extractives contents of straw using attenuated total reflectance fourier transform mid-infrared spectroscopy.

    Science.gov (United States)

    Tamaki, Yukihiro; Mazza, Giuseppe

    2011-06-22

    Analysis of the chemical components of lignocellulosic biomass is essential to understanding its potential for utilization. Mid-infrared spectroscopy and partial least-squares regression were used for rapid measurement of the carbohydrate (total glycans; glucan; xylan; galactan; arabinan; mannan), ash, and extractives content of triticale and wheat straws. Calibration models for total glycans, glucan, and extractives showed good and excellent predictive performance on the basis of slope, r², RPD, and R/SEP criteria. The xylan model showed good and acceptable predictive performance. However, the ash model was evaluated as providing only approximate quantification and screening. The models for galactan, arabinan, and mannan indicated poor and insufficient prediction for application. Most models could predict both triticale and wheat straw samples with the same degree of accuracy. Mid-infrared spectroscopic techniques coupled with partial least-squares regression can be used for rapid prediction of total glycans, glucan, xylan, and extractives in triticale and wheat straw samples.

  19. Near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Virendra Jain

    2015-01-01

    Full Text Available Tissue ischaemia can be a significant contributor to increased morbidity and mortality. Conventional oxygenation monitoring modalities measure systemic oxygenation, but regional tissue oxygenation is not monitored. Near-infrared spectroscopy (NIRS is a non-invasive monitor for measuring regional oxygen saturation which provides real-time information. There has been increased interest in the clinical application of NIRS following numerous studies that show improved outcome in various clinical situations especially cardiac surgery. Its use has shown improved neurological outcome and decreased postoperative stay in cardiac surgery. Its usefulness has been investigated in various high risk surgeries such as carotid endarterectomy, thoracic surgeries, paediatric population and has shown promising results. There is however, limited data supporting its role in neurosurgical population. We strongly feel, it might play a key role in future. It has significant advantages over other neuromonitoring modalities, but more technological advances are needed before it can be used more widely into clinical practice.

  20. Sensing cocaine in saliva with attenuated total reflection infrared (ATR-IR) spectroscopy combined with a one-step extraction method

    Science.gov (United States)

    Hans, Kerstin M.-C.; Gianella, Michele; Sigrist, Markus W.

    2012-03-01

    On-site drug tests have gained importance, e.g., for protecting the society from impaired drivers. Since today's drug tests are majorly only positive/negative, there is a great need for a reliable, portable and preferentially quantitative drug test. In the project IrSens we aim to bridge this gap with the development of an optical sensor platform based on infrared spectroscopy and focus on cocaine detection in saliva. We combine a one-step extraction method, a sample drying technique and infrared attenuated total reflection (ATR) spectroscopy. As a first step we have developed an extraction technique that allows us to extract cocaine from saliva to an almost infrared-transparent solvent and to record ATR spectra with a commercially available Fourier Transform-infrared spectrometer. To the best of our knowledge this is the first time that such a simple and easy-to-use one-step extraction method is used to transfer cocaine from saliva into an organic solvent and detect it quantitatively. With this new method we are able to reach a current limit of detection around 10 μg/ml. This new extraction method could also be applied to waste water monitoring and controlling caffeine content in beverages.

  1. Potential and limitation of mid-infrared attenuated total reflectance spectroscopy for real time analysis of raw milk in milking lines.

    Science.gov (United States)

    Linker, Raphael; Etzion, Yael

    2009-02-01

    Real-time information about milk composition would be very useful for managing the milking process. Mid-infrared spectroscopy, which relies on fundamental modes of molecular vibrations, is routinely used for off-line analysis of milk and the purpose of the present study was to investigate the potential of attenuated total reflectance mid-infrared spectroscopy for real-time analysis of milk in milking lines. The study was conducted with 189 samples from over 70 cows that were collected during an 18 months period. Principal component analysis, wavelets and neural networks were used to develop various models for predicting protein and fat concentration. Although reasonable protein models were obtained for some seasonal sub-datasets (determination errors protein), the models lacked robustness and it was not possible to develop a model suitable for all the data. Determination of fat concentration proved even more problematic and the determination errors remained unacceptably large regardless of the sub-dataset analyzed or of the spectral intervals used. These poor results can be explained by the limited penetration depth of the mid-infrared radiation that causes the spectra to be very sensitive to the presence of fat globules or fat biofilms in the boundary layer that forms at the interface between the milk and the crystal that serves both as radiation waveguide and sensing element. Since manipulations such as homogenisation are not permissible for in-line analysis, these results show that the potential of mid-infrared attenuated total reflectance spectroscopy for in-line milk analysis is indeed quite limited.

  2. Using mid-Infrared External Reflectance Spectroscopy to Distinguish Between Different Commercially Produced Poly[Methyl MethAcrylate] (PMMA) Samples - A Null Result

    Science.gov (United States)

    Fajardo, Mario; Neel, Christopher; Lacina, David

    2017-06-01

    We report (null) results of experiments testing the hypothesis that mid-infrared (mid-IR) spectroscopy can be used to distinguish samples of poly[methyl methacrylate] (PMMA) obtained from different commercial suppliers. This work was motivated by the desire for a simple non-destructive and non-invasive test for pre-sorting PMMA samples prior to use in shock and high-strain-rate experiments, where PMMA is commonly used as a standard material. We discuss: our choice of mid-IR external reflectance spectroscopy, our approach to recording reflectance spectra at near-normal (θ = 0 + / - 5 degree) incidence and for extracting the wavelength-weighted absorption spectrum from the raw reflectance data via a Kramers-Krönig analysis. We employ extensive signal, which necessitates adopting a special experimental protocol to mitigate the effects of instrumental drift. Finally, we report spectra of three PMMA samples with different commercial pedigrees, and show that they are virtually identical (+ / - 1 % error, 95% confidence); obviating the use of mid-IR reflectance spectroscopy to tell the samples apart.

  3. Measurement of sugar content of watermelon using near-infrared reflectance spectroscopy in comparison with dielectric property

    Science.gov (United States)

    Tao, Xuemei; Bao, Yidan

    2006-09-01

    The sugar content of watermelon is important to its taste thus influences the market. It's difficult to know whether the melon is sweet or not for consumers. We tried to develop a convenient meter to determine the sugar of watermelon. The first objective of this paper was to demonstrate the feasibility of using a near-infrared reflectance spectrometer (NIRS) to investigate the relationship between sugar content of watermelon and absorption spectra. The NIRS reflectance of nondestructive watermelon was measured with a Visible/NIR spectrophotometer in 325-1075nm range. The sugar content of watermelon was obtained with a handhold sugar content meter. The second objective was to measure the watermelon's dielectric property, such as dielectric resistance, capacitance, quality factor and dielectric loss. A digital electric bridge instrument was used to get the dielectric property. The experimental results show that they were related to watermelon's sugar content. A comparison between the two methods was made in the paper. The model derived from NIRS reflection is useful for class identification of Zaochun Hongyu watermelon though it's not quite accurate in sweetness prediction (the max. deviation is 0.7). Electric property bears little relation to sugar content of watermelon at this experiment and it couldn't be used as non-destructive inspection method.

  4. Fourier transform infrared-attenuated total reflectance (FTIR-ATR spectroscopy and chemometric techniques for the determination of adulteration in petrodiesel/biodiesel blends

    Directory of Open Access Journals (Sweden)

    Armando Guerrero Peña

    2014-06-01

    Full Text Available We propose an analytical method based on fourier transform infrared-attenuated total reflectance (FTIR-ATR spectroscopy to detect the adulteration of petrodiesel and petrodiesel/palm biodiesel blends with African crude palm oil. The infrared spectral fingerprints from the sample analysis were used to perform principal components analysis (PCA and to construct a prediction model using partial least squares (PLS regression. The PCA results separated the samples into three groups, allowing identification of those subjected to adulteration with palm oil. The obtained model shows a good predictive capacity for determining the concentration of palm oil in petrodiesel/biodiesel blends. Advantages of the proposed method include cost-effectiveness and speed; it is also environmentally friendly.

  5. Comparison of Attenuated Total Reflectance Mid-Infrared, Near Infrared, and 1H-Nuclear Magnetic Resonance Spectroscopies for the Determination of Coffee’s Geographical Origin

    Directory of Open Access Journals (Sweden)

    Jessica Medina

    2017-01-01

    Full Text Available The sensorial properties of Colombian coffee are renowned worldwide, which is reflected in its market value. This raises the threat of fraud by adulteration using coffee grains from other countries, thus creating a demand for robust and cost-effective methods for the determination of geographical origin of coffee samples. Spectroscopic techniques such as Nuclear Magnetic Resonance (NMR, near infrared (NIR, and mid-infrared (mIR have arisen as strong candidates for the task. Although a body of work exists that reports on their individual performances, a faithful comparison has not been established yet. We evaluated the performance of 1H-NMR, Attenuated Total Reflectance mIR (ATR-mIR, and NIR applied to fraud detection in Colombian coffee. For each technique, we built classification models for discrimination by species (C. arabica versus C. canephora (or robusta and by origin (Colombia versus other C. arabica using a common set of coffee samples. All techniques successfully discriminated samples by species, as expected. Regarding origin determination, ATR-mIR and 1H-NMR showed comparable capacity to discriminate Colombian coffee samples, while NIR fell short by comparison. In conclusion, ATR-mIR, a less common technique in the field of coffee adulteration and fraud detection, emerges as a strong candidate, faster and with lower cost compared to 1H-NMR and more discriminating compared to NIR.

  6. Semiconductor optoelectronic infrared spectroscopy

    International Nuclear Information System (INIS)

    Hollingworth, A.R.

    2001-08-01

    We use spectroscopy to study infrared optoelectronic inter and intraband semiconductor carrier dynamics. The overall aim of this thesis was to study both III-V and Pb chalcogenide material systems in order to show their future potential use in infrared emitters. The effects of bandstructure engineering have been studied in the output characteristics of mid-IR III-V laser diodes to show which processes (defects, radiative, Auger and phonon) dominate and whether non-radiative processes can be suppressed. A new three-beam pump probe experiment was used to investigate interband recombination directly in passive materials. Experiments on PbSe and theory for non-parabolic near-mirror bands and non-degenerate statistics were in good agreement. Comparisons with HgCdTe showed a reduction in the Auger coefficient of 1-2 orders of magnitude in the PbSe. Using Landau confinement to model spatial confinement in quantum dots (QDs) 'phonon bottlenecking' was studied. The results obtained from pump probe and cyclotron resonance saturation measurements showed a clear suppression in the cooling of carriers when Landau level separation was not resonant with LO phonon energy. When a bulk laser diode was placed in a magnetic field to produce a quasi quantum wire device the resulting enhanced differential gain and reduced Auger recombination lowered I th by 30%. This result showed many peaks in the light output which occurred when the LO phonon energy was a multiple of the Landau level separation. This showed for the first time evidence of the phonon bottleneck in a working laser device. A new technique called time resolved optically detected cyclotron resonance, was used as a precursor to finding the carrier dynamics within a spatially confined quantum dot. By moving to the case of a spatial QD using an optically detected intraband resonance it was possible to measure the energy separation interband levels and conduction and valence sublevels within the dot simultaneously. Furthermore

  7. Transient Infrared Emission Spectroscopy

    Science.gov (United States)

    Jones, Roger W.; McClelland, John F.

    1989-12-01

    Transient Infrared Emission Spectroscopy (TIRES) is a new technique that reduces the occurrence of self-absorption in optically thick solid samples so that analytically useful emission spectra may be observed. Conventional emission spectroscopy, in which the sample is held at an elevated, uniform temperature, is practical only for optically thin samples. In thick samples the emission from deep layers of the material is partially absorbed by overlying layers.1 This self-absorption results in emission spectra from most optically thick samples that closely resemble black-body spectra. The characteristic discrete emission bands are severely truncated and altered in shape. TIRES bypasses this difficulty by using a laser to heat only an optically thin surface layer. The increased temperature of the layer is transient since the layer will rapidly cool and thicken by thermal diffusion; hence the emission collection must be correlated with the laser heating. TIRES may be done with both pulsed and cw lasers.2,3 When a pulsed laser is used, the spectrometer sampling must be synchronized with the laser pulsing so that only emission during and immediately after each laser pulse is observed.3 If a cw laser is used, the sample must move rapidly through the beam. The hot, transient layer is then in the beam track on the sample at and immediately behind the beam position, so the spectrometer field of view must be limited to this region near the beam position.2 How much self-absorption the observed emission suffers depends on how thick the heated layer has grown by thermal diffusion when the spectrometer samples the emission. Use of a pulsed laser synchronized with the spectrometer sampling readily permits reduction of the time available for heat diffusion to about 100 acs .3 When a cw laser is used, the heat-diffusion time is controlled by how small the spectrometer field of view is and by how rapidly the sample moves past within this field. Both a very small field of view and a

  8. Analysis of ewe’s milk by FT Near Infrared spectroscopy: measurement of samples on Petri dishes in reflectance mode

    Directory of Open Access Journals (Sweden)

    Květoslava Šustová

    2006-01-01

    Full Text Available Our work deals with a possibility of determination of basic composition (dry matter, fat, protein, casein, lactose and urea nitrogen of ewe’s milk and colostrum by FT NIR spectroscopy. Samples of milk were warmed to 40 °C, agitated, cooled to 20 °C, transferred into Petri dishes and analysed by reference methods and by FT NIR in reflectance mode. The measured area was spaced by a metallic mirror. Statistically significant differences between the reference values and the calculated values of NIR were not found (p=0.05. Results of calibration for ewe’s milk determined the highest correlation coefficients: dry matter 0.983, fat 0.989, true protein 0.997, casein 0.977, lactose 0.980 and urea nitrogen 0.973. The study showed that NIRS method, when samples of milk are measured on Petri dishes, is a useful technique for the prediction of dry matter, fat, protein and casein in ewe’s milk.

  9. Infrared diode laser spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Civiš, Svatopluk; Cihelka, Jaroslav; Matulková, Irena

    2010-01-01

    Roč. 18, č. 4 (2010), s. 408-420 ISSN 1230-3402 R&D Projects: GA AV ČR IAA400400705 Institutional research plan: CEZ:AV0Z40400503 Keywords : FTIR spectroscopy * absorption spectroscopy * laser diodes Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.027, year: 2010

  10. Classification of pumpkin seed oils according to their species and genetic variety by attenuated total reflection Fourier-transform infrared spectroscopy.

    Science.gov (United States)

    Saucedo-Hernández, Yanelis; Lerma-García, María Jesús; Herrero-Martínez, José Manuel; Ramis-Ramos, Guillermo; Jorge-Rodríguez, Elisa; Simí-Alfonso, Ernesto F

    2011-04-27

    Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), followed by multivariate treatment of the spectral data, was used to classify seed oils of the genus Cucurbita (pumpkins) according to their species as C. maxima, C. pepo, and C. moschata. Also, C. moschata seed oils were classified according to their genetic variety as RG, Inivit C-88, and Inivit C-2000. Up to 23 wavelength regions were selected on the spectra, each region corresponding to a peak or shoulder. The normalized absorbance peak areas within these regions were used as predictors. Using linear discriminant analysis (LDA), an excellent resolution among all categories concerning both Cucurbita species and C. moschata varieties was achieved. The proposed method was straightforward and quick and can be easily implemented. Quality control of pumpkin seed oils is important because Cucurbita species and genetic variety are both related to the pharmaceutical properties of the oils.

  11. Gas sensing properties and in situ diffuse reflectance infrared Fourier transform spectroscopy study of trichloroethylene adsorption and reactions on SnO2 films

    Science.gov (United States)

    Zhang, Zhenxin; Huang, Kaijin; Yuan, Fangli; Xie, Changsheng

    2014-05-01

    The detection of trichloroethylene has attracted much attention because it has an important effect on human health. The sensitivity of the SnO2 flat-type coplanar gas sensor arrays to 100 ppm trichloroethylene in air was investigated. The adsorption and surface reactions of trichloroethylene were investigated at 100-200 °C by in-situ diffuse reflection Fourier transform infrared spectroscopy (DIRFTS) on SnO2 films. Molecularly adsorbed trichloroethylene, dichloroacetyl chloride (DCAC), phosgene, HCl, CO, H2O, CHCl3, Cl2 and CO2 surface species are formed during trichloroethylene adsorption at 100-200 °C. A possible mechanism of the reaction process is discussed.

  12. CO 2 Capture Capacity and Swelling Measurements of Liquid-like Nanoparticle Organic Hybrid Materials via Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy

    KAUST Repository

    Park, Youngjune

    2012-01-12

    Novel nanoparticle organic hybrid materials (NOHMs), which are comprised of organic oligomers or polymers tethered to an inorganic nanosized cores of various sizes, have been synthesized, and their solvating property for CO 2 was investigated using attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy. Simultaneous measurements of CO 2 capture capacity and swelling behaviors of polyetheramine (Jeffamine M-2070) and its corresponding NOHMs (NOHM-I-PE2070) were reported at temperatures of (298, 308, 323 and 353) K and CO 2 pressure conditions ranging from (0 to 5.5) MPa. The polymeric canopy, or polymer bound to the nanoparticle surface, showed significantly less swelling behavior with enhanced or comparable CO 2 capture capacity compared to pure unbound polyetheramine. © 2011 American Chemical Society.

  13. Investigation on H-containing shallow trap of hydrogenated TiO2 with in situ Fourier transform infrared diffuse reflection spectroscopy.

    Science.gov (United States)

    Han, Bing; Hang Hu, Yun

    2017-07-28

    A novel technique, high temperature high pressure in situ Fourier transform infrared diffuse reflection spectroscopy, was successfully used to investigate the formation and stability of shallow trap states in P25 TiO 2 nanoparticles. Two types of shallow traps (with and without H atoms) were identified. The H-containing shallow trap can be easily generated by heating in H 2 atmosphere. However, the trap is unstable in vacuum at 600 °C. In contrast, the H-free shallow trap, which can be formed by heating in vacuum, is stable even at 600 °C. The energy gaps between shallow trap states and the conduction band are 0.09 eV for H-containing shallow trap and 0.13 eV for H-free shallow trap, indicating that the H-containing shallow trap state is closer to the conduction band than that without H.

  14. A simple, sensitive and non-destructive technique for characterizing bovine dental enamel erosion: attenuated total reflection Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Kim, In-Hye; Son, Jun Sik; Min, Bong Ki; Kim, Young Kyoung; Kim, Kyo-Han; Kwon, Tae-Yub

    2016-03-30

    Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Deionized water (control) and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth (110) were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 °C. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers' microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ν1, ν3 phosphate contour: the ratio of the height amplitude of ν3 PO4 to that of ν1 PO4 (Method 1) and the shift of the ν3 PO4 peak to a higher wavenumber (Method 2). The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy (Perosion.

  15. Direct and simultaneous quantification of tannin mean degree of polymerization and percentage of galloylation in grape seeds using diffuse reflectance fourier transform-infrared spectroscopy.

    Science.gov (United States)

    Pappas, Christos; Kyraleou, Maria; Voskidi, Eleni; Kotseridis, Yorgos; Taranilis, Petros A; Kallithraka, Stamatina

    2015-02-01

    The direct and simultaneous quantitative determination of the mean degree of polymerization (mDP) and the degree of galloylation (%G) in grape seeds were quantified using diffuse reflectance infrared Fourier transform spectroscopy and partial least squares (PLS). The results were compared with those obtained using the conventional analysis employing phloroglucinolysis as pretreatment followed by high performance liquid chromatography-UV and mass spectrometry detection. Infrared spectra were recorded in solid state samples after freeze drying. The 2nd derivative of the 1832 to 1416 and 918 to 739 cm(-1) spectral regions for the quantification of mDP, the 2nd derivative of the 1813 to 607 cm(-1) spectral region for the degree of %G determination and PLS regression were used. The determination coefficients (R(2) ) of mDP and %G were 0.99 and 0.98, respectively. The corresponding values of the root-mean-square error of calibration were found 0.506 and 0.692, the root-mean-square error of cross validation 0.811 and 0.921, and the root-mean-square error of prediction 0.612 and 0.801. The proposed method in comparison with the conventional method is simpler, less time consuming, more economical, and requires reduced quantities of chemical reagents and fewer sample pretreatment steps. It could be a starting point for the design of more specific models according to the requirements of the wineries. © 2015 Institute of Food Technologists®

  16. The problem of 2,4,6-trichloroanisole in cork planks studied by attenuated total reflection infrared spectroscopy: proof of concept.

    Science.gov (United States)

    Garcia, Ana R; Lopes, Luís F; Brito de Barros, Ricardo; Ilharco, Laura M

    2015-01-14

    Attenuated total reflection infrared spectroscopy (ATR-IR) proved to be a promising detection technique for 2,4,6-trichloroanisole (TCA), which confers organoleptic defects to bottled alcoholic beverages, allowing the proposal of a criterion for cork plank acceptance when meant for stopper production. By analysis of a significant number of samples, it was proved that the presence of TCA, even in very low concentrations, imparts subtle changes to the cork spectra, namely, the growth of two new bands at ∼1417 (νC═C of TCA ring) and 1314 cm–1 (a shifted νCC of TCA) and an increase in the relative intensities of the bands at ∼1039 cm–1 (δCO of polysaccharides) and ∼813 cm–1 (τCH of suberin), the latter by overlapping with intense bands of TCA. These relative intensities were evaluated in comparison to a fingerprint of suberin (νasC–O–C), at 1161 cm–1. On the basis of those spectral variables, a multivariate statistics linear analysis (LDA) was performed to obtain a discriminant function that allows classifying the samples according to whether they contain or not TCA. The methodology proposed consists of a demanding acceptance criterion for cork planks destined for stopper production (with the guarantee of nonexistence of TCA) that results from combining the quantitative results with the absence of the two TCA correlated bands. ATR infrared spectroscopy is a nondestructive and easy to apply technique, both on cork planks and on stoppers, and has proven more restrictive than other techniques used in the cork industry that analyze the cleaning solutions. At the level of proof of concept, the method here proposed is appealing for high-value stopper applications.

  17. Photographic infrared spectroscopy and near infrared photometry of Be stars

    International Nuclear Information System (INIS)

    Swings, J.P.

    1976-01-01

    Two topics are tackled in this presentation: spectroscopy and photometry. The following definitions are chosen: photographic infrared spectroscopy (wavelengths Hα<=lambda<1.2 μ); near infrared photometry (wavebands: 1.6 μ<=lambda<=20 μ). Near infrared spectroscopy and photometry of classical and peculiar Be stars are discussed and some future developments in the field are outlined. (Auth.)

  18. High-resolution reflection spectroscopy

    International Nuclear Information System (INIS)

    Ducloy, Martial

    1997-01-01

    In this article some recent developments in selective reflection spectroscopy is reviewed and the various ways to extend Doppler free techniques to this spectroscopic field is discussed. Its main feature is to probe atomic gas close to the cell boundaries

  19. Stand-alone polarization-modulation infrared reflection absorption spectroscopy instrument optimized for the study of catalytic processes at elevated pressures

    Science.gov (United States)

    Kestell, John D.; Mudiyanselage, Kumudu; Ye, Xinyi; Nam, Chang-Yong; Stacchiola, Dario; Sadowski, Jerzy; Boscoboinik, J. Anibal

    2017-10-01

    This paper describes the design and construction of a compact, "user-friendly" polarization-modulation infrared reflection absorption spectroscopy (PM-IRRAS) instrument at the Center for Functional Nanomaterials (CFN) of Brookhaven National Laboratory, which allows studying surfaces at pressures ranging from ultra-high vacuum to 100 Torr. Surface infrared spectroscopy is ideally suited for studying these processes as the vibrational frequencies of the IR chromophores are sensitive to the nature of the bonding environment on the surface. Relying on the surface selection rules, by modulating the polarization of incident light, it is possible to separate the contributions from the isotropic gas or solution phase, from the surface bound species. A spectral frequency range between 1000 cm-1 and 4000 cm-1 can be acquired. While typical spectra with a good signal to noise ratio can be obtained at elevated pressures of gases in ˜2 min at 4 cm-1 resolution, we have also acquired higher resolution spectra at 0.25 cm-1 with longer acquisition times. By way of verification, CO uptake on a heavily oxidized Ru(0001) sample was studied. As part of this test study, the presence of CO adsorbed on Ru bridge sites was confirmed, in agreement with previous ambient pressure X ray photoelectron spectroscopy studies. In terms of instrument performance, it was also determined that the gas phase contribution from CO could be completely removed even up to pressures close to 100 Torr. A second test study demonstrated the use of the technique for studying morphological properties of a spin coated polymer on a conductive surface. Note that this is a novel application of this technique. In this experiment, the polarization of incident light was modulated manually (vs. through a photoelastic modulator). It was demonstrated, in good agreement with the literature, that the polymer chains preferentially lie parallel with the surface. This PM-IRRAS system is small, modular, and easily

  20. Influence of composition and roughness on the pigment mapping of paintings using mid-infrared fiberoptics reflectance spectroscopy (mid-IR FORS) and multivariate calibration.

    Science.gov (United States)

    Sessa, Clarimma; Bagán, Héctor; García, Jose Francisco

    2014-10-01

    Mid-infrared fiberoptics reflectance spectroscopy (mid-IR FORS) is a very interesting technique for artwork characterization purposes. However, the fact that the spectra obtained are a mixture of surface (specular) and volume (diffuse) reflection is a significant drawback. The physical and chemical features of the artwork surface may produce distortions in the spectra that hinder comparison with reference databases acquired in transmission mode. Several studies attempted to understand the influence of the different variables and propose procedures to improve the interpretation of the spectra. This article is focused on the application of mid-IR FORS and multivariate calibration to the analysis of easel paintings. The objectives are the evaluation of the influence of the surface roughness on the spectra, the influence of the matrix composition for the classification of unknown spectra, and the capability of obtaining pigment composition mappings. A first evaluation of a fast procedure for spectra management and pigment discrimination is discussed. The results demonstrate the capability of multivariate methods, principal component analysis (PCA), and partial least squares discrimination analysis (PLS-DA), to model the distortions of the reflectance spectra and to delimitate and discriminate areas of uniform composition. The roughness of the painting surface is found to be an important factor affecting the shape and relative intensity of the spectra. A mapping of the major pigments of a painting is possible using mid-IR FORS and PLS-DA when the calibration set is a palette that includes the potential pigments present in the artwork mixed with the appropriate binder and that shows the different paint textures.

  1. To See the World in a Grain of Sand: Recognizing the Origin of Sand Specimens by Diffuse Reflectance Infrared Fourier Transform Spectroscopy and Multivariate Exploratory Data Analysis

    Science.gov (United States)

    Pezzolo, Alessandra De Lorenzi

    2011-01-01

    The diffuse reflectance infrared Fourier transform (DRIFT) spectra of sand samples exhibit features reflecting their composition. Basic multivariate analysis (MVA) can be used to effectively sort subsets of homogeneous specimens collected from nearby locations, as well as pointing out similarities in composition among sands of different origins.…

  2. Source Determination of Red Gel Pen Inks using Raman Spectroscopy and Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy combined with Pearson's Product Moment Correlation Coefficients and Principal Component Analysis.

    Science.gov (United States)

    Mohamad Asri, Muhammad Naeim; Mat Desa, Wan Nur Syuhaila; Ismail, Dzulkiflee

    2018-01-01

    The potential combination of two nondestructive techniques, that is, Raman spectroscopy (RS) and attenuated total reflectance-fourier transform infrared (ATR-FTIR) spectroscopy with Pearson's product moment correlation (PPMC) coefficient (r) and principal component analysis (PCA) to determine the actual source of red gel pen ink used to write a simulated threatening note, was examined. Eighteen (18) red gel pens purchased from Japan and Malaysia from November to December 2014 where one of the pens was used to write a simulated threatening note were analyzed using RS and ATR-FTIR spectroscopy, respectively. The spectra of all the red gel pen inks including the ink deposited on the simulated threatening note gathered from the RS and ATR-FTIR analyses were subjected to PPMC coefficient (r) calculation and principal component analysis (PCA). The coefficients r = 0.9985 and r = 0.9912 for pairwise combination of RS and ATR-FTIR spectra respectively and similarities in terms of PC1 and PC2 scores of one of the inks to the ink deposited on the simulated threatening note substantiated the feasibility of combining RS and ATR-FTIR spectroscopy with PPMC coefficient (r) and PCA for successful source determination of red gel pen inks. The development of pigment spectral library had allowed the ink deposited on the threatening note to be identified as XSL Poppy Red (CI Pigment Red 112). © 2017 American Academy of Forensic Sciences.

  3. A Catalytic Path for Electrolyte Reduction in Lithium-Ion Cells Revealed by in Situ Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy

    KAUST Repository

    Shi, Feifei; Ross, Philip N.; Zhao, Hui; Liu, Gao; Somorjai, Gabor A.; Komvopoulos, Kyriakos

    2015-01-01

    © 2015 American Chemical Society. Although controlling the interfacial chemistry of electrodes in Li-ion batteries (LIBs) is crucial for maintaining the reversibility, electrolyte decomposition has not been fully understood. In this study, electrolyte decomposition on model electrode surfaces (Au and Sn) was investigated by in situ attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. Simultaneously obtained ATR-FTIR spectra and cyclic voltammetry measurements show that lithium ethylene dicarbonate and lithium propionate form on the Au electrode at 0.6 V, whereas diethyl 2,5-dioxahexane dicarboxylate and lithium propionate form on the Sn electrode surface at 1.25 V. A noncatalytic reduction path on the Au surface and a catalytic reduction path on the Sn surface are introduced to explain the surface dependence of the overpotential and product selectivity. This represents a new concept for explaining electrolyte reactions on the anode of LIBs. The present investigation shows that catalysis plays a dominant role in the electrolyte decomposition process and has important implications in electrode surface modification and electrolyte recipe selection, which are critical factors for enhancing the efficiency, durability, and reliability of LIBs.

  4. Application of micro-attenuated total reflectance Fourier transform infrared spectroscopy to ink examination in signatures written with ballpoint pen on questioned documents.

    Science.gov (United States)

    Nam, Yun Sik; Park, Jin Sook; Lee, Yeonhee; Lee, Kang-Bong

    2014-05-01

    Questioned documents examined in a forensic laboratory sometimes contain signatures written with ballpoint pen inks; these signatures were examined to assess the feasibility of micro-attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy as a forensic tool. Micro-ATR FTIR spectra for signatures written with 63 ballpoint pens available commercially in Korea were obtained and used to construct an FTIR spectral database. A library-searching program was utilized to identify the manufacturer, blend, and model of each black ballpoint pen ink based upon their FTIR peak intensities, positions, and patterns in the spectral database. This FTIR technique was also successfully used in determining the sequence of homogeneous line intersections from the crossing lines of two ballpoint pen signatures. We have demonstrated with a set of sample documents that micro-ATR FTIR is a viable nondestructive analytical method that can be used to identify the origin of the ballpoint pen ink used to mark signatures. © 2014 American Academy of Forensic Sciences.

  5. Application of multivariate chemometric techniques for simultaneous determination of five parameters of cottonseed oil by single bounce attenuated total reflectance Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Talpur, M Younis; Kara, Huseyin; Sherazi, S T H; Ayyildiz, H Filiz; Topkafa, Mustafa; Arslan, Fatma Nur; Naz, Saba; Durmaz, Fatih; Sirajuddin

    2014-11-01

    Single bounce attenuated total reflectance (SB-ATR) Fourier transform infrared (FTIR) spectroscopy in conjunction with chemometrics was used for accurate determination of free fatty acid (FFA), peroxide value (PV), iodine value (IV), conjugated diene (CD) and conjugated triene (CT) of cottonseed oil (CSO) during potato chips frying. Partial least square (PLS), stepwise multiple linear regression (SMLR), principal component regression (PCR) and simple Beer׳s law (SBL) were applied to develop the calibrations for simultaneous evaluation of five stated parameters of cottonseed oil (CSO) during frying of French frozen potato chips at 170°C. Good regression coefficients (R(2)) were achieved for FFA, PV, IV, CD and CT with value of >0.992 by PLS, SMLR, PCR, and SBL. Root mean square error of prediction (RMSEP) was found to be less than 1.95% for all determinations. Result of the study indicated that SB-ATR FTIR in combination with multivariate chemometrics could be used for accurate and simultaneous determination of different parameters during the frying process without using any toxic organic solvent. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. A Catalytic Path for Electrolyte Reduction in Lithium-Ion Cells Revealed by in Situ Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy

    KAUST Repository

    Shi, Feifei

    2015-03-11

    © 2015 American Chemical Society. Although controlling the interfacial chemistry of electrodes in Li-ion batteries (LIBs) is crucial for maintaining the reversibility, electrolyte decomposition has not been fully understood. In this study, electrolyte decomposition on model electrode surfaces (Au and Sn) was investigated by in situ attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. Simultaneously obtained ATR-FTIR spectra and cyclic voltammetry measurements show that lithium ethylene dicarbonate and lithium propionate form on the Au electrode at 0.6 V, whereas diethyl 2,5-dioxahexane dicarboxylate and lithium propionate form on the Sn electrode surface at 1.25 V. A noncatalytic reduction path on the Au surface and a catalytic reduction path on the Sn surface are introduced to explain the surface dependence of the overpotential and product selectivity. This represents a new concept for explaining electrolyte reactions on the anode of LIBs. The present investigation shows that catalysis plays a dominant role in the electrolyte decomposition process and has important implications in electrode surface modification and electrolyte recipe selection, which are critical factors for enhancing the efficiency, durability, and reliability of LIBs.

  7. Adsorption of water and butanol in silicalite-1 film studied with in situ attenuated total reflectance-Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Farzaneh, Amirfarrokh; Zhou, Ming; Potapova, Elisaveta; Bacsik, Zoltán; Ohlin, Lindsay; Holmgren, Allan; Hedlund, Jonas; Grahn, Mattias

    2015-05-05

    Biobutanol produced by, e.g., acetone-butanol-ethanol (ABE) fermentation is a promising alternative to petroleum-based chemicals as, e.g., solvent and fuel. Recovery of butanol from dilute fermentation broths by hydrophobic membranes and adsorbents has been identified as a promising route. In this work, the adsorption of water and butanol vapor in a silicalite-1 film was studied using in situ attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy to better understand the adsorption properties of silicalite-1 membranes and adsorbents. Single-component adsorption isotherms were determined in the temperature range of 35-120 °C, and the Langmuir model was successfully fitted to the experimental data. The adsorption of butanol is very favorable compared to that of water. When the silicalite-1 film was exposed to a butanol/water vapor mixture with 15 mol % butanol (which is the vapor composition of an aqueous solution containing 2 wt % butanol, a typical concentration in an ABE fermentation broth, i.e., the composition of the gas obtained from gas stripping of an ABE broth) at 35 °C, the adsorption selectivity toward butanol was as high as 107. These results confirm that silicalite-1 quite selectively adsorbs hydrocarbons from vapor mixtures. To the best of our knowledge, this is the first comprehensive study on the adsorption of water and butanol in silicalite-1 from vapor phase.

  8. Capabilities and limitations of handheld Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) for the analysis of colourants and binders in 20th-century reverse paintings on glass

    Science.gov (United States)

    Steger, Simon; Stege, Heike; Bretz, Simone; Hahn, Oliver

    2018-04-01

    A non-invasive method has been carried out to show the capabilities and limitations of Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) for identifying of colourants and binders in modern reverse glass paintings. For this purpose, the reverse glass paintings "Zwei Frauen am Tisch" (1920-22), "Bäume" (1946) (both by Heinrich Campendonk), "Lofoten" (1933) (Edith Campendonk-van Leckwyck) and "Ohne Titel" (1954) (Marianne Uhlenhuth), were measured. In contrast to other techniques (e.g. panel and mural painting), the paint layers are applied in reverse succession. In multi-layered paint systems, the front paint layer may no longer be accessible. The work points out the different spectral appearance of a given substance (gypsum, basic lead white) in reverse glass paintings. However, inverted bands, band overlapping and derivative-shaped spectral features can be interpreted by comparing the spectra from the paintings with spectra from pure powders and pigment/linseed oil mock-ups. Moreover, the work focuses on this method's capabilities in identifying synthetic organic pigments (SOP). Reference spectra of three common SOP (PG7, PY1, PR83) were obtained from powders and historical colour charts. We identified PR83 and PY1 in two reverse glass paintings, using the measured reference spectra. The recorded DRIFTS spectra of pure linseed oil, gum Arabic, mastic, polyvinyl acetate resin and bees wax can be used to classify the binding media of the measured paintings.

  9. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy on Intact Dried Leaves of Sage (Salvia officinalis L.): Accelerated Chemotaxonomic Discrimination and Analysis of Essential Oil Composition.

    Science.gov (United States)

    Gudi, Gennadi; Krähmer, Andrea; Krüger, Hans; Schulz, Hartwig

    2015-10-07

    Sage (Salvia officinalis L.) is cultivated worldwide for its aromatic leaves, which are used as herbal spice, and for phytopharmaceutical applications. Fast analytical strategies for essential oil analysis, performed directly on plant material, would reduce the delay between sampling and analytical results. This would enhance product quality by improving technical control of cultivation. The attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) method described here provides a reliable calibration model for quantification of essential oil components [EOCs; R(2) = 0.96; root-mean-square error of cross-validation (RMSECV) = 0.249 mL 100 g(-1) of dry matter (DM); and range = 1.115-5.280 mL 100 g(-1) of DM] and main constituents [e.g., α-thujone/β-thujone; R(2) = 0.97/0.86; RMSECV = 0.0581/0.0856 mL 100 g(-1) of DM; and range = 0.010-1.252/0.005-0.893 mL 100 g(-1) of DM] directly on dried intact leaves of sage. Except for drying, no further sample preparation is required for ATR-FTIR, and the measurement time of less than 5 min per sample contrasts with the most common alternative of hydrodistillation followed by gas chromatography analysis, which can take several hours per sample.

  10. Spectral Mining for Discriminating Blood Origins in the Presence of Substrate Interference via Attenuated Total Reflection Fourier Transform Infrared Spectroscopy: Postmortem or Antemortem Blood?

    Science.gov (United States)

    Takamura, Ayari; Watanabe, Ken; Akutsu, Tomoko; Ikegaya, Hiroshi; Ozawa, Takeaki

    2017-09-19

    Often in criminal investigations, discrimination of types of body fluid evidence is crucially important to ascertain how a crime was committed. Compared to current methods using biochemical techniques, vibrational spectroscopic approaches can provide versatile applicability to identify various body fluid types without sample invasion. However, their applicability is limited to pure body fluid samples because important signals from body fluids incorporated in a substrate are affected strongly by interference from substrate signals. Herein, we describe a novel approach to recover body fluid signals that are embedded in strong substrate interferences using attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy and an innovative multivariate spectral processing. This technique supported detection of covert features of body fluid signals, and then identified origins of body fluid stains on substrates. We discriminated between ATR FT-IR spectra of postmortem blood (PB) and those of antemortem blood (AB) by creating a multivariate statistics model. From ATR FT-IR spectra of PB and AB stains on interfering substrates (polyester, cotton, and denim), blood-originated signals were extracted by a weighted linear regression approach we developed originally using principal components of both blood and substrate spectra. The blood-originated signals were finally classified by the discriminant model, demonstrating high discriminant accuracy. The present method can identify body fluid evidence independently of the substrate type, which is expected to promote the application of vibrational spectroscopic techniques in forensic body fluid analysis.

  11. Use of total internal reflection Raman (TIR) and attenuated total reflection infrared (ATR-IR) spectroscopy to analyze component separation in thin offset ink films after setting on coated paper surfaces.

    Science.gov (United States)

    Kivioja, Antti; Hartus, Timo; Vuorinen, Tapani; Gane, Patrick; Jääskeläinen, Anna-Stiina

    2013-06-01

    The interactive behavior of ink constituents with porous substrates during and after the offset print process has an important effect on the quality of printed products. To help elucidate the distribution of ink components between the retained ink layer and the substrate, a variety of spectroscopic and microscopic analysis techniques have been developed. This paper describes for the first time the use of total internal reflection (TIR) Raman spectroscopy to analyze the penetration behavior of separated offset ink components (linseed oil, solid color pigment) in coated papers providing chemically intrinsic information rapidly, nondestructively, and with minimal sample preparation. In addition, the already widely applied technique of attenuated total reflection infrared spectroscopy (ATR-IR) was evaluated in parallel and compared. The results of the ATR-IR Raman clearly revealed an improvement in uppermost depth resolution compared with values previously published from other nondestructive techniques, and the method is shown to be capable of providing new knowledge of the setting of thin (0.25-2 μm) offset ink films, allowing the spreading and the penetration behavior on physically different paper coating surfaces to be studied.

  12. Electrochemical, atomic force microscopy and infrared reflection absorption spectroscopy studies of pre-formed mussel adhesive protein films on carbon steel for corrosion protection

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan, E-mail: fanzhang@kth.se [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Div. of Surface and Corrosion Science, Drottning Kristinas vaeg.51, SE-100 44 Stockholm (Sweden); Pan, Jinshan [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Div. of Surface and Corrosion Science, Drottning Kristinas vaeg.51, SE-100 44 Stockholm (Sweden); Claesson, Per Martin [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Div. of Surface and Corrosion Science, Drottning Kristinas vaeg.51, SE-100 44 Stockholm (Sweden); Institute for Surface Chemistry, P.O. Box 5607, SE-114 86 Stockholm (Sweden); Brinck, Tore [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Physical Chemistry, Division of Physical Chemistry, Teknikringen 36, SE-10044 Stockholm (Sweden)

    2012-10-01

    Electrochemical measurements, in situ and ex situ atomic force microscopy (AFM) experiments and infrared reflection absorption spectroscopy (IRAS) analysis were performed to investigate the formation and stability as well as corrosion protection properties of mussel adhesive protein (Mefp-1) films on carbon steel, and the influence of cross-linking by NaIO{sub 4} oxidation. The in situ AFM measurements show flake-like adsorbed protein aggregates in the film formed at pH 9. The ex situ AFM images indicate multilayer-like films and that the film becomes more compact and stable in NaCl solution after the cross-linking. The IRAS results reveal the absorption bands of Mefp-1 on carbon steel before and after NaIO{sub 4} induced oxidation of the pre-adsorbed protein. Within a short exposure time, a certain corrosion protection effect was noted for the pre-formed Mefp-1 film in 0.1 M NaCl solution. Cross-linking the pre-adsorbed film by NaIO{sub 4} oxidation significantly enhanced the protection efficiency by up to 80%. - Highlights: Black-Right-Pointing-Pointer Mussel protein was tested as 'green' corrosion protection strategy for steel. Black-Right-Pointing-Pointer At pH 9, the protein adsorbs on carbon steel and forms a multilayer-like film. Black-Right-Pointing-Pointer NaIO{sub 4} leads to structural changes and cross-linking of the protein film. Black-Right-Pointing-Pointer Cross-linking results in a dense and compact film with increased stability. Black-Right-Pointing-Pointer Cross-linking of preformed film significantly enhances the corrosion protection.

  13. Using visible and near-infrared diffuse reflectance spectroscopy for predicting soil properties based on regression with peaks parameters as derived from continuum-removed spectra

    Science.gov (United States)

    Vasat, Radim; Klement, Ales; Jaksik, Ondrej; Kodesova, Radka; Drabek, Ondrej; Boruvka, Lubos

    2014-05-01

    Visible and near-infrared diffuse reflectance spectroscopy (VNIR-DRS) provides a rapid and inexpensive tool for simultaneous prediction of a variety of soil properties. Usually, some sophisticated multivariate mathematical or statistical methods are employed in order to extract the required information from the raw spectra measurement. For this purpose especially the Partial least squares regression (PLSR) and Support vector machines (SVM) are the most frequently used. These methods generally benefit from the complexity with which the soil spectra are treated. But it is interesting that also techniques that focus only on a single spectral feature, such as a simple linear regression with selected continuum-removed spectra (CRS) characteristic (e.g. peak depth), can often provide competitive results. Therefore, we decided to enhance the potential of CRS taking into account all possible CRS peak parameters (area, width and depth) and develop a comprehensive methodology based on multiple linear regression approach. The eight considered soil properties were oxidizable carbon content (Cox), exchangeable (pHex) and active soil pH (pHa), particle and bulk density, CaCO3 content, crystalline and amorphous (Fed) and amorphous Fe (Feox) forms. In four cases (pHa, bulk density, Fed and Feox), of which two (Fed and Feox) were predicted reliably accurately (0.50 interestingly, in the case of particle density, the presented approach outperformed the PLSR and SVM dramatically offering a fairly accurate prediction (R2cv = 0.827) against two failures (R2cv = 0.034 and 0.121 for PLSR and SVM, resp.). In last two cases (Cox and CaCO3) a slightly worse results were achieved then with PLSR and SVM with overall fairly accurate prediction (R2cv > 0.80). Acknowledgment: Authors acknowledge the financial support of the Ministry of Agriculture of the Czech Republic (grant No. QJ1230319).

  14. Measurement of conjugated linoleic acid (CLA) in CLA-rich soy oil by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR).

    Science.gov (United States)

    Kadamne, Jeta V; Jain, Vishal P; Saleh, Mohammed; Proctor, Andrew

    2009-11-25

    Conjugated linoleic acid (CLA) isomers in oils are currently measured as fatty acid methyl esters by a gas chromatography-flame ionization detector (GC-FID) technique, which requires approximately 2 h to complete the analysis. Hence, we aim to develop a method to rapidly determine CLA isomers in CLA-rich soy oil. Soy oil with 0.38-25.11% total CLA was obtained by photo-isomerization of 96 soy oil samples for 24 h. A sample was withdrawn at 30 min intervals with repeated processing using a second batch of oil. Six replicates of GC-FID fatty acid analysis were conducted for each oil sample. The oil samples were scanned using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and the spectrum was collected. Calibration models were developed using partial least-squares (PLS-1) regression using Unscrambler software. Models were validated using a full cross-validation technique and tested using samples that were not included in the calibration sample set. Measured and predicted total CLA, trans,trans CLA isomers, total mono trans CLA isomers, trans-10,cis-12 CLA, trans-9,cis-11 CLA and cis-10,trans-12 CLA, and cis-9,trans-11 CLA had cross-validated coefficients of determinations (R2v) of 0.97, 0.98, 0.97, 0.98, 0.97, and 0.99 and corresponding root-mean-square error of validation (RMSEV) of 1.14, 0.69, 0.27, 0.07, 0.14, and 0.07% CLA, respectively. The ATR-FTIR technique is a rapid and less expensive method for determining CLA isomers in linoleic acid photo-isomerized soy oil than GC-FID.

  15. Quantitative determination of polyphosphate in sediments using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy and partial least squares regression.

    Science.gov (United States)

    Khoshmanesh, Aazam; Cook, Perran L M; Wood, Bayden R

    2012-08-21

    Phosphorus (P) is a major cause of eutrophication and subsequent loss of water quality in freshwater ecosystems. A major part of the flux of P to eutrophic lake sediments is organically bound or of biogenic origin. Despite the broad relevance of polyphosphate (Poly-P) in bioremediation and P release processes in the environment, its quantification is not yet well developed for sediment samples. Current methods possess significant disadvantages because of the difficulties associated with using a single extractant to extract a specific P compound without altering others. A fast and reliable method to estimate the quantitative contribution of microorganisms to sediment P release processes is needed, especially when an excessive P accumulation in the form of polyphosphate (Poly-P) occurs. Development of novel approaches for application of emerging spectroscopic techniques to complex environmental matrices such as sediments significantly contributes to the speciation models of P mobilization, biogeochemical nutrient cycling and development of nutrient models. In this study, for the first time Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy in combination with partial least squares (PLS) was used to quantify Poly-P in sediments. To reduce the high absorption matrix components in sediments such as silica, a physical extraction method was developed to separate sediment biological materials from abiotic particles. The aim was to achieve optimal separation of the biological materials from sediment abiotic particles with minimum chemical change in the sample matrix prior to ATR-FTIR analysis. Using a calibration set of 60 samples for the PLS prediction models in the Poly-P concentration range of 0-1 mg g(-1) d.w. (dry weight of sediment) (R(2) = 0.984 and root mean square error of prediction RMSEP = 0.041 at Factor-1) Poly-P could be detected at less than 50 μg g(-l) d.w. Using this technique, there is no solvent extraction or chemical

  16. Application of reflectance colorimeter measurements and infrared spectroscopy methods to rapid and nondestructive evaluation of carotenoids content in apricot (Prunus armeniaca L.).

    Science.gov (United States)

    Ruiz, David; Reich, Maryse; Bureau, Sylvie; Renard, Catherine M G C; Audergon, Jean-Marc

    2008-07-09

    The importance of carotenoid content in apricot (Prunus armeniaca L.) is recognized not only because of the color that they impart but also because of their protective activity against human diseases. Current methods to assess carotenoid content are time-consuming, expensive, and destructive. In this work, the application of rapid and nondestructive methods such as colorimeter measurements and infrared spectroscopy has been evaluated for carotenoid determination in apricot. Forty apricot genotypes covering a wide range of peel and flesh colors have been analyzed. Color measurements on the skin and flesh ( L*, a*, b*, hue, chroma, and a*/ b* ratio) as well as Fourier transform near-infrared spectroscopy (FT-NIR) on intact fruits and Fourier transform mid-infrared spectroscopy (FT-MIR) on ground flesh were correlated with the carotenoid content measured by high-performance liquid chromatography. A high variability in color values and carotenoid content was observed. Partial least squares regression analyses between beta-carotene content and provitamin A activity and color measurements showed a high fit in peel, flesh, and edible apricot portion (R(2) ranged from 0.81 to 0.91) and low prediction error. Regression equations were developed for predicting carotenoid content by using color values, which appeared as a simple, rapid, reliable, and nondestructive method. However, FT-NIR and FT-MIR models showed very low R(2) values and very high prediction errors for carotenoid content.

  17. The potential of mid- and near-infrared diffuse reflectance spectroscopy for determining major- and trace-element concentrations in soils from a geochemical survey of North America

    Science.gov (United States)

    Reeves, J. B.; Smith, D.B.

    2009-01-01

    In 2004, soils were collected at 220 sites along two transects across the USA and Canada as a pilot study for a planned soil geochemical survey of North America (North American Soil Geochemical Landscapes Project). The objective of the current study was to examine the potential of diffuse reflectance (DR) Fourier Transform (FT) mid-infrared (mid-IR) and near-infrared (NIRS) spectroscopy to reduce the need for conventional analysis for the determination of major and trace elements in such continental-scale surveys. Soil samples (n = 720) were collected from two transects (east-west across the USA, and north-south from Manitoba, Canada to El Paso, Texas (USA), n = 453 and 267, respectively). The samples came from 19 USA states and the province of Manitoba in Canada. They represented 31 types of land use (e.g., national forest, rangeland, etc.), and 123 different land covers (e.g., soybeans, oak forest, etc.). The samples represented a combination of depth-based sampling (0-5 cm) and horizon-based sampling (O, A and C horizons) with 123 different depths identified. The set was very diverse with few samples similar in land use, land cover, etc. All samples were analyzed by conventional means for the near-total concentration of 49 analytes (Ctotal, Ccarbonate and Corganic, and 46 major and trace elements). Spectra were obtained using dried, ground samples using a Digilab FTS-7000 FT spectrometer in the mid- (4000-400 cm-1) and near-infrared (10,000-4000 cm-1) at 4 cm-1 resolution (64 co-added scans per spectrum) using a Pike AutoDIFF DR autosampler. Partial least squares calibrations were develop using: (1) all samples as a calibration set; (2) samples evenly divided into calibration and validation sets based on spectral diversity; and (3) samples divided to have matching analyte concentrations in calibration and validation sets. In general, results supported the conclusion that neither mid-IR nor NIRS would be particularly useful in reducing the need for conventional

  18. Infrared spectroscopy of fluid lipid bilayers.

    Science.gov (United States)

    Hull, Marshall C; Cambrea, Lee R; Hovis, Jennifer S

    2005-09-15

    Infrared spectroscopy is a powerful technique for examining lipid bilayers; however, it says little about the fluidity of the bilayer-a key physical aspect. It is shown here that it is possible to both acquire spectroscopic data of supported lipid bilayer samples and make measurements of the membrane fluidity. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FT-IR) is used to obtain the spectroscopic information and fluorescence recovery after photobleaching (FRAP) is used to determine the fluidity of the samples. In the infrared spectra of lipid bilayers composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, the following major peaks were observed; nu(as)(CH3) 2954 cm(-1), nu(s)(CH3) 2870 cm(-1), nu(as)(CH2) 2924 cm(-1), nu(s)(CH2) 2852 cm(-1), nu(C=O) 1734 cm(-1), delta(CH2) 1463-1473 cm(-1), nu(as)(PO2-) 1226 cm(-1), nu(s)(PO2-) 1084 cm(-1), and nu(as)(N+(CH3)3) 973 cm(-1). The diffusion coefficient of the same lipid bilayer was measured to be 3.5 +/- 0.5 micom(2)/s with visual recovery also noted through use of epifluorescence microscopy. FRAP and visual data confirm the formation of a uniform, mobile supported lipid bilayer. The combination of ATR-FT-IR and FRAP provides complementary data giving a more complete picture of fully hydrated model membrane systems.

  19. Estimates of diet selection in cattle grazing cornstalk residues by measurement of chemical composition and near infrared reflectance spectroscopy of diet samples collected by ruminal evacuation.

    Science.gov (United States)

    Petzel, Emily A; Smart, Alexander J; St-Pierre, Benoit; Selman, Susan L; Bailey, Eric A; Beck, Erin E; Walker, Julie A; Wright, Cody L; Held, Jeffrey E; Brake, Derek W

    2018-05-04

    Six ruminally cannulated cows (570 ± 73 kg) fed corn residues were placed in a 6 × 6 Latin square to evaluate predictions of diet composition from ruminally collected diet samples. After complete ruminal evacuation, cows were fed 1-kg meals (dry matter [DM]-basis) containing different combinations of cornstalk and leaf and husk (LH) residues in ratios of 0:100, 20:80, 40:60, 60:40, 80:20, and 100:0. Diet samples from each meal were collected by removal of ruminal contents after 1-h and were either unrinsed, hand-rinsed or machine-rinsed to evaluate effects of endogenous compounds on predictions of diet composition. Diet samples were analyzed for neutral (NDF) and acid (ADF) detergent fiber, acid detergent insoluble ash (ADIA), acid detergent lignin (ADL), crude protein (CP), and near infrared reflectance spectroscopy (NIRS) to calculate diet composition. Rinsing type increased NDF and ADF content and decreased ADIA and CP content of diet samples (P content of diet samples. Differences in concentration between cornstalk and LH residues within each chemical component were standardized by calculating a coefficient of variation (CV). Accuracy and precision of estimates of diet composition were analyzed by regressing predicted diet composition and known diet composition. Predictions of diet composition were improved by increasing differences in concentration of chemical components between cornstalk and LH residues up to a CV of 22.6 ± 5.4%. Predictions of diet composition from unrinsed ADIA and machine-rinsed NIRS had the greatest accuracy (slope = 0.98 and 0.95, respectively) and large coefficients of determination (r2 = 0.86 and 0.74, respectively). Subsequently, a field study (Exp. 2) was performed to evaluate predictions of diet composition in cattle (646 ± 89 kg) grazing corn residue. Five cows were placed in 1 of 10 paddocks and allowed to graze continuously or to strip-graze corn residues. Predictions of diet composition from ADIA, ADL, and NIRS did not

  20. Characterization of superconducting thin films by infrared reflection

    International Nuclear Information System (INIS)

    Gervais, F.

