WorldWideScience

Sample records for infrared spectroscopy rairs

  1. 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.

  2. 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.

  3. 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.

  4. 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...

  5. 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.)

  6. Synchrotron far-IR RAIRS studies of interfaces created by polyfunctional organic molecules at defined metal surfaces

    International Nuclear Information System (INIS)

    Raval, R.; Williams, J.; Roberts, A.J.; Nunney, T.S.; Surman, M.

    1998-01-01

    Far-IR Reflection Absorption Infrared Spectroscopy (RAIRS) has been used to probe sub monolayers and multilayers of polyfunctional organic ad layers deposited under clean controlled conditions on small-area single-crystal surfaces, using the newly commissioned Daresbury 13.3 far-IR synchrotron beamline. It's shown that the current performance of the beamline allows to monitor fractions of monolayers of formate species on Cu(110), formed at 300 K from the deprotonation of formic acid. Two distinct vCu-O vibrations are observed for coverages up to 0.25 monolayer. The paper attributes the two bands to at least two chemically distinct species, each possessing a local site symmetry of C 2v and bonded to the metal surface via the two oxygen atoms. The two types of formate species are thought to arise from local density fluctuations in formate coverage across the ad layer which leads to local changes in the Cu-O bond. In additions, it's reported far-IR RAIRS spectra of bio molecule/metal interfaces created by depositing thin films (3-10 layers) of the chiral amino-acid, L-methionine, on Cu(110) at 300 K. The multilayer spectra closely resemble the far-IR spectra obtained from crystalline L-methionine, suggesting that the thin layer consists of the zwitterionic species. These thin bio films are stable on the surface to >330 K. No growth of metal-ligand vibrations in the multilayer phase is observed, demonstrating that corrosive chemisorption processes that create Cu-methionine complexes in the multilayer by leaching of surface Cu atoms do not occur in these conditions

  7. 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...

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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.)

  13. 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)

  14. 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.

  15. Du texte littéraire à la lecture littéraire : les enjeux d'un déplacement en classe de FLE/S

    OpenAIRE

    Collès, Luc; Dufays, Jean-Louis

    2007-01-01

    L’article analyse les moyens et les enjeux de deux approches complémentaires de la littérature en classe de FLE/S. Dans un premier temps, la lecture des textes littéraires est envisagée dans une approche pragmatique, qui vise à faire passer les apprenants du discours usuel au discours littéraire dans un même geste. Cette approche est elle-même intégrée dans la perspective actionnelle définie par le Cadre européen commun de référence pour les langues (2001), dont l’objectif est la formation d’...

  16. De la philosophie des concours littéraires au Burkina Faso | Sanou ...

    African Journals Online (AJOL)

    Au Burkina Faso, c'est l'Etat, à travers l'administration culturelle, qui s'est substitué aux initiatives privées, individuelles et/ou collectives par sa participation à la mise en place du champ littéraire. Sa politique s'est essentiellement concentrée sur les concours littéraires dont la philosophie est guidée par l'encouragement des ...

  17. 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.

  18. 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)

  19. 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.

  20. 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.)

  1. Versatile silicon-waveguide supercontinuum for coherent mid-infrared spectroscopy

    Science.gov (United States)

    Nader, Nima; Maser, Daniel L.; Cruz, Flavio C.; Kowligy, Abijith; Timmers, Henry; Chiles, Jeff; Fredrick, Connor; Westly, Daron A.; Nam, Sae Woo; Mirin, Richard P.; Shainline, Jeffrey M.; Diddams, Scott

    2018-03-01

    Laser frequency combs, with their unique combination of precisely defined spectral lines and broad bandwidth, are a powerful tool for basic and applied spectroscopy. Here, we report offset-free, mid-infrared frequency combs and dual-comb spectroscopy through supercontinuum generation in silicon-on-sapphire waveguides. We leverage robust fabrication and geometrical dispersion engineering of nanophotonic waveguides for multi-band, coherent frequency combs spanning 70 THz in the mid-infrared (2.5 μm-6.2 μm). Precise waveguide fabrication provides significant spectral broadening with engineered spectra targeted at specific mid-infrared bands. We characterize the relative-intensity-noise of different bands and show that the measured levels do not pose any limitation for spectroscopy applications. Additionally, we use the fabricated photonic devices to demonstrate dual-comb spectroscopy of a carbonyl sulfide gas sample at 5 μm. This work forms the technological basis for applications such as point sensors for fundamental spectroscopy, atmospheric chemistry, trace and hazardous gas detection, and biological microscopy.

  2. Versatile silicon-waveguide supercontinuum for coherent mid-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Nima Nader

    2018-03-01

    Full Text Available Laser frequency combs, with their unique combination of precisely defined spectral lines and broad bandwidth, are a powerful tool for basic and applied spectroscopy. Here, we report offset-free, mid-infrared frequency combs and dual-comb spectroscopy through supercontinuum generation in silicon-on-sapphire waveguides. We leverage robust fabrication and geometrical dispersion engineering of nanophotonic waveguides for multi-band, coherent frequency combs spanning 70 THz in the mid-infrared (2.5 μm–6.2 μm. Precise waveguide fabrication provides significant spectral broadening with engineered spectra targeted at specific mid-infrared bands. We characterize the relative-intensity-noise of different bands and show that the measured levels do not pose any limitation for spectroscopy applications. Additionally, we use the fabricated photonic devices to demonstrate dual-comb spectroscopy of a carbonyl sulfide gas sample at 5 μm. This work forms the technological basis for applications such as point sensors for fundamental spectroscopy, atmospheric chemistry, trace and hazardous gas detection, and biological microscopy.

  3. 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)

  4. 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...

  5. 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...

  6. Le Téméraire des Allemands : la perception de Charles le Téméraire dans l’espace allemand au XVe siècle

    OpenAIRE

    Dubray, Julien

    2017-01-01

    Nous chercherons dans ce travail à étudier la perception de Charles le Téméraire dans l’Empire à la fin du XV e siècle. Notre enquête se limitera aux régions de langue allemande. Pour ce faire, nous emploierons des sources diplomatiques, ainsi que des sources littéraires, tels que les poèmes et les lieder qui circulèrent du vivant du duc. Notre source principale consistera cependant en un corpus de chroniques réalisées entre la mort de Charles en 1477 et les premières années du XVI e siècle e...

  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. 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)

  9. 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

  10. 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.

  11. 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.

  12. 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...

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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)

  19. 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…

  20. Vers une sociologie économique des singularités littéraires

    Directory of Open Access Journals (Sweden)

    Anthony Glinoer

    2010-01-01

    Full Text Available Passé relativement inaperçu en sociologie de l’art et en sociologie de la littérature mais amplement discuté par des sociologues et des économistes, voici un livre qui pourrait grandement contribuer à un renouvellement de la pensée sociologique sur le littéraire, voire à un salutaire changement de perspective.  La sociologie de la littérature ― et tout particulièrement les travaux inspirés par la théorie du champ littéraire de Pierre Bourdieu ― s’est en effet largement consacrée à la question...

  1. 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.)

  2. 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.

  3. 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.

  4. 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).

  5. 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.

  6. 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.

  7. 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...

  8. 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...

  9. 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.

  10. 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...

  11. 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.

  12. 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...

  13. 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.

  14. [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.

  15. 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.

  16. Num\\'{e}raire-invariant preferences in financial modeling

    OpenAIRE

    Kardaras, Constantinos

    2009-01-01

    We provide an axiomatic foundation for the representation of num\\'{e}raire-invariant preferences of economic agents acting in a financial market. In a static environment, the simple axioms turn out to be equivalent to the following choice rule: the agent prefers one outcome over another if and only if the expected (under the agent's subjective probability) relative rate of return of the latter outcome with respect to the former is nonpositive. With the addition of a transitivity requirement, ...

  17. 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.

  18. 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.

  19. 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

  20. 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 ...

  1. 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.

  2. 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.

  3. Study on Angelica and its different extracts by Fourier transform infrared spectroscopy and two-dimensional correlation IR spectroscopy

    Science.gov (United States)

    Liu, Hong-xia; Sun, Su-qin; Lv, Guang-hua; Chan, Kelvin K. C.

    2006-05-01

    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 correlation infrared spectroscopy (2D-IR) to study the main constituents in traditional Chinese medicine Angelica and its different extracts (extracted by petroleum ether, ethanol and water in turn). The findings indicated that FT-IR spectrum can provide many holistic variation rules of chemical constituents. Use of the macroscopical fingerprint characters of FT-IR and 2D-IR spectrum can not only identify the main chemical constituents in medicinal materials and their different extracts, but also compare the components differences among the similar samples. This analytical method is highly rapid, effective, visual and accurate for pharmaceutical research.

  4. 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.

  5. Reactions of ethanol on Ru

    NARCIS (Netherlands)

    Sturm, Jacobus Marinus; Liu, Feng; Lee, Christopher James; Bijkerk, Frederik

    2012-01-01

    The adsorption and reactions of ethanol on Ru(0001) were studied with temperatureprogrammed desorption (TPD) and reflection-absorption infrared spectroscopy (RAIRS). Ethanol was found to adsorb intact onto Ru(0001) below 100 K. Heating to 250 K resulted in formation of ethoxy groups, which undergo

  6. 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.

  7. 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).

  8. 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,

  9. Near-infrared spectroscopy can reveal increases in brain activity related to animal-assisted therapy.

    Science.gov (United States)

    Morita, Yuka; Ebara, Fumio; Morita, Yoshimitsu; Horikawa, Etsuo

    2017-08-01

    [Purpose] Previous studies have indicated that animal-assisted therapy can promote recovery of psychological, social, and physiological function in mental disorders. This study was designed as a pilot evaluation of the use of near-infrared spectroscopy to objectively identify changes in brain activity that could mediate the effect of animal-assisted therapy. [Subjects and Methods] The participants were 20 healthy students (10 males and 10 females; age 19-21 years) of the Faculty of Agriculture, Saga University. Participants were shown a picture of a Tokara goat or shack (control) while prefrontal cortical oxygenated haemoglobin levels (representing neural activity) were measured by near-infrared spectroscopy. [Results] The prefrontal cortical near-infrared spectroscopy signal was significantly higher during viewing of the animal picture than during a rest condition or during viewing of the control picture. [Conclusion] Our results suggest that near-infrared spectroscopy can be used to objectively identify brain activity changes during human mentation regarding animals; furthermore, these preliminary results suggest the efficacy of animal-assisted therapy could be related to increased activation of the prefrontal cortex.

  10. 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...

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. [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

  16. A Cross-Sectional Survey of Near-Infrared Spectroscopy Use in Pediatric Cardiac ICUs in the United Kingdom, Ireland, Italy, and Germany.

    Science.gov (United States)

    Hoskote, Aparna U; Tume, Lyvonne N; Trieschmann, Uwe; Menzel, Christoph; Cogo, Paola; Brown, Katherine L; Broadhead, Michael W

    2016-01-01

    Despite the increasing use of near-infrared spectroscopy across pediatric cardiac ICUs, there is significant variability and equipoise with no universally accepted management algorithms. We aimed to explore the use of near-infrared spectroscopy in pediatric cardiac ICUs in the United Kingdom, Ireland, Italy, and Germany. A cross-sectional multicenter, multinational electronic survey of one consultant in each pediatric cardiac ICU. Pediatric cardiac ICUs in the United Kingdom and Ireland (n = 13), Italy (n = 12), and Germany (n = 33). Questionnaire targeted to establish use, targets, protocols/thresholds for intervention, and perceived usefulness of near-infrared spectroscopy monitoring. Overall, 42 of 58 pediatric cardiac ICUs (72%) responded: United Kingdom and Ireland, 11 of 13 (84.6%); Italy, 12 of 12 (100%); and Germany, 19 of 33 (57%, included all major centers). Near-infrared spectroscopy usage varied with 35% (15/42) reporting that near-infrared spectroscopy was not used at all (7/42) or occasionally (8/42); near-infrared spectroscopy use was much less common in the United Kingdom (46%) when compared with 78% in Germany and all (100%) in Italy. Only four units had a near-infrared spectroscopy protocol, and 18 specifically used near-infrared spectroscopy in high-risk patients; 37 respondents believed that near-infrared spectroscopy added value to standard monitoring and 23 believed that it gave an earlier indication of deterioration, but only 19 would respond based on near-infrared spectroscopy data alone. Targets for absolute values and critical thresholds for intervention varied widely between units. The reasons cited for not or occasionally using near-infrared spectroscopy were expense (n = 6), limited evidence and uncertainty on how it guides management (n = 4), difficulty in interpretation, and unreliability of data (n = 3). Amongst the regular or occasional near-infrared spectroscopy users (n = 35), 28 (66%) agreed that a multicenter study is warranted

  17. 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

  18. Far-infrared spectroscopy of lanthanide-based molecular magnetic materials

    Energy Technology Data Exchange (ETDEWEB)

    Haas, Sabrina

    2015-05-13

    This thesis demonstrates the applicability of far-infrared spectroscopy for the study of the crystal-field splitting of lanthanides in single-molecular magnetic materials. The far-infrared studies of three different kinds of single-molecular-magnetic materials, a single-ion magnet, a single-chain magnet and an exchange-coupled cluster, yielded a deeper understanding of the crystal-field splitting of the lanthanides in these materials. In addition, our results offered the opportunity to gain a deeper insight into the relaxation processes of these materials.

  19. 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....

  20. 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.

  1. 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.

  2. 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...

  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. High-coherence mid-infrared dual-comb spectroscopy spanning 2.6 to 5.2 μm

    Science.gov (United States)

    Ycas, Gabriel; Giorgetta, Fabrizio R.; Baumann, Esther; Coddington, Ian; Herman, Daniel; Diddams, Scott A.; Newbury, Nathan R.

    2018-04-01

    Mid-infrared dual-comb spectroscopy has the potential to supplant conventional Fourier-transform spectroscopy in applications requiring high resolution, accuracy, signal-to-noise ratio and speed. Until now, mid-infrared dual-comb spectroscopy has been limited to narrow optical bandwidths or low signal-to-noise ratios. Using digital signal processing and broadband frequency conversion in waveguides, we demonstrate a mid-infrared dual-comb spectrometer covering 2.6 to 5.2 µm with comb-tooth resolution, sub-MHz frequency precision and accuracy, and a spectral signal-to-noise ratio as high as 6,500. As a demonstration, we measure the highly structured, broadband cross-section of propane from 2,840 to 3,040 cm-1, the complex phase/amplitude spectra of carbonyl sulfide from 2,000 to 2,100 cm-1, and of a methane, acetylene and ethane mixture from 2,860 to 3,400 cm-1. The combination of broad bandwidth, comb-mode resolution and high brightness will enable accurate mid-infrared spectroscopy in precision laboratory experiments and non-laboratory applications including open-path atmospheric gas sensing, process monitoring and combustion.

  5. 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...

  6. 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

  7. 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...

  8. On-Line Monitoring of Fermentation Processes by Near Infrared and Fluorescence Spectroscopy

    DEFF Research Database (Denmark)

    Svendsen, Carina

    Monitoring and control of fermentation processes is important to ensure high product yield, product quality and product consistency. More knowledge on on-line analytical techniques such as near infrared and fluorescence spectroscopy is desired in the fermentation industry to increase the efficiency...... of on-line monitoring systems. The primary aim of this thesis is to elucidate and explore the dynamics in fermentation processes by spectroscopy. Though a number of successful on-line lab-scale monitoring systems have been reported, it seems that several challenges are still met, which limits the number...... of full-scale systems implemented in industrial fermentation processes. This thesis seeks to achieve a better understanding of the techniques near infrared and fluorescence spectroscopy and thereby to solve some of the challenges that are encountered. The thesis shows the advantages of applying real...

  9. Renal geology (quantitative renal stone analysis) by 'Fourier transform infrared spectroscopy'.

    Science.gov (United States)

    Singh, Iqbal

    2008-01-01

    To prospectively determine the precise stone composition (quantitative analysis) by using infrared spectroscopy in patients with urinary stone disease presenting to our clinic. To determine an ideal method for stone analysis suitable for use in a clinical setting. After routine and a detailed metabolic workup of all patients of urolithiasis, stone samples of 50 patients of urolithiasis satisfying the entry criteria were subjected to the Fourier transform infrared spectroscopic analysis after adequate sample homogenization at a single testing center. Calcium oxalate monohydrate and dihydrate stone mixture was most commonly encountered in 35 (71%) followed by calcium phosphate, carbonate apatite, magnesium ammonium hexahydrate and xanthine stones. Fourier transform infrared spectroscopy allows an accurate, reliable quantitative method of stone analysis. It also helps in maintaining a computerized large reference library. Knowledge of precise stone composition may allow the institution of appropriate prophylactic therapy despite the absence of any detectable metabolic abnormalities. This may prevent and or delay stone recurrence.

  10. Is numérairology the future of monetary economics?: unbundling numéraire and medium of exchange through a virtual currency and a shadow exchange rate

    OpenAIRE

    Willem H. Buiter

    2007-01-01

    The paper discusses some fundamental problems in monetary economics associated with the determination and role of the numéraire. The issues are introduced by formalising a proposal, attributed to Eisler, to remove the zero lower bound on nominal interest rates by unbundling the numéraire and medium of exchange/means of payment functions of money. The monetary authorities manage the exchange rate between the numéraire ('sterling') and the means of payment ('drachma'). The short nominal interes...

  11. 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.

  12. Mid-infrared Spectroscopy/Bioimaging: Moving toward MIR optical biopsy

    DEFF Research Database (Denmark)

    Seddon, Angela B.; Napier, Bruce; Lindsay, Ian

    2016-01-01

    ), with its ability to enable in vivo medical diagnosis, is particularly interesting. In fact, the European Commission provides support for a major effort to develop the technology through its Framework Seven (FP7) project called MINERVA (MId- to-NEaR- infrared spectroscopy for improVed medical diAgnostics)....

  13. Mid-infrared, long wave infrared (4-12 μm) molecular emission signatures from pharmaceuticals using laser-induced breakdown spectroscopy (LIBS).

    Science.gov (United States)

    Yang, Clayton S-C; Brown, Ei E; Kumi-Barimah, Eric; Hommerich, Uwe H; Jin, Feng; Trivedi, Sudhir B; Samuels, Alan C; Snyder, A Peter

    2014-01-01

    In an effort to augment the atomic emission spectra of conventional laser-induced breakdown spectroscopy (LIBS) and to provide an increase in selectivity, mid-wave to long-wave infrared (IR), LIBS studies were performed on several organic pharmaceuticals. Laser-induced breakdown spectroscopy signature molecular emissions of target organic compounds are observed for the first time in the IR fingerprint spectral region between 4-12 μm. The IR emission spectra of select organic pharmaceuticals closely correlate with their respective standard Fourier transform infrared spectra. Intact and/or fragment sample molecular species evidently survive the LIBS event. The combination of atomic emission signatures derived from conventional ultraviolet-visible-near-infrared LIBS with fingerprints of intact molecular entities determined from IR LIBS promises to be a powerful tool for chemical detection.

  14. Advances in Contactless Silicon Defect and Impurity Diagnostics Based on Lifetime Spectroscopy and Infrared Imaging

    Directory of Open Access Journals (Sweden)

    Jan Schmidt

    2007-01-01

    Full Text Available This paper gives a review of some recent developments in the field of contactless silicon wafer characterization techniques based on lifetime spectroscopy and infrared imaging. In the first part of the contribution, we outline the status of different lifetime spectroscopy approaches suitable for the identification of impurities in silicon and discuss—in more detail—the technique of temperature- and injection-dependent lifetime spectroscopy. The second part of the paper focuses on the application of infrared cameras to analyze spatial inhomogeneities in silicon wafers. By measuring the infrared signal absorbed or emitted from light-generated free excess carriers, high-resolution recombination lifetime mappings can be generated within seconds to minutes. In addition, mappings of non-recombination-active trapping centers can be deduced from injection-dependent infrared lifetime images. The trap density has been demonstrated to be an important additional parameter in the characterization and assessment of solar-grade multicrystalline silicon wafers, as areas of increased trap density tend to deteriorate during solar cell processing.

  15. 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).

  16. Gasoline classification using near infrared (NIR) spectroscopy data: Comparison of multivariate techniques

    Energy Technology Data Exchange (ETDEWEB)

    Balabin, Roman M., E-mail: balabin@org.chem.ethz.ch [Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich (Switzerland); Safieva, Ravilya Z. [Gubkin Russian State University of Oil and Gas, 119991 Moscow (Russian Federation); Lomakina, Ekaterina I. [Faculty of Computational Mathematics and Cybernetics, Lomonosov Moscow State University, 119992 Moscow (Russian Federation)

    2010-06-25

    Near infrared (NIR) spectroscopy is a non-destructive (vibrational spectroscopy based) measurement technique for many multicomponent chemical systems, including products of petroleum (crude oil) refining and petrochemicals, food products (tea, fruits, e.g., apples, milk, wine, spirits, meat, bread, cheese, etc.), pharmaceuticals (drugs, tablets, bioreactor monitoring, etc.), and combustion products. In this paper we have compared the abilities of nine different multivariate classification methods: linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), regularized discriminant analysis (RDA), soft independent modeling of class analogy (SIMCA), partial least squares (PLS) classification, K-nearest neighbor (KNN), support vector machines (SVM), probabilistic neural network (PNN), and multilayer perceptron (ANN-MLP) - for gasoline classification. Three sets of near infrared (NIR) spectra (450, 415, and 345 spectra) were used for classification of gasolines into 3, 6, and 3 classes, respectively, according to their source (refinery or process) and type. The 14,000-8000 cm{sup -1} NIR spectral region was chosen. In all cases NIR spectroscopy was found to be effective for gasoline classification purposes, when compared with nuclear magnetic resonance (NMR) spectroscopy or gas chromatography (GC). KNN, SVM, and PNN techniques for classification were found to be among the most effective ones. Artificial neural network (ANN-MLP) approach based on principal component analysis (PCA), which was believed to be efficient, has shown much worse results. We hope that the results obtained in this study will help both further chemometric (multivariate data analysis) investigations and investigations in the sphere of applied vibrational (infrared/IR, near-IR, and Raman) spectroscopy of sophisticated multicomponent systems.

  17. Gasoline classification using near infrared (NIR) spectroscopy data: Comparison of multivariate techniques

    International Nuclear Information System (INIS)

    Balabin, Roman M.; Safieva, Ravilya Z.; Lomakina, Ekaterina I.

    2010-01-01

    Near infrared (NIR) spectroscopy is a non-destructive (vibrational spectroscopy based) measurement technique for many multicomponent chemical systems, including products of petroleum (crude oil) refining and petrochemicals, food products (tea, fruits, e.g., apples, milk, wine, spirits, meat, bread, cheese, etc.), pharmaceuticals (drugs, tablets, bioreactor monitoring, etc.), and combustion products. In this paper we have compared the abilities of nine different multivariate classification methods: linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), regularized discriminant analysis (RDA), soft independent modeling of class analogy (SIMCA), partial least squares (PLS) classification, K-nearest neighbor (KNN), support vector machines (SVM), probabilistic neural network (PNN), and multilayer perceptron (ANN-MLP) - for gasoline classification. Three sets of near infrared (NIR) spectra (450, 415, and 345 spectra) were used for classification of gasolines into 3, 6, and 3 classes, respectively, according to their source (refinery or process) and type. The 14,000-8000 cm -1 NIR spectral region was chosen. In all cases NIR spectroscopy was found to be effective for gasoline classification purposes, when compared with nuclear magnetic resonance (NMR) spectroscopy or gas chromatography (GC). KNN, SVM, and PNN techniques for classification were found to be among the most effective ones. Artificial neural network (ANN-MLP) approach based on principal component analysis (PCA), which was believed to be efficient, has shown much worse results. We hope that the results obtained in this study will help both further chemometric (multivariate data analysis) investigations and investigations in the sphere of applied vibrational (infrared/IR, near-IR, and Raman) spectroscopy of sophisticated multicomponent systems.

  18. 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.

  19. 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.

  20. Juan Goytisolo: Le soi, le monde et la création littéraire

    Directory of Open Access Journals (Sweden)

    Pablo Romero Alegría

    2010-01-01

    Full Text Available Reseña de la obra: Yannick Llored. Le soi, le monde et la création littéraire. Presses Universitaires du Septentrion. Villeneuve d’Ascq (Francia. 2009. 421 págs. ISBN: 978-2-75740-0089-0

  1. 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....

  2. 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.

  3. 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

  4. 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.

  5. PARTICULATE MATTER MEASUREMENTS USING OPEN-PATH FOURIER TRANSFORM INFRARED SPECTROSCOPY

    Science.gov (United States)

    Open-path Fourier transform infrared (OP-FT1R) spectroscopy is an accepted technology for measuring gaseous air contaminants. OP-FT1R absorbance spectra acquired during changing aerosols conditions reveal related changes in very broad baseline features. Usually, this shearing of ...

  6. Noncontact blood species identification method based on spatially resolved near-infrared transmission spectroscopy

    Science.gov (United States)

    Zhang, Linna; Sun, Meixiu; Wang, Zhennan; Li, Hongxiao; Li, Yingxin; Li, Gang; Lin, Ling

    2017-09-01

    The inspection and identification of whole blood are crucially significant for import-export ports and inspection and quarantine departments. In our previous research, we proved Near-Infrared diffuse transmitted spectroscopy method was potential for noninvasively identifying three blood species, including macaque, human and mouse, with samples measured in the cuvettes. However, in open sampling cases, inspectors may be endangered by virulence factors in blood samples. In this paper, we explored the noncontact measurement for classification, with blood samples measured in the vacuum blood vessels. Spatially resolved near-infrared spectroscopy was used to improve the prediction accuracy. Results showed that the prediction accuracy of the model built with nine detection points was more than 90% in identification between all five species, including chicken, goat, macaque, pig and rat, far better than the performance of the model built with single-point spectra. The results fully supported the idea that spatially resolved near-infrared spectroscopy method can improve the prediction ability, and demonstrated the feasibility of this method for noncontact blood species identification in practical applications.

  7. 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 ...

  8. Discrimination of wild-growing and cultivated Lentinus edodes by tri-step infrared spectroscopy

    Science.gov (United States)

    Lin, Haojian; Liu, Gang; Yang, Weimei; An, Ran; Ou, Quanhong

    2018-01-01

    It's not easy to discriminate dried wild-growing Lentinus edodes (WL) and cultivated Lentinus edodes (CL) by conventional method based on the morphological inspection of fruiting bodies. In this paper, fruiting body samples of WL and CL are discriminated by a tri-step IR spectroscopy method, including Fourier transform infrared (FT-IR) spectroscopy, second derivatives infrared (SD-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy under thermal perturbation. The results show that the FT-IR spectra of WL and CL are similar in holistic spectral profile. More significant differences are exhibited in their SD-IR spectra in the range of 1700 - 900 cm-1. Furthermore, more evident differences have been observed in their synchronous 2D-IR spectra in the range of 2970 - 2900, 1678 - 1390, 1250 -1104 and 1090 - 1030 cm-1. The CL has thirteen auto-peaks at 2958, 2921, 1649, 1563, 1450, 1218, 1192, 1161, 1140, 1110, 1082, 1065 and 1047 cm-1, in which the four strongest auto-peaks are at 2921, 1563, 1192 and 1082 cm-1. The WL shows fifteen auto-peaks at 2960, 2937, 2921, 1650, 1615, 1555, 1458, 1219, 1190, 1138, 1111, 1084, 1068, 1048 and 1033 cm-1, in which the four strongest auto-peaks are at 2921, 1650, 1190 and 1068 cm-1. This study shows the potential of FT-IR spectroscopy and 2D correlation analysis in a simple and quick distinction of wild-growing and cultivated mushrooms.

  9. Application of near-infrared spectroscopy to preservative-treated wood

    Science.gov (United States)

    Chi-Leung So; Stan T. Lebow; Thomas L. Eberhardt; Leslie H. Groom; Todd F. Shupe

    2009-01-01

    Near infrared (NIR) spectroscopy is now a widely-used technique in the field of forest products, especially for physical and mechanical property determinations. This technique is also ideal for the chemical analysis of wood. There has been a growing need to find a rapid, inexpensive and reliable method to distinguish between preservative-treated and untreated waste...

  10. 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

  11. Le bovarysme, histoire et interprétation d’une pathologie littéraire à l’âge moderne

    Directory of Open Access Journals (Sweden)

    Delphine Jayot

    2009-02-01

    Full Text Available Originellement hybride, la notion de bovarysme, inventée à la fin du XIXe siècle par Jules de Gaultier, a été conçue à partir d’un personnage littéraire pour décrire un phénomène de psychologie normale ou pathologique. Creuset d’interrogations pour deux champs de savoir distincts, la littérature et la psychopathologie, elle va connaître un double destin en devenant, au XXe siècle, une notion clé de la critique littéraire comme de la psychiatrie. Au croisement de diverses disciplines, cette no...

  12. Evaluation of portable near-infrared spectroscopy for organic milk authentication

    NARCIS (Netherlands)

    Liu, Ningjing; Parra, Hector Aya; Pustjens, Annemieke; Hettinga, Kasper; Mongondry, Philippe; Ruth, van Saskia M.

    2018-01-01

    Organic products are vulnerable to fraud due to their premium price. Analytical methodology helps to manage the risk of fraud and due to the miniaturization of equipment, tests may nowadays even be rapidly applied on-site. The current study aimed to evaluate portable near infrared spectroscopy

  13. 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.

  14. 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.

  15. 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

  16. Is near-infrared spectroscopy clinically useful in the preterm infant?

    DEFF Research Database (Denmark)

    da Costa, Cristine Sortica; Greisen, Gorm; Austin, Topun

    2015-01-01

    Near-infrared spectroscopy (NIRS) has been used to study cerebral haemodynamics and oxygenation in the preterm infant for many years, but its use as a clinical tool has remained elusive. This has partly been due to the challenges of providing a continuous quantitative measurement that is valid an...

  17. 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...

  18. 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...

  19. [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.

  20. Characterisation of structure-dependent functional properties of lignin with infrared spectroscopy

    NARCIS (Netherlands)

    Boeriu, C.G.; Bravo, D.; Gosselink, R.J.A.; Dam, van J.E.G.

    2004-01-01

    Fourier-transformed infrared spectroscopy (FT-IR) was evaluated as an analytical technique for the estimation of the chemical composition and functional properties of lignin. A sample set containing various non-wood, hardwood and softwood lignins isolated by different processing technologies was

  1. 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

  2. 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.

  3. Champ de production littéraire: impérialisme sociologique ou esthétisation de la socologie?

    Directory of Open Access Journals (Sweden)

    Birešev Ana

    2007-01-01

    Full Text Available (francuski Dans la première partie de ce texte l’auteure traite des conséquences théoriques et méthodologiques de l’utilisation du concept de champ de Pierre Bourdieu dans l’exploration du domaine de la production littéraire. Ces conséquences sont examinées à travers les oppositions caractéristiques de la sociologie traditionnelle de l’art et de la littérature, entre la sociologie et l’herméneutique, l’analyse externe et l’analyse interne, le contexte et le texte, le contenu et la forme, le social et l’esthétique. La deuxième partie est consacrée à l’analyse des idées principales de la sociologie de la production culturelle de Bourdieu. La théorie du champ littéraire que Bourdieu propose permet de comprendre la spécificité des propriétés et des lois du champ de la production littéraire. On examine ici dans quelle mesure ce sociologue a modifié sa méthode d’analyse pour construire réellement le champ des producteurs d’oeuvres culturelles, le champ des oeuvres, ainsi que le système des relations qui s’établissent entre ces deux ensembles de relations.

  4. 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

  5. BACKGROUND AND STATE OF THEE ART OF NEAR INFRARED SPECTROSCOPY IN THE FOREST SECTOR BASE

    Directory of Open Access Journals (Sweden)

    Graciela Inês Bolzon de Muñiz

    2012-12-01

    Full Text Available http://dx.doi.org/10.5902/198050987567The 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.

  6. 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

  7. Review of multidimensional data processing approaches for Raman and infrared spectroscopy

    NARCIS (Netherlands)

    Gautam, R.; Vanga, S.; Ariese, F.

    2015-01-01

    Raman and Infrared (IR) spectroscopies provide information about the structure, functional groups and environment of the molecules in the sample. In combination with a microscope, these techniques can also be used to study molecular distributions in heterogeneous samples. Over the past few decades

  8. Near-infrared spectroscopy used to predict soybean seed germination and vigor

    Science.gov (United States)

    The potential of using near-infrared (NIR) spectroscopy for differentiating levels in germination, vigor, and electrical conductivity of soybean seeds was investigated. For the 243 spectral data collected using the Perten DA7200, stratified sampling was used to obtain three calibration sets consisti...

  9. 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.

  10. 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

  11. Potential use of visible and near-infrared spectroscopy for pine ...

    African Journals Online (AJOL)

    The correct identification of pine species is necessary for proper application of wood in forest-based industries, since the quality of each species' wood depends on factors intrinsic to the material. The aim of this study was to evaluate the potential use of near-infrared and visible spectroscopy in the discrimination of pine ...

  12. Infrared multiple photon dissociation spectroscopy of sodium and potassium chlorate anions

    NARCIS (Netherlands)

    Dain, R. P.; Leavitt, C. M.; Oomens, J.; Steill, J. D.; Groenewold, G. S.; van Stipdonk, M. J.

    2010-01-01

    The structures of gas-phase, metal chlorate anions with the formula [M(ClO3)(2)](-), M = Na and K, were determined using tandem mass spectrometry and infrared multiple photon dissociation (IRMPD) spectroscopy. Structural assignments for both anions are based on comparisons of the experimental

  13. Near infrared spectroscopy (NIRS) to monitor tissue haemoglobin (and myoglobin) oxygenation

    NARCIS (Netherlands)

    Scheeren, T. W. L.

    2010-01-01

    Introduction: Tissue oxygenation may be monitored noninvasively by near infrared spectroscopy (NIRS) both on the thenar eminescence (muscle) and on the forehead (brain). Thenar measurement have been used to guide therapy in trauma patients ( 1 ) and to determine the prognosis of septic patients ( 2

  14. 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

  15. Early detection of emerging street drugs by near infrared spectroscopy and chemometrics.

    Science.gov (United States)

    Risoluti, R; Materazzi, S; Gregori, A; Ripani, L

    2016-06-01

    Near-infrared spectroscopy (NIRs) is spreading as the tool of choice for fast and non-destructive analysis and detection of different compounds in complex matrices. This paper investigated the feasibility of using near infrared (NIR) spectroscopy coupled to chemometrics calibration to detect new psychoactive substances in street samples. The capabilities of this approach in forensic chemistry were assessed in the determination of new molecules appeared in the illicit market and often claimed to contain "non-illegal" compounds, although exhibiting important psychoactive effects. The study focused on synthetic molecules belonging to the classes of synthetic cannabinoids and phenethylamines. The approach was validated comparing results with officials methods and has been successfully applied for "in site" determination of illicit drugs in confiscated real samples, in cooperation with the Scientific Investigation Department (Carabinieri-RIS) of Rome. The achieved results allow to consider NIR spectroscopy analysis followed by chemometrics as a fast, cost-effective and useful tool for the preliminary determination of new psychoactive substances in forensic science. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Investigations of the functional states of dendritic cells under different conditioned microenvironments by Fourier transformed infrared spectroscopy.

