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Sample records for infrared 2d ir

  1. 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.

  2. 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.

  3. Chemical profiling and adulteration screening of Aquilariae Lignum Resinatum by Fourier transform infrared (FT-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy.

    Science.gov (United States)

    Qu, Lei; Chen, Jian-Bo; Zhang, Gui-Jun; Sun, Su-Qin; Zheng, Jing

    2017-03-05

    As a kind of expensive perfume and valuable herb, Aquilariae Lignum Resinatum (ALR) is often adulterated for economic motivations. In this research, Fourier transform infrared (FT-IR) spectroscopy is employed to establish a simple and quick method for the adulteration screening of ALR. First, the principal chemical constituents of ALR are characterized by FT-IR spectroscopy at room temperature and two-dimensional correlation infrared (2D-IR) spectroscopy with thermal perturbation. Besides the common cellulose and lignin compounds, a certain amount of resin is the characteristic constituent of ALR. Synchronous and asynchronous 2D-IR spectra indicate that the resin (an unstable secondary metabolite) is more sensitive than cellulose and lignin (stable structural constituents) to the thermal perturbation. Using a certified ALR sample as the reference, the infrared spectral correlation threshold is determined by 30 authentic samples and 6 adulterated samples. The spectral correlation coefficient of an authentic ALR sample to the standard reference should be not less than 0.9886 (p=0.01). Three commercial adulterated ALR samples are identified by the correlation threshold. Further interpretation of the infrared spectra of the adulterated samples indicates the common adulterating methods - counterfeiting with other kind of wood, adding ingredient such as sand to increase the weight, and adding the cheap resin such as rosin to increase the content of resin compounds. Results of this research prove that FT-IR spectroscopy can be used as a simple and accurate quality control method of ALR. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Mid-Infrared Spectral Properties of IR QSOs

    International Nuclear Information System (INIS)

    Xia, X. Y.; Cao, C.; Mao, S.; Deng, Z. G.

    2008-01-01

    We analyse mid-infrared (MIR) spectroscopic properties for 19 ultra-luminous infrared quasars (IR QSOs) in the local universe based on the spectra from the Infrared Spectrograph on board the Spitzer Space Telescope. The MIR properties of IR QSOs are compared with those of optically-selected Palomar-Green QSOs (PG QSOs) and ultra-luminous infrared galaxies (ULIRGs). The average MIR spectral features from ∼5 to 30 μm, including the spectral slopes, 6.2 μm PAH emission strengths and [NeII] 12.81 μm luminosities of IR QSOs, differ from those of PG QSOs. In contrast, IR QSOs and ULIRGs have comparable PAH and [NeII] luminosities. These results are consistent with IR QSOs being at a transitional stage from ULIRGs to classical QSOs. We also find the correlation between the EW (PAH 6.2 μm) and outflow velocities suggests that star formation activities are suppressed by feedback from AGNs and/or supernovae.

  5. New infrared observations of IRS 1, IRS 3, and the adjacent nebula in the OMC-2 cluster

    International Nuclear Information System (INIS)

    Pendelton, Y.; Werner, M.; Dinerstein, H.

    1984-01-01

    Recent reports show that near infrared reflection nebulae are often observed around embedded protostellar objects. New observations are here reported of the infrared cluster of low luminosity protostars in Orion Molecular Cloud 2 (OMC2). It has been determined that the asymmetric distribution of the extended emission seen about IRS1 is in fact another infrared reflection nebula. Observations of near infrared polarimetry, photometry, and spectrophotometry were carried out at the NASA Infrared Telescope Facility October 1982 and January 1983. (author)

  6. Rapid identification of Pterocarpus santalinus and Dalbergia louvelii by FTIR and 2D correlation IR spectroscopy

    Science.gov (United States)

    Zhang, Fang-Da; Xu, Chang-Hua; Li, Ming-Yu; Huang, An-Min; Sun, Su-Qin

    2014-07-01

    Since Pterocarpus santalinus and Dalbergia louvelii, which are of precious Rosewood, are very similar in their appearance and anatomy characteristics, cheaper Hongmu D. louvelii is often illegally used to impersonate valuable P. santalinus, especially in Chinese furniture manufacture. In order to develop a rapid and effective method for easy confused wood furniture differentiation, we applied tri-step identification method, i.e., conventional infrared spectroscopy (FT-IR), second derivative infrared (SD-IR) spectroscopy and two-dimensional correlation infrared (2DCOS-IR) spectroscopy to investigate P. santalinus and D. louvelii furniture. According to FT-IR and SD-IR spectra, it has been found two unconditional stable difference at 848 cm-1 and 700 cm-1 and relative stable differences at 1735 cm-1, 1623 cm-1, 1614 cm-1, 1602 cm-1, 1509 cm-1, 1456 cm-1, 1200 cm-1, 1158 cm-1, 1055 cm-1, 1034 cm-1 and 895 cm-1 between D. louvelii and P. santalinus IR spectra. The stable discrepancy indicates that the category of extractives is different between the two species. Besides, the relative stable differences imply that the content of holocellulose in P. santalinus is more than that of D. louvelii, whereas the quantity of extractives in D. louvelii is higher. Furthermore, evident differences have been observed in their 2DCOS-IR spectra of 1550-1415 cm-1 and 1325-1030 cm-1. P. santalinus has two strong auto-peaks at 1459 cm-1 and 1467 cm-1, three mid-strong auto-peaks at 1518 cm-1, 1089 cm-1 and 1100 cm-1 and five weak auto-peaks at 1432 cm-1, 1437 cm-1, 1046 cm-1, 1056 cm-1 and 1307 cm-1 while D. louvelii has four strong auto-peaks at 1465 cm-1, 1523 cm-1, 1084 cm-1 and 1100 cm-1, four mid-strong auto-peaks at 1430 cm-1, 1499 cm-1, 1505 cm-1 and 1056 cm-1 and two auto-peaks at 1540 cm-1 and 1284 cm-1. This study has proved that FT-IR integrated with 2DCOS-IR could be applicable for precious wood furniture authentication in a direct, rapid and holistic manner.

  7. 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.

  8. Volatility-dependent 2D IR correlation analysis of traditional Chinese medicine ‘Red Flower Oil’ preparation from different manufacturers

    Science.gov (United States)

    Wu, Yan-Wen; Sun, Su-Qin; Zhou, Qun; Tao, Jia-Xun; Noda, Isao

    2008-06-01

    As a traditional Chinese medicine (TCM), 'Red Flower Oil' preparation is widely used as a household remedy in China and Southeast Asia. Usually, the preparation is a mixture of several plant essential oils with different volatile features, such as wintergreen oil, turpentine oil and clove oil. The proportions of these plant essential oils in 'Red Flower Oil' vary from different manufacturers. Thus, it is important to develop a simple and rapid evaluation method for quality assurance of the preparations. Fourier transform infrared (FT-IR) was applied and two-dimensional correlation infrared spectroscopy (2D IR) based on the volatile characteristic of samples was used to enhance the resolution of FT-IR spectra. 2D IR technique could, not only easily provide the composition and their volatile sequences in 'Red flower Oil' preparations, but also rapidly discriminate the subtle differences in products from different manufacturers. Therefore, FT-IR combined with volatility-dependent 2D IR correlation analysis provides a very fast and effective method for the quality control of essential oil mixtures in TCM.

  9. IL 6: 2D-IR spectroscopy: chemistry and biophysics in real time

    International Nuclear Information System (INIS)

    Bredenbeck, Jens

    2010-01-01

    Pulsed multidimensional experiments, daily business in the field of NMR spectroscopy, have been demonstrated only relatively recently in IR spectroscopy. Similar as nuclear spins in multidimensional NMR, molecular vibrations are employed in multidimensional IR experiments as probes of molecular structure and dynamics, albeit with femtosecond time resolution. Different types of multidimensional IR experiments have been implemented, resembling basic NMR experiments such as NOESY, COSY and EXSY. In contrast to one-dimensional linear spectroscopy, such multidimensional experiments reveal couplings and correlations of vibrations, which are closely linked to molecular structure and its change in time. The use of mixed IR/VIS pulse sequences further extends the potential of multidimensional IR spectroscopy, enabling studies of ultrafast non-equilibrium processes as well as surface specific, highly sensitive experiments. A UV/VIS pulse preceding the IR pulse sequence can be used to prepare the system under study in a non-equilibrium state. 2D-IR snapshots of the evolving non-equilibrium system are then taken, for example during a photochemical reaction or during the photo-cycle of a light sensitive protein. Preparing the system in a non-equilibrium state by UV/Vis excitation during the IR pulse sequence allows for correlating states of reactant and product of the light triggered process via their 2D-IR cross peaks - a technique that has been used to map the connectivity between different binding sites of a ligand as it migrates through a protein. Introduction of a non-resonant VIS pulse at the end of the IR part of the experiment allows to selectively up-convert the infrared signal of interfacial molecules to the visible spectral range by sum frequency generation. In this way, femtosecond interfacial 2D-IR spectroscopy can be implemented, achieving sub-monolayer sensitivity. (author)

  10. Characterization by Fourier transform infrared spectroscopy (FT-IR) and 2D IR correlation spectroscopy of a carbosilane dendrimer with peripheral ammonium groups

    Energy Technology Data Exchange (ETDEWEB)

    Popescu, Maria-Cristina, E-mail: cpopescu@icmpp.ro [' Petru Poni' Institute of Macromolecular Chemistry (Romania); Gomez, Rafael; Mata, Fco Javier de la; Rasines, Beatriz [Universidad de Alcala, Departamento de Quimica Inorganica (Spain); Simionescu, Bogdan C. [' Petru Poni' Institute of Macromolecular Chemistry (Romania)

    2013-06-15

    Fourier transform infrared spectroscopy and 2D correlation spectroscopy were used to study the microstructural changes occurring on heating of a new carbosilane dendrimer with peripheral ammonium groups. Temperature-dependent spectral variations in the 3,010-2,710, 1,530-1,170, and 1,170-625 cm{sup -1} regions were monitored during the heating process. The dependence, on temperature, of integral absorptions and position of spectral bands was established and the spectral modifications associated with molecular conformation rearrangements, allowing molecular shape changes, were found. Before 180 Degree-Sign C, the studied carbosilane dendrimer proved to be stable, while at higher temperatures it oxidizes and Si-O groups appear. 2D IR correlation spectroscopy gives new information about the effect of temperature on the structure and dynamics of the system. Synchronous and asynchronous spectra indicate that, at low temperature, conformational changes of CH{sub 3} and CH{sub 3}-N{sup +} groups take place first. With increasing temperature, the intensity variation of the CH{sub 2}, C-N, Si-C and C-C groups from the dendritic core is faster than that of the terminal units. This indicates that, with increasing temperature, the segments of the dendritic core obtain enough energy to change their conformation more easily as compared to the terminal units, due to their internal flexibility.

  11. Characterization by Fourier transform infrared spectroscopy (FT-IR) and 2D IR correlation spectroscopy of a carbosilane dendrimer with peripheral ammonium groups

    International Nuclear Information System (INIS)

    Popescu, Maria-Cristina; Gómez, Rafael; Mata, Fco Javier de la; Rasines, Beatriz; Simionescu, Bogdan C.

    2013-01-01

    Fourier transform infrared spectroscopy and 2D correlation spectroscopy were used to study the microstructural changes occurring on heating of a new carbosilane dendrimer with peripheral ammonium groups. Temperature-dependent spectral variations in the 3,010–2,710, 1,530–1,170, and 1,170–625 cm −1 regions were monitored during the heating process. The dependence, on temperature, of integral absorptions and position of spectral bands was established and the spectral modifications associated with molecular conformation rearrangements, allowing molecular shape changes, were found. Before 180 °C, the studied carbosilane dendrimer proved to be stable, while at higher temperatures it oxidizes and Si–O groups appear. 2D IR correlation spectroscopy gives new information about the effect of temperature on the structure and dynamics of the system. Synchronous and asynchronous spectra indicate that, at low temperature, conformational changes of CH 3 and CH 3 –N + groups take place first. With increasing temperature, the intensity variation of the CH 2 , C–N, Si–C and C–C groups from the dendritic core is faster than that of the terminal units. This indicates that, with increasing temperature, the segments of the dendritic core obtain enough energy to change their conformation more easily as compared to the terminal units, due to their internal flexibility.

  12. 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.

  13. 2D IR spectra of cyanide in water investigated by molecular dynamics simulations

    Science.gov (United States)

    Lee, Myung Won; Carr, Joshua K.; Göllner, Michael; Hamm, Peter; Meuwly, Markus

    2013-01-01

    Using classical molecular dynamics simulations, the 2D infrared (IR) spectroscopy of CN− solvated in D2O is investigated. Depending on the force field parametrizations, most of which are based on multipolar interactions for the CN− molecule, the frequency-frequency correlation function and observables computed from it differ. Most notably, models based on multipoles for CN− and TIP3P for water yield quantitatively correct results when compared with experiments. Furthermore, the recent finding that T 1 times are sensitive to the van der Waals ranges on the CN− is confirmed in the present study. For the linear IR spectrum, the best model reproduces the full widths at half maximum almost quantitatively (13.0 cm−1 vs. 14.9 cm−1) if the rotational contribution to the linewidth is included. Without the rotational contribution, the lines are too narrow by about a factor of two, which agrees with Raman and IR experiments. The computed and experimental tilt angles (or nodal slopes) α as a function of the 2D IR waiting time compare favorably with the measured ones and the frequency fluctuation correlation function is invariably found to contain three time scales: a sub-ps, 1 ps, and one on the 10-ps time scale. These time scales are discussed in terms of the structural dynamics of the surrounding solvent and it is found that the longest time scale (≈10 ps) most likely corresponds to solvent exchange between the first and second solvation shell, in agreement with interpretations from nuclear magnetic resonance measurements.

  14. Towards a Molecular Movie: Real Time Observation of Hydrogen Bond Breaking by Transient 2D-IR Spectroscopy in a Cyclic Peptide

    Science.gov (United States)

    Kolano, Christoph; Helbing, Jan; Sander, Wolfram; Hamm, Peter

    Transient two-dimensional infrared spectroscopy (T2D-IR) has been used to observe in real time the non-equilibrium structural dynamics of intramolecular hydrogen bond breaking in a small cyclic disulfide-bridged peptide.

  15. AMA Conferences 2015. SENSOR 2015. 17th international conference on sensors and measurement technology. IRS2 2015. 14th international conference on infrared sensors and systems. Proceedings

    International Nuclear Information System (INIS)

    2015-01-01

    This meeting paper contains presentations of two conferences: SENSOR 2015 and IRS 2 (= International conference on InfraRed Sensors and systems). The first part of SENSOR 2015 contains the following chapters: (A) SENSOR PRINCIPLES: A.1: Mechanical sensors; A.2: Optical sensors; A.3: Ultrasonic sensors; A.4: Microacoustic sensors; A.5: Magnetic sensors; A.6: Impedance sensors; A.7: Gas sensors; A.8: Flow sensors; A.9: Dimensional measurement; A.10: Temperature and humidity sensors; A.11: Chemosensors; A.12: Biosensors; A.13: Embedded sensors; A.14: Sensor-actuator systems; (B) SENSOR TECHNOLOGY: B.1: Sensor design; B.2: Numerical simulation of sensors; B.3: Sensor materials; B.4: MEMS technology; B.5: Micro-Nano-Integration; B.6: Packaging; B.7: Materials; B.8: Thin films; B.9: Sensor production; B.10: Sensor reliability; B.11: Calibration and testing; B.12: Optical fibre sensors. (C) SENSOR ELECTRONICS AND COMMUNICATION: C.1: Sensor electronics; C.2: Sensor networks; C.3: Wireless sensors; C.4: Sensor communication; C.5: Energy harvesting; C.6: Measuring systems; C.7: Embedded systems; C.8: Self-monitoring and diagnosis; (D) APPLICATIONS: D.1: Medical measuring technology; D.2: Ambient assisted living; D.3: Process measuring technology; D.4: Automotive; D.5: Sensors in energy technology; D.6: Production technology; D.7: Security technology; D.8: Smart home; D.9: Household technology. The second part with the contributions of the IRS 2 2015 is structured as follows: (E) INFRARED SENSORS: E.1: Photon detectors; E.2: Thermal detectors; E.3: Cooled detectors; E.4: Uncooled detectors; E.5: Sensor modules; E.6: Sensor packaging. (G) INFRARED SYSTEMS AND APPLICATIONS: G.1: Thermal imaging; G.2: Pyrometry / contactless temperature measurement; G.3: Gas analysis; G.4: Spectroscopy; G.5: Motion control and presence detection; G.6: Security and safety monitoring; G.7: Non-destructive testing; F: INFRARED SYSTEM COMPONENTS: F.1: Infrared optics; F.2: Optical modulators; F.3

  16. AMA Conferences 2015. SENSOR 2015. 17th international conference on sensors and measurement technology. IRS{sup 2} 2015. 14th international conference on infrared sensors and systems. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    This meeting paper contains presentations of two conferences: SENSOR 2015 and IRS{sup 2} (= International conference on InfraRed Sensors and systems). The first part of SENSOR 2015 contains the following chapters: (A) SENSOR PRINCIPLES: A.1: Mechanical sensors; A.2: Optical sensors; A.3: Ultrasonic sensors; A.4: Microacoustic sensors; A.5: Magnetic sensors; A.6: Impedance sensors; A.7: Gas sensors; A.8: Flow sensors; A.9: Dimensional measurement; A.10: Temperature and humidity sensors; A.11: Chemosensors; A.12: Biosensors; A.13: Embedded sensors; A.14: Sensor-actuator systems; (B) SENSOR TECHNOLOGY: B.1: Sensor design; B.2: Numerical simulation of sensors; B.3: Sensor materials; B.4: MEMS technology; B.5: Micro-Nano-Integration; B.6: Packaging; B.7: Materials; B.8: Thin films; B.9: Sensor production; B.10: Sensor reliability; B.11: Calibration and testing; B.12: Optical fibre sensors. (C) SENSOR ELECTRONICS AND COMMUNICATION: C.1: Sensor electronics; C.2: Sensor networks; C.3: Wireless sensors; C.4: Sensor communication; C.5: Energy harvesting; C.6: Measuring systems; C.7: Embedded systems; C.8: Self-monitoring and diagnosis; (D) APPLICATIONS: D.1: Medical measuring technology; D.2: Ambient assisted living; D.3: Process measuring technology; D.4: Automotive; D.5: Sensors in energy technology; D.6: Production technology; D.7: Security technology; D.8: Smart home; D.9: Household technology. The second part with the contributions of the IRS{sup 2} 2015 is structured as follows: (E) INFRARED SENSORS: E.1: Photon detectors; E.2: Thermal detectors; E.3: Cooled detectors; E.4: Uncooled detectors; E.5: Sensor modules; E.6: Sensor packaging. (G) INFRARED SYSTEMS AND APPLICATIONS: G.1: Thermal imaging; G.2: Pyrometry / contactless temperature measurement; G.3: Gas analysis; G.4: Spectroscopy; G.5: Motion control and presence detection; G.6: Security and safety monitoring; G.7: Non-destructive testing; F: INFRARED SYSTEM COMPONENTS: F.1: Infrared optics; F.2: Optical

  17. $β'_{IR}$ at an Infrared Fixed Point in Chiral Gauge Theories

    DEFF Research Database (Denmark)

    Ryttov, Thomas A.; Shrock, Robert

    2018-01-01

    We present scheme-independent calculations of the derivative of the beta function, denoted $\\beta'_{IR}$, at a conformally invariant infrared (IR) fixed point, in several asymptotically free chiral gauge theories, namely SO($4k+2$) with $2 \\le k \\le 4$ with respective numbers $N_f$ of fermions...

  18. 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…

  19. Parallel β-sheet vibrational couplings revealed by 2D IR spectroscopy of an isotopically labeled macrocycle: quantitative benchmark for the interpretation of amyloid and protein infrared spectra.

    Science.gov (United States)

    Woys, Ann Marie; Almeida, Aaron M; Wang, Lu; Chiu, Chi-Cheng; McGovern, Michael; de Pablo, Juan J; Skinner, James L; Gellman, Samuel H; Zanni, Martin T

    2012-11-21

    Infrared spectroscopy is playing an important role in the elucidation of amyloid fiber formation, but the coupling models that link spectra to structure are not well tested for parallel β-sheets. Using a synthetic macrocycle that enforces a two stranded parallel β-sheet conformation, we measured the lifetimes and frequency for six combinations of doubly (13)C═(18)O labeled amide I modes using 2D IR spectroscopy. The average vibrational lifetime of the isotope labeled residues was 550 fs. The frequencies of the labels ranged from 1585 to 1595 cm(-1), with the largest frequency shift occurring for in-register amino acids. The 2D IR spectra of the coupled isotope labels were calculated from molecular dynamics simulations of a series of macrocycle structures generated from replica exchange dynamics to fully sample the conformational distribution. The models used to simulate the spectra include through-space coupling, through-bond coupling, and local frequency shifts caused by environment electrostatics and hydrogen bonding. The calculated spectra predict the line widths and frequencies nearly quantitatively. Historically, the characteristic features of β-sheet infrared spectra have been attributed to through-space couplings such as transition dipole coupling. We find that frequency shifts of the local carbonyl groups due to nearest neighbor couplings and environmental factors are more important, while the through-space couplings dictate the spectral intensities. As a result, the characteristic absorption spectra empirically used for decades to assign parallel β-sheet secondary structure arises because of a redistribution of oscillator strength, but the through-space couplings do not themselves dramatically alter the frequency distribution of eigenstates much more than already exists in random coil structures. Moreover, solvent exposed residues have amide I bands with >20 cm(-1) line width. Narrower line widths indicate that the amide I backbone is solvent

  20. The structure of salt bridges between Arg(+) and Glu(-) in peptides investigated with 2D-IR spectroscopy: Evidence for two distinct hydrogen-bond geometries.

    Science.gov (United States)

    Huerta-Viga, Adriana; Amirjalayer, Saeed; Domingos, Sérgio R; Meuzelaar, Heleen; Rupenyan, Alisa; Woutersen, Sander

    2015-06-07

    Salt bridges play an important role in protein folding and in supramolecular chemistry, but they are difficult to detect and characterize in solution. Here, we investigate salt bridges between glutamate (Glu(-)) and arginine (Arg(+)) using two-dimensional infrared (2D-IR) spectroscopy. The 2D-IR spectrum of a salt-bridged dimer shows cross peaks between the vibrational modes of Glu(-) and Arg(+), which provide a sensitive structural probe of Glu(-)⋯Arg(+) salt bridges. We use this probe to investigate a β-turn locked by a salt bridge, an α-helical peptide whose structure is stabilized by salt bridges, and a coiled coil that is stabilized by intra- and intermolecular salt bridges. We detect a bidentate salt bridge in the β-turn, a monodentate one in the α-helical peptide, and both salt-bridge geometries in the coiled coil. To our knowledge, this is the first time 2D-IR has been used to probe tertiary side chain interactions in peptides, and our results show that 2D-IR spectroscopy is a powerful method for investigating salt bridges in solution.

  1. Infrared Spectroscopy of Gas-Phase M+(CO2)n (M = Co, Rh, Ir) Ion-Molecule Complexes.

    Science.gov (United States)

    Iskra, Andreas; Gentleman, Alexander S; Kartouzian, Aras; Kent, Michael J; Sharp, Alastair P; Mackenzie, Stuart R

    2017-01-12

    The structures of gas-phase M + (CO 2 ) n (M = Co, Rh, Ir; n = 2-15) ion-molecule complexes have been investigated using a combination of infrared resonance-enhanced photodissociation (IR-REPD) spectroscopy and density functional theory. The results provide insight into fundamental metal ion-CO 2 interactions, highlighting the trends with increasing ligand number and with different group 9 ions. Spectra have been recorded in the region of the CO 2 asymmetric stretch around 2350 cm -1 using the inert messenger technique and their interpretation has been aided by comparison with simulated infrared spectra of calculated low-energy isomeric structures. All vibrational bands in the smaller complexes are blue-shifted relative to the asymmetric stretch in free CO 2 , consistent with direct binding to the metal center dominated by charge-quadrupole interactions. For all three metal ions, a core [M + (CO 2 ) 2 ] structure is identified to which subsequent ligands are less strongly bound. No evidence is observed in this size regime for complete activation or insertion reactions.

  2. 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.

  3. AIRS/Aqua Level 1C Infrared (IR) resampled and corrected radiances V006

    Data.gov (United States)

    National Aeronautics and Space Administration — The AIRS Infrared (IR) level 1C data set contains AIRS infrared calibrated and geolocated radiances in W/m2/micron/ster. This data set is generated from AIRS level...

  4. 2D IR spectroscopy reveals the role of water in the binding of channel-blocking drugs to the influenza M2 channel

    International Nuclear Information System (INIS)

    Ghosh, Ayanjeet; Gai, Feng; Hochstrasser, Robin M.; Wang, Jun; DeGrado, William F.; Moroz, Yurii S.; Korendovych, Ivan V.; Zanni, Martin

    2014-01-01

    Water is an integral part of the homotetrameric M2 proton channel of the influenza A virus, which not only assists proton conduction but could also play an important role in stabilizing channel-blocking drugs. Herein, we employ two dimensional infrared (2D IR) spectroscopy and site-specific IR probes, i.e., the amide I bands arising from isotopically labeled Ala30 and Gly34 residues, to probe how binding of either rimantadine or 7,7-spiran amine affects the water dynamics inside the M2 channel. Our results show, at neutral pH where the channel is non-conducting, that drug binding leads to a significant increase in the mobility of the channel water. A similar trend is also observed at pH 5.0 although the difference becomes smaller. Taken together, these results indicate that the channel water facilitates drug binding by increasing its entropy. Furthermore, the 2D IR spectral signatures obtained for both probes under different conditions collectively support a binding mechanism whereby amantadine-like drugs dock in the channel with their ammonium moiety pointing toward the histidine residues and interacting with a nearby water cluster, as predicted by molecular dynamics simulations. We believe these findings have important implications for designing new anti-influenza drugs

  5. 2D IR spectroscopy reveals the role of water in the binding of channel-blocking drugs to the influenza M2 channel

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Ayanjeet, E-mail: ayanjeet@sas.upenn.edu, E-mail: gai@sas.upenn.edu; Gai, Feng, E-mail: ayanjeet@sas.upenn.edu, E-mail: gai@sas.upenn.edu; Hochstrasser, Robin M. [Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Wang, Jun; DeGrado, William F. [Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California 94143 (United States); Moroz, Yurii S.; Korendovych, Ivan V. [Department of Chemistry, Syracuse University, Syracuse, New York 13244 (United States); Zanni, Martin [Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706 (United States)

    2014-06-21

    Water is an integral part of the homotetrameric M2 proton channel of the influenza A virus, which not only assists proton conduction but could also play an important role in stabilizing channel-blocking drugs. Herein, we employ two dimensional infrared (2D IR) spectroscopy and site-specific IR probes, i.e., the amide I bands arising from isotopically labeled Ala30 and Gly34 residues, to probe how binding of either rimantadine or 7,7-spiran amine affects the water dynamics inside the M2 channel. Our results show, at neutral pH where the channel is non-conducting, that drug binding leads to a significant increase in the mobility of the channel water. A similar trend is also observed at pH 5.0 although the difference becomes smaller. Taken together, these results indicate that the channel water facilitates drug binding by increasing its entropy. Furthermore, the 2D IR spectral signatures obtained for both probes under different conditions collectively support a binding mechanism whereby amantadine-like drugs dock in the channel with their ammonium moiety pointing toward the histidine residues and interacting with a nearby water cluster, as predicted by molecular dynamics simulations. We believe these findings have important implications for designing new anti-influenza drugs.

  6. Experimental bandstructure of the 5 d transition metal oxide IrO2

    Science.gov (United States)

    Kawasaki, Jason; Nie, Yuefeng; Uchida, Masaki; Schlom, Darrell; Shen, Kyle

    2015-03-01

    In the 5 d iridium oxides the close energy scales of spin-orbit coupling and electron-electron correlations lead to emergent quantum phenomena. Much research has focused on the ternary iridium oxides, e.g. the Ruddlesden-Poppers An + 1BnO3 n + 1 , which exhibit behavior from metal to antiferromagnetic insulator ground states, share common features with the cuprates, and may host a number of topological phases. The binary rutile IrO2 is another important 5 d oxide, which has technological importance for spintronics due to its large spin Hall effect and also applications in catalysis. IrO2 is expected to share similar physics as its perovskite-based cousins; however, due to bond-length distortions of the IrO6 octahedra in the rutile structure, the extent of similarities remains an open question. Here we use angle-resolved photoemission spectroscopy to perform momentum-resolved measurements of the electronic structure of IrO2 . IrO2 thin films were grown by molecular beam epitaxy on TiO2 (110) substrates using an Ir e-beam source and distilled ozone. Films were subsequently transferred through ultrahigh vacuum to a connected ARPES system. Combined with first-principles calculations we explore the interplay of spin-orbit coupling and correlations in IrO2 .

  7. Cloud2IR: Infrared thermography and environmental sensors integrated in an autonomoussystem for long term monitoring of structures

    Science.gov (United States)

    Crinière, Antoine; Dumoulin, Jean; Mevel, Laurent; Andrade-Barroso, Guillermo

    2016-04-01

    acquisition scenario the local storage management and the network management through SFTP or SOAP for the OGC frame. The data side only need an XML configuration file and if a configuration change occurs in time the system is automatically restarted with the new value. Cloud2IR has been deployed on field since several Monthat the SenseCity outdoor test bed in Marne La Vallée (France)[4]. The next step will be the full standardisation of the system and possibly the full separation between the sensor side and the data side which can be seen at term as an external framework. References: [1] A Crinière, J Dumoulin, L Mevel, G Andrade-Barosso, M Simonin. The Cloud2SM Project.European Geosciences Union General Assembly (EGU2015), Apr 2015, Vienne, Austria. 2015. [2] J Dumoulin, A Criniere, and R Averty. The detection and thermal characterization of the inner structure of the 'musmeci' bridge deck by infrared thermography monitoring. Journal Of Geophysics And Engineering doi:10.1088/1742-2132/10/6/064003, Vol 10, 2013. [3] J Dumoulin, R Averty. Development of an infrared system coupled with a weather station for real time atmospheric corrections using GPU computing: Application to bridge monitoring, in Proc of 11 th International Conference on Quantitative InfraRed Thermography, Naples Italy, 2012. [4] F Derkx, B Lebental, T Bourouina, Frédéric B, C Cojocaru, and al..The Sense-City project.XVIIIth Symposium on Vibrations, Shocks and Noise, Jul 2012, France. 9p, 2012.

  8. Exploration of the Infrared Sensitivity for a ZnSe Electrode of an IR Image Converter

    Science.gov (United States)

    Kurt, H. Hilal

    2018-05-01

    Significant improvement has been carried out in the field of the II-VI group semiconductor device technology. Semiconductors based on the II-VI group are attractive due to their alternative uses for thermal imaging systems and photonic applications. This study focuses on experimental work on the optical, electrical and structural characterization of an infrared (IR) photodetector zinc selenide (ZnSe). In addition, the IR sensitivity of the ZnSe has primarily been investigated by exploiting the IR responses of the material for various gas pressures, p, and interelectrode distances, d, in the IR converter. The experimental findings include the results of plasma current and plasma discharge emission under various illumination conditions in the IR region. The electron density distributions inside the gas discharge gap have also been simulated in two-dimensional media. Experimentally, the current-voltage, current-time, and discharge light emission plots are produced for a wide experimental parameter range. Consequently, the structural and optical properties have been studied through atomic force microscopy and Fourier-transform infrared spectroscopy techniques to obtain a comprehensive knowledge of the material.

  9. IR and visible luminescence studies in the infrared multiphoton dissociation of 1,2-dibromo-1,1-difluoroethane

    Science.gov (United States)

    Pushpa, K. K.; Kumar, Awadhesh; Vatsa, R. K.; Naik, P. D.; Annaji Rao, K.; Mittal, J. P.; Parthasarathy, V.; Sarkar, S. K.

    1995-07-01

    The infrared multiphoton dissociation of 1,2-dibromo-1,1-difluoroethane gives rise to IR and visible luminescence. Vibrationally excited parent molecules dissociate via two primary channels yielding bromine and vibrationally excited HBr. The strong visible emission observed between 350 to 750 nm has been assigned to electronically excited carbene CF 2Br CH.

  10. 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.

  11. Infrared polarimetry of the reflection nebula near L 1551 IRS 5

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Tetsuya; Yamashita, Takuya; Sato, Shuji; Suzuki, Hiro; Hough, J H; Garden, R; Gatley, I

    1986-11-01

    The K-band polarization has been measured in the region extending 30 arcsec to the SW of L 1551 IRS5. The degree of polarization is exceptionally high, reaching approx. 67 per cent. The large polarizations and the azimuthal pattern of the position angles are attributed to scattering of infrared radiation from IRS5 by dust grains. The infrared brightness distribution resembles that of the optical nebulosity. It is proposed that infrared scattering occurs at the 'walls' of a cavity formed by the interaction of stellar winds with the ambient cloud.

  12. High-resolution far-infrared synchrotron FTIR spectrum of the ν12 band of formamide-d1 (DCONH2)

    Science.gov (United States)

    Tan, T. L.; Wu, Q. Y.; Ng, L. L.; Appadoo, Dominique R. T.; McNaughton, Don

    2018-05-01

    The spectrum of the ν12 band of formamide-d1 (DCONH2) was recorded using a synchrotron Fourier transform infrared (FTIR) spectrometer coupled to the Australian Synchrotron THz/Far-IR beamline, with an unapodized resolution of 0.00096 cm-1 in the 350-210 cm-1 region. For the first time, rovibrational constants up to five quartic and two sextic terms were derived for the v12 = 1 state through the fitting of a total of 2072 far-infrared transitions using Watson's A-reduced Hamiltonian in the Ir representation with a root-mean-square (rms) deviation of 0.000073 cm-1. The band centre of the ν12 band of DCONH2 was found to be 289.3327553(47) cm-1 although the experimental uncertainty was limited to ±0.0002 cm-1. Ground state rovibrational constants of DCONH2 up to five quartic and two sextic constants were derived from a fit of 847 ground state combination differences (GSCDs) obtained from the infrared transitions of the ν12 band, together with 6 previously reported microwave transitions, with a rms deviation of 0.000108 cm-1. The ground state rotational constants (A, B, and C) of DCONH2 were improved while the ground state centrifugal distortion constants were accurately obtained for the first time. The uncertainty of the measured infrared lines was estimated to be ±0.0002 cm-1. From the ground state rotational constants, the inertial defect of DCONH2 was calculated to be 0.0169412(11) uÅ2.

  13. Rapid authentication of different ages of tissue-cultured and wild Dendrobium huoshanense as well as wild Dendrobium henanense using FTIR and 2D-COS IR

    Science.gov (United States)

    Chen, Nai-Dong; Chen, Nai-Fu; Li, Jun; Cao, Cai-Yun; Wang, Jin-Mei

    2015-12-01

    The accumulating of pharmaceutical chemicals in medicinal plants would greatly be affected by their ages and establishing a fast quality-identification method to evaluate the similarity of medicinal herbs at different cultivated ages is a critical step for assurance of quality and safety in the TCM industry. In this work, tri-step IR macro-fingerprinting and 2D-COS IR spectrum techniques combined with statistical pattern recognition were applied for discrimination and similarity evaluation of different ages of tissue-cultured and wild Dendrobium huoshanense C. Z. Tang et S. J. Cheng as well as Dendrobium henanense J.L.Lu et L.X Gao. Both tissue-cultured and wild D. huoshanense were easily differentiated from D. henanense by FTIR and SD-IR spectra, while it's quite difficult to discriminate different cultivated years of the three investigated Dendrobiums. In 2D-COS IR spectra, 1-5 auto-peaks with different indensity and positions were located in the region 1160-1030 cm-1 of the twelve Dendrobium samples and thus could be used to identify Dendrobium samples at different ages. Principle component analysis (PCA) of synchronous 2D-COS data showed that the twelve samples were effectively identified and evaluated. The results indicated that the tri-step infrared macro-fingerprinting combined with PCA method was suitable to differentiate the cultivated ages of Dendrobiums with species and orgins rapidly and nondestructively.

  14. Properties of the Variation of the Infrared Emission of OH/IR Stars I. The K Band Light Curves

    Directory of Open Access Journals (Sweden)

    Kyung-Won Suh

    2009-09-01

    Full Text Available To study properties of the variation of the infrared emission of OH/IR stars, we collect and analyze the infrared observational data in K band for nine OH/IR stars. We use the observational data obtained for about three decades including recent data from the two micron all sky survey (2MASS and the deep near infrared survey of the southern sky (DENIS. We use Marquardt-Levenberg algorithm to determine the pulsation period and amplitude for each star and compare them with previous results of infrared and radio investigations.

  15. Fourier transform infrared spectroscopy of D212CO in the 2500-4500 cm-1 region and the first rovibrational analysis of its v2 = 2 state

    Science.gov (United States)

    A'dawiah, Rabia'tul; Tan, T. L.; Ng, L. L.

    2018-03-01

    A low-resolution (0.5 cm-1) Fourier transform infrared (FTIR) spectrum of formaldehyde-d2 (D212CO) in the 2500-4500 cm-1 region was recorded to study the combination bands in this region. The bands ν2 +ν4,ν2 +ν6 , ν2 +ν3 , ν1 +ν2 , ν2 +ν5 , 3ν3 , 2ν2 and 2ν5 were identified and their band centers (with an uncertainty of ± 0.1 cm-1) and band types were determined. Furthermore, the high-resolution FTIR spectrum of the 2ν2 overtone band (3315-3440 cm-1) of D212CO was recorded at an unapodized resolution of 0.0063 cm-1 and its infrared lines were analyzed. A total of 970 rovibrational transitions have been assigned and fitted up to J‧ = 35 and Ka‧ = 14 using the Watson's A-reduced Hamiltonian in the Ir representation. Upper state (v2 = 2) rovibrational constants inclusive of three rotational and five quartic centrifugal distortion constants were accurately determined for the first time. The band center of the 2ν2 band was determined as 3385.200666 ± 0.000035 cm-1. The rms deviation of the rovibrational fit was 0.00093 cm-1. From the fitting of 451 ground state combination differences (GSCDs) of D212CO which were derived from the infrared transitions of the 2ν2 band of this work, together with 360 microwave frequencies from a previous study, new and accurate ground state constants of D212CO up to three octic terms were obtained. The combination and overtone bands and the newly assigned high-resolution infrared lines of the 2ν2 band in the 2500-4500 cm-1 region can be used to detect D212CO in this infrared region. In addition, the results derived from this study give information on the rovibrational molecular structure of D212CO.

  16. 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.

  17. Glucose Induces Mouse β-Cell Proliferation via IRS2, MTOR, and Cyclin D2 but Not the Insulin Receptor

    Science.gov (United States)

    Stamateris, Rachel E.; Sharma, Rohit B.; Kong, Yahui; Ebrahimpour, Pantea; Panday, Deepika; Ranganath, Pavana; Zou, Baobo; Levitt, Helena; Parambil, Nisha Abraham; O’Donnell, Christopher P.; García-Ocaña, Adolfo

    2016-01-01

    An important goal in diabetes research is to understand the processes that trigger endogenous β-cell proliferation. Hyperglycemia induces β-cell replication, but the mechanism remains debated. A prime candidate is insulin, which acts locally through the insulin receptor. Having previously developed an in vivo mouse hyperglycemia model, we tested whether glucose induces β-cell proliferation through insulin signaling. By using mice lacking insulin signaling intermediate insulin receptor substrate 2 (IRS2), we confirmed that hyperglycemia-induced β-cell proliferation requires IRS2 both in vivo and ex vivo. Of note, insulin receptor activation was not required for glucose-induced proliferation, and insulin itself was not sufficient to drive replication. Glucose and insulin caused similar acute signaling in mouse islets, but chronic signaling differed markedly, with mammalian target of rapamycin (MTOR) and extracellular signal–related kinase (ERK) activation by glucose and AKT activation by insulin. MTOR but not ERK activation was required for glucose-induced proliferation. Cyclin D2 was necessary for glucose-induced β-cell proliferation. Cyclin D2 expression was reduced when either IRS2 or MTOR signaling was lost, and restoring cyclin D2 expression rescued the proliferation defect. Human islets shared many of these regulatory pathways. Taken together, these results support a model in which IRS2, MTOR, and cyclin D2, but not the insulin receptor, mediate glucose-induced proliferation. PMID:26740601

  18. 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.

  19. Design of visible and IR infrared dual-band common-path telescope system

    Science.gov (United States)

    Guo, YuLin; Yu, Xun; Tao, Yu; Jiang, Xu

    2018-01-01

    The use of visible and IR infrared dual-band combination can effectively improve the performance of photoelectric detection system,TV and IR system were designed with the common path by the common reflection optical system.A TV/IR infrared common-caliber and common-path system is designed,which can realize the Remote and all-day information.For the 640×512 cooled focal plane array,an infrared middle wave system was presented with a focal length of 600mm F number of 4 field of view(FOV) of 0.38°×0.43°, the system uses optical passive thermal design, has o compact structure and can meet 100% cold shield efficiency,meanwhile it meets the design requirements of lightweight and athermalization. For the 1920×1080 pixels CCD,a visible (TV) system ,which had 500mm focal length, 4F number,was completed.The final optical design along with their modulation transfer function is presented,showing excellent imaging performance in dual-band at the temperature range between -40° and 60°.

  20. Spin orientations of the spin-half Ir(4+) ions in Sr3NiIrO6, Sr2IrO4, and Na2IrO3: Density functional, perturbation theory, and Madelung potential analyses.

    Science.gov (United States)

    Gordon, Elijah E; Xiang, Hongjun; Köhler, Jürgen; Whangbo, Myung-Hwan

    2016-03-21

    The spins of the low-spin Ir(4+) (S = 1/2, d(5)) ions at the octahedral sites of the oxides Sr3NiIrO6, Sr2IrO4, and Na2IrO3 exhibit preferred orientations with respect to their IrO6 octahedra. We evaluated the magnetic anisotropies of these S = 1/2 ions on the basis of density functional theory (DFT) calculations including spin-orbit coupling (SOC), and probed their origin by performing perturbation theory analyses with SOC as perturbation within the LS coupling scheme. The observed spin orientations of Sr3NiIrO6 and Sr2IrO4 are correctly predicted by DFT calculations, and are accounted for by the perturbation theory analysis. As for the spin orientation of Na2IrO3, both experimental studies and DFT calculations have not been unequivocal. Our analysis reveals that the Ir(4+) spin orientation of Na2IrO3 should have nonzero components along the c- and a-axis directions. The spin orientations determined by DFT calculations are sensitive to the accuracy of the crystal structures employed, which is explained by perturbation theory analyses when interactions between adjacent Ir(4+) ions are taken into consideration. There are indications implying that the 5d electrons of Na2IrO3 are less strongly localized compared with those of Sr3NiIrO6 and Sr2IrO4. This implication was confirmed by showing that the Madelung potentials of the Ir(4+) ions are less negative in Na2IrO3 than in Sr3NiIrO6 and Sr2IrO4. Most transition-metal S = 1/2 ions do have magnetic anisotropies because the SOC induces interactions among their crystal-field split d-states, and the associated mixing of the states modifies only the orbital parts of the states. This finding cannot be mimicked by a spin Hamiltonian because this model Hamiltonian lacks the orbital degree of freedom, thereby leading to the spin-half syndrome. The spin-orbital entanglement for the 5d spin-half ions Ir(4+) is not as strong as has been assumed.

  1. Currency verification by a 2D infrared barcode

    International Nuclear Information System (INIS)

    Schirripa Spagnolo, Giuseppe; Cozzella, Lorenzo; Simonetti, Carla

    2010-01-01

    Nowadays all the National Central Banks are continuously studying innovative anti-counterfeiting systems for banknotes. In this note, an innovative solution is proposed, which combines the potentiality of a hylemetric approach (methodology conceptually similar to biometry), based on notes' intrinsic characteristics, with a well-known and consolidated 2D barcode identification system. In particular, in this note we propose to extract from the banknotes a univocal binary control sequence (template) and insert an encrypted version of it in a barcode printed on the same banknote. For a more acceptable look and feel of a banknote, the superposed barcode can be stamped using IR ink that is visible to near-IR image sensors. This makes the banknote verification simpler. (technical design note)

  2. High-definition Fourier Transform Infrared (FT-IR) Spectroscopic Imaging of Human Tissue Sections towards Improving Pathology

    Science.gov (United States)

    Nguyen, Peter L.; Davidson, Bennett; Akkina, Sanjeev; Guzman, Grace; Setty, Suman; Kajdacsy-Balla, Andre; Walsh, Michael J.

    2015-01-01

    High-definition Fourier Transform Infrared (FT-IR) spectroscopic imaging is an emerging approach to obtain detailed images that have associated biochemical information. FT-IR imaging of tissue is based on the principle that different regions of the mid-infrared are absorbed by different chemical bonds (e.g., C=O, C-H, N-H) within cells or tissue that can then be related to the presence and composition of biomolecules (e.g., lipids, DNA, glycogen, protein, collagen). In an FT-IR image, every pixel within the image comprises an entire Infrared (IR) spectrum that can give information on the biochemical status of the cells that can then be exploited for cell-type or disease-type classification. In this paper, we show: how to obtain IR images from human tissues using an FT-IR system, how to modify existing instrumentation to allow for high-definition imaging capabilities, and how to visualize FT-IR images. We then present some applications of FT-IR for pathology using the liver and kidney as examples. FT-IR imaging holds exciting applications in providing a novel route to obtain biochemical information from cells and tissue in an entirely label-free non-perturbing route towards giving new insight into biomolecular changes as part of disease processes. Additionally, this biochemical information can potentially allow for objective and automated analysis of certain aspects of disease diagnosis. PMID:25650759

  3. [Infrared spectroscopic analysis of Guilin watermelon frost products].

    Science.gov (United States)

    Huang, Dong-lan; Chen, Xiao-kang; Xu, Yong-qun; Sun, Su-qin; Zhou, Qun; Lu, Wen-guan

    2012-08-01

    The objective of the present study is to analyze different products of Guilin watermelon frost by Fourier transform infrared spectroscopy (FTIR), second derivative infrared spectroscopy and two-dimensional correlation spectroscopy (2D-IR) under thermal perturbation. The structural information of the samples indicates that samples from the same factory but of different brands had some dissimilarities in the IR spectra, and the type and content of accessories of them were different compared with conventional IR spectra of samples, peaks at 638 and 616 cm(-1) all arise from anhydrous sodium sulfate in watermelon frost spray and watermelon frost capsule; the characteristic absorption peaks of the sucrose, dextrin or other accessories can be seen clearly in the spectra of watermelon frost throat-clearing buccal tablets, watermelon frost throat tablets and watermelon frost lozenge. And the IR spectra of watermelon frost lozenge is very similar to the IR spectra of sucrose, so it can be easily proved that the content of sucrose in watermelon frost lozenge is high. In the 2D-IR correlation spectra, the samples presented the differences in the position, number and relative intensity of autopeaks and correlation peak clusters. Consequently, the macroscopical fingerprint characters of FTIR, second derivative infrared spectra and 2D-IR spectra can not only provide the information about main chemical constituents in medical materials, but also analyze and identify the type and content of accessories in Guilin watermelon frost. In conclusion, the multi-steps IR macro-fingerprint method is rapid, effective, visual and accurate for pharmaceutical research.

  4. INFRARED ABSORPTION LINES TOWARD NGC 7538 IRS 1: ABUNDANCES OF H{sub 2}, H{sub 3}{sup +}, AND CO

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Miwa [Universitäts-Sternwarte München, Scheinerstr. 1, D-81679 Munich (Germany); Geballe, T. R. [Gemini Observatory, 670 North A‘ohoku Place, Hilo, HI 96720 (United States); Usuda, Tomonori, E-mail: mgoto@usm.lmu.de, E-mail: tgeballe@gemini.edu, E-mail: usuda@naoj.org [Subaru Telescope, 650 North A‘ohoku Place, Hilo, HI 96720 (United States)

    2015-06-10

    We report high-resolution near-infrared absorption spectroscopy of H{sub 2}, H{sub 3}{sup +}, and CO toward the young high mass object NGC 7538 IRS 1. The v = 1–0 H{sub 2} S(0) line and lines in the CO v = 2–0 band were detected; the v = 1–0 H{sub 2} S(1) line and the v = 1–0 H{sub 3}{sup +} lines [R(1, 1){sup l}, R(1, 0), R(1, 1){sup u}] were not detected. The line of sight traverses two clouds, with temperatures 45 and 259 K and with roughly equal column densities of CO. Assuming that H{sub 2} is at the same temperature as CO and that the two species are uniformly mixed, [H{sub 2}]/[CO] = 3600 ± 1200. NGC 7538 is the most distant object from the Galactic center for which [H{sub 2}]/[CO] has been directly measured using infrared absorption spectroscopy.

  5. Chemical fingerprinting of Arabidopsis using Fourier transform infrared (FT-IR) spectroscopic approaches.

    Science.gov (United States)

    Gorzsás, András; Sundberg, Björn

    2014-01-01

    Fourier transform infrared (FT-IR) spectroscopy is a fast, sensitive, inexpensive, and nondestructive technique for chemical profiling of plant materials. In this chapter we discuss the instrumental setup, the basic principles of analysis, and the possibilities for and limitations of obtaining qualitative and semiquantitative information by FT-IR spectroscopy. We provide detailed protocols for four fully customizable techniques: (1) Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS): a sensitive and high-throughput technique for powders; (2) attenuated total reflectance (ATR) spectroscopy: a technique that requires no sample preparation and can be used for solid samples as well as for cell cultures; (3) microspectroscopy using a single element (SE) detector: a technique used for analyzing sections at low spatial resolution; and (4) microspectroscopy using a focal plane array (FPA) detector: a technique for rapid chemical profiling of plant sections at cellular resolution. Sample preparation, measurement, and data analysis steps are listed for each of the techniques to help the user collect the best quality spectra and prepare them for subsequent multivariate analysis.

  6. 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.

  7. Ultrafast vibrational spectroscopy (2D-IR) of CO{sub 2} in ionic liquids: Carbon capture from carbon dioxide’s point of view

    Energy Technology Data Exchange (ETDEWEB)

    Brinzer, Thomas; Berquist, Eric J.; Ren, Zhe; Dutta, Samrat; Johnson, Clinton A.; Krisher, Cullen S.; Lambrecht, Daniel S.; Garrett-Roe, Sean, E-mail: sgr@pitt.edu [Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260 (United States)

    2015-06-07

    The CO{sub 2}ν{sub 3} asymmetric stretching mode is established as a vibrational chromophore for ultrafast two-dimensional infrared (2D-IR) spectroscopic studies of local structure and dynamics in ionic liquids, which are of interest for carbon capture applications. CO{sub 2} is dissolved in a series of 1-butyl-3-methylimidazolium-based ionic liquids ([C{sub 4}C{sub 1}im][X], where [X]{sup −} is the anion from the series hexafluorophosphate (PF{sub 6}{sup −}), tetrafluoroborate (BF{sub 4}{sup −}), bis-(trifluoromethyl)sulfonylimide (Tf{sub 2}N{sup −}), triflate (TfO{sup −}), trifluoroacetate (TFA{sup −}), dicyanamide (DCA{sup −}), and thiocyanate (SCN{sup −})). In the ionic liquids studied, the ν{sub 3} center frequency is sensitive to the local solvation environment and reports on the timescales for local structural relaxation. Density functional theory calculations predict charge transfer from the anion to the CO{sub 2} and from CO{sub 2} to the cation. The charge transfer drives geometrical distortion of CO{sub 2}, which in turn changes the ν{sub 3} frequency. The observed structural relaxation timescales vary by up to an order of magnitude between ionic liquids. Shoulders in the 2D-IR spectra arise from anharmonic coupling of the ν{sub 2} and ν{sub 3} normal modes of CO{sub 2}. Thermal fluctuations in the ν{sub 2} population stochastically modulate the ν{sub 3} frequency and generate dynamic cross-peaks. These timescales are attributed to the breakup of ion cages that create a well-defined local environment for CO{sub 2}. The results suggest that the picosecond dynamics of CO{sub 2} are gated by local diffusion of anions and cations.

  8. 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)

  9. β-Isocyanoalanine as an IR probe: comparison of vibrational dynamics between isonitrile and nitrile-derivatized IR probes.

    Science.gov (United States)

    Maj, Michał; Ahn, Changwoo; Kossowska, Dorota; Park, Kwanghee; Kwak, Kyungwon; Han, Hogyu; Cho, Minhaeng

    2015-05-07

    An infrared (IR) probe based on isonitrile (NC)-derivatized alanine 1 was synthesized and the vibrational properties of its NC stretching mode were investigated using FTIR and femtosecond IR pump-probe spectroscopy. It is found that the NC stretching mode is very sensitive to the hydrogen-bonding ability of solvent molecules. Moreover, its transition dipole strength is larger than that of nitrile (CN) in nitrile-derivatized IR probe 2. The vibrational lifetime of the NC stretching mode is found to be 5.5 ± 0.2 ps in both D2O and DMF solvents, which is several times longer than that of the azido (N3) stretching mode in azido-derivatized IR probe 3. Altogether these properties suggest that the NC group can be a very promising sensing moiety of IR probes for studying the solvation structure and dynamics of biomolecules.

  10. Far-IR transparency and dynamic infrared signature control with novel conducting polymer systems

    Science.gov (United States)

    Chandrasekhar, Prasanna; Dooley, T. J.

    1995-09-01

    Materials which possess transparency, coupled with active controllability of this transparency in the infrared (IR), are today an increasingly important requirement, for varied applications. These applications include windows for IR sensors, IR-region flat panel displays used in camouflage as well as in communication and sight through night-vision goggles, coatings with dynamically controllable IR-emissivity, and thermal conservation coatings. Among stringent requirements for these applications are large dynamic ranges (color contrast), 'multi-color' or broad-band characteristics, extended cyclability, long memory retention, matrix addressability, small area fabricability, low power consumption, and environmental stability. Among materials possessing the requirements for variation of IR signature, conducting polymers (CPs) appear to be the only materials with dynamic, actively controllable signature and acceptable dynamic range. Conventional CPs such as poly(alkyl thiophene), poly(pyrrole) or poly(aniline) show very limited dynamic range, especially in the far-IR, while also showing poor transparency. We have developed a number of novel CP systems ('system' implying the CP, the selected dopant, the synthesis method, and the electrolyte) with very wide dynamic range (up to 90% in both important IR regions, 3 - 5 (mu) and 8 - 12 (mu) ), high cyclability (to 105 cycles with less than 10% optical degradation), nearly indefinite optical memory retention, matrix addressability of multi-pixel displays, very wide operating temperature and excellent environmental stability, low charge capacity, and processability into areas from less than 1 mm2 to more than 100 cm2. The criteria used to design and arrive at these CP systems, together with representative IR signature data, are presented in this paper.

  11. 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.

  12. Enhancing signal detection and completely eliminating scattering using quasi-phase-cycling in 2D IR experiments.

    Science.gov (United States)

    Bloem, Robbert; Garrett-Roe, Sean; Strzalka, Halina; Hamm, Peter; Donaldson, Paul

    2010-12-20

    We demonstrate how quasi-phase-cycling achieved by sub-cycle delay modulation can be used to replace optical chopping in a box-CARS 2D IR experiment in order to enhance the signal size, and, at the same time, completely eliminate any scattering contamination. Two optical devices are described that can be used for this purpose, a wobbling Brewster window and a photoelastic modulator. They are simple to construct, easy to incorporate into any existing 2D IR setup, and have attractive features such as a high optical throughput and a fast modulation frequency needed to phase cycle on a shot-to-shot basis.

  13. 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.

  14. Narrowband infrared emitters for combat ID

    Science.gov (United States)

    Pralle, Martin U.; Puscasu, Irina; Daly, James; Fallon, Keith; Loges, Peter; Greenwald, Anton; Johnson, Edward

    2007-04-01

    There is a strong desire to create narrowband infrared light sources as personnel beacons for application in infrared Identify Friend or Foe (IFF) systems. This demand has augmented dramatically in recent years with the reports of friendly fire casualties in Afghanistan and Iraq. ICx Photonics' photonic crystal enhanced TM (PCE TM) infrared emitter technology affords the possibility of creating narrowband IR light sources tuned to specific IR wavebands (near 1-2 microns, mid 3-5 microns, and long 8-12 microns) making it the ideal solution for infrared IFF. This technology is based on a metal coated 2D photonic crystal of air holes in a silicon substrate. Upon thermal excitation the photonic crystal modifies the emitted yielding narrowband IR light with center wavelength commensurate with the periodicity of the lattice. We have integrated this technology with microhotplate MEMS devices to yield 15mW IR light sources in the 3-5 micron waveband with wall plug efficiencies in excess of 10%, 2 orders of magnitude more efficient that conventional IR LEDs. We have further extended this technology into the LWIR with a light source that produces 9 mW of 8-12 micron light at an efficiency of 8%. Viewing distances >500 meters were observed with fielded camera technologies, ideal for ground to ground troop identification. When grouped into an emitter panel, the viewing distances were extended to 5 miles, ideal for ground to air identification.

  15. Submillisecond mixing in a continuous-flow, microfluidic mixer utilizing mid-infrared hyperspectral imaging detection.

    Science.gov (United States)

    Kise, Drew P; Magana, Donny; Reddish, Michael J; Dyer, R Brian

    2014-02-07

    We report a continuous-flow, microfluidic mixer utilizing mid-infrared hyperspectral imaging detection, with an experimentally determined, submillisecond mixing time. The simple and robust mixer design has the microfluidic channels cut through a polymer spacer that is sandwiched between two IR transparent windows. The mixer hydrodynamically focuses the sample stream with two side flow channels, squeezing it into a thin jet and initiating mixing through diffusion and advection. The detection system generates a mid-infrared hyperspectral absorbance image of the microfluidic sample stream. Calibration of the hyperspectral image yields the mid-IR absorbance spectrum of the sample versus time. A mixing time of 269 μs was measured for a pD jump from 3.2 to above 4.5 in a D2O sample solution of adenosine monophosphate (AMP), which acts as an infrared pD indicator. The mixer was further characterized by comparing experimental results with a simulation of the mixing of an H2O sample stream with a D2O sheath flow, showing good agreement between the two. The IR microfluidic mixer eliminates the need for fluorescence labeling of proteins with bulky, interfering dyes, because it uses the intrinsic IR absorbance of the molecules of interest, and the structural specificity of IR spectroscopy to follow specific chemical changes such as the protonation state of AMP.

  16. Identification of Serine Conformers by Matrix-Isolation IR Spectroscopy Aided by Near-Infrared Laser-Induced Conformational Change, 2D Correlation Analysis, and Quantum Mechanical Anharmonic Computations.

    Science.gov (United States)

    Najbauer, Eszter E; Bazsó, Gábor; Apóstolo, Rui; Fausto, Rui; Biczysko, Malgorzata; Barone, Vincenzo; Tarczay, György

    2015-08-20

    The conformers of α-serine were investigated by matrix-isolation IR spectroscopy combined with NIR laser irradiation. This method, aided by 2D correlation analysis, enabled unambiguously grouping the spectral lines to individual conformers. On the basis of comparison of at least nine experimentally observed vibrational transitions of each conformer with empirically scaled (SQM) and anharmonic (GVPT2) computed IR spectra, six conformers were identified. In addition, the presence of at least one more conformer in Ar matrix was proved, and a short-lived conformer with a half-life of (3.7 ± 0.5) × 10(3) s in N2 matrix was generated by NIR irradiation. The analysis of the NIR laser-induced conversions revealed that the excitation of the stretching overtone of both the side chain and the carboxylic OH groups can effectively promote conformational changes, but remarkably different paths were observed for the two kinds of excitations.

  17. Relationship between HOMA-IR and serum vitamin D in Chinese children and adolescents.

    Science.gov (United States)

    Wang, Lingli; Wang, Huiyan; Wen, Huaikai; Tao, Hongqun; Zhao, Xiaowei

    2016-07-01

    The objective of this study was to examine the cross-sectional relationship between homeostasis model assessment for insulin resistance (HOMA-IR) and serum 25-hydroxyvitamin D (25-OHD) level in Chinese children and adolescents. Anthropometric indices, lipid metabolic profile, and serum levels of glucose, insulin and 25-OHD were determined among 278 healthy prepubertal and pubertal, normal and overweight/obese children and adolescents aged 8-18 years between March 2014 and February 2015. HOMA-IR was significantly different across vitamin D statuses (pHOMA-IR negatively correlated with serum 25-OHD level for all subjects (R2=0.148, pHOMA-IR and BMI and serum 25-OHD level (R2=0.654, pHOMA-IR. Our findings supported that lower vitamin D status is strongly associated with worse HOMA-IR.

  18. Assessment of Azithromycin in Pharmaceutical Formulation by Fourier-transform Infrared (FT-IR Transmission Spectroscopy

    Directory of Open Access Journals (Sweden)

    Muhammad Ali Mallah

    2011-12-01

    Full Text Available A simple, rapid and economical method for azithromycin quantification in solid tablet and capsule formulations has been developed by applying Fourier-transform Infrared (FT-IR transmission spectroscopy for regular quality monitoring. The newly developed method avoids the sample preparation, except grinding for pellet formation and does not involve consumption of any solvent as it absolutely eliminates the need of extraction. KBr pellets were employed for the appraisal of azithromycin while acquiring spectra of standards as well as samples on FT-IR. By selecting the FT-IR carbonyl band (C=O in the region 1,744–1,709 cm−1 the calibration model was developed based on simple Beer’s law. The excellent regression coefficient (R2 0.999 was accomplished for calibration set having standard error of calibration equal to 0.01 mg. The current work exposes that transmission FT-IR spectroscopy can definitely be applied to determine the exact amount of azithromycin to control the processing and quality of solid formulations with reduced cost and short analysis time.

  19. Infrared realization of dS2 in AdS2

    Science.gov (United States)

    Anninos, Dionysios; Hofman, Diego M.

    2018-04-01

    We describe a two-dimensional geometry that smoothly interpolates between an asymptotically AdS2 geometry and the static patch of dS2. We find this ‘centaur’ geometry to be a solution of dilaton gravity with a specific class of potentials for the dilaton. We interpret the centaur geometry as a thermal state in the putative quantum mechanics dual to the AdS2 evolved with the global Hamiltonian. We compute the thermodynamic properties and observe that the centaur state has finite entropy and positive specific heat. The static patch is the infrared part of the centaur geometry. We discuss boundary observables sensitive to the static patch region.

  20. Infrared

    Science.gov (United States)

    Vollmer, M.

    2013-11-01

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

  1. Identification of Serine Conformers by Matrix-Isolation IR Spectroscopy Aided by Near-Infrared Laser Induced Conformational Change, 2D Correlation Analysis, and Quantum Mechanical Anharmonic Computations

    Science.gov (United States)

    Najbauer, Eszter E.; Bazsó, Gábor; Apóstolo, Rui; Fausto, Rui; Biczysko, Malgorzata; Barone, Vincenzo; Tarczay, György

    2018-01-01

    The conformers of α-serine were investigated by matrix-isolation IR spectroscopy combined with NIR laser irradiation. This method, aided by 2D correlation analysis, enabled unambiguously grouping the spectral lines to individual conformers. On the basis of comparison of at least nine experimentally observed vibrational transitions of each conformer with empirically scaled (SQM) and anharmonic (GVPT2) computed IR spectra, 6 conformers were identified. In addition, the presence of at least one more conformer in Ar matrix was proved, and a short-lived conformer with a half-live of (3.7±0.5)·103 s in N2 matrix was generated by NIR irradiation. The analysis of the NIR laser induced conversions revealed that the excitation of the stretching overtone of both the side-chain and the carboxylic OH groups can effectively promote conformational changes, but remarkably different paths were observed for the two kinds of excitations. PMID:26201050

  2. Structure, magnetism and electronic properties in 3d-5d based double perovskite (Sr1-xYx)2FeIrO6.

    Science.gov (United States)

    Kharkwal, Kishor Chandra; Pramanik, Ashim Kumar

    2017-10-17

    The 3$d$-5$d$ based double perovskites are of current interest as they provide model system to study the interplay between electronic correlation ($U$) and spin-orbit coupling (SOC). Here we report detailed structural, magnetic and transport properties of doped double perovskite material (Sr$_{1-x}$Y$_x$)$_2$FeIrO$_6$ with $x$ $\\leq$ 0.2. With substitution of Y, system retains its original crystal structure but structural parameters modify with $x$ in nonmonotonic fashion. The magnetization data for Sr$_2$FeIrO$_6$ show antiferromagnetic type magnetic transition around 45 K, however, a close inspection in data indicates a weak magnetic phase transition around 120 K. No change of structural symmetry has been observed down to low temperature, although the lattice parameters show sudden changes around the magnetic transitions. Sr$_2$FeIrO$_6$ shows an insulating behavior over the whole temperature range which yet does not change with Y substitution. Nature of charge conduction is found to follow thermally activated Mott's variable range hopping and power law behavior for parent and doped samples, respectively. Interestingly, evolution of structural, magnetic and transport behavior in (Sr$_{1-x}$Y$_x$)$_2$FeIrO$_6$ is observed to reverse with $x$ $>$ 0.1 which is believed to arise due to change in transition metal ionic state. © 2017 IOP Publishing Ltd.

  3. Characterization of a novel miniaturized burst-mode infrared laser system for IR-MALDESI mass spectrometry imaging.

    Science.gov (United States)

    Ekelöf, Måns; Manni, Jeffrey; Nazari, Milad; Bokhart, Mark; Muddiman, David C

    2018-03-01

    Laser systems are widely used in mass spectrometry as sample probes and ionization sources. Mid-infrared lasers are particularly suitable for analysis of high water content samples such as animal and plant tissues, using water as a resonantly excited sacrificial matrix. Commercially available mid-IR lasers have historically been bulky and expensive due to cooling requirements. This work presents a novel air-cooled miniature mid-IR laser with adjustable burst-mode output and details an evaluation of its performance for mass spectrometry imaging. The miniature laser was found capable of generating sufficient energy for complete ablation of animal tissue in the context of an IR-MALDESI experiment with exogenously added ice matrix, yielding several hundred confident metabolite identifications. Graphical abstract The use of a novel miniature 2.94 μm burst-mode laser in IR-MALDESI allows for rapid and sensitive mass spectrometry imaging of a whole mouse.

  4. Rapid identification of Chinese Sauce liquor from different fermentation positions with FT-IR spectroscopy

    Science.gov (United States)

    Li, Changwen; Wei, Jiping; Zhou, Qun; Sun, Suqin

    2008-07-01

    FT-IR and two-dimensional correlation spectroscopy (2D-IR) technology were applied to discriminate Chinese Sauce liquor from different fermentation positions (top, middle and bottom of fermentation cellar) for the first time. The liquors at top, middle and bottom of fermentation cellar, possessed the characteristic peaks at 1731 cm -1, 1733 cm -1 and 1602 cm -1, respectively. In the 2D correlation infrared spectra, the differences were amplified. A strong auto-peak at 1725 cm -1 showed in the 2D spectra of the Top Liquor, which indicated that the liquor might contain some ester compounds. Different from Top Liquor, three auto-peaks at 1695, 1590 and 1480 cm -1 were identified in 2D spectra of Middle Liquor, which were the characteristic absorption of acid, lactate. In 2D spectra of Bottom Liquor, two auto-peaks at 1570 and 1485 cm -1 indicated that lactate was the major component. As a result, FT-IR and 2D-IR correlation spectra technology provided a rapid and effective method for the quality analysis of the Sauce liquor.

  5. 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.