    1988-01-01

    Infrared reflectivity spectroscopy is shown to be a powerful tool to characterize the new high-Tc oxide superconductors since it gives information about the superconducting gap, phonons, plasmon and possibly low-energy electronic excitations such as excitons, information relevant to understand the mechanism of superconductivity [fr

  1. Infrared and Raman spectroscopy: principles and spectral interpretation

    National Research Council Canada - National Science Library

    Larkin, Peter

    2011-01-01

    "Infrared and Raman Spectroscopy: Principles and Spectral Interpretation explains the background, core principles and tests the readers understanding of the important techniques of Infrared and Raman Spectroscopy...

  2. Systematic Assessment of Attenuated Total Reflectance-Fourier Transforms Infrared Spectroscopy Coupled with Multivariate Analysis for Forensic Analysis of Black Ball-point Pen Inks

    International Nuclear Information System (INIS)

    Lee, L.C.; Mohamed Rozali Othman; Pua, H.; Lee, L.C.

    2012-01-01

    This manuscript aims to provide a new and non-destructive method for systematic analysis of inks on a questioned document. Ink samples were analyzed in situ on the paper substrate by micro-ATR-FTIR spectroscopy and the data obtained was processed and evaluated by a series of multivariate chemometrics. Absorbance value from wavenumbers of 2000-675 cm -1 were first processed by cluster analysis (CA), followed by principal component analysis (PCA) to form a set of new variables. Subsequently, the variables set was used for classification, differentiation and identification of 155 sample pens that comprise nine different brands. Results show that nine black ball-point pen brands could be classified into three main groups via discriminant analysis (DA). Differentiation analyses of nine different pen brands performed using one-way ANOVA indicated only two pairs of brands cannot be differentiated at 95 % confidence interval. Finally an identification flow chart was proposed to determine the brand of unknown pen inks. As a conclusion, the proposed method for extracting and creating a new variable set from infrared spectrum was evaluated to be satisfactory for systematic analysis of inks based on their infrared spectrum. (author)

  3. Application of infrared spectroscopy for diagnosis of kidney tumor tissue

    OpenAIRE

    Bandzevičiūtė, Rimantė

    2016-01-01

    Application of Infrared Spectroscopy for Diagnosis of Kidney Tumor Tissue It is possible to apply the technique of an attenuated total reflection of infrared radiation (ATR IR) for the characterisation of the removed tissues during the surgery. Application of this method for interstitium of the removed tissue does not require any specific sample preparation. For this reason ATR IR technique applied for the interstitium allows to get information about tissues immediately after surgical operati...

  4. CVD molybdenum films of high infrared reflectance

    Energy Technology Data Exchange (ETDEWEB)

    Carver, G. E.

    1979-01-01

    Molybdenum thin films of high infrared reflectance have been deposited by pyrolytic decomposition of molybdenum carbonyl (Mo(CO)/sub 6/), and by hydrogen reduction of molybdenum pentachloride (MoCl/sub 5/). Reflectance values within 0.7% of the reflectance of supersmooth bulk molybdenum have been attained by annealing films of lower reflectance in both reducing and non-reducing atmospheres. All depositions and anneals proceed at atmospheric pressure, facilitating a continuous, flow-through fabrication. These reflectors combine the high temperature stability of molybdenum thin films with the infrared reflectance of a material such as aluminum. Deposition from Mo(CO)/sub 6/ under oxidizing conditions, and subsequent anneal in a reducing atmosphere, results in films that combine high solar absorptance with low thermal emittance. If anti-reflected, black molybdenum films can serve as highly selective single layer photothermal converters. Structural, compositional, and crystallographic properties have been measured after both deposition and anneal.

  5. A methodological approach to study the stability of selected watercolours for painting reintegration, through reflectance spectrophotometry, Fourier transform infrared spectroscopy and hyperspectral imaging

    Science.gov (United States)

    Pelosi, Claudia; Capobianco, Giuseppe; Agresti, Giorgia; Bonifazi, Giuseppe; Morresi, Fabio; Rossi, Sara; Santamaria, Ulderico; Serranti, Silvia

    2018-06-01

    The aim of this work is to investigate the stability to simulated solar radiation of some paintings samples through a new methodological approach adopting non-invasive spectroscopic techniques. In particular, commercial watercolours and iron oxide based pigments were used, these last ones being prepared for the experimental by gum Arabic in order to propose a possible substitute for traditional reintegration materials. Reflectance spectrophotometry in the visible range and Hyperspectral Imaging in the short wave infrared were chosen as non-invasive techniques for evaluation the stability to irradiation of the chosen pigments. These were studied before and after artificial ageing procedure performed in Solar Box chamber under controlled conditions. Data were treated and elaborated in order to evaluate the sensitivity of the chosen techniques in identifying the variations on paint layers, induced by photo-degradation, before they could be observed by eye. Furthermore a supervised classification method for monitoring the painted surface changes adopting a multivariate approach was successfully applied.

  6. Complex refractive index measurements for BaF 2 and CaF 2 via single-angle infrared reflectance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kelly-Gorham, Molly Rose K.; DeVetter, Brent M.; Brauer, Carolyn S.; Cannon, Bret D.; Burton, Sarah D.; Bliss, Mary; Johnson, Timothy J.; Myers, Tanya L.

    2017-10-01

    We have re-investigated the optical constants n and k for the homologous series of inorganic salts barium fluoride (BaF2) and calcium fluoride (CaF2) using a single-angle near-normal incidence reflectance device in combination with a calibrated Fourier transform infrared (FTIR) spectrometer. Our results are in good qualitative agreement with most previous works. However, certain features of the previously published data near the reststrahlen band exhibit distinct differences in spectral characteristics. Notably, our measurements of BaF2 do not include a spectral feature in the ~250 cm-1 reststrahlen band that was previously published. Additionally, CaF2 exhibits a distinct wavelength shift relative to the model derived from previously published data. We confirmed our results with recently published works that use significantly more modern instrumentation and data reduction techniques

  7. Rapid, nondestructive estimation of surface polymer layer thickness using attenuated total reflection fourier transform infrared (ATR FT-IR) spectroscopy and synthetic spectra derived from optical principles.

    Science.gov (United States)

    Weinstock, B André; Guiney, Linda M; Loose, Christopher

    2012-11-01

    We have developed a rapid, nondestructive analytical method that estimates the thickness of a surface polymer layer with high precision but unknown accuracy using a single attenuated total reflection Fourier transform infrared (ATR FT-IR) measurement. Because the method is rapid, nondestructive, and requires no sample preparation, it is ideal as a process analytical technique. Prior to implementation, the ATR FT-IR spectrum of the substrate layer pure component and the ATR FT-IR and real refractive index spectra of the surface layer pure component must be known. From these three input spectra a synthetic mid-infrared spectral matrix of surface layers 0 nm to 10,000 nm thick on substrate is created de novo. A minimum statistical distance match between a process sample's ATR FT-IR spectrum and the synthetic spectral matrix provides the thickness of that sample. We show that this method can be used to successfully estimate the thickness of polysulfobetaine surface modification, a hydrated polymeric surface layer covalently bonded onto a polyetherurethane substrate. A database of 1850 sample spectra was examined. Spectrochemical matrix-effect unknowns, such as the nonuniform and molecularly novel polysulfobetaine-polyetherurethane interface, were found to be minimal. A partial least squares regression analysis of the database spectra versus their thicknesses as calculated by the method described yielded an estimate of precision of ±52 nm.

  8. Characterization of silver halide fiber optics and hollow silica waveguides for use in the construction of a mid-infrared attenuated total reflection fourier transform infrared (ATR FT-IR) spectroscopy probe.

    Science.gov (United States)

    Damin, Craig A; Sommer, André J

    2013-11-01

    Advances in fiber optic materials have allowed for the construction of fibers and waveguides capable of transmitting infrared radiation. An investigation of the transmission characteristics associated with two commonly used types of infrared-transmitting fibers/waveguides for prospective use in a fiber/waveguide-coupled attenuated total internal reflection (ATR) probe was performed. Characterization of silver halide polycrystalline fiber optics and hollow silica waveguides was done on the basis of the transmission of infrared light using a conventional fiber optic coupling accessory and an infrared microscope. Using the fiber optic coupling accessory, the average percent transmission for three silver halide fibers was 18.1 ± 6.1% relative to a benchtop reflection accessory. The average transmission for two hollow waveguides (HWGs) using the coupling accessory was 8.0 ± 0.3%. (Uncertainties in the relative percent transmission represent the standard deviations.) Reduced transmission observed for the HWGs was attributed to the high numerical aperture of the coupling accessory. Characterization of the fibers/waveguides using a zinc selenide lens objective on an infrared microscope indicated 24.1 ± 7.2% of the initial light input into the silver halide fibers was transmitted. Percent transmission obtained for the HWGs was 98.7 ± 0.1%. Increased transmission using the HWGs resulted from the absence or minimization of insertion and scattering losses due to the hollow air core and a better-matched numerical aperture. The effect of bending on the transmission characteristics of the fibers/waveguides was also investigated. Significant deviations in the transmission of infrared light by the solid-core silver halide fibers were observed for various bending angles. Percent transmission greater than 98% was consistently observed for the HWGs at the bending angles. The combined benefits of high percent transmission, reproducible instrument responses, and increased bending

  9. The structure of oleamide films at the aluminum/oil interface and aluminum/air interface studied by Sum Frequency Generation (SFG) vibrational spectroscopy and Reflection Absorption Infrared Spectroscopy (RAIRS).

    Science.gov (United States)

    Casford, Michael T L; Davies, Paul B

    2009-08-01

    The structure of oleamide (cis-9-octadecenamide) films on aluminum has been investigated by sum frequency generation vibrational spectroscopy (SFG) and reflection absorption infrared spectroscopy (RAIRS). Three different film deposition strategies were investigated: (i) films formed by equilibrium adsorption from oleamide solutions in oil, (ii) Langmuir-Blodgett films cast at 1 and 25 mN m(-1), (iii) thick spin-cast films. Both L-B and spin-cast films were examined in air and under oil. The adsorbate formed in the 1 mN m(-1) film in air showed little orientational order. For this film, the spectroscopic results and the ellipsometric thickness point to a relatively conformationally disordered monolayer that is oriented principally in the plane of the interface. Direct adsorption to the metal interface from oil results in SFG spectra of oleamide that are comparable to those observed for the 1 mN m(-1) L-B film in air. In contrast, SFG and RAIRS results for the 25 mN m(-1) film in air and SFG spectra of the spin-cast film in air both show strong conformational ordering and orientational alignment normal to the interface. The 25 mN m(-1) film has an ellipsometric thickness almost twice that of the 1 mN m(-1) L-B film. Taken in combination with the spectroscopic results, this is indicative of a well packed monolayer in air in which the hydrocarbon chain is in an essentially defect-free extended conformation with the methyl terminus oriented away from the surface. A similar structure is also deduced for the surface of the spin-cast film in air. Upon immersion of the 25 mN m(-1) L-B film in oil the SFG spectra show that this film rapidly adopts a relatively disordered structure similar to that seen for the 1 mN m(-1) L-B film in air. Immersion of the spin-cast film in oil results in the gradual disordering of the amide film over a period of several days until the observed spectra become essentially identical to those observed for direct adsorption of oleamide from oil.

  10. Infrared reflection nebulae in Orion Molecular Cloud

    International Nuclear Information System (INIS)

    Pendleton, Y.; Werner, M.W.; Capps, R.; Lester, D.; Hawaii Univ., Honolulu; Texas Univ., Austin)

    1986-01-01

    New observations of Orion Molecular Cloud 2 have been made from 1 to 100 microns using the NASA Infrared Telescope Facility and the Kuiper Airborne Observatory. An extensive program of polarimetry, photometry, and spectrophotometry has shown that the extended emission regions associated with two of the previously known near-infrared sources, IRS 1 and IRS 4, are infrared reflection nebulae, and that the compact sources IRS 1 and IRS 4 are the main luminosity sources in the cloud. The constraints from the far-infrared observations and an analysis of the scattered light from the IRS 1 nebula show that OMC-2/IRS 1 can be characterized by L of 500 solar luminosities or less and T of roughly 1000 K. The near-infrared albedo of the grains in the IRS 1 nebula is greater than 0.08. 27 references

  11. Near infrared spectroscopy and exercise

    International Nuclear Information System (INIS)

    Angus, Caroline

    2002-01-01

    Near infrared spectroscopy (NIRS) provides a non-invasive method for the continuous monitoring of changes in tissue oxygenation and blood volume during aerobic exercise. During incremental exercise in adult subjects there was a positive correlation between lactate threshold (measured by blood sampling) and changes in the rate of muscle deoxygenation (measured by NIRS). However, the 7% failure rate for the NIRS test mitigated against the general use of this method. NIRS did not provide a valid method for LT determination in an adolescent population. NIRS was then used to examine whether haemodynamic changes could be a contributing factor to the mechanism underlying the cross-transfer effect. During a one-legged incremental aerobic exercise test the muscle was more deoxygenated in the exercising leg than in the non-exercising leg, consistent with oxygen consumption outstripping blood flow to the exercising limb. However, muscle blood volume increased equally in both legs. This suggests that blood flow may be raised to similar levels in both the legs; although local factors may signal an increase in blood volume, this effect is expressed in both legs. Muscle blood flow and changes in muscle blood volume were then measured directly by NIRS during an incremental one-arm aerobic exercise test. There was no significant difference in either blood volume or blood flow in the two arms at the end of the test. In the non-exercising arm changes in blood flow and blood volume were measured throughout the protocol. At higher exercise intensities, blood volume continued to rise as muscle blood flow plateaued, indicating that blood volume changes become independent of changes in blood flow. Finally, the effect of different training regimes on changes in muscle blood volume was examined. Subjects were assigned to a training group; two-arm training, one-arm training or a control group. Training did not affect blood volume changes during two-arm exercise. However, during one

  12. Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy as a Forensic Method to Determine the Composition of Inks Used to Print the United States One-cent Blue Benjamin Franklin Postage Stamps of the 19th Century.

    Science.gov (United States)

    Brittain, Harry G

    2016-01-01

    Through the combined use of infrared (IR) absorption spectroscopy and attenuated total reflectance (ATR) sampling, the composition of inks used to print the many different types of one-cent Benjamin Franklin stamps of the 19th century has been established. This information permits a historical evaluation of the formulations used at various times, and also facilitates the differentiation of the various stamps from each other. In two instances, the ink composition permits the unambiguous identification of stamps whose appearance is identical, and which (until now) have only been differentiated through estimates of the degree of hardness or softness of the stamp paper, or through the presence or absence of a watermark in the paper. In these instances, the use of ATR Fourier transform infrared spectroscopy (FT-IR) spectroscopy effectively renders irrelevant two 100-year-old practices of stamp identification. Furthermore, since the use of ATR sampling makes it possible to obtain the spectrum of a stamp still attached to its cover, it is no longer necessary to identify these blue Franklin stamps using their cancellation dates. © The Author(s) 2015.

  13. Infrared spectral reflectances of asteroid surfaces

    Science.gov (United States)

    Larson, H. P.; Veeder, G. J.

    1979-01-01

    This review compares the types of compositional information produced by three complementary techniques used in infrared observations of asteroid surfaces: broadband JHKL photometry, narrow band photometry, and multiplex spectroscopy. The high information content of these infrared observations permits definitive interpretations of asteroid surface compositions in terms of the major meteoritic minerals (olivine, pyroxene, plagioclase feldspar, hydrous silicates, and metallic Ni-Fe). These studies emphasize the individuality of asteroid surface compositions, the inadequacy of simple comparisons with spectra of meteorites, and the need to coordinate spectral measurements of all types to optimize diagnostic capabilities.

  14. Estimating soil zinc concentrations using reflectance spectroscopy

    Science.gov (United States)

    Sun, Weichao; Zhang, Xia

    2017-06-01

    Soil contamination by heavy metals has been an increasingly severe threat to nature environment and human health. Efficiently investigation of contamination status is essential to soil protection and remediation. Visible and near-infrared reflectance spectroscopy (VNIRS) has been regarded as an alternative for monitoring soil contamination by heavy metals. Generally, the entire VNIR spectral bands are employed to estimate heavy metal concentration, which lacks interpretability and requires much calculation. In this study, 74 soil samples were collected from Hunan Province, China and their reflectance spectra were used to estimate zinc (Zn) concentration in soil. Organic matter and clay minerals have strong adsorption for Zn in soil. Spectral bands associated with organic matter and clay minerals were used for estimation with genetic algorithm based partial least square regression (GA-PLSR). The entire VNIR spectral bands, the bands associated with organic matter and the bands associated with clay minerals were incorporated as comparisons. Root mean square error of prediction, residual prediction deviation, and coefficient of determination (R2) for the model developed using combined bands of organic matter and clay minerals were 329.65 mg kg-1, 1.96 and 0.73, which is better than 341.88 mg kg-1, 1.89 and 0.71 for the entire VNIR spectral bands, 492.65 mg kg-1, 1.31 and 0.40 for the organic matter, and 430.26 mg kg-1, 1.50 and 0.54 for the clay minerals. Additionally, in consideration of atmospheric water vapor absorption in field spectra measurement, combined bands of organic matter and absorption around 2200 nm were used for estimation and achieved high prediction accuracy with R2 reached 0.640. The results indicate huge potential of soil reflectance spectroscopy in estimating Zn concentrations in soil.

  15. Cropland Field Monitoring: MMV Page 1 Montana Cropland Enrolled Farm Fields Carbon Sequestration Field Sampling, Measurement, Monitoring, and Verification: Application of Visible-Near Infrared Diffuse Reflectance Spectroscopy (VNIR) and Laser-induced Breakdown Spectroscopy (LIBS)

    Energy Technology Data Exchange (ETDEWEB)

    Lee Spangler; Ross Bricklemyer; David Brown

    2012-03-15

    There is growing need for rapid, accurate, and inexpensive methods to measure, and verify soil organic carbon (SOC) change for national greenhouse gas accounting and the development of a soil carbon trading market. Laboratory based soil characterization typically requires significant soil processing, which is time and resource intensive. This severely limits application for large-region soil characterization. Thus, development of rapid and accurate methods for characterizing soils are needed to map soil properties for precision agriculture applications, improve regional and global soil carbon (C) stock and flux estimates and efficiently map sub-surface metal contamination, among others. The greatest gains for efficient soil characterization will come from collecting soil data in situ, thus minimizing soil sample transportation, processing, and lab-based measurement costs. Visible and near-infrared diffuse reflectance spectroscopy (VisNIR) and laser-induced breakdown spectroscopy (LIBS) are two complementary, yet fundamentally different spectroscopic techniques that have the potential to meet this need. These sensors have the potential to be mounted on a soil penetrometer and deployed for rapid soil profile characterization at field and landscape scales. Details of sensor interaction, efficient data management, and appropriate statistical analysis techniques for model calibrations are first needed. In situ or on-the-go VisNIR spectroscopy has been proposed as a rapid and inexpensive tool for intensively mapping soil texture and organic carbon (SOC). While lab-based VisNIR has been established as a viable technique for estimating various soil properties, few experiments have compared the predictive accuracy of on-the-go and lab-based VisNIR. Eight north central Montana wheat fields were intensively interrogated using on-the-go and lab-based VisNIR. Lab-based spectral data consistently provided more accurate predictions than on-the-go data. However, neither in situ

  16. Infrared spectroscopy with synchrotron radiation

    International Nuclear Information System (INIS)

    Lagarde, P.

    1978-01-01

    Storage rings are normally used as sources of radiation in the X-ray and the u.v. part of the spectrum. It is shown that, with a specially designed component, a storage ring like ACO at Orsay is a very powerful far-infrared source, whose advantages over classical wide band sources are reviewed. (author)

  17. Far infrared reflectivity study of ceramic superconductors

    International Nuclear Information System (INIS)

    Memon, A.; Khan, M.N.; Al-Dallal, S.; Tanner, D.B.; Porter, C.D.

    1992-01-01

    In this paper, the authors report on a study of the far-infrared reflectivity of mixed rare earths and lanthnides ceramic superconductors RBa 2 Cu 3 O 7 in the normal state. The authors' results show that the strength of the phonon modes is reduced when yttrium is partially replaced by gadolinium and europium. Also the critical temperature of these mixed materials is reduced as indicated by the four probe technique

  18. Nanoscale Infrared Spectroscopy of Biopolymeric Materials

    Science.gov (United States)

    Curtis Marcott; Michael Lo; Kevin Kjoller; Craig Prater; Roshan Shetty; Joseph Jakes; Isao Noda

    2012-01-01

    Atomic Force Microscopy (AFM) and infrared (IR) spectroscopy have been combined in a single instrument capable of producing 100 nm spatial resolution IR spectra and images. This new capability enables the spectroscopic characterization of biomaterial domains at levels not previously possible. A tunable IR laser source generating pulses on the order of 10 ns was used...

  19. Near Infrared Spectroscopy Systems for Tissue Oximetry

    DEFF Research Database (Denmark)

    Petersen, Søren Dahl

    for other medical applications. The tissue oximeters are realised by incorporation of pn-diodes into the silicon in order to form arrays of infrared detectors. These arrays can then be used for spatially resolved spectroscopy measurements, with the targeted end user being prematurely born infant children...

  20. Infrared spectroscopy of ionic clusters

    International Nuclear Information System (INIS)

    Price, J.M.

    1990-11-01

    This thesis describes new experiments wherein the infrared vibrational predissociation spectra of a number of mass-selected ionic cluster systems have been obtained and analyzed in the 2600 to 4000 cm -1 region. The species studied include: the hydrated hydronium ions, H 3 O + (H 2 O) 3 -10 , ammoniated ammonium ions, NH 4 + (NH 3 ) 1 -10 and cluster ions involving both water and ammonia around an ammonium ion core, (mixed clusters) NH 4 + (NH 3 ) n (H 2 O) m (n+m=4). In each case, the spectra reveal well resolved structures that can be assigned to transitions arising from the vibrational motions of both the ion core of the clusters and the surrounding neutral solvent molecules. 154 refs., 19 figs., 8 tabs

  1. Infrared spectroscopy of ionic clusters

    Energy Technology Data Exchange (ETDEWEB)

    Price, J.M. (California Univ., Berkeley, CA (USA). Dept. of Chemistry Lawrence Berkeley Lab., CA (USA))

    1990-11-01

    This thesis describes new experiments wherein the infrared vibrational predissociation spectra of a number of mass-selected ionic cluster systems have been obtained and analyzed in the 2600 to 4000 cm{sup {minus}1} region. The species studied include: the hydrated hydronium ions, H{sub 3}O{sup +} (H{sub 2}O){sub 3 {minus}10}, ammoniated ammonium ions, NH{sub 4}{sup +}(NH{sub 3}){sub 1 {minus}10} and cluster ions involving both water and ammonia around an ammonium ion core, (mixed clusters) NH{sub 4}{sup +}(NH{sub 3}){sub n}(H{sub 2}O){sub m} (n+m=4). In each case, the spectra reveal well resolved structures that can be assigned to transitions arising from the vibrational motions of both the ion core of the clusters and the surrounding neutral solvent molecules. 154 refs., 19 figs., 8 tabs.

  2. Near-infrared spectroscopy for cocrystal screening

    DEFF Research Database (Denmark)

    Allesø, Morten; Velaga, Sitaram; Alhalaweh, Amjad

    2008-01-01

    Near-infrared (NIR) spectroscopy is a well-established technique for solid-state analysis, providing fast, noninvasive measurements. The use of NIR spectroscopy for polymorph screening and the associated advantages have recently been demonstrated. The objective of this work was to evaluate...... the analytical potential of NIR spectroscopy for cocrystal screening using Raman spectroscopy as a comparative method. Indomethacin was used as the parent molecule, while saccharin and l-aspartic acid were chosen as guest molecules. Molar ratios of 1:1 for each system were subjected to two types of preparative...... retained in a physical mixture with the guest molecule, while liquid-assisted cogrinding did not induce any changes in the crystal lattice. The good chemical peak selectivity of Raman spectroscopy allowed a straightforward interpretation of sample data by analyzing peak positions and comparing to those...

  3. Pigments which reflect infrared radiation from fire

    Science.gov (United States)

    Berdahl, Paul H.

    1998-01-01

    Conventional paints transmit or absorb most of the intense infrared (IR) radiation emitted by fire, causing them to contribute to the spread of fire. The present invention comprises a fire retardant paint additive that reflects the thermal IR radiation emitted by fire in the 1 to 20 micrometer (.mu.m) wavelength range. The important spectral ranges for fire control are typically about 1 to about 8 .mu.m or, for cool smoky fires, about 2 .mu.m to about 16 .mu.m. The improved inventive coatings reflect adverse electromagnetic energy and slow the spread of fire. Specific IR reflective pigments include titanium dioxide (rutile) and red iron oxide pigments with diameters of about 1 .mu.m to about 2 .mu.m and thin leafing aluminum flake pigments.

  4. Infrared spectroscopy by use of synchrotron radiation

    International Nuclear Information System (INIS)

    Nanba, Takao

    1991-01-01

    During five years since the author wrote the paper on the utilization of synchrotron radiation in long wavelength region, it seems to be recognized that in synchrotron radiation, the light from infrared to milli wave can be utilized, and is considerably useful. Recently the research on coherent synchrotron radiation in this region using electron linac has been developed by Tohoku University group, and the high capability of synchrotron radiation as light source is verified. This paper is the report on the infrared spectroscopic research using incoherent synchrotron radiation obtained from the deflection electromagnet part of electron storage rings. Synchrotron radiation is high luminance white light source including from X-ray to micro wave. The example of research that the author carried out at UVSOR is reported, and the perspective in near future is mentioned. Synchrotron radiation as the light source for infrared spectroscopy, the intensity and dimensions of the light source, far infrared region and mid infrared region, far infrared high pressure spectroscopic experiment, and the heightening of luminance of synchrotron radiation as infrared light source are described. (K.I.)

  5. Analysis of various quality attributes of sunflower and soybean plants by near infra-red reflectance spectroscopy: Development and validation calibration models

    Science.gov (United States)

    Sunflower and soybean are summer annuals that can be grown as an alternative to corn and may be particularly useful in organic production systems. Rapid and low cost methods of analyzing plant quality would be helpful for crop management. We developed and validated calibration models for Near-infrar...

  6. Comparing near-infrared conventional diffuse reflectance spectroscopy and hyperspectral imaging for determination of the bulk properties of solid samples by multivariate regression: determination of Mooney viscosity and plasticity indices of natural rubber.

    Science.gov (United States)

    Juliano da Silva, Carlos; Pasquini, Celio

    2015-01-21

    Conventional reflectance spectroscopy (NIRS) and hyperspectral imaging (HI) in the near-infrared region (1000-2500 nm) are evaluated and compared, using, as the case study, the determination of relevant properties related to the quality of natural rubber. Mooney viscosity (MV) and plasticity indices (PI) (PI0 - original plasticity, PI30 - plasticity after accelerated aging, and PRI - the plasticity retention index after accelerated aging) of rubber were determined using multivariate regression models. Two hundred and eighty six samples of rubber were measured using conventional and hyperspectral near-infrared imaging reflectance instruments in the range of 1000-2500 nm. The sample set was split into regression (n = 191) and external validation (n = 95) sub-sets. Three instruments were employed for data acquisition: a line scanning hyperspectral camera and two conventional FT-NIR spectrometers. Sample heterogeneity was evaluated using hyperspectral images obtained with a resolution of 150 × 150 μm and principal component analysis. The probed sample area (5 cm(2); 24,000 pixels) to achieve representativeness was found to be equivalent to the average of 6 spectra for a 1 cm diameter probing circular window of one FT-NIR instrument. The other spectrophotometer can probe the whole sample in only one measurement. The results show that the rubber properties can be determined with very similar accuracy and precision by Partial Least Square (PLS) regression models regardless of whether HI-NIR or conventional FT-NIR produce the spectral datasets. The best Root Mean Square Errors of Prediction (RMSEPs) of external validation for MV, PI0, PI30, and PRI were 4.3, 1.8, 3.4, and 5.3%, respectively. Though the quantitative results provided by the three instruments can be considered equivalent, the hyperspectral imaging instrument presents a number of advantages, being about 6 times faster than conventional bulk spectrometers, producing robust spectral data by ensuring sample

  7. Femtosecond infrared spectroscopy: study, development and applications

    International Nuclear Information System (INIS)

    Bonvalet, Adeline

    1997-01-01

    This work has been devoted to the development and the applications of a new technique of infrared (5-20 μm) spectroscopy allowing a temporal resolution of 100 fs. This technique relies on a source of ultrashort infrared pulses obtained by frequency mixing in a nonlinear material. In particular, the optical rectification of 12-fs visible pulses in gallium arsenide has allowed us to obtain 40-fs infrared pulses with a spectrum extending from 5 pm up to 15 μm. Spectral resolution has been achieved by Fourier transform spectroscopy, using a novel device we have called Diffracting FTIR. These developments allow to study inter-subband transitions in quantum-well structures. The inter-subband relaxation time has been measured by a pump-probe experiment, in which the sample was excited with a visible pulse, and the variations of inter-subband absorption probed with an infrared pulse. Besides, we have developed a method of coherent emission spectroscopy allowing to monitor the electric field emitted by coherent charge oscillations in quantum wells. The decay of the oscillations due to the loss of coherence between excited levels yields a direct measurement of the dephasing time between these levels. Other applications include biological macromolecules like reaction centers of photosynthetic bacteria. We have shown that we were able to monitor variations of infrared absorption of about 10 -4 optical densities with a temporal resolution of 100 fs. This would constitute a relevant tool to study the role of molecular vibrations during the primary steps of biological processes. (author) [fr

  8. Development of a method for the determination of caffeine anhydrate in various designed intact tablets [correction of tables] by near-infrared spectroscopy: a comparison between reflectance and transmittance technique.

    Science.gov (United States)

    Ito, Masatomo; Suzuki, Tatsuya; Yada, Shuichi; Kusai, Akira; Nakagami, Hiroaki; Yonemochi, Etsuo; Terada, Katsuhide

    2008-08-05

    Using near-infrared (NIR) spectroscopy, an assay method which is not affected by such elements of tablet design as thickness, shape, embossing and scored line was developed. Tablets containing caffeine anhydrate were prepared by direct compression at various compression force levels using different shaped punches. NIR spectra were obtained from these intact tablets using the reflectance and transmittance techniques. A reference assay was performed by high-performance liquid chromatography (HPLC). Calibration models were generated by the partial least-squares (PLS) regression. Changes in the tablet thickness, shape, embossing and scored line caused NIR spectral changes in different ways, depending on the technique used. As a result, noticeable errors in drug content prediction occurred using calibration models generated according to the conventional method. On the other hand, when the various tablet design elements which caused the NIR spectral changes were included in the model, the prediction of the drug content in the tablets was scarcely affected by those elements when using either of the techniques. A comparison of these techniques resulted in higher predictability under the tablet design variations using the transmittance technique with preferable linearity and accuracy. This is probably attributed to the transmittance spectra which sensitively reflect the differences in tablet thickness or shape as a result of obtaining information inside the tablets.

  9. Infrared spectroscopy of some organocobalt (III) compounds

    International Nuclear Information System (INIS)

    Benedetti, A.V.; Mauro, A.E.

    1982-01-01

    The compounds [MeCo(DH) 2 py], [MeCo(DH) 2 H 2 O] (M = methyl; DH = dimethyl-glyoxymate; py = pyridine) and others of general formulae [Co(L)(H 2 O) 2 ] ClO 4 , where L = SALOPHEN = bis (salicylaldehyde)-o-phenylenediimine; SALCN = 1,2-bis (salicylaldehyde) cyclohexylenediimine; SALEN = bis (salicylaldehyde) ethylenediimine; BAE = bis (acetylacetone)-ethylenediimine were synthesized and studied by infrared spectroscopy. The frequencies observed have been assigned to specific group vibrations. (Author) [pt

  10. Application of Attenuated Total Reflectance-Fourier Transformed Infrared (ATR-FTIR) Spectroscopy To Determine the Chlorogenic Acid Isomer Profile and Antioxidant Capacity of Coffee Beans.

    Science.gov (United States)

    Liang, Ningjian; Lu, Xiaonan; Hu, Yaxi; Kitts, David D

    2016-01-27

    The chlorogenic acid isomer profile and antioxidant activity of both green and roasted coffee beans are reported herein using ATR-FTIR spectroscopy combined with chemometric analyses. High-performance liquid chromatography (HPLC) quantified different chlorogenic acid isomer contents for reference, whereas ORAC, ABTS, and DPPH were used to determine the antioxidant activity of the same coffee bean extracts. FTIR spectral data and reference data of 42 coffee bean samples were processed to build optimized PLSR models, and 18 samples were used for external validation of constructed PLSR models. In total, six PLSR models were constructed for six chlorogenic acid isomers to predict content, with three PLSR models constructed to forecast the free radical scavenging activities, obtained using different chemical assays. In conclusion, FTIR spectroscopy, coupled with PLSR, serves as a reliable, nondestructive, and rapid analytical method to quantify chlorogenic acids and to assess different free radical-scavenging capacities in coffee beans.

  11. Determinação não destrutiva do nitrogênio total em plantas por espectroscopia de reflectância difusa no infravermelho próximo Non-destructive determination of total nitrogen in plants by diffuse reflectance near infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Kássio M. G. Lima

    2008-01-01

    Full Text Available Diffuse reflectance near-infrared (DR-NIR spectroscopy associated with partial least squares (PLS multivariate calibration is proposed for a direct, non-destructive, determination of total nitrogen in wheat leaves. The procedure was developed for an Analytical Instrumental Analysis course, carried out at the Institute of Chemistry of the State University of Campinas. The DR-NIR results are in good agreement with those obtained by the Kjeldhal standard procedure, with a relative error of less than ± 3% and the method may be used for teaching purposes as well as for routine analysis.

  12. Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy as an Analytical Method to Investigate the Secondary Structure of a Model Protein Embedded in Solid Lipid Matrices.

    Science.gov (United States)

    Zeeshan, Farrukh; Tabbassum, Misbah; Jorgensen, Lene; Medlicott, Natalie J

    2018-02-01

    Protein drugs may encounter conformational perturbations during the formulation processing of lipid-based solid dosage forms. In aqueous protein solutions, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can investigate these conformational changes following the subtraction of spectral interference of solvent with protein amide I bands. However, in solid dosage forms, the possible spectral contribution of lipid carriers to protein amide I band may be an obstacle to determine conformational alterations. The objective of this study was to develop an ATR FT-IR spectroscopic method for the analysis of protein secondary structure embedded in solid lipid matrices. Bovine serum albumin (BSA) was chosen as a model protein, while Precirol AT05 (glycerol palmitostearate, melting point 58 ℃) was employed as the model lipid matrix. Bovine serum albumin was incorporated into lipid using physical mixing, melting and mixing, or wet granulation mixing methods. Attenuated total reflection FT-IR spectroscopy and size exclusion chromatography (SEC) were performed for the analysis of BSA secondary structure and its dissolution in aqueous media, respectively. The results showed significant interference of Precirol ATO5 with BSA amide I band which was subtracted up to 90% w/w lipid content to analyze BSA secondary structure. In addition, ATR FT-IR spectroscopy also detected thermally denatured BSA solid alone and in the presence of lipid matrix indicating its suitability for the detection of denatured protein solids in lipid matrices. Despite being in the solid state, conformational changes occurred to BSA upon incorporation into solid lipid matrices. However, the extent of these conformational alterations was found to be dependent on the mixing method employed as indicated by area overlap calculations. For instance, the melting and mixing method imparted negligible effect on BSA secondary structure, whereas the wet granulation mixing method promoted

  13. Fourier transform infrared spectroscopy in physics laboratory courses

    International Nuclear Information System (INIS)

    Möllmann, K-P; Vollmer, M

    2013-01-01

    Infrared spectrometry is one of the most important tools in the field of spectroscopic analysis. This is due to the high information content of spectra in the so-called spectroscopic fingerprint region, which enables measurement not only of gases, but also of liquids and solids. Today, infrared spectroscopy is almost completely dominated by Fourier transform infrared (FTIR) spectroscopy. FTIR spectroscopy is able to detect minute quantities in the ppm and ppb ranges, and the respective analyses are now standard tools in science as well as industry. Therefore FTIR spectroscopy should be taught within the standard curriculum at university to physicists and engineers. Here we present respective undergraduate laboratory experiments designed for students at the end of their third year. Experiments deal first with understanding the spectrometer and second with recording and analysing spectra. On the one hand, transmission spectra of gases are treated which relate to environmental analytics (being probably the most prominent and well-known examples), and on the other hand, the focus is on the transmission and reflection spectra of solids. In particular, silicon wafers are studied—as is regularly done in the microelectronics industry—in order to characterize their thickness, oxygen content and phonon modes. (paper)

  14. Using reflectance spectroscopy to predict beef tenderness.

    Science.gov (United States)

    Bowling, M B; Vote, D J; Belk, K E; Scanga, J A; Tatum, J D; Smith, G C

    2009-05-01

    A study was conducted to determine if reflectance measurements made in the near-infrared region of the spectrum were additive to reflectance measurements made in the visible region of the spectrum for predicting Warner-Bratzler shear force (WBSF) values. Eighty seven strip loins were collected following fabrication over 3d at a commercial beef processing facility from heifer carcasses with Slight or Traces marbling scores. Spectroscopic measurements were made at approximately 50h postmortem using a Hunter-Lab UltraScan. Subsequently, all strip loins were aged for 14d, cooked to an internal temperature of 70°C, and sheared to obtain WBSF values. Reflectance measurements obtained in the near-infrared region of the spectrum were correlated with WBSF values, however, these measurements were not additive to the predictive ability of reflectance measurements (R(2) values did not differ) made in the visible portion of the spectrum when the use of broad-band wavelength filters were simulated. It was therefore determined, that both the visible and near-infrared spectra measure reflectance and that both methods are acceptable methods of tenderness prediction.

  15. A spectroelectrochemical cell for ultrafast two-dimensional infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    El Khoury, Youssef; Van Wilderen, Luuk J. G. W.; Vogt, Tim; Winter, Ernst; Bredenbeck, Jens, E-mail: bredenbeck@biophysik.uni-frankfurt.org, E-mail: bredenbeck@biophysik.uni-frankfurt.de [Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt (Germany)

    2015-08-15

    A spectroelectrochemical cell has been designed to combine electrochemistry and ultrafast two-dimensional infrared (2D-IR) spectroscopy, which is a powerful tool to extract structure and dynamics information on the femtosecond to picosecond time scale. Our design is based on a gold mirror with the dual role of performing electrochemistry and reflecting IR light. To provide the high optical surface quality required for laser spectroscopy, the gold surface is made by electron beam evaporation on a glass substrate. Electrochemical cycling facilitates in situ collection of ultrafast dynamics of redox-active molecules by means of 2D-IR. The IR beams are operated in reflection mode so that they travel twice through the sample, i.e., the signal size is doubled. This methodology is optimal for small sample volumes and successfully tested with the ferricyanide/ferrocyanide redox system of which the corresponding electrochemically induced 2D-IR difference spectrum is reported.

  16. A spectroelectrochemical cell for ultrafast two-dimensional infrared spectroscopy

    International Nuclear Information System (INIS)

    El Khoury, Youssef; Van Wilderen, Luuk J. G. W.; Vogt, Tim; Winter, Ernst; Bredenbeck, Jens

    2015-01-01

    A spectroelectrochemical cell has been designed to combine electrochemistry and ultrafast two-dimensional infrared (2D-IR) spectroscopy, which is a powerful tool to extract structure and dynamics information on the femtosecond to picosecond time scale. Our design is based on a gold mirror with the dual role of performing electrochemistry and reflecting IR light. To provide the high optical surface quality required for laser spectroscopy, the gold surface is made by electron beam evaporation on a glass substrate. Electrochemical cycling facilitates in situ collection of ultrafast dynamics of redox-active molecules by means of 2D-IR. The IR beams are operated in reflection mode so that they travel twice through the sample, i.e., the signal size is doubled. This methodology is optimal for small sample volumes and successfully tested with the ferricyanide/ferrocyanide redox system of which the corresponding electrochemically induced 2D-IR difference spectrum is reported

  17. Quantification of live Lactobacillus acidophilus in mixed populations of live and killed by application of attenuated reflection Fourier transform infrared spectroscopy combined with chemometrics.

    Science.gov (United States)

    Toziou, Peristera-Maria; Barmpalexis, Panagiotis; Boukouvala, Paraskevi; Verghese, Susan; Nikolakakis, Ioannis

    2018-05-30

    Since culture-based methods are costly and time consuming, alternative methods are investigated for the quantification of probiotics in commercial products. In this work ATR- FTIR vibration spectroscopy was applied for the differentiation and quantification of live Lactobacillus (La 5) in mixed populations of live and killed La 5, in the absence and in the presence of enteric polymer Eudragit ® L 100-55. Suspensions of live (La 5_L) and killed in acidic environment bacillus (La 5_K) were prepared and binary mixtures of different percentages were used to grow cell cultures for colony counting and spectral analysis. The increase in the number of colonies with added%La 5_L to the mixture was log-linear (r 2  = 0.926). Differentiation of La 5_L from La 5_K was possible directly from the peak area at 1635 cm -1 (amides of proteins and peptides) and a linear relationship between%La 5_L and peak area in the range 0-95% was obtained. Application of partial least squares regression (PLSR) gave reasonable prediction of%La 5_L (RMSEp = 6.48) in binary mixtures of live and killed La 5 but poor prediction (RMSEp = 11.75) when polymer was added to the La 5 mixture. Application of artificial neural networks (ANNs) improved greatly the predictive ability for%La 5_L both in the absence and in the presence of polymer (RMSEp = 8.11 × 10 -8 for La 5 only mixtures and RMSEp = 8.77 × 10 -8 with added polymer) due to their ability to express in the calibration models more hidden spectral information than PLSR. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Rapid analysis of effluents generated by the dairy industry for fat determination by preconcentration in nylon membranes and attenuated total reflectance infrared spectroscopy measurement.

    Science.gov (United States)

    Moliner Martínez, Y; Muñoz-Ortuño, M; Herráez-Hernández, R; Campíns-Falcó, P

    2014-02-01

    This paper describes a new approach for the determination of fat in the effluents generated by the dairy industry which is based on the retention of fat in nylon membranes and measurement of the absorbances on the membrane surface by ATR-IR spectroscopy. Different options have been evaluated for retaining fat in the membranes using milk samples of different origin and fat content. Based on the results obtained, a method is proposed for the determination of fat in effluents which involves the filtration of 1 mL of the samples through 0.45 µm nylon membranes of 13 mm diameter. The fat content is then determined by measuring the absorbance of band at 1745 cm(-1). The proposed method can be used for the direct estimation of fat at concentrations in the 2-12 mg/L interval with adequate reproducibility. The intraday precision, expressed as coefficients of variation CVs, were ≤ 11%, whereas the interday CVs were ≤ 20%. The method shows a good tolerance towards conditions typically found in the effluents generated by the dairy industry. The most relevant features of the proposed method are simplicity and speed as the samples can be characterized in a few minutes. Sample preparation does not involve either additional instrumentation (such as pumps or vacuum equipment) or organic solvents or other chemicals. Therefore, the proposed method can be considered a rapid, simple and cost-effective alternative to gravimetric methods for controlling fat content in these effluents during production or cleaning processes. © 2013 Published by Elsevier B.V.

  19. Coherent atomic and molecular spectroscopy in the far infrared

    International Nuclear Information System (INIS)

    Inguscio, M.

    1988-01-01

    Recent advances in far infrared spectroscopy of atoms (fine structure transitions) and molecules (rotational transitions) are reviewed. Results obtained by means of Laser Magnetic Resonance, using fixed frequency lasers, and Tunable Far Infrared spectrometers are illustrated. The importance of far infrared spectroscopy for several fields, including astrophysics, atmospheric physics, atomic structure and metology, is discussed. (orig.)

  20. Reflectance spectroscopy and asteroid surface mineralogy

    International Nuclear Information System (INIS)

    Gaffey, M.J.; Bell, J.F.; Cruikshank, D.P.

    1989-01-01

    Information available from reflectance spectroscopy on the surface mineralogy of asteroids is discussed. Current spectral interpretive procedures used in the investigations of asteroid mineralogy are described. Present understanding of the nature and history of asteroids is discussed together with some still unresolved issues such as the source of ordinary chondrites. 100 refs

  1. Fourier transform infrared spectroscopy of peptides.

    Science.gov (United States)

    Bakshi, Kunal; Liyanage, Mangala R; Volkin, David B; Middaugh, C Russell

    2014-01-01

    Fourier transform infrared (FTIR) spectroscopy provides data that are widely used for secondary structure characterization of peptides. A wide array of available sampling methods permits structural analysis of peptides in diverse environments such as aqueous solution (including optically turbid media), powders, detergent micelles, and lipid bilayers. In some cases, side chain vibrations can also be resolved and used for tertiary structure and chemical analysis. Data from several low-resolution spectroscopic techniques, including FTIR, can be combined to generate an empirical phase diagram, an overall picture of peptide structure as a function of environmental conditions that can aid in the global interpretation of large amounts of spectroscopic data.

  2. Development of secondary cell wall in cotton fibers as examined with Fourier transform-infrared spectroscopy

    Science.gov (United States)

    Our presentation will focus on continuing efforts to examine secondary cell wall development in cotton fibers using infrared Spectroscopy. Cotton fibers harvested at 18, 20, 24, 28, 32, 36 and 40 days after flowering were examined using attenuated total reflection Fourier transform-infrared (ATR FT-...

  3. Near infrared spectroscopy of human muscles

    Science.gov (United States)

    Gasbarrone, R.; Currà, A.; Cardillo, A.; Bonifazi, G.; Serranti, S.

    2018-02-01

    Optical spectroscopy is a powerful tool in research and industrial applications. Its properties of being rapid, non-invasive and not destructive make it a promising technique for qualitative as well as quantitative analysis in medicine. Recent advances in materials and fabrication techniques provided portable, performant, sensing spectrometers readily operated by user-friendly cabled or wireless systems. We used such a system to test whether infrared spectroscopy techniques, currently utilized in many areas as primary/secondary raw materials sector, cultural heritage, agricultural/food industry, environmental remote and proximal sensing, pharmaceutical industry, etc., could be applied in living humans to categorize muscles. We acquired muscles infrared spectra in the Vis-SWIR regions (350-2500 nm), utilizing an ASD FieldSpec 4 Standard-Res Spectroradiometer with a spectral sampling capability of 1.4 nm at 350-1000 nm and 1.1 nm at 1001-2500 nm. After a preliminary spectra pre-processing (i.e. signal scattering reduction), Principal Component Analysis (PCA) was applied to identify similar spectral features presence and to realize their further grouping. Partial Least-Squares Discriminant Analysis (PLS-DA) was utilized to implement discrimination/prediction models. We studied 22 healthy subjects (age 25-89 years, 11 females), by acquiring Vis-SWIR spectra from the upper limb muscles (i.e. biceps, a forearm flexor, and triceps, a forearm extensor). Spectroscopy was performed in fixed limb postures (elbow angle approximately 90‡). We found that optical spectroscopy can be applied to study human tissues in vivo. Vis-SWIR spectra acquired from the arm detect muscles, distinguish flexors from extensors.

  4. Infrared spectroscopy of self-assembled monolayer films on silicon

    Science.gov (United States)

    Rowell, N. L.; Tay, Lilin; Boukherroub, R.; Lockwood, D. J.

    2007-07-01

    Infrared vibrational spectroscopy in an attenuated total reflection (ATR) geometry has been employed to investigate the presence of organic thin layers on Si-wafer surfaces. The phenomena have been simulated to show there can be a field enhancement with the presented single-reflection ATR (SR-ATR) approach which is substantially larger than for conventional ATR or specular reflection. In SR-ATR, a discontinuity of the field normal to the film contributes a field enhancement in the lower index thin film causing a two order of magnitude increase in sensitivity. SR-ATR was employed to characterize a single monolayer of undecylenic acid self-assembled on Si(1 1 1) and to investigate a two monolayer system obtained by adding a monolayer of bovine serum albumin protein.

  5. Infrared spectroscopy of mass-selected carbocations

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, Michael A. [Department of Chemistry, University of Georgia, Athens, Georgia 30602 (United States)

    2015-01-22

    Small carbocations are of longstanding interest in astrophysics, but there are few measurements of their infrared spectroscopy in the gas phase at low temperature. There are fewer-still measurements of spectra across the full range of IR frequencies useful to obtain an IR signature of these ions to detect them in space. We have developed a pulsed-discharge supersonic nozzle ion source producing high densities of small carbocations at low temperatures (50–70K). We employ mass-selected photodissociation spectroscopy and the method of rare gas “tagging”, together with new broadly tunable infrared OPO lasers, to obtain IR spectra for a variety of small carbocations including C{sub 2}H{sub 3}{sup +}, C{sub 3}H{sub 3}{sup +}, C{sub 3}H{sub 5}{sup +}, protonated benzene and protonated naphthalene. Spectra in the frequency range of 600–4500 cm{sup −1} provide new IR data for these ions and evidence for the presence of co-existing isomeric structures (e.g., C{sub 3}H{sub 3}{sup +} is present as both cyclopropenyl and propargyl). Protonated naphthalene has sharp bands at 6.2, 7.7 and 8.6 microns matching prominent features in the UIR spectra.

  6. Infrared Spectroscopy as a Chemical Fingerprinting Tool

    Science.gov (United States)

    Huff, Timothy L.

    2003-01-01

    Infrared (IR) spectroscopy is a powerful analytical tool in the chemical fingerprinting of materials. Any sample material that will interact with infrared light produces a spectrum and, although normally associated with organic materials, inorganic compounds may also be infrared active. The technique is rapid, reproducible and usually non-invasive to the sample. That it is non-invasive allows for additional characterization of the original material using other analytical techniques including thermal analysis and RAMAN spectroscopic techniques. With the appropriate accessories, the technique can be used to examine samples in liquid, solid or gas phase. Both aqueous and non-aqueous free-flowing solutions can be analyzed, as can viscous liquids such as heavy oils and greases. Solid samples of varying sizes and shapes may also be examined and with the addition of microscopic IR (microspectroscopy) capabilities, minute materials such as single fibers and threads may be analyzed. With the addition of appropriate software, microspectroscopy can be used for automated discrete point or compositional surface area mapping, with the latter providing a means to record changes in the chemical composition of a material surface over a defined area. Due to the ability to characterize gaseous samples, IR spectroscopy can also be coupled with thermal processes such as thermogravimetric (TG) analyses to provide both thermal and chemical data in a single run. In this configuration, solids (or liquids) heated in a TG analyzer undergo decomposition, with the evolving gases directed into the IR spectrometer. Thus, information is provided on the thermal properties of a material and the order in which its chemical constituents are broken down during incremental heating. Specific examples of these varied applications will be cited, with data interpretation and method limitations further discussed.

  7. Introduction to experimental infrared spectroscopy fundamentals and practical methods

    CERN Document Server

    Tasumi, Mitsuo; Ochiai, Shukichi

    2014-01-01

    Infrared spectroscopy is generally understood to mean the science of spectra relating to infrared radiation, namely electromagnetic waves, in the wavelength region occurring intermediately between visible light and microwaves. Measurements of infrared spectra have been providing useful information, for a variety of scientific research and industrial studies, for over half a century; this is set to continue in the foreseeable future. Introduction to Experimental Infrared Spectroscopy is intended to be a handy guide for those who have no, or limited, experience in infrared spectroscopi

  8. Near Infrared Spectroscopy as a Hemodynamic Monitor in Critical Illness.

    Science.gov (United States)

    Ghanayem, Nancy S; Hoffman, George M

    2016-08-01

    The objectives of this review are to discuss the technology and clinical interpretation of near infrared spectroscopy oximetry and its clinical application in patients with congenital heart disease. MEDLINE and PubMed. Near infrared spectroscopy provides a continuous noninvasive assessment of tissue oxygenation. Over 20 years ago, near infrared spectroscopy was introduced into clinical practice for monitoring cerebral oxygenation during cardiopulmonary bypass in adults. Since that time, the utilization of near infrared spectroscopy has extended into the realm of pediatric cardiac surgery and is increasingly being used in the cardiac ICU to monitor tissue oxygenation perioperatively.

  9. Mid-infrared spectroscopy in skin cancer cell type identification

    Science.gov (United States)

    Kastl, Lena; Kemper, Björn; Lloyd, Gavin R.; Nallala, Jayakrupakar; Stone, Nick; Naranjo, Valery; Penaranda, Francisco; Schnekenburger, Jürgen

    2017-07-01

    Mid infrared spectroscopy samples were developed for the analysis of skin tumor cell types and three dimensional tissue phantoms towards the application of midIR spectroscopy for fast and reliable skin cancer diagnostics.

  10. Functional Near Infrared Spectroscopy: Enabling Routine Functional Brain Imaging.

    Science.gov (United States)

    Yücel, Meryem A; Selb, Juliette J; Huppert, Theodore J; Franceschini, Maria Angela; Boas, David A

    2017-12-01

    Functional Near-Infrared Spectroscopy (fNIRS) maps human brain function by measuring and imaging local changes in hemoglobin concentrations in the brain that arise from the modulation of cerebral blood flow and oxygen metabolism by neural activity. Since its advent over 20 years ago, researchers have exploited and continuously advanced the ability of near infrared light to penetrate through the scalp and skull in order to non-invasively monitor changes in cerebral hemoglobin concentrations that reflect brain activity. We review recent advances in signal processing and hardware that significantly improve the capabilities of fNIRS by reducing the impact of confounding signals to improve statistical robustness of the brain signals and by enhancing the density, spatial coverage, and wearability of measuring devices respectively. We then summarize the application areas that are experiencing rapid growth as fNIRS begins to enable routine functional brain imaging.

  11. Visualizing Infrared (IR) Spectroscopy with Computer Animation

    Science.gov (United States)

    Abrams, Charles B.; Fine, Leonard W.

    1996-01-01

    IR Tutor, an interactive, animated infrared (IR) spectroscopy tutorial has been developed for Macintosh and IBM-compatible computers. Using unique color animation, complicated vibrational modes can be introduced to beginning students. Rules governing the appearance of IR absorption bands become obvious because the vibrational modes can be visualized. Each peak in the IR spectrum is highlighted, and the animation of the corresponding normal mode can be shown. Students can study each spectrum stepwise, or click on any individual peak to see its assignment. Important regions of each spectrum can be expanded and spectra can be overlaid for comparison. An introduction to the theory of IR spectroscopy is included, making the program a complete instructional package. Our own success in using this software for teaching and research in both academic and industrial environments will be described. IR Tutor consists of three sections: (1) The 'Introduction' is a review of basic principles of spectroscopy. (2) 'Theory' begins with the classical model of a simple diatomic molecule and is expanded to include larger molecules by introducing normal modes and group frequencies. (3) 'Interpretation' is the heart of the tutorial. Thirteen IR spectra are analyzed in detail, covering the most important functional groups. This section features color animation of each normal mode, full interactivity, overlay of related spectra, and expansion of important regions. This section can also be used as a reference.