    Science.gov (United States)

    Dong, Rong; Long, Jinhua; Xu, Xiaoli; Zhang, Chunlin; Wen, Zongyao; Li, Long; Yao, Weijuan; Zeng, Zhu

    2014-01-10

    Dendritic cells are potent and specialized antigen presenting cells, which play a crucial role in initiating and amplifying both the innate and adaptive immune responses. The dendritic cell-based vaccination against cancer has been clinically achieved promising successes. But there are still many challenges in its clinical application, especially for how to identify the functional states. The CD14+ monocytes were isolated from human peripheral blood after plastic adherence and purified to approximately 98% with cocktail immunomagnetic beads. The immature dendritic cells and mature dendritic cells were induced by traditional protocols. The resulting dendritic cells were cocultured with normal cells and cancer cells. The functional state of dendritic cells including immature dendritic cells (imDCs) and mature dendritic cells (mDCs) under different conditioned microenvironments were investigated by Fourier transformed infrared spectroscopy (FTIR) and molecular biological methods. The results of Fourier transformed infrared spectroscopy showed that the gene transcription activity and energy states of dendritic cells were specifically suppressed by tumor cells (P Fourier transformed infrared spectroscopy at given wave numbers were closely correlated with the expression levels of NF-κB (R2:0.69 and R2:0.81, respectively). Our results confirmed that the ratios of absorption intensities of Fourier transformed infrared spectroscopy at given wave numbers were positively correlated with the expression levels of NF-κB, suggesting that Fourier transformed infrared spectroscopy technology could be clinically applied to identify the functional states of dendritic cell when performing dendritic cell-based vaccination. It's significant for the simplification and standardization of dendritic cell-based vaccination clinical preparation protocols.

  17. 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...

  18. 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.

  19. Measurement of soy contents in ground beef using near-infrared spectroscopy

    Science.gov (United States)

    Models for determining contents of soy products in ground beef were developed using near-infrared (NIR) spectroscopy. Samples were prepared by mixing four kinds of soybean protein products (Arconet, toasted soy grits, Profam and textured vegetable protein (TVP)) with ground beef (content from 0%–100...

  20. 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-...

  1. From Selenium- to Tellurium-Based Glass Optical Fibers for Infrared Spectroscopies

    Directory of Open Access Journals (Sweden)

    Jacques Lucas

    2013-05-01

    Full Text Available Chalcogenide glasses are based on sulfur, selenium and tellurium elements, and have been studied for several decades regarding different applications. Among them, selenide glasses exhibit excellent infrared transmission in the 1 to 15 µm region. Due to their good thermo-mechanical properties, these glasses could be easily shaped into optical devices such as lenses and optical fibers. During the past decade of research, selenide glass fibers have been proved to be suitable for infrared sensing in an original spectroscopic method named Fiber Evanescent Wave Spectroscopy (FEWS. FEWS has provided very nice and promising results, for example for medical diagnosis. Then, some sophisticated fibers, also based on selenide glasses, were developed: rare-earth doped fibers and microstructured fibers. In parallel, the study of telluride glasses, which can have transmission up to 28 µm due to its atom heaviness, has been intensified thanks to the DARWIN mission led by the European Space Agency (ESA. The development of telluride glass fiber enables a successful observation of CO2 absorption band located around 15 µm. In this paper we review recent results obtained in the Glass and Ceramics Laboratory at Rennes on the development of selenide to telluride glass optical fibers, and their use for spectroscopy from the mid to the far infrared ranges.

  2. 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.

  3. Bio-analytical applications of mid-infrared spectroscopy using silver halide fiber-optic probes

    International Nuclear Information System (INIS)

    Heise, H.M.; Kuepper, L.; Butvina, L.N.

    2002-01-01

    Infrared-spectroscopy has proved to be a powerful method for the study of various biomedical samples, in particular for in-vitro analysis in the clinical laboratory and for non-invasive diagnostics. In general, the analysis of biofluids such as whole blood, urine, microdialysates and bioreactor broth media takes advantage of the fact that a multitude of analytes can be quantified simultaneously and rapidly without the need for reagents. Progress in the quality of infrared silver halide fibers enabled us to construct several flexible fiber-optic probes of different geometries, which are particularly suitable for the measurement of small biosamples. Recent trends show that dry film measurements by mid-infrared spectroscopy could revolutionize analytical tools in the clinical chemistry laboratory, and an example is given. Infrared diagnostic tools show a promising potential for patients, and minimal-invasive blood glucose assays or skin tissue pathology in particular cannot be left out using mid-infrared fiber-based probes. Other applications include the measurement of skin samples including penetration studies of vitamins and constituents of cosmetic cream formulations. A further field is the micro-domain analysis of biopsy samples from bog mummified corpses, and recent results on the chemistry of dermis and hair samples are reported. Another field of application, for which results are reported, is food analysis and bio-reactor monitoring

  4. 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

  5. Muscle metabolism from near infrared spectroscopy during rhythmic handgrip in humans

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Pott, F; Madsen, P

    1998-01-01

    The rate of metabolism in forearm flexor muscles (MO2) was derived from near-infrared spectroscopy (NIRS-O2) during ischaemia at rest rhythmic handgrip at 15% and 30% of maximal voluntary contraction (MVC), post-exercise muscle ischaemia (PEMI), and recovery in seven subjects. The MO2 was compared...

  6. 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.

  7. 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

  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. Application of miniaturized near-infrared spectroscopy for quality control of extemporaneous orodispersible films.

    Science.gov (United States)

    Foo, Wen Chin; Widjaja, Effendi; Khong, Yuet Mei; Gokhale, Rajeev; Chan, Sui Yung

    2018-02-20

    Extemporaneous oral preparations are routinely compounded in the pharmacy due to a lack of suitable formulations for special populations. Such small-scale pharmacy preparations also present an avenue for individualized pharmacotherapy. Orodispersible films (ODF) have increasingly been evaluated as a suitable dosage form for extemporaneous oral preparations. Nevertheless, as with all other extemporaneous preparations, safety and quality remain a concern. Although the United States Pharmacopeia (USP) recommends analytical testing of compounded preparations for quality assurance, pharmaceutical assays are typically not routinely performed for such non-sterile pharmacy preparations, due to the complexity and high cost of conventional assay methods such as high performance liquid chromatography (HPLC). Spectroscopic methods including Raman, infrared and near-infrared spectroscopy have been successfully applied as quality control tools in the industry. The state-of-art benchtop spectrometers used in those studies have the advantage of superior resolution and performance, but are not suitable for use in a small-scale pharmacy setting. In this study, we investigated the application of a miniaturized near infrared (NIR) spectrometer as a quality control tool for identification and quantification of drug content in extemporaneous ODFs. Miniaturized near infrared (NIR) spectroscopy is suitable for small-scale pharmacy applications in view of its small size, portability, simple user interface, rapid measurement and real-time prediction results. Nevertheless, the challenge with miniaturized NIR spectroscopy is its lower resolution compared to state-of-art benchtop equipment. We have successfully developed NIR spectroscopy calibration models for identification of ODFs containing five different drugs, and quantification of drug content in ODFs containing 2-10mg ondansetron (OND). The qualitative model for drug identification produced 100% prediction accuracy. The quantitative

  10. Polyaniline: The infrared spectroscopy of conducting polymer nanotubes (IUPAC Technical Report)

    Czech Academy of Sciences Publication Activity Database

    Trchová, Miroslava; Stejskal, Jaroslav

    2011-01-01

    Roč. 83, č. 10 (2011), s. 1803-1817 ISSN 0033-4545 R&D Projects: GA MŠk LA09028 Institutional research plan: CEZ:AV0Z40500505 Keywords : aniline oligomers * fourier transform infrared (FTIR) spectroscopy * IUPAC Polymer Division Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.789, year: 2011

  11. Online analysis of wood pellets. Quality parameters by near infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Petersen Julius, Lars; Joergensen, Pia [Dong Energy Power, Fredericia (Denmark); Plejdrup Houmoeller, Lars [Arla Foods amba, Global Ingedients R and D, Videbaek (Denmark); Groenkaer Pedersen, Joan [Academy Engineer Chemistry Fertin Pharma, Vejle (Denmark); Anov, Dan

    2010-07-01

    A near infrared spectroscopy system was installed online in a wood pellet production facility. The objective was to translate real time spectra to useful chemical information, like calorific value, water- and ash content. It was possible to successfully determine water content and calorific value, whereas ash content proved troublesome. (orig.)

  12. 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.

  13. Surface and bulk crystallization of amorphous solid water films: Confirmation of “top-down” crystallization

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Chunqing; Smith, R. Scott; Kay, Bruce D.

    2016-10-01

    The crystallization kinetics of nanoscale amorphous solid water (ASW) films are investigated using temperature-programmed desorption (TPD) and reflection absorption infrared spectroscopy (RAIRS). TPD measurements are used to probe surface crystallization and RAIRS measurements are used to probe bulk crystallization. Isothermal TPD results show that surface crystallization is independent of the film thickness (from 100 to 1000 ML). Conversely, the RAIRS measurements show that the bulk crystallization time increases linearly with increasing film thickness. These results suggest that nucleation and crystallization begin at the ASW/vacuum interface and then the crystallization growth front propagates linearly into the bulk. This mechanism was confirmed by selective placement of an isotopic layer (5% D2O in H2O) at various positions in an ASW (H2O) film. In this case, the closer the isotopic layer was to the vacuum interface, the earlier the isotopic layer crystallized. These experiments provide direct evidence to confirm that ASW crystallization in vacuum proceeds by a “top-down” crystallization mechanism.

  14. Towards a Low-Cost Mobile Subcutaneous Vein Detection Solution Using Near-Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Simon Juric

    2014-01-01

    Full Text Available Excessive venipunctures are both time- and resource-consuming events, which cause anxiety, pain, and distress in patients, or can lead to severe harmful injuries. We propose a low-cost mobile health solution for subcutaneous vein detection using near-infrared spectroscopy, along with an assessment of the current state of the art in this field. The first objective of this study was to get a deeper overview of the research topic, through the initial team discussions and a detailed literature review (using both academic and grey literature. The second objective, that is, identifying the commercial systems employing near-infrared spectroscopy, was conducted using the PubMed database. The goal of the third objective was to identify and evaluate (using the IEEE Xplore database the research efforts in the field of low-cost near-infrared imaging in general, as a basis for the conceptual model of the upcoming prototype. Although the reviewed commercial devices have demonstrated usefulness and value for peripheral veins visualization, other evaluated clinical outcomes are less conclusive. Previous studies regarding low-cost near-infrared systems demonstrated the general feasibility of developing cost-effective vein detection systems; however, their limitations are restricting their applicability to clinical practice. Finally, based on the current findings, we outline the future research direction.

  15. Towards a low-cost mobile subcutaneous vein detection solution using near-infrared spectroscopy.

    Science.gov (United States)

    Juric, Simon; Flis, Vojko; Debevc, Matjaz; Holzinger, Andreas; Zalik, Borut

    2014-01-01

    Excessive venipunctures are both time- and resource-consuming events, which cause anxiety, pain, and distress in patients, or can lead to severe harmful injuries. We propose a low-cost mobile health solution for subcutaneous vein detection using near-infrared spectroscopy, along with an assessment of the current state of the art in this field. The first objective of this study was to get a deeper overview of the research topic, through the initial team discussions and a detailed literature review (using both academic and grey literature). The second objective, that is, identifying the commercial systems employing near-infrared spectroscopy, was conducted using the PubMed database. The goal of the third objective was to identify and evaluate (using the IEEE Xplore database) the research efforts in the field of low-cost near-infrared imaging in general, as a basis for the conceptual model of the upcoming prototype. Although the reviewed commercial devices have demonstrated usefulness and value for peripheral veins visualization, other evaluated clinical outcomes are less conclusive. Previous studies regarding low-cost near-infrared systems demonstrated the general feasibility of developing cost-effective vein detection systems; however, their limitations are restricting their applicability to clinical practice. Finally, based on the current findings, we outline the future research direction.

  16. 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.

  17. 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.

  18. High resolution spectroscopy of six SOCl2 isotopologues from the microwave to the far-infrared

    Science.gov (United States)

    Martin-Drumel, M. A.; Roucou, A.; Brown, G. G.; Thorwirth, S.; Pirali, O.; Mouret, G.; Hindle, F.; McCarthy, M. C.; Cuisset, A.

    2016-02-01

    Despite its potential role as an atmospheric pollutant, thionyl chloride, SOCl2, remains poorly characterized in the gas phase. In this study, the pure rotational and ro-vibrational spectra of six isotopologues of this molecule, all detected in natural abundance, have been extensively studied from the cm-wave band to the far-infrared region by means of three complementary techniques: chirped-pulse Fourier transform microwave spectroscopy, sub-millimeter-wave spectroscopy using frequency multiplier chain, and synchrotron-based far-infrared spectroscopy. Owing to the complex line pattern which results from two nuclei with non-zero spins, new, high-level quantum-chemical calculations of the hyperfine structure played a crucial role in the spectroscopic analysis. From the combined experimental and theoretical work, an accurate semi-experimental equilibrium structure (reSE) of SOCl2 has been derived. With the present data, spectroscopy-based methods can now be applied with confidence to detect and monitor this species, either by remote sensing or in situ.

  19. Detecting adulterants in milk with lower cost mid-infrared and Raman spectroscopy

    Science.gov (United States)

    Lee, Changwon; Wang, Wenbo; Wilson, Benjamin K.; Connett, Marie; Keller, Matthew D.

    2018-02-01

    Adulteration of milk for economic gains is a widespread issue throughout the developing world that can have far-reaching health and nutritional impacts. Milk analysis technologies, such as infrared spectroscopy, can screen for adulteration, but the cost of these technologies has prohibited their use in low resource settings. Recent developments in infrared and Raman spectroscopy hardware have led to commercially available low-cost devices. In this work, we evaluated the performance of two such spectrometers in detecting and quantifying the presence of milk adulterants. Five common adulterants - ammonium sulfate, melamine, sodium bicarbonate, sucrose, and urea, were spiked into five different raw cow and goat milk samples at different concentrations. Collected MIR and Raman spectra were analyzed using partial least squares regression. The limit of detection (LOD) for each adulterant was determined to be in the range of 0.04 to 0.28% (400 to 2800 ppm) using MIR spectroscopy. Raman spectroscopy showed similar LOD's for some of the adulterants, notably those with strong amine group signals, and slightly higher LOD's (up to 1.0%) for other molecules. Overall, the LODs were comparable to other spectroscopic milk analyzers on the market, and they were within the economically relevant concentration range of 100 to 4000 ppm. These lower cost spectroscopic devices therefore appear to hold promise for use in low resource settings.

  20. 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.

  1. Cerebral hemodynamics measured with simultaneous PET and near-infrared spectroscopy in humans

    DEFF Research Database (Denmark)

    Rostrup, Egill; Law, Ian; Pott, Frank

    2002-01-01

    Near-infrared spectroscopy (NIRS) enables continuous non-invasive quantification of blood and tissue oxygenation, and may be useful for quantification of cerebral blood volume (CBV) changes. In this study, changes in cerebral oxy- and deoxyhemoglobin were compared to corresponding changes in CBF ...

  2. 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.

  3. 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.

  4. 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)

  5. 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...

  6. Sequence-Dependent Mechanism of DNA Oligonucleotide Dehybridization Resolved through Infrared Spectroscopy.

    Science.gov (United States)

    Sanstead, Paul J; Stevenson, Paul; Tokmakoff, Andrei

    2016-09-14

    Despite its important role in biology and nanotechnology, many questions remain regarding the molecular mechanism and dynamics by which oligonucleotides recognize and hybridize to their complementary sequence. The thermodynamics and kinetics of DNA oligonucleotide hybridization and dehybridization are often assumed to involve an all-or-nothing two-state dissociation pathway, but deviations from this behavior can be considerable even for short sequences. We introduce a new strategy to characterize the base-pair-specific thermal dissociation mechanism of DNA oligonucleotides through steady-state and time-resolved infrared spectroscopy. Experiments are interpreted with a lattice model to provide a structure-specific interpretation. This method is applied to a model set of self-complementary 10-base-pair sequences in which the placement of GC base pairs is varied in an otherwise AT strand. Through a combination of Fourier transform infrared and two-dimensional infrared spectroscopy, experiments reveal varying degrees of deviation from simple two-state behavior. As the temperature is increased, duplexes dissociate through a path in which the terminal bases fray, without any significant contribution from loop configurations. Transient temperature jump experiments reveal time scales of 70-100 ns for fraying and 10-30 μs for complete dissociation near the melting temperature. Whether or not frayed states are metastable intermediates or short-lived configurations during the full dissociation of the duplex is dictated by the nucleobase sequence.

  7. 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.

  8. Self-assembling peptide hydrogels immobilized on silicon surfaces

    International Nuclear Information System (INIS)

    Franchi, Stefano; Battocchio, Chiara; Galluzzi, Martina; Navisse, Emanuele; Zamuner, Annj; Dettin, Monica; Iucci, Giovanna

    2016-01-01

    The hydrogels of self-assembling ionic complementary peptides have collected in the scientific community increasing consensus as mimetics of the extracellular matrix that can offer 3D supports for cell growth or be vehicles for the delivery of stem cells or drugs. Such scaffolds have also been proposed as bone substitutes for small defects as they promote beneficial effects on human osteoblasts. In this context, our research deals with the introduction of a layer of self-assembling peptides on a silicon surface by covalent anchoring and subsequent physisorption. In this work, we present a spectroscopic investigation of the proposed bioactive scaffolds, carried out by surface-sensitive spectroscopic techniques such as XPS (X-ray photoelectron spectroscopy) and RAIRS (Reflection Absorption Infrared Spectroscopy) and by state-of-the-art synchrotron radiation methodologies such as angle dependent NEXAFS (Near Edge X-ray Absorption Fine Structure). XPS studies confirmed the change in the surface composition in agreement with the proposed enrichments, and led to assess the self-assembling peptide chemical stability. NEXAFS spectra, collected in angular dependent mode at the N K-edge, allowed to investigate the self-assembling behavior of the macromolecules, as well as to determine their molecular orientation on the substrate. Furthermore, Infrared Spectroscopy measurements demonstrated that the peptide maintains its secondary structure (β-sheet anti-parallel) after deposition on the silicon surface. The complementary information acquired by means of XPS, NEXAFS and RAIRS lead to hypothesize a “layer-by-layer” arrangement of the immobilized peptides, giving rise to an ordered 3D nanostructure. - Highlights: • A self-assembling peptide (SAP) was covalently immobilized of on a flat silicon surface. • A physisorbed SAP layer was grown on top of the covalently immobilized peptide layer. • Molecular order and orientation of the peptide overlayer on the flat silicon

  9. Self-assembling peptide hydrogels immobilized on silicon surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Franchi, Stefano; Battocchio, Chiara; Galluzzi, Martina; Navisse, Emanuele [Department of Sciences, University “Roma Tre”, Via della Vasca Navale 79, Roma, 00146 (Italy); Zamuner, Annj; Dettin, Monica [Department of Industrial Engineering, University of Padua, Via Marzolo, 9, Padua, 35131 (Italy); Iucci, Giovanna, E-mail: giovanna.iucci@uniroma3.it [Department of Sciences, University “Roma Tre”, Via della Vasca Navale 79, Roma, 00146 (Italy)

    2016-12-01

    The hydrogels of self-assembling ionic complementary peptides have collected in the scientific community increasing consensus as mimetics of the extracellular matrix that can offer 3D supports for cell growth or be vehicles for the delivery of stem cells or drugs. Such scaffolds have also been proposed as bone substitutes for small defects as they promote beneficial effects on human osteoblasts. In this context, our research deals with the introduction of a layer of self-assembling peptides on a silicon surface by covalent anchoring and subsequent physisorption. In this work, we present a spectroscopic investigation of the proposed bioactive scaffolds, carried out by surface-sensitive spectroscopic techniques such as XPS (X-ray photoelectron spectroscopy) and RAIRS (Reflection Absorption Infrared Spectroscopy) and by state-of-the-art synchrotron radiation methodologies such as angle dependent NEXAFS (Near Edge X-ray Absorption Fine Structure). XPS studies confirmed the change in the surface composition in agreement with the proposed enrichments, and led to assess the self-assembling peptide chemical stability. NEXAFS spectra, collected in angular dependent mode at the N K-edge, allowed to investigate the self-assembling behavior of the macromolecules, as well as to determine their molecular orientation on the substrate. Furthermore, Infrared Spectroscopy measurements demonstrated that the peptide maintains its secondary structure (β-sheet anti-parallel) after deposition on the silicon surface. The complementary information acquired by means of XPS, NEXAFS and RAIRS lead to hypothesize a “layer-by-layer” arrangement of the immobilized peptides, giving rise to an ordered 3D nanostructure. - Highlights: • A self-assembling peptide (SAP) was covalently immobilized of on a flat silicon surface. • A physisorbed SAP layer was grown on top of the covalently immobilized peptide layer. • Molecular order and orientation of the peptide overlayer on the flat silicon

  10. 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.

  11. Les inscriptions funéraires au cimetière d’Aïn El-Beida (Oran) : état des lieux

    OpenAIRE

    Hirreche Baghdad, Mohamed

    2016-01-01

    Ce papier résulte d’un projet établissement inscrit au CRASC (2009-2013) intitulé : « les inscriptions sur les stèles funéraires dans l’ouest algérien : permanence et évolution ». La problématique de ce projet est la suivante : qu’écrivent les algériens sur les tombes de leurs proches et comment expliquer la divergence ou la ressemblance des contenus épigraphiques des stèles funéraires ? La première partie de la question s’intéresse à l’état des lieux de l’épigraphie au cimetière d’Aïn El-Bei...

  12. Screening suspected counterfeit Viagra and imitations of Viagra with near-infrared spectroscopy.

    NARCIS (Netherlands)

    Vredenbregt, M J; Blok-Tip, L; Hoogerbrugge, Ronald; Barends, D M; Kaste, D de

    2006-01-01

    We describe a near-infrared spectroscopy (NIRS) method for fast-screening Viagra tablets, counterfeit Viagra tablets, and imitations of Viagra. The method can (1) check the homogeneity of a batch; (2) distinguish counterfeits and imitations from authentic Viagra; (3) screen for the presence of

  13. Bound states of water in gelatin discriminated by near-infrared spectroscopy

    Science.gov (United States)

    Otsuka, Yukiko; Shirakashi, Ryo; Hirakawa, Kazuhiko

    2017-11-01

    By near-infrared spectroscopy, we classified water molecules in hydrated gelatin membranes in a drying process. Absorbance spectra in the frequency range of 4500-5500 cm-1 were resolved into three peaks, S0, S1, and S2, that correspond to water molecules with different hydrogen bond states. From the areas of the absorbance peaks as a function of the water content of gelatin, together with the information on the freezing properties of water measured by differential scanning calorimetry, we found that, when the water content is less than 20%, free water disappears and only weakly and strongly bound waters remain. We also found that the weakly bound water consists of S0, S1, and S2 water molecules with a simple composition of \\text{S}0:\\text{S}1:\\text{S}2 ≈ 1:2:0. Using this information, most of the freezable water was determined to be free water. Our classification provides a simple method of estimating the retention and freezing properties of processed foods or drugs by infrared spectroscopy.

  14. Application of Near-Infrared and Fourier Transform Infrared Spectroscopy in the Characterization of Ligand-Induced Conformation Changes in Folate Binding Protein Purified from Bovine Milk

    DEFF Research Database (Denmark)

    Bruun, Susanne Wrang; Holm, Jan; Hansen, Steen Ingemann

    2006-01-01

    Fourier transform infrared (FT-IR) and near-infrared (NIR) spectroscopy have been applied to detect structural alterations in folate binding protein (FBP) induced by ligation in different buffer types. The amide I region pointed to a beta-sheet to alpha-helix transition upon ligation in acetate...

  15. New PLS analysis approach to wine volatile compounds characterization by near infrared spectroscopy (NIR).

    Science.gov (United States)

    Genisheva, Z; Quintelas, C; Mesquita, D P; Ferreira, E C; Oliveira, J M; Amaral, A L

    2018-04-25

    This work aims to explore the potential of near infrared (NIR) spectroscopy to quantify volatile compounds in Vinho Verde wines, commonly determined by gas chromatography. For this purpose, 105 Vinho Verde wine samples were analyzed using Fourier transform near infrared (FT-NIR) transmission spectroscopy in the range of 5435 cm -1 to 6357 cm -1 . Boxplot and principal components analysis (PCA) were performed for clusters identification and outliers removal. A partial least square (PLS) regression was then applied to develop the calibration models, by a new iterative approach. The predictive ability of the models was confirmed by an external validation procedure with an independent sample set. The obtained results could be considered as quite good with coefficients of determination (R 2 ) varying from 0.94 to 0.97. The current methodology, using NIR spectroscopy and chemometrics, can be seen as a promising rapid tool to determine volatile compounds in Vinho Verde wines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. [A method of temperature measurement for hot forging with surface oxide based on infrared spectroscopy].

    Science.gov (United States)

    Zhang, Yu-cun; Qi, Yan-de; Fu, Xian-bin

    2012-05-01

    High temperature large forging is covered with a thick oxide during forging. It leads to a big measurement data error. In this paper, a method of measuring temperature based on infrared spectroscopy is presented. It can effectively eliminate the influence of surface oxide on the measurement of temperature. The method can measure the surface temperature and emissivity of the oxide directly using the infrared spectrum. The infrared spectrum is radiated from surface oxide of forging. Then it can derive the real temperature of hot forging covered with the oxide using the heat exchange equation. In order to greatly restrain interference spectroscopy through included in the received infrared radiation spectrum, three interference filter system was proposed, and a group of optimal gap parameter values using spectral simulation were obtained. The precision of temperature measurement was improved. The experimental results show that the method can accurately measure the surface temperature of high temperature forging covered with oxide. It meets the requirements of measurement accuracy, and the temperature measurement method is feasible according to the experiment result.

  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. 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

  19. Investigation of vegetation history of buried chernozem soils using near-infrared spectroscopy (NIRS)

    Czech Academy of Sciences Publication Activity Database

    Vysloužilová, B.; Ertlen, D.; Šefrna, L.; Novák, T.; Virágh, K.; Rué, M.; Campaner, A.; Dreslerová, Dagmar; Schwartz, D.

    2015-01-01

    Roč. 365, 16 April (2015), s. 203-211 ISSN 1040-6182 Institutional support: RVO:67985912 Keywords : Holocene * paleopedology * paleoecology * near-infrared spectroscopy * chernozem * buried paleosol Subject RIV: DF - Soil Science Impact factor: 2.067, year: 2015

  20. Long-wave, infrared laser-induced breakdown (LIBS) spectroscopy emissions from energetic materials.

    Science.gov (United States)

    Yang, Clayton S-C; Brown, Ei E; Hommerich, Uwe; Jin, Feng; Trivedi, Sudhir B; Samuels, Alan C; Snyder, A Peter

    2012-12-01

    Laser-induced breakdown spectroscopy (LIBS) has shown great promise for applications in chemical, biological, and explosives sensing and has significant potential for real-time standoff detection and analysis. In this study, LIBS emissions were obtained in the mid-infrared (MIR) and long-wave infrared (LWIR) spectral regions for potential applications in explosive material sensing. The IR spectroscopy region revealed vibrational and rotational signatures of functional groups in molecules and fragments thereof. The silicon-based detector for conventional ultraviolet-visible LIBS operations was replaced with a mercury-cadmium-telluride detector for MIR-LWIR spectral detection. The IR spectral signature region between 4 and 12 μm was mined for the appearance of MIR and LWIR-LIBS emissions directly indicative of oxygenated breakdown products as well as dissociated, and/or recombined sample molecular fragments. Distinct LWIR-LIBS emission signatures from dissociated-recombination sample molecular fragments between 4 and 12 μm are observed for the first time.

  1. 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.

  2. Multivariate Calibration Models for Sorghum Composition using Near-Infrared Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wolfrum, E.; Payne, C.; Stefaniak, T.; Rooney, W.; Dighe, N.; Bean, B.; Dahlberg, J.

    2013-03-01

    NREL developed calibration models based on near-infrared (NIR) spectroscopy coupled with multivariate statistics to predict compositional properties relevant to cellulosic biofuels production for a variety of sorghum cultivars. A robust calibration population was developed in an iterative fashion. The quality of models developed using the same sample geometry on two different types of NIR spectrometers and two different sample geometries on the same spectrometer did not vary greatly.

  3. Gastric cancer differentiation using Fourier transform near-infrared spectroscopy with unsupervised pattern recognition

    Science.gov (United States)

    Yi, Wei-song; Cui, Dian-sheng; Li, Zhi; Wu, Lan-lan; Shen, Ai-guo; Hu, Ji-ming

    2013-01-01

    The manuscript has investigated the application of near-infrared (NIR) spectroscopy for differentiation gastric cancer. The 90 spectra from cancerous and normal tissues were collected from a total of 30 surgical specimens using Fourier transform near-infrared spectroscopy (FT-NIR) equipped with a fiber-optic probe. Major spectral differences were observed in the CH-stretching second overtone (9000-7000 cm-1), CH-stretching first overtone (6000-5200 cm-1), and CH-stretching combination (4500-4000 cm-1) regions. By use of unsupervised pattern recognition, such as principal component analysis (PCA) and cluster analysis (CA), all spectra were classified into cancerous and normal tissue groups with accuracy up to 81.1%. The sensitivity and specificity was 100% and 68.2%, respectively. These present results indicate that CH-stretching first, combination band and second overtone regions can serve as diagnostic markers for gastric cancer.

  4. Nondestructive detection of zebra chip disease in potatoes using near-infrared spectroscopy

    Science.gov (United States)

    Near-Infrared (NIR) spectroscopy in the wavelength region from 900 nm to 2600 nm was evaluated as the basis for a rapid, non-destructive method for the detection of Zebra Chip disease in potatoes and the measurement of sugar concentrations in affected tubers. Using stepwise regression in conjunction...

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. Characterization of Modified and Polymer Coated Alumina Surfaces by Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Ashraf Yehia El-Naggar

    2013-01-01

    Full Text Available The prepared, modified, and coated alumina surfaces were characterized by infrared spectroscopy (FTIR to investigate the surface properties of the individual and double modified samples. FTIR helps in reporting the changes occurred in hydroxyl groups as well as the structure changes as a result of thermal treating, hydrothermal treating, silylation treating, alkali metal treating, coating, and bonding with polymer. FTIR spectroscopy represents the strength and abundance of surface acidic OH which determine the adsorption properties of polar and nonpolar sorbents. Generally, all treated samples exhibit decrease of OH groups compared with those of parent ones producing alumina surfaces of different adsorptive powers.

  10. Dynamical interactions between solute and solvent studied by nonlinear infrared spectroscopy

    International Nuclear Information System (INIS)

    Ohta, K.; Tominaga, K.

    2006-01-01

    Interactions between solute and solvent play an important role in chemical reaction dynamics and in many relaxation processes in condensed phases. Recently third-order nonlinear infrared (IR) spectroscopy has shown to be useful to investigate solute-solvent interaction and dynamics of the vibrational transition. These studies provide detailed information on the energy relaxation of the vibrationally excited state, and the time scale and the magnitude of the time correlation functions of the vibrational frequency fluctuations. In this work we have studied vibrational energy relaxation (VER) of solutions and molecular complexes by nonlinear IR spectroscopy, especially IR pump-probe method, to understand the microscopic interactions in liquids. (authors)

  11. 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.

  12. Infrared-x-ray pump-probe spectroscopy of the NO molecule

    International Nuclear Information System (INIS)

    Guimaraes, F.F.; Felicissimo, V.C.; Kimberg, V.; Gel'mukhanov, F.; Aagren, H.; Cesar, A.

    2005-01-01

    Two color infrared-x-ray pump-probe spectroscopy of the NO molecule is studied theoretically and numerically in order to obtain a deeper insight of the underlying physics and of the potential of this suggested technology. From the theoretical investigation a number of conclusions could be drawn: It is found that the phase of the infrared field strongly influences the trajectory of the nuclear wave packet, and hence, the x-ray spectrum. The trajectory experiences fast oscillations with the vibrational frequency with a modulation due to the anharmonicity of the potential. The dependences of the x-ray spectra on the delay time, the duration, and the shape of the pulses are studied in detail. It is shown that the x-ray spectrum keep memory about the infrared phase after the pump field left the system. This memory effect is sensitive to the time of switching-off the pump field and the Rabi frequency. The phase effect takes maximum value when the duration of the x-ray pulse is one-fourth of the infrared field period, and can be enhanced by a proper control of the duration and intensity of the pump pulse. The manifestation of the phase is different for oriented and disordered molecules and depends strongly on the intensity of the pump radiation

  13. Infrared x-ray pump-probe spectroscopy of the NO molecule

    Science.gov (United States)

    Guimarães, F. F.; Kimberg, V.; Felicíssimo, V. C.; Gel'Mukhanov, F.; Cesar, A.; Ågren, H.

    2005-07-01

    Two color infrared x-ray pump-probe spectroscopy of the NO molecule is studied theoretically and numerically in order to obtain a deeper insight of the underlying physics and of the potential of this suggested technology. From the theoretical investigation a number of conclusions could be drawn: It is found that the phase of the infrared field strongly influences the trajectory of the nuclear wave packet, and hence, the x-ray spectrum. The trajectory experiences fast oscillations with the vibrational frequency with a modulation due to the anharmonicity of the potential. The dependences of the x-ray spectra on the delay time, the duration, and the shape of the pulses are studied in detail. It is shown that the x-ray spectrum keep memory about the infrared phase after the pump field left the system. This memory effect is sensitive to the time of switching-off the pump field and the Rabi frequency. The phase effect takes maximum value when the duration of the x-ray pulse is one-fourth of the infrared field period, and can be enhanced by a proper control of the duration and intensity of the pump pulse. The manifestation of the phase is different for oriented and disordered molecules and depends strongly on the intensity of the pump radiation.

  14. Voxel-based measurement sensitivity of spatially resolved near-infrared spectroscopy in layered tissues.

    Science.gov (United States)

    Niwayama, Masatsugu

    2018-03-01

    We quantitatively investigated the measurement sensitivity of spatially resolved spectroscopy (SRS) across six tissue models: cerebral tissue, a small animal brain, the forehead of a fetus, an adult brain, forearm muscle, and thigh muscle. The optical path length in the voxel of the model was analyzed using Monte Carlo simulations. It was found that the measurement sensitivity can be represented as the product of the change in the absorption coefficient and the difference in optical path length in two states with different source-detector distances. The results clarified the sensitivity ratio between the surface layer and the deep layer at each source-detector distance for each model and identified changes in the deep measurement area when one of the detectors was close to the light source. A comparison was made with the results from continuous-wave spectroscopy. The study also identified measurement challenges that arise when the surface layer is inhomogeneous. Findings on the measurement sensitivity of SRS at each voxel and in each layer can support the correct interpretation of measured values when near-infrared oximetry or functional near-infrared spectroscopy is used to investigate different tissue structures. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  15. Control of Refining Processes on Mid-Distillates by Near Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Zanier-Szydlowski N.

    1999-07-01

    Full Text Available The purpose of this paper is to demonstrate the accuracy of physicochemical determinations based on equations calculated by multivariate analysis of near infrared spectra which gives access to simultaneous analyses both on-line and off-line. Detailed results concerning the determination of the refractive index at 20°C, the density, the weight% of hydrogen, the % of aromatic carbon, the weight% of mono-, di- and total aromatics and the cetane number on mid-distillates are given in a shorter time than using the conventional approach by standardized methods. It is shown that near infrared spectroscopy combined with chemometrics should allow detailed and precise comparisons of the hydrotreatment process efficiencies.