  6. 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

  7. Application of Fourier transform infrared (FT-IR) spectroscopy in determination of microalgal compositions.

    Science.gov (United States)

    Meng, Yingying; Yao, Changhong; Xue, Song; Yang, Haibo

    2014-01-01

    Fourier transform infrared spectroscopy (FT-IR) was applied in algal strain screening and monitoring cell composition dynamics in a marine microalga Isochrysis zhangjiangensis during algal cultivation. The content of lipid, carbohydrate and protein of samples determined by traditional methods had validated the accuracy of FT-IR method. For algal screening, the band absorption ratios of lipid/amide I and carbo/amide I from FT-IR measurements allowed for the selection of Isochrysis sp. and Tetraselmis subcordiformis as the most potential lipid and carbohydrate producers, respectively. The cell composition dynamics of I. zhangjiangensis measured by FT-IR revealed the diversion of carbon allocation from protein to carbohydrate and neutral lipid when nitrogen-replete cells were subjected to nitrogen limitation. The carbo/amide I band absorption ratio had also been demonstrated to depict physiological status under nutrient stress in T. subcordiformis. FT-IR serves as a tool for the simultaneous measurement of lipid, carbohydrate, and protein content in cell. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Infrared behaviour of massless QED in space-time dimensions 2<d<4

    International Nuclear Information System (INIS)

    Mitra, Indrajit; Ratabole, Raghunath; Sharatchandra, H.S.

    2005-01-01

    We show that the logarithmic infrared divergences in electron self-energy and vertex function of massless QED in 2+1 dimensions can be removed at all orders of 1/N by an appropriate choice of a non-local gauge. Thus the infrared behaviour given by the leading order in 1/N is not modified by higher order corrections. Our analysis gives a computational scheme for the Amati-Testa model, resulting in a non-trivial conformal invariant field theory for all space-time dimensions 2< d<4

  9. Infrared behaviour of massless QED in space-time dimensions 2<d<4

    Energy Technology Data Exchange (ETDEWEB)

    Mitra, Indrajit [The Institute of Mathematical Sciences, C.I.T. Campus, Taramani P.O., Chennai 600113 (India) and Theory Group, Saha Institute of Nuclear Physics, 1/AF Bidhan-Nagar, Kolkata 700064 (India)]. E-mail: indra@theory.saha.ernet.in; Ratabole, Raghunath [The Institute of Mathematical Sciences, C.I.T. Campus, Taramani P.O., Chennai 600113 (India)]. E-mail: raghu@imsc.res.in; Sharatchandra, H.S. [The Institute of Mathematical Sciences, C.I.T. Campus, Taramani P.O., Chennai 600113 (India)]. E-mail: sharat@imsc.res.in

    2005-04-07

    We show that the logarithmic infrared divergences in electron self-energy and vertex function of massless QED in 2+1 dimensions can be removed at all orders of 1/N by an appropriate choice of a non-local gauge. Thus the infrared behaviour given by the leading order in 1/N is not modified by higher order corrections. Our analysis gives a computational scheme for the Amati-Testa model, resulting in a non-trivial conformal invariant field theory for all space-time dimensions 2<d<4.

  10. Infrared reflection nebulae in Orion Molecular Cloud

    International Nuclear Information System (INIS)

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

    1986-01-01

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

  11. TECHNICAL DESIGN NOTE: Currency verification by a 2D infrared barcode

    Science.gov (United States)

    Schirripa Spagnolo, Giuseppe; Cozzella, Lorenzo; Simonetti, Carla

    2010-10-01

    Nowadays all the National Central Banks are continuously studying innovative anti-counterfeiting systems for banknotes. In this note, an innovative solution is proposed, which combines the potentiality of a hylemetric approach (methodology conceptually similar to biometry), based on notes' intrinsic characteristics, with a well-known and consolidated 2D barcode identification system. In particular, in this note we propose to extract from the banknotes a univocal binary control sequence (template) and insert an encrypted version of it in a barcode printed on the same banknote. For a more acceptable look and feel of a banknote, the superposed barcode can be stamped using IR ink that is visible to near-IR image sensors. This makes the banknote verification simpler.

  12. Structure, magnetism and electronic properties in 3d-5d based double perovskite ({Sr_{1-x}} Y x )2FeIrO6

    Science.gov (United States)

    Kharkwal, K. C.; Pramanik, A. K.

    2017-12-01

    The 3d-5d based double perovskites are of current interest as they provide model systems to study the interplay between electronic correlation (U) and spin-orbit coupling (SOC). Here, we report detailed structural, magnetic and transport properties of doped double perovskite material (Sr1-x Y x )2FeIrO6 with x ≤slant 0.2 . With substitution of Y, the system retains its original crystal structure but structural parameters change with x in nonmonotonic fashion. The magnetization data for Sr2FeIrO6 show antiferromagnetic type magnetic transition around 45 K however, a close inspection of the data indicates a weak magnetic phase transition around 120 K. No change of structural symmetry has been observed down to low temperature, although the lattice parameters show sudden changes around the magnetic transitions. Sr2FeIrO6 shows an insulating behavior over the whole temperature range, which nevertheless does not change with Y substitution. The nature of charge conduction is found to follow thermally activated Mott’s variable range hopping and power law behavior for parent and doped samples, respectively. Interestingly, evolution of structural, magnetic and transport behavior in (Sr1-x Y x )2FeIrO6 is observed to reverse with x > 0.1 , which is believed to arise due to a change in the transition metal ionic state.

  13. Wide-angle ITER-prototype tangential infrared and visible viewing system for DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Lasnier, C. J., E-mail: lasnier@LLNL.gov; Allen, S. L.; Ellis, R. E.; Fenstermacher, M. E.; McLean, A. G.; Meyer, W. H.; Morris, K.; Seppala, L. G. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States); Crabtree, K. [College of Optics, University of Arizona, Tucson, Arizona 85721 (United States); Van Zeeland, M. A. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)

    2014-11-15

    An imaging system with a wide-angle tangential view of the full poloidal cross-section of the tokamak in simultaneous infrared and visible light has been installed on DIII-D. The optical train includes three polished stainless steel mirrors in vacuum, which view the tokamak through an aperture in the first mirror, similar to the design concept proposed for ITER. A dichroic beam splitter outside the vacuum separates visible and infrared (IR) light. Spatial calibration is accomplished by warping a CAD-rendered image to align with landmarks in a data image. The IR camera provides scrape-off layer heat flux profile deposition features in diverted and inner-wall-limited plasmas, such as heat flux reduction in pumped radiative divertor shots. Demonstration of the system to date includes observation of fast-ion losses to the outer wall during neutral beam injection, and shows reduced peak wall heat loading with disruption mitigation by injection of a massive gas puff.

  14. The TApIR experiment. IR absorption spectra of liquid hydrogen isotopologues; Das TApIR Experiment IR-Absorptionsspektren fluessiger Wasserstoffisotopologe

    Energy Technology Data Exchange (ETDEWEB)

    Groessle, Robin

    2015-11-27

    The scope of the thesis is the infrared absorption spectroscopy of liquid hydrogen isotopologues with the tritium absorption infrared spectroscopy (TApIR) experiment at the tritium laboratory Karlsruhe (TLK). The calibration process from the sample preparation to the reference measurements are described. A further issue is the classical evaluation of FTIR absorption spectra and the extension using the rolling circle filter (RCF) including the effects on statistical and systematical errors. The impact of thermal and nuclear spin temperature on the IR absorption spectra is discussed. An empirical based modeling for the IR absorption spectra of liquid hydrogen isotopologues is performed.

  15. Investigation of conspicuous infrared star cluster and star-forming region RCW 38 IR Cluster

    International Nuclear Information System (INIS)

    Gyulbudaghian, A.L.; May, J.

    2008-01-01

    An infrared star cluster RCW 38 IR Cluster, which is also a massive star-forming region, is investigated. The results of observations with SEST (Cerro is Silla, Chile) telescope on 2.6-mm 12 CO spectral line and with SIMBA on 1.2-mm continuum are given. The 12 CO observations revealed the existence of several molecular clouds, two of which (clouds I and 2) are connected with the object RCW 38 IR Cluster. Cloud 1 is a massive cloud, which has a depression in which the investigated object is embedded. It is not excluded that the depression was formed by the wind and/or emission from the young bright stars belonging to the star cluster. Rotation of cloud 2, around the axis having SE-NW direction, with an angular velocity ω 4.6 · 10 -14 s -1 is also found. A red-shifted outflow with velocity ∼+5.6 km/s, in the SE direction and perpendicular to the elongation of cloud 2 has been also found. The investigated cluster is associated with an IR point source IRAS 08573-4718, which has IR colours typical for a, non-evolved embedded (in the cloud) stellar object. The cluster is also connected with a water maser. The SIMBA image shoves the existence of a central bright condensation, coinciding with the cluster itself, and two extensions. One of these extensions (the one with SW-NE direction) coincides, both in place and shape, with cloud 2, so that it is not excluded the possibility that this extension might be also rotating like cloud 2. In the vicinity of these extensions there are condensations resembling HH objects

  16. Mid-infrared multi-wavelength imaging of Ophiuchus IRS 48 transitional disk†

    Science.gov (United States)

    Honda, Mitsuhiko; Okada, Kazushi; Miyata, Takashi; Mulders, Gijs D.; Swearingen, Jeremy R.; Kamizuka, Takashi; Ohsawa, Ryou; Fujiyoshi, Takuya; Fujiwara, Hideaki; Uchiyama, Mizuho; Yamashita, Takuya; Onaka, Takashi

    2018-04-01

    Transitional disks around the Herbig Ae/Be stars are fascinating targets in the contexts of disk evolution and planet formation. Oph IRS 48 is one of such Herbig Ae stars, which shows an inner dust cavity and azimuthally lopsided large dust distribution. We present new images of Oph IRS 48 at eight mid-infrared (MIR) wavelengths from 8.59 to 24.6 μm taken with COMICS mounted on the 8.2 m Subaru Telescope. The N-band (7 to 13 μm) images show that the flux distribution is centrally peaked with a slight spatial extent, while the Q-band (17 to 25 μm) images show asymmetric double peaks (east and west). Using 18.8- and 24.6 μm images, we derived the dust temperature at both east and west peaks to be 135 ± 22 K. Thus, the asymmetry may not be attributed to a difference in the temperature. Comparing our results with previous modeling works, we conclude that the inner disk is aligned to the outer disk. A shadow cast by the optically thick inner disk has a great influence on the morphology of MIR thermal emission from the outer disk.

  17. Mid-infrared multi-wavelength imaging of Ophiuchus IRS 48 transitional disk†

    Science.gov (United States)

    Honda, Mitsuhiko; Okada, Kazushi; Miyata, Takashi; Mulders, Gijs D.; Swearingen, Jeremy R.; Kamizuka, Takashi; Ohsawa, Ryou; Fujiyoshi, Takuya; Fujiwara, Hideaki; Uchiyama, Mizuho; Yamashita, Takuya; Onaka, Takashi

    2018-06-01

    Transitional disks around the Herbig Ae/Be stars are fascinating targets in the contexts of disk evolution and planet formation. Oph IRS 48 is one of such Herbig Ae stars, which shows an inner dust cavity and azimuthally lopsided large dust distribution. We present new images of Oph IRS 48 at eight mid-infrared (MIR) wavelengths from 8.59 to 24.6 μm taken with COMICS mounted on the 8.2 m Subaru Telescope. The N-band (7 to 13 μm) images show that the flux distribution is centrally peaked with a slight spatial extent, while the Q-band (17 to 25 μm) images show asymmetric double peaks (east and west). Using 18.8- and 24.6 μm images, we derived the dust temperature at both east and west peaks to be 135 ± 22 K. Thus, the asymmetry may not be attributed to a difference in the temperature. Comparing our results with previous modeling works, we conclude that the inner disk is aligned to the outer disk. A shadow cast by the optically thick inner disk has a great influence on the morphology of MIR thermal emission from the outer disk.

  18. Comparison of infrared and 3D digital image correlation techniques applied for mechanical testing of materials

    Science.gov (United States)

    Krstulović-Opara, Lovre; Surjak, Martin; Vesenjak, Matej; Tonković, Zdenko; Kodvanj, Janoš; Domazet, Željko

    2015-11-01

    To investigate the applicability of infrared thermography as a tool for acquiring dynamic yielding in metals, a comparison of infrared thermography with three dimensional digital image correlation has been made. Dynamical tension tests and three point bending tests of aluminum alloys have been performed to evaluate results obtained by IR thermography in order to detect capabilities and limits for these two methods. Both approaches detect pastification zone migrations during the yielding process. The results of the tension test and three point bending test proved the validity of the IR approach as a method for evaluating the dynamic yielding process when used on complex structures such as cellular porous materials. The stability of the yielding process in the three point bending test, as contrary to the fluctuation of the plastification front in the tension test, is of great importance for the validation of numerical constitutive models. The research proved strong performance, robustness and reliability of the IR approach when used to evaluate yielding during dynamic loading processes, while the 3D DIC method proved to be superior in the low velocity loading regimes. This research based on two basic tests, proved the conclusions and suggestions presented in our previous research on porous materials where middle wave infrared thermography was applied.

  19. Performance of a convective, infrared and combined infrared- convective heated conveyor-belt dryer.

    Science.gov (United States)

    El-Mesery, Hany S; Mwithiga, Gikuru

    2015-05-01

    A conveyor-belt dryer was developed using a combined infrared and hot air heating system that can be used in the drying of fruits and vegetables. The drying system having two chambers was fitted with infrared radiation heaters and through-flow hot air was provided from a convective heating system. The system was designed to operate under either infrared radiation and cold air (IR-CA) settings of 2000 W/m(2) with forced ambient air at 30 °C and air flow of 0.6 m/s or combined infrared and hot air convection (IR-HA) dryer setting with infrared intensity set at 2000 W/m(2) and hot at 60 °C being blown through the dryer at a velocity of 0.6 m/s or hot air convection (HA) at an air temperature of 60 °C and air flow velocity 0.6 m/s but without infrared heating. Apple slices dried under the different dryer settings were evaluated for quality and energy requirements. It was found that drying of apple (Golden Delicious) slices took place in the falling rate drying period and no constant rate period of drying was observed under any of the test conditions. The IR-HA setting was 57.5 and 39.1 % faster than IR-CA and HA setting, respectively. Specific energy consumption was lower and thermal efficiency was higher for the IR-HA setting when compared to both IR-CA and HA settings. The rehydration ratio, shrinkage and colour properties of apples dried under IR-HA conditions were better than for either IR-CA or HA.

  20. Structurally Integrated Coatings for Wear and Corrosion (SICWC): Arc Lamp, InfraRed (IR) Thermal Processing

    Energy Technology Data Exchange (ETDEWEB)

    Mackiewicz-Ludtka, G.; Sebright, J. [Caterpillar Corp.

    2007-12-15

    The primary goal of this Cooperative Research and Development Agreement (CRADA) betwe1311 UT-Battelle (Contractor) and Caterpillar Inc. (Participant) was to develop the plasma arc lamp (PAL), infrared (IR) thermal processing technology 1.) to enhance surface coating performance by improving the interfacial bond strength between selected coatings and substrates; and 2.) to extend this technology base for transitioning of the arc lamp processing to the industrial Participant. Completion of the following three key technical tasks (described below) was necessary in order to accomplish this goal. First, thermophysical property data sets were successfully determined for composite coatings applied to 1010 steel substrates, with a more limited data set successfully measured for free-standing coatings. These data are necessary for the computer modeling simulations and parametric studies to; A.) simulate PAL IR processing, facilitating the development of the initial processing parameters; and B.) help develop a better understanding of the basic PAL IR fusing process fundamentals, including predicting the influence of melt pool stirring and heat tnmsfar characteristics introduced during plasma arc lamp infrared (IR) processing; Second, a methodology and a set of procedures were successfully developed and the plasma arc lamp (PAL) power profiles were successfully mapped as a function of PAL power level for the ORNL PAL. The latter data also are necessary input for the computer model to accurately simulate PAL processing during process modeling simulations, and to facilitate a better understand of the fusing process fundamentals. Third, several computer modeling codes have been evaluated as to their capabilities and accuracy in being able to capture and simulate convective mixing that may occur during PAL thermal processing. The results from these evaluation efforts are summarized in this report. The intention of this project was to extend the technology base and provide for

  1. Ground-based Detection of Deuterated Water in Comet C/2014 Q2 (Lovejoy) at IR Wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Paganini, L.; Mumma, M. J.; Villanueva, G. L. [Goddard Center for Astrobiology, NASA Goddard Space Flight Center, Greenbelt, MD (United States); Gibb, E. L. [Department of Physics and Astronomy, University of Missouri, St. Louis, MO (United States)

    2017-02-20

    We conducted a deep search for deuterated water (HDO) in the Oort Cloud comet C/2014 Q2 (Lovejoy), through infrared (IR) spectroscopy with NIRSPEC at the Keck Observatory. In this Letter, we present our detections of HDO and water (H{sub 2}O) in comet Lovejoy on 2015 February 4 (post-perihelion) after 1 hr integration on source. The IR observations allowed simultaneous detection of H{sub 2}O and HDO, yielding production rates of 5.9 ± 0.13 × 10{sup 29} and 3.6 ± 1.0 × 10{sup 26} molecules s{sup −1}, respectively. The simultaneous detection permitted accurate determination of the isotopic ratio (D/H) in water of 3.02 ± 0.87 × 10{sup −4}, i.e., larger than the value for water in terrestrial oceans (or Vienna Standard Mean Ocean Water, VSMOW) by a factor of 1.94 ± 0.56. This D/H ratio in water exceeds the value obtained independently at millimeter wavelengths (0.89 ± 0.25 VSMOW; pre-perihelion). We discuss these parameters in the context of origins and emphasize the need for contemporaneous measurements of HDO and H{sub 2}O.

  2. Ground-based Detection of Deuterated Water in Comet C/2014 Q2 (Lovejoy) at IR Wavelengths

    International Nuclear Information System (INIS)

    Paganini, L.; Mumma, M. J.; Villanueva, G. L.; Gibb, E. L.

    2017-01-01

    We conducted a deep search for deuterated water (HDO) in the Oort Cloud comet C/2014 Q2 (Lovejoy), through infrared (IR) spectroscopy with NIRSPEC at the Keck Observatory. In this Letter, we present our detections of HDO and water (H 2 O) in comet Lovejoy on 2015 February 4 (post-perihelion) after 1 hr integration on source. The IR observations allowed simultaneous detection of H 2 O and HDO, yielding production rates of 5.9 ± 0.13 × 10 29 and 3.6 ± 1.0 × 10 26 molecules s −1 , respectively. The simultaneous detection permitted accurate determination of the isotopic ratio (D/H) in water of 3.02 ± 0.87 × 10 −4 , i.e., larger than the value for water in terrestrial oceans (or Vienna Standard Mean Ocean Water, VSMOW) by a factor of 1.94 ± 0.56. This D/H ratio in water exceeds the value obtained independently at millimeter wavelengths (0.89 ± 0.25 VSMOW; pre-perihelion). We discuss these parameters in the context of origins and emphasize the need for contemporaneous measurements of HDO and H 2 O.

  3. Detecting infrared luminescence and non-chemical signaling of living cells: single cell mid-IR spectroscopy in cryogenic environments

    Science.gov (United States)

    Pereverzev, Sergey

    2017-02-01

    Many life-relevant interaction energies are in IR range, and it is reasonable to believe that some biochemical reactions inside cells can results in emission of IR photons. Cells can use this emission for non-chemical and non-electrical signaling. Detecting weak infrared radiation from live cells is complicated because of strong thermal radiation background and absorption of radiation by tissues. A microfluidic device with live cells inside a vacuum cryogenic environment should suppress this background, and thereby permit observation of live cell auto-luminescence or signaling in the IR regime. One can make IR-transparent windows not emitting in this range, so only the cell and a small amount of liquid around it will emit infrared radiation. Currently mid-IR spectroscopy of single cells requires the use of a synchrotron source to measure absorption or reflection spectra. Decreasing of thermal radiation background will allow absorption and reflection spectroscopy of cells without using synchrotron light. Moreover, cell auto-luminescence can be directly measured. The complete absence of thermal background radiation for cryogenically cooled samples allows the use IR photon-sensitive detectors and obtaining single molecule sensitivity in IR photo-luminescence measurements. Due to low photon energies, photo-luminescence measurements will be non-distractive for pressures samples. The technique described here is based upon US patent 9366574.

  4. MID-INFRARED ATOMIC FINE-STRUCTURE EMISSION-LINE SPECTRA OF LUMINOUS INFRARED GALAXIES: SPITZER/IRS SPECTRA OF THE GOALS SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Inami, H. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Armus, L.; Stierwalt, S.; Díaz-Santos, T.; Surace, J.; Howell, J.; Marshall, J. [Spitzer Science Center, California Institute of Technology, CA 91125 (United States); Charmandaris, V. [Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, GR-71003 Heraklion (Greece); Groves, B. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Kewley, L. [Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Petric, A. [Department of Astronomy, California Institute of Technology, MS 320-47, Pasadena, CA 91125 (United States); Rich, J. [The Observatories, Carnegie Institute of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Haan, S. [CSIRO Astronomy and Space Science, Marsfield, NSW 2122 (Australia); Evans, A. S. [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904 (United States); Mazzarella, J.; Lord, S. [Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States); Appleton, P. [NASA Herschel Science Center, 770 South Wilson Avenue, Pasadena, CA 91125 (United States); Spoon, H. [Astronomy Department, Cornell University, Ithaca, NY 14853 (United States); Frayer, D. [National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944 (United States); Matsuhara, H., E-mail: inami@noao.edu [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (Japan); and others

    2013-11-10

    We present the data and our analysis of mid-infrared atomic fine-structure emission lines detected in Spitzer/Infrared Spectrograph high-resolution spectra of 202 local Luminous Infrared Galaxies (LIRGs) observed as part of the Great Observatories All-sky LIRG Survey (GOALS). We readily detect emission lines of [S IV], [Ne II], [Ne V], [Ne III], [S III]{sub 18.7{sub μm}}, [O IV], [Fe II], [S III]{sub 33.5{sub μm}}, and [Si II]. More than 75% of these galaxies are classified as starburst-dominated sources in the mid-infrared, based on the [Ne V]/[Ne II] line flux ratios and equivalent width of the 6.2 μm polycyclic aromatic hydrocarbon feature. We compare ratios of the emission-line fluxes to those predicted from stellar photo-ionization and shock-ionization models to constrain the physical and chemical properties of the gas in the starburst LIRG nuclei. Comparing the [S IV]/[Ne II] and [Ne III]/[Ne II] line ratios to the Starburst99-Mappings III models with an instantaneous burst history, the emission-line ratios suggest that the nuclear starbursts in our LIRGs have ages of 1-4.5 Myr, metallicities of 1-2 Z{sub ☉}, and ionization parameters of 2-8 × 10{sup 7} cm s{sup –1}. Based on the [S III]{sub 33.5{sub μm}}/[S III]{sub 18.7{sub μm}} ratios, the electron density in LIRG nuclei is typically one to a few hundred cm{sup –3}, with a median electron density of ∼300 cm{sup –3}, for those sources above the low density limit for these lines. We also find that strong shocks are likely present in 10 starburst-dominated sources of our sample. A significant fraction of the GOALS sources (80) have resolved neon emission-line profiles (FWHM ≥600 km s{sup –1}) and five show clear differences in the velocities of the [Ne III] or [Ne V] emission lines, relative to [Ne II], of more than 200 km s{sup –1}. Furthermore, six starburst and five active galactic nucleus dominated LIRGs show a clear trend of increasing line width with ionization potential

  5. Diffusion of n-butane/iso-butane mixtures in silicalite-1 investigated using infrared (IR) microscopy

    NARCIS (Netherlands)

    Chmelik, C.; Heinke, L.; van Baten, J.M.; Krishna, R.

    2009-01-01

    Adsorption and diffusion of n-butane/iso-butane mixtures in individual silicalite-1 crystals has been investigated using infrared (IR) microscopy. The equilibrium sorption isotherm for an equimolar gas phase mixture is calculated using Configurational Bias Monte-Carlo simulations. The comparison

  6. Electronic structure, local magnetism, and spin-orbit effects of Ir(IV)-, Ir(V)-, and Ir(VI)-based compounds

    Energy Technology Data Exchange (ETDEWEB)

    Laguna-Marco, M. A.; Kayser, P.; Alonso, J. A.; Martínez-Lope, M. J.; van Veenendaal, M.; Choi, Y.; Haskel, D.

    2015-06-01

    Element- and orbital-selective x-ray absorption and magnetic circular dichroism measurements are carried out to probe the electronic structure and magnetism of Ir 5d electronic states in double perovskite Sr2MIrO6 (M = Mg, Ca, Sc, Ti, Ni, Fe, Zn, In) and La2NiIrO6 compounds. All the studied systems present a significant influence of spin-orbit interactions in the electronic ground state. In addition, we find that the Ir 5d local magnetic moment shows different character depending on the oxidation state despite the net magnetization being similar for all the compounds. Ir carries an orbital contribution comparable to the spin contribution for Ir4+ (5d(5)) and Ir5+ (5d(4)) oxides, whereas the orbital contribution is quenched for Ir6+ (5d(3)) samples. Incorporation of a magnetic 3d atom allows getting insight into the magnetic coupling between 5d and 3d transition metals. Together with previous susceptibility and neutron diffractionmeasurements, the results indicate that Ir carries a significant local magnetic moment even in samples without a 3d metal. The size of the (small) net magnetization of these compounds is a result of predominant antiferromagnetic interactions between local moments coupled with structural details of each perovskite structure

  7. Infrared sensor for water pollution and monitoring

    Science.gov (United States)

    Baudet, E.; Gutierrez-Arrovo, A.; Bailleul, M.; Rinnert, E.; Nemec, P.; Charrier, J.; Bodiou, L.; Colas, F.; Compère, C.; Boussard, C.; Bureau, B.; Michel, K.; Nazabal, V.

    2017-05-01

    Development of Mid-infrared sensors for the detection of biochemical molecules is a challenge of great importance. Mid-infrared range (4000 - 400 cm-1) contains the absorption bands related to the vibrations of organic molecules (nitrates, hydrocarbons, pesticides, etc.). Chalcogenide glasses are an important class of amorphous materials appropriate for sensing applications. Indeed, they are mainly studied and used for their wide transparency in the infrared range (up to 15 μm for selenide glasses) and high refractive index (between 2 and 3). The aim of this study is to synthesize and characterize chalcogenide thin films for developing mid-IR optical waveguides. Therefore, two (GeSe2)100-x(Sb2Se3)x chalcogenide glasses, where x=10 and 50 were chosen for their good mid-IR transparency, high stability against crystallization and their refractive index contrast suitable for mid-IR waveguiding. Chalcogenide glasses were prepared using the conventional melting and quenching method and then used for RF magnetron sputtering deposition. Sputtered thin films were characterized in order to determine dispersion of refractive index in UV-Vis-NIR-MIR. Obtained results were used for the simulation of the optical design in mid-infrared (λ = 7.7 μm). Selenide ridge waveguide were prepared by RIE-ICP dry etching process. Single-mode propagation at 7.7 μm was observed. Optical losses of 0.7 +/- 0.3 and 2.5 +/- 0.1 dB.cm-1 were measured in near-infrared (λ = 1.55 μm) and midinfrared (λ = 7.7 μm), respectively. Achieved results are promising for the fabrication of an integrated optical sensor operating in the mid-infrared.

  8. Development of plenoptic infrared camera using low dimensional material based photodetectors

    Science.gov (United States)

    Chen, Liangliang

    Infrared (IR) sensor has extended imaging from submicron visible spectrum to tens of microns wavelength, which has been widely used for military and civilian application. The conventional bulk semiconductor materials based IR cameras suffer from low frame rate, low resolution, temperature dependent and highly cost, while the unusual Carbon Nanotube (CNT), low dimensional material based nanotechnology has been made much progress in research and industry. The unique properties of CNT lead to investigate CNT based IR photodetectors and imaging system, resolving the sensitivity, speed and cooling difficulties in state of the art IR imagings. The reliability and stability is critical to the transition from nano science to nano engineering especially for infrared sensing. It is not only for the fundamental understanding of CNT photoresponse induced processes, but also for the development of a novel infrared sensitive material with unique optical and electrical features. In the proposed research, the sandwich-structured sensor was fabricated within two polymer layers. The substrate polyimide provided sensor with isolation to background noise, and top parylene packing blocked humid environmental factors. At the same time, the fabrication process was optimized by real time electrical detection dielectrophoresis and multiple annealing to improve fabrication yield and sensor performance. The nanoscale infrared photodetector was characterized by digital microscopy and precise linear stage in order for fully understanding it. Besides, the low noise, high gain readout system was designed together with CNT photodetector to make the nano sensor IR camera available. To explore more of infrared light, we employ compressive sensing algorithm into light field sampling, 3-D camera and compressive video sensing. The redundant of whole light field, including angular images for light field, binocular images for 3-D camera and temporal information of video streams, are extracted and

  9. Thin film encapsulated 1D thermoelectric detector in an IR microspectrometer

    NARCIS (Netherlands)

    Wu, H.; Emadi, A.; De Graaf, G.; Wolffenbuttel, R.F.

    2010-01-01

    A thermopile-based detector array for use in a miniaturized Infrared (IR) spectrometer has been designed and fabricated using CMOS compatible MEMS technology. The emphasis is on the optimal of the detector array at the system level, while considering the thermal design, the dimensional constraints

  10. Two-dimensional correlation infrared spectroscopy applied to analyzing and identifying the extracts of Baeckea frutescens medicinal materials.

    Science.gov (United States)

    Adib, Adiana Mohamed; Jamaludin, Fadzureena; Kiong, Ling Sui; Hashim, Nuziah; Abdullah, Zunoliza

    2014-08-05

    Baeckea frutescens or locally known as Cucur atap is used as antibacterial, antidysentery, antipyretic and diuretic agent. In Malaysia and Indonesia, they are used as an ingredient of the traditional medicine given to mothers during confinement. A three-steps infra-red (IR) macro-fingerprinting method combining conventional IR spectra, and the secondary derivative spectra with two dimensional infrared correlation spectroscopy (2D-IR) have been proved to be effective methods to examine a complicated mixture such as herbal medicines. This study investigated the feasibility of employing multi-steps IR spectroscopy in order to study the main constituents of B. frutescens and its different extracts (extracted by chloroform, ethyl acetate, methanol and aqueous in turn). The findings indicated that FT-IR and 2D-IR can provide many holistic variation rules of chemical constituents. The structural information of the samples indicated that B. frutescens and its extracts contain a large amount of flavonoids, since some characteristic absorption peaks of flavonoids, such as ∼1600cm(-1), ∼1500cm(-1), ∼1450cm(-1), and ∼1270cm(-1) can be observed. The macroscopical fingerprint characters of FT-IR and 2D-IR spectra can not only provide the information of main chemical constituents in medicinal materials and their different extracts, but also compare the components differences among the similar samples. In conclusion, the multi-steps IR macro-fingerprint method is rapid, effective, visual and accurate for pharmaceutical research. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. FT-IR, FT-Raman spectra and ab initio HF and DFT calculations of 7-chloro-5-(2-chlorophenyl)-3-hydroxy-2,3-dihydro-1H-1,4-benzodiazepin-2-one.

    Science.gov (United States)

    Muthu, S; Prasath, M; Paulraj, E Isac; Balaji, R Arun

    2014-01-01

    The Fourier Transform infrared and Fourier Transform Raman spectra of 7-chloro-5 (2-chlorophenyl)-3-hydroxy-2,3-dihydro-1H-1,4-benzodiazepin-2-one (7C3D4B) were recorded in the regions 4000-400 and 4000-100 cm(-1), respectively. The appropriate theoretical spectrograms for the IR and Raman spectra of the title molecule were also constructed. The calculated results show that the predicted geometry can well reproduce the structural parameters. Predicted vibrational frequencies have been assigned and compared with experimental IR spectra and they supported each other. Stability of the molecule arising from hyperconjugative interactions, charge delocalization and intramolecular hydrogen bond-like weak interaction has been analyzed using natural bond orbital (NBO) analysis by using B3LYP/6-31G(d,p) method. The results show that electron density (ED) in the σ* and π* antibonding orbitals and second-order delocalization energies E(2) confirm the occurrence of intramolecular charge transfer (ICT) within the molecule. The first order hyperpolarizability (βtotal) of this molecular system and related properties (β, μ, and Δα) are calculated using HF/6-31G(d,p) and B3LYP/6-31G(d,p) methods based on the finite-field approach. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Two-dimensional sum-frequency generation (2D SFG) reveals structure and dynamics of a surface-bound peptide

    Science.gov (United States)

    Laaser, Jennifer E.; Skoff, David R.; Ho, Jia-Jung; Joo, Yongho; Serrano, Arnaldo L.; Steinkruger, Jay D.; Gopalan, Padma; Gellman, Samuel H.; Zanni, Martin T.

    2014-01-01

    Surface-bound polypeptides and proteins are increasingly used to functionalize inorganic interfaces such as electrodes, but their structural characterization is exceedingly difficult with standard technologies. In this paper, we report the first two-dimensional sum-frequency generation (2D SFG) spectra of a peptide monolayer, which is collected by adding a mid-IR pulse shaper to a standard femtosecond SFG spectrometer. On a gold surface, standard FTIR spectroscopy is inconclusive about the peptide structure because of solvation-induced frequency shifts, but the 2D lineshapes, anharmonic shifts, and lifetimes obtained from 2D SFG reveal that the peptide is largely α-helical and upright. Random coil residues are also observed, which do not themselves appear in SFG spectra due to their isotropic structural distribution, but which still absorb infrared light and so can be detected by cross-peaks in 2D SFG spectra. We discuss these results in the context of peptide design. Because of the similar way in which the spectra are collected, these 2D SFG spectra can be directly compared to 2D IR spectra, thereby enabling structural interpretations of surface-bound peptides and biomolecules based on the well-studied structure/2D IR spectra relationships established from soluble proteins. PMID:24372101

  13. Infrared spectrometry of Venus: IR Fourier spectrometer on Venera 15 as a precursor of PFS for Venus express

    Science.gov (United States)

    Zasova, L. V.; Moroz, V. I.; Formisano, V.; Ignatiev, N. I.; Khatuntsev, I. V.

    2004-01-01

    Thermal infrared spectrometry in the range 6-40 μm with spectral resolution of 4.5-6.5 cm -1 was realized onboard of Venera 15 for the middle atmosphere of Venus investigations. The 3-D temperature and zonal wind fields ( h, ϕ, LT) in the range 55-100 km and the 3-D aerosol field ( h, ϕ, LT) in the range 55-70 km were retrieved and analyzed. The solar related waves at isobaric levels, generated by the absorbed solar energy, were investigated. In the thermal IR spectral range the, ν1, ν2 and ν3 SO 2 and the H 2O rotational (40 μm) and vibro-rotational (6.3 μm) absorption bands are observed and used for minor compounds retrieval. An advantage of the thermal infrared spectrometry method is that both the temperature and aerosol profiles, which need for retrieval of the vertical profiles of minor compounds, are evaluated from the same spectrum. The Fourier spectrometer on Venera-15 may be considered as a precursor of the Planetary Fourier Spectrometer (PI Prof. V. Formisano), which is included in the payload of the planned Venus Express mission. It has a spectral range 0.9-45 μm, separated into two channels: a short wavelength channel (SWC) in the range 0.9-5 μm and a long wavelength channel (LWC) from 6 to 45 μm, and spectral resolution of 1-2 cm -1. In the history of planetary Fourier spectrometry the PFS is a unique instrument, which possesses a short wavelength channel. A functioning of this instrument on the polar orbit with a good spatial and local time coverage will advance our knowledge in the fundamental problems of the Venus atmosphere.

  14. First-principles study on cubic pyrochlore iridates Y2Ir2O7 and Pr2Ir2O7

    International Nuclear Information System (INIS)

    Ishii, Fumiyuki; Mizuta, Yo Pierre; Kato, Takehiro; Ozaki, Taisuke; Weng Hongming; Onoda, Shigeki

    2015-01-01

    Fully relativistic first-principles electronic structure calculations based on a noncollinear local spin density approximation (LSDA) are performed for pyrochlore iridates Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 . The all-in, all-out antiferromagnetic (AF) order is stablized by the on-site Coulomb repulsion U > U c in the LSDA+U scheme, with U c ∼ 1.1 eV and 1.3 eV for Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 , respectively. AF semimetals with and without Weyl points and then a topologically trivial AF insulator successively appear with further increasing U. For U = 1.3 eV, Y 2 Ir 2 O 7 is a topologically trivial narrow-gap AF insulator having an ordered local magnetic moment ∼0.5μ B /Ir, while Pr 2 Ir 2 O 7 is barely a paramagnetic semimetal with electron and hole concentrations of 0.016/Ir, in overall agreements with experiments. With decreasing oxygen position parameter x describing the trigonal compression of IrO 6 octahedra, Pr 2 Ir 2 O 7 is driven through a non-Fermi-liquid semimetal having only an isolated Fermi point of Γ 8 + , showing a quadratic band touching, to a Z 2 topological insulator. (author)

  15. The TApIR experiment. IR absorption spectra of liquid hydrogen isotopologues

    International Nuclear Information System (INIS)

    Groessle, Robin

    2015-01-01

    The scope of the thesis is the infrared absorption spectroscopy of liquid hydrogen isotopologues with the tritium absorption infrared spectroscopy (TApIR) experiment at the tritium laboratory Karlsruhe (TLK). The calibration process from the sample preparation to the reference measurements are described. A further issue is the classical evaluation of FTIR absorption spectra and the extension using the rolling circle filter (RCF) including the effects on statistical and systematical errors. The impact of thermal and nuclear spin temperature on the IR absorption spectra is discussed. An empirical based modeling for the IR absorption spectra of liquid hydrogen isotopologues is performed.

  16. Limb darkening in Venus night-side disk as viewed from Akatsuki IR2

    Science.gov (United States)

    Satoh, Takehiko; Nakakushi, Takashi; Sato, Takao M.; Hashimoto, George L.

    2017-10-01

    Night-side hemisphere of Venus exhibits dark and bright regions as a result of spatially inhomogeneous cloud opacity which is illuminated by infrared radiation from deeper atmosphere. The 2-μm camera (IR2) onboard Akatsuki, Japan's Venus Climate Orbiter, is equipped with three narrow-band filters (1.735, 2.26, and 2.32 μm) to image Venus night-side disk in well-known transparency windows of CO2 atmosphere (Allen and Crawford 1984). In general, a cloud feature appears brightest when it is in the disk center and becomes darker as the zenith angle of emergent light increases. Such limb darkening was observed with Galileo/NIMS and mathematically approximated (Carlson et al., 1993). Limb-darkening correction helps to identify branches, in a 1.74-μm vs. 2.3-μm radiances scatter plot, each of which corresponds to a group of aerosols with similar properties. We analyzed Akatsuki/IR2 images to characterize the limb darkening for three night-side filters.There is, however, contamination from the intense day-side disk blurred by IR2's point spread function (PSF). It is found that infrared light can be multiplly reflected within the Si substrate of IR2 detector (1024x1024 pixels PtSi array), causing elongated tail in the actual PSF. We treated this in two different ways. One is to mathematically approximate the PSF (with a combination of modified Lorentz functions) and another is to differentiate 2.26-μm image from 2.32-μm image so that the blurred light pattern can directly be obtained. By comparing results from these two methods, we are able to reasonablly clean up the night-side images and limb darkening is extracted. Physical interpretation of limb darkening, as well as "true" time variations of cloud brightness will be presented/discussed.

  17. Acquisition of Infrared Variable Angle Spectroscopic Ellipsometer (IR-VASE)

    Science.gov (United States)

    2016-04-22

    biomaterials , and nanocomposites. Based on this base user group it is estimated that...Engineering; and Barbara Calcagno, Department of General Engineering) 5. The Role of Mechanical Stimulus on Collagen Expression During Bone Repair (Paul...Polymeric Biomaterials Laboratory Principal Investigator: Jorge Almodóvar, PhD - The IR spectra

  18. Structural, phase stability, electronic, elastic properties and hardness of IrN{sub 2} and zinc blende IrN: First-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Zhaobo [Key Laboratory of Advanced Materials of Yunnan Province & Key Laboratory of Advanced Materials of Non-Ferrous and Precious Rare Metals Ministry of Education, Kunming University of Science and Technology, Kunming 650093 (China); Zhou, Xiaolong, E-mail: kmzxlong@163.com [Key Laboratory of Advanced Materials of Yunnan Province & Key Laboratory of Advanced Materials of Non-Ferrous and Precious Rare Metals Ministry of Education, Kunming University of Science and Technology, Kunming 650093 (China); Zhang, Kunhua [State Key Laboratory of Rare Precious Metals Comprehensive Utilization of New Technologies, Kunming Institute of Precious Metals, Kunming 650106 (China)

    2016-12-15

    First-principle calculations were performed to investigate the structural, phase stability, electronic, elastic properties and hardness of monoclinic structure IrN{sub 2} (m-IrN{sub 2}), orthorhombic structure IrN{sub 2} (o-IrN{sub 2}) and zinc blende structure IrN (ZB IrN). The results show us that only m-IrN{sub 2} is both thermodynamic and dynamic stability. The calculated band structure and density of states (DOS) curves indicate that o-IrN{sub 2} and ZB Ir-N compounds we calculated have metallic behavior while m-IrN{sub 2} has a small band gap of ~0.3 eV, and exist a common hybridization between Ir-5d and N-2p states, which forming covalent bonding between Ir and N atoms. The difference charge density reveals the electron transfer from Ir atom to N atom for three Ir-N compounds, which forming strong directional covalent bonds. Notable, a strong N-N bond appeared in m-IrN{sub 2} and o-IrN{sub 2}. The ratio of bulk to shear modulus (B/G) indicate that three Ir-N compounds we calculated are ductile, and ZB IrN possesses a better ductility than two types IrN{sub 2}. m-IrN{sub 2} has highest Debye temperature (736 K), illustrating it possesses strongest covalent bonding. The hardness of three Ir-N compounds were also calculated, and the results reveal that m-IrN{sub 2} (18.23 GPa) and o-IrN{sub 2} (18.02 GPa) are ultraincompressible while ZB IrN has a negative value, which may be attributed to phase transition at ca. 1.98 GPa.

  19. 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...

  20. 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.

  1. Ekologiškų grūdų ir jų produktų pasiūlos veiksniai Lietuvoje

    OpenAIRE

    Pažemeckienė, Ligita

    2010-01-01

    Tyrimo objektas – ekologiškų grūdų ir jų produktų pasiūlos veiksniai. Tyrimo tikslas – išnagrinėjus ekologiškų grūdų ir jų produktų pasiūlos pokyčius, identifikuoti jų gamybos, perdirbimo ir realizavimo problemas bei pasiūlyti sprendimo būdus. Tyrimo uždaviniai: 1) identifikuoti ekologiškų grūdų ir jų produktų rinkų ypatumus, ištirti jų tarpusavio ryšius; 2) nustatyti ekologiškų grūdų ir jų produktų pasiūlos veiksnius; 3) išanalizuoti ekologiškų grūdų ir jų produktų pasiūlos p...

  2. 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...

  3. Interface engineered carbon nanotubes with SiO{sub 2} for flexible infrared detectors

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhenlong [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Gao, Min, E-mail: mingao@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China); Pan, Taisong [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Wei, Xianhua [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang, Sichuan 621010 (China); Chen, Chonglin [Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX 78249 (United States); Department of Physics and the Texas Center for Superconductivity, University of Houston, Houston, TX 77204 (United States); Lin, Yuan, E-mail: linyuan@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China)

    2017-08-15

    Highlights: • Interface engineered carbon nanotubes with SiO{sub 2} is used to construct a kind of flexible infrared detector. • The interface between the MWCNTs and SiO{sub 2} could enhance the IR response speed. • Detector based on the integrated interface of MWCNTs and SiO{sub 2} has successfully detected the movements of the human fingers. - Abstract: Nitrogen-doped/non-doped carbon nanotubes (CNTs) were integrated on SiO{sub 2}/Si and PMMA substrates for understanding the infrared sensing mechanisms. The nanotube structures on SiO{sub 2} substrates exhibit a much shorter response time (about 40 ms) than those directly on PMMA substrates (about 1200 ms), indicating the interface effects between CNTs and the substrates. The infrared responses for both structures show a linear relationship with the light power density even at the radiation power as low as 0.1 mW/mm{sup 2}. Moreover, a new concept flexible IR detector was designed and fabricated by transferring the CNTs/SiO{sub 2} structure onto the PMMA substrate, which exhibits both short response time (50 ms) and good flexibility. The successful detection of human finger movements indicates the practical applications of the CNT-based detectors for the detection of weak thermal or far infrared radiation.

  4. Quantitative gas analysis with FT-IR

    DEFF Research Database (Denmark)

    Bak, J.; Larsen, A.

    1995-01-01

    Calibration spectra of CO in the 2.38-5100 ppm concentration range (22 spectra) have been measured with a spectral resolution of 4 cm(-1), in the mid-IR (2186-2001 cm(-1)) region, with a Fourier transform infrared (FT-IR) instrument. The multivariate calibration method partial least-squares (PLS1...

  5. Non-Linear Optical Studies of IR Materials with Infrared Femtosecond Laser

    Science.gov (United States)

    2016-12-15

    chemical/bio weapon signatures in real time. • IR sources and detectors have a wide ranging applications in public sector from night vision cameras on cars...Jeffrey D. Bude, Andy J. Bayramian, Christopher D. Marshall, Thomas M. Spinka, Constantin L. Haefner, Test station development for laser-induced

  6. Novel two-step laser ablation and ionization mass spectrometry (2S-LAIMS) of actor-spectator ice layers: Probing chemical composition of D2O ice beneath a H2O ice layer

    International Nuclear Information System (INIS)

    Yang, Rui; Gudipati, Murthy S.

    2014-01-01

    In this work, we report for the first time successful analysis of organic aromatic analytes imbedded in D 2 O ices by novel infrared (IR) laser ablation of a layered non-absorbing D 2 O ice (spectator) containing the analytes and an ablation-active IR-absorbing H 2 O ice layer (actor) without the analyte. With these studies we have opened up a new method for the in situ analysis of solids containing analytes when covered with an IR laser-absorbing layer that can be resonantly ablated. This soft ejection method takes advantage of the tenability of two-step infrared laser ablation and ultraviolet laser ionization mass spectrometry, previously demonstrated in this lab to study chemical reactions of polycyclic aromatic hydrocarbons (PAHs) in cryogenic ices. The IR laser pulse tuned to resonantly excite only the upper H 2 O ice layer (actor) generates a shockwave upon impact. This shockwave penetrates the lower analyte-containing D 2 O ice layer (spectator, a non-absorbing ice that cannot be ablated directly with the wavelength of the IR laser employed) and is reflected back, ejecting the contents of the D 2 O layer into the vacuum where they are intersected by a UV laser for ionization and detection by a time-of-flight mass spectrometer. Thus, energy is transmitted from the laser-absorbing actor layer into the non-absorbing spectator layer resulting its ablation. We found that isotope cross-contamination between layers was negligible. We also did not see any evidence for thermal or collisional chemistry of PAH molecules with H 2 O molecules in the shockwave. We call this “shockwave mediated surface resonance enhanced subsurface ablation” technique as “two-step laser ablation and ionization mass spectrometry of actor-spectator ice layers.” This method has its roots in the well-established MALDI (matrix assisted laser desorption and ionization) method. Our method offers more flexibility to optimize both the processes—ablation and ionization. This new technique

  7. Preparation and microwave-infrared absorption of reduced graphene oxide/Cu-Ni ferrite/Al2O3 composites

    Science.gov (United States)

    De-yue, Ma; Xiao-xia, Li; Yu-xiang, Guo; Yu-run, Zeng

    2018-01-01

    Reduced graphene oxide (RGO)/Cu-Ni ferrite/Al2O3 composite was prepared by solvothermal method, and its properties were characterized by SEM, x-ray diffraction, energy-dispersive x-ray spectroscopy and FTIR. The electromagnetic parameters in 2-18 GHz and mid-infrared (IR) spectral transmittance of the composite were measured, respectively. The results show that Cu0.7Ni0.3Fe2O4 nanoparticles with an average size of tens nanometers adsorb on surface of RGO, and meanwhile, Al2O3 nanoparticles adhere to the surface of Cu0.7Ni0.3Fe2O4 nanoparticles and RGO. The composite has both dielectric and magnetic loss mechanism. Its reflection loss is lower than -19 dB in 2-18 GHz, and the maximum of -23.2 dB occurs at 15.6 GHz. With the increasing of Al2O3 amount, its reflection loss becomes lower and the maximum moves towards low frequency slightly. Compared with RGO/Cu-Ni ferrite composites, its magnetic loss and reflection loss slightly reduce with the increasing of Al2O3 amount, and the maximum of reflection loss shifts from a low frequency to a high one. However, its broadband IR absorption is significantly enhanced owing to nano-Al2O3. Therefore, RGO/Cu-Ni ferrite/Al2O3 composites can be used as excellent broadband microwave and IR absorbing materials, and maybe have broad application prospect in electromagnetic shielding, IR absorbing and coating materials.

  8. 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.

  9. Deuterium trapping in the carbon-silicon co-deposition layers prepared by RF sputtering in D2 atmosphere

    Science.gov (United States)

    Zhang, Hongliang; Zhang, Weiyuan; Su, Ranran; Tu, Hanjun; Shi, Liqun; Hu, Jiansheng

    2018-04-01

    Deuterated carbon-silicon layers co-deposited on graphite and silicon substrates by radio frequency magnetron sputtering in pure D2 plasma were produced to study deuterium trapping and characteristics of the C-Si layers. The C-Si co-deposited layers were examined by ion beam analysis (IBA), Raman spectroscopy (RS), infrared absorption (IR) spectroscopy, thermal desorption spectroscopy (TDS) and scanning electron microscopy (SEM). It was found that the growth rate of the C-Si co-deposition layer decreased with increasing temperature from 350 K to 800 K, the D concentration and C/Si ratios increased differently on graphite and silicon substrates. TDS shows that D desorption is mainly as D2, HD, HDO, CD4, and C2D4 and release peaks occurred at temperatures of less than 900 K. RS and IR analysis reveal that the structure of the C-Si layers became more disordered with increasing temperatures. Rounded areas of peeling with 1-2 μm diameters were observed on the surface.

  10. MicrOmega IR: a new infrared hyperspectral imaging microscope or in situ analysis

    Science.gov (United States)

    Vaitua, Leroi; Bibring, Jean-Pierre; Berthé, Michel

    2017-11-01

    MicrOmega IR is an ultra miniaturized Near Infrared hyperspectral microscope for in situ analysis of samples. It is designed to be implemented on board space planetary vehicles (lander and/or rovers). It acquires images of samples typically some 5 mm in width with a spatial sampling of 20 μm. On each pixel, MicrOmega acquires the spectrum in the spectral range 0.9 - 2.6 μm, with a possibility to extend the sensibility up to 4 μm. The spectrum will be measured in up to 300 contiguous spectral channels (600 in the extended range): given the diagnostic spectral features present in this domain, it provides the composition of each spatially resolved constituent. MicrOmega has thus the potential to identify: minerals, such as pyroxene and olivine, ferric oxides, hydrated phases such as phyllosilicates, sulfates and carbonates, ices and organics. The composition of the various phases within a given sample is a critical record of its formation and evolution. Coupled to the mapping information, it provides unique clues to describe the history of the parent body. In particular, the capability to identify hydrated grains and to characterize their adjacent phases has a huge potential in the search for potential bio-relics in Martian samples. This purely non destructive characterization enables further analyses (e.g. through mass spectrometry) to be performed, and/or to contribute to sample selection to return to Earth. MicrOmega IR is coupled to a visible microscope: MicrOmega VIS. Thus, the MicrOmega instrument is developed by an international consortium: IAS (Orsay, France), LESIA (Meudon, France), CBM (Orléans, France), University Of Bern (Bern, Switzerland), IKI (Moscow, Russia). This instrument (MicrOmega IR, MicrOmega VIS and the electronics) is selected for the ESA Exomars mission (launch scheduled for 2013). MicrOmega IR will be used in a reduced spectral range (0.9 - 2.6 μm), due to power, mass and thermal constraints: however, most minerals and other

  11. Calculation of the band structure of GdCo2, GdRh2 e GdIr2 by the APW method

    International Nuclear Information System (INIS)

    Carvalho, J.A.B. de.

    1974-03-01

    The band structure of GdCo 2 , GdRh 2 , GdIr 2 has been calculated by the APW method. A histogram of the density of states is presented for each compound. The bands are transition-metal-like, with s-d hybridization near the Fermi level. The 5d character near the Fermi level increases as one goes from Co to Ir

  12. The Influence of Cholesterol on Fast Dynamics Inside of Vesicle and Planar Phospholipid Bilayers Measured with 2D IR Spectroscopy.

    Science.gov (United States)

    Kel, Oksana; Tamimi, Amr; Fayer, Michael D

    2015-07-23

    Phospholipid bilayers are frequently used as models for cell membranes. Here the influence of cholesterol on the structural dynamics in the interior of 1,2-dilauroyl-sn-glycero-3-phosphocholine (dilauroylphosphatidylcholine, DLPC) vesicles and DLPC planar bilayers are investigated as a function of cholesterol concentration. 2D IR vibrational echo spectroscopy was performed on the antisymmetric CO stretch of the vibrational probe molecule tungsten hexacarbonyl, which is located in the interior alkyl regions of the bilayers. The 2D IR experiments measure spectral diffusion, which is caused by the structural fluctuations of the bilayers. The 2D IR measurements show that the bilayer interior alkyl region dynamics occur on time scales ranging from a few picoseconds to many tens of picoseconds. These are the time scales of the bilayers' structural dynamics, which act as the dynamic solvent bath for chemical processes of membrane biomolecules. The results suggest that at least a significant fraction of the dynamics arise from density fluctuations. Samples are studied in which the cholesterol concentration is varied from 0% to 40% in both the vesicles (72 nm diameter) and fully hydrated planar bilayers in the form of aligned multibilayers. At all cholesterol concentrations, the structural dynamics are faster in the curved vesicle bilayers than in the planar bilayers. As the cholesterol concentration is increased, at a certain concentration there is a sudden change in the dynamics, that is, the dynamics abruptly slow down. However, this change occurs at a lower concentration in the vesicles (between 10% and 15% cholesterol) than in the planar bilayers (between 25% and 30% cholesterol). The sudden change in the dynamics, in addition to other IR observables, indicates a structural transition. However, the results show that the cholesterol concentration at which the transition occurs is influenced by the curvature of the bilayers.

  13. Cationic polyhydrido cluster complexes. Crystal and molecular structures of (Ir3(Ph2P(CH2)3PPh2)3(H)7(CO))2+ and (Ir3(Ph2P(CH2)2(2-py))3(H)7)2+

    International Nuclear Information System (INIS)

    Hsienhau Wang; Casalnuovo, A.L.; Johnson, B.J.; Mueting, A.M.; Pignolet, L.H.

    1988-01-01

    Two new cationic polyhydrido cluster complexes of iridium have been synthesized and characterized by single-crystal x-ray diffraction and by ir and 1 H and 31 P NMR spectroscopy (Ir 3 (dppp) 3 (H) 7 (CO)) 2+ (2) and (Ir3 (PN) 3 (H) 7)2+ (5), where dppp = 1,3-bis(diphenylphosphino)propane and PN = 1-(2-pyridyl)-2-(diphenylphosphino)ethane, were synthesized by the reaction of CO with (Ir 3 (dppp) 3 (H) 7 ) 2+ (1) in CH 2 Cl 2 solution and H 2 with (Ir(PN)(COD)) + (4) in CH 3 OH solution, respectively. Crystal structures for both compounds is reported. The hydride positions were not located in the crystal structure analyses but were deduced from structural and 1 H NMR data. The molecular structure of 2 consists of a bilateral triangle of three iridium atoms with a carbonyl at the vertex and a chelating dppp ligand on each iridium atom. 1 H NMR data with use of acetone-d 6 as solvent showed that 2 possesses four doubly bridging hydrides and three terminal hydrides, yielding C 1 symmetry. The molecular structure of 5 consists of an approximately equilateral triangle of three iridium atoms (average Ir-Ir distance 2.746 (1) angstrom) with one PN ligand chelated to each iridium atom. 1 H NMR analysis, with use of CD 2 Cl 2 as solvent, showed that 5 has one triply bridging hydride and six terminal hydrides, giving C 3 symmetry. (Ir 3 (dppp) 3 (H) 7 (CH 3 C 6 H 4 NC)) 2+ (3) a complex structurally analogous to 2, was synthesized from 1 and p-tolyl isocyanide in CH 2 Cl 2 solution and characterized by ir and 1 H and 31 P NMR spectroscopy. 44 refs., 3 figs., 3 tabs

  14. THE SPECTRAL ENERGY DISTRIBUTIONS AND INFRARED LUMINOSITIES OF z ≈ 2 DUST-OBSCURED GALAXIES FROM Herschel AND Spitzer

    International Nuclear Information System (INIS)

    Melbourne, J.; Soifer, B. T.; Desai, Vandana; Armus, Lee; Pope, Alexandra; Alberts, Stacey; Dey, Arjun; Jannuzi, B. T.; Bussmann, R. S.

    2012-01-01

    Dust-obscured galaxies (DOGs) are a subset of high-redshift (z ≈ 2) optically-faint ultra-luminous infrared galaxies (ULIRGs, e.g., L IR > 10 12 L ☉ ). We present new far-infrared photometry, at 250, 350, and 500 μm (observed-frame), from the Herschel Space Telescope for a large sample of 113 DOGs with spectroscopically measured redshifts. Approximately 60% of the sample are detected in the far-IR. The Herschel photometry allows the first robust determinations of the total infrared luminosities of a large sample of DOGs, confirming their high IR luminosities, which range from 10 11.6 L ☉ IR (8-1000 μm) 13.6 L ☉ . 90% of the Herschel-detected DOGs in this sample are ULIRGs and 30% have L IR > 10 13 L ☉ . The rest-frame near-IR (1-3 μm) spectral energy distributions (SEDs) of the Herschel-detected DOGs are predictors of their SEDs at longer wavelengths. DOGs with 'power-law' SEDs in the rest-frame near-IR show observed-frame 250/24 μm flux density ratios similar to the QSO-like local ULIRG, Mrk 231. DOGs with a stellar 'bump' in their rest-frame near-IR show observed-frame 250/24 μm flux density ratios similar to local star-bursting ULIRGs like NGC 6240. None show 250/24 μm flux density ratios similar to extreme local ULIRG, Arp 220; though three show 350/24 μm flux density ratios similar to Arp 220. For the Herschel-detected DOGs, accurate estimates (within ∼25%) of total IR luminosity can be predicted from their rest-frame mid-IR data alone (e.g., from Spitzer observed-frame 24 μm luminosities). Herschel-detected DOGs tend to have a high ratio of infrared luminosity to rest-frame 8 μm luminosity (the IR8 = L IR (8-1000 μm)/νL ν (8 μm) parameter of Elbaz et al.). Instead of lying on the z = 1-2 'infrared main sequence' of star-forming galaxies (like typical LIRGs and ULIRGs at those epochs) the DOGs, especially large fractions of the bump sources, tend to lie in the starburst sequence. While, Herschel-detected DOGs are similar to scaled up

  15. FT-IR, FT-Raman spectra, density functional computations of the vibrational spectra and molecular conformational analysis of 2,5-di-tert-butyl-hydroquinone

    Science.gov (United States)

    Subramanian, N.; Sundaraganesan, N.; Dereli, Ö.; Türkkan, E.

    2011-12-01

    The purpose of finding conformer among six different possible conformers of 2,5-di-tert-butyl-hydroquinone (DTBHQ), its equilibrium geometry and harmonic wavenumbers were calculated by the B3LYP/6-31G(d,p) method. The infrared and Raman spectra of DTBHQ were recorded in the region 400-4000 cm -1 and 50-3500 cm -1, respectively. In addition, the IR spectra in CCl 4 at various concentrations of DTBHQ are also recorded. The computed vibrational wavenumbers were compared with the IR and Raman experimental data. Computational calculations at B3LYP level with two different basis sets 6-31G(d,p) and 6-311++G(d,p) are also employed in the study of the possible conformer of DTBHQ. The complete assignments were performed on the basis of the potential energy distribution (PED) of the vibrational modes, calculated using VEDA 4 program. The general agreement between the observed and calculated frequencies was established.

  16. Infrared and near infrared emission spectra of TeH and TeD

    Science.gov (United States)

    Yu, Shanshan; Shayesteh, Alireza; Fu, Dejian; Bernath, Peter F.

    2005-04-01

    The vibration-rotation emission spectra for the X2Π ground state and the near infrared emission spectra of the X2Π 1/2- X2Π 3/2 system of the TeH and TeD free radicals have been measured at high resolution using a Fourier transform spectrometer. TeH and TeD were generated in a tube furnace with a DC discharge of a flowing mixture of argon, hydrogen (or deuterium), and tellurium vapor. In the infrared region, for the X2Π 3/2 spin component we observed the 1-0, 2-1, and 3-2 vibrational bands for most of the eight isotopologues of TeH and the 1-0 and 2-1 bands for three isotopologues of TeD. For the X2Π 1/2- X2Π 3/2 transition, we observed the 0-0 and 1-1 bands for TeH and the 0-0, 1-1, and 2-2 bands for TeD. Except for a few lines, the tellurium isotopic shift was not resolved for the X2Π 1/2- X2Π 3/2 transitions of TeH and TeD. Local perturbations with Δ v = 2 between the two spin components of the X2Π state of TeH were found: X2Π 1/2, v = 0 with X2Π 3/2, v = 2; X2Π 1/2, v = 1 with X2Π 3/2, v = 3. The new data were combined with the previous data from the literature and two kinds of fits (Hund's case (a) and Hund's case (c)) were carried out for each of the 10 observed isotopologues: 130TeD, 128TeD, 126TeD, 130TeH, 128TeH, 126TeH, 125TeH, 124TeH, 123TeH, and 122TeH.

  17. From 3 d duality to 2 d duality

    Science.gov (United States)

    Aharony, Ofer; Razamat, Shlomo S.; Willett, Brian

    2017-11-01

    In this paper we discuss 3 d N = 2 supersymmetric gauge theories and their IR dualities when they are compactified on a circle of radius r, and when we take the 2 d limit in which r → 0. The 2 d limit depends on how the mass parameters are scaled as r → 0, and often vacua become infinitely distant in the 2 d limit, leading to a direct sum of different 2 d theories. For generic mass parameters, when we take the same limit on both sides of a duality, we obtain 2 d dualities (between gauge theories and/or Landau-Ginzburg theories) that pass all the usual tests. However, when there are non-compact branches the discussion is subtle because the metric on the moduli space, which is not controlled by supersymmetry, plays an important role in the low-energy dynamics after compactification. Generally speaking, for IR dualities of gauge theories, we conjecture that dualities involving non-compact Higgs branches survive. On the other hand when there is a non-compact Coulomb branch on at least one side of the duality, the duality fails already when the 3 d theories are compactified on a circle. Using the valid reductions we reproduce many known 2 d IR dualities, giving further evidence for their validity, and we also find new 2 d dualities.

  18. 2DCOS and PCMW2D analysis of FT-IR/ATR spectra measured at variable temperatures on-line to a polyurethane polymerization

    Science.gov (United States)

    Schuchardt, Patrick; Unger, Miriam; Siesler, Heinz W.

    2018-01-01

    In the present communication the potential of 2DCOS analysis and the spin-off technique perturbation-correlation moving window 2D (PCMW2D) analysis is illustrated with reference to spectroscopic changes observed in a data set recorded by in-line fiber-coupled FT-IR spectroscopy in the attenuated total reflection (ATR) mode during a polyurethane solution polymerization at different temperatures. In view of the chemical functionalities involved, hydrogen bonding plays an important role in this polymerization reaction. Based on the 2DCOS and PCMW2D analysis, the sequence of hydrogen bonding changes accompanying the progress of polymerization and precipitation of solid polymer can be determined. Complementary to the kinetic data derived from the original variable-temperature spectra in a previous publication the results provide a more detailed picture of the investigated solution polymerization.

  19. Application of fourier-transform infrared (ft-ir) spectroscopy for determination of total phenolics of freeze dried lemon juices

    International Nuclear Information System (INIS)

    Sherazi, S.T.H.; Bhutto, A.A.; Mehesar, S.A.

    2017-01-01

    A cost effective and environmentally safe analytical method for rapid assessment of total phenolic content (TPC) in freeze dried lemon juice samples was developed using transmission Fourier-transform infrared spectroscopy (FT-IR) in conjunction with chemometric techniques. Two types of calibrations i.e. simple Beer's law and partial least square (PLS) were applied to investigate most accurate calibration model based on region from1420 to 1330 cm-1. The better analytical performance was obtained by PLS technique coefficient of determination (R2), root mean square error of calibration (RMSEC) with the value of 0.999 and 0.00864, respectively. The results of TPC in freeze dried lemon juice samples obtained by transmission FT-IR were compared with TPC observed by Folin-Ciocalteu (FC) assay and found to be comparable. Outcomes of the present study indicate that transmission FT-IR spectroscopic approach could be used as an alternative approach in place of Folin-Ciocalteu (FC) assay which is expensive and time-consuming conventional chemical methods for determination of the total phenolic content of lemon fruits. (author)

  20. Mid-IR absorption sensing of heavy water using a silicon-on-sapphire waveguide.

    Science.gov (United States)

    Singh, Neetesh; Casas-Bedoya, Alvaro; Hudson, Darren D; Read, Andrew; Mägi, Eric; Eggleton, Benjamin J

    2016-12-15

    We demonstrate a compact silicon-on-sapphire (SOS) strip waveguide sensor for mid-IR absorption spectroscopy. This device can be used for gas and liquid sensing, especially to detect chemically similar molecules and precisely characterize extremely absorptive liquids that are difficult to detect by conventional infrared transmission techniques. We reliably measure concentrations up to 0.25% of heavy water (D2O) in a D2O-H2O mixture at its maximum absorption band at around 4 μm. This complementary metal-oxide-semiconductor (CMOS) compatible SOS D2O sensor is promising for applications such as measuring body fat content or detection of coolant leakage in nuclear reactors.

  1. Infrared spectroscopic ellipsometry of micrometer-sized SiO2 line gratings

    Science.gov (United States)

    Walder, Cordula; Zellmeier, Matthias; Rappich, Jörg; Ketelsen, Helge; Hinrichs, Karsten

    2017-09-01

    For the design and process control of periodic nano-structured surfaces spectroscopic ellipsometry is already established in the UV-VIS spectral regime. The objective of this work is to show the feasibility of spectroscopic ellipsometry in the infrared, exemplarily, on micrometer-sized SiO2 line gratings grown on silicon wafers. The grating period ranges from 10 to about 34 μm. The IR-ellipsometric spectra of the gratings exhibit complex changes with structure variations. Especially in the spectral range of the oxide stretching modes, the presence of a Rayleigh singularity can lead to pronounced changes of the spectrum with the sample geometry. The IR-ellipsometric spectra of the gratings are well reproducible by calculations with the RCWA method (Rigorous Coupled Wave Analysis). Therefore, infrared spectroscopic ellipsometry allows the quantitative characterization and process control of micrometer-sized structures.

  2. Prelaunch calibrations and on-orbit performance analysis of FY-2D SVISSR infrared channels

    Science.gov (United States)

    Zhang, Yong; Chen, Fuchun

    2014-10-01

    Meteorological satellites have become an irreplaceable weather and ocean-observing tool in China. These satellites are used to monitor natural disasters and improve the efficiency of many sectors of Chinese national economy. FY-2 series satellites are one of the key components of Chinese meteorological observing system and application system. In this paper, the operational satellite- FY-2D's infrared channels were focused and analyzed. The instruments' background was introduced briefly. The main payload SVISSR specifications were compared with its ancestral VISSR. The optical structure of the SVISSR was also expressed. FY-2D prelaunch calibrations methodology was introduced and the accuracies of the absolute radiometric calibration were analyzed. Some key optics on-orbit performance of FY-2D SVISSR were analyzed include onboard blackbody, cold FPA and detector noise level. All of these works show that FY- 2D's main payload SVISSR was in a healthy status.