  12. Voyager infrared spectroscopy and radiometry investigation

    Energy Technology Data Exchange (ETDEWEB)

    Hanel, R; Conrath, B; Gautier, D; Gierasch, P; Kumar, S; Kunde, V; Lowman, P; Maguire, W; Pearl, J; Pirraglia, J [National Aeronautics and Space Administration, Greenbelt, Md. (USA). Goddard Space Flight Center

    1977-11-01

    The infrared investigation on Voyager uses two interferometers covering the spectral ranges 60-600 cm/sup -1/ (17-170 ..mu..m) and 1000-7000 cm/sup -1/ (1.4-10 ..mu..m), and a radiometer covering the range 8000-25000 cm/sup -1/ (0.4-1.2 ..mu..m). Two spectral resolutions (approximately 6.5 and 2.0 cm/sup -1/) are available for each of the interferometers. In the middle of the thermal channel (far infrared interferometer) the noise level is equivalent to the signal from a target at 50 K; in the middle of the reflected sunlight channel (near infrared interferometer) the noise level is equivalent to the signal from an object of albedo 0.2 at the distance of Uranus. For planets and satellites with substantial atmospheres, the data will be used to investigate cloud and gas composition (including isotopic ratios), haze scale height, atmospheric vertical thermal structure, local and planetary circulation and dynamics, and planetary energy balance. For satellites with tenuous atmospheres, data will be gathered on surface and atmospheric compositon, surface temperature and thermal properties, local and global phase functions, and surface structure. For Saturn's rings, the composition and radial structure, particle size and thermal characteristics will be investigated. Comparative studies of the planets and their satellite systems will be carried out.

  13. Predicting rapeseed oil content with near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Roberta Rossato

    2013-12-01

    Full Text Available The objective of this work was to establish a calibration equation and to estimate the efficiency of near-infrared reflectance (NIR spectroscopy for evaluating rapeseed oil content in Southern Brazil. Spectral data from 124 half-sib families were correlated with oil contents determined by the chemical method. The accuracy of the equation was verified by coefficient of determination (R² of 0.92, error of calibration (SEC of 0.78, and error of performance (SEP of 1.22. The oil content of ten genotypes, which were not included in the calibration with NIR, was similar to the one obtained by the standard chemical method. NIR spectroscopy is adequate to differentiate oil content of rapeseed genotypes.

  14. Buccal microbiology analyzed by infrared spectroscopy

    Science.gov (United States)

    de Abreu, Geraldo Magno Alves; da Silva, Gislene Rodrigues; Khouri, Sônia; Favero, Priscila Pereira; Raniero, Leandro; Martin, Airton Abrahão

    2012-01-01

    Rapid microbiological identification and characterization are very important in dentistry and medicine. In addition to dental diseases, pathogens are directly linked to cases of endocarditis, premature delivery, low birth weight, and loss of organ transplants. Fourier Transform Infrared Spectroscopy (FTIR) was used to analyze oral pathogens Aggregatibacter actinomycetemcomitans ATCC 29523, Aggregatibacter actinomycetemcomitans-JP2, and Aggregatibacter actinomycetemcomitans which was clinically isolated from the human blood-CI. Significant spectra differences were found among each organism allowing the identification and characterization of each bacterial species. Vibrational modes in the regions of 3500-2800 cm-1, the 1484-1420 cm-1, and 1000-750 cm-1 were used in this differentiation. The identification and classification of each strain were performed by cluster analysis achieving 100% separation of strains. This study demonstrated that FTIR can be used to decrease the identification time, compared to the traditional methods, of fastidious buccal microorganisms associated with the etiology of the manifestation of periodontitis.

  15. Infrared spectroscopy of different phosphates structures.

    Science.gov (United States)

    Jastrzębski, W; Sitarz, M; Rokita, M; Bułat, K

    2011-08-15

    Infrared (IR) spectroscopic studies of mineral and synthetic phosphates have been presented. The interpretation of the spectra has been preceded by the isolated [PO(4)](3-) tetrahedron spectra analyse. The K(3)PO(4) saturated aqueous solution was measured in the special cell for liquids. The obtained IR results have been compared with the theoretical number of IR-active modes. The number and positions of the bands due to P-O vibrations have been established. The phase composition of the phosphates has been determined using XRD and IR spectroscopy methods. The influence of non-tetrahedral cations on the shape of the spectra and the positions of bands has been analysed and the crystalline field splitting effect has been discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Characterization of UO2 by infrared spectroscopy

    International Nuclear Information System (INIS)

    Faeda, Kelly C.M.; Machado, Geraldo C.; Lameiras, Fernando S.

    2011-01-01

    The characterization of nuclear fuel is of great importance to minimize the effects related to burnup and temperature and to achieve stability during in-core operation. The understanding the U-O system and its thermodynamic properties has fundamental importance in nuclear industry. Many physical properties of UO 2±x depend on the ratio O / U, such as the electrical conductivity and thermal properties, as well as the diffusivities of its constituents and solutes. The U-O system presents various oxides such as UO 2±x , U 4 O 9 , U 3 O 8 , and UO 3 . The control of the O/U relation is critical to the manufacturing process of UO 2 . In this work, the infrared spectroscopy was used to identify the presence of phases in UO 2 powder samples that cannot be identified by thermogravimetry and X-ray diffraction. (author)

  17. Infrared and THz spectroscopy of nanostructured dielectrics

    Directory of Open Access Journals (Sweden)

    Jan Petzelt

    2009-09-01

    Full Text Available Results achieved using the infrared/THz spectroscopy of various inhomogeneous dielectrics in the Department of Dielectrics, Institute of Physics, Prague, during the last decade are briefly reviewed. The discussion concerns high-permittivity ceramics with inevitable low-permittivity dead layers along the grain boundaries, relaxor ferroelectrics with highly anisotropic polar nano-regions, classical matrix-type composites, core-shell composites, filled nanoporous glasses, polycrystalline and epitaxial thin films, heterostructures and superlattices on dielectric substrates. The analysis using models based on the effective medium approach is discussed. The importance of depolarizing field and of the percolation of components on the effective ac dielectric response and the excitations contributing to it are emphasized.

  18. High resolution infrared spectroscopy of symbiotic stars

    International Nuclear Information System (INIS)

    Bensammar, S.

    1989-01-01

    We report here very early results of high resolution (5x10 3 - 4x10 4 ) infrared spectroscopy (1 - 2.5 μm) of different symbiotic stars (T CrB, RW Hya, CI Cyg, PU Vul) observed with the Fourier Transform Spectrometer of the 3.60m Canada France Hawaii Telescope. These stars are usually considered as interacting binaries and only little details are known about the nature of their cool component. CO absorption lines are detected for the four stars. Very different profiles of hydrogen Brackett γ and helium 10830 A lines are shown for CI Cyg observed at different phases, while Pu Vul shows very intense emission lines

  19. [Identification of Dendrobium varieties by infrared spectroscopy].

    Science.gov (United States)

    Liu, Fei; Wang, Yuan-Zhong; Yang, Chun-Yan; Jin, Hang

    2014-11-01

    The difference of Dendrobium varieties were analyzed by Fourier transform infrared (FTIR) spectroscopy. The infrared spectra of 206 stems from 30 Dendrobium varieties were obtained, and showed that polysaccharides, especially fiber, were the main components in Dendrobium plants. FTIR combined with Wilks' Lambda stepwise discriminative analysis was used to identify Dendrobium varieties. The effects of spectral range and number of training samples on the discrimination results were also analysed. Two hundred eighty seven variables in the spectral range of 1 800-1 250 cm(-1) were studied, and showed that the return discrimination is 100% correct when the training samples number of each species was 2, 3, 4, 5, and 6, respectively, whereas for the remaining samples the correct rates of identification were equal to 79.4%, 91.3%, 93.0%, 98.2%, and 100%, respectively. The same discriminative analyses on five different training samples in the spectral range of 1 800-1 500, 1 500-1 250, 1 250-600, 1 250-950 and 950-650 cm(-1) were compared, which showed that the variables in the range of 1 800-1 250, 1 800-1 500 and 950-600 cm(-1) were more suitable for variety identification, and one can obtain the satisfactory result for discriminative analysis when the training sample is more than 3. Our results indicate that FTIR combined with stepwise discriminative analysis is an effective way to distinguish different Dendrobium varieties.

  20. Transmission versus reflectance spectroscopy for quantitation

    Science.gov (United States)

    Gardner, Craig M.

    2018-01-01

    The objective of this work was to compare the accuracy of analyte concentration estimation when using transmission versus diffuse reflectance spectroscopy of a scattering medium. Monte Carlo ray tracing of light through the medium was used in conjunction with pure component absorption spectra and Beer-Lambert absorption along each ray's pathlength to generate matched sets of pseudoabsorbance spectra, containing water and six analytes present in skin. PLS regression models revealed an improvement in accuracy when using transmission compared to reflectance for a range of medium thicknesses and instrument noise levels. An analytical expression revealed the source of the accuracy degradation with reflectance was due both to the reduced collection efficiency for a fixed instrument etendue and to the broad pathlength distribution that detected light travels in the medium before exiting from the incident side.

  1. Influence of earlobe thickness on near infrared spectroscopy

    Science.gov (United States)

    Jiang, Jingying; Wang, Tianpei; Li, Si; Li, Lin; Liu, Jiajia; Xu, Kexin

    2017-03-01

    Near-infrared spectroscopy has been recognized as a potential technology for noninvasive blood glucose sensing. However, the detected spectral signal is unstable mainly because of (1) the weak light absorption of glucose itself within NIR range, (2) the influence of temperature and individual differences of biotissue. Our previous results demonstrated that the synergistic effect of both transmittance and reflectance could enhance the strength of the detection signal. In this talk, we design a set of experiments to analyze the effect of earlobe thickness on Near Infrared spectroscopic measurement by using home-made optical fiber probe within the wavelength of 1000-1600nm. Firstly, we made a MC simulation of single-layer skin model and five-layer skin model to get the diffused transmittance spectra and diffused reflectance spectra under different optaical path lengths. And then we obtain the spectra of the earlobes from different volunteers by the same way. The experimental results showed that with the increase of the thickness,the light intensity of diffused transmittance decreases, and the light intensity of diffused reflectance remaines substantially unchanged.

  2. Characterizing aeroallergens by infrared spectroscopy of fungal spores and pollen.

    Directory of Open Access Journals (Sweden)

    Boris Zimmermann

    Full Text Available Fungal spores and plant pollen cause respiratory diseases in susceptible individuals, such as asthma, allergic rhinitis and hypersensitivity pneumonitis. Aeroallergen monitoring networks are an important part of treatment strategies, but unfortunately traditional analysis is time consuming and expensive. We have explored the use of infrared spectroscopy of pollen and spores for an inexpensive and rapid characterization of aeroallergens.The study is based on measurement of spore and pollen samples by single reflectance attenuated total reflectance Fourier transform infrared spectroscopy (SR-ATR FTIR. The experimental set includes 71 spore (Basidiomycota and 121 pollen (Pinales, Fagales and Poales samples. Along with fresh basidiospores, the study has been conducted on the archived samples collected within the last 50 years.The spectroscopic-based methodology enables clear spectral differentiation between pollen and spores, as well as the separation of confamiliar and congeneric species. In addition, the analysis of the scattering signals inherent in the infrared spectra indicates that the FTIR methodology offers indirect estimation of morphology of pollen and spores. The analysis of fresh and archived spores shows that chemical composition of spores is well preserved even after decades of storage, including the characteristic taxonomy-related signals. Therefore, biochemical analysis of fungal spores by FTIR could provide economical, reliable and timely methodologies for improving fungal taxonomy, as well as for fungal identification and monitoring. This proof of principle study shows the potential for using FTIR as a rapid tool in aeroallergen studies. In addition, the presented method is ready to be immediately implemented in biological and ecological studies for direct measurement of pollen and spores from flowers and sporocarps.

  3. Comparing predictive ability of laser-induced breakdown spectroscopy to visible near-infrared spectroscopy for soil property determination

    DEFF Research Database (Denmark)

    Knadel, Maria; Gislum, René; Hermansen, Cecilie

    2017-01-01

    Soil organic carbon (SOC) and particle size fractions have a practical value for agronomy and the environment. Thus, alternative techniques to replace the expensive conventional analyses of soil are needed. Visible near-infrared reflectance spectroscopy (viseNIRS) has already shown potential...

  4. Indirect absorption spectroscopy using quantum cascade lasers: mid-infrared refractometry and photothermal spectroscopy.

    Science.gov (United States)

    Pfeifer, Marcel; Ruf, Alexander; Fischer, Peer

    2013-11-04

    We record vibrational spectra with two indirect schemes that depend on the real part of the index of refraction: mid-infrared refractometry and photothermal spectroscopy. In the former, a quantum cascade laser (QCL) spot is imaged to determine the angles of total internal reflection, which yields the absorption line via a beam profile analysis. In the photothermal measurements, a tunable QCL excites vibrational resonances of a molecular monolayer, which heats the surrounding medium and changes its refractive index. This is observed with a probe laser in the visible. Sub-monolayer sensitivities are demonstrated.

  5. Adaptive infrared-reflecting systems inspired by cephalopods

    Science.gov (United States)

    Xu, Chengyi; Stiubianu, George T.; Gorodetsky, Alon A.

    2018-03-01

    Materials and systems that statically reflect radiation in the infrared region of the electromagnetic spectrum underpin the performance of many entrenched technologies, including building insulation, energy-conserving windows, spacecraft components, electronics shielding, container packaging, protective clothing, and camouflage platforms. The development of their adaptive variants, in which the infrared-reflecting properties dynamically change in response to external stimuli, has emerged as an important unmet scientific challenge. By drawing inspiration from cephalopod skin, we developed adaptive infrared-reflecting platforms that feature a simple actuation mechanism, low working temperature, tunable spectral range, weak angular dependence, fast response, stability to repeated cycling, amenability to patterning and multiplexing, autonomous operation, robust mechanical properties, and straightforward manufacturability. Our findings may open opportunities for infrared camouflage and other technologies that regulate infrared radiation.

  6. Infrared spectroscopy of anionic hydrated fluorobenzenes

    International Nuclear Information System (INIS)

    Schneider, Holger; Vogelhuber, Kristen M.; Weber, J. Mathias

    2007-01-01

    We investigate the structural motifs of anionic hydrated fluorobenzenes by infrared photodissociation spectroscopy and density functional theory. Our calculations show that all fluorobenzene anions under investigation are strongly distorted from the neutral planar molecular geometries. In the anions, different F atoms are no longer equivalent, providing structurally different binding sites for water molecules and giving rise to a multitude of low-lying isomers. The absorption bands for hexa- and pentafluorobenzene show that only one isomer for the respective monohydrate complexes is populated in our experiment. For C 6 F 6 - ·H 2 O, we can assign these bands to an isomer where water forms a weak double ionic hydrogen bond with two F atoms in the ion, in accord with the results of Bowen et al. [J. Chem. Phys. 127, 014312 (2007), following paper.] The spectroscopic motif of the binary complexes changes slightly with decreasing fluorination of the aromatic anion. For dihydrated hexafluorobenzene anions, several isomers are populated in our experiments, some of which may be due to hydrogen bonding between water molecules

  7. Fourier Transform Infrared Spectroscopy and Photoacoustic Spectroscopy for Saliva Analysis.

    Science.gov (United States)

    Mikkonen, Jopi J W; Raittila, Jussi; Rieppo, Lassi; Lappalainen, Reijo; Kullaa, Arja M; Myllymaa, Sami

    2016-09-01

    Saliva provides a valuable tool for assessing oral and systemic diseases, but concentrations of salivary components are very small, calling the need for precise analysis methods. In this work, Fourier transform infrared (FT-IR) spectroscopy using transmission and photoacoustic (PA) modes were compared for quantitative analysis of saliva. The performance of these techniques was compared with a calibration series. The linearity of spectrum output was verified by using albumin-thiocyanate (SCN(-)) solution at different SCN(-) concentrations. Saliva samples used as a comparison were obtained from healthy subjects. Saliva droplets of 15 µL were applied on the silicon sample substrate, 6 drops for each specimen, and dried at 37 ℃ overnight. The measurements were carried out using an FT-IR spectrometer in conjunction with an accessory unit for PA measurements. The findings with both transmission and PA modes mirror each other. The major bands presented were 1500-1750 cm(-1) for proteins and 1050-1200 cm(-1) for carbohydrates. In addition, the distinct spectral band at 2050 cm(-1) derives from SCN(-) anions, which is converted by salivary peroxidases to hypothiocyanate (OSCN(-)). The correlation between the spectroscopic data with SCN(-) concentration (r > 0.990 for transmission and r = 0.967 for PA mode) was found to be significant (P < 0.01), thus promising to be utilized in future applications. © The Author(s) 2016.

  8. Tunable infrared reflectance by phonon modulation

    Science.gov (United States)

    Ihlefeld, Jon F.; Sinclair, Michael B.; Beechem, III, Thomas E.

    2018-03-06

    The present invention pertains to the use of mobile coherent interfaces in a ferroelectric material to interact with optical phonons and, ultimately, to affect the material's optical properties. In altering the optical phonon properties, the optical properties of the ferroelectric material in the spectral range near-to the phonon mode frequency can dramatically change. This can result in a facile means to change to the optical response of the ferroelectric material in the infrared.

  9. Tunable infrared reflectance by phonon modulation

    Energy Technology Data Exchange (ETDEWEB)

    Ihlefeld, Jon F.; Sinclair, Michael B.; Beechem, III, Thomas E.

    2018-03-06

    The present invention pertains to the use of mobile coherent interfaces in a ferroelectric material to interact with optical phonons and, ultimately, to affect the material's optical properties. In altering the optical phonon properties, the optical properties of the ferroelectric material in the spectral range near-to the phonon mode frequency can dramatically change. This can result in a facile means to change to the optical response of the ferroelectric material in the infrared.

  10. Optical Reflection Spectroscopy of GEO Objects

    Science.gov (United States)

    Seitzer, Patrick; Cardona, Tammaso; Lederer, Susan M.; Cowardin, Heather; Abercromby, Kira J.; Barker, Edwin S.; Bedard, Donald

    2013-01-01

    We report on optical reflection spectroscopy of geosynchronous (GEO) objects in the US Space Surveillance Network (SSN) catalog. These observations were obtained using imaging spectrographs on the 6.5-m Magellan telescopes at the Las Campanas Observatory in Chile. Our goal is to determine the composition of these objects by comparing these spectral observations with ground-based laboratory measurements of spacecraft materials. The observations are all low resolution (1 nm after smoothing) obtained through a 5 arcsecond wide slit and using a grism as the dispersing element. The spectral range covered was from 450 nm to 800 nm. All spectra were flux calibrated using observations of standard stars with the exact same instrumental setup. An effort was made to obtain all observations within a limited range of topocentric phase angle, although the solar incident angle is unknown due to the lack of any knowledge of the attitude of the observed surface at the time of observation.

  11. Infrared diode laser spectroscopy of lithium hydride

    International Nuclear Information System (INIS)

    Yamada, C.; Hirota, E.

    1988-01-01

    The fundamental and hot bands of the vibration--rotation transitions of 6 LiH, 7 LiH, 6 LiD, and 7 LiD were observed by infrared diode laser spectroscopy at Doppler-limited resolution. Lithium hydride molecules were produced by the reaction of the Li vapor with hydrogen at elevated temperatures. Some 40 transitions were observed and, after combined with submillimeter-wave spectra reported by G. M. Plummer et al. [J. Chem. Phys. 81, 4893 (1984)], were analyzed to yield Dunham-type constants with accuracies more than an order of magnitude higher than those published in the literature. It was clearly demonstrated that the Born--Oppenheimer approximation did not hold, and some parameters representing the breakdown were evaluated. The Born--Oppenheimer internuclear distance r/sup BO//sub e/ was derived to be 1.594 914 26 (59) A, where a new value of Planck's constant recommended by CODATA was employed. The relative intensity of absorption lines was measured to determine the ratio of the permanent dipole moment to its first derivative with respect to the internuclear distance: μ/sub e/ [(partialμpartialr)/sub e/ r/sub e/ ] = 1.743(86). The pressure broadening parameter Δν/sub p/ P was determined to be 6.40 (22) MHzTorr by measuring the linewidth dependence on the pressure of hydrogen, which was about four times larger than the value for the dipole--quadrupole interaction estimated by Kiefer and Bushkovitch's theory

  12. Ultrafast stimulated Raman spectroscopy in the near-infrared region

    International Nuclear Information System (INIS)

    Takaya, Tomohisa

    2016-01-01

    A number of electronic transitions in the near-infrared wavelength region are associated with migration or delocalization of electrons in large molecules or molecular systems. Time-resolved near-infrared Raman spectroscopy will be a powerful tool for investigating the structural dynamic of samples with delocalized electrons. However, the sensitivity of near-infrared spontaneous Raman spectrometers is significantly low due to an extremely small probability of Raman scattering and a low sensitivity of near-infrared detectors. Nonlinear Raman spectroscopy is one of the techniques that can overcome the sensitivity problems and enable us to obtain time-resolved Raman spectra in resonance with near-IR transitions. In this article, the author introduces recent progress of ultrafast time-resolved near-infrared stimulated Raman spectroscopy. Optical setup, spectral and temporal resolution, and applications of the spectrometer are described. (author)

  13. Quantum cascade laser infrared spectroscopy of single cancer cells

    KAUST Repository

    Patel, Imran

    2017-03-27

    Quantum cascade laser infrared spectroscopy is a next generation novel imaging technique allowing high resolution spectral imaging of cells. We show after spectral pre-processing, identification of different cancer cell populations within minutes.

  14. Cerebral near infrared spectroscopy oximetry in extremely preterm infants

    DEFF Research Database (Denmark)

    Hyttel-Sorensen, Simon; Pellicer, Adelina; Alderliesten, Thomas

    2015-01-01

    OBJECTIVE: To determine if it is possible to stabilise the cerebral oxygenation of extremely preterm infants monitored by cerebral near infrared spectroscopy (NIRS) oximetry. DESIGN: Phase II randomised, single blinded, parallel clinical trial. SETTING: Eight tertiary neonatal intensive care unit...

  15. Quantum cascade laser infrared spectroscopy of single cancer cells

    KAUST Repository

    Patel, Imran; Rajamanickam, Vijayakumar Palanisamy; Bertoncini, Andrea; Pagliari, Francesca; Tirinato, Luca; Laptenok, Sergey P.; Liberale, Carlo

    2017-01-01

    Quantum cascade laser infrared spectroscopy is a next generation novel imaging technique allowing high resolution spectral imaging of cells. We show after spectral pre-processing, identification of different cancer cell populations within minutes.

  16. Analysis of contaminants on electronic components by reflectance FTIR spectroscopy

    International Nuclear Information System (INIS)

    Griffith, G.W.

    1982-09-01

    The analysis of electronic component contaminants by infrared spectroscopy is often a difficult process. Most of the contaminants are very small, which necessitates the use of microsampling techniques. Beam condensers will provide the required sensitivity but most require that the sample be removed from the substrate before analysis. Since it can be difficult and time consuming, it is usually an undesirable approach. Micro ATR work can also be exasperating, due to the difficulty of positioning the sample at the correct place under the ATR plate in order to record a spectrum. This paper describes a modified reflection beam condensor which has been adapted to a Nicolet 7199 FTIR. The sample beam is directed onto the sample surface and reflected from the substrate back to the detector. A micropositioning XYZ stage and a close-focusing telescope are used to position the contaminant directly under the infrared beam. It is possible to analyze contaminants on 1 mm wide leads surrounded by an epoxy matrix using this device. Typical spectra of contaminants found on small circuit boards are included

  17. Fast infrared spectroscopy in supercritical fluids

    International Nuclear Information System (INIS)

    Sun, X.

    2000-05-01

    Chapter 1: Introduction. A brief introduction to supercritical fluids is given, illustrating why supercritical fluids are unique solvents and why there is a wide application of supercritical fluids in industry and laboratories. Potential ways for solvation in supercritical fluids to affect reactivity are briefly reviewed. A general introduction to the photochemistry of organometallic complexes is also given. Chapter 2: Time resolved vibrational spectroscopy. Time resolved resonance Raman is introduced and compared with Time-resolved infrared spectroscopy (TRIR). The different approaches of TRIR, including microsecond, nanosecond, and ultrafast (picosecond and femtosecond) systems are discussed. The advantages and disadvantages of these systems are also compared. The TRIR apparatus using an IR diode laser used for work in this thesis are described in detail. Experimental procedures for supercritical fluid TRIR experiments are described with emphasis on handling the IR cell for supercritical fluids and preparation of supercritical fluid solutions. Chapter 3: Photochemistry of group VIB hexacarbonyl compounds in supercritical noble gases and CO 2 solutions. A systematic TRIR study of the photolysis of M(CO) 6 in supercritical Ar, Kr, Xe, and CO 2 and the observation of M(CO) 5 L (M = Cr, Mo, and W; L = Ar (W only), Kr, Xe, and CO 2 ) is described. The second-order rate constants for the reaction of M(CO) 5 L with CO have been evaluated and the reactivity for each metal is Kr > Xe ∼ CO 2 . For M(CO) 5 Kr, M(CO) 5 Xe, or M(CO) 5 (CO 2 ), the reactivity is Cr ∼ Mo > W. In supercritical Kr doped with either Xe or CO 2 , the M(CO) 5 moiety interacts with Xe or CO 2 in preference to Kr. The effect of solvent density on the rate of the reaction of W(CO) 5 (CO 2 ) with CO has been investigated. The reaction of W(CO) 5 (CO 2 ) with CO in scCO 2 is predominantly a dissociative process. The activation energies for the reaction of W(CO) 5 Xe and W(CO) 5 (CO 2 ) with CO and

  18. Reflectance spectroscopy of organic compounds: 1. Alkanes

    Science.gov (United States)

    Clark, R.N.; Curchin, J.M.; Hoefen, T.M.; Swayze, G.A.

    2009-01-01

    Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the. universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even ' when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.

  19. Regional calibration models for predicting loblolly pine tracheid properties using near-infrared spectroscopy

    Science.gov (United States)

    Mohamad Nabavi; Joseph Dahlen; Laurence Schimleck; Thomas L. Eberhardt; Cristian Montes

    2018-01-01

    This study developed regional calibration models for the prediction of loblolly pine (Pinus taeda) tracheid properties using near-infrared (NIR) spectroscopy. A total of 1842 pith-to-bark radial strips, aged 19–31 years, were acquired from 268 trees from 109 stands across the southeastern USA. Diffuse reflectance NIR spectra were collected at 10-mm...

  20. The use of near infrared spectroscopy (NIRS) to predict the chemical ...

    African Journals Online (AJOL)

    resias

    Keywords: NIRS, ostrich TMR, chemical composition, nutritive value ... For adequate feeding of livestock, farmers need information about the nutritive value of available .... presented a SD/SECV ratio value of less than three, which is regarded as fair, .... The current and future role of near infrared reflectance spectroscopy in.

  1. Structural characterization of ammonium uranate by infrared spectroscopy

    International Nuclear Information System (INIS)

    Rodriguez S, A.

    1994-01-01

    Infrared spectroscopy have been used to investigate the chemical composition of some ammonium uranates. In this study, I have attempted to establish the interrelationship between the structure of the products, the character of their infrared spectra and x-ray diffraction data capable of consistent interpretation in terms of defining the compounds. (Author)

  2. IR Cards: Inquiry-Based Introduction to Infrared Spectroscopy

    Science.gov (United States)

    Bennett, Jacqueline; Forster, Tabetha

    2010-01-01

    As infrared spectroscopy (IR) is frequently used in undergraduate organic chemistry courses, an inductive introduction to IR spectroscopy that uses index cards printed with spectra, structures, and chemical names is described. Groups of students are given an alphabetized deck of these "IR cards" to sort into functional groups. The students then…

  3. Near-infrared spectroscopy during peripheral vascular surgery

    DEFF Research Database (Denmark)

    Eiberg, J P; Schroeder, T V; Vogt, K C

    1997-01-01

    Near-infrared spectroscopy was performed perioperatively on the dorsum of the foot in 14 patients who underwent infrainguinal bypass surgery using a prosthesis or the greater saphenous vein. Dual-wavelength continuous light spectroscopy was used to assess changes in tissue saturation before, duri...

  4. Near infrared spectroscopy for qualitative comparison of pharmaceutical batches.

    Science.gov (United States)

    Roggo, Y; Roeseler, C; Ulmschneider, M

    2004-11-19

    Pharmaceuticals are produced according to current pharmacopoeias, which require quality parameters. Tablets of identical formulation, produced by different factories should have the same properties before and after storage. In this article, we analyzed samples having two different origins before and after storage (30 degrees C, 75% relative moisture). The aim of the study is to propose two approaches to understand the differences between origins and the storage effect by near infrared spectroscopy. In the first part, the main wavelengths are identified in transmittance and reflectance near infrared spectra in order to identify the major differences between the samples. In this paper, this approach is called fingerprinting. In the second part, principal component analysis (PCA) is computed to confirm the fingerprinting interpretation. The two interpretations show the differences between batches: physical aspect and moisture content. The manufacturing process is responsible for the physical differences between batches. During the storage, changes are due to the increase of moisture content and the decrease of the active content.

  5. Infrared characterization of environmental samples by pulsed photothermal spectroscopy

    International Nuclear Information System (INIS)

    Seidel, W.; Foerstendorf, H.; Heise, K.H.; Nicolai, R.; Schamlott, A.; Ortega, J.M.; Glotin, F.; Prazeres, R.

    2004-01-01

    Low concentration of toxic radioactive metals in environmental samples often limits the interpretation of results of infrared studies investigating the interaction processes between the metal ions and environmental compartments. For the first time, we could show that photothermal infrared spectroscopy performed with a pulsed free electron laser can provide reliable infrared spectra throughout a distinct spectral range of interest. In this model investigation, we provide vibrational absorption spectra of a rare earth metal salt dissolved in a KBr matrix and a natural calcite sample obtained by photothermal beam deflection (PTBD) technique and FT-IR (Fourier-transform infrared) spectroscopy, respectively. General agreement was found between all spectra of the different recording techniques. Spectral deviations were observed with samples containing low concentration of the rare earth metal salt indicating a lower detection limit of the photothermal method as compared to conventional FT-IR spectroscopy. (authors)

  6. Development of paints with infrared radiation reflective properties

    Directory of Open Access Journals (Sweden)

    Eliane Coser

    2015-06-01

    Full Text Available AbstractLarge buildings situated in hot regions of the Globe need to be agreeable to their residents. Air conditioning is extensively used to make these buildings comfortable, with consequent energy consumption. Absorption of solar visible and infrared radiations are responsible for heating objects on the surface of the Earth, including houses and buildings. To avoid excessive energy consumption, it is possible to use coatings formulated with special pigments that are able to reflect the radiation in the near- infrared, NIR, spectrum. To evaluate this phenomenon an experimental study about the reflectivity of paints containing infrared-reflective pigments has been made. By irradiating with an IR source and by measuring the surface temperatures of the samples we evaluated: color according to ASTM D 2244-14, UV/VIS/NIR reflectance according to ASTM E 903-12 and thermal performance. Additionally, the spectral reflectance and the IR emittance were measured and the solar reflectance of the samples were calculated. The results showed that plates coated with paints containing IR-reflecting pigments displayed lower air temperature on the opposite side as compared to conventional coatings, indicating that they can be effective to reflect NIR and decrease the temperature of buildings when used in roofs and walls.

  7. Infrared Spectroscopy of HNO and Noh Suspended in Solid Parahydrogen

    Science.gov (United States)

    Anderson, David T.; Ruzi, Mahmut

    2013-06-01

    The only report in the literature on the infrared spectroscopy of the parent oxynitrene NOH was performed using Ar matrix isolation spectroscopy at 10 K. In this previous study, the NOH is synthesized by co-deposition of NO/Ar and a H_2/Ar mixture that is passed through a microwave discharge to create H-atoms. The H-atoms recombine with NO in the Ar matrix to produce mostly HNO, but some NOH is produced as well. In this work we irradiate NO doped parahydrogen solids at 2 K using 193 nm radiation which is known to generate H-atoms as by-products. After the photolysis laser is stopped, we detect growth of HNO and NOH presumably due to reactions of H-atoms with NO analogous to the previous Ar matrix study. The higher energy NOH isomer is predicted by high-level calculations to be in a triplet ground electronic state. Interestingly, the infrared absorptions of NOH for the two observed vibrational modes (bend and OH stretch) display fine structure; an intense central peak with smaller peaks spaced symmetrically to both lower and higher wavenumbers. Further, the spacing between the peaks is the same for both vibrational modes. We believe this fine structure reflects the zero-field splitting of the triplet ground state of NOH (magnetic dipole-dipole interaction) and our most current results and analysis will be presented. G. Maier, H. P. Reisenauer, M. De Marco, Angew. Chem. Int. Ed. 38, 108-110 (1999). M. Fushitani and T. Momose, Low Temp. Phys. 29, 740-743 (2003). U. Bozkaya, J. M. Turney, Y. Yamaguchi, and H. F. Schaefer III, J. Chem. Phys. 136, 164303 (2012).

  8. Determination of quercetins in onion (Allium cepa) using infrared spectroscopy.

    Science.gov (United States)

    Lu, Xiaonan; Ross, Carolyn F; Powers, Joseph R; Rasco, Barbara A

    2011-06-22

    The rapid quantification of flavonoid compounds in onions by attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy combined with multivariate analysis was evaluated as a possible alternative to high-performance liquid chromatography (HPLC) analysis. Quercetin content in onion varieties (yellow, red, and sweet) was quantified using ATR FT-IR (4000 to 400 cm⁻¹) spectroscopy and HPLC methods. Quercetin-3,4'-O-diglucoside (3,4'-Qdg) and quercetin-4'-O-glucoside (4'-Qmg) comprised >80% of the total flavonol content detected in the studied varieties. The quercetin compounds (3,4'-Qdg and 4'-Qmg) and total flavonol conjugates were quantified by HPLC, and results correlated closely with ATR-IR values (R > 0.95). Cross-validated (leave-one-out) partial least-squares regression (PLSR) models successfully predicted concentrations of these quercetins. The standard errors of cross-validation (SECV) of 3,4'-Qdg and 4'-Qmg, total quercetin, and total flavonol contents of onions were 20.43, 21.18, and 21.02 mg/kg fresh weight, respectively. In addition, supervised and unsupervised segregation analyses (principal component analysis, discriminant function analysis, and soft independent modeling of class analogue) were performed to classify onion varieties on the basis of unique infrared spectral features. There was a high degree of segregation (interclass distances > 3.0) for the different types of onion. This study indicated that the IR technique could predict 3,4'-Qdg, 4'-Qmg, total quercetin, and total flavonol contents and has advantages over the traditional HPLC method in providing a valid, efficient, and cost-effective method requiring less sample preparation for the quantification of quercetins in onion.

  9. Infrared reflectance as a diagnostic adjunct for subclinical commotio retinae

    Directory of Open Access Journals (Sweden)

    Nicholas H Andrew

    2014-01-01

    Full Text Available Commotio retinae (CR is an outer retinal disorder following blunt trauma to the eye. Histologically it is characterized by disruption of the photoreceptor outer segments (OS, typically without injury to other retinal layers. Using spectral-domain optical coherence tomography (OCT the condition is visible as hyper-reflectivity of the OS. Most cases of CR are associated with transient grey-white discoloration of the retina and are easily diagnosed clinically, but there have been reports of OCT-confirmed CR without retinal discoloration. It is likely that this subclinical variant of CR is under-recognized as the OCT features of CR are subtle. Here, we report a case of OCT-confirmed subclinical CR that demonstrated prominent infrared hypo-reflectance, using the infrared protocol of the SPECTRALIS® OCT, Heidelberg Engineering. This case suggests that infrared reflectance may have a role in diagnosing cases of subclinical CR.

  10. Far-infrared spectroscopy of HII regions

    International Nuclear Information System (INIS)

    Emery, R.J.; Kessler, M.F.

    1984-01-01

    Interest has developed rapidly in the astrophysics associated with far-infrared line emission from ionised regions, following the development of spectroscopic instruments and observing facilities appropriate to those wavelengths. Far-infrared observations and their interpretation are now at the stage where the need for specific developments in theoretical and laboratory work have been identified. The need is also apparent for the development of models dealing with more realistic astrophysical situations. (Auth.)

  11. Infrared spectroscopy of Landau levels of graphene.

    Science.gov (United States)

    Jiang, Z; Henriksen, E A; Tung, L C; Wang, Y-J; Schwartz, M E; Han, M Y; Kim, P; Stormer, H L

    2007-05-11

    We report infrared studies of the Landau level (LL) transitions in single layer graphene. Our specimens are density tunable and show in situ half-integer quantum Hall plateaus. Infrared transmission is measured in magnetic fields up to B=18 T at selected LL fillings. Resonances between hole LLs and electron LLs, as well as resonances between hole and electron LLs, are resolved. Their transition energies are proportional to sqrt[B], and the deduced band velocity is (-)c approximately equal to 1.1 x 10(6) m/s. The lack of precise scaling between different LL transitions indicates considerable contributions of many-particle effects to the infrared transition energies.

  12. Cancer diagnosis by infrared spectroscopy: methodological aspects

    Science.gov (United States)

    Jackson, Michael; Kim, Keith; Tetteh, John; Mansfield, James R.; Dolenko, Brion; Somorjai, Raymond L.; Orr, F. W.; Watson, Peter H.; Mantsch, Henry H.

    1998-04-01

    IR spectroscopy is proving to be a powerful tool for the study and diagnosis of cancer. The application of IR spectroscopy to the analysis of cultured tumor cells and grading of breast cancer sections is outlined. Potential sources of error in spectral interpretation due to variations in sample histology and artifacts associated with sample storage and preparation are discussed. The application of statistical techniques to assess differences between spectra and to non-subjectively classify spectra is demonstrated.

  13. Production of high temperature superconductors and characteristics by infrared and Raman spectroscopy

    International Nuclear Information System (INIS)

    Thomsen, C.

    1991-01-01

    This final report, which is partly kept short, is concerned with electron/phonon interaction and the determination of the band gap in high temperature superconductors (YBa 2 Cu 3 O 7 ). The final report is divided into four parts, which reflect the individual working groups: 1. Raman spectroscopy, 2. IR spectroscopy (reflection measurements, isotope effect, superconducting energy gap, behaviour of infrared active phonons), 3. Magnetic field measurements, and 4. Theory (initial calculation of the metal/isolator transfer in BaBiO 3 ). (MM) [de

  14. WW Domain Folding Complexity Revealed by Infrared Spectroscopy

    OpenAIRE

    Davis, Caitlin M.; Dyer, R. Brian

    2014-01-01

    Although the intrinsic tryptophan fluorescence of proteins offers a convenient probe of protein folding, interpretation of the fluorescence spectrum is often difficult because it is sensitive to both global and local changes. Infrared (IR) spectroscopy offers a complementary measure of structural changes involved in protein folding, because it probes changes in the secondary structure of the protein backbone. Here we demonstrate the advantages of using multiple probes, infrared and fluorescen...

  15. Infrared and Raman Spectroscopy Principles and Spectral Interpretation

    CERN Document Server

    Larkin, Peter

    2011-01-01

    Infrared and Raman Spectroscopy: Principles and Spectral Interpretation explains the background, core principles and tests the readers understanding of the important techniques of Infrared and Raman Spectroscopy. These techniques are used by chemists, environmental scientists, forensic scientists etc to identify unknown chemicals. In the case of an organic chemist these tools are part of an armory of techniques that enable them to conclusively prove what compound they have made, which is essential for those being used in medical applications. The book reviews basic principles, instrumentation

  16. Infrared absorption spectroscopy and chemical kinetics of free radicals

    Energy Technology Data Exchange (ETDEWEB)

    Curl, R.F.; Glass, G.P. [Rice Univ., Houston, TX (United States)

    1993-12-01

    This research is directed at the detection, monitoring, and study of chemical kinetic behavior by infrared absorption spectroscopy of small free radical species thought to be important intermediates in combustion. During the last year, infrared kinetic spectroscopy using excimer laser flash photolysis and color-center laser probing has been employed to study the high resolution spectrum of HCCN, the rate constant of the reaction between ethynyl (C{sub 2}H) radical and H{sub 2} in the temperature region between 295 and 875 K, and the recombination rate of propargyl (CH{sub 2}CCH) at room temperature.

  17. Far infrared spectroscopy of H II regions

    International Nuclear Information System (INIS)

    Ward, D.B.

    1976-01-01

    A fully liquid helium cooled grating spectrometer has been developed for far infrared observations from the NASA Lear Jet. This instrument has been used in observations of the galactic HII regions M42 and M17. The instrument is described, and the results of various performance tests and calibrations are presented. The methods employed in observations from the Lear Jet are described, and the data analysis procedures are discussed. The results of a search for the (O III) 88.16 micron fine structure line are presented. The intensity of the line in M17 is reported, and an upper limit given for the intensity in M42. These results are compared with theoretical predictions, and future applications of infrared line observations are discussed. Coarse resolution spectra of M42 and M17 from 45 to 115 microns are also presented. The emission from M42 is shown to be a very smooth function of wavelength, closely fitting the wavelength dependence of a 105 0 K graybody. The spectrum of M17 is very different, having a bump at approximately 75 microns and a general far infrared excess. The observed spectrum is compared to the predictions of models for M17

  18. Studies of dust grain properties in infrared reflection nebulae.

    Science.gov (United States)

    Pendleton, Y J; Tielens, A G; Werner, M W

    1990-01-20

    We have developed a model for reflection nebulae around luminous infrared sources embedded in dense dust clouds. The aim of this study is to determine the sizes of the scattering grains. In our analysis, we have adopted an MRN-like power-law size distribution (Mathis, Rumpl, and Nordsieck) of graphite and silicate grains, but other current dust models would give results which were substantially the same. In the optically thin limit, the intensity of the scattered light is proportional to the dust column density, while in the optically thick limit, it reflects the grain albedo. The results show that the shape of the infrared spectrum is the result of a combination of the scattering properties of the dust, the spectrum of the illuminating source, and foreground extinction, while geometry plays a minor role. Comparison of our model results with infrared observations of the reflection nebula surrounding OMC-2/IRS 1 shows that either a grain size distribution like that found in the diffuse interstellar medium, or one consisting of larger grains, can explain the observed shape of the spectrum. However, the absolute intensity level of the scattered light, as well as the observed polarization, requires large grains (approximately 5000 angstroms). By adding water ice mantles to the silicate and graphite cores, we have modeled the 3.08 micrometers ice band feature, which has been observed in the spectra of several infrared reflection nebulae. We show that this ice band arises naturally in optically thick reflection nebulae containing ice-coated grains. We show that the shape of the ice band is diagnostic of the presence of large grains, as previously suggested by Knacke and McCorkle. Comparison with observations of the BN/KL reflection nebula in the OMC-1 cloud shows that large ice grains (approximately 5000 angstroms) contribute substantially to the scattered light.

  19. Fourier transform infrared spectroscopy for sepia melanin

    CSIR Research Space (South Africa)

    Mbonyiryivuze, A

    2015-08-01

    Full Text Available Spectroscopy (FTIR) for assessing biogenic silica sample purity in geochemical analyses and palaeoenvironmental research,” Climate of the Past, vol. 7, p. 65- 74, 2011. [12] P. N. R. Sundar, Films minces à base de Si nanostructuré pour des cellules...

  20. Two-dimensional spectroscopy at infrared and optical frequencies

    OpenAIRE

    Hochstrasser, Robin M.

    2007-01-01

    This Perspective on multidimensional spectroscopy in the optical and infrared spectral regions focuses on the principles and the scientific and technical challenges facing these new fields. The methods hold great promise for advances in the visualization of time-dependent structural changes in complex systems ranging from liquids to biological assemblies, new materials, and fundamental physical processes. The papers in this special feature on multidimensional spectroscopy in chemistry, physic...

  1. Near-infrared imaging spectroscopy for counterfeit drug detection

    Science.gov (United States)

    Arnold, Thomas; De Biasio, Martin; Leitner, Raimund

    2011-06-01

    Pharmaceutical counterfeiting is a significant issue in the healthcare community as well as for the pharmaceutical industry worldwide. The use of counterfeit medicines can result in treatment failure or even death. A rapid screening technique such as near infrared (NIR) spectroscopy could aid in the search for and identification of counterfeit drugs. This work presents a comparison of two laboratory NIR imaging systems and the chemometric analysis of the acquired spectroscopic image data. The first imaging system utilizes a NIR liquid crystal tuneable filter and is designed for the investigation of stationary objects. The second imaging system utilizes a NIR imaging spectrograph and is designed for the fast analysis of moving objects on a conveyor belt. Several drugs in form of tablets and capsules were analyzed. Spectral unmixing techniques were applied to the mixed reflectance spectra to identify constituent parts of the investigated drugs. The results show that NIR spectroscopic imaging can be used for contact-less detection and identification of a variety of counterfeit drugs.

  2. Screening experiments of ecstasy street samples using near infrared spectroscopy.

    Science.gov (United States)

    Sondermann, N; Kovar, K A

    1999-12-20

    Twelve different sets of confiscated ecstasy samples were analysed applying both near infrared spectroscopy in reflectance mode (1100-2500 nm) and high-performance liquid chromatography (HPLC). The sets showed a large variance in composition. A calibration data set was generated based on the theory of factorial designs. It contained 221 N-methyl-3,4-methylenedioxyamphetamine (MDMA) samples, 167 N-ethyl-3,4-methylenedioxyamphetamine (MDE), 111 amphetamine and 106 samples without a controlled substance, which will be called placebo samples thereafter. From this data set, PLS-1 models were calculated and were successfully applied for validation of various external laboratory test sets. The transferability of these results to confiscated tablets is demonstrated here. It is shown that differentiation into placebo, amphetamine and ecstasy samples is possible. Analysis of intact tablets is practicable. However, more reliable results are obtained from pulverised samples. This is due to ill-defined production procedures. The use of mathematically pretreated spectra improves the prediction quality of all the PLS-1 models studied. It is possible to improve discrimination between MDE and MDMA with the help of a second model based on raw spectra. Alternative strategies are briefly discussed.

  3. Galileo infrared imaging spectroscopy measurements at venus

    Science.gov (United States)

    Carlson, R.W.; Baines, K.H.; Encrenaz, Th.; Taylor, F.W.; Drossart, P.; Kamp, L.W.; Pollack, James B.; Lellouch, E.; Collard, A.D.; Calcutt, S.B.; Grinspoon, D.; Weissman, P.R.; Smythe, W.D.; Ocampo, A.C.; Danielson, G.E.; Fanale, F.P.; Johnson, T.V.; Kieffer, H.H.; Matson, D.L.; McCord, T.B.; Soderblom, L.A.

    1991-01-01

    During the 1990 Galileo Venus flyby, the Near Infrared Mapping Spectrometer investigated the night-side atmosphere of Venus in the spectral range 0.7 to 5.2 micrometers. Multispectral images at high spatial resolution indicate substantial cloud opacity variations in the lower cloud levels, centered at 50 kilometers altitude. Zonal and meridional winds were derived for this level and are consistent with motion of the upper branch of a Hadley cell. Northern and southern hemisphere clouds appear to be markedly different. Spectral profiles were used to derive lower atmosphere abundances of water vapor and other species.

  4. Extreme Ultraviolet Bragg mirrors with suppressed infrared reflectivity properties

    NARCIS (Netherlands)

    Medvedev, Viacheslav; Yakshin, Andrey; Louis, Eric; van de Kruijs, Robbert Wilhelmus Elisabeth; van den Boogaard, Toine; Krivtsun, V.M.; Yakinun, A.M.; Bijkerk, Frederik

    2013-01-01

    Many optical applications demand high reflectivity in a particular wavelength range while simultaneously requiring suppression of radiation outside this range. Such parasitic radiation can for instance lead to image distortions in imaging applications or poor signal-noise ratios in spectroscopy. The

  5. Extreme Ultraviolet Bragg mirrors with suppressed infrared reflectivity properties

    NARCIS (Netherlands)

    Medvedev, Viacheslav; Yakshin, Andrey; Louis, Eric; van de Kruijs, Robbert Wilhelmus Elisabeth; van den Boogaard, Toine; Krivtsun, V.M.; Yakunin, A.M.; Bijkerk, Frederik

    2012-01-01

    Many optical applications demand high reflectivity in a particular wavelength range while simultaneously requiring suppression of radiation outside this range. Such parasitic radiation can for instance lead to image distortions in imaging applications or poor signal-noise ratios in spectroscopy. The

  6. Predição da composição química de bermudas (Cynodon spp. pela espectroscopia de reflectância no infravermelho proximal Prediction of chemical composition of Cynodon spp. by near infrared reflectance spectroscopy

    Directory of Open Access Journals (Sweden)

    Roberto Serena Fontaneli

    2004-08-01

    Full Text Available Diversos cultivares de Cynodon dactylon têm sido cultivados no Rio Grande do Sul para alimentação do rebanho leiteiro, na forma de pastejo ou feno. A rápida determinação do valor nutritivo dessas forrageiras pode ser útil para seu manejo e para o planejamento da dieta dos animais. Este trabalho teve como objetivo desenvolver curvas de calibração para análise do valor nutritivo de quatro cultivares de Cynodon (Tifton 68, Tifton 85, Florakirk, Coastcross, utilizando o método de reflectância no infravermelho proximal (NIRS. Foram utilizadas 129 amostras de forragem verde, coletadas e analisadas entre 1998 e 2001. Os coeficientes de determinação para proteína bruta, fibra insolúvel em detergente neutro, fibra insolúvel em detergente ácido, matéria seca, cálcio, fósforo, potássio e magnésio foram, respectivamente: 0,98; 0,97; 0,99; 1; 0,92; 0,97; 0,99 e 0,72%. Os erros-padrão de calibração foram de 0,38; 0,60; 0,35; 0,14; 0,02; 0,01; 0,05 e 0,01%, respectivamente. As equações obtidas foram consideradas de excelente resolução para todos os parâmetros estimados, o que indica a acurácia do método para a espécie avaliada.Many Cynodon dactylon cultivars have been cultivated in Rio Grande do Sul state to be used as pasture or hay to feed dairy cattle. Quick determination of the nutritional value of these forages would be valuable for management and diet planning. This work had the objective to develop calibration curves for analysis of the nutritional value of four Cynodon cultivars (Tifton 68, Tifton 85, Florakirk, Coastcross, using near infrared reflectance spectroscopy (NIRS. A total of 129 fresh samples of green pasture were collected and analyzed from 1998 to 2001. The determination coefficients for crude protein, neutral detergent fiber, acid detergent fiber, dry matter, calcium, phosphorus, potash and magnesium were, respectively, .98, .97, .99, 1, .92, .97, .99 and .72%. The calibration standard error for the same

  7. Quantifying cerebral hypoxia by near-infrared spectroscopy tissue oximetry

    DEFF Research Database (Denmark)

    Rasmussen, Martin B.; Eriksen, Vibeke R.; Andresen, Bjørn

    2017-01-01

    Tissue oxygenation estimated by near-infrared spectroscopy (NIRS) is a volume-weighted mean of the arterial and venous hemoglobin oxygenation. In vivo validation assumes a fixed arterial-to-venous volume-ratio (AV-ratio). Regulatory cerebro-vascular mechanisms may change the AV-ratio. We used...

  8. Progress in far-infrared spectroscopy: Approximately 1890 to 1970

    Science.gov (United States)

    Mitsuishi, Akiyoshi

    2014-03-01

    The history of far-infrared spectroscopy from its beginning to around 1970 is reviewed. Before World War II, the size of the community investigating this topic was limited. During this period, in particular before 1925, about 90% of the papers were published by H. Rubens and his co-workers in Germany. One or two researchers from the US joined the Rubens group per year from 1890 to the beginning of 1910. During the next year or two, some researchers joined M. Czerny, who is seen as the successor of Rubens. After World War II, far-infrared techniques progressed further in the US, which did not suffer damage during the war. The advanced techniques of far-infrared grating spectroscopy were transferred from the US (R. A. Oetjen) to Japan (H. Yoshinaga). Yoshinaga and his co-workers expanded the techniques by themselves. This paper describes the historical development of far-infrared spectroscopy before Fourier transform spectroscopy became popular around 1970.

  9. WW domain folding complexity revealed by infrared spectroscopy.

    Science.gov (United States)

    Davis, Caitlin M; Dyer, R Brian

    2014-09-02

    Although the intrinsic tryptophan fluorescence of proteins offers a convenient probe of protein folding, interpretation of the fluorescence spectrum is often difficult because it is sensitive to both global and local changes. Infrared (IR) spectroscopy offers a complementary measure of structural changes involved in protein folding, because it probes changes in the secondary structure of the protein backbone. Here we demonstrate the advantages of using multiple probes, infrared and fluorescence spectroscopy, to study the folding of the FBP28 WW domain. Laser-induced temperature jumps coupled with fluorescence or infrared spectroscopy have been used to probe changes in the peptide backbone on the submillisecond time scale. The relaxation dynamics of the β-sheets and β-turn were measured independently by probing the corresponding IR bands assigned in the amide I region. Using these wavelength-dependent measurements, we observe three kinetics phases, with the fastest process corresponding to the relaxation kinetics of the turns. In contrast, fluorescence measurements of the wild-type WW domain and tryptophan mutants exhibit single-exponential kinetics with a lifetime that corresponds to the slowest phase observed by infrared spectroscopy. Mutant sequences provide evidence of an intermediate dry molten globule state. The slowest step in the folding of this WW domain is the tight packing of the side chains in the transition from the dry molten globule intermediate to the native structure. This study demonstrates that using multiple complementary probes enhances the interpretation of protein folding dynamics.

  10. Waiting Time Dynamics in Two-Dimensional Infrared Spectroscopy

    NARCIS (Netherlands)

    Jansen, Thomas L. C.; Knoester, Jasper

    We review recent work on the waiting time dynamics of coherent two-dimensional infrared (2DIR) spectroscopy. This dynamics can reveal chemical and physical processes that take place on the femto- and picosecond time scale, which is faster than the time scale that may be probed by, for example,

  11. Mid-infrared quantum cascade laser spectroscopy probing of the ...

    Indian Academy of Sciences (India)

    Aparajeo Chattopadhyay

    2018-05-07

    May 7, 2018 ... cm3 molecule. −1 s. −1 ... Quantum cascade laser; time-resolved mid-infrared spectroscopy; transient absorption; peroxy radicals .... peak of the laser emission profile. .... cal with O2 is a termolecular reaction (Eq. 3) and the.

  12. Fourier transform infrared (FTIR) spectroscopy for identification of ...

    African Journals Online (AJOL)

    Fourier transform infrared (FTIR) spectroscopy was used in this study to identify and determine spectral features of Chlorella vulgaris Beijerinck 1890 and Scenedesmus obliquus (Turpin) Kützing 1833. Two cultures were grown in a chemically-defined media under photoautotrophic culture conditions isolated from eutrophic ...

  13. Broadband integrated mid infrared light sources as enabling technology for point of care mid-infrared spectroscopy

    Science.gov (United States)

    2017-08-20

    AFRL-AFOSR-JP-TR-2017-0061 Broadband integrated mid-infrared light sources as enabling technology for point-of-care mid- infrared spectroscopy Alex...mid-infrared light sources as enabling technology for point-of-care mid-infrared spectroscopy 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA2386-16-1-4037...Broadband integrated mid-infrared light sources as enabling technology for point-of-care mid- infrared spectroscopy ” Date: 16th August 2017 Name

  14. High resolution spectroscopy in the microwave and far infrared

    Science.gov (United States)

    Pickett, Herbert M.

    1990-01-01

    High resolution rotational spectroscopy has long been central to remote sensing techniques in atmospheric sciences and astronomy. As such, laboratory measurements must supply the required data to make direct interpretation of data for instruments which sense atmospheres using rotational spectra. Spectral measurements in the microwave and far infrared regions are also very powerful tools when combined with infrared measurements for characterizing the rotational structure of vibrational spectra. In the past decade new techniques were developed which have pushed high resolution spectroscopy into the wavelength region between 25 micrometers and 2 mm. Techniques to be described include: (1) harmonic generation of microwave sources, (2) infrared laser difference frequency generation, (3) laser sideband generation, and (4) ultrahigh resolution interferometers.

