WorldWideScience

Sample records for strong infrared radiation

  1. Infrared radiation

    International Nuclear Information System (INIS)

    Moss, C.E.; Ellis, R.J.; Murray, W.E.; Parr, W.H.

    1989-01-01

    All people are exposed to IR radiation from sunlight, artificial light and radiant heating. Exposures to IR are quantified by irradiance and radiant exposure to characterize biological effects on the skin and cornea. However, near-IR exposure to the retina requires knowledge of the radiance of the IR source. With most IR sources in everyday use the health risks are considered minimal; only in certain high radiant work environments are individuals exposed to excessive levels. The interaction of IR radiation with biological tissues is mainly thermal. IR radiation may augment the biological response to other agents. The major health hazards are thermal injury to the eye and skin, including corneal burns from far-IR, heat stress, and retinal and lenticular injury from near-IR radiation. 59 refs, 13 figs, 2 tabs

  2. Thermal infrared anomalies of several strong earthquakes.

    Science.gov (United States)

    Wei, Congxin; Zhang, Yuansheng; Guo, Xiao; Hui, Shaoxing; Qin, Manzhong; Zhang, Ying

    2013-01-01

    In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of "time-frequency relative power spectrum." (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting.

  3. Thermal Infrared Anomalies of Several Strong Earthquakes

    Directory of Open Access Journals (Sweden)

    Congxin Wei

    2013-01-01

    Full Text Available In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1 There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of “time-frequency relative power spectrum.” (2 There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3 Thermal radiation anomalies are closely related to the geological structure. (4 Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting.

  4. Thermal Infrared Anomalies of Several Strong Earthquakes

    Science.gov (United States)

    Wei, Congxin; Guo, Xiao; Qin, Manzhong

    2013-01-01

    In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of “time-frequency relative power spectrum.” (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting. PMID:24222728

  5. Solar and infrared radiation measurements

    CERN Document Server

    Vignola, Frank; Michalsky, Joseph

    2012-01-01

    The rather specialized field of solar and infrared radiation measurement has become more and more important in the face of growing demands by the renewable energy and climate change research communities for data that are more accurate and have increased temporal and spatial resolution. Updating decades of acquired knowledge in the field, Solar and Infrared Radiation Measurements details the strengths and weaknesses of instruments used to conduct such solar and infrared radiation measurements. Topics covered include: Radiometer design and performance Equipment calibration, installation, operati

  6. Infrared Radiative Properties of Food Materials

    Science.gov (United States)

    Precisely, infrared radiation is electromagnetic radiation whose wavelength is longer than that of visible light, but shorter than that of terahertz radiation and microwaves. The infrared portion of the electromagnetic spectrum spans roughly three orders of magnitude (750 nm to 100 µm) and has been...

  7. Relativistically strong electromagnetic radiation in a plasma

    Science.gov (United States)

    Bulanov, S. V.; Esirkepov, T. Zh.; Kando, M.; Kiriyama, H.; Kondo, K.

    2016-03-01

    Physical processes in a plasma under the action of relativistically strong electromagnetic waves generated by high-power lasers have been briefly reviewed. These processes are of interest in view of the development of new methods for acceleration of charged particles, creation of sources of bright hard electromagnetic radiation, and investigation of macroscopic quantum-electrodynamical processes. Attention is focused on nonlinear waves in a laser plasma for the creation of compact electron accelerators. The acceleration of plasma bunches by the radiation pressure of light is the most efficient regime of ion acceleration. Coherent hard electromagnetic radiation in the relativistic plasma is generated in the form of higher harmonics and/or electromagnetic pulses, which are compressed and intensified after reflection from relativistic mirrors created by nonlinear waves. In the limit of extremely strong electromagnetic waves, radiation friction, which accompanies the conversion of radiation from the optical range to the gamma range, fundamentally changes the behavior of the plasma. This process is accompanied by the production of electron-positron pairs, which is described within quantum electrodynamics theory.

  8. Infrared synchrotron radiation from electron storage rings

    International Nuclear Information System (INIS)

    Duncan, W.D.; Williams, G.P.

    1983-01-01

    Simple and useful approximations, valid at infrared wavelengths, to the equations for synchrotron radiation are presented and used to quantify the brightness and power advantage of current synchrotron radiation light sources over conventional infrared broadband laboratory sources. The Daresbury Synchrotron Radiation Source (SRS) and the Brookhaven National Synchrotron Light Source (vacuum ultraviolet) [NSLS(VUV)] storage rings are used as examples in the calculation of the properties of infrared synchrotron radiation. The pulsed nature of the emission is also discussed, and potential areas of application for the brightness, power, and time structure advantages are presented. The use of infrared free electron lasers and undulators on the next generation of storage ring light sources is briefly considered

  9. Coherence and quasistable states in a strong infrared field

    Science.gov (United States)

    Zhong, Changchun; Robicheaux, F.

    2016-03-01

    We study the quasistability of UV-pulse-train-excited H atoms in a strong infrared (IR) laser as a function of the phase delay of the UV pulse train relative to the IR laser. The UV pulse train contains two frequency components. When the two components have frequencies separated by two IR photons, the population of surviving electrons is modulated by up to ten percent. When electrons are excited to right above or below the threshold, the survival probabilities have inverted phase delay dependence, which can be explained classically. When the two frequencies are one IR photon apart, the angular symmetry of the quasistable electrons is broken, and the asymmetry is also controlled by the phase delay. The asymmetrical distribution can be observed while the IR is on and smoothly evolves to a nonzero asymmetry that only weakly depends on the duration of the IR field.

  10. Infrared microspectroscopy with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Carr, G.L.; Williams, G.P. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source

    1997-09-01

    Infrared microspectroscopy with a high brightness synchrotron source can achieve a spatial resolution approaching the diffraction limit. However, in order to realize this intrinsic source brightness at the specimen location, some care must be taken in designing the optical system. Also, when operating in diffraction limited conditions, the effective spatial resolution is no longer controlled by the apertures typically used for a conventional (geometrically defined) measurement. Instead, the spatial resolution depends on the wavelength of light and the effective apertures of the microscope`s Schwarzchild objectives. The authors have modeled the optical system from the synchrotron source up to the sample location and determined the diffraction-limited spatial distribution of light. Effects due to the dependence of the synchrotron source`s numerical aperture on wavelength, as well as the difference between transmission and reflection measurement modes, are also addressed. Lastly, they examine the benefits (when using a high brightness source) of an extrinsic germanium photoconductive detector with cone optics as a replacement for the standard MCT detector.

  11. Wheat germ stabilization by infrared radiation.

    Science.gov (United States)

    Gili, Renato D; Palavecino, Pablo M; Cecilia Penci, M; Martinez, Marcela L; Ribotta, Pablo D

    2017-01-01

    Wheat germ has an important enzymatic activity, being lipases the enzymes which cause the highest impact in the reduction of shelf life. The objective of this study was to evaluate the effects of infrared radiation on wheat germ stabilization in an attempt to extend the shelf life. The effects of treatment time, gap (sample distance to IR emitters) and infrared radiation intensity on wheat germ were analyzed through response surface methodology. Final moisture content, final temperature, color of germ and germ oil quality parameters: free fatty acid content changes and total tocopherol content were the responses evaluated using a Box-Behnken design. A combination of an infrared radiation intensity of 4800 W/m 2 , a 3 min treatment and 0.2 m emitter-sample distance were the best processing condition to stabilize the wheat germ without significantly reduction of the tocopherol content. A confirmatory experiment was conducted with these optimal conditions, and the heat-treated and raw germ samples were stored for 90 days at room temperature in three layer packages to protect them against light and oxygen. The oil quality parameters indicated that the raw germ had a shelf-life of about 15 days, with the heat-treated wheat germ maintaining its quality for at least 90 days under these stored conditions.

  12. Fast Atom Ionization in Strong Electromagnetic Radiation

    Science.gov (United States)

    Apostol, M.

    2018-05-01

    The Goeppert-Mayer and Kramers-Henneberger transformations are examined for bound charges placed in electromagnetic radiation in the non-relativistic approximation. The consistent inclusion of the interaction with the radiation field provides the time evolution of the wavefunction with both structural interaction (which ensures the bound state) and electromagnetic interaction. It is shown that in a short time after switching on the high-intensity radiation the bound charges are set free. In these conditions, a statistical criterion is used to estimate the rate of atom ionization. The results correspond to a sudden application of the electromagnetic interaction, in contrast with the well-known ionization probability obtained by quasi-classical tunneling through classically unavailable non-stationary states, or other equivalent methods, where the interaction is introduced adiabatically. For low-intensity radiation the charges oscillate and emit higher-order harmonics, the charge configuration is re-arranged and the process is resumed. Tunneling ionization may appear in these circumstances. Extension of the approach to other applications involving radiation-induced charge emission from bound states is discussed, like ionization of molecules, atomic clusters or proton emission from atomic nuclei. Also, results for a static electric field are included.

  13. Atomica ionization by strong coherent radiation

    International Nuclear Information System (INIS)

    Brandi, H.S.; Davidovich, L.

    1979-07-01

    The relation among the three most frequently used non-perturbative methods proposed to study the ionization of atoms by strong electromagnetic fields is established. Their range of validity is also determined. (Author) [pt

  14. The Visualization of Infrared Radiation Using Thermal Sensitive Foils

    Science.gov (United States)

    Bochnícek, Zdenek

    2013-01-01

    This paper describes a set of demonstration school experiments where infrared radiation is detected using thermal sensitive foils. The possibility of using standard glass lenses for infrared imaging is discussed in detail. It is shown that with optic components made from glass, infrared radiation up to 2.5 µm of wavelength can be detected. The…

  15. Synchrotron radiation in strongly coupled conformal field theories

    OpenAIRE

    Athanasiou, Christiana; Chesler, Paul M.; Liu, Hong; Nickel, Dominik; Rajagopal, Krishna

    2010-01-01

    Using gauge/gravity duality, we compute the energy density and angular distribution of the power radiated by a quark undergoing circular motion in strongly coupled ${\\cal N}=4$ supersymmetric Yang-Mills (SYM) theory. We compare the strong coupling results to those at weak coupling, and find the same angular distribution of radiated power, up to an overall prefactor. In both regimes, the angular distribution is in fact similar to that of synchrotron radiation produced by an electron in circula...

  16. Hawking radiation and strong gravity black holes

    International Nuclear Information System (INIS)

    Qadir, A.; Sayed, W.A.

    1979-01-01

    It is shown that the strong gravity theory of Salam et al. places severe restrictions on black hole evaporation. Two major implications are that: mini blck holes (down to masses approximately 10 -16 kg) would be stable in the present epoch; and that some suggested mini black hole mechanisms to explain astrophysical phenomena would not work. The first result implies that f-gravity appears to make black holes much safer by removing the possibility of extremely violent black hole explosions suggested by Hawking. (Auth.)

  17. 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.

  18. Effect of infrared radiation on the lens

    Directory of Open Access Journals (Sweden)

    Aly Eman

    2011-01-01

    Full Text Available Background: Infrared (IR radiation is becoming more popular in industrial manufacturing processes and in many instruments used for diagnostic and therapeutic application to the human eye. Aim : The present study was designed to investigate the effect of IR radiation on rabbit′s crystalline lens and lens membrane. Materials and Methods: Fifteen New Zealand rabbits were used in the present work. The rabbits were classified into three groups; one of them served as control. The other two groups were exposed to IR radiation for 5 or 10 minutes. Animals from these two irradiated groups were subdivided into two subgroups; one of them was decapitated directly after IR exposure, while the other subgroup was decapitated 1 hour post exposure. IR was delivered from a General Electric Lamp model 250R 50/10, placed 20 cm from the rabbit and aimed at each eye. The activity of Na + -K + ATPase was measured in the lens membrane. Soluble lens proteins were extracted and the following measurements were carried out: estimation of total soluble protein, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE and Fourier transform infrared (FTIR spectroscopy. For comparison between multiple groups, analysis of variance was used with significance level set at P < 0.001. Results: The results indicated a change in the molecular weight of different lens crystalline accompanied with changes in protein backbone structure. These changes increased for the groups exposed to IR for 10 minutes. Moreover, the activity of Na + -K + ATPase significantly decreased for all groups. Conclusions: The protein of eye lens is very sensitive to IR radiation which is hazardous and may lead to cataract.

  19. Infrared synchrotron radiation instrumentation and applications

    Science.gov (United States)

    Hirschmugl, Carol

    1992-08-01

    Infrared synchrotron radiation (IRSR) is a blossoming field which has three working beamlines, U41R at the National Synchrotron Light Source, Brookhaven National Laboratory, USA, and two at the Institute of Molecular Sciences in Okasaki, Japan, with extensive research projects. There are also several new beamlines in the planning and development stages, both in the United States and abroad. IRSR offers a unique way to access the far infrared (30 μm to ˜ 1mm), which is a notoriously difficult region to work in. In particular, experiments that demand high brightness are well suited to IRSR just as they are in the X-ray region. The central issue in all of the experiments to date has been good signal to noise, which has been the focus of the instrumentation improvements at the U41R beamline. A commercial Fourier transform instrument was the chosen spectrometer. Then modifications were made in order to expand the usable region of the existing experiments, in both the far and near infrared. As an example of the performance of this beamline, I will focus on the reflection absorption spectroscopy results for adsorbates on clean surfaces in ultrahigh vacuum.

  20. Black silicon-based infrared radiation source

    Science.gov (United States)

    Anwar, Momen; Sabry, Yasser; Basset, Philippe; Marty, Frédéric; Bourouina, Tarik; Khalil, Diaa

    2016-03-01

    Micromachined infrared sources are enabling component for interferometric and spectroscopic sensors. Their compact size and low cost transform bulky instruments to the sensor scale, which is needed for a wide range of applications in the conventional and unconventional environments. The silicon micromachined sources should be engineered to have good emissivity across a large wavelength range because the intrinsic emissivity of silicon is low. This optimization was reported in literature by either the deposition of black metal at the surface of an emitter or the use of deep phonic crystal cavities, which complicates the fabrication technology and results in sharp dip lines in the spectral emissivity, respectively. In this work we report a micromachined infrared radiation source based on a heater on the top of black silicon structure for the first time in the literature, up to the authors' knowledge. The temperature of the device is characterized versus the applied voltage and the radiated spectrum is captured in the 1300 nm to 2500 nm spectral range; limited by the spectrum analysis instrument. The reported source opens the doors for completely integrated MEMS spectral sensors onchip.

  1. Synchrotron radiation in strongly coupled conformal field theories

    Science.gov (United States)

    Athanasiou, Christiana; Chesler, Paul M.; Liu, Hong; Nickel, Dominik; Rajagopal, Krishna

    2010-06-01

    Using gauge/gravity duality, we compute the energy density and angular distribution of the power radiated by a quark undergoing circular motion in strongly coupled N=4 supersymmetric Yang-Mills theory. We compare the strong coupling results to those at weak coupling, finding them to be very similar. In both regimes, the angular distribution of the radiated power is in fact similar to that of synchrotron radiation produced by an electron in circular motion in classical electrodynamics: the quark emits radiation in a narrow beam along its velocity vector with a characteristic opening angle α˜1/γ. To an observer far away from the quark, the emitted radiation appears as a short periodic burst, just like the light from a lighthouse does to a ship at sea. Our strong coupling results are valid for any strongly coupled conformal field theory with a dual classical gravity description.

  2. Strong anti-radiation research of nuclear monitoring instrument

    International Nuclear Information System (INIS)

    Xiong Jianping; Zhang Songshou

    2002-01-01

    Strong anti-radiation research of nuclear monitoring instrument is a main question for study. The author introduces the research circumstance. The text recounts the important cause and adoptable measures

  3. The infrared radiation effect to the trismus recovery after odontectomy

    Directory of Open Access Journals (Sweden)

    Arian Reza Marwan

    2007-07-01

    Full Text Available Impacted was defined as unerupted teeth, it could some pathological conditions such as pain, swelling, trismus, and should be removed by an operative procedure called odontectomy. Nevertheless, this procedure could cause some complications such as pain, trismus and swelling. Trismus was a jaw restricted movement condition caused by inflammation, swelling and pain. Trismus could be cured by analgetic anti-inflammation medicines, and physiotherapy such as jaw movement exercise, massaging, hot wet application and therapy used infrared light. Infrared light was an electromagnetic radiation with a wavelength between 0.7 μm-1000 μm. It could reduce the inflammation in cell structure, pain and less of side effects. The research was carried out to know the infrared effect to the velocity of trismus recovery. Type of research had been used is quacy experimental in a prospective way, using 15 patients with infrared radiation and 15 patients without infrared radiation. The result of research used t-test with α = 0.05 indicated that there was significant differences velocity of trismus after odontectomy recovery between infrared radiation and without infrared radiation. This study concluded that the velocity of trismus recovery was faster when applied by infrared radiation.

  4. Radiative electron-atom collision in a strong laser field

    International Nuclear Information System (INIS)

    Faisal, F.H.M.

    1984-01-01

    The comment is concerned with certain current problems and prospects in the theory of electron-atom collision in a strong radiation field. High energy off-shell electron-photon excitation of atoms; low-energy e-atom radiative scattering; steady state input distribution; typical distribution; low energy phenomena; and extensions of the close coupling and the algebraic methods, are all discussed. (U.K.)

  5. Observation of strong magnetic effects in visible-infrared sum frequency generation from magnetic structures

    NARCIS (Netherlands)

    Kirilyuk, A.; Knippels, G.M.H.; van der Meer, A. F. G.; Renard, S.; Rasing, T.; Heskamp, I. R.; Lodder, J. C.

    2000-01-01

    We have observed very strong magnetization-induced changes of the infrared-visible sum-frequency generation (SFG) intensity from thin magnetic films using a free electron laser as a tunable infrared source. With the help of a magnetic grating a clear resonance is observed due to the excitation of

  6. Studies on the hyperthermic effect of the body on utilization of far infrared radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Yong Wun; Cho, Chul Ku; Kim, Kyung Jung [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-12-01

    This study investigated that strong heat reaction of far infrared radiation material could have the possibility for hyperthermia in patients. Objective was CaSki cell, human uterocervical cancer cell line and they observed descending effect remarkably to compare the effect of cell death by high temperature due to far infrared radiation, platelet numbers of experimental group to compare the control were increased 7 {approx} 17%, and lymphocyte numbers 20 {approx} 40 %. High acidity in tumor tissue due to the concentration of lactic acid, so the effects of far infrared had the result to the possibility to reduce the fatigue stuff. The secretion of endorphin as cerebroneuron substance than epinephrine, sympathetic nerve substance could be reduction of pain in cancer patients because of the effect of far infrared. Above data of experiment, we were found multiple the biological efficacy of far infrared about the possibility of medical utilization. (author). 10 refs., 4 tabs., 3 figs.

  7. Analysis of polymer foil heaters as infrared radiation sources

    International Nuclear Information System (INIS)

    Witek, Krzysztof; Piotrowski, Tadeusz; Skwarek, Agata

    2012-01-01

    Infrared radiation as a heat source is used in many fields. In particular, the positive effect of far-infrared radiation on living organisms has been observed. This paper presents two technological solutions for infrared heater production using polymer-silver and polymer-carbon pastes screenprinted on foil substrates. The purpose of this work was the identification of polymer layers as a specific frequency range IR radiation sources. The characterization of the heaters was determined mainly by measurement of the surface temperature distribution using a thermovision camera and the spectral characteristics were determined using a special measuring system. Basic parameters obtained for both, polymer silver and polymer carbon heaters were similar and were as follows: power rating of 10–12 W/dm 2 , continuous working surface temperature of 80–90 °C, temperature coefficient of resistance (TCR) about +900 ppm/K for polymer-carbon heater and about +2000 ppm/K for polymer-silver, maximum radiation intensity in the wavelength range of 6–14 μm with top intensity at 8.5 μm and heating time about 20 min. For comparison purposes, commercial panel heater was tested. The results show that the characteristics of infrared polymer heaters are similar to the characteristics of the commercial heater, so they can be taken into consideration as the alternative infrared radiation sources.

  8. An inter-comparison of far-infrared line-by-line radiative transfer models

    International Nuclear Information System (INIS)

    Kratz, D.P.; Mlynczak, M.G.; Mertens, C.J.Christopher J.; Brindley, Helen; Gordley, L.L.; Martin-Torres, Javier; Miskolczi, F.M.; Turner, D.D.

    2005-01-01

    A considerable fraction (>40%) of the outgoing longwave radiation escapes from the Earth's atmosphere-surface system within a region of the spectrum known as the far-infrared (wave-numbers less than 650 cm -1 ). Dominated by the line and continuum spectral features of the pure rotation band of water vapor, the far-infrared has a strong influence upon the radiative balance of the troposphere, and hence upon the climate of the Earth. Despite the importance of the far-infrared contribution, however, very few spectrally resolved observations have been made of the atmosphere for wave-numbers less than 650 cm -1 . The National Aeronautics and Space Administration (NASA), under its Instrument Incubator Program (IIP), is currently developing technology that will enable routine, space-based spectral measurements of the far-infrared. As part of NASA's IIP, the Far-Infrared Spectroscopy of the Troposphere (FIRST) project is developing an instrument that will have the capability of measuring the spectrum over the range from 100 to 1000 cm -1 at a resolution of 0.6 cm -1 . To properly analyze the data from the FIRST instrument, accurate radiative transfer models will be required. Unlike the mid-infrared, however, no inter-comparison of codes has been performed for the far-infrared. Thus, in parallel with the development of the FIRST instrument, an investigation has been undertaken to inter-compare radiative transfer models for potential use in the analysis of far-infrared measurements. The initial phase of this investigation has focused upon the inter-comparison of six distinct line-by-line models. The results from this study have demonstrated remarkably good agreement among the models, with differences being of order 0.5%, thereby providing a high measure of confidence in our ability to accurately compute spectral radiances in the far-infrared

  9. Far infrared radiation (FIR): its biological effects and medical applications.

    Science.gov (United States)

    Vatansever, Fatma; Hamblin, Michael R

    2012-11-01

    Far infrared (FIR) radiation (λ = 3-100 μm) is a subdivision of the electromagnetic spectrum that has been investigated for biological effects. The goal of this review is to cover the use of a further sub-division (3- 12 μm) of this waveband, that has been observed in both in vitro and in vivo studies, to stimulate cells and tissue, and is considered a promising treatment modality for certain medical conditions. Technological advances have provided new techniques for delivering FIR radiation to the human body. Specialty lamps and saunas, delivering pure FIR radiation (eliminating completely the near and mid infrared bands), have became safe, effective, and widely used sources to generate therapeutic effects. Fibers impregnated with FIR emitting ceramic nanoparticles and woven into fabrics, are being used as garments and wraps to generate FIR radiation, and attain health benefits from its effects.

  10. Feasibility of Jujube peeling using novel infrared radiation heating technology

    Science.gov (United States)

    Infrared (IR) radiation heating has a promising potential to be used as a sustainable and effective method to eliminate the use of water and chemicals in the jujube-peeling process and enhance the quality of peeled products. The objective of this study was to investigate the feasibility of use IR he...

  11. Rectenna that converts infrared radiation to electrical energy

    Energy Technology Data Exchange (ETDEWEB)

    Davids, Paul; Peters, David W.

    2016-09-06

    Technologies pertaining to converting infrared (IR) radiation to DC energy are described herein. In a general embodiment, a rectenna comprises a conductive layer. A thin insulator layer is formed on the conductive layer, and a nanoantenna is formed on the thin insulator layer. The thin insulator layer acts as a tunnel junction of a tunnel diode.

  12. Numerical Study on Similarity of Plume’s Infrared Radiation from Reduced Scaling Solid Rocket

    Directory of Open Access Journals (Sweden)

    Xiaoying Zhang

    2015-01-01

    Full Text Available Similarity of plume radiation between reduced scaling solid rocket models and full scale ones in ground conditions has been taken for investigation. Flow and radiation of plume from solid rockets with scaling ratio from 0.1 to 1 have been computed. The radiative transfer equation (RTE is solved by the finite volume method (FVM in infrared band 2~6 μm. The spectral characteristics of plume gases have been calculated with the weighted-sum-of-gray-gas (WSGG model, and those of the Al2O3 particles have been solved by the Mie scattering model. Our research shows that, with the decreasing scaling ratio of the rocket engine, the radiation intensity of the plume decreases with 1.5~2.5 power of the scaling ratio. The infrared radiation of the plume gases shows a strong spectral dependency, while that of the Al2O3 particles shows grey property. Spectral radiation intensity of the high temperature core of the solid rocket plume increases greatly in the peak absorption spectrum of plume gases. Al2O3 particle is the major radiation composition in the rocket plume, whose scattering coefficient is much larger than its absorption coefficient. There is good similarity between spectral variations of plumes from different scaling solid rockets. The directional plume radiation rises with the increasing azimuth angle.

  13. Polarization and Strong Infra-Red Activity in Compressed Solid Hydrogen

    OpenAIRE

    Souza, Ivo; Martin, Richard M.

    1998-01-01

    Under a pressure of ~150 GPa solid molecular hydrogen undergoes a phase transition accompanied by a dramatic rise in infra-red absorption in the vibron frequency range. We use the Berry's phase approach to calculate the electric polarization in several candidate structures finding large, anisotropic dynamic charges and strongly IR-active vibron modes. The polarization is shown to be greatly affected by the overlap between the molecules in the crystal, so that the commonly used Clausius-Mossot...

  14. Quantum optical signatures in strong-field laser physics: Infrared photon counting in high-order-harmonic generation.

    Science.gov (United States)

    Gonoskov, I A; Tsatrafyllis, N; Kominis, I K; Tzallas, P

    2016-09-07

    We analytically describe the strong-field light-electron interaction using a quantized coherent laser state with arbitrary photon number. We obtain a light-electron wave function which is a closed-form solution of the time-dependent Schrödinger equation (TDSE). This wave function provides information about the quantum optical features of the interaction not accessible by semi-classical theories. With this approach we can reveal the quantum optical properties of high harmonic generation (HHG) process in gases by measuring the photon statistics of the transmitted infrared (IR) laser radiation. This work can lead to novel experiments in high-resolution spectroscopy in extreme-ultraviolet (XUV) and attosecond science without the need to measure the XUV light, while it can pave the way for the development of intense non-classical light sources.

  15. Radiation effects on relativistic electrons in strong external fields

    International Nuclear Information System (INIS)

    Iqbal, Khalid

    2013-01-01

    The effects of radiation of high energy electron beams are a major issue in almost all types of charged particle accelerators. The objective of this thesis is both the analytical and numerical study of radiation effects. Due to its many applications the study of the self force has become a very active and productive field of research. The main part of this thesis is devoted to the study of radiation effects in laser-based plasma accelerators. Analytical models predict the existence of radiation effects. The investigation of radiation reaction show that in laser-based plasma accelerators, the self force effects lower the energy gain and emittance for moderate energies electron beams and increase the relative energy spread. However, for relatively high energy electron beams, the self radiation and retardation (radiation effects of one electron on the other electron of the system) effects increase the transverse emittance of the beam. The energy gain decreases to even lower value and relative energy spread increases to even higher value due to high radiation losses. The second part of this thesis investigates with radiation reaction in focused laser beams. Radiation effects are very weak even for high energy electrons. The radiation-free acceleration and the simple practical setup make direct acceleration in a focused laser beam very attractive. The results presented in this thesis can be helpful for the optimization of future electron acceleration experiments, in particular in the case of laser-plasma accelerators.

  16. Effects of ultraviolet radiation, visible light, and infrared radiation on erythema and pigmentation: a review.

    Science.gov (United States)

    Sklar, Lindsay R; Almutawa, Fahad; Lim, Henry W; Hamzavi, Iltefat

    2013-01-01

    The effects of ultraviolet radiation, visible light, and infrared radiation on cutaneous erythema, immediate pigment darkening, persistent pigment darkening, and delayed tanning are affected by a variety of factors. Some of these factors include the depth of cutaneous penetration of the specific wavelength, the individual skin type, and the absorption spectra of the different chromophores in the skin. UVB is an effective spectrum to induce erythema, which is followed by delayed tanning. UVA induces immediate pigment darkening, persistent pigment darkening, and delayed tanning. At high doses, UVA (primarily UVA2) can also induce erythema in individuals with skin types I-II. Visible light has been shown to induce erythema and a tanning response in dark skin, but not in fair skinned individuals. Infrared radiation produces erythema, which is probably a thermal effect. In this article we reviewed the available literature on the effects of ultraviolet radiation, visible light, and infrared radiation on the skin in regards to erythema and pigmentation. Much remains to be learned on the cutaneous effects of visible light and infrared radiation.

  17. Development of infrared communication in radiation protection and monitoring

    International Nuclear Information System (INIS)

    Thakur, Vaishali M.; Choithramani, S.J.; Sharma, D.N.; Abani, M.C.

    2003-01-01

    Infra-red communication has many important applications in instrumentation and control. Different types of nuclear instruments are used for radiation protection and surveillance program. The application of this mode of communication in these instruments helps in monitoring of inaccessible or high radiation field areas by avoiding undue exposure to the occupational worker. The demand for remotely controlled monitoring instruments and wireless data communication in the mobile computing environment has rapidly increased. This is due to the increasing need for on-line radiological data analysis with minimum human interventions, especially so if the monitoring is in hazardous environment. The wireless communication can be achieved using different communication methodology for short and long range communication. The infrared based communication is used for different applications for short range up to 9-10 meters. The use of this mode of communication has been implemented in some of the radiation monitoring instruments developed in house. The evaluation of data communication using this mode was conducted for the systems like Environmental Radiation Monitor (ERM) and results showed that data communication error is less than 0.1% up to 10 meter distance. (author)

  18. 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.

  19. Noncontact localized internal infrared radiation measurement using an infrared point detector

    Science.gov (United States)

    Hisaka, Masaki

    2017-12-01

    The techniques for temperature measurement within the human body are important for clinical applications. A method for noncontact local infrared (IR) radiation measurements was investigated deep within an object to simulate how the core human body temperature can be obtained. To isolate the IR light emitted from a specific area within the object from the external noise, the radiating IR light was detected using an IR point detector, which comprises a pinhole and a thermopile positioned at an imaging relation with the region of interest within the object. The structure of the helical filament radiating IR light inside a light bulb was thermally imaged by scanning the bulb in two dimensions. Moreover, this approach was used to effectively measure IR light in the range of human body temperature using a glass plate placed in front of the heat source, mimicking the ocular fundus.