  3. Vibrational correlation between conjugated carbonyl and diazo modes studied by single- and dual-frequency two-dimensional infrared spectroscopy

    Science.gov (United States)

    Maekawa, Hiroaki; Sul, Soohwan; Ge, Nien-Hui

    2013-08-01

    We have applied infrared three-pulse photon echo and single- and dual-frequency 2D IR spectroscopy to the ester Cdbnd O and diazo Ndbnd N stretching modes in ethyl diazoacetate (EDA), and investigated their vibrational frequency fluctuations and correlation. The two modes exhibit different vibrational dynamics and 2D lineshape, which are well simulated by frequency-frequency correlation functions (FFCFs) with two decaying components. Although the FT IR spectrum shows a single Cdbnd O band, absolute magnitude 2D IR nonrephasing spectrum displays spectral signatures supporting the presence of cis and trans conformations. The cross-peak inclined toward the anti-diagonal in the dual-frequency 2D IR spectrum, indicating that the frequency fluctuations of the two modes are anticorrelated. This behavior is attributed to anticorrelated change in the bond orders when solvent and structural fluctuations causes EDA to adopt a different mixture of the two dominant resonance structures. The effects of cross FFCF on the cross-peak line shape are discussed.

  4. Overexpression of IRS2 in isolated pancreatic islets causes proliferation and protects human β-cells from hyperglycemia-induced apoptosis

    International Nuclear Information System (INIS)

    Mohanty, S.; Spinas, G.A.; Maedler, K.; Zuellig, R.A.; Lehmann, R.; Donath, M.Y.; Trueb, T.; Niessen, M.

    2005-01-01

    Studies in vivo indicate that IRS2 plays an important role in maintaining functional β-cell mass. To investigate if IRS2 autonomously affects β-cells, we have studied proliferation, apoptosis, and β-cell function in isolated rat and human islets after overexpression of IRS2 or IRS1. We found that β-cell proliferation was significantly increased in rat islets overexpressing IRS2 while IRS1 was less effective. Moreover, proliferation of a β-cell line, INS-1, was decreased after repression of Irs2 expression using RNA oligonucleotides. Overexpression of IRS2 in human islets significantly decreased apoptosis of β-cells, induced by 33.3 mM D-glucose. However, IRS2 did not protect cultured rat islets against apoptosis in the presence of 0.5 mM palmitic acid. Overexpression of IRS2 in isolated rat islets significantly increased basal and D-glucose-stimulated insulin secretion as determined in perifusion experiments. Therefore, IRS2 is sufficient to induce proliferation in rat islets and to protect human β-cells from D-glucose-induced apoptosis. In addition, IRS2 can improve β-cell function. Our results indicate that IRS2 acts autonomously in β-cells in maintenance and expansion of functional β-cell mass in vivo

  5. 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

  6. Vibrational correlation between conjugated carbonyl and diazo modes studied by single- and dual-frequency two-dimensional infrared spectroscopy

    International Nuclear Information System (INIS)

    Maekawa, Hiroaki; Sul, Soohwan; Ge, Nien-Hui

    2013-01-01

    Highlights: ► Vibrational dynamics of conjugated C=O and N=N modes of ethyl diazoacetate was studied. ► Their frequency–frequency correlation functions are different. ► The dual-frequency 2D IR spectrum indicates anticorrelated frequency fluctuations. ► Correlation effects on dual-frequency 2D IR spectra are discussed. ► The existence of cis and trans conformers is revealed in 2D IR spectra. - Abstract: We have applied infrared three-pulse photon echo and single- and dual-frequency 2D IR spectroscopy to the ester C=O and diazo N=N stretching modes in ethyl diazoacetate (EDA), and investigated their vibrational frequency fluctuations and correlation. The two modes exhibit different vibrational dynamics and 2D lineshape, which are well simulated by frequency–frequency correlation functions (FFCFs) with two decaying components. Although the FT IR spectrum shows a single C=O band, absolute magnitude 2D IR nonrephasing spectrum displays spectral signatures supporting the presence of cis and trans conformations. The cross-peak inclined toward the anti-diagonal in the dual-frequency 2D IR spectrum, indicating that the frequency fluctuations of the two modes are anticorrelated. This behavior is attributed to anticorrelated change in the bond orders when solvent and structural fluctuations causes EDA to adopt a different mixture of the two dominant resonance structures. The effects of cross FFCF on the cross-peak line shape are discussed

  7. Vibrational correlation between conjugated carbonyl and diazo modes studied by single- and dual-frequency two-dimensional infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Hiroaki; Sul, Soohwan [Department of Chemistry, University of California at Irvine, Irvine, CA 92697-2025 (United States); Ge, Nien-Hui, E-mail: nhge@uci.edu [Department of Chemistry, University of California at Irvine, Irvine, CA 92697-2025 (United States)

    2013-08-30

    Highlights: ► Vibrational dynamics of conjugated C=O and N=N modes of ethyl diazoacetate was studied. ► Their frequency–frequency correlation functions are different. ► The dual-frequency 2D IR spectrum indicates anticorrelated frequency fluctuations. ► Correlation effects on dual-frequency 2D IR spectra are discussed. ► The existence of cis and trans conformers is revealed in 2D IR spectra. - Abstract: We have applied infrared three-pulse photon echo and single- and dual-frequency 2D IR spectroscopy to the ester C=O and diazo N=N stretching modes in ethyl diazoacetate (EDA), and investigated their vibrational frequency fluctuations and correlation. The two modes exhibit different vibrational dynamics and 2D lineshape, which are well simulated by frequency–frequency correlation functions (FFCFs) with two decaying components. Although the FT IR spectrum shows a single C=O band, absolute magnitude 2D IR nonrephasing spectrum displays spectral signatures supporting the presence of cis and trans conformations. The cross-peak inclined toward the anti-diagonal in the dual-frequency 2D IR spectrum, indicating that the frequency fluctuations of the two modes are anticorrelated. This behavior is attributed to anticorrelated change in the bond orders when solvent and structural fluctuations causes EDA to adopt a different mixture of the two dominant resonance structures. The effects of cross FFCF on the cross-peak line shape are discussed.

  8. Diphosphine- and CO-Induced Fragmentation of Chloride-bridged Dinuclear Complex and Cp*Ir(mu-Cl)(3)Re(CO)(3) and Attempted Synthesis of Cp*Ir(mu-Cl)(3)Mn(CO)(3): Spectroscopic Data and X-ray Diffraction Structures of the Pentamethylcyclopentadienyl Compounds [Cp*IrCl{(Z)-Ph2PCH = CHPPh2}][Cl]center dot 2CHCl(3) and Cp*Ir(CO)Cl-2

    Energy Technology Data Exchange (ETDEWEB)

    Hammons, Casey [University of North Texas; Wang, Xiaoping [ORNL; Nesterov, Vladimir [University of North Texas; Richmond, Michael G. [University of North Texas

    2010-01-01

    The confacial bioctahedral compound Cp*Ir(mu-Cl)(3)Re(CO)(3) (1) undergoes rapid fragmentation in the presence of the unsaturated diphosphine ligand (Z)-Ph2PCH = CHPPh2 to give the mononuclear compounds [Cp*IrCl {(Z)-Ph2PCH = CHPPh2}][Cl] (2) and fac-ClRe(CO)(3)[(Z)-Ph2PCH = CHPPh2] (3). 2 has been characterized by H-1 and P-31 NMR spectroscopy and X-ray diffraction analysis. 2 center dot 2CHCl(3) crystallizes in the monoclinic space group C2/c, a = 35.023 (8) angstrom, b = 10.189 (2) angstrom, c = 24.003 (6) angstrom, b = 103.340 (3), V = 8,335 (3) angstrom 3, Z = 8, and d(calc) = 1.647 Mg/m(3); R = 0.0383, R-w = 0.1135 for 8,178 reflections with I> 2 sigma(I). The Ir(III) center in 2 exhibits a six-coordinate geometry and displays a chelating diphosphine group. Compound 1 reacts with added CO with fragmentation to yield the known compounds Cp*Ir(CO)Cl-2 (4) and ClRe(CO)(5) (5) in near quantitative yield by IR spectroscopy. Using the protocol established by our groups for the synthesis of 1, we have explored the reaction of [Cp*IrCl2](2) with ClMn(CO)(5) as a potential route to Cp*Ir(mu-Cl)(3)Mn(CO)(3); unfortunately, 4 was the only product isolated from this reaction. The solid-state structure of 4 was determined by X-ray diffraction analysis. 4 crystallizes in the triclinic space group P-1, a = 7.4059 (4) angstrom, b = 7.8940 (4) angstrom, c = 11.8488 (7) angstrom, alpha = 80.020 (1), beta = 79.758 (1), gamma = 68.631 (1), V = 630.34 (6) angstrom(3), Z = 2, and d(calc) = 2.246 Mg/m(3); R = 0.0126, R-w = 0.0329 for 2,754 reflections with I> 2 sigma(I). The expected three-legged piano-stool geometry in 4 has been crystallographically confirmed.

  9. Late gadolinium enhancement cardiac imaging on a 3T scanner with parallel RF transmission technique: prospective comparison of 3D-PSIR and 3D-IR

    International Nuclear Information System (INIS)

    Schultz, Anthony; Caspar, Thibault; Schaeffer, Mickael; Labani, Aissam; Jeung, Mi-Young; El Ghannudi, Soraya; Roy, Catherine; Ohana, Mickael

    2016-01-01

    To qualitatively and quantitatively compare different late gadolinium enhancement (LGE) sequences acquired at 3T with a parallel RF transmission technique. One hundred and sixty participants prospectively enrolled underwent a 3T cardiac MRI with 3 different LGE sequences: 3D Phase-Sensitive Inversion-Recovery (3D-PSIR) acquired 5 minutes after injection, 3D Inversion-Recovery (3D-IR) at 9 minutes and 3D-PSIR at 13 minutes. All LGE-positive patients were qualitatively evaluated both independently and blindly by two radiologists using a 4-level scale, and quantitatively assessed with measurement of contrast-to-noise ratio and LGE maximal surface. Statistical analyses were calculated under a Bayesian paradigm using MCMC methods. Fifty patients (70 % men, 56yo ± 19) exhibited LGE (62 % were post-ischemic, 30 % related to cardiomyopathy and 8 % post-myocarditis). Early and late 3D-PSIR were superior to 3D-IR sequences (global quality, estimated coefficient IR > early-PSIR: -2.37 CI = [-3.46; -1.38], prob(coef > 0) = 0 % and late-PSIR > IR: 3.12 CI = [0.62; 4.41], prob(coef > 0) = 100 %), LGE surface estimated coefficient IR > early-PSIR: -0.09 CI = [-1.11; -0.74], prob(coef > 0) = 0 % and late-PSIR > IR: 0.96 CI = [0.77; 1.15], prob(coef > 0) = 100 %. Probabilities for late PSIR being superior to early PSIR concerning global quality and CNR were over 90 %, regardless of the aetiological subgroup. In 3T cardiac MRI acquired with parallel RF transmission technique, 3D-PSIR is qualitatively and quantitatively superior to 3D-IR. (orig.)

  10. Novel two-step laser ablation and ionization mass spectrometry (2S-LAIMS) of actor-spectator ice layers: Probing chemical composition of D{sub 2}O ice beneath a H{sub 2}O ice layer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rui, E-mail: ryang73@ustc.edu; Gudipati, Murthy S., E-mail: gudipati@jpl.nasa.gov [Science Division, Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 183-301, 4800 Oak Grove Drive, Pasadena, California 91109 (United States)

    2014-03-14

    In this work, we report for the first time successful analysis of organic aromatic analytes imbedded in D{sub 2}O ices by novel infrared (IR) laser ablation of a layered non-absorbing D{sub 2}O ice (spectator) containing the analytes and an ablation-active IR-absorbing H{sub 2}O ice layer (actor) without the analyte. With these studies we have opened up a new method for the in situ analysis of solids containing analytes when covered with an IR laser-absorbing layer that can be resonantly ablated. This soft ejection method takes advantage of the tenability of two-step infrared laser ablation and ultraviolet laser ionization mass spectrometry, previously demonstrated in this lab to study chemical reactions of polycyclic aromatic hydrocarbons (PAHs) in cryogenic ices. The IR laser pulse tuned to resonantly excite only the upper H{sub 2}O ice layer (actor) generates a shockwave upon impact. This shockwave penetrates the lower analyte-containing D{sub 2}O ice layer (spectator, a non-absorbing ice that cannot be ablated directly with the wavelength of the IR laser employed) and is reflected back, ejecting the contents of the D{sub 2}O layer into the vacuum where they are intersected by a UV laser for ionization and detection by a time-of-flight mass spectrometer. Thus, energy is transmitted from the laser-absorbing actor layer into the non-absorbing spectator layer resulting its ablation. We found that isotope cross-contamination between layers was negligible. We also did not see any evidence for thermal or collisional chemistry of PAH molecules with H{sub 2}O molecules in the shockwave. We call this “shockwave mediated surface resonance enhanced subsurface ablation” technique as “two-step laser ablation and ionization mass spectrometry of actor-spectator ice layers.” This method has its roots in the well-established MALDI (matrix assisted laser desorption and ionization) method. Our method offers more flexibility to optimize both the processes—ablation and

  11. Magnetic heat transport in Sr{sub 2}IrO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Steckel, Frank [Leibniz Institute for Solid State and Materials Research, IFW Dresden (Germany); Takagi, Hidenori [Max-Planck-Institute for Solid State Research, Stuttgart (Germany); Buechner, Bernd; Hess, Christian [Leibniz Institute for Solid State and Materials Research, IFW Dresden (Germany); Center for Transport and Devices, TU Dresden (Germany)

    2015-07-01

    The layered perovskite Sr{sub 2}IrO{sub 4} is a 5d transition metal oxide with an enhanced spin-orbit coupling leading to a Mott insulating ground state with J{sub eff}=(1)/(2). It exhibits canted antiferromagnetism below T{sub N}=240 K with an antiferromagnetic coupling constant of about J=0.1 eV. Thermal conductivity measurements along the ab plane of a Sr{sub 2}IrO{sub 4} single crystal provide evidence for a contribution of magnons (below T{sub N}) to the thermal conductivity, similar to that of the isostructural 2D S=(1)/(2) Heisenberg antiferromagnet La{sub 2}CuO{sub 4}, where a significant magnonic contribution to the heat transport is known.

  12. Infrared and swelling study of the hydration-induced phase transition of wet-spun hyaluronate films

    Science.gov (United States)

    Hoppe, A. D.; Marlowe, R. L.; Lee, S. A.; Powell, J. W.; Rupprecht, A.

    1997-03-01

    The hydration properties of wet-spun films of hyaluronate (HA) with four different counterions (Li^+, Cs^+, Mg^2+, and Ca^2+) have been studied using optical microscopy, optical birefringence and infrared (IR) spectroscopy. Small pieces of these films were found to be optically birefringent up to hydration levels near 90 % relative humidity (RH). All four kinds of films then became optically isotropic and display dramatic changes in size. These changes are consistent with the occurrence of an order-disorder (o-d) transition. IR spectroscopy of the backbone region (from 800 to 1000 cm-1) suggests that the Li^+, Cs^+ and Ca^2+ films are very similar. Two IR bands in this region are observed at low RH and show no dependence on hydration until the o-d transition. The IR spectra of CaHA show five bands in this region. These five bands are observed to 95 % RH.

  13. IR-laser assisted additive freeform optics manufacturing.

    Science.gov (United States)

    Hong, Zhihan; Liang, Rongguang

    2017-08-02

    Computer-controlled additive manufacturing (AM) processes, also known as three-dimensional (3D) printing, create 3D objects by the successive adding of a material or materials. While there have been tremendous developments in AM, the 3D printing of optics is lagging due to the limits in materials and tight requirements for optical applicaitons. We propose a new precision additive freeform optics manufacturing (AFOM) method using an pulsed infrared (IR) laser. Compared to ultraviolet (UV) curable materials, thermally curable optical silicones have a number of advantages, such as strong UV stability, non-yellowing, and high transmission, making it particularly suitable for optical applications. Pulsed IR laser radiation offers a distinct advantage in processing optical silicones, as the high peak intensity achieved in the focal region allows for curing the material quickly, while the brief duration of the laser-material interaction creates a negligible heat-affected zone.

  14. Fourier Transform Infrared Spectroscopy (FT-IR) and Simple Algorithm Analysis for Rapid and Non-Destructive Assessment of Developmental Cotton Fibers.

    Science.gov (United States)

    Liu, Yongliang; Kim, Hee-Jin

    2017-06-22

    With cotton fiber growth or maturation, cellulose content in cotton fibers markedly increases. Traditional chemical methods have been developed to determine cellulose content, but it is time-consuming and labor-intensive, mostly owing to the slow hydrolysis process of fiber cellulose components. As one approach, the attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy technique has also been utilized to monitor cotton cellulose formation, by implementing various spectral interpretation strategies of both multivariate principal component analysis (PCA) and 1-, 2- or 3-band/-variable intensity or intensity ratios. The main objective of this study was to compare the correlations between cellulose content determined by chemical analysis and ATR FT-IR spectral indices acquired by the reported procedures, among developmental Texas Marker-1 (TM-1) and immature fiber ( im ) mutant cotton fibers. It was observed that the R value, CI IR , and the integrated intensity of the 895 cm -1 band exhibited strong and linear relationships with cellulose content. The results have demonstrated the suitability and utility of ATR FT-IR spectroscopy, combined with a simple algorithm analysis, in assessing cotton fiber cellulose content, maturity, and crystallinity in a manner which is rapid, routine, and non-destructive.

  15. Rapid authentication and identification of different types of A. roxburghii by Tri-step FT-IR spectroscopy

    Science.gov (United States)

    Chen, Ying; Huang, Jinfang; Yeap, Zhao Qin; Zhang, Xue; Wu, Shuisheng; Ng, Chiew Hoong; Yam, Mun Fei

    2018-06-01

    Anoectochilus roxburghii (Wall.) Lindl. (Orchidaceae) is a precious traditional Chinese medicinal herb and has been perennially used to treat various illness. However, there were unethical sellers who adulterated wild A. roxburghii with tissue cultured and cultivated ones. Therefore, there is an urgent need for an effective authentication method to differentiate between these different types of A. roxburghii. In this research, the infrared spectroscopic tri-step identification approach including Fourier transform infrared spectroscopy (FT-IR), Second derivative infrared spectra (SD-IR) and two-dimensional correlation infrared spectra (2D-IR) was used to develop a simple and rapid method to discriminate between wild, cultivated and tissue cultivated A. roxburghii plant. Through this study, all three types of A. roxburghii plant were successfully identified and discriminated through the infrared spectroscopic tri-step identification method. Besides that, all the samples of wild, cultivated and tissue cultivated A. roxburghii plant were analysed with the Soft Independent Modelling of Class Analogy (SIMCA) pattern recognition technique to test and verify the experimental results. The results showed that the three types of A. roxburghii can be discriminated clearly as the recognition rate was 100% for all three types and the rejection rate was more than 60%. 70% of the validated samples were also identified correctly by the SIMCA model. The SIMCA model was also validated by comparing 70 standard herbs to the model. As a result, it was demonstrated that the macroscopic IR fingerprint method and the classification analysis could discriminate not only between the A. roxburghi samples and the standard herbs, it could also distinguish between the three different types of A. roxburghi plant in a direct, rapid and holistic manner.

  16. IR Sensor Synchronizing Active Shutter Glasses for 3D HDTV with Flexible Liquid Crystal Lenses

    Directory of Open Access Journals (Sweden)

    Jeong In Han

    2013-12-01

    Full Text Available IR sensor synchronizing active shutter glasses for three-dimensional high definition television (3D HDTV were developed using a flexible liquid crystal (FLC lens. The FLC lens was made on a polycarbonate (PC substrate using conventional liquid crystal display (LCD processes. The flexible liquid crystal lens displayed a maximum transmission of 32% and total response time of 2.56 ms. The transmittance, the contrast ratio and the response time of the flexible liquid crystal lens were superior to those of glass liquid crystal lenses. Microcontroller unit and drivers were developed as part of a reception module with power supply for the IR sensor synchronizing active shutter glasses with the flexible liquid crystal lens prototypes. IR sensor synchronizing active shutter glasses for 3D HDTV with flexible liquid crystal lenses produced excellent 3D images viewing characteristics.

  17. Research into the usage of integrated jamming of IR weakening and smoke-screen resisting the IR imaging guided missiles

    Science.gov (United States)

    Wang, Long-tao; Jiang, Ning; Lv, Ming-shan

    2015-10-01

    With the emergence of the anti-ship missle with the capability of infrared imaging guidance, the traditional single jamming measures, because of the jamming mechanism and technical flaws or unsuitable use, greatly reduced the survival probability of the war-ship in the future naval battle. Intergrated jamming of IR weakening + smoke-screen Can not only make jamming to the search and tracking of IR imaging guidance system , but also has feasibility in conjunction, besides , which also make the best jamming effect. The research conclusion has important realistic meaning for raising the antimissile ability of surface ships. With the development of guidance technology, infrared guidance system has expanded by ir point-source homing guidance to infrared imaging guidance, Infrared imaging guidance has made breakthrough progress, Infrared imaging guidance system can use two-dimensional infrared image information of the target, achieve the precise tracking. Which has Higher guidance precision, better concealment, stronger anti-interference ability and could Target the key parts. The traditional single infrared smoke screen jamming or infrared decoy flare interference cannot be imposed effective interference. So, Research how to effectively fight against infrared imaging guided weapons threat measures and means, improving the surface ship antimissile ability is an urgent need to solve.

  18. Thermalization in 2D critical quench and UV/IR mixing

    Science.gov (United States)

    Mandal, Gautam; Paranjape, Shruti; Sorokhaibam, Nilakash

    2018-01-01

    We consider quantum quenches in models of free scalars and fermions with a generic time-dependent mass m( t) that goes from m 0 to zero. We prove that, as anticipated in MSS [1], the post-quench dynamics can be described in terms of a state of the generalized Calabrese-Cardy form | ψ〉 = exp[- κ 2 H - ∑ n >2 ∞ κ n W n ]|Bd〉. The W n ( n = 2, 3, . . ., W 2 = H) here represent the conserved W ∞ charges and |Bd〉 represents a conformal boundary state. Our result holds irrespective of whether the pre-quench state is a ground state or a squeezed state, and is proved without recourse to perturbation expansion in the κ n 's as in MSS. We compute exact time-dependent correlators for some specific quench protocols m( t). The correlators explicitly show thermalization to a generalized Gibbs ensemble (GGE), with inverse temperature β = 4 κ 2, and chemical potentials μ n = 4 κ n . In case the pre-quench state is a ground state, it is possible to retrieve the exact quench protocol m( t) from the final GGE, by an application of inverse scattering techniques. Another notable result, which we interpret as a UV/IR mixing, is that the long distance and long time (IR) behaviour of some correlators depends crucially on all κ n 's, although they are highly irrelevant couplings in the usual RG parlance. This indicates subtleties in RG arguments when applied to non-equilibrium dynamics.

  19. Comparison of Fiber Optic and Conduit Attenuated Total Reflection (ATR) Fourier Transform Infrared (FT-IR) Setup for In-Line Fermentation Monitoring.

    Science.gov (United States)

    Koch, Cosima; Posch, Andreas E; Herwig, Christoph; Lendl, Bernhard

    2016-12-01

    The performance of a fiber optic and an optical conduit in-line attenuated total reflection mid-infrared (IR) probe during in situ monitoring of Penicillium chrysogenum fermentation were compared. The fiber optic probe was connected to a sealed, portable, Fourier transform infrared (FT-IR) process spectrometer via a plug-and-play interface. The optical conduit, on the other hand, was connected to a FT-IR process spectrometer via a knuckled probe with mirrors that had to be adjusted prior to each fermentation, which were purged with dry air. Penicillin V (PenV) and its precursor phenoxyacetic acid (POX) concentrations were determined by online high-performance liquid chromatography and the obtained concentrations were used as reference to build partial least squares regression models. Cross-validated root-mean-square errors of prediction were found to be 0.2 g L -1 (POX) and 0.19 g L -1 (PenV) for the fiber optic setup and 0.17 g L -1 (both POX and PenV) for the conduit setup. Higher noise-levels and spectrum-to-spectrum variations of the fiber optic setup lead to higher noise of estimated (i.e., unknown) POX and PenV concentrations than was found for the conduit setup. It seems that trade-off has to be made between ease of handling (fiber optic setup) and measurement accuracy (optical conduit setup) when choosing one of these systems for bioprocess monitoring. © The Author(s) 2016.

  20. Composition dependence of electrical properties of ZnF2–MO–TeO2 ...

    Indian Academy of Sciences (India)

    Unknown

    concentrations of MO (P2O5, As2O3 and Bi2O3) were measured as a function of frequency and temperature over moderately ... affect the far infrared transmission of tellurite glasses to a less extent ... with differential thermal analysis (DTA) and infrared spectra (IR). ... density (d) of the glasses was determined to an accuracy.

  1. Mode structure in an optically pumped D2O far infrared ring laser

    International Nuclear Information System (INIS)

    Yuan, D.C.; Soumagne, G.; Siegrist, M.R.

    1989-07-01

    The mode structures in an optically pumped D 2 O far infrared ring laser and a corresponding linear resonator have been compared. While single mode operation can be obtained over the whole useful pressure range in the ring structure, this is only possible at pressures greater than 8 Torr in the linear resonator case. A numerical model predicts quite well the pulse shape, pressure dependence and influence of the resonator quality in the ring cavity. (author) 12 figs., 8 refs

  2. Optical properties of reduced graphene oxide and CuFe2O4 composites in the IR region

    Science.gov (United States)

    Ma, De-yue; Li, Xiao-xia; Guo, Yu-xiang; Zeng, Yu-run

    2018-01-01

    The complex refractive index of reduced graphene oxide and CuFe2O4 composites prepared by hydrothermal method was calculated using infrared Micro-reflective spectra and K-K relation, and the calculation errors were analyzed according to its IR transmission and spectral reflectivity calculated by Fresnel formula. And then normal emissivity of the composite in IR atmospheric window was calculated by means of Fresnel formula and modified refraction angle formula. The calculation accuracy was verified by comparing measured normal total emissivity with the calculated one. The results show that complex refractive index and normal emissivity calculated by the formulas have a high accuracy. It has been found that the composite has a good absorption and radiation characteristics in IR atmospheric window and a strong scattering ability in middle IR region by analyzing its extinction, absorption and radiation properties in IR region. Therefore, it may be used as IR absorption, extinction and radiation materials in some special fields.

  3. The association of osteopenia with levels of serum 25-hydroxyvitamin D and HOMA-IR values.

    Science.gov (United States)

    Yoldemir, T; Yavuz, D G

    2014-06-01

    To determine the association of osteopenia with levels of serum 25-hydroxyvitamin D and HOMA-IR values in postmenopausal women. Methods One hundred healthy postmenopausal women were included in a cross-sectional study. Venous blood was collected after an overnight fast and 25-hydroxyvitamin D, glucose and insulin levels were measured. HOMA-IR was calculated. Bone mineral density was measured with a dual X-ray absorptiometer. There was no difference in serum 25-hydroxyvitamin D levels and HOMA-IR values between the two groups. A weak positive correlation between serum 25-hydroxyvitamin D levels and osteopenia was detected. Insulin resistance had a weak negative association with osteopenia. The correlations between osteopenia and serum 25-hydroxyvitamin D levels and HOMA-IR values were weak among early postmenopausal women.

  4. LOCAL LUMINOUS INFRARED GALAXIES. II. ACTIVE GALACTIC NUCLEUS ACTIVITY FROM SPITZER/INFRARED SPECTROGRAPH SPECTRA

    Energy Technology Data Exchange (ETDEWEB)

    Alonso-Herrero, Almudena; Pereira-Santaella, Miguel [Centro de Astrobiologia, INTA-CSIC, E-28850 Torrejon de Ardoz, Madrid (Spain); Rieke, George H. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Rigopoulou, Dimitra [Astrophysics Department, University of Oxford, Oxford OX1 3RH (United Kingdom)

    2012-01-01

    We quantify the active galactic nucleus (AGN) contribution to the mid-infrared (mid-IR) and the total infrared (IR, 8-1000 {mu}m) emission in a complete volume-limited sample of 53 local luminous infrared galaxies (LIRGs, L{sub IR} = 10{sup 11}-10{sup 12} L{sub Sun }). We decompose the Spitzer Infrared Spectrograph low-resolution 5-38 {mu}m spectra of the LIRGs into AGN and starburst components using clumpy torus models and star-forming galaxy templates, respectively. We find that 50% (25/50) of local LIRGs have an AGN component detected with this method. There is good agreement between these AGN detections through mid-IR spectral decomposition and other AGN indicators, such as the optical spectral class, mid-IR spectral features, and X-ray properties. Taking all the AGN indicators together, the AGN detection rate in the individual nuclei of LIRGs is {approx}62%. The derived AGN bolometric luminosities are in the range L{sub bol}(AGN) = (0.4-50) Multiplication-Sign 10{sup 43} erg s{sup -1}. The AGN bolometric contribution to the IR luminosities of the galaxies is generally small, with 70% of LIRGs having L{sub bol}[AGN]/L{sub IR} {<=} 0.05. Only {approx_equal} 8% of local LIRGs have a significant AGN bolometric contribution L{sub bol}[AGN]/L{sub IR} > 0.25. From the comparison of our results with literature results of ultraluminous infrared galaxies (L{sub IR} = 10{sup 12}-10{sup 13} L{sub Sun }), we confirm that in the local universe the AGN bolometric contribution to the IR luminosity increases with the IR luminosity of the galaxy/system. If we add up the AGN bolometric luminosities we find that AGNs only account for 5%{sub -3%}{sup +8%} of the total IR luminosity produced by local LIRGs (with and without AGN detections). This proves that the bulk of the IR luminosity of local LIRGs is due to star formation activity. Taking the newly determined IR luminosity density of LIRGs in the local universe, we then estimate an AGN IR luminosity density of {Omega}{sup AGN

  5. 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.

  6. 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).

  7. Determination of the absolute concentrations of H2O - D2O mixtures using the increase in sensitivity of infra-red absorption measurements

    International Nuclear Information System (INIS)

    Ceccaldi, M.

    1964-01-01

    A description is given in this report of original work concerning an infrared method for determining the absolute isotopic content of H 2 O - D 2 O mixtures. The spectrum is obtained, in both the liquid and the solid states, of water of unknown D 2 O content and of mixtures of this water and light water. The Beer-Lambert law-is Well followed in this case; the measurement of three parameters involved in this law is described together with a method of measuring the fourth parameter. The results obtained using infrared and nuclear resonance techniques are compared. The concentration of the 99.9960 per cent reference water is known with a precision of a least + 40 ppm - 20 ppm and very likely to ± 5 ppm. (author) [fr

  8. The FUR to near-IR morphologies of luminous infrared galaxies in the goals sample

    International Nuclear Information System (INIS)

    Petty, S. M.; Armus, L.; Díaz-Santos, T.; Howell, J. H.; Surace, J. A.; Charmandaris, V.; Psychogyios, A.; Evans, A. S.; Stierwalt, S.; Floc’h, E. Le; Bridge, C.; Inami, H.

    2014-01-01

    We compare the morphologies of a sample of 20 luminous infrared galaxies (LIRGs) from the Great Observatories All-sky LIRG Survey (GOALS) in the FUV, B, I, and H bands, using the Gini (G) and M 20 parameters to quantitatively estimate the distribution and concentration of flux as a function of wavelength. Hubble Space Telescope (HST) images provide an average spatial resolution of ∼80 pc. While our LIRGs can be reliably classified as mergers across the entire range of wavelengths studied here, there is a clear shift toward more negative M 20 (more bulge-dominated) and a less significant decrease in G values at longer wavelengths. We find no correlation between the derived FUV G-M 20 parameters and the global measures of the IR to FUV flux ratio (IRX). Given the fine resolution in our HST data, this suggests either that the UV morphology and IRX are correlated on very small scales, or that the regions emitting the bulk of the IR emission emit almost no FUV light. We use our multi-wavelength data to simulate how merging LIRGs would appear from z∼0.5–3 in deep optical and near-infrared images such as the Hubble Ultra-Deep Field, and use these simulations to measure the G-M 20 at these redshifts. Our simulations indicate a noticeable decrease in G, which flattens at z⩾2 by as much as 40%, resulting in mis-classifying our LIRGs as disk-like, even in the rest-frame FUV. The higher redshift values of M 20 for the GOALS sources do not appear to change more than about 10% from the values at z∼0. The change in G-M 20 is caused by the surface brightness dimming of extended tidal features and asymmetries, and also the decreased spatial resolution which reduced the number of individual clumps identified. This effect, seen as early as z∼0.5, could easily lead to an underestimate of the number of merging galaxies at high-redshift in the rest-frame FUV.

  9. The FUV to Near-IR Morphologies of Luminous Infrared Galaxies in the Goals Sample

    Science.gov (United States)

    Petty, S. M.; Armus, L.; Charmandaris, V.; Evans, A. S.; Le Floc'h, E.; Bridge, C.; Díaz-Santos, T.; Howell, J. H.; Inami, H.; Psychogyios, A.; Stierwalt, S.; Surace, J. A.

    2014-12-01

    We compare the morphologies of a sample of 20 luminous infrared galaxies (LIRGs) from the Great Observatories All-sky LIRG Survey (GOALS) in the FUV, B, I, and H bands, using the Gini (G) and M20 parameters to quantitatively estimate the distribution and concentration of flux as a function of wavelength. Hubble Space Telescope (HST) images provide an average spatial resolution of ˜ 80 pc. While our LIRGs can be reliably classified as mergers across the entire range of wavelengths studied here, there is a clear shift toward more negative M20 (more bulge-dominated) and a less significant decrease in G values at longer wavelengths. We find no correlation between the derived FUV G-M20 parameters and the global measures of the IR to FUV flux ratio (IRX). Given the fine resolution in our HST data, this suggests either that the UV morphology and IRX are correlated on very small scales, or that the regions emitting the bulk of the IR emission emit almost no FUV light. We use our multi-wavelength data to simulate how merging LIRGs would appear from z˜ 0.5-3 in deep optical and near-infrared images such as the Hubble Ultra-Deep Field, and use these simulations to measure the G-M20 at these redshifts. Our simulations indicate a noticeable decrease in G, which flattens at z≥slant 2 by as much as 40%, resulting in mis-classifying our LIRGs as disk-like, even in the rest-frame FUV. The higher redshift values of M20 for the GOALS sources do not appear to change more than about 10% from the values at z˜ 0. The change in G-M20 is caused by the surface brightness dimming of extended tidal features and asymmetries, and also the decreased spatial resolution which reduced the number of individual clumps identified. This effect, seen as early as z˜ 0.5, could easily lead to an underestimate of the number of merging galaxies at high-redshift in the rest-frame FUV.

  10. Thermally and vibrationally induced conformational isomerizations, infrared spectra, and photochemistry of gallic acid in low-temperature matrices

    Energy Technology Data Exchange (ETDEWEB)

    Justino, Licínia L. G., E-mail: liciniaj@ci.uc.pt; Reva, Igor; Fausto, Rui [CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra (Portugal)

    2016-07-07

    Near-infrared (near-IR) narrowband selective vibrational excitation and annealing of gallic acid (3,4,5-trihydroxybenzoic acid) isolated in cryogenic matrices were used to induce interconversions between its most stable conformers. The isomerizations were probed by infrared spectroscopy. An extensive set of quantum chemical calculations, carried out at the DFT(B3LYP)/6-311++G(d,p) level of approximation, was used to undertake a detailed analysis of the ground state potential energy surface of the molecule. This investigation of the molecule conformational space allowed extracting mechanistic insights into the observed annealing- or near-IR-induced isomerization processes. The infrared spectra of the two most stable conformers of gallic acid in N{sub 2}, Xe, and Ar matrices were fully assigned. Finally, the UV-induced photochemistry of the matrix isolated compound was investigated.

  11. Thermally and vibrationally induced conformational isomerizations, infrared spectra, and photochemistry of gallic acid in low-temperature matrices

    Science.gov (United States)

    Justino, Licínia L. G.; Reva, Igor; Fausto, Rui

    2016-07-01

    Near-infrared (near-IR) narrowband selective vibrational excitation and annealing of gallic acid (3,4,5-trihydroxybenzoic acid) isolated in cryogenic matrices were used to induce interconversions between its most stable conformers. The isomerizations were probed by infrared spectroscopy. An extensive set of quantum chemical calculations, carried out at the DFT(B3LYP)/6-311++G(d,p) level of approximation, was used to undertake a detailed analysis of the ground state potential energy surface of the molecule. This investigation of the molecule conformational space allowed extracting mechanistic insights into the observed annealing- or near-IR-induced isomerization processes. The infrared spectra of the two most stable conformers of gallic acid in N2, Xe, and Ar matrices were fully assigned. Finally, the UV-induced photochemistry of the matrix isolated compound was investigated.

  12. Thermally and vibrationally induced conformational isomerizations, infrared spectra, and photochemistry of gallic acid in low-temperature matrices

    International Nuclear Information System (INIS)

    Justino, Licínia L. G.; Reva, Igor; Fausto, Rui

    2016-01-01

    Near-infrared (near-IR) narrowband selective vibrational excitation and annealing of gallic acid (3,4,5-trihydroxybenzoic acid) isolated in cryogenic matrices were used to induce interconversions between its most stable conformers. The isomerizations were probed by infrared spectroscopy. An extensive set of quantum chemical calculations, carried out at the DFT(B3LYP)/6-311++G(d,p) level of approximation, was used to undertake a detailed analysis of the ground state potential energy surface of the molecule. This investigation of the molecule conformational space allowed extracting mechanistic insights into the observed annealing- or near-IR-induced isomerization processes. The infrared spectra of the two most stable conformers of gallic acid in N 2 , Xe, and Ar matrices were fully assigned. Finally, the UV-induced photochemistry of the matrix isolated compound was investigated.

  13. Raman and Fourier Transform Infrared (FT-IR) Mineral to Matrix Ratios Correlate with Physical Chemical Properties of Model Compounds and Native Bone Tissue.

    Science.gov (United States)

    Taylor, Erik A; Lloyd, Ashley A; Salazar-Lara, Carolina; Donnelly, Eve

    2017-10-01

    Raman and Fourier transform infrared (FT-IR) spectroscopic imaging techniques can be used to characterize bone composition. In this study, our objective was to validate the Raman mineral:matrix ratios (ν 1 PO 4 :amide III, ν 1 PO 4 :amide I, ν 1 PO 4 :Proline + hydroxyproline, ν 1 PO 4 :Phenylalanine, ν 1 PO 4 :δ CH 2 peak area ratios) by correlating them to ash fraction and the IR mineral:matrix ratio (ν 3 PO 4 :amide I peak area ratio) in chemical standards and native bone tissue. Chemical standards consisting of varying ratios of synthetic hydroxyapatite (HA) and collagen, as well as bone tissue from humans, sheep, and mice, were characterized with confocal Raman spectroscopy and FT-IR spectroscopy and gravimetric analysis. Raman and IR mineral:matrix ratio values from chemical standards increased reciprocally with ash fraction (Raman ν 1 PO 4 /Amide III: P Raman ν 1 PO 4 /Amide I: P Raman ν 1 PO 4 /Proline + Hydroxyproline: P Raman ν 1 PO 4 /Phenylalanine: P Raman ν 1 PO 4 /δ CH 2 : P Raman and IR mineral:matrix ratio values were strongly correlated ( P Raman mineral:matrix bone composition parameter correlates strongly to ash fraction and to its IR counterpart. Finally, the mineral:matrix ratio values of the native bone tissue are similar to those of both chemical standards and theoretical values, confirming the biological relevance of the chemical standards and the characterization techniques.

  14. 3D FT-IR imaging spectroscopy of phase-separation in a poly(3-hydroxybutyrate)/poly(L-lactic acid) blend

    Science.gov (United States)

    Miriam Unger; Julia Sedlmair; Heinz W. Siesler; Carol Hirschmugl; Barbara Illman

    2014-01-01

    In the present study, 3D FT-IR spectroscopic imaging measurements were applied to study the phase separation of a poly(3-hydroxybutyrate) (PHB)/poly(L-lactic acid) (PLA) (50:50 wt.%) polymer blend film. While in 2D projection imaging the z-dependent information is overlapped, thereby complicating the analysis, FT-IR spectro-micro-tomography,...

  15. Vibrational spectroscopy investigation using ab initio and density functional theory analysis on the structure of 3-(6-benzoyl-2-oxobenzo[ d]oxazol-3(2 H)-yl)propanoic acid

    Science.gov (United States)

    Arslan, Hakan; Algül, Öztekin; Önkol, Tijen

    2008-08-01

    The molecular structure, vibrational frequencies and infrared intensities of the 3-(6-benzoyl-2-oxobenzo[ d]oxazol-3(2 H)-yl)propanoic acid were calculated by the HF and DFT methods using 6-31G(d) basis set. The FT-infrared spectra have been measured for the title compound in the solid state. We obtained 11 stable conformers for the title compound, however the Conformer 1 is approximately 3.88 kcal/mol more stable than the Conformer 11. The comparison of the theoretical and experimental geometry of the title compound shows that the X-ray parameters fairly well reproduce the geometry of the Conformer 1. The harmonic vibrations computed of this compound by the B3LYP/6-31G(d) method are in a good agreement with the observed IR spectral data. Theoretical vibrational spectra of the title compound were interpreted by means of PEDs using VEDA 4 program.

  16. Binding water to a PEG-linked flexible bichromophore: IR spectra of diphenoxyethane-(H{sub 2}O){sub n} clusters, n = 2-4

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Patrick S.; Buchanan, Evan G.; Gord, Joseph R.; Zwier, Timothy S., E-mail: zwier@purdue.edu [Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084 (United States)

    2015-04-21

    The single-conformation infrared (IR) and ultraviolet (UV) spectroscopies of neutral 1,2-diphenoxyethane-(H{sub 2}O){sub n} clusters with n = 2-4 (labeled henceforth as 1:n) have been studied in a molecular beam using a combination of resonant two-photon ionization, IR-UV holeburning, and resonant ion-dip infrared (RIDIR) spectroscopies. Ground state RIDIR spectra in the OH and CH stretch regions were used to provide firm assignments for the structures of the clusters by comparing the experimental spectra with the predictions of calculations carried out at the density functional M05-2X/6-31+G(d) level of theory. At all sizes in this range, the water molecules form water clusters in which all water molecules engage in a single H-bonded network. Selective binding to the tgt monomer conformer of 1,2-diphenoxyethane (C{sub 6}H{sub 5}-O-CH{sub 2}-CH{sub 2}-O-C{sub 6}H{sub 5}, DPOE) occurs, since this conformer provides a binding pocket in which the two ether oxygens and two phenyl ring π clouds can be involved in stabilizing the water cluster. The 1:2 cluster incorporates a water dimer “chain” bound to DPOE much as it is in the 1:1 complex [E. G. Buchanan et al., J. Phys. Chem. Lett. 4, 1644 (2013)], with primary attachment via a double-donor water that bridges the ether oxygen of one phenoxy group and the π cloud of the other. Two conformers of the 1:3 cluster are observed and characterized, one that extends the water chain to a third molecule (1:3 chain) and the other incorporating a water trimer cycle (1:3 cycle). A cyclic water structure is also observed for the 1:4 cluster. These structural characterizations provide a necessary foundation for studies of the perturbations imposed on the two close-lying S{sub 1}/S{sub 2} excited states of DPOE considered in the adjoining paper [P. S. Walsh et al., J. Chem. Phys. 142, 154304 (2015)].

  17. [Study on the identification of six kinds of bee pollens by three-step infrared macro-fingerprint method].

    Science.gov (United States)

    Wu, Jie; Zhou, Quno; Wu, Li-Ming; Au, Jian-Dong; Sun, Su-Qin; Hu, Fu-Liang

    2010-02-01

    Six kinds of bee pollens, including apricot pollen, lotus pollen, rape pollen, camellia pollen, watermelon pollen and corn poppy pollen, were identified non-destructively by Fourier transform infrared spectroscopy (FTIR) combined with derivative spectra and two-dimensional correlation spectroscopy (2D) in the present article. Compared with conventional IR spectra of samples, some certain differences were found in the characteristic peaks of proteins, lipids and carbohydrates. Obvious differences of the six kinds of bee pollens were found in the second derivative spectra. And in the 2D-IR correlation spectra, the samples presented the differences in the position and intensity of the autopeaks and correlation peak clusters. Therefore, the three-step IR macro-fingerprint provides a more rapid and effective method for the identification of different kinds of bee pollens.

  18. Reactions of laser-ablated Co, Rh, and Ir with CO: Infrared spectra and density functional calculations of the metal carbonyl molecules, cations and anions in solid neon

    International Nuclear Information System (INIS)

    Zhou, M.; Andrews, L.

    1999-01-01

    Laser ablation produces metal atoms, cations, and electrons for reaction with CO during condensation in excess neon at 4 K. Infrared spectra are observed for the metal carbonyls, cations, and anions, which are identified from isotopic shifts ( 13 CO, C 18 O) and splittings using mixed isotopic precursors. Density functional calculations with pseudopotentials for Rh and Ir predict the observed carbonyl stretching frequencies within 1--2%. This characterization of the simple RhCO + , RhCO, and RhCO - (and Ir) species over a 350 cm -1 range provides a scale for comparison of larger catalytically active Rh and Ir carbonyl complexes in solution and on surfaces to estimate charge on the metal center. This work provides the first spectroscopic characterization of Rh and Ir carbonyl cations and anions except for the stable tetracarbonyl anions in solution

  19. FT-IR spectroscopic analyses of 2-(2-furanylmethylene) propanedinitrile

    Science.gov (United States)

    Soliman, H. S.; Eid, Kh. M.; Ali, H. A. M.; El-Mansy, M. A. M.; Atef, S. M.

    2013-03-01

    In the present work, a computational study for the optimized molecular structural parameters, thermo-chemical parameters, total dipole moment, HOMO-LUMO energy gap and a combined experimental and computational study for FT-IR spectra for 2-(2-furanylmethylene) propanedinitrile have been investigated using B3LYP utilizing 6-31G and 6-311G basis set. Our calculated results showed that the investigated compound possesses a dipole moment of 7.5 D and HOMO-LUMO energy gap of 3.92 eV using B3LYP/6-311G which indicates that our investigated compound is highly applicable for photovoltaic solar cell applications.

  20. Anisotropic Magnetoresistance in Antiferromagnetic Sr_{2}IrO_{4}

    Directory of Open Access Journals (Sweden)

    C. Wang

    2014-11-01

    Full Text Available We report point-contact measurements of anisotropic magnetoresistance (AMR in a single crystal of antiferromagnetic Mott insulator Sr_{2}IrO_{4}. The point-contact technique is used here as a local probe of magnetotransport properties on the nanoscale. The measurements at liquid nitrogen temperature reveal negative magnetoresistances (up to 28% for modest magnetic fields (250 mT applied within the IrO_{2} a-b plane and electric currents flowing perpendicular to the plane. The angular dependence of magnetoresistance shows a crossover from fourfold to twofold symmetry in response to an increasing magnetic field with angular variations in resistance from 1% to 14%. We tentatively attribute the fourfold symmetry to the crystalline component of AMR and the field-induced transition to the effects of applied field on the canting of antiferromagnetic-coupled moments in Sr_{2}IrO_{4}. The observed AMR is very large compared to the crystalline AMRs in 3d transition metal alloys or oxides (0.1%–0.5% and can be associated with the large spin-orbit interactions in this 5d oxide while the transition provides evidence of correlations between electronic transport, magnetic order, and orbital states. The finding of this work opens an entirely new avenue to not only gain a new insight into physics associated with spin-orbit coupling but also to better harness the power of spintronics in a more technically favorable fashion.

  1. Rovibrational study of the 2ν2 band of D213CO by high-resolution Fourier transform infrared spectroscopy

    Science.gov (United States)

    Wu, Q. Y.; Tan, T. L.; A'dawiah, Rabia'tul; Ng, L. L.

    2018-03-01

    The high-resolution FTIR spectrum of the 2ν2 band (3250-3380 cm-1) of D213CO was recorded at an unapodized resolution of 0.0063 cm-1. A total of 747 rovibrational transitions have been assigned and fitted up to J″ = 32 and Ka″ = 10 using the Watson's A-reduced Hamiltonian in the Ir representation. A set of accurate upper state (v2 = 2) rovibrational constants, three rotational and five quartic centrifugal distortion constants, were determined for the first time. The band center of the 2ν2 band was found to be 3326.765109 ± 0.000079 cm-1. The rms deviation of the rovibrational fit was 0.00096 cm-1.

  2. FIRST INFRARED BAND STRENGTHS FOR AMORPHOUS CO{sub 2}, AN OVERLOOKED COMPONENT OF INTERSTELLAR ICES

    Energy Technology Data Exchange (ETDEWEB)

    Gerakines, Perry A.; Hudson, Reggie L., E-mail: Reggie.Hudson@NASA.gov [Astrochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2015-08-01

    Solid carbon dioxide (CO{sub 2}) has long been recognized as a component of both interstellar and solar system ices, but a recent literature search has revealed significant qualitative and quantitative discrepancies in the laboratory spectra on which the abundances of extraterrestrial CO{sub 2} are based. Here we report new infrared (IR) spectra of amorphous CO{sub 2}-ice along with band intensities (band strengths) of four mid-IR absorptions, the first such results in the literature. A possible thickness dependence for amorphous-CO{sub 2} IR band shapes and positions also is investigated, and the three discordant reports of amorphous CO{sub 2} spectra in the literature are addressed. Applications of our results are discussed with an emphasis on laboratory investigations and results from astronomical observations. A careful comparison with earlier work shows that the IR spectra calculated from several databases for CO{sub 2} ices, all ices being made near 10 K, are not for amorphous CO{sub 2}, but rather for crystalline CO{sub 2} or crystalline-amorphous mixtures.

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

    Science.gov (United States)

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

    2016-04-01

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

  4. UNTANGLING THE NEAR-IR SPECTRAL FEATURES IN THE PROTOPLANETARY ENVIRONMENT OF KH 15D

    Energy Technology Data Exchange (ETDEWEB)

    Arulanantham, Nicole A.; Herbst, William; Gilmore, Martha S.; Cauley, P. Wilson [Astronomy Department, Wesleyan University, Middletown, CT 06459 (United States); Leggett, S. K., E-mail: nicole.arulanantham@colorado.edu [Gemini Observatory (North), Hilo, HI 96720 (United States)

    2017-01-10

    We report on Gemini/GNIRS observations of the binary T Tauri system V582 Mon (KH 15D) at three orbital phases. These spectra allow us to untangle five components of the system: the photosphere and magnetosphere of star B, the jet, scattering properties of the ring material, and excess near-infrared (near-IR) radiation previously attributed to a possible self-luminous planet. We confirm an early-K subgiant classification for star B and show that the magnetospheric He i emission line is variable, possibly indicating increased mass accretion at certain times. As expected, the H{sub 2} emission features associated with the inner part of the jet show no variation with orbital phase. We show that the reflectance spectrum for the scattered light has a distinctive blue slope and spectral features consistent with scattering and absorption by a mixture of water and methane ice grains in the 1–50 μ m size range. This suggests that the methane frost line is closer than ∼5 au in this system, requiring that the grains be shielded from direct radiation. After correcting for features from the scattered light, jet, magnetosphere, and photosphere, we confirm the presence of leftover near-IR light from an additional source, detectable near minimum brightness. A spectral emission feature matching the model spectrum of a 10 M {sub J}, 1 Myr old planet is found in the excess flux, but other expected features from this model are not seen. Our observations, therefore, tentatively support the picture that a luminous planet is present within the system, although they cannot yet be considered definitive.

  5. NEAR-INFRARED IMAGING OF THE STAR-FORMING REGIONS SH2-157 AND SH2-152

    International Nuclear Information System (INIS)

    Chen Yafeng; Yang Ji; Zeng Qin; Yao Yongqiang; Sato, Shuji

    2009-01-01

    Near-infrared JHK' and H 2 v = 1-0 S (1) imaging observations of the star-forming regions Sh2-157 and Sh2-152 are presented. The data reveal a cluster of young stars associated with H 2 line emission in each region. Additionally, many IR point sources are found in the dense core of each molecular cloud. Most of these sources exhibit infrared color excesses typical of T Tauri stars, Herbig Ae/Be stars, and protostars. Several display the characteristics of massive stars. We calculate histograms of the K'-magnitude and [H - K'] color for all sources, as well as two-color and color-magnitude diagrams. The stellar populations inside and outside the clusters are similar, suggesting that these systems are rather evolved. Shock-driven H 2 emission knots are also detected, which may be related to evident subclusters in an earlier evolutionary stage.

  6. Applications of FT-IR spectrophotometry in cancer diagnostics.

    Science.gov (United States)

    Bunaciu, Andrei A; Hoang, Vu Dang; Aboul-Enein, Hassan Y

    2015-01-01

    This review provides a brief background to the application of infrared spectroscopy, including Fourier transform-infrared spectroscopy, in biological fluids. It is not meant to be complete or exhaustive but to provide the reader with sufficient background for selected applications in cancer diagnostics. Fourier transform-infrared spectroscopy (FT-IR) is a fast and nondestructive analytical method. The infrared spectrum of a mixture serves as the basis to quantitate its constituents, and a number of common clinical chemistry tests have proven to be feasible using this approach. This review focuses on biomedical FT-IR applications, published in the period 2009-2013, used for early detection of cancer through qualitative and quantitative analysis.

  7. Optical Determination of Lead Chrome Green in Green Tea by Fourier Transform Infrared (FT-IR Transmission Spectroscopy.

    Directory of Open Access Journals (Sweden)

    Xiaoli Li

    Full Text Available The potential of Fourier transform infrared (FT-IR transmission spectroscopy for determination of lead chrome green in green tea was investigated based on chemometric methods. Firstly, the qualitative analysis of lead chrome green in tea was performed based on partial least squares discriminant analysis (PLS-DA, and the correct rate of classification was 100%. And then, a hybrid method of interval partial least squares (iPLS regression and successive projections algorithm (SPA was proposed to select characteristic wavenumbers for the quantitative analysis of lead chrome green in green tea, and 19 wavenumbers were obtained finally. Among these wavenumbers, 1384 (C = C, 1456, 1438, 1419(C = N, and 1506 (CNH cm-1 were the characteristic wavenumbers of lead chrome green. Then, these 19 wavenumbers were used to build determination models. The best model was achieved by least squares support vector machine (LS-SVMalgorithm with high coefficient of determination and low root-mean square error of prediction set (R2p = 0.864 and RMSEP = 0.291. All these results indicated the feasibility of IR spectra for detecting lead chrome green in green tea.

  8. Protonation of benzimidazoles and 1,2,3-benzotriazoles Solid-state linear dichroic infrared (IR-LD) spectral analysis and ab initio calculations

    Science.gov (United States)

    Ivanova, Bojidarka B.; Pindeva, Liliya I.

    2006-09-01

    IR-LD spectroscopic data obtained by the orientated solid samples as a suspension in a nematic liquid crystal of 1-hydroxy-1,2,3-benzotriazole, 2-methyl-, 2-acetonitrilebenzimidazoles and their protonated salts have been presented. The stereo-structures have been predicted and compared with theoretical ones. The IR-characteristic bands assignments of all molecule systems have been achieved.

  9. Hydrogenated fullerenes in space: FT-IR spectra analysis

    Energy Technology Data Exchange (ETDEWEB)

    El-Barbary, A. A. [Physics Department, Faculty of Education, Ain-Shams University, Cairo, Egypt Physics Department, Faculty of Science, Jazan University, Jazan (Saudi Arabia)

    2016-06-10

    Fullerenes and hydrogenated fullerenes are found in circumstellar and interstellar environments. But the determination structures for the detected bands in the interstellar and circumstellar space are not completely understood so far. For that purpose, the aim of this article is to provide all possible infrared spectra for C{sub 20} and C{sub 60} fullerenes and their hydrogenated fullerenes. Density Functional theory (DFT) is applied using B3LYP exchange-functional with basis set 6–31G(d, p). The Fourier transform infrared spectroscopy (FT-IR) is found to be capable of distinguishing between fullerenes, mono hydrogenated fullerenes and fully hydrogenated fullerenes. In addition, deposition of one hydrogen atom outside the fully hydrogenated fullerenes is found to be distinguished by forming H{sub 2} molecule at peak around 4440 cm{sup −1}. However, deposition of one hydrogen atom inside the fully hydrogenated fullerenes cannot be distinguished. The obtained spectral structures are analyzed and are compared with available experimental results.

  10. Hydrogenated fullerenes in space: FT-IR spectra analysis

    International Nuclear Information System (INIS)

    El-Barbary, A. A.

    2016-01-01

    Fullerenes and hydrogenated fullerenes are found in circumstellar and interstellar environments. But the determination structures for the detected bands in the interstellar and circumstellar space are not completely understood so far. For that purpose, the aim of this article is to provide all possible infrared spectra for C 20 and C 60 fullerenes and their hydrogenated fullerenes. Density Functional theory (DFT) is applied using B3LYP exchange-functional with basis set 6–31G(d, p). The Fourier transform infrared spectroscopy (FT-IR) is found to be capable of distinguishing between fullerenes, mono hydrogenated fullerenes and fully hydrogenated fullerenes. In addition, deposition of one hydrogen atom outside the fully hydrogenated fullerenes is found to be distinguished by forming H 2 molecule at peak around 4440 cm −1 . However, deposition of one hydrogen atom inside the fully hydrogenated fullerenes cannot be distinguished. The obtained spectral structures are analyzed and are compared with available experimental results.

  11. Radioluminescence dating: the IR emission of feldspar

    International Nuclear Information System (INIS)

    Schilles, Thomas.; Habermann, Jan

    2000-01-01

    A new luminescence reader for radioluminescence (RL) measurements is presented. The system allows detection of RL emissions in the near infrared region (IR). Basic bleaching properties of the IR-RL emission of feldspars are investigated. Sunlight-bleaching experiments as a test for sensitivity changes are presented. IR-bleaching experiments were carried out to obtain information about the underlying physical processes of the IR-RL emission

  12. Infrared technology XVI; Proceedings of the Meeting, San Diego, CA, July 11-13, 1990

    International Nuclear Information System (INIS)

    Spiro, I.J.

    1990-01-01

    Various papers in infrared technology are presented. Individual topics addressed include: Field Observations and Measurement Experiment, GaAs/AlGAs multiquantum-well IR detectors, 256 x 256 PtSi hybrid array for astronomy applications, compact 128 InSb focal plane assembly for thermal imaging, statistical analysis of thermal images generated by line scanning, performance comparison of platinum silicide cameras, atmospheric applications of IR heterodyne laser detection, French activity in IR astronomy from stratospheric balloons, advances in IR technology at Paris Observatory, far-IR photoconductors, applications of IR bidimensional devices in astronomy, far-IR transmission spectra of YBa2Cu3O(7-d) thin films. Also considered are: far-IR multiple-path cell without internal mirrors, optical properties of solid-state laser-type materials in the near-IR, SOFRADIR IR focal plane array production, recent developments on Isocam long-wavelength channel detector, 128 x 128 3-5 micron focal plane arrays at 77-K and 200-K operation, digital test target for display evaluation, IR radiation from rocket plumes, 128 x 128 InGaAs detector array for 1.0-1.7 micron

  13. Symmetry-improved 2PI approach to the Goldstone-boson IR problem of the SM effective potential

    Directory of Open Access Journals (Sweden)

    Apostolos Pilaftsis

    2016-05-01

    Full Text Available The effective potential of the Standard Model (SM, from three loop order and higher, suffers from infrared (IR divergences arising from quantum effects due to massless would-be Goldstone bosons associated with the longitudinal polarizations of the W± and Z bosons. Such IR pathologies also hinder accurate evaluation of the two-loop threshold corrections to electroweak quantities, such as the vacuum expectation value of the Higgs field. However, these divergences are an artifact of perturbation theory, and therefore need to be consistently resummed in order to obtain an IR-safe effective potential. The so-called Two-Particle-Irreducible (2PI effective action provides a rigorous framework to consistently perform such resummations, without the need to resort to ad hoc subtractions or running into the risk of over-counting contributions. By considering the recently proposed symmetry-improved 2PI formalism, we address the problem of the Goldstone-boson IR divergences of the SM effective potential in the gaugeless limit of the theory. In the same limit, we evaluate the IR-safe symmetry-improved 2PI effective potential, after taking into account quantum loops of chiral fermions, as well as the renormalization of spurious custodially breaking effects triggered by fermionic Yukawa interactions. Finally, we compare our results with those obtained with other methods presented in the literature.

  14. An FT-Raman, FT-IR, and Quantum Chemical Investigation of Stanozolol and Oxandrolone

    Directory of Open Access Journals (Sweden)

    Tibebe Lemma

    2017-12-01

    Full Text Available We have studied the Fourier Transform Infrared (FT-IR and the Fourier transform Raman (FT-Raman spectra of stanozolol and oxandrolone, and we have performed quantum chemical calculations based on the density functional theory (DFT with a B3LYP/6-31G (d, p level of theory. The FT-IR and FT-Raman spectra were collected in a solid phase. The consistency between the calculated and experimental FT-IR and FT-Raman data indicates that the B3LYP/6-31G (d, p can generate reliable geometry and related properties of the title compounds. Selected experimental bands were assigned and characterized on the basis of the scaled theoretical wavenumbers by their total energy distribution. The good agreement between the experimental and theoretical spectra allowed positive assignment of the observed vibrational absorption bands. Finally, the calculation results were applied to simulate the Raman and IR spectra of the title compounds, which show agreement with the observed spectra.

  15. FT-Raman, FT-IR spectra and total energy distribution of 3-pentyl-2,6-diphenylpiperidin-4-one: DFT method.

    Science.gov (United States)

    Subashchandrabose, S; Saleem, H; Erdogdu, Y; Rajarajan, G; Thanikachalam, V

    2011-11-01

    FT-Raman and FT-IR spectra were recorded for 3-pentyl-2,6-diphenylpiperidin-4-one (PDPO) sample in solid state. The equilibrium geometries, harmonic vibrational frequencies, infrared and the Raman scattering intensities were computed using DFT/6-31G(d,p) level. Results obtained at this level of theory were used for a detailed interpretation of the infrared and Raman spectra, based on the total energy distribution (TED) of the normal modes. Molecular parameters such as bond lengths, bond angles and dihedral angles were calculated and compared with X-ray diffraction data. This comparison was good agreement. The intra-molecular charge transfer was calculated by means of natural bond orbital analysis (NBO). Hyperconjugative interaction energy was more during the π-π* transition. Energy gap of the molecule was found using HOMO and LUMO calculation, hence the less band gap, which seems to be more stable. Atomic charges of the carbon, nitrogen and oxygen were calculated using same level of calculation. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Analysis of the development of missile-borne IR imaging detecting technologies

    Science.gov (United States)

    Fan, Jinxiang; Wang, Feng

    2017-10-01

    Today's infrared imaging guiding missiles are facing many challenges. With the development of targets' stealth, new-style IR countermeasures and penetrating technologies as well as the complexity of the operational environments, infrared imaging guiding missiles must meet the higher requirements of efficient target detection, capability of anti-interference and anti-jamming and the operational adaptability in complex, dynamic operating environments. Missileborne infrared imaging detecting systems are constrained by practical considerations like cost, size, weight and power (SWaP), and lifecycle requirements. Future-generation infrared imaging guiding missiles need to be resilient to changing operating environments and capable of doing more with fewer resources. Advanced IR imaging detecting and information exploring technologies are the key technologies that affect the future direction of IR imaging guidance missiles. Infrared imaging detecting and information exploring technologies research will support the development of more robust and efficient missile-borne infrared imaging detecting systems. Novelty IR imaging technologies, such as Infrared adaptive spectral imaging, are the key to effectively detect, recognize and track target under the complicated operating and countermeasures environments. Innovative information exploring techniques for the information of target, background and countermeasures provided by the detection system is the base for missile to recognize target and counter interference, jamming and countermeasure. Modular hardware and software development is the enabler for implementing multi-purpose, multi-function solutions. Uncooled IRFPA detectors and High-operating temperature IRFPA detectors as well as commercial-off-the-shelf (COTS) technology will support the implementing of low-cost infrared imaging guiding missiles. In this paper, the current status and features of missile-borne IR imaging detecting technologies are summarized. The key

  17. Near-infrared sources in the molecular cloud G35.2-0.74

    International Nuclear Information System (INIS)

    Tapia, M.; Roth, M.; Persi, P.; Ferrari-Toniolo, M.

    1985-01-01

    Near-infrared (1-4 μm) observations of the molecular cloud G35.2-0.74 reveal the presence of four infrared sources in the vicinity of two previously reported centres of recent star formation. The northern part of G35.2-0.74 contains three point sources which are interpreted as highly obscured stars. Irs 1 coincides with H 2 O and OH maser sources and seems to be a very young early-type star. The southern part of G35.2-0.74 shows a diffuse 2.2-μm source with a flux distribution in the short-wavelength region compatible with free-free emission and a large excess at lambda > or approx. 3 μm attributed to warm dust mixed with the gas. These data are consistent with a fully developed HII region. (author)

  18. Classification and structural analysis of live and dead salmonella cells using fourier transform infrared (FT-IR) spectroscopy and principle component analysis (PCA)

    Science.gov (United States)

    Fourier Transform Infrared Spectroscopy (FT-IR) was used to detect Salmonella typhimurium and Salmonella enteritidis foodborne bacteria and distinguish between live and dead cells of both serotypes. Bacteria were loaded individually on the ZnSe Attenuated Total Reflection (ATR) crystal surface and s...

  19. Optical and IR light curves of VV Puppis

    International Nuclear Information System (INIS)

    Szkody, P.; Bailey, J.A.; Hough, J.H.

    1983-01-01

    We present optical (0.36 to 0.6 μm) light curves with time resolutions of seconds and infrared (IR) (1.25 to 2.2 μm) light curves with time resolutions of minutes for VV Puppis during a high state. The optical light curves show a single hump with largest amplitude in the V filter, while the IR light curves show a double hump sinusoidal variation. Flickering is evident in both the optical and IR light curves, with the largest amplitude in optical B light. Through subtraction of the low state fluxes from our high state values, we obtain a flux distribution of the accretion column which peaks at 0.55 μm and becomes #betta# 2 in the IR, consistent with current cyclotron models. Comparison of the observed IR variations throughout the orbit with the expected variations due to an M4 star heated by an accretion column at an inclination of 66 0 suggests that the IR light is a combination of the secondary star plus contributions from two emitting poles. (author)

  20. IR + VUV double resonance spectroscopy and extended density functional theory studies of ketone solvation by alcohol: 2-butanone·(methanol)n, n = 1-4 clusters.

    Science.gov (United States)

    Shin, Joong-Won; Bernstein, Elliot R

    2017-09-28

    Infrared plus vacuum ultraviolet (IR + VUV) photoionization vibrational spectroscopy of 2-butanone/methanol clusters [MEK·(MeOH) n , n = 1-4] is performed to explore structures associated with hydrogen bonding of MeOH molecules to the carbonyl functional group of the ketone. IR spectra and X3LYP/6-31++G(d,p) calculations show that multiple isomers of MEK·(MeOH) n are generated in the molecular beam as a result of several hydrogen bonding sites available to the clusters throughout the size range investigated. Isomer interconversion involving solvating MeOH rearrangement should probably occur for n = 1 and 2. The mode energy for a hydrogen bonded OH stretching transition gradually redshifts as the cluster size increases. Calculations suggest that the n = 3 cluster isomers adopt structures in which the MEK molecule is inserted into the cyclic MeOH hydrogen bond network. In larger structures, the cyclic network may be preserved.