  15. Computing protein infrared spectroscopy with quantum chemistry.

    Science.gov (United States)

    Besley, Nicholas A

    2007-12-15

    Quantum chemistry is a field of science that has undergone unprecedented advances in the last 50 years. From the pioneering work of Boys in the 1950s, quantum chemistry has evolved from being regarded as a specialized and esoteric discipline to a widely used tool that underpins much of the current research in chemistry today. This achievement was recognized with the award of the 1998 Nobel Prize in Chemistry to John Pople and Walter Kohn. As the new millennium unfolds, quantum chemistry stands at the forefront of an exciting new era. Quantitative calculations on systems of the magnitude of proteins are becoming a realistic possibility, an achievement that would have been unimaginable to the early pioneers of quantum chemistry. In this article we will describe ongoing work towards this goal, focusing on the calculation of protein infrared amide bands directly with quantum chemical methods.

  16. Infrared quantitative spectroscopy and planetary atmospheres

    Science.gov (United States)

    Flaud, J.-M.

    2009-04-01

    Optical measurements of atmospheric minor constituents are carried out using spectrometers working in the UV-visible, infrared and microwave spectral ranges. In all cases the quality of the analysis and of the interpretation of the atmospheric spectra requires the best possible knowledge of the molecular parameters of the species of interest. To illustrate this point we will concentrate on recent laboratory studies of nitric acid, chlorine nitrate and formaldehyde. Nitric acid is one of the important minor constituent of the terrestrial atmosphere. Using new and accurate experimental results concerning the spectroscopic properties of the H14NO3 and H15NO3 molecules, as well as improved theoretical methods (Perrin et al., 2004), it has been possible to generate an improved set of line parameters for these molecules in the 11.2 μm spectral region. These line parameters were used to detect for the first time the H15NO3 molecule in the atmosphere analyzing atmospheric spectra recorded by the MIPAS experiment. The retrievals of chlorine nitrate profiles are usually performed using absorption cross sections (Birk and Wagner, 2003). Following a high resolution analysis of the ν3 and ν4bands of this species in the 12.8 μm region wepropose, as a possibility, to use line by line calculation simulating its ν4Q-branch for the atmospheric temperature and pressure ranges. For the measurement of atmospheric formaldehyde concentrations, mid-infrared and ultraviolet absorptions are both used by ground, air or satellite instruments. It is then of the utmost importance to have consistent spectral parameters in these various spectral domains. Consequently the aim of the study performed at LISA (Gratien et al., 2007) was to intercalibrate formaldehyde spectra in the infrared and ultraviolet regions acquiring simultaneously UV and IR spectra using a common optical cell. The results of the work will be presented. Also high resolution infrared data derived from Perrin et al., 2003

  17. Bird sexing by Fourier transform infrared spectroscopy

    Science.gov (United States)

    Steiner, Gerald; Bartels, Thomas; Krautwald-Junghanns, Maria-Elisabeth; Koch, Edmund

    2010-02-01

    Birds are traditionally classified as male or female based on their anatomy and plumage color as judged by the human eye. Knowledge of a bird's gender is important for the veterinary practitioner, the owner and the breeder. The accurate gender determination is essential for proper pairing of birds, and knowing the gender of a bird will allow the veterinarian to rule in or out gender-specific diseases. Several biochemical methods of gender determination have been developed for avian species where otherwise the gender of the birds cannot be determined by their physical appearances or characteristics. In this contribution, we demonstrate that FT-IR spectroscopy is a suitable tool for a quick and objective determination of the bird's gender. The method is based on differences in chromosome size. Male birds have two Z chromosomes and female birds have a W-chromosome and a Z-chromosome. Each Z-chromosome has approx. 75.000.000 bps whereas the W-chromosome has approx. 260.00 bps. This difference can be detected by FT-IR spectroscopy. Spectra were recorded from germ cells obtained from the feather pulp of chicks as well as from the germinal disk of fertilized but non-bred eggs. Significant changes between cells of male and female birds occur in the region of phosphate vibrations around 1080 and 1120 cm-1.

  18. Efective infrared reflectivity and dielectric function of polycrystalline alumina ceramics

    Czech Academy of Sciences Publication Activity Database

    Nuzhnyy, Dmitry; Petzelt, Jan; Borodavka, Fedir; Vaněk, Přemysl; Šimek, Daniel; Trunec, D.; Maca, K.

    2017-01-01

    Roč. 254, č. 5 (2017), s. 1-8, č. článku 1600607. ISSN 0370-1972 R&D Projects: GA ČR GA15-08389S Institutional support: RVO:68378271 Keywords : alumina * ceramics * effective dielectric function * effective medium approximation * geometrical resonances * infrared reflectivity Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.674, year: 2016

  19. Infrared spectroscopy for studying structure and aging effects in rhamnolipid biosurfactants

    OpenAIRE

    Kiefer, Johannes; Radzuan, Mohd Nazren; Winterburn, James

    2017-01-01

    Biosurfactants are produced by microorganisms and represent amphiphilic compounds with polar and non-polar moieties; hence they can be used to stabilize emulsions, e.g. in the cosmetic and food sectors. Their structure and its changes when exposed to light and elevated temperature are yet to be fully understood. In this study, we demonstrate that attenuated total reflection infrared (ATR-IR) spectroscopy is a useful tool for the analysis of biosurfactants, using rhamnolipids produced by ferme...

  20. Thermal consequences of colour and near-infrared reflectance.

    Science.gov (United States)

    Stuart-Fox, Devi; Newton, Elizabeth; Clusella-Trullas, Susana

    2017-07-05

    The importance of colour for temperature regulation in animals remains controversial. Colour can affect an animal's temperature because all else being equal, dark surfaces absorb more solar energy than do light surfaces, and that energy is converted into heat. However, in reality, the relationship between colour and thermoregulation is complex and varied because it depends on environmental conditions and the physical properties, behaviour and physiology of the animal. Furthermore, the thermal effects of colour depend as much on absorptance of near-infrared ((NIR), 700-2500 nm) as visible (300-700 nm) wavelengths of direct sunlight; yet the NIR is very rarely considered or measured. The few available data on NIR reflectance in animals indicate that the visible reflectance is often a poor predictor of NIR reflectance. Adaptive variation in animal coloration (visible reflectance) reflects a compromise between multiple competing functions such as camouflage, signalling and thermoregulation. By contrast, adaptive variation in NIR reflectance should primarily reflect thermoregulatory requirements because animal visual systems are generally insensitive to NIR wavelengths. Here, we assess evidence and identify key research questions regarding the thermoregulatory function of animal coloration, and specifically consider evidence for adaptive variation in NIR reflectance.This article is part of the themed issue 'Animal coloration: production, perception, function and application'. © 2017 The Author(s).

  1. Direct determination of sorbitol and sodium glutamate by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) in the thermostabilizer employed in the production of yellow-fever vaccine.

    Science.gov (United States)

    de Castro, Eduardo da S G; Cassella, Ricardo J

    2016-05-15

    Reference methods for quality control of vaccines usually require treatment of the samples before analysis. These procedures are expensive, time-consuming, unhealthy and require careful manipulation of the sample, making them a potential source of analytical errors. This work proposes a novel method for the quality control of thermostabilizer samples of the yellow fever vaccine employing attenuated total reflectance Fourier transform infrared spectrometry (ATR-FTIR). The main advantage of the proposed method is the possibility of direct determination of the analytes (sodium glutamate and sorbitol) without any pretreatment of the samples. Operational parameters of the FTIR technique, such as the number of accumulated scans and nominal resolution, were evaluated. The best conditions for sodium glutamate were achieved when 64 scans were accumulated using a nominal resolution of 4 cm(-1). The measurements for sodium glutamate were performed at 1347 cm(-1) (baseline correction between 1322 and 1369 cm(-1)). In the case of sorbitol, the measurements were done at 890cm(-1) (baseline correction between 825 and 910 cm(-1)) using a nominal resolution of 2 cm(-1) with 32 accumulated scans. In both cases, the quantitative variable was the band height. Recovery tests were performed in order to evaluate the accuracy of the method and recovery percentages in the range 93-106% were obtained. Also, the methods were compared with reference methods and no statistical differences were observed. The limits of detection and quantification for sodium glutamate were 0.20 and 0.62% (m/v), respectively, whereas for sorbitol they were 1 and 3.3% (m/v), respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Microscale Solubility Measurements of Matrix-Assisted Laser Desorption-Ionization (MALDI) Matrices Using Attenuated Total Reflection (ATR) Fourier Transform Infrared Spectroscopy (FT-IR) Coupled with Partial Least Squares (PLS) Analysis.

    Science.gov (United States)

    Gorre, Elsa; Owens, Kevin G

    2016-11-01

    In this work an attenuated total reflection Fourier transform infrared (FT-IR) absorption based method is used to measure the solubility of two matrix-assisted laser desorption-ionization (MALDI) matrices in a few pure solvents and mixtures of acetonitrile and water using low microliter amounts of solution. Results from a method that averages the values obtained from multiple calibration curves created by manual peak picking are compared to those predicted using a partial least squares (PLS) chemometrics approach. The PLS method provided solubility values that were in good agreement with the manual method with significantly greater ease of analysis. As a test, the solubility of adipic acid in acetone was measured using the two methods of analysis, and the values are in good agreement with solubility values reported in literature. The solubilities of the MALDI matrices α-cyano-4-hydroxy cinnamic acid (CHCA) and sinapinic acid (SA) were measured in a series of mixtures made from acetonitrile (ACN) and water; surprisingly, the results show a highly nonlinear trend. While both CHCA and SA show solubility values of less than 10 mg/mL in the pure solvents, the solubility value for SA increases to 56.3 mg/mL in a 75:25 v/v ACN:water mixture. This can have a significant effect on the matrix-to-analyte ratios in the MALDI experiment when sample protocols call for preparation of a saturated solution of the matrix in the chosen solvent system. © The Author(s) 2016.

  3. Characterization of InSb layers on GaAs substrates using infrared reflectance and a modified oscillator formula

    Energy Technology Data Exchange (ETDEWEB)

    Engelbrecht, J.A.A., E-mail: Japie.Engelbrecht@nmmu.ac.z [Physics Department, Nelson Mandela Metropolitan University, Box 77000, Port Elizabeth 6031 (South Africa); Wagener, M.C. [Physics Department, Nelson Mandela Metropolitan University, Box 77000, Port Elizabeth 6031 (South Africa)

    2009-12-01

    InSb epilayers on GaAs substrates are analyzed using infrared reflectance spectroscopy, but employing a modified Drude oscillator formula. The modified formula enables the determination of 13 parameters: six dielectric parameters for both layer and substrate separately, as well as the thickness of the layer. The formula is tested against previously published data, and to characterize layers grown in this laboratory.

  4. Characterization of InSb layers on GaAs substrates using infrared reflectance and a modified oscillator formula

    International Nuclear Information System (INIS)

    Engelbrecht, J.A.A.; Wagener, M.C.

    2009-01-01

    InSb epilayers on GaAs substrates are analyzed using infrared reflectance spectroscopy, but employing a modified Drude oscillator formula. The modified formula enables the determination of 13 parameters: six dielectric parameters for both layer and substrate separately, as well as the thickness of the layer. The formula is tested against previously published data, and to characterize layers grown in this laboratory.

  5. Infrared Spectroscopy of Discrete Uranyl Anion Complexes

    International Nuclear Information System (INIS)

    Groenewold, G. S.; Gianotto, Anita K.; McIIwain, Michael E.; Van Stipdonk, Michael J.; Kullman, Michael; Moore, David T.; Polfer, Nick; Oomens, Jos; Infante, Ivan A.; Visscher, Lucas; Siboulet, Bertrand; De Jong, Wibe A.

    2008-01-01

    The Free-Electron Laser for Infrared Experiments (FELIX) w 1 as used to study the wavelength-resolved multiple photon photodissociation of discrete, gas phase uranyl (UO2 2 2+) complexes containing a single anionic ligand (A), with or without ligated solvent molecules (S). The uranyl antisymmetric and symmetric stretching frequencies were measured for complexes with general formula [UO2A(S)n]+, where A was either hydroxide, methoxide, or acetate; S was water, ammonia, acetone, or acetonitrile; and n = 0-3. The values for the antisymmetric stretching frequency for uranyl ligated with only an anion ([UO2A]+) were as low or lower than measurements for [UO2]2+ ligated with as many as five strong neutral donor ligands, and are comparable to solution phase values. This result was surprising because initial DFT calculations predicted values that were 30-40 cm-1 higher, consistent with intuition but not with the data. Modification of the basis sets and use of alternative functionals improved computational accuracy for the methoxide and acetate complexes, but calculated values for the hydroxide were greater than the measurement regardless of the computational method used. Attachment of a neutral donor ligand S to [UO2A]+ produced [UO2AS]+, which produced only very modest changes to the uranyl antisymmetric stretch frequency, and did not universally shift the frequency to lower values. DFT calculations for [UO2AS]+ were in accord with trends in the data, and showed that attachment of the solvent was accommodated by weakening of the U-anion bond as well as the uranyl. When uranyl frequencies were compared for [UO2AS]+ species having different solvent neutrals, values decreased with increasing neutral nucleophilicity

  6. Synergy Effect of Combining Fluorescence and Mid Infrared Fiber Spectroscopy for Kidney Tumor Diagnostics

    Directory of Open Access Journals (Sweden)

    Andrey Bogomolov

    2017-11-01

    Full Text Available Matching pairs of tumor and non-tumor kidney tissue samples of four patients were investigated ex vivo using a combination of two methods, attenuated total reflection mid infrared spectroscopy and fluorescence spectroscopy, through respectively prepared and adjusted fiber probes. In order to increase the data information content, the measurements on tissue samples in both methods were performed in the same 31 preselected positions. Multivariate data analysis revealed a synergic effect of combining the two methods for the diagnostics of kidney tumor compared to individual techniques.

  7. Infrared Spectroscopy Beamline Based on a Tabletop Storage Ring

    OpenAIRE

    Haque, Md. Monirul; Moon, Ahsa; Yamada, Hironari

    2012-01-01

    An optical beamline dedicated to the infrared (IR) spectroscopy has been constructed at MIRRORCLE, a tabletop storage ring. The beamline has been designed for the use of infrared synchrotron radiation (IRSR) emitted from a bending magnet of 156 mm bending radius with the acceptance angle of 355(H) × 138(V) mrad to obtain high flux. The IR emission is forced by an exactly circular optics, named photon storage ring (PhSR), placed around the electron orbit and is collected by a “magic mirror” as...

  8. Synchrotron-based far-infrared spectroscopy of nickel tungstate

    International Nuclear Information System (INIS)

    Kalinko, A.; Kuzmin, A.; Roy, P.; Evarestov, R.A.

    2016-01-01

    Monoclinic antiferromagnetic NiWO 4 was studied by far-infrared (30-600 cm -1 ) absorption spectroscopy in the temperature range of 5-300 K using the synchrotron radiation from SOLEIL source. Two isomorphous CoWO 4 and ZnWO 4 tungstates were investigated for comparison. The phonon contributions in the far-infrared range of tungstates were interpreted using the first-principles spin-polarized linear combination of atomic orbital calculations. No contributions from magnetic excitations were found in NiWO 4 and CoWO 4 below their Neel temperatures down to 5 K.

  9. Exploring proton doping in poly-3-methylpyrrole by infrared spectroscopy

    International Nuclear Information System (INIS)

    Sanchez de la Blanca, E.; Carrillo, I.; Redondo, M.I.; Gonzalez-Tejera, M.J.; Garcia, M.V.

    2007-01-01

    Structural changes induced by electrochemical redox processes or by pH variations on conducting poly-3-methylpyrrole, electrochemically synthesized in NaClO 4 acetonitrile solution, have been studied by infrared spectroscopy. With this aim infrared spectra of perchlorate doped poly-3-methylpyrrole films at different oxidation states as well as after immersion in acid (pH = 1) and basic (pH = 12.6) aqueous solutions have been analysed. The existence of proton-doping mechanism in this polymer has been confirmed from the comparative study of spectra of oxidized/reduced and acid/basic treated polymer

  10. Infrared-emission spectroscopy of CO on Ni

    International Nuclear Information System (INIS)

    Chiang, S.; Tobin, R.G.; Richards, P.L.

    1982-09-01

    We report the first observation of thermally emitted infrared radiation from vibrational modes of molecules adsorbed on clean, single-crystal metal surfaces. The observation of emission from CO adsorbed on Ni demonstrates the surface sensitivity of a novel apparatus for infrared vibrational spectroscopy, with a resolution of 1 to 15 cm -1 over the frequency range from 330 to 3000 cm -1 . A liquid-helium-cooled grating spectrometer measures the thermal radiation from a room-temperature, single-crystal sample, which is mounted in an ultrahigh-vacuum system. Measurements of frequencies and linewidths of CO on a single-crystal Ni sample, as a function of coverage, are discussed

  11. Breast phantom for mammary tissue characterization by near infrared spectroscopy

    International Nuclear Information System (INIS)

    Miranda, D A; Cristiano, K L; Gutiérrez, J C

    2013-01-01

    Breast cancer is a disease associated to a high morbidity and mortality in the entire world. In the study of early detection of breast cancer the development of phantom is so important. In this research we fabricate a breast phantom using a ballistic gel with special modifications to simulate a normal and abnormal human breast. Optical properties of woman breast in the near infrared region were modelled with the phantom we developed. The developed phantom was evaluated with near infrared spectroscopy in order to study its relation with breast tissue. A good optical behaviour was achieved with the model fabricated

  12. Diffuse Reflectance Spectroscopy for Total Carbon Analysis of Hawaiian Soils

    Science.gov (United States)

    McDowell, M. L.; Bruland, G. L.; Deenik, J. L.; Grunwald, S.; Uchida, R.

    2010-12-01

    Accurate assessment of total carbon (Ct) content is important for fertility and nutrient management of soils, as well as for carbon sequestration studies. The non-destructive analysis of soils by diffuse reflectance spectroscopy (DRS) is a potential supplement or alternative to the traditional time-consuming and costly combustion method of Ct analysis, especially in spatial or temporal studies where sample numbers are large. We investigate the use of the visible to near-infrared (VNIR) and mid-infrared (MIR) spectra of soils coupled with chemometric analysis to determine their Ct content. Our specific focus is on Hawaiian soils of agricultural importance. Though this technique has been introduced to the soil community, it has yet to be fully tested and used in practical applications for all soil types, and this is especially true for Hawaii. In short, DRS characterizes and differentiates materials based on the variation of the light reflected by a material at certain wavelengths. This spectrum is dependent on the material’s composition, structure, and physical state. Multivariate chemometric analysis unravels the information in a set of spectra that can help predict a property such as Ct. This study benefits from the remarkably diverse soils of Hawaii. Our sample set includes 216 soil samples from 145 pedons from the main Hawaiian Islands archived at the National Soil Survey Center in Lincoln, NE, along with more than 50 newly-collected samples from Kauai, Oahu, Molokai, and Maui. In total, over 90 series from 10 of the 12 soil orders are represented. The Ct values of these samples range from < 1% - 55%. We anticipate that the diverse nature of our sample set will ensure a model with applicability to a wide variety of soils, both in Hawaii and globally. We have measured the VNIR and MIR spectra of these samples and obtained their Ct values by dry combustion. Our initial analyses are conducted using only samples obtained from the Lincoln archive. In this

  13. Immersion Gratings for Infrared High-resolution Spectroscopy

    Science.gov (United States)

    Sarugaku, Yuki; Ikeda, Yuji; Kobayashi, Naoto; Kaji, Sayumi; Sukegawa, Takashi; Sugiyama, Shigeru; Nakagawa, Takao; Arasaki, Takayuki; Kondo, Sohei; Nakanishi, Kenshi; Yasui, Chikako; Kawakita, Hideyo

    2016-10-01

    High-resolution spectroscopy in the infrared wavelength range is essential for observations of minor isotopologues, such as HDO for water, and prebiotic organic molecules like hydrocarbons/P-bearing molecules because numerous vibrational molecular bands (including non-polar molecules) are located in this wavelength range. High spectral resolution enables us to detect weak lines without spectral line confusion. This technique has been widely used in planetary sciences, e.g., cometary coma (H2O, CO, and organic molecules), the martian atmosphere (CH4, CO2, H2O and HDO), and the upper atmosphere of gas giants (H3+ and organic molecules such as C2H6). Spectrographs with higher resolution (and higher sensitivity) still have a potential to provide a plenty of findings. However, because the size of spectrographs scales with the spectral resolution, it is difficult to realize it.Immersion grating (IG), which is a diffraction grating wherein the diffraction surface is immersed in a material with a high refractive index (n > 2), provides n times higher spectral resolution compared to a reflective grating of the same size. Because IG reduces the size of spectrograph to 1/n compared to the spectrograph with the same spectral resolution using a conventional reflective grating, it is widely acknowledged as a key optical device to realize compact spectrographs with high spectral resolution.Recently, we succeeded in fabricating a CdZnTe immersion grating with the theoretically predicted diffraction efficiency by machining process using an ultrahigh-precision five-axis processing machine developed by Canon Inc. Using the same technique, we completed a practical germanium (Ge) immersion grating with both a reflection coating on the grating surface and the an AR coating on the entrance surface. It is noteworthy that the wide wavelength range from 2 to 20 um can be covered by the two immersion gratings.In this paper, we present the performances and the applications of the immersion

  14. Determinação de sibutramina em formas farmacêuticas através de espectroscopia no infravermelho com refletância difusa e métodos de calibração multivariada Determination of sibutramine in pharmaceutical formulations by diffuse reflectance infrared spectroscopy and multivariate calibration methods

    Directory of Open Access Journals (Sweden)

    Daniela Florencio Maluf

    2010-01-01

    Full Text Available The goal of this work is the development and validation of an analytical method for fast quantification of sibutramine in pharmaceutical formulations, using diffuse reflectance infrared spectroscopy and partial least square regression. The multivariate model was elaborated from 22 mixtures containing sibutramine and excipients (lactose, microcrystalline cellulose, colloidal silicon dioxide and magnesium stearate and using fragmented (750-1150/ 1350-1500/ 1850-1950/ 2600-2900 cm-1 and smoothing spectral data. Using 10 latent variables, excellent predictive capacity were observed in the calibration (n=20, RMSEC=0.004, R= 0.999 and external validation (n=5, RMSEC= 9.36, R=0.999 phases. In the analysis of synthetic mixtures the precision (SD=3,47% was compatible with the rules of the Agencia Nacional de Vigilância Sanitária (ANVISA-Brazil. In the analysis of commercial drugs good agreement was observed between spectroscopic and chromatographic methods.

  15. Fourier transform infrared spectroscopy for Kona coffee authentication.

    Science.gov (United States)

    Wang, Jun; Jun, Soojin; Bittenbender, H C; Gautz, Loren; Li, Qing X

    2009-06-01

    Kona coffee, the variety of "Kona typica" grown in the north and south districts of Kona-Island, carries a unique stamp of the region of Big Island of Hawaii, U.S.A. The excellent quality of Kona coffee makes it among the best coffee products in the world. Fourier transform infrared (FTIR) spectroscopy integrated with an attenuated total reflectance (ATR) accessory and multivariate analysis was used for qualitative and quantitative analysis of ground and brewed Kona coffee and blends made with Kona coffee. The calibration set of Kona coffee consisted of 10 different blends of Kona-grown original coffee mixture from 14 different farms in Hawaii and a non-Kona-grown original coffee mixture from 3 different sampling sites in Hawaii. Derivative transformations (1st and 2nd), mathematical enhancements such as mean centering and variance scaling, multivariate regressions by partial least square (PLS), and principal components regression (PCR) were implemented to develop and enhance the calibration model. The calibration model was successfully validated using 9 synthetic blend sets of 100% Kona coffee mixture and its adulterant, 100% non-Kona coffee mixture. There were distinct peak variations of ground and brewed coffee blends in the spectral "fingerprint" region between 800 and 1900 cm(-1). The PLS-2nd derivative calibration model based on brewed Kona coffee with mean centering data processing showed the highest degree of accuracy with the lowest standard error of calibration value of 0.81 and the highest R(2) value of 0.999. The model was further validated by quantitative analysis of commercial Kona coffee blends. Results demonstrate that FTIR can be a rapid alternative to authenticate Kona coffee, which only needs very quick and simple sample preparations.

  16. Study on Senna alata and its different extracts by Fourier transform infrared spectroscopy and two-dimensional correlation infrared spectroscopy

    Science.gov (United States)

    Adiana, M. A.; Mazura, M. P.

    2011-04-01

    Senna alata L. commonly known as candle bush belongs to the family of Fabaceae and the plant has been reported to possess anti-inflammatory, analgesic, laxative and antiplatelet-aggregating activity. In order to develop a rapid and effective analysis method for studying integrally the main constituents in the medicinal materials and their extracts, discriminating the extracts from different extraction process, comparing the categories of chemical constituents in the different extracts and monitoring the qualities of medicinal materials, we applied Fourier transform infrared spectroscopy (FT-IR) associated with second derivative infrared spectroscopy and two-dimensional infrared correlation spectroscopy (2D-IR) to study the main constituents of S. alata and its different extracts (extracted by hexane, dichloromethane, ethyl acetate and methanol in turn). The findings indicated that FT-IR and 2D-IR can provide many holistic variation rules of chemical constituents. Use of the macroscopical fingerprint characters of FT-IR and 2D-IR spectrum can identify the main chemical constituents in medicinal materials and their extracts, but also compare the components differences among similar samples. In a conclusion, FT-IR spectroscopy combined with 2D correlation analysis provides a powerful method for the quality control of traditional medicines.

  17. Protein folding and misfolding shining light by infrared spectroscopy

    CERN Document Server

    Fabian, Heinz

    2012-01-01

    Infrared spectroscopy is a new and innovative technology to study protein folding/misfolding events in the broad arsenal of techniques conventionally used in this field. The progress in understanding protein folding and misfolding is primarily due to the development of biophysical methods which permit to probe conformational changes with high kinetic and structural resolution. The most commonly used approaches rely on rapid mixing methods to initiate the folding event via a sudden change in solvent conditions. Traditionally, techniques such as fluorescence, circular dichroism or visible absorption are applied to probe the process. In contrast to these techniques, infrared spectroscopy came into play only very recently, and the progress made in this field up to date which now permits to probe folding events over the time scale from picoseconds to minutes has not yet been discussed in a book. The aim of this book is to provide an overview of the developments as seen by some of the main contributors to the field...

  18. Imperial College near infrared spectroscopy neuroimaging analysis framework.

    Science.gov (United States)

    Orihuela-Espina, Felipe; Leff, Daniel R; James, David R C; Darzi, Ara W; Yang, Guang-Zhong

    2018-01-01

    This paper describes the Imperial College near infrared spectroscopy neuroimaging analysis (ICNNA) software tool for functional near infrared spectroscopy neuroimaging data. ICNNA is a MATLAB-based object-oriented framework encompassing an application programming interface and a graphical user interface. ICNNA incorporates reconstruction based on the modified Beer-Lambert law and basic processing and data validation capabilities. Emphasis is placed on the full experiment rather than individual neuroimages as the central element of analysis. The software offers three types of analyses including classical statistical methods based on comparison of changes in relative concentrations of hemoglobin between the task and baseline periods, graph theory-based metrics of connectivity and, distinctively, an analysis approach based on manifold embedding. This paper presents the different capabilities of ICNNA in its current version.

  19. Reflective all-sky thermal infrared cloud imager.

    Science.gov (United States)

    Redman, Brian J; Shaw, Joseph A; Nugent, Paul W; Clark, R Trevor; Piazzolla, Sabino

    2018-04-30

    A reflective all-sky imaging system has been built using a long-wave infrared microbolometer camera and a reflective metal sphere. This compact system was developed for measuring spatial and temporal patterns of clouds and their optical depth in support of applications including Earth-space optical communications. The camera is mounted to the side of the reflective sphere to leave the zenith sky unobstructed. The resulting geometric distortion is removed through an angular map derived from a combination of checkerboard-target imaging, geometric ray tracing, and sun-location-based alignment. A tape of high-emissivity material on the side of the reflector acts as a reference that is used to estimate and remove thermal emission from the metal sphere. Once a bias that is under continuing study was removed, sky radiance measurements from the all-sky imager in the 8-14 μm wavelength range agreed to within 0.91 W/(m 2 sr) of measurements from a previously calibrated, lens-based infrared cloud imager over its 110° field of view.

  20. Investigation of Filtration Membranes from the Dairy Protein Industry for Residual Fouling Using Infrared Spectroscopy and Chemometrics

    DEFF Research Database (Denmark)

    Jensen, Jannie Krog

    the reversible fouling can be removed/cleaned. The aim of this thesis is to investigate the residual fouling that is deposited on ultrafiltration and microfiltration membranes after usage. The membrane surfaces are investigated using infrared spectroscopy with an attenuated reflectance sampling unit...... and this is thesis work highlights the strengths and weaknesses of using infrared spectroscopy to investigate residual fouling on membranes and in particular the challenges with the infrared penetration depth when layering in the samples occurs. Real size production membrane cartridges at different stages of use...... microfiltration membrane cartridges were investigated with Attenuated- Total-Reflection Fourier-Transform-Infrared (ATR FT-IR) to map the residual fouling on both types of cartridges. The height of the characteristic amide peaks from proteins were used to determine the relative concentrations. The first...

  1. Enhancing the Responsivity of Uncooled Infrared Detectors Using Plasmonics for High-Performance Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Amr Shebl Ahmed

    2017-04-01

    Full Text Available A lead zirconate titanate (PZT;Pb(Zr0.52Ti0.48O3 layer embedded infrared (IR detector decorated with wavelength-selective plasmonic crystals has been investigated for high-performance non-dispersive infrared (NDIR spectroscopy. A plasmonic IR detector with an enhanced IR absorption band has been designed based on numerical simulations, fabricated by conventional microfabrication techniques, and characterized with a broadly tunable quantum cascade laser. The enhanced responsivity of the plasmonic IR detector at specific wavelength band has improved the performance of NDIR spectroscopy and pushed the limit of detection (LOD by an order of magnitude. In this paper, a 13-fold enhancement in the LOD of a methane gas sensing using NDIR spectroscopy is demonstrated with the plasmonic IR detector.

  2. Practical guide to interpretive near-infrared spectroscopy

    CERN Document Server

    Workman, Jr, Jerry

    2007-01-01

    Containing focused, comprehensive coverage, Practical Guide to Interpretive Near-Infrared Spectroscopy gives you the tools necessary to interpret NIR spectra. The authors present extensive tables, charts, and figures with NIR absorption band assignments and structural information for a broad range of functional groups, organic compounds, and polymers. They include visual spectral representation of all major compound functional groupings and NIR frequency ranges. Organized by functional group type and chemical structure, based on standard compound classification, the chapters are easy to

  3. Core-shell particle composition by liquid phase infrared spectroscopy

    International Nuclear Information System (INIS)

    Ribeiro, Luiz F.B.; Machado, Ricardo A.F.; Goncalves, Odinei H.; Bona, Evandro

    2011-01-01

    Polymeric particles with core-shell morphology can offer advantages over conventional particles improving properties like mechanical and chemical resistance. However, particle composition must be known due to its influence on the final properties. In this work liquid phase infrared spectroscopy was used to determine the overall composition of core-shell particles composed by polystyrene (core) and poly(methyl methacrylate) (shell). Results were in agreement with those obtained with H 1 Nuclear Magnetic Resonance data (Goncalves et al, 2008). (author)

  4. Radiolysis of ferrocyanide solutions studied by infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Le Caer, S. [CEA/Saclay, DSM/DRECAM/SCM/URA 331 CNRS, F-91191Gif-sur-Yvette Cedex (France)]. E-mail: sophie.le-caer@cea.fr; Vigneron, G. [CEA/Saclay, DSM/DRECAM/SCM/URA 331 CNRS, F-91191Gif-sur-Yvette Cedex (France); Renault, J.P. [CEA/Saclay, DSM/DRECAM/SCM/URA 331 CNRS, F-91191Gif-sur-Yvette Cedex (France); Pommeret, S. [CEA/Saclay, DSM/DRECAM/SCM/URA 331 CNRS, F-91191Gif-sur-Yvette Cedex (France)

    2007-08-15

    The behavior of the neutral and basic aqueous ferrocyanide system under irradiation is investigated using the coupling of a LINAC with infrared spectroscopy. The comparison between the neutral and basic system evidences the formation of the hydroxopentacyanoferrate (III) ions and gives information on the reaction mechanisms. The pseudo-protective effect of the dissolved dioxygen on the ferrocyanide is explained via a mechanism implying the superoxide radical anion.

  5. Far-infrared ferroelectric soft mode spectroscopy on thin films

    Czech Academy of Sciences Publication Activity Database

    Petzelt, Jan; Ostapchuk, Tetyana

    2001-01-01

    Roč. 249, 1-2 (2001), s. 81-88 ISSN 0015-0193 R&D Projects: GA ČR GA202/98/1282; GA AV ČR IAA1010918; GA MŠk OC 514.10 Institutional research plan: CEZ:AV0Z1010914 Keywords : far-infrared spectroscopy * soft mode * dielectric spectra * permitivity Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.471, year: 2001

  6. Burned bones forensic investigations employing near infrared spectroscopy

    OpenAIRE

    Cascant, Mari Merce; Rubio, Sonia; Gallello, Gianni; Pastor, Agustin; Garrigues, Salvador; De la Guardia, Miguel

    2017-01-01

    The use of near infrared (NIR) spectroscopy was evaluated, by using chemometric tools, for the study of the environmental impact on burned bones. Spectra of internal and external parts of burned bones, together with sediment samples, were treated by Principal Component Analysis and cluster classification as exploratory techniques to select burned bone samples, less affected by environmental processes, to properly carry out forensic studies. Partial Least Square Discriminant Analysis was used ...

  7. [Near infrared spectroscopy study on water content in turbine oil].

    Science.gov (United States)

    Chen, Bin; Liu, Ge; Zhang, Xian-Ming

    2013-11-01

    Near infrared (NIR) spectroscopy combined with successive projections algorithm (SPA) was investigated for determination of water content in turbine oil. Through the 57 samples of different water content in turbine oil scanned applying near infrared (NIR) spectroscopy, with the water content in the turbine oil of 0-0.156%, different pretreatment methods such as the original spectra, first derivative spectra and differential polynomial least squares fitting algorithm Savitzky-Golay (SG), and successive projections algorithm (SPA) were applied for the extraction of effective wavelengths, the correlation coefficient (R) and root mean square error (RMSE) were used as the model evaluation indices, accordingly water content in turbine oil was investigated. The results indicated that the original spectra with different water content in turbine oil were pretreated by the performance of first derivative + SG pretreatments, then the selected effective wavelengths were used as the inputs of least square support vector machine (LS-SVM). A total of 16 variables selected by SPA were employed to construct the model of SPA and least square support vector machine (SPA-LS-SVM). There is 9 as The correlation coefficient was 0.975 9 and the root of mean square error of validation set was 2.655 8 x 10(-3) using the model, and it is feasible to determine the water content in oil using near infrared spectroscopy and SPA-LS-SVM, and an excellent prediction precision was obtained. This study supplied a new and alternative approach to the further application of near infrared spectroscopy in on-line monitoring of contamination such as water content in oil.

  8. Near-infrared spectroscopy and microstructure of the scales of Sabethes ( Sabethes albiprivus (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Betina Westphal-Ferreira

    Full Text Available ABSTRACT Near-infrared spectroscopy and microstructure of the scales of Sabethes (Sabethes albiprivus (Diptera: Culicidae. Sabethes (Sabethes albiprivus Theobald individuals vary considerably in size and color of the reflections of the scales on their thorax, abdomen, antepronotal lobes and occiput. The goal of this study was to investigate and to characterize the differences in the color of the scales among preserved specimens and to analyze the differences in the microstructures of the scales that cover their bodies using near-infrared spectroscopy, and to evaluate whether the latter is efficient in distinguishing the populations. A total of 201 adult females were analyzed for the characterization of color patterns. In addition, absorbance spectra and scanning electron microscope images were obtained from them. As a result of color analysis, two variations were identified, one represented by specimens with yellow or green scales and the other with blue or purple scales. The same two variations were corroborated using NIRS. Analysis of the microstructure of the scales lining the mesonotum, occiput and antepronotal lobes resulted in the same variations. The three methodologies, near-infrared spectroscopy, scanning electron microscopy and coloration of the reflections of the scales revealed two variations within Sa. albiprivus.

  9. Infrared reflectance measurement for InN thin film characterization

    International Nuclear Information System (INIS)

    Fukui, K.; Kugumiya, Y.; Nakagawa, N.; Yamamoto, A.

    2006-01-01

    Infrared reflectance measurements of a series of InN thin films have been performed and attempt to derive carrier concentration and other physical constants for InN thin film characterization. Fitting calculations are performed by use of the dielectric function equation based on phonon-plasmon coupling model. Longitudinal and transverse optical phonon frequencies, plasma frequency and their damping parameters can be derived from fitting. From those results, electrical and phonon properties of InN and characterization of films are discussed. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Final Technical Report - Polymeric Multilayer Infrared Reflecting Mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Reed, John [3M Company, St. Paul, MN (United States)

    2016-09-16

    The goal of this project was to develop a clear, polymeric, multilayer film with an expanded infrared (IR) reflection band which would allow improved rejection of incident IR energy. The IR reflection band is covering the region from about 850 nm to 1830 nm. This film is essentially clear and colorless in the visible portion of the electromagnetic spectra (visible light transmission of about 89%) while reflecting 90-95% of the IR energy over the portion of the spectra indicated above. This film has a nominal thickness of 3 mils, is polymeric in nature (contains no metals, metal oxides, or other material types) and is essentially clear in appearance This film can then be used as a component of other products such as a solar window film, an IR reflecting interlayer for laminated glass, a heat rejecting skylight film, a base film for daylight redirecting products, a greenhouse film, and many more applications. One of the main strengths of this product is that because it is a standalone IR rejecting film, it can be incorporated and retrofitted into many applications that desire or require the transmission of visible light, but want to block other portions of the solar spectra, especially the IR portion. Many of the applications exist in the window glazing product area where this film can provide for substantial energy improvements in applications where visible light is desired.

  11. Rapid identification of soil cadmium pollution risk at regional scale based on visible and near-infrared spectroscopy

    NARCIS (Netherlands)

    Chen, T.; Changa, Q.; Clevers, J.G.P.W.; Kooistra, L.

    2015-01-01

    Soil heavy metal pollution due to long-term sewage irrigation is a serious environmental problem in many irrigation areas in northern China. Quickly identifying its pollution status is an important basis for remediation. Visible-near-infrared reflectance spectroscopy (VNIRS) provides a useful tool.

  12. Short-Wavelength Infrared (SWIR) spectroscopy of low-grade metamorphic volcanic rocks of the Pilbara Craton

    NARCIS (Netherlands)

    Abweny, Mohammad S.; van Ruitenbeek, Frank J A; de Smeth, Boudewijn; Woldai, Tsehaie; van der Meer, Freek D.; Cudahy, Thomas; Zegers, Tanja; Blom, Jan Kees; Thuss, Barbara

    This paper shows the results of Short-Wavelength Infrared (SWIR) spectroscopy investigations of volcanic rocks sampled from low-grade metamorphic greenstone belts of the Archean Pilbara Craton in Western Australia. From the reflectance spectra a range of spectrally active minerals were identified,

  13. Infrared Spectroscopy of Noh Suspended in Solid Parahydrogen: Part Two

    Science.gov (United States)

    Balabanoff, Morgan E.; Mutunga, Fredrick M.; Anderson, David T.

    2015-06-01

    The only report in the literature on the infrared spectroscopy of the parent oxynitrene NOH was performed using Ar matrix isolation spectroscopy at 10 K. In this previous study, they performed detailed isotopic studies to make definitive vibrational assignments. NOH is predicted by high-level calculations to be in a triplet ground electronic state, but the Ar matrix isolation spectra cannot be used to verify this triplet assignment. In our 2013 preliminary report, we showed that 193 nm in situ photolysis of NO trapped in solid parahydrogen can also be used to prepare the NOH molecule. Over the ensuing two years we have been studying the infrared spectroscopy of this species in more detail. The spectra reveal that NOH can undergo hindered rotation in solid parahydrogen such that we can observe both a-type and b-type rovibrational transitions for the O-H stretch vibrational mode, but only a-type for the mode assigned to the bend. In addition, both observed a-type infrared absorption features (bend and OH stretch) display fine structure; an intense central peak with weaker peaks spaced symmetrically to both lower and higher wavenumbers. The spacing between the peaks is nearly identical for both vibrational modes. We now believe this fine structure is due to spin-rotation interactions and we will present a detailed analysis of this fine structure. Currently, we are performing additional experiments aimed at making 15NOH to test these preliminary assignments. The most recent data and up-to-date analysis will be presented in this talk. G. Maier, H. P. Reisenauer, M. De Marco, Angew. Chem. Int. Ed. 38, 108-110 (1999). U. Bozkaya, J. M. Turney, Y. Yamaguchi, and H. F. Schaefer III, J. Chem. Phys. 136, 164303 (2012). David T. Anderson and Mahmut Ruzi, 68th Ohio State University International Symposium on Molecular Spectroscopy, talk TE01 (2013).

  14. Advantages of infrared transflection micro spectroscopy and paraffin-embedded sample preparation for biological studies

    Science.gov (United States)

    Yao, Jie; Li, Qian; Zhou, Bo; Wang, Dan; Wu, Rie

    2018-04-01

    Fourier-Transform Infrared micro-spectroscopy is an excellent method for biological analyses. In this paper, series metal coating films on ITO glass were prepared by the electrochemical method and the different thicknesses of paraffin embedding rat's brain tissue on the substrates were studied by IR micro-spetroscopy in attenuated total reflection (ATR) mode and transflection mode respectively. The Co-Ni-Cu alloy coating film with low cost is good reflection substrates for the IR analysis. The infrared microscopic transflection mode needs not to touch the sample at all and can get the IR spectra with higher signal to noise ratios. The Paraffin-embedding method allows tissues to be stored for a long time for re-analysis to ensure the traceability of the sample. Also it isolates the sample from the metal and avoids the interaction of biological tissue with the metals. The best thickness of the tissues is 4 μm.

  15. Prediction of the Composition of Fresh Pastures by Near Infrared Reflectance or Interactance-Reflectance Spectroscopy Predicción de la composición de pradera fresca mediante espectroscopía de reflectancia o interactancia-reflectancia en el infrarrojo cercano

    Directory of Open Access Journals (Sweden)

    Daniel Alomar

    2009-06-01

    Full Text Available Fast and precise analytical tools can contribute to optimize pasture management decisions. This work was carried out to evaluate the potential of one such technique, near infrared spectroscopy (NIRS, to predict the nutritional value of pastures without previous drying of the samples, comparing two forms of collecting the spectra: reflectance, or interactance-reflectance (fiber optic probe. Samples (n = 107 from different swards were taken across the humid and temperate regions (Los Ríos and Los Lagos of southern Chile. Once their spectra were collected, dry matter (DM and several chemical constituents, such as crude protein (CP, metabolizable energy (ME, neutral (NDF and acid detergent fiber (ADF, soluble carbohydrates (SC, soluble crude protein (SCP and neutral detergent insoluble N (NDFIN, were determined as reference data. Calibrations were developed and the best ranked were selected (by cross-validation according to a lower standard error of cross validation (SE CV and a higher determination coefficient of cross validation (R²CV. Calibrations in the reflectance mode, for DM and CP, reached a high R²CV (0.99 and 0.91, respectively and a SE CV (6.5 and 18.4 g kg-1. Equations for ADF, SCP and ME were ranked next, with R²CV of 0.87, 0.84 and 0.82, respectively, and SE CV of 15.88 g kg-1, 15.45 g kg-1 and 0.34 Mj kg-1. Equations for NDF, SC and NDFIN, with R²CV of 0.78, 0.77 and 0.61, respectively, and SE CV of 35.57, 94.54 and 1.89 g kg-1, respectively, are considered unreliable for prediction purposes. Interactance-reflectance, on the other hand, resulted in poorer equations for all fractions.Disponer de técnicas bromatológicas rápidas y precisas ayudaría a optimizar decisiones en el manejo de praderas. En este trabajo se evaluó el potencial de una de tales técnicas, la espectroscopía de reflectancia en el infrarrojo cercano (NIRS para predecir el valor nutricional de praderas al estado fresco y comparar dos formas de colectar los

  16. Total reflection X-ray photoelectron spectroscopy: A review

    International Nuclear Information System (INIS)

    Kawai, Jun

    2010-01-01

    Total reflection X-ray photoelectron spectroscopy (TRXPS) is reviewed and all the published papers on TRXPS until the end of 2009 are included. Special emphasis is on the historical development. Applications are also described for each report. The background reduction is the most important effect of total reflection, but interference effect, relation to inelastic mean free path, change of probing depth are also discussed.

  17. Can infrared spectroscopy provide information on protein-protein interactions?

    Science.gov (United States)

    Haris, Parvez I

    2010-08-01

    For most biophysical techniques, characterization of protein-protein interactions is challenging; this is especially true with methods that rely on a physical phenomenon that is common to both of the interacting proteins. Thus, for example, in IR spectroscopy, the carbonyl vibration (1600-1700 cm(-1)) associated with the amide bonds from both of the interacting proteins will overlap extensively, making the interpretation of spectral changes very complicated. Isotope-edited infrared spectroscopy, where one of the interacting proteins is uniformly labelled with (13)C or (13)C,(15)N has been introduced as a solution to this problem, enabling the study of protein-protein interactions using IR spectroscopy. The large shift of the amide I band (approx. 45 cm(-1) towards lower frequency) upon (13)C labelling of one of the proteins reveals the amide I band of the unlabelled protein, enabling it to be used as a probe for monitoring conformational changes. With site-specific isotopic labelling, structural resolution at the level of individual amino acid residues can be achieved. Furthermore, the ability to record IR spectra of proteins in diverse environments means that isotope-edited IR spectroscopy can be used to structurally characterize difficult systems such as protein-protein complexes bound to membranes or large insoluble peptide/protein aggregates. In the present article, examples of application of isotope-edited IR spectroscopy for studying protein-protein interactions are provided.

  18. Mid-Infrared Frequency-Agile Dual-Comb Spectroscopy

    Science.gov (United States)

    Luo, Pei-Ling; Yan, Ming; Iwakuni, Kana; Millot, Guy; Hänsch, Theodor W.; Picqué, Nathalie

    2016-06-01

    We demonstrate a new approach to mid-infrared dual-comb spectroscopy. It opens up new opportunities for accurate real-time spectroscopic diagnostics and it significantly simplifies the technique of dual-comb spectroscopy. Two mid-infrared frequency combs of slightly different repetition frequencies and moderate, but rapidly tunable, spectral span are generated in the 2800-3200 cm-1 region. The generators rely on electro-optic modulators, nonlinear fibers for spectral broadening and difference frequency generation and do not involve mode-locked lasers. Flat-top frequency combs span up to 10 cm-1 with a comb line spacing of 100 MHz (3×10-3 cm-1). The performance of the spectrometer without any phase-lock electronics or correction scheme is illustrated with spectra showing resolved comb lines and Doppler-limited spectra of methane. High precision on the spectroscopic parameter (line positions and intensities) determination is demonstrated for spectra measured on a millisecond time scale and it is validated with comparison with literature data. G. Millot, S. Pitois, M. Yan, T. Hovannysyan, A. Bendahmane, T.W. Hänsch, N. Picqué, Frequency-agile dual-comb spectroscopy, Nature Photonics 10, 27-30 (2016).

  19. Photoacoustic-based detector for infrared laser spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, L.; Palzer, S., E-mail: stefan.palzer@imtek.uni-freiburg.de [Department of Microsystems Engineering-IMTEK, Laboratory for Gas Sensors, University of Freiburg, Georges-Köhler-Allee 102, Freiburg 79110 (Germany)

    2016-07-25

    In this contribution, we present an alternative detector technology for use in direct absorption spectroscopy setups. Instead of a semiconductor based detector, we use the photoacoustic effect to gauge the light intensity. To this end, the target gas species is hermetically sealed under excess pressure inside a miniature cell along with a MEMS microphone. Optical access to the cell is provided by a quartz window. The approach is particularly suitable for tunable diode laser spectroscopy in the mid-infrared range, where numerous molecules exhibit large absorption cross sections. Moreover, a frequency standard is integrated into the method since the number density and pressure inside the cell are constant. We demonstrate that the information extracted by our method is at least equivalent to that achieved using a semiconductor-based photon detector. As exemplary and highly relevant target gas, we have performed direct spectroscopy of methane at the R3-line of the 2v{sub 3} band at 6046.95 cm{sup −1} using both detector technologies in parallel. The results may be transferred to other infrared-active transitions without loss of generality.

  20. Surface enhanced infrared spectroscopy using interacting gold nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Neubrech, Frank; Weber, Daniel; Pucci, Annemarie [Kirchhoff-Institut fuer Physik, Heidelberg (Germany); Shen, Hong [Universite Troyes, Troyes (France); Lamy de la Chapelle, Marc [Universite Paris 13, Bobigny (France)

    2009-07-01

    We performed surface enhanced infrared spectroscopy (SEIRS) of molecules adsorbed on gold nanowires using synchrotron light of the ANKA IR-beamline at the Forschungszentrum Karlsruhe (Germany). Arrays of gold nanowires with interparticle spacings down to 30nm were prepared by electron beam lithography. The interparticle distance was reduced further by wet-chemically increasing the size of the gold nanowires. The growth of the wires was proofed using IR spectroscopy as well as scanning electron microscopy. After this preparation step, appropriate arrays of nanowires with an interparticle distance down to a few nanometers were selected to demonstrate the surface enhanced infrared spectroscopy of one monolayer octadecanthiol (ODT). As know from SEIRS studies using single gold nanowires, the spectral position of the antenna-like resonance in relation to the absorption bands of ODT (2850cm-1 and 2919cm-1) is crucial for both, the lineshape of the molecular vibration and the signal enhancement. In contrast to single nanowires studies, a further increase of the enhanced signals is expected due to the interaction of the electromagnetic fields of the close-by nanowires.

  1. Vibrational Spectroscopy of Intramolecular Hydrogen Bonds in the Infrared and Near-Infrared Regions

    DEFF Research Database (Denmark)

    Schrøder, Sidsel Dahl

    and 1,4-diaminobutane). Experimentally, the hydrogen bonds have been studied with vibrational spectroscopy in the infrared and near-infrared regions. The focus is primarily on spectra recorded in the near-infrared regions, which in these studies are dominated by O-H and N-H stretching overtones....... Overtone spectra have been recorded with intracavity laser photoacoustic laser spectroscopy and conventional long path absorption spectroscopy. Theoretically, a combination of electronic structure calculations and local mode models have been employed to guide the assignment of bands in the vibrational......,4-diaminobutane, no sign of intramolecular N-H···N hydrogen bonds were identified in the overtone spectra. However, theoretical analyzes indicate that intramolecular N-H···N hydrogen bonds are present in all three diamines if two hydrogen atoms on one of the methylene groups are substituted with triuoromethyl...

  2. [Application of near-infrared spectroscopy in golf turfgrass management].

    Science.gov (United States)

    Li, Shu-Ying; Han, Jian-Guo

    2008-07-01

    The management of golf course is different from other turfs. Its particularity lies in its higher and more precise requirement during maintenance compare with other turfs. In case something happened to turf of golf course, more effective and higher speed detecting and resolution are required. Only the data about turf growth and environment were mastered precisely in time, the friendly environmental and scientific management goal could be completed effectively and economically. The near infrared spectroscopy is a new kind of effective, convenient and non-destructive analytical method in the turfgrass management of golf course in recent years. Many factors of turf-soil system in golf course could be determined by near infrared spectroscopy at the same time. In this paper, the existing literature that use of near infrared spectroscopy to study turfgrass and soil nutrient content, soil hygroscopic moisture, feasible fertilizer application time and rate, to fix the time and volume of irrigation, turfgrass visual quality evaluation, turfgrass disease prediction and prevention were reviewed. Most researchers considered the nutrition condition of turf impacted the visual and playing quality of golf course directly and then indirectly influenced most of assistant cultivation such as fertilization, mowing and irrigation and so on. The using of NIRS can detect the nutrient content of turfgrass effectively and estimate the nutrient is excessive or deficient quickly. And then the feasible time and rate of fertilizers can be decided. Comparing with the common judgment ways based on the season fertilization and visual estimation, the using of NIRS can reduce the application of fertilizers on the base of keeping the same turf quality simultaneously. NIRS can analysis many items of soil such as moisture, elements concentration, textures on the spot by the thousands. This method can get lots of cover-all data non-destructively. What's more, NIRS can analysis soil betimes quickly

  3. Neuroimaging with functional near infrared spectroscopy: From formation to interpretation

    Science.gov (United States)

    Herrera-Vega, Javier; Treviño-Palacios, Carlos G.; Orihuela-Espina, Felipe

    2017-09-01

    Functional Near Infrared Spectroscopy (fNIRS) is gaining momentum as a functional neuroimaging modality to investigate the cerebral hemodynamics subsequent to neural metabolism. As other neuroimaging modalities, it is neuroscience's tool to understand brain systems functions at behaviour and cognitive levels. To extract useful knowledge from functional neuroimages it is critical to understand the series of transformations applied during the process of the information retrieval and how they bound the interpretation. This process starts with the irradiation of the head tissues with infrared light to obtain the raw neuroimage and proceeds with computational and statistical analysis revealing hidden associations between pixels intensities and neural activity encoded to end up with the explanation of some particular aspect regarding brain function.To comprehend the overall process involved in fNIRS there is extensive literature addressing each individual step separately. This paper overviews the complete transformation sequence through image formation, reconstruction and analysis to provide an insight of the final functional interpretation.

  4. Instrumentation for Reflectance Spectroscopy and Microspectroscopy with Application to Astrobiology

    Science.gov (United States)

    Mouroulis, Pantazis; Blaney, Diana L.; Green, Robert O.

    2008-01-01

    We present instrument concepts for in-situ reflectance spectroscopy over a spatial resolution range from several meters to tens of micrometers. These have been adapted to the low mass and power requirements of rover or similar platforms. Described are a miniaturized imaging spectrometer for rover mast, a combined mast and arm point spectrometer, and an imaging microspectrometer for the rover arm.

  5. Sensing cocaine in saliva with infrared laser spectroscopy

    Science.gov (United States)

    Hans, Kerstin M.-C.; Müller, Matthias; Gianella, Michele; Wägli, Ph.; Sigrist, Markus W.

    2013-02-01

    Increasing numbers of accidents caused by drivers under the influence of drugs, raise drug tests to worldwide interest. We developed a one-step extraction technique for cocaine in saliva and analyzed reference samples with laser spectroscopy employing two different schemes. The first is based on attenuated total reflection (ATR), which is applied to dried samples. The second scheme uses transmission measurements for the analysis of liquid samples. ATR spectroscopy achieved a limit of detection (LOD) of 3μg/ml. The LOD for the transmission approach in liquid samples is cocaine. An improved stabilization of the set-up should lower the limit of detection significantly.