  20. Thermal radiators with embedded pulsating heat pipes: Infra-red thermography and simulations

    International Nuclear Information System (INIS)

    Hemadri, Vadiraj A.; Gupta, Ashish; Khandekar, Sameer

    2011-01-01

    With the aim of exploring potential applications of Pulsating Heat Pipes (PHP), for space/terrestrial sectors, experimental study of embedded PHP thermal radiators, having two different effective Biot numbers respectively, and subjected to conjugate heat transfer conditions on their surface, i.e., natural convection and radiation, has been carried out under different thermo-mechanical boundary conditions. High resolution infrared camera is used to obtain spatial temperature profiles of the radiators. To complement the experimental study, detailed 3D computational heat transfer simulation has also been undertaken. By embedding PHP structures, it was possible to make the net thermal resistance of the mild steel radiator plate equivalent to the aluminum radiator plate, in spite of the large difference in their respective thermal conductivities (k Al ∼ 4k MS ). The study reveals that embedded PHP structures can be beneficial only under certain boundary conditions. The degree of isothermalization achieved in these structures strongly depends on its effective Biot number. The relative advantage of embedded PHP is appreciably higher if the thermal conductivity of the radiator plate material itself is low. The study indicates that the effective thermal conductivity of embedded PHP structure is of the order of 400 W/mK to 2300 W/mK, depending on the operating conditions. - Research highlights: → Study of radiator plates with embedded Pulsating Heat Pipe by infrared thermography. → Radiator is subjected to natural convection and radiation boundary conditions. → Experimental study is supported by 3D simulation. → Effective thermal conductivity of PHPs of the order of 2000 W/mK is obtained. → Efficacy of embedded PHPs depends on the effective Biot number of the system.

  1. 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.

  2. Plasma lasers (a strong source of coherent radiation in astrophysics)

    Science.gov (United States)

    Papadopoulos, K.

    1981-01-01

    The generation of electromagnetic radiation from the free energy available in electron streams is discussed. The fundamental principles involved in a particular class of coherent plasma radiation sources, i.e., plasma lasers, are reviewed, focusing on three wave coupling, nonlinear parametric instabilities, and negative energy waves. The simplest case of plasma lasers, that of an unmagnetized plasma containing a finite level of density fluctuations and electrons streaming with respect to the ions, is dealt with. A much more complicated application of plasma lasers to the case of auroral kilometric radiation is then examined. The concept of free electron lasers, including the role of relativistic scattering, is elucidated. Important problems involving the escape of the excited radiation from its generation region, effects due to plasma shielding and nonlinear limits, are brought out.

  3. Dose detection of radiated rice by infrared spectroscopy and chemometrics.

    Science.gov (United States)

    Shao, Yongni; He, Yong; Wu, Changqing

    2008-06-11

    Infrared spectroscopy based on sensitive wavelengths (SWs) and chemometrics was proposed to discriminate the nine different radiation doses (0, 250, 500, 750, 1000, 1500, 2000, 2500, and 3000 Gy) of rice. Samples ( n = 16 each dose) were selected randomly for the calibration set, and the remaining 36 samples ( n = 4 each dose) were selected for the prediction set. Partial least-squares (PLS) analysis and least-squares-support vector machine (LS-SVM) were implemented for calibration models. PLS analysis was implemented for calibration models with different wavelength bands including near-infrared (NIR) regions and mid-infrared (MIR) regions. The best PLS models were achieved in the MIR (400-4000 cm (-1)) region. Furthermore, different latent variables (5-9 LVs) were used as inputs of LS-SVM to develop the LV-LS-SVM models with a grid search technique and radial basis function (RBF) kernel. The optimal models were achieved with six LVs, and they outperformed PLS models. Moreover, independent component analysis (ICA) was executed to select several SWs based on loading weights. The optimal LS-SVM model was achieved with SWs (756, 895, 1140, and 2980 cm (-1)) selected by ICA and had better performance than PLS and LV-LS-SVM with the parameters of correlation coefficient ( r), root-mean-square error of prediction, and bias of 0.996, 80.260, and 5.172 x 10 (-4), respectively. The overall results indicted that the ICA was an effective way for the selection of SWs, and infrared spectroscopy combined with LS-SVM models had the capability to predict the different radiation doses of rice.

  4. Intensification of ultraviolet-induced dermal damage by infrared radiation

    International Nuclear Information System (INIS)

    Kligman, L.H.

    1982-01-01

    To assess the role of IR in actinic damage to the dermis, albino guinea pigs were irradiated for 45 weeks with UV-B and UV-A, with and without IR. Control animals received IR only or no irradiation at all. Unirradiated dermis contains small amounts of elastic fibers in the upper dermis with greater depositions around follicles and sebaceous glands. After irradiation with UV, the fibers became more numerous, thicker, and more twisted; IR alone producd many fine, feathery fibers. The addition of IR to UV resulted in dense matlike elastic fiber depositions that exceeded what was observed with either irradiation alone. In combination or alone UV and IR radiation produced a large increase in ground substance, a finding also seen in actinically damaged human skin. Infrared radiation, in the physiologic range, though pleasant is not innocuous. (orig./MG) [de

  5. Combined visible and near-infrared OPA for wavelength scaling experiments in strong-field physics

    Science.gov (United States)

    Lloyd, David T.; O'Keeffe, Kevin; Wyatt, Adam S.; Anderson, Patrick N.; Treacher, Daniel; Hooker, Simon M.

    2017-02-01

    We report the operation of an optical parametric amplifier (OPA) capable of producing gigawatt peak-power laser pulses with tunable wavelength in either the visible or near-infrared spectrum. The OPA has two distinct operation modes (i) generation of > 350 μJ, sub 100 fs pulses, tunable between 1250 - 1550 nm; (ii) generation of > 170 μJ, sub 150 fs pulses tunable between 490 - 530 nm. We have recorded high-order harmonic spectra over a wide range of driving wavelengths. This flexible source of femtosecond pulses presents a useful tool for exploring the wavelength-dependence of strong-field phenomena, in both the multi-photon and tunnel ionization regimes.

  6. Determining the infrared radiative effects of Saharan dust: a radiative transfer modelling study based on vertically resolved measurements at Lampedusa

    Science.gov (United States)

    Meloni, Daniela; di Sarra, Alcide; Brogniez, Gérard; Denjean, Cyrielle; De Silvestri, Lorenzo; Di Iorio, Tatiana; Formenti, Paola; Gómez-Amo, José L.; Gröbner, Julian; Kouremeti, Natalia; Liuzzi, Giuliano; Mallet, Marc; Pace, Giandomenico; Sferlazzo, Damiano M.

    2018-03-01

    Detailed measurements of radiation, atmospheric and aerosol properties were carried out in summer 2013 during the Aerosol Direct Radiative Impact on the regional climate in the MEDiterranean region (ADRIMED) campaign in the framework of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx) experiment. This study focusses on the characterization of infrared (IR) optical properties and direct radiative effects of mineral dust, based on three vertical profiles of atmospheric and aerosol properties and IR broadband and narrowband radiation from airborne measurements, made in conjunction with radiosonde and ground-based observations at Lampedusa, in the central Mediterranean. Satellite IR spectra from the Infrared Atmospheric Sounder Interferometer (IASI) are also included in the analysis. The atmospheric and aerosol properties are used as input to a radiative transfer model, and various IR radiation parameters (upward and downward irradiance, nadir and zenith brightness temperature at different altitudes) are calculated and compared with observations. The model calculations are made for different sets of dust particle size distribution (PSD) and refractive index (RI), derived from observations and from the literature. The main results of the analysis are that the IR dust radiative forcing is non-negligible and strongly depends on PSD and RI. When calculations are made using the in situ measured size distribution, it is possible to identify the refractive index that produces the best match with observed IR irradiances and brightness temperatures (BTs). The most appropriate refractive indices correspond to those determined from independent measurements of mineral dust aerosols from the source regions (Tunisia, Algeria, Morocco) of dust transported over Lampedusa, suggesting that differences in the source properties should be taken into account. With the in situ size distribution and the most appropriate refractive index the estimated dust IR radiative forcing

  7. Infrared exponents and the strong-coupling limit in lattice Landau gauge

    International Nuclear Information System (INIS)

    Sternbeck, Andre; Smekal, Lorenz von

    2010-01-01

    We study the gluon and ghost propagators of lattice Landau gauge in the strong-coupling limit β=0 in pure SU(2) lattice gauge theory to find evidence of the conformal infrared behavior of these propagators as predicted by a variety of functional continuum methods for asymptotically small momenta q 2 QCD 2 . In the strong-coupling limit, this same behavior is obtained for the larger values of a 2 q 2 (in units of the lattice spacing a), where it is otherwise swamped by the gauge-field dynamics. Deviations for a 2 q 2 <1 are well parameterized by a transverse gluon mass ∝1/a. Perhaps unexpectedly, these deviations are thus no finite-volume effect but persist in the infinite-volume limit. They furthermore depend on the definition of gauge fields on the lattice, while the asymptotic conformal behavior does not. We also comment on a misinterpretation of our results by Cucchieri and Mendes (Phys. Rev. D 81:016005, 2010). (orig.)

  8. Lightning initiation: Strong pulses of VHF radiation accompany preliminary breakdown

    Czech Academy of Sciences Publication Activity Database

    Kolmašová, Ivana; Santolík, Ondřej; Defer, E.; Rison, W.; Coquillat, S.; Pedeboy, S.; Lán, Radek; Uhlíř, Luděk; Lambert, D.; Pinty, J.P.; Prieur, S.; Pont, V.

    2018-01-01

    Roč. 8, č. 1 (2018), č. článku 3650. ISSN 2045-2322 R&D Projects: GA ČR GA17-07027S Grant - others:AV ČR(CZ) AP1401 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:68378289 Keywords : controlled study * article * electromagnetic radiation * magnetic field * waveform * lightning * mapping array * discharges * ionosphere * luminosity * flashes * leaders * system Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics ) Impact factor: 4.259, year: 2016 https://www.nature.com/articles/s41598-018-21972-z

  9. Storing strong spent ionizing-radiation sources in metal matrices

    International Nuclear Information System (INIS)

    Sobolev, I.A.; Arustamov, A.E.; Ozhovan, M.I.; Poluektov, P.P.; Polyakov, A.S.; Semenov, K.N.; Timofeev, E.M.; Tret'yak, S.A.; Shiryaev, V.V.

    1989-01-01

    The Moscow Radon Cooperative has collaborated with the Bochvar Research Institute since 1986 in a new method of handling spent sources for placing in undergound stores. The spent sources are mounted in metal matrices. Each batch of sources after discharge from the containers is enclosed in a layer of metal. This produces firstly uniform activity distribution, which reduces the radiation and thermal loads, and secondly isolates the sources reliably from the environment. Metals are used for the matrices because of the high activity, as metals have good radiation stability and adequate corrosion resistance, while providing good cooling and preventing local overheating. The best matrices are based on lead alloys, which have low melting points, low corrosion rates, low cost, and general availability. Calculations and experience show that the lead consumption is very low and constitutes only 1.35 x 10 -14 cm 3 · Bq -1 (5 x 10 -4 dm 3 ·Ci -1 for 60 Co). The equipment and storage method is described

  10. Strong near-infrared luminescence in BaSnO3.

    Science.gov (United States)

    Mizoguchi, Hiroshi; Woodward, Patrick M; Park, Cheol-Hee; Keszler, Douglas A

    2004-08-11

    Powdered samples of the perovskite BaSnO(3) exhibit strong near-infrared (NIR) luminescence at room temperature, following band-gap excitation at 380 nm (3.26 eV). The emission spectrum is characterized by a broad band centered at 905 nm (1.4 eV), tailing on the high-energy side to approximately 760 nm. The Stokes shift is 1.9 eV, and measured lifetimes in the range 7-18 ms depend on preparative conditions. These extraordinary long values indicate that the luminescence involves a defect state(s). At low temperatures, both a sharp peak and a broad band appear in the visible portion of the luminescence spectrum at approximately 595 nm. Upon cooling, the intensity of the NIR emission decreases, while the integrated intensities of the visible emission features increase to approximately 40% of the NIR intensity at 77 K. Room-temperature photoluminescence (PL) is observed across the Ba(1-x)Sr(x)SnO(3) series. As the strontium content increases, the excitation maximum and band gap shift further into the UV, while the intensity of the NIR emission peak decreases and shifts further into the infrared. This combination leads to an unexpectedly large increase in the Stokes shift. The unusual NIR PL in BaSnO(3) may originate from recombination of a photogenerated valence-band hole and an occupied donor level, probably associated with a Sn(2+) ion situated roughly 1.4 eV above the valence-band edge.

  11. NATO Advanced Research Workshop on Terahertz and Mid Infrared Radiation

    CERN Document Server

    Pereira, Mauro F; Terahertz and Mid Infrared Radiation

    2011-01-01

    Terahertz (THz) and Mid-Infrared (MIR) radiation  (TERA-MIR) can be transmitted through nearly any material without causing biological harm. Novel and rapid methods of detection can be created with devices operation in these spectral ranges allowing scanning for weapons, detecting hidden explosives (including plastic landmines), controlling the quality of food and a host of other exciting applications.  This book focuses on mathematical and physical aspects of the field, on unifying these two spectral domains (THz and MIR) with regard to common sources, detectors, materials and applications, and on key interdisciplinary topics. The main THz and MIR source is the quantum cascade laser (QCL). Thus significant attention is paid to the challenge of turning this advanced technology into affordable commercial devices so as to exploit its enormous potential. However other alternatives to THz QCLs are also presented, e.g.  sub-terahertz imaging from avalanching GaAs bipolar transistors, Josephson junctions as THz ...

  12. Far Infrared Spectrometry of the Cosmic Background Radiation

    Science.gov (United States)

    Mather, J. C.

    1974-01-01

    I describe two experiments to measure the cosmic background radiation near 1 mm wavelength. The first was a ground-based search for spectral lines, made with a Fabry-Perot interferometer and an InSb detector. The second is a measurement of the spectrum from 3 to 18 cm{sup -1}, made with a balloon-borne Fourier transform spectrometer. It is a polarizing Michelson interferometer, cooled in liquid helium, and operated with a germanium bolometer. I give the theory of operation, construction details, and experimental results. The first experiment was successfully completed but the second suffered equipment malfunction on its first flight. I describe the theory of Fourier transformations and give a new understanding of convolutional phase correction computations. I discuss for infrared bolometer calibration procedures, and tabulate test results on nine detectors. I describe methods of improving bolometer sensitivity with immersion optics and with conductive film blackening.

  13. Effects of clouds on limb radiative transfer in the infrared

    Science.gov (United States)

    Ewen, G. B.; Grainger, R. G.; Lambert, A.

    2003-04-01

    A forward model (known as McClouds_FM; the Monte carlo Cloud scattering Forward Model) is developed to predict the influence of cirrus clouds on radiances measured by an infrared limb sounding instrument e.g. MIPAS (Michelson Interferometer Passive Atmospheric Sounder). Areverse method three-dimensional Monte Carlo transfer model is combined with a forward model for radiative transfer through the non-cloudy atmosphere (i.e. the RFM; Reference Forward Model to explicitly account for the effects of multiple scattering by the clouds. The ice cloud microphysics are characterised by a size distribution of randomly oriented ice aggregate crystals, with the single scattering properties of the distribution obtained from T-matrix calculations. McClouds_FM can also be adapted to simulate multiple scattering by water clouds by characterising the cloud microphysics by a size distribution of spheroids and using single scattering properties calculated using Mie theory. Initial results are presented comparing McCloudS_FM simulations and real MIPAS spectra of cirrus showing good agreement. Of particular interest are several noticeable spectral features (i.e. inverted H_2O lines) in the data which are replicated in the simulations and can only be explained by tropospheric radiation scattered into the line of sight by the cloud ice particles. McClouds_FM will be used in a retrieval scheme to determine cloud optical properties from both MIPAS and HIRDLS (HIgh Resolution Dynamic Limb Sounder) infrared limb observations. The RFM was developed by Dr Anu Dudhia at the Department of Atmospheric, Oceanic and Planetary Physics, University of Oxford - http://www.atm.ox.ac.uk/RFM)

  14. A Simple, Student-Built Spectrometer to Explore Infrared Radiation and Greenhouse Gases

    Science.gov (United States)

    Bruce, Mitchell R. M.; Wilson, Tiffany A.; Bruce, Alice E.; Bessey, S. Max; Flood, Virginia J.

    2016-01-01

    In this experiment, students build a spectrometer to explore infrared radiation and greenhouse gases in an inquiry-based investigation to introduce climate science in a general chemistry lab course. The lab is based on the exploration of the thermal effects of molecular absorption of infrared radiation by greenhouse and non-greenhouse gases. A…

  15. Relativistic nonlinear electrodynamics the QED vacuum and matter in super-strong radiation fields

    CERN Document Server

    Avetissian, Hamlet K

    2016-01-01

    This revised edition of the author’s classic 2006 text offers a comprehensively updated review of the field of relativistic nonlinear electrodynamics. It explores the interaction of strong and super-strong electromagnetic/laser radiation with the electromagnetic quantum vacuum and diverse types of matter – including free charged particles and antiparticles, acceleration beams, plasma and plasmous media.  The appearance of laser sources of relativistic and ultra-relativistic intensities over the last decade has stimulated investigation of a large class of processes under such super-strong radiation fields. Revisions for this second edition reflect these developments and the book includes new chapters on Bremsstrahlung and nonlinear absorption of superintense radiation in plasmas, the nonlinear interaction of relativistic atoms with intense laser radiation, nonlinear interaction of strong laser radiation with Graphene, and relativistic nonlinear phenomena in solid-plasma targets under supershort laser pul...

  16. Measurement of Machining Temperature Using Infrared Radiation Pyrometer With Optical Fiber: Characteristics of Pyrometer

    OpenAIRE

    上田, 隆司; 金田, 泰幸; 佐藤, 昌彦; 杉田, 忠彰

    1992-01-01

    The fundamental characteristics of a new type of infrared radiation pyrometer using an optical fiber are investigated theoretically and experimentally. The structure of this pyrometer is that the optical fiber accepts the infrared flux radiated from the object and transmits it to an infrared detector InSb cell. This I. R. P. is suitable for measuring the temperature of a very small object whose temperature changes rapidly. The flexibility of the optical fiber also makes it possible to measure...

  17. Coherence and quasi-stable states in a strong infrared field

    Science.gov (United States)

    Zhong, Changchun; Robicheaux, Francis

    2016-05-01

    We study the quasi-stability of UV-pulse-train-excited H atoms in a strong infrared (IR) laser as a function of the phase delay of the UV-pulse-train relative to the IR laser. The UV-pulse-train contains two frequency components. When the two components have frequencies separated by two IR photons, the population of surviving electrons is modulated by up to ten percent. When electrons are excited to right above or below the threshold, the survival probabilities have inverted phase delay dependence which can be explained classically. When the two frequencies are one IR-photon apart, the angular symmetry of the quasi-stable electrons is broken, and the asymmetry is also controlled by the phase delay. The asymmetrical distribution can be observed while the IR is on and smoothly evolves to a nonzero asymmetry that only weakly depends on the duration of the IR field. This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award No. DE-SC0012193.

  18. Collisional and infrared radiative pumping of molecular vibrational states - The carbon monoxide infrared bands

    Science.gov (United States)

    Scoville, N. Z.; Krotkov, R.; Wang, D.

    1980-09-01

    An analysis of the nonlocal thermodynamic equilibrium resulting from collisions, direct pumping of infrared radiation, and UV fluorescence was made to identify the observational 'signatures' and estimate the efficiency of each process in production of vibrational line protons. The relative populations of the vibrational levels are characterized by a single excitation temperature for all modes of excitation; this is shown by the solution of the full rate equations governing the statistical equilibrium of the CO level populations. The high emissivities estimated for the CO IR band indicate that CO will dominate over H2 in the cooling of high-temperature molecular gas at densities above 10 to the 7th/cu cm; such conditions occur in a shock-heated gas in the cores of molecular clouds or in protostellar nebulae.

  19. Strong far-infrared cooling lines, peculiar CO kinematics, and possible star-formation suppression in Hickson compact group 57

    Energy Technology Data Exchange (ETDEWEB)

    Alatalo, K.; Appleton, P. N.; Ogle, P. M.; Rich, J. A.; Xu, C. K. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Lisenfeld, U. [Departamento de Física Teórica y del Cosmos, Universidad de Granada, E-18071 Granada (Spain); Bitsakis, T. [NASA Herschel Science Center, IPAC, California Institute of Technology, Pasadena, CA 91125 (United States); Guillard, P. [Institut d' Astrophysique Spatiale, Université Paris-Sud XI, F-91405 Orsay Cedex (France); Charmandaris, V. [Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, National Observatory of Athens, GR-15236 Penteli (Greece); Cluver, M.; Jarrett, T. [Astrophysics Cosmology and Gravity Centre, Dept of Astronomy, University of Cape Town, Private Bag X3, Rondebosch, 7701, Republic of South Africa (South Africa); Dopita, M. A.; Kewley, L. J. [Research School of Astronomy and Astrophysics, Australian National University, Cotter Road, Weston, ACT 2611 (Australia); Freeland, E. [The Oskar Klein Centre, Department of Astronomy, AlbaNova, Stockholm University, SE-106 91 Stockholm (Sweden); Rasmussen, J. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Verdes-Montenegro, L. [Departamento Astronomía Extragaláctica, Instituto Astrofísica Andalucía (CSIC), Glorieta de la Astronomía s/n, E-18008 Granada (Spain); Yun, M., E-mail: kalatalo@ipac.caltech.edu [University of Massachusetts, Astronomy Department, Amherst, MA 01003 (United States)

    2014-11-10

    We present [C II] and [O I] observations from Herschel and CO(1-0) maps from the Combined Array for Research in Millimeter Astronomy (CARMA) of the Hickson compact group HCG 57, focusing on the galaxies HCG 57a and HCG 57d. HCG 57a has been previously shown to contain enhanced quantities of warm molecular hydrogen consistent with shock or turbulent heating. Our observations show that HCG 57d has strong [C II] emission compared to L {sub FIR} and weak CO(1-0), while in HCG 57a, both the [C II] and CO(1-0) are strong. HCG 57a lies at the upper end of the normal distribution of the [C II]/CO and [C II]/FIR ratios, and its far-infrared (FIR) cooling supports a low-density, warm, diffuse gas that falls close to the boundary of acceptable models of a photon-dominated region. However, the power radiated in the [C II] and warm H{sub 2} emissions have similar magnitudes, as seen in other shock-dominated systems and predicted by recent models. We suggest that shock heating of the [C II] is a viable alternative to photoelectric heating in violently disturbed, diffuse gas. The existence of shocks is also consistent with the peculiar CO kinematics in the galaxy, indicating that highly noncircular motions are present. These kinematically disturbed CO regions also show evidence of suppressed star formation, falling a factor of 10-30 below normal galaxies on the Kennicutt-Schmidt relation. We suggest that the peculiar properties of both galaxies are consistent with a highly dissipative, off-center collisional encounter between HCG 57d and 57a, creating ring-like morphologies in both systems. Highly dissipative gas-on-gas collisions may be more common in dense groups because of the likelihood of repeated multiple encounters. The possibility of shock-induced star-formation suppression may explain why a subset of these HCG galaxies has been found previously to fall in the mid-infrared green valley.

  20. Strong far-infrared cooling lines, peculiar CO kinematics, and possible star-formation suppression in Hickson compact group 57

    International Nuclear Information System (INIS)

    Alatalo, K.; Appleton, P. N.; Ogle, P. M.; Rich, J. A.; Xu, C. K.; Lisenfeld, U.; Bitsakis, T.; Guillard, P.; Charmandaris, V.; Cluver, M.; Jarrett, T.; Dopita, M. A.; Kewley, L. J.; Freeland, E.; Rasmussen, J.; Verdes-Montenegro, L.; Yun, M.

    2014-01-01

    We present [C II] and [O I] observations from Herschel and CO(1-0) maps from the Combined Array for Research in Millimeter Astronomy (CARMA) of the Hickson compact group HCG 57, focusing on the galaxies HCG 57a and HCG 57d. HCG 57a has been previously shown to contain enhanced quantities of warm molecular hydrogen consistent with shock or turbulent heating. Our observations show that HCG 57d has strong [C II] emission compared to L FIR and weak CO(1-0), while in HCG 57a, both the [C II] and CO(1-0) are strong. HCG 57a lies at the upper end of the normal distribution of the [C II]/CO and [C II]/FIR ratios, and its far-infrared (FIR) cooling supports a low-density, warm, diffuse gas that falls close to the boundary of acceptable models of a photon-dominated region. However, the power radiated in the [C II] and warm H 2 emissions have similar magnitudes, as seen in other shock-dominated systems and predicted by recent models. We suggest that shock heating of the [C II] is a viable alternative to photoelectric heating in violently disturbed, diffuse gas. The existence of shocks is also consistent with the peculiar CO kinematics in the galaxy, indicating that highly noncircular motions are present. These kinematically disturbed CO regions also show evidence of suppressed star formation, falling a factor of 10-30 below normal galaxies on the Kennicutt-Schmidt relation. We suggest that the peculiar properties of both galaxies are consistent with a highly dissipative, off-center collisional encounter between HCG 57d and 57a, creating ring-like morphologies in both systems. Highly dissipative gas-on-gas collisions may be more common in dense groups because of the likelihood of repeated multiple encounters. The possibility of shock-induced star-formation suppression may explain why a subset of these HCG galaxies has been found previously to fall in the mid-infrared green valley.

  1. Turbid Media Extinction Coefficient for Near-Infrared Laser Radiation

    International Nuclear Information System (INIS)

    Dreischuh, T; Gurdev, L; Vankov, O; Stoyanov, D; Avramov, L

    2015-01-01

    In this work, extended investigations are performed of the extinction coefficient of Intralipid-20% dilutions in distilled water depending on the Intralipid concentration, for laser radiation wavelengths in the red and near-infrared regions covering the so-called tissue optical window. The extinction is measured by using an approach we have developed recently based on the features of the spatial intensity distribution of laser-radiation beams propagating through semi-infinite turbid media. The measurements are conducted using separately two dilution- containing plexiglass boxes of different sizes and volumes, in order to prove the appropriateness of the assumption of semi-infinite turbid medium. The experimental results for the extinction are in agreement with our previous results and with empiric formulae found by other authors concerning the wavelength dependence of the scattering coefficient of Intralipid – 10% and Intralipid – 20%. They are also in agreement with known data of the water absorptance. It is estimated as well that the wavelengths around 1320 nm would be advantageous for deep harmless sensing and diagnostics of tissues

  2. Strong second-harmonic radiation from a thin silver film with randomly distributed small holes

    CERN Document Server

    Rakov, N; Xiao, M

    2003-01-01

    We report the observation of strong second-harmonic radiation from a thin silver film containing randomly distributed small holes. A pulsed laser beam of wavelength 1064 nm impinges at an angle of incidence 45 deg. on the film, and the reflection is collected by a CCD detector and analysed by a high-resolution spectrometer. Strong second-harmonic radiation was observed at the wavelength of 532 nm with a halfwidth of 40 nm. (letter to the editor)

  3. Biological Effects of Sunlight, Ultraviolet Radiation, Visible Light, Infrared Radiation and Vitamin D for Health.

    Science.gov (United States)

    Holick, Michael F

    2016-03-01

    Humans evolved in sunlight and had depended on sunlight for its life giving properties that was appreciated by our early ancestors. However, for more than 40 years the lay press and various medical and dermatology associations have denounced sun exposure because of its association with increased risk for skin cancer. The goal of this review is to put into perspective the many health benefits that have been associated with exposure to sunlight, ultraviolet A (UVA) ultraviolet B (UVB), visible and infrared radiation. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  4. Research on infrared radiation characteristics of Pyromark1200 high-temperature coating

    Science.gov (United States)

    Song, Xuyao; Huan, Kewei; Dong, Wei; Wang, Jinghui; Zang, Yanzhe; Shi, Xiaoguang

    2014-11-01

    Pyromark 1200 (Tempil Co, USA), which is a type of high-temperature high-emissivity coating, is silicon-based with good thermal radiation performance. Its stably working condition is at the temperature range 589~922 K thus a wide range of applications in industrial, scientific research, aviation, aerospace and other fields. Infrared emissivity is one of the most important factors in infrared radiation characteristics. Data on infrared spectral emissivity of Pyromark 1200 is in shortage, as well as the reports on its infrared radiation characteristics affected by its spray painting process, microstructure and thermal process. The results of this research show that: (1) The coating film critical thickness on the metal base is 10μm according to comparison among different types of spray painting process, coating film thickness, microstructure, which would influence the infrared radiation characteristics of Pyromark 1200 coating. The infrared spectral emissivity will attenuate when the coating film thickness is lower or much higher than that. (2) Through measurements, the normal infrared radiation characteristics is analyzed within the range at the temperature range 573~873 K under normal atmospheric conditions, and the total infrared spectral emissivity of Pyromark 1200 coating is higher than 0.93 in the 3~14 μm wavelength range. (3) The result of 72-hour aging test at the temperature 673 K which studied the effect of thermal processes on the infrared radiation characteristics of the coating shows that the infrared spectral emissivity variation range is approximately 0.01 indicating that Pyromark 1200 coating is with good stability. Compared with Nextel Velvet Coating (N-V-C) which is widely used in optics field, Pyromark 1200 high-temperature coating has a higher applicable temperature and is more suitable for spraying on the material surface which is in long-term operation under high temperature work conditions and requires high infrared spectral emissivity.

  5. Spectral shifting strongly constrains molecular cloud disruption by radiation pressure on dust

    Science.gov (United States)

    Reissl, Stefan; Klessen, Ralf S.; Mac Low, Mordecai-Mark; Pellegrini, Eric W.