  1. X-ray diffraction, inelastic neutron scattering (INS) and infrared (IR) studies on 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex

    Energy Technology Data Exchange (ETDEWEB)

    Pawlukojc, A. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Sawka-Dobrowolska, W. [Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw (Poland); Bator, G. [Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw (Poland); Sobczyk, L. [Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw (Poland)], E-mail: sobczyk@chem.uni.wroc.pl; Grech, E. [Institute of Chemistry and Environmental Protection, Szczecin University of Technology, Piastow Al. 12, 71-065 Szczecin (Poland); Nowicka-Scheibe, J. [Institute of Chemistry and Environmental Protection, Szczecin University of Technology, Piastow Al. 12, 71-065 Szczecin (Poland)

    2006-09-11

    The structure of the 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex was determined at 100 K. In the crystalline lattice the molecules of HMB (D) and TCNE (A) are arranged in DDADDADD stacks along the b-axis. Based on the red shift of the {nu}(C{identical_to}N) IR frequencies the charge transfer (CT) degree (Z) was estimated to be equal to 0.14. It is markedly higher than that for the complex of HMB with tetracyanoquinodimethane (TCNQ) for which Z = 0.06. The analysis of vibrational modes connected with torsional motion in the low frequency region was performed based on the inelastic neutron scattering (INS) experiments and DFT theoretical calculations. The correlation between {nu} {sub exp}/{nu} {sub calc} and {nu} {sub calc} shows a deviation of experimental values from calculated ones. It is the higher the lower is the frequency of the analysed mode. The comparison of correlations for neat HMB and its complexes with TCNQ and TCNE suggests that some role in decreasing the barrier to rotation can be played by the charge transfer between D and A molecules.

  2. X-ray diffraction, inelastic neutron scattering (INS) and infrared (IR) studies on 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex

    International Nuclear Information System (INIS)

    Pawlukojc, A.; Sawka-Dobrowolska, W.; Bator, G.; Sobczyk, L.; Grech, E.; Nowicka-Scheibe, J.

    2006-01-01

    The structure of the 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex was determined at 100 K. In the crystalline lattice the molecules of HMB (D) and TCNE (A) are arranged in DDADDADD stacks along the b-axis. Based on the red shift of the ν(C≡N) IR frequencies the charge transfer (CT) degree (Z) was estimated to be equal to 0.14. It is markedly higher than that for the complex of HMB with tetracyanoquinodimethane (TCNQ) for which Z = 0.06. The analysis of vibrational modes connected with torsional motion in the low frequency region was performed based on the inelastic neutron scattering (INS) experiments and DFT theoretical calculations. The correlation between ν exp /ν calc and ν calc shows a deviation of experimental values from calculated ones. It is the higher the lower is the frequency of the analysed mode. The comparison of correlations for neat HMB and its complexes with TCNQ and TCNE suggests that some role in decreasing the barrier to rotation can be played by the charge transfer between D and A molecules

  3. X-ray diffraction, inelastic neutron scattering (INS) and infrared (IR) studies on 2:1 hexamethylbenzene (HMB) tetracyanoethylene (TCNE) complex

    Science.gov (United States)

    Pawlukojć, A.; Sawka-Dobrowolska, W.; Bator, G.; Sobczyk, L.; Grech, E.; Nowicka-Scheibe, J.

    2006-09-01

    The structure of the 2:1 hexamethylbenzene (HMB)-tetracyanoethylene (TCNE) complex was determined at 100 K. In the crystalline lattice the molecules of HMB (D) and TCNE (A) are arranged in DDADDADD stacks along the b-axis. Based on the red shift of the ν(C tbnd N) IR frequencies the charge transfer (CT) degree ( Z) was estimated to be equal to 0.14. It is markedly higher than that for the complex of HMB with tetracyanoquinodimethane (TCNQ) for which Z = 0.06. The analysis of vibrational modes connected with torsional motion in the low frequency region was performed based on the inelastic neutron scattering (INS) experiments and DFT theoretical calculations. The correlation between νexp/ νcalc and νcalc shows a deviation of experimental values from calculated ones. It is the higher the lower is the frequency of the analysed mode. The comparison of correlations for neat HMB and its complexes with TCNQ and TCNE suggests that some role in decreasing the barrier to rotation can be played by the charge transfer between D and A molecules.

  4. 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

  5. Single-nucleotide polymorphism of INS, INSR, IRS1, IRS2, PPAR-G ...

    Indian Academy of Sciences (India)

    2017-03-02

    Mar 2, 2017 ... Abstract. Polycystic ovary syndrome (PCOS) is the most common and a complex female endocrine disorder, and is one of the leading cause of female infertility. Here, we aimed to investigate the association of single-nucleotide polymorphism of INS, INSR,. IRS1, IRS2, PPAR-G and CAPN10 gene in the ...

  6. Inhibition of PTP1B Restores IRS1-Mediated Hepatic Insulin Signaling in IRS2-Deficient Mice

    Science.gov (United States)

    González-Rodríguez, Águeda; Gutierrez, Jose A. Mas; Sanz-González, Silvia; Ros, Manuel; Burks, Deborah J.; Valverde, Ángela M.

    2010-01-01

    OBJECTIVE Mice with complete deletion of insulin receptor substrate 2 (IRS2) develop hyperglycemia, impaired hepatic insulin signaling, and elevated gluconeogenesis, whereas mice deficient for protein tyrosine phosphatase (PTP)1B display an opposing hepatic phenotype characterized by increased sensitivity to insulin. To define the relationship between these two signaling pathways in the regulation of liver metabolism, we used genetic and pharmacological approaches to study the effects of inhibiting PTP1B on hepatic insulin signaling and expression of gluconeogenic enzymes in IRS2−/− mice. RESEARCH DESIGN AND METHODS We analyzed glucose homeostasis and insulin signaling in liver and isolated hepatocytes from IRS2−/− and IRS2−/−/PTP1B−/− mice. Additionally, hepatic insulin signaling was assessed in control and IRS2−/− mice treated with resveratrol, an antioxidant present in red wine. RESULTS In livers of hyperglycemic IRS2−/− mice, the expression levels of PTP1B and its association with the insulin receptor (IR) were increased. The absence of PTP1B in the double-mutant mice restored hepatic IRS1-mediated phosphatidylinositol (PI) 3-kinase/Akt/Foxo1 signaling. Moreover, resveratrol treatment of hyperglycemic IRS2−/− mice decreased hepatic PTP1B mRNA and inhibited PTP1B activity, thereby restoring IRS1-mediated PI 3-kinase/Akt/Foxo1 signaling and peripheral insulin sensitivity. CONCLUSIONS By regulating the phosphorylation state of IR, PTB1B determines sensitivity to insulin in liver and exerts a unique role in the interplay between IRS1 and IRS2 in the modulation of hepatic insulin action. PMID:20028942

  7. Mixed-Alkali Effect in Li2O-Na2O-K2O-B2O3 Glasses: Infrared and Optical Absorption Studies

    Science.gov (United States)

    Samee, M. A.; Edukondalu, A.; Ahmmad, Shaik Kareem; Taqiullah, Sair Md.; Rahman, Syed

    2013-08-01

    The mixed-alkali effect (MAE) has been investigated in the glass system (40 - x)Li2O- xNa2O-10K2O-50B2O3 (0 mol% ≤ x ≤ 40 mol%) through density, modulated differential scanning calorimetry (DSC), and optical absorption studies. From the absorption studies, the values of the optical band gap ( E opt) for direct transition and Urbach energy (Δ E) have been evaluated. The values of E opt and Δ E show nonlinear behavior with the compositional parameter. The density and glass-transition temperature of the present glasses also show nonlinear variation, supporting the existence of MAE. The infrared (IR) spectra of the glasses reveal the presence of three- and four-coordinated boron atoms. The specific vibrations of Li-O, Na-O, and K-O bonds were observed in the present IR study.

  8. Two-Dimensional Infrared Study of Vibrational Coupling between Azide and Nitrile Reporters in a RNA Nucleoside.

    Science.gov (United States)

    Schmitz, Andrew J; Hogle, David G; Gai, Xin Sonia; Fenlon, Edward E; Brewer, Scott H; Tucker, Matthew J

    2016-09-08

    The vibrations in the azide, N3, asymmetric stretching region and nitrile, CN, symmetric stretching region of 2'-azido-5-cyano-2'-deoxyuridine (N3CNdU) are examined by two-dimensional infrared (2D IR) spectroscopy. At earlier waiting times, the 2D IR spectrum shows the presence of both vibrational transitions along the diagonal and off-diagonal cross peaks indicating vibrational coupling. The coupling strength is determined from the off-diagonal anharmonicity to be 66 cm(-1) for the intramolecular distance of ∼7.9 Å, based on a structural map generated for this model system. In addition, the frequency-frequency correlation decay is detected, monitoring the solvent dynamics around each individual probe position. Overall, these vibrational reporters can be utilized in tandem to simultaneously track global structural information and fast structural fluctuations.

  9. Structural, mechanical, and electronic properties of TaB2, TaB, IrB2, and IrB: First-principle calculations

    International Nuclear Information System (INIS)

    Zhao Wenjie; Wang Yuanxu

    2009-01-01

    First-principle calculations were performed to investigate the structural, elastic, and electronic properties of TaB 2 , TaB, IrB 2 , and IrB. The calculated equilibrium structural parameters, shear modulus, and Young's modulus of TaB 2 are well consistent with the available experimental data, and TaB 2 with P6/mmm space group has stronger directional bonding between ions than WB 2 , OsB 2 , IrN 2 , and PtN 2 . For TaB 2 , the hexagonal P6/mmm structure is more stable than the orthorhombic Pmmn one, while for IrB 2 the orthorhombic Pmmn structure is the most stable one. The high shear modulus of P6/mmm phase TaB 2 is mainly due to the strong covalent π-bonding of B-hexagon in the (0001) plane. Such a B-hexagon network can strongly resist against an applied [112-bar0] (0001) shear deformation. Correlation between the hardness and the elastic constants of TaB 2 was discussed. The band structure shows that P6/mmm phase TaB 2 and Pmmn phase IrB 2 are both metallic. The calculations show that both TaB and IrB are elastically stable with the hexagonal P6 3 /mmc structure. - Elastic constant c 44 of TaB 2 is calculated to be 235 GPa. This value is exceptionally high, exceeding those of WB 2 , OsB 2 , WB 4 , OsN 2 , IrN 2 , and PtN 2 .

  10. 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.

  11. Real time observation of proteolysis with Fourier transform infrared (FT-IR) and UV-circular dichroism spectroscopy: Watching a protease eat a protein

    Science.gov (United States)

    Güler, Günnur; Džafić, Enela; Vorob'ev, Mikhail M.; Vogel, Vitali; Mäntele, Werner

    2011-06-01

    Fourier transform infrared (FT-IR)- and UV-circular dichroism (UV-CD) spectroscopy have been used to study real-time proteolytic digestion of β-lactoglobulin (β-LG) and β-casein (β-CN) by trypsin at various substrate/enzyme ratios in D 2O-buffer at 37 °C. Both techniques confirm that protein substrate looses its secondary structure upon conversion to the peptide fragments. This perturbation alters the backbone of the protein chain resulting in conformational changes and degrading of the intact protein. Precisely, the most significant spectral changes which arise from digestion take place in the amide I and amide II regions. The FT-IR spectra for the degraded β-LG show a decrease around 1634 cm -1, suggesting a decrease of β-sheet structure in the course of hydrolysis. Similarly, the intensity around the 1654 cm -1 band decreases for β-CN digested by trypsin, indicating a reduction in the α-helical part. On the other hand, the intensity around ˜1594 cm -1 and ˜1406 cm -1 increases upon enzymatic breakdown of both substrates, suggesting an increase in the antisymmetric and symmetric stretching modes of free carboxylates, respectively, as released digestion products. Observation of further H/D exchange in the course of digestion manifests the structural opening of the buried groups and accessibility to the core of the substrate. On the basis of the UV-CD spectra recorded for β-LG and β-CN digested by trypsin, the unordered structure increases concomitant with a decrease in the remaining structure, thus, revealing breakdown of the intact protein into smaller fragments. This model study in a closed reaction system may serve as a basis for the much more complex digestion processes in an open reaction system such as the stomach.

  12. Infrared image processing devoted to thermal non-contact characterization-Applications to Non-Destructive Evaluation, Microfluidics and 2D source term distribution for multispectral tomography

    International Nuclear Information System (INIS)

    Batsale, Jean-Christophe; Pradere, Christophe

    2015-01-01

    The cost of IR cameras is more and more decreasing. Beyond the preliminary calibration step and the global instrumentation, the infrared image processing is then one of the key step for achieving in very broad domains.Generally the IR images are coming from the transient temperature field related to the emission of a black surface in response to an external or internal heating (active IR thermography). The first applications were devoted to the so called thermal Non-Destructive Evaluation methods by considering a thin sample and 1D transient heat diffusion through the sample (transverse diffusion). With simplified assumptions related to the transverse diffusion, the in-plane diffusion and transport phenomena can be also considered.A general equation can be applied in order to balance the heat transfer at the pixel scale or between groups of pixels in order to estimate several fields of thermophysical properties (heterogeneous field of in-plane diffusivity, flow distributions, source terms).There is a lot of possible strategies to process the space and time distributed big amount of data (previous integral transformation of the images, compression, elimination of the non useful areas...), generally based on the necessity to analyse the derivative versus space and time of the temperature field. Several illustrative examples related to the Non-Destructive Evaluation of heterogeneous solids, the thermal characterization of chemical reactions in microfluidic channels and the design of systems for multispectral tomography, will be presented. (paper)

  13. The effects of a 2 week modified high intensity interval training program on the homeostatic model of insulin resistance (HOMA-IR) in adults with type 2 diabetes.

    Science.gov (United States)

    Shaban, N; Kenno, K A; Milne, K J

    2014-04-01

    High intensity interval training (HIIT) induces similar metabolic adaptations to traditional steady state aerobic exercise training. Until recently, most HIIT studies have examined maximum efforts in healthy populations. The current study aimed to examine the effects of a 2 week modified HIIT program on the homeostatic model of insulin resistance (HOMA-IR) in individuals with type 2 diabetes (T2D). It was hypothesized that HIIT would improve HOMA-IR. Nine individuals with T2D (age=40.2±9.7 y; BMI=33.9±5.3; fasting plasma glucose [FPG]=8.7±2.9 mmol/L; HbA1C=7.3±1.2%; [mean±SD]) performed 6 individualized training sessions of HIIT (4x30 seconds at 100% of estimated maximum workload followed by 4 minutes of active rest) over 2 weeks. HOMA-IR was calculated from FPG and serum insulin and compared against a prior 2 week baseline period. Blood glucose was reduced immediately after each HIIT session (PHOMA-IR were unchanged after training. However, 6 of the 9 individuals exhibited reduced HOMA-IR values after the training period and there was a significant negative correlation between HOMA-IR value prior to training and change in HOMA-IR after HIIT. These observations tend to support the positive health benefits of HITT for individuals with T2D reported in recently published data using a modified HIIT protocol. However, they suggest that the magnitude of the disease should be assessed when examining the effects of exercise interventions in individuals with T2D.

  14. METS-IR, a novel score to evaluate insulin sensitivity, is predictive of visceral adiposity and incident type 2 diabetes.

    Science.gov (United States)

    Bello-Chavolla, Omar Yaxmehen; Almeda-Valdes, Paloma; Gomez-Velasco, Donaji; Viveros-Ruiz, Tannia; Cruz-Bautista, Ivette; Romo-Romo, Alonso; Sánchez-Lázaro, Daniel; Meza-Oviedo, Dushan; Vargas-Vázquez, Arsenio; Campos, Olimpia Arellano; Sevilla-González, Magdalena Del Rocío; Martagón, Alexandro J; Hernández, Liliana Muñoz; Mehta, Roopa; Caballeros-Barragán, César Rodolfo; Aguilar-Salinas, Carlos A

    2018-05-01

    We developed a novel non-insulin-based fasting score to evaluate insulin sensitivity validated against the euglycemic-hyperinsulinemic clamp (EHC). We also evaluated its correlation with ectopic fact accumulation and its capacity to predict incident type 2 diabetes mellitus (T2D). The discovery sample was composed by 125 subjects (57 without and 68 with T2D) that underwent an EHC. We defined METS-IR as Ln((2*G 0 )+TG 0 )*BMI)/(Ln(HDL-c)) (G 0 : fasting glucose, TG 0 : fasting triglycerides, BMI: body mass index, HDL-c: high-density lipoprotein cholesterol), and compared its diagnostic performance against the M-value adjusted by fat-free mass (MFFM) obtained by an EHC. METS-IR was validated in a sample with EHC data, a sample with modified frequently sampled intravenous glucose tolerance test (FSIVGTT) data and a large cohort against HOMA-IR. We evaluated the correlation of the score with intrahepatic and intrapancreatic fat measured using magnetic resonance spectroscopy. Subsequently, we evaluated its ability to predict incident T2D cases in a prospective validation cohort of 6144 subjects. METS-IR demonstrated the better correlation with the MFFM ( ρ  = -0.622, P  index obtained from the FSIVGTT (AUC: 0.67, 95% CI: 0.53-0.81). METS-IR significantly correlated with intravisceral, intrahepatic and intrapancreatic fat and fasting insulin levels ( P  50.39) had the highest adjusted risk to develop T2D (HR: 3.91, 95% CI: 2.25-6.81). Furthermore, subjects with incident T2D had higher baseline METS-IR compared to healthy controls (50.2 ± 10.2 vs 44.7 ± 9.2, P  < 0.001). METS-IR is a novel score to evaluate cardiometabolic risk in healthy and at-risk subjects and a promising tool for screening of insulin sensitivity. © 2018 European Society of Endocrinology.

  15. SH2-B promotes insulin receptor substrate 1 (IRS1)- and IRS2-mediated activation of the phosphatidylinositol 3-kinase pathway in response to leptin.

    Science.gov (United States)

    Duan, Chaojun; Li, Minghua; Rui, Liangyou

    2004-10-15

    Leptin regulates energy homeostasis primarily by binding and activating its long form receptor (LRb). Deficiency of either leptin or LRb causes morbid obesity. Leptin stimulates LRb-associated JAK2, thus initiating multiple pathways including the Stat3 and phosphatidylinositol (PI) 3-kinase pathways that mediate leptin biological actions. Here we report that SH2-B, a JAK2-interacting protein, promotes activation of the PI 3-kinase pathway by recruiting insulin receptor substrate 1 (IRS1) and IRS2 in response to leptin. SH2-B directly bound, via its PH and SH2 domain, to both IRS1 and IRS2 both in vitro and in intact cells and mediated formation of a JAK2/SH2-B/IRS1 or IRS2 tertiary complex. Consequently, SH2-B dramatically enhanced leptin-stimulated tyrosine phosphorylation of IRS1 and IRS2 in HEK293 cells stably expressing LRb, thus promoting association of IRS1 and IRS2 with the p85 regulatory subunit of PI 3-kinase and phosphorylation and activation of Akt. SH2-B mutants with lower affinity for IRS1 and IRS2 exhibited reduced ability to promote association of JAK2 with IRS1, tyrosine phosphorylation of IRS1, and association of IRS1 with p85 in response to leptin. Moreover, deletion of the SH2-B gene impaired leptin-stimulated tyrosine phosphorylation of endogenous IRS1 in mouse embryonic fibroblasts (MEF), which was reversed by reintroduction of SH2-B. Similarly, SH2-B promoted growth hormone-stimulated tyrosine phosphorylation of IRS1 in both HEK293 and MEF cells. Our data suggest that SH2-B is a novel mediator of the PI 3-kinase pathway in response to leptin or other hormones and cytokines that activate JAK2.

  16. History of infrared detectors

    Science.gov (United States)

    Rogalski, A.

    2012-09-01

    This paper overviews the history of infrared detector materials starting with Herschel's experiment with thermometer on February 11th, 1800. Infrared detectors are in general used to detect, image, and measure patterns of the thermal heat radiation which all objects emit. At the beginning, their development was connected with thermal detectors, such as thermocouples and bolometers, which are still used today and which are generally sensitive to all infrared wavelengths and operate at room temperature. The second kind of detectors, called the photon detectors, was mainly developed during the 20th Century to improve sensitivity and response time. These detectors have been extensively developed since the 1940's. Lead sulphide (PbS) was the first practical IR detector with sensitivity to infrared wavelengths up to ˜3 μm. After World War II infrared detector technology development was and continues to be primarily driven by military applications. Discovery of variable band gap HgCdTe ternary alloy by Lawson and co-workers in 1959 opened a new area in IR detector technology and has provided an unprecedented degree of freedom in infrared detector design. Many of these advances were transferred to IR astronomy from Departments of Defence research. Later on civilian applications of infrared technology are frequently called "dual-use technology applications." One should point out the growing utilisation of IR technologies in the civilian sphere based on the use of new materials and technologies, as well as the noticeable price decrease in these high cost technologies. In the last four decades different types of detectors are combined with electronic readouts to make detector focal plane arrays (FPAs). Development in FPA technology has revolutionized infrared imaging. Progress in integrated circuit design and fabrication techniques has resulted in continued rapid growth in the size and performance of these solid state arrays.

  17. THE INFRARED SPECTRUM OF PROTONATED OVALENE IN SOLID PARA-HYDROGEN AND ITS POSSIBLE CONTRIBUTION TO INTERSTELLAR UNIDENTIFIED INFRARED EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Tsuge, Masashi; Bahou, Mohammed; Lee, Yuan-Pern [Department of Applied Chemistry and Institute of Molecular Sciences, National Chiao Tung University, 1001, Ta-Hsueh Road, Hsinchu 30010, Taiwan (China); Wu, Yu-Jong [National Synchrotron Radiation Research Center, 101, Hsin-Ann Road, Hsinchu 30076, Taiwan (China); Allamandola, Louis, E-mail: tsuge@nctu.edu.tw, E-mail: yplee@mail.nctu.edu.tw [The Astrophysics and Astrochemistry Laboratory, NASA Ames Research Center, Moffett Field, CA 94035 (United States)

    2016-07-10

    The mid-infrared emission from galactic objects, including reflection nebulae, planetary nebulae, proto-planetary nebulae, molecular clouds, etc, as well as external galaxies, is dominated by the unidentified infrared (UIR) emission bands. Large protonated polycyclic aromatic hydrocarbons (H{sup +}PAHs) were proposed as possible carriers, but no spectrum of an H{sup +}PAH has been shown to exactly match the UIR bands. Here, we report the IR spectrum of protonated ovalene (7-C{sub 32}H{sub 15} {sup +}) measured in a para -hydrogen ( p -H{sub 2}) matrix at 3.2 K, generated by bombarding a mixture of ovalene and p -H{sub 2} with electrons during matrix deposition. Spectral assignments were made based on the expected chemistry and on the spectra simulated with the wavenumbers and infrared intensities predicted with the B3PW91/6-311++G(2d,2p) method. The close resemblance of the observed spectral pattern to that of the UIR bands suggests that protonated ovalene may contribute to the UIR emission, particularly from objects that emit Class A spectra, such as the IRIS reflection nebula, NGC 7023.

  18. Structure, magnetism, and transport properties for Ca doping in Sr2IrO4

    Directory of Open Access Journals (Sweden)

    Guotai Zhou

    2017-05-01

    Full Text Available An immediate quenching using liquid N2 is applied for synthesizing the 5d transition-metal oxides (Sr1-xCax2IrO4 (0 ≤ x ≤ 0.15 single phase. X-ray diffraction together with Rietveld refinement shows that the lattice parameters along a and c directions and the bond angle of Ir-O2-Ir decrease with the increase of Ca content. X-ray Absorption Fine Spectroscopy measurements prove that the valence of Ir and the average Ir-O bond-length substantially remain unchanged with Ca content increasing in the phase. The effective magnetic moment μeff and Néel temperature TN decrease simultaneously with increased Ca content. Electrical resistivity shows complex temperature dependence behavior, which follows the three-dimensional variable range hopping behavior at low temperature, Arrhenius-type behavior at middle-temperature, and a weak electronic localization in quasi-two-dimensional at high temperature.

  19. Development of paints with infrared radiation reflective properties

    Directory of Open Access Journals (Sweden)

    Eliane Coser

    2015-06-01

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

  20. DIRECT-DEPOSITION INFRARED SPECTROMETRY WITH GAS AND SUPERCRITICAL FLUID CHROMATOGRAPHY

    Science.gov (United States)

    A direct-deposition Fourier transform infrared (FT-IR) system has been evaluated for applicability to gas chromatography (GC) and supercritical fluid chromatography (SFC) of environmental analytes. A 100-um i.d. fused-silica transfer line was used for GC, and a 50-um transfer lin...

  1. Design of a compact athermalized infrared seeker

    Science.gov (United States)

    Gao, Qing-jia; Wang, Jian; Sun, Qiang

    2017-07-01

    In order to meet the application requirement of a certain long wavelength infrared (LWIR) seeker, a small volume, light weight and passively athermalized infrared (IR) objective is designed in this paper. The two-lens telephoto structure is adopted by merely using aluminum alloy as the housing material. By balancing the thermo-optical coefficient and thermal expansion coefficient of materials, an athermalized IR seeker with effective focal length of 90 mm and F number of 1.2 is achieved. The whole optical length is 75 mm, and the weight is only 234 g. The objective can remain fine imaging quality under temperature range from -40 °C to 60 °C, which is beneficial to the lightweight design of IR seekers.

  2. Vasorelaxation Study and Tri-Step Infrared Spectroscopy Analysis of Malaysian Local Herbs

    Directory of Open Access Journals (Sweden)

    Yung Sing Ch’ng

    2016-06-01

    Full Text Available Objectives: The aim of this paper is to investigate the activities of Malaysian local herbs (Clinacanthus nutans Lindau, Strobilanthes crispus, Murdannia bracteata, Elephantopus scaber Linn., Pereskia bleo, Pereskia grandifolia Haw., Vernonia amygdalina, and Swietenia macrophylla King for anti-hypertensive and vasorelaxant activity. An infrared (IR macro-fingerprinting technique consisting of conventional fourier transform IR (FTIR, second-derivative IR (SD-IR, and two-dimensional correlation IR (2D-correlation IR analyses were used to determine the main constituents and the fingerprints of the Malaysian local herbs. Methods: The herbs were collected, ground into powder form, and then macerated by using three different solvents: distilled water, 50% ethanol, and 95% ethanol, respectively. The potentials of the extracts produced from these herbs for use as vasorelaxants were determined. Additionally, the fingerprints of these herbs were analyzed by using FTIR spectra, SD-IR spectra, and 2D-correlation IR spectra in order to identify their main constituents and to provide useful information for future pharmacodynamics studies. Results: Swietenia macrophylla King has the highest potential in terms of vasorelaxant activity, followed by Vernonia amygdalina, Pereskia bleo, Strobilanthes crispus, Elephantopus scaber Linn., Pereskia grandifolia Haw., Clinacanthus nutans Lindau, and Murdannia bracteata. The tri-step IR macro-fingerprint of the herbs revealed that most of them contained proteins. Pereskia bleo and Pereskia grandifolia Haw. were found to contain calcium oxalate while Swietenia macrophylla King was found to contain large amounts of flavonoids. Conclusion: The flavonoid content of the herbs affects their vasorelaxant activity, and the tri-step IR macro- fingerprint method can be used as an analytical tool to determine the activity of a herbal medicine in terms of its vasorelaxant effect.

  3. Genetic variant near IRS1 is associated with type 2 diabetes, insulin resistance and hyperinsulinemia

    DEFF Research Database (Denmark)

    Rung, Johan; Cauchi, Stéphane; Albrechtsen, Anders

    2009-01-01

    sample of 4,977 French individuals. We then selected the 28 best hits for replication in 7,698 Danish subjects and identified 4 SNPs showing strong association with T2D, one of which (rs2943641, P = 9.3 x 10(-12), OR = 1.19) was located adjacent to the insulin receptor substrate 1 gene (IRS1). Unlike...... previously reported T2D risk loci, which predominantly associate with impaired beta cell function, the C allele of rs2943641 was associated with insulin resistance and hyperinsulinemia in 14,358 French, Danish and Finnish participants from population-based cohorts; this allele was also associated...... with reduced basal levels of IRS1 protein and decreased insulin induction of IRS1-associated phosphatidylinositol-3-OH kinase activity in human skeletal muscle biopsies....

  4. A survey of infrared continuum versus line radiation from metal halide lamps

    International Nuclear Information System (INIS)

    Kato, M; Herd, M T; Lawler, J E

    2008-01-01

    Near-infrared radiation (near-IR) losses from the arcs of six commercial metal halide high intensity discharge (MH-HID) lamps with various power levels and with both Na/Sc and rare earth doses were surveyed in this paper. A radiometrically calibrated Fourier transform infrared spectrometer was used. Lamps with rare earth doses have appreciably better color rendering indices (CRIs) than lamps with Na/Sc doses. The ratios of near-IR continuum emission over near-IR line emission from these six lamps were compared. The near-IR continuum dominates near-IR losses from lamps with rare earth doses and the continuum is significant, but not dominant, from lamps with Na/Sc doses. There was no strong dependence of this ratio on input power or color temperature (T c ). Total near-IR losses were estimated using absolutely calibrated, horizontal irradiance measurements. Estimated total near-IR losses were correlated with CRI. The lamps with rare earth doses yield the best CRIs, but have appreciably higher near-IR losses due primarily to continuum processes. One of these rare earth MH-HID lamps was used in a more detailed study of the microscopic physics of the continuum mechanism (Herd M T and Lawler E 2007 J. Phys. D: Appl. Phys. 40 3386)

  5. Bond deformation paths and electronic instabilities of ultraincompressible transition metal diborides: Case study of OsB2 and IrB2

    Science.gov (United States)

    Zhang, R. F.; Legut, D.; Wen, X. D.; Veprek, S.; Rajan, K.; Lookman, T.; Mao, H. K.; Zhao, Y. S.

    2014-09-01

    The energetically most stable orthorhombic structure of OsB2 and IrB2 is dynamically stable for OsB2 but unstable for IrB2. Both diborides have substantially lower shear strength in their easy slip systems than their metal counterparts. This is attributed to an easy sliding facilitated by out-of-plane weakening of metallic Os-Os bonds in OsB2 and by an in-plane bond splitting instability in IrB2. A much higher shear resistance of Os-B and B-B bonds than Os-Os ones is found, suggesting that the strengthened Os-B and B-B bonds are responsible for hardness enhancement in OsB2. In contrast, an in-plane electronic instability in IrB2 limits its strength. The electronic structure of deformed diborides suggests that the electronic instabilities of 5d orbitals are their origin of different bond deformation paths. Neither IrB2 nor OsB2 can be intrinsically superhard.

  6. Fluorenyl benzothiadiazole and benzoselenadiazole near-IR fluorescent probes for two-photon fluorescence imaging (Conference Presentation)

    Science.gov (United States)

    Belfield, Kevin D.; Yao, Sheng; Kim, Bosung; Yue, Xiling

    2016-03-01

    Imaging biological samples with two-photon fluorescence (2PF) microscopy has the unique advantage of resulting high contrast 3D resolution subcellular image that can reach up to several millimeters depth. 2PF probes that absorb and emit at near IR region need to be developed. Two-photon excitation (2PE) wavelengths are less concerned as 2PE uses wavelengths doubles the absorption wavelength of the probe, which means 2PE wavelengths for probes even with absorption at visible wavelength will fall into NIR region. Therefore, probes that fluoresce at near IR region with high quantum yields are needed. A series of dyes based on 5-thienyl-2, 1, 3-benzothiadiazole and 5-thienyl-2, 1, 3-benzoselenadiazole core were synthesized as near infrared two-photon fluorophores. Fluorescence maxima wavelengths as long as 714 nm and fluorescence quantum yields as high as 0.67 were achieved. The fluorescence quantum yields of the dyes were nearly constant, regardless of solvents polarity. These diazoles exhibited large Stokes shift (GM), and high two-photon fluorescence figure of merit (FM , 1.04×10-2 GM). Cells incubated on a 3D scaffold with one of the new probes (encapsulated in Pluronic micelles) exhibited bright fluorescence, enabling 3D two-photon fluorescence imaging to a depth of 100 µm.

  7. Feasibility Study on the Development of 2-channel Embedded Infrared Fiber-optic Sensor for Thermometry of Secondary Water System in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Yoo, W. J.; Jang, K. W.; Seo, J. K.; Moon, J.; Han, K. T.; Lee, B.; Park, B. G.

    2011-01-01

    Any warm object by measuring the emitted infrared (IR) radiation. The radiometers using infrared optical fibers are based on the relationship between the temperature of a heat source and the quality and the quantity of an IR radiation. To measure physical properties including a temperature, optical fiber-based sensor has many advantages, such as small size, low cost, high resolution, remote sensing and immunity to electromagnetic radiation over conventional electrical sensors. In this study, we carried out the feasibility study on the development of an embedded IR fiber-optic sensor for thermometry of the secondary water system in a nuclear power plant. The 2-channel embedded fiberoptic temperature sensor was fabricated using two identical IR optical fibers for accurate thermometry without complicated calibration processes. To decide accurate temperature of the water, we measured the difference between the IR radiations emitted from the two temperature sensing probes according to the temperature variation of the water

  8. Preparation, characterization and infrared emissivity study of helical polyurethane-SiO2 core-shell composite

    International Nuclear Information System (INIS)

    Wang Zhiqiang; Zhou Yuming; Yao Qingzhao; Sun Yanqing

    2009-01-01

    Helical polyurethane-SiO 2 (HPU-SiO 2 ) core-shell composite was prepared after surface modification of SiO 2 nanoparticles. HPU-SiO 2 was characterized by Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), ultraviolet (UV) spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicate that the helical polyurethane has been successfully grafted onto the surfaces of the modified SiO 2 . HPU-SiO 2 composite exhibits clearly core-shell structure. The ultraviolet absorption and crystallizability of HPU-SiO 2 are changed due to the shell of helical polyurethane, which possesses regular single-handed conformation and inter-chain hydrogen bonds. The infrared emissivity of HPU-SiO 2 was also investigated. The result indicates that the interfacial interactions between organic shell and inorganic core induce the infrared emissivity value being reduced from 0.781 for SiO 2 to 0.503 for HPU-SiO 2 .

  9. RADIO MONITORING OF THE PERIODICALLY VARIABLE IR SOURCE LRLL 54361: NO DIRECT CORRELATION BETWEEN THE RADIO AND IR EMISSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Forbrich, Jan, E-mail: jan.forbrich@univie.ac.at [University of Vienna, Department of Astrophysics, Türkenschanzstraße 17, A-1180 Vienna (Austria); Rodríguez, Luis F.; Palau, Aina; Zapata, Luis A. [Instituto de Radioastronomía y Astrofísica, UNAM, Apdo. Postal 3-72 (Xangari), 58089 Morelia, Michoacán (Mexico); Muzerolle, James [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Gutermuth, Robert A. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)

    2015-11-20

    LRLL 54361 is an infrared source located in the star-forming region IC 348 SW. Remarkably, its infrared luminosity increases by a factor of 10 over roughly one week every 25.34 days. To understand the origin of these remarkable periodic variations, we obtained sensitive 3.3 cm JVLA radio continuum observations of LRLL 54361 and its surroundings in six different epochs: three of them during the IR-on state and three during the IR-off state. The radio source associated with LRLL 54361 remained steady and did not show a correlation with the IR variations. We suggest that the IR is tracing the results of fast (with a timescale of days) pulsed accretion from an unseen binary companion, while the radio traces an ionized outflow with an extent of ∼100 AU that smooths out the variability over a period of the order of a year. The average flux density measured in these 2014 observations, 27 ± 5 μJy, is about a factor of two less than that measured about 1.5 years before, 53 ± 11 μJy, suggesting that variability in the radio is present, but over larger timescales than in the IR. We discuss other sources in the field, in particular two infrared/X-ray stars that show rapidly varying gyrosynchrotron emission.

  10. High-resolution T1-weighted 3D real IR imaging of the temporal bone using triple-dose contrast material

    Energy Technology Data Exchange (ETDEWEB)

    Naganawa, Shinji; Koshikawa, Tokiko; Nakamura, Tatsuya; Fukatsu, Hiroshi; Ishigaki, Takeo [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, Shouwa-ku, 466-8550, Nagoya (Japan); Aoki, Ikuo [Medical System Company, Toshiba Corporation, Tokyo (Japan)

    2003-12-01

    The small structures in the temporal bone are surrounded by bone and air. The objectives of this study were (a) to compare contrast-enhanced T1-weighted images acquired by fast spin-echo-based three-dimensional real inversion recovery (3D rIR) against those acquired by gradient echo-based 3D SPGR in the visualization of the enhancement of small structures in the temporal bone, and (b) to determine whether either 3D rIR or 3D SPGR is useful for visualizing enhancement of the cochlear lymph fluid. Seven healthy men (age range 27-46 years) volunteered to participate in this study. All MR imaging was performed using a dedicated bilateral quadrature surface phased-array coil for temporal bone imaging at 1.5 T (Visart EX, Toshiba, Tokyo, Japan). The 3D rIR images (TR/TE/TI: 1800 ms/10 ms/500 ms) and flow-compensated 3D SPGR images (TR/TE/FA: 23 ms/10 ms/25 ) were obtained with a reconstructed voxel size of 0.6 x 0.7 x 0.8 mm{sup 3}. Images were acquired before and 1, 90, 180, and 270 min after the administration of triple-dose Gd-DTPA-BMA (0.3 mmol/kg). In post-contrast MR images, the degree of enhancement of the cochlear aqueduct, endolymphatic sac, subarcuate artery, geniculate ganglion of the facial nerve, and cochlear lymph fluid space was assessed by two radiologists. The degree of enhancement was scored as follows: 0 (no enhancement); 1 (slight enhancement); 2 (intermediate between 1 and 3); and 3 (enhancement similar to that of vessels). Enhancement scores for the endolymphatic sac, subarcuate artery, and geniculate ganglion were higher in 3D rIR than in 3D SPGR. Washout of enhancement in the endolymphatic sac appeared to be delayed compared with that in the subarcuate artery, suggesting that the enhancement in the endolymphatic sac may have been due in part to non-vascular tissue enhancement. Enhancement of the cochlear lymph space was not observed in any of the subjects in 3D rIR and 3D SPGR. The 3D rIR sequence may be more sensitive than the 3D SPGR sequence in

  11. Role of IRS-2 in insulin and cytokine signalling.

    Science.gov (United States)

    Sun, X J; Wang, L M; Zhang, Y; Yenush, L; Myers, M G; Glasheen, E; Lane, W S; Pierce, J H; White, M F

    1995-09-14

    The protein IRS-1 acts as an interface between signalling proteins with Src-homology-2 domains (SH2 proteins) and the receptors for insulin, IGF-1, growth hormone, several interleukins (IL-4, IL-9, IL-13) and other cytokines. It regulates gene expression and stimulates mitogenesis, and appears to mediate insulin/IGF-1-stimulated glucose transport. Thus, survival of the IRS-1-/- mouse with only mild resistance to insulin was surprising. This dilemma is provisionally resolved with our discovery of a second IRS-signalling protein. We purified and cloned a likely candidate called 4PS from myeloid progenitor cells and, because of its resemblance to IRS-1, we designate it IRS-2. Alignment of the sequences of IRS-2 and IRS-1 revealed a highly conserved amino terminus containing a pleckstrin-homology domain and a phosphotyrosine-binding domain, and a poorly conserved carboxy terminus containing several tyrosine phosphorylation motifs. IRS-2 is expressed in many cells, including tissues from IRS-1-/- mice, and may be essential for signalling by several receptor systems.

  12. Characterization of proton in Y-doped SrZrO3 polycrystal by IR spectroscopy

    International Nuclear Information System (INIS)

    Hibino, T.; Mizutani, K.; Yajima, T.; Iwahara, H.

    1992-01-01

    To characterize proton in Y-doped SrZrO 3 polycrystal, protonic conductivities and infrared spectra were measured. IR spectra exhibited 2 OH bands in 3500-2800 and 2650-2300 cm -1 regions, indicating that proton was bound to lattice oxide ion and that its strength of bonding was rather weak. The decrease in conductivity by replacing H + with D + suggested that the conducting ion was not hydroxide but proton and that it migrated via the dissociation of O-H bond. (author). 15 refs., 5 figs

  13. Sex-specific interactions between the IRS1 polymorphism and intakes of carbohydrates and fat on incident type 2 diabetes.

    Science.gov (United States)

    Ericson, Ulrika; Rukh, Gull; Stojkovic, Ivana; Sonestedt, Emily; Gullberg, Bo; Wirfält, Elisabet; Wallström, Peter; Orho-Melander, Marju

    2013-01-01

    The minor T allele of rs2943641 near the gene encoding for insulin receptor substrate 1 (IRS1) has been associated with decreased risk of type 2 diabetes (T2D) and adiposity in genome-wide association studies. Dietary intake can influence the regulation of IRS1, and studies have indicated sex-specific associations between IRS1 and adiposity. The objective was to examine the interaction between IRS1 rs2943641 and macronutrient intakes on incident T2D and percentage body fat in the Malmö Diet and Cancer cohort. The study included 15,227 women and 9614 men aged 45-74 y without prevalent diabetes. Dietary data were collected with a modified diet history method. During 12 y of follow-up, 1567 incident T2D cases were identified. The T allele was associated with lower incidence of T2D (P-trend = 0.003) and, in men, with higher percentage body fat (P-trend = 0.00002). We observed 3-way interactions between sex, rs2943641, and carbohydrate intake (P = 0.01) as well as between sex, rs2943641, and fat intake (P = 0.01) on incident T2D. Among women, the T allele was associated with decreased risk only in the lower tertiles of carbohydrate intake (P-trend = 0.01, P-interaction = 0.01). In contrast, among men, the T allele was associated with decreased risk in the lowest tertile of fat intake (P-trend = 0.01, P-interaction = 0.02). No interaction was observed between macronutrient intakes and rs2943641 on percentage body fat. Our results indicate that IRS1 rs2943641 interacts with carbohydrate and fat intakes on incident T2D in a sex-specific fashion. A protective association between the rs2943641 T allele and T2D was restricted to women with low carbohydrate intake and to men with low fat intake.

  14. Evidence for anionic redox activity in a tridimensional-ordered Li-rich positive electrode β-Li2IrO3.

    Science.gov (United States)

    Pearce, Paul E; Perez, Arnaud J; Rousse, Gwenaelle; Saubanère, Mathieu; Batuk, Dmitry; Foix, Dominique; McCalla, Eric; Abakumov, Artem M; Van Tendeloo, Gustaaf; Doublet, Marie-Liesse; Tarascon, Jean-Marie

    2017-05-01

    Lithium-ion battery cathode materials have relied on cationic redox reactions until the recent discovery of anionic redox activity in Li-rich layered compounds which enables capacities as high as 300 mAh g -1 . In the quest for new high-capacity electrodes with anionic redox, a still unanswered question was remaining regarding the importance of the structural dimensionality. The present manuscript provides an answer. We herein report on a β-Li 2 IrO 3 phase which, in spite of having the Ir arranged in a tridimensional (3D) framework instead of the typical two-dimensional (2D) layers seen in other Li-rich oxides, can reversibly exchange 2.5 e - per Ir, the highest value ever reported for any insertion reaction involving d-metals. We show that such a large activity results from joint reversible cationic (M n+ ) and anionic (O 2 ) n- redox processes, the latter being visualized via complementary transmission electron microscopy and neutron diffraction experiments, and confirmed by density functional theory calculations. Moreover, β-Li 2 IrO 3 presents a good cycling behaviour while showing neither cationic migration nor shearing of atomic layers as seen in 2D-layered Li-rich materials. Remarkably, the anionic redox process occurs jointly with the oxidation of Ir 4+ at potentials as low as 3.4 V versus Li + /Li 0 , as equivalently observed in the layered α-Li 2 IrO 3 polymorph. Theoretical calculations elucidate the electrochemical similarities and differences of the 3D versus 2D polymorphs in terms of structural, electronic and mechanical descriptors. Our findings free the structural dimensionality constraint and broaden the possibilities in designing high-energy-density electrodes for the next generation of Li-ion batteries.

  15. Search for bright stars with infrared excess

    Energy Technology Data Exchange (ETDEWEB)

    Raharto, Moedji, E-mail: moedji@as.itb.ac.id [Astronomy Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2014-03-24

    Bright stars, stars with visual magnitude smaller than 6.5, can be studied using small telescope. In general, if stars are assumed as black body radiator, then the color in infrared (IR) region is usually equal to zero. Infrared data from IRAS observations at 12 and 25μm (micron) with good flux quality are used to search for bright stars (from Bright Stars Catalogues) with infrared excess. In magnitude scale, stars with IR excess is defined as stars with IR color m{sub 12}−m{sub 25}>0; where m{sub 12}−m{sub 25} = −2.5log(F{sub 12}/F{sub 25})+1.56, where F{sub 12} and F{sub 25} are flux density in Jansky at 12 and 25μm, respectively. Stars with similar spectral type are expected to have similar color. The existence of infrared excess in the same spectral type indicates the existence of circum-stellar dust, the origin of which is probably due to the remnant of pre main-sequence evolution during star formation or post AGB evolution or due to physical process such as the rotation of those stars.

  16. IR characteristic simulation of city scenes based on radiosity model

    Science.gov (United States)

    Xiong, Xixian; Zhou, Fugen; Bai, Xiangzhi; Yu, Xiyu

    2013-09-01

    Reliable modeling for thermal infrared (IR) signatures of real-world city scenes is required for signature management of civil and military platforms. Traditional modeling methods generally assume that scene objects are individual entities during the physical processes occurring in infrared range. However, in reality, the physical scene involves convective and conductive interactions between objects as well as the radiations interactions between objects. A method based on radiosity model describes these complex effects. It has been developed to enable an accurate simulation for the radiance distribution of the city scenes. Firstly, the physical processes affecting the IR characteristic of city scenes were described. Secondly, heat balance equations were formed on the basis of combining the atmospheric conditions, shadow maps and the geometry of scene. Finally, finite difference method was used to calculate the kinetic temperature of object surface. A radiosity model was introduced to describe the scattering effect of radiation between surface elements in the scene. By the synthesis of objects radiance distribution in infrared range, we could obtain the IR characteristic of scene. Real infrared images and model predictions were shown and compared. The results demonstrate that this method can realistically simulate the IR characteristic of city scenes. It effectively displays the infrared shadow effects and the radiation interactions between objects in city scenes.

  17. Ion beam synthesis of IrSi3 by implantation of 2 MeV Ir ions

    International Nuclear Information System (INIS)

    Sjoreen, T.P.; Chisholm, M.F.; Hinneberg, H.J.

    1992-11-01

    Formation of a buried IrSi 3 layer in (111) oriented Si by ion implantation and annealing has been studied at an implantation energy of 2 MeV for substrate temperatures of 450--550C. Rutherford backscattering (RBS), ion channeling and cross-sectional transmission electron microscopy showed that a buried epitaxial IrSi 3 layer is produced at 550C by implanting ≥ 3.4 x 10 17 Ir/cm 2 and subsequently annealing for 1 h at 1000C plus 5 h at 1100C. At a dose of 3.4 x 10 17 Ir/cm 2 , the thickness of the layer varied between 120 and 190 nm and many large IrSi 3 precipitates were present above and below the film. Increasing the dose to 4.4 x 10 17 Ir/cm 2 improved the layer uniformity at the expense of increased lattice damage in the overlying Si. RBS analysis of layer formation as a function of substrate temperature revealed the competition between the mechanisms for optimizing surface crystallinity vs. IrSi 3 layer formation. Little apparent substrate temperature dependence was evident in the as-implanted state but after annealing the crystallinity of the top Si layer was observed to deteriorate with increasing substrate temperature while the precipitate coarsening and coalescence improved

  18. Single mode operation of a hybrid optically pumped D2O far infrared laser

    International Nuclear Information System (INIS)

    Yuan, D.C.; Siegrist, M.R.

    1990-04-01

    We have achieved single mode operation in a hybrid optically pumped D 2 O far infrared laser. The active volume of the resonator was divided into two sections separated by a thin plastic foil. The larger section served as the main gain medium and the shorter section as mode selective element. The vapor pressure in the smaller volume was either very low or alternatively about 3 times higher than the pressure in the main part. In both cases single mode operation was achieved without any reduction of the total output energy. (author) 13 refs., 7 figs

  19. Vibrationally enhanced associative photodesorption of H{sub 2} (D{sub 2}) from Ru(0001). Quantum and classical approaches

    Energy Technology Data Exchange (ETDEWEB)

    Vazhappilly, Tijo Joseph

    2008-04-15

    This thesis investigates the femtosecond laser induced associative photodesorption of hydrogen, H{sub 2}, and deuterium, D{sub 2}, from a ruthenium metal surface. One of the goals of the present thesis is to suggest, on the basis of theoretical simulations, strategies to control/enhance the photodesorption yield from Ru(0001). For this purpose, we suggest a hybrid scheme to control the reaction, where the adsorbate vibrations are initially excited by an infrared (IR) pulse, prior to the vis pulse. Both adiabatic and non-adiabatic representations for photoinduced desorption problems are employed here. The adiabatic representation is realized within the classical picture using Molecular Dynamics (MD) with electronic frictions. In a quantum mechanical description, non-adiabatic representations are employed within open-system density matrix theory. The time evolution of the desorption process is studied using a two-mode reduced dimensionality model with one vibrational coordinate and one translational coordinate of the adsorbate. The ground and excited electronic state potentials, and dipole function for the IR excitation are taken from first principles. The IR driven vibrational excitation of adsorbate modes with moderate efficiency is achieved by (modified) {pi}-pulses or/and optimal control theory. The fluence dependence of the desorption reaction is computed by including the electronic temperature of the metal calculated from the two-temperature model. We then employed the IR+vis strategy in both models. Here, we found that vibrational excitation indeed promotes the desorption of hydrogen and deuterium. (orig.)

  20. Radiometric characterization of type-II InAs/GaSb superlattice (t2sl) midwave infrared photodetectors and focal plane arrays

    Science.gov (United States)

    Nghiem, Jean; Giard, E.; Delmas, M.; Rodriguez, J. B.; Christol, P.; Caes, M.; Martijn, H.; Costard, E.; Ribet-Mohamed, I.

    2017-09-01

    In recent years, Type-II InAs/GaSb superlattice (T2SL) has emerged as a new material technology suitable for high performance infrared (IR) detectors operating from Near InfraRed (NIR, 2-3μm) to Very Long Wavelength InfraRed (LWIR, λ > 15μm) wavelength domains. To compare their performances with well-established IR technologies such as MCT, InSb or QWIP cooled detectors, specific electrical and radiometric characterizations are needed: dark current, spectral response, quantum efficiency, temporal and spatial noises, stability… In this paper, we first present quantum efficiency measurements performed on T2SL MWIR (3-5μm) photodiodes and on one focal plane array (320x256 pixels with 30μm pitch, realized in the scope of a french collaboration ). Different T2SL structures (InAs-rich versus GaSb-rich) with the same cutoff wavelength (λc= 5μm at 80K) were studied. Results are analysed in term of carrier diffusion length in order to define the optimum thickness and type of doping of the absorbing zone. We then focus on the stability over time of a commercial T2SL FPA (320x256 pixels with 30μm pitch), measuring the commonly used residual fixed pattern noise (RFPN) figure of merit. Results are excellent, with a very stable behaviour over more than 3 weeks, and less than 10 flickering pixels, possibly giving access to long-term stability of IR absolute calibration.

  1. Multi-center vs. two-center bonding within the hetero-polyanion in Eu{sub 2}GaPt{sub 2} and its prototype Ca{sub 2}SiIr{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Poettgen, Rainer [Institut fuer Anorganische und Analytische Chemie, Universitaet Muenster (Germany); Borrmann, Horst; Grin, Yuri [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Dresden (Germany)

    2017-11-17

    The compound Eu{sub 2}GaPt{sub 2} was synthesized from the elements in a sealed tantalum tube. Its Ca{sub 2}SiIr{sub 2}-type crystal structure was refined from single-crystal X-ray diffraction data: space group C2/c, a = 9.8775(6), b = 5.8621(6), c = 7.9677(5) Aa, β = 102.257(4) , R{sub F} = 0.039, 1344 observed reflections, and 25 variable parameters. The platinum (iridium) atoms in Eu{sub 2}GaPt{sub 2} and Ca{sub 2}SiIr{sub 2} form linear chains of dumbbells [2c(Pt-Pt) or 2c(Ir-Ir) bonds, respectively]. These chains are interconnected to 2D polyanions in Eu{sub 2}GaPt{sub 2} by the gallium atoms forming 4c(Ga-Pt-Ga-Pt) or by silicon atoms forming 2c(Si-Ir) bonds in Ca{sub 2}SiIr{sub 2}. The polyanion bonds to the europium (calcium) matrix via the pseudo lone-pairs at the gallium (silicon) atoms. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Improvenments in environmental trace analysis by GC-IR and LC-IR.

    NARCIS (Netherlands)

    Visser, T.; Vredenbregt, M.J.; Jong, A.P.J.M.; Somsen, G.W.; Hankemeier, T.; Velthorst, N.H.; Gooijer, C.; Brinkman, U.A.T.

    1997-01-01

    Research has been carried out to enlarge the potential of infrared (IR) spectrometry as a detector in gas and liquid chromatography (GC and LC). The study has been directed to applications in environmental analysis. Examples of recently obtained results are presented. The analyte detectability of

  3. 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.

  4. 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

  5. APPLICATION OF STANDARDIZED QUALITY CONTROL PROCEDURES TO OPEN-PATH FOURIER TRANSFORM INFRARED DATA COLLECTED AT A CONCENTRATED SWINE PRODUCTION FACILITY

    Science.gov (United States)

    Open-path Fourier transform infrared (OP/FT-IR) spectrometry was used to measure the concentrations of ammonia, methane, and other atmospheric eases at a concentrated swine production facility. A total of 2200 OP/FT-IR spectra were acquired along nine different monitoring paths d...

  6. Correcting the effect of refraction and dispersion of light in FT-IR spectroscopic imaging in transmission through thick infrared windows.

    Science.gov (United States)

    Chan, K L Andrew; Kazarian, Sergei G

    2013-01-15

    Transmission mode is one of the most common sampling methods for FT-IR spectroscopic imaging because the spectra obtained generally have a reasonable signal-to-noise ratio. However, dispersion and refraction of infrared light occurs when samples are sandwiched between infrared windows or placed underneath a layer of liquid. Dispersion and refraction cause infrared light to focus with different focal lengths depending on the wavelength (wavenumber) of the light. As a result, images obtained are in focus only at a particular wavenumber while they are defocused at other wavenumber values. In this work, a solution to correct this spread of focus by means of adding a lens on top of the infrared transparent window, such that a pseudo hemisphere is formed, has been investigated. Through this lens (or pseudo hemisphere), refraction of light is removed and the light across the spectral range has the same focal depth. Furthermore, the lens acts as a solid immersion objective and an increase of both magnification and spatial resolution (by 1.4 times) is demonstrated. The spatial resolution was investigated using an USAF resolution target, showing that the Rayleigh criterion can be achieved, as well as a sample with a sharp polymer interface to indicate the spatial resolution that can be expected in real samples. The reported approach was used to obtain chemical images of cross sections of cancer tissue and hair samples sandwiched between infrared windows showing the versatility and applicability of the method. In addition to the improved spatial resolution, the results reported herein also demonstrate that the lens can reduce the effect of scattering near the edges of tissue samples. The advantages of the presented approach, obtaining FT-IR spectroscopic images in transmission mode with the same focus across all wavenumber values and simultaneous improvement in spatial resolution, will have wide implications ranging from studies of live cells to sorption of drugs into tissues.

  7. Competing reaction channels in IR-laser-induced unimolecular reactions

    International Nuclear Information System (INIS)

    Berman, M.R.

    1981-01-01

    The competing reaction channels in the unimolecular decomposition of two molecules, formaldehyde and tetralin were studied. A TEA CO 2 laser was used as the excitation source in all experiments. The dissociation of D 2 CO was studied by infrared multiphoton dissociation (MPD) and the small-molecule nature of formaldehyde with regard to MPD was explored. The effect of collisions in MPD were probed by the pressure dependence of the MPD yield and ir fluorescence from multiphoton excited D 2 CO. MPD yield shows a near cubic dependence in pure D 2 CO which is reduced to a 1.7 power dependence when 15 torr of NO is added. The peak amplitude of 5 μm ir fluorescence from D 2 CO is proportional to the square of the D 2 CO pressure in pure D 2 CO or in the presence of 50 torr of Ar. Results are explained in terms of bottlenecks to excitation at the v = 1 level which are overcome by a combination of vibrational energy transfer and rotational relaxation. The radical/molecule branching ratio in D 2 CO MPD was 0.10 +- 0.02 at a fluence of 125 J/cm 2 at 946.0 cm -1 . The barrier height to molecular dissociation was calculated to be 3.6 +- 2.0 kcal/mole below the radical threshold or 85.0 +- 3.0 kcal/mole above the ground state of D 2 CO. In H 2 CO, this corresponds to 2.5 +- 2.0 kcal/mole below the radical threshold or 83.8 +- 3.0 kcal/mole above the ground state. Comparison with uv data indicate that RRKM theory is an acceptable description of formaldehyde dissociation in the 5 to 10 torr pressure range. The unimolecular decomposition of tetralin was studied by MPD and SiF 4 - sensitized pyrolysis. Both techniques induce decomposition without the interference of catalytic surfaces. Ethylene loss is identified as the lowest energy reaction channel. Dehydrogenation is found to result from step-wise H atom loss. Isomerization via disproportionation is also identified as a primary reaction channel

  8. HOMA1-IR and HOMA2-IR indexes in identifying insulin resistance and metabolic syndrome: Brazilian Metabolic Syndrome Study (BRAMS).

    Science.gov (United States)

    Geloneze, Bruno; Vasques, Ana Carolina Junqueira; Stabe, Christiane França Camargo; Pareja, José Carlos; Rosado, Lina Enriqueta Frandsen Paez de Lima; Queiroz, Elaine Cristina de; Tambascia, Marcos Antonio

    2009-03-01

    To investigate cut-off values for HOMA1-IR and HOMA2-IR to identify insulin resistance (IR) and metabolic syndrome (MS), and to assess the association of the indexes with components of the MS. Nondiabetic subjects from the Brazilian Metabolic Syndrome Study were studied (n = 1,203, 18 to 78 years). The cut-off values for IR were determined from the 90th percentile in the healthy group (n = 297) and, for MS, a ROC curve was generated for the total sample. In the healthy group, HOMA-IR indexes were associated with central obesity, triglycerides and total cholesterol (p 2.7 and HOMA2-IR > 1.8; and, for MS were: HOMA1-IR > 2.3 (sensitivity: 76.8%; specificity: 66.7%) and HOMA2-IR > 1.4 (sensitivity: 79.2%; specificity: 61.2%). The cut-off values identified for HOMA1-IR and HOMA2-IR indexes have a clinical and epidemiological application for identifying IR and MS in Westernized admixtured multi-ethnic populations.

  9. 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.

  10. OH/IR stars in the Galaxy

    International Nuclear Information System (INIS)

    Baud, B.

    1978-01-01

    Radio astronomical observations leading to the discovery of 71 OH/IR sources are described in this thesis. These OH/IR sources are characterized by their double peaked OH emission profile at a wavelength of 18 cm and by their strong IR infrared emission. An analysis of the distribution and radial velocities of a number of previously known and new OH/IR sources was performed. The parameter ΔV (the velocity separation between two emission peaks of the 18 cm line profile) was found to be a good criterion for a population classification with respect to stellar age

  11. The early phases of galaxy clusters formation in IR: coupling hydrodynamical simulations with GRASIL-3D

    Science.gov (United States)

    Granato, Gian Luigi; Ragone-Figueroa, Cinthia; Domínguez-Tenreiro, Rosa; Obreja, Aura; Borgani, Stefano; De Lucia, Gabriella; Murante, Giuseppe

    2015-06-01

    We compute and study the infrared and sub-mm properties of high-redshift (z ≳ 1) simulated clusters and protoclusters. The results of a large set of hydrodynamical zoom-in simulations including active galactic nuclei (AGN) feedback, have been treated with the recently developed radiative transfer code GRASIL-3D, which accounts for the effect of dust reprocessing in an arbitrary geometry. Here, we have slightly generalized the code to adapt it to the present purpose. Then we have post-processed boxes of physical size 2 Mpc encompassing each of the 24 most massive clusters identified at z = 0, at several redshifts between 0.5 and 3, producing IR and sub-mm mock images of these regions and spectral energy distributions (SEDs) of the radiation coming out from them. While this field is in its infancy from the observational point of view, rapid development is expected in the near future thanks to observations performed in the far-IR and sub-mm bands. Notably, we find that in this spectral regime our prediction are little affected by the assumption required by this post-processing, and the emission is mostly powered by star formation (SF) rather than accretion on to super massive black hole (SMBH). The comparison with the little observational information currently available, highlights that the simulated cluster regions never attain the impressive star formation rates suggested by these observations. This problem becomes more intriguing taking into account that the brightest cluster galaxies (BCGs) in the same simulations turn out to be too massive. It seems that the interplay between the feedback schemes and the star formation model should be revised, possibly incorporating a positive feedback mode.

  12. UV-IR mixing in nonassociative Snyder ϕ4 theory

    Science.gov (United States)

    Meljanac, Stjepan; Mignemi, Salvatore; Trampetic, Josip; You, Jiangyang

    2018-03-01

    Using a quantization of the nonassociative and noncommutative Snyder ϕ4 scalar field theory in a Hermitian realization, we present in this article analytical formulas for the momentum-conserving part of the one-loop two-point function of this theory in D -, 4-, and 3-dimensional Euclidean spaces, which are exact with respect to the noncommutative deformation parameter β . We prove that these integrals are regularized by the Snyder deformation. These results indicate that the Snyder deformation does partially regularize the UV divergences of the undeformed theory, as it was proposed decades ago. Furthermore, it is observed that different nonassociative ϕ4 products can generate different momentum-conserving integrals. Finally, most importantly, a logarithmic infrared divergence emerges in one of these interaction terms. We then analyze sample momentum nonconserving integral qualitatively and show that it could exhibit IR divergence too. Therefore, infrared divergences should exist, in general, in the Snyder ϕ4 theory. We consider infrared divergences at the limit p →0 as UV/IR mixings induced by nonassociativity, since they are associated to the matching UV divergence in the zero-momentum limit and appear in specific types of nonassociative ϕ4 products. We also discuss the extrapolation of the Snyder deformation parameter β to negative values as well as certain general properties of one-loop quantum corrections in Snyder ϕ4 theory at the zero-momentum limit.

  13. Application of Fourier-transform infrared (FT-IR) spectroscopy for simple and easy determination of chylomicron-triglyceride and very low density lipoprotein-triglyceride.

    Science.gov (United States)

    Sato, Kenichi; Seimiya, Masanori; Kodera, Yoshio; Kitamura, Akihide; Nomura, Fumio

    2010-02-01

    Fourier-transform infrared (FT-IR) spectroscopy is a simple and reagent-free physicochemical analysis method, and is a potential alternative to more time-consuming and labor-intensive procedures. In this study, we aimed to use FT-IR spectroscopy to determine serum concentrations of chylomicron-triglyceride (TG) and very low density lipoprotein (VLDL)-TG. We analyzed a chylomicron fraction and VLDL fraction, which had been obtained by ultracentrifugation, to search for wavelengths to designate to each fraction. Then, partial least square (PLS) calibrations were developed using a training set of samples, for which TG concentrations had been determined by conventional procedures. Validation was conducted with another set of samples using the PLS model to predict serum TG concentrations on the basis of the samples' IR spectra. We analyzed a total of 150 samples. Serum concentrations of chylomicron-TG and VLDL-TG estimated by FT-IR spectroscopy agreed well with those obtained by the reference method (r=0.97 for both lipoprotein fractions). FT-IR spectrometric analysis required 15mul of serum and was completed within 1min. Serum chylomicron-TG and VLDL-TG concentrations can be determined with FT-IR spectroscopy. This rapid and simple test may have a great impact on the management of patients with dyslipidemia. Copyright 2009. Published by Elsevier B.V.

  14. Mid-infrared integrated photonics on silicon: a perspective

    Directory of Open Access Journals (Sweden)

    Lin Hongtao

    2017-12-01

    Full Text Available The emergence of silicon photonics over the past two decades has established silicon as a preferred substrate platform for photonic integration. While most silicon-based photonic components have so far been realized in the near-infrared (near-IR telecommunication bands, the mid-infrared (mid-IR, 2–20-μm wavelength band presents a significant growth opportunity for integrated photonics. In this review, we offer our perspective on the burgeoning field of mid-IR integrated photonics on silicon. A comprehensive survey on the state-of-the-art of key photonic devices such as waveguides, light sources, modulators, and detectors is presented. Furthermore, on-chip spectroscopic chemical sensing is quantitatively analyzed as an example of mid-IR photonic system integration based on these basic building blocks, and the constituent component choices are discussed and contrasted in the context of system performance and integration technologies.

  15. Fourier transform infrared spectra applications to chemical systems

    CERN Document Server

    Ferraro, John R

    1978-01-01

    Fourier Transform Infrared Spectroscopy: Applications to Chemical Systems presents the chemical applications of the Fourier transform interferometry (FT-IR).The book contains discussions on the applications of FT-IR in the fields of chromatography FT-IR, polymers and biological macromolecules, emission spectroscopy, matrix isolation, high-pressure interferometry, and far infrared interferometry. The final chapter is devoted to the presentation of the use of FT-IR in solving national technical problems such as air pollution, space exploration, and energy related subjects.Researc

  16. Applications of Group Theory: Infrared and Raman Spectra of the Isomers of 1,2-Dichloroethylene: A Physical Experiment

    Science.gov (United States)

    Craig, Norman C.; Lacuesta, Nanette N.

    2004-01-01

    A study of the vibrational spectroscopy of the cis and trans isomers of 1,2-dichloroethylene provides an excellent opportunity to learn the applications group theory in laboratories. The necessity of using infrared (IR) spectroscopy and Raman spectroscopy in making full vibrational assignments is illustrated.

  17. Compact erbium lasers in the IR photorefractive keratectomy (PRK)

    Science.gov (United States)

    Liu, Baining; Eichler, Hans J.; Sperlich, O.; Holschbach, A.; Kayser, M.

    1996-09-01

    Erbium lasers deliver laser radiation near 3 micrometers and are a promising alternative to excimer laser photorefractive keratectomy (UV-PRK). In addition to easier handling due to all solid state technology, especially when operated in the fundamental mode, IR-PRK eliminates the potential of mutagenic side effects associated with UV-PRK. However, a successful IR-PRK for the clinic treatment in the near future demands both technological development of erbium lasers in different operation modes and clinical investigation of interaction between 3 micrometers radiation and human corneas. The excellent cooperation between university, company and hospital makes this possible. Uncoated thin plates made from infrared materials were found to be effective etalon reflectors with high damage threshold as high as 1 GW/cm2 for erbium lasers. Four kinds of such reflectors were successfully tested in Q-switched Er:YAG-laser at 2.94 micrometers and Er:Cr:YSGG-laser at 2.80 micrometers. Very stable operation of our erbium lasers with high output energy both in free-running and Q-switched modes is realized. First infrared photorefractive keratectomy (IR-PRK) for myopic correction in human corneas by a free-running erbium laser based on our new construction concepts was achieved.

  18. Higher-Order Scheme-Independent Series Expansions of $γ_{\\barψψ,IR}$ and $β'_{IR}$ in Conformal Field Theories

    DEFF Research Database (Denmark)

    Ryttov, Thomas A.; Shrock, Robert

    2017-01-01

    We study a vectorial asymptotically free gauge theory, with gauge group $G$ and $N_f$ massless fermions in a representation $R$ of this group, that exhibits an infrared (IR) zero in its beta function, $\\beta$, at the coupling $\\alpha=\\alpha_{IR}$ in the non-Abelian Coulomb phase. For general $G......_f$-dependent expansion variable. These are the highest orders to which these expansions have been calculated. We apply these general results to theories with $G={\\rm SU}(N_c)$ and $R$ equal to the fundamental, adjoint, and symmetric and antisymmetric rank-2 tensor representations. It is shown that for all...

  19. Nanoparticle Nucleation Is Termolecular in Metal and Involves Hydrogen: Evidence for a Kinetically Effective Nucleus of Three {Ir3H2x·P2W15Nb3O62}6- in Ir(0)n Nanoparticle Formation From [(1,5-COD)IrI·P2W15Nb3O62]8- Plus Dihydrogen.