  16. [Research progress and application prospect of near infrared spectroscopy in soil nutrition analysis].

    Science.gov (United States)

    Ding, Hai-quan; Lu, Qi-peng

    2012-01-01

    "Digital agriculture" or "precision agriculture" is an important direction of modern agriculture technique. It is the combination of the modern information technique and traditional agriculture and becomes a hotspot field in international agriculture research in recent years. As a nondestructive, real-time, effective and exact analysis technique, near infrared spectroscopy, by which precision agriculture could be carried out, has vast prospect in agrology and gradually gained the recognition. The present paper intends to review the basic theory of near infrared spectroscopy and its applications in the field of agrology, pointing out that the direction of NIR in agrology should based on portable NIR spectrograph in order to acquire qualitative or quantitative information from real-time measuring in field. In addition, NIRS could be combined with space remote sensing to macroscopically control the way crop is growing and the nutrition crops need, to change the current state of our country's agriculture radically.

  17. 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.

  18. 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.)

  19. 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.)

  20. 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.

  1. 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

  2. The applicability of Fourier transform infrared (FT-IR) spectroscopy in waste management

    International Nuclear Information System (INIS)

    Smidt, Ena; Meissl, Katharina

    2007-01-01

    State and stability or reactivity of waste materials are important properties that must be determined to obtain information about the future behavior and the emission potential of the materials. Different chemical and biological parameters are used to describe the stage of organic matter in waste materials. Fourier transform infrared spectroscopy provides information about the chemistry of waste materials in a general way. Several indicator bands that are referred to functional groups represent components or metabolic products. Their presence and intensity or their absence shed light on the phase of degradation or stabilization. The rapid assessment of the stage of organic matter decomposition is a very important field of application. Therefore, infrared spectroscopy is an appropriate tool for process and quality control, for the assessment of abandoned landfills and for checking of the successful landfill remediation. A wide range of applications are presented in this study for different waste materials. Progressing stages of a typical yard/kitchen waste composting process are shown. The fate of anaerobically 'stabilized' leftovers in a subsequent liquid aerobic process is revealed by spectroscopic characteristics. A compost that underwent the biological stabilization process is distinguished from a 'substrate' that comprises immature biogenic waste mixed with mineral compounds. Infrared spectra of freeze-dried leachate from untreated and aerated landfill material prove the effect of the aerobic treatment during 10 weeks in laboratory-scale experiments

  3. 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.

  4. Predicting the ethanol potential of wheat straw using near-infrared spectroscopy and chemometrics

    DEFF Research Database (Denmark)

    Rinnan, Åsmund; Bruun, Sander; Lindedam, Jane

    2017-01-01

    of using near-infrared spectroscopy to evaluate the ethanol potential of wheat straw by analyzing more than 1000 samples from different wheat varieties and growth conditions. During the calibration model development, the prime emphasis was to investigate the correlation structure between the two major...

  5. Food Safety Evaluation Based on Near Infrared Spectroscopy and Imaging: A Review.

    Science.gov (United States)

    Fu, Xiaping; Ying, Yibin

    2016-08-17

    In recent years, due to the increasing consciousness of food safety and human health, much progress has been made in developing rapid and nondestructive techniques for the evaluation of food hazards, food authentication, and traceability. Near infrared (NIR) spectroscopy and imaging techniques have gained wide acceptance in many fields because of their advantages over other analytical techniques. Following a brief introduction of NIR spectroscopy and imaging basics, this review mainly focuses on recent NIR spectroscopy and imaging applications for food safety evaluation, including (1) chemical hazards detection; (2) microbiological hazards detection; (3) physical hazards detection; (4) new technology-induced food safety concerns; and (5) food traceability. The review shows NIR spectroscopy and imaging to be effective tools that will play indispensable roles for food safety evaluation. In addition, on-line/real-time applications of these techniques promise to be a huge growth field in the near future.

  6. Orthostatic leg blood volume changes assessed by near-infrared spectroscopy

    DEFF Research Database (Denmark)

    Truijen, J; Kim, Y S; Krediet, C T P

    2012-01-01

    posture, volume accumulation in small blood vessels contributes significantly to the total fluid volume accumulated in the legs. Considering that near-infrared spectroscopy (NIRS) tracks postural blood volume changes within the small blood vessels of the lower leg, we evaluated the NIRS-determined changes......-linear accumulation of blood volume in the small vessels of the leg, with an initial fast phase followed by a more gradual increase at least partly contributing to the relocation of fluid during orthostatic stress....

  7. 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....

  8. Real time near-infrared Raman spectroscopy for the diagnosis of nasopharyngeal cancer.

    Science.gov (United States)

    Ming, Lim Chwee; Gangodu, Nagaraja Rao; Loh, Thomas; Zheng, Wei; Wang, Jianfeng; Lin, Kan; Zhiwei, Huang

    2017-07-25

    Near-infrared (NIR) Raman spectroscopy has been investigated as a tool to differentiate nasopharyngeal cancer (NPC) from normal nasopharyngeal tissue in an ex-vivo setting. Recently, we have miniaturized the fiber-optic Raman probe to investigate its utility in real time in-vivo surveillance of NPC patients. A posterior probability model using partial linear square (PLS) mathematical technique was constructed to verify the sensitivity and specificity of Raman spectroscopy in diagnosing NPC from post-irradiated and normal tissue using a diagnostic algorithm from three significant latent variables. NIR-Raman signals of 135 sites were measured from 79 patients with either newly diagnosed NPC (N = 12), post irradiated nasopharynx (N = 37) and normal nasopharynx (N = 30). The mean Raman spectra peaks identified differences at several Raman peaks at 853 cm-1, 940 cm-1, 1078 cm-1, 1335 cm-1, 1554 cm-1, 2885 cm-1 and 2940 cm-1 in the three different nasopharyngeal conditions. The sensitivity and specificity of distinguishing Raman signatures among normal nasopharynx versus NPC and post-irradiated nasopharynx versus NPC were 91% and 95%; and 77% and 96% respectively. Real time near-infrared Raman spectroscopy has a high specificity in distinguishing malignant from normal nasopharyngeal tissue in vivo, and may be investigated as a novel non-invasive surveillance tool in patients with nasopharyngeal cancer.

  9. Differentiation and detection of microorganisms using Fourier transform infrared photoacoustic spectroscopy

    Science.gov (United States)

    Irudayaraj, Joseph; Yang, Hong; Sakhamuri, Sivakesava

    2002-03-01

    Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) was used to differentiate and identify microorganisms on a food (apple) surface. Microorganisms considered include bacteria (Lactobacillus casei, Bacillus cereus, and Escherichia coli), yeast (Saccharomyces cerevisiae), and fungi (Aspergillus niger and Fusarium verticilliodes). Discriminant analysis was used to differentiate apples contaminated with the different microorganisms from uncontaminated apple. Mahalanobis distances were calculated to quantify the differences. The higher the value of the Mahalanobis distance metric between different microorganisms, the greater is their difference. Additionally, pathogenic (O157:H7) E. coli was successfully differentiated from non-pathogenic strains. Results demonstrate that FTIR-PAS spectroscopy has the potential to become a non-destructive analysis tool in food safety related research.

  10. Fourier Transform Infrared Spectroscopy (FTIR) as a Tool for the Identification and Differentiation of Pathogenic Bacteria.

    Science.gov (United States)

    Zarnowiec, Paulina; Lechowicz, Łukasz; Czerwonka, Grzegorz; Kaca, Wiesław

    2015-01-01

    Methods of human bacterial pathogen identification need to be fast, reliable, inexpensive, and time efficient. These requirements may be met by vibrational spectroscopic techniques. The method that is most often used for bacterial detection and identification is Fourier transform infrared spectroscopy (FTIR). It enables biochemical scans of whole bacterial cells or parts thereof at infrared frequencies (4,000-600 cm(-1)). The recorded spectra must be subsequently transformed in order to minimize data variability and to amplify the chemically-based spectral differences in order to facilitate spectra interpretation and analysis. In the next step, the transformed spectra are analyzed by data reduction tools, regression techniques, and classification methods. Chemometric analysis of FTIR spectra is a basic technique for discriminating between bacteria at the genus, species, and clonal levels. Examples of bacterial pathogen identification and methods of differentiation up to the clonal level, based on infrared spectroscopy, are presented below.

  11. Solid-state characterization of triamcinolone acetonide nanosuspensiones by X-ray spectroscopy, ATR Fourier transforms infrared spectroscopy and differential scanning calorimetry analysis

    Directory of Open Access Journals (Sweden)

    Eva García-Millán

    2017-12-01

    Full Text Available The data presented in this article describe the physical state of the triamcinolone acetonide (TA in nanosuspension stabilized with polyvinyl alcohol (PVA and poloxamer 407 (PL. The data were assessed by X-ray spectroscopy, ATR Fourier transforms infrared spectroscopy measurements (FTIR, and Differential scanning calorimetry (DSC analysis. PVA, PL and polymeric mixture (PVA and PL were compared with nanosuspension and the interactions between drug triamcinolone acetonide and polymers were studied. The data are related and are complementary to the research article entitle “Improved release of triamcinolone acetonide from medicated soft contact lenses loaded with drug nanosuspensions” (García-Millán et al., 2017 [1]. Keywords: Triamcinolona acetonide nanosuspensiones, X-ray spectroscopy, FTIR spectroscopy, DSC

  12. 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.

  13. 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...

  14. Inline monitoring of adsorption of Butane Isomers with near infrared spectroscopy: Drift Correction in time based experiments

    NARCIS (Netherlands)

    Ferreira, A.; Boelens, H.F.M.; Westerhuis, J.A.

    2005-01-01

    Near-infrared (NIR) spectroscopy is used to monitor online a large variety of processes. Hydrocarbons with their strong NIR spectral signature are good candidate analytes. For this work, the sorption data are measured in a manometric setup coupled with online NIR spectroscopy, to monitor the bulk

  15. Comparing predictive ability of Laser-Induced Breakdown Spectroscopy to Near Infrared Spectroscopy for soil texture and organic carbon determination

    DEFF Research Database (Denmark)

    Knadel, Maria; Peng, Yi; Gislum, René

    Soil organic carbon (SOC) and texture have a practical value for agronomy and the environment. Thus, alternative techniques to supplement or substitute for the expensive conventional analysis of soil are developed. Here the feasibility of laser-induced breakdown spectroscopy (LIBS) to determine SOC...... and texture was tested and compared with near infrared spectroscopy (NIRS) technique and traditional laboratory analysis. Calibration models were developed on 50 topsoil samples. For all properties except silt, higher predictive ability of LIBS than NIRS models was obtained. Successful calibrations indicate...... that LIBS can be used as a fast and reliable method for SOC and texture estimation....

  16. 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.

  17. 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.

  18. Two-color mid-infrared spectroscopy of optically doped semiconductors

    International Nuclear Information System (INIS)

    Forcales, M.; Klik, M.A.J.; Vinh, N.Q.; Phillips, J.; Wells, J-P.R.; Gregorkiewicz, T.

    2003-01-01

    Optical doping is an attractive method to tailor photonic properties of semiconductor matrices for development of solid-state electroluminescent structures. For practical applications, thermal stability of emission obtained from these materials is required. Thermal processes can be conveniently investigated by two-color spectroscopy in the visible and the mid-infrared. Free-electron laser is a versatile high-brilliance source of radiation in the latter spectral range. In this contribution, we briefly review some of the results obtained recently by the two-color spectroscopy with a free-electron laser in different semiconductors optically doped with rare earth and transition metal ions. Effects leading to both enhancement and quenching of emission from optical dopants will be presented. For InP:Yb, Si:Er, and Si:Cu activation of particular optically induced non-radiative recombination paths will be shown. For Si:Er and Si:Ag, observation of a low temperature optical memory effect will be reported

  19. Quantitative near-infrared spectroscopy on patients with peripheral vascular disease

    OpenAIRE

    Franceschini, MA; Fantini, S; Palumbo, R; Pasqualini, L; Vaudo, G; Franceschini, E; Gratton, E; Palumbo, B; Innocente, S; Mannarino, E

    1997-01-01

    We have used near-infrared spectroscopy to measure the hemoglobin saturation at rest and during exercise on patients affected by peripheral vascular disease (PVD). The instrument used in our study is a frequency-domain tissue oximeter which employs intensity modulated (110 MHz) laser diodes. We examined 9 subjects, 3 of which were controls and 6 were patients affected by stage II PVD. The optical probe was located on the calf muscle of the subjects. The measurement protocol consisted of: (1) ...

  20. Advances in near-infrared measurements

    CERN Document Server

    Patonay, Gabor

    1991-01-01

    Advances in Near-Infrared Measurements, Volume 1 provides an overview of near-infrared spectroscopy. The book is comprised of six chapters that tackle various areas of near-infrared measurement. Chapter 1 discusses remote monitoring techniques in near-infrared spectroscopy with an emphasis on fiber optics. Chapter 2 covers the applications of fibers using Raman techniques, and Chapter 3 tackles the difficulties associated with near-infrared data analysis. The subsequent chapters present examples of the capabilities of near-infrared spectroscopy from various research groups. The text wi

  1. Periodic array-based substrates for surface-enhanced infrared spectroscopy

    Science.gov (United States)

    Mayerhöfer, Thomas G.; Popp, Jürgen

    2018-01-01

    At the beginning of the 1980s, the first reports of surface-enhanced infrared spectroscopy (SEIRS) surfaced. Probably due to signal-enhancement factors of only 101 to 103, which are modest compared to those of surface-enhanced Raman spectroscopy (SERS), SEIRS did not reach the same significance up to date. However, taking the compared to Raman scattering much larger cross-sections of infrared absorptions and the enhancement factors together, SEIRS reaches about the same sensitivity for molecular species on a surface in terms of the cross-sections as SERS and, due to the complementary nature of both techniques, can valuably augment information gained by SERS. For the first 20 years since its discovery, SEIRS relied completely on metal island films, fabricated by either vapor or electrochemical deposition. The resulting films showed a strong variance concerning their structure, which was essentially random. Therefore, the increase in the corresponding signal-enhancement factors of these structures stagnated in the last years. In the very same years, however, the development of periodic array-based substrates helped SEIRS to gather momentum. This development was supported by technological progress concerning electromagnetic field solvers, which help to understand plasmonic properties and allow targeted design. In addition, the strong progress concerning modern fabrication methods allowed to implement these designs into practice. The aim of this contribution is to critically review the development of these engineered surfaces for SEIRS, to compare the different approaches with regard to their performance where possible, and report further gain of knowledge around and in relation to these structures.

  2. 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

  3. Cerebral near infrared spectroscopy oximetry in extremely preterm infants : Phase II randomised clinical trial

    NARCIS (Netherlands)

    Hyttel-Sorensen, Simon; Pellicer, Adelina; Alderliesten, Thomas; Austin, Topun; Van Bel, Frank; Benders, Manon; Claris, Olivier; Dempsey, Eugene; Franz, Axel R.; Fumagalli, Monica; Gluud, Christian; Grevstad, Berit; Hagmann, Cornelia; Lemmers, Petra; Van Oeveren, Wim; Pichler, Gerhard; Plomgaard, Anne Mette; Riera, Joan; Sanchez, Laura; Winkel, Per; Wolf, Martin; Greisen, Gorm

    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 units in

  4. Infrared spectroscopy and density functional theory investigation of calcite, chalk, and coccoliths-do we observe the mineral surface?

    DEFF Research Database (Denmark)

    Andersson, Martin Peter; Hem, Caroline Piper; Schultz, Logan Nicholas

    2014-01-01

    broadening from macroscopic dielectric effects. We detect water adsorbed on the high surface area synthetic calcite, which permits observation of the chemistry of thin liquid films on calcite using transmission infrared spectroscopy. The combination of infrared spectroscopy and density functional theory also...... asymmetric for the coccoliths and the synthetic calcite prepared using the carbonation method. It can be very well fitted by two peaks: a narrow Lorenzian at lower frequency and a broader Gaussian at higher frequency. These two samples both have a high specific surface area. Density functional theory...

  5. Absorption Spectroscopy in Hollow-Glass Waveguides Using Infrared Diode Lasers[4817-25

    International Nuclear Information System (INIS)

    Blake, Thomas A.; Kelly, James F.; Stewart, Timothy L.; Hartman, John S.; Sharpe, Steven W.; Sams, Robert L.; Alan Fried

    2002-01-01

    Near- and mid-infrared diode lasers combined with flexible, hollow waveguides hold the promise of light weight, field portable, fast response gas sensors. The advantages of using the waveguides compared to White or Herriott multireflection cells include a small gas volume, a high photon fill factor in the waveguide, which increases molecule-light interactions, and reduction or elimination of optical fringing, which usually sets the practical limit of detectivity in absorption spectroscopy. Though hollow waveguides have been commercially available for several years, relatively few results have been reported in the literature. We present here results from our laboratory where we have injected infrared laser light into straight and coiled lengths of hollow waveguides and performed direct and wavelength modulated absorption spectroscopy on nitrous oxide, ethylene, and nitric oxide. Using a 1 mm bore, 3 meter long coiled waveguide coated for the near infrared, nitrous oxide transitions near 6595 cm-1 were observed under flowing conditions. Signal-to-noise ratios on the order of 1500:1 with RMS noise equal to 2 X 10-5 were measured. In the mid-infrared light from either a 10.1 or 5.3 micron lead salt diode laser was injected into a three meter length of 1 mm bore hollow waveguide coated for the mid-infrared. The waveguide was coiled with one loop at a diameter of 52 cm. Ethylene transitions were observed in the vicinity of 985 cm-1 with a static fill of 0.2 Torr of pure ethylene in the waveguide and nitric oxide transitions were observed in the vicinity of 1906 cm-1 using either a flow or a static fill of 1 ppm NO in nitrogen. In direct absorption the NO transitions are observed to have a signal-to-noise of approximately 5:1 for transitions with absorbances on the order of 10-3. Using wavelength modulated techniques the signal-to-noise ratio improves at least an order of magnitude. These encouraging results indicate that waveguides can be used for in situ gas monitoring

  6. Mid-infrared and near-infrared spectroscopy for rapid detection of Gardeniae Fructus by a liquid-liquid extraction process.

    Science.gov (United States)

    Tao, Lingyan; Lin, Zhonglin; Chen, Jiashan; Wu, Yongjiang; Liu, Xuesong

    2017-10-25

    Gardeniae Fructus is widely used in the pharmaceutical industry, and many studies have confirmed its medical and economic value. In this study, samples collected from different liquid-liquid extraction batches of Gardeniae Fructus were detected by mid-infrared (MIR) and near-infrared (NIR) spectroscopy. Seven analytes, neochlorogenic acid (5-CQA), cryptochlorogenic acid (4-CQA), chlorogenic acid (3-CQA), geniposidic acid (GEA), deacetyl-asperulosidic acid methyl ester (DAAME), genipin-gentiobioside (GGB), and gardenoside (GA), were chosen as quality property indexes of Gardeniae Fructus. The two kinds of spectra were each used to build models by single partial least squares (PLS). Additionally, both spectral data were combined and modeled by multiblock PLS. For single spectroscopy modeling results, NIR had a better prediction for high-concentration analytes (3-CQA, DAAME, GGB, and GA) whereas MIR performed better for low-concentration analytes (5-CQA, 4-CQA, and GEA). The multiblock methodology was found to be better compared to single spectroscopy models for all seven analytes. Specifically, the coefficients of determination (R 2 ) of the NIR, MIR, and multiblock PLS calibration models of all seven components were higher than 0.95. Relative standard errors of prediction (RSEP) were all less than 7%, except for models of GGB, which were 10.36%, 13.24%, and 8.15% for the NIR-PLS, MIR-PLS, and multiblock models, respectively. These results indicate that MIR and NIR spectrographic techniques could provide a new choice for quality control in industrial production of Gardeniae Fructus. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Infrared spectroscopy and thermal analysis of prepared cation exchangers from cellulosic materials

    International Nuclear Information System (INIS)

    Nada, A.M.A.; EI-Sherief, S.; Nasr, A.; Kamel, M.

    2005-01-01

    Different cation exchangers were prepared by incorporation of phosphate and sulfate groups into acid or alkali treated wood pulp. The molecular structure of these cation exchangers were followed by infrared spectroscopy and thermal degradation analysis technique. From infrared spectra, a new bands are seen at 1200 and 980 cm-1 in phosphorylated wood pulp due to the formation of C-O-P bond. Another bands were seen at 1400, 1200 and 980 cm-1 in phospho sulfonated wood pulp due to the formation of CO- P and C-O-S bonds. Also, it is seen from infrared spectra that the crystallinity index for acid treated wood pulp has a higher value than untreated and alkali treated wood pulp. On the other hand, the acid treated and phosphorylated acid treated wood pulp have a higher activation energy than untreated and phosphorylated alkali treated wood pulp

  8. 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.

  9. Metal ion induced room temperature phase transformation and stimulated infrared spectroscopy on TiO2-based surfaces

    International Nuclear Information System (INIS)

    Gole, James L.; Prokes, S.M.; White, Mark G.

    2008-01-01

    Raman and infrared spectroscopy are used to demonstrate (1) the high spin metal ion induced room temperature transformation of anatase to rutile TiO 2 and (2) the phenomena of stimulated IR spectroscopy induced by simultaneous nitrogen doping and high spin metal ion seeding of a TiO 2 nanocolloid lattice

  10. Study of cancer cell lines with Fourier transform infrared (FTIR)/vibrational absorption (VA) spectroscopy

    DEFF Research Database (Denmark)

    Uceda Otero, E. P.; Eliel, G. S. N.; Fonseca, E. J. S.

    2013-01-01

    In this work we have used Fourier transform infrared (FTIR) / vibrational absorption (VA) spectroscopy to study two cancer cell lines: the Henrietta Lacks (HeLa) human cervix carcinoma and 5637 human bladder carcinoma cell lines. Our goal is to experimentally investigate biochemical changes...

  11. Quantification of changes in skin hydration and sebum after tape stripping using infrared spectroscopy

    Science.gov (United States)

    Ezerskaia, A.; Pereira, S. F.; Urbach, H. P.; Varghese, B.

    2017-02-01

    Skin barrier function relies on well balanced water and lipid system of stratum corneum. Optimal hydration and oiliness levels are indicators of skin health and integrity. We demonstrate an accurate and sensitive depth profiling of stratum corneum sebum and hydration levels using short wave infrared spectroscopy in the spectral range around 1720 nm. We demonstrate that short wave infrared spectroscopic technique combined with tape stripping can provide morequantitative and more reliable skin barrier function information in the low hydration regime, compared to conventional biophysical methods.

  12. 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...

  13. 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.

  14. Ischemia monitoring in off-pump coronary artery bypass surgery using intravascular near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Zerkowski Hans-Reinhard

    2006-05-01

    Full Text Available Abstract Background In off-pump coronary artery bypass surgery, manipulations on the beating heart can lead to transient interruptions of myocardial oxygen supply, which can generate an accumulation of oxygen-dependent metabolites in coronary venous blood. The objective of this study was to evaluate the reliability of intravascular near-infrared spectroscopy as a monitoring method to detect possible ischemic events in off-pump coronary artery bypass procedures. Methods In 15 elective patients undergoing off-pump myocardial revascularization, intravascular near-infrared spectroscopic analysis of coronary venous blood was performed. NIR signals were transferred through a fiberoptic catheter for signal emission and collection. For data analysis and processing, a miniature spectrophotometer with multivariate statistical package was used. Signal acquisition and analysis were performed before and after revascularization. Spectroscopic data were compared with hemodynamic parameters, electrocardiogram, transesophageal echocardiography and laboratory findings. Results A conversion to extracorporeal circulation was not necessary. The mean number of grafts per patient was 3.1 ± 0.6. An intraoperative myocardial ischemia was not evident, as indicated by electrocardiogram and transesophageal echocardiography. Continuous spectroscopic analysis showed reproducible absorption spectra of coronary sinus blood. Due to uneventful intraoperative courses, clear ischemia-related changes could be detected in none of the patients. Conclusion Our initial results show that intravascular near-infrared spectroscopy can reliably be used for an online intraoperative ischemia monitoring in off-pump coronary artery bypass surgery. However, the method has to be further evaluated and standardized to determine the role of spectroscopy in off-pump coronary artery bypass surgery.

  15. Remote characterization of mixed waste by infrared spectroscopy: Fiscal year 1995 report

    International Nuclear Information System (INIS)

    Rebagay, T.V.; Reich, F.R.; Dodd, D.A.; Lopez, T.; Watts, J.K.; Cash, R.J.

    1995-09-01

    This report summarizes development work completed in FY 1995 on near-infrared (NIR) and Fourier Transform Infrared (FTIR) spectroscopy of determining the moisture content and solid species present in Hanford Site high-level waste. In prior fiscal years, the main emphasis was on identification of cyanide species that might be present in the ferrocyanide waste tanks, but the present thrust has been more focused on determining the moisture content of the waste. If sufficient moisture is present in the waste, propagating reactions in reactive waste are precluded, regardless of its fuel content. A prototype hot cell NIR moisture probe is now ready for hot cell deployment to sense moisture contents and homogeneity in tank waste samples

  16. Near-infrared spectroscopy determined cerebral oxygenation with eliminated skin blood flow in young males

    DEFF Research Database (Denmark)

    Hirasawa, Ai; Kaneko, Takahito; Tanaka, Naoki

    2016-01-01

    We estimated cerebral oxygenation during handgrip exercise and a cognitive task using an algorithm that eliminates the influence of skin blood flow (SkBF) on the near-infrared spectroscopy (NIRS) signal. The algorithm involves a subtraction method to develop a correction factor for each subject. ...

  17. 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.

  18. Infrared Absorption Spectroscopy and Chemical Kinetics of Free Radicals. Final Performance Report, August 1, 1985--July 31, 1994

    Science.gov (United States)

    Curl, R. F.; Glass, G. P.

    1995-06-01

    This research was directed at the detection, monitoring, and study (by infrared absorption spectroscopy) of the chemical kinetic behavior of small free radical species thought to be important intermediates in combustion. The work typically progressed from the detection and analysis of the infrared spectrum of combustion radical to the utilization of the infrared spectrum thus obtained in the investigation of chemical kinetics of the radical species. The methodology employed was infrared kinetic spectroscopy. In this technique the radical is produced by UV flash photolysis using an excimer laser and then its transient infrared absorption is observed using a single frequency cw laser as the source of the infrared probe light. When the probe laser frequency is near the center of an absorption line of the radical produced by the flash, the transient infrared absorption rises rapidly and then decays as the radical reacts with the precursor or with substances introduced for the purpose of studying the reaction kinetics or with itself. The decay times observed in these studies varied from less than one microsecond to more than one millisecond. By choosing appropriate time windows after the flash and the average infrared detector signal in a window as data channels, the infrared spectrum of the radical may be obtained. By locking the infrared probe laser to the center of the absorption line and measuring the rate of decay of the transient infrared absorption signal as the chemical composition of the gas mixture is varied, the chemical kinetics of the radical may be investigated. In what follows the systems investigated and the results obtained are outlined.

  19. APPLICATION OF NEAR INFRARED SPECTROSCOPY AND EXPLORATORY DATA ANALYSIS FOR THE IDENTIFICATION OF WOODS IN THE FURNITURE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Lucas Ferreira Bastos

    2012-07-01

    Full Text Available The paper aimed to investigate the application of infrared spectroscopy and exploratory data analysis to distinguish the different types of natural woods, contributing to the control of the origin of the materials used in the furniture industry. The near infrared spectroscopy (NIR was used for the characterization of 44 samples of 19 different types of wood, and the principal component analysis (PCA to discriminate. The proposed methodology was efficient in the separation of some samples, but further studies should be performed for the diffusion of this methodology in the routine of the furniture industry.

  20. Atmospheric and surface properties of Mars obtained by infrared spectroscopy on Mariner 9

    Science.gov (United States)

    Conrath, B.; Curran, R.; Hanel, R.; Kunde, V.; Maguire, W.; Pearl, J.; Pirraglia, J.; Welker, J.; Burke, T.

    1973-01-01

    The infrared spectroscopy experiment on Mariner 9 obtained data over much of Mars. Interpretation of the thermal emission of Mars in terms of atmospheric temperatures, wind fields and dynamics, surface temperatures, surface pressure and topography, mineral composition, and minor atmospheric constituents including isotopic ratios, as well as a search for unexpected phenomena are reported.

  1. Infrared Multiphoton Dissociation Spectroscopy with Free-Electron Lasers: On the Road from Small Molecules to Biomolecules.

    Science.gov (United States)

    Jašíková, Lucie; Roithová, Jana

    2018-03-07

    Infrared multiphoton dissociation (IRMPD) spectroscopy is commonly used to determine the structure of isolated, mass-selected ions in the gas phase. This method has been widely used since it became available at free-electron laser (FEL) user facilities. Thus, in this Minireview, we examine the use of IRMPD/FEL spectroscopy for investigating ions derived from small molecules, metal complexes, organometallic compounds and biorelevant ions. Furthermore, we outline new applications of IRMPD spectroscopy to study biomolecules. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Infrared micro-spectroscopy of human tissue: principles and future promises.

    Science.gov (United States)

    Diem, Max; Ergin, Ayşegül; Remiszewski, Stan; Mu, Xinying; Akalin, Ali; Raz, Dan

    2016-06-23

    This article summarizes the methods employed, and the progress achieved over the past two decades in applying vibrational (Raman and IR) micro-spectroscopy to problems of medical diagnostics and cellular biology. During this time, several research groups have verified the enormous information contained in vibrational spectra; in fact, information on protein, lipid and metabolic composition of cells and tissues can be deduced by decoding the observed vibrational spectra. This decoding process is aided by the availability of computer workstations and advanced algorithms for data analysis. Furthermore, commercial instrumentation for the fast collection of both Raman and infrared micro-spectral data has enabled the collection of images of cells and tissues based solely on vibrational spectroscopic data. The progress in the field has been manifested by a steady increase in the number and quality of publications submitted by established and new research groups in vibrational spectroscopy in the biological and biomedical arenas.

  3. 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.

  4. 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.

  5. 7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. 801.7 Section 801.7 Agriculture Regulations of the Department of Agriculture...), DEPARTMENT OF AGRICULTURE OFFICIAL PERFORMANCE REQUIREMENTS FOR GRAIN INSPECTION EQUIPMENT § 801.7 Reference...

  6. 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...

  7. Noninvasive detection of change in skeletal muscle oxygenation during incremental exercise with near-infrared spectroscopy

    Science.gov (United States)

    Liu, Fang; Luo, Qingming; Xu, Guodong; Li, Pengcheng

    2003-12-01

    Near infrared spectroscopy (NIRS) has been developed as a non-invasive method to assess O2 delivery, O2 consumption and blood flow, in diverse local muscle groups at rest and during exercise. The aim of this study was to investigate local O2 consumption in exercising muscle by use of near-infrared spectroscopy (NIRS). Ten elite athletes of different sport items were tested in rest and during step incremental load exercise. Local variations of quadriceps muscles were investigated with our wireless NIRS blood oxygen monitor system. The results show that the changes of blood oxygen relate on the sport items, type of muscle, kinetic capacity et al. These results indicate that NIRS is a potential useful tool to detect local muscle oxygenation and blood flow profiles; therefore it might be easily applied for evaluating the effect of athletes training.

  8. 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.

  9. Identification of Chinese medicinal fungus Cordyceps sinensis by depth-profiling mid-infrared photoacoustic spectroscopy

    Science.gov (United States)

    Du, Changwen; Zhou, Jianmin; Liu, Jianfeng

    2017-02-01

    With increased demand for Cordyceps sinensis it needs rapid methods to meet the challenge of identification raised in quality control. In this study Cordyceps sinensis from four typical natural habitats in China was characterized by depth-profiling Fourier transform infrared photoacoustic spectroscopy. Results demonstrated that Cordyceps sinensis samples resulted in typical photoacoustic spectral appearance, but heterogeneity was sensed in the whole sample; due to the heterogeneity Cordyceps sinensis was represented by spectra of four groups including head, body, tail and leaf under a moving mirror velocity of 0.30 cm s- 1. The spectra of the four groups were used as input of a probabilistic neural network (PNN) to identify the source of Cordyceps sinensis, and all the samples were correctly identified by the PNN model. Therefore, depth-profiling Fourier transform infrared photoacoustic spectroscopy provides novel and unique technique to identify Cordyceps sinensis, which shows great potential in quality control of Cordyceps sinensis.

  10. Geographical traceability of Marsdenia tenacissima by Fourier transform infrared spectroscopy and chemometrics

    Science.gov (United States)

    Li, Chao; Yang, Sheng-Chao; Guo, Qiao-Sheng; Zheng, Kai-Yan; Wang, Ping-Li; Meng, Zhen-Gui

    2016-01-01

    A combination of Fourier transform infrared spectroscopy with chemometrics tools provided an approach for studying Marsdenia tenacissima according to its geographical origin. A total of 128 M. tenacissima samples from four provinces in China were analyzed with FTIR spectroscopy. Six pattern recognition methods were used to construct the discrimination models: support vector machine-genetic algorithms, support vector machine-particle swarm optimization, K-nearest neighbors, radial basis function neural network, random forest and support vector machine-grid search. Experimental results showed that K-nearest neighbors was superior to other mathematical algorithms after data were preprocessed with wavelet de-noising, with a discrimination rate of 100% in both the training and prediction sets. This study demonstrated that FTIR spectroscopy coupled with K-nearest neighbors could be successfully applied to determine the geographical origins of M. tenacissima samples, thereby providing reliable authentication in a rapid, cheap and noninvasive way.

  11. 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

  12. [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.

  13. 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...

  14. Combined optimal-pathlengths method for near-infrared spectroscopy analysis

    International Nuclear Information System (INIS)

    Liu Rong; Xu Kexin; Lu Yanhui; Sun Huili

    2004-01-01

    Near-infrared (NIR) spectroscopy is a rapid, reagent-less and nondestructive analytical technique, which is being increasingly employed for quantitative application in chemistry, pharmaceutics and food industry, and for the optical analysis of biological tissue. The performance of NIR technology greatly depends on the abilities to control and acquire data from the instrument and to calibrate and analyse data. Optical pathlength is a key parameter of the NIR instrument, which has been thoroughly discussed in univariate quantitative analysis in the presence of photometric errors. Although multiple wavelengths can provide more chemical information, it is difficult to determine a single pathlength that is suitable for each wavelength region. A theoretical investigation of a selection procedure for multiple pathlengths, called the combined optimal-pathlengths (COP) method, is identified in this paper and an extensive comparison with the single pathlength method is also performed on simulated and experimental NIR spectral data sets. The results obtained show that the COP method can greatly improve the prediction accuracy in NIR spectroscopy quantitative analysis

  15. 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)

  16. 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.

  17. 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

  18. 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

  19. Surface reactions during atomic layer deposition of Pt derived from gas phase infrared spectroscopy

    NARCIS (Netherlands)

    Kessels, W.M.M.; Knoops, H.C.M.; Dielissen, S.A.F.; Mackus, A.J.M.; Sanden, van de M.C.M.