    2018-03-01

    Aim. We aim to test the hypothesis that radiation pressure from young star clusters acting on dust is the dominant feedback agent disrupting the largest star-forming molecular clouds and thus regulating the star-formation process. Methods: We performed multi-frequency, 3D, radiative transfer calculations including both scattering and absorption and re-emission to longer wavelengths for model clouds with masses of 104-107 M⊙, containing embedded clusters with star formation efficiencies of 0.009-91%, and varying maximum grain sizes up to 200 μm. We calculated the ratio between radiative and gravitational forces to determine whether radiation pressure can disrupt clouds. Results: We find that radiation pressure acting on dust almost never disrupts star-forming clouds. Ultraviolet and optical photons from young stars to which the cloud is optically thick do not scatter much. Instead, they quickly get absorbed and re-emitted by the dust at thermal wavelengths. As the cloud is typically optically thin to far-infrared radiation, it promptly escapes, depositing little momentum in the cloud. The resulting spectrum is more narrowly peaked than the corresponding Planck function, and exhibits an extended tail at longer wavelengths. As the opacity drops significantly across the sub-mm and mm wavelength regime, the resulting radiative force is even smaller than for the corresponding single-temperature blackbody. We find that the force from radiation pressure falls below the strength of gravitational attraction by an order of magnitude or more for either Milky Way or moderate starbust conditions. Only for unrealistically large maximum grain sizes, and star formation efficiencies far exceeding 50% do we find that the strength of radiation pressure can exceed gravity. Conclusions: We conclude that radiation pressure acting on dust does not disrupt star-forming molecular clouds in any Local Group galaxies. Radiation pressure thus appears unlikely to regulate the star

  6. Experimental observation of strong radiation reaction in the field of an ultra-intense laser

    Science.gov (United States)

    Sarri, G.; Poder, K.; Tamburini, M.; di Piazza, A.; Keitel, C. H.; Zepf, M.

    2017-10-01

    Describing radiation reaction in an electromagnetic field is one of the most fundamental outstanding problems in electrodynamics. It consists of determining the dynamics of a charged particle fully taking into account self-forces (loosely referred to as radiation reaction) resulting from the radiation fields generated by the particle whilst it is accelerated. Radiation reaction has only been invoked to explain the radiative properties of powerful astrophysical objects, such as pulsars and quasars. From a theoretical standpoint, this phenomenon is subject of fervent debate and this impasse is worsened by the lack of experimental data, due to extremely high fields required to trigger these effects. Here, we report on the first experimental evidence of strong radiation reaction during the interaction of an ultra-relativistic electron beam with an intense laser field, beyond a purely classical description.

  7. Infrared

    Science.gov (United States)

    Vollmer, M.

    2013-11-01

    'Infrared' is a very wide field in physics and the natural sciences which has evolved enormously in recent decades. It all started in 1800 with Friedrich Wilhelm Herschel's discovery of infrared (IR) radiation within the spectrum of the Sun. Thereafter a few important milestones towards widespread use of IR were the quantitative description of the laws of blackbody radiation by Max Planck in 1900; the application of quantum mechanics to understand the rotational-vibrational spectra of molecules starting in the first half of the 20th century; and the revolution in source and detector technologies due to micro-technological breakthroughs towards the end of the 20th century. This has led to much high-quality and sophisticated equipment in terms of detectors, sources and instruments in the IR spectral range, with a multitude of different applications in science and technology. This special issue tries to focus on a few aspects of the astonishing variety of different disciplines, techniques and applications concerning the general topic of infrared radiation. Part of the content is based upon an interdisciplinary international conference on the topic held in 2012 in Bad Honnef, Germany. It is hoped that the information provided here may be useful for teaching the general topic of electromagnetic radiation in the IR spectral range in advanced university courses for postgraduate students. In the most general terms, the infrared spectral range is defined to extend from wavelengths of 780 nm (upper range of the VIS spectral range) up to wavelengths of 1 mm (lower end of the microwave range). Various definitions of near, middle and far infrared or thermal infrared, and lately terahertz frequencies, are used, which all fall in this range. These special definitions often depend on the scientific field of research. Unfortunately, many of these fields seem to have developed independently from neighbouring disciplines, although they deal with very similar topics in respect of the

  8. Application of gas-fired infra-red radiator to thermal disinfection of horticultural substrate

    International Nuclear Information System (INIS)

    Wawer, M.; Osiński, A.

    1998-01-01

    The studies were carried out on heating horticultural substrate (moor peat - bark, 1:1 by volume) with a gas-fired infra-red radiator to destroy the pests and pathogens. Minimum distance between radiator and substrate surface was determined considering assumed time of heating. Dynamics of substrate heating was determined depending on its layer thickness and kind of surface under substrate layer; black rubber, ground steel sheet and aluminium foil were used as the surface. Considerable decreasing of infra-red radiation penetrability through the substrate layer above 7 mm thick was found as well as an significant effect of the radiation reflected from the surface under substrate layer on the intensity of its heating. It was also stated that heating horticultural substrates with the gas-fired infra-red radiator enables to rise the temperature of thin substrate layer up to 70 degree of C within relatively short time [pl

  9. Strong electron-phonon interaction in the high-Tc superconductors: Evidence from the infrared

    International Nuclear Information System (INIS)

    Timusk, T.; Porter, C.D.; Tanner, D.B.

    1991-01-01

    We show that low-frequency structure in the infrared reflectance of the high-temperature superconductor YBa 2 Cu 3 O 7 results from the electron-phonon interaction. Characteristic antiresonant line shapes are seen in the phonon region of the spectrum and the frequency-dependent scattering rate of the mid-infrared electronic continuum has peaks at 150 cm -1 (19 meV) and at 360 cm -1 (45 meV) in good agreement with phonon density-of-states peaks in neutron time-of-flight spectra that develop in superconducting samples. The interaction between the phonons and the charge carriers can be understood in terms of a charged-phonon model

  10. Radiation of a circulating quark in strongly coupled N = 4 super Yang-Mills theory

    Science.gov (United States)

    Athanasiou, Christiana; Chesler, Paul M.; Liu, Hong; Nickel, Dominik; Rajagopal, Krishna

    2010-12-01

    The energy density and angular distribution of power radiated by a quark undergoing circular motion in strongly coupled N = 4 supersymmetric Yang-Mills (SYM) theory is computed using gauge/gravity duality. The results are qualitatively similar to that of synchrotron radiation produced by an electron in circular motion in classical electrodynamics: At large velocities the quark emits radiation in a narrow beam along its velocity vector with a characteristic opening angle α˜1/γ and radial thickness scaling like ˜1/γ3.

  11. Eye Safety Related to Near Infrared Radiation Exposure to Biometric Devices

    Directory of Open Access Journals (Sweden)

    Nikolaos Kourkoumelis

    2011-01-01

    Full Text Available Biometrics has become an emerging field of technology due to its intrinsic security features concerning the identification of individuals by means of measurable biological characteristics. Two of the most promising biometric modalities are iris and retina recognition, which primarily use nonionizing radiation in the infrared region. Illumination of the eye is achieved by infrared light emitting diodes (LEDs. Even if few LED sources are capable of causing direct eye damage as they emit incoherent light, there is a growing concern about the possible use of LED arrays that might pose a potential threat. Exposure to intense coherent infrared radiation has been proven to have significant effects on living tissues. The purpose of this study is to explore the biological effects arising from exposing the eye to near infrared radiation with reference to international legislation.

  12. 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)

  13. Cover materials excluding near infrared radiation: effect on greenhouse climate and plant processes

    NARCIS (Netherlands)

    Kempkes, F.L.K.; Stanghellini, C.; Hemming, S.; Dai, J.

    2008-01-01

    Only about half of the energy that enters a greenhouse as sun radiation is in the wavelength range that is useful for photosynthesis (PAR, Photosynthetically Active Radiation). Nearly all the remaining energy fraction is in the Near InfraRed range (NIR) and warms the greenhouse and crop and does

  14. Organic-inorganic hybrid optical foils with strong visible reflection, excellent near infrared-shielding ability and high transparency.

    Science.gov (United States)

    Zhou, Yijie; Huang, Aibin; Zhou, Huaijuan; Ji, Shidong; Jin, Ping

    2018-03-02

    Research on functional flexible films has recently been attracting widespread attention especially with regards to foils, which can be designed artificially on the basis of the practical requirements. In this work, a foil with high visible reflection and a strong near infrared shielding efficiency was prepared by a simple wet chemical method. In the process of making this kind of optical foil, emulsion polymerization was first introduced to synthesize polymer opals, which were further compressed between two pieces of polyethylene terephthalate (PET) foil under polymer melting temperature to obtain a photonic crystal film with a strong reflection in the visible region to block blue rays. The following step was to coat a layer of the inorganic nano paint, which was synthesized by dispersing Cs-doped WO 3 (CWO) nanoparticles homogenously into organic resin on the surface of the PET to achieve a high near infrared shielding ability. The final composite foil exhibited unique optical properties such as high visible reflectance (23.9%) to block blue rays, and excellent near infrared shielding efficiency (98.0%), meanwhile it still maintained a high transparency meaning that this foil could potentially be applied in energy-saving window films. To sum up, this study provides new insight into devising flexible hybrid films with novel optical properties, which could be further extended to prepare other optical films for potential use in automobile, architectural and other decorative fields.

  15. Organic-inorganic hybrid optical foils with strong visible reflection, excellent near infrared-shielding ability and high transparency

    Science.gov (United States)

    Zhou, Yijie; Huang, Aibin; Zhou, Huaijuan; Ji, Shidong; Jin, Ping

    2018-03-01

    Research on functional flexible films has recently been attracting widespread attention especially with regards to foils, which can be designed artificially on the basis of the practical requirements. In this work, a foil with high visible reflection and a strong near infrared shielding efficiency was prepared by a simple wet chemical method. In the process of making this kind of optical foil, emulsion polymerization was first introduced to synthesize polymer opals, which were further compressed between two pieces of polyethylene terephthalate (PET) foil under polymer melting temperature to obtain a photonic crystal film with a strong reflection in the visible region to block blue rays. The following step was to coat a layer of the inorganic nano paint, which was synthesized by dispersing Cs-doped WO3 (CWO) nanoparticles homogenously into organic resin on the surface of the PET to achieve a high near infrared shielding ability. The final composite foil exhibited unique optical properties such as high visible reflectance (23.9%) to block blue rays, and excellent near infrared shielding efficiency (98.0%), meanwhile it still maintained a high transparency meaning that this foil could potentially be applied in energy-saving window films. To sum up, this study provides new insight into devising flexible hybrid films with novel optical properties, which could be further extended to prepare other optical films for potential use in automobile, architectural and other decorative fields.

  16. Experimental Investigations on Drying of Porous Media Using Infrared Radiation

    Directory of Open Access Journals (Sweden)

    A. K. Haghi

    2001-01-01

    Full Text Available Increased interest is being shown in infrared drying today because of the environmental and technological advantages offered by this method. In order to assess the advantages of this drying process, extensive trials have been carried out. The objective of this investigation was to study the drying rate of infrared drying. This was achieved with the use of scanning pyrometer and image analysis. 

  17. Strong suppression of radiation states in a slab waveguide sandwiched between omnidirectional mirrors

    NARCIS (Netherlands)

    Hoekstra, Hugo; Yudistira, D.; Stoffer, Remco

    2005-01-01

    Structures in channel or slab waveguides, applied deliberately or due to imperfections, may lead to strong modal losses, corresponding to the excitation of radiation modes. As an example, losses are generally very large in slab photonic crystal (PhC) impurity waveguides (WGs) due to the combined

  18. Photoprotection beyond ultraviolet radiation--effective sun protection has to include protection against infrared A radiation-induced skin damage.

    Science.gov (United States)

    Schroeder, P; Calles, C; Benesova, T; Macaluso, F; Krutmann, J

    2010-01-01

    Solar radiation is well known to damage human skin, for example by causing premature skin ageing (i.e. photoageing). We have recently learned that this damage does not result from ultraviolet (UV) radiation alone, but also from longer wavelengths, in particular near-infrared radiation (IRA radiation, 760-1,440 nm). IRA radiation accounts for more than one third of the solar energy that reaches human skin. While infrared radiation of longer wavelengths (IRB and IRC) does not penetrate deeply into the skin, more than 65% of the shorter wavelength (IRA) reaches the dermis. IRA radiation has been demonstrated to alter the collagen equilibrium of the dermal extracellular matrix in at least two ways: (a) by leading to an increased expression of the collagen-degrading enzyme matrix metalloproteinase 1, and (b) by decreasing the de novo synthesis of the collagen itself. IRA radiation exposure therefore induces similar biological effects to UV radiation, but the underlying mechanisms are substantially different, specifically, the cellular response to IRA irradiation involves the mitochondrial electron transport chain. Effective sun protection requires specific strategies to prevent IRA radiation-induced skin damage. 2010 S. Karger AG, Basel.

  19. Total molecular gas masses of Planck - Herschel selected strongly lensed hyper luminous infrared galaxies

    Science.gov (United States)

    Harrington, K. C.; Yun, M. S.; Magnelli, B.; Frayer, D. T.; Karim, A.; Weiß, A.; Riechers, D.; Jiménez-Andrade, E. F.; Berman, D.; Lowenthal, J.; Bertoldi, F.

    2018-03-01

    We report the detection of CO(1-0) line emission from seven Planck and Herschel selected hyper luminous ({L_{IR (8-1000{μ m})} > 10^{13} L_{⊙}) infrared galaxies with the Green Bank Telescope (GBT). CO(1-0) measurements are a vital tool to trace the bulk molecular gas mass across all redshifts. Our results place tight constraints on the total gas content of these most apparently luminous high-z star-forming galaxies (apparent IR luminosities of LIR > 1013 - 14 L⊙), while we confirm their predetermined redshifts measured using the Large Millimeter Telescope, LMT (zCO = 1.33-3.26). The CO(1-0) lines show similar profiles as compared to Jup = 2-4 transitions previously observed with the LMT. We report enhanced infrared to CO line luminosity ratios of = 110 ± 22 L_{⊙} (K km s^{-1} pc^{-2})^{-1} compared to normal star-forming galaxies, yet similar to those of well-studied IR-luminous galaxies at high-z. We find average brightness temperature ratios of 〈 r21〉 = 0.93 (2 sources), 〈 r31〉 = 0.34 (5 sources), and 〈 r41〉 = 0.18 (1 source). The r31 and r41 values are roughly half the average values for SMGs. We estimate the total gas mass content as {μ M_{H2} = (0.9-27.2) × 10^{11} (α _CO/0.8) M_{⊙}, where μ is the magnification factor and αCO is the CO line luminosity to molecular hydrogen gas mass conversion factor. The rapid gas depletion times, = 80} Myr, reveal vigorous starburst activity, and contrast the Gyr depletion time-scales observed in local, normal star-forming galaxies.

  20. 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.

  1. Strong Field-Induced Frequency Conversion of Laser Radiation in Plasma Plumes: Recent Achievements

    Directory of Open Access Journals (Sweden)

    R. A. Ganeev

    2013-01-01

    Full Text Available New findings in plasma harmonics studies using strong laser fields are reviewed. We discuss recent achievements in the growth of the efficiency of coherent extreme ultraviolet (XUV radiation sources based on frequency conversion of the ultrashort pulses in the laser-produced plasmas, which allowed for the spectral and structural studies of matter through the high-order harmonic generation (HHG spectroscopy. These studies showed that plasma HHG can open new opportunities in many unexpected areas of laser-matter interaction. Besides being considered as an alternative method for generation of coherent XUV radiation, it can be used as a powerful tool for various spectroscopic and analytical applications.

  2. Vibrational relaxation of CDCl3 induced by infrared laser radiation

    International Nuclear Information System (INIS)

    Alvarez, R.F.; Azcarate, M.L.; Alonso, E.M.; Dangelo, R.J.; Quel, E.J.

    1990-01-01

    A CO 2 TEA laser was used to excite mode ν 4 of CDCl 3 (914cm- 1 ). The laser was constructed at the laboratory, tuned in line 10P(48), (10.91 μm). Infrared fluorescence technique was used to determine V-T/R relaxation times for CDCl 3 both pure and in Ar mixtures. (Author). 9 refs., 3 figs

  3. Efficacy of Six Weeks Infrared Radiation Therapy on Chronic Low ...

    African Journals Online (AJOL)

    TNHJOURNALPH

    obtained before the study commenced, while individual patient's informed consent was duly obtained before their participation. Infrared therapy was applied to subjects' low back region in prone lying, after being tested for thermal sensation using test tubes containing cold and warm water respectively. The patients' low back.

  4. Strong restriction on inflationary vacua from the local gauge invariance III: Infrared regularity of graviton loops

    International Nuclear Information System (INIS)

    Tanaka, Takahiro; Urakawa, Yuko

    2014-01-01

    It has been claimed that the super-Hubble modes of the graviton generated during inflation can make loop corrections diverge. Even if we introduce an infrared (IR) cutoff at a comoving scale as an ad hoc but practical method of regularization, we encounter secular growth, which may lead to the breakdown of perturbative expansion for a sufficiently long-lasting inflation. In this paper, we show that the IR pathology concerning the graviton can be attributed to the presence of residual gauge degrees of freedom in the local observable universe, as in the case of the adiabatic curvature perturbation. We will show that choosing the Euclidean vacuum as the initial state ensures invariance under the above-mentioned residual gauge transformations. We will also show that, as long as we consider a gauge invariant quantity in the local universe, we encounter neither IR divergence nor secular growth. The argument in this paper applies to general single-field models of inflation up to a sufficiently high order in perturbation

  5. Near-infrared radiation and scattering properties of coal fly ash particles cloud

    Energy Technology Data Exchange (ETDEWEB)

    Itaya, Y.; Nishio, N.; Hatano, S.; Kobayashi, N.; Kobayashi, J.; Mori, S. [Nagoya University, Aichi (Japan). Dept. of Chemical Engineering

    2006-07-15

    Radiation in near infrared region dominates the heat transfer in high temperature processes including particle dispersion such as coal gasification and pulverized coal combustion. The thermal radiation properties in near-infrared region of 0.8-2.2 mu m were studied for a cloud of coal ash particles. The monochromatic absorption as well as the directional behavior of scattering for the sample particles dispersed in liquid paraffin wax were measured spectroscopically at an atmospheric state by using FT-IR. The effect of the particles number density in the cloud and the thickness of the dispersion layer on the spectrum of absorption could be expressed in the property of the extinction efficiency. The spectral distribution of the extinction efficiency is dependent of wavelength in the near-infrared region. The contribution of scattering by ash particles can be ignored, or the forward scattering dominates the particle scattering in the radiative heat transfer in the cloud.

  6. Pion Production from Proton Synchrotron Radiation under Strong Magnetic Field in a Relativistic Quantum Approach

    Directory of Open Access Journals (Sweden)

    Maruyama Tomoyuki

    2016-01-01

    Full Text Available We study pion production from proton synchrotron radiation in the presence of strong magnetic fields by using the exact proton propagator in a strong magnetic field and explicitly including the anomalous magnetic moment. Results in this exact quantum approach do not agree with those obtained in the semi-classical approach. Then, we find that the anomalous magnetic moment of the proton greatly enhances the production rate by about two orders magnitude, and that the decay width satisfies a robust scaling law.

  7. Pion Production from Proton Synchrotron Radiation under Strong Magnetic Field in Relativistic Quantum Approach

    Directory of Open Access Journals (Sweden)

    Maruyama Tomoyuki

    2016-01-01

    Full Text Available We study pion production from proton synchrotron radiation in the presence of strong magnetic fields by using the exact proton propagator in a strong magnetic field and explicitly including the anomalous magnetic moment. Results in this exact quantum-field approach do not agree with those obtained in the semi-classical approach. Furthermore, we also find that the anomalous magnetic moment of the proton greatly enhances the production rate about by two orders of magnitude, and that the polar angle of an emitted pion is the same as that of an initial proton.

  8. Effect of rare earth Ce on the far infrared radiation property of iron ore tailings ceramics

    International Nuclear Information System (INIS)

    Liu, Jie; Meng, Junping; Liang, Jinsheng; Duan, Xinhui; Huo, Xiaoli; Tang, Qingguo

    2015-01-01

    Highlights: • Detailed process proposed for preparation of iron ore tailings ceramics. • Replace natural minerals with iron ore tailings as raw materials for preparing functional ceramics. • Impact mechanism of Ce on far infrared ceramics, as well as its optimum addition amounts can be obtained. • Propose a new perspective on considering the mechanism of far infrared radiation. - Abstract: A kind of far infrared radiation ceramics was prepared by using iron ore tailings, CaCO 3 and SiO 2 as main raw materials, and Ce as additive. The result of Fourier transform infrared spectroscopy showed that the sample exhibits excellent radiation value of 0.914 when doping 7 wt.% Ce. Ce 4+ dissolved into iron diopside and formed interstitial solid solution with it sintered at 1150 °C. The oxidation of Fe 2+ to Fe 3+ caused by Ce 4+ led to a decrease of crystallite sizes and enhancement of Mg–O and Fe–O vibration in iron diopside, which consequently improved the far infrared radiation properties of iron ore tailings ceramics

  9. Application of ultraviolet and infrared radiations in documentoscopy

    International Nuclear Information System (INIS)

    Lopez, Jorgelina Andrea

    2010-01-01

    UV and IR radiation are located outside the visible electromagnetic spectrum, providing relevant service documentoscopic analysis, referring to the words of author Jose Del Picchia we can say that ''sixth sense to be the expert cabinet . Various bodies under its action and substances or emit luminescence radiating a particular energy, and using pinhole cameras, proper lighting and photographic material, as the case of the radiation used can be achieved discover forged documents by physical or chemical action, revealed secret ink, regeneration of original texts eradicated by fraudulent, amendment, deletion, you can achieve the reconstruction of incipient charred documents, among others, are some of the many specific applications of UV and IR electromagnetic radiation. That contribute to the task expert. (author) [es

  10. Effects of strong radiation reaction and quantum-electrodynamics on relativistic transparency

    Science.gov (United States)

    Zhang, Peng; Thomas, A. G. R.; Ridgers, C. P.

    2013-10-01

    Relativistic transparency is the process that optically switches the overdense plasma from opaque to transparent and enables light propagation through the otherwise opaque plasma, when light of sufficient intensity drives the electrons in the plasma to near light speeds. We study the relativistic transparency in radiation dominant and strong quantum electrodynamic (QED) regime, for the interaction of high-intensity laser pulses with a thin foil solid target. We analytically study the simplified motion of an electron in a circularly polarized plane wave to understand the physics of the transmissivity and absorption in the presence of classical and quantum-corrected, semiclassical radiation-reaction forces and the trapping of particles in nodes of laser standing wave through radiative cooling. These arguments are supported by both one dimensional and two dimensional particle-in-cell calculations including strong field QED effects. Measurement of the transmission of these pulses would be experimentally feasible and a robust test of the strong field QED particle-in-cell framework.

  11. Jeans instability in collisional strongly coupled dusty plasma with radiative condensation and polarization force

    Energy Technology Data Exchange (ETDEWEB)

    Prajapati, R. P., E-mail: prajapati-iter@yahoo.co.in; Bhakta, S. [Department of Pure and Applied Physics, Guru Ghasidas Central University, Bilaspur-495009 (C.G.) (India); Chhajlani, R. K. [Retired from School of Studies in Physics, Vikram University, Ujjain-456010 (M.P.) (India)

    2016-05-15

    The influence of dust-neutral collisions, polarization force, and electron radiative condensation is analysed on the Jeans (gravitational) instability of partially ionized strongly coupled dusty plasma (SCDP) using linear perturbation (normal mode) analysis. The Boltzmann distributed ions, dynamics of inertialess electrons, charged dust and neutral particles are considered. Using the plane wave solutions, a general dispersion relation is derived which is modified due to the presence of dust-neutral collisions, strong coupling effect, polarization force, electron radiative condensation, and Jeans dust/neutral frequencies. In the long wavelength perturbations, the Jeans instability criterion depends upon strong coupling effect, polarization interaction parameter, and thermal loss, but it is independent of dust-neutral collision frequency. The stability of the considered configuration is analysed using the Routh–Hurwitz criterion. The growth rates of Jeans instability are illustrated, and stabilizing influence of viscoelasticity and dust-neutral collision frequency while destabilizing effect of electron radiative condensation, polarization force, and Jeans dust-neutral frequency ratio is observed. This work is applied to understand the gravitational collapse of SCDP with dust-neutral collisions.

  12. Strong Focusing Wiggler for SASE and FEL in the Far-Infrared Region at ISIR, Osaka University

    CERN Document Server

    Kashiwagi, S; Kato, R; Noda, N

    2005-01-01

    We apply the edge-focusing scheme to the wiggler for FEL and SASE in the far-infrared region at ISIR, Osaka University in order to make the gain length of SASE shorter by keeping the beam size small along the wiggler. As the electron beam energy is 10-30 MeV and the magnetic field of the wiggler is up to 0.4 T, the natural focusing force in the vertical direction is strong in the wiggler and it is strongly dependent on the electron energy and the wiggler gap. The focusing forces should be compatible to or higher than the strong natural focusing force, equally in the horizontal and vertical directions over the wide range of the electron beam energy and the wiggler gap. In order to meet this requirement, we adopt the strong focusing scheme using the EF wiggler. The wiggler consists of 4 FODO cells in the 1.938 m long (32 periods, period length: 60mm). A focusing element and defocusing element are incorporate with single wiggler periods with edge angles of +5 and -5 degrees, respectively, and they are separated ...

  13. Fourier Transform Infrared Radiation Spectroscopy Applied for Wood Rot Decay and Mould Fungi Growth Detection

    OpenAIRE

    Jelle, Bjørn Petter; Hovde, Per Jostein

    2012-01-01

    Material characterization may be carried out by the attenuated total reflectance (ATR) Fourier transform infrared (FTIR) radiation spectroscopical technique, which represents a powerful experimental tool. The ATR technique may be applied on both solid state materials, liquids, and gases with none or only minor sample preparations, also including materials which are nontransparent to IR radiation. This facilitation is made possible by pressing the sample directly onto various crystals, for exa...

  14. Infrared Radiography: Modeling X-ray Imaging without Harmful Radiation

    Science.gov (United States)

    Zietz, Otto; Mylott, Elliot; Widenhorn, Ralf

    2015-01-01

    Planar x-ray imaging is a ubiquitous diagnostic tool and is routinely performed to diagnose conditions as varied as bone fractures and pneumonia. The underlying principle is that the varying attenuation coefficients of air, water, tissue, bone, or metal implants within the body result in non-uniform transmission of x-ray radiation. Through the…

  15. Effect of Infrared Laser Radiation on Biological Systems.

    Science.gov (United States)

    1973-06-01

    Streptococcus faecium . The deactivation obtained in 60 seconds in the CO2 beam was the equivalent to that produced by a radiation dose of 2.5 M rad...laser pulse of the order of 10-2 seconds duration if all the energy absorbed were taken up by specific vibrational modes of the irradiated molecules

  16. Infrared response of YBa2Cu3O7-δ films to pulsed, broadband synchrotron radiation

    International Nuclear Information System (INIS)

    Carr, G.L.; Quijada, M.; Tanner, D.B.; Etemad, S.; DeRosa, F.; Venkatesan, T.; Dutta, B.; Hemmick, D.; Xi, X.

    1990-01-01

    We report studies of a thin high T c film operating as a fast bolometric detector of infrared radiation. The film has a response of infrared radiation. The film has a response of several mV when exposed to a 1 W, 1 ns duration broadband infrared pulse. The decay after the pulse was about 4 ns. The temperature dependence of the response accurately tracked dR/dT. A thermal model, in which the film's temperature varies relative to the substrate, provides a good description of the response. We find no evidence for other (non-bolometric) response mechanisms for temperatures near or well below T c . 13 refs., 4 figs

  17. A Numerical Simulation for Prediction of Infrared Radiation Emitted from Plain Surfaces with Different Geometries

    Directory of Open Access Journals (Sweden)

    Vakilabadi K.A.

    2017-08-01

    Full Text Available In this paper, infrared radiation exiting plain surfaces with different geometries is numerically simulated. Surfaces under consideration are assumed to have steady uniform heat generation inside. Moreover, the boundaries of the surfaces are considered to be at the surroundings temperature. Infrared radiation is calculated based on the temperature profile determined for the surface. The temperature profile of the surface is determined assuming the two dimensional heat conduction equations to govern the problem. The physical domain is transformed into the appropriate computational domain and the governing equation is mapped into the suitable forms in the new coordinate system of variables. After that the temperature profile of the surface is computed, the infrared radiation distribution of the surface is evaluated based on the equations given in the manuscript. The temperature profile as well as the IR images are given in the results section. It is concluded that the maximum value of infrared radiation of the surface occurs at the center. Moreover, it is concluded that among surfaces with equal areas, the one having the largest perimeter has the least value of IR at its center.

  18. Microprocessing of human hard tooth tissues surface by mid-infrared erbium lasers radiation

    Science.gov (United States)

    Belikov, Andrey V.; Shatilova, Ksenia V.; Skrypnik, Alexei V.

    2015-03-01

    A new method of hard tooth tissues laser treatment is described. The method consists in formation of regular microdefects on tissue surface by mid-infrared erbium laser radiation with propagation ratio M2caries prevention as a result of increasing microhardness and acid resistance of tooth enamel.

  19. Moisture removal characteristics of thin layer rough rice under sequenced infrared radiation heating and cooling

    Science.gov (United States)

    Rice drying with infrared (IR) radiation has been investigated during recent years and showed promising potential with improved quality and energy efficiency. The objective of this study was to further investigate the moisture removal characteristics of thin layer rough rice heated by IR and cooled ...

  20. Efficacy of six weeks infrared radiation therapy on chronic low back ...

    African Journals Online (AJOL)

    The objective of this study was to determine the efficacy of six weeks infrared radiation therapy on pain intensity and functional disability index in subjects suffering from ... pain level and functional disability scores were assessed using the lO point numerical rating pain scale and the Oswestry disability index questionnaire.

  1. University Physics Students' Ideas of Thermal Radiation Expressed in Open Laboratory Activities Using Infrared Cameras

    Science.gov (United States)

    Haglund, Jesper; Melander, Emil; Weiszflog, Matthias; Andersson, Staffan

    2017-01-01

    Background: University physics students were engaged in open-ended thermodynamics laboratory activities with a focus on understanding a chosen phenomenon or the principle of laboratory apparatus, such as thermal radiation and a heat pump. Students had access to handheld infrared (IR) cameras for their investigations. Purpose: The purpose of the…

  2. Internal stray radiation measurement for cryogenic infrared imaging systems using a spherical mirror.

    Science.gov (United States)

    Tian, Qijie; Chang, Songtao; He, Fengyun; Li, Zhou; Qiao, Yanfeng

    2017-06-10

    Internal stray radiation is a key factor that influences infrared imaging systems, and its suppression level is an important criterion to evaluate system performance, especially for cryogenic infrared imaging systems, which are highly sensitive to thermal sources. In order to achieve accurate measurement for internal stray radiation, an approach is proposed, which is based on radiometric calibration using a spherical mirror. First of all, the theory of spherical mirror design is introduced. Then, the calibration formula considering the integration time is presented. Following this, the details regarding the measurement method are presented. By placing a spherical mirror in front of the infrared detector, the influence of internal factors of the detector on system output can be obtained. According to the calibration results of the infrared imaging system, the output caused by internal stray radiation can be acquired. Finally, several experiments are performed in a chamber with controllable inside temperatures to validate the theory proposed in this paper. Experimental results show that the measurement results are in good accordance with the theoretical analysis, and demonstrate that the proposed theories are valid and can be employed in practical applications. The proposed method can achieve accurate measurement for internal stray radiation at arbitrary integration time and ambient temperatures. The measurement result can be used to evaluate whether the suppression level meets the system requirement.