    Science.gov (United States)

    Özkar, Saim; Finke, Richard G

    2017-04-19

    The nucleation process yielding Ir(0) ∼300 nanoparticles from (Bu 4 N) 5 Na 3 [(1,5-COD)Ir·P 2 W 15 Nb 3 O 62 ] (abbreviated hereafter as (COD)Ir·POM 8- , where POM 9- = the polyoxometalate, P 2 W 15 Nb 3 O 62 9- ) under H 2 is investigated to learn the true molecularity, and hence the associated kinetically effective nucleus (KEN), for nanoparticle formation for the first time. Recent work with this prototype transition-metal nanoparticle formation system ( J. Am. Chem. Soc. 2014 , 136 , 17601 - 17615 ) revealed that nucleation in this system is an apparent second-order in the precatalyst, A = (COD)Ir·POM 8- , not the higher order implied by classic nucleation theory and its nA ⇌ A n , "critical nucleus", A n concept. Herein, the three most reasonable more intimate mechanisms of nucleation are tested: bimolecular nucleation, termolecular nucleation, and a mechanism termed "alternative termolecular nucleation" in which 2(COD)Ir + and 1(COD)Ir·POM 8- yield the transition state of the rate-determining step of nucleation. The results obtained definitively rule out a simple bimolecular nucleation mechanism and provide evidence for the alternative termolecular mechanism with a KEN of 3, Ir 3 . All higher molecularity nucleation mechanisms were also ruled out. Further insights into the KEN and its more detailed composition involving hydrogen, {Ir 3 H 2x POM} 6- , are also obtained from the established role of H 2 in the Ir(0) ∼300 formation balanced reaction stoichiometry, from the p(H 2 ) dependence of the kinetics, and from a D 2 /H 2 kinetic isotope effect of 1.2(±0.3). Eight insights and conclusions are presented. A section covering caveats in the current work, and thus needed future studies, is also included.

  20. Conceptual thermal design and analysis of a far-infrared/mid-infrared remote sensing instrument

    Science.gov (United States)

    Roettker, William A.

    1992-07-01

    This paper presents the conceptual thermal design and analysis results for the Spectroscopy of the Atmosphere using Far-Infrared Emission (SAFIRE) instrument. SAFIRE has been proposed for Mission to Planet Earth to study ozone chemistry in the middle atmosphere using remote sensing of the atmosphere in the far-infrared (21-87 microns) and mid-infrared (9-16 microns) spectra. SAFIRE requires that far-IR detectors be cooled to 3-4 K and mid-IR detectors to 80 K for the expected mission lifetime of five years. A superfluid helium dewar and Stirling-cycle cryocoolers provide the cryogenic temperatures required by the infrared detectors. The proposed instrument thermal design uses passive thermal control techniques to reject 465 watts of waste heat from the instrument.

  1. Iterative random vs. Kennard-Stone sampling for IR spectrum-based classification task using PLS2-DA

    Science.gov (United States)

    Lee, Loong Chuen; Liong, Choong-Yeun; Jemain, Abdul Aziz

    2018-04-01

    External testing (ET) is preferred over auto-prediction (AP) or k-fold-cross-validation in estimating more realistic predictive ability of a statistical model. With IR spectra, Kennard-stone (KS) sampling algorithm is often used to split the data into training and test sets, i.e. respectively for model construction and for model testing. On the other hand, iterative random sampling (IRS) has not been the favored choice though it is theoretically more likely to produce reliable estimation. The aim of this preliminary work is to compare performances of KS and IRS in sampling a representative training set from an attenuated total reflectance - Fourier transform infrared spectral dataset (of four varieties of blue gel pen inks) for PLS2-DA modeling. The `best' performance achievable from the dataset is estimated with AP on the full dataset (APF, error). Both IRS (n = 200) and KS were used to split the dataset in the ratio of 7:3. The classic decision rule (i.e. maximum value-based) is employed for new sample prediction via partial least squares - discriminant analysis (PLS2-DA). Error rate of each model was estimated repeatedly via: (a) AP on full data (APF, error); (b) AP on training set (APS, error); and (c) ET on the respective test set (ETS, error). A good PLS2-DA model is expected to produce APS, error and EVS, error that is similar to the APF, error. Bearing that in mind, the similarities between (a) APS, error vs. APF, error; (b) ETS, error vs. APF, error and; (c) APS, error vs. ETS, error were evaluated using correlation tests (i.e. Pearson and Spearman's rank test), using series of PLS2-DA models computed from KS-set and IRS-set, respectively. Overall, models constructed from IRS-set exhibits more similarities between the internal and external error rates than the respective KS-set, i.e. less risk of overfitting. In conclusion, IRS is more reliable than KS in sampling representative training set.

  2. Progress on type-II InAs/GaSb superlattice (T2SL) infrared photodetector : from MWIR to VLWIR spectral domains

    Science.gov (United States)

    Christol, P.; Rodriguez, J.-B.

    2017-11-01

    Infrared photodetectors based on type-II InAs/GaSb superlattice (T2SL) material has been given a lot of attention this past decade, in particular by U.S. laboratories. Among the advantages of this material system, one can cite the possibility to span a large Infrared (IR) range (3μm to 30 μm) by tailoring the band-gap independently from the lattice constant, allowing addressing many applications by the same fabrication process and the realization of multi-color IR sensors for high performance imaging systems. Recently, the maturity of the growth of the quantum structure by molecular beam epitaxy (MBE) and progress on the processing resulted in the demonstration of high-performance mega-pixel focal plane arrays (FPA) in both the mid-wavelength (MWIR) and the long-wavelength (LWIR) infrared spectral bands [1]. Consequently, InAs/GaSb T2SL photodetector can be now considered as a new infrared technology which can be complementary to InSb, MCT or QWIPs technologies. After some reminders on InAs/GaSb T2SL quantum structure properties, we present in this communication the results obtained by the IES laboratory, from Montpellier University, France, for photodiodes operating in the MWIR spectral domains. We then complete the paper by the main results reached by others laboratories for T2SL detectors operating from MWIR to VLWIR spectral ranges.

  3. Data in support of FSH induction of IRS-2 in human granulosa cells: Mapping the transcription factor binding sites in human IRS-2 promoter

    Directory of Open Access Journals (Sweden)

    Surleen Kaur

    2016-03-01

    Full Text Available Insulin receptor substrate-2 (IRS-2 plays critical role in the regulation of various metabolic processes by insulin and IGF-1. The defects in its expression and/or function are linked to diseases like polycystic ovary syndrome (PCOS, insulin resistance and cancer. To predict the transcription factors (TFs responsible for the regulation of human IRS-2 gene expression, the transcription factor binding sites (TFBS and the corresponding TFs were investigated by analysis of IRS-2 promoter sequence using MatInspector Genomatix software (Cartharius et al., 2005 [1]. The ibid data is part of author׳s publication (Anjali et al., 2015 [2] that explains Follicle stimulating hormone (FSH mediated IRS-2 promoter activation in human granulosa cells and its importance in the pathophysiology of PCOS. Further analysis was carried out for binary interactions of TF regulatory genes in IRS-2 network using Cytoscape software tool and R-code. In this manuscript, we describe the methodology used for the identification of TFBSs in human IRS-2 promoter region and provide details on experimental procedures, analysis method, validation of data and also the raw files. The purpose of this article is to provide the data on all TFBSs in the promoter region of human IRS-2 gene as it has the potential for prediction of the regulation of IRS-2 gene in normal or diseased cells from patients with metabolic disorders and cancer. Keywords: IRS-2, TFBS, FSH, SP1, ChIP

  4. Solution processed Cu2SnS3 thin films for visible and infrared photodetector applications

    Directory of Open Access Journals (Sweden)

    Sandra Dias

    2016-02-01

    Full Text Available The Cu2SnS3 thin films were deposited using an economic, solution processible, spin coating technique. The films were found to possess a tetragonal crystal structure using X-ray diffraction. The film morphology and the particle size were determined using scanning electron microscopy. The various planes in the crystal were observed using transmission electron microscopy. The optimum band gap of 1.23 eV and a high absorption coefficient of 104 cm−1 corroborate its application as a photoactive material. The visible and infrared (IR photo response was studied for various illumination intensities. The current increased by one order from a dark current of 0.31 μA to a current of 1.78 μA at 1.05 suns and 8.7 μA under 477.7 mW/cm2 IR illumination intensity, at 3 V applied bias. The responsivity, sensitivity, external quantum efficiency and specific detectivity were found to be 10.93 mA/W, 5.74, 2.47% and 3.47 × 1010 Jones respectively at 1.05 suns and 16.32 mA/W, 27.16, 2.53% and 5.10 × 1010 Jones respectively at 477.7 mW/cm2 IR illumination. The transient photoresponse was measured both for visible and IR illuminations.

  5. A green approach to the production of 2-pyridone derivatives promoted by infrared irradiation

    International Nuclear Information System (INIS)

    Hernandez, F.; De la Cruz, F.; Lopez, J.; Pena, E.; Vazquez, M. A.; Delgado, F.; Alcaraz, Y.; FRobles, J.; Martinez A, M.

    2014-01-01

    An alternative is presented by promoting a reaction with infrared irradiation to obtain different 4-aryl-3-cyano-5-ethoxycarbonyl-6-methyl-2-pyridone derivatives 9 a-k. The process was carried out with a green approach from the corresponding 4 H-pyrans, using mild reaction conditions and infrared irradiation as the energy source. In the first stage, the reaction produced 1,2,3,4-tetrahydropyridine-2-one derivatives 8 a-k, followed by an oxidative step to afford the target molecules in good yields. The structure of products 9 a-k was confirmed by Ft-IR, 1 H NMR and 13 C NMR spectroscopic techniques and X-ray diffraction. It was found that the efficiency of the reaction depends on the catalyst and the solvent, as well as on the aldehyde substituents. (Author)

  6. Mid-infrared signatures of hydroxyl containing water clusters: Infrared laser Stark spectroscopy of OH–H{sub 2}O and OH(D{sub 2}O){sub n} (n = 1-3)

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Federico J. [Department of Chemistry, University of Georgia, Athens, Georgia 30602 (United States); INFIQC, Dpto. de Fisicoquímica, Facultad de Ciencias Químicas, Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón, X5000HUA Córdoba (Argentina); Brice, Joseph T.; Leavitt, Christopher M.; Liang, Tao; Douberly, Gary E., E-mail: douberly@uga.edu [Department of Chemistry, University of Georgia, Athens, Georgia 30602 (United States); Raston, Paul L. [Department of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia 22807 (United States); Pino, Gustavo A. [INFIQC, Dpto. de Fisicoquímica, Facultad de Ciencias Químicas, Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón, X5000HUA Córdoba (Argentina)

    2015-10-28

    Small water clusters containing a single hydroxyl radical are synthesized in liquid helium droplets. The OH–H{sub 2}O and OH(D{sub 2}O){sub n} clusters (n = 1-3) are probed with infrared laser spectroscopy in the vicinity of the hydroxyl radical OH stretch vibration. Experimental band origins are qualitatively consistent with ab initio calculations of the global minimum structures; however, frequency shifts from isolated OH are significantly over-predicted by both B3LYP and MP2 methods. An effective Hamiltonian that accounts for partial quenching of electronic angular momentum is used to analyze Stark spectra of the OH–H{sub 2}O and OH–D{sub 2}O binary complexes, revealing a 3.70(5) D permanent electric dipole moment. Computations of the dipole moment are in good agreement with experiment when large-amplitude vibrational averaging is taken into account. Polarization spectroscopy is employed to characterize two vibrational bands assigned to OH(D{sub 2}O){sub 2}, revealing two nearly isoenergetic cyclic isomers that differ in the orientation of the non-hydrogen-bonded deuterium atoms relative to the plane of the three oxygen atoms. The dipole moments for these clusters are determined to be approximately 2.5 and 1.8 D for “up-up” and “up-down” structures, respectively. Hydroxyl stretching bands of larger clusters containing three or more D{sub 2}O molecules are observed shifted approximately 300 cm{sup −1} to the red of the isolated OH radical. Pressure dependence studies and ab initio calculations imply the presence of multiple cyclic isomers of OH(D{sub 2}O){sub 3}.

  7. Quantification of water and silanol species on various silicas by coupling IR spectroscopy and in-situ thermogravimetry.

    Science.gov (United States)

    Gallas, Jean-Paul; Goupil, Jean-Michel; Vimont, Alexandre; Lavalley, Jean-Claude; Gil, Barbara; Gilson, Jean-Pierre; Miserque, Olivier

    2009-05-19

    Five silica samples (four precipitated silicas provided by commercial suppliers and one with the MCM-41 structure) have been studied by infrared spectroscopy and by a homemade thermogravimetry-infrared spectrum (TG-IR) setup. The silanol amount, accessibility to water, and different alcohols, and the affinity to water of these various silicas were compared and quantified. TG-IR measurements allowed the precise determination of the integrated molar absorption coefficient of the (nu+delta)OH band, epsilon(nu+delta)OH=(0.16+/-0.01) cm micromol(-1). It is independent of the sample origin and the concentration of silanol groups on silicas. For the precipitated dried samples evacuated at room temperature, the silanol concentration COH varies between 3.6 and 7.0 mmol g(-1). It is 5.3 mmol g(-1) in the case of the MCM-41 sample. Exchange experiments with D2O, followed by back-exchanges with different alcohols (methanol, propan-2-ol, 2-methyl-propan-2-ol, and 3-ethyl-pentan-3-ol) have been followed by infrared spectroscopy. All of the silanols of the MCM-41 sample are accessible to water and alcohol molecules. By contrast, about 20% of the silanols in precipitated samples are not exchanged by D2O (internal silanols). Accessibility decreases with alcohol size; the main effect is relative to methanol. Taking into account the sample specific surface areas and the silanol accessibility to D2O, the surface silanol density of precipitated silicas is close to 8 OH per nm2, at maximum coverage. At variance, the silanol surface density of the MCM silica is much lower, 4 OH per nm2. The TG-IR setup has also been used to determine the amount of water adsorbed on silicas through the intensity of the deltaH2O band. It varies linearly with the concentration of adsorbed water, whatever the silica sample. The integrated molar absorption coefficient of two bands, epsilondeltaH2O=(1.53+/-0.03) cm micromol(-1) and epsilon(nu+delta)H2O=(0.22+/-0.01) cm micromol(-1), have been determined. The

  8. Comparative investigation of Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD) in the determination of cotton fiber crystallinity.

    Science.gov (United States)

    Liu, Yongliang; Thibodeaux, Devron; Gamble, Gary; Bauer, Philip; VanDerveer, Don

    2012-08-01

    Despite considerable efforts in developing curve-fitting protocols to evaluate the crystallinity index (CI) from X-ray diffraction (XRD) measurements, in its present state XRD can only provide a qualitative or semi-quantitative assessment of the amounts of crystalline or amorphous fraction in a sample. The greatest barrier to establishing quantitative XRD is the lack of appropriate cellulose standards, which are needed to calibrate the XRD measurements. In practice, samples with known CI are very difficult to prepare or determine. In a previous study, we reported the development of a simple algorithm for determining fiber crystallinity information from Fourier transform infrared (FT-IR) spectroscopy. Hence, in this study we not only compared the fiber crystallinity information between FT-IR and XRD measurements, by developing a simple XRD algorithm in place of a time-consuming and subjective curve-fitting process, but we also suggested a direct way of determining cotton cellulose CI by calibrating XRD with the use of CI(IR) as references.

  9. Room temperature mid-IR single photon spectral imaging

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Tidemand-Lichtenberg, Peter; Pedersen, Christian

    2012-01-01

    Spectral imaging and detection of mid-infrared (mid-IR) wavelengths are emerging as an enabling technology of great technical and scientific interest; primarily because important chemical compounds display unique and strong mid-IR spectral fingerprints revealing valuable chemical information. Whi...... 20 % for polarized incoherent light at 3 \\mum. The proposed method is relevant for existing and new mid-IR applications like gas analysis and medical diagnostics....

  10. Effect of preservatives on the accuracy of mid-infrared milk component testing.

    Science.gov (United States)

    Barbano, D M; Wojciechowski, K L; Lynch, J M

    2010-12-01

    Our objective was to determine the effect of commonly used milk preservatives on the accuracy of fat, protein, and lactose content determination in milk by mid-infrared (mid-IR) milk analysis. Two producer raw milks (Holstein and Jersey) and 2 pasteurized modified milks, 1 similar to Holstein milk and 1 similar to Jersey milk were used as the 4 different milk sources. Seven different milk preservative approaches (K(2)Cr(2)O(7) and 6 different bronopol-based preservatives) and a portion of unpreserved milk for each of the 4 different milks sources were tested for fat B, lactose, protein, and fat A. The experiment was replicated 3 times (28 d each) for a total of 84 d. Two mid-infrared (mid-IR) transmittance milk analyzers (an optical and a virtual filter instrument) were used. A large batch of pilot milk was prepared from pasteurized, homogenized, unpreserved whole milk, split into vials, quick frozen by immersion in liquid nitrogen, and transferred into a -80 °C freezer. Pilots were thawed and analyzed on each testing day during the study. Significant increases were observed in all uncorrected readings on the pilot milks over the 84 d of the study, but the increases were gradual and small on each instrument for all components. Results from the study were corrected for these changes. A significant difference in mid-IR fat A readings was observed, whereas no differences were detected for fat B, lactose, or protein between unpreserved and preserved milks containing 0.02% K(2)Cr(2)O(7.) Therefore, K(2)Cr(2)O(7) has little or no effect on mid-IR test results. All bronopol-based preservative approaches in this study differed in mid-IR test results compared with K(2)Cr(2)O(7)-preserved and unpreserved milks, with the largest effect on protein results. Mid-IR uncorrected readings increased with time of refrigerated storage at 4°C for all preservative approaches, with the largest increase for protein. The rate of increase in uncorrected readings with time of storage was

  11. Optical Response of Cu1-xZnxIr2S4 Due to Metal--Insulator Transition

    International Nuclear Information System (INIS)

    Chen, L.; Matsunami, M.; Nanba, T.; Cao, G.; Suzuki, H.; Isobe, M.; Matsumoto, T.

    2003-01-01

    The mother material CuIr 2 S 4 of the thiospinel system Cu 1-x Zn x Ir 2 S 4 undergoes a temperature-induced metal--insulator (Mi) transition. We report the temperature dependence of the optical reflection spectra of Cu 1-x Zn x Ir 2 S 4 (x ≤ 0.5) at the temperatures of 8-300 K in the energy regions of 0.005--30 eV in order to study the change in the electronic structure due to the Zn substitution for Cu. Zn substitution induced mainly the splitting of the hybridization band between the Ir-5d(t 2g ) and S-3 p states crossing the E F . Obtained optical conductivity (σ ) spectrum is discussed in relation to the change in the electronic structure close to the E F . (author)

  12. N3 and O2 Protonated Tautomeric Conformations of 2 '-Deoxycytidine and Cytidine Coexist in the Gas Phase

    NARCIS (Netherlands)

    Wu, R.R.; Yang, B.; Frieler, C.E.; Berden, G.; Oomens, J.; Rodgers, M.T.

    2015-01-01

    Infrared multiple photon dissociation action spectra of the protonated forms of the cytidyl nucleosides, 2'-deoxycytidine, [dCyd+H](+), and cytidine, [Cyd+H](+), are acquired over the IR fingerprint and hydrogen-stretching regions. Electronic structure calculations are performed at the

  13. 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.

  14. 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.

  15. Yb-fiber-pumped mid-infrared picosecond optical parametric oscillator tunable across 6.2-6.7 µm

    Science.gov (United States)

    Kumar, S. Chaitanya; Casals, J. Canals; Parsa, S.; Zawilski, K. T.; Schunemann, P. G.; Ebrahim-Zadeh, M.

    2018-06-01

    We report a high-average-power picosecond optical parametric oscillator (OPO) tunable in the mid-infrared (mid-IR) based on CdSiP2 synchronously pumped by an Yb-fiber laser at 80 MHz repetition rate. Successful operation of this high-repetition-rate singly-resonant picosecond OPO has been enabled by the improved CSP crystal quality over a long interaction length. The OPO can be tuned across 1264-1284 nm in the near-IR signal and 6205-6724 nm in the mid-IR idler by temperature tuning the CSP crystal over 39-134 °C. By deploying a 5% output coupler for the resonant signal, we have extracted up to 44 mW of average power in the near-IR and up to 95 mW of non-resonant idler power at 6205 nm at 6.3% total conversion efficiency, with > 50 mW over > 55% of the mid-IR tuning range. We have investigated temperature-tuning characteristics of the OPO and compared the data with the theoretical calculations using the recent Sellmeier and thermo-optic coefficients for CdSiP2. The signal pulses from the OPO exhibit a Gaussian pulse duration of 19 ps centered at 1284 nm. We have also studied the output power stability of the OPO, resulting in a passive stability better than 1.9% rms for the near-IR signal and 2.4% rms for the mid-IR idler, measured over > 17 h, with both beams in high spatial quality.

  16. Infrared monitoring of combustion

    International Nuclear Information System (INIS)

    Bates, S.C.; Morrison, P.W. Jr.; Solomon, P.R.

    1991-01-01

    In this paper, the use of Fourier Transform Infrared (FT-IR) spectroscopy for combustion monitoring is described. A combination of emission, transmission, and reflection FT-IR spectroscopy yields data on the temperature and composition of the gases, surfaces and suspended particles in the combustion environment. Detection sensitivity of such trace exhaust gases as CO, CO 2 , SO 2 , NO x , and unburned hydrocarbons is at the ppm level. Tomographic reconstruction converts line-of-sight measurements into spatially resolved temperature and concentration data. Examples from various combustion processes are used to demonstrate the capabilities of the technique. Industrial measurements are described that have been performed directly in the combustion zone and in the exhaust duct of a large chemical recovery boiler. Other measurements of hot slag show how FT-IR spectroscopy can determine the temperature and optical properties of surfaces. In addition, experiments with water droplets show that transmission FT-IR data yield spectra that characterize particle size and number density

  17. Distinct signalling properties of insulin receptor substrate (IRS)-1 and IRS-2 in mediating insulin/IGF-1 action

    DEFF Research Database (Denmark)

    Rabiee, Atefeh; Krüger, Marcus; Ardenkjær-Larsen, Jacob

    2018-01-01

    Insulin/IGF-1 action is driven by a complex and highly integrated signalling network. Loss-of-function studies indicate that the major insulin/IGF-1 receptor substrate (IRS) proteins, IRS-1 and IRS-2, mediate different biological functions in vitro and in vivo, suggesting specific signalling...... properties despite their high degree of homology. To identify mechanisms contributing to the differential signalling properties of IRS-1 and IRS-2 in the mediation of insulin/IGF-1 action, we performed comprehensive mass spectrometry (MS)-based phosphoproteomic profiling of brown preadipocytes from wild type......, IRS-1-/-and IRS-2-/-mice in the basal and IGF-1-stimulated states. We applied stable isotope labeling by amino acids in cell culture (SILAC) for the accurate quantitation of changes in protein phosphorylation. We found ~10% of the 6262 unique phosphorylation sites detected to be regulated by IGF-1...

  18. Peeling of tomatoes using novel infrared radiation heating technology

    Science.gov (United States)

    The effectiveness of using infrared (IR) dry-peeling as an alternative process for peeling tomatoes without lye and water was studied. Compared to conventional lye peeling, IR dry-peeling using 30 s to 75 s heating time resulted in lower peeling loss (8.3% - 13.2% vs. 12.9% - 15.8%), thinner thickne...

  19. Efficient femtosecond mid-infrared pulse generation by dispersivewave radiation in bulk lithium niobate crystal

    DEFF Research Database (Denmark)

    Zhou, Binbin; Guo, Hairun; Bache, Morten

    2014-01-01

    We experimentally demonstrate efficient mid-infrared pulse generation by dispersive wave radiation in bulk lithium niobate crystal. Femtosecond mid-IR pulses centering from 2.8–2.92 µm are generated using the single pump wavelengths from 1.25–1.45 µm.......We experimentally demonstrate efficient mid-infrared pulse generation by dispersive wave radiation in bulk lithium niobate crystal. Femtosecond mid-IR pulses centering from 2.8–2.92 µm are generated using the single pump wavelengths from 1.25–1.45 µm....

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

    Science.gov (United States)

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

    2012-11-01

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

  1. Dual emitter IrQ(ppy)2 for OLED applications: Synthesis and spectroscopic analysis

    International Nuclear Information System (INIS)

    Ciobotaru, I.C.; Polosan, S.; Ciobotaru, C.C.

    2014-01-01

    The synthesis of organometallic compound with iridium and two types of ligands, quinoline and phenylpyridine, was done successfully. The absorption spectra of this compound have shown broad peaks in a visible region assigned to metal-to-ligands charge transfer and in UV region assigned to intraligand absorptions. The photoluminescence spectra exhibit dual character in which the red emission is more intense than the green one. In cathodoluminescence measurements, under electron beam, the powder obtained after recrystallization from dichloromethane, shows similar behaviors with photoluminescence spectra. The cathodoluminescence images have shown a luminescent crystalline powder with triclinic structure. This compound exhibits combined vibrational modes, which proves the presence in the same molecule of both ligands. Density Functional Theory calculation was involved in order to identify the main vibrations of this compound. Highlights: • Mixed-ligand of IrQ(ppy) 2 synthesis which gives green and red phosphorescence due to the MCLT processes coming from two types of ligands. • Absorption, photoluminescence, infrared spectroscopy and cathodoluminescence measurements for characterization of IrQ(ppy) 2 organometallic compound. • Experimental results have been compared with the output files obtained from Density Functional Theory by using the Gaussian 03W software

  2. Infrared Imaging for Inquiry-Based Learning

    Science.gov (United States)

    Xie, Charles; Hazzard, Edmund

    2011-01-01

    Based on detecting long-wavelength infrared (IR) radiation emitted by the subject, IR imaging shows temperature distribution instantaneously and heat flow dynamically. As a picture is worth a thousand words, an IR camera has great potential in teaching heat transfer, which is otherwise invisible. The idea of using IR imaging in teaching was first…

  3. Next-generation mid-infrared sources

    Science.gov (United States)

    Jung, D.; Bank, S.; Lee, M. L.; Wasserman, D.

    2017-12-01

    The mid-infrared (mid-IR) is a wavelength range with a variety of technologically vital applications in molecular sensing, security and defense, energy conservation, and potentially in free-space communication. The recent development and rapid commercialization of new coherent mid-infrared sources have spurred significant interest in the development of mid-infrared optical systems for the above applications. However, optical systems designers still do not have the extensive optical infrastructure available to them that exists at shorter wavelengths (for instance, in the visible and near-IR/telecom wavelengths). Even in the field of optoelectronic sources, which has largely driven the growing interest in the mid-infrared, the inherent limitations of state-of-the-art sources and the gaps in spectral coverage offer opportunities for the development of new classes of lasers, light emitting diodes and emitters for a range of potential applications. In this topical review, we will first present an overview of the current state-of-the-art mid-IR sources, in particular thermal emitters, which have long been utilized, and the relatively new quantum- and interband-cascade lasers, as well as the applications served by these sources. Subsequently, we will discuss potential mid-infrared applications and wavelength ranges which are poorly served by the current stable of mid-IR sources, with an emphasis on understanding the fundamental limitations of the current source technology. The bulk of the manuscript will then explore both past and recent developments in mid-infrared source technology, including narrow bandgap quantum well lasers, type-I and type-II quantum dot materials, type-II superlattices, highly mismatched alloys, lead-salts and transition-metal-doped II-VI materials. We will discuss both the advantages and limitations of each of the above material systems, as well as the potential new applications which they might serve. All in all, this topical review does not aim

  4. Distinct signalling properties of insulin receptor substrate (IRS)-1 and IRS-2 in mediating insulin/IGF-1 action.

    Science.gov (United States)

    Rabiee, Atefeh; Krüger, Marcus; Ardenkjær-Larsen, Jacob; Kahn, C Ronald; Emanuelli, Brice

    2018-07-01

    Insulin/IGF-1 action is driven by a complex and highly integrated signalling network. Loss-of-function studies indicate that the major insulin/IGF-1 receptor substrate (IRS) proteins, IRS-1 and IRS-2, mediate different biological functions in vitro and in vivo, suggesting specific signalling properties despite their high degree of homology. To identify mechanisms contributing to the differential signalling properties of IRS-1 and IRS-2 in the mediation of insulin/IGF-1 action, we performed comprehensive mass spectrometry (MS)-based phosphoproteomic profiling of brown preadipocytes from wild type, IRS-1 -/- and IRS-2 -/- mice in the basal and IGF-1-stimulated states. We applied stable isotope labeling by amino acids in cell culture (SILAC) for the accurate quantitation of changes in protein phosphorylation. We found ~10% of the 6262 unique phosphorylation sites detected to be regulated by IGF-1. These regulated sites included previously reported substrates of the insulin/IGF-1 signalling pathway, as well as novel substrates including Nuclear Factor I X and Semaphorin-4B. In silico prediction suggests the protein kinase B (PKB), protein kinase C (PKC), and cyclin-dependent kinase (CDK) as the main mediators of these phosphorylation events. Importantly, we found preferential phosphorylation patterns depending on the presence of either IRS-1 or IRS-2, which was associated with specific sets of kinases involved in signal transduction downstream of these substrates such as PDHK1, MAPK3, and PKD1 for IRS-1, and PIN1 and PKC beta for IRS-2. Overall, by generating a comprehensive phosphoproteomic profile from brown preadipocyte cells in response to IGF-1 stimulation, we reveal both common and distinct insulin/IGF-1 signalling events mediated by specific IRS proteins. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. ON INFRARED EXCESSES ASSOCIATED WITH Li-RICH K GIANTS

    Energy Technology Data Exchange (ETDEWEB)

    Rebull, Luisa M. [Spitzer Science Center (SSC) and Infrared Science Archive (IRSA), Infrared Processing and Analysis Center - IPAC, 1200 E. California Blvd., California Institute of Technology, Pasadena, CA 91125 (United States); Carlberg, Joleen K. [NASA Goddard Space Flight Center, Code 667, Greenbelt, MD 20771 (United States); Gibbs, John C.; Cashen, Sarah; Datta, Ashwin; Hodgson, Emily; Lince, Megan [Glencoe High School, 2700 NW Glencoe Rd., Hillsboro, OR 97124 (United States); Deeb, J. Elin [Bear Creek High School, 9800 W. Dartmouth Pl., Lakewood, CO 80227 (United States); Larsen, Estefania; Altepeter, Shailyn; Bucksbee, Ethan; Clarke, Matthew [Millard South High School, 14905 Q St., Omaha, NE 68137 (United States); Black, David V., E-mail: rebull@ipac.caltech.edu [Walden School of Liberal Arts, 4230 N. University Ave., Provo, UT 84604 (United States)

    2015-10-15

    Infrared (IR) excesses around K-type red giants (RGs) have previously been discovered using Infrared Astronomy Satellite (IRAS) data, and past studies have suggested a link between RGs with overabundant Li and IR excesses, implying the ejection of circumstellar shells or disks. We revisit the question of IR excesses around RGs using higher spatial resolution IR data, primarily from the Wide-field Infrared Survey Explorer. Our goal was to elucidate the link between three unusual RG properties: fast rotation, enriched Li, and IR excess. Our sample of RGs includes those with previous IR detections, a sample with well-defined rotation and Li abundance measurements with no previous IR measurements, and a large sample of RGs asserted to be Li-rich in the literature; we have 316 targets thought to be K giants, about 40% of which we take to be Li-rich. In 24 cases with previous detections of IR excess at low spatial resolution, we believe that source confusion is playing a role, in that either (a) the source that is bright in the optical is not responsible for the IR flux, or (b) there is more than one source responsible for the IR flux as measured in IRAS. We looked for IR excesses in the remaining sources, identifying 28 that have significant IR excesses by ∼20 μm (with possible excesses for 2 additional sources). There appears to be an intriguing correlation in that the largest IR excesses are all in Li-rich K giants, though very few Li-rich K giants have IR excesses (large or small). These largest IR excesses also tend to be found in the fastest rotators. There is no correlation of IR excess with the carbon isotopic ratio, {sup 12}C/{sup 13}C. IR excesses by 20 μm, though relatively rare, are at least twice as common among our sample of Li-rich K giants. If dust shell production is a common by-product of Li enrichment mechanisms, these observations suggest that the IR excess stage is very short-lived, which is supported by theoretical calculations. Conversely, the

  6. THE GREAT OBSERVATORIES ALL-SKY LIRG SURVEY: COMPARISON OF ULTRAVIOLET AND FAR-INFRARED PROPERTIES

    International Nuclear Information System (INIS)

    Howell, Justin H.; Armus, Lee; Surace, Jason A.; Petric, Andreea; Bridge, Carrie; Haan, Sebastian; Inami, Hanae; Mazzarella, Joseph M.; Chan, Ben H. P.; Madore, Barry F.; Evans, Aaron S.; Kim, Dong-Chan; Sanders, David B.; Appleton, Phil; Frayer, David T.; Lord, Steven; Schulz, Bernhard; Bothun, Greg; Charmandaris, Vassilis; Melbourne, Jason

    2010-01-01

    The Great Observatories All-sky LIRG Survey (GOALS) consists of a complete sample of 202 luminous infrared galaxies (LIRGs) selected from the IRAS Revised Bright Galaxy Sample (RBGS). The galaxies span the full range of interaction stages, from isolated galaxies to interacting pairs to late stage mergers. We present a comparison of the UV and infrared properties of 135 galaxies in GOALS observed by GALEX and Spitzer. For interacting galaxies with separations greater than the resolution of GALEX and Spitzer (∼2''-6''), we assess the UV and IR properties of each galaxy individually. The contribution of the FUV to the measured star formation rate (SFR) ranges from 0.2% to 17.9%, with a median of 2.8% and a mean of 4.0% ± 0.4%. The specific star formation rate (SSFR) of the GOALS sample is extremely high, with a median value (3.9 x 10 -10 yr -1 ) that is comparable to the highest SSFRs seen in the Spitzer Infrared Nearby Galaxies Survey sample. We examine the position of each galaxy on the IR excess-UV slope (IRX-β) diagram as a function of galaxy properties, including IR luminosity and interaction stage. The LIRGs on average have greater IR excesses than would be expected based on their UV colors if they obeyed the same relations as starbursts with L IR 11 L sun or normal late-type galaxies. The ratio of L IR to the value one would estimate from the IRX-β relation published for lower luminosity starburst galaxies ranges from 0.2 to 68, with a median value of 2.7. A minimum of 19% of the total IR luminosity in the RBGS is produced in LIRGs and ultraluminous infrared galaxies with red UV colors (β>0). Among resolved interacting systems, 32% contain one galaxy which dominates the IR emission while the companion dominates the UV emission. Only 21% of the resolved systems contain a single galaxy which dominates both wavelengths.

  7. The infrared luminosity function of AKARI 90 μm galaxies in the local Universe

    Science.gov (United States)

    Kilerci Eser, Ece; Goto, Tomotsugu

    2018-03-01

    Local infrared (IR) luminosity functions (LFs) are necessary benchmarks for high-redshift IR galaxy evolution studies. Any accurate IR LF evolution studies require accordingly accurate local IR LFs. We present IR galaxy LFs at redshifts of z ≤ 0.3 from AKARI space telescope, which performed an all-sky survey in six IR bands (9, 18, 65, 90, 140, and 160 μm) with 10 times better sensitivity than its precursor Infrared Astronomical Satellite. Availability of 160 μm filter is critically important in accurately measuring total IR luminosity of galaxies, covering across the peak of the dust emission. By combining data from Wide-field Infrared Survey Explorer (WISE), Sloan Digital Sky Survey (SDSS) Data Release 13 (DR 13), six-degree Field Galaxy Survey and the 2MASS Redshift Survey, we created a sample of 15 638 local IR galaxies with spectroscopic redshifts, factor of 7 larger compared to previously studied AKARI-SDSS sample. After carefully correcting for volume effects in both IR and optical, the obtained IR LFs agree well with previous studies, but comes with much smaller errors. Measured local IR luminosity density is ΩIR = 1.19 ± 0.05 × 108L⊙ Mpc-3. The contributions from luminous IR galaxies and ultraluminous IR galaxies to ΩIR are very small, 9.3 per cent and 0.9 per cent, respectively. There exists no future all-sky survey in far-IR wavelengths in the foreseeable future. The IR LFs obtained in this work will therefore remain an important benchmark for high-redshift studies for decades.

  8. Forensic Drug Identification, Confirmation, and Quantification Using Fully Integrated Gas Chromatography with Fourier Transform Infrared and Mass Spectrometric Detection (GC-FT-IR-MS).

    Science.gov (United States)

    Lanzarotta, Adam; Lorenz, Lisa; Voelker, Sarah; Falconer, Travis M; Batson, JaCinta S

    2018-05-01

    This manuscript is a continuation of a recent study that described the use of fully integrated gas chromatography with direct deposition Fourier transform infrared detection and mass spectrometric detection (GC-FT-IR-MS) to identify and confirm the presence of sibutramine and AB-FUBINACA. The purpose of the current study was to employ the GC-FT-IR portion of the same instrument to quantify these compounds, thereby demonstrating the ability to identify, confirm, and quantify drug substances using a single GC-FT-IR-MS unit. The performance of the instrument was evaluated by comparing quantitative analytical figures of merit to those measured using an established, widely employed method for quantifying drug substances, high performance liquid chromatography with ultraviolet detection (HPLC-UV). The results demonstrated that GC-FT-IR was outperformed by HPLC-UV with regard to sensitivity, precision, and linear dynamic range (LDR). However, sibutramine and AB-FUBINACA concentrations measured using GC-FT-IR were not significantly different at the 95% confidence interval compared to those measured using HPLC-UV, which demonstrates promise for using GC-FT-IR as a semi-quantitative tool at the very least. The most significant advantage of GC-FT-IR compared to HPLC-UV is selectivity; a higher level of confidence regarding the identity of the analyte being quantified is achieved using GC-FT-IR. Additional advantages of using a single GC-FT-IR-MS instrument for identification, confirmation, and quantification are efficiency, increased sample throughput, decreased consumption of laboratory resources (solvents, chemicals, consumables, etc.), and thus cost.

  9. Lanthanide-organic frameworks constructed from multi-functional ligands: Syntheses, structures, near-infrared and visible photoluminescence properties

    International Nuclear Information System (INIS)

    Li Xinfa; Xie Zailai; Lin Jingxiang; Cao Rong

    2009-01-01

    A series of multi-functional ligands supported lanthanide-organic frameworks, formulated as [Ln(HL 1 )(H 2 L 2 ) 0.5 (H 4 L 2 ) 0.5 (H 2 O)].(H 2 O) 1.5 .{Ln=La (1), Pr (2), Nd (3), Sm (4), Eu (5); H 3 L 1 =5-Sulfosaclicylic acid; H 4 L 2 =N,N'-piperazine (bis-methylene phosphonic acid)}, have been synthesized by hydrothermal reactions. Single crystal X-ray diffractions and powder XRD patterns confirm they are isostructural. They feature 3D framework structures based on extension of a 'zigzag' inorganic chain by organic linkers. Moreover, the photoluminescence properties of 5 and 3 have been investigated, and they show strong solid-state emissions in the visible and near-infrared (IR) regions at room temperature. - Graphical abstract: Five multi-functional ligands supported 3D lanthanide-organic frameworks have been synthesized and structurally characterized. Compounds 5 and 3 displayed strong solid-state emissions in the visible and near-infrared region at room temperature.

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

    KAUST Repository

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

    2012-01-01

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

  11. NO Reactions Over Ir-Based Catalysts in the Presence of O2

    Directory of Open Access Journals (Sweden)

    Mingxin Guo

    2011-01-01

    Full Text Available The behaviour of a series of Ir-based catalysts supported on SiO2, ZSM-5 and γ-Al2O3 with various Ir loadings prepared by impregnation method was conducted by temperature programmed reaction (TPR technique. The result implies that NO is oxidized to NO2 while simultaneously being reduced to N2 or N2O in the NO reactions over iridium catalysts. The surface active phase over iridium catalysts that promote the NO reactions is IrO2. The catalytic activity increases with the increase of the Ir loading and support materials have a little effect on the catalytic activity. When the loading is less than 0.1%, the catalytic activity was found to be dependent on the nature of support materials and in order: Ir/ZSM-5>Ir/γ-Al2O3>Ir/SiO2. When the loading is higher than 0.1%, the catalytic activity for NO oxidation is in order: Ir/ZSM-5>Ir/SiO2>Ir/γ -Al2O3, which is correlated with Ir dispersion on the surface of support materials and the catalytic activity for NO reduction is in sequence: Ir/γ -Al2O3>Ir/SiO2>Ir/ZSM-5, which is attributed to the adsorbed-dissociation of NO2. Compared to Pt/γ-Al2O3, Ir/γ-Al2O3 catalyst is more benefit for the NO reduction.

  12. Synchrotron infrared spectromicroscopy as a novel bioanalytical microprobe for individual living cells: Cytotoxicity considerations

    Energy Technology Data Exchange (ETDEWEB)

    Holman, Hoi-Ying N.; Bjornstad, Kathleen A.; McNamara, Morgan P.; Martin, Michael C.; McKinney, Wayne R.; Blakely, Eleanor A.

    2001-12-12

    Synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectromicroscopy is a newly emerging analytical tool capable of monitoring the biochemistry within an individual living mammalian cell in real time. This unique technique provides infrared (IR)spectra, hence chemical information, with high signal-to-noise at spatial resolutions as fine as 3 to 10 microns. Mid-IR photons are too low in energy (0.05-0.5 eV) to either break bonds or to cause ionization, and the synchrotron IR beam has been shown to produce minimal sample heating. However, an important question remains, ''Does the intense synchrotron beam induce any cytotoxic effects in living cells?'' In this work, we present the results from a series of standard biological assays to evaluate any short-and/or long-term effects on cells exposed to the synchrotron radiation-based infrared (SR-IR) beam. Cell viability was tested using alcian blue dye-exclusion and colony formation assays. Cell-cycle progression was tested with bromodeoxyuridine (BrdU) uptake during DNA synthesis. Cell metabolism was tested using an 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. All control, 5-, 10-, and 20-minute SR-IR exposure tests (267 total and over 1000 controls) show no evidence of cytotoxic effects. Concurrent infrared spectra obtained with each experiment confirm no detectable chemistry changes between control and exposed cells.

  13. A green approach to the production of 2-pyridone derivatives promoted by infrared irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, F.; De la Cruz, F.; Lopez, J.; Pena, E.; Vazquez, M. A. [Universidad de Guanajuato, Dapartamento de Quimica, Noria Alta s/n, 36050 Guanajuato, Gto. (Mexico); Delgado, F. [IPN, Escuela Nacional de Ciencias Biologicas, Departamento de Quimica Organica, Prol. Carpio y Plan de Ayala s/n, 11340 Mexico D. F. (Mexico); Alcaraz, Y.; FRobles, J.; Martinez A, M., E-mail: mvazquez@ugto.mx [Universidad de Guanajuato, Departamento de Farmacia, Noria Alta s/n, 36050 Guanajuato, Gto. (Mexico)

    2014-10-01

    An alternative is presented by promoting a reaction with infrared irradiation to obtain different 4-aryl-3-cyano-5-ethoxycarbonyl-6-methyl-2-pyridone derivatives 9 a-k. The process was carried out with a green approach from the corresponding 4 H-pyrans, using mild reaction conditions and infrared irradiation as the energy source. In the first stage, the reaction produced 1,2,3,4-tetrahydropyridine-2-one derivatives 8 a-k, followed by an oxidative step to afford the target molecules in good yields. The structure of products 9 a-k was confirmed by Ft-IR, {sup 1}H NMR and {sup 13}C NMR spectroscopic techniques and X-ray diffraction. It was found that the efficiency of the reaction depends on the catalyst and the solvent, as well as on the aldehyde substituents. (Author)

  14. Hybridization Gap and Dresselhaus Spin Splitting in EuIr4In2Ge4.

    Science.gov (United States)

    Calta, Nicholas P; Im, Jino; Rodriguez, Alexandra P; Fang, Lei; Bugaris, Daniel E; Chasapis, Thomas C; Freeman, Arthur J; Kanatzidis, Mercouri G

    2015-08-03

    EuIr4In2Ge4 is a new intermetallic semiconductor that adopts a non-centrosymmetric structure in the tetragonal I4̄2m space group with unit cell parameters a=6.9016(5) Å and c=8.7153(9) Å. The compound features an indirect optical band gap E(g)=0.26(2) eV, and electronic-structure calculations show that the energy gap originates primarily from hybridization of the Ir 5d orbitals, with small contributions from the Ge 4p and In 5p orbitals. The strong spin-orbit coupling arising from the Ir atoms, and the lack of inversion symmetry leads to significant spin splitting, which is described by the Dresselhaus term, at both the conduction- and valence-band edges. The magnetic Eu(2+) ions present in the structure, which do not play a role in gap formation, order antiferromagnetically at 2.5 K. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. THE STUDY OF CLINOPTILOLITE MODIFIED WITH3d METALS HALIDES BY IR AND DIFFUSE REFLECTANCE SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    T. L. Rakitskaya

    2015-11-01

    Full Text Available The results of investigation of natural clinoptilolite (N-CLI and that modified with 3d metal halides (MeCl2/N-CLI, where Me are Cu, Co, and Mn by IR and diffuse reflectance spectroscopy are summarized. A band at 3437 cm-1 assigned to stretching vibrations of hydroxyl groups (nOH is found in the IR spectrum of the N-CLI sample. A location of the band was practically the same as for all above MeCl2/N-CLI samples. A band of middle intensity at 1638 cm-1 in the range of deformation vibrations of zeolite water observed in the IR spectrum of N-CLI slightly displays to lower frequencies in the case of the modified samples. An intensive wide band of a complex shape in the range from 1250 to 980 cm-1 assigned to Si–O–Si and Si–O–Al vibrations appears in IR spectra of all samples. A doublet band of middle intensity at 797 and 778 cm-1 is assigned to external symmetric stretching T-O vibrations and a band at 606 cm-1-to vibrations of a double ring. A location of the above bands is the same for all listed samples but their intensity is higher for MnCl2/N-CLI and CoCl2/N-CLI samples. After the reaction with ozone, significant changes in the IR spectra are observed only for MnCl2/N-CLI. They are due to MnO2 formation on the clinoptilolite surface resulting in a high frequency displacement of some bands. Based on UV-vi spectroscopy results, it is reasonable to make conclusions about the coordination and valence state of a central atom in the MeCl2/N-CLI samples under study. A location of charge transfer bands for these samples only slightly differs from that for N-CLI however the intensity of such bands increases for the MeCl2/N-CLI samples. The UV-vis spectrum of MnCl2/N-CLI changes after the reaction with ozone: the appearance of new bands of  charge transfer at 363 and 354 nm and also the two-fold increase in intensity of a charge transfer band at 272 nm in comparison with those of N-CLI and MnCl2/N-CLI are the evidence of change in both the

  16. Rapid Visualization of Human Tumor Xenografts through Optical Imaging with a Near-Infrared Fluorescent Anti–Epidermal Growth Factor Receptor Nanobody

    Directory of Open Access Journals (Sweden)

    Sabrina Oliveira

    2012-01-01

    Full Text Available Given that overexpression of the epidermal growth factor receptor (EGFR is found in many types of human epithelial cancers, noninvasive molecular imaging of this receptor is of great interest. A number of studies have employed monoclonal antibodies as probes; however, their characteristic long half-life in the bloodstream has encouraged the development of smaller probes. In this study, an anti-EGFR nanobody-based probe was developed and tested in comparison with cetuximab for application in optical molecular imaging. To this aim, the anti-EGFR nanobody 7D12 and cetuximab were conjugated to the near-infrared fluorophore IRDye800CW. 7D12-IR allowed the visualization of tumors as early as 30 minutes postinjection, whereas with cetuximab-IR, no signal above background was observed at the tumor site. Quantification of the IR-conjugated proteins in the tumors revealed ≈ 17% of injected dose per gram 2 hours after injection of 7D12-IR, which was significantly higher than the tumor uptake obtained 24 hours after injection of cetuximab-IR. This difference is associated with the superior penetration and distribution of 7D12-IR within the tumor. These results demonstrate that this anti-EGFR nanobody conjugated to the NIR fluorophore has excellent properties for rapid preclinical optical imaging, which holds promise for its future use as a complementary diagnostic tool in humans.

  17. DISCOVERING THE MISSING 2.2 < z < 3 QUASARS BY COMBINING OPTICAL VARIABILITY AND OPTICAL/NEAR-INFRARED COLORS

    International Nuclear Information System (INIS)

    Wu Xuebing; Wang Ran; Bian Fuyan; Jiang Linhua; Fan Xiaohui; Schmidt, Kasper B.

    2011-01-01

    The identification of quasars in the redshift range 2.2 < z < 3 is known to be very inefficient because the optical colors of such quasars are indistinguishable from those of stars. Recent studies have proposed using optical variability or near-infrared (near-IR) colors to improve the identification of the missing quasars in this redshift range. Here we present a case study combining both methods. We select a sample of 70 quasar candidates from variables in Sloan Digital Sky Survey (SDSS) Stripe 82, which are non-ultraviolet excess sources and have UKIDSS near-IR public data. They are clearly separated into two parts on the Y - K/g - z color-color diagram, and 59 of them meet or lie close to a newly proposed Y - K/g - z selection criterion for z < 4 quasars. Of these 59 sources, 44 were previously identified as quasars in SDSS DR7, and 35 of them are quasars at 2.2 < z < 3. We present spectroscopic observations of 14 of 15 remaining quasar candidates using the Bok 2.3 m telescope and the MMT 6.5 m telescope, and successfully identify all of them as new quasars at z = 2.36-2.88. We also apply this method to a sample of 643 variable quasar candidates with SDSS-UKIDSS nine-band photometric data selected from 1875 new quasar candidates in SDSS Stripe 82 given by Butler and Bloom based on the time-series selections, and find that 188 of them are probably new quasars with photometric redshifts at 2.2 < z < 3. Our results indicate that the combination of optical variability and optical/near-IR colors is probably the most efficient way to find 2.2 < z < 3 quasars and is very helpful for constructing a complete quasar sample. We discuss its implications for ongoing and upcoming large optical and near-IR sky surveys.

  18. Electrical and mechanical anharmonicities from NIR-VCD spectra of compounds exhibiting axial and planar chirality: the cases of (S)-2,3-pentadiene and methyl-d(3) (R)- and (S)-[2.2]paracyclophane-4-carboxylate.

    Science.gov (United States)

    Abbate, Sergio; Longhi, Giovanna; Gangemi, Fabrizio; Gangemi, Roberto; Superchi, Stefano; Caporusso, Anna Maria; Ruzziconi, Renzo

    2011-10-01

    The IR and Near infrared (NIR) vibrational circular dichroism (VCD) spectra of molecules endowed with noncentral chirality have been investigated. Data for fundamental, first, and second overtone regions of (S)-2,3-pentadiene, exhibiting axial chirality, and methyl-d(3) (R)- and (S)-[2.2]paracyclophane-4-carboxylate, exhibiting planar chirality have been measured and analyzed. The analysis of NIR and IR VCD spectra was based on the local-mode model and the use of density functional theory (DFT), providing mechanical and electrical anharmonic terms for all CH-bonds. The comparison of experimental and calculated spectra is satisfactory and allows one to monitor fine details in the asymmetric charge distribution in the molecules: these details consist in the harmonic frequencies, in the principal anharmonicity constants, in both the atomic polar and axial tensors and in their first and second derivatives with respect to the CH-stretching coordinates. Copyright © 2011 Wiley-Liss, Inc.

  19. Study of (n,2n reaction on 191,193Ir isotopes and isomeric cross section ratios

    Directory of Open Access Journals (Sweden)

    Vlastou R.

    2017-01-01

    Full Text Available The cross section of 191Ir(n,2n190Irg+m1 and 191Ir(n,2n190Irm2 reactions has been measured at 17.1 and 20.9 MeV neutron energies at the 5.5 MV tandem T11/25 Accelerator Laboratory of NCSR “Demokritos”, using the activation method. The neutron beams were produced by means of the 3H(d,n4He reaction at a flux of the order of 2 × 105 n/cm2s. The neutron flux has been deduced implementing the 27Al(n,α reaction, while the flux variation of the neutron beam was monitored by using a BF3 detector. The 193Ir(n,2n192Ir reaction cross section has also been determined, taking into account the contribution from the contaminant 191Ir(n,γ192Ir reaction. The correction method is based on the existing data in ENDF for the contaminant reaction, convoluted with the neutron spectra which have been extensively studied by means of simulations using the NeusDesc and MCNP codes. Statistical model calculations using the code EMPIRE 3.2.2 and taking into account pre-equilibrium emission, have been performed on the data measured in this work as well as on data reported in literature.

  20. Infrared Range Sensor Array for 3D Sensing in Robotic Applications

    Directory of Open Access Journals (Sweden)

    Yongtae Do

    2013-04-01

    Full Text Available This paper presents the design and testing of multiple infrared range detectors arranged in a two-dimensional (2D array. The proposed system can collect the sparse three-dimensional (3D data of objects and surroundings for robotics applications. Three kinds of tasks are considered using the system: detecting obstacles that lie ahead of a mobile robot, sensing the ground profile for the safe navigation of a mobile robot, and sensing the shape and position of an object on a conveyor belt for pickup by a robot manipulator. The developed system is potentially a simple alternative to high-resolution (and expensive 3D sensing systems, such as stereo cameras or laser scanners. In addition, the system can provide shape information about target objects and surroundings that cannot be obtained using simple ultrasonic sensors. Laboratory prototypes of the system were built with nine infrared range sensors arranged in a 3×3 array and test results confirmed the validity of system.

  1. 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.

  2. GOODS-HERSCHEL AND CANDELS: THE MORPHOLOGIES OF ULTRALUMINOUS INFRARED GALAXIES AT z ∼ 2

    International Nuclear Information System (INIS)

    Kartaltepe, Jeyhan S.; Dickinson, Mark; Alexander, David M.; Bell, Eric F.; Dahlen, Tomas; Lotz, Jennifer; Elbaz, David; Wiklind, Tommy; Faber, S. M.; Aussel, Herve; Bethermin, Matthieu; Bournaud, Frederic; Dannerbauer, Helmut; McIntosh, Daniel H.; Altieri, Bruno; Charmandaris, Vassilis; Conselice, Christopher J.; Cooray, Asantha; Davé, Romeel; Dunlop, James

    2012-01-01

    Using deep 100 and 160 μm observations in GOODS-South from GOODS-Herschel, combined with high-resolution HST/WFC3 near-infrared imaging from CANDELS, we present the first detailed morphological analysis of a complete, far-infrared (FIR) selected sample of 52 ultraluminous infrared galaxies (ULIRGs; L IR > 10 12 L ☉ ) at z ∼ 2. We also make use of a comparison sample of galaxies with lower IR luminosities but with the same redshift and H-band magnitude distribution. Our visual classifications of these two samples indicate that the fractions of objects with disk and spheroid morphologies are roughly the same but that there are significantly more mergers, interactions, and irregular galaxies among the ULIRGs (72 +5 –7 % versus 32 ± 3%). The combination of disk and irregular/interacting morphologies suggests that early-stage interactions, minor mergers, and disk instabilities could play an important role in ULIRGs at z ∼ 2. We compare these fractions with those of a z ∼ 1 sample selected from GOODS-H and COSMOS across a wide luminosity range and find that the fraction of disks decreases systematically with L IR while the fraction of mergers and interactions increases, as has been observed locally. At comparable luminosities, the fraction of ULIRGs with various morphological classifications is similar at z ∼ 2 and z ∼ 1, though there are slightly fewer mergers and slightly more disks at higher redshift. We investigate the position of the z ∼ 2 ULIRGs, along with 70 z ∼ 2 LIRGs, on the specific star formation rate versus redshift plane, and find 52 systems to be starbursts (i.e., they lie more than a factor of three above the main-sequence relation). We find that many of these systems are clear interactions and mergers (∼50%) compared to only 24% of systems on the main sequence relation. If irregular disks are included as potential minor mergers, then we find that up to ∼73% of starbursts are involved in a merger or interaction at some level

  3. GOODS-HERSCHEL AND CANDELS: THE MORPHOLOGIES OF ULTRALUMINOUS INFRARED GALAXIES AT z {approx} 2

    Energy Technology Data Exchange (ETDEWEB)

    Kartaltepe, Jeyhan S.; Dickinson, Mark [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Alexander, David M. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 (United States); Dahlen, Tomas; Lotz, Jennifer [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Elbaz, David; Wiklind, Tommy [Joing ALMA Observatory, ESO, Santiago (Chile); Faber, S. M.; Aussel, Herve; Bethermin, Matthieu; Bournaud, Frederic; Dannerbauer, Helmut [Laboratoire AIM-Paris-Saclay, CEA/DSM/Irfu-CNRS-Universite Paris Diderot, CE-Saclay, F-91191 Gif-sur-Yvette (France); McIntosh, Daniel H. [University of California Observatories/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Altieri, Bruno [Herschel Science Centre, European Space Astronomy Centre, Villanueva de la Canada, E-28691 Madrid (Spain); Charmandaris, Vassilis [Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, GR-71003 Heraklion (Greece); Conselice, Christopher J. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Cooray, Asantha [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Dave, Romeel [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Dunlop, James, E-mail: jeyhan@noao.edu [Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); and others

    2012-09-20

    Using deep 100 and 160 {mu}m observations in GOODS-South from GOODS-Herschel, combined with high-resolution HST/WFC3 near-infrared imaging from CANDELS, we present the first detailed morphological analysis of a complete, far-infrared (FIR) selected sample of 52 ultraluminous infrared galaxies (ULIRGs; L{sub IR} > 10{sup 12} L{sub Sun }) at z {approx} 2. We also make use of a comparison sample of galaxies with lower IR luminosities but with the same redshift and H-band magnitude distribution. Our visual classifications of these two samples indicate that the fractions of objects with disk and spheroid morphologies are roughly the same but that there are significantly more mergers, interactions, and irregular galaxies among the ULIRGs (72{sup +5}{sub -7}% versus 32 {+-} 3%). The combination of disk and irregular/interacting morphologies suggests that early-stage interactions, minor mergers, and disk instabilities could play an important role in ULIRGs at z {approx} 2. We compare these fractions with those of a z {approx} 1 sample selected from GOODS-H and COSMOS across a wide luminosity range and find that the fraction of disks decreases systematically with L{sub IR} while the fraction of mergers and interactions increases, as has been observed locally. At comparable luminosities, the fraction of ULIRGs with various morphological classifications is similar at z {approx} 2 and z {approx} 1, though there are slightly fewer mergers and slightly more disks at higher redshift. We investigate the position of the z {approx} 2 ULIRGs, along with 70 z {approx} 2 LIRGs, on the specific star formation rate versus redshift plane, and find 52 systems to be starbursts (i.e., they lie more than a factor of three above the main-sequence relation). We find that many of these systems are clear interactions and mergers ({approx}50%) compared to only 24% of systems on the main sequence relation. If irregular disks are included as potential minor mergers, then we find that up to {approx

  4. Communication: IR spectroscopy of neutral transition metal clusters through thermionic emission

    NARCIS (Netherlands)

    Lapoutre, V. J. F.; Haertelt, M.; Meijer, G.; Fielicke, A.; Bakker, J. M.

    2013-01-01

    The resonant multiple photon excitation of neutral niobium clusters using tunable infrared (IR) radiation leads to thermionic emission. By measuring the mass-resolved ionization yield as a function of IR wavenumber species selective IR spectra are obtained for Nb-n (n = 5-20) over the 200-350 cm(-1)

  5. Modeling Microalgal Biosediment Formation Based on Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Monitoring.

    Science.gov (United States)

    Ogburn, Zachary L; Vogt, Frank

    2018-03-01

    With increasing amounts of anthropogenic pollutants being released into ecosystems, it becomes ever more important to understand their fate and interactions with living organisms. Microalgae play an important ecological role as they are ubiquitous in marine environments and sequester inorganic pollutants which they transform into organic biomass. Of particular interest in this study is their role as a sink for atmospheric CO 2 , a greenhouse gas, and nitrate, one cause of harmful algal blooms. Novel chemometric hard-modeling methodologies have been developed for interpreting phytoplankton's chemical and physiological adaptations to changes in their growing environment. These methodologies will facilitate investigations of environmental impacts of anthropogenic pollutants on chemical and physiological properties of marine microalgae (here: Nannochloropsis oculata). It has been demonstrated that attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can gain insights into both and this study only focuses on the latter. From time-series of spectra, the rate of microalgal biomass settling on top of a horizontal ATR element is derived which reflects several of phytoplankton's physiological parameters such as growth rate, cell concentrations, cell size, and buoyancy. In order to assess environmental impacts on such parameters, microalgae cultures were grown under 25 different chemical scenarios covering 200-600 ppm atmospheric CO 2 and 0.35-0.75 mM dissolved NO 3 - . After recording time-series of ATR FT-IR spectra, a multivariate curve resolution-alternating least squares (MCR-ALS) algorithm extracted spectroscopic and time profiles from each data set. From the time profiles, it was found that in the considered concentration ranges only NO 3 - has an impact on the cells' physiological properties. In particular, the cultures' growth rate has been influenced by the ambient chemical conditions. Thus, the presented spectroscopic

  6. Combined MW-IR Precipitation Evolving Technique (PET of convective rain fields

    Directory of Open Access Journals (Sweden)

    F. Di Paola

    2012-11-01

    Full Text Available This paper describes a new multi-sensor approach for convective rain cell continuous monitoring based on rainfall derived from Passive Microwave (PM remote sensing from the Low Earth Orbit (LEO satellite coupled with Infrared (IR remote sensing Brightness Temperature (TB from the Geosynchronous (GEO orbit satellite. The proposed technique, which we call Precipitation Evolving Technique (PET, propagates forward in time and space the last available rain-rate (RR maps derived from Advanced Microwave Sounding Units (AMSU and Microwave Humidity Sounder (MHS observations by using IR TB maps of water vapor (6.2 μm and thermal-IR (10.8 μm channels from a Spinning Enhanced Visible and Infrared Imager (SEVIRI radiometer. PET is based on two different modules, the first for morphing and tracking rain cells and the second for dynamic calibration IR-RR. The Morphing module uses two consecutive IR data to identify the motion vector to be applied to the rain field so as to propagate it in time and space, whilst the Calibration module computes the dynamic relationship between IR and RR in order to take into account genesis, extinction or size variation of rain cells. Finally, a combination of the Morphing and Calibration output provides a rainfall map at IR space and time scale, and the whole procedure is reiterated by using the last RR map output until a new MW-based rainfall is available. The PET results have been analyzed with respect to two different PM-RR retrieval algorithms for seven case studies referring to different rainfall convective events. The qualitative, dichotomous and continuous assessments show an overall ability of this technique to propagate rain field at least for 2–3 h propagation time.

  7. Crystal structure of the Al2CuIr phase

    International Nuclear Information System (INIS)

    Meshi, L.; Ezersky, V.; Kapush, D.; Grushko, B.

    2010-01-01

    A new ternary Al 2 CuIr phase was revealed in the Al-Cu-Ir system. It is formed below 1063 o C from the β-phase (CsCl-type structure) extending at elevated temperatures from AlIr. The crystal structure of the Al 2 CuIr phase was determined using a combination of precession electron diffraction and X-ray powder diffraction techniques. The phase has an orthorhombic C-centered unit cell with lattice parameters a = 8.1196(7) A, b = 5.0646(2) A and c = 5.18513(3) A; its crystal symmetry can be described by the Cmme (no. 67) space group (Pearson symbol oC16). The unit cell of the new phase contains 8 Al, 4 Cu and 4 Ir atoms and exhibits a new structure type. The reliability factors characterizing the Rietveld refinement procedure are: R p = 4.45%, R wp = 6.45%, R B = 3.69% and R f = 2.41%.

  8. AGN Obscuration Through Dusty Infrared Dominated Flows. II. Multidimensional, Radiation-Hydrodynamics Modeling

    Science.gov (United States)

    Dorodnitsyn, Anton; Kallman, Tim; Bisno\\vatyiI-Kogan, Gennadyi

    2011-01-01

    We explore a detailed model in which the active galactic nucleus (AGN) obscuration results from the extinction of AGN radiation in a global ow driven by the pressure of infrared radiation on dust grains. We assume that external illumination by UV and soft X-rays of the dusty gas located at approximately 1pc away from the supermassive black hole is followed by a conversion of such radiation into IR. Using 2.5D, time-dependent radiation hydrodynamics simulations in a ux-limited di usion approximation we nd that the external illumination can support a geometrically thick obscuration via out ows driven by infrared radiation pressure in AGN with luminosities greater than 0:05 L(sub edd) and Compton optical depth, Tau(sub T) approx > & 1.

  9. Multi-pollutants sensors based on near-IR telecom lasers and mid-IR difference frequency generation: development and applications

    International Nuclear Information System (INIS)

    Cousin, J.

    2006-12-01

    At present the detection of VOC and other anthropic trace pollutants is an important challenge in the measurement of air quality. Infrared spectroscopy, allowing spectral regions rich in molecular absorption to be probed, is a suitable technique for in-situ monitoring of the air pollution. Thus the aim of this work was to develop instruments capable of detecting multiple pollutants for in-situ monitoring by IR spectroscopy. A first project benefited from the availability of the telecommunications lasers emitting in near-IR. This instrument was based on an external cavity diode laser (1500 - 1640 nm) in conjunction with a multipass cell (100 m). The detection sensitivity was optimised by employing a balanced detection and a sweep integration procedure. The instrument developed is deployable for in-situ measurements with a sensitivity of -8 cm -1 Hz -1/2 and allowed the quantification of chemical species such as CO 2 , CO, C 2 H 2 , CH 4 and the determination of the isotopic ratio 13 CO 2 / 12 CO 2 in combustion environment The second project consisted in mixing two near-IR fiber lasers in a non-linear crystal (PPLN) in order to produce a laser radiation by difference frequency generation in the middle-IR (3.15 - 3.43 μm), where the absorption bands of the molecules are the most intense. The first studies with this source were carried out on detection of ethylene (C 2 H 4 ) and benzene (C 6 H 6 ). Developments, characterizations and applications of these instruments in the near and middle IR are detailed and the advantages of the 2 spectral ranges is highlighted. (author)

  10. Synchronous photoelectrical observations of flare stars in the visible and near infrared ranges

    International Nuclear Information System (INIS)

    Bruevich, V.V.; Kilyachkov, N.N.; Shevchenko, V.S.; Burnashov, V.I.; Grinin, V.P.; Koryshev, V.V.; Shakhovskaya, N.I.

    1980-01-01

    The results of synchronous photoelectrical observations of the AD Leo and EV Lac flare stars made in 1975 in the Crimea in B-filter and in the near infrared region (i-band, lambdasub(ef) approximately 0.85 μm) and the observations of the UV Cet and EV Lac stars made in 1976 in the Astronomical Institute Uzbek SSR in three passbands: U, isub(TiO)(lambdasub(ef)=0.71 μ) and isub(C)(lambdasub(ef)=0.80μm) are given. Practically all strong flares in the visible spectral range were followed by the IR-flares. In about 70% of the cases the predicted infrared negative preflares were observed. The amplitudes (in erg/s) of the negative flares are comparable with the amplitude of the optical flares. The analysis of the observed data shows that: a) the amplitudes and the energies of the positive IR flares are in average the larger the stronger is the optical flare; b) the amplitudes of the negative IR preflares are on the contrary the smaller the stronger is the optical flare; c) there are infrared flares the main energy out of which takes place in the infrared range of wavelengths; d) The U-i color shows a positive correlation with the amplitude of the flare in U: the stronger is the flare the bluer is its radiation

  11. Near-IR period-luminosity relations for pulsating stars in ω Centauri (NGC 5139)

    Science.gov (United States)

    Navarrete, C.; Catelan, M.; Contreras Ramos, R.; Alonso-García, J.; Gran, F.; Dékány, I.; Minniti, D.