    2009-01-01

    Infrared spectroscopy was used to obtain absolute number information on the reaction products during atomic layer deposition of Pt from (methylcyclopentadienyl)trimethylplatinum [(MeCp)PtMe3] and O2. From the detection of CO2 and H2O it was established that the precursor ligands are oxidatively

  20. The infrared spectroscopy in the study of the bone crystallinity thermally affected

    International Nuclear Information System (INIS)

    Medina, C.; Tiesler, V.; Azamar, J.A.; Alvarado G, J.J.; Quintana, P.

    2006-01-01

    Bone is made up by both organic and inorganic components. Among the latter stands out hydroxyapatite (HAP), composed by hexagonal crystallites arranged in a laminar form. The size of the hydroxyapatite crystals may be altered by different conditions, among those figures thermal exhibition, since during burning the bone eliminates organic matrix and thus promotes the crystallization process of the material. An experimental series was designed to measure crystallinity, in which pig bone remains were burnt at different temperatures and analyzed by infrared spectroscopy (FTIR). By means of analogy a comparison was made between the infrared spectra in order to compare with the ones obtained from the archaeological samples, coming from the Classic period Maya sites of Calakmul and Becan, Campeche. (Author)

  1. Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers.

    Science.gov (United States)

    Jones, Ben; Parry, Dave; Cooper, Chris E

    2018-01-01

    The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis . uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming.

  2. 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.

  3. Fabrication of calix[4]pyrrole nanofilms at the glassy carbon surface and their characterization by spectroscopic, optic and electrochemical methods

    International Nuclear Information System (INIS)

    Taner, Bilge; Ozcan, Emine; Ustuendag, Zafer; Keskin, Selda; Solak, Ali Osman; Eksi, Haslet

    2010-01-01

    meso-Octamethylcalix[4]pyrrole (CP) and meso-heptaethylcalix[4]pyrrole-meso-4-aminophenyl (4APCP) modified glassy carbon (GC) electrodes were prepared by the electrochemical oxidation in acetonitrile solution. Binding of the calix[4]pyrroles with the glassy carbon surface was investigated that it is through the etheric linkage revealed from the reflection-absorption infrared spectroscopy (RAIRS). Surface films of CP and 4APCP were investigated by cyclic voltammetry (CV), ellipsometry, X-ray photoelectron spectroscopy, RAIRS and the contact angle measurements. The thicknesses of the films were determined by ellipsometry which confirmed that the film was multilayer and homogeneous over the surface. Ellipsometric measurements also provided that the CP and 4APCP film thicknesses were 2.49 nm and 4.58 nm for 6 CV cycle modification, corresponding to 66 μF/cm 2 and 106 μF/cm 2 capacitances obtained by CV. The wetting behavior was examined by contact angle measurements and found that the hydrophobicity of the GC-4APCP surface was higher than that of GC-CP, probably due to the aromatic meso substituent present in the former.

  4. Dissociation of trimethylgallium on the ZrB{sub 2}(0001) surface

    Energy Technology Data Exchange (ETDEWEB)

    Manandhar, Kedar; Trenary, Michael [Department of Chemistry, University of Illinois at Chicago, 845W Taylor St., Chicago, Illinois 60607 (United States); Otani, Shigeki [National Institute for Material Science, 1-1 Namiki, Tsukuba-shi, Ibaraki 305-0044 (Japan); Zapol, Peter [Materials Science Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439 (United States)

    2013-11-15

    X-ray photoelectron spectroscopy and reflection absorption infrared spectroscopy (RAIRS) have been used to study the dissociative adsorption of trimethylgallium (TMG) on the ZrB{sub 2}(0001) surface. Spectra were obtained as a function of annealing temperature following TMG exposure at temperatures of 95 and 300 K, and also as a function of TMG exposure for a surface temperature of 300 K. After annealing above 220 K, a significant decrease in the relative concentration of carbon and gallium occurred accompanied by a shift of ∼0.2 eV in the Ga 2p{sub 3/2} binding energy. The RAIR spectra show that after annealing to ∼220 K, only one CH{sub 3} deformation band at 1196 cm{sup −1} remains, the intensity of which is considerably decreased indicating loss of at least one methyl group from TMG. Further annealing leads to the sequential loss of the other methyl groups. The first methyl desorbs while the last two dissociate to deposit two C atoms per TMG molecule onto the ZrB{sub 2} surface.

  5. Dissociation of trimethylgallium on the ZrB2(0001) surface

    International Nuclear Information System (INIS)

    Manandhar, Kedar; Trenary, Michael; Otani, Shigeki; Zapol, Peter

    2013-01-01

    X-ray photoelectron spectroscopy and reflection absorption infrared spectroscopy (RAIRS) have been used to study the dissociative adsorption of trimethylgallium (TMG) on the ZrB 2 (0001) surface. Spectra were obtained as a function of annealing temperature following TMG exposure at temperatures of 95 and 300 K, and also as a function of TMG exposure for a surface temperature of 300 K. After annealing above 220 K, a significant decrease in the relative concentration of carbon and gallium occurred accompanied by a shift of ∼0.2 eV in the Ga 2p 3/2 binding energy. The RAIR spectra show that after annealing to ∼220 K, only one CH 3 deformation band at 1196 cm −1 remains, the intensity of which is considerably decreased indicating loss of at least one methyl group from TMG. Further annealing leads to the sequential loss of the other methyl groups. The first methyl desorbs while the last two dissociate to deposit two C atoms per TMG molecule onto the ZrB 2 surface

  6. Infrared and infrared emission spectroscopic study of typical Chinese kaolinite and halloysite.

    Science.gov (United States)

    Cheng, Hongfei; Frost, Ray L; Yang, Jing; Liu, Qinfu; He, Junkai

    2010-12-01

    The structure and thermal stability between typical Chinese kaolinite and halloysite were analysed by X-ray diffraction (XRD), infrared spectroscopy, infrared emission spectroscopy (IES) and Raman spectroscopy. Infrared emission spectroscopy over the temperature range of 300-700°C has been used to characterise the thermal decomposition of both kaolinite and halloysite. Halloysite is characterised by two bands in the water bending region at 1629 and 1648 cm(-1), attributed to structural water and coordinated water in the interlayer. Well defined hydroxyl stretching bands at around 3695, 3679, 3652 and 3625 cm(-1) are observed for both kaolinite and halloysite. The 550°C infrared emission spectrum of halloysite is similar to that of kaolinite in 650-1350 cm(-1) spectral region. The infrared emission spectra of halloysite were found to be considerably different to that of kaolinite at lower temperatures. These differences are attributed to the fundamental difference in the structure of the two minerals. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Comparison of cortical activation in an upper limb added-purpose task versus a single-purpose task: a near-infrared spectroscopy study

    OpenAIRE

    Huang, Fubiao; Hirano, Daisuke; Shi, Yun; Taniguchi, Takamichi

    2015-01-01

    [Purpose] The purpose of this study was to compare prefrontal activations during an added-purpose task with those during a single-purpose task using functional near-infrared spectroscopy. [Subjects] Six healthy right-handed adults were included in this study. [Methods] The participants were instructed to complete both added-purpose and single-purpose activities separately with each hand. The near-infrared spectroscopy probes were placed on the scalp overlying the prefrontal cortex, according ...

  8. Moessbauer and infrared spectroscopy as a diagnostic tool for the characterization of ferric tannates

    Energy Technology Data Exchange (ETDEWEB)

    Jaen, Juan A., E-mail: jjaen@ancon.up.ac.p [Universidad de Panama, Depto. de Quimica Fisica, CITEN, Lab. No. 105, Edificio de Laboratorios Cientificos-VIP (Panama); Navarro, Cesar [Universidad de Panama, Escuela de Quimica, Facultad de Ciencias Naturales, Exactas y Tecnologia (Panama)

    2009-07-15

    Fourier transform infrared spectroscopy and Moessbauer spectroscopy are use for the characterization and qualitative analysis of hydrolysable and condensed tannates. The two classes of tannates may be differentiated from the characteristic IR pattern. Moessbauer proof that a mixture of mono- and bis-type ferric tannate complexes, and an iron(II)-tannin complex are obtained from the interaction of hydrolysable tannins (tannic acid and chestnut tannin) and condensed tannins (mimosa and quebracho) with a ferric nitrate solution. At pH 7, a partially hydrolyzed ferric tannate complex was also obtained.

  9. 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.

  10. Moessbauer and infrared spectroscopy as a diagnostic tool for the characterization of ferric tannates

    International Nuclear Information System (INIS)

    Jaen, Juan A.; Navarro, Cesar

    2009-01-01

    Fourier transform infrared spectroscopy and Moessbauer spectroscopy are use for the characterization and qualitative analysis of hydrolysable and condensed tannates. The two classes of tannates may be differentiated from the characteristic IR pattern. Moessbauer proof that a mixture of mono- and bis-type ferric tannate complexes, and an iron(II)-tannin complex are obtained from the interaction of hydrolysable tannins (tannic acid and chestnut tannin) and condensed tannins (mimosa and quebracho) with a ferric nitrate solution. At pH 7, a partially hydrolyzed ferric tannate complex was also obtained.

  11. ATR and transmission analysis of pigments by means of far infrared spectroscopy.

    Science.gov (United States)

    Kendix, Elsebeth L; Prati, Silvia; Joseph, Edith; Sciutto, Giorgia; Mazzeo, Rocco

    2009-06-01

    In the field of FTIR spectroscopy, the far infrared (FIR) spectral region has been so far less investigated than the mid-infrared (MIR), even though it presents great advantages in the characterization of those inorganic compounds, which are inactive in the MIR, such as some art pigments, corrosion products, etc. Furthermore, FIR spectroscopy is complementary to Raman spectroscopy if the fluorescence effects caused by the latter analytical technique are considered. In this paper, ATR in the FIR region is proposed as an alternative method to transmission for the analyses of pigments. This methodology was selected in order to reduce the sample amount needed for analysis, which is a must when examining cultural heritage materials. A selection of pigments have been analyzed in both ATR and transmission mode, and the resulting spectra were compared with each other. To better perform this comparison, an evaluation of the possible effect induced by the thermal treatment needed for the preparation of the polyethylene pellets on the transmission spectra of the samples has been carried out. Therefore, pigments have been analyzed in ATR mode before and after heating them at the same temperature employed for the polyethylene pellet preparation. The results showed that while the heating treatment causes only small changes in the intensity of some bands, the ATR spectra were characterized by differences in both intensity and band shifts towards lower frequencies if compared with those recorded in transmission mode. All pigments' transmission and ATR spectra are presented and discussed, and the ATR method was validated on a real case study.

  12. Evaluation of ionizing radiation effects on recycled polyamide-6 by infrared spectroscopy and measures of fluidity index

    International Nuclear Information System (INIS)

    Evora, Maria Cecilia; Goncalez, Odair Lelis

    2000-01-01

    In this work are presented partial results from a set of experiments and analyses performed at CTA and IPEN laboratories for the characterization of the polyamide-6, recycled and irradiated with a 1.5 MeV electron beam with a 500 kGy dose. The experimental determinations were carried out using infrared spectroscopy with Fourier transform (FTIR), in the medium infrared region (MIR) and in the far infrared region (FAR), to evaluate if exist significant changes in the infrared absorption region of the amide groups due to the polyamide irradiation. Characteristics relative to the measured fluidity index were used to evaluate the irradiated material crosslinking. (author)

  13. Application of mid-infrared tuneable diode laser absorption spectroscopy to plasma diagnostics: a review

    International Nuclear Information System (INIS)

    Roepcke, J; Lombardi, G; Rousseau, A; Davies, P B

    2006-01-01

    Within the last decade mid-infrared absorption spectroscopy over a region from 3 to 17μm and based on tuneable lead salt diode lasers, often called tuneable diode laser absorption spectroscopy or TDLAS, has progressed considerably as a powerful diagnostic technique for in situ studies of the fundamental physics and chemistry in molecular plasmas. The increasing interest in processing plasmas containing hydrocarbons, fluorocarbons, organo-silicon and boron compounds has led to further applications of TDLAS because most of these compounds and their decomposition products are infrared active. TDLAS provides a means of determining the absolute concentrations of the ground states of stable and transient molecular species, which is of particular importance for the investigation of reaction kinetic phenomena. Information about gas temperature and population densities can also be derived from TDLAS measurements. A variety of free radicals and molecular ions have been detected by TDLAS. Since plasmas with molecular feed gases are used in many applications such as thin film deposition, semiconductor processing, surface activation and cleaning, and materials and waste treatment, this has stimulated the adaptation of infrared spectroscopic techniques to industrial requirements. The recent development of quantum cascade lasers (QCLs) offers an attractive new option for the monitoring and control of industrial plasma processes. The aim of the present paper is threefold: (i) to review recent achievements in our understanding of molecular phenomena in plasmas (ii) to report on selected studies of the spectroscopic properties and kinetic behaviour of radicals and (iii) to describe the current status of advanced instrumentation for TDLAS in the mid-infrared

  14. Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers

    OpenAIRE

    Ben Jones; Dave Parry; Chris E. Cooper

    2018-01-01

    The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repea...

  15. On the oxidation mechanism of microcrystalline silicon thin films studied by Fourier transform infrared spectroscopy

    NARCIS (Netherlands)

    Bronneberg, A. C.; Smets, A. H. M.; Creatore, M.; M. C. M. van de Sanden,

    2011-01-01

    Insight into the oxidation mechanism of microcrystalline silicon thin films has been obtained by means of Fourier transform infrared spectroscopy. The films were deposited by using the expanding thermal plasma and their oxidation upon air exposure was followed in time. Transmission spectra were

  16. Limitations and potential of spectral subtractions in fourier-transform infrared (FTIR) spectroscopy of soil samples

    Science.gov (United States)

    Soil science research is increasingly applying Fourier transform infrared (FTIR) spectroscopy for analysis of soil organic matter (SOM). However, the compositional complexity of soils and the dominance of the mineral component can limit spectroscopic resolution of SOM and other minor components. The...

  17. 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,

  18. New enhanced sensitivity infrared laser spectroscopy techniques applied to reactive plasmas and trace gas detection

    NARCIS (Netherlands)

    Welzel, S.

    2009-01-01

    Infrared laser absorption spectroscopy (IRLAS) employing both tuneable diode and quantum cascade lasers (TDLs, QCLs) has been applied with both high sensitivity and high time resolution to plasma diagnostics and trace gas measurements. TDLAS combined with a conventional White type multiple pass cell

  19. Intact neurovascular coupling during executive function in migraine without aura: interictal near-infrared spectroscopy study

    DEFF Research Database (Denmark)

    Schytz, H W; Ciftçi, K; Akin, A

    2010-01-01

    An altered neurovascular coupling has been proposed in migraine. We aimed to investigate neurovascular coupling during a mental task interictally in patients with migraine without aura (MO) by near-infrared spectroscopy (NIRS). Twelve migraineurs and 12 healthy controls were included. Using NIRS,...

  20. Application of near-infrared spectroscopy to predict microfibril angle of 14-year-old Pinus patula

    CSIR Research Space (South Africa)

    Zbonak, A

    2006-09-01

    Full Text Available An investigation was conducted to test the feasibility of near infrared spectroscopy (NIR) as a tool for predicting the microfibril angle (MFA) of solid wood samples of Pinus patula. Thirty 14 year-old trees were selected from three compartments...

  1. Nanocomposites of polypropylene and organophilic montmorillonite clay: X-ray diffraction, infrared spectroscopy with Fourier transform and water permeation

    International Nuclear Information System (INIS)

    Morelli, Fernanda C.; Ruvolo Filho, Adhemar

    2009-01-01

    In this work were prepared nanocomposites of polypropylene and organophilic montmorillonite Cloisite 20A with concentrations of 1.5%, 2.5%, 5.0% and 7.5% clay and graft polypropylene with maleic anhydride as compatibilizer. The mixture was made in the melt state using a twin screw extruder. The materials were characterized by x-ray diffraction, infrared spectroscopy with Fourier transform and analysis of water vapor permeation. The results of x-ray diffraction and infrared spectroscopy indicates the formation of nanocomposites with structures probably exfoliate and / or intercalated for concentrations of 1.5% and 2.5% clay, and provided a marked decrease in the water permeability, corroborating with other analysis. (author)

  2. 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.

  3. Analysis of serum cortisol levels by Fourier Transform Infrared Spectroscopy for diagnosis of stress in athletes

    Directory of Open Access Journals (Sweden)

    Lia Campos Lemes

    Full Text Available Abstract Introduction Fourier-transform infrared (FT-IR spectroscopy is a technique with great potential for body fluids analyses. The aim of this study was to examine the impact of session training on cortisol concentrations in rugby players by means of infrared analysis of serum. Methods Blood collections were performed pre, post and 24 hours after of rugby training sessions. Serum cortisol was analyzed by FT-IR spectroscopy and chemiluminescent immunoassay. Results There was a significant difference between the integrated area, in the region of 1180-1102 cm-1, of the spectra for pre, post and post 24 h serums. The cortisol concentration obtained by chemiluminescent immunoassay showed no significant difference between pre, post and post 24 h. Positive correlations were obtained between the techniques (r = 0.75, post (r = 0.83 and post 24 h (r = 0.73. Conclusion The results showed no increase in cortisol levels of the players after the training sessions, as well as positive correlations indicating that FT-IR spectroscopy have produced promising results for the analysis of serum for diagnosis of stress.

  4. Metal ion induced room temperature phase transformation and stimulated infrared spectroscopy on TiO{sub 2}-based surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gole, James L. [Schools of Physics and Mechanical Engineering, Georgia Institute of Technology, 837 State Street, Atlanta, GA 30332-0430 (United States)], E-mail: jim.gole@physics.gatech.edu; Prokes, S.M. [Code 6876, NRL, Washington, DC 20375 (United States)], E-mail: prokes@estd.nrl.navy.mil; White, Mark G. [Dave C. Swalm School of Chemical Engineering, James Worth Bagley College of Engineering, Box 959, MS 39762 (United States)], E-mail: white@che.msstate.edu

    2008-11-30

    Raman and infrared spectroscopy are used to demonstrate (1) the high spin metal ion induced room temperature transformation of anatase to rutile TiO{sub 2} and (2) the phenomena of stimulated IR spectroscopy induced by simultaneous nitrogen doping and high spin metal ion seeding of a TiO{sub 2} nanocolloid lattice.

  5. 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

  6. Design of high-efficiency diffractive optical elements towards ultrafast mid-infrared time-stretched imaging and spectroscopy

    Science.gov (United States)

    Xie, Hongbo; Ren, Delun; Wang, Chao; Mao, Chensheng; Yang, Lei

    2018-02-01

    Ultrafast time stretch imaging offers unprecedented imaging speed and enables new discoveries in scientific research and engineering. One challenge in exploiting time stretch imaging in mid-infrared is the lack of high-quality diffractive optical elements (DOEs), which encode the image information into mid-infrared optical spectrum. This work reports the design and optimization of mid-infrared DOE with high diffraction-efficiency, broad bandwidth and large field of view. Using various typical materials with their refractive indices ranging from 1.32 to 4.06 in ? mid-infrared band, diffraction efficiencies of single-layer and double-layer DOEs have been studied in different wavelength bands with different field of views. More importantly, by replacing the air gap of double-layer DOE with carefully selected optical materials, one optimized ? triple-layer DOE, with efficiency higher than 95% in the whole ? mid-infrared window and field of view greater than ?, is designed and analyzed. This new DOE device holds great potential in ultrafast mid-infrared time stretch imaging and spectroscopy.

  7. Entre itinéraires et trajets : représentations des déplacements dans les guides de voyage au tournant du XIXe siècle

    Directory of Open Access Journals (Sweden)

    Ariane Devanthéry

    2011-06-01

    Full Text Available Un itinéraire est plus qu’une route : c’est une route sélectionnée, choisie par une époque et jalonnée de savoirs, de devoirs et d’émotions. Le Grand Tour ayant connu des itinéraires fortement codés, comment se fait le passage au tourisme ? En douceur ou avec fracas ? Y a-t-il alors abandon de tout itinéraire, invention de nouveaux cheminements ou redéfinition ? Et si la transformation du Grand Tour en tourisme se jouait aussi dans les manières de mettre en scène l’espace des voyages ?An itinerary is more than a route: it is a selected route, chosen by a time and lined with knowledge and emotions. As the Grand Tour had known some strongly coded itineraries, how does the transition to tourism happen? Smoothly or with a crash? Is then a giving up of all itineraries, new ways invented, or redefinition? And what if the Grand Tour converting into tourism was also been acted in the way of displaying the travelling space?

  8. 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

  9. Quantification of DNA in simple eukaryotic cells using Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Whelan, Donna R; Bambery, Keith R; Puskar, Ljiljana; McNaughton, Don; Wood, Bayden R

    2013-10-01

    A technique capable of detecting and monitoring nucleic acid concentration offers potential in diagnosing cancer and further developing an understanding of the biochemistry of disease. The application of Fourier transform infrared (FTIR) spectroscopy has previously been hindered by the supposed non-Beer-Lambert absorption behavior of DNA in intact cells making elucidation of the DNA bands difficult. We use known composition DNA/hemoglobin standards to successfully estimate the DNA content in avian erythrocyte nuclei (44.2%) and intact erythrocytes (12.8%). Furthermore we demonstrate that the absorption of cellular DNA does follow the Beer-Lambert Law and highlights the role of conformation and hydration in FTIR spectroscopy of biological samples. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. 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.

  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. 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.

  13. Advances in near-infrared spectroscopy to study the brain of the preterm and term neonate

    DEFF Research Database (Denmark)

    Wolf, Martin; Greisen, Gorm

    2009-01-01

    This article reviews tissue oximetry and imaging to study the preterm and newborn infant brain by near-infrared spectroscopy. These two technologies are now advanced; nearly 100 reports on their use in newborn infants have been published, and commercial instruments are available. The precision...

  14. Solid state spectroscopy by using of far-infrared synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nanba, Takao [Kobe Univ. (Japan). Faculty of Science

    1996-07-01

    If the spectroscopic system corresponding to the wavelength region required for experiment is installed, the light source with continuous wavelength is to be obtainable by synchrotron radiation. This report is that of the research on solid state spectroscopy using the ordinary incoherent synchrotron radiation which is obtained from the deflection electromagnet parts of electron storage ring. At present in the world, the facilities which can be utilized in far-infrared spectroscopy region are five, including the UVSOR of Molecular Science Research Institute in Japan. The optical arrangement of the measuring system of the UVSOR is shown. The spectrum distribution of the light passing through the pinholes with different diameter in the place of setting samples was compared in case of the UVSOR and a high pressure mercury lamp, and it was shown that synchrotron radiation has high luminance. The researches on solid state spectroscopy carried out in the above mentioned five facilities are enumerated. In this paper, the high pressure spectroscopic experiment which has been carried out at the UVSOR is reported. The observation of the phase transition of fine particles and the surface phonons of fine particles are described. As fine particle size became smaller, the critical pressure at which phase transition occurred was high. (K.I.)

  15. [Near-infrared spectroscopy as an auxiliary tool in the study of child development].

    Science.gov (United States)

    Oliveira, Suelen Rosa de; Machado, Ana Carolina Cabral de Paula; Miranda, Débora Marques de; Campos, Flávio Dos Santos; Ribeiro, Cristina Oliveira; Magalhães, Lívia de Castro; Bouzada, Maria Cândida Ferrarez

    2015-01-01

    To investigate the applicability of Near-Infrared Spectroscopy (NIRS) for cortical hemodynamic assessment tool as an aid in the study of child development. Search was conducted in the PubMed and Lilacs databases using the following keywords: "psychomotor performance/child development/growth and development/neurodevelopment/spectroscopy/near-infrared" and their equivalents in Portuguese and Spanish. The review was performed according to criteria established by Cochrane and search was limited to 2003 to 2013. English, Portuguese and Spanish were included in the search. Of the 484 articles, 19 were selected: 17 cross-sectional and two longitudinal studies, published in non-Brazilian journals. The analyzed articles were grouped in functional and non-functional studies of child development. Functional studies addressed the object processing, social skills development, language and cognitive development. Non-functional studies discussed the relationship between cerebral oxygen saturation and neurological outcomes, and the comparison between the cortical hemodynamic response of preterm and term newborns. NIRS has become an increasingly feasible alternative and a potentially useful technique for studying functional activity of the infant brain. Copyright © 2015 Associação de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

  16. Challenges in the noninvasive detection of body composition using near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Wenliang Chen

    2014-11-01

    Full Text Available Noninvasive detection of body composition plays a significant role in the improvement of life quality and reduction in complications of the patients, and the near-infrared (NIR spectroscopy, with the advantages of painlessness and convenience, is considered as the most promising tool for the online noninvasive monitoring of body composition. However, quite different from other fields of online detection using NIR spectroscopy, such as food safety and environment monitoring, noninvasive detection of body composition demands higher precision of the instruments as well as more rigorousness of measurement conditions. Therefore, new challenges emerge when NIR spectroscopy is applied to the noninvasive detection of body composition, which, in this paper, are first concluded from the aspects of measurement methods, measurement conditions, instrument precision, multi-component influence, individual difference and novel weak-signal extraction method based on our previous research in the cutting-edge field of NIR noninvasive blood glucose detection. Moreover, novel ideas and approaches of our group to solve these problems are introduced, which may provide evidence for the future development of noninvasive blood glucose detection, and further contribute to the noninvasive detection of other body compositions using NIR spectroscopy.

  17. 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).

  18. 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.

  19. 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).

  20. Monitoring wine aging with Fourier transform infrared spectroscopy (FT-IR

    Directory of Open Access Journals (Sweden)

    Basalekou Marianthi

    2015-01-01

    Full Text Available Oak wood has commonly been used in wine aging but recently other wood types such as Acacia and Chestnut, have attracted the interest of the researchers due to their possible positive contribution to wine quality. However, only the use of oak and chestnut woods is approved by the International Enological Codex of the International Organisation of Vine and Wine. In this study Fourier Transform (FT-mid-infrared spectroscopy combined with Discriminant Analysis was used to differentiate wines aged in barrels made from French oak, American oak, Acacia and Chestnut and in tanks with oak chips, over a period of 12 months. Two red (Mandilaria, Kotsifali and two white (Vilana, Dafni native Greek grape varieties where used to produce four wines. The Fourier Transform Infrared (FT-IR spectra of the samples were recorded on a Zinc Selenide (ZnSe window after incubation at 40 °C for 30 min. A complete differentiation of the samples according to both the type of wood used and the contact time was achieved based on their FT-IR spectra.

  1. Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers

    Directory of Open Access Journals (Sweden)

    Ben Jones

    2018-04-01

    Full Text Available The development of an underwater near-infrared spectroscopy (uNIRS device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i to trial the use of uNIRS, in a real world training study, and (ii to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis. uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming.

  2. [Application of Fourier transform infrared spectroscopy in identification of wine spoilage].

    Science.gov (United States)

    Zhao, Xian-De; Dong, Da-Ming; Zheng, Wen-Gang; Jiao, Lei-Zi; Lang, Yun

    2014-10-01

    In the present work, fresh and spoiled wine samples from three wines produced by different companies were studied u- sing Fourier transform infrared (FTIR) spectroscopy. We analyzed the physicochemical property change in the process of spoil- age, and then, gave out the attribution of some main FTIR absorption peaks. A novel determination method was explored based on the comparisons of some absorbance ratios at different wavebands although the absorbance ratios in this method were relative. Through the compare of the wine spectra before and after spoiled, the authors found that they were informative at the bands of 3,020~2,790, 1,760~1,620 and 1,550~800 cm(-1). In order to find the relation between these informative spectral bands and the wine deterioration and achieve the discriminant analysis, chemometrics methods were introduced. Principal compounds analysis (PCA) and soft independent modeling of class analogy (SIMCA) were used for classifying different-quality wines. And partial least squares discriminant analysis (PLS-DA) was applied to identify spoiled wines and good wines. Results showed that FTIR technique combined with chemometrics methods could effectively distinguish spoiled wines from fresh samples. The effect of classification at the wave band of 1 550-800 cm(-1) was the best. The recognition rate of SIMCA and PLSDA were respectively 94% and 100%. This study demonstrates that Fourier transform infrared spectroscopy is an effective tool for monitoring red wine's spoilage and provides theoretical support for developing early-warning equipments.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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...

  8. A mesenteric traction syndrome affects near-infrared spectroscopy evaluated cerebral oxygenation because skin blood flow increases

    DEFF Research Database (Denmark)

    Olesen, Niels D; Sørensen, Henrik; Ambrus, Rikard

    2018-01-01

    During abdominal surgery manipulation of internal organs may induce a "mesenteric traction syndrome" (MTS) including a triad of flushing, hypotension, and tachycardia that lasts for about 30 min. We evaluated whether MTS affects near-infrared spectroscopy (NIRS) assessed frontal lobe oxygenation ...

  9. Increased prefrontal hemodynamic change after atomoxetine administration in pediatric attention-deficit/hyperactivity disorder as measured by near-infrared spectroscopy.

    Science.gov (United States)

    Ota, Toyosaku; Iida, Junzo; Nakanishi, Yoko; Sawada, Satomi; Matsuura, Hiroki; Yamamuro, Kazuhiko; Ueda, Shotaro; Uratani, Mitsuhiro; Kishimoto, Naoko; Negoro, Hideki; Kishimoto, Toshifumi

    2015-03-01

    Atomoxetine, approved in Japan for the treatment of pediatric attention-deficit/hyperactivity disorder (ADHD) in April 2009, is a nonstimulant that is thought to act presynaptically via the inhibition of norepinephrine reuptake. Near-infrared spectroscopy is a non-invasive optical tool that can be used to study oxygenation and hemodynamic changes in the cerebral cortex. The present study examined the effects of a clinical dose of atomoxetine on changes in prefrontal hemodynamic activity in children with ADHD, as measured by near-infrared spectroscopy using the Stroop Color-Word Task. Ten children with ADHD participated in the present study. We used 24-channel near-infrared spectroscopy to measure the relative concentrations of oxyhemoglobin in the frontal lobes of participants in the drug-naïve condition and those who had received atomoxetine for 8 weeks. Measurements were conducted every 0.1 s during the Stroop Color-Word Task. We used the ADHD Rating Scale-IV-Japanese version (Home Version) to evaluate ADHD symptoms. We found a significant decrease in ADHD Rating Scale-IV-Japanese version scores, from 30.7 to 22.6 (P=0.003). During the Stroop Color-Word Task, we found significantly higher levels of oxyhemoglobin changes in the prefrontal cortex of participants in the atomoxetine condition compared with those in the drug-naïve condition. This increase in oxyhemoglobin changes might indicate an intensified prefrontal hemodynamic response induced by atomoxetine. Near-infrared spectroscopy is a sensitive tool for measuring the pharmacological effects of atomoxetine in children with ADHD. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  10. Moessbauer spectroscopy, X-ray diffraction and infrared studies of prehistoric materials from Minas Gerais

    International Nuclear Information System (INIS)

    Jesus Filho, M.F. de; Costa, G.M. da; Prous, A.

    1988-01-01

    Eight samples of pigmented materials from an archaelogical site in Santana do Riacho (Minas Gerais, Brazil) were studied by X-ray diffraction, infrared and Moessbauer spectroscopy. These three techniques and the results of chemical analysis allowed the approximated composition of each sample to be proposed. No trace of organic material was found in any sample. (author)

  11. Analytical applications of spectroscopy

    International Nuclear Information System (INIS)

    Creaser, C.S.

    1988-01-01

    This book provides an up to date overview of recent developments in analytical spectroscopy, with a particular emphasis on the common themes of chromatography - spectroscopy combinations, Fourier transform methods, and data handling techniques, which have played an increasingly important part in the development of all spectroscopic techniques. The book contains papers originally presented at a conference entitled 'Spectroscopy Across The Spectrum' held jointly with the first 'International Near Infrared Spectroscopy Conference' at the University of East Anglia, Norwich, UK, in July 1987, which have been edited and rearranged with some additional material. Each section includes reviews of key areas of current research as well as short reports of new developments. The fields covered are: Near Infrared Spectroscopy; Infrared Spectroscopy; Mass Spectroscopy; NMR Spectroscopy; Atomic and UV/Visible Spectroscopy; Chemometrics and Data Analysis. (author)

  12. Headspace analysis gas-phase infrared spectroscopy: a study of xanthate decomposition on mineral surfaces

    Science.gov (United States)

    Vreugdenhil, Andrew J.; Brienne, Stephane H. R.; Markwell, Ross D.; Butler, Ian S.; Finch, James A.

    1997-03-01

    The O-ethyldithiocarbonate (ethyl xanthate, CH 3CH 2OCS -2) anion is a widely used reagent in mineral processing for the separation of sulphide minerals by froth flotation. Ethyl xanthate interacts with mineral powders to produce a hydrophobic layer on the mineral surface. A novel infrared technique, headspace analysis gas-phase infrared spectroscopy (HAGIS) has been used to study the in situ thermal decomposition products of ethyl xanthate on mineral surfaces. These products include CS 2, COS, CO 2, CH 4, SO 2, and higher molecular weight alkyl-containing species. Decomposition pathways have been proposed with some information determined from 2H- and 13C-isotope labelling experiments.

  13. Charge Order in (TMTTF)2TaF6 by Infrared Spectroscopy

    Science.gov (United States)

    Oka, Yuki; Matsunaga, Noriaki; Nomura, Kazushige; Kawamoto, Atsuhi; Yamamoto, Kaoru; Yakushi, Kyuya

    2015-11-01

    We have performed infrared spectroscopy in (TMTTF)2TaF6 (TMTTF: tetramethyltetrathiafulvalene) to investigate the relationship between the charge order (CO) state and the antiferromagnetic (AF) insulating ground state. A clear peak splitting corresponding to the charge disproportionation was observed below the CO transition temperature. We estimated the degree of charge disproportionation, Δρ = ρrich - ρpoor, as 0.28e from the peak splitting and found that the CO state coexists with the AF state and there is no charge redistribution below the AF transition.

  14. A review of near infrared spectroscopy and chemometrics in pharmaceutical technologies.

    Science.gov (United States)

    Roggo, Yves; Chalus, Pascal; Maurer, Lene; Lema-Martinez, Carmen; Edmond, Aurélie; Jent, Nadine

    2007-07-27

    Near-infrared spectroscopy (NIRS) is a fast and non-destructive analytical method. Associated with chemometrics, it becomes a powerful tool for the pharmaceutical industry. Indeed, NIRS is suitable for analysis of solid, liquid and biotechnological pharmaceutical forms. Moreover, NIRS can be implemented during pharmaceutical development, in production for process monitoring or in quality control laboratories. This review focuses on chemometric techniques and pharmaceutical NIRS applications. The following topics are covered: qualitative analyses, quantitative methods and on-line applications. Theoretical and practical aspects are described with pharmaceutical examples of NIRS applications.