  6. Development of infrared spectroscopy techniques for environmental monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sandsten, Jonas

    2000-08-01

    Infrared spectroscopy techniques have long been utilized in identifying and quantifying species of interest to us. Many of the elementary molecules in the atmosphere interact with infrared radiation through their ability to absorb and emit energy in vibrational and rotational transitions. A large variety of methods for monitoring of molecules and aerosol particles by collecting samples or by using remote sensing methods are available. The objective of the work presented in this thesis was to develop infrared spectroscopic techniques to further enhance the amount of useful information obtained from gathering spectral data. A new method for visualization and quantification of gas flows based on gas-correlation techniques was developed. Real-time imaging of gas leaks and incomplete or erratic flare combustion of ethene was demonstrated. The method relies on the thermal background as a radiation source and the gas can be visualized in absorption or in emission depending on the temperature difference. Diode laser spectroscopy was utilized to monitor three molecular species at the same time and over the same path. Two near-infrared diode lasers beams were combined in a periodically poled lithium niobate crystal and by difference-frequency generation a third beam was created, enabling simultaneous monitoring of oxygen, water vapor and methane. Models of aerosol particle cross sections were used to simulate the diffraction pattern of light scattered by fibers, spherical particles and real particles, such as pollen, through a new aerosol particle sensing prototype. The instrument, using a coupled cavity diode laser, has been designed with a ray-tracing program and the final prototype was employed for single aerosol particle sizing and identification.

  7. Near-infrared spectroscopy. Innovative technology summary report

    International Nuclear Information System (INIS)

    1999-07-01

    A near-infrared (NIR) spectroscopy system with a remote fiber-optic probe was developed and demonstrated to measure the water content of high-level radioactive wastes from the underground storage tanks at the Hanford Site in richland Washington. The technology was developed as a cost-effective and safer alternative to the thermogravimetric analysis (TGA) technique in use as the baseline. This work was supported by the Tanks Focus Area (TFA) within the Department of Energy's (DOE) Office of Science and Technology (OST) in cooperation with the Hanford Tank Waste Remediation System (TWRS) Program

  8. Optical characterization of semiconductors infrared, Raman, and photoluminescence spectroscopy

    CERN Document Server

    Perkowitz, Sidney

    1993-01-01

    This is the first book to explain, illustrate, and compare the most widely used methods in optics: photoluminescence, infrared spectroscopy, and Raman scattering. Written with non-experts in mind, the book develops the background needed to understand the why and how of each technique, but does not require special knowledge of semiconductors or optics. Each method is illustrated with numerous case studies. Practical information drawn from the authors experience is given to help establish optical facilities, including commercial sources for equipment, and experimental details. For industrial sci

  9. Exploring process dynamics by near infrared spectroscopy in lactic fermentations

    DEFF Research Database (Denmark)

    Svendsen, Carina; Cieplak, Tomasz; van der Berg, Franciscus Winfried J

    2016-01-01

    In the industrial production of yoghurt, measurement of pH is normally the only in-line technique applied as a real-time monitoring signalfor following the dynamics during the fermentation process. However, every dairy company would benefit from an in-line technique giving information about...... the chemical composition, physical/textural properties and/or microbial contamination. In this study lactic fermentation batches with the starter bacteria Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus are explored by in-line near infrared (NIR) spectroscopy. The dynamics obtained...

  10. Gum Arabic authentication and mixture quantification by near infrared spectroscopy

    DEFF Research Database (Denmark)

    Dong, Yongjiang; Sørensen, Klavs Martin; He, Sailing

    2017-01-01

    A rapid and reliable method is developed for Gum Arabic authentication based on Near Infrared (NIR) spectroscopy and chemometric methods. On a large industrial collection of authentic gum Arabics, the two major Acacia gum species, Acacia senegal and Acacia seyal could be assigned perfectly...... by the NIR spectroscopic method. In addition, a partial least squares (PLS) regression model is calibrated to predict the blending percentage of the two pure gum types, producing an accuracy, root mean square error of cross validation (RMSECV) of 2.8%. Sampling of the Gum Arabic ‘tears’ is discussed......, and it was determined that subsamples from three ‘tears’ is required for a representative result. It is concluded that NIR spectroscopy is a very powerful and reliable method for authenticity testing of Gum Arabic species....

  11. Usefulness of portable near infrared spectroscopy in olive breeding programs

    Energy Technology Data Exchange (ETDEWEB)

    Leon-Moreno, L.

    2012-11-01

    The usefulness of portable near infrared (NIR) spectroscopy as a simple and efficient method to determine some of the main selection traits in olive breeding is evaluated in this work. Calibration models were developed and evaluated using partial least squares (PLS) regression from samples collected in different selection steps of the breeding work and under different experimental conditions. The results showed that accurate enough models (values of correlation between actual and predicted constituent higher than 0.9) were obtained for oil and moisture content in both cross validation and prediction results. Portable NIR spectroscopy could be used for selection of genotypes on the basis of these characters, providing similar ranking of genotypes than reference methods both in different selection steps of the breeding process (progenies and selection plots) and different experimental conditions (on-tree or under laboratory conditions). The advantages of this technique to improve the efficiency of the evaluation process in olive breeding programs are discussed. (Author) 21 refs.

  12. Near infrared spectroscopy in the development of solid dosage forms.

    Science.gov (United States)

    Räsänen, Eetu; Sandler, Niklas

    2007-02-01

    The use of near infrared (NIR) spectroscopy has rapidly grown partly due to demands of process analytical applications in the pharmaceutical industry. Furthermore, newest regulatory guidelines have advanced the increase of the use of NIR technologies. The non-destructive and non-invasive nature of measurements makes NIR a powerful tool in characterization of pharmaceutical solids. These benefits among others often make NIR advantageous over traditional analytical methods. However, in addition to NIR, a wide variety of other tools are naturally also available for analysis in pharmaceutical development and manufacturing, and those can often be more suitable for a given application. The versatility and rapidness of NIR will ensure its contribution to increased process understanding, better process control and improved quality of drug products. This review concentrates on the use of NIR spectroscopy from a process research perspective and highlights recent applications in the field.

  13. Two-dimensional infrared spectroscopy of vibrational polaritons.

    Science.gov (United States)

    Xiang, Bo; Ribeiro, Raphael F; Dunkelberger, Adam D; Wang, Jiaxi; Li, Yingmin; Simpkins, Blake S; Owrutsky, Jeffrey C; Yuen-Zhou, Joel; Xiong, Wei

    2018-04-19

    We report experimental 2D infrared (2D IR) spectra of coherent light-matter excitations--molecular vibrational polaritons. The application of advanced 2D IR spectroscopy to vibrational polaritons challenges and advances our understanding in both fields. First, the 2D IR spectra of polaritons differ drastically from free uncoupled excitations and a new interpretation is needed. Second, 2D IR uniquely resolves excitation of hybrid light-matter polaritons and unexpected dark states in a state-selective manner, revealing otherwise hidden interactions between them. Moreover, 2D IR signals highlight the impact of molecular anharmonicities which are applicable to virtually all molecular systems. A quantum-mechanical model is developed which incorporates both nuclear and electrical anharmonicities and provides the basis for interpreting this class of 2D IR spectra. This work lays the foundation for investigating phenomena of nonlinear photonics and chemistry of molecular vibrational polaritons which cannot be probed with traditional linear spectroscopy.

  14. Species authentication and geographical origin discrimination of herbal medicines by near infrared spectroscopy: A review

    OpenAIRE

    Wang, Pei; Yu, Zhiguo

    2015-01-01

    Near infrared (NIR) spectroscopy as a rapid and nondestructive analytical technique, integrated with chemometrics, is a powerful process analytical tool for the pharmaceutical industry and is becoming an attractive complementary technique for herbal medicine analysis. This review mainly focuses on the recent applications of NIR spectroscopy in species authentication of herbal medicines and their geographical origin discrimination. Keywords: Near infrared spectroscopy, Herbal medicine, Species...

  15. Near-infrared laboratory spectroscopy of mineral chemistry: A review

    Science.gov (United States)

    Meer, Freek van der

    2018-03-01

    Spectroscopy is the science concerned with the investigation and measurement of spectra produced when materials interacts with or emits electromagnetic radiation. Commercial infrared spectrometer were designed from the 1950's onward and found their way into the pharmaceutical and chemical industries. In the 1970's and 1980's also natural sciences notably mineralogy and vegetation science started systematically to measure optical properties of leaves and minerals/rocks with spectrometers. In the last decade spectroscopy has made the step from qualitative observations of mineral classes, soil type and vegetation biomass to quantitative estimates of mineral, soil and vegetation chemistry. This resulted in geothermometers used to characterize metamorphic and hydrothermal systems and to the advent of foliar biochemistry. More research is still needed to bridge the gap between laboratory spectroscopy and field spectroscopy. Empirical studies of minerals either as soil or rock constituents (and vegetation parameters) derived from regression analysis of spectra against chemistry is important in understanding the physics of the interaction of electromagnetic radiation and matter which in turn is important in the design of future satellite missions. Physics based models and retrievals are needed to operationalize these relationships and implement them in future earth observation missions as these are more robust and easy to transfer to other areas and data sets.

  16. Chemometric analysis of attenuated total reflectance infrared spectra of Proteus mirabilis strains with defined structures of LPS.

    Science.gov (United States)

    Zarnowiec, Paulina; Mizera, Andrzej; Chrapek, Magdalena; Urbaniak, Mariusz; Kaca, Wieslaw

    2016-07-01

    Proteus spp. strains are some of the most important pathogens associated with complicated urinary tract infections and bacteremia affecting patients with immunodeficiency and long-term urinary catheterization. For epidemiological purposes, various molecular typing methods have been developed for this pathogen. However, these methods are labor intensive and time consuming. We evaluated a new method of differentiation between strains. A collection of Proteus spp. strains was analyzed by attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy in the mid-infrared region. ATR FT-IR spectroscopy used in conjunction with a diamond ATR accessory directly produced the biochemical profile of the surface chemistry of bacteria. We conclude that a combination of ATR FT-IR spectroscopy and mathematical modeling provides a fast and reliable alternative for discrimination between Proteus isolates, contributing to epidemiological research. © The Author(s) 2016.

  17. Differentiation and quality estimation of Cordyceps with infrared spectroscopy

    Science.gov (United States)

    Yang, Ping; Song, Ping; Sun, Su-Qin; Zhou, Qun; Feng, Shu; Tao, Jia-Xun

    2009-11-01

    Heretofore, a scientific and systemic method for differentiation and quality estimation of a well-known Chinese traditional medicine, 'Cordyceps', has not been established in modern market. In this paper, Fourier-transform infrared spectroscopy (FTIR) and two-dimensional correlation infrared spectroscopy (2D-IR) are employed to propose a method for analysis of Cordyceps. It has presented that IR spectra of real Cordyceps of different origins and counterfeits have their own macroscopic fingerprints, with discriminated shapes, positions and intensities. Their secondary derivative spectra can amplify the differences and confirm the potentially characteristic IR absorption bands 1400-1700 cm -1 to be investigated in 2D-IR. Many characteristic fingerprints are discovered in 2D-IR spectra in the range of 1400-1700 cm -1 and hetero 2D spectra of 670-780 cm -1 × 1400-1700 cm -1. The different fingerprints display different chemical constitutes. Through the three steps, different Cordyceps and their counterfeits can be discriminated effectively and their qualities distinctly display. Successful analysis of eight Cordyceps capsule products has proved the practicability of the method, which can also be applied to the quality estimation of other Chinese traditional medicines.

  18. Optical Fiber Sensing Based on Reflection Laser Spectroscopy

    Directory of Open Access Journals (Sweden)

    Gianluca Gagliardi

    2010-03-01

    Full Text Available An overview on high-resolution and fast interrogation of optical-fiber sensors relying on laser reflection spectroscopy is given. Fiber Bragg-gratings (FBGs and FBG resonators built in fibers of different types are used for strain, temperature and acceleration measurements using heterodyne-detection and optical frequency-locking techniques. Silica fiber-ring cavities are used for chemical sensing based on evanescent-wave spectroscopy. Various arrangements for signal recovery and noise reduction, as an extension of most typical spectroscopic techniques, are illustrated and results on detection performances are presented.

  19. Fringes in FTIR spectroscopy revisited: understanding and modelling fringes in infrared spectroscopy of thin films.

    Science.gov (United States)

    Konevskikh, Tatiana; Ponossov, Arkadi; Blümel, Reinhold; Lukacs, Rozalia; Kohler, Achim

    2015-06-21

    The appearance of fringes in the infrared spectroscopy of thin films seriously hinders the interpretation of chemical bands because fringes change the relative peak heights of chemical spectral bands. Thus, for the correct interpretation of chemical absorption bands, physical properties need to be separated from chemical characteristics. In the paper at hand we revisit the theory of the scattering of infrared radiation at thin absorbing films. Although, in general, scattering and absorption are connected by a complex refractive index, we show that for the scattering of infrared radiation at thin biological films, fringes and chemical absorbance can in good approximation be treated as additive. We further introduce a model-based pre-processing technique for separating fringes from chemical absorbance by extended multiplicative signal correction (EMSC). The technique is validated by simulated and experimental FTIR spectra. It is further shown that EMSC, as opposed to other suggested filtering methods for the removal of fringes, does not remove information related to chemical absorption.

  20. Infrared spectroscopy of molecular submonolayers on surfaces by infrared scanning tunneling microscopy: tetramantane on Au111.

    Science.gov (United States)

    Pechenezhskiy, Ivan V; Hong, Xiaoping; Nguyen, Giang D; Dahl, Jeremy E P; Carlson, Robert M K; Wang, Feng; Crommie, Michael F

    2013-09-20

    We have developed a new scanning-tunneling-microscopy-based spectroscopy technique to characterize infrared (IR) absorption of submonolayers of molecules on conducting crystals. The technique employs a scanning tunneling microscope as a precise detector to measure the expansion of a molecule-decorated crystal that is irradiated by IR light from a tunable laser source. Using this technique, we obtain the IR absorption spectra of [121]tetramantane and [123]tetramantane on Au(111). Significant differences between the IR spectra for these two isomers show the power of this new technique to differentiate chemical structures even when single-molecule-resolved scanning tunneling microscopy (STM) images look quite similar. Furthermore, the new technique was found to yield significantly better spectral resolution than STM-based inelastic electron tunneling spectroscopy, and to allow determination of optical absorption cross sections. Compared to IR spectroscopy of bulk tetramantane powders, infrared scanning tunneling microscopy (IRSTM) spectra reveal narrower and blueshifted vibrational peaks for an ordered tetramantane adlayer. Differences between bulk and surface tetramantane vibrational spectra are explained via molecule-molecule interactions.

  1. Infrared spectroscopy for geologic interpretation of TIMS data

    Science.gov (United States)

    Bartholomew, Mary Jane

    1986-01-01

    The Portable Field Emission Spectrometer (PFES) was designed to collect meaningful spectra in the field under climatic, thermal, and sky conditions that approximate those at the time of the overflight. The specifications and procedures of PFES are discussed. Laboratory reflectance measurements of rocks and minerals were examined for the purpose of interpreting Thermal Infrared Multispectral Scanner (TIMS) data. The capability is currently being developed to perform direct laboratory measurement of the normal spectral radiance of Earth surface materials at low temperatures (20 to 30 C) at the Jet Propulsion Laboratory.

  2. Application of attenuated total reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR) in MIR range coupled with chemometrics for detection of pig body fat in pure ghee (heat clarified milk fat)

    Science.gov (United States)

    Upadhyay, Neelam; Jaiswal, Pranita; Jha, Shyam Narayan

    2018-02-01

    Pure ghee is superior to other fats and oils due to the presence of bioactive lipids and its rich flavor. Adulteration of ghee with cheaper fats and oils is a prevalent fraudulent practice. ATR-FTIR spectroscopy was coupled with chemometrics for the purpose of detection of presence of pig body fat in pure ghee. Pure mixed ghee was spiked with pig body fat @ 3, 4, 5, 10, 15% level. The spectra of pure (ghee and pig body fat) along with the spiked samples was taken in MIR from 4000 to 500 cm-1. Some wavenumber ranges were selected on the basis of differences in the spectra obtained. Separate clusters of the samples were obtained by employing principal component analysis at 5% level of significance on the selected wavenumber range. Probable class membership was predicted by applying SIMCA approach. Approximately, 90% of the samples classified into their respective class and pure ghee and pig body fat never misclassified themselves. The value of R2 was >0.99 for both calibration and validation sets using partial least square method. The study concluded that spiking of pig body fat in pure ghee can be detected even at a level of 3%.

  3. Electrochemical and Infrared Absorption Spectroscopy Detection of SF₆ Decomposition Products.

    Science.gov (United States)

    Dong, Ming; Zhang, Chongxing; Ren, Ming; Albarracín, Ricardo; Ye, Rixin

    2017-11-15

    Sulfur hexafluoride (SF₆) gas-insulated electrical equipment is widely used in high-voltage (HV) and extra-high-voltage (EHV) power systems. Partial discharge (PD) and local heating can occur in the electrical equipment because of insulation faults, which results in SF₆ decomposition and ultimately generates several types of decomposition products. These SF₆ decomposition products can be qualitatively and quantitatively detected with relevant detection methods, and such detection contributes to diagnosing the internal faults and evaluating the security risks of the equipment. At present, multiple detection methods exist for analyzing the SF₆ decomposition products, and electrochemical sensing (ES) and infrared (IR) spectroscopy are well suited for application in online detection. In this study, the combination of ES with IR spectroscopy is used to detect SF₆ gas decomposition. First, the characteristics of these two detection methods are studied, and the data analysis matrix is established. Then, a qualitative and quantitative analysis ES-IR model is established by adopting a two-step approach. A SF₆ decomposition detector is designed and manufactured by combining an electrochemical sensor and IR spectroscopy technology. The detector is used to detect SF₆ gas decomposition and is verified to reliably and accurately detect the gas components and concentrations.

  4. Assessment of hyaline cartilage matrix composition using near infrared spectroscopy.

    Science.gov (United States)

    Palukuru, Uday P; McGoverin, Cushla M; Pleshko, Nancy

    2014-09-01

    Changes in the composition of the extracellular matrix (ECM) are characteristic of injury or disease in cartilage tissue. Various imaging modalities and biochemical techniques have been used to assess the changes in cartilage tissue but lack adequate sensitivity, or in the case of biochemical techniques, result in destruction of the sample. Fourier transform near infrared (FT-NIR) spectroscopy has shown promise for the study of cartilage composition. In the current study NIR spectroscopy was used to identify the contributions of individual components of cartilage in the NIR spectra by assessment of the major cartilage components, collagen and chondroitin sulfate, in pure component mixtures. The NIR spectra were obtained using homogenous pellets made by dilution with potassium bromide. A partial least squares (PLS) model was calculated to predict composition in bovine cartilage samples. Characteristic absorbance peaks between 4000 and 5000 cm(-1) could be attributed to components of cartilage, i.e. collagen and chondroitin sulfate. Prediction of the amount of collagen and chondroitin sulfate in tissues was possible within 8% (w/dw) of values obtained by gold standard biochemical assessment. These results support the use of NIR spectroscopy for in vitro and in vivo applications to assess matrix composition of cartilage tissues, especially when tissue destruction should be avoided. Copyright © 2014. Published by Elsevier B.V.

  5. In situ observation of surface reactions with synchrotron radiation induced semiconductor processes by infrared reflection absorption spectroscopy using buried metal layer substrates; Umekomi kinzokuso kiban wo mochiita sekigai hansha kyushu supekutoruho ni yoru hoshako reiki handotai process hanno no sonoba kansatsu

    Energy Technology Data Exchange (ETDEWEB)

    Yoshigoe, A.; Hirano, S. [The Graduate University for Advanced Studies, Yokohama (Japan); Mase, K.; Urisu, T. [Institute for Molecular Science, Aichi (Japan)

    1996-11-20

    It is known that infrared reflection absorption spectroscopy (IRAS) on semiconductor or insulator surfaces becomes practicable by using buried metal layer (BML) substrates, in which the metal thin film is buried order semiconductor or insulator films. In this work, IRAS has been measured for Langmuir-Blodgett films deposited on the BML substrate with SiO2/Al/Si(100) structure and the observed spectrum intensity has been quantitatively compared with the calculation assuming the ideal multilayer structure for the BML substrate. The BML-IRAS using CoSi2 has been adopted to the detection of SiHn on the Si (100) substrate during synchrotron radiation (SR) stimulated Si2H6 gas source molecular beam epitaxy. It has been found that SiH2 and SiH3 on the Si (100) surface are easily decomposed by SR, but SiH can`t be decomposed. From these experiments, it has been concluded that the BML-IRAS is an useful in situ observation technique for the photo-stimulated surface reactions. 26 refs., 9 figs.

  6. Quantitative Determination of Germinability of Puccinia striiformis f. sp. tritici Urediospores Using Near Infrared Spectroscopy Technology

    Directory of Open Access Journals (Sweden)

    Yaqiong Zhao

    2015-01-01

    Full Text Available 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.

  7. [Study on predicting sugar content and valid acidity of apples by near infrared diffuse reflectance technique].

    Science.gov (United States)

    Liu, Yan-de; Ying, Yi-bin; Fu, Xia-ping

    2005-11-01

    The nondestructive method for quantifying sugar content (SC) and available acid (VA) of intact apples using diffuse near infrared reflectance and optical fiber sensing techniques were explored in the present research. The standard sample sets and prediction models were established by partial least squares analysis (PLS). A total of 120 Shandong Fuji apples were tested in the wave number of 12,500 - 4000 cm(-1) using Fourier transform near infrared spectroscopy. The results of the research indicated that the nondestructive quantification of SC and VA, gave a high correlation coefficient 0.970 and 0.906, a low root mean square error of prediction (RMSEP) 0.272 and 0.056 2, a low root mean square error of calibration (RMSEC) 0.261 and 0.0677, and a small difference between RMSEP and RMSEC 0.011 a nd 0.0115. It was suggested that the diffuse nearinfrared reflectance technique be feasible for nondestructive determination of apple sugar content in the wave number range of 10,341 - 5461 cm(-1) and for available acid in the wave number range of 10,341 - 3818 cm(-1).

  8. Infrared spectroscopy with multivariate analysis to interrogate endometrial tissue: a novel and objective diagnostic approach.

    Science.gov (United States)

    Taylor, S E; Cheung, K T; Patel, I I; Trevisan, J; Stringfellow, H F; Ashton, K M; Wood, N J; Keating, P J; Martin-Hirsch, P L; Martin, F L

    2011-03-01

    Endometrial cancer is the most common gynaecological malignancy in the United Kingdom. Diagnosis currently involves subjective expert interpretation of highly processed tissue, primarily using microscopy. Previous work has shown that infrared (IR) spectroscopy can be used to distinguish between benign and malignant cells in a variety of tissue types. Tissue was obtained from 76 patients undergoing hysterectomy, 36 had endometrial cancer. Slivers of endometrial tissue (tumour and tumour-adjacent tissue if present) were dissected and placed in fixative solution. Before analysis, tissues were thinly sliced, washed, mounted on low-E slides and desiccated; 10 IR spectra were obtained per slice by attenuated total reflection Fourier-transform IR (ATR-FTIR) spectroscopy. Derived data was subjected to principal component analysis followed by linear discriminant analysis. Post-spectroscopy analyses, tissue sections were haematoxylin and eosin-stained to provide histological verification. Using this approach, it is possible to distinguish benign from malignant endometrial tissue, and various subtypes of both. Cluster vector plots of benign (verified post-spectroscopy to be free of identifiable pathology) vs malignant tissue indicate the importance of the lipid and secondary protein structure (Amide I and Amide II) regions of the spectrum. These findings point towards the possibility of a simple objective test for endometrial cancer using ATR-FTIR spectroscopy. This would facilitate earlier diagnosis and so reduce the morbidity and mortality associated with this disease.

  9. NIRS - Near infrared spectroscopy - investigations in neurovascular diseases

    DEFF Research Database (Denmark)

    Schytz, Henrik Winther

    2015-01-01

    The purpose of this thesis was to explore and develop methods, where continuous wave near infrared spectroscopy (CW-NIRS) can be applied in different neurovascular diseases, in order to find biological markers that are useful in clinical neurology. To develop a new method to detect changes...... tomography (133Xe-SPECT) and the corrected BFI value. It was concluded, that it was not possible to obtain reliable BFI data with the ICG CW-NIRS method. NIRS measurements of low frequency oscillations (LFOs) may be a reliable method to investigate vascular alterations in neurovascular diseases......, but this requires an acceptable LFOs variation between hemispheres and over time in the healthy brain. The second study therefore investigated day-to-day and hemispheric variations in LFOs with NIRS. It was shown that NIRS might be useful in assessing LFOs between hemispheres, as well as interhemispheric phase...

  10. Near-infrared spectroscopy (NIRS) in a piglet model

    DEFF Research Database (Denmark)

    Clausen, Nicola Groes; Spielmann, Nelly; Ringer, Simone K.

    2017-01-01

    Near-infrared spectroscopy (NIRS) in a piglet model: readings are influenced by the colour of the cover Clausen NG1,2, Spielmann N1,3, Weiss M1,3, Ringer SK4 1Children’s Research Center, University Children’s Hospital of Zurich, Switzerland; 2Department of Anaesthesiology and Intensive Care, Odense....... The rSO2 was measured by placing NIRS sensors in the supra glabellar region. In 12 animals sensors were covered with a uni-coloured pink (P) napkin and a turquoise (T) napkin in a random order (Setting A). In further 13 animals sensors were covered with blue-coloured surgical drape (SD) and a napkin...... with a reddish SantaClaus (SC) motive (Setting B). Uncovered (UC) baseline values were captured and measurements obtained for a period of three minutes. During measurements, the animals were kept in normoterm, normotensive, normoglycaemic and normoxic condition. Inspired oxygen fraction and ventilatory settings...

  11. Measuring protein dynamics with ultrafast two-dimensional infrared spectroscopy

    International Nuclear Information System (INIS)

    Adamczyk, Katrin; Candelaresi, Marco; Hunt, Neil T; Robb, Kirsty; Hoskisson, Paul A; Tucker, Nicholas P; Gumiero, Andrea; Walsh, Martin A; Parker, Anthony W

    2012-01-01

    Recent advances in the methodology and application of ultrafast two-dimensional infrared (2D-IR) spectroscopy to biomolecular systems are reviewed. A description of the 2D-IR technique and the molecular contributions to the observed spectra are presented followed by a discussion of recent literature relating to the use of 2D-IR and associated approaches for measuring protein dynamics. In particular, these include the use of diatomic ligand groups for measuring haem protein dynamics, isotopic labelling strategies and the use of vibrational probe groups. The final section reports on the current state of the art regarding the use of 2D-IR methods to provide insights into biological reaction mechanisms. (topical review)

  12. Demonstration of a Fast, Precise Propane Measurement Using Infrared Spectroscopy

    Science.gov (United States)

    Zahniser, M. S.; Roscioli, J. R.; Nelson, D. D.; Herndon, S. C.

    2016-12-01

    Propane is one of the primary components of emissions from natural gas extraction and processing activities. In addition to being an air pollutant, its ratio to other hydrocarbons such as methane and ethane can serve as a "fingerprint" of a particular facility or process, aiding in identifying emission sources. Quantifying propane has typically required laboratory analysis of flask samples, resulting in low temporal resolution and making plume-based measurements infeasible. Here we demonstrate fast (1-second), high precision (infrared spectroscopy at 2967 wavenumbers. In addition, we explore the impact of nearby water and ethane absorption lines on the accuracy and precision of the propane measurement. Finally, we discuss development of a dual-laser instrument capable of simultaneous measurements of methane, ethane, and propane (the C1-C3 compounds), all within a small spatial package that can be easily deployed aboard a mobile platform.

  13. Mid-infrared spectroscopy for characterization of Baltic amber (succinite)

    Science.gov (United States)

    Wagner-Wysiecka, Ewa

    2018-05-01

    Natural Baltic amber (succinite) is the most appreciated fossil resin of the rich cultural traditions dating back to prehistoric times. Its unequivocal identification is extremely important in many branches of science and trades including archeology, paleontology, chemistry and finally mineralogical and gemological societies. Current methods of modification of natural succinite are more and more sophisticated making the identification of natural Baltic amber often challenging. In article the systematic analytical approach for identification of natural and modified under different conditions succinite, using mid-infrared spectroscopy (transmission, Drifts and ATR techniques) is presented. The correlation between spectral characteristics and properties of succinite is discussed pointing that the understanding of the nature of changes is the key of identification of this precious material.

  14. A rheumatoid arthritis study by Fourier transform infrared spectroscopy

    Science.gov (United States)

    Carvalho, Carolina S.; Silva, Ana Carla A.; Santos, Tatiano J. P. S.; Martin, Airton A.; dos Santos Fernandes, Ana Célia; Andrade, Luís E.; Raniero, Leandro

    2012-01-01

    Rheumatoid arthritis is a systemic inflammatory disease of unknown causes and a new methods to identify it in early stages are needed. The main purpose of this work is the biochemical differentiation of sera between normal and RA patients, through the establishment of a statistical method that can be appropriately used for serological analysis. The human sera from 39 healthy donors and 39 rheumatics donors were collected and analyzed by Fourier Transform Infrared Spectroscopy. The results show significant spectral variations with p<0.05 in regions corresponding to protein, lipids and immunoglobulins. The technique of latex particles, coated with human IgG and monoclonal anti-CRP by indirect agglutination known as FR and CRP, was performed to confirm possible false-negative results within the groups, facilitating the statistical interpretation and validation of the technique.

  15. Infrared spectroscopy for monitoring gas hydrates in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Dobbs, G.T.; Luzinova, Y.; Mizaikoff, B. [Georgia Inst. of Technology, Atlanta, GA (United States). School of Chemistry and Biochemistry; Raichlin, Y.; Katzir, A. [Tel-Aviv Univ., Tel-Aviv (Israel). Shool of Physics and Astronomy

    2008-07-01

    This paper introduced the first principles for monitoring gas hydrate formation and dissociation in aqueous solution by evaluating state-responsive infrared (IR) absorption features of water with fiberoptic evanescent field spectroscopy. A first order linear functional relationship was also derived according to Lambert Beer's law in order to quantify the percentage gas hydrate within the volume of water probed via the evanescent field. In addition, spectroscopic studies evaluating seafloor sediments collected from a gas hydrate site in the Gulf of Mexico revealed minimal spectral interferences from sediment matrix components. As such, evanescent field sensing strategies were established as a promising perspective for monitoring the dynamics of gas hydrates in oceanic environments. 21 refs., 5 figs.

  16. Infrared Absorption Spectroscopy and Chemical Kinetics of Free Radicals

    Energy Technology Data Exchange (ETDEWEB)

    Curl, Robert F; Glass, Graham

    2004-11-01

    This research was directed at the detection, monitoring, and study of the chemical kinetic behavior by infrared absorption spectroscopy of small free radical species thought to be important intermediates in combustion. Work on the reaction of OH with acetaldehyde has been completed and published and work on the reaction of O({sup 1}D) with CH{sub 4} has been completed and submitted for publication. In the course of our investigation of branching ratios of the reactions of O({sup 1}D) with acetaldehyde and methane, we discovered that hot atom chemistry effects are not negligible at the gas pressures (13 Torr) initially used. Branching ratios of the reaction of O({sup 1}D) with CH{sub 4} have been measured at a tenfold higher He flow and fivefold higher pressure.

  17. Brain plasticity and rehabilitation by using Near-Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Balconi Michela

    2016-04-01

    Full Text Available The present review elucidated the use of optical imaging technique (Near-Infrared Spectroscopy, NIRS to better explain the brain plasticity for learning mechanisms, rehabilitation and post-traumatic brain recovery. Some recent applications were discussed, with specific focus on the usability of integrated measures (such as electroencephalography, EEG-NIRS; Transcranial Magnet Stimulation, TMS-NIRS to study plasticity and its dynamic effects. NIRS-Neurofeedback and NIRS-BCI (Brain Computer Interface were also explored as possible tools to produce a specific long-lasting learning in relationship with a specific cognitive domain. Finally a proficient domain where NIRS was found to be useful to test neuroplasticity is the interpersonal brain-to-brain coupling, termed “hyperscanning”, a new emerging paradigm in neuroscience which measures brain activity from two or more people simultaneously.

  18. Near-infrared Spectroscopy in the Brewing Industry.

    Science.gov (United States)

    Sileoni, Valeria; Marconi, Ombretta; Perretti, Giuseppe

    2015-01-01

    This article offers an exhaustive description of the use of Near-Infrared (NIR) Spectroscopy in the brewing industry. This technique is widely used for quality control testing of raw materials, intermediates, and finished products, as well as process monitoring during malting and brewing. In particular, most of the reviewed works focus on the assessment of barley properties, aimed at quickly selecting the best barley varieties in order to produce a high-quality malt leading to high-quality beer. Various works concerning the use of NIR in the evaluation of raw materials, such as barley, malt, hop, and yeast, are also summarized here. The implementation of NIR sensors for the control of malting and brewing processes is also highlighted, as well as the use of NIR for quality assessment of the final product.

  19. Functional near-infrared spectroscopy studies in children

    Directory of Open Access Journals (Sweden)

    Nagamitsu Shinichiro

    2012-03-01

    Full Text Available Abstract Psychosomatic and developmental behavioral medicine in pediatrics has been the subject of significant recent attention, with infants, school-age children, and adolescents frequently presenting with psychosomatic, behavioral, and psychiatric symptoms. These may be a consequence of insecurity of attachment, reduced self-confidence, and peer -relationship conflicts during their developmental stages. Developmental cognitive neuroscience has revealed significant associations between specific brain lesions and particular cognitive dysfunctions. Thus, identifying the biological deficits underlying such cognitive dysfunction may provide new insights into therapeutic prospects for the management of those symptoms in children. Recent advances in noninvasive neuroimaging techniques, and especially functional near-infrared spectroscopy (NIRS, have contributed significant findings to the field of developmental cognitive neuroscience in pediatrics. We present here a comprehensive review of functional NIRS studies of children who have developed normally and of children with psychosomatic and behavioral disorders.

  20. Near-infrared spectroscopy for monitoring muscle oxygenation

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Piantadosi, C A

    2000-01-01

    Near-infrared spectroscopy (NIRS) is a non-invasive method for monitoring oxygen availability and utilization by the tissues. In intact skeletal muscle, NIRS allows semi-quantitative measurements of haemoglobin plus myoglobin oxygenation (tissue O2 stores) and the haemoglobin volume. Specialized...... algorithms allow assessment of the oxidation-reduction (redox) state of the copper moiety (CuA) of mitochondrial cytochrome c oxidase and, with the use of specific tracers, accurate assessment of regional blood flow. NIRS has demonstrated utility for monitoring changes in muscle oxygenation and blood flow...... during submaximal and maximal exercise and under pathophysiological conditions including cardiovascular disease and sepsis. During work, the extent to which skeletal muscles deoxygenate varies according to the type of muscle, type of exercise and blood flow response. In some instances, a strong...

  1. Infrared spectroscopy and microscopy in cancer research and diagnosis

    Science.gov (United States)

    Bellisola, Giuseppe; Sorio, Claudio

    2012-01-01

    Since the middle of 20th century infrared (IR) spectroscopy coupled to microscopy (IR microspectroscopy) has been recognized as a non destructive, label free, highly sensitive and specific analytical method with many potential useful applications in different fields of biomedical research and in particular cancer research and diagnosis. Although many technological improvements have been made to facilitate biomedical applications of this powerful analytical technique, it has not yet properly come into the scientific background of many potential end users. Therefore, to achieve those fundamental objectives an interdisciplinary approach is needed with basic scientists, spectroscopists, biologists and clinicians who must effectively communicate and understand each other's requirements and challenges. In this review we aim at illustrating some principles of Fourier transform (FT) Infrared (IR) vibrational spectroscopy and microscopy (microFT-IR) as a useful method to interrogate molecules in specimen by mid-IR radiation. Penetrating into basics of molecular vibrations might help us to understand whether, when and how complementary information obtained by microFT-IR could become useful in our research and/or diagnostic activities. MicroFT-IR techniques allowing to acquire information about the molecular composition and structure of a sample within a micrometric scale in a matter of seconds will be illustrated as well as some limitations will be discussed. How biochemical, structural, and dynamical information about the systems can be obtained by bench top microFT-IR instrumentation will be also presented together with some methods to treat and interpret IR spectral data and applicative examples. The mid-IR absorbance spectrum is one of the most information-rich and concise way to represent the whole “… omics” of a cell and, as such, fits all the characteristics for the development of a clinically useful biomarker. PMID:22206042

  2. Optimal hemodynamic response model for functional near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Muhammad Ahmad Kamran

    2015-06-01

    Full Text Available Functional near-infrared spectroscopy (fNIRS is an emerging non-invasive brain imaging technique and measures brain activities by means of near-infrared light of 650-950 nm wavelengths. The cortical hemodynamic response (HR differs in attributes at different brain regions and on repetition of trials, even if the experimental paradigm is kept exactly the same. Therefore, an HR model that can estimate such variations in the response is the objective of this research. The canonical hemodynamic response function (cHRF is modeled by using two Gamma functions with six unknown parameters. The HRF model is supposed to be linear combination of HRF, baseline and physiological noises (amplitudes and frequencies of physiological noises are supposed to be unknown. An objective function is developed as a square of the residuals with constraints on twelve free parameters. The formulated problem is solved by using an iterative optimization algorithm to estimate the unknown parameters in the model. Inter-subject variations in HRF and physiological noises have been estimated for better cortical functional maps. The accuracy of the algorithm has been verified using ten real and fifteen simulated data sets. Ten healthy subjects participated in the experiment and their HRF for finger-tapping tasks have been estimated and analyzed. The statistical significance of the estimated activity strength parameters has been verified by employing statistical analysis, i.e., (t-value >tcritical and p-value < 0.05.

  3. Pulsed near-infrared photoacoustic spectroscopy of blood

    Science.gov (United States)

    Laufer, Jan G.; Elwell, Clare E.; Delpy, Dave T.; Beard, Paul C.

    2004-07-01

    The aim of this study was to use pulsed near infrared photoacoustic spectroscopy to determine the oxygen saturation (SO2) of a saline suspension of red blood cells in vitro. The photoacoustic measurements were made in a cuvette which formed part of a larger circuit through which the red blood cell suspension was circulated. Oxygen saturation of the red blood cell suspension was altered between 2-3% to 100% in step increments using a membrane oxygenator and at each increment an independent measurement of oxygen saturation was made using a co-oximeter. An optical parametric oscillator laser system provided nanosecond excitation pulses at a number of wavelengths in the near-infrared spectrum (740-1040nm) which were incident on the cuvette. The resulting acoustic signals were detected using a broadband (15MHz) Fabry-Perot polymer film transducer. The optical transport coefficient and amplitude were determined from the acoustic signals as a function of wavelength. These data were then used to calculate the relative concentrations of oxy- and deoxyhaemoglobin, using their known specific absorption coefficients and an empirically determined wavelength dependence of optical scattering over the wavelength range investigated. From this, the oxygen saturation of the suspension was derived with an accuracy of +/-5% compared to the co-oximeter SO2 measurements.

  4. Recent Developments in Solid-Phase Extraction for Near and Attenuated Total Reflection Infrared Spectroscopic Analysis

    Directory of Open Access Journals (Sweden)

    Christian W. Huck

    2016-05-01

    Full Text Available A review with more than 100 references on the principles and recent developments in the solid-phase extraction (SPE prior and for in situ near and attenuated total reflection (ATR infrared spectroscopic analysis is presented. New materials, chromatographic modalities, experimental setups and configurations are described. Their advantages for fast sample preparation for distinct classes of compounds containing different functional groups in order to enhance selectivity and sensitivity are discussed and compared. This is the first review highlighting both the fundamentals of SPE, near and ATR spectroscopy with a view to real sample applicability and routine analysis. Most of real sample analyses examples are found in environmental research, followed by food- and bioanalysis. In this contribution a comprehensive overview of the most potent SPE-NIR and SPE-ATR approaches is summarized and provided.

  5. Use of photoacoustic mid-infrared spectroscopy to characterize soil properties and soil organic matter stability

    Science.gov (United States)

    Peltre, Clement; Bruun, Sander; Du, Changwen; Stoumann Jensen, Lars

    2014-05-01

    The persistence of soil organic matter (SOM) is recognized as a major ecosystem property due to its key role in earth carbon cycling, soil quality and ecosystem services. SOM stability is typically studied using biological methods such as measuring CO2-C evolution from microbial decomposition of SOM during laboratory incubation or by physical or chemical fractionation methods, allowing the separation of a labile fraction of SOM. However these methods are time consuming and there is still a need for developing reliable techniques to characterize SOM stability, providing both quantitative measurements and qualitative information, in order to improve our understanding of the mechanisms controlling SOM persistence. Several spectroscopic techniques have been used to characterize and predict SOM stability, such as near infrared reflectance spectroscopy (NIRS) and diffuse reflectance mid-infrared spectroscopy (DRIFT). The latter allows a proper identification of spectral regions corresponding to vibrations of specific molecular or functional groups associated with SOM lability. However, reflectance spectroscopy for soil analyses raises some difficulties related to the low reflectance of soils, and to the high influence of particle size. In the last three decades, the progresses in microphone sensitivity dramatically increased the performance of photoacoustic Fourier transform mid-infrared spectroscopy (FTIR-PAS). This technique offers benefits over reflectance spectroscopy techniques, because particle size and the level of sample reflectance have little effect of on the PAS signal, since FTIR-PAS is a direct absorption technique. Despite its high potential for soil analysis, only a limited number of studies have so far applied FTIR-PAS for soil characterization and its potential for determining SOM degradability still needs to be investigated. The objective of this study was to assess the potential of FTIR-PAS for the characterization of SOM decomposability during

  6. Infrared spectroscopy: a tool for determination of the degree of conversion in dental composites

    Directory of Open Access Journals (Sweden)

    Luciene Gonçalves Palmeira Moraes

    2008-04-01

    Full Text Available Infrared spectroscopy is one of the most widely used techniques for measurement of conversion degree in dental composites. However, to obtain good quality spectra and quantitative analysis from spectral data, appropriate expertise and knowledge of the technique are mandatory. This paper presents important details to use infrared spectroscopy for determination of the conversion degree.

  7. Near-Infrared Spatially Resolved Spectroscopy for Tablet Quality Determination.

    Science.gov (United States)

    Igne, Benoît; Talwar, Sameer; Feng, Hanzhou; Drennen, James K; Anderson, Carl A

    2015-12-01

    Near-infrared (NIR) spectroscopy has become a well-established tool for the characterization of solid oral dosage forms manufacturing processes and finished products. In this work, the utility of a traditional single-point NIR measurement was compared with that of a spatially resolved spectroscopic (SRS) measurement for the determination of tablet assay. Experimental designs were used to create samples that allowed for calibration models to be developed and tested on both instruments. Samples possessing a poor distribution of ingredients (highly heterogeneous) were prepared by under-blending constituents prior to compaction to compare the analytical capabilities of the two NIR methods. The results indicate that SRS can provide spatial information that is usually obtainable only through imaging experiments for the determination of local heterogeneity and detection of abnormal tablets that would not be detected with single-point spectroscopy, thus complementing traditional NIR measurement systems for in-line, and in real-time tablet analysis. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  8. Near-infrared spectroscopy for cocrystal screening. A comparative study with Raman spectroscopy.

    Science.gov (United States)

    Allesø, Morten; Velaga, Sitaram; Alhalaweh, Amjad; Cornett, Claus; Rasmussen, Morten A; van den Berg, Frans; de Diego, Heidi Lopez; Rantanen, Jukka

    2008-10-15

    Near-infrared (NIR) spectroscopy is a well-established technique for solid-state analysis, providing fast, noninvasive measurements. The use of NIR spectroscopy for polymorph screening and the associated advantages have recently been demonstrated. The objective of this work was to evaluate the analytical potential of NIR spectroscopy for cocrystal screening using Raman spectroscopy as a comparative method. Indomethacin was used as the parent molecule, while saccharin and l-aspartic acid were chosen as guest molecules. Molar ratios of 1:1 for each system were subjected to two types of preparative methods. In the case of saccharin, liquid-assisted cogrinding as well as cocrystallization from solution resulted in a stable 1:1 cocrystalline phase termed IND-SAC cocrystal. For l-aspartic acid, the solution-based method resulted in a polymorphic transition of indomethacin into the metastable alpha form retained in a physical mixture with the guest molecule, while liquid-assisted cogrinding did not induce any changes in the crystal lattice. The good chemical peak selectivity of Raman spectroscopy allowed a straightforward interpretation of sample data by analyzing peak positions and comparing to those of pure references. In addition, Raman spectroscopy provided additional information on the crystal structure of the IND-SAC cocrystal. The broad spectral line shapes of NIR spectra make visual interpretation of the spectra difficult, and consequently, multivariate modeling by principal component analysis (PCA) was applied. Successful use of NIR/PCA was possible only through the inclusion of a set of reference mixtures of parent and guest molecules representing possible solid-state outcomes from the cocrystal screening. The practical hurdle related to the need for reference mixtures seems to restrict the applicability of NIR spectroscopy in cocrystal screening.

  9. Advanced multivariate data evaluation for Fourier transform infrared spectroscopy

    International Nuclear Information System (INIS)

    Diewok, J.

    2002-12-01

    The objective of the presented dissertation was the evaluation, application and further development of advanced multivariate data evaluation methods for qualitative and quantitative Fourier transform infrared (FT-IR) measurements, especially of aqueous samples. The focus was set on 'evolving systems'; i.e. chemical systems that change gradually with a master variable, such as pH, reaction time, elution time, etc. and that are increasingly encountered in analytical chemistry. FT-IR measurements on such systems yield 2-way and 3-way data sets, i.e. data matrices and cubes. The chemometric methods used were soft-modeling techniques, like multivariate curve resolution - alternating least squares (MCR-ALS) or principal component analysis (PCA), hard modeling of equilibrium systems and two-dimensional correlation spectroscopy (2D-CoS). The research results are presented in six publications and comprise: A new combination of FT-IR flow titrations and second-order calibration by MCR-ALS for the quantitative analysis of mixture samples of organic acids and sugars. A novel combination of MCR-ALS with a hard-modeled equilibrium constraint for second-order quantitation in pH-modulated samples where analytes and interferences show very similar acid-base behavior. A detailed study in which MCR-ALS and 2D-CoS are directly compared for the first time. From the analysis of simulated and experimental acid-base equilibrium systems, the performance and interpretability of the two methods is evaluated. Investigation of the binding process of vancomycin, an important antibiotic, to a cell wall analogue tripeptide by time-resolved FT-IR spectroscopy and detailed chemometric evaluation. Determination of red wine constituents by liquid chromatography with FT-IR detection and MCR-ALS for resolution of overlapped peaks. Classification of red wine cultivars from FT-IR spectroscopy of phenolic wine extracts with hierarchical clustering and soft independent modeling of class analogy (SIMCA

  10. Role of Infrared Spectroscopy and Imaging in Cancer Diagnosis.

    Science.gov (United States)

    Kumar, Saroj; Srinivasan, Alagiri; Nikolajeff, Fredrik

    2018-01-01

    Cancer is a major global health issue. It causes extensive individual suffering and gives a huge burden on the health care in society. Despite extensive research and different tools have been developed it still remains a challenge for early detection of this disease. FTIR imaging has been used to diagnose and differentiate the molecular differences between normal and diseased tissues. Fourier Transform Infrared Spectroscopy (FTIR) is able to measure biochemical changes in tissue, cell and biofluids based on the vibrational signature of their components. This technique enables to the distribution and structure of lipids, proteins, nucleic acids as well as other metabolites. These differences depended on the type and the grade of cancer. We emphasize here, that the FTIR spectroscopy and imaging can be considered as a promising technique and will find its place on the detection of this dreadful disease because of high sensitivity, accuracy and inexpensive technique. Now the medical community started using and accepting this technique for early stage cancer detection. We discussed this technique and the several challenges in its application for the diagnosis of cancer in regards of sample preparations, data interpretation, and data analysis. The sensitivity of chemotherapy drugs on individual specific has also discussed. So far progressed has done with the FTIR imaging in understanding of cancer disease pathology. However, more research is needed in this field and it is necessary to understand the morphology and biology of the sample before using the spectroscopy and imaging because invaluable information to be figured out. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  11. Infrared

    Science.gov (United States)

    Vollmer, M.

    2013-11-01

    techniques such as attenuated total reflectance [6]. The two final papers deal with what seem to be wholly different scientific fields [7, 8]. One paper describes SOFIA, an aeroplane-based astronomical observatory covering the whole IR range [7], while the other represents a small review of the quite new topic of terahertz physics at the upper end of the IR spectral range, from around 30 µm to 3 mm wavelength, and its many applications in science and industry [8]. Although artificially separated, all these fields use similar kinds of detectors, similar kinds of IR sources and similar technologies, while the instruments use the same physical principles. We are convinced that the field of infrared physics will develop over the next decade in the same dynamic way as during the last, and this special issue may serve as starting point for regular submissions on the topic. At any rate, it shines a light on this fascinating and many-faceted subject, which started more than 200 years ago. References [1] Mangold K, Shaw J A and Vollmer M 2013 The physics of near-infrared photography Eur. J. Phys. 34 S51-71 [2] Vollmer M and Möllmann K-P 2013 Characterization of IR cameras in student labs Eur. J. Phys. 34 S73-90 [3] Ibarra-Castanedo C, Tarpani J R and Maldague X P V 2013 Nondestructive testing with thermography Eur. J. Phys. 34 S91-109 [4] Shaw J A and Nugent P W 2013 Physics principles in radiometric infrared imaging of clouds in the atmosphere Eur. J. Phys. 34 S111-21 [5] Möllmann K-P and Vollmer M 2013 Fourier transform infrared spectroscopy in physics laboratory courses Eur. J. Phys. 34 S123-37 [6] Heise H M, Fritzsche J, Tkatsch H, Waag F, Karch K, Henze K, Delbeck S and Budde J 2013 Recent advances in mid- and near-infrared spectroscopy with applications for research and teaching, focusing on petrochemistry and biotechnology relevant products Eur. J. Phys. 34 S139-59 [7] Krabbe A, Mehlert D, Röser H-P and Scorza C 2013 SOFIA, an airborne observatory for infrared astronomy

  12. High-speed high-sensitivity infrared spectroscopy using mid-infrared swept lasers (Conference Presentation)

    Science.gov (United States)

    Childs, David T. D.; Groom, Kristian M.; Hogg, Richard A.; Revin, Dmitry G.; Cockburn, John W.; Rehman, Ihtesham U.; Matcher, Stephen J.

    2016-03-01

    Infrared spectroscopy is a highly attractive read-out technology for compositional analysis of biomedical specimens because of its unique combination of high molecular sensitivity without the need for exogenous labels. Traditional techniques such as FTIR and Raman have suffered from comparatively low speed and sensitivity however recent innovations are challenging this situation. Direct mid-IR spectroscopy is being speeded up by innovations such as MEMS-based FTIR instruments with very high mirror speeds and supercontinuum sources producing very high sample irradiation levels. Here we explore another possible method - external cavity quantum cascade lasers (EC-QCL's) with high cavity tuning speeds (mid-IR swept lasers). Swept lasers have been heavily developed in the near-infrared where they are used for non-destructive low-coherence imaging (OCT). We adapt these concepts in two ways. Firstly by combining mid-IR quantum cascade gain chips with external cavity designs adapted from OCT we achieve spectral acquisition rates approaching 1 kHz and demonstrate potential to reach 100 kHz. Secondly we show that mid-IR swept lasers share a fundamental sensitivity advantage with near-IR OCT swept lasers. This makes them potentially able to achieve the same spectral SNR as an FTIR instrument in a time x N shorter (N being the number of spectral points) under otherwise matched conditions. This effect is demonstrated using measurements of a PDMS sample. The combination of potentially very high spectral acquisition rates, fundamental SNR advantage and the use of low-cost detector systems could make mid-IR swept lasers a powerful technology for high-throughput biomedical spectroscopy.

  13. Application of short-wave infrared (SWIR) spectroscopy in quantitative estimation of clay mineral contents

    International Nuclear Information System (INIS)

    You, Jinfeng; Xing, Lixin; Pan, Jun; Meng, Tao; Liang, Liheng

    2014-01-01

    Clay minerals are significant constituents of soil which are necessary for life. This paper studied three types of clay minerals, kaolinite, illite, and montmorillonite, for they are not only the most common soil forming materials, but also important indicators of soil expansion and shrinkage potential. These clay minerals showed diagnostic absorption bands resulting from vibrations of hydroxyl groups and structural water molecules in the SWIR wavelength region. The short-wave infrared reflectance spectra of the soil was obtained from a Portable Near Infrared Spectrometer (PNIS, spectrum range: 1300∼2500 nm, interval: 2 nm). Due to the simplicity, quickness, and the non-destructiveness analysis, SWIR spectroscopy has been widely used in geological prospecting, chemical engineering and many other fields. The aim of this study was to use multiple linear regression (MLR) and partial least squares (PLS) regression to establish the optimizing quantitative estimation models of the kaolinite, illite and montmorillonite contents from soil reflectance spectra. Here, the soil reflectance spectra mainly refers to the spectral reflectivity of soil (SRS) corresponding to the absorption-band position (AP) of kaolinite, illite, and montmorillonite representative spectra from USGS spectral library, the SRS corresponding to the AP of soil spectral and soil overall spectrum reflectance values. The optimal estimation models of three kinds of clay mineral contents showed that the retrieval accuracy was satisfactory (Kaolinite content: a Root Mean Square Error of Calibration (RMSEC) of 1.671 with a coefficient of determination (R 2 ) of 0.791; Illite content: a RMSEC of 1.126 with a R 2 of 0.616; Montmorillonite content: a RMSEC of 1.814 with a R 2 of 0.707). Thus, the reflectance spectra of soil obtained form PNIS could be used for quantitative estimation of kaolinite, illite and montmorillonite contents in soil

  14. Applicability of a Diffuse Reflectance Infrared Fourier Transform handheld spectrometer to perform in situ analyses on Cultural Heritage materials.

    Science.gov (United States)

    Arrizabalaga, Iker; Gómez-Laserna, Olivia; Aramendia, Julene; Arana, Gorka; Madariaga, Juan Manuel

    2014-08-14

    This work studies the applicability of a Diffuse Reflectance Infrared Fourier Transform handheld device to perform in situ analyses on Cultural Heritage assets. This portable diffuse reflectance spectrometer has been used to characterise and diagnose the conservation state of (a) building materials of the Guevara Palace (15th century, Segura, Basque Country, Spain) and (b) different 19th century wallpapers manufactured by the Santa Isabel factory (Vitoria-Gasteiz, Basque Country, Spain) and by the well known Dufour and Leroy manufacturers (Paris, France), all of them belonging to the Torre de los Varona Castle (Villanañe, Basque Country, Spain). In all cases, in situ measurements were carried out and also a few samples were collected and measured in the laboratory by diffuse reflectance spectroscopy (DRIFT) in order to validate the information obtained by the handheld instrument. In the analyses performed in situ, distortions in the diffuse reflectance spectra can be observed due to the presence of specular reflection, showing the inverted bands caused by the Reststrahlen effect, in particular on those IR bands with the highest absorption coefficients. This paper concludes that the results obtained in situ by a diffuse reflectance handheld device are comparable to those obtained with laboratory diffuse reflectance spectroscopy equipment and proposes a few guidelines to acquire good spectra in the field, minimising the influence caused by the specular reflection. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Surface analysis by Fourier-transform infrared (FTIR) spectroscopy

    International Nuclear Information System (INIS)

    Powell, G.L.; Smyrl, N.R.; Fuller, E.L.