    2017-08-01

    Aims: The globular cluster ω Centauri (NGC 5139) hosts hundreds of pulsating variable stars of different types, thus representing a treasure trove for studies of their corresponding period-luminosity (PL) relations. Our goal in this study is to obtain the PL relations for RR Lyrae and SX Phoenicis stars in the field of the cluster, based on high-quality, well-sampled light curves in the near-infrared (IR). Methods: Observations were carried out using the VISTA InfraRed CAMera (VIRCAM) mounted on the Visible and Infrared Survey Telescope for Astronomy (VISTA). A total of 42 epochs in J and 100 epochs in KS were obtained, spanning 352 days. Point-spread function photometry was performed using DoPhot and DAOPHOT crowded-field photometry packages in the outer and inner regions of the cluster, respectively. Results: Based on the comprehensive catalog of near-IR light curves thus secured, PL relations were obtained for the different types of pulsators in the cluster, both in the J and KS bands. This includes the first PL relations in the near-IR for fundamental-mode SX Phoenicis stars. The near-IR magnitudes and periods of Type II Cepheids and RR Lyrae stars were used to derive an updated true distance modulus to the cluster, with a resulting value of (m - M)0 = 13.708 ± 0.035 ± 0.10 mag, where the error bars correspond to the adopted statistical and systematic errors, respectively. Adding the errors in quadrature, this is equivalent to a heliocentric distance of 5.52 ± 0.27 kpc. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile, with the VISTA telescope (project ID 087.D-0472, PI R. Angeloni).

  12. INFRARED COLOR-COLOR DIAGRAMS FOR AGB STARS

    Directory of Open Access Journals (Sweden)

    Kyung-Won Suh

    2007-09-01

    Full Text Available We present infrared color-color diagrams of AGB stars from the observations at near and mid infrared bands. We compile the observations for hundreds of OH/IR stars and carbon stars using the data from the Midcourse Space Experiment (MSX, the two micron sky survey (2MASS, and the IRAS point source catalog (PSC. We compare the observations with the theoretical evolutionary tracks of AGB stars. From the new observational data base and the theoretical evolution tracks, we discuss the meaning of the infrared color-color diagrams at different wavelengths.

  13. Infrared Counterparts to Chandra X-Ray Sources in the Antennae

    Science.gov (United States)

    Clark, D. M.; Eikenberry, S. S.; Brandl, B. R.; Wilson, J. C.; Carson, J. C.; Henderson, C. P.; Hayward, T. L.; Barry, D. J.; Ptak, A. F.; Colbert, E. J. M.

    2007-03-01

    We use deep J (1.25 μm) and Ks (2.15 μm) images of the Antennae (NGC 4038/4039) obtained with the Wide-field InfraRed Camera on the Palomar 200 inch (5 m) telescope, together with the Chandra X-ray source list of Zezas and coworkers to search for infrared counterparts to X-ray point sources. We establish an X-ray/IR astrometric frame tie with ~0.5" rms residuals over a ~4.3' field. We find 13 ``strong'' IR counterparts brighter than Ks=17.8 mag and 99.9% confidence level that IR counterparts to X-ray sources are ΔMKs~1.2 mag more luminous than average non-X-ray clusters. We also note that the X-ray/IR matches are concentrated in the spiral arms and ``overlap'' regions of the Antennae. This implies that these X-ray sources lie in the most ``super'' of the Antennae's super star clusters, and thus trace the recent massive star formation history here. Based on the NH inferred from the X-ray sources without IR counterparts, we determine that the absence of most of the ``missing'' IR counterparts is not due to extinction, but that these sources are intrinsically less luminous in the IR, implying that they trace a different (possibly older) stellar population. We find no clear correlation between X-ray luminosity classes and IR properties of the sources, although small-number statistics hamper this analysis.

  14. Ionization-induced solvent migration in acetanilide-methanol clusters inferred from isomer-selective infrared spectroscopy.

    Science.gov (United States)

    Weiler, Martin; Nakamura, Takashi; Sekiya, Hiroshi; Dopfer, Otto; Miyazaki, Mitsuhiko; Fujii, Masaaki

    2012-12-07

    We present the resonance-enhanced multiphoton ionization, infrared-ultraviolet hole burning (IR-UV HB), and IR dip spectra of the trans-acetanilide-methanol (AA-MeOH) cluster in the S(0), S(1), and cationic ground state (D(0)) in a supersonic jet. The IR-UV HB spectra demonstrate the co-existence of two isomers in S(0,1), in which MeOH binds either to the NH or the CO site of the peptide linkage in AA, denoted as AA(NH)-MeOH and AA(CO)-MeOH. When AA(CO)-MeOH is selectively ionized, its IR spectrum in D(0) is the same as that measured for AA(+) (NH)-MeOH. Thus, photoionization of AA(CO)-MeOH induces migration of MeOH from the CO to the NH site with 100% yield. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. SU-F-T-275: A Correlation Study On 3D Fluence-Based QA and 2D Dose Measurement-Based QA

    International Nuclear Information System (INIS)

    Liu, S; Mazur, T; Li, H; Green, O; Sun, B; Mutic, S; Yang, D

    2016-01-01

    Purpose: The aim of this paper was to demonstrate the feasibility and creditability of computing and verifying 3D fluencies to assure IMRT and VMAT treatment deliveries, by correlating the passing rates of the 3D fluence-based QA (P(ά)) to the passing rates of 2D dose measurementbased QA (P(Dm)). Methods: 3D volumetric primary fluencies are calculated by forward-projecting the beam apertures and modulated by beam MU values at all gantry angles. We first introduce simulated machine parameter errors (MU, MLC positions, jaw, gantry and collimator) to the plan. Using passing rates of voxel intensity differences (P(Ir)) and 3D gamma analysis (P(γ)), calculated 3D fluencies, calculated 3D delivered dose, and measured 2D planar dose in phantom from the original plan are then compared with those from corresponding plans with errors, respectively. The correlations of these three groups of resultant passing rates, i.e. 3D fluence-based QA (P(ά,Ir) and P(ά,γ)), calculated 3D dose (P(Dc,Ir) and P(Dc,γ)), and 2D dose measurement-based QA (P(Dm,Ir) and P(Dm,γ)), will be investigated. Results: 20 treatment plans with 5 different types of errors were tested. Spearman’s correlations were found between P(ά,Ir) and P(Dc,Ir), and also between P(ά,γ) and P(Dc,γ), with averaged p-value 0.037, 0.065, and averaged correlation coefficient ρ-value 0.942, 0.871 respectively. Using Matrixx QA for IMRT plans, Spearman’s correlations were also obtained between P(ά,Ir) and P(Dm,Ir) and also between P(ά,γ) and P(Dm,γ), with p-value being 0.048, 0.071 and ρ-value being 0.897, 0.779 respectively. Conclusion: The demonstrated correlations improve the creditability of using 3D fluence-based QA for assuring treatment deliveries for IMRT/VMAT plans. Together with advantages of high detection sensitivity and better visualization of machine parameter errors, this study further demonstrates the accuracy and feasibility of 3D fluence based-QA in pre-treatment QA and daily QA. Research

  16. Coherent control of D2/H2 dissociative ionization by a mid-infrared two-color laser field

    International Nuclear Information System (INIS)

    Wanie, Vincent; Ibrahim, Heide; Beaulieu, Samuel; Thiré, Nicolas; Schmidt, Bruno E; Légaré, François; Deng, Yunpei; Alnaser, Ali S; Litvinyuk, Igor V; Tong, Xiao-Min

    2016-01-01

    Steering the electrons during an ultrafast photo-induced process in a molecule influences the chemical behavior of the system, opening the door to the control of photochemical reactions and photobiological processes. Electrons can be efficiently localized using a strong laser field with a well-designed temporal shape of the electric component. Consequently, many experiments have been performed with laser sources in the near-infrared region (800 nm) in the interest of studying and enhancing the electron localization. However, due to its limited accessibility, the mid-infrared (MIR) range has barely been investigated, although it allows to efficiently control small molecules and even more complex systems. To push further the manipulation of basic chemical mechanisms, we used a MIR two-color (1800 and 900 nm) laser field to ionize H 2 and D 2 molecules and to steer the remaining electron during the photo-induced dissociation. The study of this prototype reaction led to the simultaneous control of four fragmentation channels. The results are well reproduced by a theoretical model solving the time-dependent Schrödinger equation for the molecular ion, identifying the involved dissociation mechanisms. By varying the relative phase between the two colors, asymmetries (i.e., electron localization selectivity) of up to 65% were obtained, corresponding to enhanced or equivalent levels of control compared to previous experiments. Experimentally easier to implement, the use of a two-color laser field leads to a better electron localization than carrier-envelope phase stabilized pulses and applying the technique in the MIR range reveals more dissociation channels than at 800 nm. (paper)

  17. ATR FT-IR spectroscopy on Vmh2 hydrophobin self-assembled layers for Teflon membrane bio-functionalization

    International Nuclear Information System (INIS)

    Portaccio, M.; Gravagnuolo, A.M.; Longobardi, S.; Giardina, P.; Rea, I.; De Stefano, L.; Cammarota, M.; Lepore, M.

    2015-01-01

    Graphical abstract: - Highlights: • Hydrophobin self-assembled layers on Teflon in different preparation conditions were investigated. • ATR collection data geometry allowed samples examination without any particular preparation. • Amide content, lipid/amide and carbohydrate/amide ratios of the protein layer were estimated. • Secondary structure of protein was determined for the examined samples. • FT-IR demonstrated to be of extreme relevance in monitoring hydrophobin self-assembled layers preparation. - Abstract: Surface functionalization by layers of hydrophobins, amphiphilic proteins produced by fungi offers a promising and green strategy for fabrication of biomedical and bioanalytical devices. The layering process of the Vmh2 hydrophobin from Pleurotus ostreatus on Teflon membrane has been investigated by Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) spectroscopy. In particular, protein layers obtained with hydrophobin purified with two different procedures and in various coating conditions have been examined. The layers have been characterized by quantifying the amide I and amide II band area together with the lipid/amide ratio and carbohydrate/amide ratio. This characterization can be very useful in evaluating the best purification strategy and coating conditions. Moreover the analysis of the secondary structure of the layered protein using the deconvolution procedure of amide I band indicate the prevalent contribution from β-sheet state. The results inferred by infrared spectroscopy have been also confirmed by scanning electron microscopy imaging

  18. ATR FT-IR spectroscopy on Vmh2 hydrophobin self-assembled layers for Teflon membrane bio-functionalization

    Energy Technology Data Exchange (ETDEWEB)

    Portaccio, M., E-mail: marianna.portaccio@unina2.it [Dipartimento di Medicina Sperimentale – Seconda Università di Napoli, Via S.M. di Costantinopoli, 16-80134 Napoli (Italy); Gravagnuolo, A.M., E-mail: alfredomaria.gravagnuolo@unina.it [Dipartimento di Scienze Chimiche, Università “Federico II”, Via Cintia, 21- 80126 Napoli (Italy); Longobardi, S., E-mail: sara.longobardi@unina.it [Dipartimento di Scienze Chimiche, Università “Federico II”, Via Cintia, 21- 80126 Napoli (Italy); Giardina, P., E-mail: paola.giardina@unina.it [Dipartimento di Scienze Chimiche, Università “Federico II”, Via Cintia, 21- 80126 Napoli (Italy); Rea, I., E-mail: ilaria.rea@na.imm.cnr.it [Institute for Microelectronics and Microsystems, CNR, Via P. Castellino, 111-80131 Napoli (Italy); De Stefano, L., E-mail: luca.destefano@na.imm.cnr.it [Institute for Microelectronics and Microsystems, CNR, Via P. Castellino, 111-80131 Napoli (Italy); Cammarota, M., E-mail: marcella.cammarota@unina2.it [Dipartimento di Medicina Sperimentale – Seconda Università di Napoli, Via S.M. di Costantinopoli, 16-80134 Napoli (Italy); Lepore, M., E-mail: maria.lepore@unina2.it [Dipartimento di Medicina Sperimentale – Seconda Università di Napoli, Via S.M. di Costantinopoli, 16-80134 Napoli (Italy)

    2015-10-01

    Graphical abstract: - Highlights: • Hydrophobin self-assembled layers on Teflon in different preparation conditions were investigated. • ATR collection data geometry allowed samples examination without any particular preparation. • Amide content, lipid/amide and carbohydrate/amide ratios of the protein layer were estimated. • Secondary structure of protein was determined for the examined samples. • FT-IR demonstrated to be of extreme relevance in monitoring hydrophobin self-assembled layers preparation. - Abstract: Surface functionalization by layers of hydrophobins, amphiphilic proteins produced by fungi offers a promising and green strategy for fabrication of biomedical and bioanalytical devices. The layering process of the Vmh2 hydrophobin from Pleurotus ostreatus on Teflon membrane has been investigated by Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) spectroscopy. In particular, protein layers obtained with hydrophobin purified with two different procedures and in various coating conditions have been examined. The layers have been characterized by quantifying the amide I and amide II band area together with the lipid/amide ratio and carbohydrate/amide ratio. This characterization can be very useful in evaluating the best purification strategy and coating conditions. Moreover the analysis of the secondary structure of the layered protein using the deconvolution procedure of amide I band indicate the prevalent contribution from β-sheet state. The results inferred by infrared spectroscopy have been also confirmed by scanning electron microscopy imaging.

  19. Heat transfer and energy efficiency in infrared paper dryers

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Magnus

    1999-11-01

    Infrared (IR) dryers are widely used in the paper industry, mainly in the production of coated paper grades. The thesis deals with various aspects of heat transfer and energy use in infrared heaters and dryers as employed in the paper industry. Both gas-fired and electric IR dryers are considered and compared. The thesis also provides an introduction to infrared heaters and infrared drying, including a review of recent literature in the field. The transport of thermal radiation inside a paper sheet was investigated and different IR dryers were compared in terms of their ability to transfer energy to the internal parts of a paper sheet. Although there were evident differences in the absorption of radiation between gas-fired and electric IR dryers, the distinction was found not to be as important as has generally been believed. The main differences appeared to be due to the choice of a one- or a two-sided dryer solution, rather than the spectral distributions emitted by the dryers. A method for evaluating the radiation efficiency of IR heaters was proposed. An electric IR heater was evaluated in the laboratory. The radiation efficiency of the heater was shown to be strongly dependent on the power level. The maximum efficiency, found at high power level, was close to 60 %. A procedure for evaluation of the total energy transfer efficiency of an infrared paper dryer was proposed and used in the evaluation of an electric IR dryer operating in an industrial coating machine. The efficiency of the dryer was roughly 40 %. A model for an electric IR heater was developed. The model includes non-grey radiative heat transfer between the different parts of the heater, as well as conduction in reflector material and convective cooling of the surfaces. Using IR module voltage as the only input, model predictions of temperatures and heat flux were found to agree well with experimental data both at steady state and under transient conditions. The model was also extended to include

  20. Improved signal to noise ratio and sensitivity of an infrared imaging video bolometer on large helical device by using an infrared periscope

    International Nuclear Information System (INIS)

    Pandya, Shwetang N.; Sano, Ryuichi; Peterson, Byron J.; Mukai, Kiyofumi; Enokuchi, Akito; Takeyama, Norihide

    2014-01-01

    An Infrared imaging Video Bolometer (IRVB) diagnostic is currently being used in the Large Helical Device (LHD) for studying the localization of radiation structures near the magnetic island and helical divertor X-points during plasma detachment and for 3D tomography. This research demands high signal to noise ratio (SNR) and sensitivity to improve the temporal resolution for studying the evolution of radiation structures during plasma detachment and a wide IRVB field of view (FoV) for tomography. Introduction of an infrared periscope allows achievement of a higher SNR and higher sensitivity, which in turn, permits a twofold improvement in the temporal resolution of the diagnostic. Higher SNR along with wide FoV is achieved simultaneously by reducing the separation of the IRVB detector (metal foil) from the bolometer's aperture and the LHD plasma. Altering the distances to meet the aforesaid requirements results in an increased separation between the foil and the IR camera. This leads to a degradation of the diagnostic performance in terms of its sensitivity by 1.5-fold. Using an infrared periscope to image the IRVB foil results in a 7.5-fold increase in the number of IR camera pixels imaging the foil. This improves the IRVB sensitivity which depends on the square root of the number of IR camera pixels being averaged per bolometer channel. Despite the slower f-number (f/# = 1.35) and reduced transmission (τ 0 = 89%, due to an increased number of lens elements) for the periscope, the diagnostic with an infrared periscope operational on LHD has improved in terms of sensitivity and SNR by a factor of 1.4 and 4.5, respectively, as compared to the original diagnostic without a periscope (i.e., IRVB foil being directly imaged by the IR camera through conventional optics). The bolometer's field of view has also increased by two times. The paper discusses these improvements in apt details

  1. FAR-INFRARED OBSERVATIONS OF THE VERY LOW LUMINOSITY EMBEDDED SOURCE L1521F-IRS IN THE TAURUS STAR-FORMING REGION

    International Nuclear Information System (INIS)

    Terebey, Susan; Fich, Michel; Noriega-Crespo, Alberto; Padgett, Deborah L.; Brooke, Tim; Carey, Sean; McCabe, Caer-Eve; Rebull, Luisa; Fukagawa, Misato; Audard, Marc; Evans, Neal J.; Guedel, Manuel; Hines, Dean; Huard, Tracy; Knapp, Gillian R.; Menard, Francois; Monin, Jean-Louis

    2009-01-01

    We investigate the environment of the very low luminosity object L1521F-IRS using data from the Taurus Spitzer Legacy Survey. The MIPS 160 μm image shows both extended emission from the Taurus cloud and emission from multiple cold cores over a 1 0 x 2 0 region. Analysis shows that the cloud dust temperature is 14.2 ± 0.4 K and the extinction ratio is A 160 /A K = 0.010 ± 0.001 up to A V ∼ 4 mag. We find κ 160 = 0.23 ± 0.046 cm 2 g -1 for the specific opacity of the gas-dust mixture. Therefore, for dust in the Taurus cloud we find that the 160 μm opacity is significantly higher than that measured for the diffuse interstellar medium, but not too different from dense cores, even at modest extinction values. Furthermore, the 160 μm image shows features that do not appear in the IRAS 100 μm image. We identify six regions as cold cores, i.e., colder than 14.2 K, all of which have counterparts in extinction maps or C 18 O maps. Three of the six cores contain embedded young stellar objects, which demonstrates the cores are sites of current star formation. We compare the effects of L1521F-IRS on its natal core and find there is no evidence for dust heating at 160 or 100 μm by the embedded source. From the infrared luminosity L TIR = 0.024 L sun we find L bol-int =0.034-0.046 L odot , thus confirming the source's low luminosity. Comparison of L1521F-IRS with theoretical simulations for the very early phases of star formation appears to rule out the first core collapse phase. The evolutionary state appears similar to or younger than the class 0 phase, and the estimated mass is likely to be substellar.

  2. How dead are dead galaxies? Mid-infrared fluxes of quiescent galaxies at redshift 0.3 < z < 2.5: implications for star formation rates and dust heating

    International Nuclear Information System (INIS)

    Fumagalli, Mattia; Labbé, Ivo; Patel, Shannon G.; Franx, Marijn; Van Dokkum, Pieter; Momcheva, Ivelina; Nelson, Erica; Brammer, Gabriel; Da Cunha, Elisabete; Rix, Hans-Walter; Maseda, Michael; Schreiber, Natascha M. Förster; Kriek, Mariska; Quadri, Ryan; Wake, David; Lundgren, Britt; Whitaker, Katherine E.; Marchesini, Danilo; Pacifici, Camilla; Skelton, Rosalind E.

    2014-01-01

    We investigate star formation rates (SFRs) of quiescent galaxies at high redshift (0.3 < z < 2.5) using 3D-HST WFC3 grism spectroscopy and Spitzer mid-infrared data. We select quiescent galaxies on the basis of the widely used UVJ color-color criteria. Spectral energy distribution (SED) fitting (rest-frame optical and near-IR) indicates very low SFRs for quiescent galaxies (sSFR ∼ 10 –12 yr –1 ). However, SED fitting can miss star formation if it is hidden behind high dust obscuration and ionizing radiation is re-emitted in the mid-infrared. It is therefore fundamental to measure the dust-obscured SFRs with a mid-IR indicator. We stack the MIPS 24 μm images of quiescent objects in five redshift bins centered on z = 0.5, 0.9, 1.2, 1.7, 2.2 and perform aperture photometry. Including direct 24 μm detections, we find sSFR ∼ 10 –11.9 × (1 + z) 4 yr –1 . These values are higher than those indicated by SED fitting, but at each redshift they are 20-40 times lower than those of typical star-forming galaxies. The true SFRs of quiescent galaxies might be even lower, as we show that the mid-IR fluxes can be due to processes unrelated to ongoing star formation, such as cirrus dust heated by old stellar populations and circumstellar dust. Our measurements show that star formation quenching is very efficient at every redshift. The measured SFR values are at z > 1.5 marginally consistent with the ones expected from gas recycling (assuming that mass loss from evolved stars refuels star formation) and well below that at lower redshifts.

  3. How dead are dead galaxies? Mid-infrared fluxes of quiescent galaxies at redshift 0.3 < z < 2.5: implications for star formation rates and dust heating

    Energy Technology Data Exchange (ETDEWEB)

    Fumagalli, Mattia; Labbé, Ivo; Patel, Shannon G.; Franx, Marijn [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Van Dokkum, Pieter; Momcheva, Ivelina; Nelson, Erica [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Brammer, Gabriel [European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Vitacura, Santiago (Chile); Da Cunha, Elisabete; Rix, Hans-Walter; Maseda, Michael [Max Planck Institute for Astronomy (MPIA), Konigstuhl 17, D-69117 Heidelberg (Germany); Schreiber, Natascha M. Förster [Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Kriek, Mariska [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Quadri, Ryan [Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States); Wake, David; Lundgren, Britt [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); Whitaker, Katherine E. [Astrophysics Science Division, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States); Marchesini, Danilo [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Pacifici, Camilla [Yonsei University Observatory, Yonsei University, Seoul 120-749 (Korea, Republic of); Skelton, Rosalind E. [South African Astronomical Observatory, Observatory Road, Cape Town (South Africa)

    2014-11-20

    We investigate star formation rates (SFRs) of quiescent galaxies at high redshift (0.3 < z < 2.5) using 3D-HST WFC3 grism spectroscopy and Spitzer mid-infrared data. We select quiescent galaxies on the basis of the widely used UVJ color-color criteria. Spectral energy distribution (SED) fitting (rest-frame optical and near-IR) indicates very low SFRs for quiescent galaxies (sSFR ∼ 10{sup –12} yr{sup –1}). However, SED fitting can miss star formation if it is hidden behind high dust obscuration and ionizing radiation is re-emitted in the mid-infrared. It is therefore fundamental to measure the dust-obscured SFRs with a mid-IR indicator. We stack the MIPS 24 μm images of quiescent objects in five redshift bins centered on z = 0.5, 0.9, 1.2, 1.7, 2.2 and perform aperture photometry. Including direct 24 μm detections, we find sSFR ∼ 10{sup –11.9} × (1 + z){sup 4} yr{sup –1}. These values are higher than those indicated by SED fitting, but at each redshift they are 20-40 times lower than those of typical star-forming galaxies. The true SFRs of quiescent galaxies might be even lower, as we show that the mid-IR fluxes can be due to processes unrelated to ongoing star formation, such as cirrus dust heated by old stellar populations and circumstellar dust. Our measurements show that star formation quenching is very efficient at every redshift. The measured SFR values are at z > 1.5 marginally consistent with the ones expected from gas recycling (assuming that mass loss from evolved stars refuels star formation) and well below that at lower redshifts.

  4. Femtosecond few-cycle mid-infrared laser pulses

    DEFF Research Database (Denmark)

    Liu, Xing

    The few-cycle pulses of mid-infrared (mid-IR, wavelength 2-10 microns) have attracted increasing attention owing to their great potentials for high order harmonic generation, time-resolved spectroscopy, precision of cutting and biomedical science.In this thesis, mid-IR frequency conversion.......2 - 5.5 μm with only one fixed pump wavelength, a feature absent in Kerr media. Finally, we experimentally observe supercontinuum generation spanning 1.5 octaves, generated in a 10 mm long silicon-rich nitride waveguide pumped by 100 pJ femtosecond pulses from an erbium fiber laser. The waveguide has...

  5. Generating Efficient Femtosecond Mid-infrared Pulse by Single Near-infrared Pump Wavelength in Bulk Nonlinear Crystal Without Phase-matching

    DEFF Research Database (Denmark)

    Zhou, Binbin; Guo, Hairun; Bache, Morten

    2014-01-01

    We experimentally demonstrate efficient mid-infrared pulse generation by dispersive wave radiation in bulk lithium niobate crystal. Femtosecond mid-IR pulses centering from 2.8-2.92 μm are generated using the single pump wavelengths from 1.25-1.45 μm. © 2014 Optical Society of America...

  6. Hollow-core infrared fiber incorporating metal-wire metamaterial

    DEFF Research Database (Denmark)

    Yan, Min; Mortensen, Asger

    2009-01-01

    Infrared (IR) light is considered important for short-range wireless communication, thermal sensing, spectroscopy, material processing, medical surgery, astronomy etc. However, IR light is in general much harder to transport than optical light or microwave radiation. Existing hollow-core IR...

  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. Melting of a beta-Hairpin Peptide Using Isotope-Edited 2D IR Spectroscopy and Simulations

    NARCIS (Netherlands)

    Smith, Adam W.; Lessing, Joshua; Ganim, Ziad; Peng, Chunte Sam; Tokmakoff, Andrei; Roy, Santanu; Jansen, Thomas L. C.; Knoester, Jasper

    2010-01-01

    Isotope-edited two-dimensional infrared spectroscopy has been used! to characterize the conformational heterogeneity of the beta-hairpin peptide TrpZip2 (17.2) across its thermal unfolding transition Four isotopologues were synthesized to probe hydrogen bonding and solvent exposure of the beta-turn

  9. Melting of a beta-hairpin peptide using isotope-edited 2D IR spectroscopy and simulations.

    NARCIS (Netherlands)

    Smith, A.W.; Lessing, J.; Ganim, Z.; Peng, C.S.; Tokmakoff, A.; Roy, S.; Jansen, T.L.Th.A.; Knoester, J.

    2010-01-01

    Isotope-edited two-dimensional infrared spectroscopy has been used to characterize the conformational heterogeneity of the beta-hairpin peptide TrpZip2 (TZ2) across its thermal unfolding transition. Four isotopologues were synthesized to probe hydrogen bonding and solvent exposure of the beta-turn

  10. Comparative study of potentially J{sub eff} = 0 ground state iridium(V) in SrLaNiIrO{sub 6}, SrLaMgIrO{sub 6}, and SrLaZnIrO{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, Klaus K.; Agrestini, Stefano; Tjeng, Liu Hao [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Tanaka, Arata [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima (Japan); Jansen, Martin [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Max Planck Institute for Solid State Research, Stuttgart (Germany)

    2017-12-13

    A series of polycrystalline double perovskites SrLaBIrO{sub 6} (B = Ni, Mg, Zn) containing Ir{sup 5+} (5d{sup 4}) was synthesized by solid state reactions, and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P2{sub 1}/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO{sub 6} and SrLaZnIrO{sub 6}, and 0.4 eV for SrLaMgIrO{sub 6}. SrLaNiIrO{sub 6} is an antiferromagnet with a Neel temperature of 74 K (μ{sub eff} = 3.3 μ{sub B}, θ{sub W} = -90 K), whereas SrLaMgIrO{sub 6} and SrLaZnIrO{sub 6} are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vleck-type response originating from the Ir{sup 5+} (5d{sup 4}, J{sub eff} = 0) ions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Simultaneous measurement of thermal diffusivity and effective infrared absorption coefficient in IR semitransparent and semiconducting n-CdMgSe crystals using photothermal radiometry

    Energy Technology Data Exchange (ETDEWEB)

    Pawlak, M., E-mail: mpawlak@fizyka.umk.pl [Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziądzka 5/7, Toruń (Poland); Maliński, M. [Department of Electronics and Computer Science, Koszalin University of Technology, 2 Śniadeckich St., Koszalin 75-453 (Poland)

    2015-01-10

    Highlights: • The new method of determination of the effective infrared absorption coefficient is presented. • The method can be used for transparent samples for the excitation radiation. • The effect of aluminum foil on the PTR signal in a transmission configuration is discussed. - Abstract: In this paper we propose a new procedure of simultaneous estimation of the effective infrared optical absorption coefficient and the thermal diffusivity of solid state samples using the photothermal infrared radiometry method in the transmission configuration. The proposed procedure relies on the analysis of the frequency dependent signal obtained from the samples covered with thin aluminum foil. This method can be applied for both optically opaque and transparent samples. The proposed method is illustrated with the results of the thermal diffusivity and the effective IR absorption coefficient obtained for several Cd{sub 1−x}Mg{sub x}Se crystals.

  12. First report of vertically aligned (Sn,Ir)O2:F solid solution nanotubes: Highly efficient and robust oxygen evolution electrocatalysts for proton exchange membrane based water electrolysis

    Science.gov (United States)

    Ghadge, Shrinath Dattatray; Patel, Prasad P.; Datta, Moni K.; Velikokhatnyi, Oleg I.; Shanthi, Pavithra M.; Kumta, Prashant N.

    2018-07-01

    One dimensional (1D) vertically aligned nanotubes (VANTs) of (Sn0.8Ir0.2)O2:10F are synthesized for the first time by a sacrificial template assisted approach. The aim is to enhance the electrocatalytic activity of F doped (Sn,Ir)O2 solid solution electrocatalyst for oxygen evolution reaction (OER) in proton exchange membrane (PEM) based water electrolysis by generating (Sn0.8Ir0.2)O2:10F nanotubes (NTs). The 1D vertical channels and the high electrochemically active surface area (ECSA ∼38.46 m2g-1) provide for facile electron transport. This results in low surface charge transfer resistance (4.2 Ω cm2), low Tafel slope (58.8 mV dec-1) and excellent electrochemical OER performance with ∼2.3 and ∼2.6 fold higher electrocatalytic activity than 2D thin films of (Sn0.8Ir0.2)O2:10F and benchmark IrO2 electrocatalysts, respectively. Furthermore, (Sn0.8Ir0.2)O2:10F NTs exhibit excellent mass activity (21.67 A g-1), specific activity (0.0056 mAcm-2) and TOF (0.016 s-1), which is ∼2-2.6 fold higher than thin film electrocatalysts at an overpotential of 270 mV, with a total mass loading of 0.3 mg cm-2. In addition, (Sn0.8Ir0.2)O2:10F NTs demonstrate remarkable electrochemical durability - comparable to thin films of (Sn0.8Ir0.2)O2:10F and pure IrO2, operated under identical testing conditions in PEM water electrolysis. These results therefore indicate promise of (Sn0.8Ir0.2)O2:10F NTs as OER electrocatalysts for efficient and sustainable hydrogen production.

  13. IR spectral analysis for the diagnostics of crust earthquake precursors

    Directory of Open Access Journals (Sweden)

    R. M. Umarkhodgaev

    2012-11-01

    Full Text Available Some possible physical processes are analysed that cause, under the condition of additional ionisation in a pre-breakdown electric field, emissions in the infrared (IR interval. The atmospheric transparency region of the IR spectrum at wavelengths of 7–15 μm is taken into account. This transparency region corresponds to spectral lines of small atmospheric constituents like CH4, CO2, N2O, NO2, NO, and O3. The possible intensities of the IR emissions observable in laboratories and in nature are estimated. The acceleration process of the electrons in the pre-breakdown electrical field before its adhesion to the molecules is analyzed. For daytime conditions, modifications of the adsorption spectra of the scattered solar emissions are studied; for nighttime, variations of emission spectra may be used for the analysis.

  14. Band shape of IR-absorption of complex molecules and restricted rotational diffusion

    International Nuclear Information System (INIS)

    Ivanov, E.N.; Umidulaev, Sh.U.

    1989-01-01

    The development of the theory of band shape (and Breadth) IR-absorption of complex molecules (regarding the molecules inside motions) is considered. It is supposed that a molecule fragment being responsible for IR-absorption takes part in the restricted rotational diffusion (RRD) with respect to the frame, and the molecule itself in general makes rotational motion (RM). Both kinds of motions are discussed in accordance with the theory of group motions representations. On the basis of correlative functions calculations of dipole moment a simple expression for the IR-absorption band shape have been obtained, which in itself uses to be the super position of two Lorencians with the semibreadths 2D 1 and 2D 1 +ν 2 0 (ν 2 0 +1D R accordingly (here D 1 is the coefficient of RM, D 2 is the coefficient of RRD, ν 2 0 is the well known function of RRD-cone divergence angle) in case of symmetric rotary abrasive disc. Analysis of experimental band shape of IR-absorption on the basis of the expression obtained allows to get information of MR-molecule parameters in general and RRD. It is really possible to determine the RRD-cone divergency angle from experimental weights of Lorencians. In accordance with experimental semibreadths the coefficient of RM D 1 and the coefficient of RRD D 2 are obtained. In conclusion it is noted that D 1 →0 (in the expression for the band shape of IR-absorption obtained), one of the Lorencians turns to the δ-function and finally there is an expression which describes IR-absorption band shape of molecules in polymer-mats. (author)

  15. Plk1 phosphorylation of IRS2 prevents premature mitotic exit via AKT inactivation

    Science.gov (United States)

    Chen, Long; Li, Zhiguo; Ahmad, Nihal; Liu, Xiaoqi

    2016-01-01

    Insulin receptor substrate (IRS) proteins play important roles by acting as a platform in transducing signals from transmembrane receptors upon growth factor stimulation. Although tyrosine phosphorylation on IRS proteins plays critical roles in signal transduction, phosphorylation of IRS proteins on serine/threonine residues are believed to play various regulatory roles on IRS protein function. However, studies on serine/threonine phosphorylation of IRS proteins are very limited, especially for insulin receptor substrate 2 (IRS2), one member of the IRS protein family. In this study, we identify Polo-like kinase 1 (Plk1) as the responsible kinase for phosphorylation of IRS2 on two serine residues, Ser 556 and Ser 1098. Phosphorylation of IRS2 on these two serine residues by Plk1 prevents the activation of the PI3K pathway upon growth factor stimulation by inhibiting the binding between IRS2 and the PI3K pathway components and increasing IRS2 protein degradation. Of significance, we show that IRS2 phosphorylation is cell cycle regulated and that Plk1 phosphorylation of IRS2 prevents premature mitotic exit via AKT inactivation. PMID:25830382

  16. Shelf-life of infrared dry-roasted almonds

    Science.gov (United States)

    Infrared heating was recently used to develop a more efficient roasting technology than traditional hot air roasting. Therefore, in this study, we evaluated the shelf-life of almonds roasted with three different approaches, namely infrared [IR], sequential infrared and hot air [SIRHA], and regular h...

  17. Infrared spectra of 4HeH+, 4HeD+, 3HeH+, and 3HeD+

    International Nuclear Information System (INIS)

    Crofton, M.W.; Altman, R.S.; Haese, N.N.; Oka, T.

    1989-01-01

    Isotopic species of the HeH + molecular ion provide an excellent testing ground for studying isotopic dependence of vibration--rotation constants because of the small masses of He and H isotopes. We have observed infrared spectra of the hot band v=2 left-arrow 1 of HeH + and fundamental bands of isotopic species HeD + , 3 HeH + , and 3 HeD + , and obtained the Dunham coefficients Y kl , and the isotopically independent parameters U kl , Δ He kl , and Δ H kl

  18. Thulium pumped mid-infrared 0.9–9μm supercontinuum generation in concatenated fluoride and chalcogenide glass fibers

    DEFF Research Database (Denmark)

    Kubat, Irnis; Petersen, Christian Rosenberg; Møller, Uffe Visbech

    2014-01-01

    of ZBLAN spanning the 0.9–4.1μm SC at the −30dB level. The ZBLAN fiber SC is then coupled into 10cm of As2Se3 chalcogenide Microstructured Optical Fiber (MOF) designed to have a zero-dispersion wavelength (λZDW) significantly below the 4.1μm InfraRed (IR) edge of the ZBLAN fiber SC, here 3.55μm...

  19. 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.

  20. Single and Double Infrared Transitions in Rapid Vapor Deposited Parahydrogen Solids: Application to Sample Thickness Determination and Quantitative Infrared Absorption Spectroscopy

    National Research Council Canada - National Science Library

    Tam, Simon

    2001-01-01

    ...) solid from its infrared (IR) absorption spectrum. Millimeters-thick pH2 solids of exceptional optical clarity can be produced by the rapid vapor deposition method M.E. Fajardo and S. Tam, J. Chem. Phys. 108, 4237 (1998...

  1. 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.

  2. Thermal effects of CO2 capture by solid adsorbents: some approaches by IR image processing

    International Nuclear Information System (INIS)

    Benevides Ferreira, J.F.; Pradere, C.; Batsale, J.C.; Jolly, J.; Pavageau, B.; Le Bourdon, G.; Mascetti, J.; Servant, L.

    2013-01-01

    Thanks to infrared thermography, we have studied the mechanisms of CO 2 capture by solid adsorbents (CO 2 capture via gas adsorption on various types of porous substrates) to better understand the physico-chemical mechanisms that control CO 2 -surface interactions. In order to develop in the future an efficient process for post-combustion CO 2 capture, it is necessary to quantify the energy of adsorption of the gas on the adsorbent (exothermic process). The released heat (heat of adsorption) is a key parameter for the choice of materials and for the design of capture processes. Infrared thermography is used, at first approach, to detect the temperature fields on a thin-layer of adsorbent during CO 2 adsorption. An analytical heat transfer model was developed to evaluate the adsorption heat flux and to estimate, via an inverse technique, the heat of adsorption. The main originality of our method is to estimate heat losses directly from the heat generated during the adsorption process. Then, the estimated heat loss is taken for an a posteriori calculation of the adsorption heat flux. Finally, the heat of adsorption may be estimated. The interest in using infrared thermography is also its ability to quickly change the experimental setup, for example, to switch from the adsorbent thin-layer to the adsorbent bed configuration. We present the first results tempting to link the thin-layer data to the propagation speed of the thermal front in a milli-fluidics adsorption bed, also observed by IR thermography. (authors)

  3. Structural, magnetic, and electronic transport properties of pyrochlore iridate Pr2Ir2O7

    Science.gov (United States)

    Kumar, Harish; Chaurasia, Rachna; Kumari, Pratibha; Paramanik, A. K.

    2018-04-01

    We have studied the structural, magnetic, and electronic transport properties of pyrochlore iridate Pr2Ir2O7. Structural investigation has been done using x-ray powder diffraction and Rietveld analysis. Pr2Ir2O7 crystallize in cubic crystallographic phase with Fd-3m space group. Temperature dependent magnetization data does not show magnetic bifurcation down to 2 K. Electrical resistivity data of Pr2Ir2O7 exhibits metallic behavior throughout temperature range. Below 50 K, a small rise in resistivity data of Pr2Ir2O7 is observed down to 12 K.

  4. Dynamics of liquids, molecules, and proteins measured with ultrafast 2D IR vibrational echo chemical exchange spectroscopy.

    Science.gov (United States)

    Fayer, M D

    2009-01-01

    A wide variety of molecular systems undergo fast structural changes under thermal equilibrium conditions. Such transformations are involved in a vast array of chemical problems. Experimentally measuring equilibrium dynamics is a challenging problem that is at the forefront of chemical research. This review describes ultrafast 2D IR vibrational echo chemical exchange experiments and applies them to several types of molecular systems. The formation and dissociation of organic solute-solvent complexes are directly observed. The dissociation times of 13 complexes, ranging from 4 ps to 140 ps, are shown to obey a relationship that depends on the complex's formation enthalpy. The rate of rotational gauche-trans isomerization around a carbon-carbon single bond is determined for a substituted ethane at room temperature in a low viscosity solvent. The results are used to obtain an approximate isomerization rate for ethane. Finally, the time dependence of a well-defined single structural transformation of a protein is measured.

  5. A Robust 96.6-dB-SNDR 50-kHz-Bandwidth Switched-Capacitor Delta-Sigma Modulator for IR Imagers in Space Instrumentation.

    Science.gov (United States)

    Dei, Michele; Sutula, Stepan; Cisneros, Jose; Pun, Ernesto; Jansen, Richard Jan Engel; Terés, Lluís; Serra-Graells, Francisco

    2017-06-02

    Infrared imaging technology, used both to study deep-space bodies' radiation and environmental changes on Earth, experienced constant improvements in the last few years, pushing data converter designers to face new challenges in terms of speed, power consumption and robustness against extremely harsh operating conditions. This paper presents a 96.6-dB-SNDR (Signal-to-Noise-plus-Distortion Ratio) 50-kHz-bandwidth fourth-order single-bit switched-capacitor delta-sigma modulator for ADC operating at 1.8 V and consuming 7.9 mW fit for space instrumentation. The circuit features novel Class-AB single-stage switched variable-mirror amplifiers (SVMAs) enabling low-power operation, as well as low sensitivity to both process and temperature deviations for the whole modulator. The physical implementation resulted in a 1.8-mm 2 chip integrated in a standard 0.18-µm 1-poly-6-metal (1P6M) CMOS technology, and it reaches a 164.6-dB Schreier figure of merit from experimental SNDR measurements without making use of any clock bootstrapping,analogcalibration,nordigitalcompensationtechnique. Whencoupledtoa2048×2048 IR imager, the current design allows more than 50 frames per minute with a resolution of 16 effective number of bits (ENOB) while consuming less than 300 mW.

  6. Scalable cross-point resistive switching memory and mechanism through an understanding of H2O2/glucose sensing using an IrOx/Al2O3/W structure.

    Science.gov (United States)

    Chakrabarti, Somsubhra; Maikap, Siddheswar; Samanta, Subhranu; Jana, Surajit; Roy, Anisha; Qiu, Jian-Tai

    2017-10-04

    The resistive switching characteristics of a scalable IrO x /Al 2 O 3 /W cross-point structure and its mechanism for pH/H 2 O 2 sensing along with glucose detection have been investigated for the first time. Porous IrO x and Ir 3+ /Ir 4+ oxidation states are observed via high-resolution transmission electron microscope, field-emission scanning electron spectroscopy, and X-ray photo-electron spectroscopy. The 20 nm-thick IrO x devices in sidewall contact show consecutive long dc cycles at a low current compliance (CC) of 10 μA, multi-level operation with CC varying from 10 μA to 100 μA, and long program/erase endurance of >10 9 cycles with 100 ns pulse width. IrO x with a thickness of 2 nm in the IrO x /Al 2 O 3 /SiO 2 /p-Si structure has shown super-Nernstian pH sensitivity of 115 mV per pH, and detection of H 2 O 2 over the range of 1-100 nM is also achieved owing to the porous and reduction-oxidation (redox) characteristics of the IrO x membrane, whereas a pure Al 2 O 3 /SiO 2 membrane does not show H 2 O 2 sensing. A simulation based on Schottky, hopping, and Fowler-Nordheim tunneling conduction, and a redox reaction, is proposed. The experimental I-V curve matches very well with simulation. The resistive switching mechanism is owing to O 2- ion migration, and the redox reaction of Ir 3+ /Ir 4+ at the IrO x /Al 2 O 3 interface through H 2 O 2 sensing as well as Schottky barrier height modulation is responsible. Glucose at a low concentration of 10 pM is detected using a completely new process in the IrO x /Al 2 O 3 /W cross-point structure. Therefore, this cross-point memory shows a method for low cost, scalable, memory with low current, multi-level operation, which will be useful for future highly dense three-dimensional (3D) memory and as a bio-sensor for the future diagnosis of human diseases.

  7. Pigments which reflect infrared radiation from fire

    Science.gov (United States)

    Berdahl, Paul H.

    1998-01-01

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

  8. D2O clusters isolated in rare-gas solids: Dependence of infrared spectrum on concentration, deposition rate, heating temperature, and matrix material

    Science.gov (United States)

    Shimazaki, Yoichi; Arakawa, Ichiro; Yamakawa, Koichiro

    2018-04-01

    The infrared absorption spectra of D2O monomers and clusters isolated in rare-gas matrices were systematically reinvestigated under the control of the following factors: the D2O concentration, deposition rate, heating temperature, and rare-gas species. We clearly show that the cluster-size distribution is dependent on not only the D2O concentration but also the deposition rate of a sample; as the rate got higher, smaller clusters were preferentially formed. Under the heating procedures at different temperatures, the cluster-size growth was successfully observed. Since the monomer diffusion was not enough to balance the changes in the column densities of the clusters, the dimer diffusion was likely to contribute the cluster growth. The frequencies of the bonded-OD stretches of (D2O)k with k = 2-6 were almost linearly correlated with the square root of the critical temperature of the matrix material. Additional absorption peaks of (D2O)2 and (D2O)3 in a Xe matrix were assigned to the species trapped in tight accommodation sites.

  9. VizieR Online Data Catalog: FIR data of IR-bright dust-obscured galaxies (DOGs) (Toba+, 2017)

    Science.gov (United States)

    Toba, Y.; Nagao, T.; Wang, W.-H.; Matsuhara, H.; Akiyama, M.; Goto, T.; Koyama, Y.; Ohyama, Y.; Yamamura, I.

    2017-11-01

    We investigate the star-forming activity of a sample of infrared (IR)-bright dust-obscured galaxies (DOGs) that show an extreme red color in the optical and IR regime, (i-[22])AB>7.0. Combining an IR-bright DOG sample with the flux at 22μm>3.8mJy discovered by Toba & Nagao (2016ApJ...820...46T) with the IRAS faint source catalog version 2 and AKARI far-IR (FIR) all-sky survey bright source catalog version 2, we selected 109 DOGs with FIR data. For a subsample of seven IR-bright DOGs with spectroscopic redshifts (0.07DOGs and (2) the contribution of the active galactic nucleus to IR luminosity increases with IR luminosity. By comparing the stellar mass and SFR relation for our DOG sample and the literature, we found that most of the IR-bright DOGs lie significantly above the main sequence of star-forming galaxies at similar redshift, indicating that the majority of IRAS- or AKARI-detected IR-bright DOGs are starburst galaxies. (1 data file).

  10. Moving the Plasmon of LaB₆ from IR to Near-IR via Eu-Doping.

    Science.gov (United States)

    Mattox, Tracy M; Coffman, D Keith; Roh, Inwhan; Sims, Christopher; Urban, Jeffrey J

    2018-02-01

    Lanthanum hexaboride (LaB₆) has become a material of intense interest in recent years due to its low work function, thermal stability and intriguing optical properties. LaB₆ is also a semiconductor plasmonic material with the ability to support strong plasmon modes. Some of these modes uniquely stretch into the infrared, allowing the material to absorb around 1000 nm, which is of great interest to the window industry. It is well known that the plasmon of LaB₆ can be tuned by controlling particle size and shape. In this work, we explore the options available to further tune the optical properties by describing how metal vacancies and Eu doping concentrations are additional knobs for tuning the absorbance from the near-IR to far-IR in La 1-x Eu x B₆ (x = 0, 0.2, 0.5, 0.8, and 1.0). We also report that there is a direct correlation between Eu concentration and metal vacancies within the Eu 1-x La x B₆.

  11. Covering that selectively absorbs visible and infrared radiation, and method for the production thereof

    OpenAIRE

    Céspedes, Eva; Prieto, C.; Escobar Galindo, R.; Sánchez-García, J. A.

    2011-01-01

    [EN] The present invention relates to a covering that selectively absorbs visible and infrared radiation, which comprises: (a) a first anti-diffusion barrier layer (2); (b) an IR-reflecting metallic layer (3) made from at least one metallic element selected from a group comprising Au, Ag, Al, Cu, Ti and Pt; (c) at least a second anti-diffusion barrier layer (4) formed by oxidation of the layer (3); (d) a structure that absorbs in the UV-VIS range, which comprises at least a first film (5) and...

  12. FT-IR, FT-Raman, NMR studies and ab initio-HF, DFT-B3LYP vibrational analysis of 4-chloro-2-fluoroaniline.

    Science.gov (United States)

    Arivazhagan, M; Anitha Rexalin, D

    2012-10-01

    The Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectra of 4-chloro-2-fluoroaniline (CFA) have been recorded and analyzed. The equilibrium geometry, bonding features and harmonic vibrational frequencies have been investigated with the help of ab initio and density functional theory (DFT) methods. The assignments of the vibrational spectra have been carried out with the help of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule are calculated by the Gauge including atomic orbital (GIAO) method. The first order hyperpolarizability (β(0)) of this novel molecular system and related properties (β, α(0) and Δα) of CFA are calculated using B3LYP/6-311++G(d,p) and HF/6-311++G(d,p) methods on the finite-field approach. The calculated results also show that the CFA molecule might have microscopic nonlinear optical (NLO) behavior with non-zero values. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The result confirms the occurrence of intramolecular charge transfer (ICT) within the molecule. The HOMO-LUMO energies UV-vis spectral analysis and MEP are performed by B3LYP/6-311++G(d,p) approach. A detailed interpretation of the infrared and Raman spectra of CFA is also reported based on total energy distribution (TED). The difference between the observed and scaled wave number values of the most of the fundamentals is very small. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Spectral filter for splitting a beam with electromagnetic radiation having wavelengths in the extreme ultraviolet (EUV) or soft X-Ray (Soft X) and the infrared (IR) wavelength range

    NARCIS (Netherlands)

    van Goor, F.A.; Bijkerk, Frederik; van den Boogaard, Toine; van den Boogaard, A.J.R.; van der Meer, R.

    2012-01-01

    Spectral filter for splitting the primary radiation from a generated beam with primary electromagnetic radiation having a wavelength in the extreme ultraviolet (EUV radiation) or soft X-ray (soft X) wavelength range and parasitic radiation having a wavelength in the infrared wavelength range (IR

  14. A Prospective Cohort Study on IRS Gene Polymorphisms in Type 2 ...

    African Journals Online (AJOL)

    Insulin resistance status was determined using the homeostatic model assessment for insulin resistance (HOMA-IR) index. Results: IRS1 polymorphisms were associated with increased insulin resistance (X2 = 5.09, p = 0.023) in T2DM patients with severe/acute hyperglycemia. IRS2 polymorphisms were not associated with ...

  15. The Reipurth 50 - north infrared source

    International Nuclear Information System (INIS)

    Casali, M.M.

    1991-01-01

    Near-infrared imaging, imaging polarimetry and CVF spectroscopy of Re50N reveal the presence of a single illuminating source, IRS1. The extinction around IRS1 seems to be distributed anisotropically, with a lower extinction path to the reflection nebula than in the line-of-sight. IRS1 appears to be a young steep-spectrum object, with the bulk of its IR emission coming from hot dust. Multiple scattering in the tail of the reflection nebula could explain its relatively blue colours away from IRS1. (author)

  16. Pixelated coatings and advanced IR coatings

    Science.gov (United States)

    Pradal, Fabien; Portier, Benjamin; Oussalah, Meihdi; Leplan, Hervé

    2017-09-01

    Reosc developed pixelated infrared coatings on detector. Reosc manufactured thick pixelated multilayer stacks on IR-focal plane arrays for bi-spectral imaging systems, demonstrating high filter performance, low crosstalk, and no deterioration of the device sensitivities. More recently, a 5-pixel filter matrix was designed and fabricated. Recent developments in pixelated coatings, shows that high performance infrared filters can be coated directly on detector for multispectral imaging. Next generation space instrument can benefit from this technology to reduce their weight and consumptions.

  17. Results with the UKIRT infrared camera

    International Nuclear Information System (INIS)

    Mclean, I.S.

    1987-01-01

    Recent advances in focal plane array technology have made an immense impact on infrared astronomy. Results from the commissioning of the first infrared camera on UKIRT (the world's largest IR telescope) are presented. The camera, called IRCAM 1, employs the 62 x 58 InSb DRO array from SBRC in an otherwise general purpose system which is briefly described. Several imaging modes are possible including staring, chopping and a high-speed snapshot mode. Results to be presented include the first true high resolution images at IR wavelengths of the entire Orion nebula

  18. Structural and magnetic properties of Sr{sub 2}Y{sub 1+x}Ir{sub 1-x}O{sub 6} materials

    Energy Technology Data Exchange (ETDEWEB)

    Aslan Cansever, Gizem; Geyer, Maximilian; Blum, Christian G.F.; Gass, Sebastian; Corredor, Laura T.; Maljuk, Andrey; Wolter, A.U.B. [Leibniz Institute for Solid State and Materials Research Dresden, IFW Dresden (Germany); Manna, Kaustuv [Max-Planck-Institute for Chemical Physics of Solids, Dresden (Germany); Hammerath, Franziska; Wurmehl, Sabine; Buechner, Bernd [Leibniz Institute for Solid State and Materials Research Dresden, IFW Dresden (Germany); Institute for Solid State Physics, TU Dresden (Germany)

    2016-07-01

    Ir-based materials have attracted a lot of attention because of the competition between the spin-orbit coupling, Coulomb interaction and crystal field. Sr{sub 2}YIrO{sub 6} double perovskites with Ir{sup +5} (5d{sup 4}) ions are generally considered to have a nonmagnetic ground state (J=0). However, Sr{sub 2}YIrO{sub 6} double perovskites have been reported to exhibit long-range magnetic order at low temperature and the distorted IrO{sub 6} octahedra were discussed to cause the magnetism in this compound [2]. In this study Sr{sub 2}Y{sub 1+x}Ir{sub 1-x}O{sub 6} materials were investigated in relation to structural and magnetic properties with varying Y and Ir concentrations. The samples were prepared by solid-state chemical reaction method. Magnetic susceptibility measurements were performed down to 0.4 K.

  19. Calculation of the structure and IR spectrum of methyl-b-D-glucopyranoside by density functional theory

    International Nuclear Information System (INIS)

    Babkov, L.M.; Korolevich, M.V.; Moisejkina, E.A.

    2010-01-01

    Structural-dynamic models of methyl-b-D-glucopyranoside have been constructed by a density functional method using a B3LYP functional in bases 6-31G(d) and 6-31+G(d,p). Energies have been minimized. Structures, dipole moments, polarizabilities, frequencies of normal modes in the harmonic approximation, and the intensity distribution in the molecular IR spectrum have been calculated. The calculation results have been compared with both the experimental spectra of methyl-b-D-glucopyranoside in the region 400-3700 cm -1 and data obtained within the framework of an approach that uses the classical valence-force method to calculate normal mode frequencies and the quantum-chemical CNDO/2 technique to calculate the electronic structure. (authors)

  20. Optical and Acoustic Sensor-Based 3D Ball Motion Estimation for Ball Sport Simulators †

    Directory of Open Access Journals (Sweden)

    Sang-Woo Seo

    2018-04-01

    Full Text Available Estimation of the motion of ball-shaped objects is essential for the operation of ball sport simulators. In this paper, we propose an estimation system for 3D ball motion, including speed and angle of projection, by using acoustic vector and infrared (IR scanning sensors. Our system is comprised of three steps to estimate a ball motion: sound-based ball firing detection, sound source localization, and IR scanning for motion analysis. First, an impulsive sound classification based on the mel-frequency cepstrum and feed-forward neural network is introduced to detect the ball launch sound. An impulsive sound source localization using a 2D microelectromechanical system (MEMS microphones and delay-and-sum beamforming is presented to estimate the firing position. The time and position of a ball in 3D space is determined from a high-speed infrared scanning method. Our experimental results demonstrate that the estimation of ball motion based on sound allows a wider activity area than similar camera-based methods. Thus, it can be practically applied to various simulations in sports such as soccer and baseball.

  1. INFRARED CLASSIFICATION AND LUMINOSITIES FOR DUSTY ACTIVE GALACTIC NUCLEI AND THE MOST LUMINOUS QUASARS

    International Nuclear Information System (INIS)

    Weedman, Daniel; Sargsyan, Lusine; Houck, James; Barry, Donald; Lebouteiller, Vianney

    2012-01-01

    Mid-infrared spectroscopic measurements from the Infrared Spectrometer (IRS) on Spitzer are given for 125 hard X-ray active galactic nuclei (AGNs; 14-195 keV) from the Swift Burst Alert Telescope (BAT) sample and for 32 AGNs with black hole masses (BHMs) from reverberation mapping. The 9.7 μm silicate feature in emission or absorption defines an infrared AGN classification describing whether AGNs are observed through dust clouds, indicating that 55% of the BAT AGNs are observed through dust. The mid-infrared dust continuum luminosity is shown to be an excellent indicator of intrinsic AGN luminosity, scaling closely with the hard X-ray luminosity, log νL ν (7.8 μm)/L(X) = –0.31 ± 0.35, and independent of classification determined from silicate emission or absorption. Dust luminosity scales closely with BHM, log νL ν (7.8 μm) = (37.2 ± 0.5) + 0.87 log BHM for luminosity in erg s –1 and BHM in M ☉ . The 100 most luminous type 1 quasars as measured in νL ν (7.8 μm) are found by comparing Sloan Digital Sky Survey (SDSS) optically discovered quasars with photometry at 22 μm from the Wide-Field Infrared Survey Explorer (WISE), scaled to rest frame 7.8 μm using an empirical template determined from IRS spectra. The most luminous SDSS/WISE quasars have the same maximum infrared luminosities for all 1.5 IR = 10 14.4 L ☉ . Comparing with dust-obscured galaxies from Spitzer and WISE surveys, we find no evidence of hyperluminous obscured quasars whose maximum infrared luminosities exceed the maximum infrared luminosities of optically discovered quasars. Bolometric luminosities L bol estimated from rest-frame optical or ultraviolet luminosities are compared to L IR . For the local AGN, the median log L IR /L bol = –0.35, consistent with a covering factor of 45% for the absorbing dust clouds. For the SDSS/WISE quasars, the median log L IR /L bol = 0.1, with extremes indicating that ultraviolet-derived L bol can be seriously underestimated even for type 1

  2. Study on IR Properties of Reduced Graphene Oxide

    Science.gov (United States)

    Ma, Deyue; Li, Xiaoxia; Guo, Yuxiang; Zeng, Yurun

    2018-01-01

    Firstly, the reduced graphene oxide was prepared by modified hummer method and characterized. Then, the complex refractive index of reduced graphene oxide in IR band was tested and its IR absorption and radiation properties were researched by correlated calculation. The results show that reduced graphene oxide prepared by hummer method are multilayered graphene with defects and functional groups on its surface. Its absorption in near and far IR bands is strong, but it’s weaker in middle IR band. At the IR atmosphere Window, its normal spectral emissivity decreases with wavelength increasing, and its total normal spectral emissivity in 3 ∼ 5μm and 8 ∼ 14μm are 0.75 and 0.625, respectively. Therefore, reduced graphene oxide can be used as IR absorption and coating materials and have a great potential in microwave and infrared compatible materials.

  3. 3D positioning scheme exploiting nano-scale IR-UWB orthogonal pulses.

    Science.gov (United States)

    Kim, Nammoon; Kim, Youngok

    2011-10-04

    In these days, the development of positioning technology for realizing ubiquitous environments has become one of the most important issues. The Global Positioning System (GPS) is a well-known positioning scheme, but it is not suitable for positioning in in-door/building environments because it is difficult to maintain line-of-sight condition between satellites and a GPS receiver. To such problem, various positioning methods such as RFID, WLAN, ZigBee, and Bluetooth have been developed for indoor positioning scheme. However, the majority of positioning schemes are focused on the two-dimension positioning even though three-dimension (3D) positioning information is more useful especially in indoor applications, such as smart space, U-health service, context aware service, etc. In this paper, a 3D positioning system based on mutually orthogonal nano-scale impulse radio ultra-wideband (IR-UWB) signals and cross array antenna is proposed. The proposed scheme uses nano-scale IR-UWB signals providing fine time resolution and high-resolution multiple signal specification algorithm for the time-of-arrival and the angle-of-arrival estimation. The performance is evaluated over various IEEE 802.15.4a channel models, and simulation results show the effectiveness of proposed scheme.

  4. MID-IR LUMINOSITIES AND UV/OPTICAL STAR FORMATION RATES AT z < 1.4

    International Nuclear Information System (INIS)

    Salim, Samir; Dickinson, Mark; Michael Rich, R.; Charlot, Stephane; Lee, Janice C.; Schiminovich, David; Perez-Gonzalez, Pablo G.; Ashby, Matthew L. N.; Noeske, Kai; Papovich, Casey; Weiner, Benjamin J.; Faber, S. M.; Ivison, Rob J.; Frayer, David T.; Walton, Josiah M.; Chary, Ranga-Ram; Bundy, Kevin; Koekemoer, Anton M.

    2009-01-01

    Ultraviolet (UV) nonionizing continuum and mid-infrared (IR) emission constitute the basis of two widely used star formation (SF) indicators at intermediate and high redshifts. We study 2430 galaxies with z 10 -10 12 L sun ). We show that the IR luminosity can be estimated from the UV and optical photometry to within a factor of 2, implying that most z IR >10 11 L sun , yet with little current SF. For them a reasonable amount of dust absorption of stellar light (but presumably higher than in nearby early-type galaxies) is sufficient to produce the observed levels of IR, which includes a large contribution from intermediate and old stellar populations. In our sample, which contains very few ultraluminous IR galaxies, optical and X-ray active galactic nuclei do not contribute on average more than ∼50% to the mid-IR luminosity, and we see no evidence for a large population of 'IR excess' galaxies.

  5. Įvairialyčiai lantano ir mangano oksido ir multiferoinio bismuto ferito heterodariniai

    Directory of Open Access Journals (Sweden)

    Bonifacas VENGALIS

    2011-11-01

    Full Text Available Pastaruoju metu naujų elektronikos prietaisų gamyboje buvo pasiekta didelė pažanga auginant, tyrinėjant ir pritaikant plonasluoksnes struktūras, sudarytas iš įvairių daugiakomponenčių funkcinių oksidų. Šiai oksidų grupei priklauso superlaidieji kupratai, mangano oksidai (manganitai, pasižymintys magnetovaržos reiškiniu, taip pat kiti feromagnetiniai, feroelektriniai, multiferoiniai oksidai. Manganitams (jų bendra formulė Ln1-xAxMnO3, kur Ln = La, Nd,..., o A - dvivalentis katijonas, toks kaip Ba, Sr ar Ca skiriama daug dėmesio dėl jų įdomių elektrinių savybių bei tinkamumo įvairiems spintronikos prietaisams kurti. Multiferoikai  (feroelektriniai feromagnetai pasižymi magnetoelektriniu efektu, duodančiu unikalią galimybę elektrinėms ir magnetinėms medžiagos savybėms valdyti panaudoti elektrinius ir magnetinius laukus. Bismuto feritas BiFeO3 (BFO, turintis romboedriškai deformuotą perovskito struktūrą, šiuo metu yra vienas labiausiai tyrinėjamų šios klasės junginių. Organiniai puslaidininkiai (OP taip pat atveria daug naujų galimybių elektronikai. Jų pranašumas yra didelė organinių junginių įvairovė ir palyginti paprasta ir pigi plonų sluoksnių gamybos technologija. Be to, OP pasižymi neįprastai didelėmis sukinių relaksacijos laiko vertėmis, todėl ateityje jie gali būti naudojami naujiems spintronikos prietaisams gaminti. Šiame straipsnyje apžvelgiami pastarųjų metų darbo autorių ir jų kolegų atlikti anksčiau minėtų medžiagų tyrimai. Daugiausia dėmesio skiriama magnetovaržinėmis savybėmis pasižyminčių lantano ir mangano oksidų (manganitų bei multiferoinio  BiFeO3 (BFO junginio plonųjų sluoksnių ir heterodarinių auginimui, tarpfazinių ribų tarp minėtų oksidų, laidžiojo SrTiO3 ir organinio puslaidininkio (Alq3 sudarymui, taip pat elektrinėms heterodarinių savybėms. Plonieji La2/3A1/3MnO3 (A = Ca, Sr, Ba, Ce sluoksniai, kurių storis d

  6. Evidence for coexisting magnetic order in frustrated three-dimensional honeycomb iridates Li2IrO3

    Science.gov (United States)

    Breznay, Nicholas; Ruiz, Alejandro; Frano, Alex; Analytis, James

    The search for unconventional magnetism has found a fertile hunting ground in 5d iridium oxide (iridate) materials. The competition between coulomb, spin-orbit, and crystal field energy scales in honeycomb iridates leads to a quantum magnetic system with localized spin-1/2 moments communicating through spin-anisotropic Kitaev exchange interactions. Although early and ongoing work has focused on layered two-dimensional honeycomb compounds such as Na2IrO3 and a 4d analog, RuCl3, recently discovered polytypes of Li2IrO3 take on three-dimensional honeycomb structures. Bulk thermodynamic studies, as well as recent resonant x-ray diffraction and absorption spectroscopy experiments, have uncovered a rich phase diagram for these three-dimensional honeycomb iridates. Low temperature incommensurate and commensurate magnetic orders can be stabilized by tuning the applied magnetic field, displaying a delicate coexistence that signals highly frustrated magnetism.

  7. Solute-solvent complex switching dynamics of chloroform between acetone and dimethylsulfoxide-two-dimensional IR chemical exchange spectroscopy.

    Science.gov (United States)

    Kwak, Kyungwon; Rosenfeld, Daniel E; Chung, Jean K; Fayer, Michael D

    2008-11-06

    Hydrogen bonds formed between C-H and various hydrogen bond acceptors play important roles in the structure of proteins and organic crystals, and the mechanisms of C-H bond cleavage reactions. Chloroform, a C-H hydrogen bond donor, can form weak hydrogen-bonded complexes with acetone and with dimethylsulfoxide (DMSO). When chloroform is dissolved in a mixed solvent consisting of acetone and DMSO, both types of hydrogen-bonded complexes exist. The two complexes, chloroform-acetone and chloroform-DMSO, are in equilibrium, and they rapidly interconvert by chloroform exchanging hydrogen bond acceptors. This fast hydrogen bond acceptor substitution reaction is probed using ultrafast two-dimensional infrared (2D-IR) vibrational echo chemical exchange spectroscopy. Deuterated chloroform is used in the experiments, and the 2D-IR spectrum of the C-D stretching mode is measured. The chemical exchange of the chloroform hydrogen bonding partners is tracked by observing the time-dependent growth of off-diagonal peaks in the 2D-IR spectra. The measured substitution rate is 1/30 ps for an acetone molecule to replace a DMSO molecule in a chloroform-DMSO complex and 1/45 ps for a DMSO molecule to replace an acetone molecule in a chloroform-acetone complex. Free chloroform exists in the mixed solvent, and it acts as a reactive intermediate in the substitution reaction, analogous to a SN1 type reaction. From the measured rates and the equilibrium concentrations of acetone and DMSO, the dissociation rates for the chloroform-DMSO and chloroform-acetone complexes are found to be 1/24 ps and 1/5.5 ps, respectively. The difference between the measured rate for the complete substitution reaction and the rate for complex dissociation corresponds to the diffusion limited rate. The estimated diffusion limited rate agrees well with the result from a Smoluchowski treatment of diffusive reactions.