  15. Biodiesel classification by base stock type (vegetable oil) using near infrared spectroscopy data

    Energy Technology Data Exchange (ETDEWEB)

    Balabin, Roman M., E-mail: balabin@org.chem.ethz.ch [Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich (Switzerland); Safieva, Ravilya Z. [Gubkin Russian State University of Oil and Gas, 119991 Moscow (Russian Federation)

    2011-03-18

    The use of biofuels, such as bioethanol or biodiesel, has rapidly increased in the last few years. Near infrared (near-IR, NIR, or NIRS) spectroscopy (>4000 cm{sup -1}) has previously been reported as a cheap and fast alternative for biodiesel quality control when compared with infrared, Raman, or nuclear magnetic resonance (NMR) methods; in addition, NIR can easily be done in real time (on-line). In this proof-of-principle paper, we attempt to find a correlation between the near infrared spectrum of a biodiesel sample and its base stock. This correlation is used to classify fuel samples into 10 groups according to their origin (vegetable oil): sunflower, coconut, palm, soy/soya, cottonseed, castor, Jatropha, etc. Principal component analysis (PCA) is used for outlier detection and dimensionality reduction of the NIR spectral data. Four different multivariate data analysis techniques are used to solve the classification problem, including regularized discriminant analysis (RDA), partial least squares method/projection on latent structures (PLS-DA), K-nearest neighbors (KNN) technique, and support vector machines (SVMs). Classifying biodiesel by feedstock (base stock) type can be successfully solved with modern machine learning techniques and NIR spectroscopy data. KNN and SVM methods were found to be highly effective for biodiesel classification by feedstock oil type. A classification error (E) of less than 5% can be reached using an SVM-based approach. If computational time is an important consideration, the KNN technique (E = 6.2%) can be recommended for practical (industrial) implementation. Comparison with gasoline and motor oil data shows the relative simplicity of this methodology for biodiesel classification.

  16. Biodiesel classification by base stock type (vegetable oil) using near infrared spectroscopy data

    International Nuclear Information System (INIS)

    Balabin, Roman M.; Safieva, Ravilya Z.

    2011-01-01

    The use of biofuels, such as bioethanol or biodiesel, has rapidly increased in the last few years. Near infrared (near-IR, NIR, or NIRS) spectroscopy (>4000 cm -1 ) has previously been reported as a cheap and fast alternative for biodiesel quality control when compared with infrared, Raman, or nuclear magnetic resonance (NMR) methods; in addition, NIR can easily be done in real time (on-line). In this proof-of-principle paper, we attempt to find a correlation between the near infrared spectrum of a biodiesel sample and its base stock. This correlation is used to classify fuel samples into 10 groups according to their origin (vegetable oil): sunflower, coconut, palm, soy/soya, cottonseed, castor, Jatropha, etc. Principal component analysis (PCA) is used for outlier detection and dimensionality reduction of the NIR spectral data. Four different multivariate data analysis techniques are used to solve the classification problem, including regularized discriminant analysis (RDA), partial least squares method/projection on latent structures (PLS-DA), K-nearest neighbors (KNN) technique, and support vector machines (SVMs). Classifying biodiesel by feedstock (base stock) type can be successfully solved with modern machine learning techniques and NIR spectroscopy data. KNN and SVM methods were found to be highly effective for biodiesel classification by feedstock oil type. A classification error (E) of less than 5% can be reached using an SVM-based approach. If computational time is an important consideration, the KNN technique (E = 6.2%) can be recommended for practical (industrial) implementation. Comparison with gasoline and motor oil data shows the relative simplicity of this methodology for biodiesel classification.

  17. Validation of mid-infrared spectroscopy for macronutrient analysis of human milk.

    Science.gov (United States)

    Parat, S; Groh-Wargo, S; Merlino, S; Wijers, C; Super, D M

    2017-07-01

    Human milk has considerable variation in its composition. Hence, the nutrient profile is only an estimate and can result in under- or over-estimation of the intake of preterm infants. Mid-infrared (MIR) spectroscopy is an evolving technique for analyzing human milk but needs validation before use in clinical practice. Human milk samples from 35 mothers delivering at 35 weeks to term gestation were analyzed for macronutrients by MIR spectroscopy and by standard laboratory methods using Kjeldahl assay for protein, Mojonnier assay for fat and high-pressure liquid chromatography assay for lactose. MIR analysis of the macronutrients in human milk correlated well with standard laboratory tests with intraclass correlation coefficients of 0.997 for fat, 0.839 for protein and 0.776 for lactose. Agreement between the two methods was excellent for fat, and moderate for protein and lactose (Pmilk. Agreement between the methodologies varies by macronutrient.

  18. A prototype stationary Fourier transform spectrometer for near-infrared absorption spectroscopy.

    Science.gov (United States)

    Li, Jinyang; Lu, Dan-feng; Qi, Zhi-mei

    2015-09-01

    A prototype stationary Fourier transform spectrometer (FTS) was constructed with a fiber-coupled lithium niobate (LiNbO3) waveguide Mach-Zehnder interferometer (MZI) for the purpose of rapid on-site spectroscopy of biological and chemical measurands. The MZI contains push-pull electrodes for electro-optic modulation, and its interferogram as a plot of intensity against voltage was obtained by scanning the modulating voltage from -60 to +60 V in 50 ms. The power spectrum of input signal was retrieved by Fourier transform processing of the interferogram combined with the wavelength dispersion of half-wave voltage determined for the MZI used. The prototype FTS operates in the single-mode wavelength range from 1200 to 1700 nm and allows for reproducible spectroscopy. A linear concentration dependence of the absorbance at λmax = 1451 nm for water in ethanolic solution was obtained using the prototype FTS. The near-infrared spectroscopy of solid samples was also implemented, and the different spectra obtained with different materials evidenced the chemical recognition capability of the prototype FTS. To make this prototype FTS practically applicable, work on improving its spectral resolution by increasing the maximum optical path length difference is in progress.

  19. 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).

  20. 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.

  1. IRMPD Spectroscopy Sheds New (Infrared) Light on the Sulfate Pattern of Carbohydrates.

    Science.gov (United States)

    Schindler, B; Barnes, L; Gray, C J; Chambert, S; Flitsch, S L; Oomens, J; Daniel, R; Allouche, A R; Compagnon, I

    2017-03-16

    IR spectroscopy of gas-phase ions is proposed to resolve positional isomers of sulfated carbohydrates. Mass spectrometric fingerprints and gas-phase vibrational spectra in the near and mid-IR regions were obtained for sulfated monosaccharides, yielding unambiguous signatures of sulfated isomers. We report the first systematic exploration of the biologically relevant but notoriously challenging deprotonated state in the near IR region. Remarkably, anions displayed very atypical vibrational profiles, which challenge the well-established DFT (Density Functionnal Theory) modeling. The proposed approach was used to elucidate the sulfate patterns in glycosaminoglycans, a ubiquitous class of mammalian carbohydrates, which is regarded as a major challenge in carbohydrate structural analysis. Isomeric glycosaminoglycan disaccharides from heparin and chondroitin sources were resolved, highlighting the potential of infrared multiple photon dissociation spectroscopy as a novel structural tool for carbohydrates.

  2. Mössbauer and infrared spectroscopy as a diagnostic tool for the characterization of ferric tannates

    Science.gov (United States)

    Jaén, Juan A.; Navarro, César

    2009-07-01

    Fourier transform infrared spectroscopy and Mössbauer spectroscopy are use for the characterization and qualitative analysis of hydrolysable and condensed tannates. The two classes of tannates may be differentiated from the characteristic IR pattern. Mössbauer proof that a mixture of mono- and bis-type ferric tannate complexes, and an iron(II)-tannin complex are obtained from the interaction of hydrolysable tannins (tannic acid and chestnut tannin) and condensed tannins (mimosa and quebracho) with a ferric nitrate solution. At pH 7, a partially hydrolyzed ferric tannate complex was also obtained.

  3. Investigation into interaction of CO/sub 2/ molecules with zeolites by infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ignat' eva, L A; Levshin, L V; Chukin, G D; Efimenko, L V; Kozlova, T I [Moskovskij Gosudarstvennyj Univ. (USSR). Kafedra Optiki

    1975-07-01

    Interaction of CO/sub 2/ molecules with zeolites, particularly with SrNaJ was studied by infrared-spectroscopy. To obtain infrared-spectra the zeolites were pressed into tablets and were calcinated at 500 deg. In the spectra the bands of chemisorbed CO/sub 2/ absorption were found in the range 1300 - 1600 cm/sup -1/. The CO/sub 2/ molecule was found to be strongly deformed due to chemisorption. In terms of electronic structure of the zeolite crystalline skeleton several types of CO/sub 2/ molecules interaction with different active zeolites were found. The position of the high-frequency band of CO/sub 2/ absorption in zeolites spectra was found to be a linear function of electrostatic field of the cations.

  4. 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.

  5. 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.

  6. André Blumel, un itinéraire sioniste à la croisée des chemins

    OpenAIRE

    Lafon, François

    2009-01-01

    Cet article envisage à travers l’itinéraire sioniste d’André Blumel les relations entre la gauche française et l’État d’Israël. Proche de Léon Blum, dont il fut directeur de Cabinet durant le Front populaire, mais se rapprochant progressivement des communistes, Blumel demeura jusqu’en 1966 une figure clefs des milieux sionistes français. Conciliant divers engagements – pourtant apparemment contradictoires – son parcours permet de comprendre la complexité des liens et des conflits qui caractér...

  7. GROUPING OF ORAL STREPTOCOCCAL SPECIES USING FOURIER-TRANSFORM INFRARED-SPECTROSCOPY IN COMPARISON WITH CLASSICAL MICROBIOLOGICAL IDENTIFICATION

    NARCIS (Netherlands)

    VANDERMEI, HC; NAUMANN, D; BUSSCHER, HJ

    1993-01-01

    The grouping and identification made by Fourier-transform infrared spectroscopy (FT-IR) of 40 oral streptococcal strains was compared with their known taxonomic positions. Grouping was obtained by cluster analysis on the spectral distances between the first derivative spectra of the strains. Spectra

  8. Multivariate Calibration and Model Integrity for Wood Chemistry Using Fourier Transform Infrared Spectroscopy

    OpenAIRE

    Zhou, Chengfeng; Jiang, Wei; Cheng, Qingzheng; Via, Brian K.

    2015-01-01

    This research addressed a rapid method to monitor hardwood chemical composition by applying Fourier transform infrared (FT-IR) spectroscopy, with particular interest in model performance for interpretation and prediction. Partial least squares (PLS) and principal components regression (PCR) were chosen as the primary models for comparison. Standard laboratory chemistry methods were employed on a mixed genus/species hardwood sample set to collect the original data. PLS was found to provide bet...

  9. Near-infrared-excited confocal Raman spectroscopy advances in vivo diagnosis of cervical precancer.

    Science.gov (United States)

    Duraipandian, Shiyamala; Zheng, Wei; Ng, Joseph; Low, Jeffrey J H; Ilancheran, Arunachalam; Huang, Zhiwei

    2013-06-01

    Raman spectroscopy is a unique optical technique that can probe the changes of vibrational modes of biomolecules associated with tissue premalignant transformation. This study evaluates the clinical utility of confocal Raman spectroscopy over near-infrared (NIR) autofluorescence (AF) spectroscopy and composite NIR AF/Raman spectroscopy for improving early diagnosis of cervical precancer in vivo at colposcopy. A rapid NIR Raman system coupled with a ball-lens fiber-optic confocal Raman probe was utilized for in vivo NIR AF/Raman spectral measurements of the cervix. A total of 1240 in vivo Raman spectra [normal (n=993), dysplasia (n=247)] were acquired from 84 cervical patients. Principal components analysis (PCA) and linear discriminant analysis (LDA) together with a leave-one-patient-out, cross-validation method were used to extract the diagnostic information associated with distinctive spectroscopic modalities. The diagnostic ability of confocal Raman spectroscopy was evaluated using the PCA-LDA model developed from the significant principal components (PCs) [i.e., PC4, 0.0023%; PC5, 0.00095%; PC8, 0.00022%, (p<0.05)], representing the primary tissue Raman features (e.g., 854, 937, 1095, 1253, 1311, 1445, and 1654 cm(-1)). Confocal Raman spectroscopy coupled with PCA-LDA modeling yielded the diagnostic accuracy of 84.1% (a sensitivity of 81.0% and a specificity of 87.1%) for in vivo discrimination of dysplastic cervix. The receiver operating characteristic curves further confirmed that the best classification was achieved using confocal Raman spectroscopy compared to the composite NIR AF/Raman spectroscopy or NIR AF spectroscopy alone. This study illustrates that confocal Raman spectroscopy has great potential to improve early diagnosis of cervical precancer in vivo during clinical colposcopy.

  10. 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.

  11. Terahertz time-domain spectroscopy response of amines and amino acids intercalated smectites in far-infrared region

    Energy Technology Data Exchange (ETDEWEB)

    Janek, M., E-mail: marian.janek@fns.uniba.sk [Comenius University, Faculty of Natural Sciences, Department of Physical and Theoretical Chemistry, Mlynská dolina CH1, SK-84215 Bratislava (Slovakia); Zich, D. [Comenius University, Faculty of Natural Sciences, Department of Physical and Theoretical Chemistry, Mlynská dolina CH1, SK-84215 Bratislava (Slovakia); Naftaly, M., E-mail: mira.naftaly@npl.co.uk [National Physical Laboratory, Hampton Rd, Teddington, Middlesex TW11 0LW (United Kingdom)

    2014-06-01

    Layered clay minerals from the smectite group with different chemical composition and resulting layer charge (e.g. pyrophyllite, illite, hectorite and montmorillonite) were characterised for their dielectric properties in the far-infrared region using terahertz-time domain spectroscopy (THz-TDS). Samples with distinct cation exchange capacity such as hectorite and montmorillonite were modified using cation exchange reaction with alkylamines or amino acids. The presence of these species in 2D gallery was proved by X-ray diffraction and Fourier transform infrared spectroscopy. The frequency-dependent refractive index of these minerals was determined in the experimentally accessible range of 0.1–3.0 THz (3–100 cm{sup −1}) using THz-TDS. Pristine samples revealed their refractive indices to be 1.82–2.15 at about 1 THz while the modified montmorillonite samples had their refractive indices changed by organic molecules used for their modification to 1.70–2.35 for amines and 1.97–2.36 for amino acids. The presence of organic substances in 2D gallery of clays was detectable despite the relatively high absorption of smectites with magnitude of 100 cm{sup −1}. - Graphical abstract: Display Omitted - Highlights: • “Guest” molecules in “host” layered material were investigated. • Amines and amino-acids were selected as guest molecules. • Natural and synthetic host with smectite phyllosilicate structure were used. • Dielectric properties were investigated by terahertz time domain spectroscopy. • Resonance absorption peaks of guest were detected in far infrared region.

  12. 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

  13. 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.

  14. Twenty years of functional near-infrared spectroscopy: introduction for the special issue.

    Science.gov (United States)

    Boas, David A; Elwell, Clare E; Ferrari, Marco; Taga, Gentaro

    2014-01-15

    Papers from four different groups were published in 1993 demonstrating the ability of functional near infrared spectroscopy (fNIRS) to non-invasively measure hemoglobin concentration responses to brain function in humans. This special issue commemorates the first 20years of fNIRS research. The 9 reviews and 49 contributed papers provide a comprehensive survey of the exciting advances driving the field forward and of the myriad of applications that will benefit from fNIRS. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Optical nanoantennas for multiband surface-enhanced infrared and raman spectroscopy

    KAUST Repository

    D'Andrea, Cristiano; Bochterle, Jö rg; Toma, Andrea; Huck, Christian W.; Neubrech, Frank; Messina, Elena; Fazio, Barbara; Maragó , Onofrio M.; Di Fabrizio, Enzo M.; Lamy De La Chapelle, Marc L.; Gucciardi, Pietro Giuseppe; Pucci, Annemarie

    2013-01-01

    In this article we show that linear nanoantennas can be used as shared substrates for surface-enhanced Raman and infrared spectroscopy (SERS and SEIRS, respectively). This is done by engineering the plasmonic properties of the nanoantennas, so to make them resonant in both the visible (transversal resonance) and the infrared (longitudinal resonance), and by rotating the excitation field polarization to selectively take advantage of each resonance and achieve SERS and SEIRS on the same nanoantennas. As a proof of concept, we have fabricated gold nanoantennas by electron beam lithography on calcium difluoride (1-2 μm long, 60 nm wide, 60 nm high) that exhibit a transverse plasmonic resonance in the visible (640 nm) and a particularly strong longitudinal dipolar resonance in the infrared (tunable in the 1280-3100 cm -1 energy range as a function of the length). SERS and SEIRS detection of methylene blue molecules adsorbed on the nanoantenna's surface is accomplished, with signal enhancement factors of 5 × 102 for SERS (electromagnetic enhancement) and up to 105 for SEIRS. Notably, we find that the field enhancement provided by the transverse resonance is sufficient to achieve SERS from single nanoantennas. Furthermore, we show that by properly tuning the nanoantenna length the signals of a multitude of vibrational modes can be enhanced with SEIRS. This simple concept of plasmonic nanosensor is highly suitable for integration on lab-on-a-chip schemes for label-free chemical and biomolecular identification with optimized performances. © 2013 American Chemical Society.

  16. Identification and characterization of salmonella serotypes using DNA spectral characteristics by fourier transform infrared (FT-IR) spectroscopy

    Science.gov (United States)

    Analysis of DNA samples of Salmonella serotypes (Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky) were performed using Fourier transform infrared spectroscopy (FT-IR) spectrometer by placing directly in contact with a diamond attenua...

  17. Ultra-Broadband Infrared Pulses from a Potassium-Titanyl Phosphate Optical Parametric Amplifier for VIS-IR-SFG Spectroscopy

    Science.gov (United States)

    Isaienko, Oleksandr; Borguet, Eric

    A non-collinear KTP-OPA to provide ultra-broadband mid-infrared pulses was designed and characterized. With proper pulse-front and phase correction, the system has a potential for high-time resolution vibrational VIS-IR-SFG spectroscopy.

  18. Rapid determination of acetic acid, furfural and 5-hydroxymethylfurfural in biomass hydrolysate using near-infrared spectroscopy

    Science.gov (United States)

    Near infrared spectroscopy (NIR) is a rapid detection technique that has been used to characterize biomass. The objective of this study was to develop suitable NIR models to predict the acetic acid, furfural, and 5-hydroxymethylfurfural (HMF) contents in biomass hydrolysates. Using a uniform distrib...

  19. 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...

  20. Use of near infrared spectroscopy to measure the chemical and mechanical properties of solid wood

    Science.gov (United States)

    Stephen S. Kelley; Timothy G. Rials; Rebecca Snell; Leslie H. Groom; Amie Sluiter

    2004-01-01

    Near infrared (NIR) spectroscopy (500 nm-2400 nm), coupled with multivariate analytic (MVA) statistical techniques, have been used to predict the chemical and mechanical properties of solid loblolly pine wood. The samples were selected from different radial locations and heights of three loblolly pine trees grown in Arkansas. The chemical composition and mechanical...

  1. 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...

  2. 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.

  3. Detection and classification of salmonella serotypes using spectral signatures collected by fourier transform infrared (FT-IR) spectroscopy

    Science.gov (United States)

    Spectral signatures of Salmonella serotypes namely Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Heidelberg and Salmonella Kentucky were collected using Fourier transform infrared spectroscopy (FT-IR). About 5-10 µL of Salmonella suspensions with concentrations of 1...

  4. [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.

  5. Nanocomposites of polypropylene and organophilic clay: X ray diffraction, absorption infrared spectroscopy with fourier transform and water vapor permeation

    International Nuclear Information System (INIS)

    Morelli, Fernanda C.; Ruvolo Filho, Adhemar

    2010-01-01

    In this work nano composites were prepared from polypropylene, graft polypropylene with maleic anhydride as compatibilizer and organophilic montmorillonite Cloisite 20A with concentrations of 1.5, 2.5, 5.0 and 7.5% clay. The mixture was made in the melt state using a twin screw extruder. The materials were characterized by X ray diffraction, infrared spectroscopy with Fourier transform and analysis of water vapor permeation. The results of X ray diffraction and absorption infrared spectroscopy indicates the formation of nano composites with structures probably exfoliate and or intercalated for concentrations of 1.5 and 2.5% clay, and provided a marked decrease in the water permeability, corroborating with other analyses. (author)

  6. Mid-infrared spectroscopy and multivariate analysis for determination of tetracycline residues in cow's milk

    Directory of Open Access Journals (Sweden)

    Lizeth Mariel Casarrubias-Torres

    2018-01-01

    Full Text Available Mid-infrared spectroscopy and chemometric analysis were tested to determine tetracycline's residues in cow's milk. Cow's milk samples (n = 30 were spiked with tetracycline, chlortetracycline, and oxytetracycline in the range of 10-400 µg/l. Chemometric models to quantify each of the tetracycline's residues were developed by applying Partial Components Regression and Partial Least Squares algorithms. The Soft Independent Modeling of Class Analogy model was used to differentiate between pure milk and milk sample with tetracycline residues. The best models for predicting the levels of these antibiotics were obtained using Partial Least Square 1 algorithm (coefficient of determination between 0.997-0.999 and the standard error of calibration from 1.81 to 2.95. The Soft Independent Modeling of Class Analogy model showed well-separated groups allowing classification of milk samples and milk sample with antibiotics. The obtained results demonstrate the great analytical potential of chemometrics coupled with mid-infrared spectroscopy for the prediction of antibiotic in cow's milk at a concentration of microgram per litre (µg/l. This technique can be used to verify the safety of the milk rapidly and reliably.

  7. Fast determination of the resin and rubber content in Parthenium argentatum biomass using near infrared spectroscopy

    NARCIS (Netherlands)

    Suchat, S.; Pioch, D.; Palu, S.; Tardan, E.; Loo, van E.N.; Davrieux, F.

    2013-01-01

    Guayule (Parthenium argentatum), a plant native of semi-arid regions of northern Mexico and southern Texas, United States, is an under-used source of hypoallergenic latex, a solution to the serious latex allergy IgE problem worldwide. This study aimed to develop near infrared spectroscopy (NIRS)

  8. 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

  9. Nondestructive determination of nutritional information in oilseed rape leaves using visible/near infrared spectroscopy and multivariate calibrations

    NARCIS (Netherlands)

    Liu Fei, [No Value; Nie PengCheng, [No Value; Huang Min, [No Value; Kong WenWen, [No Value; He Yong, [No Value

    Nitrogen, phosphorus and potassium content are the three most important nutritional parameters for growing oilseed rape. We investigated visible and near infrared (Vis/NIR) spectroscopy combined with chemometrics for the fast and nondestructive determination of nutritional information in oilseed

  10. Insights on diagnosis of oral cavity pathologies by infrared spectroscopy: A review

    Science.gov (United States)

    Giorgini, Elisabetta; Balercia, Paolo; Conti, Carla; Ferraris, Paolo; Sabbatini, Simona; Rubini, Corrado; Tosi, Giorgio

    2013-11-01

    Fourier-Transform Infrared microspectroscopy, a largely used spectroscopic technique in basic and industrial researches, offers the possibility to analyze the vibrational features of molecular groups within a variety of environments. In the bioclinical field, and, in particular, in the study of cells, tissues and biofluids, it could be considered a supporting objective technique able to characterize the biochemical processes involved in relevant pathologies, such as tumoral diseases, highlighting specific spectral markers associable with the principal biocomponents (proteins, lipids and carbohydrates). In this article, we review the applications of infrared spectroscopy to the study of tumoral diseases of oral cavity compartments with the aim to improve understanding of biological processes involved during the onset of these lesions and to afford to an early diagnosis. Spectral studies on mouth, salivary glands and oral cystic lesions, objectively discriminate normal from dysplastic and cancer states characterizing also the grading.

  11. Determining the clay/organic carbon ratio by visible near infrared spectroscopy

    DEFF Research Database (Denmark)

    Knadel, Maria; Peng, Yi; Hermansen, Cecilie

    /OC ratio directly would be valuable. Visible near infrared spectroscopy (vis-NIRS) is a cost-effective method for soil analysis and was tested here for the prediction of clay/OC ratio. Soil samples from two agricultural fields in Denmark (N=115) were analyzed. Partial Least Squares regression (full cross......The recently presented Dexter et al. (2008) threshold (ratio of clay to organic carbon (OC) of 10 kg/kg-1) is a good indicator for soil functional properties. However, the conventional analysis of OC and clay are costly and time consuming, thus an alternative method to quantify OC, clay or clay...

  12. 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.

  13. 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.

  14. Reduced dorsolateral prefrontal cortical hemodynamic response in adult obsessive-compulsive disorder as measured by near-infrared spectroscopy during the verbal fluency task

    Directory of Open Access Journals (Sweden)

    Hirosawa R

    2013-07-01

    Full Text Available Rikuei Hirosawa,1 Jin Narumoto,1 Yuki Sakai,1 Seiji Nishida,2 Takuya Ishida,1 Takashi Nakamae,1 Yuichi Takei,3 Kenji Fukui1 1Department of Psychiatry, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, 2Maizuru Medical Center, Kyoto, 3Department of Psychiatry and Neuroscience, Gunma University Graduate School of Medicine, Gunma, Japan Background: Near-infrared spectroscopy has helped our understanding of the neurobiological mechanisms of psychiatric disorders and has advantages including noninvasiveness, lower cost, and ease of use compared with other imaging techniques, like functional magnetic resonance imaging. The verbal fluency task is the most common and well established task used to assess cognitive activation during near-infrared spectroscopy. Recent functional neuroimaging studies have shown that the orbitofrontal cortex and other brain regions, including the dorsolateral prefrontal cortex, may play important roles in the pathophysiology of obsessive-compulsive disorder (OCD. This study aimed to evaluate hemodynamic responses in the dorsolateral prefrontal cortex in patients with OCD using near-infrared spectroscopy during the verbal fluency task and to compare these with dorsolateral prefrontal cortex responses in healthy controls. Methods: Twenty patients with OCD and 20 controls matched for age, gender, handedness, and estimated intelligence quotient participated in this study. The verbal fluency task was used to elicit near-infrared spectroscopic activation and consisted of a 30-second pre-task, followed by three repetitions of a 20-second verbal fluency task (total 60 seconds, followed by a 70-second post-task period. The near-infrared spectroscopy experiment was conducted on the same day as surveys of obsessive-compulsive symptoms, depression, and anxiety. Z-scores for changes in the concentration of oxygenated hemoglobin were compared between the OCD patients and controls in 14 channels set over the

  15. 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.

  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. 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.

  18. 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.

  19. Spectroscopy

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    This introductory booklet covers the basics of molecular spectroscopy, infrared and Raman methods, instrumental considerations, symmetry analysis of molecules, group theory and selection rules, as well as assignments of fundamental vibrational modes in molecules.......This introductory booklet covers the basics of molecular spectroscopy, infrared and Raman methods, instrumental considerations, symmetry analysis of molecules, group theory and selection rules, as well as assignments of fundamental vibrational modes in molecules....

  20. Assessing Risk of Fumonisin Contamination in Maize Using Near-Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Cecile Levasseur-Garcia

    2015-01-01

    Full Text Available Fumonisins are major mycotoxins found worldwide in maize and maize products. Because of their toxicity for both human and animals, European Union regulations were created to fix the maximal fumonisin B1 and B2 content allowed in foods and feeds. Unfortunately, directly measuring these mycotoxins by current analytical techniques is tedious and expensive and most measurement methods do not lend themselves to online control. Alternative approaches to chemical analysis have been developed and involve models that allow the mycotoxin contamination to be predicted based on environmental conditions and analysis by near-infrared (NIR spectroscopy. In the present work, we use NIR spectroscopy to determine the fumonisin and fungal contents of 117 samples of maize. The determination coefficient between fumonisin and fungal-biomass content was 0.44. We establish herein a threshold for the number of CFUs for fungal biomass beyond which the fumonisin content is likely to exceed the European regulatory level of 4000 μg/kg. In addition, we determine the fungal content by using a NIR-spectroscopy model that allows us to sort samples of maize. Upon calibration, the percentage of well-classified samples was 96%, which compares favorably to the 82% obtained by independent verification.

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

    Directory of Open Access Journals (Sweden)

    Ming Dong

    2017-11-01

    Full Text Available 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.

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

    Science.gov (United States)

    Dong, Ming; Ren, Ming; Ye, Rixin

    2017-01-01

    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. PMID:29140268

  3. Hasard et nécessité dans la traduction littéraire

    Directory of Open Access Journals (Sweden)

    Irina ALDEA

    2010-11-01

    Full Text Available La relation nécessité-hasard spécifique pour l’acte de création de l’auteur se manifeste avec la même intensité dans l’acte de création du traducteur. L’acte de la traduction littéraire a des règles qui l’individualisent mais qui le maintiennent dans le cadre plus ample des éléments spécifiques à l’acte de création en général. On peut ainsi démontrer, à partir des concepts qui définissent la poïétique que l’acte de traduction est un véritable acte de création, que le traducteur est un auteur sui generis de l’œuvre.

  4. Quantifying ternary mixtures of different solid-state forms of indomethacin by Raman and near-infrared spectroscopy

    DEFF Research Database (Denmark)

    Heinz, Andrea; Savolainen, Marja; Rades, Thomas

    2007-01-01

    by mean centering proved to be the best approaches to pre-process the data. With four partial least squares factors, root mean square errors of prediction ranging from 5.3% to 6.5% for Raman spectroscopy and 4.0% to 5.9% for near-infrared spectroscopy were calculated. In addition, the effects of potential...... indomethacin. Partial least squares regression was employed to create quantitative models. To improve the model performance various pre-treatment algorithms and scaling methods were applied to the spectral data and different spectral regions were tested. Standard normal variate transformation and scaling...

  5. Fabrication of calix[4]pyrrole nanofilms at the glassy carbon surface and their characterization by spectroscopic, optic and electrochemical methods

    Energy Technology Data Exchange (ETDEWEB)

    Taner, Bilge; Ozcan, Emine [Selcuk University, Faculty of Science, Dept. of Chemistry, Konya (Turkey); Ustuendag, Zafer [Dumlupinar University, Faculty of Arts and Sciences, Dept. of Chemistry, Kuetahya (Turkey); Keskin, Selda [Middle East Technical University, Central Research Laboratory, Ankara (Turkey); Solak, Ali Osman, E-mail: osolak@science.ankara.edu.t [Ankara University, Faculty of Science, Department of Chemistry, Ankara (Turkey); Eksi, Haslet [Ankara University, Faculty of Science, Department of Chemistry, Ankara (Turkey)

    2010-10-29

    meso-Octamethylcalix[4]pyrrole (CP) and meso-heptaethylcalix[4]pyrrole-meso-4-aminophenyl (4APCP) modified glassy carbon (GC) electrodes were prepared by the electrochemical oxidation in acetonitrile solution. Binding of the calix[4]pyrroles with the glassy carbon surface was investigated that it is through the etheric linkage revealed from the reflection-absorption infrared spectroscopy (RAIRS). Surface films of CP and 4APCP were investigated by cyclic voltammetry (CV), ellipsometry, X-ray photoelectron spectroscopy, RAIRS and the contact angle measurements. The thicknesses of the films were determined by ellipsometry which confirmed that the film was multilayer and homogeneous over the surface. Ellipsometric measurements also provided that the CP and 4APCP film thicknesses were 2.49 nm and 4.58 nm for 6 CV cycle modification, corresponding to 66 {mu}F/cm{sup 2} and 106 {mu}F/cm{sup 2} capacitances obtained by CV. The wetting behavior was examined by contact angle measurements and found that the hydrophobicity of the GC-4APCP surface was higher than that of GC-CP, probably due to the aromatic meso substituent present in the former.

  6. Evaluation of light detector surface area for functional Near Infrared Spectroscopy.

    Science.gov (United States)

    Wang, Lei; Ayaz, Hasan; Izzetoglu, Meltem; Onaral, Banu

    2017-10-01

    Functional Near Infrared Spectroscopy (fNIRS) is an emerging neuroimaging technique that utilizes near infrared light to detect cortical concentration changes of oxy-hemoglobin and deoxy-hemoglobin non-invasively. Using light sources and detectors over the scalp, multi-wavelength light intensities are recorded as time series and converted to concentration changes of hemoglobin via modified Beer-Lambert law. Here, we describe a potential source for systematic error in the calculation of hemoglobin changes and light intensity measurements. Previous system characterization and analysis studies looked into various fNIRS parameters such as type of light source, number and selection of wavelengths, distance between light source and detector. In this study, we have analyzed the contribution of light detector surface area to the overall outcome. Results from Monte Carlo based digital phantoms indicated that selection of detector area is a critical system parameter in minimizing the error in concentration calculations. The findings here can guide the design of future fNIRS sensors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. 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.

  8. 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.

  9. Optical nanoantennas for multiband surface-enhanced infrared and raman spectroscopy

    KAUST Repository

    D'Andrea, Cristiano

    2013-04-23

    In this article we show that linear nanoantennas can be used as shared substrates for surface-enhanced Raman and infrared spectroscopy (SERS and SEIRS, respectively). This is done by engineering the plasmonic properties of the nanoantennas, so to make them resonant in both the visible (transversal resonance) and the infrared (longitudinal resonance), and by rotating the excitation field polarization to selectively take advantage of each resonance and achieve SERS and SEIRS on the same nanoantennas. As a proof of concept, we have fabricated gold nanoantennas by electron beam lithography on calcium difluoride (1-2 μm long, 60 nm wide, 60 nm high) that exhibit a transverse plasmonic resonance in the visible (640 nm) and a particularly strong longitudinal dipolar resonance in the infrared (tunable in the 1280-3100 cm -1 energy range as a function of the length). SERS and SEIRS detection of methylene blue molecules adsorbed on the nanoantenna\\'s surface is accomplished, with signal enhancement factors of 5 × 102 for SERS (electromagnetic enhancement) and up to 105 for SEIRS. Notably, we find that the field enhancement provided by the transverse resonance is sufficient to achieve SERS from single nanoantennas. Furthermore, we show that by properly tuning the nanoantenna length the signals of a multitude of vibrational modes can be enhanced with SEIRS. This simple concept of plasmonic nanosensor is highly suitable for integration on lab-on-a-chip schemes for label-free chemical and biomolecular identification with optimized performances. © 2013 American Chemical Society.

  10. 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®

  11. 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.

  12. Quantitative determination of the human breast milk macronutrients by near-infrared Raman spectroscopy

    Science.gov (United States)

    Motta, Edlene d. C. M.; Zângaro, Renato A.; Silveira, Landulfo, Jr.

    2012-03-01

    This work proposes the evaluation of the macronutrient constitution of human breast milk based on the spectral information provided by near-infrared Raman spectroscopy. Human breast milk (5 mL) from a subject was collected during the first two weeks of breastfeeding and stocked in -20°C freezer. Raman spectra were measured using a Raman spectrometer (830 nm excitation) coupled to a fiber based Raman probe. Spectra of human milk were dominated by bands of proteins, lipids and carbohydrates in the 600-1800 cm-1 spectral region. Raman spectroscopy revealed differences in the biochemical constitution of human milk depending on the time of breastfeeding startup. This technique could be employed to develop a classification routine for the milk in Human Milk Banking (HMB) depending on the nutritional facts.

  13. Measurement of rumen dry matter and neutral detergent fiber degradability of feeds by Fourier-transform infrared spectroscopy

    DEFF Research Database (Denmark)

    Belanche, A.; Weisbjerg, Martin Riis; Allison, G.G.

    2014-01-01

    This study explored the potential of partial least squares (PLS) and Fourier-transform infrared spectroscopy (FTIR) to predict rumen dry matter (DM) and neutral detergent fiber (NDF) degradation parameters of a wide range of feeds for ruminants, as an alternative to the in situ method. In total...... components, such as cellulose, pectin, lignin, cutin, and suberin, but also with nonstructural carbohydrates and certain active compounds. In conclusion, FTIR spectroscopy could be considered a low-cost alternative to in situ measurements in feed evaluation....