  3. Thermal imaging method to visualize a hidden painting thermally excited by far infrared radiations

    Science.gov (United States)

    Davin, T.; Wang, X.; Chabane, A.; Pawelko, R.; Guida, G.; Serio, B.; Hervé, P.

    2015-06-01

    The diagnosis of hidden painting is a major issue for cultural heritage. In this paper, a non-destructive active infrared thermographic technique was considered to reveal paintings covered by a lime layer. An extended infrared spectral range radiation was used as the excitation source. The external long wave infrared energy source delivered to the surface is then propagated through the material until it encounters a painting zone. Due to several thermal effects, the sample surface then presents non-uniformity patterns. Using a high sensitive infrared camera, the presence of covered pigments can thus be highlighted by the analysis of the non-stationary phenomena. Reconstituted thermal contrast images of mural samples covered by a lime layer are shown.

  4. arXiv Strong reduction of the effective radiation length in an oriented PWO scintillator crystal

    CERN Document Server

    Bandiera, L.; Romagnoni, M.; Argiolas, N.; Bagli, E.; Ballerini, G.; Berra, A.; Brizzolani, C.; Camattari, R.; De Salvador, D.; Haurylavets, V.; Mascagna, V.; Mazzolari, A.; Prest, M.; Soldani, M.; Sytov, A.; Vallazza, E.

    We measured a considerable increase of the emitted radiation by 120 GeV/c electrons in an axially oriented lead tungstate scintillator crystal, if compared to the case in which the sample was not aligned with the beam direction. This enhancement resulted from the interaction of particles with the strong crystalline field. The data collected at the external lines of CERN SPS were critically compared to Monte Carlo simulations based on the Baier Katkov quasiclassical method, highlighting a reduction of the scintillator radiation length by a factor of five in case of beam alignment with the [001] crystal axes. As a consequence, oriented scintillator crystals may be profitably exploited to reduce the amount of material in electromagnetic calorimeters/detectors for fixed-target experiments in high-energy physics, as well as for satellite-borne gamma-telescopes in astrophysics.

  5. Analysis on the steady-state coherent synchrotron radiation with strong shielding

    International Nuclear Information System (INIS)

    Li, R.; Bohn, C.L.; Bisognano, J.J.

    1997-01-01

    There are several papers concerning shielding of coherent synchrotron radiation (CSR) emitted by a Gaussian line charge on a circular orbit centered between two parallel conducting plates. Previous asymptotic analyses in the frequency domain show that shielded steady-state CSR mainly arises from harmonics in the bunch frequency exceeding the threshold harmonic for satisfying the boundary conditions at the plates. In this paper the authors extend the frequency-domain analysis into the regime of strong shielding, in which the threshold harmonic exceeds the characteristic frequency of the bunch. The result is then compared to the shielded steady-state CSR power obtained using image charges

  6. The status of the first infrared beamline at Shanghai Synchrotron Radiation Facility

    International Nuclear Information System (INIS)

    Ji, Te; Tong, Yajun; Zhu, Huachun; Zhang, Zengyan; Peng, Weiwei; Chen, Min; Xiao, Tiqiao; Xu, Hongjie

    2015-01-01

    Construction of the first infrared beamline BL01B1 at Shanghai Synchrotron Radiation Facility (SSRF) was completed at the end of 2013. The IR beamline collects both edge radiation (ER) and bending magnet radiation (BMR) from a port, providing a solid angle of 40 mrad and 20 mrad in the horizontal and vertical directions, respectively. The optical layout of the infrared beamline and the design of the extraction mirror are described in this paper. A calculation of the beam propagation has been used to optimize the parameters of the optical components. The photon flux and spatial resolution have been measured at the end-station, and the experimental results are in good agreement with the theoretical calculation

  7. The status of the first infrared beamline at Shanghai Synchrotron Radiation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Te; Tong, Yajun; Zhu, Huachun; Zhang, Zengyan; Peng, Weiwei; Chen, Min, E-mail: chenmin@sinap.ac.cn; Xiao, Tiqiao; Xu, Hongjie

    2015-07-11

    Construction of the first infrared beamline BL01B1 at Shanghai Synchrotron Radiation Facility (SSRF) was completed at the end of 2013. The IR beamline collects both edge radiation (ER) and bending magnet radiation (BMR) from a port, providing a solid angle of 40 mrad and 20 mrad in the horizontal and vertical directions, respectively. The optical layout of the infrared beamline and the design of the extraction mirror are described in this paper. A calculation of the beam propagation has been used to optimize the parameters of the optical components. The photon flux and spatial resolution have been measured at the end-station, and the experimental results are in good agreement with the theoretical calculation.

  8. The status of the first infrared beamline at Shanghai Synchrotron Radiation Facility

    Science.gov (United States)

    Ji, Te; Tong, Yajun; Zhu, Huachun; Zhang, Zengyan; Peng, Weiwei; Chen, Min; Xiao, Tiqiao; Xu, Hongjie

    2015-07-01

    Construction of the first infrared beamline BL01B1 at Shanghai Synchrotron Radiation Facility (SSRF) was completed at the end of 2013. The IR beamline collects both edge radiation (ER) and bending magnet radiation (BMR) from a port, providing a solid angle of 40 mrad and 20 mrad in the horizontal and vertical directions, respectively. The optical layout of the infrared beamline and the design of the extraction mirror are described in this paper. A calculation of the beam propagation has been used to optimize the parameters of the optical components. The photon flux and spatial resolution have been measured at the end-station, and the experimental results are in good agreement with the theoretical calculation.

  9. Detecting ship targets in spaceborne infrared image based on modeling radiation anomalies

    Science.gov (United States)

    Wang, Haibo; Zou, Zhengxia; Shi, Zhenwei; Li, Bo

    2017-09-01

    Using infrared imaging sensors to detect ship target in the ocean environment has many advantages compared to other sensor modalities, such as better thermal sensitivity and all-weather detection capability. We propose a new ship detection method by modeling radiation anomalies for spaceborne infrared image. The proposed method can be decomposed into two stages, where in the first stage, a test infrared image is densely divided into a set of image patches and the radiation anomaly of each patch is estimated by a Gaussian Mixture Model (GMM), and thereby target candidates are obtained from anomaly image patches. In the second stage, target candidates are further checked by a more discriminative criterion to obtain the final detection result. The main innovation of the proposed method is inspired by the biological mechanism that human eyes are sensitive to the unusual and anomalous patches among complex background. The experimental result on short wavelength infrared band (1.560 - 2.300 μm) and long wavelength infrared band (10.30 - 12.50 μm) of Landsat-8 satellite shows the proposed method achieves a desired ship detection accuracy with higher recall than other classical ship detection methods.

  10. Dynamics of photoprocesses induced by femtosecond infrared radiation in free molecules and clusters of iron pentacarbonyl

    International Nuclear Information System (INIS)

    Kompanets, V. O.; Lokhman, V. N.; Poydashev, D. G.; Chekalin, S. V.; Ryabov, E. A.

    2016-01-01

    The dynamics of photoprocesses induced by femtosecond infrared radiation in free Fe(CO) 5 molecules and their clusters owing to the resonant excitation of vibrations of CO bonds in the 5-μm range has been studied. The technique of infrared excitation and photoionization probing (λ = 400 nm) by femtosecond pulses has been used in combination with time-of-flight mass spectrometry. It has been found that an infrared pulse selectively excites vibrations of CO bonds in free molecules, which results in a decrease in the yield of the Fe(CO) 5 + molecular ion. Subsequent relaxation processes have been analyzed and the results have been interpreted. The time of the energy transfer from excited vibrations to other vibrations of the molecule owing to intramolecular relaxation has been measured. The dynamics of dissociation of [Fe(CO) 5 ] n clusters irradiated by femtosecond infrared radiation has been studied. The time dependence of the yield of free molecules has been measured under different infrared laser excitation conditions. We have proposed a model that well describes the results of the experiment and makes it possible, in particular, to calculate the profile of variation of the temperature of clusters within the “evaporation ensemble” concept. The intramolecular and intracluster vibrational relaxation rates in [Fe(CO) 5 ] n clusters have been estimated.

  11. The role of near infrared radiation in photoaging of the skin.

    Science.gov (United States)

    Schroeder, Peter; Haendeler, Judith; Krutmann, Jean

    2008-07-01

    Infrared (IR) radiation is non-ionizing, electromagnetic radiation with wavelengths between 760 nm and 1 mm, which is further divided into IRA, IRB and IRC. IR accounts for more than half of the solar energy that reaches the human skin. While IRB and IRC do not penetrate deeply into the skin, more than 65% of IRA reaches the dermis. Human skin is increasingly exposed to IRA-radiation; most relevant sources are (i) natural solar radiation consisting of over 30% IRA, (ii) artificial IRA sources used for therapeutic or wellness purposes and (iii) artificial UV sources contaminated with IRA. As part of natural sunlight, IRA significantly contributes to extrinsic skin aging. This article reviews the cutaneous effects of IRA-radiation, the underlying molecular mechanisms and the available protective strategies.

  12. Detector Response and Beam Line Transmission Measurements with Far-Infrared Radiation

    CERN Document Server

    Grimm, O; Fröhlich, L

    2005-01-01

    Various activities at the TTF linear accelerator at DESY, Hamburg, that drives the VUV-FEL are geared towards measuring the longitudinal charge distribution of electron bunches with coherent far-infrared radiation. Examples are beam lines transporting synchrotron or transition radiation to interferometers mounted inside or outside the tunnel, and studies of single-shot grating spectrometers. All such approaches require a good understanding of the radiation generation and transport mechanism and of the detector characteristics to extract useful information on the charge distribution. Simulations and measurements of the expected transverse intensity distribution and polarization of synchrotron radiation emitted at the first bunch compressor of TTF have been performed. The transverse intensity scanning provided for the first time at DESY a visual image of the footprint of terahertz radiation. Detector response measurements have been performed at the FELIX facility, Netherlands, for wavelengths between 100-160 mi...

  13. Radiation by a heavy quark in N=4 SYM at strong coupling

    CERN Document Server

    Hatta, Y; Mueller, A H; Triantafyllopoulos, D N

    2011-01-01

    Using the AdS/CFT correspondence in the supergravity approximation, we compute the energy density radiated by a heavy quark undergoing some arbitrary motion in the vacuum of the strongly coupled N=4 supersymmetric Yang-Mills theory. We find that this energy is fully generated via backreaction from the near-boundary endpoint of the dual string attached to the heavy quark. Because of that, the energy distribution shows the same space-time localization as the classical radiation that would be produced by the heavy quark at weak coupling. We believe that this and some other unnatural features of our result (like its anisotropy and the presence of regions with negative energy density) are artifacts of the supergravity approximation, which will be corrected after including string fluctuations. For the case where the quark trajectory is bounded, we also compute the radiated power, by integrating the energy density over the surface of a sphere at infinity. For sufficiently large times, we find agreement with a previo...

  14. Infrared-microwave double resonance: signal dependence on microwave radiation strength

    NARCIS (Netherlands)

    Vreede, J.P.M. de; Dijkerman, H.A.

    1980-01-01

    The influence of MW radiation on the magnitude of double resonance signals is studied in the case of steady-state 3-level IR-MW double resonance, using IR or MW radiation as probe field. The measurements reveal a strong signal dependence on the microwave power level. Changes in the absorption factor

  15. Possible Mechanism of Infrared Radiation Reception: The Role of the Temperature Factor

    Science.gov (United States)

    Yachnev, I. L.; Penniyaynen, V. A.; Podzorova, S. A.; Rogachevskii, I. V.; Krylov, B. V.

    2018-02-01

    The role of the temperature factor in the mechanism of reception of the CO2 laser low-power infrared (IR) radiation (λ = 10.6 μm) by a sensory neuron membrane has been studied. Organotypic embryonic tissue culture has been used to measure and estimate the temperature of a sensory ganglia monolayer exposed to radiation at different energy densities. The effects of tissue exposure to low-power IR radiation have been investigated. It has been found that inhibition of tissue growth by radiation of low energy density (10-14-10-10 J/cm2) is replaced by tissue growth (10-7-10-4 J/cm2), and again followed by inhibition in the range of 0.1-6 J/cm2. A statistically significant specific reaction to nonthermal radiation has been detected at the radiation power density of 3 × 10-10 J/cm2, which is due to activation of the Na+,K+-ATPase transducer function. The mechanisms of interaction of IR radiation with embryonic nerve tissue have been considered. Low-power IR radiation with the wavelength of 10.6 μm has been demonstrated to specifically activate a novel signal transducer function of the sodium pump, which controls the reception of nonthermal IR radiation in the energy density range of 10-14 to 10-10 J/cm2.

  16. External radiation as element of improvement infrared thermography measurements

    Directory of Open Access Journals (Sweden)

    Palomo, A.

    2000-09-01

    Full Text Available Infrared thermography is a very versatile non destructive technique which among other uses, can be applied to the study of moisture in buildings. However, this particular application can present some problems strictly related to the characteristics of the thermocamera device. In this case the available equipment works in the IR range of 2.5 to 5.6 μm. In this part of the spectrum, there exists a small and not very intense band of emission of the water molecules (approximately centered at 2.7 μm, in such a way that detection can be difficult through thermovision. In the present paper, a complementary technique to the IR thermography being able of favouring the emission of water on the mentioned band, has been developed. It enhances the capacity of detection of the instrument. Likewise, the process which takes place in the material has been numerically modelled.

    La termografía infrarroja es una técnica no destructiva, muy versátil, que, entre otras aplicaciones, tiene la de ser capaz de suministrar información en torno a la problemática de las humedades en la edificación. Sin embargo, esta aplicación concreta puede presentar algunos problemas directamente relacionados con las propias características de la termocámara utilizada. En el caso del presente trabajo el equipo de termografía infrarroja manejado trabaja en el rango del espectro IR comprendido entre 2,5 y 5,6 μm. En esta región del espectro existe una pequeña y no muy intensa banda de emisión de las moléculas de agua (aproximadamente centrada en 2,7 μm cuya detección puede no ser fácil a través de la termovisión. En el presente trabajo se ha desarrollado una técnica complementaria a la termografía infrarroja que es capaz de favorecer la intensidad de emisión del agua en la región del espectro antes mencionada. En definitiva, dicha técnica estimula la capacidad de detección de la termocámara. Adicionalmente, el proceso hídrico que tiene lugar en el

  17. Fullerene decomposition induced by near-infrared laser radiation studied by real-time turbidimetry

    Science.gov (United States)

    Juha, L.; Ehrenberg, B.; Couris, S.; Koudoumas, E.; Hamplová, V.; Pokorná, Z.; Müllerová, A.; Pavel, M.

    1999-11-01

    C 60 and C 70 fullerenes dissolved in toluene or n-hexane have been found to be decomposed by near-infrared Nd:YAG laser radiation even at moderate intensities ( λ=1064 nm, I=35-70 MW/cm 2) quite effectively. Formation of a fine precipitate, occurring during the photolysis, has been studied turbidimetrically. Cubic intensity dependence of the decomposition efficiency was found. The multiphoton dissociation of fullerenes leads to a formation of the fine black precipitate whose particles, overheated by the pulsed laser radiation, cause further decomposition of fullerene cages.

  18. Solar panel thermal cycling testing by solar simulation and infrared radiation methods

    Science.gov (United States)

    Nuss, H. E.

    1980-01-01

    For the solar panels of the European Space Agency (ESA) satellites OTS/MAROTS and ECS/MARECS the thermal cycling tests were performed by using solar simulation methods. The performance data of two different solar simulators used and the thermal test results are described. The solar simulation thermal cycling tests for the ECS/MARECS solar panels were carried out with the aid of a rotatable multipanel test rig by which simultaneous testing of three solar panels was possible. As an alternative thermal test method, the capability of an infrared radiation method was studied and infrared simulation tests for the ultralight panel and the INTELSAT 5 solar panels were performed. The setup and the characteristics of the infrared radiation unit using a quartz lamp array of approx. 15 sq and LN2-cooled shutter and the thermal test results are presented. The irradiation uniformity, the solar panel temperature distribution, temperature changing rates for both test methods are compared. Results indicate the infrared simulation is an effective solar panel thermal testing method.

  19. Exploring how infrared radiation enhances the attractive interaction between a cell pair by its electromagnetic nature

    Science.gov (United States)

    Yang, Bor-Wen; Yeh, Chu; Lin, Po-Cheng; Chao, Chi-Tse

    2013-10-01

    Electromagnetic radiation can be categorized into ionizing and non-ionizing varieties. To determine the mechanism how non-ionizing radiation affects biological cells, we analyzed the difference between its thermal and electromagnetic effects. Two-beam optical tweezers were designed to demonstrate that infrared radiation could enhance the cellular interaction between red blood cells by its electromagnetic nature. An IR spot in the optical tweezers was irradiated on two RBCs to polarize them and induce electromagnetic attraction, while the other focused visible spot was used to quantify the intensity of the intercellular interaction. It was found that 0.1 mW/μm2 infrared radiation was adequate to cause pN-scale interaction between a cell pair, which was only 1/1000 of the power density used in a CD-R drive. We then set up a model to describe how non-ionizing radiation affected a cell assembly by deriving electromagnetic micro-stress transverse to its propagation axis.

  20. Radiation-induced growth and isothermal decay of infrared-stimulated luminescence from feldspar

    DEFF Research Database (Denmark)

    Guralnik, Benny; Li, Bo; Jain, Mayank

    2015-01-01

    the growth and decay of laboratory-regenerated luminescence signals. Here we review a selection of common models describing the response of infrared stimulated luminescence (IRSL) of feldspar to constant radiation and temperature as administered in the laboratory. We use this opportunity to introduce...... by their ability to accurately describe a recently published feldspar multi-elevated temperature post-IR IRSL (MET-pIRIR) dataset, and highlight each model's strengths and shortfalls. © 2015 Elsevier Ltd. All rights reserved....

  1. Infrared Radiation Assisted Stokes’ Law Based Synthesis and Optical Characterization of ZnS Nanoparticles

    OpenAIRE

    Singh, Beer Pal; Upadhyay, Ravish Kumar; Kumar, Rakesh; Yadav, Kamna; Areizaga-Martinez, Hector I.

    2016-01-01

    The strategy and technique exploited in the synthesis of nanostructure materials have an explicit effect on the nucleation, growth, and properties of product materials. Nanoparticles of zinc sulfide (ZnS) have been synthesized by new infrared radiation (IR) assisted and Stokes’ law based controlled bottom-up approach without using any capping agent and stirring. IR has been used for heating the reaction surface designed in accordance with the well-known Stokes law for a free body falling in a...

  2. Infrared radiation increases skin damage induced by other wavelengths in solar urticaria.

    Science.gov (United States)

    de Gálvez, María Victoria; Aguilera, José; Sánchez-Roldán, Cristina; Herrera-Ceballos, Enrique

    2016-09-01

    Photodermatoses are typically investigated by analyzing the individual or combined effects of ultraviolet A (UVA), ultraviolet B (UVB), and visible light using light sources that simulate portions of the solar spectrum. Infrared radiation (IRR), however, accounts for 53% of incident solar radiation, but its effects are not taken into account in standard phototest protocols. The aim was to analyze the effects of IRR, alone and combined with UVA and visible light on solar urticaria lesions, with a distinction between infrared A (IRA) and infrared B (IRB). We performed standard phototests with UVA and visible light in four patients with solar urticaria and also tested the effects after blocking IRB with a water filter. To analyze the direct effect of IRR, we performed phototests with IRA and IRB. Initial standard phototests that were all positive found the induction of erythema and whealing, while when IRR was blocked from the UVA and visible light sources, three of the patients developed no lesions, while the fourth developed a very small wheal. These results suggest that IRR has the potential to produce and exacerbate lesions caused by other types of radiation. Consideration of these effects during phototesting could help prevent diagnostic errors. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Measurement of thermal radiation using regular glass optics and short-wave infrared detectors.

    Science.gov (United States)

    Yoon, H W; Eppeldauer, G P

    2008-01-21

    The measurement of thermal radiation from ambient-temperature objects using short-wave infrared detectors and regular glass optics is described. The detectors are chosen to operate in the 2.0 microm to 2.5 microm atmospheric window. Selection of detectors with high shunt resistance along with the 4-stage thermo-electric cooling of the detectors to -85 degrees C results in detectivity, D*, of 4 x 10(13) cm Hz(1/2)/W which is near the background limited performance at 295 K. Furthermore, the use of regular-glass commercial optics to collect the thermal radiation results in diffraction-limited imaging. The use of a radiation thermometer constructed with these elements for the measurement of a blackbody from 20 degrees C to 50 degrees C results in noise-equivalent temperature difference (NETD) of thermal sensors also leads to lower sensitivity to the emissivity of the object in determining the temperature of the object. These elements are used to construct a calibrator for an infrared collimator, and such a system demonstrates noise-equivalent irradiances of thermal infrared detectors.

  4. The evaluation of non-ionizing radiation (near-infrared radiation) based medical imaging application: Diabetes foot

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Young Jin [Dept. of Radiological Science, Dongseo University, Busan (Korea, Republic of); Shin, Cheol Won; Ahn, Sung Min; Hong, Jun Yong; Ahn, Yun Jin; Lim, Cheong Hwan [Dept. of Radiological Science, Hanseo University, Seosan (Korea, Republic of)

    2016-09-15

    Near-infrared radiation (NIR) is non-ionizing, non-invasive, and deep tissue penetration in biological material, thereby increasing research interests as a medical imaging technique in the world. However, the use of current near-infrared medical image is extremely limited in Korea (ROK) since it is not well known among radiologic technologists and radiological researchers. Therefore to strengthen the knowledge for NIR medical imaging is necessary so as to prepare a qualified radiological professionals to serve medical images in high-quality on the clinical sites. In this study, an overview of the features and principles of N IR imaging was demonstrated. The latest research topics and worldwide research trends were introduced for radiologic technologist to reinforce their technical skills. In particular, wound care and diabetic foot which have high feasibility for clinical translation were introduced in order to contribute to accelerating NIR research for developing the field of radiological science.

  5. The evaluation of non-ionizing radiation (near-infrared radiation) based medical imaging application: Diabetes foot

    International Nuclear Information System (INIS)

    Jung, Young Jin; Shin, Cheol Won; Ahn, Sung Min; Hong, Jun Yong; Ahn, Yun Jin; Lim, Cheong Hwan

    2016-01-01

    Near-infrared radiation (NIR) is non-ionizing, non-invasive, and deep tissue penetration in biological material, thereby increasing research interests as a medical imaging technique in the world. However, the use of current near-infrared medical image is extremely limited in Korea (ROK) since it is not well known among radiologic technologists and radiological researchers. Therefore to strengthen the knowledge for NIR medical imaging is necessary so as to prepare a qualified radiological professionals to serve medical images in high-quality on the clinical sites. In this study, an overview of the features and principles of N IR imaging was demonstrated. The latest research topics and worldwide research trends were introduced for radiologic technologist to reinforce their technical skills. In particular, wound care and diabetic foot which have high feasibility for clinical translation were introduced in order to contribute to accelerating NIR research for developing the field of radiological science

  6. Controlling of hydrogen and oxygen atoms in CdTe by means of far-infrared spectroscopy using synchrotron radiation

    International Nuclear Information System (INIS)

    Cebulski, J.; Sheregii, E.M.; Polit, J.; Marcelli, A.; Robouch, B.; Castelli Gudi, M.; Piccinini, M.; Kisiel, A.

    2007-01-01

    The work presents far-and middle-infrared reflectivity spectra collected with synchrotron radiation on specially prepared CdTe-monocrystals in the temperature region of 30-300 K. The investigated samples were of three different types characterized by the three different levels of hydrogenation - strong, middle and the low ones. In order to interpret the experimental data, the imaginary part of the dielectric function was evaluated by means of Kramers-Kronig transformation. To determine quantitatively the influence of hydrogen atoms on the phonon and vibrational spectra of hydrogenated CdTe crystals we used the special statistical model proposed in this paper. This model takes into account the tetrahedron as the basic structural unit and distinguishes the contribution of the hydrogen bearing tetrahedra from the contribution of the hydrogen free ones to the crystal phonon spectra. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Report on the Radiation Effects Testing of the Infrared and Optical Transition Radiation Camera Systems

    Energy Technology Data Exchange (ETDEWEB)

    Holloway, Michael Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-20

    Presented in this report are the results tests performed at Argonne National Lab in collaboration with Los Alamos National Lab to assess the reliability of the critical 99Mo production facility beam monitoring diagnostics. The main components of the beam monitoring systems are two cameras that will be exposed to radiation during accelerator operation. The purpose of this test is to assess the reliability of the cameras and related optical components when exposed to operational radiation levels. Both X-ray and neutron radiation could potentially damage camera electronics as well as the optical components such as lenses and windows. This report covers results of the testing of component reliability when exposed to X-ray radiation. With the information from this study we provide recommendations for implementing protective measures for the camera systems in order to minimize the occurrence of radiation-induced failure within a ten month production run cycle.

  8. Probe And Enhancement Of SBS Based Phonons In Infrared Fibers Using Waveguide Coupled External Radiation

    Science.gov (United States)

    Yu, Chung; Chong, Yat C.; Fong, Chee K.

    1989-06-01

    Interaction of GHz and MHz radiation with CO2 laser propagation in a silver halide fiber using sBs based phonon coupling is furthet investigated. The external signal serves to both probe and enhance laser generated sBs phonons in the fiber. Efficient coupling of microwave radiation into the fiber is accomplished by placing the fiber in a hollow metallic waveguide, designed and constructed to transmit the dominant mode in the 0.9-2.0 GHz band. MHz radiation is conveniently coupled into the fiber using the guided microwave radiation as carrier. Phonon emissions from the fiber under CO2 laser pumping are first established on a spectrum analyzer; low frequency generators ale then tuned to match these frequencies and their maximum interaction recorded. Such interactions are systematically studied by monitoring the amplitude and waveform of the reflected and transmitted laser pulse at various power levels and frequencies of the externally coupled radiation. A plot of reflected laser power versus incident laser power reveals a distinct sBs generated phonon threshold. Variouslaunch directions of the GHz and MHz radiation with respect to the direction of laser propagation are realized to verify theory governing sBs interactions. The MHz radiation and its associated phonons in the fiber are convenient tools for probing sBs related phenomenon in infrared fibers.

  9. Radiation temperature measurement method for semitransparent materials using one-channel infrared pyrometer.

    Science.gov (United States)

    Fu, Tairan; Liu, Jiangfan; Zong, Anzhou

    2014-10-10

    Semitransparent zinc sulfide (ZnS) crystal materials are widely used as the infrared-transmitting windows for optical instruments operating in long wavelengths. This paper describes a temperature measurement method for high-temperature ZnS materials using the one-channel optical pyrometer based on a theoretical model of radiation transfer in semitransparent plates. Numerical analyses of the radiation properties of ZnS plate are used to optimize the spectral band for the optical pyrometry. The optimized measurement spectral band is based on a trade-off between the measurement radiation intensity and the signal-to-noise ratio (SNR) for the ZnS material. The effective waveband emittance of one-dimensional (1D) ZnS plates is analyzed for various experimental conditions (temperatures, thicknesses, and direction angles) for the one-channel infrared pyrometer with the optimized measurement spectral response. The analysis can be used to improve radiation temperature measurements of semitransparent ZnS materials in applications.

  10. The application of infrared synchrotron radiation to the study of interfacial vibrational modes

    Energy Technology Data Exchange (ETDEWEB)

    Hirschmugl, C.J.; Williams, G.P.

    1992-12-31

    Synchrotron radiation provides an extremely bright broad-band source in the infrared which is ideally suited to the study of surface and interface vibrational modes in the range 50--3,000 cm{sup {minus}1}. Thus it covers the important range of molecule-substrate interactions, as well as overlapping with the more easily accessible near-ir region where molecular internal modes are found. Compared to standard broadband infrared sources such as globars, not only is it 1,000 times brighter, but its emittance matches the phase-space of the electrochemical cell leading to full utilization of this brightness advantage. In addition, the source is more stable even than water-cooled globars in vacuum for both short-term and long-term fluctuations. The authors summarize the properties of synchrotron radiation in the infrared, in particular pointing out the distinct differences between this and the x-ray region. They use experimental data in discussing important issues of signal to noise and address the unique problems and advantages of the synchrotron source. Thus they emphasize the important considerations necessary for developing new facilities. This analysis then leads to a discussion of phase-space matching to electrochemical cells, and to other surfaces in vacuum. Finally they show several examples of the application of infrared synchrotron radiation to surface vibrational spectroscopy. The examples are for metal crystal surfaces in ultra-high vacuum and include CO/Cu(100) and (111) and CO/K/Cu(100). The experiments show how the stability of the synchrotron source allows subtle changes in the background to be observed in addition to the discrete vibrational modes. These changes are due to electronic states induced by the adsorbate. In some cases the authors have seen interferences between these and the discrete vibrational modes, leading to a breakdown of the dipole selection rules, and the observation of additional modes.

  11. The application of infrared synchrotron radiation to the study of interfacial vibrational modes

    Energy Technology Data Exchange (ETDEWEB)

    Hirschmugl, C.J.; Williams, G.P.

    1992-01-01

    Synchrotron radiation provides an extremely bright broad-band source in the infrared which is ideally suited to the study of surface and interface vibrational modes in the range 50--3,000 cm[sup [minus]1]. Thus it covers the important range of molecule-substrate interactions, as well as overlapping with the more easily accessible near-ir region where molecular internal modes are found. Compared to standard broadband infrared sources such as globars, not only is it 1,000 times brighter, but its emittance matches the phase-space of the electrochemical cell leading to full utilization of this brightness advantage. In addition, the source is more stable even than water-cooled globars in vacuum for both short-term and long-term fluctuations. The authors summarize the properties of synchrotron radiation in the infrared, in particular pointing out the distinct differences between this and the x-ray region. They use experimental data in discussing important issues of signal to noise and address the unique problems and advantages of the synchrotron source. Thus they emphasize the important considerations necessary for developing new facilities. This analysis then leads to a discussion of phase-space matching to electrochemical cells, and to other surfaces in vacuum. Finally they show several examples of the application of infrared synchrotron radiation to surface vibrational spectroscopy. The examples are for metal crystal surfaces in ultra-high vacuum and include CO/Cu(100) and (111) and CO/K/Cu(100). The experiments show how the stability of the synchrotron source allows subtle changes in the background to be observed in addition to the discrete vibrational modes. These changes are due to electronic states induced by the adsorbate. In some cases the authors have seen interferences between these and the discrete vibrational modes, leading to a breakdown of the dipole selection rules, and the observation of additional modes.