  8. Ar ir CO2 plazma modifikuota aktyvintoji anglis acetono ir cikloheksano adsorbcijai

    Directory of Open Access Journals (Sweden)

    Piotr PIETROWSKI

    2012-06-01

    Full Text Available Žemos temperatūros plazmos poveikis, leidžiantis valdyti daugelio rūšių medžiagų, pvz., polimerų, metalų, anglies, paviršiaus savybes, šiuo metu yra tiriamas daugelyje mokslo sričių. Aktyvintoji  anglis (AC dėl savo fizikinių ir cheminių savybių naudojama kaip struktūrinis elementas dujų filtruose, kurie adsorbuodami daugelį skirtingų garų iš užteršto oro apsaugo kvėpavimo takus. Gerai žinoma, kad įvairios AC paviršiaus funkcinės grupės lemia jų hidrofobinę / hidrofilinę elgseną. Šame straipsnyje pristatomi pirminiai tyrimai, susiję su žemos temperatūros plazmos poveikiu komercinei aktyvintajai angliai. Aktyvintoji anglis buvo granuliuojama ir dedama į žemos temperatūros plazmos  rotacinę bandymų kamerą. Kamera buvo užpildoma atitinkamomis reaktyviosiomis dujomis. Plazmos poveikis buvo tiriamas nustatant aktyvintosios anglies paviršiaus dviejų pasirinktų rūšių organinių garų adsorbcijos izotermas, taip pat stebint šių garų adsorbcijos dinamiką ant dujų filtro, pagaminto iš plazma aktyvintos anglies. Remiantis gautais rezultatais, galima daryti išvadą, kad žemos temperatūros plazmos technologija gali būti taikoma aktyvintosios anglies savybėms pagerinti užtikrinant geresnę žemos temperatūros organinių garų adsorbciją.DOI: http://dx.doi.org/10.5755/j01.ms.18.2.1919

  9. Synthesis, Crystal and Electronic Structure of the Quaternary Magnetic EuTAl4Si2 (T = Rh and Ir) Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Maurya, Arvind [Tata Institute of Fundamental Research; Thamizhavel, Arumugam [Tata Institute of Fundamental Research; Provino, Alessia [University of Genova; Pani, Marcella [University of Genova; Manfrinetti, Pietro [University of Genova; Paudyal, Durga [Ames Laboratory; Dhar, Sudesh Kumar [Tata Institute of Fundamental Research

    2014-01-22

    Single crystals of the quaternary europium compounds EuRhAl4Si2 and EuIrAl4Si2 were synthesized by using the Al–Si binary eutectic as a flux. The structure of the two quaternary compounds has been refined by single crystal X-ray diffraction. Both compounds are stoichiometric and adopt an ordered derivative of the ternary KCu4S3 structure type (tetragonal tP8, P4/mmm). The two compounds reported here represent the first example of a quaternary and truly stoichiometric 1:1:4:2 phase crystallizing with this structure type. In light of our present results, the structure of the BaMg4Si3 compound given in literature as representing a new prototype is actually isotypic with the KCu4S3 structure. Local spin density approximation including the Hubbard U parameter (LSDA + U) calculations show that Eu ions are in the divalent state, with a significant hybridization between the Eu 5d, Rh (Ir) 4d (5d), Si 3p and Al 3p states. Magnetic susceptibility measured along the [001] direction confirms the divalent nature of the Eu ions in EuRhAl4Si2 and EuIrAl4Si2, which order magnetically near 11 and 15 K, respectively.

  10. Žieminių kviečių grūdų užterštumo mikromicetais ir mikotoksinais priklausomumas nuo tręšimo lygio

    OpenAIRE

    Mankevičienė, Audronė; Dabkevičius, Zenonas; Mačkinaitė, Rimutė; Cesevičienė, Jurgita

    2006-01-01

    Žieminių kviečių (Triticum aestivum L.) grūdų užsiteršimo mikroskopiniais grybais ir mikotoksinais tyrimai atlikti 2002-2004 m. Lietuvos žemdirbystės institute. Žieminiai kviečiai 'Ada' ir 'Zentos' tyrimų laikotarpiu buvo tręšiami 3 lygiais: netręšta (N0P0K0), vidutinis tręšimo lygis (N90P80K120S6), didžiausias tręšimo lygis (N180P80K140S13). Grūdų mikrobiologinės ir užterštumo mikotoksinais deoksinivalenoliu (DON), zearalenonu (ZEN) ir T-2 toksinu analizės atliktos tuoj po derliaus nuėmimo. ...

  11. TG/FT-IR characterization of additives typically employed in EPDM formulations

    Directory of Open Access Journals (Sweden)

    Natália Beck Sanches

    2015-06-01

    Full Text Available AbstractThermogravimetric analysis coupled to Fourier transform infrared spectroscopy (TG/FT-IR is a very popular technique for rubbers characterization. It involves analyses of the base polymer and additives. Ethylene–propylene–diene (EPDM rubbers are frequently investigated by TG/FT-IR; however, the focus has been the degradation temperature range of the polymer. In this study, unvulcanized and vulcanized EPDM rubber and its additives were investigated by TG/FT-IR, without solvent extraction, and in a wide temperature range. Initially, the additives were individually characterized. TG/FT-IR identified the characteristic groups of all the additives analyzed and distinguished them from each other. Afterwards, unvulcanized and vulcanized EPDM rubbers were investigated without prior extraction.TG/FT-IR detected absorptions due to the additives tetramethylthiuram monosulfide and 2-mercaptobenzothiazole. Both of these sulfur-containing additives were present in the EPDM formulation at concentrations of 0.7 phr (0.63 wt %. The TG/FT-IR technique had some limitations, because not all the additives in EPDM rubber were detected. Paraffin oil, stearic acid and 2,2,4-trimethyl-1,2-dihydroquinoline functional groups were not observed in either the unvulcanized or vulcanized EPDM. Nevertheless, in addition to the ability of this method to detect sulfur-containing groups, the lack of a pre-extraction reduces the time and effort required for additive analysis in rubbers.

  12. Fourier-transform infrared spectroscopic studies of dithia ...

    Indian Academy of Sciences (India)

    Unknown

    limited region 1000–1150 cm–1.10 Therefore, in the present paper we report and analyse Fourier-trans- form infrared (FT-IR) spectra of S2TPP and its chemically prepared cation. 2. Experimental. Dithia tetraphenyl porphyrine was received from. Professor A L Verma as a gift and used without fur- ther purification. However ...

  13. Honey bee odorant-binding protein 14: effects on thermal stability upon odorant binding revealed by FT-IR spectroscopy and CD measurements.

    Science.gov (United States)

    Schwaighofer, Andreas; Kotlowski, Caroline; Araman, Can; Chu, Nam; Mastrogiacomo, Rosa; Becker, Christian; Pelosi, Paolo; Knoll, Wolfgang; Larisika, Melanie; Nowak, Christoph

    2014-03-01

    In the present work, we study the effect of odorant binding on the thermal stability of honey bee (Apis mellifera L.) odorant-binding protein 14. Thermal denaturation of the protein in the absence and presence of different odorant molecules was monitored by Fourier transform infrared spectroscopy (FT-IR) and circular dichroism (CD). FT-IR spectra show characteristic bands for intermolecular aggregation through the formation of intermolecular β-sheets during the heating process. Transition temperatures in the FT-IR spectra were evaluated using moving-window 2D correlation maps and confirmed by CD measurements. The obtained results reveal an increase of the denaturation temperature of the protein when bound to an odorant molecule. We could also discriminate between high- and low-affinity odorants by determining transition temperatures, as demonstrated independently by the two applied methodologies. The increased thermal stability in the presence of ligands is attributed to a stabilizing effect of non-covalent interactions between odorant-binding protein 14 and the odorant molecule.

  14. Infrared spectra and tunneling dynamics of the N2-D2O and OC-D2O complexes in the v2 bend region of D2O.

    Science.gov (United States)

    Zhu, Yu; Zheng, Rui; Li, Song; Yang, Yu; Duan, Chuanxi

    2013-12-07

    The rovibrational spectra of the N2-D2O and OC-D2O complexes in the v2 bend region of D2O have been measured in a supersonic slit jet expansion using a rapid-scan tunable diode laser spectrometer. Both a-type and b-type transitions were observed for these two complexes. All transitions are doubled, due to the heavy water tunneling within the complexes. Assuming the tunneling splittings are the same in K(a) = 0 and K(a) = 1, the band origins, all three rotational and several distortion constants of each tunneling state were determined for N2-D2O in the ground and excited vibrational states, and for OC-D2O in the excited vibrational state, respectively. The averaged band origin of OC-D2O is blueshifted by 2.241 cm(-1) from that of the v2 band of the D2O monomer, compared with 1.247 cm(-1) for N2-D2O. The tunneling splitting of N2-D2O in the ground state is 0.16359(28) cm(-1), which is about five times that of OC-D2O. The tunneling splittings decrease by about 26% for N2-D2O and 23% for OC-D2O, respectively, upon excitation of the D2O bending vibration, indicating an increase of the tunneling barrier in the excited vibrational state. The tunneling splittings are found to have a strong dependence on intramolecular vibrational excitation as well as a weak dependence on quantum number K(a).

  15. Infrared analysis for determining macronutrients in human milk

    DEFF Research Database (Denmark)

    Michaelsen, K F; Pedersen, S B; Skafte, L

    1988-01-01

    Infrared (IR) analysis is widely used for routine analysis of cow milk in dairies. The aim of this study was to evaluate the precision and accuracy of an IR analyzer (Milko-scan 104) for measuring protein, fat, carbohydrate, and, indirectly, the energy content of human milk. The results of the IR...

  16. An Optical and Infrared Time-domain Study of the Supergiant Fast X-Ray Transient Candidate IC 10 X-2

    Science.gov (United States)

    Kwan, Stephanie; Lau, Ryan M.; Jencson, Jacob; Kasliwal, Mansi M.; Boyer, Martha L.; Ofek, Eran; Masci, Frank; Laher, Russ

    2018-03-01

    We present an optical and infrared (IR) study of IC 10 X-2, a high-mass X-ray binary in the galaxy IC 10. Previous optical and X-ray studies suggest that X-2 is a Supergiant Fast X-ray Transient: a large-amplitude (factor of ∼100), short-duration (hours to weeks) X-ray outburst on 2010 May 21. We analyze R- and g-band light curves of X-2 from the intermediate Palomar Transient Factory taken between 2013 July 15 and 2017 February 14 that show high-amplitude (≳1 mag), short-duration (≲8 days) flares and dips (≳0.5 mag). Near-IR spectroscopy of X-2 from Palomar/TripleSpec show He I, Paschen-γ, and Paschen-β emission lines with similar shapes and amplitudes as those of luminous blue variables (LBVs) and LBV candidates (LBVc). Mid-IR colors and magnitudes from Spitzer/Infrared Array Camera photometry of X-2 resemble those of known LBV/LBVcs. We suggest that the stellar companion in X-2 is an LBV/LBVc and discuss possible origins of the optical flares. Dips in the optical light curve are indicative of eclipses from optically thick clumps formed in the winds of the stellar counterpart. Given the constraints on the flare duration (0.02–0.8 days) and the time between flares (15.1 ± 7.8 days), we estimate the clump volume filling factor in the stellar winds, f V , to be 0.01interpret the origin of the optical flares as the accretion of clumps formed in the winds of an LBV/LBVc onto the compact object.

  17. Mass loss from OH/IR stars - Models for the infrared emission of circumstellar dust shells

    Science.gov (United States)

    Justtanont, K.; Tielens, A. G. G. M.

    1992-01-01

    The IR emission of a sample of 24 OH/IR stars is modeled, and the properties of circumstellar dust and mass-loss rate of the central star are derived. It is shown that for some sources the observations of the far-IR emission is well fitted with a lambda exp -1 law, while some have a steeper index of 1.5. For a few sources, the presence of circumstellar ice grains is inferred from detailed studies of the observed 10-micron feature. Dust mass-loss rates are determined from detailed studies for all the stars in this sample. They range from 6.0 x 10 exp -10 solar mass/yr for an optically visible Mira to 2.2 x 10 exp -6 solar mass/yr for a heavily obscured OH/IR star. These dust mass-loss rates are compared to those calculated from IRAS photometry using 12-, 25-, and 60-micron fluxes. The dust mass-loss rates are also compared to gas mass-loss rates determined from OH and CO observations. For stars with tenuous shells, a dust-to-gas ratio of 0.001 is obtained.

  18. Tunable optical coherence tomography in the infrared range using visible photons

    Science.gov (United States)

    Paterova, Anna V.; Yang, Hongzhi; An, Chengwu; Kalashnikov, Dmitry A.; Krivitsky, Leonid A.

    2018-04-01

    Optical coherence tomography (OCT) is an appealing technique for bio-imaging, medicine, and material analysis. For many applications, OCT in mid- and far-infrared (IR) leads to significantly more accurate results. Reported mid-IR OCT systems require light sources and photodetectors which operate in mid-IR range. These devices are expensive and need cryogenic cooling. Here, we report a proof-of-concept demonstration of a wavelength tunable IR OCT technique with detection of only visible range photons. Our method is based on the nonlinear interference of frequency correlated photon pairs. The nonlinear crystal, introduced in the Michelson-type interferometer, generates photon pairs with one photon in the visible and another in the IR range. The intensity of detected visible photons depends on the phase and loss of IR photons, which interact with the sample under study. This enables us to characterize sample properties and perform imaging in the IR range by detecting visible photons. The technique possesses broad wavelength tunability and yields a fair axial and lateral resolution, which can be tailored to the specific application. The work contributes to the development of versatile 3D imaging and material characterization systems working in a broad range of IR wavelengths, which do not require the use of IR-range light sources and photodetectors.

  19. Evaluation on the concentration change of paeoniflorin and glycyrrhizic acid in different formulations of Shaoyao-Gancao-Tang by the tri-level infrared macro-fingerprint spectroscopy and the whole analysis method

    Science.gov (United States)

    Liu, Aoxue; Wang, Jingjuan; Guo, Yizhen; Xiao, Yao; Wang, Yue; Sun, Suqin; Chen, Jianbo

    2018-03-01

    As a kind of common prescriptions, Shaoyao-Gancao-Tang (SGT) contains two Chinese herbs with four different proportions which have different clinical efficacy because of their various components. In order to investigate the herb-herb interaction mechanisms, we used the method of tri-level infrared macro-fingerprint spectroscopy to evaluate the concentration change of active components of four SGTs in this research. Fourier transform infrared spectroscopy (FT-IR) and Second derivative infrared spectroscopy (SD-IR) can recognize the multiple prescriptions directly and simultaneously. 2D-IR spectra enhance the spectral resolution and obtain much new information for discriminating the similar complicated samples of SGT. Furthermore, the whole analysis method from the analysis of the main components to the specific components and the relative content of the components may evaluate the quality of TCM better. Then we concluded that paeoniflorin and glycyrrhizic acid were the highest proportion in active ingredients in SGT-12:1 and the lowest one in SGT-12:12, which matched the HPLC-DAD results. It is demonstrated that the method composed by the tri-level infrared macro-fingerprint spectroscopy and the whole analysis can be applicable for effective, visual and accurate analysis and identification of very complicated and similar mixture systems of traditional Chinese medicine.

  20. Infrared thermography of solid surfaces in a fire

    International Nuclear Information System (INIS)

    Meléndez, J; Foronda, A; Aranda, J M; López, F; López del Cerro, F J

    2010-01-01

    Fire resistance tests are commonplace in industry. The aerospace sector is particularly active in this area, since the behaviour of advanced materials, such as composites, when in a fire is not fully understood yet. Two of the main obstacles are the inherent difficulty of direct surface measurements in such a harsh environment (especially on the exposed side of the specimens) and the lack of spatial resolution of the usual measuring devices, namely thermocouples (TCs). This paper presents a way to overcome these problems by using an infrared (IR) camera to study the exposed side of composite plates exposed to fire. A method for minimizing the effect of the flame (thus making it as 'transparent' as possible) was developed, resulting in 2D temperature maps of the plate surface. The assumptions that the method relies on were verified by data analysis and ad hoc emission–transmission experiments. The errors associated with two slightly different versions of the method were studied, and comparisons with TC measurements were performed. It was found that the IR method provides better results than TCs, not only due to its spatial resolution capability but also because of the non-intrusive nature of IR thermography, as opposed to the local effects caused by TCs, which became evident during the experiments

  1. The structural and optical constants of Ag2S semiconductor nanostructure in the Far-Infrared.

    Science.gov (United States)

    Zamiri, Reza; Abbastabar Ahangar, Hossein; Zakaria, Azmi; Zamiri, Golnoosh; Shabani, Mehdi; Singh, Budhendra; Ferreira, J M F

    2015-01-01

    In this paper a template-free precipitation method was used as an easy and low cost way to synthesize Ag2S semiconductor nanoparticles. The Kramers-Kronig method (K-K) and classical dispersion theory was applied to calculate the optical constants of the prepared samples, such as the reflective index n(ω) and dielectric constant ε(ω) in Far-infrared regime. Nanocrystalline Ag2S was synthesized by a wet chemical precipitation method. Ag2S nanoparticle was characterized by X-ray diffraction, Scanning Electron Microscopy, UV-visible, and FT-IR spectrometry. The refinement of the monoclinic β-Ag2S phase yielded a structure solution similar to the structure reported by Sadanaga and Sueno. The band gap of Ag2S nanoparticles is around 0.96 eV, which is in good agreement with previous reports for the band gap energy of Ag2S nanoparticles (0.9-1.1 eV). The crystallite size of the synthesized particles was obtained by Hall-Williamson plot for the synthesized Ag2S nanoparticles and it was found to be 217 nm. The Far-infrared optical constants of the prepared Ag2S semiconductor nanoparticles were evaluated by means of FTIR transmittance spectra data and K-K method. Graphical abstractThe Far-infrared optical constants of Ag2S semiconductor nanoparticles.

  2. Hyperfine interactions and electric dipole moments in the [16.0]1.5(v = 6), [16.0]3.5(v = 7), and X2Δ(5/2) states of iridium monosilicide, IrSi.

    Science.gov (United States)

    Le, Anh; Steimle, Timothy C; Morse, Michael D; Garcia, Maria A; Cheng, Lan; Stanton, John F

    2013-12-19

    The (6,0)[16.0]1.5-X(2)Δ(5/2) and (7,0)[16.0]3.5-X(2)Δ(5/2) bands of IrSi have been recorded using high-resolution laser-induced fluorescence spectroscopy. The field-free spectra of the (191)IrSi and (193)IrSi isotopologues were modeled to generate a set of fine, magnetic hyperfine, and nuclear quadrupole hyperfine parameters for the X(2)Δ(5/2)(v = 0), [16.0]1.5(v = 6), and [16.0]3.5 (v = 7) states. The observed optical Stark shifts for the (193)IrSi and (191)IrSi isotopologues were analyzed to produce the permanent electric dipole moments, μ(el), of -0.414(6) D and 0.782(6) D for the X(2)Δ(5/2) and [16.0]1.5 (v = 6) states, respectively. Properties of the X(2)Δ(5/2) state computed using relativistic coupled-cluster methods clearly indicate that electron correlation plays an essential role. Specifically, inclusion of correlation changes the sign of the dipole moment and is essential for achieving good accuracy for the nuclear quadrupole coupling parameter eQq0.

  3. A Novel Infrared Gas Monitor

    Science.gov (United States)

    Wang, Yingding; Zhong, Hongjie

    2000-03-01

    In the paper a novel non-dispersive infrared(IR) gas monitor is described.It is based on the principle that certain gases absorb IR radiation at specific(and often unique) wavelengths.Conventional devices typically include several primary components:a broadband source, usually an incandescent filament,a rotating chopper shutter,a narrow-band filter,a sample tube and a detector. We have developed a number of IR light emitting diodes(LED) having narrow optical bandwidths and which can be intensity modulated by electrical means,for example InAsSbP(4.2 micron)LED.The IR LED can thus replace the thermal source,narrow-band filter and chopper assembly of the conventional IR gas monitor,yielding a solid state,low- powered,compact and almost maintenance-free instrument with high sensitivity and stability and which free of the effects of mechanical vibration too. The detector used in the IR gas monitor is the solid-state detector,such as PbS,PbSe, InSb,HgCdTe,TGS,LT and PZT detector etc. The different configuration of the IR gas monitor is designed.For example,two-path version for measuring methane concentration by monitoring the 3.31 micron absorption band,it can eliminate the interference effects,such as to compensate for LED intensity changes caused by power and temperature variations,and for signal fluctuations due to changes in detector bias. we also have designed portable single-beam version without the sample tube.Its most primary advantage is very cheap(about cost USD 30 ).It measures carbon dioxide concentration by monitoring the 4.25 micron absorption band.Thought its precisions is low,it is used to control carbon dioxide concentration in the air in the green houses and plastic houses(there are about twenty millon one in the China).Because more carbon dioxide will increase the quanity of vegetable and flower production to a greatextent. It also is used in medical,sanitary and antiepidemic applications,such as hospital, store,hotel,cabin and ballroom etc. Key words:infrared

  4. Modifying infrared scattering effects of single yeast cells with plasmonic metal mesh

    Science.gov (United States)

    Malone, Marvin A.; Prakash, Suraj; Heer, Joseph M.; Corwin, Lloyd D.; Cilwa, Katherine E.; Coe, James V.

    2010-11-01

    The scattering effects in the infrared (IR) spectra of single, isolated bread yeast cells (Saccharomyces cerevisiae) on a ZnSe substrate and in metal microchannels have been probed by Fourier transform infrared imaging microspectroscopy. Absolute extinction [(3.4±0.6)×10-7 cm2 at 3178 cm-1], scattering, and absorption cross sections for a single yeast cell and a vibrational absorption spectrum have been determined by comparing it to the scattering properties of single, isolated, latex microspheres (polystyrene, 5.0 μm in diameter) on ZnSe, which are well modeled by the Mie scattering theory. Single yeast cells were then placed into the holes of the IR plasmonic mesh, i.e., metal films with arrays of subwavelength holes, yielding "scatter-free" IR absorption spectra, which have undistorted vibrational lineshapes and a rising generic IR absorption baseline. Absolute extinction, scattering, and absorption spectral profiles were determined for a single, ellipsoidal yeast cell to characterize the interplay of these effects.

  5. An IR investigation of solid amorphous ethanol - Spectra, properties, and phase changes

    Science.gov (United States)

    Hudson, Reggie L.

    2017-12-01

    Mid- and far-infrared spectra of condensed ethanol (CH3CH2OH) at 10-160 K are presented, with a special focus on amorphous ethanol, the form of greatest astrochemical interest, and with special attention given to changes at 155-160 K. Infrared spectra of amorphous and crystalline forms are shown. The refractive index at 670 nm of amorphous ethanol at 16 K is reported, along with three IR band strengths and a density. A comparison is made to recent work on the isoelectronic compound ethanethiol (CH3CH2SH), and several astrochemical applications are suggested for future study.

  6. Biological effects and medical applications of infrared radiation.

    Science.gov (United States)

    Tsai, Shang-Ru; Hamblin, Michael R

    2017-05-01

    Infrared (IR) radiation is electromagnetic radiation with wavelengths between 760nm and 100,000nm. Low-level light therapy (LLLT) or photobiomodulation (PBM) therapy generally employs light at red and near-infrared wavelengths (600-100nm) to modulate biological activity. Many factors, conditions, and parameters influence the therapeutic effects of IR, including fluence, irradiance, treatment timing and repetition, pulsing, and wavelength. Increasing evidence suggests that IR can carry out photostimulation and photobiomodulation effects particularly benefiting neural stimulation, wound healing, and cancer treatment. Nerve cells respond particularly well to IR, which has been proposed for a range of neurostimulation and neuromodulation applications, and recent progress in neural stimulation and regeneration are discussed in this review. The applications of IR therapy have moved on rapidly in recent years. For example, IR therapy has been developed that does not actually require an external power source, such as IR-emitting materials, and garments that can be powered by body heat alone. Another area of interest is the possible involvement of solar IR radiation in photoaging or photorejuvenation as opposites sides of the coin, and whether sunscreens should protect against solar IR? A better understanding of new developments and biological implications of IR could help us to improve therapeutic effectiveness or develop new methods of PBM using IR wavelengths. Copyright © 2016. Published by Elsevier B.V.

  7. Differentiation between probiotic and wild-type Bacillus cereus isolates by antibiotic susceptibility test and Fourier transform infrared spectroscopy (FT-IR).

    Science.gov (United States)

    Mietke, Henriette; Beer, W; Schleif, Julia; Schabert, G; Reissbrodt, R

    2010-05-30

    Animal feed often contains probiotic Bacillus strains used as feed additives. Spores of the non-pathogenic B. cereus var. toyoi (product name Toyocerin) are used. Distinguishing between toxic wild-type Bacillus cereus strains and this probiotic strain is essential for evaluating the quality and risk of feed. Bacillus cereus CIP 5832 (product name Paciflor was used as probiotic strain until 2001. The properties of the two probiotic strains are quite similar. Differentiating between probiotic strains and wild-type B. cereus strains is not easy. ss-lactam antibiotics such as penicillin and cefamandole exhibit an inhibition zone in the agar diffusion test of probiotic B. cereus strains which are not seen for wild-type strains. Therefore, performing the agar diffusion test first may make sense before FT-IR testing. When randomly checking these strains by Fourier transform infrared spectroscopy (FT-IR), the probiotic B. cereus strains were separated from wild-type B. cereus/B. thuringiensis/B. mycoides/B. weihenstephanensis strains by means of hierarchical cluster analysis. The discriminatory information was contained in the spectral windows 3000-2800 cm(-1) ("fatty acid region"), 1200-900 cm(-1) ("carbohydrate region") and 900-700 cm(-1) ("fingerprint region"). It is concluded that FT-IR spectroscopy can be used for the rapid quality control and risk analysis of animal feed containing probiotic B. cereus strains. (c) 2010 Elsevier B.V. All rights reserved.

  8. Spectra and structure of silicon containing compounds. XXXII. Raman and infrared spectra, conformational stability, vibrational assignment and ab initio calculations of n-propylsilane-d0 and Si-d3.

    Science.gov (United States)

    Durig, James R; Pan, Chunhua; Guirgis, Gamil A

    2003-03-15

    The infrared (3100-40 cm(-1)) and Raman (3100-20 cm(-1)) spectra of gaseous and solid n-propylsilane, CH(3)CH(2)CH(2)SiH(3) and the Si-d(3) isotopomer, CH(3)CH(2)CH(2)SiD(3), have been recorded. Additionally, the Raman spectra of the liquids have been recorded and qualitative depolarization values obtained. Both the anti and gauche conformers have been identified in the fluid phases but only the anti conformer remains in the solid. Variable temperature (-105 to -150 degrees C) studies of the infrared spectra of n-propylsilane dissolved in liquid krypton have been recorded and the enthalpy difference has been determined to be 220+/-22 cm(-1) (2.63+/-0.26 kJ mol(-1)) with the anti conformer the more stable form. A similar value of 234+/-23 cm(-1) (2.80+/-0.28 kJ mol(-1)) was obtained for deltaH for the Si-d(3) isotopomer. At ambient temperature it is estimated that there is 30+/-2% of the gauche conformer present. The potential function governing the conformation interchange has been estimated from the far infrared spectral data, the enthalpy difference, and the dihedral angle of the gauche conformer, which is compared to the one predicted from ab initio MP2/6-31G(d) calculations. The barriers to conformational interchange are: 942, 970 and 716 cm(-1) for the anti to gauche, gauche to gauche, and gauche to anti conformers, respectively. Relatively complete vibrational assignments are proposed for both the n-propylsilane-d(0) and Si-d(3) molecules based on the relative infrared and Raman spectral intensities, infrared band contours, depolarization ratios, and normal coordinate calculations. The geometrical parameters, harmonic force constants, vibrational frequencies, infrared intensities, Raman activities and depolarization ratios, and energy differences have been obtained for the anti and gauche conformers from ab initio MP2/6-31G(d) calculations. Structural parameters and energy differences have also been obtained utilizing the larger 6-311 + G(d,p) and 6-311 + G(2

  9. Spectra and structure of silicon containing compounds. XXXII. Raman and infrared spectra, conformational stability, vibrational assignment and ab initio calculations of n-propylsilane-d 0 and Si-d 3

    Science.gov (United States)

    Durig, James R.; Pan, Chunhua; Guirgis, Gamil A.

    2003-03-01

    The infrared (3100-40 cm -1) and Raman (3100-20 cm -1) spectra of gaseous and solid n-propylsilane, CH 3CH 2CH 2SiH 3 and the Si-d 3 isotopomer, CH 3CH 2CH 2SiD 3, have been recorded. Additionally, the Raman spectra of the liquids have been recorded and qualitative depolarization values obtained. Both the anti and gauche conformers have been identified in the fluid phases but only the anti conformer remains in the solid. Variable temperature (-105 to -150 °C) studies of the infrared spectra of n-propylsilane dissolved in liquid krypton have been recorded and the enthalpy difference has been determined to be 220±22 cm -1 (2.63±0.26 kJ mol -1) with the anti conformer the more stable form. A similar value of 234±23 cm -1 (2.80±0.28 kJ mol -1) was obtained for Δ H for the Si-d 3 isotopomer. At ambient temperature it is estimated that there is 30±2% of the gauche conformer present. The potential function governing the conformation interchange has been estimated from the far infrared spectral data, the enthalpy difference, and the dihedral angle of the gauche conformer, which is compared to the one predicted from ab initio MP2/6-31G(d) calculations. The barriers to conformational interchange are: 942, 970 and 716 cm -1 for the anti to gauche, gauche to gauche, and gauche to anti conformers, respectively. Relatively complete vibrational assignments are proposed for both the n-propylsilane-d 0 and Si-d 3 molecules based on the relative infrared and Raman spectral intensities, infrared band contours, depolarization ratios, and normal coordinate calculations. The geometrical parameters, harmonic force constants, vibrational frequencies, infrared intensities, Raman activities and depolarization ratios, and energy differences have been obtained for the anti and gauche conformers from ab initio MP2/6-31G(d) calculations. Structural parameters and energy differences have also been obtained utilizing the larger 6-311+G(d,p) and 6-311+G(2d,2p) basis sets. From the isolated

  10. Feasibility study of 2D thick-slice MR digital subtraction angiography

    International Nuclear Information System (INIS)

    Ishimori, Yoshiyuki; Takeuchi, Miho; Higashimura, Kyouji; Komuro, Hiroyuki

    2000-01-01

    Conditions required to perform contrast MR digital subtraction angiography using a two-dimensional thick-slice high-speed gradient echo were investigated. The conditions in the phantom experiment included: slice profile, flip angle, imaging matrix, fat suppression, duration of IR pulse and frequency selectivity, flip angle of IR pulse and inversion time. Based on the results of the experiment, 2D thick-slice MRDSA was performed in volunteers. Under TR/TE=5.3-9/1.3-1.8 ms conditions, the requirements were a slice thick enough to include the target region, a flip angle of 10 degrees, and a phase matrix of 96 or more. Fat suppression was required for adipose-tissue-rich regions, such as the abdomen. The optimal conditions for applying the IR preparation pulse of the IR prepped fast gradient recalled echo as spectrally selective inversion recovery appeared to be: duration of IR pulse =20 ms, flip angle =100 degrees, and inversion time =40 ms. The authors concluded that it was feasible to perform 2D thick-slice MRDSA with time resolution within 1 second. (K.H.)

  11. Thermolysis of (1R,2R)-1,2-dideuteriocyclobutane. An application of vibrational circular dichroism to kinetic analysis

    International Nuclear Information System (INIS)

    Chickos, J.S.; Annamalai, A.; Keiderling, T.A.

    1986-01-01

    The relative rates of geometric isomerization to racemization have been studied for the title compound by using a combination of infrared (IR) and vibrational circular dichroism (VCD) spectroscopies, respectively. The results are interpreted with a kinetic and mechanistic scheme which parallels that used by Berson, Pedersen, and Carpenter on a similar study of chiral cyclopropane-d 2 thermolysis. Relative rates of isomerization to stereomutation of 1.5 +/- 0.4 were obtained which can be interpreted to be consistent with a mechanism best described by random methylene rotation in tetramethylene-d 2 . This is the first application of VCD to kinetic analysis, and the advantages of IR techniques over the more usually employed UV spectroscopies to this type of basic mechanistic problem are illustrated

  12. Volumetry and biomechanical parameters detected by 3D and 2D ultrasound in patients with and without an abdominal aortic aneurysm.

    Science.gov (United States)

    Batagini, Nayara Cioffi; Ventura, Carlos Augusto Pinto; Raghavan, Madhavan L; Chammas, Maria Cristina; Tachibana, Adriano; da Silva, Erasmo Simão

    2016-06-01

    The objective was to demonstrate the ability of ultrasound (US) with 3D properties to evaluate volumetry and biomechanical parameters of the aorta in patients with and without abdominal aortic aneurysm (AAA). Thirty-one patients with normal aortas (group 1), 46 patients with AAA measuring 3.0-5.5 cm (group 2) and 31 patients with AAA ⩾ 5.5 cm (group 3) underwent a 2D/3D-US examination of the infra-renal aorta, and the images were post-processed prior to being analyzed. In the maximum diameter, the global circumferential strain and the global maximum rotation assessed by 2D speckle-tracking algorithms were compared among the three groups. The volumetry data obtained using 3D-US from 40 AAA patients were compared with the volumetry data obtained by a contemporary computed tomography (CT) scan. The median global circumferential strain was 2.0% (interquartile range (IR): 1.0-3.0), 1.0% (IR: 1.0-2.0) and 1.0% (IR: 1.0-1.75) in groups 1, 2 and 3, respectively (p volumetry and biomechanical characteristics of AAA. © The Author(s) 2016.

  13. The infra-red spectrum of the molecular dication (doubly positively charged molecule) D35Cl2+

    International Nuclear Information System (INIS)

    Abusen, R.A.

    1999-07-01

    The ion-beam/laser-beam spectrometer used in this work was designed, built and commissioned for the experimental investigation of doubly charged molecular species [Shiell 1995]. Using this spectrometer the photodissociation spectrum of the X 3 Σ - state of the molecular dication D 35 Cl 2+ was measured in the infrared. It has not yet been possible to assign and fit the observed transitions in the usual way, but comparisons of our spectra with ab-initio generated spectra show good agreement and form the basis for our preliminary assignments. Our preliminary analysis shows a good agreement between the measured spectra and an ab-initio theoretical spectra of the ν = 2-1 band, including the rotational constants and tunneling lifetimes, calculated from the potential energy of Bennett and McNab [1995]. The theoretical spectrum was brought into agreement with the measured spectra by moving its band origin by -21.1 cm -1 . The theoretical rotational constants that give good agreement with the spectrum are (in cm -1 ) B'' = 3.898, D'' = 3.561, H'' = 1.04 x 10 -9 , B' = 3.648, D' = 3.163 x 10 -4 , H' = -9.269 x 10 -8 . The shifted origin of the ν = 2-1 band is 994.3 cm -1 . A Fortran computer program was written to simulate 3Σ-3Σ vibration-rotation spectra. The theoretical spectrum obtained with this computer program has been compared with our measured spectrum. Our experimentally measured line widths and wavenumbers have been compared with the ab-initio theoretical spectrum and a good agreement obtained. This is good evidence that we are observing the ν=2-1 band of D 35 CI 2+ in the ground electronic state (X 3 Σ - state). Good agreement between measured and predicted hyperfine patterns was found using a Fermi contact constant (for the chlorine nucleus) of 190 MHz. (author)

  14. An overview on the research of Sr2IrO4-based system probed by X-ray absorption spectroscopy

    Science.gov (United States)

    Cheng, Jie; Zhu, Chaomin; Ma, Jingyuan; Wang, Yu; Liu, Shengli

    2018-03-01

    Investigations of materials with 5d transition metal ions have opened up new paradigms in condensed-matter physics because of their large spin-orbit coupling (SOC) interactions. The typical compound is Sr2IrO4, which attracted much attention due to its similarities to the parent compound of high-Tc cuprate superconductor La2CuO4. Theoretical calculations predicted that the unconventional superconductivity can occur in carrier doped-Sr2IrO4 system. Until now, hundreds of experimental methods were devoted to investigate the carrier doping effect on Sr2IrO4. Synchrotron radiation-based X-ray absorption spectroscopy (XAS) made great contributions to the local lattice and electronic structure, and also the intimate relationship between the local structure and physical properties induced by carrier doping. The aim of this review is a short introduction to the progress of research on Sr2IrO4-based system probed by the unique technique — XAS, including the strength of the SOC, valence changes upon doping and even local lattice structure with atomic level for this Sr2IrO4-based family.

  15. Effects of Dioscorea esculenta and Eubacterium rectale on insulin receptor substrate 1 (Irs1 Expression in skeletal muscle and homeostatic model assessment-insulin resistance (HOMA-IR in diabetic rats

    Directory of Open Access Journals (Sweden)

    . Sunarti

    2017-01-01

    Full Text Available Low expression of insulin receptor substrate 1 (Irs1 is associated with insulin resistance and type 2 diabetes mellitus (type 2 DM. This study was performed to evaluate the effects of Dioscorea esculenta and Eubacterium rectale on the Irs1 expression in the skeletal muscle and the homeostatic model assessment-insulin resistance (HOMA-IR of diabetic rats. Twenty-five male Wistar rats were divided into five groups i.e. non diabetic rats Group 1; diabetic rats as Group 2; diabetic rats + D. esculenta as Group 3; diabetic rats + E.rectale as Group 4 and diabetic rats + both E. rectale and D. esculenta as Group 5. Rats were made diabetic with induction of intraperitoneally injection of nicotinamide and streptozotocin. After four weeks of the interventions, the blood and skeletal muscles were taken. The Irs1 expression was analyzed with immunohistochemical staining, plasma glucose levels was analyzed using a spectrophotometer, and insulin was analyzed using ELISA methods. All intervention groups reduced plasma glucose levels and HOMA-IRs (p<0.001 and increased Irs1 expression. The greatest reduction of  plasma glucose levels and increase of Irs1 expression in the skeletal muscle were found in Group 4, however, the lowest of HOMA-IR was seen in Group 5. These results suggested that D.esculenta, E.rectale, and the combination reduced plasma glucose levels and HOMA-IR by increasing Irs1 expression in skeletal muscle.

  16. 2D surface temperature measurement of plasma facing components with modulated active pyrometry

    International Nuclear Information System (INIS)

    Amiel, S.; Loarer, T.; Pocheau, C.; Roche, H.; Gauthier, E.; Aumeunier, M.-H.; Courtois, X.; Jouve, M.; Balorin, C.; Moncada, V.; Le Niliot, C.; Rigollet, F.

    2014-01-01

    In nuclear fusion devices, such as Tore Supra, the plasma facing components (PFC) are in carbon. Such components are exposed to very high heat flux and the surface temperature measurement is mandatory for the safety of the device and also for efficient plasma scenario development. Besides this measurement is essential to evaluate these heat fluxes for a better knowledge of the physics of plasma-wall interaction, it is also required to monitor the fatigue of PFCs. Infrared system (IR) is used to manage to measure surface temperature in real time. For carbon PFCs, the emissivity is high and known (ε ∼ 0.8), therefore the contribution of the reflected flux from environment and collected by the IR cameras can be neglected. However, the future tokamaks such as WEST and ITER will be equipped with PFCs in metal (W and Be/W, respectively) with low and variable emissivities (ε ∼ 0.1–0.4). Consequently, the reflected flux will contribute significantly in the collected flux by IR camera. The modulated active pyrometry, using a bicolor camera, proposed in this paper allows a 2D surface temperature measurement independently of the reflected fluxes and the emissivity. Experimental results with Tungsten sample are reported and compared with simultaneous measurement performed with classical pyrometry (monochromatic and bichromatic) with and without reflective flux demonstrating the efficiency of this method for surface temperature measurement independently of the reflected flux and the emissivity

  17. GOODS-HERSCHEL: SEPARATING HIGH-REDSHIFT ACTIVE GALACTIC NUCLEI AND STAR-FORMING GALAXIES USING INFRARED COLOR DIAGNOSTICS

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, Allison; Pope, Alexandra [Department of Astronomy, University of Massachusetts, Amherst, MA 01002 (United States); Charmandaris, Vassilis [Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, GR-71003, Heraklion (Greece); Daddi, Emmanuele; Elbaz, David; Pannella, Maurilio; Aussel, Herve; Dasyra, Kalliopi; Leiton, Roger [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, Irfu/SAp, Orme des Merisiers, F-91191 Gif-sur-Yvette (France); Hwang, Ho Seong [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Scott, Douglas; Magnelli, Benjamin; Popesso, Paola [Max-Planck-Institut fuer Extraterrestrische Physik (MPE), Postfach 1312, D-85741, Garching (Germany); Altieri, Bruno; Coia, Daniela; Valtchanov, Ivan [Herschel Science Centre, European Space Astronomy Centre, Villanueva de la Canada, E-28691 Madrid (Spain); Dannerbauer, Helmut [Universitaet Wien, Institut fuer Astrophysik, Tuerkenschanzstrasse 17, A-1180 Wien (Austria); Dickinson, Mark; Kartaltepe, Jeyhan [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Magdis, Georgios [Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)

    2013-02-15

    We have compiled a large sample of 151 high-redshift (z = 0.5-4) galaxies selected at 24 {mu}m (S {sub 24} > 100 {mu}Jy) in the GOODS-N and ECDFS fields for which we have deep Spitzer IRS spectroscopy, allowing us to decompose the mid-infrared spectrum into contributions from star formation and activity in the galactic nuclei. In addition, we have a wealth of photometric data from Spitzer IRAC/MIPS and Herschel PACS/SPIRE. We explore how effective different infrared color combinations are at separating our mid-IR spectroscopically determined active galactic nuclei from our star-forming galaxies. We look in depth at existing IRAC color diagnostics, and we explore new color-color diagnostics combining mid-IR, far-IR, and near-IR photometry, since these combinations provide the most detail about the shape of a source's IR spectrum. An added benefit of using a color that combines far-IR and mid-IR photometry is that it is indicative of the power source driving the IR luminosity. For our data set, the optimal color selections are S {sub 250}/S {sub 24} versus S {sub 8}/S {sub 3.6} and S {sub 100}/S {sub 24} versus S {sub 8}/S {sub 3.6}; both diagnostics have {approx}10% contamination rate in the regions occupied primarily by star-forming galaxies and active galactic nuclei, respectively. Based on the low contamination rate, these two new IR color-color diagnostics are ideal for estimating both the mid-IR power source of a galaxy when spectroscopy is unavailable and the dominant power source contributing to the IR luminosity. In the absence of far-IR data, we present color diagnostics using the Wide-field Infrared Survey Explorer mid-IR bands which can efficiently select out high-z (z {approx} 2) star-forming galaxies.

  18. A first-principles study of oxygen adsorption on Ir(111) surface

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Hengjiao, E-mail: gaohengjiao@163.com; Xiong, Yuqing, E-mail: xiongyq@hotmail.com; Liu, Xiaoli, E-mail: shantianzi@126.com; Zhao, Dongcai, E-mail: zhaodongc@163.com; Feng, Yudong, E-mail: yudong_feng@sina.com; Wang, Lanxi, E-mail: wanglanxi@live.com; Wang, Jinxiao, E-mail: coldwind716@gmail.com

    2016-12-15

    Highlights: • Adsorption of oxygen on Ir(111) surface was studied by density functional theory. • The most stable adsorption site was determined by adsorption energy calculation. • Adsorption of oxygen at bridge and top site on Ir surface was the most stable ones. • Interaction of O 2p and Ir 5d orbits is relatively strong and formed hybridization. - Abstract: In order to understand deposition mechanism of iridium thin film by atomic layer deposition, the adsorption of oxygen on Ir(111) surface was studied by use of density functional theory and a periodical slab model. By calculating the adsorption energy and structure of oxygen at four adsorption sites (top, bridge, fcc-hollow and hcp-hollow) on Ir(111) surface, the most stable adsorption site was determined. On this basis, the banding mechanism of O and Ir atoms was studied by density of states of oxygen and iridium atoms. Oxygen adsorbed at hcp(parallel) site on Ir(111) surface was the most stable one according to the adsorption energy calculation results. Orbital charge analysis indicate that charge transferred from 5p and 5d orbit to 2p orbit of adsorbed O atoms, and 6s orbit of iridium atoms. Meanwhile, density of state study indicated that adsorption of oxygen on Ir(111) surface is mainly due to the interaction between 2p orbit of O atoms and 5d orbit of iridium atoms.

  19. Thermodynamics of interacting holographic dark energy with the apparent horizon as an IR cutoff

    International Nuclear Information System (INIS)

    Sheykhi, Ahmad

    2010-01-01

    As soon as an interaction between holographic dark energy and dark matter is taken into account, the identification of an IR cutoff with the Hubble radius H -1 , in a flat universe, can simultaneously drive accelerated expansion and solve the coincidence problem. Based on this, we demonstrate that in a non-flat universe the natural choice for the IR cutoff could be the apparent horizon radius, r-tilde A =1/√(H 2 +k/a 2 ). We show that any interaction of dark matter with holographic dark energy, whose infrared cutoff is set by the apparent horizon radius, implies an accelerated expansion and a constant ratio of the energy densities of both components thus solving the coincidence problem. We also verify that for a universe filled with dark energy and dark matter, the Friedmann equation can be written in the form of the modified first law of thermodynamics, dE = T h dS h + WdV, at the apparent horizon. In addition, the generalized second law of thermodynamics is fulfilled in a region enclosed by the apparent horizon. These results hold regardless of the specific form of dark energy and interaction term. Our study might reveal that in an accelerating universe with spatial curvature, the apparent horizon is a physical boundary from the thermodynamical point of view.

  20. 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)

  1. 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.

  2. Dehydration of a layered double hydroxide-C2AH8

    International Nuclear Information System (INIS)

    Ukrainczyk, N.; Matusinovic, T.; Kurajica, S.; Zimmermann, B.; Sipusic, J.

    2007-01-01

    Thermal dehydration of dicalcium aluminate hydrate, C 2 AH 8 , has been investigated by simultaneous differential thermal and thermo gravimetric analysis (DTA/TGA), powder X-ray diffraction (XRD), temperature-dependent infrared spectroscopy (FT-IR), and BET method of surface area measurement. The temperature-dependent infrared measurements were studied by two-dimensional infrared (2D-IR) correlation spectroscopy. The structure of aluminum-oxide polyhedron, characterized by 27 Al solid state NMR spectrum method and FT-IR, shows tetrahedron and octahedron as the main forms of aluminum-oxide polyhedrons in C 2 AH 8 sample. From the results obtained a variety of structural transformations observed are explained as a consequence of the removal of loosely held interlayer water molecules at lower temperatures, followed by grafting process of the interlayer [Al(OH) 4 ] - anion. Structural model of a grafting process of the interlayer [Al(OH) 4 ] - tetrahedron onto hydroxylated octahedrons of [Ca 2 Al(OH) 6 ] + layers has been proposed in order to explain observed loss of one water molecule, shrinkage of interlayer spacing and qualitative changes of FT-IR spectra. At higher temperatures the dehydroxylation of the lattice and decomposition of the interlayer species occurs, yielding amorphous material that crystallizes into C 3 A and C 12 A 7 at 885 deg. C. Those findings provide improvement in the interpretation of thermo-analytical results of calcium aluminate cements (CAC) hydration products, and better understanding of CAC conversion process

  3. Quantitative infrared and near-infrared gas-phase spectra for pyridine: Absolute intensities and vibrational assignments

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, T. J.; Aker, P. M.; Scharko, N. K.; Williams, S. D.

    2018-02-01

    Using vetted methods for generating quantitative absorption reference data, broadband infrared and near-infrared spectra (total range 11,000 – 600 cm-1) of pyridine vapor were recorded at 0.1 cm-1 spectral resolution, with the analyte thermostatted at 298 K and pressure-broadened to 1 atmosphere using N2 ballast gas. The quantitative spectrum is reported for the first time, and we have re-assigned some of the 27 fundamental modes. Fundamental assignments were confirmed by IR vapor phase band shapes, FT-Raman measurements and comparison with previous analyses. For the 760-Torr vapor-phase IR data several bands show resolved peaks (Q-branches). We have also assigned for the first time hundreds of combination and overtone bands in the mid- and near-IR. All assignments were made via comparison to theoretically calculated frequencies and intensities: The frequencies were computed with Gaussian03 with the anharmonic option, using MP2 and the ccpvtz basis set. The intensities were taken from a VSCF calculation in GAMESS using Hartree-Fock (for overtones and combination bands) or from the harmonic MP2 for fundamentals. Overtone and combination band harmonic and anharmonic frequencies, as well as intensities were also calculated using the CFOUR program. It is seen in the NIR spectrum near 6000 cm-1 that the very strong bands arise from the C-H first overtones, whereas only much weaker bands are observed for combination bands of C-H stretching modes. Certain features are discussed for their potential utility for atmospheric monitoring.

  4. 3D positioning scheme exploiting nano-scale IR-UWB orthogonal pulses

    Directory of Open Access Journals (Sweden)

    Kim Nammoon

    2011-01-01

    Full Text Available Abstract In these days, the development of positioning technology for realizing ubiquitous environments has become one of the most important issues. The Global Positioning System (GPS is a well-known positioning scheme, but it is not suitable for positioning in in-door/building environments because it is difficult to maintain line-of-sight condition between satellites and a GPS receiver. To such problem, various positioning methods such as RFID, WLAN, ZigBee, and Bluetooth have been developed for indoor positioning scheme. However, the majority of positioning schemes are focused on the two-dimension positioning even though three-dimension (3D positioning information is more useful especially in indoor applications, such as smart space, U-health service, context aware service, etc. In this paper, a 3D positioning system based on mutually orthogonal nano-scale impulse radio ultra-wideband (IR-UWB signals and cross array antenna is proposed. The proposed scheme uses nano-scale IR-UWB signals providing fine time resolution and high-resolution multiple signal specification algorithm for the time-of-arrival and the angle-of-arrival estimation. The performance is evaluated over various IEEE 802.15.4a channel models, and simulation results show the effectiveness of proposed scheme.

  5. 4PS/insulin receptor substrate (IRS)-2 is the alternative substrate of the insulin receptor in IRS-1-deficient mice.

    Science.gov (United States)

    Patti, M E; Sun, X J; Bruening, J C; Araki, E; Lipes, M A; White, M F; Kahn, C R

    1995-10-20

    Insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate of the insulin and insulin-like growth factor (IGF)-1 receptors. Transgenic mice lacking IRS-1 are resistant to insulin and IGF-1, but exhibit significant residual insulin action which corresponds to the presence of an alternative high molecular weight substrate in liver and muscle. Recently, Sun et al. (Sun, X.-J., Wang, L.-M., Zhang, Y., Yenush, L. P., Myers, M. G., Jr., Glasheen, E., Lane, W.S., Pierce, J. H., and White, M. F. (1995) Nature 377, 173-177) purified and cloned 4PS, the major substrate of the IL-4 receptor-associated tyrosine kinase in myeloid cells, which has significant structural similarity to IRS-1. To determine if 4PS is the alternative substrate of the insulin receptor in IRS-1-deficient mice, we performed immunoprecipitation, immunoblotting, and phosphatidylinositol (PI) 3-kinase assays using specific antibodies to 4PS. Following insulin stimulation, 4PS is rapidly phosphorylated in liver and muscle, binds to the p85 subunit of PI 3-kinase, and activates the enzyme. Insulin stimulation also results in the association of 4PS with Grb 2 in both liver and muscle. In IRS-1-deficient mice, both the phosphorylation of 4PS and associated PI 3-kinase activity are enhanced, without an increase in protein expression. Immunodepletion of 4PS from liver and muscle homogenates removes most of the phosphotyrosine-associated PI 3-kinase activity in IRS-1-deficient mice. Thus, 4PS is the primary alternative substrate, i.e. IRS-2, which plays a major role in physiologic insulin signal transduction via both PI 3-kinase activation and Grb 2/Sos association. In IRS-1-deficient mice, 4PS/IRS-2 provides signal transduction to these two major pathways of insulin signaling.

  6. RISING FROM THE ASHES: MID-INFRARED RE-BRIGHTENING OF THE IMPOSTOR SN 2010da IN NGC 300

    Energy Technology Data Exchange (ETDEWEB)

    Lau, Ryan M.; Ressler, Michael E. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Kasliwal, Mansi M.; Jencson, Jacob [California Institute of Technology, Pasadena, CA 91125 (United States); Bond, Howard E.; Monson, Andrew J. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Smith, Nathan [Steward Observatory, University of Arizona, Tuscon, AZ 85721 (United States); Fox, Ori D. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Carlon, Robert; Dykhoff, Devin; Gehrz, Robert [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, SE, University of Minnesota, Minneapolis, MN 55455 (United States); Cody, Ann Marie [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Contreras, Carlos [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Hsiao, Eric [Department of Physics, Florida State University, 77 Chieftain Way, Tallahassee, FL 32306 (United States); Khan, Rubab [NASA Goddard Space Flight Center, MC 665, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States); Masci, Frank [Infrared Processing and Analysis Center, California Institute of Technology, M/S 100-22, Pasadena, CA 91125 (United States); Monard, L. A. G. [Bronberg and Kleinkaroo Observatories, P.O. Box 281, Calitzdorp 6660, Western Cape (South Africa); Morrell, Nidia; Phillips, Mark [Carnegie Institution of Washington, Las Campanas Observatory, Colina el Pino, Casilla 601, La Serena (Chile)

    2016-10-20

    We present multi-epoch mid-infrared (IR) photometry and the optical discovery observations of the “impostor” supernova (SN) 2010da in NGC 300 using new and archival Spitzer Space Telescope images and ground-based observatories. The mid-infrared counterpart of SN 2010da was detected as Spitzer Infrared Intensive Transient Survey (SPIRITS) 14bme in the SPIRITS, an ongoing systematic search for IR transients. Before erupting on 2010 May 24, the SN 2010da progenitor exhibited a constant mid-IR flux at 3.6 and only a slight ∼10% decrease at 4.5 μ m between 2003 November and 2007 December. A sharp increase in the 3.6 μ m flux followed by a rapid decrease measured ∼150 days before and ∼80 days after the initial outburst, respectively, reveal a mid-IR counterpart to the coincident optical and high luminosity X-ray outbursts. At late times, after the outburst (∼2000 days), the 3.6 and 4.5 μ m emission increased to over a factor of two times the progenitor flux and is currently observed (as of 2016 Feb) to be fading, but still above the progenitor flux. We attribute the re-brightening mid-IR emission to continued dust production and increasing luminosity of the surviving system associated with SN 2010da. We analyze the evolution of the dust temperature ( T {sub d} ∼ 700–1000 K), mass ( M {sub d} ∼ 0.5–3.8 × 10{sup −7} M {sub ⊙}), luminosity ( L {sub IR} ∼ 1.3–3.5 × 10{sup 4} L {sub ⊙}), and the equilibrium temperature radius ( R {sub eq} ∼ 6.4–12.2 au) in order to resolve the nature of SN 2010da. We address the leading interpretation of SN 2010da as an eruption from a luminous blue variable high-mass X-ray binary (HMXB) system. We propose that SN 2010da is instead a supergiant (sg)B[e]-HMXB based on similar luminosities and dust masses exhibited by two other known sgB[e]-HMXB systems. Additionally, the SN 2010da progenitor occupies a similar region on a mid-IR color–magnitude diagram (CMD) with known sgB[e] stars in the Large

  7. The most reactive third-row transition metal: Guided ion beam and theoretical studies of the activation of methane by Ir+

    Science.gov (United States)

    Li, Feng-Xia; Zhang, Xiao-Guang; Armentrout, P. B.

    2006-09-01

    The potential energy surface for activation of methane by the third-row transition metal cation, Ir+, is studied experimentally by examining the kinetic energy dependence of reactions of Ir+ with methane, IrCH2+ with H2 and D2, and collision-induced dissociation of IrCH2+ with Xe using guided ion beam tandem mass spectrometry. A flow tube ion source produces Ir+ in its electronic ground state term and primarily in the ground spin-orbit level. We find that dehydrogenation to form IrCH2+ + H2 is exothermic, efficient, and the only process observed at low energies for reaction of Ir+ with methane, whereas IrH+ dominates the product spectrum at higher energies. We also observe the IrH2+ product, which provides evidence that methane activation proceeds via a dihydride (H)2IrCH2+ intermediate. The kinetic energy dependences of the cross sections for several endothermic reactions are analyzed to give 0 K bond dissociation energies (in eV) of D0(Ir+-2H) > 5.09 +/- 0.07, D0(Ir+-C) = 6.59 +/- 0.05, D0(Ir+-CH) = 6.91 +/- 0.23, and D0(Ir+-CH3) = 3.25 +/- 0.18. D0(Ir+-CH2) = 4.92 +/- 0.03 eV is determined by measuring the forward and reverse reaction rates for Ir++CH4[right harpoon over left]IrCH2++H2 at thermal energy. Ab initio calculations at the B3LYP/HW+/6-311++G(3df,3p) level performed here show reasonable agreement with the experimental bond energies and with the few previous experimental and theoretical values available. Theory also provides the electronic structures of the product species as well as intermediates and transition states along the reactive potential energy surfaces. We also compare this third-row transition metal system with the first-row and second-row congeners, Co+ and Rh+. Differences in reactivity and mechanisms can be explained by the lanthanide contraction and relativistic effects that alter the relative size of the valence s and d orbitals.

  8. The infrared spectrum of asteroid 433 Eros

    Science.gov (United States)

    Larson, H. P.; Fink, U.; Treffers, R. R.; Gautier, T. N., III

    1976-01-01

    The mineralogical composition of asteroid Eros has been determined from its infrared spectrum (0.9-2.7 micrometers; 28/cm resolution). Major minerals include metallic Ni-Fe and pyroxene; no spectroscopic evidence for olivine or plagioclase feldspar was found. The IR spectrum of Eros is most consistent with a stony-iron composition.

  9. A subset of sweet-sensing neurons identified by IR56d are necessary and sufficient for fatty acid taste.

    Directory of Open Access Journals (Sweden)

    John M Tauber

    2017-11-01

    Full Text Available Fat represents a calorically potent food source that yields approximately twice the amount of energy as carbohydrates or proteins per unit of mass. The highly palatable taste of free fatty acids (FAs, one of the building blocks of fat, promotes food consumption, activates reward circuitry, and is thought to contribute to hedonic feeding underlying many metabolism-related disorders. Despite a role in the etiology of metabolic diseases, little is known about how dietary fats are detected by the gustatory system to promote feeding. Previously, we showed that a broad population of sugar-sensing taste neurons expressing Gustatory Receptor 64f (Gr64f is required for reflexive feeding responses to both FAs and sugars. Here, we report a genetic silencing screen to identify specific populations of taste neurons that mediate fatty acid (FA taste. We find neurons identified by expression of Ionotropic Receptor 56d (IR56d are necessary and sufficient for reflexive feeding response to FAs. Functional imaging reveals that IR56d-expressing neurons are responsive to short- and medium-chain FAs. Silencing IR56d neurons selectively abolishes FA taste, and their activation is sufficient to drive feeding responses. Analysis of co-expression with Gr64f identifies two subpopulations of IR56d-expressing neurons. While physiological imaging reveals that both populations are responsive to FAs, IR56d/Gr64f neurons are activated by medium-chain FAs and are sufficient for reflexive feeding response to FAs. Moreover, flies can discriminate between sugar and FAs in an aversive taste memory assay, indicating that FA taste is a unique modality in Drosophila. Taken together, these findings localize FA taste within the Drosophila gustatory center and provide an opportunity to investigate discrimination between different categories of appetitive tastants.

  10. A subset of sweet-sensing neurons identified by IR56d are necessary and sufficient for fatty acid taste.

    Science.gov (United States)

    Tauber, John M; Brown, Elizabeth B; Li, Yuanyuan; Yurgel, Maria E; Masek, Pavel; Keene, Alex C

    2017-11-01

    Fat represents a calorically potent food source that yields approximately twice the amount of energy as carbohydrates or proteins per unit of mass. The highly palatable taste of free fatty acids (FAs), one of the building blocks of fat, promotes food consumption, activates reward circuitry, and is thought to contribute to hedonic feeding underlying many metabolism-related disorders. Despite a role in the etiology of metabolic diseases, little is known about how dietary fats are detected by the gustatory system to promote feeding. Previously, we showed that a broad population of sugar-sensing taste neurons expressing Gustatory Receptor 64f (Gr64f) is required for reflexive feeding responses to both FAs and sugars. Here, we report a genetic silencing screen to identify specific populations of taste neurons that mediate fatty acid (FA) taste. We find neurons identified by expression of Ionotropic Receptor 56d (IR56d) are necessary and sufficient for reflexive feeding response to FAs. Functional imaging reveals that IR56d-expressing neurons are responsive to short- and medium-chain FAs. Silencing IR56d neurons selectively abolishes FA taste, and their activation is sufficient to drive feeding responses. Analysis of co-expression with Gr64f identifies two subpopulations of IR56d-expressing neurons. While physiological imaging reveals that both populations are responsive to FAs, IR56d/Gr64f neurons are activated by medium-chain FAs and are sufficient for reflexive feeding response to FAs. Moreover, flies can discriminate between sugar and FAs in an aversive taste memory assay, indicating that FA taste is a unique modality in Drosophila. Taken together, these findings localize FA taste within the Drosophila gustatory center and provide an opportunity to investigate discrimination between different categories of appetitive tastants.

  11. Diogenite-like Features in the Spitzer IRS (5-35 micrometers) Spectrum of 956 ELISA

    Science.gov (United States)

    Lim, Lucy F.; Emery, Joshua P.; Moskovitz, Nicholas A.

    2009-01-01

    We report preliminary results from the Spitzer Infrared Spectrograph (IRS) observations of the V-type asteroid 956 Elisa. Elisa was observed as part of a campaign to measure the 5.2-38 micron spectra of small basaltic asteroids with the Spitzer IRS. Targets include members of the dynamical family of the unique large differentiated asteroid 4 Vesta ("Vesroids"), several outer-main-belt basaltic asteroids whose orbits exclude them from originating on 4 Vesta, and the basaltic near-Earth asteroid 4055 Magellan.

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

    Science.gov (United States)

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

    2016-03-01

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

  13. Infrared absorption of human breast tissues in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Liu Chenglin [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Physics Department of Yancheng Teachers' College, Yancheng 224002 (China); Zhang Yuan [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Yan Xiaohui [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China); Zhang Xinyi [Department of Physics, Surface Physics Laboratory (National Key laboratory), Synchrotron Radiation Research Center, Fudan University, Shanghai 200433 (China) and Shanghai Research Center of Acupuncture and Meridian, Pudong, Shanghai 201203 (China)]. E-mail: xy-zhang@fudan.edu.cn; Li Chengxiang [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Yang Wentao [Cancer Hospital, Medical Center, Fudan University, Shanghai 200032 (China); Shi Daren [Cancer Hospital, Medical Center, Fudan University, Shanghai 200032 (China)

    2006-07-15

    The spectral characteristics of human breast tissues in normal status and during different cancerous stages have been investigated by synchrotron radiation based Fourier transform infrared (SR-FTIR) absorption spectroscopy. Thanks to the excellent synchrotron radiation infrared (IR) source, higher resolving power is achieved in SR-FTIR absorption spectra than in conventional IR absorption measurements. Obvious variations in IR absorption spectrum of breast tissues were found as they change from healthy to diseased, or say in progression to cancer. On the other hand, some specific absorption peaks were found in breast cancer tissues by SR-FTIR spectroscopic methods. These spectral characteristics of breast tissue may help us in early diagnosis of breast cancer.

  14. Discrimination of Chinese Sauce liquor using FT-IR and two-dimensional correlation IR spectroscopy

    Science.gov (United States)

    Sun, Su-Qin; Li, Chang-Wen; Wei, Ji-Ping; Zhou, Qun; Noda, Isao

    2006-11-01

    We applied the three-step IR macro-fingerprint identification method to obtain the IR characteristic fingerprints of so-called Chinese Sauce liquor (Moutai liquor and Kinsly liquor) and a counterfeit Moutai. These fingerprints can be used for the identification and discrimination of similar liquor products. The comparison of their conventional IR spectra, as the first step of identification, shows that the primary difference in Sauce liquor is the intensity of characteristic peaks at 1592 and 1225 cm -1. The comparison of the second derivative IR spectra, as the second step of identification, shows that the characteristic absorption in 1400-1800 cm -1 is substantially different. The comparison of 2D-IR correlation spectra, as the third and final step of identification, can discriminate the liquors from another direction. Furthermore, the method was successfully applied to the discrimination of a counterfeit Moutai from the genuine Sauce liquor. The success of the three-step IR macro-fingerprint identification to provide a rapid and effective method for the identification of Chinese liquor suggests the potential extension of this technique to the identification and discrimination of other wine and spirits, as well.

  15. Archival Investigation of Outburst Sites and Progenitors of Extragalactic Intermediate-Luminosity Mid-IR Transients

    Science.gov (United States)

    Bond, Howard

    2017-08-01

    Our team is using Spitzer in a long-term search for extragalactic mid-infrared (MIR) variable stars and transients-the SPIRITS project (SPitzer InfraRed Intensive Transients Survey). In this first exploration of luminous astrophysical transients in the infrared, we have discovered a puzzling new class. We call them SPRITEs: eSPecially Red Intermediate-luminosity Transient Events. They have maximum MIR luminosities between supernovae and classical novae, but are not detected in the optical to deep limits. To date, we have discovered more than 50 SPRITEs in galaxies out to 17 Mpc. In this Archival Research proposal, we request support in order to investigate the pre-eruption sites in HST images of some 3 dozen SPRITEs discovered to date, and an additional 2 dozen that we are likely to find until the end of Spitzer observing in late 2018. Our aims are (1) characterize the pre-outburst environments at HST resolution in the visible and near-IR, to understand the stellar populations, stellar ages and masses, and interstellar medium at the outburst sites; (2) search for progenitors; (3) help prepare the way for a better understanding of the nature of extragalactic IR transients that will be investigated by JWST.

  16. Enhanced Activity and Durability of Nanosized Pt-SnO2/IrO2/CNTs Catalyst for Methanol Electrooxidation.

    Science.gov (United States)

    Wang, Hongjuan; Wang, Xiaohui; Zheng, Jiadao; Peng, Feng; Yu, Hao

    2015-05-01

    Pt-SnO2/IrO2/CNTs anode catalyst for direct methanol fuel cell was designed and prepared with IrO2/CNTs as support for the subsequent immobilization of Pt and SnO2 at the same time. The structure of the catalysts and their catalytic performance in methanol electrooxidation were investigated and the roles of IrO2 and SnO2 in methanol electrooxidation were discussed as well. Results show that Pt-SnO2/IrO2/CNTs catalyst exhibits the best activity and durability for methanol electrooxidation when compared with Pt/CNTs, Pt/IrO2/CNTs and Pt-SnO2/CNTs. According to the results of electrochemical tests and physicochemical characterizations, the enhancements of Pt-SnO2/IrO2/CNTs were attributed to the special properties of IrO2 and SnO2, in which IrO2 mainly increases the methanol oxidation activity and SnO2 mainly improves the CO oxidation ability and durability. Therefore, Pt-SnO2/IrO2/CNTs exhibits excellent performance for methanol oxidation with higher electrocatalytic activity (I(f) of 1054 A g(Pt(-1)) and powerful anti-poisoning ability (the onset potential for CO oxidation of 0.3 V) and outstanding durability (the sustained time t in CP of 617 s), revealing a suitable anode catalyst for DMFCs.

  17. Low background infrared (LBIR) facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Low background infrared (LBIR) facility was originally designed to calibrate user supplied blackbody sources and to characterize low-background IR detectors and...

  18. A density functional study on adsorption and dissociation of O 2 on Ir(1 0 0) surface

    Science.gov (United States)

    Erikat, I. A.; Hamad, B. A.; Khalifeh, J. M.

    2011-06-01

    The adsorption and the reaction barrier for the dissociation of O 2 on Ir(1 0 0) surface are studied using periodic self-consistent density functional theory (DFT) calculations. Dissociative adsorption is found to be energetically more favorable compared to molecular adsorption. Parallel approaches Prl1 and Prl2 on a hollow site with the same adsorption energy of -3.93 eV for both of them are found to have the most energetically preferred sites of adsorptions among all the studied cases. Hybridization between p-O 2 and d-metal orbitals is responsible for the dissociative adsorption. The minimum energy path is determined by using the nudge elastic band method (NEB). We found that the dissociation occurs immediately and very early in the dissociation path with a small activation barrier (0.26 eV), which means that molecular adsorption of O 2 on Ir(1 0 0) surface occurs at very low temperatures; this is consistent with previous experimental and theoretical studies on Ir surfaces.

  19. Report of research and investigation committee for infrared radiation heating technology. Sekigai hosha kanetsu gijutsu kenkyu chosa iinkai hokoku

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, M. (Fukuyama Univ., Hiroshima (Japan). Faculty of Engineering)

    1994-07-01

    The committee was established in July 1990 for research and investigation of infrared (IR) heating technology and finished its activity in March 1993. This report describes the committee members and the results of research and investigation. (1) Application of IR radiation (sensing): the research and investigation results were reported on the following items; the recognition of letters and patterns on cultural properties by IR radiation, the passive sensor (detecting the IR radiated from the object without emitting from the sensor), the IR image system, and the diagnosis of outer wail of buildings. (2) The following were researched on the IR radiation source and IR emitting material; multi-functional heating element having far infrared radiation function and deodorant function, the emissivity of far IR radiation, and the evaluation of the functions by the difference in emissivity. (3) The IR heating technology was described on the following: drying the persimmon using far IR radiation, the present situation of research on IR heating done by foreign power supply companies, and the feature and the application of far IR heater. In addition to these, the following were also reported; (4) measurement of IR radiation and (5) effect of living body and organism.