  14. Evaluation of flaA short variable region sequencing, multilocus sequence typing and Fourier transform infrared spectroscopy for discrimination between Campylobacter jejuni strains

    DEFF Research Database (Denmark)

    Josefsen, Mathilde Hartmann; Bonnichsen, Lise; Larsson, Jonas T.

    2012-01-01

    and Fourier transform infrared (FTIR) spectroscopy were applied on a collection of 102 epidemiologically related and unrelated Campylobacter jejuni strains. Previous application of FTIR spectroscopy for subtyping of Campylobacter has been limited. A subset of isolates, initially discriminated by flaA SVR...

  15. Non-invasive in situ identification and band assignments of diazepam, flunitrazepam and methadone hydrochloride with FT-near-infrared spectroscopy.

    Science.gov (United States)

    Ali, Hassan Refat H

    2011-03-20

    Near-infrared spectroscopy (NIR) has evolved into an important rapid, direct and non-invasive technique in drugs analysis. In this study, the suitability of NIR spectroscopy to identify two benzodiazepine derivatives, diazepam and flunitrazepam, and a synthetic opiate, methadone hydrochloride, inside USP vials and probe the solid-state form of diazepam presents in tablets has been explored. The results show the potential of NIR spectroscopy for rapid, in situ and non-destructive identification of drugs. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  16. State-of-art application of near infrared spectroscopy for functional diagnostics in neonatology

    International Nuclear Information System (INIS)

    Wolf, M.; Paiziev, A.

    2013-01-01

    The present brief review is devoted to application of near infra-red spectroscopy (NIRS) for early diagnostics of human brain injury. The number of commercially accessible NIRS instruments, and accordingly their users, increases but the precision of measurements and their reproducibility from the clinical point of view essentially depend on used algorithms, a kind of the NIRS-instrument, sensors, which frequently leads to the different values of the measurable parameters of blood oxygen saturation (StO 2 ). We present some commercially accessible NIRS instruments for control of an oxygen saturation degree in human blood, first of all in neonatology, on the basis of absorption and scattering of near infra-red light at human tissue chromophores. The results of clinical investigations of different NIRS-spectrometers for measurements of in-vivo new-born child' blood saturation are presented as well. (authors)

  17. FTIR spectroscopy applications in forensic science

    International Nuclear Information System (INIS)

    Roux, C.; Maynard, P.; Dawson, M.

    1999-01-01

    Infrared spectroscopy, and especially Fourier transform infrared spectroscopy, is a well-established technique in analytical chemistry and finds widespread application in qualitative and quantitative analyses. Infrared spectra depend on the nature of the functional groups present in the analyte, and are generally complex with numerous maxima and minima. These features are useful for comparison purposes and, in most cases, the infrared spectrum of an organic compound is considered as a unique functional print of this compound (i e the infrared spectrum constitutes the chemical signature or fingerprint of an organic compound). Many inorganic substances may also be uniquely identified using infrared spectroscopy. Until recently, infrared spectroscopy was of only limited utility in forensic science, despite its high selectivity. This is because infrared spectroscopy suffered from a lack of sensitivity in its early forms. However, with the advance of modern technology this is no longer the case. The widespread use of microscope attachments, along with numerous new sampling accessories, has overcome most of the previous limitations. For example, with an infrared microscope, it is possible to focus the infrared beam, and therefore select relevant areas of the sample as small as 10 x 10 μm and achieve a measurement in situ. Such a configuration enables the rapid generation of high-resolution spectra from samples of 10 ng. Typical forensic applications include the analysis of single textile fibres, minute paint chips or smears, drugs, laser printer and photocopy toners, polymers and miscellaneous unknown substances. Here we will broadly review the most common applications of infrared spectroscopy in forensic science

  18. Pharmaceutical Raw Material Identification Using Miniature Near-Infrared (MicroNIR) Spectroscopy and Supervised Pattern Recognition Using Support Vector Machine

    OpenAIRE

    Sun, Lan; Hsiung, Chang; Pederson, Christopher G.; Zou, Peng; Smith, Valton; von Gunten, Marc; O?Brien, Nada A.

    2016-01-01

    Near-infrared spectroscopy as a rapid and non-destructive analytical technique offers great advantages for pharmaceutical raw material identification (RMID) to fulfill the quality and safety requirements in pharmaceutical industry. In this study, we demonstrated the use of portable miniature near-infrared (MicroNIR) spectrometers for NIR-based pharmaceutical RMID and solved two challenges in this area, model transferability and large-scale classification, with the aid of support vector machin...

  19. 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.

  20. 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...

  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. Comparison between proton transfer reaction mass spectrometry and near infrared spectroscopy for the authentication of Brazilian coffee

    NARCIS (Netherlands)

    Monteiro, Pablo Inocêncio; Santos, Jânio Sousa; Alvarenga Brizola, Vitor Rafael; Pasini Deolindo, Carolina Turnes; Koot, Alex; Boerrigter-Eenling, Rita; Ruth, van Saskia; Georgouli, Konstantia; Koidis, Anastasios; Granato, Daniel

    2018-01-01

    In this study, proton-transfer reaction mass spectrometry (PTR-MS) and near-infrared spectroscopy (NIRS) were compared for the authentication of geographical and farming system origins of Brazilian coffees. For this purpose, n = 19 organic (ORG) and n = 26 conventional (CONV) coffees from

  3. 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

  4. Structure and acidity of individual Fluid Catalytic Cracking catalyst particles studied by synchrotron-based infrared micro-spectroscopy

    NARCIS (Netherlands)

    Buurmans, I.L.C.; Soulimani, F.; Ruiz Martinez, J.; van der Bij, H.E.; Weckhuysen, B.M.

    2013-01-01

    A synchrotron-based infrared micro-spectroscopy study has been conducted to investigate the structure as well as the Brønsted and Lewis acidity of Fluid Catalytic Cracking (FCC) catalyst particles at the individual particle level. Both fresh and laboratory-deactivated catalyst particles have been

  5. Frontal lobe activation during object permanence: data from near-infrared spectroscopy.

    Science.gov (United States)

    Baird, Abigail A; Kagan, Jerome; Gaudette, Thomas; Walz, Kathryn A; Hershlag, Natalie; Boas, David A

    2002-08-01

    The ability to create and hold a mental schema of an object is one of the milestones in cognitive development. Developmental scientists have named the behavioral manifestation of this competence object permanence. Convergent evidence indicates that frontal lobe maturation plays a critical role in the display of object permanence, but methodological and ethical constrains have made it difficult to collect neurophysiological evidence from awake, behaving infants. Near-infrared spectroscopy provides a noninvasive assessment of changes in oxy- and deoxyhemoglobin and total hemoglobin concentration within a prescribed region. The evidence described in this report reveals that the emergence of object permanence is related to an increase in hemoglobin concentration in frontal cortex.

  6. Estimation of muscle fatigue using surface electromyography and near-infrared spectroscopy.

    Science.gov (United States)

    Taelman, Joachim; Vanderhaegen, Joke; Robijns, Mieke; Naulaers, Gunnar; Spaepen, Arthur; Van Huffel, Sabine

    2011-01-01

    This study looks at various parameters, derived from surface electromyography (sEMG) and Near Infrared Spectroscopy (NIRS) and their relationship in muscle fatigue during a static elbow flexion until exhaustion as well as during a semidynamic exercise.We found a linear increasing trend for a corrected amplitude parameter and a linear decreasing slope for the frequency content of the sEMG signal. The tissue oxygenation index (TOI) extracted from NIRS recordings showed a four-phase response for all the subjects. A strong correlation between frequency content of the sEMG signal and TOI was established. We can conclude that both sEMG and NIRS give complementary information concerning muscle fatigue.

  7. Digital Breast Tomosynthesis guided Near Infrared Spectroscopy: Volumetric estimates of fibroglandular fraction and breast density from tomosynthesis reconstructions.

    Science.gov (United States)

    Vedantham, Srinivasan; Shi, Linxi; Michaelsen, Kelly E; Krishnaswamy, Venkataramanan; Pogue, Brian W; Poplack, Steven P; Karellas, Andrew; Paulsen, Keith D

    A multimodality system combining a clinical prototype digital breast tomosynthesis with its imaging geometry modified to facilitate near-infrared spectroscopic imaging has been developed. The accuracy of parameters recovered from near-infrared spectroscopy is dependent on fibroglandular tissue content. Hence, in this study, volumetric estimates of fibroglandular tissue from tomosynthesis reconstructions were determined. A kernel-based fuzzy c-means algorithm was implemented to segment tomosynthesis reconstructed slices in order to estimate fibroglandular content and to provide anatomic priors for near-infrared spectroscopy. This algorithm was used to determine volumetric breast density (VBD), defined as the ratio of fibroglandular tissue volume to the total breast volume, expressed as percentage, from 62 tomosynthesis reconstructions of 34 study participants. For a subset of study participants who subsequently underwent mammography, VBD from mammography matched for subject, breast laterality and mammographic view was quantified using commercial software and statistically analyzed to determine if it differed from tomosynthesis. Summary statistics of the VBD from all study participants were compared with prior independent studies. The fibroglandular volume from tomosynthesis and mammography were not statistically different ( p =0.211, paired t-test). After accounting for the compressed breast thickness, which were different between tomosynthesis and mammography, the VBD from tomosynthesis was correlated with ( r =0.809, p 0.99, paired t-test), and was linearly related to, the VBD from mammography. Summary statistics of the VBD from tomosynthesis were not statistically different from prior studies using high-resolution dedicated breast computed tomography. The observation of correlation and linear association in VBD between mammography and tomosynthesis suggests that breast density associated risk measures determined for mammography are translatable to tomosynthesis

  8. Potential role of the nitroacidium ion on HONO emissions from the snowpack.

    Science.gov (United States)

    Hellebust, Stig; Roddis, Tristan; Sodeau, John R

    2007-02-22

    The effects of photolysis on frozen, thin films of water-ice containing nitrogen dioxide (as its dimer dinitrogen tetroxide) have been investigated using a combination of Fourier transform reflection-absorption infrared (FT-RAIR) spectroscopy and mass spectrometry. The release of HONO is ascribed to a mechanism in which nitrosonium nitrate (NO+NO3-) is formed. Subsequent solvation of the cation leads to the nitroacidium ion, H2ONO+, i.e., protonated nitrous acid. The pathway proposed explains why the field measurement of HONO at different polar sites is often contradictory.

  9. Spectroscopic analysis of bladder cancer tissues using Fourier transform infrared spectroscopy

    Science.gov (United States)

    Al-Muslet, Nafie A.; Ali, Essam E.

    2012-03-01

    Bladder cancer is one of the most common cancers in Africa. It takes several days to reach a diagnosis using histological examinations of specimens obtained by endoscope, which increases the medical expense. Recently, spectroscopic analysis of bladder cancer tissues has received considerable attention as a diagnosis technique due to its sensitivity to biochemical variations in the samples. This study investigated the use of Fourier transform infrared (FTIR) spectroscopy to analyze a number of bladder cancer tissues. Twenty-two samples were collected from 11 patients diagnosed with bladder cancer from different hospitals without any pretreatment. From each patient two samples were collected, one normal and another cancerous. FTIR spectrometer was used to differentiate between normal and cancerous bladder tissues via changes in spectra of these samples. The investigations detected obvious changes in the bands of proteins (1650, 1550 cm-1), lipids (2925, 2850 cm-1), and nucleic acid (1080, 1236 cm-1). The results show that FTIR spectroscopy is promising as a rapid, accurate, nondestructive, and easy to use alternative method for identification and diagnosis of bladder cancer tissues.

  10. The didatic model in teaching french as a foreign language: a study of the genre Itinéraire de Voyage O modelo didático no ensino do francês língua estrangeira: um estudo do gênero Itinéraire de Voyage

    Directory of Open Access Journals (Sweden)

    Luiza Guimarães Santos

    2012-04-01

    Full Text Available This paper aims to show the relevance of teaching French as a foreign language through text genres, especially if we assume that the perspective adopted is one that privileges the action in a foreign language. In addition, we aim to reflect about the importance of knowing a genre before teaching how to produce it as well as point some difficulties involved in the elaboration of a didactic model, particularly when working with foreign languages. Therefore, we will analyze the genre itinéraire de voyage, and from observation of several texts of the same genre, we will elaborate a didactic model of this genre, as presented by Schneuwly and Dolz (2004. The theoretical basis of this study relies on the work of Schneuwly and Dolz (2004 and Bronckart (1999, 2004, 2006 for the definition of textual genres and the elaboration of a didactic model of the genre itinéraire de voyage. The didactic model of a genre is a collection of the characteristics of its teachable dimensions and is one of the steps towards the adoption of genres as a teaching object. Once completed, the didactic model can be used as a teaching tool for the teacher to choose what he/she will teach and how.Este trabalho tem por objetivo mostrar a relevância de se ensinar o francês como língua estrangeira, por meio dos gêneros textuais, especialmente, se assumimos que a perspectiva adotada é aquela que privilegia o agir em língua estrangeira. Ademais, almejamos refletir sobre a importância de se conhecer bem um gênero, antes de ensinar a produzi-lo e sobre as dificuldades envolvidas na elaboração do modelo didático de um gênero, particularmente, quando trabalhamos com línguas estrangeiras. Para tanto, relataremos nossa experiência, ao elaborar o modelo didático do gênero textual itinéraire de voyage, feito a partir da observação de diversos textos do mesmo gênero e conforme apresentado por Schneuwly e Dolz (2004. A fundamentação teórica deste estudo apoia-se nos

  11. Breaking through the glass ceiling: The correlation between the self-diffusivity in and krypton permeation through deeply supercooled liquid nanoscale methanol films

    Science.gov (United States)

    Smith, R. Scott; Matthiesen, Jesper; Kay, Bruce D.

    2010-03-01

    Molecular beam techniques, temperature-programmed desorption (TPD), and reflection absorption infrared spectroscopy (RAIRS) are used to explore the relationship between krypton permeation through and the self-diffusivity of supercooled liquid methanol at temperatures (100-115 K) near the glass transition temperature, Tg (103 K). Layered films, consisting of CH3OH and CD3OH, are deposited on top of a monolayer of Kr on a graphene covered Pt(111) substrate at 25 K. Concurrent Kr TPD and RAIRS spectra are acquired during the heating of the composite film to temperatures above Tg. The CO vibrational stretch is sensitive to the local molecular environment and is used to determine the supercooled liquid diffusivity from the intermixing of the isotopic layers. We find that the Kr permeation and the diffusivity of the supercooled liquid are directly and quantitatively correlated. These results validate the rare-gas permeation technique as a tool for probing the diffusivity of supercooled liquids.

  12. Methane dissociation on the steps and terraces of Pt(211) resolved by quantum state and impact site

    Science.gov (United States)

    Chadwick, Helen; Guo, Han; Gutiérrez-González, Ana; Menzel, Jan Paul; Jackson, Bret; Beck, Rainer D.

    2018-01-01

    Methane dissociation on the step and terrace sites of a Pt(211) single crystal was studied by reflection absorption infrared spectroscopy (RAIRS) at a surface temperature of 120 K. The C—H stretch RAIRS signal of the chemisorbed methyl product species was used to distinguish between adsorption on step and terrace sites allowing methyl uptake to be monitored as a function of incident kinetic energy for both sites. Our results indicate a direct dissociation mechanism on both sites with higher reactivity on steps than on terraces consistent with a difference in an activation barrier height of at least 30 kJ/mol. State-specific preparation of incident CH4 with one quantum of antisymmetric (ν3) stretch vibration further increases the CH4 reactivity enabling comparison between translational and vibrational activation on both steps and terraces. The reaction is modeled with first principles quantum theory that accurately describes dissociative chemisorption at different sites on the surface.

  13. High-Resolution Infrared Spectroscopy of Imidazole Clusters in Helium Droplets Using Quantum Cascade Lasers

    Science.gov (United States)

    Mani, Devendra; Can, Cihad; Pal, Nitish; Schwaab, Gerhard; Havenith, Martina

    2017-06-01

    Imidazole ring is a part of many biologically important molecules and drugs. Imidazole monomer, dimer and its complexes with water have earlier been studied using infrared spectroscopy in helium droplets^{1,2} and molecular beams^{3}. These studies were focussed on the N-H and O-H stretch regions, covering the spectral region of 3200-3800 \\wn. We have extended the studies on imidazole clusters into the ring vibration region. The imidazole clusters were isolated in helium droplets and were probed using a combination of infrared spectroscopy and mass spectrometry. The spectra in the region of 1000-1100 \\wn and 1300-1460 \\wn were recorded using quantum cascade lasers. Some of the observed bands could be assigned to imidazole monomer and higher order imidazole clusters, using pickup curve analysis and ab initio calculations. Work is still in progress. The results will be discussed in detail in the talk. References: 1) M.Y. Choi and R.E. Miller, J. Phys. Chem. A, 110, 9344 (2006). 2) M.Y. Choi and R.E. Miller, Chem. Phys. Lett., 477, 276 (2009). 3) J. Zischang, J. J. Lee and M. Suhm, J. Chem. Phys., 135, 061102 (2011). Note: This work was supported by the Cluster of Excellence RESOLV (Ruhr-Universitat EXC1069) funded by the Deutsche Forschungsgemeinschaft.

  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. 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.

  16. Infrared spectroscopy of the mineralogy of coprolites from Brean Down: evidence of past human activities and animal husbandry

    Science.gov (United States)

    Allen, Samantha D. M.; Almond, Matthew J.; Bell, Martin G.; Hollins, Peter; Marks, Sonja; Mortimore, Joanne L.

    2002-03-01

    The mineralogy of 11 concretions from the Bronze Age settlement horizons at Brean Down near Weston-super-Mare, Somerset, UK, has been examined by infrared spectroscopy. The concretions are found to contain calcite and apatite and, in some cases, quartz. Four further concretions from the later Iron Age Meare Village, soil samples from Brean Down and mineralised samples of known faecal origin from a cesspit within the Tudor Merchant's house in Tenby have been similarly examined. It is found that all samples contain calcite, but only the concretions and the Tenby cesspit samples contain apatite. None of the soil samples contain apatite, although these are relatively high in quartz. This suggests that the concretions are coprolites and that the apatite has a biological origin in small bone fragments. The infrared study is backed up by scanning electron microscopy which confirms the presence of phosphorus in the coprolite samples and shows a morphology suggestive of the presence of bone fragments; it is likely, therefore, that the coprolites result from a carnivore—most probably from dogs. The findings show the usefulness of infrared spectroscopy for the rapid identification of mineralised coprolitic material from archaeological sites.

  17. Capturing Pain in the Cortex during General Anesthesia: Near Infrared Spectroscopy Measures in Patients Undergoing Catheter Ablation of Arrhythmias.

    Directory of Open Access Journals (Sweden)

    Barry D Kussman

    Full Text Available The predictability of pain makes surgery an ideal model for the study of pain and the development of strategies for analgesia and reduction of perioperative pain. As functional near-infrared spectroscopy reproduces the known functional magnetic resonance imaging activations in response to a painful stimulus, we evaluated the feasibility of functional near-infrared spectroscopy to measure cortical responses to noxious stimulation during general anesthesia. A multichannel continuous wave near-infrared imager was used to measure somatosensory and frontal cortical activation in patients undergoing catheter ablation of arrhythmias under general anesthesia. Anesthetic technique was standardized and intraoperative NIRS signals recorded continuously with markers placed in the data set for the timing and duration of each cardiac ablation event. Frontal cortical signals only were suitable for analysis in five of eight patients studied (mean age 14 ± 1 years, weight 66.7 ± 17.6 kg, 2 males. Thirty ablative lesions were recorded for the five patients. Radiofrequency or cryoablation was temporally associated with a hemodynamic response function in the frontal cortex characterized by a significant decrease in oxyhemoglobin concentration (paired t-test, p<0.05 with the nadir occurring in the period 4 to 6 seconds after application of the ablative lesion. Cortical signals produced by catheter ablation of arrhythmias in patients under general anesthesia mirrored those seen with noxious stimulation in awake, healthy volunteers, during sedation for colonoscopy, and functional Magnetic Resonance Imaging activations in response to pain. This study demonstrates the feasibility and potential utility of functional near-infrared spectroscopy as an objective measure of cortical activation under general anesthesia.

  18. Evaluating RNAlater® as a preservative for using near-infrared spectroscopy to predict Anopheles gambiae age and species

    Science.gov (United States)

    Mosquito age and species identification is a crucial determinant of the efficacy of vector control programs. Near-infrared spectroscopy (NIRS) has previously been applied successfully to rapidly, non-destructively, and simultaneously determine the age and species of freshly anesthetized African mala...

  19. A sampling approach for predicting the eating quality of apples using visible–near infrared spectroscopy

    DEFF Research Database (Denmark)

    Vega, Mabel V Martínez; Sharifzadeh, Sara; Wulfsohn, Dvoralai

    2013-01-01

    BACKGROUND Visible–near infrared spectroscopy remains a method of increasing interest as a fast alternative for the evaluation of fruit quality. The success of the method is assumed to be achieved by using large sets of samples to produce robust calibration models. In this study we used represent......BACKGROUND Visible–near infrared spectroscopy remains a method of increasing interest as a fast alternative for the evaluation of fruit quality. The success of the method is assumed to be achieved by using large sets of samples to produce robust calibration models. In this study we used...... representative samples of an early and a late season apple cultivar to evaluate model robustness (in terms of prediction ability and error) on the soluble solids content (SSC) and acidity prediction, in the wavelength range 400–1100 nm. RESULTS A total of 196 middle–early season and 219 late season apples (Malus...... training and test sets (‘smooth fractionator’, by date of measurement after harvest and random). Using the ‘smooth fractionator’ sampling method, fewer spectral bands (26) and elastic net resulted in improved performance for SSC models of ‘Aroma’ apples, with a coefficient of variation CVSSC = 13...

  20. Near Infrared Spectroscopy Detection and Quantification of Herbal Medicines Adulterated with Sibutramine.

    Science.gov (United States)

    da Silva, Neirivaldo Cavalcante; Honorato, Ricardo Saldanha; Pimentel, Maria Fernanda; Garrigues, Salvador; Cervera, Maria Luisa; de la Guardia, Miguel

    2015-09-01

    There is an increasing demand for herbal medicines in weight loss treatment. Some synthetic chemicals, such as sibutramine (SB), have been detected as adulterants in herbal formulations. In this study, two strategies using near infrared (NIR) spectroscopy have been developed to evaluate potential adulteration of herbal medicines with SB: a qualitative screening approach and a quantitative methodology based on multivariate calibration. Samples were composed by products commercialized as herbal medicines, as well as by laboratory adulterated samples. Spectra were obtained in the range of 14,000-4000 per cm. Using PLS-DA, a correct classification of 100% was achieved for the external validation set. In the quantitative approach, the root mean squares error of prediction (RMSEP), for both PLS and MLR models, was 0.2% w/w. The results prove the potential of NIR spectroscopy and multivariate calibration in quantifying sibutramine in adulterated herbal medicines samples. © 2015 American Academy of Forensic Sciences.

  1. Near-infrared spectroscopy can reveal increases in brain activity related to animal-assisted therapy

    OpenAIRE

    Morita, Yuka; Ebara, Fumio; Morita, Yoshimitsu; Horikawa, Etsuo

    2017-01-01

    [Purpose] Previous studies have indicated that animal-assisted therapy can promote recovery of psychological, social, and physiological function in mental disorders. This study was designed as a pilot evaluation of the use of near-infrared spectroscopy to objectively identify changes in brain activity that could mediate the effect of animal-assisted therapy. [Subjects and Methods] The participants were 20 healthy students (10 males and 10 females; age 19?21 years) of the Faculty of Agricultur...

  2. 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.

  3. 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

  4. Investigation of carbonates in the Sutter's Mill meteorite grains with hyperspectral infrared imaging micro-spectroscopy

    Science.gov (United States)

    Yesiltas, Mehmet

    2018-04-01

    Synchrotron-based high spatial resolution hyperspectral infrared imaging technique provides thousands of infrared spectra with high resolution, thus allowing us to acquire detailed spatial maps of chemical molecular structures for many grains in short times. Utilizing this technique, thousands of infrared spectra were analyzed at once instead of inspecting each spectrum separately. Sutter's Mill meteorite is a unique carbonaceous type meteorite with highly heterogeneous chemical composition. Multiple grains from the Sutter's Mill meteorite have been studied using this technique and the presence of both hydrous and anhydrous silicate minerals have been observed. It is observed that the carbonate mineralogy varies from simple to more complex carbonates even within a few microns in the meteorite grains. These variations, the type and distribution of calcite-like vs. dolomite-like carbonates are presented by means of hyperspectral FTIR imaging spectroscopy with high resolution. Various scenarios for the formation of different carbonate compositions in the Sutter's Mill parent body are discussed.

  5. Monitoring ultraviolet (UV) radiation inactivation of Cronobacter sakazakii in dry infant formula using Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Liu, Qian; Lu, Xiaonan; Swanson, Barry G; Rasco, Barbara A; Kang, Dong-Hyun

    2012-01-01

    Cronobacter sakazakii is an opportunistic pathogen associated with dry infant formula presenting a high risk to low birth weight neonates. The inactivation of C. sakazakii in dry infant formula by ultraviolet (UV) radiation alone and combined with hot water treatment at temperatures of 55, 60, and 65 °C were applied in this study. UV radiation with doses in a range from 12.1 ± 0.30 kJ/m² to 72.8 ± 1.83 kJ/m² at room temperature demonstrated significant inactivation of C. sakazakii in dry infant formula (P radiation combining 60 °C hot water treatment increased inactivation of C. sakazakii cells significantly (P radiation on C. sakazakii inactivation kinetics (D value) were not observed in infant formula reconstituted in 55 and 65 °C water (P > 0.05). The inactivation mechanism was investigated using vibrational spectroscopy. Infrared spectroscopy detected significant stretching mode changes of macromolecules on the basis of spectral features, such as DNA, proteins, and lipids. Minor changes on cell membrane composition of C. sakazakii under UV radiation could be accurately and correctly monitored by infrared spectroscopy coupled with 2nd derivative transformation and principal component analysis. © 2011 Institute of Food Technologists®

  6. 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.

  7. 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).

  8. Use of in-line near-infrared spectroscopy in combination with chemometrics for improved understanding of pharmaceutical processes

    DEFF Research Database (Denmark)

    Rantanen, Jukka; Wikström, Håkan; Turner, Rebecca

    2005-01-01

    was extracted. Principal component loadings were fully interpreted to validate the conclusions drawn from scores and predictions. Thus NIR spectroscopy could be used to determine the end points of the three subphases of high shear wet granulation and, as such, provide a fast in-line quality control tool....... solid dosage form. In this study, the use of in-line near-infrared (NIR) spectroscopy as a process analytical tool for high shear granulation was investigated. In combination with principal component-based methods, process analysis of three separate phases of high shear wet granulation (mixing, spraying...

  9. 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

  10. [Current progress in food geographical origin traceability by near infrared spectroscopy technology].

    Science.gov (United States)

    Ma, Dong-Hong; Wang, Xi-Chang; Liu, Li-Ping; Liu, Yuan

    2011-04-01

    The geographical origin traceability of food, an important part of traceability system, is effective in protecting the quality and safety of foodstuffs. Near-infrared spectroscopy (NIR), which is a powerful technique for geographical origin traceability, has attracted extensive attention by scientists due to its speediness, non-pollution and simple operation. This paper presents the advantages and disadvantages of techniques that have been used for food geographical origin traceability. The basic principles of NIR and its applications in different food geographical origin traceability are presented too. Furthermore, problems in applications are analyzed and the future development trends are discussed.

  11. Quantitative determination of additive Chlorantraniliprole in Abamectin preparation: Investigation of bootstrapping soft shrinkage approach by mid-infrared spectroscopy

    Science.gov (United States)

    Yan, Hong; Song, Xiangzhong; Tian, Kuangda; Chen, Yilin; Xiong, Yanmei; Min, Shungeng

    2018-02-01

    A novel method, mid-infrared (MIR) spectroscopy, which enables the determination of Chlorantraniliprole in Abamectin within minutes, is proposed. We further evaluate the prediction ability of four wavelength selection methods, including bootstrapping soft shrinkage approach (BOSS), Monte Carlo uninformative variable elimination (MCUVE), genetic algorithm partial least squares (GA-PLS) and competitive adaptive reweighted sampling (CARS) respectively. The results showed that BOSS method obtained the lowest root mean squared error of cross validation (RMSECV) (0.0245) and root mean squared error of prediction (RMSEP) (0.0271), as well as the highest coefficient of determination of cross-validation (Qcv2) (0.9998) and the coefficient of determination of test set (Q2test) (0.9989), which demonstrated that the mid infrared spectroscopy can be used to detect Chlorantraniliprole in Abamectin conveniently. Meanwhile, a suitable wavelength selection method (BOSS) is essential to conducting a component spectral analysis.

  12. Adding a dimension to the infrared spectra of interfaces: 2D SFG spectroscopy via mid-IR pulse shaping

    Science.gov (United States)

    Zanni, Martin

    2012-02-01

    Sum-frequency generation spectroscopy provides an infrared spectrum of interfaces and thus has widespread use in the materials and chemical sciences. In this presentation, I will present our recent work in developing a 2D pulse sequence to generate 2D SFG spectra of interfaces, in analogy to 2D infrared spectra used to measure bulk species. To develop this spectroscopy, we have utilized many of the tricks-of-the-trade developed in the 2D IR and 2D Vis communities in the last decade, including mid-IR pulse shaping. With mid-IR pulse shaping, the 2D pulse sequence is manipulated by computer programming in the desired frequency resolution, rotating frame, and signal pathway. We believe that 2D SFG will become an important tool in the interfacial sciences in an analogous way that 2D IR is now being used in many disciplines.

  13. Shelf life study of egg albumin in pasteurized and non-pasteurized eggs using visible-near infrared spectroscopy

    Science.gov (United States)

    A twelve week shelf life study was conducted on the egg albumen from both pasteurized and non-pasteurized shell eggs using visible-near infrared spectroscopy. The goal of the study was to correlate the chemical changes detected in the spectra to the measurement of Haugh units (measure of interior eg...

  14. Exploring the Dynamics of Superconductors by Time-Resolved Far-Infrared Spectroscopy

    International Nuclear Information System (INIS)

    Carr, G. L.; Lobo, R. P. S. M.; LaVeigne, J.; Reitze, D. H.; Tanner, D. B.

    2000-01-01

    We have examined the recombination of excess quasiparticles in superconducting Pb by time-resolved far-infrared spectroscopy using a pulsed synchrotron source. The energy gap shift calculated by Owen and Scalapino [Phys. Rev. Lett. 28, 1559 (1972)] is directly observed, as is the associated reduction in the Cooper pair density. The relaxation process involves a two-component decay; the faster (∼200 ps) is associated with the actual (effective) recombination process, while the slower (∼10 to 100ns) is due to heat transport across the film/substrate interface. The temperature dependence of the recombination process between 0.5T c and 0.85T c is in good agreement with theory

  15. [Discrimination of Rice Syrup Adulterant of Acacia Honey Based Using Near-Infrared Spectroscopy].

    Science.gov (United States)

    Zhang, Yan-nan; Chen, Lan-zhen; Xue, Xiao-feng; Wu, Li-ming; Li, Yi; Yang, Juan

    2015-09-01

    At present, the rice syrup as a low price of the sweeteners was often adulterated into acacia honey and the adulterated honeys were sold in honey markets, while there is no suitable and fast method to identify honey adulterated with rice syrup. In this study, Near infrared spectroscopy (NIR) combined with chemometric methods were used to discriminate authenticity of honey. 20 unprocessed acacia honey samples from the different honey producing areas, mixed? with different proportion of rice syrup, were prepared of seven different concentration gradient? including 121 samples. The near infrared spectrum (NIR) instrument and spectrum processing software have been applied in the? spectrum? scanning and data conversion on adulterant samples, respectively. Then it was analyzed by Principal component analysis (PCA) and canonical discriminant analysis methods in order to discriminating adulterated honey. The results showed that after principal components analysis, the first two principal components accounted for 97.23% of total variation, but the regionalism of the score plot of the first two PCs was not obvious, so the canonical discriminant analysis was used to make the further discrimination, all samples had been discriminated correctly, the first two discriminant functions accounted for 91.6% among the six canonical discriminant functions, Then the different concentration of adulterant samples can be discriminated correctly, it illustrate that canonical discriminant analysis method combined with NIR spectroscopy is not only feasible but also practical for rapid and effective discriminate of the rice syrup adulterant of acacia honey.

  16. Study on Fracture Healing with Small-Splint-Fixation Therapy by Near-Infrared Raman Spectroscopy

    OpenAIRE

    Hao Huang; Shangyuan Feng; Weiwei Chen; Yun Yu; Duo Lin; Rong Chen

    2013-01-01

    In this study, near-infrared (NIR) Raman spectroscopy was explored to assess the incorporation of calcium hydroxyapatite (CHA ~960 cm−1) and other biochemical substances during the recovery of rabbits with complete radial fractures treated with or without small splints. 24 rabbits were randomy divided into two groups, one treated with small-splint-fixation therapy and the other without any intervention. The rabbits were sacrificed at 7, 15, 23, and 30 days after surgery, and the surface layer...

  17. Near-infrared spectroscopy can detect differences in vascular responsiveness to a hyperglycaemic challenge in individuals with obesity compared to normal-weight individuals.

    Science.gov (United States)

    Soares, Rogério Nogueira; Reimer, Raylene A; Alenezi, Zaid; Doyle-Baker, Patricia K; Murias, Juan Manuel

    2018-01-01

    To examine whether the near-infrared spectroscopy combined with vascular occlusion test technique could detect differences in vascular responsiveness during hyperglycaemia between normal-weight individuals and individuals with obesity. A total of 16 normal-weight individuals (body mass index, 21.3 ± 1.7 kg/m 2 ) and 13 individuals with obesity (body mass index, 34.4 ± 2.0 kg/m 2 ) were submitted to five vascular occlusion tests (Pre, 30, 60, 90 and 120 min after glucose challenge). Vascular responsiveness was determined by the Slope 2 (Slope 2 StO 2 ) and the area under the curve (StO 2AUC ) of oxygen saturation derived from near-infrared spectroscopy-vascular occlusion test. The Slope 2 StO 2 increased from 1.07 ± 0.16%/s (Pre) to 1.53 ± 0.21%/s at 90 min ( p obese it increased from 0.71 ± 0.09%/s (Pre) to 0.92 ± 0.14%/s at 60 min ( p obesity. Near-infrared spectroscopy-vascular occlusion test technique was capable of detecting differences in vascular responsiveness during hyperglycaemia between normal-weight individuals and individuals with obesity.

  18. Characterization of Campylobacter jejuni applying flaA short variable region sequencing, multilocus sequencing and Fourier transform infrared spectroscopy

    DEFF Research Database (Denmark)

    Josefsen, Mathilde Hartmann; Bonnichsen, Lise; Larsson, Jonas

    flaA short variable region sequencing and phenetic Fourier transform infrared (FTIR) spectroscopy was applied on a collection of 102 Campylobacter jejuni isolated from continuous sampling of organic, free range geese and chickens. FTIR has been shown to serve as a valuable tool in typing...

  19. 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...