  12. Assessing Consistency in Radiated Thermal Output of Beef Steers by Infrared Thermography

    Directory of Open Access Journals (Sweden)

    Nigel Cook

    2016-07-01

    Full Text Available Measurements of radiated thermal output are claimed to reflect the metabolic efficiency of mammals. This is important in food-producing animals because a measure of metabolic efficiency may translate to desirable characteristics, such as growth efficiency or residual feed intake, and permit the grouping of animals by metabolic characteristics that can be more precisely managed. This study addresses the question of whether radiated thermal parameters are characteristic of individual animals under normal and metabolically-challenging conditions. Consistency in radiated thermal output was demonstrated over a period of four weeks on condition that a sufficiently representative sample of measurements could be made on individual animals. The study provided evidence that infrared thermography could be used as an automated, rapid, and reliable tool for assessing thermoregulatory processes.

  13. Infrared spectroscopy of radiation-chemical transformation of n-hexane on a beryllium surface

    Science.gov (United States)

    Gadzhieva, N. N.

    2017-07-01

    The radiation-chemical decomposition of n-hexane in a Be- n-hexane system under the effect of γ-irradiation at room temperature is studied by infrared reflection-absorption spectroscopy. In the absorbed dose range 5 kGy ≤ Vγ ≤ 50 kGy, intermediate surface products of radiation-heterogeneous decomposition of n-hexane (beryllium alkyls, π-olefin complexes, and beryllium hydrides) are detected. It is shown that complete radiolysis occurs at Vγ = 30 kGy; below this dose, decomposition of n-hexane occurs only partially, while higher doses lead to steady-state saturation. The radiation-chemical yield of the final decomposition product—molecular hydrogen—is determined to be G ads(H2) = 24.8 molecules/100 eV. A possible mechanism of this process is discussed.

  14. Long wavelength infrared radiation thermometry for non-contact temperature measurements in gas turbines

    Science.gov (United States)

    Manara, J.; Zipf, M.; Stark, T.; Arduini, M.; Ebert, H.-P.; Tutschke, A.; Hallam, A.; Hanspal, J.; Langley, M.; Hodge, D.; Hartmann, J.

    2017-01-01

    The objective of the EU project "Sensors Towards Advanced Monitoring and Control of Gas Turbine Engines (acronym STARGATE)" is the development of a suite of advanced sensors, instrumentation and related systems in order to contribute to the developing of the next generation of green and efficient gas turbine engines. One work package of the project deals with the design and development of a long wavelength infrared (LWIR) radiation thermometer for the non-contact measurement of the surface temperature of thermal barrier coatings (TBCs) during the operation of gas turbine engines. For opaque surfaces (e.g. metals or superalloys) radiation thermometers which are sensitive in the near or short wavelength infrared are used as state-of-the-art method for non-contact temperature measurements. But this is not suitable for oxide ceramic based TBCs (e.g. partially yttria stabilized zirconia) as oxide ceramics are semi-transparent in the near and short wavelength infrared spectral region. Fortunately the applied ceramic materials are non-transparent in the long wavelength infrared and additionally exhibit a high emittance in this wavelength region. Therefore, a LWIR pyrometer can be used for non-contact temperature measurements of the surfaces of TBCs as such pyrometers overcome the described limitation of existing techniques. For performing non-contact temperature measurements in gas turbines one has to know the infrared-optical properties of the applied TBCs as well as of the hot combustion gas in order to properly analyse the measurement data. For reaching a low uncertainty on the one hand the emittance of the TBC should be high (>0.9) in order to reduce reflections from the hot surrounding and on the other hand the absorbance of the hot combustion gas should be low (pyrometer and the selection of the optimal wavelength band where the detector should be sensitive. Besides determining the spectral infrared-optical properties (emittance, transmittance and absorbance) of the

  15. Efficacy and safety of far infrared radiation in lymphedema treatment: clinical evaluation and laboratory analysis.

    Science.gov (United States)

    Li, Ke; Zhang, Zheng; Liu, Ning Fei; Feng, Shao Qing; Tong, Yun; Zhang, Ju Fang; Constantinides, Joannis; Lazzeri, Davide; Grassetti, Luca; Nicoli, Fabio; Zhang, Yi Xin

    2017-04-01

    Swelling is the most common symptom of extremities lymphedema. Clinical evaluation and laboratory analysis were conducted after far infrared radiation (FIR) treatment on the main four components of lymphedema: fluid, fat, protein, and hyaluronan. Far infrared radiation is a kind of hyperthermia therapy with several and additional benefits as well as promoting microcirculation flow and improving collateral lymph circumfluence. Although FIR therapy has been applied for several years on thousands of lymphedema patients, there are still few studies that have reported the biological effects of FIR on lymphatic tissue. In this research, we investigate the effects of far infrared rays on the major components of lymphatic tissue. Then, we explore the effectiveness and safety of FIR as a promising treatment modality of lymphedema. A total of 32 patients affected by lymphedema in stage II and III were treated between January 2015 and January 2016 at our department. After therapy, a significant decrease of limb circumference measurements was noted and improving of quality of life was registered. Laboratory examination showed the treatment can also decrease the deposition of fluid, fat, hyaluronan, and protein, improving the swelling condition. We believe FIR treatment could be considered as both an alternative monotherapy and a useful adjunctive to the conservative or surgical lymphedema procedures. Furthermore, the real and significant biological effects of FIR represent possible future applications in wide range of the medical field.

  16. Infrared spectrophotometry and radiative transfer in optically thick circumstellar dust envelopes

    International Nuclear Information System (INIS)

    Merrill, K.M.

    1976-01-01

    The Two-Micron Sky Survey of Neugebauer and Leighton and, more recently, the AFCRL Infrared Sky Survey of Walker and Price have detected numerous compact, isolated, bright infrared sources which are not identified with previously cataloged stars. Observations of many such objects suggest that extensive circumstellar dust envelopes modify the flux from a central source. The present investigations employ broad bandpass photometry at lambda lambda 1.65 μm to 12.5 μm and narrow bandpass spectrophotometry (Δ lambda/lambda approximately 0.015) at lambda lambda 2-4 μm and lambda lambda 8-13 μm to determine the properties of a large sample of such infrared sources. Infrared spectrophotometry can clearly differentiate between normal stars of spectral types M(''oxygen-rich'') and C (''carbon-rich'') on the basis of characteristic absorption bands arising in cool stellar atmospheres. Most of the 2 μ Sky Survey and many of the AFCRL Sky Survey sources appear to be stars of spectral types M and C which are differentiated from normal cool comparison stars only by the presence of extensive circumstellar dust envelopes. Due to the large optical depth of the envelopes, the flux from the star and from the dust cannot be simply separated. Hence solutions of radiative transfer through spherically symmetric envelopes of arbitrary optical depth were generated by a generalized computer code which employed opacities of real dust

  17. Radiative Processes in Graphene and Similar Nanostructures in Strong Electric Fields

    Science.gov (United States)

    Gavrilov, S. P.; Gitman, D. M.

    2017-03-01

    Low-energy single-electron dynamics in graphene monolayers and similar nanostructures is described by the Dirac model, being a 2+1 dimensional version of massless QED with the speed of light replaced by the Fermi velocity vF ≃ c/300. Methods of strong-field QFT are relevant for the Dirac model, since any low-frequency electric field requires a nonperturbative treatment of massless carriers in the case it remains unchanged for a sufficiently long time interval. In this case, the effects of creation and annihilation of electron-hole pairs produced from vacuum by a slowly varying and small-gradient electric field are relevant, thereby substantially affecting the radiation pattern. For this reason, the standard QED text-book theory of photon emission cannot be of help. We construct the Fock-space representation of the Dirac model, which takes exact accounts of the effects of vacuum instability caused by external electric fields, and in which the interaction between electrons and photons is taken into account perturbatively, following the general theory (the generalized Furry representation). We consider the effective theory of photon emission in the first-order approximation and construct the corresponding total probabilities, taking into account the unitarity relation.

  18. An intelligent approach for cooling radiator fault diagnosis based on infrared thermal image processing technique

    International Nuclear Information System (INIS)

    Taheri-Garavand, Amin; Ahmadi, Hojjat; Omid, Mahmoud; Mohtasebi, Seyed Saeid; Mollazade, Kaveh; Russell Smith, Alan John; Carlomagno, Giovanni Maria

    2015-01-01

    This research presents a new intelligent fault diagnosis and condition monitoring system for classification of different conditions of cooling radiator using infrared thermal images. The system was adopted to classify six types of cooling radiator faults; radiator tubes blockage, radiator fins blockage, loose connection between fins and tubes, radiator door failure, coolant leakage, and normal conditions. The proposed system consists of several distinct procedures including thermal image acquisition, image pre-processing, image processing, two-dimensional discrete wavelet transform (2D-DWT), feature extraction, feature selection using a genetic algorithm (GA), and finally classification by artificial neural networks (ANNs). The 2D-DWT is implemented to decompose the thermal images. Subsequently, statistical texture features are extracted from the original images and are decomposed into thermal images. The significant selected features are used to enhance the performance of the designed ANN classifier for the 6 types of cooling radiator conditions (output layer) in the next stage. For the tested system, the input layer consisted of 16 neurons based on the feature selection operation. The best performance of ANN was obtained with a 16-6-6 topology. The classification results demonstrated that this system can be employed satisfactorily as an intelligent condition monitoring and fault diagnosis for a class of cooling radiator. - Highlights: • Intelligent fault diagnosis of cooling radiator using thermal image processing. • Thermal image processing in a multiscale representation structure by 2D-DWT. • Selection features based on a hybrid system that uses both GA and ANN. • Application of ANN as classifier. • Classification accuracy of fault detection up to 93.83%

  19. Tunable photonic crystal for THz radiation in layered superconductors: Strong magnetic-field dependence of the transmission coefficient

    International Nuclear Information System (INIS)

    Savel'ev, Sergey; Rakhmanov, A.L.; Nori, Franco

    2006-01-01

    Josephson plasma waves are scattered by the Josephson vortex lattice. This scattering results in a strong dependence, on the in-plane magnetic-field H ab , of the reflection and transmission of THz radiation propagating in layered superconductors. In particular, a tunable band-gap structure (THz photonic crystal) occurs in such a medium. These effects can be used, by varying H ab , for the selective frequency-filtering of THz radiation

  20. Diagnostics of ionization in air produced by infrared radiation from A pulse CO2 laser

    Science.gov (United States)

    Huston, E. S.

    This thesis begins with a brief account of the historical development of the modern concept of the atom and, building on this foundation, the physical principles responsible for the operation of a LASER are presented. A more detailed description is then given of the pulsed CO2 LASER used in this research, including principles of operation and safety procedures. Next, the research itself is described: an analysis of the ionization in air produced by focusing the LASER's infrared radiation. The data are summarized in graphs which map the region of ionization. Following conclusions on the research performed, specific suggestions are made for future work with the LASER.

  1. Atmospheric lifetimes, infrared absorption spectra, radiative forcings and global warming potentials of NF3 and CF3CF2Cl (CFC-115

    Directory of Open Access Journals (Sweden)

    A. Totterdill

    2016-09-01

    Full Text Available Fluorinated compounds such as NF3 and C2F5Cl (CFC-115 are characterised by very large global warming potentials (GWPs, which result from extremely long atmospheric lifetimes and strong infrared absorptions in the atmospheric window. In this study we have experimentally determined the infrared absorption cross sections of NF3 and CFC-115, calculated the radiative forcing and efficiency using two radiative transfer models and identified the effect of clouds and stratospheric adjustment. The infrared cross sections are within 10 % of previous measurements for CFC-115 but are found to be somewhat larger than previous estimates for NF3, leading to a radiative efficiency for NF3 that is 25 % larger than that quoted in the Intergovernmental Panel on Climate Change Fifth Assessment Report. A whole atmosphere chemistry–climate model was used to determine the atmospheric lifetimes of NF3 and CFC-115 to be (509 ± 21 years and (492 ± 22 years, respectively. The GWPs for NF3 are estimated to be 15 600, 19 700 and 19 700 over 20, 100 and 500 years, respectively. Similarly, the GWPs for CFC-115 are 6030, 7570 and 7480 over 20, 100 and 500 years, respectively.

  2. Status of the solar and infrared radiation submodels in the LLNL 1-D and 2-D chemical-transport models

    International Nuclear Information System (INIS)

    Grant, K.E.; Taylor, K.E.; Ellis, J.S.; Wuebbles, D.J.

    1987-07-01

    The authors have implemented a series of state of the art radiation transport submodels in previously developed one dimensional and two dimensional chemical transport models of the troposphere and stratosphere. These submodels provide the capability of calculating accurate solar and infrared heating rates. They are a firm basis for further radiation submodel development as well as for studying interactions between radiation and model dynamics under varying conditions of clear sky, clouds, and aerosols. 37 refs., 3 figs

  3. Dichroic filters to protect milliwatt far-infrared detectors from megawatt ECRH radiation.

    Science.gov (United States)

    Bertschinger, G; Endres, C P; Lewen, F; Oosterbeek, J W

    2008-10-01

    Dichroic filters have been used to shield effectively the far infrared (FIR) detectors at the interferometer/polarimeter on TEXTOR. The filters consist of metal foils with regular holes, the hole diameter, the mutual spacing and the thickness of the foils are chosen to transmit radiation at the design frequency with transmission >90%. The attenuation at the low frequency end of the bandpass filter is about 30 dB per octave, the high frequency transmission is between 20% and 40%. The filters have been used to block the stray radiation from the megawatt microwave heating beam to the detectors of the FIR interferometer, operating with power on the detector in the milliwatt range. If required, the low frequency attenuation can be still enhanced, without compromising the transmission in the passband. The FIR interferometer used for plasma density and position control is no longer disturbed by electromagnetic waves used for plasma heating.

  4. Towards strong light-matter coupling at the single-resonator level with sub-wavelength mid-infrared nano-antennas

    Energy Technology Data Exchange (ETDEWEB)

    Malerba, M.; De Angelis, F., E-mail: francesco.deangelis@iit.it [Istituto Italiano di Tecnologia, Via Morego, 30, I-16163 Genova (Italy); Ongarello, T.; Paulillo, B.; Manceau, J.-M.; Beaudoin, G.; Sagnes, I.; Colombelli, R., E-mail: raffaele.colombelli@u-psud.fr [Centre for Nanoscience and Nanotechnology (C2N Orsay), CNRS UMR9001, Univ. Paris Sud, Univ. Paris Saclay, 91405 Orsay (France)

    2016-07-11

    We report a crucial step towards single-object cavity electrodynamics in the mid-infrared spectral range using resonators that borrow functionalities from antennas. Room-temperature strong light-matter coupling is demonstrated in the mid-infrared between an intersubband transition and an extremely reduced number of sub-wavelength resonators. By exploiting 3D plasmonic nano-antennas featuring an out-of-plane geometry, we observed strong light-matter coupling in a very low number of resonators: only 16, more than 100 times better than what reported to date in this spectral range. The modal volume addressed by each nano-antenna is sub-wavelength-sized and it encompasses only ≈4400 electrons.

  5. Can the Infrared Radiation that Causes the Enhanced Greenhouse Effect Be Put to Better Use?

    Science.gov (United States)

    Zevenhoven, Ron

    2008-08-01

    Increasing levels of certain greenhouse gases (GHGs), most importantly CO2 in the earths atmosphere, lead to climate change and global warming as a result of these gases interacting with thermal infrared (TIR) radiation from earth to space. Here, the option of modifying this radiation is analyzed which would result in modified TIR radiation that would interact less with atmospheric CO2. This alleviates the enhanced greenhouse effect, and at the same time would allow for energy recovery as heat and/or power. Power production is, of course, limited by thermodynamics Second Law. It is shown that various options exist for TIR radiation modification which may be used to generate temperature gradients or temperature differences between volumes of (gases containing) CO2 of sufficient optical thickness. This may be further exploited for power generation: a first, simple case shows power generation of ˜1 W per m2 surface at a Carnot efficiency of ˜7%, using the sky and ground level surroundings as heat reservoirs.

  6. Infrared Radiative Properties of Yttria-Stabilized Zirconia Thermal Barrier Coatings

    Science.gov (United States)

    Eldridge, Jeff I.; Spuckler, Charles M.; Street, Ken W.; Markham, Jim R.; Gray, Hugh R. (Technical Monitor)

    2002-01-01

    The infrared (IR) transmittance and reflectance of translucent thermal barrier coatings (TBCs) have important implications for both the performance of these coatings as radiation barriers and emitters as well as affecting measurements of TBC thermal conductivity, especially as TBCs are being pushed to higher temperatures. In this paper, the infrared spectral directional-hemispherical transmittance and reflectance of plasma-sprayed 8wt% yttria-stabilized zirconia (8YSZ) TBCs are reported. These measurements are compared to those for single crystal YSZ specimens to show the effects of the plasma-sprayed coating microstructure. It is shown that the coatings exhibit negligible absorption at wavelengths up to about 5 micrometers, and that internal scattering rather than surface reflections dominates the hemispherical reflectance. The translucent nature of the 8YSZ TBCs results in the absorptance/emittance and reflectance of TBC-coated substrates depending on the TBC thickness, microstructure, as well as the radiative properties of the underlying substrate. The effects of these properties on TBC measurements and performance are discussed.

  7. Photoperiodic responses of Kalanchoe and chrysanthemum to radiation by an infrared lamp

    International Nuclear Information System (INIS)

    Ko, C.H.; Lee, S.B.; Jeong, B.R.

    2012-01-01

    This experiment was conducted to investigate the effect of a low intensity infrared radiation on the growth and photoperiodic responses of Kalanchoe blossfeldiana ‘Kaluna’ and ‘Taos’, and Dendranthema grandiflorum ‘Lemon Eye’ grown in growth chambers. In the first experiment, uniformly-rooted cuttings of ‘Kaluna’ and ‘Lemon Eye’ were selected and transplanted to 10 cm pots. After a week, pots were transferred from greenhouse to three environment-controlled growth chambers. All chambers were maintained at 25 ± 1 and 70% RH with an 8 hours photoperiod (760 μmol·m −2 ·s −1 ), provided by high pressure sodium and white fluorescent lamps. During the night period one chamber was left unlit (darkness), while the second and third ones were lit with an incandescent lamp (10 μmol·m −2 ·s −1 ) or an infrared lamp (15 μmol·m −2 ·s −1 ), respectively. Shoot length, root length, stem diameter, number of flowers, number of branches, fresh weight, and dry weight were measured after eight weeks. Flowering occurred on plants maintained in the unlit darkness and under an incandescent lamp during the night period, while only vegetative growth was observed under an infrared lamp. In the second experiment, cuttings of uniformly-rooted ‘Taos’ and ‘Lemon Eye’ were selected and transferred from the greenhouse to three environment-controlled growth chambers with the same environment setting as in the first experiment at a week after potting. During the night period one chamber was left unlit (darkness), the second and third ones were lit with an incandescent or an infrared heating lamp, both at a 0.3 μmol·m −2 ·s −1 PPFD level. After nine weeks, flowering in all treatments was observed, but was slightly delayed under an incandescent and an infrared heating lamp. Because both the incandescent lamp and the infrared lamp slightly delayed flowering in these two species, a more detailed experiment is necessary to find out at which

  8. Strong spin-phonon coupling in infrared and Raman spectra of SrMnO.sub.3./sub..

    Czech Academy of Sciences Publication Activity Database

    Kamba, Stanislav; Goian, Veronica; Skoromets, Volodymyr; Hejtmánek, Jiří; Bovtun, Viktor; Kempa, Martin; Borodavka, Fedir; Vaněk, Přemysl; Belik, A.A.; Lee, J.H.; Pacherová, Oliva; Rabe, K.M.

    2014-01-01

    Roč. 89, č. 6 (2014), "064308-1"-"064308-9" ISSN 1098-0121 R&D Projects: GA MŠk LH13048; GA ČR GAP204/12/1163; GA MŠk LD12026; GA ČR GP14-14122P Institutional support: RVO:68378271 Keywords : multiferroics * spin-phonon coupling * infrared and Raman spectra Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.736, year: 2014

  9. A Broad-Area Method for the Diurnal Characterisation of Upwelling Medium Wave Infrared Radiation

    Directory of Open Access Journals (Sweden)

    Bryan Hally

    2017-02-01

    Full Text Available Fire detection from satellite sensors relies on an accurate estimation of the unperturbed state of a target pixel, from which an anomaly can be isolated. Methods for estimating the radiation budget of a pixel without fire depend upon training data derived from the location’s recent history of brightness temperature variation over the diurnal cycle, which can be vulnerable to cloud contamination and the effects of weather. This study proposes a new method that utilises the common solar budget found at a given latitude in conjunction with an area’s local solar time to aggregate a broad-area training dataset, which can be used to model the expected diurnal temperature cycle of a location. This training data is then used in a temperature fitting process with the measured brightness temperatures in a pixel, and compared to pixel-derived training data and contextual methods of background temperature determination. Results of this study show similar accuracy between clear-sky medium wave infrared upwelling radiation and the diurnal temperature cycle estimation compared to previous methods, with demonstrable improvements in processing time and training data availability. This method can be used in conjunction with brightness temperature thresholds to provide a baseline for upwelling radiation, from which positive thermal anomalies such as fire can be isolated.

  10. In vitro effects of infrared A radiation on the synthesis of MMP-1, catalase, superoxide dismutase and GADD45 alpha protein.

    Science.gov (United States)

    Costa, Adilson; Eberlin, Samara; Clerici, Stefano P; Abdalla, Beatrice M Z

    2015-01-01

    Harmful influences in the process of photoaging and skin damage are associated with infrared A (IRA) radiation, such as, disturbance of dermal extracellular matrix by up regulation of matrix metalloproteinase-1 (MMP1). Furthermore, DNA damage, induction of cytotoxicity and oxidative stress by decreasing natural antioxidant ability has been reported after acute exposure to IRA. The present study provides additional evidence that IRA radiation response in human skin fibroblasts produces deleterious effects to the cell, such as accelerating aging and weakening of their antioxidant defense mechanism. Human skin fibroblasts were exposed to a non-cytotoxic dose of IRA radiation and cultured for different periods for further collection of cell-free supernatants and lysates, and quantification of MMP-1, catalase, superoxide dismutase, and GADD45a. Our results corroborate previous published data and strongly indicate a negative impact of IRA radiation on the skin physiological by mechanisms involving reduced endogenous antioxidant enzymatic defense, increased MMP-1 and decreased repair process of DNA by reducing GADD45a protein, in cultured human fibroblasts. From a clinical perspective, IRA radiation acts by mechanisms distinct from those observed in ultraviolet radiation indicating the need for developing and making available cosmetics for skin care with properties beyond protection exerted by traditional sunscreens.

  11. Oxidation of arsenite by molecular oxygen in strong alkaline solution under γ-radiation

    International Nuclear Information System (INIS)

    Burkitbaev, M.M.

    1996-01-01

    The kinetics and mechanism of radiation-stimulated process in 1 mole/1 l of potassium hydroxide have been studied. Radiation chemical yield of (G(As)(Y)) oxygenation grows directly proportionally to oxygen concentration and inversely proportionally to dose rate in proportion 1/2. Mechanism of oxidation, including two chain cycles (long chain cycle - with participation of O - ; O 2 - ; O 3 - radicals and short chain one -with participation of arsenic contenting radicals: As(IV), As(IV)O, As(IV)O 2 ) is proposed. (author)

  12. Development of a fogless scope and its analysis using infrared radiation pyrometer.

    Science.gov (United States)

    Hashimoto, D; Shouji, M

    1997-08-01

    In laparoscopic surgery, fogging of the lens tip instantly degrades the quality of image and interrupts the flow of surgical maneuvers. External warming devices prevent fogging for a certain length of time, but use of them is troublesome at best. These problems prompted us to develop a fogless mechanism built into the scope so that the fogless image would be continuous and trouble-free. We then conducted several experiments that demonstrate the precise effect it has on the lens tip. The infrared radiation pyrometer was used to compare the temperature distribution as well as the temperature change against time of each lens tip of the fogless and ordinary laparoscopes. The temperature of the lens tip of the ordinary scope did not change, but that of the fogless scope rose to 41 degrees C in 184-208 s. The fogless mechanism effectively warms the lens tip to a safe temperature that prevents fogging in the intraabdominal environment.

  13. Cis- and trans-perfluorodecalin: Infrared spectra, radiative efficiency and global warming potential

    Science.gov (United States)

    Le Bris, Karine; DeZeeuw, Jasmine; Godin, Paul J.; Strong, Kimberly

    2017-12-01

    Perfluorodecalin (PFD) is a molecule used in various medical applications for its capacity to dissolve gases. This potent greenhouse gas was detected for the first time in the atmosphere in 2005. We present infrared absorption cross-section spectra of a pure vapour of cis- and trans-perfluorodecalin at a resolution of 0.1 cm-1. Measurements were performed in the 560-3000 cm-1 spectral range using Fourier transform spectroscopy. The spectra have been compared with previous experimental data and theoretical calculations by density functional theory. The new experimental absorption cross-sections have been used to calculate a lifetime-corrected radiative efficiency at 300 K of 0.62 W m-2 ppb-1 and 0.57 W.m-2.ppb-1 for the cis and trans isomers respectively. This leads to a 100-year time horizon global warming potential of 8030 for cis-PFD and 7440 for trans-PFD.

  14. Effect of Infrared Radiation on the Healing of Diabetic Foot Ulcer.

    Science.gov (United States)

    Hakim, Ashrafalsadat; Sadeghi Moghadam, Ali; Shariati, Abdalali; Karimi, Hamid; Haghighizadeh, Mohamad Hossien

    2016-07-01

    Diabetic foot ulcer is a worldwide health care concern affecting tens of thousands of patients. If these ulcers left untreated, they can create severe complications. This study was designed to examine the effect of infrared radiation on the healing of diabetic foot ulcer. This clinical trial was performed on 50 patients referred to Dr. Ganjavian hospital in Dezful city, Iran, with diabetic foot ulcer degree 1 and 2 (based on Wegener Scale). Sample size was determined based on relevant studies of the recent decade. Patients were classified into the intervention and control groups (n = 25 in each group) in terms of age, gender, degree of ulcer, ulcer site and body mass index. In this study, work progress was evaluated according to the checklist of diabetic foot ulcer healing evaluation. The results of the current study showed that there was a statistically significant difference in healing ulcers (P < 0.05) and mean healing time (P < 0.05) between the two groups. Using the infrared plus routine dressing is more effective than using merely routine dressing.

  15. Coatings manufactured using magnetron sputtering technology to protect against infrared radiation for use in firefighter helmets

    Directory of Open Access Journals (Sweden)

    Fejdyś Marzena

    2016-09-01

    Full Text Available The aim of this study was to test the usefulness of magnetron sputtering technology to produce coatings on selected elements of a firefighter’s helmet to protect against infrared radiation (PN-EN 171 standard. The scope of research includes testing the deposition produced via magnetron sputtering of metallic and ceramic coatings on plastics, which are used to manufacture the components comprising the personal protection equipment used by firefighters. The UV-VIS, NIR used to research the permeation coefficients and reflections for light and infrared light and the emission spectrometry with ICP-AES used for the quantitative analysis of elements in metallic and ceramic coatings. Microstructural and micro-analytical testing of the coatings were performed using scanning electron microscopy (SEM. Measurements of the chemical compositions were conducted using energy-dispersive X-ray spectroscopy (EDS. The hardnesss of the coatings were tested using a indentation method, and the coating thicknesses were tested using a ellipsometry method.

  16. A strong adaptable autofocusing approach of off-axis infrared digital holography under different quality conditions of holograms

    Science.gov (United States)

    Liu, Ning; Yang, Chao

    2017-01-01

    In this paper, we present an innovative autofocusing criterion for the reconstruction of infrared digital holograms. This criterion has the advantages of fast, efficient and precision when determining the reconstruction distance of off-axis digital holography. This criterion is a mean-free high frequency calculation process. We focus on the problem of mean value drifting found in previous published methods and design our new approach to solve it. Unlike the previous methods perform well only with high quality holograms, our method is effective for both high and low quality holograms. Even when hologram is degraded by destructive interference, our method still performs well. This method helps to automatically determine the precise reconstruction distance, and we are sure that this technology can be applied in industrial applications in the future.

  17. 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.

  18. Effects of water vapour on the structure parameter of the refractive index for near-infrared radiation

    NARCIS (Netherlands)

    Moene, A.F.

    2003-01-01

    The refractive index of air (n) mainly depends on temperature and water vapour content. For near-infrared radiation, temperature is the main determining factor. To determine the structure parameter of temperature (C-T(2)) from the structure parameter of the refractive index (C-n(2)), the influence

  19. Generation of infrared supercontinuum radiation: spatial mode dispersion and higher-order mode propagation in ZBLAN step-index fibers

    DEFF Research Database (Denmark)

    Ramsay, Jacob Søndergaard; Dupont, Sune Vestergaard Lund; Johansen, Mikkel Willum

    2013-01-01

    Using femtosecond upconversion we investigate the time and wavelength structure of infrared supercontinuum generation. It is shown that radiation is scattered into higher order spatial modes (HOMs) when generating a supercontinuum using fibers that are not single-moded, such as a step-index ZBLAN...... not include scattering into HOMs, and including this provides an extra degree of freedom for tailoring supercontinuum sources....