    1981-01-01

    A diffuse-reflectance capability for the Fourier transform infrared spectrometer at the Y-12 Plant Laboratory has been implemented. A sample cell with a 25 to 400 0 C temperature-controlled sample stage and an ultrahigh-vacuum-to-atmospheric pressure gas-handling capability has been developed. Absorbance of light from the spectrometer beam, resulting from the beam being scattered from a powder sample, can be measured. This capability of detecting molecular species on and in powders is to be used to study chemisorption on actinide and rare-earth metals, alloys, and compounds. Cell design is described along with experiments demonstrating its performance in detecting moisture absorption on uranium oxide, moisture and carbon dioxide absorption on the lithium hydride/hydroxide system, and carbon dioxide absorption on potassium borohydride. 13 figures

  16. Mechanistic Insights into Growth of Surface‐Mounted Metal‐Organic Framework Films Resolved by Infrared (Nano‐) Spectroscopy

    OpenAIRE

    Delen, Guusje; Ristanović, Zoran; Mandemaker, Laurens D. B.; Weckhuysen, Bert M.

    2017-01-01

    Abstract Control over assembly, orientation, and defect‐free growth of metal‐organic framework (MOF) films is crucial for their future applications. A layer‐by‐layer approach is considered a suitable method to synthesize highly oriented films of numerous MOF topologies, but the initial stages of the film growth remain poorly understood. Here we use a combination of infrared (IR) reflection absorption spectroscopy and atomic force microscopy (AFM)‐IR imaging to investigate the assembly and gro...

  17. Terahertz time-domain transmission and reflection spectroscopy of niobium

    International Nuclear Information System (INIS)

    Hong, Tae Yoon; Choi, Kyu Jin; Park, Byoung Cheol; Ha, Tae Woo; Sim, Kyung Ik; Kim, Jea Hoon; Ha, Dong Gwang; Chang, Yonuk

    2013-01-01

    We have developed a terahertz time-domain spectroscopy (THz-TDS) system for transmission and reflection measurements of metallic thin films. Using our THz-TDS system, we studied the conventional superconductor niobium (Nb) in the normal state in the spectral range from 5 to 50 cm -1 . Both the real and imaginary parts of the conductivity are acquired without Kramers-Kronig analysis. Nb exhibits a nearly frequency independent real conductivity spectrum in the terahertz range, with a very small imaginary part.

  18. Infrared Reflectance Analysis of Epitaxial n-Type Doped GaN Layers Grown on Sapphire.

    Science.gov (United States)

    Tsykaniuk, Bogdan I; Nikolenko, Andrii S; Strelchuk, Viktor V; Naseka, Viktor M; Mazur, Yuriy I; Ware, Morgan E; DeCuir, Eric A; Sadovyi, Bogdan; Weyher, Jan L; Jakiela, Rafal; Salamo, Gregory J; Belyaev, Alexander E

    2017-12-01

    Infrared (IR) reflectance spectroscopy is applied to study Si-doped multilayer n + /n 0 /n + -GaN structure grown on GaN buffer with GaN-template/sapphire substrate. Analysis of the investigated structure by photo-etching, SEM, and SIMS methods showed the existence of the additional layer with the drastic difference in Si and O doping levels and located between the epitaxial GaN buffer and template. Simulation of the experimental reflectivity spectra was performed in a wide frequency range. It is shown that the modeling of IR reflectance spectrum using 2 × 2 transfer matrix method and including into analysis the additional layer make it possible to obtain the best fitting of the experimental spectrum, which follows in the evaluation of GaN layer thicknesses which are in good agreement with the SEM and SIMS data. Spectral dependence of plasmon-LO-phonon coupled modes for each GaN layer is obtained from the spectral dependence of dielectric of Si doping impurity, which is attributed to compensation effects by the acceptor states.

  19. Species authentication and geographical origin discrimination of herbal medicines by near infrared spectroscopy: A review

    Directory of Open Access Journals (Sweden)

    Pei Wang

    2015-10-01

    Full Text Available Near infrared (NIR spectroscopy as a rapid and nondestructive analytical technique, integrated with chemometrics, is a powerful process analytical tool for the pharmaceutical industry and is becoming an attractive complementary technique for herbal medicine analysis. This review mainly focuses on the recent applications of NIR spectroscopy in species authentication of herbal medicines and their geographical origin discrimination. Keywords: Near infrared spectroscopy, Herbal medicine, Species authentication, Geographical origin discrimination, Quality control

  20. Optimal hemodynamic response model for functional near-infrared spectroscopy.

    Science.gov (United States)

    Kamran, Muhammad A; Jeong, Myung Yung; Mannan, Malik M N

    2015-01-01

    Functional near-infrared spectroscopy (fNIRS) is an emerging non-invasive brain imaging technique and measures brain activities by means of near-infrared light of 650-950 nm wavelengths. The cortical hemodynamic response (HR) differs in attributes at different brain regions and on repetition of trials, even if the experimental paradigm is kept exactly the same. Therefore, an HR model that can estimate such variations in the response is the objective of this research. The canonical hemodynamic response function (cHRF) is modeled by two Gamma functions with six unknown parameters (four of them to model the shape and other two to scale and baseline respectively). The HRF model is supposed to be a linear combination of HRF, baseline, and physiological noises (amplitudes and frequencies of physiological noises are supposed to be unknown). An objective function is developed as a square of the residuals with constraints on 12 free parameters. The formulated problem is solved by using an iterative optimization algorithm to estimate the unknown parameters in the model. Inter-subject variations in HRF and physiological noises have been estimated for better cortical functional maps. The accuracy of the algorithm has been verified using 10 real and 15 simulated data sets. Ten healthy subjects participated in the experiment and their HRF for finger-tapping tasks have been estimated and analyzed. The statistical significance of the estimated activity strength parameters has been verified by employing statistical analysis (i.e., t-value > t critical and p-value < 0.05).

  1. Rapid determination of sugar level in snack products using infrared spectroscopy.

    Science.gov (United States)

    Wang, Ting; Rodriguez-Saona, Luis E

    2012-08-01

    Real-time spectroscopic methods can provide a valuable window into food manufacturing to permit optimization of production rate, quality and safety. There is a need for cutting edge sensor technology directed at improving efficiency, throughput and reliability of critical processes. The aim of the research was to evaluate the feasibility of infrared systems combined with chemometric analysis to develop rapid methods for determination of sugars in cereal products. Samples were ground and spectra were collected using a mid-infrared (MIR) spectrometer equipped with a triple-bounce ZnSe MIRacle attenuated total reflectance accessory or Fourier transform near infrared (NIR) system equipped with a diffuse reflection-integrating sphere. Sugar contents were determined using a reference HPLC method. Partial least squares regression (PLSR) was used to create cross-validated calibration models. The predictability of the models was evaluated on an independent set of samples and compared with reference techniques. MIR and NIR spectra showed characteristic absorption bands for sugars, and generated excellent PLSR models (sucrose: SEP 0.96). Multivariate models accurately and precisely predicted sugar level in snacks allowing for rapid analysis. This simple technique allows for reliable prediction of quality parameters, and automation enabling food manufacturers for early corrective actions that will ultimately save time and money while establishing a uniform quality. The U.S. snack food industry generates billions of dollars in revenue each year and vibrational spectroscopic methods combined with pattern recognition analysis could permit optimization of production rate, quality, and safety of many food products. This research showed that infrared spectroscopy is a powerful technique for near real-time (approximately 1 min) assessment of sugar content in various cereal products. © 2012 Institute of Food Technologists®

  2. Application of infrared spectroscopy in the identification of Ewing sarcoma: A preliminary report

    Science.gov (United States)

    Chaber, Radosław; Łach, Kornelia; Szmuc, Kamil; Michalak, Elżbieta; Raciborska, Anna; Mazur, Damian; Machaczka, Maciej; Cebulski, Józef

    2017-06-01

    Fourier transform infrared (FTIR) spectroscopy is a highly sensitive, non-invasive analytical technique that can provide information about molecular changes in a biological sample. FTIR spectrum is a sum of the frequencies of many biomolecules which reveals a biochemical fingerprint for mineral identification, and can be analyzed for information about the mineral structure of malignant cells. This gives us the potential to differentiate tumor cells from normal cells in the early stage of relapse, before the tumor cells would be detectable in light microscopy. Ewing sarcoma (ES) is the second most common malignant bone tumor found in children and adolescents. ES affects annually almost 3 persons/1,000,000 mostly children and young adults under 20 years of age annually. ES originates from primitive, low-differentiated neuroectodermal cells. The current standard of therapy for ES is the surgical resection of the primary tumor and metastasis in combination with the chemo- and radiotherapy. The aim of this study was to compare the spectra of ES bone samples and the spectra of normal bone tissues, analyzed before and after induction chemotherapy, by means of FTIR spectroscopy. Six patients with ES affecting bones aged 5.5-16.5 years (median age 11.2 years), who were treated between 2011 and 2015, were included to the study. In all analyzed patients, the diagnosis of ES and the assessment of response to the chemotherapy were performed according to the Euro-EWING-2008 protocol. The Fourier transform infrared spectroscope (FT-IR; Vertex 70v from Bruker) was used in this study. Tissue specimens were applied to the attenuated total reflection (ATR) in the infrared (IR) radiation from the mid-infrared range using a single-reflection snap ATR crystal diamond. In the FTIR spectra we observed a shift in the wave number of the phosphate ion (from 3 to 26 [cm-1]) associated with the presence of tumor tissue. After chemotherapy, a change of the FTIR spectrum was associated with the

  3. Identification of natural red and purple dyes on textiles by Fiber-optics Reflectance Spectroscopy.

    Science.gov (United States)

    Maynez-Rojas, M A; Casanova-González, E; Ruvalcaba-Sil, J L

    2017-05-05

    Understanding dye chemistry and dye processes is an important issue for studies of cultural heritage collections and science conservation. Fiber Optics Reflectance Spectroscopy (FORS) is a powerful technique, which allows preliminary dye identification, causing no damage or mechanical stress on the artworks subjected to analysis. Some information related to specific light scattering and absorption can be obtained in the UV-visible and infrared range (300-1400nm) and it is possible to discriminate the kind of support fiber in the near infrared region (1000-2500nm). The main spectral features of natural dye fibers samples, such as reflection maxima, inflection points and reflection minima, can be used in the differentiation of various red natural dyes. In this work, a set of dyed references were manufactured following Mexican recipes with red dyes (cochineal and brazilwood) in order to determine the characteristic FORS spectral features of fresh and aged dyed fibers for their identification in historical pieces. Based on these results, twenty-nine indigenous textiles belonging to the National Commission for the Development of Indigenous People of Mexico were studied. Cochineal and brazilwood were successfully identified by FORS in several pieces, as well as the mixture of cochineal and indigo for purple color. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Assessing human skin with diffuse reflectance spectroscopy and colorimetry

    Science.gov (United States)

    Seo, InSeok; Liu, Yang; Bargo, Paulo R.; Kollias, Nikiforos

    2012-02-01

    Colorimetry has been used as an objective measure of perceived skin color by human eye to document and score physiological responses of the skin from external insults. CIE color space values (L*, a* and b*) are the most commonly used parameters to correlate visually perceived color attributes such as L* for pigment, a* for erythema, and b* for sallowness of the skin. In this study, we investigated the relation of Lab color scale to the amount of major skin chromophores (oxy-, deoxyhemoglobin and melanin) calculated from diffuse reflectance spectroscopy. Thirty two healthy human subjects with ages from 20 to 70 years old, skin types I-VI, were recruited for the study. DRS and colorimetry measurements were taken from the left and right cheeks, and on the right upper inner arm. The melanin content calculated from 630-700 nm range of DRS measurements was shown to correlate with the lightness of skin (L*) for most skin types. For subjects with medium-to-light complexion, melanin measured at the blue part spectrum and hemoglobin interfered on the relation of lightness of the skin color to the melanin content. The sallowness of the skin that is quantified by the melanin contribution at the blue part spectrum of DRS was found to be related to b* scale. This study demonstrates the importance of documenting skin color by assessing individual skin chromophores with diffuse reflectance spectroscopy, in comparison to colorimetry assessment.

  5. Development of an ultra-compact mid-infrared attenuated total reflectance spectrophotometer

    Science.gov (United States)

    Kim, Dong Soo; Lee, Tae-Ro; Yoon, Gilwon

    2014-07-01

    Mid-infrared spectroscopy has been an important tool widely used for qualitative analysis in various fields. However, portable or personal use is size and cost prohibitive for either Fourier transform infrared or attenuated total reflectance (ATR) spectrophotometers. In this study, we developed an ultra-compact ATR spectrophotometer whose frequency band was 5.5-11.0 μm. We used miniature components, such as a light source fabricated by semiconductor technology, a linear variable filter, and a pyro-electric array detector. There were no moving parts. Optimal design based on two light sources, a zippered configuration of the array detector and ATR optics could produce absorption spectra that might be used for qualitative analysis. A microprocessor synchronized the pulsed light sources and detector, and all the signals were processed digitally. The size was 13.5×8.5×3.5 cm3 and the weight was 300 grams. Due to its low cost, our spectrophotometer can replace many online monitoring devices. Another application could be for a u-healthcare system installed in the bathroom or attached to a smartphone for monitoring substances in body fluids.

  6. Diffuse Reflectance Infrared Fourier Transform Study of NOx Adsorption on CGO10 Impregnated with K2O or BaO

    DEFF Research Database (Denmark)

    Traulsen, Marie Lund; Härelind Ingelsten, H.; Kammer Hansen, Kent

    2012-01-01

    In the present work Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectroscopy is applied to study the adsorption of NOx at 300-500 °C in different atmospheres on gadolinium doped ceria (CGO), an important material in electrodes investigated for electrochemical NOx removal. Furthermore...

  7. Infrared spectroscopy of one-dimensional metallic nanostructures on silicon vicinal surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Hoang, Chung Vu

    2010-06-23

    Vicinal silicon(111) surfaces are used as templates for the growth of lead nanowires as well as gold and indium atom chains. The morphology of the Au atom chains was studied by use of Scanning Tunneling Microscopy (STM) and Reflection High Energy Electron Diffraction (RHEED). The In chains were investigated by infrared spectroscopy with the electrical field component of the IR light polarized either parallel or perpendicular to the wires. It is shown that at room temperature, In atom-chains display a plasmonic absorption feature along the chain but not in the perpendicular direction. Furthermore, upon cooling down to liquid nitrogen temperature, a metal to insulator transition is observed. A structural distortion is also confirmed by RHEED. As for the result of Pb nanowires, by means of infrared spectroscopy, it is now possible to control the average length of parallel nanowire arrays by monitoring four experimental parameters that influence on the nucleation density; namely: Pb coverage, evaporation rate, substrate temperature and the surface itself. The system shows an enhancement of the absorption at the antenna frequency in the low temperature regime. This scenario is assigned to the reduction of electron-phonon scattering due to low temperature. (orig.)

  8. Infrared spectroscopy of one-dimensional metallic nanostructures on silicon vicinal surfaces

    International Nuclear Information System (INIS)

    Hoang, Chung Vu

    2010-01-01

    Vicinal silicon(111) surfaces are used as templates for the growth of lead nanowires as well as gold and indium atom chains. The morphology of the Au atom chains was studied by use of Scanning Tunneling Microscopy (STM) and Reflection High Energy Electron Diffraction (RHEED). The In chains were investigated by infrared spectroscopy with the electrical field component of the IR light polarized either parallel or perpendicular to the wires. It is shown that at room temperature, In atom-chains display a plasmonic absorption feature along the chain but not in the perpendicular direction. Furthermore, upon cooling down to liquid nitrogen temperature, a metal to insulator transition is observed. A structural distortion is also confirmed by RHEED. As for the result of Pb nanowires, by means of infrared spectroscopy, it is now possible to control the average length of parallel nanowire arrays by monitoring four experimental parameters that influence on the nucleation density; namely: Pb coverage, evaporation rate, substrate temperature and the surface itself. The system shows an enhancement of the absorption at the antenna frequency in the low temperature regime. This scenario is assigned to the reduction of electron-phonon scattering due to low temperature. (orig.)

  9. Rapidly Simultaneous Determination of Six Effective Components in Cistanche tubulosa by Near Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Xinhong Wang

    2017-05-01

    Full Text Available Quantitative determination of multiple effective components in a given plant usually requires a very large amount of authentic natural products. In this study, we proposed a rapid and non-destructive method for the simultaneous determination of echinacoside, verbascoside, mannitol, sucrose, glucose and fructose in Cistanche tubulosa by near infrared spectroscopy (NIRS. Near infrared diffuse reflectance spectroscopy (DRS and high performance liquid chromatography (HPLC were conducted on 116 batches of C. tubulosa samples. The DRS data were processed using standard normal variety (SNV and multiplicative scatter correction (MSC methods. Partial least squares regression (PLSR was utilized to build calibration models for components-of-interest in C. tubulosa. All models were then assessed by calculating the root mean square error of calibration (RMSEC, correlation coefficient of calibration (r. The r values of all six calibration models were determined to be greater than 0.94, suggesting each model is reliable. Therefore, the quantitative NIR models reported in this study can be qualified to accurately quantify the contents of six medicinal components in C. tubulosa.

  10. Methodological effects in Fourier transform infrared (FTIR) spectroscopy: Implications for structural analyses of biomacromolecular samples

    Science.gov (United States)

    Kamnev, Alexander A.; Tugarova, Anna V.; Dyatlova, Yulia A.; Tarantilis, Petros A.; Grigoryeva, Olga P.; Fainleib, Alexander M.; De Luca, Stefania

    2018-03-01

    A set of experimental data obtained by Fourier transform infrared (FTIR) spectroscopy (involving the use of samples ground and pressed with KBr, i.e. in a polar halide matrix) and by matrix-free transmission FTIR or diffuse reflectance infrared Fourier transform (DRIFT) spectroscopic methodologies (involving measurements of thin films or pure powdered samples, respectively) were compared for several different biomacromolecular substances. The samples under study included poly-3-hydroxybutyrate (PHB) isolated from cell biomass of the rhizobacterium Azospirillum brasilense; dry PHB-containing A. brasilense biomass; pectin (natural carboxylated heteropolysaccharide of plant origin; obtained from apple peel) as well as its chemically modified derivatives obtained by partial esterification of its galacturonide-chain hydroxyl moieties with palmitic, oleic and linoleic acids. Significant shifts of some FTIR vibrational bands related to polar functional groups of all the biomacromolecules under study, induced by the halide matrix used for preparing the samples for spectroscopic measurements, were shown and discussed. A polar halide matrix used for preparing samples for FTIR measurements was shown to be likely to affect band positions not only per se, by affecting band energies or via ion exchange (e.g., with carboxylate moieties), but also by inducing crystallisation of metastable amorphous biopolymers (e.g., PHB of microbial origin). The results obtained have important implications for correct structural analyses of polar, H-bonded and/or amphiphilic biomacromolecular systems using different methodologies of FTIR spectroscopy.

  11. Infrared fiber optic evanescent wave spectroscopy: applications in biology and medicine

    Science.gov (United States)

    Afanasyeva, Natalia I.; Bruch, Reinhard F.; Katzir, Abraham

    1999-04-01

    A new powerful and highly sensitive technique for non-invasive biomedical diagnostics in vivo has been developed using Infrared Fiberoptic Evanescent Wave Fourier Transform Spectroscopy (FEW-FTIR). This compact and portable method allows to detect functional chemical groups and bonds via vibrational spectroscopy directly from surfaces including living tissue. Such differences and similarities in molecular structure of tissue and materials can be evaluated online. Operating in the attenuated total reflection (ATR) regime in the middle-infrared (MIR) range, the FEW-FTIR technique provides direct contact between the fiber probe and tissue for non-destructive, non-invasive, fast and remote (few meters) diagnostics and quality control of materials. This method utilizes highly flexible and extremely low loss unclad fibers, for example silver halide fibers. Applications of this method include investigations of normal skin, precancerous and cancerous conditions, monitoring of the process of aging, allergic reactions and radiation damage to the skin. This setup is suitable as well for the detection of the influence of environmental factors (sun, water, pollution, and weather) on skin surfaces. The FEW-FTIR technique is very promising also for fast histological examinations in vitro. In this review, we present recent investigations of skin, breast, lung, stomach, kidney tissues in vivo and ex vivo (during surgery) to define the areas of tumor localization. The main advantages of the FEW-FTIR technique for biomedical, clinical, and environmental applications are discussed.

  12. Discriminating nicotine and non-nicotine containing e-liquids using infrared spectroscopy.

    Science.gov (United States)

    Deconinck, E; Bothy, J L; Barhdadi, S; Courselle, P

    2016-02-20

    In a few countries, including Belgium, nicotine-containing e-cigarettes and e-liquids are considered medicines, and therefore cannot freely be sold, but should be distributed in a pharmacy. The fact that in the neighbouring countries these products are freely available, poses a problem for custom personnel, the more the nicotine content of the products is not always labelled, especially when they are bought through internet. Therefore there is a need for easy-to-use equipment and methods to perform a first on site screening of intercepted samples, both for border control as to check label compliance of the sample. The use of attenuated total reflectance-infrared spectroscopy (ATR-IR) and near infrared spectroscopy (NIR), combined with chemometrics was evaluated for the discrimination between nicotine containing and non-nicotine containing samples. It could be concluded that both ATR-IR and NIR could be used for the discrimination when combined with the appropriate chemometric techniques. The presented techniques do not need sample preparation and result in models with a minimum of false negative samples. If a large enough training set can be established the interpretation can be fully automated, making the presented approach suitable for on-site screening of e-liquid samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. State of dissolved water in triglycerides as determined by Fourier transform infrared and near infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kurashige, J. (Ajinomoto Co. Inc., Tokyo (Japan)); Takaoka, K.; Takasago, M.; Taru, Y.; Kobayashi, K. (Musashi Institute of Technology, Tokyo (Japan))

    1991-07-20

    The states of dissolved water in triglycerides (TG) such as tristearin, triolein, trilinolein and trilinolenin were analyzed by Fourier transform infrared (FT-IR) and near infrared (FT-NIR) spectroscopy, and compared with those of water itself. In the case of water, its states were considered to be mainly polymer clusters larger than dimer ones at 20{degree}C, and mostly monomer or dimer clusters at 120{degree}C. In TG, the states varied widely from monomer to polymer clusters at 20{degree}C. The distribution ratios of the water clusters observed in TG depended on the kinds of fatty acids of TG, and the water state was noted to change due to the interaction between unsaturated bonds and dissolved water. Although the states of dissolved water in trilinolein were similar to those of original water at 20{degree}C, the ratio of monomer water decreased and polymer clusters bigger than those in original water increased with an increase in number of unsaturated bonds of TG. 9 refs., 6 figs., 3 tabs.

  14. Characterizing process effects on pharmaceutical solid forms using near-infrared spectroscopy and infrared imaging.

    Science.gov (United States)

    Roggo, Y; Jent, N; Edmond, A; Chalus, P; Ulmschneider, M

    2005-09-01

    Near-infrared spectroscopy (NIRS) has become a widely used analytical technique in the pharmaceutical industry, serving for example to determine the active substance or water content of tablets. Its great advantage lies in the minimal sample preparation required and speed of measurement. In a study designed to detect the effects of process on tablet dissolution, we describe the application of NIRS to the detection and identification of changes in uncoated and coated tablets in response to pilot-scale changes in process parameters during melt granulation, compression, and coating. Beginning with a qualitative comparison between pharmaceutical batches, we show that NIRS and principal component analysis can separate batches produced with different melt granulation parameters and differentiate between cores compressed with different compaction forces. Complementary infrared imaging can also explain the difference in dissolution properties between samples produced with different melt granulation parameters. NIRS is sensitive to changes in coating formulation, the quality of a coating excipient (hydroxypropyl methylcellulose), and coating time. In a concluding quantitative analysis, we demonstrate the feasibility of NIRS in a manufacturing context for predicting coating time and detecting production cores failing to meet dissolution test specifications.

  15. Autofluorescence and diffuse reflectance patterns in cervical spectroscopy

    Science.gov (United States)

    Marin, Nena Maribel

    Fluorescence and diffuse reflectance spectroscopy are two new optical technologies, which have shown promise to aid in the real time, non-invasive identification of cancers and precancers. Spectral patterns carry a fingerprint of scattering, absorption and fluorescence properties in tissue. Scattering, absorption and fluorescence in tissue are directly affected by biological features that are diagnostically significant, such as nuclear size, micro-vessel density, volume fraction of collagen fibers, tissue oxygenation and cell metabolism. Thus, analysis of spectral patterns can unlock a wealth of information directly related with the onset and progression of disease. Data from a Phase II clinical trial to assess the technical efficacy of fluorescence and diffuse reflectance spectroscopy acquired from 850 women at three clinical locations with two research grade optical devices is calibrated and analyzed. Tools to process and standardize spectra so that data from multiple spectrometers can be combined and analyzed are presented. Methodologies for calibration and quality assurance of optical systems are established to simplify design issues and ensure validity of data for future clinical trials. Empirically based algorithms, using multivariate statistical approaches are applied to spectra and evaluated as a clinical diagnostic tool. Physically based algorithms, using mathematical models of light propagation in tissue are presented. The presented mathematical model combines a diffusion theory in P3 approximation reflectance model and a 2-layer fluorescence model using exponential attenuation and diffusion theory. The resulting adjoint fluorescence and reflectance model extracts twelve optical properties characterizing fluorescence efficiency of cervical epithelium and stroma fluorophores, stromal hemoglobin and collagen absorption, oxygen saturation, and stromal scattering strength and shape. Validations with Monte Carlo simulations show that adjoint model extracted

  16. Far-infrared phonon spectroscopy of Pb1-xMn xTe layers grown by molecular beam epitaxy

    International Nuclear Information System (INIS)

    Romcevic, N.; Nadolny, A.J.; Romcevic, M.; Story, T.; Taliashvili, B.; Milutinovic, A.; Trajic, J.; Lusakowska, E.; Vasiljevic-Radovic, D.; Domukhovski, V.; Osinniy, V.; Hadzic, B.; Dziawa, P.

    2007-01-01

    In this paper we used far-infrared spectroscopy, reflection high energy electron diffraction (RHEED), X-ray diffraction and atomic force microscopy (AFM) to investigate structural and optical properties of Pb 1-x Mn x Te layers grown by molecular beam epitaxy (MBE). A numerical model for calculating the reflectivity coefficient for complex systems which include films, buffer layer and substrate has been applied. The infrared reflectivity spectra consist of Pb 1-x Mn x Te phonons, which exhibit intermediate one-two mode behavior, and MnTe phonons. A good agreement between calculated and experimental spectra is achieved. We registered the local distribution of Mn impurities depending on substrate type. For films growth on BaF 2 substrate we registered the orthorhombic local structure of MnTe clusters, while in the case of KCl substrate this structure is cubic. The Pb 1-x Mn x Te long wavelength optical phonons were described by the modified Genzel's model

  17. Thyroid lesions diagnosis by Fourier transformed infrared absorption spectroscopy (FTIR)

    International Nuclear Information System (INIS)

    Albero, Felipe Guimaraes

    2009-01-01

    Thyroid nodules are a common disorder, with 4-7% of incidence in the Brazilian population. Although the fine needle aspiration (FNA) is an accurate method for thyroid tumors diagnosis, the discrimination between benign and malignant neoplasm is currently not possible in some cases with high incidence of false negative diagnosis, leading to a surgical intervention due to the risk of carcinomas. The aim of this study was to verify if the Fourier Transform infrared spectroscopy (FTIR) can contribute to the diagnosis of thyroid carcinomas and goiters, using samples of tissue and aspirates. Samples of FNA, homogenates and tissues of thyroid nodules with histopathological diagnosis were obtained and prepared for FTIR spectroscopy analysis. The FNA and homogenates samples were measured by μ-FTIR (between 950 . 1750 cm -1 ), at a nominal resolution of 4 cm -1 and 120 scans). Tissue samples were analyzed directly by ATR-FTIR technique, at a resolution 2 cm -1 , with 60 scans in the same region. All spectra were corrected by the baseline and normalized by amides area (1550-1640 cm -1 ) in order to minimize variations of sample homogeneity. Then, spectra were converted into second derivatives using the Savitzk-Golay algorithm with a 13 points window. The Ward's minimum variance algorithm and Euclidean distances among the points were used for cluster analysis. Some FNA samples showed complex spectral pattern. All samples showed some cell pellets and large amount of hormone, represented by the bands of 1545 and 1655 cm -1 . Bands in 1409, 1412, 1414, 1578 and 1579 cm -1 were also found, indicating possible presence of sugar, DNA, citric acid or metabolic products. In this study, it was obtained an excellent separation between goiter and malign lesion for the samples of tissues, with 100% of specificity in specific cluster and 67% sensibility and 50 of specificity. In homogenate and FNA samples this sensibility and specificity were lower, because among these samples, it were

  18. The Use of Infrared Spectroscopy to Determine the Quality of Carbonate-Rich Diatomite Ores

    Directory of Open Access Journals (Sweden)

    Adriana Guatame-Garcia

    2018-03-01

    Full Text Available Diatomite, a rock formed by the accumulation of opaline diatom frustules, is a preferred raw material for the manufacturing of filters. Its uniqueness relies on the high porosity and inertness of the frustules. The presence of carbonates in some diatomite ores hinders these properties. The purpose of this study was to identify the type of carbonates and their association with the ore in a diatomite deposit, and to assess the suitability of determining the quality of the ore using techniques with potential for in-pit implementation. For this, run-of-mine samples were analysed using environmental scanning electron microscopy (ESEM and infrared spectroscopy. The ESEM images showed that carbonate is present as cement and laminae. The infrared data revealed that the carbonate minerals correspond to aragonite and calcite, and that their occurrence is linked to the total amount of carbonate in the sample. By using a portable spectral instrument that uses diffuse reflectance, it was possible to classify the spectra of the ore samples based on the carbonate content. These results indicate that infrared technology could be used on-site for determining the quality of the ore, thus providing relevant information to assist the optimisation of mining and beneficiation activities.

  19. Rapid assessment of selected free amino acids during Edam cheese ripening by near infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Jiří Mlček

    2013-01-01

    Full Text Available The study focuses on rapid determination of free amino acids produced during the ripening of cheese, by using near infrared spectroscopy. Analyses of 96 samples of Edam cheese (30% and 45% of fat in dry matter were performed at monthly intervals up to the ripening age of 6 months. In total, 19 amino acids were analysed with infrared spectrometer using two different methods, either in the regime of reflectance in the integrating sphere of the apparatus or using a fibre optic apparatus with the fibre optic probe. Reference data based on high-performance liquid chromatography were used for calibration of the spectrophotometer. Calibration models were developed using a partial least square algorithm and tested by means of cross-validation. When measured with the integrating sphere and with the probe, the values of correlation coefficients ranged from 0.835 to 0.993 and from 0.739 to 0.995, respectively. Paired t-test did not show significant differences between the reference and predicted values (P < 0.05. The results of this new calibration method showed the possibility of near infrared technology for fast determination of free amino acids, which occur during the ripening of Edam cheese. The content of free amino acids allow us to prepare Edam cheese quickly and efficiently for sale or to prepare the material for processed cheese.

  20. Noninvasive measurement of postocclusive parameters in human forearm blood by near infrared spectroscopy

    Science.gov (United States)

    Rao, K. Prahlad; Radhakrishnan, S.; Reddy, M. Ramasubba

    2005-04-01

    Near infrared (NIR) light in the wavelength range from 700 to 900 nm can pass through skin, bone and other tissues relatively easily. As a result, NIR techniques allow a noninvasive assessment of hemoglobin saturation for a wide range of applications, such as in the study of muscle metabolism, the diagnosis of vascular disorders, brain imaging, and breast cancer detection. Near infrared Spectroscopy (NIRS) is an effective tool to measure the hemoglobin concentration in the tissues, which can discriminate optically the oxy- and deoxy- hemoglobin species because of their different near-infrared absorption spectra. We have developed an NIRS probe consisting of a laser diode of 830 nm wavelength and a PIN photodiode in reflectance mode. We have selected a set of healthy volunteers (mean age 30, range 26-40 years) for the study. The probe is placed on forearm of each subject and the backscattered light intensity is measured by occluding the blood flow at 210, 110 and 85 mmHg pressures. Recovery time, peak time and time after 50% release of the cuff pressure are determined from the optical densities during the post occlusive state of forearm. These parameters are useful for determining the transient increase in blood flow after the release of blood occlusion. Clinically, the functional aspects of blood flow in the limbs could be evaluated noninvasively by NIRS.

  1. Near infrared spectroscopy in the study of polymorphic transformations

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, Marcel [Department of Chemistry, Analytical Chemistry Unity, Faculty of Sciences, Autonomous University of Barcelona, E-08193 Bellaterra, Barcelona (Spain)]. E-mail: marcel.blanco@uab.es; Alcala, Manel [Department of Chemistry, Analytical Chemistry Unity, Faculty of Sciences, Autonomous University of Barcelona, E-08193 Bellaterra, Barcelona (Spain); Gonzalez, Josep M. [Laboratorios Menarini S.A., c/. Alfons XII, 587, E-08918 Badalona, Barcelona (Spain); Torras, Ester [Laboratorios Menarini S.A., c/. Alfons XII, 587, E-08918 Badalona, Barcelona (Spain)

    2006-05-17

    The potential of near infrared (NIR) spectroscopy for the characterization of polymorphs in the active principle of a commercial formulation prior to and after the manufacturing process was assessed. Polymorphism in active principles is extremely significant to the pharmaceutical industry. Polymorphic changes during the production of commercial pharmaceutical formulations can alter some properties of the resulting end-products. Multivariate curve resolution-alternating least squares (MCR-ALS) methodology was used to obtain the 'pure' NIR spectrum for the active principle without the need to pretreat samples. This methodology exposed the polymorphic transformation of Dexketoprofen Trometamol (DKP) in both laboratory and production samples obtained by wet granulation. No polymorphic transformation, however, was observed in samples obtained by direct compaction. These results were confirmed using by X-ray powder diffractometry (XRD) and differential scanning calorimetry (DSC) measurements. Pure crystalline polymorphs of DKP were available in the laboratory but amorphous form was not, nevertheless the developed methodology allows the identification of amorphous and crystal forms in spite of the lack of pure DKP.

  2. The application of near infrared spectroscopy in nutritional intervention studies

    Directory of Open Access Journals (Sweden)

    Philippa A Jackson

    2013-08-01

    Full Text Available Functional near infrared spectroscopy (NIRS is a non-invasive optical imaging technique used to monitor cerebral blood flow (CBF and by proxy neuronal activation. The use of NIRS in nutritional intervention studies is a relatively novel application of this technique, with only a small, but growing, number of trials published to date. These trials—in which the effects on CBF following administration of dietary components such as caffeine, polyphenols and omega-3 polyunsaturated fatty acids are assessed—have successfully demonstrated NIRS as a sensitive measure of change in haemodynamic response during cognitive tasks in both acute and chronic treatment intervention paradigms. The existent research in this area has been limited by the constraints of the technique itself however advancements in the measurement technology, paired with studies endeavouring increased sophistication in number and locations of channels over the head should render the use of NIRS in nutritional interventions particularly valuable in advancing our understanding of the effects of nutrients and dietary components on the brain.

  3. Quantification of atmospheric formaldehyde by infrared absorption spectroscopy

    Science.gov (United States)

    Hoffnagle, John; Fleck, Derek; Rella, Chris; Kim-Hak, David

    2017-04-01

    Formaldehyde is a toxic, carcinogenic compound that can contaminate ambient air as a result of combustion or outgassing of commercial products such as adhesives used to fabricate plywood and to affix indoor carpeting. Like many small molecules, formaldehyde has an infrared absorption spectrum exhibiting bands of ro-vibrational transitions that are well resolved at low pressure and therefore well suited for optical analysis of formaldehyde concentration. We describe progress in applying cavity ring-down spectroscopy of the 2v5 band (the first overtone of the asymmetric C-H stretch, origin at 1770 nm) to the quantitative analysis of formaldehyde concentration in ambient air. Preliminary results suggest that a sensitivity of 1-2 ppb in a measurement interval of a few seconds, and 0.1-0.2 ppb in a few minutes, should be achievable with a compact, robust, and field-deployable instrument. Finally, we note that recent satellites monitoring snapshots of formaldehyde columns give insights into global formaldehyde production, migration and lifetime. The ability to monitor formaldehyde with a small and portable analyzer has the potential to aid in validation of these snapshots and to provide complementary data to show vertical dispersions with high spatial accuracy.

  4. Portable Infrared Laser Spectroscopy for On-site Mycotoxin Analysis

    Science.gov (United States)

    Sieger, Markus; Kos, Gregor; Sulyok, Michael; Godejohann, Matthias; Krska, Rudolf; Mizaikoff, Boris

    2017-03-01

    Mycotoxins are toxic secondary metabolites of fungi that spoil food, and severely impact human health (e.g., causing cancer). Therefore, the rapid determination of mycotoxin contamination including deoxynivalenol and aflatoxin B1 in food and feed samples is of prime interest for commodity importers and processors. While chromatography-based techniques are well established in laboratory environments, only very few (i.e., mostly immunochemical) techniques exist enabling direct on-site analysis for traders and manufacturers. In this study, we present MYCOSPEC - an innovative approach for spectroscopic mycotoxin contamination analysis at EU regulatory limits for the first time utilizing mid-infrared tunable quantum cascade laser (QCL) spectroscopy. This analysis technique facilitates on-site mycotoxin analysis by combining QCL technology with GaAs/AlGaAs thin-film waveguides. Multivariate data mining strategies (i.e., principal component analysis) enabled the classification of deoxynivalenol-contaminated maize and wheat samples, and of aflatoxin B1 affected peanuts at EU regulatory limits of 1250 μg kg-1 and 8 μg kg-1, respectively.

  5. Near Infrared Spectroscopy during pediatric cardiac surgery: errors and pitfalls.

    Science.gov (United States)

    Durandy, Y; Rubatti, M; Couturier, R

    2011-09-01

    As a result of improvements in early outcomes, long-term neurologicalal outcomes are becoming a major issue in pediatric cardiac surgery. The mechanisms of brain injury are numerous, but a vast majority of injuries are impervious to therapy and only a few are modifiable. The quality of perfusion during cardiac surgery is a modifiable factor and cerebral monitoring during bypass is the way to assess the quality of intra-operative cerebral perfusion. Near infrared spectroscopy (NIRS), as a diagnostic tool, has gained in popularity within the perfusion community. However, NIRS is becoming the standard of care before its scientific validation. This manuscript relates four clinical cases, demonstrating the limitations of NIRS monitoring during pediatric cardiac surgery as well as uncertainties about the interpretation of the recorded values. The clinical relevance of cerebral oxymetry is needed before the use of NIRS as a decision making tool. Multimodal brain monitoring with NIRS, trans-cranial Doppler and electroencephalogram are currently under way in several pediatric centers. The benefit of this time-consuming and expensive monitoring system has yet to be demonstrated.

  6. Near infrared spectroscopy based brain-computer interface

    Science.gov (United States)

    Ranganatha, Sitaram; Hoshi, Yoko; Guan, Cuntai

    2005-04-01

    A brain-computer interface (BCI) provides users with an alternative output channel other than the normal output path of the brain. BCI is being given much attention recently as an alternate mode of communication and control for the disabled, such as patients suffering from Amyotrophic Lateral Sclerosis (ALS) or "locked-in". BCI may also find applications in military, education and entertainment. Most of the existing BCI systems which rely on the brain's electrical activity use scalp EEG signals. The scalp EEG is an inherently noisy and non-linear signal. The signal is detrimentally affected by various artifacts such as the EOG, EMG, ECG and so forth. EEG is cumbersome to use in practice, because of the need for applying conductive gel, and the need for the subject to be immobile. There is an urgent need for a more accessible interface that uses a more direct measure of cognitive function to control an output device. The optical response of Near Infrared Spectroscopy (NIRS) denoting brain activation can be used as an alternative to electrical signals, with the intention of developing a more practical and user-friendly BCI. In this paper, a new method of brain-computer interface (BCI) based on NIRS is proposed. Preliminary results of our experiments towards developing this system are reported.

  7. Human Milk Analysis Using Mid-Infrared Spectroscopy.

    Science.gov (United States)

    Groh-Wargo, Sharon; Valentic, Jennifer; Khaira, Sharmeel; Super, Dennis M; Collin, Marc

    2016-04-01

    The composition of human milk is known to vary with length of gestation, stage of lactation, and other factors. Human milk contains all nutrients required for infant health but requires fortification to meet the needs of low-birth-weight infants. Without a known nutrient profile of the mother's milk or donor milk fed to a baby, the composition of the fortified product is only an estimate. Human milk analysis has the potential to improve the nutrition care of high-risk newborns by increasing the information about human milk composition. Equipment to analyze human milk is available, and the technology is rapidly evolving. This pilot study compares mid-infrared (MIR) spectroscopy to reference laboratory milk analysis. After obtaining informed consent, we collected human milk samples from mothers of infants weighing milk obtained by MIR vs reference laboratory analysis. MIR analysis appears to provide an accurate assessment of macronutrient content in expressed human milk from mothers of preterm infants. The small sample size of this study limits confidence in the results. Measurement of lactose is confounded by the presence of oligosaccharides. Human milk analysis is a potentially useful tool for establishing an individualized fortification plan. © 2015 American Society for Parenteral and Enteral Nutrition.

  8. Fully Automated Lipid Pool Detection Using Near Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Elżbieta Pociask

    2016-01-01

    Full Text Available Background. Detecting and identifying vulnerable plaque, which is prone to rupture, is still a challenge for cardiologist. Such lipid core-containing plaque is still not identifiable by everyday angiography, thus triggering the need to develop a new tool where NIRS-IVUS can visualize plaque characterization in terms of its chemical and morphologic characteristic. The new tool can lead to the development of new methods of interpreting the newly obtained data. In this study, the algorithm to fully automated lipid pool detection on NIRS images is proposed. Method. Designed algorithm is divided into four stages: preprocessing (image enhancement, segmentation of artifacts, detection of lipid areas, and calculation of Lipid Core Burden Index. Results. A total of 31 NIRS chemograms were analyzed by two methods. The metrics, total LCBI, maximal LCBI in 4 mm blocks, and maximal LCBI in 2 mm blocks, were calculated to compare presented algorithm with commercial available system. Both intraclass correlation (ICC and Bland-Altman plots showed good agreement and correlation between used methods. Conclusions. Proposed algorithm is fully automated lipid pool detection on near infrared spectroscopy images. It is a tool developed for offline data analysis, which could be easily augmented for newer functions and projects.

  9. Polarization contrast linear spectroscopies for cubic semiconductors under stress: macro- and micro-reflectance difference spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Lastras-Martinez, L.F.; Balderas-Navarro, R.E.; Castro-Garcia, R.; Herrera-Jasso, R.; Lastras-Martinez, A. [Instituto de Investigacion en Comunicacion Optica, Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi, S.L.P. (Mexico); Chavira-Rodriguez, M. [Departamento de Fisico Matematicas, Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi, S.L.P. (Mexico)

    2011-01-15

    The technique to measure optical anisotropies (OA) in cubic semiconductors is termed either reflectance difference spectroscopy (RDS) or reflectance anisotropy spectroscopy (RAS). In this paper we report on the application of RDS/RAS to a number of cubic semiconductors. We discuss RD spectra of GaAs, Si, CdTe, GaP, InP and GaSb (001) surfaces, induced by an uniaxial stress applied along [110] crystal directions. We show that all RD spectra can be explained in terms of a phenomenological model based on a perturbative Hamiltonian. We further report on measurements of spatial-resolved RDS measurements of GaAs employing a newly developed micro-RD spectrometer with a spatial resolution of 5 {mu}m. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Infrared reflectance of GaN films grown on Si(001) substrates

    International Nuclear Information System (INIS)

    Zhang, Xiong; Hou, Yong-Tian; Feng, Zhe-Chuan; Chen, Jin-Li

    2001-01-01

    GaN thin films on Si(001) substrates are studied by infrared reflectance (IRR) spectroscopy at room temperature (RT). Variations in the IRR spectral line shape with the microstructure of GaN/Si(011) film are quantitatively explained in terms of a three-component effective medium model. In this model, the nominally undoped GaN film is considered to consist of three elementary components, i.e., single crystalline GaN grains, pores (voids), and inter-granulated materials (amorphous GaN clusters). Such a polycrystalline nature of the GaN/Si(001) films was confirmed by scanning electron microscopy measurements. It was demonstrated that based on the proposed three-component effective medium model, excellent overall simulation of the RT-IRR spectra can be achieved, and the fine structures of the GaN reststrahlen band in the measured RT-IRR spectra can also be interpreted very well. Furthermore, the volume fraction for each component in the GaN/Si(001) film was accurately determined by fitting the experimental RT-IRR spectra with the theoretical simulation. These results indicate that IRR spectroscopy can offer a sensitive and convenient tool to probe the microstructure of GaN films grown on silicon. [copyright] 2001 American Institute of Physics

  11. On the prediction of threshold friction velocity of wind erosion using soil reflectance spectroscopy

    Science.gov (United States)

    Li, Junran; Flagg, Cody B.; Okin, Gregory S.; Painter, Thomas H.; Dintwe, Kebonye; Belnap, Jayne

    2015-01-01

    Current approaches to estimate threshold friction velocity (TFV) of soil particle movement, including both experimental and empirical methods, suffer from various disadvantages, and they are particularly not effective to estimate TFVs at regional to global scales. Reflectance spectroscopy has been widely used to obtain TFV-related soil properties (e.g., moisture, texture, crust, etc.), however, no studies have attempted to directly relate soil TFV to their spectral reflectance. The objective of this study was to investigate the relationship between soil TFV and soil reflectance in the visible and near infrared (VIS–NIR, 350–2500 nm) spectral region, and to identify the best range of wavelengths or combinations of wavelengths to predict TFV. Threshold friction velocity of 31 soils, along with their reflectance spectra and texture were measured in the Mojave Desert, California and Moab, Utah. A correlation analysis between TFV and soil reflectance identified a number of isolated, narrow spectral domains that largely fell into two spectral regions, the VIS area (400–700 nm) and the short-wavelength infrared (SWIR) area (1100–2500 nm). A partial least squares regression analysis (PLSR) confirmed the significant bands that were identified by correlation analysis. The PLSR further identified the strong relationship between the first-difference transformation and TFV at several narrow regions around 1400, 1900, and 2200 nm. The use of PLSR allowed us to identify a total of 17 key wavelengths in the investigated spectrum range, which may be used as the optimal spectral settings for estimating TFV in the laboratory and field, or mapping of TFV using airborne/satellite sensors.

  12. Simulation of attenuated total reflection infrared absorbance spectra: applications to automotive clear coat forensic analysis.

    Science.gov (United States)

    Lavine, Barry K; Fasasi, Ayuba; Mirjankar, Nikhil; Nishikida, Koichi; Campbell, Jay

    2014-01-01

    Attenuated total reflection (ATR) is a widely used sampling technique in infrared (IR) spectroscopy because minimal sample preparation is required. Since the penetration depth of the ATR analysis beam is quite shallow, the outer layers of a laminate or multilayered paint sample can be preferentially analyzed with the entire sample intact. For this reason, forensic laboratories are taking advantage of ATR to collect IR spectra of automotive paint systems that may consist of three or more layers. However, the IR spectrum of a paint sample obtained by ATR will exhibit distortions, e.g., band broadening and lower relative intensities at higher wavenumbers, compared with its transmission counterpart. This hinders library searching because most library spectra are measured in transmission mode. Furthermore, the angle of incidence for the internal reflection element, the refractive index of the clear coat, and surface contamination due to inorganic contaminants can profoundly influence the quality of the ATR spectrum obtained for automotive paints. A correction algorithm to allow ATR spectra to be searched using IR transmission spectra of the paint data query (PDQ) automotive database is presented. The proposed correction algorithm to convert transmission spectra from the PDQ library to ATR spectra is able to address distortion issues such as the relative intensities and broadening of the bands, and the introduction of wavelength shifts at lower frequencies, which prevent library searching of ATR spectra using archived IR transmission data.

  13. Generation of pulsed far-infrared radiation and its application for far-infrared time-resolved spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Yasuhiro [Tohoku Univ., Sendai (Japan). Faculty of Engineering

    1996-07-01

    So-called time-resolved spectroscopy technique has been used from old time as the means for studying the dynamic optical property, light-induced reaction and so on of matters. As an example, there is the method called pump and probe, and here, the wavelength of this probe light is the problem. If the object energy region is limited to about 0.1 eV, fast time-resolved spectroscopy is feasible relatively easily. However, energy region is extended to low energy region, the light source which is available as the pulsed probe light having sufficient intensity is limited. In this paper, the attempt of time-resolved spectroscopy utilizing coherent radiation, which has ended in failure, and the laser pulse-induced far-infrared radiation which can be utilized as new far-infrared probe light are reported. The reason why far-infrared radiation is used is explained. The attempt of time-resolved spectroscopy using NaCl crystals is reported on the equipment, the method of measuring absorption spectra and the results. Laser pulse-induced far-infrared radiation and the method of generating it are described. The multi-channel detector for far-infrared radiation which was made for trial is shown. (K.I.)

  14. Study on the surface hydroxyl group on solid breeding materials by infrared absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Satoru; Taniguchi, Masaki [Tokyo Univ. (Japan). Faculty of Engineering

    1996-10-01

    Hydroxyl groups on the surface of Li{sub 2}O were studied by using a diffuse reflectance method with Fourier transform infrared absorption spectroscopy at high temperature up to 973K under controlled D{sub 2}O or D{sub 2} partial pressure. It was found that hydroxyl groups could exist on Li{sub 2}O surface up to 973K under Ar atmosphere. Under D{sub 2}O containing atmosphere, only the sharp peak at 2520cm{sup -1} was observed at 973K in the O-D stretching vibration region. Below 973K, multiple peaks due to the surface -OD were observed and they showed different behavior with temperature or atmosphere. Multiple peaks mean that surface is not homogeneous for D{sub 2}O adsorption. Assignment of the observed peaks to the surface bonding structure was also discussed. (author)

  15. Fourier-transform infrared spectroscopy for rapid screening and live-cell monitoring: application to nanotoxicology.

    Science.gov (United States)

    Sundaram, S K; Sacksteder, Colette A; Weber, Thomas J; Riley, Brian J; Addleman, R Shane; Harrer, Bruce J; Peterman, John W

    2013-01-01

    A significant challenge to realize the full potential of nanotechnology for therapeutic and diagnostic applications is to understand and evaluate how live cells interact with an external stimulus, such as a nanosized particle, and the toxicity and broad risk associated with these stimuli. It is difficult to capture the complexity and dynamics of these interactions by following omics-based approaches exclusively, which can be expensive and time-consuming. Attenuated total reflectance-Fourier transform infrared spectroscopy is well suited to provide noninvasive live-cell monitoring of cellular responses to potentially toxic nanosized particles or other stimuli. This alternative approach provides the ability to carry out rapid toxicity screenings and nondisruptive monitoring of live-cell cultures. We review the technical basis of the approach, the instrument configuration and interface with the biological media, the various effects that impact the data, subsequent data analysis and toxicity, and present some preliminary results on live-cell monitoring.

  16. CHARACTERIZATION OF WOOD DECAY BY ROT FUNGI USING COLORIMETRY AND INFRARED SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    Mírian de Almeida Costa

    2011-09-01

    Full Text Available Wood samples of marupá (Simarouba amara and andiroba (Carapa guianenis were submitted to Trametes versicolor (white rot and Gloeophylum trabeum (brown rot fungi attack. Colorimetry was used to determine the color of the wood before and after wood decaying fungi. To evaluate the changes in chemical compounds levels in the wood samples, the diffuse reflectance medium infrared spectroscopy was used. Both wood were non resistant against white rot fungus, while with brown rot attack andiroba was resistant and marupá was not. After Gloeophyllum trabeum attack both woods changed to a darken color, and after Trametes versicolor attack andiroba changed to a lighter color and marupá darkened slightly, The analysis showed a reduction in the peak intensity of cellulose, hemicellulose and lignin, for both species, after Trametes versicolor attack and a reduction in the peak intensity of cellulose after Gloeophyllum trabeum attack.

  17. Infrared absorption spectroscopy and chemical kinetics of free radicals

    International Nuclear Information System (INIS)

    Curl, R.F.; Glass, G.P.

    1991-01-01

    A new channel producing ketenyl radical (HCCO) was discovered in the flash photolysis of ketene at 193 nm. H 2 CCO + hν(193 nm) → H + HCCO by observation near 2020 cm -1 of the infrared fundamental of ketenyl corresponding to the antisymmetric motion of the heavy atoms. This band has been partially rotationally analyzed and the rate constant for the reaction of ketenyl with NO has been determined. The OH stretching fundamental of hydroxymethyl radical (CH 2 OH) has been observed near 3600 cm -1 producing the radical either by the excimer flash photolysis of acetol (CH 3 COCH 2 OH) or by Cl atom abstraction of a methyl hydrogen from methanol. The assignment of the spectrum to CH 2 OH was confirmed by the agreement of the rate constant for the reaction of the species with O 2 with the literature value. The mechanism of the reaction of C 2 H with O 2 has been explored. There appear to be two channels producing CO product: a fast, direct one producing highly vibrationally excited CO up to v = 6 at the same rate C 2 H disappears and a slow, indirect one producing primarily ground state CO on a much longer timescale than the disappearance of C 2 H. The rate constants for the reactions of C 2 H with CH 4 , C 2 H 6 , C 2 H 4 , D 2 , and CO were determined by following the time decay of a C 2 H infrared transient absorption line originating from the ground vibronic state using diode laser spectroscopy creating the C 2 H by excimer laser flash photolysis (ArF, 193 nm) of CF 3 CCH. The branching ratio into OH of the reaction between NH 2 , and NO, which is the channel thought to propagate the radical chain of the Thermal deNOx process, has been measured up to 925 degree C. The OH yield thus obtained appears to be too small to maintain the process. 5 refs., 3 figs

  18. Application of Raman Spectroscopy and Infrared Spectroscopy in the Identification of Breast Cancer.

    Science.gov (United States)

    Depciuch, Joanna; Kaznowska, Ewa; Zawlik, Izabela; Wojnarowska, Renata; Cholewa, Marian; Heraud, Philip; Cebulski, Józef

    2016-02-01

    Raman spectroscopy and infrared (IR) spectroscopy are both techniques that allow for the investigation of vibrating chemical particles. These techniques provide information not only about chemical particles through the identification of functional groups and spectral analysis of so-called "fingerprints", these methods allow for the qualitative and quantitative analyses of chemical substances in the sample. Both of these spectral techniques are frequently being used in biology and medicine in diagnosing illnesses and monitoring methods of therapy. The type of breast cancer found in woman is often a malignant tumor, causing 1.38 million new cases of breast cancer and 458 000 deaths in the world in 2013. The most important risk factors for breast cancer development are: sex, age, family history, specific benign breast conditions in the breast, ionizing radiation, and lifestyle. The main purpose of breast cancer screening tests is to establish early diagnostics and to apply proper treatment. Diagnoses of breast cancer are based on: (1) physical techniques (e.g., ultrasonography, mammography, elastography, magnetic resonance, positron emission tomography [PET]); (2) histopathological techniques; (3) biological techniques; and (4) optical techniques (e.g., photo acoustic imaging, fluorescence tomography). However, none of these techniques provides unique or especially revealing answers. The aim of our study is comparative spectroscopic measurements on patients with the following: normal non-cancerous breast tissue; breast cancer tissues before chemotherapy; breast cancer tissues after chemotherapy; and normal breast tissues received around the cancerous breast region. Spectra collected from breast cancer patients shows changes in amounts of carotenoids and fats. We also observed changes in carbohydrate and protein levels (e.g., lack of amino acids, changes in the concentration of amino acids, structural changes) in comparison with normal breast tissues. This fact

  19. Site-Specific Characterization of Cytochrome P450cam Conformations by Infrared Spectroscopy.

    Science.gov (United States)

    Basom, Edward J; Maj, Michał; Cho, Minhaeng; Thielges, Megan C

    2016-06-21

    Conformational changes are central to protein function but challenging to characterize with both high spatial and temporal precision. The inherently fast time scale and small chromophores of infrared (IR) spectroscopy are well-suited for characterization of potentially rapidly fluctuating environments, and when frequency-resolved probes are incorporated to overcome spectral congestion, enable characterization of specific sites in proteins. We selectively incorporated p-cyanophenylalanine (CNF) as a vibrational probe at five distinct locations in the enzyme cytochrome P450cam and used IR spectroscopy to characterize the environments in substrate and/or ligand complexes reflecting those in the catalytic cycle. Molecular dynamics (MD) simulations were performed to provide a structural basis for spectral interpretation. Together the experimental and simulation data suggest that the CN frequencies are sensitive to both long-range influences, resulting from the particular location of a residue within the enzyme, as well as short-range influences from hydrogen bonding and packing interactions. The IR spectra demonstrate that the environments and effects of substrate and/or ligand binding are different at each position probed and also provide evidence that a single site can experience multiple environments. This study illustrates how IR spectroscopy, when combined with the spectral decongestion and spatial selectivity afforded by CNF incorporation, provides detailed information about protein structural changes that underlie function.