  20. Le règlement de compte littéraire au siècle d’or : quand la fiction doit détruire la réalité

    Directory of Open Access Journals (Sweden)

    Florence Dumora

    2009-10-01

    Full Text Available Cet article propose l’étude des rapports entre un auteur original et un auteur apocryphe, tels qu’ils s’expriment au sein de la fiction elle-même. La littérature espagnole du Siècle d’Or offre deux cas aussi remarquables que connus de cette situation littéraire – Don Quijote de la Mancha (1605 et 1615 et Guzmán de Alfarache (1599 et 1604 – où la fiction devient le double lieu de l’invention narrative et de la critique de l’apocryphe, médiatisée et permise par les éléments propres à la technique narrative mais tirés aussi de la réalité éditoriale que constitue l’imposture : les deux œuvres se composent de deux parties, et par là même fonctionnent de façon spéculaire non seulement par rapport à elles-mêmes mais aussi par rapport aux textes apocryphes qui furent élaborés et publiés entre les deux parties de l’original. Cette imbrication donne au fait littéraire une dimension métalittéraire et scelle le statut de l’auteur authentique par rapport à l’apocryphe, qui n’en demeure pas moins auteur pour la postérité.

  1. 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.

  2. Infrared photoexcitation spectroscopy of conducting polymer and C60 composites: direct evidence of photo-induced electron transfer

    NARCIS (Netherlands)

    Lee, Kwanghee; Janssen, R.A.J.; Sariciftci, N.S.; Heeger, A.J.

    1994-01-01

    We report direct spectral evidence of photoinduced electron transfer from the excited state of conducting polymer onto C60 by infrared photoexcitation spectroscopy, from 0.01 eV (100 cm-1) to 1.3 eV (11,000 cm-1). The photoinduced absorption spectra of poly(3-octylthiophene) (P30T) and

  3. Far-infrared vibrational modes of DNA components studied by terahertz time-domain spectroscopy

    International Nuclear Information System (INIS)

    Fischer, B M; Walther, M; Jepsen, P Uhd

    2002-01-01

    The far-infrared dielectric function of a wide range of organic molecules is dominated by vibrations involving a substantial fraction of the atoms forming the molecule and motion associated with intermolecular hydrogen bond vibrations. Due to their collective nature such modes are highly sensitive to the intra- and intermolecular structure and thus provide a unique fingerprint of the conformational state of the molecule and effects of its environment. We demonstrate the use of terahertz time-domain spectroscopy (THz-TDS) for recording the far-infrared (0.5-4.0 THz) dielectric function of the four nucleobases and corresponding nucleosides forming the building blocks of deoxyribose nucleic acid (DNA). We observe numerous distinct spectral features with large differences between the molecules in both frequency-dependent absorption coefficient and index of refraction. Assisted by results from density-functional calculations we interpret the origin of the observed resonances as vibrations of hydrogen bonds between the molecules

  4. Comprehensive two-dimensional liquid chromatography with on-line Fourier-transform-infrared-spectroscopy detection for the characterization of copolymers

    NARCIS (Netherlands)

    Kok, S.J.; Hankemeier, T.; Schoenmakers, P.J.

    2005-01-01

    The on-line coupling of comprehensive two-dimensional liquid chromatography (liquid chromatography × size-exclusion chromatography, LC × SEC) and infrared (IR) spectroscopy has been realized by means of an IR flow cell. The system has been assessed by the functional-group analysis of a series of

  5. 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.

  6. 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.

  7. WIRELESS DISTRIBUTED ACQUISITION SYSTEM FOR NEAR INFRARED SPECTROSCOPY – WDA-NIRS

    Directory of Open Access Journals (Sweden)

    J. SAFAIE

    2013-07-01

    Full Text Available The wireless distributed acquisition system for near infrared spectroscopy (WDA-NIRS is a portable, ultra-compact, continuous wave (CW NIRS system. Its main advantage is that it allows continuous synchronized multi-site hemodynamic monitoring. The WDA-NIRS system calculates online changes in hemoglobin concentration based on modified Beer–Lambert law and the tissue oxygenation index based on the spatial-resolved spectroscopy method. It consists of up to seven signal acquisition units, sufficiently small to be easily attached to any part of the body. These units are remotely synchronized by a PC base station for independent acquisition of NIRS signals. Each acquisition module can be freely adapted to individual requirements such as local skin properties and the microcirculation of interest, e.g., different muscles, brain, skin, etc. For this purpose, the light emitted by each LED can be individually, interactively or automatically adjusted to local needs. Furthermore, the user can freely create an emitter time-multiplexing protocol and choose the detector sensitivity most suitable to a particular situation. The potential diagnostic value of this advanced device is demonstrated by three typical applications.

  8. Classification of structurally related commercial contrast media by near infrared spectroscopy.

    Science.gov (United States)

    Yip, Wai Lam; Soosainather, Tom Collin; Dyrstad, Knut; Sande, Sverre Arne

    2014-03-01

    Near infrared spectroscopy (NIRS) is a non-destructive measurement technique with broad application in pharmaceutical industry. Correct identification of pharmaceutical ingredients is an important task for quality control. Failure in this step can result in several adverse consequences, varied from economic loss to negative impact on patient safety. We have compared different methods in classification of a set of commercially available structurally related contrast media, Iodixanol (Visipaque(®)), Iohexol (Omnipaque(®)), Caldiamide Sodium and Gadodiamide (Omniscan(®)), by using NIR spectroscopy. The performance of classification models developed by soft independent modelling of class analogy (SIMCA), partial least squares discriminant analysis (PLS-DA) and Main and Interactions of Individual Principal Components Regression (MIPCR) were compared. Different variable selection methods were applied to optimize the classification models. Models developed by backward variable elimination partial least squares regression (BVE-PLS) and MIPCR were found to be most effective for classification of the set of contrast media. Below 1.5% of samples from the independent test set were not recognized by the BVE-PLS and MIPCR models, compared to up to 15% when models developed by other techniques were applied. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Advances in R&D in near-infrared spectroscopy in Japan

    Science.gov (United States)

    Kawano, Sumio; Iwamoto, Mutsuo

    1991-02-01

    More than 20 years ago when Mr. K. H. Norris firstly introduced the near infrared spectroscopy (NIRS) as a powerful technology in the field of composition analysis of cereals those who were interested in the area of classical spectroscopy would not like to recognize its potential. This tendency still remains at present however it leaves no room for doubt that from viewpoints of applied spectroscopy the NIRS has consolidated its position. From a viewpoint of NIRS application in the field of nondestructive or non invasive measuring techniques history of this technology is only the last decade in Japan. However since the technology was firstly introduced to composition analysis of agricultural commodities in the same manner as in other countries R and D have been growing more actively in diversified fields such as agriculture and industry as well as medical science. In addition the NIRS technology are becoming of general interest by combining other techniques to create various hyphenated instrumentations such as FTNIR MCFTNIR NIRCT and NIR-NMR. In this paper new trends of R D on NIR spectroscopy which are being conducted in Japan will be reviewed. 2. S1JMMARY OF PRESENT R D ON NIRS IN JAPAN NIRS applications reported in the last 3 years are summarized in Table 1. Table 1 Applications of NIRS in Japan Application for Agriculture Taste evaluation of rice and coffee Determination of chemical compositions rice for breeding Determination of chemical compositions in tea Determination of sugar contents in intact peaches Japanese pears Satsuma oranges and apples Determination of sugars and acids in intact tomatoes Determination of forage composition Application for Industry Analysis of state of water in foods Application of analyzing Maillard Reaction''s Process Pattern recognition of NIR spectra as related to process control of roasting coffee beans Quality control of tea processing Determination of moisture content of Surimi products 2 / SPIE Vol. 1379 Optics in Agriculture

  10. Infrared spectroscopy of strained BaTiO.sub.3./sub./SrTiO.sub.3./sub. superlattices on scandate substrates

    Czech Academy of Sciences Publication Activity Database

    Železný, Vladimír; Soukiassian, A.; Xi, X.X.; Schlom, G.

    2014-01-01

    Roč. 87, 10-11 (2014), s. 929-937 ISSN 0141-1594 Institutional support: RVO:68378271 Keywords : infrared spectroscopy * ferroelectric superlattices * perovskites Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.954, year: 2014

  11. Infrared spectroscopy of copper-resveratrol complexes: A joint experimental and theoretical study

    Energy Technology Data Exchange (ETDEWEB)

    Chiavarino, B.; Crestoni, M. E.; Fornarini, S. [Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza - Universita di Roma, Piazzale A. Moro 5, 00185 Rome (Italy); Taioli, S. [Interdisciplinary Laboratory for Computational Science, FBK-CMM and University of Trento, Via Sommarive 18, 38123 Trento (Italy); Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Perugia (Italy); Department of Chemistry, University of Bologna, Via F. Selmi 2, I-40126 Bologna (Italy); Mancini, I.; Tosi, P. [Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento (Italy)

    2012-07-14

    Infrared multiple-photon dissociation spectroscopy has been used to record vibrational spectra of charged copper-resveratrol complexes in the 3500-3700 cm{sup -1} and 1100-1900 cm{sup -1} regions. Minimum energy structures have been determined by density functional theory calculations using plane waves and pseudopotentials. In particular, the copper(I)-resveratrol complex presents a tetra-coordinated metal bound with two carbon atoms of the alkenyl moiety and two closest carbons of the adjoining resorcinol ring. For these geometries vibrational spectra have been calculated by using linear response theory. The good agreement between experimental and calculated IR spectra for the selected species confirms the overall reliability of the proposed geometries.

  12. Broad-band time-resolved near infrared spectroscopy in the TJ-II stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, M.C.; Pastor, I.; Cal, E. de la; McCarthy, K.J. [Laboratorio Nacional de Fusion, CIEMAT, Madrid (Spain); Diaz, D. [Universidad Autonoma de Madrid, Dept Quimica Fisica Aplicada, Madrid (Spain)

    2014-11-15

    First experimental results on broad-band, time-resolved Near Infrared (NIR;here loosely defined as covering from 750 to 1650 nm) passive spectroscopy using a high sensitivity InGaAs detector are reported for the TJ-II Stellarator. Experimental set-up is described together with its main characteristics, the most remarkable ones being its enhanced NIR response, broadband spectrum acquisition in a single shot, and time-resolved measurements with up to 1.8 kHz spectral rate. Prospects for future work and more extended physics studies in this newly open spectral region in TJ-II are discussed. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Adsorption of 1- and 2-butylimidazoles at the copper/air and steel/air interfaces studied by sum frequency generation vibrational spectroscopy.

    Science.gov (United States)

    Casford, Michael T L; Davies, Paul B

    2012-07-24

    The structure of thin films of 1- and 2-butylimidazoles adsorbed on copper and steel surfaces under air was examined using sum frequency generation (SFG) vibrational spectroscopy in the ppp and ssp polarizations. Additionally, the SFG spectra of both isomers were recorded at 55 °C at the liquid imidazole/air interface for reference. Complementary bulk infrared, reflection-absorption infrared spectroscopy (RAIRS), and Raman spectra of both imidazoles were recorded for assignment purposes. The SFG spectra in the C-H stretching region at the liquid/air interface are dominated by resonances from the methyl end group of the butyl side chain of the imidazoles, indicating that they are aligned parallel or closely parallel to the surface normal. These are also the most prominent features in the SFG spectra on copper and steel. In addition, both the ppp and ssp spectra on copper show resonances from the C-H stretching modes of the imidazole ring for both isomers. The ring C-H resonances are completely absent from the spectra on steel and at the liquid/air interface. The relative intensities of the SFG spectra can be interpreted as showing that, on copper, under air, both butylimidazoles are adsorbed with their butyl side chains perpendicular to the interface and with the ring significantly inclined away from the surface plane and toward the surface normal. The SFG spectra of both imidazoles on steel indicate an orientation where the imidazole rings are parallel or nearly parallel to the surface. The weak C-H resonances from the ring at the liquid/air interface suggest that the tilt angle of the ring from the surface normal at this interface is significantly greater than it is on copper.

  14. A review: Functional near infrared spectroscopy evaluation in muscle tissues using Monte Carlo simulation

    Science.gov (United States)

    Halim, A. A. A.; Laili, M. H.; Salikin, M. S.; Rusop, M.

    2018-05-01

    Monte Carlo Simulation has advanced their quantification based on number of the photon counting to solve the propagation of light inside the tissues including the absorption, scattering coefficient and act as preliminary study for functional near infrared application. The goal of this paper is to identify the optical properties using Monte Carlo simulation for non-invasive functional near infrared spectroscopy (fNIRS) evaluation of penetration depth in human muscle. This paper will describe the NIRS principle and the basis for its proposed used in Monte Carlo simulation which focused on several important parameters include ATP, ADP and relate with blow flow and oxygen content at certain exercise intensity. This will cover the advantages and limitation of such application upon this simulation. This result may help us to prove that our human muscle is transparent to this near infrared region and could deliver a lot of information regarding to the oxygenation level in human muscle. Thus, this might be useful for non-invasive technique for detecting oxygen status in muscle from living people either athletes or working people and allowing a lots of investigation muscle physiology in future.

  15. Long open-path measurements of greenhouse gases in air using near-infrared Fourier transform spectroscopy

    Science.gov (United States)

    Griffith, David W. T.; Pöhler, Denis; Schmitt, Stefan; Hammer, Samuel; Vardag, Sanam N.; Platt, Ulrich

    2018-03-01

    In complex and urban environments, atmospheric trace gas composition is highly variable in time and space. Point measurement techniques for trace gases with in situ instruments are well established and accurate, but do not provide spatial averaging to compare against developing high-resolution atmospheric models of composition and meteorology with resolutions of the order of a kilometre. Open-path measurement techniques provide path average concentrations and spatial averaging which, if sufficiently accurate, may be better suited to assessment and interpretation with such models. Open-path Fourier transform spectroscopy (FTS) in the mid-infrared region, and differential optical absorption spectroscopy (DOAS) in the UV and visible, have been used for many years for open-path spectroscopic measurements of selected species in both clean air and in polluted environments. Near infrared instrumentation allows measurements over longer paths than mid-infrared FTS for species such as greenhouse gases which are not easily accessible to DOAS.In this pilot study we present the first open-path near-infrared (4000-10 000 cm-1, 1.0-2.5 µm) FTS measurements of CO2, CH4, O2, H2O and HDO over a 1.5 km path in urban Heidelberg, Germany. We describe the construction of the open-path FTS system, the analysis of the collected spectra, several measures of precision and accuracy of the measurements, and the results a four-month trial measurement period in July-November 2014. The open-path measurements are compared to calibrated in situ measurements made at one end of the open path. We observe significant differences of the order of a few ppm for CO2 and a few tens of ppb for CH4 between the open-path and point measurements which are 2 to 4 times the measurement repeatability, but we cannot unequivocally assign the differences to specific local sources or sinks. We conclude that open-path FTS may provide a valuable new tool for investigations of atmospheric trace gas composition in

  16. Variable selection in near-infrared spectroscopy: Benchmarking of feature selection methods on biodiesel data

    International Nuclear Information System (INIS)

    Balabin, Roman M.; Smirnov, Sergey V.

    2011-01-01

    During the past several years, near-infrared (near-IR/NIR) spectroscopy has increasingly been adopted as an analytical tool in various fields from petroleum to biomedical sectors. The NIR spectrum (above 4000 cm -1 ) of a sample is typically measured by modern instruments at a few hundred of wavelengths. Recently, considerable effort has been directed towards developing procedures to identify variables (wavelengths) that contribute useful information. Variable selection (VS) or feature selection, also called frequency selection or wavelength selection, is a critical step in data analysis for vibrational spectroscopy (infrared, Raman, or NIRS). In this paper, we compare the performance of 16 different feature selection methods for the prediction of properties of biodiesel fuel, including density, viscosity, methanol content, and water concentration. The feature selection algorithms tested include stepwise multiple linear regression (MLR-step), interval partial least squares regression (iPLS), backward iPLS (BiPLS), forward iPLS (FiPLS), moving window partial least squares regression (MWPLS), (modified) changeable size moving window partial least squares (CSMWPLS/MCSMWPLSR), searching combination moving window partial least squares (SCMWPLS), successive projections algorithm (SPA), uninformative variable elimination (UVE, including UVE-SPA), simulated annealing (SA), back-propagation artificial neural networks (BP-ANN), Kohonen artificial neural network (K-ANN), and genetic algorithms (GAs, including GA-iPLS). Two linear techniques for calibration model building, namely multiple linear regression (MLR) and partial least squares regression/projection to latent structures (PLS/PLSR), are used for the evaluation of biofuel properties. A comparison with a non-linear calibration model, artificial neural networks (ANN-MLP), is also provided. Discussion of gasoline, ethanol-gasoline (bioethanol), and diesel fuel data is presented. The results of other spectroscopic

  17. Second harmonic generation spectroscopy in the Reststrahl band of SiC using an infrared free-electron laser

    Energy Technology Data Exchange (ETDEWEB)

    Paarmann, Alexander, E-mail: alexander.paarmann@fhi-berlin.mpg.de; Razdolski, Ilya; Melnikov, Alexey; Gewinner, Sandy; Schöllkopf, Wieland; Wolf, Martin [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany)

    2015-08-24

    The Reststrahl spectral region of silicon carbide has recently attracted much attention owing to its potential for mid-infrared nanophotonic applications based on surface phonon polaritons (SPhPs). Studies of optical phonon resonances responsible for surface polariton formation, however, have so far been limited to linear optics. In this Letter, we report the first nonlinear optical investigation of the Reststrahl region of SiC, employing an infrared free-electron laser to perform second harmonic generation (SHG) spectroscopy. We observe two distinct resonance features in the SHG spectra, one attributed to resonant enhancement of the nonlinear susceptibility χ{sup (2)} and the other due to a resonance in the Fresnel transmission. Our work clearly demonstrates high sensitivity of mid-infrared SHG to phonon-driven phenomena and opens a route to studying nonlinear effects in nanophotonic structures based on SPhPs.

  18. Fourier transform infrared spectroscopy microscopic imaging classification based on spatial-spectral features

    Science.gov (United States)

    Liu, Lian; Yang, Xiukun; Zhong, Mingliang; Liu, Yao; Jing, Xiaojun; Yang, Qin

    2018-04-01

    The discrete fractional Brownian incremental random (DFBIR) field is used to describe the irregular, random, and highly complex shapes of natural objects such as coastlines and biological tissues, for which traditional Euclidean geometry cannot be used. In this paper, an anisotropic variable window (AVW) directional operator based on the DFBIR field model is proposed for extracting spatial characteristics of Fourier transform infrared spectroscopy (FTIR) microscopic imaging. Probabilistic principal component analysis first extracts spectral features, and then the spatial features of the proposed AVW directional operator are combined with the former to construct a spatial-spectral structure, which increases feature-related information and helps a support vector machine classifier to obtain more efficient distribution-related information. Compared to Haralick’s grey-level co-occurrence matrix, Gabor filters, and local binary patterns (e.g. uniform LBPs, rotation-invariant LBPs, uniform rotation-invariant LBPs), experiments on three FTIR spectroscopy microscopic imaging datasets show that the proposed AVW directional operator is more advantageous in terms of classification accuracy, particularly for low-dimensional spaces of spatial characteristics.

  19. Evaluation of chemical parameters in soft mold-ripened cheese during ripening by mid-infrared spectroscopy.

    Science.gov (United States)

    Martín-del-Campo, S T; Picque, D; Cosío-Ramírez, R; Corrieu, G

    2007-06-01

    The suitability of mid-infrared spectroscopy (MIR) to follow the evolution throughout ripening of specific physicochemical parameters in Camembert-type cheeses was evaluated. The infrared spectra were obtained directly from raw cheese samples deposited on an attenuated total reflectance crystal. Significant correlations were observed between physicochemical data, pH, acid-soluble nitrogen, nonprotein nitrogen, ammonia (NH4+), lactose, and lactic acid. Dry matter showed significant correlation only with lactose and nonprotein nitrogen. Principal components analysis factorial maps of physicochemical data showed a ripening evolution in 2 steps, from d 1 to d 7 and from d 8 to d 27, similar to that observed previously from infrared spectral data. Partial least squares regressions made it possible to obtain good prediction models for dry matter, acid-soluble nitrogen, nonprotein nitrogen, lactose, lactic acid, and NH4+ values from spectral data of raw cheese. The values of 3 statistical parameters (coefficient of determination, root mean square error of cross validation, and ratio prediction deviation) are satisfactory. Less precise models were obtained for pH.

  20. Rapid and simultaneous determination of lycopene and beta-carotene contents in tomato juice by infrared spectroscopy.

    Science.gov (United States)

    De Nardo, Thais; Shiroma-Kian, Cecilia; Halim, Yuwana; Francis, David; Rodriguez-Saona, Luis E

    2009-02-25

    The rapid quantification of lycopene and beta-carotene in tomato juices by attenuated total reflectance (ATR) infrared spectroscopy combined with multivariate analysis was evaluated. Two sample preparation methods were compared: a direct measurement of the tomato paste and an extraction method using hexane to isolate carotenoids. HPLC was used as the reference method. Cross-validated (leave-one-out) partial least-squares regression (PLSR) was used to create calibration models to predict these phytonutrient concentrations in blind test samples. The infrared spectra showed unique marker bands at 957 and 968 cm(-1) for lycopene and beta-carotene, respectively. Multivariate analysis of the infrared spectral data gave correlation coefficients (r values) of >0.9 between the ATR-IR predicted and HPLC reference values, and standard errors of cross-validation (SECV) of 0.5 and 0.04 mg/100 g of juice for lycopene and beta-carotene, respectively. ATR-IR could provide the tomato industry with a simple, rapid, and high-throughput technique for the determination of tomato quality.

  1. High Resolution Infrared Spectroscopy in Astronomy Proceedings of an ESO Workshop Held at Garching, Germany, 18-21 November 2003

    CERN Document Server

    Käufl, Hans Ulrich; Moorwood, Alan F. M

    2005-01-01

    Two specialized new instruments for ESO's VLT, VISIR and CRIRES, spawned the idea for this workshop. CRIRES is a dedicated very high resolution infrared spectrograph; VISIR features a high resolution spectroscopic mode. Together, the instruments combine the sensitivity of an 8m-telescope with the now well-established reliability of VLT-facility instruments. High resolution here means that lines in cool stellar atmospheres and HII-regions can be resolved. The astrophysical topics discussed in this rather specialized workshop range from the inner solar system to active galactic nuclei. There are many possibilities for new discoveries with these instruments, but the unique capability, which becomes available through high-resolution infrared spectroscopy, is the observation of molecular rotational-vibrational transitions in many astrophysical environments. Particularly interesting and surprising in this context, many papers on modeling and laboratory spectroscopy at the workshop appear to indicate that astronomic...

  2. Surface chemistry of plasma-assisted atomic layer deposition of Al2O3 studied by infrared spectroscopy

    NARCIS (Netherlands)

    Langereis, E.; Keijmel, J.; Sanden, van de M.C.M.; Kessels, W.M.M.

    2008-01-01

    The surface groups created during plasma-assisted atomic layer deposition (ALD) of Al2O3 were studied by infrared spectroscopy. For temperatures in the range of 25–150 °C, –CH3 and –OH were unveiled as dominant surface groups after the Al(CH3)3precursor and O2 plasma half-cycles, respectively. At

  3. 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.)

  4. 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.

  5. Application of far-infrared spectroscopy to the structural identification of protein materials.

    Science.gov (United States)

    Han, Yanchen; Ling, Shengjie; Qi, Zeming; Shao, Zhengzhong; Chen, Xin

    2018-05-03

    Although far-infrared (IR) spectroscopy has been shown to be a powerful tool to determine peptide structure and to detect structural transitions in peptides, it has been overlooked in the characterization of proteins. Herein, we used far-IR spectroscopy to monitor the structure of four abundant non-bioactive proteins, namely, soybean protein isolate (SPI), pea protein isolate (PPI) and two types of silk fibroins (SFs), domestic Bombyx mori and wild Antheraea pernyi. The two globular proteins SPI and PPI result in broad and weak far-IR bands (between 50 and 700 cm-1), in agreement with those of some other bioactive globular proteins previously studied (lysozyme, myoglobin, hemoglobin, etc.) that generally only have random amino acid sequences. Interestingly, the two SFs, which are characterized by a structure composed of highly repetitive motifs, show several sharp far-IR characteristic absorption peaks. Moreover, some of these characteristic peaks (such as the peaks at 260 and 428 cm-1 in B. mori, and the peaks at 245 and 448 cm-1 in A. pernyi) are sensitive to conformational changes; hence, they can be directly used to monitor conformational transitions in SFs. Furthermore, since SF absorption bands clearly differ from those of globular proteins and different SFs even show distinct adsorption bands, far-IR spectroscopy can be applied to distinguish and determine the specific SF component within protein blends.

  6. 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

  7. Nucleic acid interactions with pyrite surfaces

    International Nuclear Information System (INIS)

    Mateo-Marti, E.; Briones, C.; Rogero, C.; Gomez-Navarro, C.; Methivier, Ch.; Pradier, C.M.; Martin-Gago, J.A.

    2008-01-01

    The study of the interaction of nucleic acid molecules with mineral surfaces is a field of growing interest in organic chemistry, origin of life, material science and biotechnology. We have characterized the adsorption of single-stranded peptide nucleic acid (ssPNA) on a natural pyrite surface, as well as the further adsorption of ssDNA on a PNA-modified pyrite surface. The characterization has been performed by means of reflection absorption infrared spectroscopy (RAIRS), atomic force microscopy (AFM) and X-ray photoemission spectroscopy (XPS) techniques. The N(1s) and S(2p) XPS core level peaks of PNA and PNA + DNA have been decomposed in curve-components that we have assigned to different chemical species. RAIRS spectra recorded for different concentrations show the presence of positive and negative adsorption bands, related to the semiconducting nature of the surface. The combination of the information gathered by these techniques confirms that PNA adsorbs on pyrite surface, interacting through nitrogen-containing groups of the nucleobases and the iron atoms of the surface, instead of the thiol group of the molecule. The strong PNA/pyrite interaction inhibits further hybridization of PNA with complementary ssDNA, contrary to the behavior reported on gold surfaces

  8. Nucleic acid interactions with pyrite surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Mateo-Marti, E. [Centro de Astrobiologia (CSIC-INTA), Ctra. Ajalvir, Km. 4, 28850-Torrejon de Ardoz, Madrid (Spain)], E-mail: mateome@inta.es; Briones, C.; Rogero, C. [Centro de Astrobiologia (CSIC-INTA), Ctra. Ajalvir, Km. 4, 28850-Torrejon de Ardoz, Madrid (Spain); Gomez-Navarro, C. [Instituto de Ciencia de Materiales de Madrid (CSIC), Cantoblanco, 28049-Madrid (Spain); Methivier, Ch.; Pradier, C.M. [Laboratoire de Reactivite de Surface, UMR CNRS 7609. Universite Pierre et Marie Curie, 4, Pl Jussieu, 75005-Paris (France); Martin-Gago, J.A. [Centro de Astrobiologia (CSIC-INTA), Ctra. Ajalvir, Km. 4, 28850-Torrejon de Ardoz, Madrid (Spain); Instituto de Ciencia de Materiales de Madrid (CSIC), Cantoblanco, 28049-Madrid (Spain)

    2008-09-03

    The study of the interaction of nucleic acid molecules with mineral surfaces is a field of growing interest in organic chemistry, origin of life, material science and biotechnology. We have characterized the adsorption of single-stranded peptide nucleic acid (ssPNA) on a natural pyrite surface, as well as the further adsorption of ssDNA on a PNA-modified pyrite surface. The characterization has been performed by means of reflection absorption infrared spectroscopy (RAIRS), atomic force microscopy (AFM) and X-ray photoemission spectroscopy (XPS) techniques. The N(1s) and S(2p) XPS core level peaks of PNA and PNA + DNA have been decomposed in curve-components that we have assigned to different chemical species. RAIRS spectra recorded for different concentrations show the presence of positive and negative adsorption bands, related to the semiconducting nature of the surface. The combination of the information gathered by these techniques confirms that PNA adsorbs on pyrite surface, interacting through nitrogen-containing groups of the nucleobases and the iron atoms of the surface, instead of the thiol group of the molecule. The strong PNA/pyrite interaction inhibits further hybridization of PNA with complementary ssDNA, contrary to the behavior reported on gold surfaces.

  9. 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.

  10. Alternative method to trace sediment sources in a subtropical rural catchment of southern Brazil by using near-infrared spectroscopy

    Science.gov (United States)

    Tiecher, Tales; Caner, Laurent; Gomes Minella, Jean Paolo; Henrique Ciotti, Lucas; Antônio Bender, Marcos; dos Santos Rheinheimer, Danilo

    2014-05-01

    Conventional fingerprinting methods based on geochemical composition still require a time-consuming and critical preliminary sample preparation. Thus, fingerprinting characteristics that can be measured in a rapid and cheap way requiring a minimal sample preparation, such as spectroscopy methods, should be used. The present study aimed to evaluate the sediment sources contribution in a rural catchment by using conventional method based on geochemical composition and on an alternative method based on near-infrared spectroscopy. This study was carried out in a rural catchment with an area of 1,19 km2 located in southern Brazil. The sediment sources evaluated were crop fields (n=20), unpaved roads (n=10) and stream channels (n=10). Thirty suspended sediment samples were collected from eight significant storm runoff events between 2009 and 2011. Sources and sediment samples were dried at 50oC and sieved at 63 µm. The total concentration of Ag, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sr, Ti, Tl, V and Zn were estimated by ICP-OES after microwave assisted digestion with concentrated HNO3 and HCl. Total organic carbon (TOC) was estimated by wet oxidation with K2Cr2O7 and H2SO4. The near-infrared spectra scan range was 4000 to 10000 cm-1 at a resolution of 2 cm-1, with 100 co added scans per spectrum. The steps used in the conventional method were: i) tracer selection based on Kruskal-Wallis test, ii) selection of the best set of tracers using discriminant analyses and finally iii) the use of a mixed linear model to calculate the sediment sources contribution. The steps used in the alternative method were i) principal component analyses to reduce the number of variables, ii) discriminant analyses to determine the tracer potential of the near-infrared spectroscopy, and finally iii) the use of past least square based on 48 mixtures of the sediment sources in various weight proportions to calculate the sediment sources

  11. Spectroscopy

    CERN Document Server

    Walker, S

    1976-01-01

    The three volumes of Spectroscopy constitute the one comprehensive text available on the principles, practice and applications of spectroscopy. By giving full accounts of those spectroscopic techniques only recently introduced into student courses - such as Mössbauer spectroscopy and photoelectron spectroscopy - in addition to those techniques long recognised as being essential in chemistry teaching - sucha as e.s.r. and infrared spectroscopy - the book caters for the complete requirements of undergraduate students and at the same time provides a sound introduction to special topics for graduate students.

  12. Nanoantennas for surface enhanced infrared spectroscopy: Effects of interaction and higher order resonant excitations

    Directory of Open Access Journals (Sweden)

    J. Aizpurua

    2011-09-01

    Full Text Available The sensitivity in surface enhanced infrared spectroscopy (SEIRS strongly depends on where the resonant excitation is spectrally located compared to the molecular vibration that is to be enhanced. In this contribution, we study the effect of coupling in the electromagnetic properties of 2D gold nanorod arrays in the IR. We also study the SEIRS activity of higher order resonant excitations in long nanoantennas to identify polaritonic signals of a supporting SiO2 layer with nanometer thickness (3 nm on a silicon substrate.

  13. Study of atmospheric air AC glow discharge using optical emission spectroscopy and near infrared diode laser cavity ringdown spectroscopy

    Science.gov (United States)

    Srivastava, Nimisha; Wang, Chuji; Dibble, Theodore S.

    2008-11-01

    AC glow discharges were generated in atmospheric pressure by applying high voltage AC in the range of 3500-15000 V to a pair of stainless steel electrodes separated by an air gap. The discharges were characterized by optical emission spectroscopy (OES) and continuous wave cavity ringdown spectroscopy (cw-CRDS). The electronic (Tex), vibrational (Tv), and rotational (Tr) temperatures were measured. Spectral stimulations of the emission spectra of several vibronic bands of the 2^nd positive system of N2, the 1^st negative system of N2^+, the (0,1,2,3-0) bands of NO (A-X), and the (0-0) band of OH (A-X), which were obtained under various plasma operating conditions, show that Tr, Tv, and Tex are in the ranges of 2000 - 3800, 3500 - 5000, and 6000 - 10500^ K, respectively. Emission spectra show that OH concentration increases while NO concentration decreases with an increase of electrode spacing. The absorption spectra of H2O and OH overtone in the near infrared (NIR) were measured by the cw-CRDS with a telecommunications diode laser at wavelength near 1515 nm.

  14. Hyphenation of infrared spectroscopy to liquid chromatography for qualitative and quantitative polymer analysis: Degradation of poly(bisphenol A)carbonate

    NARCIS (Netherlands)

    Coulier, L.; Kaal, E.; Hankemeier, T.

    2006-01-01

    Hyphenation of infrared spectroscopy (IR) to liquid chromatography (LC) has been applied to study chemical changes in poly(bisphenol A)carbonate (PC) as a result of degradation. Especially coupling of LC to FTIR through solvent elimination is a sensitive approach to identify changes in functionality

  15. Photoleucine Survives Backbone Cleavage by Electron Transfer Dissociation. A Near-UV Photodissociation and Infrared Multiphoton Dissociation Action Spectroscopy Study

    Czech Academy of Sciences Publication Activity Database

    Shaffer, C. J.; Martens, J.; Marek, Aleš; Oomens, J.; Tureček, F.

    2016-01-01

    Roč. 27, č. 7 (2016), s. 1176-1185 ISSN 1044-0305 Institutional support: RVO:61388963 Keywords : peptide ions * electron transfer dissociation * photoleucine label * near-UV photodissociation * infrared multiphoton dissociation action spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.786, year: 2016

  16. 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

  17. 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...

  18. Vibrational spectroscopy

    Science.gov (United States)

    Umesh P. Agarwal; Rajai Atalla

    2010-01-01

    Vibrational spectroscopy is an important tool in modern chemistry. In the past two decades, thanks to significant improvements in instrumentation and the development of new interpretive tools, it has become increasingly important for studies of lignin. This chapter presents the three important instrumental methods-Raman spectroscopy, infrared (IR) spectroscopy, and...

  19. Structure of cesium loaded iron phosphate glasses: An infrared and Raman spectroscopy study

    International Nuclear Information System (INIS)

    Joseph, Kitheri; Premila, M.; Amarendra, G.; Govindan Kutty, K.V.; Sundar, C.S.; Vasudeva Rao, P.R.

    2012-01-01

    The structure of cesium loaded iron phosphate glasses (IPG) was investigated using infrared and Raman spectroscopy. The spectra of the cesium doped samples revealed a structural modification of the parent glass owing to the incorporation of cesium. The structural changes could be correlated with the variation observed in the glass transition temperature of these glasses. Increased Cs-mediated cationic cross linking appears to be the reason for the initial rise in glass transition temperature up to 21 mol% Cs 2 O in IPG; while, breakdown of the phosphate network with increasing cesium content, brings down the glass transition temperature.