  20. The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 1: Setup, uncertainty analysis, and assessment of far-infrared water vapor continuum

    Directory of Open Access Journals (Sweden)

    R. Sussmann

    2016-09-01

    Full Text Available Quantitative knowledge of water vapor radiative processes in the atmosphere throughout the terrestrial and solar infrared spectrum is still incomplete even though this is crucial input to the radiation codes forming the core of both remote sensing methods and climate simulations. Beside laboratory spectroscopy, ground-based remote sensing field studies in the context of so-called radiative closure experiments are a powerful approach because this is the only way to quantify water absorption under cold atmospheric conditions. For this purpose, we have set up at the Zugspitze (47.42° N, 10.98° E; 2964 m a.s.l. a long-term radiative closure experiment designed to cover the infrared spectrum between 400 and 7800 cm−1 (1.28–25 µm. As a benefit for such experiments, the atmospheric states at the Zugspitze frequently comprise very low integrated water vapor (IWV; minimum  =  0.1 mm, median  =  2.3 mm and very low aerosol optical depth (AOD  =  0.0024–0.0032 at 7800 cm−1 at air mass 1. All instruments for radiance measurements and atmospheric-state measurements are described along with their measurement uncertainties. Based on all parameter uncertainties and the corresponding radiance Jacobians, a systematic residual radiance uncertainty budget has been set up to characterize the sensitivity of the radiative closure over the whole infrared spectral range. The dominant uncertainty contribution in the spectral windows used for far-infrared (FIR continuum quantification is from IWV uncertainties, while T profile uncertainties dominate in the mid-infrared (MIR. Uncertainty contributions to near-infrared (NIR radiance residuals are dominated by water vapor line parameters in the vicinity of the strong water vapor bands. The window regions in between these bands are dominated by solar Fourier transform infrared (FTIR calibration uncertainties at low NIR wavenumbers, while uncertainties due to AOD become an

  1. Antibacterial effect of citrus press-cakes dried by high speed and far-infrared radiation drying methods

    Science.gov (United States)

    Samarakoon, Kalpa; Senevirathne, Mahinda; Lee, Won-Woo; Kim, Young-Tae; Kim, Jae-Il; Oh, Myung-Cheol

    2012-01-01

    In this study, the antibacterial effect was evaluated to determine the benefits of high speed drying (HSD) and far-infrared radiation drying (FIR) compared to the freeze drying (FD) method. Citrus press-cakes (CPCs) are released as a by-product in the citrus processing industry. Previous studies have shown that the HSD and FIR drying methods are much more economical for drying time and mass drying than those of FD, even though FD is the most qualified drying method. The disk diffusion assay was conducted, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined with methanol extracts of the dried CPCs against 11 fish and five food-related pathogenic bacteria. The disk diffusion results indicated that the CPCs dried by HSD, FIR, and FD prevented growth of all tested bacteria almost identically. The MIC and MBC results showed a range from 0.5-8.0 mg/mL and 1.0-16.0 mg/mL respectively. Scanning electron microscopy indicated that the extracts changed the morphology of the bacteria cell wall, leading to destruction. These results suggest that CPCs dried by HSD and FIR showed strong antibacterial activity against pathogenic bacteria and are more useful drying methods than that of the classic FD method in CPCs utilization. PMID:22808341

  2. Combined Effect of Infrared and Gamma Radiation on Certain Insects in Stored Wheat Grains and Wheat Flour *

    International Nuclear Information System (INIS)

    Mohamed, S.A.; Mikhaiel, A.A.

    2013-01-01

    Dosage mortality studies on the infrared radiation and combined effects with 1500 Gy gamma irradiation, which calculated to kill about 50% of adults, were applied to samples of 50 and 100 grams of wheat grains and flour containing newly emerged adults of T. granarium, T. castaneum, S. granarius and R. dominica. The time required to obtain thermal energy from infrared radiation that were lethal to those adults depends not only on the insect species but also on the heat retention characteristics of the grain or flour and the distances from source of radiation to materials. The dose of infrared (180 sec) at which the temperature attained to 64.8 degree C and 54.3 degree C on 50 and 100 g of wheat flour gave about 60.0 and 44.67% adult mortality for T. granarium and 58.67% and 39.33% adult mortality for T. castaneum on distance 4 cm, respectively. The combined gamma radiation (1500 Gy) with the same doses of infrared gave 96.0% and 86.0%, 90.0% and 78.0% adult mortalities for T. granarium and T. castaneum, respectively. At dose 240 sec infrared on 50 and 100 g of wheat grains which received 77 degree C and 69.7 degree C gave about 60.0% and 46.0% adult mortality for S. granarius and 56.67% and 42.67% for R. dominica on distance 4 cm, respectively, but the combination of 1500 Gy with the same dose of infrared gave 98.0% and 90.0% adult mortality for S. granarius and 94.0% and 88.0% adult mortality for R. dominica, respectively. By rising the time of exposure and reducing distance from IR source, the temperatures were gradually increased causing high adult mortalities. Finally, T. granarium, T. castaneum, and S. granarius were more sensitive than R. dominica.

  3. Radiative heat transfer in strongly forward scattering media of circulating fluidized bed combustors

    Science.gov (United States)

    Ates, Cihan; Ozen, Guzide; Selçuk, Nevin; Kulah, Gorkem

    2016-10-01

    Investigation of the effect of particle scattering on radiative incident heat fluxes and source terms is carried out in the dilute zone of the lignite-fired 150 kWt Middle East Technical University Circulating Fluidized Bed Combustor (METU CFBC) test rig. The dilute zone is treated as an axisymmetric cylindrical enclosure containing grey/non-grey, absorbing, emitting gas with absorbing, emitting non/isotropically/anisotropically scattering particles surrounded by grey diffuse walls. A two-dimensional axisymmetric radiation model based on Method of Lines (MOL) solution of Discrete Ordinates Method (DOM) coupled with Grey Gas (GG)/Spectral Line-Based Weighted Sum of Grey Gases Model (SLW) and Mie theory/geometric optics approximation (GOA) is extended for incorporation of anisotropic scattering by using normalized Henyey-Greenstein (HG)/transport approximation for the phase function. Input data for the radiation model is obtained from predictions of a comprehensive model previously developed and benchmarked against measurements on the same CFBC burning low calorific value indigenous lignite with high volatile matter/fixed carbon (VM/FC) ratio in its own ash. Predictive accuracy and computational efficiency of nonscattering, isotropic scattering and forward scattering with transport approximation are tested by comparing their predictions with those of forward scattering with HG. GG and GOA based on reflectivity with angular dependency are found to be accurate and CPU efficient. Comparisons reveal that isotropic assumption leads to under-prediction of both incident heat fluxes and source terms for which discrepancy is much larger. On the other hand, predictions obtained by neglecting scattering were found to be in favorable agreement with those of forward scattering at significantly less CPU time. Transport approximation is as accurate and CPU efficient as HG. These findings indicate that negligence of scattering is a more practical choice in solution of the radiative

  4. Infrared Radiation Assisted Stokes’ Law Based Synthesis and Optical Characterization of ZnS Nanoparticles

    Directory of Open Access Journals (Sweden)

    Beer Pal Singh

    2016-01-01

    Full Text Available The strategy and technique exploited in the synthesis of nanostructure materials have an explicit effect on the nucleation, growth, and properties of product materials. Nanoparticles of zinc sulfide (ZnS have been synthesized by new infrared radiation (IR assisted and Stokes’ law based controlled bottom-up approach without using any capping agent and stirring. IR has been used for heating the reaction surface designed in accordance with the well-known Stokes law for a free body falling in a quiescent fluid for the synthesis of ZnS nanoparticles. The desired concentration of aqueous solutions of zinc nitrate (Zn(NO32·4H2O and thioacetamide (CH3CSNH2 was reacted in a controlled manner by IR radiation heating at the reaction area (top layer of reactants solution of the solution which results in the formation of ZnS nanoparticles at ambient conditions following Stokes’ law for a free body falling in a quiescent fluid. The phase, crystal structure, and particle size of as-synthesized nanoparticles were studied by X-ray diffraction (XRD. The optical properties of as-synthesized ZnS nanoparticles were studied by means of optical absorption spectroscopic measurements. The optical energy band gap and the nature of transition have been studied using the well-known Tauc relation with the help of absorption spectra of as-synthesized ZnS nanoparticles.

  5. Fourier Transform Infrared Radiation Spectroscopy Applied for Wood Rot Decay and Mould Fungi Growth Detection

    Directory of Open Access Journals (Sweden)

    Bjørn Petter Jelle

    2012-01-01

    Full Text Available Material characterization may be carried out by the attenuated total reflectance (ATR Fourier transform infrared (FTIR radiation spectroscopical technique, which represents a powerful experimental tool. The ATR technique may be applied on both solid state materials, liquids, and gases with none or only minor sample preparations, also including materials which are nontransparent to IR radiation. This facilitation is made possible by pressing the sample directly onto various crystals, for example, diamond, with high refractive indices, in a special reflectance setup. Thus ATR saves time and enables the study of materials in a pristine condition, that is, the comprehensive sample preparation by pressing thin KBr pellets in traditional FTIR transmittance spectroscopy is hence avoided. Materials and their ageing processes, both ageing by natural and accelerated climate exposure, decomposition and formation of chemical bonds and products, may be studied in an ATR-FTIR analysis. In this work, the ATR-FTIR technique is utilized to detect wood rot decay and mould fungi growth on various building material substrates. An experimental challenge and aim is to be able to detect the wood rot decay and mould fungi growth at early stages when it is barely visible to the naked eye. Another goal is to be able to distinguish between various species of fungi and wood rot.

  6. Infrared light-emitting diode radiation causes gravitropic and morphological effects in dark-grown oat seedlings

    Science.gov (United States)

    Johnson, C. F.; Brown, C. S.; Wheeler, R. M.; Sager, J. C.; Chapman, D. K.; Deitzer, G. F.

    1996-01-01

    Oat (Avena sativa cv Seger) seedlings were irradiated with IR light-emitting diode (LED) radiation passed through a visible-light-blocking filter. Infrared LED irradiated seedlings exhibited differences in growth and gravitropic response when compared to seedlings grown in darkness at the same temperature. Thus, the oat seedlings in this study were able to detect IR LED radiation. These findings call into question the use of IR LED as a safe-light for some photosensitive plant response experiments. These findings also expand the defined range of wavelengths involved in radiation-gravity (light-gravity) interactions to include wavelengths in the IR region of the spectrum.

  7. Disease quantification in dermatology: in vivo near-infrared spectroscopy measures correlate strongly with the clinical assessment of psoriasis severity

    Science.gov (United States)

    Greve, Tanja Maria; Kamp, Søren; Jemec, Gregor B. E.

    2013-03-01

    Accurate documentation of disease severity is a prerequisite for clinical research and the practice of evidence-based medicine. The quantification of skin diseases such as psoriasis currently relies heavily on clinical scores. Although these clinical scoring methods are well established and very useful in quantifying disease severity, they require an extensive clinical experience and carry a risk of subjectivity. We explore the opportunity to use in vivo near-infrared (NIR) spectra as an objective and noninvasive method for local disease severity assessment in 31 psoriasis patients in whom selected plaques were scored clinically. A partial least squares (PLS) regression model was used to analyze and predict the severity scores on the NIR spectra of psoriatic and uninvolved skin. The correlation between predicted and clinically assigned scores was R=0.94 (RMSE=0.96), suggesting that in vivo NIR provides accurate clinical quantification of psoriatic plaques. Hence, NIR may be a practical solution to clinical severity assessment of psoriasis, providing a continuous, linear, numerical value of severity.

  8. Temperature changes in contact lenses in connection with radiation from infrared heaters.

    Science.gov (United States)

    Lövsund, P; Nilsson, S E; Oberg, P A

    1979-09-01

    A number of reports have appeared over the past few years with warnings about the wearing of contact lenses in certain trades involving exposure to are flash. In view of these reports and in light of knowledge on the marked absorption by contact lenses, within the infrared (IR) region, temperature changes were measured in soft contact lenses under radiation from IR heaters used, for example, in the motor industry for drying paint. The lenses were tested while free-hanging and when applied to rabbit eyes. Great increases in temperature were noted with one of the heaters at a distance corresponding to "safe." During 10 min of exposure the temperature of a free-hanging lens rose from 21 to 59 degrees C, whereas the temperature in the surrounding air increased only from 26 to 30 degrees C. The final temperature of the lens was thus 29 degrees C higher than that of the air. In lenses applied to rabbit eyes the temperature rose within only 0.5, 1.0, and 1.5 min from approximately 33 degrees C to about 44, 49, and 51 degrees C, respectively; the air temperature rose from 25 to only 28 degrees C. In other words, the ultimate lens temperature was 23 degrees C higher than the ambient air temperature. In the rabbit experiments most of the lenses dried out completely. There would thus seem to be considerable risk of contact lenses drying and becoming adherent to and damaging the corneal surface among workers exposed to powerful radiation from IR radiators (IR heaters), unless they use efficient eye protectors. IR heaters appear to be associated with greater hazards than are flashes, since there is no warning from powerful visible light and because they are capable of causing a very rapid increase in temperature.

  9. The impact of infrared radiation in flight control in the Australian "firebeetle" Merimna atrata.

    Directory of Open Access Journals (Sweden)

    Marcel Hinz

    Full Text Available Infrared (IR receptors are rare in insects and have only been found in the small group of so-called pyrophilous insects, which approach forest fires. In previous work the morphology of the IR receptors and the physiology of the inherent sensory cells have been investigated. It was shown that receptors are located on the thorax and the abdomen respectively and show an astounding diversity with respect to structure and the presumed transduction mechanism. What is completely missing, however, is any behavioral evidence for the function of the IR receptors in pyrophilous insects. Here we describe the responses of the Australian "firebeetle", Merimna atrata to IR radiation. Beetles in a restrained flight were laterally stimulated with IR radiation of an intensity 20% above a previously determined electrophysiological threshold of the IR organs (40 mW/cm2. After exposure, beetles always showed an avoidance response away from the IR source. Reversible ablation experiments showed that the abdominal IR receptors are essential for the observed behavior. Tests with weaker IR radiation (11.4 mW/cm2 also induced avoidance reactions in some beetles pointing to a lower threshold. In contrast, beetles were never attracted by the IR source. Our results suggest that the IR receptors in Merimna atrata serve as an early warning system preventing an accidental landing on a hot surface. We also tested if another fire specific stimulus, the view of a large smoke plume, influenced the flight. However, due to an unexpected insensitivity of the flying beetles to most visual stimuli results were ambiguous.

  10. Strong relationship between DMS and the solar radiation dose over the global surface ocean.

    Science.gov (United States)

    Vallina, Sergio M; Simó, Rafel

    2007-01-26

    Marine biogenic dimethylsulfide (DMS) is the main natural source of tropospheric sulfur, which may play a key role in cloud formation and albedo over the remote ocean. Through a global data analysis, we found that DMS concentrations are highly positively correlated with the solar radiation dose in the upper mixed layer of the open ocean, irrespective of latitude, plankton biomass, or temperature. This is a necessary condition for the feasibility of a negative feedback in which light-attenuating DMS emissions are in turn driven by the light dose received by the pelagic ecosystem.

  11. Enhanced ULF radiation observed by DEMETER two months around the strong 2010 Haiti earthquake

    Directory of Open Access Journals (Sweden)

    M. A. Athanasiou

    2011-04-01

    Full Text Available In this paper we study the energy of ULF electromagnetic waves that were recorded by the satellite DEMETER, during its passing over Haiti before and after a destructive earthquake. This earthquake occurred on 12 January 2010, at geographic Latitude 18.46° and Longitude 287.47°, with Magnitude 7.0 R. Specifically, we are focusing on the variations of energy of Ez-electric field component concerning a time period of 100 days before and 50 days after the strong earthquake. In order to study these variations, we have developed a novel method that can be divided in two stages: first we filter the signal, keeping only the ultra low frequencies and afterwards we eliminate its trend using techniques of Singular Spectrum Analysis (SSA, combined with a third-degree polynomial filter. As it is shown, a significant increase in energy is observed for the time interval of 30 days before the earthquake. This result clearly indicates that the change in the energy of ULF electromagnetic waves could be related to strong precursory earthquake phenomena. Moreover, changes in energy associated with strong aftershock activity were also observed 25 days after the earthquake. Finally, we present results concerning the comparison between changes in energy during night and day passes of the satellite over Haiti, which showed differences in the mean energy values, but similar results as far as the rate of the energy change is concerned.

  12. Nonlinear response of the quantum Hall system to a strong electromagnetic radiation

    International Nuclear Information System (INIS)

    Avetissian, H.K.; Mkrtchian, G.F.

    2016-01-01

    We study nonlinear response of a quantum Hall system in semiconductor-hetero-structures via third harmonic generation process and nonlinear Faraday effect. We demonstrate that Faraday rotation angle and third harmonic radiation intensity have a characteristic Hall plateaus feature. These nonlinear effects remain robust against the significant broadening of Landau levels. We predict realization of an experiment through the observation of the third harmonic signal and Faraday rotation angle, which are within the experimental feasibility. - Highlights: • Nonlinear optical response of a quantum Hall system has specific plateaus feature. • This effect remains robust against the significant broadening of Landau levels. • It can be observed via the third harmonic signal and the nonlinear Faraday effect.

  13. Analysis of the construction of the high-temperature gas infrared radiator with the use of virtual prototyping

    Directory of Open Access Journals (Sweden)

    Ermolaev Anton N.

    2017-01-01

    Full Text Available Method of virtual prototyping with the following mathematical modeling was used to simulate the heat-mass exchange and combustion during the operation of high-temperature gas infrared radiators, and to find optimal technical solutions for its design. The most authoritative and approved software product Ansys Multiphysics was used. The results of the mathematical modeling of heat and mass transfer in a turbulent reaction medium with combustion reproduce the experimental data produced by a measurement in real operating conditions of the gas-fired infrared heat emitter. The temperature distribution along the height of the ceramic nozzle was established. Obtained results enable estimation of the ignition and combustion zones.

  14. Search for the Supersymmetric Partner to the Top Quark Using Recoils Against Strong Initial State Radiation

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00375257

    The ATLAS experiment at Large Hadron Collider (LHC) searches for experimental evidence of beyond the standard model physics at the TeV scale. As we collect more data at the LHC we continue to extend our sensitivity to these new phenomena, probing for the existence of increasingly massive particles. Despite this progress there are still regions of parameter space where constraints remain weak. One common region where we lack sensitivity is when the new BSM particle has a very small mass splitting between it and its decay products. The BSM particle then has little energy left over to give momenta to its decay products and the low momenta decay products are difficult to experimentally detect. These regions of small mass splitting are called compressed regions. We are able to gain sensitivity to these difficult regions by searching for new particles produced in conjunction with hard initial state radiation (ISR). The hard ISR boosts the new particle’s decay products and gives them momentum. This thesis covers t...

  15. Hawking radiation from small black holes at strong coupling and large N

    Science.gov (United States)

    Haddad, Nidal

    2013-10-01

    In a previous work an approximate static metric was found of a test black string that stretches from the boundary to the horizon of the planar Schwarzschild-AdS5 geometry. This is the gravity dual of the Unruh state for {N}=4, SU(N) super Yang-Mills theory on a four-dimensional Schwarzschild background, at large N and large ’tHooft coupling. We compute the holographic stress tensor of the gravitational solution and it turns out to possess many essential features of the Unruh state for weakly coupled Hawking radiation, such as the appearance of a negative energy density near the black hole horizon and a positive energy density at infinity. It also confirms recent results that at leading order in N, the expectation value of the stress tensor in the Unruh state is finite on both the future and past horizons, and that at this order there are no flux terms as is expected in the black droplet phase.

  16. Near-Infrared Transcranial Radiation for Major Depressive Disorder: Proof of Concept Study.

    Science.gov (United States)

    Cassano, Paolo; Cusin, Cristina; Mischoulon, David; Hamblin, Michael R; De Taboada, Luis; Pisoni, Angela; Chang, Trina; Yeung, Albert; Ionescu, Dawn F; Petrie, Samuel R; Nierenberg, Andrew A; Fava, Maurizio; Iosifescu, Dan V

    2015-01-01

    Transcranial near-infrared radiation (NIR) is an innovative treatment for major depressive disorder (MDD), but clinical evidence for its efficacy is limited. Our objective was to investigate the tolerability and efficacy of NIR in patients with MDD. We conducted a proof of concept, prospective, double-blind, randomized study of 6 sessions of NIR versus sham treatment for patients with MDD, using a crossover design. Four patients with MDD with mean age 47 ± 14 (SD) years (1 woman and 3 men) were exposed to irradiance of 700 mW/cm(2) and a fluence of 84 J/cm(2) for a total NIR energy of 2.40 kJ delivered per session for 6 sessions. Baseline mean HAM-D17 scores decreased from 19.8 ± 4.4 (SD) to 13 ± 5.35 (SD) after treatment (t = 7.905; df = 3; P = 0.004). Patients tolerated the treatment well without any serious adverse events. These findings confirm and extend the preliminary data on NIR as a novel intervention for patients with MDD, but further clinical trials are needed to better understand the efficacy of this new treatment. This trial is registered with ClinicalTrials.gov NCT01538199.

  17. Plasmonic Glasses and Films Based on Alternative Inexpensive Materials for Blocking Infrared Radiation.

    Science.gov (United States)

    V Besteiro, Lucas; Kong, Xiang-Tian; Wang, Zhiming; Rosei, Federico; Govorov, Alexander O

    2018-04-16

    The need for energy-saving materials is pressing. This Letter reports on the design of energy-saving glasses and films based on plasmonic nanocrystals that efficiently block infrared radiation. Designing such plasmonic composite glasses is nontrivial and requires taking full advantage of both material and geometrical properties of the nanoparticles. We compute the performance of solar plasmonic glasses incorporating a transparent matrix and specially shaped nanocrystals. This performance depends on the shape and material of such nanocrystals. Glasses designed with plasmonic nanoshells are shown to exhibit overall better performances as compared to nanorods and nanocups. Simultaneously, scalable synthesis of plasmonic nanoshells and nanocups is technologically feasible using gas-phase fabrication methods. The computational simulations were performed for noble metals (gold and silver) as well as for alternative plasmonic materials (aluminum, copper, and titanium nitride). Inexpensive plasmonic materials (silver, copper, aluminum, and titanium nitride) show an overall good performance in terms of the commonly used figures of merit of industrial glass windows. Together with numerical data for specific materials, this study includes a set of general rules for designing efficient plasmonic IR-blocking media. The plasmonic glasses proposed herein are good candidates for the creation of cheap optical media, to be used in energy-saving windows in warm climates' housing or temperature-sensitive infrastructure.

  18. A method for the temperature calibration of an infrared camera using water as a radiative source

    International Nuclear Information System (INIS)

    Bower, S. M.; Kou, J.; Saylor, J. R.

    2009-01-01

    Presented here is an effective low-cost method for the temperature calibration of infrared cameras, for applications in the 0-100 deg. C range. The calibration of image gray level intensity to temperature is achieved by imaging an upwelling flow of water, the temperature of which is measured with a thermistor probe. The upwelling flow is created by a diffuser located below the water surface of a constant temperature water bath. The thermistor probe is kept immediately below the surface, and the distance from the diffuser outlet to the surface is adjusted so that the deformation of the water surface on account of the flow is small, yet the difference between the surface temperature seen by the camera and the bulk temperature measured by the thermistor is also small. The benefit of this method compared to typical calibration procedures is that, without sacrificing the quality of the calibration, relatively expensive commercial blackbodies are replaced by water as the radiative source (ε≅0.98 for the wavelengths considered here). A heat transfer analysis is provided, which improves the accuracy of the calibration method and also provides the user with guidance to further increases in accuracy of the method.

  19. Photon trajectory in strongly scattering media transilluminated by the sine-modulated laser radiation

    Science.gov (United States)

    Lyubimov, Vladimir V.; Kravtsenyuk, Olga V.; Skotnikov, V. A.; Volkonski, Vladimir B.

    1998-12-01

    Results of experimental study of the scattering object shape influence on the photon average trajectories (AT) are presented. The systematic experimental study of the AT inside the scattering bodies of different forms (semi- infinite medium, flat layer, rectangular sector, and cylinder) was carried out. The staking of the AT from a source to detect was carried out with the use of the standard inhomogeneity (SI): a point absolute absorber was embedded inside the object, and the point was searched where the maximal decrease of the detector signal was observed. Also this decreasing was explored as a function of the SI displacement from the AT. As it was predicted in our previous theoretical study, the simple approximation for the AT shape could be done as a three-segment polygonal line that is normal to the body surface at the initial and thermal trajectory points. The approximation error is much less then the width of the area where the presence of the SI is detectable. The obtained results comprise the base for further development of the fast computer algorithms for the real-time multi-aspect 3D optical imaging of strongly scattering objects.

  20. Triple-doped KMnF3:Yb3+/Er3+/Tm3+ nanocubes: four-color upconversion emissions with strong red and near-infrared bands

    Science.gov (United States)

    Wang, Hao; Hong, Xiaodong; Han, Renlu; Shi, Junhui; Liu, Zongjun; Liu, Shujuan; Wang, You; Gan, Yang

    2015-11-01

    Triple-doped (Yb3+/Er3+/Tm3+) KMnF3 nanocubes with uniform sizes of 250 nm were synthesized by a facile hydrothermal route using the oleic acid as the capping agent. It was found that these nanocubes can simultaneously exhibited four-color (blue, green, red and NIR) upconversion emissions under a single 980 nm near-infrared (NIR) laser excitation, which should have potential multicolor in vivo imaging applications. Specifically, the red (660 nm) and NIR (800 nm) peaks, known as two “optical windows” for imaging biological tissues, were strong. The spectral and pump analyses indicated the two-photon processes were responsible for the both red and NIR emissions.

  1. Transdermal penetration of topically applied fluorescent dyes with and without the influence of Water Filtered Infrared-A-Radiation

    OpenAIRE

    Grone, Diego

    2010-01-01

    Optical methods were used to investigate the influence of water filtered infrared A radiation (wIRA) on the dermatopharmacokinetics of topically applied substances. The penetration profiles of the hydrophilic dye fluoresceine and the lipophilic dye curcumin in a standard o/w emulsion were determined by tape stripping, in combination with spectroscopic measurements. Additionally, the penetration was investigated in vivo by laser scanning microscopy. Three different protocols (mode A-C) were us...

  2. Proton dynamics in the strong chelate hydrogen bond of crystalline picolinic acid N-oxide. A new computational approach and infrared, raman and INS study.

    Science.gov (United States)

    Stare, Jernej; Panek, Jarosław; Eckert, Juergen; Grdadolnik, Joze; Mavri, Janez; Hadzi, Dusan

    2008-02-21

    Infrared, Raman and INS spectra of picolinic acid N-oxide (PANO) were recorded and examined for the location of the hydronic modes, particularly O-H stretching and COH bending. PANO is representative of strong chelate hydrogen bonds (H-bonds) with its short O...O distance (2.425 A). H-bonding is possibly well-characterized by diffraction, NMR and NQR data and calculated potential energy functions. The analysis of the spectra is assisted by DFT frequency calculations both in the gas phase and in the solid state. The Car-Parrinello quantum mechanical solid-state method is also used for the proton dynamics simulation; it shows the hydron to be located about 99% of time in the energy minimum near the carboxylic oxygen; jumps to the N-O acceptor are rare. The infrared spectrum excels by an extended absorption (Zundel's continuum) interrupted by numerous Evans transmissions. The model proton potential functions on which the theories of continuum formation are based do not correspond to the experimental and computed characteristics of the hydrogen bond in PANO, therefore a novel approach has been developed; it is based on crystal dynamics driven hydronium potential fluctuation. The envelope of one hundred 0 --> 1 OH stretching transitions generated by molecular dynamics simulation exhibits a maximum at 1400 cm-1 and a minor hump at approximately 1600 cm-1. These positions square well with ones predicted for the COH bending and OH stretching frequencies derived from various one- and two-dimensional model potentials. The coincidences with experimental features have to be considered with caution because the CPMD transition envelope is based solely on the OH stretching coordinate while the observed infrared bands correspond to heavily mixed modes as was previously shown by the normal coordinate analysis of the IR spectrum of argon matrix isolated PANO, the present CPMD frequency calculation and the empirical analysis of spectra. The experimental infrared spectra show some

  3. Drying and heat transfer behavior of banana undergoing combined low-pressure superheated steam and far-infrared radiation drying

    International Nuclear Information System (INIS)

    Nimmol, Chatchai; Devahastin, Sakamon; Swasdisevi, Thanit; Soponronnarit, Somchart

    2007-01-01

    The present study aimed at investigating the use of a drying system combining the concept of already proven low-pressure superheated steam drying and far-infrared radiation (LPSSD-FIR) for banana. The effects of various operating parameters, i.e., drying medium temperature and pressure, on the drying kinetics and heat transfer behavior of banana as well as the energy consumption of the process were investigated and discussed. Comparison was also made with similar sets of data obtained from the system with combined far-infrared radiation and vacuum drying (VACUUM-FIR) and the system using only low-pressure superheated steam drying (LPSSD). The results showed that LPSSD-FIR and VACUUM-FIR took shorter drying time compared to LPSSD at all drying conditions. In terms of the specific energy consumption, it was observed that the specific energy consumption of the vacuum pump was much higher than that of the far-infrared radiator or electric heater. It was also found that the specific energy consumption of LPSSD-FIR and VACUUM-FIR were lower than that of LPSSD at all drying conditions. Based on the drying rates and the specific energy consumption of all tested processes, LPSSD-FIR at 90 deg. C and 7 kPa was suggested

  4. SiC absorption of near-infrared laser radiation at high temperatures

    Science.gov (United States)

    Adelmann, B.; Hellmann, R.

    2016-07-01

    We report on a theoretical and experimental investigation of the temperature-dependent optical absorption of nitrogen-doped 4H-SiC for a temperature range between room temperature and the decomposition point. The theoretical model is based on free carrier absorption including the temperature dependence of the electron mobility. With respect to laser material processing of silicon carbide, the analysis focusses on a near-infrared wavelength range. At room temperature, the calculated absorption is in excellent agreement to transmission and reflection measurements. For the experimental study of the absorption at higher temperatures induced by intense 1070-nm laser irradiation, a two-color pyrometer is employed with the thermal emission of the laser interaction zone being collected coaxial to the impinging laser. Exemplarily, the simulated temperature-dependent absorption is used to determine the heating of a 0.4-mm-thick 4H-SiC specimen during laser irradiation and compared to the experimentally determined temperature. In an initial time domain of the irradiation with an attained temperature below 1350 K, the simulated and measured temperatures are in good agreement. Above 1350 K, however, the measured temperature reveals a sharp and fast increase up to 2100 K which is not predicted by the model. This discrepancy is attributed to a strong additional absorption mechanism caused by carbonization at the surface which is confirmed by EDX analysis.

  5. NOAA Climate Data Record (CDR) of Intersatellite Calibrated Clear-Sky High Resolution Infrared Radiation Sounder (HIRS) Channel 12 Brightness Temperature Version 3

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The High-Resolution Infrared Radiation Sounder (HIRS) of intersatellite calibrated channel 12 brightness temperature (TB) product is a gridded global monthly time...