  20. Quantitative analysis of ice films by near-infrared spectroscopy

    Science.gov (United States)

    Keiser, Joseph T.

    1990-01-01

    One of the outstanding problems in the Space Transportation System is the possibility of the ice buildup on the external fuel tank surface while it is mounted on the launch pad. During the T-2 hours (and holding) period, the frost/ice thickness on the external tank is monitored/measured. However, after the resumption of the countdown time, the tank surface can only be monitored remotely. Currently, remote sensing is done with a TV camera coupled to a thermal imaging device. This device is capable of identifying the presence of ice, especially if it is covered with a layer of frost. However, it has difficulty identifying transparent ice, and, it is not capable of determining the thickness of ice in any case. Thus, there is a need for developing a technique for measuring the thickness of frost/ice on the tank surface during this two hour period before launch. The external tank surface is flooded with sunlight (natural or simulated) before launch. It may be possible, therefore, to analyze the diffuse reflection of sunlight from the external tank to determine the presence and thickness of ice. The purpose was to investigate the feasibility of this approach. A near-infrared spectrophotometer was used to record spectra of ice. It was determined that the optimum frequencies for monitoring the ice films were 1.03 and 1.255 microns.

  1. Nonlinear optics in germanium mid-infrared fiber material: Detuning oscillations in femtosecond mid-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    M. Ordu

    2017-09-01

    Full Text Available Germanium optical fibers hold great promise in extending semiconductor photonics into the fundamentally important mid-infrared region of the electromagnetic spectrum. The demonstration of nonlinear response in fabricated Ge fiber samples is a key step in the development of mid-infrared fiber materials. Here we report the observation of detuning oscillations in a germanium fiber in the mid-infrared region using femtosecond dispersed pump-probe spectroscopy. Detuning oscillations are observed in the frequency-resolved response when mid-infrared pump and probe pulses are overlapped in a fiber segment. The oscillations arise from the nonlinear frequency resolved nonlinear (χ(3 response in the germanium semiconductor. Our work represents the first observation of coherent oscillations in the emerging field of germanium mid-infrared fiber optics.

  2. Cryogenic Reflectance Spectroscopy in Support of Planetary Missions

    Science.gov (United States)

    Dalton, J. B.

    2002-01-01

    Present understanding of planetary composition is based primarily on remotely-sensed data, and in particular upon ultraviolet, visible, and infrared spectroscopy. Spectra acquired by telescopic and spacecraft instruments are compared to laboratory measurements of pure materials in order to identify surface components based on characteristic absorption features. Cryogenic spectral measurements are necessary for the study of worlds beyond the Earth's orbit. While some materials exhibit only small spectral changes as a function of temperature, many others are strongly temperature-dependent. For example, hydrated salts exhibit different spectral behavior under conditions appropriate to Europa than at terrestrial temperatures. The icy satellites of the outer solar system contain significant quantities of volatile ices which do not even exist at standard temperature and pressure (STP). A comprehensive spectral database of ices and minerals covering a wide temperature range will have applications ranging from the study of comets and Kuiper Belt objects to outer planet satellites and the polar regions of Mars. Efforts are presently underway at NASA-Ames to develop capabilities which will contribute to such a database. As spacecraft instruments feature increasing spatial and spectral resolution, appropriate laboratory reference spectra become increasingly critical to accurate interpretation of the spacecraft data.

  3. Methanogenic activity tests by Infrared Tunable Diode Laser Absorption Spectroscopy.

    Science.gov (United States)

    Martinez-Cruz, Karla; Sepulveda-Jauregui, Armando; Escobar-Orozco, Nayeli; Thalasso, Frederic

    2012-10-01

    Methanogenic activity (MA) tests are commonly carried out to estimate the capability of anaerobic biomass to treat effluents, to evaluate anaerobic activity in bioreactors or natural ecosystems, or to quantify inhibitory effects on methanogenic activity. These activity tests are usually based on the measurement of the volume of biogas produced by volumetric, pressure increase or gas chromatography (GC) methods. In this study, we present an alternative method for non-invasive measurement of methane produced during activity tests in closed vials, based on Infrared Tunable Diode Laser Absorption Spectroscopy (MA-TDLAS). This new method was tested during model acetoclastic and hydrogenotrophic methanogenic activity tests and was compared to a more traditional method based on gas chromatography. From the results obtained, the CH(4) detection limit of the method was estimated to 60 ppm and the minimum measurable methane production rate was estimated to 1.09(.)10(-3) mg l(-1) h(-1), which is below CH(4) production rate usually reported in both anaerobic reactors and natural ecosystems. Additionally to sensitivity, the method has several potential interests compared to more traditional methods among which short measurements time allowing the measurement of a large number of MA test vials, non-invasive measurements avoiding leakage or external interferences and similar cost to GC based methods. It is concluded that MA-TDLAS is a promising method that could be of interest not only in the field of anaerobic digestion but also, in the field of environmental ecology where CH(4) production rates are usually very low. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Effect of mechanical optical clearing on near-infrared spectroscopy.

    Science.gov (United States)

    Idelson, Christopher R; Vogt, William C; King-Casas, Brooks; LaConte, Stephen M; Rylander, Christopher G

    2015-08-01

    Near-infrared Spectroscopy (NIRS) is a broadly utilized technology with many emerging applications including clinical diagnostics, sports medicine, and functional neuroimaging, to name a few. For functional brain imaging NIR light is delivered at multiple wavelengths through the scalp and skull to the brain to enable spatial oximetry measurements. Dynamic changes in brain oxygenation are highly correlated with neural stimulation, activation, and function. Unfortunately, NIRS is currently limited by its low spatial resolution, shallow penetration depth, and, perhaps most importantly, signal corruption due to light interactions with superficial non-target tissues such as scalp and skull. In response to these issues, we have combined the non-invasive and rapidly reversible method of mechanical tissue optical clearing (MOC) with a commercially available NIRS system. MOC utilizes a compressive loading force on tissue, causing the lateral displacement of blood and water, while simultaneously thinning the tissue. A MOC-NIRS Breath Hold Test displayed a ∼3.5-fold decrease in the time-averaged standard deviation between channels, consequentially promoting greater channel agreement. A Skin Pinch Test was implemented to negate brain and muscle activity from affecting the recorded signal. These results displayed a 2.5-3.0 fold increase in raw signal amplitude. Existing NIRS instrumentation has been further integrated within a custom helmet device to provide a uniform force distribution across the NIRS sensor array. These results showed a gradual decrease in time-averaged standard deviation among channels with an increase in applied pressure. Through these experiments, and the development of the MOC-NIRS helmet device, MOC appears to provide enhancement of NIRS technology beyond its current limitations. © 2015 Wiley Periodicals, Inc.

  5. Implanted near-infrared spectroscopy for cardiac monitoring

    Science.gov (United States)

    Bhunia, Sourav K.; Cinbis, Can

    2011-02-01

    Implanted Cardioverter Defibrillator (ICD) provides one of the most effective therapies for the prevention of sudden cardiac death, but also delivers some high voltage shocks inappropriately, causing morbidity and mortality. Implanted near-infrared spectroscopy (NIRS) may augment ICD arrhythmia detection by monitoring skeletal muscle perfusion. A two-wavelength, single-distance, continuous-wave implanted NIRS has been evaluated in-vivo. A weighted difference of the changes in attenuation at two wavelengths, across the isobestic point of the hemoglobin spectra, was taken to be the microvascular oxygenation trend indicator (O2 Index). Although the exact weight depends on the local vascular distribution and their oxygen levels, the hypothesis that a constant weight may be adequate for hemodynamic trending during short arrhythmic episodes, was tested. The sensor was implanted subcutaneously both on fresh tissue and inside scar tissue that formed around a pre-existing implant, in 3 animals each. Attenuations were recorded at 660 and 890 nm during normal sinus rhythm (NSR) and induced ventricular fibrillation (VF). The slope of the O2 Index over 10 seconds was computed for 7 NSR and 8 VF episodes in fresh and 13 NSR and 15 VF episodes in scar tissue pockets. The mean O2 Index slope was significantly different (p<0.0001) between NSR and VF rhythms for both the fresh and scar tissue pockets. Therefore implanted NIRS may be useful for preventing inappropriate detection of VF during electromagnetic interference, double counting of ECG T-wave as an R-wave, ICD lead failure, electrocardiographic aberrancy etc.

  6. Infrared spectroscopy of pollen identifies plant species and genus as well as environmental conditions.

    Directory of Open Access Journals (Sweden)

    Boris Zimmermann

    Full Text Available BACKGROUND: It is imperative to have reliable and timely methodologies for analysis and monitoring of seed plants in order to determine climate-related plant processes. Moreover, impact of environment on plant fitness is predominantly based on studies of female functions, while the contribution of male gametophytes is mostly ignored due to missing data on pollen quality. We explored the use of infrared spectroscopy of pollen for an inexpensive and rapid characterization of plants. METHODOLOGY: The study was based on measurement of pollen samples by two Fourier transform infrared techniques: single reflectance attenuated total reflectance and transmission measurement of sample pellets. The experimental set, with a total of 813 samples, included five pollination seasons and 300 different plant species belonging to all principal spermatophyte clades (conifers, monocotyledons, eudicots, and magnoliids. RESULTS: The spectroscopic-based methodology enables detection of phylogenetic variations, including the separation of confamiliar and congeneric species. Furthermore, the methodology enables measurement of phenotypic plasticity by the detection of inter-annual variations within the populations. The spectral differences related to environment and taxonomy are interpreted biochemically, specifically variations of pollen lipids, proteins, carbohydrates, and sporopollenins. The study shows large variations of absolute content of nutrients for congenital species pollinating in the same environmental conditions. Moreover, clear correlation between carbohydrate-to-protein ratio and pollination strategy has been detected. Infrared spectral database with respect to biochemical variation among the range of species, climate and biogeography will significantly improve comprehension of plant-environment interactions, including impact of global climate change on plant communities.

  7. Photon-Counting Microwave Kinetic Inductance Detectors (MKIDs) for High Resolution Far-Infrared Spectroscopy

    Data.gov (United States)

    National Aeronautics and Space Administration — We are developing ultrasensitive Microwave Kinetic Inductance Detectors (MKIDs) for high resolution far-infrared spectroscopy applications, with a long-term goal of...

  8. ARTIFICIAL NEURAL-NETWORK PREDICTIONS OF URINARY CALCULUS COMPOSITIONS ANALYZED WITH INFRARED-SPECTROSCOPY

    NARCIS (Netherlands)

    VOLMER, M; WOLTHERS, BG; METTING, HJ; DEHAAN, THY; COENEGRACHT, PMJ; VANDERSLIK, W

    Infrared (IR) spectroscopy is used to analyze urinary calculus (renal stone) constituents. However, interpretation of IR spectra for quantifying urinary calculus constituents in mixtures is difficult, requiring expert knowledge by trained technicians. In our laboratory IR spectra of unknown calculi

  9. Monitoring breast cancer treatment using a Fourier transform infrared spectroscopy-based computational model.

    Science.gov (United States)

    Depciuch, J; Kaznowska, E; Golowski, S; Koziorowska, A; Zawlik, I; Cholewa, M; Szmuc, K; Cebulski, J

    2017-09-05

    Breast cancer affects one in four women, therefore, the search for new diagnostic technologies and therapeutic approaches is of critical importance. This involves the development of diagnostic tools to facilitate the detection of cancer cells, which is useful for assessing the efficacy of cancer therapies. One of the major challenges for chemotherapy is the lack of tools to monitor efficacy during the course of treatment. Vibrational spectroscopy appears to be a promising tool for such a purpose, as it yields Fourier transformation infrared (FTIR) spectra which can be used to provide information on the chemical composition of the tissue. Previous research by our group has demonstrated significant differences between the infrared spectra of healthy, cancerous and post-chemotherapy breast tissue. Furthermore, the results obtained for three extreme patient cases revealed that the infrared spectra of post-chemotherapy breast tissue closely resembles that of healthy breast tissue when chemotherapy is effective (i.e., a good therapeutic response is achieved), or that of cancerous breast tissue when chemotherapy is ineffective. In the current study, we compared the infrared spectra of healthy, cancerous and post-chemotherapy breast tissue. Characteristic parameters were designated for the obtained spectra, spreading the function of absorbance using the Kramers-Kronig transformation and the best fit procedure to obtain Lorentz functions, which represent components of the bands. The Lorentz function parameters were used to develop a physics-based computational model to verify the efficacy of a given chemotherapy protocol in a given case. The results obtained using this model reflected the actual patient data retrieved from medical records (health improvement or no improvement). Therefore, we propose this model as a useful tool for monitoring the efficacy of chemotherapy in patients with breast cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. The Advantages of an Attenuated Total Internal Reflection Infrared Microspectroscopic Imaging Technique for the Analysis of Polymer Laminates.

    Science.gov (United States)

    Ling, Chen; Sommer, André J

    2015-06-01

    Until recently, the analysis of polymer laminates using infrared microspectroscopy involved the painstaking separation of individual layers by dissection or by obtaining micrometer thin cross-sections. The latter usually requires the expertise of an individual trained in microtomy and even then, the very structure of the laminate could affect the outcome of the spectral results. The recent development of attenuated total internal reflection (ATR) infrared microspectroscopy imaging has provided a new avenue for the analysis of these multilayer structures. This report compares ATR infrared microspectroscopy imaging with conventional transmission infrared microspectroscopy imaging. The results demonstrate that the ATR method offers improved spatial resolution, eliminates a variety of competing optical processes, and requires minimal sample preparation relative to transmission measurements. These advantages were illustrated using a polymer laminate consisting of 11 different layers whose thickness ranged in size from 4-20 μm. The spatial resolution achieved by using an ATR-FTIR (Fourier transform infrared spectroscopy) imaging technique was diffraction limited. Contrast in the ATR images was enhanced by principal component analysis.

  11. Tree Canopy Characterization for EO-1 Reflective and Thermal Infrared Validation Studies: Rochester, New York

    Science.gov (United States)

    Ballard, Jerrell R., Jr.; Smith, James A.

    2002-01-01

    The tree canopy characterization presented herein provided ground and tree canopy data for different types of tree canopies in support of EO-1 reflective and thermal infrared validation studies. These characterization efforts during August and September of 2001 included stem and trunk location surveys, tree structure geometry measurements, meteorology, and leaf area index (LAI) measurements. Measurements were also collected on thermal and reflective spectral properties of leaves, tree bark, leaf litter, soil, and grass. The data presented in this report were used to generate synthetic reflective and thermal infrared scenes and images that were used for the EO-1 Validation Program. The data also were used to evaluate whether the EO-1 ALI reflective channels can be combined with the Landsat-7 ETM+ thermal infrared channel to estimate canopy temperature, and also test the effects of separating the thermal and reflective measurements in time resulting from satellite formation flying.

  12. Fourier Transform Infrared Spectroscopy as a Tool in Analysis of Proteus mirabilis Endotoxins.

    Science.gov (United States)

    Żarnowiec, Paulina; Czerwonka, Grzegorz; Kaca, Wiesław

    2017-01-01

    Fourier transform infrared spectroscopy (FT-IR) was used to scan whole bacterial cells as well as lipopolysaccharides (LPSs, endotoxins) isolated from them. Proteus mirabilis cells, with chemically defined LPSs, served as a model for the ATR FT-IR method. The paper focuses on three steps of infrared spectroscopy: (1) sample preparation, (2) IR scanning, and (3) multivariate analysis of IR data (principal component analysis, PCA).

  13. Effect of motion artifacts and their correction on near-infrared spectroscopy oscillation data

    DEFF Research Database (Denmark)

    Selb, Juliette; Yücel, Meryem A; Phillip, Dorte

    2015-01-01

    Functional near-infrared spectroscopy is prone to contamination by motion artifacts (MAs). Motion correction algorithms have previously been proposed and their respective performance compared for evoked rain activation studies. We study instead the effect of MAs on "oscillation" data which...... in the frequency band around 0.1 and 0.04 Hz, suggesting a physiological origin for the difference. We emphasize the importance of considering MAs as a confounding factor in oscillation-based functional near-infrared spectroscopy studies....

  14. Quick detection and quantification of iron-cyanide complexes using fourier transform infrared spectroscopy

    International Nuclear Information System (INIS)

    Sut-Lohmann, Magdalena; Raab, Thomas

    2017-01-01

    The continuous release of persistent iron-cyanide (Fe-CN) complexes from various industrial sources poses a high hazard to the environment and indicates the necessity to analyze a considerable amount of samples. Conventional flow injection analysis (FIA) is a time and cost consuming method for cyanide (CN) determination. Thus, a rapid and economic alternative needs to be developed to quantify the Fe-CN complexes. 52 soil samples were collected at a former Manufactured Gas Plant (MGP) site in order to determine the feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS). Soil analysis revealed CN concentrations in a range from 8 to 14.809 mg kg −1 , where 97% was in the solid form (Fe 4 [Fe(CN) 6 ] 3 ), which is characterized by a single symmetrical CN band in the range 2092–2084 cm −1 . The partial least squares (PLS) calibration-validation model revealed IR response to CN tot which exceeds 2306 mg kg −1 (limit of detection, LOD). Leave-one-out cross-validation (LOO-CV) was performed on soil samples, which contained low CN tot (<900 mg kg −1 ). This improved the sensitivity of the model by reducing the LOD to 154 mg kg −1 . Finally, the LOO-CV conducted on the samples with CN tot  > 900 mg kg −1 resulted in LOD equal to 3751 mg kg −1 . It was found that FTIR spectroscopy provides the information concerning different CN species in the soil samples. Additionally, it is suitable for quantifying Fe-CN species in matrixes with CN tot  > 154 mg kg −1 . Thus, FTIR spectroscopy, in combination with the statistical approach applied here seems to be a feasible and quick method for screening of contaminated sites. - Highlights: • A protocol for a quick and cheap quantitative cyanide analysis in soil using FTIR is proposed. • Splitting of the data, resulting in low and high CN set, reduced the LOD and increased the sensitivity of the model. • Regression coefficients indicate positive response of IR frequencies to

  15. Near infrared observations of the visual reflection nebulae NGC 7023, NGC 2023, and NGC 2068

    International Nuclear Information System (INIS)

    Sellgren, K.

    1984-01-01

    The emission of the nebulae NGC 7023, 2023, and 2068 at visual wavelengths is due to reflected starlight. Recently the infrared emission of these nebulae has been found to consist not of reflected light, but rather to be due to some other emission process. Spectra of the infrared emission at nebular positions in NGC 7023 and NGC 2023 are shown. The infrared emission consists of a smooth continuum which extends at least from 1.25 to 4.8 μm, and strong emission features at 3.3 and 3.4μm. (author)

  16. Portable laser-induced breakdown spectroscopy/diffuse reflectance hybrid spectrometer for analysis of inorganic pigments

    Science.gov (United States)

    Siozos, Panagiotis; Philippidis, Aggelos; Anglos, Demetrios

    2017-11-01

    A novel, portable spectrometer, combining two analytical techniques, laser-induced breakdown spectroscopy (LIBS) and diffuse reflectance spectroscopy, was developed with the aim to provide an enhanced instrumental and methodological approach with regard to the analysis of pigments in objects of cultural heritage. Technical details about the hybrid spectrometer and its operation are presented and examples are given relevant to the analysis of paint materials. Both LIBS and diffuse reflectance spectra in the visible and part of the near infrared, corresponding to several neat mineral pigment samples, were recorded and the complementary information was used to effectively distinguish different types of pigments even if they had similar colour or elemental composition. The spectrometer was also employed in the analysis of different paints on the surface of an ancient pottery sherd demonstrating the capabilities of the proposed hybrid diagnostic approach. Despite its instrumental simplicity and compact size, the spectrometer is capable of supporting analytical campaigns relevant to archaeological, historical or art historical investigations, particularly when quick data acquisition is required in the context of surveys of large numbers of objects and samples.

  17. Using reflectance anisotropy spectroscopy to characterize capped silver nanostructures grown on silicon

    Energy Technology Data Exchange (ETDEWEB)

    Fleischer, K.; Jacob, J.; McGilp, J.F. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland); Chandola, S. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland); ISAS - Institute for Analytical Sciences, Department Berlin, Albert-Einstein-Strasse 9, 12489 Berlin (Germany); Esser, N. [ISAS - Institute for Analytical Sciences, Department Berlin, Albert-Einstein-Strasse 9, 12489 Berlin (Germany)

    2008-07-01

    Using the single domain Si(111)-3 x 1-Ag surface as a template, room temperature deposition of two or more monolayers of Ag leads to the formation of metallic nanostructures. Reflectance anisotropy spectroscopy (RAS) in the infrared (IR) spectral region is used to analyse the anisotropic conductivity of the structures. The anisotropy is found to be influenced by the offcut angle of the substrate, and hence the terrace width. The Ag nanostructures were capped with Si to form a near-IR transparent protecting layer. The samples are stable to exposure to ambient conditions for significant periods. The RAS spectra are compared to model calculations, which support the conclusion that the buried metallic Ag nanostructures survive the capping process. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Classification and structural analysis of live and dead salmonella cells using fourier transform infrared (FT-IR) spectroscopy and principle component analysis (PCA)

    Science.gov (United States)

    Fourier Transform Infrared Spectroscopy (FT-IR) was used to detect Salmonella typhimurium and Salmonella enteritidis foodborne bacteria and distinguish between live and dead cells of both serotypes. Bacteria were loaded individually on the ZnSe Attenuated Total Reflection (ATR) crystal surface and s...

  19. Multi-site and multi-depth near-infrared spectroscopy in a model of simulated (central) hypovolemia: Lower body negative pressure

    NARCIS (Netherlands)

    S.A. Bartels (Sebastiaan); R. Bezemer (Rick); F.J.W. Wallis de Vries (Floris); D.M.J. Milstein (Dan); A.A.P. Lima (Alexandre ); T.G.V. Cherpanath (Thomas); A.H. van den Meiracker (Anton); J. van Bommel (Jasper); M. Heger (Michal); J.M. Karemaker (John); C. Ince (Can)

    2011-01-01

    textabstractPurpose: To test the hypothesis that the sensitivity of near-infrared spectroscopy (NIRS) in reflecting the degree of (compensated) hypovolemia would be affected by the application site and probing depth. We simultaneously applied multi-site (thenar and forearm) and multi-depth (15-2.5

  20. Silicon oxide particle formation in RF plasmas investigated by infrared absorption spectroscopy and mass spectrometry

    NARCIS (Netherlands)

    Hollenstein, Ch.; Howling, A.A.; Courteille, C.; Magni, D.; Scholz, S.M.; Kroesen, G.M.W.; Simons, N.; de Zeeuw, W.; Schwarzenbach, W.

    1998-01-01

    In situ Fourier transform infrared absorption spectroscopy has been used to study the composition of particles formed and suspended in radio-frequency discharges of silane - oxygen-argon gas mixtures. The silane gas consumption was observed by infrared absorption. The stoichiometry of the produced

  1. Infrared and Raman spectroscopy: principles and spectral interpretation

    National Research Council Canada - National Science Library

    Larkin, Peter

    2011-01-01

    .... The book reviews basic principles, instrumentation, sampling methods, quantitative analysis, origin of group frequencies and qualitative interpretation using generalized Infrared (IR) and Raman spectra...

  2. Discrimination of different red wine by Fourier-transform infrared and two-dimensional infrared correlation spectroscopy

    Science.gov (United States)

    Zhang, Yan-ling; Chen, Jian-bo; Lei, Yu; Zhou, Qun; Sun, Su-qin; Noda, Isao

    2010-06-01

    Fourier-transform infrared spectroscopy (FT-IR) and two-dimensional infrared (2D IR) correlation spectroscopy were applied to analyze main components of liquid red wine with different sugar contents and volatilization residues of dry red wine from different manufactures. The infrared spectra, second derivative spectra of dry red wine show the typical peaks of alcohol, while the spectra of sweet wine are composed of the peaks of both alcohol and sugar, and the contribution of sugar enhanced as the increase of sugar content. Using principal component analysis (PCA) method, dry and sweet wine can be readily classified. Analysis of the infrared spectra of the volatilization residues of dry red wine samples from five different manufactures indicates that dry red wine may be composed of glycerol, carboxylic acids or esters and carboxyl ate, at the same time, different dry red wine show different characteristic peaks in the second derivative spectra and 2D IR correlation spectra, which can be used to discriminate the different manufactures and evaluate the quality of wine samples. The results suggested that infrared spectroscopy is a direct and effective method for the analysis of principle components of different red wines and discrimination of different red wines.

  3. Study of Kerogen Maturity using Transmission Fourier Transform Infrared Spectroscopy (FTIR)

    Science.gov (United States)

    Dang, S. T.

    2014-12-01

    Maturity of kerogen in shale governs the productivity and generation hydrocarbon type. There are generally two accepted methods to measure kerogen maturity; one is the measurement of vitrinite reflectance, %Ro, and another is the measurement of Tmax through pyrolysis. However, each of these techniques has its own limits; vitrinite reflectance measurement cannot be applied to marine shale and pre-Silurian shales, which lack plant materials. Furthermore, %Ro, requires the isolation and identification of vitrinite macerals and statistical measurements of at least 50 macerals. Tmax measurement is questionable for mature and post-mature samples. In addition, there are questions involving the effects of solvents on Tmax determinations. Fourier Transmission Infrared Spectroscopy, FTIR, can be applied for both qualitative and quantitative assessment on organics maturity in shale. The technique does not require separating organic matter or identifying macerals. A CH2/CH3 index, RCH, calculated from FTIR spectra is more objective than other measurements. The index increases with maturity (both natural maturation and synthetic maturation through hydrous and dry pyrolysis). The new maturity index RCH can be calibrated to vitrinite reflectance which allows the definition of the following values for levels of maturity: 1) immature—RCH > 1.6±0.2; 2) oil window-- 1.6±0.2 1.3±0.3; 3) wet gas window--1.3±0.3 1.13±0.05; and 4) dry gas window RCH < 1.13±0.05.

  4. Hemodynamic measurements in deep brain tissues of humans by near-infrared time-resolved spectroscopy

    Science.gov (United States)

    Suzuki, Hiroaki; Oda, Motoki; Yamaki, Etsuko; Suzuki, Toshihiko; Yamashita, Daisuke; Yoshimoto, Kenji; Homma, Shu; Yamashita, Yutaka

    2014-03-01

    Using near-infrared time-resolved spectroscopy (TRS), we measured the human head in transmittance mode to obtain the optical properties, tissue oxygenation, and hemodynamics of deep brain tissues in 50 healthy adult volunteers. The right ear canal was irradiated with 3-wavelengths of pulsed light (760, 795, and 835nm), and the photons passing through the human head were collected at the left ear canal. Optical signals with sufficient intensity could be obtained from 46 of the 50 volunteers. By analyzing the temporal profiles based on the photon diffusion theory, we successfully obtained absorption coefficients for each wavelength. The levels of oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (Hb), total hemoglobin (tHb), and tissue oxygen saturation (SO2) were then determined by referring to the hemoglobin spectroscopic data. Compared with the SO2 values for the forehead measurements in reflectance mode, the SO2 values of the transmittance measurements of the human head were approximately 10% lower, and tHb values of the transmittance measurements were always lower than those of the forehead reflectance measurements. Moreover, the level of hemoglobin and the SO2 were strongly correlated between the human head measurements in transmittance mode and the forehead measurements in the reflectance mode, respectively. These results demonstrated a potential application of this TRS system in examining deep brain tissues of humans.

  5. Quantitative analysis of bayberry juice acidity based on visible and near-infrared spectroscopy

    International Nuclear Information System (INIS)

    Shao Yongni; He Yong; Mao Jingyuan

    2007-01-01

    Visible and near-infrared (Vis/NIR) reflectance spectroscopy has been investigated for its ability to nondestructively detect acidity in bayberry juice. What we believe to be a new, better mathematic model is put forward, which we have named principal component analysis-stepwise regression analysis-backpropagation neural network (PCA-SRA-BPNN), to build a correlation between the spectral reflectivity data and the acidity of bayberry juice. In this model, the optimum network parameters,such as the number of input nodes, hidden nodes, learning rate, and momentum, are chosen by the value of root-mean-square (rms) error. The results show that its prediction statistical parameters are correlation coefficient (r) of 0.9451 and root-mean-square error of prediction(RMSEP) of 0.1168. Partial least-squares (PLS) regression is also established to compare with this model. Before doing this, the influences of various spectral pretreatments (standard normal variate, multiplicative scatter correction, S. Golay first derivative, and wavelet package transform) are compared. The PLS approach with wavelet package transform preprocessing spectra is found to provide the best results, and its prediction statistical parameters are correlation coefficient (r) of 0.9061 and RMSEP of 0.1564. Hence, these two models are both desirable to analyze the data from Vis/NIR spectroscopy and to solve the problem of the acidity prediction of bayberry juice. This supplies basal research to ultimately realize the online measurements of the juice's internal quality through this Vis/NIR spectroscopy technique

  6. Formation and Thermal Infrared Spectroscopy of Halite Crusts

    Science.gov (United States)

    Baldridge, A. M.; Christensen, P. R.

    2003-12-01

    Efflorescent salt crusts form as groundwater evaporates from capillary updraw of brine through sediment. Salts precipitate at the surface, coating and cementing the upper few layers of sediment. If enough brine is present to completely saturate and pond on top of the surface, halite will precipitate at the surface of the brine and settle out as layers of crystalline salt on top of the sediment. In playa environments, salts such as sulfates, carbonates and halides, and forms such crusts. In remote sensing studies of such surfaces, it is important to understand how the presence of salt crusts affects the spectral features of the surrounding sediment. This is especially true when the crusts form from a non-absorbing salt such as halite. Halite has been observed to exhibit unusual spectral properties in the thermal infrared. Specifically, granular mixtures of minerals with halite produced spectra in which the spectral features inverted form reflectivity, shifted to shorter wavelengths and the spectral contrast increased near absorption bands. However, in crusted surfaces, in which the halite cements, coats or overlays the mineral grains, the presence of halite has a different affect on the spectra. This work will examine the precipitation of halite and the formation of salt crusts for several sediment and brine mixtures. Laboratory measurements of thermal emission spectra for the crusts will be compared to previous studies for particulate mixtures of halite with minerals and well as to natural surface crusts. Detailed knowledge of such surfaces will allow for their discrimination and identification in terrestrial playa settings as well as in paleo-environments on Mars.

  7. Application of linear discriminant analysis and Attenuated Total Reflectance Fourier Transform Infrared microspectroscopy for diagnosis of colon cancer.

    Science.gov (United States)

    Khanmohammadi, Mohammadreza; Bagheri Garmarudi, Amir; Samani, Simin; Ghasemi, Keyvan; Ashuri, Ahmad

    2011-06-01

    Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) microspectroscopy was applied for detection of colon cancer according to the spectral features of colon tissues. Supervised classification models can be trained to identify the tissue type based on the spectroscopic fingerprint. A total of 78 colon tissues were used in spectroscopy studies. Major spectral differences were observed in 1,740-900 cm(-1) spectral region. Several chemometric methods such as analysis of variance (ANOVA), cluster analysis (CA) and linear discriminate analysis (LDA) were applied for classification of IR spectra. Utilizing the chemometric techniques, clear and reproducible differences were observed between the spectra of normal and cancer cases, suggesting that infrared microspectroscopy in conjunction with spectral data processing would be useful for diagnostic classification. Using LDA technique, the spectra were classified into cancer and normal tissue classes with an accuracy of 95.8%. The sensitivity and specificity was 100 and 93.1%, respectively.

  8. In Situ Focused Beam Reflectance Measurement (FBRM, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR and Raman Characterization of the Polymorphic Transformation of Carbamazepine

    Directory of Open Access Journals (Sweden)

    Sohrab Rohani

    2012-02-01

    Full Text Available The objective of this work was to study the polymorphic transformation of carbamazepine from Form II to Form III in 1-propanol during seeded isothermal batch crystallization. First, the pure Form II and Form III were obtained and characterized. Then their solubilities and metastable zone limits were measured by in-situ attenuated total reflectance Fourier transform infrared (ATR-FTIR spectroscopy and focused beam reflectance measurement (FBRM. A transition temperature at about 34.2 °C was deduced suggesting the enantiotropic nature of this compound over the studied temperature range. To quantify the polymorph ratio during the transformation process, a new in-situ quantitative method was developed to measure the fraction of Form II by Raman spectroscopy. Successful tracking of the nucleation of the stable form and the transformation from Form II to Form III during isothermal crystallization was achieved by Raman spectroscopy and FBRM. The results from these three in-situ techniques, FBRM, FTIR and Raman were consistent with each other. The results showed a strong dependency on the amount of seeds added during isothermal crystallization.

  9. Improving the performance of infrared reflective night curtains for warming field plots

    DEFF Research Database (Denmark)

    Bruhn, Dan; Larsen, Klaus S.; de Dato, Giovanbattista D.

    2013-01-01

    Infrared reflective (IR) curtains have been widely used to obtain passive nighttime warming in field ecosystem experiments in order to simulate and study climate warming effects on ecosystems. For any field installation with IR-reflective curtains in an ecosystem the achieved heating effect depen...

  10. NEAR-INFRARED SPECTROSCOPY OF POST-AGB STARS

    NARCIS (Netherlands)

    OUDMAIJER, RD; WATERS, LBFM; VANDERVEEN, WECJ; GEBALLE, TR

    The results of a medium resolution near-infrared spectral survey of 18 post-AGB candidate stars are presented. Most of the stars have near-infrared hydrogen lines in absorption, which is normal for their spectral types. Three stars, HD 101584, HD 179821 and HD 170756 have the CO first overtone bands

  11. Application of reflectance spectroscopies (FTIR-ATR & FT-NIR) coupled with multivariate methods for robust in vivo detection of begomovirus infection in papaya leaves

    Science.gov (United States)

    Haq, Quazi M. I.; Mabood, Fazal; Naureen, Zakira; Al-Harrasi, Ahmed; Gilani, Sayed A.; Hussain, Javid; Jabeen, Farah; Khan, Ajmal; Al-Sabari, Ruqaya S. M.; Al-khanbashi, Fatema H. S.; Al-Fahdi, Amira A. M.; Al-Zaabi, Ahoud K. A.; Al-Shuraiqi, Fatma A. M.; Al-Bahaisi, Iman M.

    2018-06-01

    Nucleic acid & serology based methods have revolutionized plant disease detection, however, they are not very reliable at asymptomatic stage, especially in case of pathogen with systemic infection, in addition, they need at least 1-2 days for sample harvesting, processing, and analysis. In this study, two reflectance spectroscopies i.e. Near Infrared reflectance spectroscopy (NIR) and Fourier-Transform-Infrared spectroscopy with Attenuated Total Reflection (FT-IR, ATR) coupled with multivariate exploratory methods like Principle Component Analysis (PCA) and Partial least square discriminant analysis (PLS-DA) have been deployed to detect begomovirus infection in papaya leaves. The application of those techniques demonstrates that they are very useful for robust in vivo detection of plant begomovirus infection. These methods are simple, sensitive, reproducible, precise, and do not require any lengthy samples preparation procedures.

  12. Application of reflectance spectroscopies (FTIR-ATR & FT-NIR) coupled with multivariate methods for robust in vivo detection of begomovirus infection in papaya leaves.

    Science.gov (United States)

    Haq, Quazi M I; Mabood, Fazal; Naureen, Zakira; Al-Harrasi, Ahmed; Gilani, Sayed A; Hussain, Javid; Jabeen, Farah; Khan, Ajmal; Al-Sabari, Ruqaya S M; Al-Khanbashi, Fatema H S; Al-Fahdi, Amira A M; Al-Zaabi, Ahoud K A; Al-Shuraiqi, Fatma A M; Al-Bahaisi, Iman M

    2018-06-05

    Nucleic acid & serology based methods have revolutionized plant disease detection, however, they are not very reliable at asymptomatic stage, especially in case of pathogen with systemic infection, in addition, they need at least 1-2days for sample harvesting, processing, and analysis. In this study, two reflectance spectroscopies i.e. Near Infrared reflectance spectroscopy (NIR) and Fourier-Transform-Infrared spectroscopy with Attenuated Total Reflection (FT-IR, ATR) coupled with multivariate exploratory methods like Principle Component Analysis (PCA) and Partial least square discriminant analysis (PLS-DA) have been deployed to detect begomovirus infection in papaya leaves. The application of those techniques demonstrates that they are very useful for robust in vivo detection of plant begomovirus infection. These methods are simple, sensitive, reproducible, precise, and do not require any lengthy samples preparation procedures. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Analysis of Chuanxiong Rhizoma and its active components by Fourier transform infrared spectroscopy combined with two-dimensional correlation infrared spectroscopy.

    Science.gov (United States)

    Guo, Yizhen; Lv, Beiran; Wang, Jingjuan; Liu, Yang; Sun, Suqin; Xiao, Yao; Lu, Lina; Xiang, Li; Yang, Yanfang; Qu, Lei; Meng, Qinghong

    2016-01-15

    As complicated mixture systems, active components of Chuanxiong Rhizoma are very difficult to identify and discriminate. In this paper, the macroscopic IR fingerprint method including Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR), was applied to study and identify Chuanxiong raw materials and its different segmented production of HPD-100 macroporous resin. Chuanxiong Rhizoma is rich in sucrose. In the FT-IR spectra, water eluate is more similar to sucrose than the powder and the decoction. Their second derivative spectra amplified the differences and revealed the potentially characteristic IR absorption bands and combined with the correlation coefficient, concluding that 50% ethanol eluate had more ligustilide than other eluates. Finally, it can be found from 2DCOS-IR spectra that proteins were extracted by ethanol from Chuanxiong decoction by HPD-100 macroporous resin. It was demonstrated that the above three-step infrared spectroscopy could be applicable for quick, non-destructive and effective analysis and identification of very complicated and similar mixture systems of traditional Chinese medicines. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Chemical profiling and adulteration screening of Aquilariae Lignum Resinatum by Fourier transform infrared (FT-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy

    Science.gov (United States)

    Qu, Lei; Chen, Jian-bo; Zhang, Gui-Jun; Sun, Su-qin; Zheng, Jing

    2017-03-01

    As a kind of expensive perfume and valuable herb, Aquilariae Lignum Resinatum (ALR) is often adulterated for economic motivations. In this research, Fourier transform infrared (FT-IR) spectroscopy is employed to establish a simple and quick method for the adulteration screening of ALR. First, the principal chemical constituents of ALR are characterized by FT-IR spectroscopy at room temperature and two-dimensional correlation infrared (2D-IR) spectroscopy with thermal perturbation. Besides the common cellulose and lignin compounds, a certain amount of resin is the characteristic constituent of ALR. Synchronous and asynchronous 2D-IR spectra indicate that the resin (an unstable secondary metabolite) is more sensitive than cellulose and lignin (stable structural constituents) to the thermal perturbation. Using a certified ALR sample as the reference, the infrared spectral correlation threshold is determined by 30 authentic samples and 6 adulterated samples. The spectral correlation coefficient of an authentic ALR sample to the standard reference should be not less than 0.9886 (p = 0.01). Three commercial adulterated ALR samples are identified by the correlation threshold. Further interpretation of the infrared spectra of the adulterated samples indicates the common adulterating methods - counterfeiting with other kind of wood, adding ingredient such as sand to increase the weight, and adding the cheap resin such as rosin to increase the content of resin compounds. Results of this research prove that FT-IR spectroscopy can be used as a simple and accurate quality control method of ALR.

  15. Near infrared spectroscopy for determination of various physical, chemical and biochemical properties in Mediterranean soils.

    Science.gov (United States)

    Zornoza, R; Guerrero, C; Mataix-Solera, J; Scow, K M; Arcenegui, V; Mataix-Beneyto, J

    2008-07-01

    The potential of near infrared (NIR) reflectance spectroscopy to predict various physical, chemical and biochemical properties in Mediterranean soils from SE Spain was evaluated. Soil samples (n=393) were obtained by sampling thirteen locations during three years (2003-2005 period). These samples had a wide range of soil characteristics due to variations in land use, vegetation cover and specific climatic conditions. Biochemical properties also included microbial biomarkers based on phospholipid fatty acids (PLFA). Partial least squares (PLS) regression with cross validation was used to establish relationships between the NIR spectra and the reference data from physical, chemical and biochemical analyses. Based on the values of coefficient of determination (r(2)) and the ratio of standard deviation of validation set to root mean square error of cross validation (RPD), predicted results were evaluated as excellent (r(2)>0.90 and RPD>3) for soil organic carbon, Kjeldahl nitrogen, soil moisture, cation exchange capacity, microbial biomass carbon, basal soil respiration, acid phosphatase activity, β-glucosidase activity and PLFA biomarkers for total bacteria, Gram positive bacteria, actinomycetes, vesicular-arbuscular mycorrhizal fungi and total PLFA biomass. Good predictions (0.81fungi were not accurate enough to satisfactorily estimate these variables, only permitting approximate predictions (0.66reflect that NIR reflectance spectroscopy could be used as a rapid, inexpensive and non-destructive technique to predict some physical, chemical and biochemical soil properties for Mediterranean soils, including variables related to the composition of the soil microbial community composition.

  16. TIME-RESOLVED INFRARED SPECTROSCOPY IN THE U121R BEAMLINE AT THE NSLS

    International Nuclear Information System (INIS)

    CARR, G.L.; LAVEIGNE, J.D.; LOBO, R.P.S.M.; REITZE, D.H.; TANNER, D.B.

    1999-01-01

    A facility for performing time-resolved infrared spectroscopy has been developed at the NSLS, primarily at beamline U12IR. The pulsed IR light from the synchrotron is used to perform pump-probe spectroscopy. The authors present here a description of the facility and results for the relaxation of photoexcitations in both a semiconductor and superconductor

  17. Species authentication and geographical origin discrimination of herbal medicines by near infrared spectroscopy: A review.

    Science.gov (United States)

    Wang, Pei; Yu, Zhiguo

    2015-10-01

    Near infrared (NIR) spectroscopy as a rapid and nondestructive analytical technique, integrated with chemometrics, is a powerful process analytical tool for the pharmaceutical industry and is becoming an attractive complementary technique for herbal medicine analysis. This review mainly focuses on the recent applications of NIR spectroscopy in species authentication of herbal medicines and their geographical origin discrimination.

  18. Far infrared and terahertz spectroscopy of ferroelectric soft modes in thin films: a review

    Czech Academy of Sciences Publication Activity Database

    Petzelt, Jan; Kamba, Stanislav

    2016-01-01

    Roč. 503, č. 1 (2016), s. 19-44 ISSN 0015-0193 R&D Projects: GA ČR GA15-08389S Institutional support: RVO:68378271 Keywords : soft mode * central mode * ferroelectric thin film * terahertz spectroscopy * far-infrared spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.551, year: 2016

  19. A rapid identification of four medicinal chrysanthemum varieties with near infrared spectroscopy.

    Science.gov (United States)

    Han, Bangxing; Yan, Hui; Chen, Cunwu; Yao, Houjun; Dai, Jun; Chen, Naifu

    2014-07-01

    For genuine medicinal material in Chinese herbs; the efficient, rapid, and precise identification is the focus and difficulty in the filed studying Chinese herbal medicines. Chrysanthemum morifolium as herbs has a long planting history in China, culturing high quality ones and different varieties. Different chrysanthemum varieties differ in quality, chemical composition, functions, and application. Therefore, chrysanthemum varieties in the market demands precise identification to provide reference for reasonable and correct application as genuine medicinal material. A total of 244 batches of chrysanthemum samples were randomly divided into calibration set (160 batches) and prediction set (84 batches). The near infrared diffuses reflectance spectra of chrysanthemum varieties were preprocessed by first order derivative (D1) and autoscaling and was built model with partial least squares (PLS). In this study of four chrysanthemum varieties identification, the accuracy rates in calibration sets of Boju, Chuju, Hangju, and Gongju are respectively 100, 100, 98.65, and 96.67%; while the accuracy rates in prediction sets are 100% except for 99.1% of Hangju. The research results demonstrate that the qualitative analysis can be conducted by machine learning combined with near infrared spectroscopy (NIR), which provides a new method for rapid and noninvasive identification of chrysanthemum varieties.

  20. ASTM clustering for improving coal analysis by near-infrared spectroscopy.

    Science.gov (United States)

    Andrés, J M; Bona, M T

    2006-11-15

    Multivariate analysis techniques have been applied to near-infrared (NIR) spectra coals to investigate the relationship between nine coal properties (moisture (%), ash (%), volatile matter (%), fixed carbon (%), heating value (kcal/kg), carbon (%), hydrogen (%), nitrogen (%) and sulphur (%)) and the corresponding predictor variables. In this work, a whole set of coal samples was grouped into six more homogeneous clusters following the ASTM reference method for classification prior to the application of calibration methods to each coal set. The results obtained showed a considerable improvement of the error determination compared with the calibration for the whole sample set. For some groups, the established calibrations approached the quality required by the ASTM/ISO norms for laboratory analysis. To predict property values for a new coal sample it is necessary the assignation of that sample to its respective group. Thus, the discrimination and classification ability of coal samples by Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) in the NIR range was also studied by applying Soft Independent Modelling of Class Analogy (SIMCA) and Linear Discriminant Analysis (LDA) techniques. Modelling of the groups by SIMCA led to overlapping models that cannot discriminate for unique classification. On the other hand, the application of Linear Discriminant Analysis improved the classification of the samples but not enough to be satisfactory for every group considered.

  1. The spatial distribution of infrared radiation from visible reflection nebulae

    Science.gov (United States)

    Luan, Ling; Werner, Michael W.; Dwek, Eli; Sellgren, Kris

    1989-01-01

    The emission at IRAS 12 and 25 micron bands of reflection nebulae is far in excess of that expected from the longer wavelength equilibrium thermal emission. The excess emission in the IRAS 12 micron band is a general phenomenon, seen in various components of interstellar medium such as IR cirrus clouds, H II regions, atomic and molecular clouds, and also normal spiral galaxies. This excess emission has been attributed to UV excited fluorescence in polycyclic aromatic hydrocarbon (PAH) molecules or to the effect of temperature fluctuations in very small grains. Results are presented of studies of IRAS data on reflection nebulae selected from the van den Bergh reflection nebulae sample. Detailed scans of flux ratio and color temperature across the nebulae were obtained in order to study the spatial distribution of IR emission. A model was used to predict the spatial distribution of IR emission from dust grains illuminated by a B type star. The model was also used to explore the excitation of the IRAS 12 micron band emission as a function of stellar temperature. The model predictions are in good agreement with the analysis of reflection nebulae, illuminated by stars with stellar temperature ranging from 21,000 down to 3,000 K.

  2. Infrared reflection properties and modelling of in situ reflection measurements on plasma-facing materials in Tore Supra

    International Nuclear Information System (INIS)

    Reichle, R; Desgranges, C; Faisse, F; Pocheau, C; Lasserre, J-P; Oelhoffen, F; Eupherte, L; Todeschini, M

    2009-01-01

    Tore Supra has-like ITER-reflecting internal surfaces, which can perturb the machine protection systems based on infrared (IR) thermography. To ameliorate this situation, we have measured and modelled in the 3-5 μm wavelength range the bi-directional reflection distribution function (BRDF) of wall material samples from Tore Supra and conducted in situ reflection measurements and simulated them with the CEA COSMOS code. BRDF results are presented for B 4 C and carbon fibre composite (CFC) tiles. The hemispherical integrated reflection ranges from 0.12 for the B 4 C sample to 0.39 for a CFC tile from the limiter erosion zone. In situ measurements of the IR reflection of a blackbody source off an ICRH and an LHCD antenna of Tore Supra are well reproduced by the simulation.

  3. Infrared reflection properties and modelling of in situ reflection measurements on plasma-facing materials in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Reichle, R; Desgranges, C; Faisse, F; Pocheau, C [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Lasserre, J-P; Oelhoffen, F; Eupherte, L; Todeschini, M [CEA, DAM, CESTA, F-33114 Le Barp (France)

    2009-12-15

    Tore Supra has-like ITER-reflecting internal surfaces, which can perturb the machine protection systems based on infrared (IR) thermography. To ameliorate this situation, we have measured and modelled in the 3-5 {mu}m wavelength range the bi-directional reflection distribution function (BRDF) of wall material samples from Tore Supra and conducted in situ reflection measurements and simulated them with the CEA COSMOS code. BRDF results are presented for B{sub 4}C and carbon fibre composite (CFC) tiles. The hemispherical integrated reflection ranges from 0.12 for the B{sub 4}C sample to 0.39 for a CFC tile from the limiter erosion zone. In situ measurements of the IR reflection of a blackbody source off an ICRH and an LHCD antenna of Tore Supra are well reproduced by the simulation.

  4. An Overview of the Evolution of Infrared Spectroscopy Applied to Bacterial Typing.

    Science.gov (United States)

    Quintelas, Cristina; Ferreira, Eugénio C; Lopes, João A; Sousa, Clara

    2018-01-01

    The sustained emergence of new declared bacterial species makes typing a continuous challenge for microbiologists. Molecular biology techniques have a very significant role in the context of bacterial typing, but they are often very laborious, time consuming, and eventually fail when dealing with very closely related species. Spectroscopic-based techniques appear in some situations as a viable alternative to molecular methods with advantages in terms of analysis time and cost. Infrared and mass spectrometry are among the most exploited techniques in this context: particularly, infrared spectroscopy emerged as a very promising method with multiple reported successful applications. This article presents a systematic review on infrared spectroscopy applications for bacterial typing, highlighting fundamental aspects of infrared spectroscopy, a detailed literature review (covering different taxonomic levels and bacterial species), advantages, and limitations of the technique over molecular biology methods and a comparison with other competing spectroscopic techniques such as MALDI-TOF MS, Raman, and intrinsic fluorescence. Infrared spectroscopy possesses a high potential for bacterial typing at distinct taxonomic levels and worthy of further developments and systematization. The development of databases appears fundamental toward the establishment of infrared spectroscopy as a viable method for bacterial typing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Far Infrared spectroscopy of proteinogenic and other less common amino acids

    Science.gov (United States)

    Iglesias-Groth, S.; Cataldo, F.

    2018-05-01

    Far infrared spectroscopy is a powerful tool complementing the potential of mid infrared spectroscopy for the search and identification of organic molecules in space. The far infrared spectra of a total of 29 amino acids are reported in this study. In addition to the spectra of 20 common proteinogenic amino acids, spectra of a selection of 9 non-proteinogenic amino acids are also reported, including the 2-aminoisobutyric acid or α-aminoisobutyric acid which, with glycine, it is one of the most abundant amino acids found in meteorites. The present database of 29 far infrared spectra may serve as reference in the search for amino acids in space environments, given the new apportunities that JWST offers for mid and far IR spectroscopy.

  6. Optimisation of near-infrared reflectance model in measuring protein and amylose content of rice flour.

    Science.gov (United States)

    Xie, L H; Tang, S Q; Chen, N; Luo, J; Jiao, G A; Shao, G N; Wei, X J; Hu, P S

    2014-01-01

    Near-infrared reflectance spectroscopy (NIRS) has been used to predict the cooking quality parameters of rice, such as the protein (PC) and amylose content (AC). Using brown and milled flours from 519 rice samples representing a wide range of grain qualities, this study was to compare the calibration models generated by different mathematical, preprocessing treatments, and combinations of different regression algorithm. A modified partial least squares model (MPLS) with the mathematic treatment "2, 8, 8, 2" (2nd order derivative computed based on 8 data points, and 8 and 2 data points in the 1st and 2nd smoothing, respectively) and inverse multiplicative scattering correction preprocessing treatment was identified as the best model for simultaneously measurement of PC and AC in brown flours. MPLS/"2, 8, 8, 2"/detrend preprocessing was identified as the best model for milled flours. The results indicated that NIRS could be useful in estimation of PC and AC of breeding lines in early generations of the breeding programs, and for the purposes of quality control in the food industry. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Physiological response of Arundo donax to cadmium stress by Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Yu, Shunhui; Sheng, Li; Zhang, Chunyan; Deng, Hongping

    2018-06-05

    The present paper deals with the physiological response of the changes in chemical contents of the root, stem and leaf of Arundo donax seedlings stressed by excess cadmium using Fourier transform infrared spectroscopy technique, cadmium accumulation in plant by atomic absorption spectroscopy were tested after different concentrations cadmium stress. The results showed that low cadmium concentrations (Fourier transform infrared spectroscopy technique for the non-invasive and rapid monitoring of the plants stressed with heavy metals, Arundo donax is suitable for phytoremediation of cadmium -contaminated wetland. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Probing skin interaction with hydrogen peroxide using diffuse reflectance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zonios, George [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Dimou, Aikaterini [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Galaris, Dimitrios [Laboratory of Biological Chemistry, School of Medicine, University of Ioannina, 45110 Ioannina (Greece)

    2008-01-07

    Hydrogen peroxide is an important oxidizing agent in biological systems. In dermatology, it is frequently used as topical antiseptic, it has a haemostatic function, it can cause skin blanching, and it can facilitate skin tanning. In this work, we investigated skin interaction with hydrogen peroxide, non-invasively, using diffuse reflectance spectroscopy. We observed transient changes in the oxyhaemoglobin and deoxyhaemoglobin concentrations as a result of topical application of dilute H{sub 2}O{sub 2} solutions to the skin, with changes in deoxyhaemoglobin concentration being more pronounced. Furthermore, we did not observe any appreciable changes in melanin absorption properties as well as in the skin scattering properties. We also found no evidence for production of oxidized haemoglobin forms. Our observations are consistent with an at least partial decomposition of hydrogen peroxide within the stratum corneum and epidermis, with the resulting oxygen and/or remaining hydrogen peroxide inducing vasoconstriction to dermal blood vessels and increasing haemoglobin oxygen saturation. An assessment of the effects of topical application of hydrogen peroxide to the skin may serve as the basis for the development of non-invasive techniques to measure skin antioxidant capacity and also may shed light onto skin related disorders such as vitiligo.