  20. Raman, Infrared, and Laser-Induced Breakdown Spectroscopy Identification of Particles in Raw Materials.

    Science.gov (United States)

    Lee, Kathryn; Lankers, Markus; Valet, Oliver

    2018-02-01

    Raw materials need to be of a certain quality with respect to physical and chemical composition. They also need to have no contaminants, including particles, because these could indicate raw material impurities or contaminate the product. Particle identification allows determination of process conditions that caused them and whether the quality of the final product is acceptable. Particles may appear to the eye to be very different things than they actually are. They may be coated with the raw material and may consist of several components; therefore, chemical and elemental analyses are required for accuracy in proper identification and definitive information about their source. Thus, microscope versions of Raman spectroscopy, laser-induced breakdown spectroscopy (LIBS), and infrared (IR) spectroscopy are excellent tools for identifying particles in materials. Those tools are fast and accurate, and can provide chemical and elemental composition as well as images that can aid identification. The micro-analysis capabilities allow for easy analysis of different portions of samples so that multiple components can be identified and sample preparation can be reduced or eliminated. The differences in sensitivities of Raman and IR spectroscopies to different functional groups as well as the elemental analysis provided by LIBS and the image analysis provided by the microscopy makes these complementary techniques and provides the advantage of identifying various chemical components. Proper spectral searching techniques and interpretation of the results are important for interpretation and identification of trace contaminants.

  1. 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.

  2. Sensitivity of near-infrared spectroscopy and diffuse correlation spectroscopy to brain hemodynamics: simulations and experimental findings during hypercapnia.

    Science.gov (United States)

    Selb, Juliette; Boas, David A; Chan, Suk-Tak; Evans, Karleyton C; Buckley, Erin M; Carp, Stefan A

    2014-07-01

    Near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) are two diffuse optical technologies for brain imaging that are sensitive to changes in hemoglobin concentrations and blood flow, respectively. Measurements for both modalities are acquired on the scalp, and therefore hemodynamic processes in the extracerebral vasculature confound the interpretation of cortical hemodynamic signals. The sensitivity of NIRS to the brain versus the extracerebral tissue and the contrast-to-noise ratio (CNR) of NIRS to cerebral hemodynamic responses have been well characterized, but the same has not been evaluated for DCS. This is important to assess in order to understand their relative capabilities in measuring cerebral physiological changes. We present Monte Carlo simulations on a head model that demonstrate that the relative brain-to-scalp sensitivity is about three times higher for DCS (0.3 at 3 cm) than for NIRS (0.1 at 3 cm). However, because DCS has higher levels of noise due to photon-counting detection, the CNR is similar for both modalities in response to a physiologically realistic simulation of brain activation. Even so, we also observed higher CNR of the hemodynamic response during graded hypercapnia in adult subjects with DCS than with NIRS.

  3. Correlation between near infrared spectroscopy and electrical techniques in measuring skin moisture content

    International Nuclear Information System (INIS)

    Mohamad, M; Sabbri, A R M; Jafri, M Z Mat; Omar, A F

    2014-01-01

    Near infrared (NIR) spectroscopy technique serves as an important tool for the measurement of moisture content of skin owing to the advantages it has over the other techniques. The purpose of the study is to develop a correlation between NIR spectrometer with electrical conventional techniques for skin moisture measurement. A non-invasive measurement of moisture content of skin was performed on different part of human face and hand under control environment (temperature 21 ± 1 °C, relative humidity 45 ± 5 %). Ten healthy volunteers age between 21-25 (male and female) participated in this study. The moisture content of skin was measured using DermaLab ® USB Moisture Module, Scalar Moisture Checker and NIR spectroscopy (NIRQuest). Higher correlation was observed between NIRQuest and Dermalab moisture probe with a coefficient of determination (R 2 ) above 70 % for all the subjects. However, the value of R 2 between NIRQuest and Moisture Checker was observed to be lower with the R 2 values ranges from 51.6 to 94.4 %. The correlation of NIR spectroscopy technique successfully developed for measuring moisture content of the skin. The analysis of this correlation can help to establish novel instruments based on an optical system in clinical used especially in the dermatology field

  4. The use of near-infrared spectroscopy in understanding skeletal muscle physiology: recent developments.

    Science.gov (United States)

    Ferrari, Marco; Muthalib, Makii; Quaresima, Valentina

    2011-11-28

    This article provides a snapshot of muscle near-infrared spectroscopy (NIRS) at the end of 2010 summarizing the recent literature, offering the present status and perspectives of the NIRS instrumentation and methods, describing the main NIRS studies on skeletal muscle physiology, posing open questions and outlining future directions. So far, different NIRS techniques (e.g. continuous-wave (CW) and spatially, time- and frequency-resolved spectroscopy) have been used for measuring muscle oxygenation during exercise. In the last four years, approximately 160 muscle NIRS articles have been published on different physiological aspects (primarily muscle oxygenation and haemodynamics) of several upper- and lower-limb muscle groups investigated by using mainly two-channel CW and spatially resolved spectroscopy commercial instruments. Unfortunately, in only 15 of these studies were the advantages of using multi-channel instruments exploited. There are still several open questions in the application of NIRS in muscle studies: (i) whether NIRS can be used in subjects with a large fat layer; (ii) the contribution of myoglobin desaturation to the NIRS signal during exercise; (iii) the effect of scattering changes during exercise; and (iv) the effect of changes in skin perfusion, particularly during prolonged exercise. Recommendations for instrumentation advancements and future muscle NIRS studies are provided.

  5. 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.

  6. Cerebral oxygenation as measured by near-infrared spectroscopy in neonatal intensive care: correlation with arterial oxygenation.

    Science.gov (United States)

    Hunter, Carol Lu; Oei, Ju Lee; Lui, Kei; Schindler, Timothy

    2017-07-01

    To assess correlation between cerebral oxygenation (rScO 2 ), as measured by near-infrared spectroscopy (NIRS), and arterial oxygenation (PaO 2 ), as measured by arterial blood gases, in preterm neonates. Preterm neonates interpretation of NIRS values in neonatal intensive care, and further evaluation is needed to determine the applicability of NIRS to management of preterm infants. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  7. 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

  8. 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

  9. 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

  10. 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.

  11. Infrared spectroscopy of copper-resveratrol complexes: A joint experimental and theoretical study

    International Nuclear Information System (INIS)

    Chiavarino, B.; Crestoni, M. E.; Fornarini, S.; Taioli, S.; Mancini, I.; Tosi, P.

    2012-01-01

    Infrared multiple-photon dissociation spectroscopy has been used to record vibrational spectra of charged copper-resveratrol complexes in the 3500–3700 cm −1 and 1100–1900 cm −1 regions. Minimum energy structures have been determined by density functional theory calculations using plane waves and pseudopotentials. In particular, the copper(I)-resveratrol complex presents a tetra-coordinated metal bound with two carbon atoms of the alkenyl moiety and two closest carbons of the adjoining resorcinol ring. For these geometries vibrational spectra have been calculated by using linear response theory. The good agreement between experimental and calculated IR spectra for the selected species confirms the overall reliability of the proposed geometries.

  12. Application of the near-infrared spectroscopy in the pharmaceutical technology.

    Science.gov (United States)

    Jamrógiewicz, Marzena

    2012-07-01

    Near-infrared (NIR) spectroscopy is currently the fastest-growing and the most versatile analytical method not only in the pharmaceutical sciences but also in the industry. This review focuses on recent NIR applications in the pharmaceutical technology. This article covers monitoring, by NIR, of many manufacturing processes, such as granulation, mixing or drying, in order to determine the end-point of these processes. In this paper, apart from basic theoretical information concerning the NIR spectra, there are included determinations of the quality and quantity of pharmaceutical compounds. Some examples of measurements and control of physicochemical parameters of the final medicinal products, such as hardness, porosity, thickness size, compression strength, disintegration time and potential counterfeit are included. Biotechnology and plant drug analysis using NIR is also described. Moreover, some disadvantages of this method are stressed and future perspectives are anticipated. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Quantitative near-infrared spectroscopy on patients with peripheral vascular disease

    Science.gov (United States)

    Franceschini, Maria-Angela; Fantini, Sergio; Palumbo, Renato; Pasqualini, Leonella; Vaudo, Gaetano; Franceschini, Edoardo; Gratton, Enrico; Palumbo, Barbara; Innocente, Salvatore; Mannarino, Elmo

    1998-01-01

    We have used near-infrared spectroscopy to measure the hemoglobin saturation at rest and during exercise on patients affected by peripheral vascular disease (PVD). The instrument used in our study is a frequency-domain tissue oximeter which employs intensity modulated (110 MHz) laser diodes. We examined 9 subjects, 3 of which were controls and 6 were patients affected by stage II PVD. The optical probe was located on the calf muscle of the subjects. The measurement protocol consisted of: (1) baseline (approximately 5 min); (2) stationary bicycle exercise (approximately 5 min); (3) recovery (approximately 15 min). The change in hemoglobin saturation during exercise ((Delta) Y) and the recovery time after exercise (trec) were significantly greater in the PVD patients ((Delta) Y equals -21 +/- 3%, trec equals 5.9 +/- 3.8 min) than in the control subjects ((Delta) Y equals 2 +/- 3%, trec equals 0.6 +/- 0.1 min).

  14. 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.

  15. Adding a dimension to the infrared spectra of interfaces using heterodyne detected 2D sum-frequency generation (HD 2D SFG) spectroscopy.

    Science.gov (United States)

    Xiong, Wei; Laaser, Jennifer E; Mehlenbacher, Randy D; Zanni, Martin T

    2011-12-27

    In the last ten years, two-dimensional infrared spectroscopy has become an important technique for studying molecular structures and dynamics. We report the implementation of heterodyne detected two-dimensional sum-frequency generation (HD 2D SFG) spectroscopy, which is the analog of 2D infrared (2D IR) spectroscopy, but is selective to noncentrosymmetric systems such as interfaces. We implement the technique using mid-IR pulse shaping, which enables rapid scanning, phase cycling, and automatic phasing. Absorptive spectra are obtained, that have the highest frequency resolution possible, from which we extract the rephasing and nonrephasing signals that are sometimes preferred. Using this technique, we measure the vibrational mode of CO adsorbed on a polycrystalline Pt surface. The 2D spectrum reveals a significant inhomogenous contribution to the spectral line shape, which is quantified by simulations. This observation indicates that the surface conformation and environment of CO molecules is more complicated than the simple "atop" configuration assumed in previous work. Our method can be straightforwardly incorporated into many existing SFG spectrometers. The technique enables one to quantify inhomogeneity, vibrational couplings, spectral diffusion, chemical exchange, and many other properties analogous to 2D IR spectroscopy, but specifically for interfaces.

  16. Fourier transform infrared and fluorescence spectroscopy for analysis of vegetable oils

    Directory of Open Access Journals (Sweden)

    Nigri S.

    2013-09-01

    Full Text Available Fourier transform infrared (FTIR and fluorescence spectroscopy, combined with chemometric approaches have been developed to analysis of extra virgin olive oil adulterated with pomace olive oil. The measurements were made on pure vegetable oils: extra virgin oil, pomace olive oil and that adulterated with varying concentration of pomace olive oil. Today, the application of FTIR spectroscopy has increased in food studied, and particularly has become a powerful analytical tool in the study of edible oils and fats. The spectral regions where the variations were observed chosen for developing models and cross validation was used. The synchronous fluorescence spectrometry takes advantage of the hardware capability to vary both the excitation and emission wavelengths during the analysis with constant wavelength difference is maintained between the two. The region between 300 and 400 nm is attributed to the tocopherols and phenols, the derivatives of vitamin E are associated with the region 400–600 nm and the bands in the region of 600–700 nm are attributed to the chlorophyll and peophytin pigments. The results presented in this study suggest that FTIR and fluorescence may be a useful tool for analysis and detecting adulteration of extra virgin olive oil with pomace oil.

  17. Variety identification of brown sugar using short-wave near infrared spectroscopy and multivariate calibration

    Science.gov (United States)

    Yang, Haiqing; Wu, Di; He, Yong

    2007-11-01

    Near-infrared spectroscopy (NIRS) with the characteristics of high speed, non-destructiveness, high precision and reliable detection data, etc. is a pollution-free, rapid, quantitative and qualitative analysis method. A new approach for variety discrimination of brown sugars using short-wave NIR spectroscopy (800-1050nm) was developed in this work. The relationship between the absorbance spectra and brown sugar varieties was established. The spectral data were compressed by the principal component analysis (PCA). The resulting features can be visualized in principal component (PC) space, which can lead to discovery of structures correlative with the different class of spectral samples. It appears to provide a reasonable variety clustering of brown sugars. The 2-D PCs plot obtained using the first two PCs can be used for the pattern recognition. Least-squares support vector machines (LS-SVM) was applied to solve the multivariate calibration problems in a relatively fast way. The work has shown that short-wave NIR spectroscopy technique is available for the brand identification of brown sugar, and LS-SVM has the better identification ability than PLS when the calibration set is small.

  18. Rapid prediction of particulate, humus and resistant fractions of soil organic carbon in reforested lands using infrared spectroscopy.

    Science.gov (United States)

    Madhavan, Dinesh B; Baldock, Jeff A; Read, Zoe J; Murphy, Simon C; Cunningham, Shaun C; Perring, Michael P; Herrmann, Tim; Lewis, Tom; Cavagnaro, Timothy R; England, Jacqueline R; Paul, Keryn I; Weston, Christopher J; Baker, Thomas G

    2017-05-15

    Reforestation of agricultural lands with mixed-species environmental plantings can effectively sequester C. While accurate and efficient methods for predicting soil organic C content and composition have recently been developed for soils under agricultural land uses, such methods under forested land uses are currently lacking. This study aimed to develop a method using infrared spectroscopy for accurately predicting total organic C (TOC) and its fractions (particulate, POC; humus, HOC; and resistant, ROC organic C) in soils under environmental plantings. Soils were collected from 117 paired agricultural-reforestation sites across Australia. TOC fractions were determined in a subset of 38 reforested soils using physical fractionation by automated wet-sieving and 13 C nuclear magnetic resonance (NMR) spectroscopy. Mid- and near-infrared spectra (MNIRS, 6000-450 cm -1 ) were acquired from finely-ground soils from environmental plantings and agricultural land. Satisfactory prediction models based on MNIRS and partial least squares regression (PLSR) were developed for TOC and its fractions. Leave-one-out cross-validations of MNIRS-PLSR models indicated accurate predictions (R 2  > 0.90, negligible bias, ratio of performance to deviation > 3) and fraction-specific functional group contributions to beta coefficients in the models. TOC and its fractions were predicted using the cross-validated models and soil spectra for 3109 reforested and agricultural soils. The reliability of predictions determined using k-nearest neighbour score distance indicated that >80% of predictions were within the satisfactory inlier limit. The study demonstrated the utility of infrared spectroscopy (MNIRS-PLSR) to rapidly and economically determine TOC and its fractions and thereby accurately describe the effects of land use change such as reforestation on agricultural soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. HUBBLE SPACE TELESCOPE SPECTROSCOPY OF BROWN DWARFS DISCOVERED WITH THE WIDE-FIELD INFRARED SURVEY EXPLORER

    International Nuclear Information System (INIS)

    Schneider, Adam C.; Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R.; Mace, Gregory N.; Wright, Edward L.; Eisenhardt, Peter R.; Skrutskie, M. F.; Griffith, Roger L.; Marsh, Kenneth A.

    2015-01-01

    We present a sample of brown dwarfs identified with the Wide-field Infrared Survey Explorer (WISE) for which we have obtained Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) near-infrared grism spectroscopy. The sample (22 in total) was observed with the G141 grism covering 1.10–1.70 μm, while 15 were also observed with the G102 grism, which covers 0.90–1.10 μm. The additional wavelength coverage provided by the G102 grism allows us to (1) search for spectroscopic features predicted to emerge at low effective temperatures (e.g.,ammonia bands) and (2) construct a smooth spectral sequence across the T/Y boundary. We find no evidence of absorption due to ammonia in the G102 spectra. Six of these brown dwarfs are new discoveries, three of which are found to have spectral types of T8 or T9. The remaining three, WISE J082507.35+280548.5 (Y0.5), WISE J120604.38+840110.6 (Y0), and WISE J235402.77+024015.0 (Y1), are the 19th, 20th, and 21st spectroscopically confirmed Y dwarfs to date. We also present HST grism spectroscopy and reevaluate the spectral types of five brown dwarfs for which spectral types have been determined previously using other instruments

  20. HUBBLE SPACE TELESCOPE SPECTROSCOPY OF BROWN DWARFS DISCOVERED WITH THE WIDE-FIELD INFRARED SURVEY EXPLORER

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Adam C.; Cushing, Michael C. [Department of Physics and Astronomy, University of Toledo, 2801 W. Bancroft St., Toledo, OH 43606 (United States); Kirkpatrick, J. Davy; Gelino, Christopher R. [Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States); Mace, Gregory N.; Wright, Edward L. [Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States); Eisenhardt, Peter R. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109 (United States); Skrutskie, M. F. [Department of Astronomy, University of Virginia, 530 McCormick Road, Charlottesville, VA 22904 (United States); Griffith, Roger L. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Marsh, Kenneth A., E-mail: Adam.Schneider@Utoledo.edu [School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom)

    2015-05-10

    We present a sample of brown dwarfs identified with the Wide-field Infrared Survey Explorer (WISE) for which we have obtained Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) near-infrared grism spectroscopy. The sample (22 in total) was observed with the G141 grism covering 1.10–1.70 μm, while 15 were also observed with the G102 grism, which covers 0.90–1.10 μm. The additional wavelength coverage provided by the G102 grism allows us to (1) search for spectroscopic features predicted to emerge at low effective temperatures (e.g.,ammonia bands) and (2) construct a smooth spectral sequence across the T/Y boundary. We find no evidence of absorption due to ammonia in the G102 spectra. Six of these brown dwarfs are new discoveries, three of which are found to have spectral types of T8 or T9. The remaining three, WISE J082507.35+280548.5 (Y0.5), WISE J120604.38+840110.6 (Y0), and WISE J235402.77+024015.0 (Y1), are the 19th, 20th, and 21st spectroscopically confirmed Y dwarfs to date. We also present HST grism spectroscopy and reevaluate the spectral types of five brown dwarfs for which spectral types have been determined previously using other instruments.

  1. 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.

  2. Detection of compatibility between baclofen and excipients with aid of infrared spectroscopy and chemometry.

    Science.gov (United States)

    Rojek, Barbara; Wesolowski, Marek; Suchacz, Bogdan

    2013-12-01

    In the paper infrared (IR) spectroscopy and multivariate exploration techniques: principal component analysis (PCA) and cluster analysis (CA) were applied as supportive methods for the detection of physicochemical incompatibilities between baclofen and excipients. In the course of research, the most useful rotational strategy in PCA proved to be varimax normalized, while in CA Ward's hierarchical agglomeration with Euclidean distance measure enabled to yield the most interpretable results. Chemometrical calculations confirmed the suitability of PCA and CA as the auxiliary methods for interpretation of infrared spectra in order to recognize whether compatibilities or incompatibilities between active substance and excipients occur. On the basis of IR spectra and the results of PCA and CA it was possible to demonstrate that the presence of lactose, β-cyclodextrin and meglumine in binary mixtures produce interactions with baclofen. The results were verified using differential scanning calorimetry, differential thermal analysis, thermogravimetry/differential thermogravimetry and X-ray powder diffraction analyses. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. 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.

  4. Multi-parameters monitoring during traditional Chinese medicine concentration process with near infrared spectroscopy and chemometrics

    Science.gov (United States)

    Liu, Ronghua; Sun, Qiaofeng; Hu, Tian; Li, Lian; Nie, Lei; Wang, Jiayue; Zhou, Wanhui; Zang, Hengchang

    2018-03-01

    As a powerful process analytical technology (PAT) tool, near infrared (NIR) spectroscopy has been widely used in real-time monitoring. In this study, NIR spectroscopy was applied to monitor multi-parameters of traditional Chinese medicine (TCM) Shenzhiling oral liquid during the concentration process to guarantee the quality of products. Five lab scale batches were employed to construct quantitative models to determine five chemical ingredients and physical change (samples density) during concentration process. The paeoniflorin, albiflorin, liquiritin and samples density were modeled by partial least square regression (PLSR), while the content of the glycyrrhizic acid and cinnamic acid were modeled by support vector machine regression (SVMR). Standard normal variate (SNV) and/or Savitzkye-Golay (SG) smoothing with derivative methods were adopted for spectra pretreatment. Variable selection methods including correlation coefficient (CC), competitive adaptive reweighted sampling (CARS) and interval partial least squares regression (iPLS) were performed for optimizing the models. The results indicated that NIR spectroscopy was an effective tool to successfully monitoring the concentration process of Shenzhiling oral liquid.

  5. Has the time come to use near-infrared spectroscopy as a routine clinical tool in preterm infants undergoing intensive care?

    DEFF Research Database (Denmark)

    Greisen, Gorm; Leung, Terence; Wolf, Martin

    2011-01-01

    Several instruments implementing spatially resolved near-infrared spectroscopy (NIRS) to monitor tissue oxygenation are now approved for clinical use. The neonatal brain is readily assessible by NIRS and neurodevelopmental impairment is common in children who were in need of intensive care during...

  6. Near infrared spectroscopy is suitable for the classification of hazelnuts according to Protected Designation of Origin.

    Science.gov (United States)

    Moscetti, Roberto; Radicetti, Emanuele; Monarca, Danilo; Cecchini, Massimo; Massantini, Riccardo

    2015-10-01

    This study investigates the possibility of using near infrared spectroscopy for the authentication of the 'Nocciola Romana' hazelnut (Corylus avellana L. cvs Tonda Gentile Romana and Nocchione) as a Protected Designation of Origin (PDO) hazelnut from central Italy. Algorithms for the selection of the optimal pretreatments were tested in combination with the following discriminant routines: k-nearest neighbour, soft independent modelling of class analogy, partial least squares discriminant analysis and support vector machine discriminant analysis. The best results were obtained using a support vector machine discriminant analysis routine. Thus, classification performance rates with specificities, sensitivities and accuracies as high as 96.0%, 95.0% and 95.5%, respectively, were achieved. Various pretreatments, such as standard normal variate, mean centring and a Savitzky-Golay filter with seven smoothing points, were used. The optimal wavelengths for classification were mainly correlated with lipids, although some contribution from minor constituents, such as proteins and carbohydrates, was also observed. Near infrared spectroscopy could classify hazelnut according to the PDO 'Nocciola Romana' designation. Thus, the experimentation lays the foundations for a rapid, online, authentication system for hazelnut. However, model robustness should be improved taking into account agro-pedo-climatic growing conditions. © 2014 Society of Chemical Industry.

  7. Hydrogen, oxygen and hydroxyl on porous silicon surface: A joint density-functional perturbation theory and infrared spectroscopy approach

    International Nuclear Information System (INIS)

    Alfaro, Pedro; Palavicini, Alessio; Wang, Chumin

    2014-01-01

    Based on the density functional perturbation theory (DFPT), infrared absorption spectra of porous silicon are calculated by using an ordered pore model, in which columns of silicon atoms are removed along the [001] direction and dangling bonds are initially saturated with hydrogen atoms. When these atoms on the pore surface are gradually replaced by oxygen ones, the ab-initio infrared absorption spectra reveal oxygen, hydroxyl, and coupled hydrogen–oxygen vibrational modes. In a parallel way, freestanding porous silicon samples were prepared by using electrochemical etching and they were further thermally oxidized in a dry oxygen ambient. Fourier transform infrared spectroscopy was used to investigate the surface modifications caused by oxygen adsorption. In particular, the predicted hydroxyl and oxygen bound to the silicon pore surface are confirmed. Finally, a global analysis of measured transmittance spectra has been performed by means of a combined DFPT and thin-film optics approach. - Highlights: • The density functional perturbation theory is used to study infrared absorption. • An ordered pore model is used to investigate the oxidation in porous silicon (PSi). • Infrared transmittance spectra of oxidized PSi freestanding samples are measured

  8. Dual time-resolved temperature-jump fluorescence and infrared spectroscopy for the study of fast protein dynamics.

    Science.gov (United States)

    Davis, Caitlin M; Reddish, Michael J; Dyer, R Brian

    2017-05-05

    Time-resolved temperature-jump (T-jump) coupled with fluorescence and infrared (IR) spectroscopy is a powerful technique for monitoring protein dynamics. Although IR spectroscopy of the polypeptide amide I mode is more technically challenging, it offers complementary information because it directly probes changes in the protein backbone, whereas, fluorescence spectroscopy is sensitive to the environment of specific side chains. With the advent of widely tunable quantum cascade lasers (QCL) it is possible to efficiently probe multiple IR frequencies with high sensitivity and reproducibility. Here we describe a dual time-resolved T-jump fluorescence and IR spectrometer and its application to study protein folding dynamics. A Q-switched Ho:YAG laser provides the T-jump source for both time-resolved IR and fluorescence spectroscopy, which are probed by a QCL and Ti:Sapphire laser, respectively. The Ho:YAG laser simultaneously pumps the time-resolved IR and fluorescence spectrometers. The instrument has high sensitivity, with an IR absorbance detection limit of jump induced difference spectrum from 50ns to 0.5ms. This study demonstrates the power of the dual time-resolved T-jump fluorescence and IR spectroscopy to resolve complex folding mechanisms by complementary IR absorbance and fluorescence measurements of protein dynamics. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Identification of the traditional Tibetan medicine "Shaji" and their different extracts through tri-step infrared spectroscopy

    Science.gov (United States)

    Liu, Yue; Li, Jingyi; Fan, Gang; Sun, Suqin; Zhang, Yuxin; Zhang, Yi; Tu, Ya

    2016-11-01

    Hippophae rhamnoides subsp. sinensis Rousi, Hippophae gyantsensis (Rousi) Y. S. Lian, Hippophae neurocarpa S. W. Liu & T. N. He and Hippophae tibetana Schlechtendal are typically used under one name "Shaji", to treat cardiovascular diseases and lung disorders in Tibetan medicine (TM). A complete set of infrared (IR) macro-fingerprints of these four Hippophae species should be characterized and compared simply, accurately, and in detail for identification. In the present study, tri-step IR spectroscopy, which included Fourier transform IR (FT-IR) spectroscopy, second derivative IR (SD-IR) spectroscopy and two-dimensional correlation IR (2D-IR) spectroscopy, was employed to discriminate the four Hippophae species and their corresponding extracts using different solvents. The relevant spectra exhibited the holistic chemical compositions and variations. Flavonoids, fatty acids and sugars were found to be the main chemical components. Characteristic peak positions, intensities and shapes derived from FT-IR, SD-IR and 2D-IR spectra provided valuable information for sample discrimination. Principal component analysis (PCA) of spectral differences was performed to illustrate the objective identification. Results showed that the species and their extracts can be clearly distinguished. Thus, a quick, precise and effective tri-step IR spectroscopy combined with PCA can be applied to identify and discriminate medicinal materials and their extracts in TM research.

  10. 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.

  11. 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.

  12. HHT diagnosis by Mid-infrared spectroscopy and artificial neural network analysis.

    Science.gov (United States)

    Lux, Andreas; Müller, Ralf; Tulk, Mark; Olivieri, Carla; Zarrabeita, Roberto; Salonikios, Theresia; Wirnitzer, Bernhard

    2013-06-27

    The vascular disorder Hereditary Hemorrhagic Telangiectasia (HHT) is in general an inherited disease caused by mutations in the TGF-β/BMP receptors endoglin or ALK1 or in rare cases by mutations of the TGF-β signal transducer protein Smad4 leading to the combined syndrome of juvenile polyposis and HHT. HHT is characterized by several clinical symptoms like spontaneous and recurrent epistaxis, multiple telangiectases at sites like lips, oral cavity, fingers, nose, and visceral lesions like gastrointestinal telangiectasia, pulmonary, hepatic, cerebral or spinal arteriovenous malformations. The disease shows an inter- and intra-family variability in penetrance as well as symptoms from mild to life threatening. Penetrance is also depending on age. Diagnosis of the disease is based on the presence of some of the listed symptoms or by genetic testing. HHT diagnosis is laborious, time consuming, costly and sometimes uncertain. Not all typical symptoms may be present, especially at a younger age, and genetic testing does not always identify the disease causing mutation. Infrared (IR) spectroscopy was investigated as a potential alternative to the current diagnostic methods. IR-spectra were obtained by Fourier-transform Mid-IR spectroscopy from blood plasma from HHT patients and a healthy control group. Spectral data were mathematically processed and subsequently classified and analysed by artificial neural network (ANN) analyses and by visual analysis of scatter plots of the dominant principal components. The analyses showed that for HHT a disease specific IR-spectrum exists that is significantly different from the control group. Furthermore, at the current stage with the here used methods, HHT can be diagnosed by Mid-IR-spectroscopy in combination with ANN analysis with a sensitivity and specificity of at least 95%. Visual analysis of PCA scatter plots revealed an inter class variation of the HHT group. IR-spectroscopy in combination with ANN analysis can be considered

  13. Wireless Mid-Infrared Spectroscopy Sensor Network for Automatic Carbon Dioxide Fertilization in a Greenhouse Environment

    Directory of Open Access Journals (Sweden)

    Jianing Wang

    2016-11-01

    Full Text Available In this paper, a wireless mid-infrared spectroscopy sensor network was designed and implemented for carbon dioxide fertilization in a greenhouse environment. A mid-infrared carbon dioxide (CO2 sensor based on non-dispersive infrared (NDIR with the functionalities of wireless communication and anti-condensation prevention was realized as the sensor node. Smart transmission power regulation was applied in the wireless sensor network, according to the Received Signal Strength Indication (RSSI, to realize high communication stability and low-power consumption deployment. Besides real-time monitoring, this system also provides a CO2 control facility for manual and automatic control through a LabVIEW platform. According to simulations and field tests, the implemented sensor node has a satisfying anti-condensation ability and reliable measurement performance on CO2 concentrations ranging from 30 ppm to 5000 ppm. As an application, based on the Fuzzy proportional, integral, and derivative (PID algorithm realized on a LabVIEW platform, the CO2 concentration was regulated to some desired concentrations, such as 800 ppm and 1200 ppm, in 30 min with a controlled fluctuation of <±35 ppm in an acre of greenhouse.

  14. 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.

  15. 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.

  16. Determination of carbohydrates present in Saccharomyces cerevisiae using mid-infrared spectroscopy and partial least squares regression

    OpenAIRE

    Plata, Maria R.; Koch, Cosima; Wechselberger, Patrick; Herwig, Christoph; Lendl, Bernhard

    2013-01-01

    A fast and simple method to control variations in carbohydrate composition of Saccharomyces cerevisiae, baker's yeast, during fermentation was developed using mid-infrared (mid-IR) spectroscopy. The method allows for precise and accurate determinations with minimal or no sample preparation and reagent consumption based on mid-IR spectra and partial least squares (PLS) regression. The PLS models were developed employing the results from reference analysis of the yeast cells. The reference anal...

  17. 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

  18. Vapor-phase infrared laser spectroscopy: from gas sensing to forensic urinalysis.

    Science.gov (United States)

    Bartlome, Richard; Rey, Julien M; Sigrist, Markus W

    2008-07-15

    Numerous gas-sensing devices are based on infrared laser spectroscopy. In this paper, the technique is further developed and, for the first time, applied to forensic urinalysis. For this purpose, a difference frequency generation laser was coupled to an in-house-built, high-temperature multipass cell (HTMC). The continuous tuning range of the laser was extended to 329 cm(-1) in the fingerprint C-H stretching region between 3 and 4 microm. The HTMC is a long-path absorption cell designed to withstand organic samples in the vapor phase (Bartlome, R.; Baer, M.; Sigrist, M. W. Rev. Sci. Instrum. 2007, 78, 013110). Quantitative measurements were taken on pure ephedrine and pseudoephedrine vapors. Despite featuring similarities, the vapor-phase infrared spectra of these diastereoisomers are clearly distinguishable with respect to a vibrational band centered at 2970.5 and 2980.1 cm(-1), respectively. Ephedrine-positive and pseudoephedrine-positive urine samples were prepared by means of liquid-liquid extraction and directly evaporated in the HTMC without any preliminary chromatographic separation. When 10 or 20 mL of ephedrine-positive human urine is prepared, the detection limit of ephedrine, prohibited in sports as of 10 microg/mL, is 50 or 25 microg/mL, respectively. The laser spectrometer has room for much improvement; its potential is discussed with respect to doping agents detection.

  19. The Spitzer Infrared Nearby Galaxies Survey: A High-Resolution Spectroscopy Anthology

    Science.gov (United States)

    Dale, Daniel A.; SINGS Team

    2009-05-01

    Results from high resolution mid-infrared spectroscopy are presented for 155 nuclear and extranuclear regions from SINGS. The SINGS sample shows a wide range in the ratio of [SIII]18.71/[SIII]33.48, but the average ratio of the ensemble indicates a typical interstellar electron density of 300--400 cm-3 on 23"x15" scales and 500--600 cm-3 using 11"x9" apertures, independent of whether the region probed is a star-forming nuclear, a star-forming extranuclear, or an AGN environment. Evidence is provided that variations in gas-phase metallicity play an important role in driving variations in radiation field hardness, as indicated by [NeIII]15.56/[NeII]12.81, for regions powered by star formation. Conversely, the radiation hardness for galaxy nuclei powered by accretion around a massive black hole is independent of metal abundance. Furthermore, for metal-rich environments AGN are distinguishable from star-forming regions by significantly larger [NeIII]15.56/[NeII]12.81 ratios. Finally, [FeII]25.99/[NeII]12.81 versus [SiII]34.82/[SIII]33.48 also provides an empirical method for discerning AGN from normal star-forming sources. However, similar to [NeIII]15.56/[NeII]12.81, these mid-infrared line ratios lose their AGN/star-formation diagnostic powers for very low metallicity star-forming systems with hard radiation fields.

  20. Analysis and identification of two similar traditional Chinese medicines by using a three-stage infrared spectroscopy: Ligusticum chuanxiong, Angelica sinensis and their different extracts

    Science.gov (United States)

    Xiang, Li; Wang, Jingjuan; Zhang, Guijun; Rong, Lixin; Wu, Haozhong; Sun, Suqin; Guo, Yizhen; Yang, Yanfang; Lu, Lina; Qu, Lei

    2016-11-01

    Rhizoma Chuanxiong (CX) and Radix Angelica sinensis (DG) are very important Traditional Chinese Medicine (TCM) and usually used in clinic. They both are from the Umbelliferae family, and have almost similar chemical constituents with each other. It is complicated, time-consuming and laborious to discriminate them by using the chromatographic methods such as high performance liquid chromatography (HPLC) and gas chromatography (GC). Therefore, to find a fast, applicable and effective identification method for two herbs is urged in quality research of TCM. In this paper, by using a three-stage infrared spectroscopy (Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2D-IR)), we analyzed and discriminated CX, DG and their different extracts (aqueous extract, alcoholic extract and petroleum ether extract). In FT-IR, all the CX and DG samples' spectra seemed similar, but they had their own unique macroscopic fingerprints to identify. Through comparing with the spectra of sucrose and the similarity calculation, we found the content of sucrose in DG raw materials was higher than in CX raw materials. The significant differences in alcoholic extract appeared that in CX alcoholic extract, the peaks at 1743 cm-1 was obviously stronger than the peak at same position in DG alcoholic extract. Besides in petroleum ether extract, we concluded CX contained much more ligustilide than DG by the similarity calculation. With the function of SD-IR, some tiny differences were amplified and overlapped peaks were also unfolded in FT-IR. In the range of 1100-1175 cm-1, there were six peaks in the SD-IR spectra of DG and the intensity, shape and location of those six peaks were similar to that of sucrose, while only two peaks could be observed in that of CX and those two peaks were totally different from sucrose in shape and relative intensity. This result was consistent with that of the