  6. Three-dimensional tomographic imaging for dynamic radiation behavior study using infrared imaging video bolometers in large helical device plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Ryuichi; Iwama, Naofumi [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Peterson, Byron J.; Kobayashi, Masahiro; Mukai, Kiyofumi [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); SOKENDAI (The Graduate University for Advanced Studies), Hayama, Kanagawa 240-0193 (Japan); Teranishi, Masaru [Hiroshima Institute of Technology, 2-1-1, Miyake, Saeki-ku, Hiroshima 731-5193 (Japan); Pandya, Shwetang N. [Institute of Plasma Research, Near Indira Bridge, Bhat Village, Gandhinagar, Gujarat 382428 (India)

    2016-05-15

    A three-dimensional (3D) tomography system using four InfraRed imaging Video Bolometers (IRVBs) has been designed with a helical periodicity assumption for the purpose of plasma radiation measurement in the large helical device. For the spatial inversion of large sized arrays, the system has been numerically and experimentally examined using the Tikhonov regularization with the criterion of minimum generalized cross validation, which is the standard solver of inverse problems. The 3D transport code EMC3-EIRENE for impurity behavior and related radiation has been used to produce phantoms for numerical tests, and the relative calibration of the IRVB images has been carried out with a simple function model of the decaying plasma in a radiation collapse. The tomography system can respond to temporal changes in the plasma profile and identify the 3D dynamic behavior of radiation, such as the radiation enhancement that starts from the inboard side of the torus, during the radiation collapse. The reconstruction results are also consistent with the output signals of a resistive bolometer. These results indicate that the designed 3D tomography system is available for the 3D imaging of radiation. The first 3D direct tomographic measurement of a magnetically confined plasma has been achieved.

  7. Nimbus-3 Medium-Resolution Infrared Radiometer (MRIR) Level 1 Meteorological Radiation Data V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nimbus-3 Medium-Resolution Infrared Radiometer (MRIR) Level 1 Meteorological Radiance Data contain radiances expressed as equivalent blackbody temperatures along...

  8. About angular dependence of intensity of absent-minded radiation in approach of the strong dissipation of colliding ionic-sound waves

    International Nuclear Information System (INIS)

    Solikhov, D.K.

    2015-01-01

    Present article is devoted to angular dependence of intensity of absent-minded radiation in approach of the strong dissipation of colliding ionic-sound waves. The operation angular dependence of dimensionless of intensity of absent-minded radiation in two-dimensional field of localisation of a wave of a rating in approach of the strong dissipation of passers is ionic-sound waves is viewed. (author)

  9. Development of a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI)

    International Nuclear Information System (INIS)

    Huang Bormin; Mielikainen, Jarno; Oh, Hyunjong; Allen Huang, Hung-Lung

    2011-01-01

    Satellite-observed radiance is a nonlinear functional of surface properties and atmospheric temperature and absorbing gas profiles as described by the radiative transfer equation (RTE). In the era of hyperspectral sounders with thousands of high-resolution channels, the computation of the radiative transfer model becomes more time-consuming. The radiative transfer model performance in operational numerical weather prediction systems still limits the number of channels we can use in hyperspectral sounders to only a few hundreds. To take the full advantage of such high-resolution infrared observations, a computationally efficient radiative transfer model is needed to facilitate satellite data assimilation. In recent years the programmable commodity graphics processing unit (GPU) has evolved into a highly parallel, multi-threaded, many-core processor with tremendous computational speed and very high memory bandwidth. The radiative transfer model is very suitable for the GPU implementation to take advantage of the hardware's efficiency and parallelism where radiances of many channels can be calculated in parallel in GPUs. In this paper, we develop a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI) launched in 2006 onboard the first European meteorological polar-orbiting satellites, METOP-A. Each IASI spectrum has 8461 spectral channels. The IASI radiative transfer model consists of three modules. The first module for computing the regression predictors takes less than 0.004% of CPU time, while the second module for transmittance computation and the third module for radiance computation take approximately 92.5% and 7.5%, respectively. Our GPU-based IASI radiative transfer model is developed to run on a low-cost personal supercomputer with four GPUs with total 960 compute cores, delivering near 4 TFlops theoretical peak performance. By massively parallelizing the second and third modules, we reached 364x

  10. Submillimeter and far infrared line observations of M17 SW: A clumpy molecular cloud penetrated by UV radiation

    Science.gov (United States)

    Stutzki, J.; Stacey, G. J.; Genzel, R.; Harris, A. I.; Jaffe, d. T.; Lugten, J. B.

    1987-01-01

    Millimeter, submillimeter, and far infrared spectroscopic observations of the M17 SW star formation region are discussed. The results require the molecular cloud near the interface to be clumpy or filamentary. As a consequence, far ultraviolet radiation from the central OB stellar cluster can penetrate into the dense molecular cloud to a depth of several pc, thus creating bright and extended (CII) emission from the photodissociated surfaces of dense atomic and molecular clumps or sheets. The extended (CII) emission throughout the molecular cloud SW of the M17 complex has a level 20 times higher than expected from a single molecular cloud interface exposed to an ultraviolet radiation field typical of the solar neighborhood. This suggests that the molecular cloud as a whole is penetrated by ultraviolet radiation and has a clumpy or filamentary structure. The number of B stars expected to be embedded in the M17 molecular cloud probably can provide the UV radiation necessary for the extended (CII) emission. Alternatively, the UV radiation could be external, if the interstellar radiation in the vicinity of M17 is higher than in the solar neighborhood.

  11. Experimental study on the optimization of heat and mass transfer of industrial drying of the TiO2 bulb by infrared radiation

    Science.gov (United States)

    Zhu, Kai; Yang, Junhong; Li, Xun; Li, Chunying; Chu, Zhide; Jiang, Juyuan

    1996-12-01

    The characteristics of radiation and drying properties of TiO2 bulb in the fixed bed with infrared radiation have been studied in this paper, and the experiments on drying dynamics has been analysed also. The optimization of heat and mass transfer data has been determined, which could provide the scientific basis for engineering design.

  12. High-Performance, Radiation-Hard, 2-D, Near-Infrared, Avalanche Photodiode Arrays, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In this STTR project we will address the radiation hardness issues using radiation hard (RH) materials. We will based on the RH material to develop our photon...

  13. Generation and application of ultrashort coherent mid-infrared electromagnetic radiation

    Science.gov (United States)

    Wandel, Scott

    Particle accelerators are useful instruments that help address critical issues for the future development of nuclear energy. Current state-of-the-art accelerators based on conventional radio-frequency (rf) cavities are too large and expensive for widespread commercial use, and alternative designs must be considered for supplying relativistic beams to small-scale applications, including medical imaging, secu- rity screening, and scientific research in a university-scale laboratory. Laser-driven acceleration using micro-fabricated dielectric photonic structures is an attractive approach because such photonic microstructures can support accelerating fields that are 10 to 100 times higher than that of rf cavity-based accelerators. Dielectric laser accelerators (DLAs) use commercial lasers as a driving source, which are smaller and less expensive than the klystrons used to drive current rf-based accelerators. Despite the apparent need for compact and economical laser sources for laser-driven acceleration, the availability of suitable high-peak-power lasers that cover a broad spectral range is currently limited. To address the needs of several innovative acceleration mechanisms like DLA, it is proposed to develop a coherent source of mid-infrared (IR) electromagnetic radiation that can be implemented as a driving source of laser accelerators. The use of ultrashort mid-IR high peak power laser systems in various laser-driven acceleration schemes has shown the potential to greatly reduce the optical pump intensities needed to realize high acceleration gradients. The optical intensity needed to achieve a given ponderomotive potential is 25 times less when using a 5-mum mid-IR laser as compared to using a 1-mum near-IR solid-state laser. In addition, dielectric structure breakdown caused by multiphoton ionization can be avoided by using longer-wavelength driving lasers. Current mid-IR laser sources do not produce sufficiently short pulse durations, broad spectral bandwidths

  14. Electromagnetic radiation energy arrangement. [coatings for solar energy absorption and infrared reflection

    Science.gov (United States)

    Lipkis, R. R.; Vehrencamp, J. E. (Inventor)

    1965-01-01

    A solar energy collector and infrared energy reflector is described which comprises a vacuum deposited layer of aluminum of approximately 200 to 400 Angstroms thick on one side of a substrate. An adherent layer of titanium with a thickness of between 800 and 1000 Angstroms is vacuum deposited on the aluminum substrate and is substantially opaque to solar energy and substantially transparent to infrared energy.

  15. Properties in the middle and far infrared radiation of spiral and irregular galaxies

    International Nuclear Information System (INIS)

    Contursi, Alessandra

    1998-01-01

    In the first part of this research thesis, the author reports the study in the middle infrared of H II regions belonging to Magellanic clouds. For this purpose, he presents different aspects of infrared emission by the interstellar medium: origin and evolution of interstellar grains, dust studied by astrophysical observations, dust models, infrared observations made by COBE and IRAS satellites, exploitation of the ISO satellite. He also presents the Small and Large Magellanic clouds, and reports the study of the H II N4 region of the large one, imagery and spectroscopy of the H II N66 region of the small one, and the study of silicate emission in the central region of N66. The second part reports the study of cluster normal spiral galaxies in the middle and far infrared. For this purpose, the author discusses the colours in the middle infrared of Virgo's and Coma's galaxies, discusses the properties in the infrared of spiral galaxies (Coma and A1367), based on observations made by ISO [fr

  16. The Investigation of Property of Radiation and Absorbed of Infrared Lights of the Biological Tissues

    Science.gov (United States)

    Pang, Xiao-Feng; Deng, Bo; Xiao, He-Lan; Cai, Guo-Ping

    2010-04-01

    The properties of absorption of infrared light for collagen, hemoglobin, bivine serum albumen (BSA) protein molecules with α- helix structure and water in the living systems as well as the infrared transmission spectra for person’s skins and finger hands of human body in the region of 400-4000 cm-1 (i.e., wavelengths of 2-20 μm) have been collected and determined by using a Nicolet Nexus 670 FT-IR Spectrometer, a Perkin Elmer GX FT-IR spectrometer, an OMA (optical multichannel analysis) and an infrared probe systems, respectively. The experimental results obtained show that the protein molecules and water can all absorb the infrared lights in the ranges of 600-1900 cm-1 and 2900-3900 cm-l, but their properties of absorption are somewhat different due to distinctions of their structure and conformation and molecular weight. We know from the transmission spectra of person’s finger hands and skin that the infrared lights with wavelengths of 2 μm-7 μm can not only transmit over the person’s skin and finger hands, but also be absorbed by the above proteins and water in the living systems. Thus, we can conclude from this study that the human beings and animals can absorb the infrared lights with wavelengths of 2 μm-7 μm.

  17. GARLIC — A general purpose atmospheric radiative transfer line-by-line infrared-microwave code: Implementation and evaluation

    International Nuclear Information System (INIS)

    Schreier, Franz; Gimeno García, Sebastián; Hedelt, Pascal; Hess, Michael; Mendrok, Jana; Vasquez, Mayte; Xu, Jian

    2014-01-01

    A suite of programs for high resolution infrared-microwave atmospheric radiative transfer modeling has been developed with emphasis on efficient and reliable numerical algorithms and a modular approach appropriate for simulation and/or retrieval in a variety of applications. The Generic Atmospheric Radiation Line-by-line Infrared Code — GARLIC — is suitable for arbitrary observation geometry, instrumental field-of-view, and line shape. The core of GARLIC's subroutines constitutes the basis of forward models used to implement inversion codes to retrieve atmospheric state parameters from limb and nadir sounding instruments. This paper briefly introduces the physical and mathematical basics of GARLIC and its descendants and continues with an in-depth presentation of various implementation aspects: An optimized Voigt function algorithm combined with a two-grid approach is used to accelerate the line-by-line modeling of molecular cross sections; various quadrature methods are implemented to evaluate the Schwarzschild and Beer integrals; and Jacobians, i.e. derivatives with respect to the unknowns of the atmospheric inverse problem, are implemented by means of automatic differentiation. For an assessment of GARLIC's performance, a comparison of the quadrature methods for solution of the path integral is provided. Verification and validation are demonstrated using intercomparisons with other line-by-line codes and comparisons of synthetic spectra with spectra observed on Earth and from Venus. - Highlights: • High resolution infrared-microwave radiative transfer model. • Discussion of algorithmic and computational aspects. • Jacobians by automatic/algorithmic differentiation. • Performance evaluation by intercomparisons, verification, validation

  18. Developing a framework to model the primary drying step of a continuous freeze-drying process based on infrared radiation

    DEFF Research Database (Denmark)

    Van Bockstal, Pieter-Jan; Corver, Jos; Mortier, Séverine Thérèse F.C.

    2018-01-01

    The continuous freeze-drying concept based on spinning the vials during freezing and on non-contact energy transfer via infrared (IR) radiation during drying, improves process efficiency and product quality (uniformity) compared to conventional batch freeze-drying. Automated control of this process....... These results assist in the selection of proper materials which could serve as IR window in the continuous freeze-drying prototype. The modelling framework presented in this paper fits the model-based design approach used for the development of this prototype and shows the potential benefits of this design...

  19. Strong visible and near infrared photoluminescence from ZnO nanorods/nanowires grown on single layer graphene studied using sub-band gap excitation

    Science.gov (United States)

    Biroju, Ravi K.; Giri, P. K.

    2017-07-01

    Fabrication and optoelectronic applications of graphene based hybrid 2D-1D semiconductor nanostructures have gained tremendous research interest in recent times. Herein, we present a systematic study on the origin and evolution of strong broad band visible and near infrared (NIR) photoluminescence (PL) from vertical ZnO nanorods (NRs) and nanowires (NWs) grown on single layer graphene using both above band gap and sub-band gap optical excitations. High resolution field emission scanning electron microscopy and X-ray diffraction studies are carried out to reveal the morphology and crystalline quality of as-grown and annealed ZnO NRs/NWs on graphene. Room temperature PL studies reveal that besides the UV and visible PL bands, a new near-infrared (NIR) PL emission band appears in the range between 815 nm and 886 nm (1.40-1.52 eV). X-ray photoelectron spectroscopy studies revealed excess oxygen content and unreacted metallic Zn in the as-grown ZnO nanostructures, owing to the low temperature growth by a physical vapor deposition method. Post-growth annealing at 700 °C in the Ar gas ambient results in the enhanced intensity of both visible and NIR PL bands. On the other hand, subsequent high vacuum annealing at 700 °C results in a drastic reduction in the visible PL band and complete suppression of the NIR PL band. PL decay dynamics of green emission in Ar annealed samples show tri-exponential decay on the nanosecond timescale including a very slow decay component (time constant ˜604.5 ns). Based on these results, the NIR PL band comprising two peaks centered at ˜820 nm and ˜860 nm is tentatively assigned to neutral and negatively charged oxygen interstitial (Oi) defects in ZnO, detected experimentally for the first time. The evidence for oxygen induced trap states on the ZnO NW surface is further substantiated by the slow photocurrent response of graphene-ZnO NRs/NWs. These results are important for tunable light emission, photodetection, and other cutting edge

  20. Ultraviolet and infrared spectral analysis of irradiated polypropylene films: correlation and possible application for high dose radiation dosimetry

    International Nuclear Information System (INIS)

    Abdel-Fattah, A.A.; Said, F.I.A.; El-Kelany, M.; El Miligi, A.A.

    1998-01-01

    A detailed study was performed to develop the dosimetric characteristics of commercial polypropylene film (PP), to be used as a film dosimeter for high-dose gamma radiation dosimetry. The useful dose range of this polymeric film extends up to 630 kGy. Correlations were established between the absorbed dose of gamma radiation and the radiation-induced changes in PP measured by means of Fourier transform infrared (FTIR) and ultraviolet (UV) spectrophotometry. The results showed a significant dependence of the response on the selected readout tool of measurements - FTIR (at 1716 and 3400 cm -1 ) or UV (at 275 nm), as well as on the quantity used for calculation. The radiation-chemical yields of the ketonic carbonyl group and the hydroxyl group produced in irradiated PP film were evaluated. G(>C=O) was found to be 1.37 μmol/J and G(>C-OH) was found to be 0.638 μmol/J. The assessment of random uncertainty associated with the measurement of dose response and the effect of relative humidity during irradiation on dosimeter performance as well as post-irradiation stability at different storage conditions will be discussed. (author)

  1. GARLIC - A general purpose atmospheric radiative transfer line-by-line infrared-microwave code: Implementation and evaluation

    Science.gov (United States)

    Schreier, Franz; Gimeno García, Sebastián; Hedelt, Pascal; Hess, Michael; Mendrok, Jana; Vasquez, Mayte; Xu, Jian

    2014-04-01

    A suite of programs for high resolution infrared-microwave atmospheric radiative transfer modeling has been developed with emphasis on efficient and reliable numerical algorithms and a modular approach appropriate for simulation and/or retrieval in a variety of applications. The Generic Atmospheric Radiation Line-by-line Infrared Code - GARLIC - is suitable for arbitrary observation geometry, instrumental field-of-view, and line shape. The core of GARLIC's subroutines constitutes the basis of forward models used to implement inversion codes to retrieve atmospheric state parameters from limb and nadir sounding instruments. This paper briefly introduces the physical and mathematical basics of GARLIC and its descendants and continues with an in-depth presentation of various implementation aspects: An optimized Voigt function algorithm combined with a two-grid approach is used to accelerate the line-by-line modeling of molecular cross sections; various quadrature methods are implemented to evaluate the Schwarzschild and Beer integrals; and Jacobians, i.e. derivatives with respect to the unknowns of the atmospheric inverse problem, are implemented by means of automatic differentiation. For an assessment of GARLIC's performance, a comparison of the quadrature methods for solution of the path integral is provided. Verification and validation are demonstrated using intercomparisons with other line-by-line codes and comparisons of synthetic spectra with spectra observed on Earth and from Venus.

  2. A dissociative quantum mechanical/molecular mechanical molecular dynamics simulation and infrared experiments reveal characteristics of the strongly hydrolytic arsenic(III).

    Science.gov (United States)

    Canaval, Lorenz R; Lutz, Oliver M D; Weiss, Alexander K H; Huck, Christian W; Hofer, Thomas S

    2014-11-17

    This work presents a hybrid ab initio quantum mechanical/molecular mechanical simulation at the RI-MP2 level of theory investigating the hydrolysis process of arsenic(III), ultimately leading to arsenous acid (H3AsO3). A newly implemented dissociative water model has been applied to treat the interactions in the classical region, which is capable of describing non-neutral water species such as hydroxide and oxonium ions. Three stages of hydrolysis have been observed during the simulation and besides profound dynamical considerations, detailed insights into structural changes and atomic partial charge shifts are presented. In particular, the geometrical properties of H-bonds involved in each of the three proton transfer events and subsequent proton hopping reactions are discussed. A Laguerre tessellation analysis has been employed to estimate the molecular volume of H3AsO3. Estimations of pKa values of the arsenic(III)-aquo-complexes have been obtained at the G4 and CBS-Q//B3 levels of theory using a thermodynamic cycle, whereas rate constants for the final hydrolysis step have been determined via reaction path optimization and transition state theory. Newly recorded Fourier transform infrared (FT-IR) spectroscopy measurements have been compared to power spectra obtained from the simulation data, confirming its quality. The simulation findings, as well as results from computational spectroscopic calculations utilizing the PT2-VSCF methodology, proved valuable for the interpretation of the experimental FT-IR data, elucidating the particularities of the strongly observed IR Raman noncoincidence effect.

  3. Photoprotection, photosynthesis and growth of tropical tree seedlings under near-ambient and strongly reduced solar ultraviolet-B radiation.

    Science.gov (United States)

    Krause, G Heinrich; Jahns, Peter; Virgo, Aurelio; García, Milton; Aranda, Jorge; Wellmann, Eckard; Winter, Klaus

    2007-10-01

    Seedlings of two late-successional tropical rainforest tree species, Tetragastris panamensis (Engler) O. Kuntze and Calophyllum longifolium (Willd.), were field grown for 3-4 months at an open site near Panama City (9 degrees N), Panama, under plastic films that either transmitted or excluded most solar UV-B radiation. Experiments were designed to test whether leaves developing under bright sunlight with strongly reduced UV-B are capable of acclimating to near-ambient UV-B conditions. Leaves of T. panamensis that developed under near-ambient UV-B contained higher amounts of UV-absorbing substances than leaves of seedlings grown under reduced UV-B. Photosynthetic pigment composition, content of alpha-tocopherol, CO(2) assimilation, potential photosystem II (PSII) efficiency (evaluated by F(v)/F(m) ratios) and growth of T. panamensis and C. longifolium did not differ between seedlings developed under near-ambient and reduced solar UV-B. When seedlings were transferred from the reduced UV-B treatment to the near-ambient UV-B treatment, a pronounced inhibition of photosynthetic capacity was observed initially in both species. UV-B-mediated inhibition of photosynthetic capacity nearly fully recovered within 1 week of the transfer in C. longifolium, whereas in T. panamensis an about 35% reduced capacity of CO(2) uptake was maintained. A marked increase in UV-absorbing substances was observed in foliage of transferred T. panamensis seedlings. Both species exhibited enhanced mid-day photoinhibition of PSII immediately after being transferred from the reduced UV-B to the near-ambient UV-B treatment. This effect was fully reversible within 1d in T. panamensis and within a few days in C. longifolium. The data show that leaves of these tropical tree seedlings, when developing in full-spectrum sunlight, are effectively protected against high solar UV-B radiation. In contrast, leaves developing under conditions of low UV-B lacked sufficient UV protection. They experienced a

  4. CsSnI3: Semiconductor or metal? High electrical conductivity and strong near-infrared photoluminescence from a single material. High hole mobility and phase-transitions.

    Science.gov (United States)

    Chung, In; Song, Jung-Hwan; Im, Jino; Androulakis, John; Malliakas, Christos D; Li, Hao; Freeman, Arthur J; Kenney, John T; Kanatzidis, Mercouri G

    2012-05-23

    CsSnI(3) is an unusual perovskite that undergoes complex displacive and reconstructive phase transitions and exhibits near-infrared emission at room temperature. Experimental and theoretical studies of CsSnI(3) have been limited by the lack of detailed crystal structure characterization and chemical instability. Here we describe the synthesis of pure polymorphic crystals, the preparation of large crack-/bubble-free ingots, the refined single-crystal structures, and temperature-dependent charge transport and optical properties of CsSnI(3), coupled with ab initio first-principles density functional theory (DFT) calculations. In situ temperature-dependent single-crystal and synchrotron powder X-ray diffraction studies reveal the origin of polymorphous phase transitions of CsSnI(3). The black orthorhombic form of CsSnI(3) demonstrates one of the largest volumetric thermal expansion coefficients for inorganic solids. Electrical conductivity, Hall effect, and thermopower measurements on it show p-type metallic behavior with low carrier density, despite the optical band gap of 1.3 eV. Hall effect measurements of the black orthorhombic perovskite phase of CsSnI(3) indicate that it is a p-type direct band gap semiconductor with carrier concentration at room temperature of ∼ 10(17) cm(-3) and a hole mobility of ∼585 cm(2) V(-1) s(-1). The hole mobility is one of the highest observed among p-type semiconductors with comparable band gaps. Its powders exhibit a strong room-temperature near-IR emission spectrum at 950 nm. Remarkably, the values of the electrical conductivity and photoluminescence intensity increase with heat treatment. The DFT calculations show that the screened-exchange local density approximation-derived band gap agrees well with the experimentally measured band gap. Calculations of the formation energy of defects strongly suggest that the electrical and light emission properties possibly result from Sn defects in the crystal structure, which arise

  5. Spatial temperature distribution in human hairy and glabrous skin after infrared CO2 laser radiation.

    Science.gov (United States)

    Frahm, Ken S; Andersen, Ole K; Arendt-Nielsen, Lars; Mørch, Carsten D

    2010-11-08

    CO2 lasers have been used for several decades as an experimental non-touching pain stimulator. The laser energy is absorbed by the water content in the most superficial layers of the skin. The deeper located nociceptors are activated by passive conduction of heat from superficial to deeper skin layers. In the current study, a 2D axial finite element model was developed and validated to describe the spatial temperature distribution in the skin after infrared CO2 laser stimulation. The geometry of the model was based on high resolution ultrasound scans. The simulations were compared to the subjective pain intensity ratings from 16 subjects and to the surface skin temperature distributions measured by an infrared camera. The stimulations were sensed significantly slower and less intense in glabrous skin than they were in hairy skin (MANOVA, p 0.90, p CO2 laser stimulation intensity, temperature levels and nociceptor activation.

  6. Coherent infrared radiation from the ALS generated via femtosecond laser modulation of the electron beam

    International Nuclear Information System (INIS)

    Byrd, J.M.; Hao, Z.; Martin, M.C.; Robin, D.S.; Sannibale, F.; Schoenlein, R.W.; Venturini, M.; Zholents, A.A.; Zolotorev, M.S.

    2004-01-01

    Interaction of an electron beam with a femtosecond laser pulse co-propagating through a wiggler at the ALS produces large modulation of the electron energies within a short ∼100 fs slice of the electron bunch. Propagating around the storage ring, this bunch develops a longitudinal density perturbation due to the dispersion of electron trajectories. The length of the perturbation evolves with a distance from the wiggler but is much shorter than the electron bunch length. This perturbation causes the electron bunch to emit short pulses of temporally and spatially coherent infrared light which are automatically synchronized to the modulating laser. The intensity and spectra of the infrared light were measured in two storage ring locations for a nominal ALS lattice and for an experimental lattice with the higher momentum compaction factor. The onset of instability stimulated by laser e-beam interaction had been discovered. The infrared signal is now routinely used as a sensitive monitor for a fine tuning of the laser beam alignment during data accumulation in the experiments with femtosecond x-ray pulses

  7. Infrared radiative transfer modelling in a 3D scattering cloudy atmosphere: Application to limb sounding measurements of cirrus

    International Nuclear Information System (INIS)

    Ewen, G.B.L.; Grainger, R.G.; Lambert, A.; Baran, A.J.

    2005-01-01

    The Monte Carlo cloud scattering forward model (McClouds F M) has been developed to simulate limb radiative transfer in the presence of cirrus clouds, for the purposes of simulating cloud contaminated measurements made by an infrared limb sounding instrument, e.g. the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). A reverse method three-dimensional Monte Carlo transfer model is combined with a line-by-line model for radiative transfer through the non-cloudy atmosphere to explicitly account for the effects of multiple scattering by the clouds. The ice cloud microphysics are characterised by a size distribution of randomly oriented ice crystals, with the single scattering properties of the distribution determined by accurate calculations accounting for non-spherical habit. A comparison of McClouds F M simulations and real MIPAS spectra of cirrus shows good agreement. Of particular interest are several noticeable spectral features (i.e. H 2 O absorption lines) in the data that are replicated in the simulations: these can only be explained by upwelling tropospheric radiation scattered into the line-of-sight by the cloud ice particles

  8. Ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance and their application on energy-saving kettle

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jianyi [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China); Fan, Xi’an, E-mail: groupfxa@163.com [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China); Lu, Lei [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China); Hu, Xiaoming [Suzhou Sagreon New Materials Co., Ltd, Zhangjiagang 215625 (China); Li, Guangqiang [The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 (China); Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, 947 Heping Road, Qingshan District, Wuhan 430081 (China)

    2015-07-30

    Highlights: • The ferrites based infrared radiation coating was prepared by HVOF for the first time. • The infrared radiation coatings were applied firstly on the household kettle. • The bonding strength between the coating and substrate could reach 30.7 MPa. • The coating kept intact when cycle reached 27 by quenching from 1000 °C using water. • The energy-saving efficiency of the kettle with coating could reach 30.5%. - Abstract: Starting from Fe{sub 2}O{sub 3}, MnO{sub 2}, Co{sub 2}O{sub 3} and NiO powders, the ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance were successfully prepared on the surface of carbon steel by high velocity oxy-fuel spraying (HVOF). The coating thickness was about 120–150 μm and presented a typical flat lamellar structure. The coating surface was rough and some submicron grade grains distributed on it. The infrared emissivity of the ferrites based coating by HVOF was over 0.74 in 3–20 μm waveband at 800 °C, which was obviously higher than that of the coating by brushing process in the short waveband. The bonding strength was 30.7 MPa between the coating and substrate, which was five times more than that of conventional coatings by brushing process. The combined effect of the superior bonding strength, typical lamellar structure, pre-existing microcracks and newly generated pores made the cycle times reach 27 when the coating samples were quenched from 1000 °C using water. Lastly, the infrared radiation coatings were applied on the underside of household kettle, and the energy-saving efficiency could reach 30.5%. The ferrites based infrared radiation coatings obtained in this work are good candidates for saving energy in the field of cookware and industrial high temperature furnace.

  9. Ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance and their application on energy-saving kettle

    International Nuclear Information System (INIS)

    Zhang, Jianyi; Fan, Xi’an; Lu, Lei; Hu, Xiaoming; Li, Guangqiang

    2015-01-01

    Highlights: • The ferrites based infrared radiation coating was prepared by HVOF for the first time. • The infrared radiation coatings were applied firstly on the household kettle. • The bonding strength between the coating and substrate could reach 30.7 MPa. • The coating kept intact when cycle reached 27 by quenching from 1000 °C using water. • The energy-saving efficiency of the kettle with coating could reach 30.5%. - Abstract: Starting from Fe 2 O 3 , MnO 2 , Co 2 O 3 and NiO powders, the ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance were successfully prepared on the surface of carbon steel by high velocity oxy-fuel spraying (HVOF). The coating thickness was about 120–150 μm and presented a typical flat lamellar structure. The coating surface was rough and some submicron grade grains distributed on it. The infrared emissivity of the ferrites based coating by HVOF was over 0.74 in 3–20 μm waveband at 800 °C, which was obviously higher than that of the coating by brushing process in the short waveband. The bonding strength was 30.7 MPa between the coating and substrate, which was five times more than that of conventional coatings by brushing process. The combined effect of the superior bonding strength, typical lamellar structure, pre-existing microcracks and newly generated pores made the cycle times reach 27 when the coating samples were quenched from 1000 °C using water. Lastly, the infrared radiation coatings were applied on the underside of household kettle, and the energy-saving efficiency could reach 30.5%. The ferrites based infrared radiation coatings obtained in this work are good candidates for saving energy in the field of cookware and industrial high temperature furnace

  10. Fast Assembly of Gold Nanoparticles in Large-Area 2D Nanogrids Using a One-Step, Near-Infrared Radiation-Assisted Evaporation Process.