  20. A ZnGeP{sub 2} Optical Parametric Oscillator with Mid-IR Output Power 3 W Pumped by a Tm, Ho:GdVO{sub 4} Laser

    Energy Technology Data Exchange (ETDEWEB)

    Bao-Quan, Yao; Guo-Li, Zhu; You-Lun, Ju; Yue-Zhu, Wang [National Key Laboratory of Tunable Laser Technology, Harbin Institute of Technology, Harbin 150080 (China)

    2009-02-15

    We report an efficient mid-infrared optical parametric oscillator (OPO) pumped by a pulsed Tm,Ho-codoped GdVO4 laser. The 10-W Tm,Ho:GdVO4 laser pumped by a 801 nm diode produces 20ns pulses with a repetition rate of 10kHz at wavelength of 2.048 {mu}m. The ZnGeP{sub 2} (ZGP) OPO produces 15-ns pulses in the spectral regions 3.65-3.8 {mu}m and 4.45-4.65 {mu}m simultaneously. More than 3 W of mid-IR output power can be generated with a total OPO slope efficiency greater than 58% corresponding to incident 2 {mu}m pump power. The diode laser pump to mid-IR optical conversion efficiency is about 12%.

  1. Tuning direct bandgap GeSn/Ge quantum dots' interband and intraband useful emission wavelength: Towards CMOS compatible infrared optical devices

    Science.gov (United States)

    Baira, Mourad; Salem, Bassem; Madhar, Niyaz Ahamad; Ilahi, Bouraoui

    2018-05-01

    In this work, interband and intraband optical transitions from direct bandgap strained GeSn/Ge quantum dots are numerically tuned by evaluating the confined energies for heavy holes and electrons in D- and L-valley. The practically exploitable emission wavelength ranges for efficient use in light emission and sensing should fulfill specific criteria imposing the electrons confined states in D-valley to be sufficiently below those in L-valley. This study shows that GeSn quantum dots offer promising opportunity towards high efficient group IV based infrared optical devices operating in the mid-IR and far-IR wavelength regions.

  2. Analysis of ν2 of D 2S

    Science.gov (United States)

    Gillis, James R.; Blatherwick, Ronald D.; Bonomo, Francis S.

    1985-11-01

    The infrared spectrum of ν2 of D 2S was recorded from 740 to 1100 cm -1 on the University of Denver 50-cm FTIR spectrometer system. We have assigned 655 transitions from D 232S and 129 from D 234S, and have analyzed them using Watson's A-reduced Hamiltonian evaluated in the I r representation. We used the recently published D 232S and D 234S ground state Hamiltonian constants [C. Camy-Peyret, J. M. Flaud, L. Lechuga-Fossat and J. W. C. Johns, J. Mol. Spectrosc.109, 300-333 (1985)]. Upper state Hamiltonian constants were obtained from a fit of the ν2 transitions, keeping the ground state constants fixed while varying the upper state constants. The standard deviation of the D 232S ν2 fit is 0.0025 cm -1. The standard deviation of the D 234S ν2 fit is 0.0041 cm -1.

  3. Laboratory Infrared Spectra of Polycyclic Aromatic Nitrogen Heterocycles: Quinoline, and Phenanthridine in Solid Argon and H2O

    Science.gov (United States)

    Bernstein, M. P.; Mattioda, A. L.; Sandford, S. A.; Hudgins, D. M.

    2004-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are common throughout the universe. Their detection and identification are based on telescopic infrared (IR) spectra compared with laboratory data. Polycyclic Aromatic Nitrogen Heterocycles (PANHs) are heterocyclic aromatics i.e., PAHs with carbon atoms replaced by a nitrogen atom. These molecules should be present in the interstellar medium, but have received relatively little attention. We present mid-IR spectra of two PANHs, quinoline (C9H7N), and phenanthridine (C13H9N) isolated in solid argon and frozen in solid H2O at 12 K, conditions yielding data directly comparable to astronomical observations. In contrast to simple PAHs, that do not interact strongly with solid H2O, the nitrogen atoms in PANHs are potentially capable of hydrogen bonding with H2O. Whereas the IR spectrum of phenanthridine in H2O is similar to that of the same compound isolated in an argon matrix, quinoline absorptions shift up to 16 cm(sup -1) (0.072 mm) between argon and H2O. Thus, astronomers will not always be able to rely on IR band positions of matrix isolated PANHs to correctly interpret the absorptions of PANHs frozen in H2O ice grains. Furthermore, our data suggest that relative band areas also vary, so determining column densities to better than a factor of 3 will require knowledge of the matrix in which the PANH is embedded and laboratory studies of relevant samples.

  4. PERIODIC ACCRETION INSTABILITIES IN THE PROTOSTAR L1634 IRS 7

    Energy Technology Data Exchange (ETDEWEB)

    Hodapp, Klaus W. [Institute for Astronomy, University of Hawaii, 640 N. Aohoku Place, Hilo, HI 96720 (United States); Chini, Rolf, E-mail: hodapp@ifa.hawaii.edu, E-mail: rolf.chini@astro.ruhr-uni-bochum.de [Astronomisches Institut, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum (Germany)

    2015-11-10

    The small molecular cloud Lynds 1634 contains at least three outflow sources. We found one of these, IRS 7, to be variable with a period of 37.14 ± 0.04 days and an amplitude of approximately 2 mag in the K{sub s} band. The light curve consists of a quiescent phase with little or no variation, and a rapid outburst phase. During the outburst phase, the rapid variation in brightness generates light echoes that propagate into the surrounding molecular cloud, allowing a measurement of the distance to IRS 7 of 404 pc ± 35 pc. We observed only a marginally significant change in the H − K color during the outburst phase. The K-band spectrum of IRS 7 shows CO bandhead emission but its equivalent width does not change significantly with the phase of the light curve. The H{sub 2} 1–0 S(1) line emission does not follow the variability of the continuum flux. We also used the imaging data for a proper motion study of the outflows originating from the IRS 7 and the far-infrared source IRAS 05173-0555, and confirm that these are indeed distinct outflows.

  5. Linearly Polarized IR Spectroscopy Theory and Applications for Structural Analysis

    CERN Document Server

    Kolev, Tsonko

    2011-01-01

    A technique that is useful in the study of pharmaceutical products and biological molecules, polarization IR spectroscopy has undergone continuous development since it first emerged almost 100 years ago. Capturing the state of the science as it exists today, "Linearly Polarized IR Spectroscopy: Theory and Applications for Structural Analysis" demonstrates how the technique can be properly utilized to obtain important information about the structure and spectral properties of oriented compounds. The book starts with the theoretical basis of linear-dichroic infrared (IR-LD) spectroscop

  6. Identification of the fragment of the 1-methylpyrene cation by mid-IR spectroscopy

    Science.gov (United States)

    Jusko, Pavol; Simon, Aude; Wenzel, Gabi; Brünken, Sandra; Schlemmer, Stephan; Joblin, Christine

    2018-04-01

    The fragment of the 1-methylpyrene cation, 17C 11H+, is expected to exist in two isomeric forms, 1-pyrenemethylium PyrCH2+ and the tropylium containing species PyrC7+. We measured the infrared (IR) action spectrum of cold 17C 11H+ tagged with Ne using a cryogenic ion trap instrument coupled to the FELIX laser. Comparison of the experimental data with density functional theory calculations allows us to identify the PyrCH2+ isomer in our experiments. The IR Multi-Photon Dissociation spectrum was also recorded following the C2H2 loss channel. Its analysis suggests combined effects of anharmonicity and isomerisation while heating the trapped ions, as shown by molecular dynamics simulations.

  7. Modelling a historic oil-tank fire allows an estimation of the sensitivity of the infrared receptors in pyrophilous Melanophila beetles.

    Directory of Open Access Journals (Sweden)

    Helmut Schmitz

    Full Text Available Pyrophilous jewel beetles of the genus Melanophila approach forest fires and there is considerable evidence that these beetles can detect fires from great distances of more than 60 km. Because Melanophila beetles are equipped with infrared receptors and are also attracted by hot surfaces it can be concluded that these infrared receptors are used for fire detection.The sensitivity of the IR receptors is still unknown. The lowest threshold published so far is 0.6 W/m(2 which, however, cannot explain the detection of forest fires by IR radiation from distances larger than approximately 10 km. To investigate the possible sensitivity of the IR receptors we assumed that beetles use IR radiation for remote fire detection and we made use of a historic report about a big oil-tank fire in Coalinga, California, in 1924. IR emission of an oil-tank fire can be calculated by "pool fire" simulations which now are used for fire safety and risk analysis. Assuming that beetles were lured to the fire from the nearest forests 25 and 130 km away, our results show that detection from a distance of 25 km requires a threshold of the IR receptors of at least 3×10(-2 W/m(2. According to our investigations most beetles became aware of the fire from a distance of 130 km. In this case the threshold has to be 1.3×10(-4 W/m(2. Because such low IR intensities are buried in thermal noise we suggest that the infrared sensory system of Melanophila beetles utilizes stochastic resonance for the detection of weak IR radiation. Our simulations also suggest that the biological IR receptors might be even more sensitive than uncooled technical IR sensors. Thus a closer look into the mode of operation of the Melanophila IR receptors seems promising for the development of novel IR sensors.

  8. Rutile IrO2/TiO2 superlattices: A hyperconnected analog to the Ruddelsden-Popper structure

    Science.gov (United States)

    Kawasaki, Jason K.; Baek, David; Paik, Hanjong; Nair, Hari P.; Kourkoutis, Lena F.; Schlom, Darrell G.; Shen, Kyle M.

    2018-05-01

    Dimensionality and connectivity among octahedra play important roles in determining the properties, electronic structure, and phase transitions of transition-metal oxides. Here we demonstrate the epitaxial growth of (110)-oriented alternating layers of IrO2 and TiO2, both of which have the rutile structure. These (IrO2)n/(TiO2)2 superlattices consist of IrO6 and TiO6 octahedra tiled in a hyperconnected, edge- and corner-sharing network. Despite the large lattice mismatch between constituent layers (Δ d∥=-2.1 % and Δ c =+6.6 % ), our reactive molecular-beam epitaxy-grown superlattices show high structural quality as determined by x-ray diffraction and sharp interfaces as observed by transmission electron microscopy. The large strain at the interface is accommodated by an ordered interfacial reconstruction. The superlattices show persistent metallicity down to n =3 atomic layers, and angle-resolved photoemission spectroscopy measurements reveal quantized sub-bands with signatures of IrO2-IrO2 interlayer coupling.

  9. Fleet Protection Using a Small UAV Based IR Sensor

    National Research Council Canada - National Science Library

    Buss, James R; Ax, Jr, George R

    2005-01-01

    A study was performed to define candidate electro-optical and infrared (EO/IR) sensor configurations and assess their potential utility as small UAV-based sensors surveilling a perimeter around surface fleet assets...

  10. A far-infrared spectroscopic survey of intermediate redshift (ultra) luminous infrared galaxies

    International Nuclear Information System (INIS)

    Magdis, Georgios E.; Rigopoulou, D.; Hopwood, R.; Clements, D.; Huang, J.-S.; Farrah, D.; Pearson, C.; Alonso-Herrero, Almudena; Bock, J. J.; Cooray, A.; Griffin, M. J.; Oliver, S.; Perez Fournon, I.; Riechers, D.; Swinyard, B. M.; Thatte, N.; Scott, D.; Valtchanov, I.; Vaccari, M.

    2014-01-01

    We present Herschel far-IR photometry and spectroscopy as well as ground-based CO observations of an intermediate redshift (0.21 ≤ z ≤ 0.88) sample of Herschel-selected (ultra)-luminous infrared galaxies (L IR > 10 11.5 L ☉ ). With these measurements, we trace the dust continuum, far-IR atomic line emission, in particular [C II] 157.7 μm, as well as the molecular gas of z ∼ 0.3 luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) and perform a detailed investigation of the interstellar medium of the population. We find that the majority of Herschel-selected intermediate redshift (U)LIRGs have L C II /L FIR ratios that are a factor of about 10 higher than that of local ULIRGs and comparable to that of local normal and high-z star-forming galaxies. Using our sample to bridge local and high-z [C II] observations, we find that the majority of galaxies at all redshifts and all luminosities follow an L C II –L FIR relation with a slope of unity, from which local ULIRGs and high- z active-galactic-nucleus-dominated sources are clear outliers. We also confirm that the strong anti-correlation between the L C II /L FIR ratio and the far-IR color L 60 /L 100 observed in the local universe holds over a broad range of redshifts and luminosities, in the sense that warmer sources exhibit lower L C II /L FIR at any epoch. Intermediate redshift ULIRGs are also characterized by large molecular gas reservoirs and by lower star formation efficiencies compared to that of local ULIRGs. The high L C II /L FIR ratios, the moderate star formation efficiencies (L IR /L CO ′ or L IR /M H 2 ), and the relatively low dust temperatures of our sample (which are also common characteristics of high-z star-forming galaxies with ULIRG-like luminosities) indicate that the evolution of the physical properties of (U)LIRGs between the present day and z > 1 is already significant by z ∼ 0.3.

  11. Red-IR stimulated luminescence in K-feldspar: Single or multiple trap origin?

    DEFF Research Database (Denmark)

    Andersen, Martin Thalbitzer; Jain, Mayank; Tidemand-Lichtenberg, Peter

    2012-01-01

    We investigate on the origins of the infra-red stimulated luminescence (IRSL) signals in 3 potassium feldspars based on IR-red spectroscopy (700–1050 nm) using a fiber-coupled tunable Ti:Sapphire laser, in combination with different thermal and optical (pre)treatments of the samples. We also...

  12. The WIRED Survey. 2; Infrared Excesses in the SDSS DR7 White Dwarf Catalog

    Science.gov (United States)

    Debes, John H.; Hoard, D. W.; Wachter, Stefanie; Leisawitz, David T.; Cohen, Martin

    2011-01-01

    With the launch of the Wide-field Infrar.ed Survey Explorer (WISE), a new era of detecting planetary debris and brown dwarfs (BDs) around white dwarfs (WDs) has begun with the WISE InfraRed Excesses around Degenerates (WIRED) Survey. The WIRED Survey is sensitive to substellar objects and dusty debris around WDs out to distances exceeding 100 pc, well beyond the completeness level of local WDs. In this paper, we present a cross-correlation of the preliminary Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) WD catalog between the WISE, Two-Micron All Sky Survey (2MASS), UKIRT Infrared Deep Sky Survey (UKIDSS), and SDSS DR7 photometric catalogs. From -18,000 input targets, there are WISE detections comprising 344 "naked" WDs (detection of the WD photosphere only), 1020 candidate WD+M dwarf binaries, 42 candidate WD+BD systems, 52 candidate WD+dust disk systems, and 69 targets with indeterminate infrared excess. We classified all of the detected targets through spectral energy distribution model fitting of the merged optical, near-IR, and WISE photometry. Some of these detections could be the result of contaminating sources within the large (approx. 6") WISE point-spread function; we make a preliminary estimate for the rates of contamination for our WD+BD and WD+disk candidates and provide notes for each target of interest. Each candidate presented here should be confirmed with higher angular resolution infrared imaging or infrared spectroscopy. We also present an overview of the observational characteristics of the detected WDs in the WISE photometric bands, including the relative frequencies of candidate WD+M, WD+BD, and WD+disk systems.

  13. Infra-red process for colour fixation on fabrics

    International Nuclear Information System (INIS)

    Raymond, D.J.; Biau, D.

    1983-01-01

    Infra-red radiations find wide application in industrial processes as heating, drying, stoving and forming. The results are often far better than those from the other techniques: convection oven, gas IR etc ... They come from the electric IR specific advantages: energy direct transmission, emitter and product spectral coupling, possible selectivity. That is the case in the Textile Industry, where experiments showed that infra-red process heating could be efficient for colour fixation on fabrics. Shorter production cycles and energy saving are the main results

  14. Electronic Structures of Reduced and Superreduced Ir2(1,8-diisocyanomenthane)4 n+ Complexes

    Czech Academy of Sciences Publication Activity Database

    Záliš, Stanislav; Hunter, B. M.; Gray, H. B.; Vlček, Antonín

    2017-01-01

    Roč. 56, č. 5 (2017), s. 2874-2883 ISSN 0020-1669 R&D Projects: GA MŠk LD14129 Grant - others:COST(XE) CM1405; COST(XE) CM1202 Institutional support: RVO:61388955 Keywords : electronic structure * electrochemistry * Ir2(1,8-diisocyanomenthane)4 n+ Complexes Subject RIV: CG - Electrochemistry OBOR OECD: Physical chemistry Impact factor: 4.857, year: 2016

  15. Recent Advances in IR and UV/VIS Spectroscopic Characterization of the C76 and C84 Isomers of D2 Symmetry

    Directory of Open Access Journals (Sweden)

    Tamara Jovanović

    2014-01-01

    Full Text Available The stable isomers of the higher fullerenes C76 and C84 with D2 symmetry as well as the basic fullerenes C60 and C70 were isolated from carbon soot and characterized by the new and advanced methods, techniques, and processes. The validity of several semiempirical, ab initio, and DFT theoretical calculations in predicting the general pattern of IR absorption and the vibrational frequencies, as well as the molecular electronic structure of the C76 and C84 isomers of D2 symmetry, is confirmed, based on recent experimental results. An excellent correlation was found between the previously reported theoretical data and the recently obtained experimental results for these molecules over the relevant spectral range for the identification of fullerenes. These results indicate that there are no errors in the calculations in the significant spectral regions, the assumptions that were based on previous comparisons with partial experimental results. Isolated fullerenes are important for their applications in electronic and optical devices, solar cells, optical limiting, sensors, polymers, nanophotonic materials, diagnostic and therapeutic agents, health and environment protection, and so forth.

  16. Quantum mechanical, spectroscopic studies (FT-IR, FT-Raman, NMR, UV) and normal coordinates analysis on 3-([2-(diaminomethyleneamino) thiazol-4-yl] methylthio)-N'-sulfamoylpropanimidamide

    Science.gov (United States)

    Muthu, S.; Uma Maheswari, J.; Sundius, Tom

    2013-05-01

    Famotidine (3-([2-(diaminomethyleneamino) thiazol-4-yl] methylthio)-N'-sulfamoylpropanimidamide) is a histamine H2-receptor antagonist that inhibits stomach acid production, and it is commonly used in the treatment of peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD/GORD). Quantum chemical calculations of the equilibrium geometry of famotidine in the ground state were carried out using density functional theory (DFT/B3LYP) with the 6-311G(d,p) basis set. In addition, harmonic vibrational frequencies, infrared intensities and Raman activities were calculated at the same level of theory. A detailed interpretation of the infrared and Raman spectrum of the drug is also reported. Theoretical simulations of the FT-IR, and FT-Raman spectra of the title compound have been calculated. Good correlations between the experimental 1H and 13C NMR chemical shifts and calculated GIAO shielding tensors were found. The results of the energy and oscillator strength calculations by time-dependent density functional theory (TD-DFT) supplement the experimental findings. Total and partial density of state (TDOS and PDOS) and also overlap population density of state (COOP or OPDOS) diagrams analysis were presented. The dipole moment, linear polarizability and first order hyperpolarizability values were also computed. The linear polarizability and first order hyperpolarizabilities of the studied molecule indicate that the compound is a good candidate for nonlinear optical materials.

  17. Low cost, patterning of human hNT brain cells on parylene-C with UV & IR laser machining.

    Science.gov (United States)

    Raos, Brad J; Unsworth, C P; Costa, J L; Rohde, C A; Doyle, C S; Delivopoulos, E; Murray, A F; Dickinson, M E; Simpson, M C; Graham, E S; Bunting, A S

    2013-01-01

    This paper describes the use of 800nm femtosecond infrared (IR) and 248nm nanosecond ultraviolet (UV) laser radiation in performing ablative micromachining of parylene-C on SiO2 substrates for the patterning of human hNT astrocytes. Results are presented that support the validity of using IR laser ablative micromachining for patterning human hNT astrocytes cells while UV laser radiation produces photo-oxidation of the parylene-C and destroys cell patterning. The findings demonstrate how IR laser ablative micromachining of parylene-C on SiO2 substrates can offer a low cost, accessible alternative for rapid prototyping, high yield cell patterning.

  18. Highly accurate potential energy surface, dipole moment surface, rovibrational energy levels, and infrared line list for {sup 32}S{sup 16}O{sub 2} up to 8000 cm{sup −1}

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xinchuan, E-mail: Xinchuan.Huang-1@nasa.gov, E-mail: Timothy.J.Lee@nasa.gov [SETI Institute, 189 Bernardo Ave, Suite No. 100, Mountain View, California 94043 (United States); Schwenke, David W., E-mail: David.W.Schwenke@nasa.gov [MS T27B-1, NAS Facility, NASA Ames Research Center, Moffett Field, California 94035 (United States); Lee, Timothy J., E-mail: Xinchuan.Huang-1@nasa.gov, E-mail: Timothy.J.Lee@nasa.gov [MS 245-1, Space Science and Astrobiology Division, NASA Ames Research Center, Moffett Field, California 94035 (United States)

    2014-03-21

    A purely ab initio potential energy surface (PES) was refined with selected {sup 32}S{sup 16}O{sub 2} HITRAN data. Compared to HITRAN, the root-mean-squares error (σ{sub RMS}) for all J = 0–80 rovibrational energy levels computed on the refined PES (denoted Ames-1) is 0.013 cm{sup −1}. Combined with a CCSD(T)/aug-cc-pV(Q+d)Z dipole moment surface (DMS), an infrared (IR) line list (denoted Ames-296K) has been computed at 296 K and covers up to 8000 cm{sup −1}. Compared to the HITRAN and CDMS databases, the intensity agreement for most vibrational bands is better than 85%–90%. Our predictions for {sup 34}S{sup 16}O{sub 2} band origins, higher energy {sup 32}S{sup 16}O{sub 2} band origins and missing {sup 32}S{sup 16}O{sub 2} IR bands have been verified by most recent experiments and available HITRAN data. We conclude that the Ames-1 PES is able to predict {sup 32/34}S{sup 16}O{sub 2} band origins below 5500 cm{sup −1} with 0.01–0.03 cm{sup −1} uncertainties, and the Ames-296K line list provides continuous, reliable and accurate IR simulations. The K{sub a}-dependence of both line position and line intensity errors is discussed. The line list will greatly facilitate SO{sub 2} IR spectral experimental analysis, as well as elimination of SO{sub 2} lines in high-resolution astronomical observations.

  19. Identification of forged Bank of England £20 banknotes using IR spectroscopy.

    Science.gov (United States)

    Sonnex, Emily; Almond, Matthew J; Baum, John V; Bond, John W

    2014-01-24

    Bank of England notes of £20 denomination have been studied using infrared spectroscopy in order to generate a method to identify forged notes. An aim of this work was to develop a non-destructive method so that a small, compact Fourier transform infrared spectrometer (FT-IR) instrument could be used by bank workers, police departments or others such as shop assistants to identify forged notes in a non-lab setting. The ease of use of the instrument is the key to this method, as well as the relatively low cost. The presence of a peak at 1400 cm(-1) arising from νasym (CO3(2-)) from the blank paper section of a forged note proved to be a successful indicator of the note's illegality for the notes that we studied. Moreover, differences between the spectra of forged and genuine £20 notes were observed in the ν(OH) (ca. 3500 cm(-1)), ν(C-H) (ca. 2900 cm(-1)) and ν(C=O) (ca. 1750 cm(-1)) regions of the IR spectrum recorded for the polymer film covering the holographic strip. In cases where these simple tests fail, we have shown how an infrared microscope can be used to further differentiate genuine and forged banknotes by producing infrared maps of selected areas of the note contrasting inks with background paper. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Ammonia IR Absorbance Measurements with an Equilibrium Vapor Cell

    National Research Council Canada - National Science Library

    Field, Paul

    2004-01-01

    Infrared (IR) absorbance spectra were acquired for 18 ammonia vapor pressures. The vapor pressures were generated with 15 gravimetrically prepared aqueous solutions and three commercial aqueous solutions using a dynamic method I.E...

  1. Infrared photonic bandgap materials and structures

    Science.gov (United States)

    Sundaram, S. K.; Keller, P. E.; Riley, B. J.; Martinez, J. E.; Johnson, B. R.; Allen, P. J.; Saraf, L. V.; Anheier, N. C., Jr.; Liau, F.

    2006-02-01

    Three-dimensional periodic dielectric structure can be described by band theory, analogous to electron waves in a crystal. Photonic band gap (PBG) structures were introduced in 1987. The PBG is an energy band in which optical modes, spontaneous emission, and zero-point fluctuations are all absent. It was first theoretically predicted that a three-dimensional photonic crystal could have a complete band gap. E. Yablonovitch built the first three-dimensional photonic crystal (Yablonovite) on microwave length scale, with a complete PBG. In nature, photonic crystals occur as semiprecious opal and the microscopic structures on the wings of some tropical butterflies, which are repeating structures (PBG structure/materials) that inhibit the propagation of some frequencies of light. Pacific Northwest National Laboratory (PNNL) has been developing tunable (between 3.5 and 16 μm) quantum cascade lasers (QCL), chalcogenides, and all other components for an integrated approach to chemical sensing. We have made significant progress in modeling and fabrication of infrared photonic band gap (PBG) materials and structures. We modeled several 2-D designs and defect configurations. Transmission spectra were computed by the Finite Difference Time Domain Method (with FullWAVE TM). The band gaps were computed by the Plane Wave Expansion Method (with BandSOLVE TM). The modeled designs and defects were compared and the best design was identified. On the experimental front, chalcogenide glasses were used as the starting materials. As IIS 3, a common chalcogenide, is an important infrared (IR) transparent material with a variety of potential applications such as IR sensors, waveguides, and photonic crystals. Wet-chemical lithography has been extended to PBG fabrication and challenges identified. An overview of results and challenges will be presented.

  2. Discussion of isomeric ratios in (p, n) and (d, 2n) reaction

    Energy Technology Data Exchange (ETDEWEB)

    Bakhshiyan, T. M., E-mail: tiruhi44@mail.ru [Yerevan State University (Armenia)

    2016-01-15

    Isomeric ratios (IR) in the (p, n) and (d, 2n) reactions are considered. The dependence of IR values on the projectile type and energy, the target- and product-nucleus spin, the spin difference between the isomeric and ground states of products, and the product mass number is discussed. The isomeric ratios for 46 product nuclei (from {sup 44m,g}Sc to {sup 127m,g}Xe) obtained in reactions where target and product nuclei have identical mass numbers were calculated at energies from the reaction threshold to 50 MeV (with a step of ΔE = 1 MeV). The calculations in question were performed with the aid of the TALYS 1.4 code package. The calculated IR values were compared with their experimental counterparts available from the literature (EXFOR database). In the majority of cases, the calculated IR values agree well with the experimental data in question. It is noteworthy that the IR values obtained in (d, 2n) reactions are substantially greater than those in (p, n) reactions.

  3. Infrared problems in QCD and related topics

    International Nuclear Information System (INIS)

    Doria, R.M.

    1981-08-01

    This thesis is based in six works. The first is presented in the Introduction in order to justify the philosophical part of the above title and to develop a concept of Reality. In Chapter 1 the presence of Infrared Divergence in QCD is discovered. It is studied in the reaction q + q → #betta#* + q + q + soft gluons, where q is the quark, #betta#* is a virtual photon. The quarks are taken each to be colour (and spin) averaged. This gives a cancellation of the leading IR divergences. The uncancelled IR divergences change the Born cross section and dimensional IR regularisation with d = 4 + eta is used. The original work had errors which produced a cancellation in such a way that did not alter the final answer. At high energies this result is proportional to (1-#betta#) ln (1-#betta#). This means that at #betta# → 1 this IR divergence effect is expected to disappear. In Chapter two, the same reaction is studied but with a gluon instead of a quark. Collinear divergence also appears. Chapter 3 is about the solution of one-loop integrals using hypergeometric functions. The solutions obtained are exact. Chapter 4 criticizes the way to predict the nature of the divergence through the Power Counting Method (NPC). (author)

  4. Facile And Reversible Co Insertion Into The Ir-ch3 Bond Of [ir4(ch3)(co)8(μ4- η3-ph2pccph)(μ-pph2)

    OpenAIRE

    Vargas M.D.; Pereira R.M.S.; Braga D.; Grepioni F.

    1993-01-01

    Reaction of [Ir4H(CO)10(mu-PPh2)) with BuLi, Ph2PC=CPh and then Mel gives [Ir4(CH3)(CO)8(mu4-eta3-Ph2PCCPh)(mu-PPh2)], which undergoes a reversible two-step CO insertion under extremely mild conditions to yield Ir4{(CH3C(O)}(CO)8-(mu4:eta3-Ph2PCCPh)(mu-PPh2)] as the final product; the structures of both species have been established by X-ray diffraction studies.

  5. Yo-Yo IR2 testing of elite and sub-elite soccer players

    DEFF Research Database (Denmark)

    Ingebrigtsen, Jørgen; Bendiksen, Mads; Randers, Morten Bredsgaard

    2012-01-01

    Abstract We examined performance, heart rate response and construct validity of the Yo-Yo IR2 test by testing 111 elite and 92 sub-elite soccer players from Norway and Denmark. VO(2)max, Yo-Yo IR1 and repeated sprint tests (RSA) (n = 51) and match-analyses (n = 39) were also performed. Yo-Yo IR2...

  6. Isotope effects of reactions in quantum solids initiated by IR + UV lasers: quantum model simulations for Cl((2)P(3/2)) + X(2)(ν) → XCl + X in X(2) matrices (X = H, D).

    Science.gov (United States)

    Korolkov, M V; Manz, J; Schild, A

    2010-09-16

    Six isotope effects (i)-(vi) are discovered for the reactions Cl + H(2)(ν) → HCl + H in solid para-H(2) ( 1 ) versus Cl + D(2)(ν) → DCl + D in ortho-D(2) ( 2 ), by means of quantum reaction dynamics simulations, within the frame of our simple model ( J. Phys. Chem. A 2009 , 113 , 7630 . ). Experimentally, the reactions may be initiated for ν = 0 and ν ≥ 1, by means of "UV only" photodissociation of the matrix-isolated precursor, Cl(2), or by "IR + UV" coirradiation ( Kettwich , S. C. , Raston , P. L. , and Anderson , D. T. J. Phys. Chem. A 2009 , 113 , 7621 . ), respectively. Specifically, (i) various shape and Feshbach reaction resonances correlate with vibrational thresholds of reactants and products, due to the near-thermoneutrality and low barrier of the system. The energetic density of resonances increases as the square root of mass, from M(X) = M(H) to M(D). (ii) The state selective reaction ( 1 ), ν = 1, is supported by a shape resonance, whereas this type of resonance is absent in ( 2 ), ν = 1. As a consequence, time-resolved measurements should monitor different three-step versus direct error-function type evolutions of the formation of the products. (iii) The effective barrier is lower for reaction 1 , ν = 0, enhancing the tunneling rate, as compared to that for reaction 2 , ν = 0. (iv) For reference, the reaction probabilities P versus total energy E(tot) in the gas exhibit sharp resonance peaks or zigzag behaviors of the reaction probability P versus total energy, near the levels of resonances ( Persky , A. and Baer , M. J. Chem. Phys . 1974 , 60 , 133 . ). These features tend to be washed out and broadened for reaction 1 , and even more so for reaction 2 . For comparison, they disappear for reactions in classical solids. (v) The slopes of P versus E(tot) below the potential barrier increase more steeply for reaction 1 , ν = 0, than for reaction 2 , ν = 0. This enhances the tunneling rate of the heavier isotopomer, reaction 2 , ν = 0

  7. New intelligent multifunctional SiO2/VO2 composite films with enhanced infrared light regulation performance, solar modulation capability, and superhydrophobicity.

    Science.gov (United States)

    Wang, Chao; Zhao, Li; Liang, Zihui; Dong, Binghai; Wan, Li; Wang, Shimin

    2017-01-01

    Highly transparent, energy-saving, and superhydrophobic nanostructured SiO 2 /VO 2 composite films have been fabricated using a sol-gel method. These composite films are composed of an underlying infrared (IR)-regulating VO 2 layer and a top protective layer that consists of SiO 2 nanoparticles. Experimental results showed that the composite structure could enhance the IR light regulation performance, solar modulation capability, and hydrophobicity of the pristine VO 2 layer. The transmittance of the composite films in visible region ( T lum ) was higher than 60%, which was sufficient to meet the requirements of glass lighting. Compared with pristine VO 2 films and tungsten-doped VO 2 film, the near IR control capability of the composite films was enhanced by 13.9% and 22.1%, respectively, whereas their solar modulation capability was enhanced by 10.9% and 22.9%, respectively. The water contact angles of the SiO 2 /VO 2 composite films were over 150°, indicating superhydrophobicity. The transparent superhydrophobic surface exhibited a high stability toward illumination as all the films retained their initial superhydrophobicity even after exposure to 365 nm light with an intensity of 160 mW . cm -2 for 10 h. In addition, the films possessed anti-oxidation and anti-acid properties. These characteristics are highly advantageous for intelligent windows or solar cell applications, given that they can provide surfaces with anti-fogging, rainproofing, and self-cleaning effects. Our technique offers a simple and low-cost solution to the development of stable and visible light transparent superhydrophobic surfaces for industrial applications.

  8. Fourier-transform infrared spectroscopic studies of dithia ...

    Indian Academy of Sciences (India)

    We present here infrared absorption spectra of dithia tetraphenylporphine and its cation in the 450-1600 and 2900-3400 cm-1 regions. Most of the allowed IR bands are observed in pairs due to overall 2ℎ point group symmetry of the molecule. The observed bands have been assigned to the porphyrin skeleton and phenyl ...

  9. Affordable, Accessible, Immediate: Capture Stunning Images with Digital Infrared Photography

    Science.gov (United States)

    Snyder, Mark

    2011-01-01

    Technology educators who teach digital photography should consider incorporating an infrared (IR) photography component into their program. This is an area where digital photography offers significant benefits. Either type of IR imaging is very interesting to explore, but traditional film-based IR photography is difficult and expensive. In…

  10. Characterization and identification of microorganisms by FT-IR microspectrometry

    Science.gov (United States)

    Ngo-Thi, N. A.; Kirschner, C.; Naumann, D.

    2003-12-01

    We report on a novel FT-IR approach for microbial characterization/identification based on a light microscope coupled to an infrared spectrometer which offers the possibility to acquire IR-spectra of microcolonies containing only few hundred cells. Microcolony samples suitable for FT-IR microspectroscopic measurements were obtained by a replica technique with a stamping device that transfers spatially accurate cells of microcolonies growing on solid culture plates to a special, IR-transparent or reflecting stamping plate. High quality spectra could be recorded either by applying the transmission/absorbance or the reflectance/absorbance mode of the infrared microscope. Signal to noise ratios higher than 1000 were obtained for microcolonies as small as 40 μm in diameter. Reproducibility levels were established that allowed species and strain identification. The differentiation and classification capacity of the FT-IR microscopic technique was tested for different selected microorganisms. Cluster and factor analysis methods were used to evaluate the complex spectral data. Excellent discrimination between bacteria and yeasts, and at the same time Gram-negative and Gram-positive bacterial strains was obtained. Twenty-two selected strains of different species within the genus Staphylococcus were repetitively measured and could be grouped into correct species cluster. Moreover, the results indicated that the method allows also identifications at the subspecies level. Additionally, the new approach allowed spectral mapping analysis of single colonies which provided spatially resolved characterization of growth heterogeneity within complex microbial populations such as colonies.

  11. MTG infrared sounder detection chain: first radiometric test results

    Science.gov (United States)

    Dumestier, D.; Pistone, F.; Dartois, T.; Blazquez, E.

    2017-11-01

    Europe's next fleet of geostationary meteorological satellites, MeteoSat Third Generation, will introduce new functions in addition to continuity of high-resolution meteorological data. The atmosphere Infrared Sounder (IRS), as high -end instrument, is part of this challenging program. IRS principle is a Fourier Transform Interferometer, which allows recomposing atmospheric spectrum after infrared photons detection. Transmission spectrums will be used to support numerical weather prediction. IRS instrument is able to offer full disk coverage in one hour, an on-ground resolution of 4 by 4 km, in two spectral bands (MWIR: 1600 to 2175cm-1 and LWIR: 700 to 1210cm-1) with a spectral resolution of 0.6cm-1. Among critical technologies and processes, IRS detection chain shall offer outstanding characteristics in terms of radiometric performance like Signal to Noise Ratio (SNR), dynamic range and linearity. Selected detectors are HgCdTe two-dimensions arrays, cooled at 55 Kelvins, hybridized on snapshot silicon read-out circuit at 160x160 format. Video electronics present 16 bits resolution, and the whole detection chain (Detectors and electronics) permits to reach SNR between 2 000 and 10 000 as requested by the application. Radiometric onground test results performed on design representative detection chains are presented and are confirming the challenging phase A design choices.

  12. Simultaneous particle image velocimetry and infrared imagery of microscale breaking waves

    International Nuclear Information System (INIS)

    Siddiqui, M.H. Kamran; Loewen, Mark R.; Richardson, Christine; Asher, William E.; Jessup, Andrew T.

    2001-01-01

    We report the results from a laboratory investigation in which microscale breaking waves were detected using an infrared (IR) imager and two-dimensional (2-D) velocity fields were simultaneously measured using particle image velocimetry (PIV). In addition, the local heat transfer velocity was measured using the controlled flux technique. To the best of our knowledge these are the first measurements of the instantaneous 2-D velocity fields generated beneath microscale breaking waves. Careful measurements of the water surface profile enabled us to make accurate estimates of the near-surface velocities using PIV. Previous experiments have shown that behind the leading edge of a microscale breaker the cool skin layer is disrupted creating a thermal signature in the IR image [Jessup et al., J. Geophys. Res. 102, 23145 (1997)]. The simultaneously sampled IR images and PIV data enabled us to show that these disruptions or wakes are typically produced by a series of vortices that form behind the leading edge of the breaker. When the vortices are first formed they are very strong and coherent but as time passes, and they move from the crest region to the back face of the wave, they become weaker and less coherent. The near-surface vorticity was correlated with both the fractional area coverage of microscale breaking waves and the local heat transfer velocity. The strong correlations provide convincing evidence that the wakes produced by microscale breaking waves are regions of high near-surface vorticity that are in turn responsible for enhancing air-water heat transfer rates

  13. Superconductivity and magnetism in Ir-doped GdFeAsO

    International Nuclear Information System (INIS)

    Cui, Y.J.; Chen, Y.L.; Cheng, C.H.; Yang, Y.; Jiang, J.; Wang, Y.Z.; Zhang, Y.; Zhao, Y.

    2010-01-01

    The 5d-transition metal, Ir has successfully been doped at Fe site and induced superconductivity in GdFeAsO at T c = 18.9 K and ∼20 atom%. The Ir-doping shortened the c-axis length and stretched the a-axis one, which led to enhance the coupling between the FeAs- and SmO-layer, and to weaken the bonding between Fe and As atom. Paramagnetism was observed in all of the samples, which was resulted from the magnetic Gd ion as in the F-doped GdFeAsO. An upper critical field of GdFe 0.8 Ir 0.2 AsO was extrapolated to around 24 T, much smaller than that of F-doped GdFeAsO owing to a relatively low T c and small value of dH c2 /dT.

  14. Premier's imaging IR limb sounder

    Science.gov (United States)

    Kraft, Stefan; Bézy, Jean-Loup; Meynart, Roland; Langen, Jörg; Carnicero Dominguez, Bernardo; Bensi, Paolo; Silvestrin, Pierluigi

    2017-11-01

    The Imaging IR Limb Sounder (IRLS) is one of the two instruments planned on board of the candidate Earth Explorer Core Mission PREMIER. PREMIER stands for PRocess Exploration through Measurements of Infrared and Millimetre-wave Emitted Radiation. PREMIER went recently through the process of a feasibility study (Phase A) within the Earth Observation Envelope Program. Emerging from recent advanced instrument technologies IRLS shall, next to a millimetre-wave limb sounder (called STEAMR), explore the benefits of three-dimensional limb sounding with embedded cloud imaging capability. Such 3D imaging technology is expected to open a new era of limb sounding that will allow detailed studies of the link between atmospheric composition and climate, since it will map simultaneously fields of temperature and many trace gases in the mid/upper troposphere and stratosphere across a large vertical and horizontal field of view and with high vertical and horizontal resolution. PREMIER shall fly in a tandem formation looking backwards to METOP's swath and thereby improve meteorological and environmental analyses.

  15. Obstacle-avoiding robot with IR and PIR motion sensors

    Science.gov (United States)

    Ismail, R.; Omar, Z.; Suaibun, S.

    2016-10-01

    Obstacle avoiding robot was designed, constructed and programmed which may be potentially used for educational and research purposes. The developed robot will move in a particular direction once the infrared (IR) and the PIR passive infrared (PIR) sensors sense a signal while avoiding the obstacles in its path. The robot can also perform desired tasks in unstructured environments without continuous human guidance. The hardware was integrated in one application board as embedded system design. The software was developed using C++ and compiled by Arduino IDE 1.6.5. The main objective of this project is to provide simple guidelines to the polytechnic students and beginners who are interested in this type of research. It is hoped that this robot could benefit students who wish to carry out research on IR and PIR sensors.

  16. HerMES: THE FAR-INFRARED EMISSION FROM DUST-OBSCURED GALAXIES

    International Nuclear Information System (INIS)

    Calanog, J. A.; Wardlow, J.; Fu, Hai; Cooray, A.; Assef, R. J.; Bock, J.; Riechers, D.; Schulz, B.; Casey, C. M.; Conley, A.; Farrah, D.; Oliver, S. J.; Roseboom, I. G.; Ibar, E.; Kartaltepe, J.; Magdis, G.; Rigopoulou, D.; Marchetti, L.; Pérez-Fournon, I.; Scott, Douglas

    2013-01-01

    Dust-obscured galaxies (DOGs) are an ultraviolet-faint, infrared-bright galaxy population that reside at z ∼ 2 and are believed to be in a phase of dusty star-forming and active galactic nucleus (AGN) activity. We present far-infrared (far-IR) observations of a complete sample of DOGs in the 2 deg 2 of the Cosmic Evolution Survey. The 3077 DOGs have (z) = 1.9 ± 0.3 and are selected from 24 μm and r + observations using a color cut of r + – [24] ≥ 7.5 (AB mag) and S 24 ≥ 100 μJy. Based on the near-IR spectral energy distributions, 47% are bump DOGs (star formation dominated) and 10% are power-law DOGs (AGN-dominated). We use SPIRE far-IR photometry from the Herschel Multi-tiered Extragalactic Survey to calculate the IR luminosity and characteristic dust temperature for the 1572 (51%) DOGs that are detected at 250 μm (≥3σ). For the remaining 1505 (49%) that are undetected, we perform a median stacking analysis to probe fainter luminosities. Herschel-detected and undetected DOGs have average luminosities of (2.8 ± 0.4) × 10 12 L ☉ and (0.77 ± 0.08) × 10 12 L ☉ , and dust temperatures of (33 ± 7) K and (37 ± 5) K, respectively. The IR luminosity function for DOGs with S 24 ≥ 100 μJy is calculated, using far-IR observations and stacking. DOGs contribute 10%-30% to the total star formation rate (SFR) density of the universe at z = 1.5-2.5, dominated by 250 μm detected and bump DOGs. For comparison, DOGs contribute 30% to the SFR density for all z = 1.5-2.5 galaxies with S 24 ≥ 100 μJy. DOGs have a large scatter about the star formation main sequence and their specific SFRs show that the observed phase of star formation could be responsible for their total observed stellar mass at z ∼ 2

  17. HerMES: THE FAR-INFRARED EMISSION FROM DUST-OBSCURED GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Calanog, J. A.; Wardlow, J.; Fu, Hai; Cooray, A. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Assef, R. J. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Bock, J.; Riechers, D.; Schulz, B. [California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125 (United States); Casey, C. M. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Conley, A. [Center for Astrophysics and Space Astronomy 389-UCB, University of Colorado, Boulder, CO 80309 (United States); Farrah, D.; Oliver, S. J.; Roseboom, I. G. [Astronomy Centre, Department of Physics and Astronomy, University of Sussex, Brighton BN1 9QH (United Kingdom); Ibar, E. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Kartaltepe, J. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Magdis, G.; Rigopoulou, D. [Department of Astrophysics, Denys Wilkinson Building, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Marchetti, L. [Department of Physical Sciences, The Open University, Milton Keynes MK7 6AA (United Kingdom); Pérez-Fournon, I. [Instituto de Astrofísica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Scott, Douglas [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); and others

    2013-09-20

    Dust-obscured galaxies (DOGs) are an ultraviolet-faint, infrared-bright galaxy population that reside at z ∼ 2 and are believed to be in a phase of dusty star-forming and active galactic nucleus (AGN) activity. We present far-infrared (far-IR) observations of a complete sample of DOGs in the 2 deg{sup 2} of the Cosmic Evolution Survey. The 3077 DOGs have (z) = 1.9 ± 0.3 and are selected from 24 μm and r {sup +} observations using a color cut of r {sup +} – [24] ≥ 7.5 (AB mag) and S{sub 24} ≥ 100 μJy. Based on the near-IR spectral energy distributions, 47% are bump DOGs (star formation dominated) and 10% are power-law DOGs (AGN-dominated). We use SPIRE far-IR photometry from the Herschel Multi-tiered Extragalactic Survey to calculate the IR luminosity and characteristic dust temperature for the 1572 (51%) DOGs that are detected at 250 μm (≥3σ). For the remaining 1505 (49%) that are undetected, we perform a median stacking analysis to probe fainter luminosities. Herschel-detected and undetected DOGs have average luminosities of (2.8 ± 0.4) × 10{sup 12} L{sub ☉} and (0.77 ± 0.08) × 10{sup 12} L{sub ☉}, and dust temperatures of (33 ± 7) K and (37 ± 5) K, respectively. The IR luminosity function for DOGs with S{sub 24} ≥ 100 μJy is calculated, using far-IR observations and stacking. DOGs contribute 10%-30% to the total star formation rate (SFR) density of the universe at z = 1.5-2.5, dominated by 250 μm detected and bump DOGs. For comparison, DOGs contribute 30% to the SFR density for all z = 1.5-2.5 galaxies with S{sub 24} ≥ 100 μJy. DOGs have a large scatter about the star formation main sequence and their specific SFRs show that the observed phase of star formation could be responsible for their total observed stellar mass at z ∼ 2.

  18. Caracterización estructural de vidrios del sistema SiO2- B2O3-Na2O mediante espectroscopías IR y Raman

    Directory of Open Access Journals (Sweden)

    Oteo, J. L.

    2009-10-01

    Full Text Available Infrared and Raman spectroscopies have been used to analyze two series of sodium silicoborate glasses with 10 % and 20 % of Na2O. The obtained results are in accordance with those found in literature when using Raman and Infrared spectroscopies, however here it has been analyze in more detail the Polimerization Index (IP of both systems. It has been observed that IP decreases with B concentration except for low B content glasses. This result has been assigned to an incomplete melting of such glasses due to the high temperatures needed to obtain well-melting glasses. Finally, it has been analyzed the BO4/BO3 ratio as a function of the Na2O concentration, showing that as it would be expected the high BO4 concentration appears when the Na2O concentration is between 0.3 – 0.4 in moles.En este trabajo se han estudiado mediante espectroscopías IR y Raman dos series de vidrios del sistema SiO2-B2O3-Na2O con contenidos fijos del 10 y 20% de Na2O. Los resultados obtenidos en cuanto a la evolución de las bandas IR o Raman son concordantes con los encontrados en la bibliografía, sin embargo en este trabajo se estudian más a fondo dichos resultados sobre todo en relación al índice de polimerización (IP de la estructura vítrea de sílice y su variación para cada sistema. Se ha comprobado cómo el IP disminuye al aumentar el contenido en Boro con la relación B/Si excepto para contenidos en B pequeños lo que en principio podría indicar que estos últimos vidrios no han sido fundidos correctamente y no se ha llegado a una completa homogenización de la mezcla vitrificable. Finalmente se ha analizado la relación BO4/BO3 en función del contenido en Na2O observándose cómo el número de grupos BO4 es mayor cuando el contenido en Na2O está comprendido entre 0.3 y 0.4 molar.

  19. Facile Dehydrogenation of Ethane on the IrO2(110) Surface.

    Science.gov (United States)

    Bian, Yingxue; Kim, Minkyu; Li, Tao; Asthagiri, Aravind; Weaver, Jason F

    2018-02-21

    Realizing the efficient and selective conversion of ethane to ethylene is important for improving the utilization of hydrocarbon resources, yet remains a major challenge in catalysis. Herein, ethane dehydrogenation on the IrO 2 (110) surface is investigated using temperature-programmed reaction spectroscopy (TPRS) and density functional theory (DFT) calculations. The results show that ethane forms strongly bound σ-complexes on IrO 2 (110) and that a large fraction of the complexes undergo C-H bond cleavage during TPRS at temperatures below 200 K. Continued heating causes as much as 40% of the dissociated ethane to dehydrogenate and desorb as ethylene near 350 K, with the remainder oxidizing to CO x species. Both TPRS and DFT show that ethylene desorption is the rate-controlling step in the conversion of ethane to ethylene on IrO 2 (110) during TPRS. Partial hydrogenation of the IrO 2 (110) surface is found to enhance ethylene production from ethane while suppressing oxidation to CO x species. DFT predicts that hydrogenation of reactive oxygen atoms of the IrO 2 (110) surface effectively deactivates these sites as H atom acceptors, and causes ethylene desorption to become favored over further dehydrogenation and oxidation of ethane-derived species. The study reveals that IrO 2 (110) exhibits an exceptional ability to promote ethane dehydrogenation to ethylene near room temperature, and provides molecular-level insights for understanding how surface properties influence selectivity toward ethylene production.

  20. Dust Radiative Transfer Modeling of the Infrared Ring around the Magnetar SGR 1900+14

    Energy Technology Data Exchange (ETDEWEB)

    Natale, G. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Rea, N.; Torres, D. F.; Girart, J. M. [Institute of Space Sciences (IEEC–CSIC), Campus UAB, Carrer de Can Magrans S/N, E-08193 Barcelona (Spain); Lazzati, D. [Department of Physics, Oregon State University, 301 Weniger Hall, Corvallis, OR 97331 (United States); Perna, R., E-mail: gnatale@uclan.ac.uk [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States)

    2017-03-01

    A peculiar infrared ring-like structure was discovered by Spitzer around the strongly magnetized neutron star SGR 1900+14. This infrared (IR) structure was suggested to be due to a dust-free cavity, produced by the Soft Gamma-ray Repeaters (SGRs) Giant Flare occurring in 1998, and kept illuminated by surrounding stars. Using a 3D dust radiative transfer code, we aimed to reproduce the emission morphology and the integrated emission flux of this structure assuming different spatial distributions and densities for the dust, and different positions for the illuminating stars. We found that a dust-free ellipsoidal cavity can reproduce the shape, flux, and spectrum of the ring-like IR emission, provided that the illuminating stars are inside the cavity and that the interstellar medium has high gas density ( n {sub H} ∼ 1000 cm{sup −3}). We further constrain the emitting region to have a sharp inner boundary and to be significantly extended in the radial direction, possibly even just a cavity in a smooth molecular cloud. We discuss possible scenarios for the formation of the dustless cavity and the particular geometry that allows it to be IR-bright.

  1. Size Effect on the Infrared Spectra of Condensed Media under Conditions of 1D, 2D, and 3D Dielectric Confinement

    KAUST Repository

    Shaganov, Igor I.

    2010-10-07

    The effect of dielectric confinement on the peak position of intramolecular and a lattice vibration in the infrared spectra of various condensed media is investigated. Liquid benzene, carbon disulfide, and chloroform, as well as amorphous SiO2 and microcrystalline MgO particles, were characterized in this study. The absorption spectra of organic liquids and aqueous solutions of a silica submicrometer powder were measured under a variety of dielectric confinement configurations using Fourier transform Infrared spectroscopy. A significant shift of the resonant absorption band of liquid mesoparticles has been observed under dielectric confinement, which is in good agreement with model predictions. A corresponding expression for the dielectric loss spectrum of an absorbing composite medium was obtained using a Maxwell-Garnett generalized equation for the cases of one, two, and three-dimensional dielectric confinement in both ordered and disordered thin layers (disks), rods (wires or needles), and spheres of an absorbing medium. The experimental data on peak positions obtained from the infrared spectra of the organic liquids investigated in this work, as well as from the infrared spectra of amorphous quartz spherical particles and rods, are in good agreement with the calculated data. It is shown using simulations of the absorption spectrum of MgO powder that the approach suggested can be applied under certain conditions to the modeling of the spectra of microcrystalline particles of nonspheroidal shape. © 2010 American Chemical Society.

  2. Moving the Plasmon of LaB6 from IR to Near-IR via Eu-Doping

    Directory of Open Access Journals (Sweden)

    Tracy M. Mattox

    2018-02-01

    Full Text Available Lanthanum hexaboride (LaB6 has become a material of intense interest in recent years due to its low work function, thermal stability and intriguing optical properties. LaB6 is also a semiconductor plasmonic material with the ability to support strong plasmon modes. Some of these modes uniquely stretch into the infrared, allowing the material to absorb around 1000 nm, which is of great interest to the window industry. It is well known that the plasmon of LaB6 can be tuned by controlling particle size and shape. In this work, we explore the options available to further tune the optical properties by describing how metal vacancies and Eu doping concentrations are additional knobs for tuning the absorbance from the near-IR to far-IR in La1−xEuxB6 (x = 0, 0.2, 0.5, 0.8, and 1.0. We also report that there is a direct correlation between Eu concentration and metal vacancies within the Eu1−xLaxB6.

  3. Chemical durability and Structural approach of the glass series (40-y) Na2O-yFe2O3-5Al2O3-55P2O5-by IR, X-ray diffraction and Mössbauer Spectroscopy

    International Nuclear Information System (INIS)

    Aqdim, S; Sayouty, El H; Elouad, B; Greneche, J M

    2012-01-01

    The relationship between the composition and structure for the glasses of general composition (40-y)Na 2 O-yFe 2 O 3 -5Al 2 O 3 -55P 2 O 5 (5≤y≤20), has been studied. The chemical durability and density of these glasses increase with increasing Fe 2 O 3 content. The dissolution rate (D R ), calculated from the weight loss in distilled water at 90°C for up to 20 days was ≈ 3.10 −9 g/cm 2 /mn which is 30 times lower than that of window glass. The structure and valence states of the iron ions in the glasses were investigated using, X-ray diffraction, 57Fe Mössbauer spectrometry, potentiometric analysis, and infrared spectroscopy. Both Mössbauer spectrometry and potentiometric analysis allow to estimate both Fe 2+ and Fe 3+ contents in all these glasses. X-ray diffraction indicates that the local structure of iron phosphate glasses is related to the short range structures of NaFeP 2 O 7 . Infrared spectra indicate the formation of P–O–Fe bonds in the pyrophosphate glasses that replace P–O–Na bonds. The presence of a small content of Al 2 O 3 in the glass seems to play a role as a network modifier. The addition of Fe 2 O 3 to Al 2 O 3 in phosphate glasses favours the enhancement of the formation of pyrophosphate units because iron ions have stronger effect on the depolymerization of metaphosphate chains than the aluminium ions. Finally, the I.R spectra indicate that the presence of P-O-Fe bands of these glasses containing more than 15 mol%Fe 2 O 3 is consistent with their good chemical durability.

  4. 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...

  5. Dust-deficient Palomar-Green Quasars and the Diversity of AGN Intrinsic IR Emission

    Energy Technology Data Exchange (ETDEWEB)

    Lyu, Jianwei; Rieke, G. H. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Shi, Yong, E-mail: jianwei@email.arizona.edu [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)

    2017-02-01

    To elucidate the intrinsic broadband infrared (IR) emission properties of active galactic nuclei (AGNs), we analyze the spectral energy distributions (SEDs) of 87 z ≲ 0.5 Palomar-Green (PG) quasars. While the Elvis AGN template with a moderate far-IR correction can reasonably match the SEDs of the AGN components in ∼60% of the sample (and is superior to alternatives such as that by Assef), it fails on two quasar populations: (1) hot-dust-deficient (HDD) quasars that show very weak emission thoroughly from the near-IR to the far-IR, and (2) warm-dust-deficient (WDD) quasars that have similar hot dust emission as normal quasars but are relatively faint in the mid- and far-IR. After building composite AGN templates for these dust-deficient quasars, we successfully fit the 0.3–500 μm SEDs of the PG sample with the appropriate AGN template, an infrared template of a star-forming galaxy, and a host galaxy stellar template. 20 HDD and 12 WDD quasars are identified from the SED decomposition, including seven ambiguous cases. Compared with normal quasars, the HDD quasars have AGNs with relatively low Eddington ratios and the fraction of WDD quasars increases with AGN luminosity. Moreover, both the HDD and WDD quasar populations show relatively stronger mid-IR silicate emission. Virtually identical SED properties are also found in some quasars from z = 0.5 to 6. We propose a conceptual model to demonstrate that the observed dust deficiency of quasars can result from a change of structures of the circumnuclear tori that can occur at any cosmic epoch.

  6. Infrared solar physics from the South Pole

    Science.gov (United States)

    Deming, Drake

    1989-01-01

    Infrared (IR) observations of the sun could greatly benefit from the quality of the South Pole as an IR site, and the potential for multi-day sequences of uninterrupted observations. A nearly continuous picture of the evolution of the magnetic field in solar active regions could be obtained using vector magnetographs, especially vector magnetographs which incorporate IR array detectors. Observations of the sun over a range of wavelengths in the IR continuum could also be used to study the vertical propagation characteristics of the solar p-mode oscillations.

  7. Automated Fast Screening Method for Cocaine Identification in Seized Drug Samples Using a Portable Fourier Transform Infrared (FT-IR) Instrument.

    Science.gov (United States)

    Mainali, Dipak; Seelenbinder, John

    2016-05-01

    Quick and presumptive identification of seized drug samples without destroying evidence is necessary for law enforcement officials to control the trafficking and abuse of drugs. This work reports an automated screening method to detect the presence of cocaine in seized samples using portable Fourier transform infrared (FT-IR) spectrometers. The method is based on the identification of well-defined characteristic vibrational frequencies related to the functional group of the cocaine molecule and is fully automated through the use of an expert system. Traditionally, analysts look for key functional group bands in the infrared spectra and characterization of the molecules present is dependent on user interpretation. This implies the need for user expertise, especially in samples that likely are mixtures. As such, this approach is biased and also not suitable for non-experts. The method proposed in this work uses the well-established "center of gravity" peak picking mathematical algorithm and combines it with the conditional reporting feature in MicroLab software to provide an automated method that can be successfully employed by users with varied experience levels. The method reports the confidence level of cocaine present only when a certain number of cocaine related peaks are identified by the automated method. Unlike library search and chemometric methods that are dependent on the library database or the training set samples used to build the calibration model, the proposed method is relatively independent of adulterants and diluents present in the seized mixture. This automated method in combination with a portable FT-IR spectrometer provides law enforcement officials, criminal investigators, or forensic experts a quick field-based prescreening capability for the presence of cocaine in seized drug samples. © The Author(s) 2016.

  8. Infrared radiation scene generation of stars and planets in celestial background

    Science.gov (United States)

    Guo, Feng; Hong, Yaohui; Xu, Xiaojian

    2014-10-01

    An infrared (IR) radiation generation model of stars and planets in celestial background is proposed in this paper. Cohen's spectral template1 is modified for high spectral resolution and accuracy. Based on the improved spectral template for stars and the blackbody assumption for planets, an IR radiation model is developed which is able to generate the celestial IR background for stars and planets appearing in sensor's field of view (FOV) for specified observing date and time, location, viewpoint and spectral band over 1.2μm ~ 35μm. In the current model, the initial locations of stars are calculated based on midcourse space experiment (MSX) IR astronomical catalogue (MSX-IRAC) 2 , while the initial locations of planets are calculated using secular variations of the planetary orbits (VSOP) theory. Simulation results show that the new IR radiation model has higher resolution and accuracy than common model.

  9. Evaluation of 2,4-D removal via activated carbon from pomegranate husk/polymer composite hydrogel: Optimization of process parameters through face centered composite design

    International Nuclear Information System (INIS)

    Taktak, Fulya; Ilbay, Zeynep; Sahin, Selin

    2015-01-01

    A new type of polymer composite hydrogel was prepared by introducing activated carbons from pomegranate husk into poly ((2-dimethylamino) ethyl methacrylate) network. The removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution was studied with respect to pH of the media, initial 2,4-D concentration and activated carbon content into the polymeric network. Face centered composite design (FCCD) through response surface methodology (RSM) was used for designing the experiments as well as for studying the effects of the process parameters. A quadratic model and a two factor interaction design model were developed for the removal of 2,4-D and adsorption capacity, respectively. The optimum pH of the pesticide solution, activated carbon content into the polymeric network and initial concentration of 2,4-D were found as 3, 2.5 wt% and 100mg/L. 63.245% and 68.805 (mg/g) for the removal of 2,4-D and adsorption capacity were obtained by using Simplex optimization method. Furthermore, the surface characteristics of the adsorbent prepared under optimized conditions were examined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR).

  10. Evaluation of 2,4-D removal via activated carbon from pomegranate husk/polymer composite hydrogel: Optimization of process parameters through face centered composite design

    Energy Technology Data Exchange (ETDEWEB)

    Taktak, Fulya; Ilbay, Zeynep [Usak Univ, Usak (Turkmenistan); Sahin, Selin [Istanbul University, Istanbul (Turkmenistan)

    2015-09-15

    A new type of polymer composite hydrogel was prepared by introducing activated carbons from pomegranate husk into poly ((2-dimethylamino) ethyl methacrylate) network. The removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution was studied with respect to pH of the media, initial 2,4-D concentration and activated carbon content into the polymeric network. Face centered composite design (FCCD) through response surface methodology (RSM) was used for designing the experiments as well as for studying the effects of the process parameters. A quadratic model and a two factor interaction design model were developed for the removal of 2,4-D and adsorption capacity, respectively. The optimum pH of the pesticide solution, activated carbon content into the polymeric network and initial concentration of 2,4-D were found as 3, 2.5 wt% and 100mg/L. 63.245% and 68.805 (mg/g) for the removal of 2,4-D and adsorption capacity were obtained by using Simplex optimization method. Furthermore, the surface characteristics of the adsorbent prepared under optimized conditions were examined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR).

  11. Discrimination and chemical phylogenetic study of seven species of Dendrobium using infrared spectroscopy combined with cluster analysis

    Science.gov (United States)

    Luo, Congpei; He, Tao; Chun, Ze

    2013-04-01

    Dendrobium is a commonly used and precious herb in Traditional Chinese Medicine. The high biodiversity of Dendrobium and the therapeutic needs require tools for the correct and fast discrimination of different Dendrobium species. This study investigates Fourier transform infrared spectroscopy followed by cluster analysis for discrimination and chemical phylogenetic study of seven Dendrobium species. Despite the general pattern of the IR spectra, different intensities, shapes, peak positions were found in the IR spectra of these samples, especially in the range of 1800-800 cm-1. The second derivative transformation and alcoholic extracting procedure obviously enlarged the tiny spectral differences among these samples. The results indicated each Dendrobium species had a characteristic IR spectra profile, which could be used to discriminate them. The similarity coefficients among the samples were analyzed based on their second derivative IR spectra, which ranged from 0.7632 to 0.9700, among the seven Dendrobium species, and from 0.5163 to 0.9615, among the ethanol extracts. A dendrogram was constructed based on cluster analysis the IR spectra for studying the chemical phylogenetic relationships among the samples. The results indicated that D. denneanum and D. crepidatum could be the alternative resources to substitute D. chrysotoxum, D. officinale and D. nobile which were officially recorded in Chinese Pharmacopoeia. In conclusion, with the advantages of high resolution, speediness and convenience, the experimental approach can successfully discriminate and construct the chemical phylogenetic relationships of the seven Dendrobium species.

  12. Infrared Lunar Laser Ranging at Calern : Impact on Lunar Dynamics

    Science.gov (United States)

    Viswanathan, Vishnu; Fienga, Agnes; Manche, Herve; Gastineau, Mickael; Courde, Clement; Torre, Jean Marie; Exertier, Pierre; Laskar, Jacques

    2017-04-01

    Introduction: Since 2015, in addition to the traditional green (532nm), infrared (1064nm) has been the preferred wavelength for lunar laser ranging at the Calern lunar laser ranging (LLR) site in France. Due to the better atmospheric transmission of IR with respect to Green, nearly 3 times the number of normal points have been obtained in IR than in Green [1]. Dataset: In our study, in addition to the historical data obtained from various other LLR sites, we include the recent IR normal points obtained from Calern over the 1 year time span (2015-2016), constituting about 4.2% of data spread over 46 years of LLR. Near even distribution of data provided by IR on both the spatial and temporal domain, helps us to improve constraints on the internal structure of the Moon modeled within the planetary ephemeris : INPOP [2]. Data reduction: IERS recommended models have been used in the data reduction software GINS (GRGS,CNES) [3]. Constraints provided by GRAIL [4], on the Lunar gravitational potential and Love numbers have been taken into account in the least-square fit procedure. Earth orientation parameters from KEOF series have been used as per a recent study [5]. Results: New estimates on the dynamical parameters of the lunar core will be presented. Acknowledgements: We thank the lunar laser ranging observers at Observatoire de la Côte d'Azur, France, McDonald Observatory, Texas, Haleakala Observatory, Hawaii, and Apache Point Observatory in New Mexico for providing LLR observations that made this study possible. The research described in this abstract was carried out at Geoazur-CNRS, France, as a part of a PhD thesis funded by Observatoire de Paris and French Ministry of Education and Research. References: [1] Clement C. et al. (2016) submitted to A&A [2] Fienga A. et al. (2015) Celest Mech Dyn Astr, 123: 325. doi:10.1007/s10569-015-9639-y [3] Viswanathan V. et al. (2015) EGU, Abstract 18, 13995 [4] Konopliv A. S. et al. (2013) J. Geophys. Res. Planets, 118, 1415

  13. On formation mechanism of Pd-Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH3)4][IrCl6

    Science.gov (United States)

    Asanova, Tatyana I.; Asanov, Igor P.; Kim, Min-Gyu; Gerasimov, Evgeny Yu.; Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V.

    2013-10-01

    The formation mechanism of Pd-Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH3)4][IrCl6] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 °C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd-Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10-200 nm) and dendrite Ir-rich (10-50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd-Ir nanoparticles, were found to occur.

  14. On formation mechanism of Pd–Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH3)4][IrCl6

    International Nuclear Information System (INIS)

    Asanova, Tatyana I.; Asanov, Igor P.; Kim, Min-Gyu; Gerasimov, Evgeny Yu.; Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V.

    2013-01-01

    The formation mechanism of Pd–Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH 3 ) 4 ][IrCl 6 ] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 °C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd–Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10–200 nm) and dendrite Ir-rich (10–50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd–Ir nanoparticles, were found to occur.Graphical Abstract

  15. HOMA1-IR and HOMA2-IR indexes in identifying insulin resistance and metabolic syndrome - Brazilian Metabolic Syndrome Study (BRAMS)

    OpenAIRE

    Geloneze, B; Vasques, ACJ; Stabe, CFC; Pareja, JC; Rosado, LEFPD; de Queiroz, EC; Tambascia, MA

    2009-01-01

    Objective: To investigate cut-off values for HOMA1-IR and HOMA2-IR to identify insulin resistance (IR) and metabolic syndrome (MS), and to assess the association of the indexes with components of the MS. Methods: Nondiabetic subjects from the Brazilian Metabolic Syndrome Study were studied (n = 1,203, 18 to 78 years). The cut-off values for IR were determined from the 9011 percentile in the healthy group (n = 297) and, for MS, a ROC curve was generated for the total sample. Results: In the he...

  16. Infrared and Raman Spectra of and Isotopomers: A DFT-PT2 Anharmonic Study

    Directory of Open Access Journals (Sweden)

    Andrea Alparone