  9. Probing skin interaction with hydrogen peroxide using diffuse reflectance spectroscopy

    International Nuclear Information System (INIS)

    Zonios, George; Dimou, Aikaterini; Galaris, Dimitrios

    2008-01-01

    Hydrogen peroxide is an important oxidizing agent in biological systems. In dermatology, it is frequently used as topical antiseptic, it has a haemostatic function, it can cause skin blanching, and it can facilitate skin tanning. In this work, we investigated skin interaction with hydrogen peroxide, non-invasively, using diffuse reflectance spectroscopy. We observed transient changes in the oxyhaemoglobin and deoxyhaemoglobin concentrations as a result of topical application of dilute H 2 O 2 solutions to the skin, with changes in deoxyhaemoglobin concentration being more pronounced. Furthermore, we did not observe any appreciable changes in melanin absorption properties as well as in the skin scattering properties. We also found no evidence for production of oxidized haemoglobin forms. Our observations are consistent with an at least partial decomposition of hydrogen peroxide within the stratum corneum and epidermis, with the resulting oxygen and/or remaining hydrogen peroxide inducing vasoconstriction to dermal blood vessels and increasing haemoglobin oxygen saturation. An assessment of the effects of topical application of hydrogen peroxide to the skin may serve as the basis for the development of non-invasive techniques to measure skin antioxidant capacity and also may shed light onto skin related disorders such as vitiligo

  10. Diffuse reflectance spectroscopy for the measurement of tissue oxygen saturation

    International Nuclear Information System (INIS)

    Sircan-Kucuksayan, A; Canpolat, M; Uyuklu, M

    2015-01-01

    Tissue oxygen saturation (StO 2 ) is a useful parameter for medical applications. A spectroscopic method has been developed to detect pathologic tissues, due to a lack of normal blood circulation, by measuring StO 2 . In this study, human blood samples with different levels of oxygen saturation have been prepared and spectra were acquired using an optical fiber probe to investigate the correlation between the oxygen saturation levels and the spectra. A linear correlation between the oxygen saturation and ratio of the intensities (760 nm to 790 nm) of the spectra acquired from blood samples has been found. In a validation study, oxygen saturations of the blood samples were estimated from the spectroscopic measurements with an error of 2.9%. It has also been shown that the linear dependence between the ratio and the oxygen saturation of the blood samples was valid for the blood samples with different hematocrits. Spectra were acquired from the forearms of 30 healthy volunteers to estimate StO 2 prior to, at the beginning of, after 2 min, and at the release of total vascular occlusion. The average StO 2 of a forearm before and after the two minutes occlusion was significantly different. The results suggested that optical reflectance spectroscopy is a sensitive method to estimate the StO 2 levels of human tissue. The technique developed to measure StO 2 has potential to detect ischemia in real time. (paper)

  11. Intramyocardial oxygen transport by quantitative diffuse reflectance spectroscopy in calves

    Science.gov (United States)

    Lindbergh, Tobias; Larsson, Marcus; Szabó, Zoltán; Casimir-Ahn, Henrik; Strömberg, Tomas

    2010-03-01

    Intramyocardial oxygen transport was assessed during open-chest surgery in calves by diffuse reflectance spectroscopy using a small intramuscular fiber-optic probe. The sum of hemo- and myoglobin tissue fraction and oxygen saturation, the tissue fraction and oxidation of cytochrome aa3, and the tissue fraction of methemoglobin were estimated using a calibrated empirical light transport model. Increasing the oxygen content in the inhaled gas, 21%-50%-100%, in five calves (group A) gave an increasing oxygen saturation of 19+/-4%, 24+/-5%, and 28+/-8% (panimals increased with LVAD pump speed (p<0.001, ANOVA) and with oxygen content in inhaled gas (p<0.001, ANOVA). The cytochrome aa3 oxidation level was above 96% in both group A and group B calves, including the two cases involving cardiac arrest. In conclusion, the estimated tissue fractions and oxygenation/oxidation levels of the myocardial chromophores during respiratory and hemodynamic provocations were in agreement with previously presented results, demonstrating the potential of the method.

  12. Physiological response of Arundo donax to cadmium stress by Fourier transform infrared spectroscopy

    Science.gov (United States)

    Yu, Shunhui; Sheng, Li; Zhang, Chunyan; Deng, Hongping

    2018-06-01

    The present paper deals with the physiological response of the changes in chemical contents of the root, stem and leaf of Arundo donax seedlings stressed by excess cadmium using Fourier transform infrared spectroscopy technique, cadmium accumulation in plant by atomic absorption spectroscopy were tested after different concentrations cadmium stress. The results showed that low cadmium concentrations (spectroscopy technique for the non-invasive and rapid monitoring of the plants stressed with heavy metals, Arundo donax is suitable for phytoremediation of cadmium -contaminated wetland.

  13. Detection of regulated herbs and plants in plant food supplements and traditional medicines using infrared spectroscopy.

    Science.gov (United States)

    Deconinck, E; Djiogo, C A Sokeng; Bothy, J L; Courselle, P

    2017-08-05

    The identification of a specific toxic or regulated plant in herbal preparations or plant food supplements is a real challenge, since they are often powdered, mixed with other herbal or synthetic powders and compressed into tablets or capsules. The classical identification approaches based on micro- and macroscopy are therefore not possible anymore. In this paper infrared spectroscopy, combined with attenuated total reflectance was evaluated for the screening of plant based preparations for nine specific plants (five regulated and four common plants for herbal supplements). IR and NIR spectra were recorded for a series of self-made triturations of the targeted plants. After pretreatment of the spectral data chemometric classification techniques were applied to both data sets (IR and NIR) separately and the combination of both. The results show that the screening of herbal preparations or plant food supplements for specific plants, using infrared spectroscopy, is feasible. The best model was obtained with the Mid-IR data, using SIMCA as modelling technique. During validation of the model, using an external test set, 21 of 25 were correctly classified and six of the nine targeted plants showed no misclassifications for the selected test set. For the other three a success rate of 50% was obtained. Mid-IR combined with SIMCA can therefore be applied as a first step in the screening of unknown samples, before applying more sophisticated fingerprint approaches or identification tests described in several national and international pharmacopoeia. As a proof of concept five real suspicious samples were successfully screened for the targeted regulated plants. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Effects of gamma irradiation on microhardness and Fourier Transform Infrared Spectroscopy of bovine bone

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Derly Augusto; Pereira, Daisa L.; Gomes, Gabriela V.; Sugahara, Vanessa M.L.; Mathor, Monica B.; Zezell, Denise Maria, E-mail: zezell@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro para Lasers e Aplicacoes

    2017-07-01

    The skeletal systems with the structural arrangement of the bone are very important for load distribution, mechanical resistance and vital organs protection. The bone structure is multiphase and composed of organic, inorganic (mineral) compounds and water. Gamma radiation is an ionizing radiation that comes from gamma radiation sources or X-ray generator is commonly used in health establishments such as radio diagnostic exams, radiotherapy and sterilization of allograft. The characterization of the irradiated bone tissue can be is an important tool to study of the components that are affected and how much each dose of ionizing radiation can alter its mechanical properties. This information will be very important in in vitro and ex vivo studies where sterilization of the bone material is necessary and may still be useful in understanding the effects on the bone tissue of patients undergoing short-term radiotherapy. For this, 110 samples of bovine femur diaphysis were randomized into 11 groups: G1 untreated (control); G2 to G11 were submitted to gamma irradiation ({sup 60}Co Gammacel). Samples were polished before irradiation and submitted to a Knoop Microhardness Test to determine the hardness of bovine bone and Fourier transform Infrared spectroscopy (FTIR) to biochemical characterization. Spectra were collected in the mid-infrared range in Attenuated Total Reflectance (ATR) sampling mode associated whit PCA multivariate technique to evaluate the molecular changes in bone matrix. It was observed that hardness was not altered by gamma irradiation and FTIR spectroscopy associated with PCA is a good method to analyze the changes in bone tissue submitted to ionizing radiation. (author)

  15. Effects of gamma irradiation on microhardness and Fourier Transform Infrared Spectroscopy of bovine bone

    International Nuclear Information System (INIS)

    Dias, Derly Augusto; Pereira, Daisa L.; Gomes, Gabriela V.; Sugahara, Vanessa M.L.; Mathor, Monica B.; Zezell, Denise Maria

    2017-01-01

    The skeletal systems with the structural arrangement of the bone are very important for load distribution, mechanical resistance and vital organs protection. The bone structure is multiphase and composed of organic, inorganic (mineral) compounds and water. Gamma radiation is an ionizing radiation that comes from gamma radiation sources or X-ray generator is commonly used in health establishments such as radio diagnostic exams, radiotherapy and sterilization of allograft. The characterization of the irradiated bone tissue can be is an important tool to study of the components that are affected and how much each dose of ionizing radiation can alter its mechanical properties. This information will be very important in in vitro and ex vivo studies where sterilization of the bone material is necessary and may still be useful in understanding the effects on the bone tissue of patients undergoing short-term radiotherapy. For this, 110 samples of bovine femur diaphysis were randomized into 11 groups: G1 untreated (control); G2 to G11 were submitted to gamma irradiation ("6"0Co Gammacel). Samples were polished before irradiation and submitted to a Knoop Microhardness Test to determine the hardness of bovine bone and Fourier transform Infrared spectroscopy (FTIR) to biochemical characterization. Spectra were collected in the mid-infrared range in Attenuated Total Reflectance (ATR) sampling mode associated whit PCA multivariate technique to evaluate the molecular changes in bone matrix. It was observed that hardness was not altered by gamma irradiation and FTIR spectroscopy associated with PCA is a good method to analyze the changes in bone tissue submitted to ionizing radiation. (author)

  16. Fourier transform near-infrared spectroscopy application for sea salt quality evaluation.

    Science.gov (United States)

    Galvis-Sánchez, Andrea C; Lopes, João Almeida; Delgadillo, Ivonne; Rangel, António O S S

    2011-10-26

    Near-infrared (NIR) spectroscopy in diffuse reflectance mode was explored with the objective of discriminating sea salts according to their quality type (traditional salt vs "flower of salt") and geographical origin (Atlantic vs Mediterranean). Sea salts were also analyzed in terms of Ca(2+), Mg(2+), K(+), alkalinity, and sulfate concentrations to support spectroscopic results. High concentrations of Mg(2+) and K(+) characterized Atlantic samples, while a high Ca(2+) content was observed in traditional sea salts. A partial least-squares discriminant analysis model considering the 8500-7500 cm(-1) region permitted the discrimination of salts by quality types. The regions 4650-4350 and 5900-5500 cm(-1) allowed salts classification according to their geographical origin. It was possible to classify correctly 85.3 and 94.8% of the analyzed samples according to the salt type and to the geographical origin, respectively. These results demonstrated that NIR spectroscopy is a suitable and very efficient tool for sea salt quality evaluation.

  17. Analysis of Moisture Content in Beetroot using Fourier Transform Infrared Spectroscopy and by Principal Component Analysis.

    Science.gov (United States)

    Nesakumar, Noel; Baskar, Chanthini; Kesavan, Srinivasan; Rayappan, John Bosco Balaguru; Alwarappan, Subbiah

    2018-05-22

    The moisture content of beetroot varies during long-term cold storage. In this work, we propose a strategy to identify the moisture content and age of beetroot using principal component analysis coupled Fourier transform infrared spectroscopy (FTIR). Frequent FTIR measurements were recorded directly from the beetroot sample surface over a period of 34 days for analysing its moisture content employing attenuated total reflectance in the spectral ranges of 2614-4000 and 1465-1853 cm -1 with a spectral resolution of 8 cm -1 . In order to estimate the transmittance peak height (T p ) and area under the transmittance curve [Formula: see text] over the spectral ranges of 2614-4000 and 1465-1853 cm -1 , Gaussian curve fitting algorithm was performed on FTIR data. Principal component and nonlinear regression analyses were utilized for FTIR data analysis. Score plot over the ranges of 2614-4000 and 1465-1853 cm -1 allowed beetroot quality discrimination. Beetroot quality predictive models were developed by employing biphasic dose response function. Validation experiment results confirmed that the accuracy of the beetroot quality predictive model reached 97.5%. This research work proves that FTIR spectroscopy in combination with principal component analysis and beetroot quality predictive models could serve as an effective tool for discriminating moisture content in fresh, half and completely spoiled stages of beetroot samples and for providing status alerts.

  18. Economical Appraisal of Total Aflatoxin Level in the Poultry Feeds by Fourier Transform Infrared Spectroscopy

    International Nuclear Information System (INIS)

    Sherazai, S.T.H.; Shar, Z.; Iqbal, M.; Sumbal, G.A.

    2013-01-01

    Single-bounce attenuated total reflectance (SB-ATR) Fourier transform infrared (FTIR) spectroscopy has been used for the quantitative determination of total aflatoxins in the broiler poultry feed. An FTIR calibration spanning the range 1-70 micro g/L aflatoxin standards in (70:30, v/v) methanol-water solvent system based on partial least square (PLS) model, developed by relating mid IR region between 3755-950 cm/ sub -1/. The excellent coefficient of various (using 0.998) was achieved with 1.49 relative mean square error of calibration (RMSEC). Aflatoxins from each of eight poultry feeds was extracted and the determined by the widely used commercially available Enzyme-linked Immunosorbent Assay (ELISA) procedure and the SB-ATR/FTIR method. The SB-ATR/FTIR aflatoxins predictions were related to those determined by the ELISA method by linear regression, producing an R value of 0.989 and a SD of +- 2.80 micro g/L. The result of the study clearly indicated that FT-IR spectroscopy due to its rapidity and simplicity along with data manipulation by advance computer software could be effectively used for routine determination of aflatoxins present in the poultry feeds at very low level. (author)

  19. Rapid Quantitative Analysis of Forest Biomass Using Fourier Transform Infrared Spectroscopy and Partial Least Squares Regression

    Directory of Open Access Journals (Sweden)

    Gifty E. Acquah

    2016-01-01

    Full Text Available Fourier transform infrared reflectance (FTIR spectroscopy has been used to predict properties of forest logging residue, a very heterogeneous feedstock material. Properties studied included the chemical composition, thermal reactivity, and energy content. The ability to rapidly determine these properties is vital in the optimization of conversion technologies for the successful commercialization of biobased products. Partial least squares regression of first derivative treated FTIR spectra had good correlations with the conventionally measured properties. For the chemical composition, constructed models generally did a better job of predicting the extractives and lignin content than the carbohydrates. In predicting the thermochemical properties, models for volatile matter and fixed carbon performed very well (i.e., R2 > 0.80, RPD > 2.0. The effect of reducing the wavenumber range to the fingerprint region for PLS modeling and the relationship between the chemical composition and higher heating value of logging residue were also explored. This study is new and different in that it is the first to use FTIR spectroscopy to quantitatively analyze forest logging residue, an abundant resource that can be used as a feedstock in the emerging low carbon economy. Furthermore, it provides a complete and systematic characterization of this heterogeneous raw material.

  20. Highly doped semiconductor plasmonic nanoantenna arrays for polarization selective broadband surface-enhanced infrared absorption spectroscopy of vanillin

    Science.gov (United States)

    Barho, Franziska B.; Gonzalez-Posada, Fernando; Milla, Maria-Jose; Bomers, Mario; Cerutti, Laurent; Tournié, Eric; Taliercio, Thierry

    2017-11-01

    Tailored plasmonic nanoantennas are needed for diverse applications, among those sensing. Surface-enhanced infrared absorption (SEIRA) spectroscopy using adapted nanoantenna substrates is an efficient technique for the selective detection of molecules by their vibrational spectra, even in small quantity. Highly doped semiconductors have been proposed as innovative materials for plasmonics, especially for more flexibility concerning the targeted spectral range. Here, we report on rectangular-shaped, highly Si-doped InAsSb nanoantennas sustaining polarization switchable longitudinal and transverse plasmonic resonances in the mid-infrared. For small array periodicities, the highest reflectance intensity is obtained. Large periodicities can be used to combine localized surface plasmon resonances (SPR) with array resonances, as shown in electromagnetic calculations. The nanoantenna arrays can be efficiently used for broadband SEIRA spectroscopy, exploiting the spectral overlap between the large longitudinal or transverse plasmonic resonances and narrow infrared active absorption features of an analyte molecule. We demonstrate an increase of the vibrational line intensity up to a factor of 5.7 of infrared-active absorption features of vanillin in the fingerprint spectral region, yielding enhancement factors of three to four orders of magnitude. Moreover, an optimized readout for SPR sensing is proposed based on slightly overlapping longitudinal and transverse localized SPR.

  1. Highly doped semiconductor plasmonic nanoantenna arrays for polarization selective broadband surface-enhanced infrared absorption spectroscopy of vanillin

    Directory of Open Access Journals (Sweden)

    Barho Franziska B.

    2017-11-01

    Full Text Available Tailored plasmonic nanoantennas are needed for diverse applications, among those sensing. Surface-enhanced infrared absorption (SEIRA spectroscopy using adapted nanoantenna substrates is an efficient technique for the selective detection of molecules by their vibrational spectra, even in small quantity. Highly doped semiconductors have been proposed as innovative materials for plasmonics, especially for more flexibility concerning the targeted spectral range. Here, we report on rectangular-shaped, highly Si-doped InAsSb nanoantennas sustaining polarization switchable longitudinal and transverse plasmonic resonances in the mid-infrared. For small array periodicities, the highest reflectance intensity is obtained. Large periodicities can be used to combine localized surface plasmon resonances (SPR with array resonances, as shown in electromagnetic calculations. The nanoantenna arrays can be efficiently used for broadband SEIRA spectroscopy, exploiting the spectral overlap between the large longitudinal or transverse plasmonic resonances and narrow infrared active absorption features of an analyte molecule. We demonstrate an increase of the vibrational line intensity up to a factor of 5.7 of infrared-active absorption features of vanillin in the fingerprint spectral region, yielding enhancement factors of three to four orders of magnitude. Moreover, an optimized readout for SPR sensing is proposed based on slightly overlapping longitudinal and transverse localized SPR.

  2. Visible and near-infrared spectroscopic analysis of raw milk for cow health monitoring: reflectance or transmittance?

    Science.gov (United States)

    Aernouts, B; Polshin, E; Lammertyn, J; Saeys, W

    2011-11-01

    The composition of produced milk has great value for the dairy farmer. It determines the economic value of the milk and provides valuable information about the metabolism of the corresponding cow. Therefore, online measurement of milk components during milking 2 or more times per day would provide knowledge about the current health and nutritional status of each cow individually. This information provides a solid basis for optimizing cow management. The potential of visible and near-infrared (Vis/NIR) spectroscopy for predicting the fat, crude protein, lactose, and urea content of raw milk online during milking was, therefore, investigated in this study. Two measurement modes (reflectance and transmittance) and different wavelength ranges for Vis/NIR spectroscopy were evaluated and their ability to measure the milk composition online was compared. The Vis/NIR reflectance measurements allowed for very accurate monitoring of the fat and crude protein content in raw milk (R(2)>0.95), but resulted in poor lactose predictions (R(2)milk samples gave accurate fat and crude protein predictions (R(2)>0.90) and useful lactose predictions (R(2)=0.88). Neither Vis/NIR reflectance nor transmittance spectroscopy lead to an acceptable prediction of the milk urea content. Transmittance spectroscopy can thus be used to predict the 3 major milk components, but with lower accuracy for fat and crude protein than the reflectance mode. Moreover, the small sample thickness (1mm) required for NIR transmittance measurement considerably complicates its online use. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  3. Far-infrared spectroscopy of thermally annealed tungsten silicide films

    International Nuclear Information System (INIS)

    Amiotti, M.; Borghesi, A.; Guizzetti, G.; Nava, F.; Santoro, G.

    1991-01-01

    The far-infrared transmittance spectrum of tungsten silicide has been observed for the first time. WSi 2 polycrystalline films were prepared by coevaporation and chemical-vapour deposition on silicon wafers, and subsequently thermally annealed at different temperatures. The observed structures are interpreted, on the basis of the symmetry properties of the crystal, such as infrared-active vibrational modes. Moreover, the marked lineshape dependence on annealing temperature enables this technique to analyse the formation of the solid silicide phases

  4. Far-infrared spectroscopy of neutral interstellar clouds

    International Nuclear Information System (INIS)

    Watson, D.M.

    1984-01-01

    A summary is presented of airborne observations of the far-infrared fine structure lines of neutral atomic oxygen and singly-ionized carbon, and of the far-infrared rotational lines of CO, OH, NH 3 and HD, together with a brief description of the analysis and interpretation of the spectra. The 'state of the art' in instrument performance and the prospects for improved sensitivity and resolution are also surveyed. (Auth.)

  5. Position Detection Based on Intensities of Reflected Infrared Light

    DEFF Research Database (Denmark)

    Christensen, Henrik Vie

    measurements of reflected light intensities, and includes easy calibration. The method for reconstructing 3D positions has been implemented in a prototype of a “non-Touch Screen” for a computer, so that the user can control a cursor in three dimensions by moving his/hers hand in front of the computer screen....... The 2D position reconstruction method is mplemented in a prototype of a human-machine interface (HMI) for an electrically powered wheelchair, such that the wheelchair user can control the movement of the wheelchair by head movements. Both “non-Touch Screen” prototype and wheelchair HMI has been tested...

  6. In Situ Infrared Spectroscopy of Oligoaniline Intermediates Created under Alkaline Conditions.

    Science.gov (United States)

    Šeděnková, Ivana; Stejskal, Jaroslav; Trchová, Miroslava

    2014-12-26

    The progress of the oxidation of aniline with ammonium peroxydisulfate in an alkaline aqueous medium has been monitored in situ by attenuated total reflection (ATR) Fourier transform infrared spectroscopy. The growth of the microspheres and of the film at the ATR crystal surface, as well as the changes proceeding in the surrounding aqueous medium, are reflected in the spectra. The evolution of the spectra and the changes in the molecular structure occurring during aniline oxidation in alkaline medium are discussed with the help of differential spectra. Several processes connected with the various stages of aniline oxidation were distinguished. The progress of hydrolysis of the aniline in water and further an oxidation of aminophenol to benzoquinone imines in the presence of peroxydisulfate in alkaline medium have been detected in the spectra in real time. The precipitated solid oxidation product was analyzed by mass spectrometry. It is composed of oligomers, mainly trimers to octamers, of various molecular structures incorporating in addition to aniline constitutional units also p-benzoquinone or p-benzoquinoneimine moieties.

  7. Fourier Transform Infrared Radiation Spectroscopy Applied for Wood Rot Decay and Mould Fungi Growth Detection

    Directory of Open Access Journals (Sweden)

    Bjørn Petter Jelle

    2012-01-01

    Full Text Available Material characterization may be carried out by the attenuated total reflectance (ATR Fourier transform infrared (FTIR radiation spectroscopical technique, which represents a powerful experimental tool. The ATR technique may be applied on both solid state materials, liquids, and gases with none or only minor sample preparations, also including materials which are nontransparent to IR radiation. This facilitation is made possible by pressing the sample directly onto various crystals, for example, diamond, with high refractive indices, in a special reflectance setup. Thus ATR saves time and enables the study of materials in a pristine condition, that is, the comprehensive sample preparation by pressing thin KBr pellets in traditional FTIR transmittance spectroscopy is hence avoided. Materials and their ageing processes, both ageing by natural and accelerated climate exposure, decomposition and formation of chemical bonds and products, may be studied in an ATR-FTIR analysis. In this work, the ATR-FTIR technique is utilized to detect wood rot decay and mould fungi growth on various building material substrates. An experimental challenge and aim is to be able to detect the wood rot decay and mould fungi growth at early stages when it is barely visible to the naked eye. Another goal is to be able to distinguish between various species of fungi and wood rot.

  8. Diffuse reflectance infrared Fourier-Transform spectra of selected organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, S.H.; Caton, J.E.

    1982-05-01

    Diffuse reflectance infrared spectra of a variety of different organic compounds have been determined. Profiles of the spectra along with the location and relative intensity of the principal bands have been included for each compound studied. In addition both diffuse reflectance and transmittance infrared spectra were obtained for the same samples, and the spectral results were compared. Although some minor variations are observed between a diffuse reflectance spectrum and the corresponding transmittance spectrum, the diffuse reflectance is quite useful and may be a superior technique for the study of many samples because it possesses an inherently higher signal-to-noise response, requires less sample preparation and allows a very wide range of samples (solids, liquids of low volatility, neat sample, or sample diluted in a reflecting medium) to be studied under very similar conditions.

  9. Near-infrared reflectance analysis by Gauss-Jordan linear algebra

    International Nuclear Information System (INIS)

    Honigs, D.E.; Freelin, J.M.; Hieftje, G.M.; Hirschfeld, T.B.

    1983-01-01

    Near-infrared reflectance analysis is an analytical technique that uses the near-infrared diffuse reflectance of a sample at several discrete wavelengths to predict the concentration of one or more of the chemical species in that sample. However, because near-infrared bands from solid samples are both abundant and broad, the reflectance at a given wavelength usually contains contributions from several sample components, requiring extensive calculations on overlapped bands. In the present study, these calculations have been performed using an approach similar to that employed in multi-component spectrophotometry, but with Gauss-Jordan linear algebra serving as the computational vehicle. Using this approach, correlations for percent protein in wheat flour and percent benzene in hydrocarbons have been obtained and are evaluated. The advantages of a linear-algebra approach over the common one employing stepwise regression are explored

  10. Diffuse Reflectance Spectroscopy for Surface Measurement of Liver Pathology.

    Science.gov (United States)

    Nilsson, Jan H; Reistad, Nina; Brange, Hannes; Öberg, Carl-Fredrik; Sturesson, Christian

    2017-01-01

    Liver parenchymal injuries such as steatosis, steatohepatitis, fibrosis, and sinusoidal obstruction syndrome can lead to increased morbidity and liver failure after liver resection. Diffuse reflectance spectroscopy (DRS) is an optical measuring method that is fast, convenient, and established. DRS has previously been used on the liver with an invasive technique consisting of a needle that is inserted into the parenchyma. We developed a DRS system with a hand-held probe that is applied to the liver surface. In this study, we investigated the impact of the liver capsule on DRS measurements and whether liver surface measurements are representative of the whole liver. We also wanted to confirm that we could discriminate between tumor and liver parenchyma by DRS. The instrumentation setup consisted of a light source, a fiber-optic contact probe, and two spectrometers connected to a computer. Patients scheduled for liver resection due to hepatic malignancy were included, and DRS measurements were performed on the excised liver part with and without the liver capsule and alongside a newly cut surface. To estimate the scattering parameters and tissue chromophore volume fractions, including blood, bile, and fat, the measured diffuse reflectance spectra were applied to an analytical model. In total, 960 DRS spectra from the excised liver tissue of 18 patients were analyzed. All factors analyzed regarding tumor versus liver tissue were significantly different. When measuring through the capsule, the blood volume fraction was found to be 8.4 ± 3.5%, the lipid volume fraction was 9.9 ± 4.7%, and the bile volume fraction was 8.2 ± 4.6%. No differences could be found between surface measurements and cross-sectional measurements. In measurements with/without the liver capsule, the differences in volume fraction were 1.63% (0.75-2.77), -0.54% (-2.97 to 0.32), and -0.15% (-1.06 to 1.24) for blood, lipid, and bile, respectively. This study shows that it is possible to manage DRS

  11. Origin of Infrared Light Modulation in Reflectance-Mode Photoplethysmography.

    Directory of Open Access Journals (Sweden)

    Igor S Sidorov

    Full Text Available We recently pointed out the important role of dermis deformation by pulsating arterial pressure in the formation of a photoplethysmographic signal at green light. The aim of this study was to explore the role of this novel finding in near-infrared (NIR light. A light-emitting diode (LED-based imaging photoplethysmography (IPPG system was used to detect spatial distribution of blood pulsations under frame-to-frame switching green and NIR illumination in the palms of 34 healthy individuals. We observed a significant increase of light-intensity modulation at the heartbeat frequency for both illuminating wavelengths after a palm was contacted with a glass plate. Strong positive correlation between data measured at green and NIR light was found, suggesting that the same signal was read independently from the depth of penetration. Analysis of the data shows that an essential part of remitted NIR light is modulated in time as a result of elastic deformations of dermis caused by variable blood pressure in the arteries. Our observations suggest that in contrast with the classical model, photoplethysmographic waveform originates from the modulation of the density of capillaries caused by the variable pressure applied to the skin from large blood vessels. Particularly, beat-to-beat transmural pressure in arteries compresses/decompresses the dermis and deforms its connective-tissue components, thus affecting the distance between the capillaries, which results in the modulation of absorption and scattering coefficients of both green and NIR light. These findings are important for the correct interpretation of this widely used medical technique, which may have novel applications in diagnosis and treatment monitoring of aging and skin diseases.

  12. Infrared and Raman spectroscopy on synthetic glasses as analogues of planetary surfaces.

    Science.gov (United States)

    Weber, Iris; Morlok, Andreas; Klemme, Stephan; Dittmer, Isabelle; Stojic, Aleksandra N.; Hiesinger, Harald; Sohn, Martin; Helbert, Jörn

    2015-04-01

    One of the fundamental aims of space mission is to understand the physical, chemical, and geologic processes and conditions of planetary formation and evolution. For this purpose, it is important to investigate analog material to correctly interpret the returned spacecraft data, including the spectral information from remote planetary surfaces. For example, mid-infrared spectroscopy provides detailed information on the mineralogical compositions of planetary surfaces via remote sensing. Data is affected by numerous factors such as grain size, illumination geometry, space weathering, and temperature. These features need to be systematically investigated on analog material in terrestrial laboratories in order to understand the mineralogy/composition of a planetary surface. In addition, Raman spectroscopy allows non-destructive analyses of planetary surfaces in the case of a landing mission. Our work at the IRIS (Infrared spectroscopy for Interplanetary Studies) laboratory at the Institut für Planetologie produces spectra for a database of the ESA/JAXA BepiColombo mission to Mercury. Onboard is a mid-infrared spectrometer (MERTIS-Mercury Radiometer and Thermal Infrared Spectrometer). This unique instrument allows us to map spectral features in the 7-14 µm range, with a spatial resolution of ~500 m [1-5]. Comparably, using our Raman spectrometer, we are continuously contributing to the Raman database for upcoming mission, e.g., the Raman Laser Spectrometer (RLS) onboard of ExoMars [6]. Material on the surface of Mercury and the other terrestrial bodies was exposed to heavy impact cratering [4]. Depending on the P/T conditions during the impact, minerals on planetary surfaces can react with the formation of glassy material. Thus, understanding the effects of impact shock and heat on the mineral structure and the resulting corresponding change in the spectral properties is of high interest for the MERTIS project. Here, we present spectral information on the first glass

  13. Quick detection and quantification of iron-cyanide complexes using fourier transform infrared spectroscopy.

    Science.gov (United States)

    Sut-Lohmann, Magdalena; Raab, Thomas

    2017-08-01

    The continuous release of persistent iron-cyanide (Fe-CN) complexes from various industrial sources poses a high hazard to the environment and indicates the necessity to analyze a considerable amount of samples. Conventional flow injection analysis (FIA) is a time and cost consuming method for cyanide (CN) determination. Thus, a rapid and economic alternative needs to be developed to quantify the Fe-CN complexes. 52 soil samples were collected at a former Manufactured Gas Plant (MGP) site in order to determine the feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS). Soil analysis revealed CN concentrations in a range from 8 to 14.809 mg kg -1 , where 97% was in the solid form (Fe 4 [Fe(CN) 6 ] 3 ), which is characterized by a single symmetrical CN band in the range 2092-2084 cm -1 . The partial least squares (PLS) calibration-validation model revealed IR response to CN tot which exceeds 2306 mg kg -1 (limit of detection, LOD). Leave-one-out cross-validation (LOO-CV) was performed on soil samples, which contained low CN tot ( 900 mg kg -1 resulted in LOD equal to 3751 mg kg -1 . It was found that FTIR spectroscopy provides the information concerning different CN species in the soil samples. Additionally, it is suitable for quantifying Fe-CN species in matrixes with CN tot  > 154 mg kg -1 . Thus, FTIR spectroscopy, in combination with the statistical approach applied here seems to be a feasible and quick method for screening of contaminated sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Total Internal Reflection Fluorescence Microscopy Imaging-Guided Confocal Single-Molecule Fluorescence Spectroscopy

    OpenAIRE

    Zheng, Desheng; Kaldaras, Leonora; Lu, H. Peter

    2013-01-01

    We have developed an integrated spectroscopy system combining total internal reflection fluorescence microscopy imaging with confocal single-molecule fluorescence spectroscopy for two-dimensional interfaces. This spectroscopy approach is capable of both multiple molecules simultaneously sampling and in situ confocal fluorescence dynamics analyses of individual molecules of interest. We have demonstrated the calibration with fluorescent microspheres, and carried out single-molecule spectroscop...

  15. New applications of near infrared spectroscopy in the food industry

    Energy Technology Data Exchange (ETDEWEB)

    Groenewald, C.A. (Peter Rassloff Instruments and Services, Norwood, South Africa)

    The near infrared spectroscopic method of analysis was initially developed for rapid analyses of protein in wheat. A brief explanation of the theory and history of near infrared spectroscopic analysis will be given. Research was done on the application of near infrared spectroscopic (NIR) in the food industry. Especially exciting was the breakthrough achieved in applying NIR to determine the dry solid content of bread. Such application could revolutionise the baking industry. Results will also be presented of research done on the application of NIR techniques for the determination of protein and fat in bread based on dry matter; hardness in wheat; absorption and sedimentation in pasta products; and use in process control in snack products manufacture. The limitations that were found in the application of NIR analysis will also be covered. The developments in NIR technology may result in these methods becoming standard practice in many food laboratories.

  16. New applications of near infrared spectroscopy in the food industry

    International Nuclear Information System (INIS)

    Groenewald, C.A.

    1984-01-01

    The near infrared spectroscopic method of analysis was initially developed for rapid analyses of protein in wheat. A brief explanation of the theory and history of near infrared spectroscopic analysis will be given. Research was done on the application of near infrared spectroscopic (NIR) in the food industry. Especially exciting was the breakthrough achieved in applying NIR to determine the dry solid content of bread. Such application could revolutionise the baking industry. Results will also be presented of research done on the application of NIR techniques for the determination of protein and fat in bread based on dry matter; hardness in wheat; absorption and sedimentation in pasta products; and use in process control in snack products manufacture. The limitations that were found in the application of NIR analysis will also be covered. The developments in NIR technology may result in these methods becoming standard practice in many food laboratories

  17. Radiofrequency/infrared double resonance spectroscopy of the HD+ ion

    International Nuclear Information System (INIS)

    Carrington, Alan; McNab, I.R.; Montgomerie, C.A.

    1989-01-01

    We describe a double resonance technique for obtaining radiofrequency spectra of the HD + ion in vibration-rotation levels close to the dissociation limit. Infrared transitions are driven by Doppler tuning an HD + ion beam into resonance with a carbon dioxide infrared laser, and are detected by measuring H + fragment ions produced by electric field dissociation of the upper vibration-rotation level. Radiofrequency transitions between nuclear hyperfine components of the lower vibration-rotation level are then detected through resonant increases in the H + fragment ion current. The high spectroscopic resolution obtained, and the ability to measure magnetic dipole hyperfine transitions, will enable the hyperfine constants to be determined accurately. (author)

  18. Thermoluminescence, infrared reflectivity and electron paramagnetic resonance properties of hemimorphite

    Energy Technology Data Exchange (ETDEWEB)

    Gallegos, E.A. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900, Sao Paulo, SP (Brazil); Cano, N.F. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900, Sao Paulo, SP (Brazil)], E-mail: nilocano@dfn.if.usp.br; Watanabe, S.; Chubaci, J.F.D. [Institute of Physics, University of Sao Paulo, Rua do Matao, Travessa R, 187, CEP 05508-900, Sao Paulo, SP (Brazil)

    2009-01-15

    Silicate mineral hemimorphite has been investigated concerning its TL, IR and EPR properties. A broad TL peak around 180 deg. C and a weaker and narrower peak around 360 deg. C were found in a sample annealed at 600 deg. C for 1 h and then irradiated. The deconvolution using the CGCD method revealed peaks around 132, 169, 222 and 367 deg. C. The reflectivity measurements showed several bands in the NIR region due to H{sub 2}O, OH and Al-OH complexes. No band was observed in the visible region. The thermal treatments were carried out from {approx}110 to 940 deg. C and dehydration was observed, first causing a diminishing optical absorption in general and the disappearance of water and hydroxyl absorption bands. The EPR spectrum of natural hemimorphite, presented Cu{sup 2+} signals at g = 2.4 and g = 2.1 plus E{sub 1}' signal superposed to Fe{sup 3+} signal around g = 2.0.

  19. Lanthanum trilactate: Vibrational spectroscopic study - infrared/Raman spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Švecová, M.; Novák, Vít; Bartůněk, V.; Člupek, M.

    2016-01-01

    Roč. 87, Nov (2016), s. 123-128 ISSN 0924-2031 Institutional support: RVO:61388963 Keywords : lanthanum trilactate * tris(2-hydroxypropanoato-O1,O2) * lanthanum tris[2-(hydroxy-kappa O)propanoato-kappa O] * Raman spectra * infrared spectra * DFT Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.740, year: 2016

  20. Applications of infrared photo-acoustic spectroscopy for wood samples

    Science.gov (United States)

    Mon-Lin Kuo; John F. McClelland; Siquan Luo; Po-Liang Chien; R.D. Walker; Chung-Yun Hse

    1988-01-01

    Various infrared (IR) spectroscopic techniques for the analysis of wood samples are briefly discussed. Theories and instrumentation of the newly developed photoacoustic spectroscopic (PAS) technique for measuring absorbance spectra of solids are presented. Some important applications of the PAS technique in wood science research are discussed. The application of the...

  1. Background and state of the art of near infrared spectroscopy in the forest sector base

    International Nuclear Information System (INIS)

    Muñiz, G.I.B. de; Magalhães, W.L.E.; Carneiro, M.E.; Viana, L.C.

    2012-01-01

    The knowledge of wood properties is the fundamental importance for the indication of the potential and use of this material. In the search for new alternatives for a fast, simple and reliable characterization, there are the non-destructive evaluations of wood. The near infrared spectroscopy (NIRS) has been used as a non-destructive method that allows qualitative and quantitative information of the constituents of biomass through the interaction of electromagnetic waves with near-infrared next to the sample. This work aims to provide a review of the technique of near infrared spectroscopy and its application in forestry. The technique is used in virtually all areas due to the level of development that this technology has reached in recent years. NIR spectroscopy has proved a quick and efficient replacement of several tests that determine the quality of the wood. This is a literature review and state of the art on the theme [pt

  2. About the use of reflectance terminology in imaging spectroscopy

    NARCIS (Netherlands)

    Schaepman-Strub, G.; Schaepman, M.E.; Dangel, S.; Painter, T.; Martonchik, J.

    2005-01-01

    Analysing databases, field and airborne spectrometer data, modelling studies and publications, a lack of consistency in the use of definitions and terminology of reflectance quantities can be observed. One example is the term `BRDF¿ (bidirectional reflectance distribution function) assigned to

  3. Chemical profiling and adulteration screening of Aquilariae Lignum Resinatum by Fourier transform infrared (FT-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy.

    Science.gov (United States)

    Qu, Lei; Chen, Jian-Bo; Zhang, Gui-Jun; Sun, Su-Qin; Zheng, Jing

    2017-03-05

    As a kind of expensive perfume and valuable herb, Aquilariae Lignum Resinatum (ALR) is often adulterated for economic motivations. In this research, Fourier transform infrared (FT-IR) spectroscopy is employed to establish a simple and quick method for the adulteration screening of ALR. First, the principal chemical constituents of ALR are characterized by FT-IR spectroscopy at room temperature and two-dimensional correlation infrared (2D-IR) spectroscopy with thermal perturbation. Besides the common cellulose and lignin compounds, a certain amount of resin is the characteristic constituent of ALR. Synchronous and asynchronous 2D-IR spectra indicate that the resin (an unstable secondary metabolite) is more sensitive than cellulose and lignin (stable structural constituents) to the thermal perturbation. Using a certified ALR sample as the reference, the infrared spectral correlation threshold is determined by 30 authentic samples and 6 adulterated samples. The spectral correlation coefficient of an authentic ALR sample to the standard reference should be not less than 0.9886 (p=0.01). Three commercial adulterated ALR samples are identified by the correlation threshold. Further interpretation of the infrared spectra of the adulterated samples indicates the common adulterating methods - counterfeiting with other kind of wood, adding ingredient such as sand to increase the weight, and adding the cheap resin such as rosin to increase the content of resin compounds. Results of this research prove that FT-IR spectroscopy can be used as a simple and accurate quality control method of ALR. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. A Multi-Wavelength Thermal Infrared and Reflectance Scene Simulation Model

    Science.gov (United States)

    Ballard, J. R., Jr.; Smith, J. A.; Smith, David E. (Technical Monitor)

    2002-01-01

    Several theoretical calculations are presented and our approach discussed for simulating overall composite scene thermal infrared exitance and canopy bidirectional reflectance of a forest canopy. Calculations are performed for selected wavelength bands of the DOE Multispectral Thermal Imagery and comparisons with atmospherically corrected MTI imagery are underway. NASA EO-1 Hyperion observations also are available and the favorable comparison of our reflective model results with these data are reported elsewhere.

  5. Fourier transform infrared spectroscopy of dental unit water line biofilm bacteria

    OpenAIRE

    Liaqat, Iram

    2009-01-01

    Fourier transform-infrared (FT-IR) spectroscopy has become an important tool for rapid analysis of complex biological samples. The infrared absorbance spectrum could be regarded as a “fingerprint” which is a feature of biochemical substances. The FT-IR spectra of fresh and stored dried samples of six bacterial isolates (Klebsiella sp., Bacillus cereus, Bacillus subtilis, Pseudomonas aeruginosa, Achromobacter xylosoxidans and Achromobacter sp.) were observed by variation in sample preparation....

  6. Chlorococcalean microalgae Ankistrodesmus convolutes biodiesel characterization with Fourier transform-infrared spectroscopy and gas chromatography mass spectroscopy techniques

    Directory of Open Access Journals (Sweden)

    Swati SONAWANE

    2015-12-01

    Full Text Available The Chlorococcalean microalgae Ankistrodesmus convolutes was found in fresh water Godawari reservoir, Ahmednagar district of Maharashtra State, India. Microalgae are modern biomass for the production of liquid biofuel due to its high solar cultivation efficiency. The collection, harvesting and drying processes were play vital role in converting algal biomass into energy liquid fuel. The oil extraction was the important step for the biodiesel synthesis. The fatty acid methyl ester (FAME synthesis was carried through base catalyzed transesterification method. The product was analyzed by using the hyphened techniques like Fourier Transform-Infrared spectroscopy (FT-IR and Gas Chromatography Mass Spectroscopy (GCMS. FT-IR Spectroscopy was results the ester as functional group of obtained product while the Gas Chromatography Mass Spectroscopy was results the six type of fatty acid methyl ester with different concentration. Ankistrodesmus convolutes biodiesel consist of 46.5% saturated and 49.14% unsaturated FAME.

  7. [Study on discrimination of varieties of fire resistive coating for steel structure based on near-infrared spectroscopy].

    Science.gov (United States)

    Xue, Gang; Song, Wen-qi; Li, Shu-chao

    2015-01-01

    In order to achieve the rapid identification of fire resistive coating for steel structure of different brands in circulating, a new method for the fast discrimination of varieties of fire resistive coating for steel structure by means of near infrared spectroscopy was proposed. The raster scanning near infrared spectroscopy instrument and near infrared diffuse reflectance spectroscopy were applied to collect the spectral curve of different brands of fire resistive coating for steel structure and the spectral data were preprocessed with standard normal variate transformation(standard normal variate transformation, SNV) and Norris second derivative. The principal component analysis (principal component analysis, PCA)was used to near infrared spectra for cluster analysis. The analysis results showed that the cumulate reliabilities of PC1 to PC5 were 99. 791%. The 3-dimentional plot was drawn with the scores of PC1, PC2 and PC3 X 10, which appeared to provide the best clustering of the varieties of fire resistive coating for steel structure. A total of 150 fire resistive coating samples were divided into calibration set and validation set randomly, the calibration set had 125 samples with 25 samples of each variety, and the validation set had 25 samples with 5 samples of each variety. According to the principal component scores of unknown samples, Mahalanobis distance values between each variety and unknown samples were calculated to realize the discrimination of different varieties. The qualitative analysis model for external verification of unknown samples is a 10% recognition ration. The results demonstrated that this identification method can be used as a rapid, accurate method to identify the classification of fire resistive coating for steel structure and provide technical reference for market regulation.

  8. Discrimination of mineral waters using near infrared spectroscopy and aquaphotomics

    Directory of Open Access Journals (Sweden)

    Munćan Jelena S.

    2014-01-01

    Full Text Available Despite that water is one of the most studied materials today its dynamic properties are still not well understood. Water state in human organism is of high importance for normal healthy functioning of human body. Different kinds of water are usually classified according to its present solutes, and concentrations of these solutes, but though it is known that water molecules can form clusters around present solutes, classification of waters based on types of water molecular organization and present clusters is not present in current literature. In this study we used multivariate analysis for classification of commercial mineral waters based on their near infrared spectra (NIR. Further, we applied Aquaphotomics, a new approach for interpretation of near infrared spectra of water, which gives insight into organization of water molecules in each of these waters.

  9. The importance of spectroscopy for infrared multiphoton excitation

    International Nuclear Information System (INIS)

    Fuss, W.; Kompa, K.L.

    1980-07-01

    It is substantiated by examples that the infrared spectra of molecules in high vibrational states are similar in width to those of the ground states. Therefore in order to explain collisionless infrared multiphoton excitation, the existence of resonance has to be checked, not only for the first three steps, but for all of them. That is, their (low resolution) spectra should be studied. This review summarizes the spectroscopic mechanisms contributing to multiphoton excitation, which have been suggested to date, including several kinds of rotational compensation and of vibrational level splitting, which cooperate to overcome the anharmonic shift. The spectral quasicontinuum, generated by intensity borrowing, must neither be very broad nor dense, and collisionless vibrational relaxation is only important at very high energies. Knowledge of relatively few spectroscopic detailes helps to understand many details and many differences in multiphoton excitatio. (orig.)

  10. Dirac charge dynamics in graphene by infrared spectroscopy

    International Nuclear Information System (INIS)

    Martin, Michael C; Li, Z.Q.; Henriksen, E.A.; Jiang, Z.; Hao, Z.; Martin, Michael C; Kim, P.; Stormer, H.L.; Basov, Dimitri N.

    2008-01-01

    A remarkable manifestation of the quantum character of electrons in matter is offered by graphene, a single atomic layer of graphite. Unlike conventional solids where electrons are described with the Schroedinger equation, electronic excitations in graphene are governed by the Dirac hamiltonian. Some of the intriguing electronic properties of graphene, such as massless Dirac quasiparticles with linear energy-momentum dispersion, have been confirmed by recent observations. Here, we report an infrared spectromicroscopy study of charge dynamics in graphene integrated in gated devices. Our measurements verify the expected characteristics of graphene and, owing to the previously unattainable accuracy of infrared experiments, also uncover significant departures of the quasiparticle dynamics from predictions made for Dirac fermions in idealized, free-standing graphene. Several observations reported here indicate the relevance of many-body interactions to the electromagnetic response of graphene

  11. THE INFRARED SPECTROSCOPY OF NEUTRAL POLYCYCLIC AROMATIC HYDROCARBON CLUSTERS

    International Nuclear Information System (INIS)

    Ricca, Alessandra; Bauschlicher, Charles W. Jr.; Allamandola, Louis J.

    2013-01-01

    The mid-infrared spectra of neutral homogeneous polycyclic aromatic hydrocarbon (PAH) clusters have been computed using density functional theory including an empirical correction for dispersion. The C-H out-of-plane bending modes are redshifted for all the clusters considered in this work. The magnitude of the redshift and the peak broadening are dependent on PAH size, shape, and on the PAH arrangement in the cluster

  12. THE INFRARED SPECTROSCOPY OF NEUTRAL POLYCYCLIC AROMATIC HYDROCARBON CLUSTERS

    Energy Technology Data Exchange (ETDEWEB)

    Ricca, Alessandra [Carl Sagan Center, SETI Institute, 189 Bernardo Avenue, Suite 100, Mountain View, CA 94043 (United States); Bauschlicher, Charles W. Jr. [Entry Systems and Technology Division, Mail Stop 230-3, NASA Ames Research Center, Moffett Field, CA 94035 (United States); Allamandola, Louis J., E-mail: Alessandra.Ricca-1@nasa.gov, E-mail: Charles.W.Bauschlicher@nasa.gov [Space Science Division, Mail Stop 245-6, NASA Ames Research Center, Moffett Field, CA 94035 (United States)

    2013-10-10

    The mid-infrared spectra of neutral homogeneous polycyclic aromatic hydrocarbon (PAH) clusters have been computed using density functional theory including an empirical correction for dispersion. The C-H out-of-plane bending modes are redshifted for all the clusters considered in this work. The magnitude of the redshift and the peak broadening are dependent on PAH size, shape, and on the PAH arrangement in the cluster.

  13. Polyisobutenylsuccinimides as detergents and dispersants in fuel: infrared spectroscopy application

    Energy Technology Data Exchange (ETDEWEB)

    Aleman-Vazquez, L.O.; Villagomez-Ibarra, J.R. [Instituto Mexicano del Petrole, San Bartolo Atepehuacan (Mexico). Gerencia de Productos Quimicos

    2001-05-01

    Polyalkenylsuccinimides were synthesized and their dispersancy properties evaluated in an internal combustion engine. The synthesis is based on the reaction of polyisobutene with maleic anhydride as the first step. The polyisobutenylsuccinic anhydride obtained reacts with primary amines in the last step to give polyalkenylsuccinimides. The results of the evaluations showed that some polyisobutenylsuccinimides reduce the deposit formation in the intake system with good efficiency. Infrared spectra of the prepared compounds allowed their identification. 16 refs., 2 tabs.

  14. Construction of Models for Nondestructive Prediction of Ingredient Contents in Blueberries by Near-infrared Spectroscopy Based on HPLC Measurements.

    Science.gov (United States)

    Bai, Wenming; Yoshimura, Norio; Takayanagi, Masao; Che, Jingai; Horiuchi, Naomi; Ogiwara, Isao

    2016-06-28

    Nondestructive prediction of ingredient contents of farm products is useful to ship and sell the products with guaranteed qualities. Here, near-infrared spectroscopy is used to predict nondestructively total sugar, total organic acid, and total anthocyanin content in each blueberry. The technique is expected to enable the selection of only delicious blueberries from all harvested ones. The near-infrared absorption spectra of blueberries are measured with the diffuse reflectance mode at the positions not on the calyx. The ingredient contents of a blueberry determined by high-performance liquid chromatography are used to construct models to predict the ingredient contents from observed spectra. Partial least squares regression is used for the construction of the models. It is necessary to properly select the pretreatments for the observed spectra and the wavelength regions of the spectra used for analyses. Validations are necessary for the constructed models to confirm that the ingredient contents are predicted with practical accuracies. Here we present a protocol to construct and validate the models for nondestructive prediction of ingredient contents in blueberries by near-infrared spectroscopy.

  15. Infrared Multiple Photon Dissociation Spectroscopy Of Metal Cluster-Adducts

    Science.gov (United States)

    Cox, D. M.; Kaldor, A.; Zakin, M. R.

    1987-01-01

    Recent development of the laser vaporization technique combined with mass-selective detection has made possible new studies of the fundamental chemical and physical properties of unsupported transition metal clusters as a function of the number of constituent atoms. A variety of experimental techniques have been developed in our laboratory to measure ionization threshold energies, magnetic moments, and gas phase reactivity of clusters. However, studies have so far been unable to determine the cluster structure or the chemical state of chemisorbed species on gas phase clusters. The application of infrared multiple photon dissociation IRMPD to obtain the IR absorption properties of metal cluster-adsorbate species in a molecular beam is described here. Specifically using a high power, pulsed CO2 laser as the infrared source, the IRMPD spectrum for methanol chemisorbed on small iron clusters is measured as a function of the number of both iron atoms and methanols in the complex for different methanol isotopes. Both the feasibility and potential utility of IRMPD for characterizing metal cluster-adsorbate interactions are demonstrated. The method is generally applicable to any cluster or cluster-adsorbate system dependent only upon the availability of appropriate high power infrared sources.

  16. Infrared photon-echo spectroscopy of water : The thermalization effects

    NARCIS (Netherlands)

    Pshenichnikov, Maxim S.; Yeremenko, Sergey; Wiersma, Douwe A.; Kobayashi, Takayoshi; Kobayashi, Tetsuro; Nelson, Keith A.; Okada, Tadashi; Silvestri, Sandro De

    2005-01-01

    The larger part of the nonlinear response in IR photon-echo and transient-grating spectroscopy on HDO-D2O mixtures at > 1-ps delays is found to originate from the D2O refractive index modulation due to local volume thermalization.

  17. Diagnosis with near infrared spectroscopy during minimally invasive procedures

    NARCIS (Netherlands)

    R. Nachabé (Rami)

    2012-01-01

    textabstractThe goal of this dissertation is to present the potential of diffuse optical spectroscopy technique to characterize and differentiate types of tissue, including dysplastic and cancerous tissues, when measuring the tissue spectra during a surgical or an interventional procedure under

  18. High resolution mid-infrared spectroscopy based on frequency upconversion

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Hu, Qi; Tidemand-Lichtenberg, Peter

    2013-01-01

    signals can be analyzed. The obtainable frequency resolution is usually in the nm range where sub nm resolution is preferred in many applications, like gas spectroscopy. In this work we demonstrate how to obtain sub nm resolution when using upconversion. In the presented realization one object point...... high resolution spectral performance by observing emission from hot water vapor in a butane gas burner....

  19. Discrimination between Bacillus and Alicyclobacillus isolates in apple juice by Fourier transform infrared spectroscopy and multivariate analysis.

    Science.gov (United States)

    Al-Holy, Murad A; Lin, Mengshi; Alhaj, Omar A; Abu-Goush, Mahmoud H

    2015-02-01

    Alicyclobacillus is a causative agent of spoilage in pasteurized and heat-treated apple juice products. Differentiating between this genus and the closely related Bacillus is crucially important. In this study, Fourier transform infrared spectroscopy (FT-IR) was used to identify and discriminate between 4 Alicyclobacillus strains and 4 Bacillus isolates inoculated individually into apple juice. Loading plots over the range of 1350 and 1700 cm(-1) reflected the most distinctive biochemical features of Bacillus and Alicyclobacillus. Multivariate statistical methods (for example, principal component analysis and soft independent modeling of class analogy) were used to analyze the spectral data. Distinctive separation of spectral samples was observed. This study demonstrates that FT-IR spectroscopy in combination with multivariate analysis could serve as a rapid and effective tool for fruit juice industry to differentiate between Bacillus and Alicyclobacillus and to distinguish between species belonging to these 2 genera. © 2015 Institute of Food Technologists®

  20. Physico-chemical characterization of products from vacuum oil under delayed coking process by infrared spectroscopy and chemometrics methods

    International Nuclear Information System (INIS)

    Meléndez, L V; Cabanzo, R; Mejía-Ospino, E; Guzmán, A

    2016-01-01

    Eight vacuum residues and their delayed coking liquids products from Colombian crude were study by infrared spectroscopy with attenuated total reflectance (FTIR-ATR) and principal component analysis (PCA). For the samples the structural parameters of aromaticity factor (fa), alifaticity (A2500-3100cm -1 ), aromatic condensation degree (GCA), length of aliphatic chains (LCA) and aliphatic chain length associated with aromatic (LACAR) were determined through the development of a methodology, which includes the previous processing of spectroscopy data, identifying the regions in the IR spectra of greatest variance using PCA and molecules patterns. The parameters were compared with the results obtained from proton magnetic resonance ( 1 H-NMR) and 13 C-NMR. The results showed the influence and correlation of structural parameters with some physicochemical properties such as API gravity, weight percent sulphur (% S) and Conradson carbon content (% CCR) (paper)