    Science.gov (United States)

    Utgenannt, André; Maspero, Ross; Fortini, Andrea; Turner, Rebecca; Florescu, Marian; Jeynes, Christopher; Kanaras, Antonios G; Muskens, Otto L; Sear, Richard P; Keddie, Joseph L

    2016-02-23

    When fabricating photonic crystals from suspensions in volatile liquids using the horizontal deposition method, the conventional approach is to evaporate slowly to increase the time for particles to settle in an ordered, periodic close-packed structure. Here, we show that the greatest ordering of 10 nm aqueous gold nanoparticles (AuNPs) in a template of larger spherical polymer particles (mean diameter of 338 nm) is achieved with very fast water evaporation rates obtained with near-infrared radiative heating. Fabrication of arrays over areas of a few cm(2) takes only 7 min. The assembly process requires that the evaporation rate is fast relative to the particles' Brownian diffusion. Then a two-dimensional colloidal crystal forms at the falling surface, which acts as a sieve through which the AuNPs pass, according to our Langevin dynamics computer simulations. With sufficiently fast evaporation rates, we create a hybrid structure consisting of a two-dimensional AuNP nanoarray (or "nanogrid") on top of a three-dimensional polymer opal. The process is simple, fast, and one-step. The interplay between the optical response of the plasmonic Au nanoarray and the microstructuring of the photonic opal results in unusual optical spectra with two extinction peaks, which are analyzed via finite-difference time-domain method simulations. Comparison between experimental and modeling results reveals a strong interplay of plasmonic modes and collective photonic effects, including the formation of a high-order stopband and slow-light-enhanced plasmonic absorption. The structures, and hence their optical signatures, are tuned by adjusting the evaporation rate via the infrared power density.

  11. INTERACTION OF LASER RADIATION WITH MATTER: Investigation of the interaction of laser radiation with composite materials by infrared spectroscopy methods

    Science.gov (United States)

    Eremin, V. I.; Kovalenko, I. P.; Levashenko, G. I.; Mazaev, N. V.; Sokol'nikov, A. S.; Shuralev, S. L.

    1990-10-01

    A description is given of the method and apparatus for determination of the effective temperature and composition of a jet of products of the interaction of laser radiation with a glass-fiber-reinforced plastic and an organic plastic. Measurements are also possible of the temperature and emissivity of a target when it is exposed in atmospheric air to cw CO2 laser radiation with a flux density of 3 × 102 — 103 W/cm2. The products of damage to the glass-fiber-reinforced plastic consisted of particles of metal oxides with a diameter d32 = 2.3-3.5 μm and a volume concentration Cv = (0.06-0.25) × 10 - 4, and of molecular gases CO2, H2O, and HCl; the damage products of the organic plastic were conglomerates of soot particles with the diameter d32 = 1-1.8 μm and a volume concentration Cv = (0.4-0.9) × 10 - 4, and the same molecular gases. The target emissivity increased with time and reached 0.8-0.9.

  12. Mechanistic insights into nanotoxicity determined by synchrotron radiation-based Fourier-transform infrared imaging and multivariate analysis.

    Science.gov (United States)

    Riding, Matthew J; Trevisan, Júlio; Hirschmugl, Carol J; Jones, Kevin C; Semple, Kirk T; Martin, Francis L

    2012-12-01

    Our ability to identify the mechanisms by which carbon-based nanomaterials (CBNs) exert toxicity in cells is constrained by the lack of standardized methodologies to assay endpoint effects. Herein we describe a method of mechanistically identifying the effects of various CBN types in both prokaryotic and eukaryotic cells using multi-beam synchrotron radiation-based Fourier-transform infrared imaging (SR-FTIRI) at diffraction-limited resolution. This technique overcomes many of the inherent difficulties of assaying nanotoxicity and demonstrates exceptional sensitivity in identifying the effects of CBNs in cells at environmentally-relevant concentrations. We identify key mechanisms of nanotoxicity as the alteration of Amide and lipid biomolecules, but propose more specific bioactivity of CBNs occurs as a result of specific interactions between CBN structural conformation and cellular characteristics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Effects of UV radiation on the lipids and proteins of bacteria studied by mid-infrared spectroscopy.

    Science.gov (United States)

    Santos, Ana L; Moreirinha, Catarina; Lopes, Diana; Esteves, Ana Cristina; Henriques, Isabel; Almeida, Adelaide; Domingues, M Rosário M; Delgadillo, Ivonne; Correia, António; Cunha, Angela

    2013-06-18

    Knowledge of the molecular effects of UV radiation (UVR) on bacteria can contribute to a better understanding of the environmental consequences of enhanced UV levels associated with global climate changes and will help to optimize UV-based disinfection strategies. In the present work, the effects of exposure to UVR in different spectral regions (UVC, 100-280 nm; UVB, 280-320 nm; and UVA, 320-400 nm) on the lipids and proteins of two bacterial strains ( Acinetobacter sp. strain PT5I1.2G and Pseudomonas sp. strain NT5I1.2B) with distinct UV sensitivities were studied by mid-infrared spectroscopy. Exposure to UVR caused an increase in methyl groups associated with lipids, lipid oxidation, and also led to alterations in lipid composition, which were confirmed by gas chromatography. Additionally, mid-infrared spectroscopy revealed the effects of UVR on protein conformation and protein composition, which were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), oxidative damage to amino acids, and changes in the propionylation, glycosylation and/or phosphorylation status of cell proteins. Differences in the targets of UVR in the two strains tested were identified and may explain their discrepant UV sensitivities. The significance of the results is discussed from an ecological standpoint and with respect to potential improvements in UV-based disinfection technologies.

  14. An extraordinary directive radiation based on optical antimatter at near infrared.

    Science.gov (United States)

    Mocella, Vito; Dardano, Principia; Rendina, Ivo; Cabrini, Stefano

    2010-11-22

    In this paper we discuss and experimentally demonstrate that in a quasi- zero-average-refractive-index (QZAI) metamaterial, in correspondence of a divergent source in near infrared (λ = 1.55 μm) the light scattered out is extremely directive (Δθ(out) = 0.06°), coupling with diffraction order of the alternating complementary media grating. With a high degree of accuracy the measurements prove also the excellent vertical confinement of the beam even in the air region of the metamaterial, in absence of any simple vertical confinement mechanism. This extremely sensitive device works on a large contact area and open news perspective to integrated spectroscopy.

  15. Effects of intermittent CO2 convection under far-infrared radiation on vacuum drying of pre-osmodehydrated watermelon.

    Science.gov (United States)

    Chakraborty, Rajat; Mondal, Pijus

    2017-08-01

    Watermelon, a tropical seasonal fruit with high nutrient content, requires preservation through drying due to its perishable nature. Nevertheless, drying of watermelon through conventional processes has a negative impact either on the drying time or on the final product quality. In this work, osmotic dehydration of watermelon followed by far-infrared radiation-assisted vacuum drying (FIRRAVD) was optimized to develop dehydrated watermelon with minimum moisture content. Significantly, during FIRRAVD, an attempt was made to further intensify the drying rate by forced convection through intermittent CO 2 injection. Drying kinetics of each operation and physicochemical qualities of dried products were evaluated. FIRRAVD was a viable method of watermelon drying with appreciably high moisture diffusivity (D eff,m ) of 4.97 × 10 -10 to 1.49 × 10 -9 m 2 s -1 compared to conventional tray drying. Moreover, intermittent CO 2 convection during FIRRAVD (ICFIRRAVD) resulted in appreciable intensification of drying rate, with enhanced D eff,m (9.93 × 10 -10 to 1.99 × 10 -9 m 2 s -1 ). Significantly, ICFIRRAVD required less energy and approximately 16% less time compared to FIRRAVD. The quality of the final dehydrated watermelon was superior compared to conventional drying protocols. The novel CO 2 convective drying of watermelon in the presence of far-infrared radiation demonstrated an energy-efficient and time-saving operation rendering a dehydrated watermelon with acceptable quality parameters. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. Tracking of Thermal Infrared Anomaly before One Strong Earthquake-In the Case of Ms6.2 Earthquake in Zadoi, Qinghai on October 17th, 2016

    Science.gov (United States)

    Zhang, Xuan; Zhang, Yuansheng; Tian, Xiufeng; Zhang, Qiaoli; Tian, Jie

    2017-10-01

    The detection and tracking process of thermal infrared anomaly before Ms6.2 earthquake in Zadio, Qinghai on October 17th, 2016, are reviewed and analyzed; then the different characteristics of thermal infrared brightness temperature data before this earthquake is described in details. According to these characteristics, the tracking process of thermal anomaly is divided into four stages, respectively identification stage, pre-judgment stage, tracking and approaching stage and verification stage. The anomaly forms and turning signals focused in each stage can provide clear indication information for earthquake pre-judgment; finally, the prediction efficiency and technical issues of this method are illustrated and discussed.

  17. 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

  18. Structure, electrochemistry and spectroscopy of a new diacylhydrazido-bridged diruthenium complex with a strongly near-infrared absorbing RuIIIRuII intermediate

    Czech Academy of Sciences Publication Activity Database

    Jana, R.; Sarkar, B.; Bubrin, D.; Fiedler, Jan; Kaim, W.

    2010-01-01

    Roč. 13, č. 10 (2010), s. 1160-1162 ISSN 1387-7003 R&D Projects: GA MŠk OC 140; GA MŠk OC09043 Institutional research plan: CEZ:AV0Z40400503 Keywords : crystal structure * hydrazido ligand * near-infrared ruthenium Subject RIV: CG - Electrochemistry Impact factor: 1.974, year: 2010

  19. The dependence of rate coefficients and product yields upon fluence, intensity, and time in unimolecular reactions induced by monochromatic infrared radiation

    Science.gov (United States)

    Quack, M.; Humbert, P.; van den Bergh, H.

    1980-07-01

    The influence of the three parameters (with two degrees of freedom) fluence, intensity, and time on rate coefficients and product yields in collisionless Unimolecular Reactions Induced by Monochromatic Infrared Radiation (URIMIR) is discussed in some detail in terms of the recently proposed logarithmic reactant fluence plots. Model calculations for several archetypes of such plots are presented, based on solutions of the Pauli master equation and solutions of the quantum mechanical equations of motion for spectra involving many states at each level of excitation. Linear diagrams, turnups, and turnovers are found and are discussed systematically. Experimental examples re-evaluated from the literature and new measurements on the laser induced decomposition of CF2HCl are reported which nicely illustrate the various theoretical possibilities. Steady state rate coefficients for six molecules are evaluated and summarized. In some situations the intrinsic nonlinear intensity dependence of the steady state rate coefficients and deviations from simple fluence dependence of the product yields both before and at steady state are shown to be important theoretically and experimentally. The role of the reducibility of the rate coefficient matrix is discussed in connection with turnovers and with the strong influence of initial temperature that is found in the laser induced decomposition of CF2HCl.

  20. Characterization of ionizing radiation effects on bone using Fourier Transform Infrared Spectroscopy and multivariate analysis of spectra

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Pedro Arthur Augusto de; Dias, Derly Augusto; Zezell, Denise Maria, E-mail: zezell@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    Ionizing radiation has been used as an important treatment and diagnostic method for several diseases. Optical techniques provides an efficient clinical diagnostic to support an accurate evaluation of the interaction of radiation with molecules. Fourier-transform infrared spectroscopy coupled with attenuated total reflectance (ATR-FTIR) is a label-free and nondestructive optical technique that can recognize functional groups in biological samples. In this work, 30 fragments of bone were collected from bovine femur diaphysis. Samples were cut and polished until 1 cm x 1 cm x 1 mm, which were then stored properly in the refrigerated environment. Samples irradiation was performed with a Cobalt-60 Gammacell Irradiator source at doses of 0.1 kGy, 1 kGy, whereas the fragments exposed to dose of 15 kGy was irradiated in a multipurpose irradiator of Cobalt-60. Spectral data was submitted to principal component analysis followed by linear discriminant analysis. Multivariate analysis was performed with Principal component analysis(PCA) followed by Linear Discriminant Analysis(LDA) using MATLAB R2015a software (The Mathworks Inc., Natick, MA, USA). We demonstrated the feasibility of using ATR-FTIR spectroscopy associated with PCA-LDA multivariate technique to evaluate the molecular changes in bone matrix caused by different doses: 0.1 kGy, 1 kGy and 15 kGy. These alterations between the groups are mainly reported in phosphate region. Our results open up new possibilities for protein monitoring relating to dose responses. (author)

  1. Characterization of ionizing radiation effects on bone using Fourier Transform Infrared Spectroscopy and multivariate analysis of spectra

    International Nuclear Information System (INIS)

    Castro, Pedro Arthur Augusto de; Dias, Derly Augusto; Zezell, Denise Maria

    2017-01-01

    Ionizing radiation has been used as an important treatment and diagnostic method for several diseases. Optical techniques provides an efficient clinical diagnostic to support an accurate evaluation of the interaction of radiation with molecules. Fourier-transform infrared spectroscopy coupled with attenuated total reflectance (ATR-FTIR) is a label-free and nondestructive optical technique that can recognize functional groups in biological samples. In this work, 30 fragments of bone were collected from bovine femur diaphysis. Samples were cut and polished until 1 cm x 1 cm x 1 mm, which were then stored properly in the refrigerated environment. Samples irradiation was performed with a Cobalt-60 Gammacell Irradiator source at doses of 0.1 kGy, 1 kGy, whereas the fragments exposed to dose of 15 kGy was irradiated in a multipurpose irradiator of Cobalt-60. Spectral data was submitted to principal component analysis followed by linear discriminant analysis. Multivariate analysis was performed with Principal component analysis(PCA) followed by Linear Discriminant Analysis(LDA) using MATLAB R2015a software (The Mathworks Inc., Natick, MA, USA). We demonstrated the feasibility of using ATR-FTIR spectroscopy associated with PCA-LDA multivariate technique to evaluate the molecular changes in bone matrix caused by different doses: 0.1 kGy, 1 kGy and 15 kGy. These alterations between the groups are mainly reported in phosphate region. Our results open up new possibilities for protein monitoring relating to dose responses. (author)

  2. Near-infrared radiation absorption properties of covellite (CuS using first-principles calculations

    Directory of Open Access Journals (Sweden)

    Lihua Xiao

    2016-08-01

    Full Text Available First-principles density functional theory was used to investigate the electronic structure, optical properties and the origin of the near-infrared (NIR absorption of covellite (CuS. The calculated lattice constant and optical properties are found to be in reasonable agreement with experimental and theoretical findings. The electronic structure reveals that the valence and conduction bands of covellite are determined by the Cu 3d and S 3p states. By analyzing its optical properties, we can fully understand the potential of covellite (CuS as a NIR absorbing material. Our results show that covellite (CuS exhibits NIR absorption due to its metal-like plasma oscillation in the NIR range.

  3. SHARC, a comprehensive non-equilibrium infrared radiation model for the upper atmosphere. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Sundberg, R.L.; Duff, J.W.; Bernstein, L.S.; Gruninger, J.H.; Matthew, M.W.

    1993-06-21

    A new, first-principles computer model, SHARC, has been developed by the Air Force for the rapid and accurate calculation of non-LTE upper atmospheric infrared radiance and transmittance spectra with a resolution of better than 1/cm. Comprehensive coverage of the 2 micrometers to 40 micrometers (250/cm to 5,000/cm) wavelength region is provided for arbitrary lines of sight in the 50 - 300 km altitude range, accounting for the detailed production, loss, and energy transfer processes among the molecular vibrational states. Auroral production and excitation of CO2, NO, and NO+ are included in addition to quiescent atmospheric processes. Calculated vibrational temperatures are found to be similar to results from other non-LTE codes, and SHARC`s equivalent-width spectral algorithm provides very good agreement with much more time-consuming exact line-by-line methods.

  4. [The efficacy of polychromatic visible and infrared radiation used for the postoperative immunological rehabilitation of patients with breast cancer].

    Science.gov (United States)

    zhevago, N A; Samoĭlova, K A; Davydova, N I; Bychkova, N V; Glazanova, T V; Chubukina, Zh V; Buĭniakova, A I; Zimin, A A

    2012-01-01

    The immunological rehabilitation of the patients with oncological problems after the completion of standard anti-tumour therapy remains a topical problem in modern medicine. The up-to-date phototherapeutic methods find the increasingly wider application for the treatment of such patients including the use of monochromatic visible (VIS) and near infrared (nIR) radiation emitted from lasers and photodiodes. The objective of the present study was to substantiate the expediency of postoperative immune rehabilitation of the patients with breast cancer (BC) by means of irradiation of the body surface with polychromatic visible (pVIS) in combination with polychromatic infrared (pIR) light similar to the natural solar radiation without its minor UV component. The study included 19 patients with stage I--II BC at the mean age of 54.0 +/- 4.28 years having the infiltrative-ductal form of the tumour who had undergone mastectomy. These patients were randomly allocated to two groups, one given the standard course of postoperative rehabilitation (control), the other (study group) additionally treated with pVIS + pIR radiation applied to the lumbar-sacral region from days 1 to 7 after surgery. A Bioptron-2 phototherapeutic device, Switzerland, was used for the purpose (480-3400 nm, 40 mW/cm2, 12 J/cm2, with the light spot diameter of 15 cm). The modern standard immunological methods were employed. It was found that mastectomy induced changes of many characteristics of cellular and humoral immunity; many of them in different patients were oppositely directed. These changes were apparent within the first 7 days postoperatively. The course of phototherapy (PT) was shown to prevent the postoperative decrease in the counts of monocytes and natural killer (NK) cells, the total amount of CD3+ -T-lymphocytes (LPC), CD4+ -T-helpers, activated T-lymphocytes (CD3+ HLA-DR+ cells) and IgA levels as well as intracellular digestion rate of neutrophil-phagocyted bacteria. Moreover PT promoted

  5. Novel radiation sources using relativistic electrons from infrared to x-rays

    CERN Document Server

    Rullhusen, P; Dhez, P

    1998-01-01

    The purpose of this book is to give a description of the state of the art in theoretical and experimental work achieved in radiation source development. It summarizes clearly and comprehensibly, the basic physical aspects needed to understand the phenomena, and also provides the interested reader with sufficient literature to be able to follow the development in more detail. In addition, it contains a unified view of most theoretical effects and their common properties. The most recent developments as well as references to further work can be found in this volume. In many cases, review article

  6. Infrared spectroscopic study of radiation-induced adsorption of n-hexane on a beryllium surface

    Science.gov (United States)

    Gadzhieva, N. N.

    2017-07-01

    Radiation-stimulated adsorption on a beryllium surface is studied by IR reflection-absorption spectroscopy. It is found that γ-irradiation at room temperature leads to the appearance of n-hexane adsorption centers on a beryllium surface according to molecular and dissociation mechanisms. The kinetics of n-hexane adsorption in a Be- n-hexane system is studied; activated dissociative chemisorption accompanied by formation of beryllium alkyls and surface hydrides is observed at absorbed doses 15 kGy ≤ Vγ ≤ 35 kGy. A possible mechanism of this process is suggested.

  7. Modelling of atmospheric mid-infrared radiative transfer: the AMIL2DA algorithm intercomparison experiment

    International Nuclear Information System (INIS)

    Clarmann, T. von; Hoepfner, M.; Funke, B.; Lopez-Puertas, M.; Dudhia, A.; Jay, V.; Schreier, F.; Ridolfi, M.; Ceccherini, S.; Kerridge, B.J.; Reburn, J.; Siddans, R.

    2003-01-01

    When retrieving atmospheric parameters from radiance spectra, the forward modelling of radiative transfer through the Earth's atmosphere plays a key role, since inappropriate modelling directly maps on to the retrieved state parameters. In the context of pre-launch activities of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) experiment, which is a high resolution limb emission sounder for measurement of atmospheric composition and temperature, five scientific groups intercompared their forward models within the framework of the Advanced MIPAS Level 2 Data Analysis (AMIL2DA) project. These forward models have been developed, or, in certain respects, adapted in order to be used as part of the groups' MIPAS data processing. The following functionalities have been assessed: the calculation of line strengths including non-local thermodynamic equilibrium, the evaluation of the spectral line shape, application of chi-factors and semi-empirical continua, the interpolation of pre-tabulated absorption cross sections in pressure and temperature, line coupling, atmospheric ray tracing, the integration of the radiative transfer equation through an inhomogeneous atmosphere, the convolution of monochromatic spectra with an instrument line shape function, and the integration of the incoming radiances over the instrument field of view

  8. Effect of infrared radiation on the threshold behavior of scattering (and decay) processes

    International Nuclear Information System (INIS)

    Mohanty, A.K.; Rosenberg, L.; Spruch, L.

    1988-01-01

    An analysis is given of the effect of radiative corrections on the threshold behavior of the cross section for the inelastic scattering of a light charged particle by a neutral composite system. Explicit results are obtained for a model problem where the target consists of a proton and antiproton bound under their mutual Coulomb interaction and excited to a 2p state from its 1s ground state by electron impact, but the conclusions drawn are applicable, qualitatively, to a wide range of problems. It is found that when the energy resolution Δepsilon-c of the electron detector is small compared with the kinetic energy K' of the electron in the final state, the more careful treatment given here, which properly accounts for the rapid variation of the cross section for scattering energies near threshold, leads to only small modifications in the standard form of the radiative correction factor δ. For sufficiently high resolution in energy of a (high-energy) incident beam, the modification could be significant if Δepsilon-c is comparable with K'. The above considerations are applicable not only to scattering cross sections but to endpoints of the energy spectrum of the charged particle in a decay process in which only one charged particle is emitted

  9. White light emission from Er2O3 nano-powder excited by infrared radiation

    Science.gov (United States)

    Tabanli, Sevcan; Eryurek, Gonul; Di Bartolo, Baldassare

    2017-07-01

    Phosphors of Er2O3 nano-crystalline powders were synthesized by the thermal decomposition method. The structural properties of the nano-powders were investigated with XRD and HRTEM measurements. The cubic phase with a = 10.540 Å was the only phase observed. The average crystalline sizes and the widths of the grain size distribution curves were determined to be 27.2, 18.7 and 9.7 nm, respectively. The spectroscopic properties of the Er2O3 nano-powder were studied by measuring the luminescence, decay and rise patterns under 808 and 975 nm diode laser excitations. A peculiar effect of the pressure was observed since an optically active ion (Er) is part of the complex and not a dopant. A broad band of the white light emission combined with blue, green and red up-conversion emission bands of Er3+ ions were observed at 0.03 mbar pressure under both excitation wavelengths. Only, an intense broad band white light emission was observed from these nanocrystals at atmospheric pressure. Rising patterns show that the white light intensity reaches its maximum value more rapidly under 975 nm excitation although it decays slower than that of 808 nm excitation. The color quality parameters such as the color coordinate (CRI), correlated color temperature and the color rendering index were found to vary with both the excitation wavelength and the ambient pressure indicating that these nanocrystals could be considered good white light emitting source under the infrared excitations.

  10. Thermal energy harvesting near-infrared radiation and accessing low temperatures with plasmonic sensors.

    Science.gov (United States)

    Karker, Nicholas A; Dharmalingam, Gnanaprakash; Carpenter, Michael A

    2015-11-14

    Near-infrared (NIR) thermal energy harvesting has been demonstrated for gold nanorods (AuNRs), allowing concentration dependent, ppm-level, gas detection of H2, CO, and NO2 at 500 °C without using a white light source. Part-per-million detection capabilities of the gold nanorods are demonstrated with a factor of 11 reduction in collection times in the NIR as compared to measurements made in the visible light region. Decreased collection times are enabled by an increase in S : N ratio, which allowed a demonstration of selectivity through the use of both full spectral and a reduced spectral-based principal component analysis. Furthermore, low temperature thermal imaging spectra have been obtained at sample temperatures ranging from 275-500 °C, showing the possibility of energy harvested gas sensing at lower temperatures. These findings are promising in the area of miniaturizing plasmonic gas sensing technology and integration in areas such as gas turbines.

  11. Ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance and their application on energy-saving kettle

    Science.gov (United States)

    Zhang, Jianyi; Fan, Xi'an; Lu, Lei; Hu, Xiaoming; Li, Guangqiang

    2015-07-01

    Starting from Fe2O3, MnO2, Co2O3 and NiO powders, the ferrites based infrared radiation coatings with high emissivity and high thermal shock resistance were successfully prepared on the surface of carbon steel by high velocity oxy-fuel spraying (HVOF). The coating thickness was about 120-150 μm and presented a typical flat lamellar structure. The coating surface was rough and some submicron grade grains distributed on it. The infrared emissivity of the ferrites based coating by HVOF was over 0.74 in 3-20 μm waveband at 800 °C, which was obviously higher than that of the coating by brushing process in the short waveband. The bonding strength was 30.7 MPa between the coating and substrate, which was five times more than that of conventional coatings by brushing process. The combined effect of the superior bonding strength, typical lamellar structure, pre-existing microcracks and newly generated pores made the cycle times reach 27 when the coating samples were quenched from 1000 °C using water. Lastly, the infrared radiation coatings were applied on the underside of household kettle, and the energy-saving efficiency could reach 30.5%. The ferrites based infrared radiation coatings obtained in this work are good candidates for saving energy in the field of cookware and industrial high temperature furnace.

  12. A fast radiative transfer model for visible through shortwave infrared spectral reflectances in clear and cloudy atmospheres

    International Nuclear Information System (INIS)

    Wang, Chenxi; Yang, Ping; Nasiri, Shaima L.; Platnick, Steven; Baum, Bryan A.; Heidinger, Andrew K.; Liu, Xu

    2013-01-01

    A computationally efficient radiative transfer model (RTM) for calculating visible (VIS) through shortwave infrared (SWIR) reflectances is developed for use in satellite and airborne cloud property retrievals. The full radiative transfer equation (RTE) for combinations of cloud, aerosol, and molecular layers is solved approximately by using six independent RTEs that assume the plane-parallel approximation along with a single-scattering approximation for Rayleigh scattering. Each of the six RTEs can be solved analytically if the bidirectional reflectance/transmittance distribution functions (BRDF/BTDF) of the cloud/aerosol layers are known. The adding/doubling (AD) algorithm is employed to account for overlapped cloud/aerosol layers and non-Lambertian surfaces. Two approaches are used to mitigate the significant computational burden of the AD algorithm. First, the BRDF and BTDF of single cloud/aerosol layers are pre-computed using the discrete ordinates radiative transfer program (DISORT) implemented with 128 streams, and second, the required integral in the AD algorithm is numerically implemented on a twisted icosahedral mesh. A concise surface BRDF simulator associated with the MODIS land surface product (MCD43) is merged into a fast RTM to accurately account for non-isotropic surface reflectance. The resulting fast RTM is evaluated with respect to its computational accuracy and efficiency. The simulation bias between DISORT and the fast RTM is large (e.g., relative error >5%) only when both the solar zenith angle (SZA) and the viewing zenith angle (VZA) are large (i.e., SZA>45° and VZA>70°). For general situations, i.e., cloud/aerosol layers above a non-Lambertian surface, the fast RTM calculation rate is faster than that of the 128-stream DISORT by approximately two orders of magnitude. -- Highlights: ► An efficient radiative transfer model is developed for cloud remote sensing. ► Multi-layered clouds and a non-Lambertian surface can be fully considered.

  13. Accounting for particle non-sphericity in modeling of mineral dust radiative properties in the thermal infrared

    International Nuclear Information System (INIS)

    Legrand, M.; Dubovik, O.; Lapyonok, T.; Derimian, Y.

    2014-01-01

    Spectral radiative parameters (extinction optical depth, single scattering albedo, asymmetry factor) of spheroids of mineral dust composed of quartz and clays have been simulated at wavelengths between 7.0 and 10.2 µm using a T-matrix code. In spectral intervals with high values of complex index of refraction and for large particles, the parameters cannot be fully calculated with the code. Practically, the calculations are stopped at a truncation radius over which the particles contribution cannot thus be taken into account. To deal with this issue, we have developed and applied an accurate corrective technique of T-matrix Size Truncation Compensation (TSTC). For a mineral dust described by its AERONET standard aspect ratio (AR) distribution, the full error margin when applying the TSTC is within 0.3% (or ±0.15%), whatever the radiative parameter and the wavelength considered, for quartz (the most difficult case). Large AR values limit also the possibilities of calculation with the code. The TSTC has been able to complete the calculations of the T-matrix code for a modified AERONET AR distribution with a maximum AR of 4.7 instead of 3 for the standard distribution. Comparison between the simulated properties of spheroids and of spheres of same volume confirms, in agreement with the literature, that significant differences are observed in the vicinity of the mineral resonant peaks (λ ca. 8.3–8.7 µm for quartz, ca. 9.3–9.5 µm for clays) and that they are due to absorption by the small particles. This is a favorable circumstance for the TSTC, which is concerned with the contribution of the largest particles. This technique of numerical calculation improves the accuracy of the simulated radiative parameters of mineral dust, which must lead to a progress in view of applications such as remote sensing or determination of energy balance of dust in the thermal infrared (TIR), incompletely investigated so far. - Highlights: • Completion of computation of mineral

  14. Supra-threshold epidermis injury from near-infrared laser radiation prior to ablation onset

    Science.gov (United States)

    DeLisi, Michael P.; Peterson, Amanda M.; Lile, Lily A.; Noojin, Gary D.; Shingledecker, Aurora D.; Stolarski, David J.; Zohner, Justin J.; Kumru, Semih S.; Thomas, Robert J.

    2017-02-01

    With continued advancement of solid-state laser technology, high-energy lasers operating in the near-infrared (NIR) band are being applied in an increasing number of manufacturing techniques and medical treatments. Safety-related investigations of potentially harmful laser interaction with skin are commonplace, consisting of establishing the maximum permissible exposure (MPE) thresholds under various conditions, often utilizing the minimally-visible lesion (MVL) metric as an indication of damage. Likewise, characterization of ablation onset and velocity is of interest for therapeutic and surgical use, and concerns exceptionally high irradiance levels. However, skin injury response between these two exposure ranges is not well understood. This study utilized a 1070-nm Yb-doped, diode-pumped fiber laser to explore the response of excised porcine skin tissue to high-energy exposures within the supra-threshold injury region without inducing ablation. Concurrent high-speed videography was employed to assess the effect on the epidermis, with a dichotomous response determination given for three progressive damage event categories: observable permanent distortion on the surface, formation of an epidermal bubble due to bounded intra-cutaneous water vaporization, and rupture of said bubble during laser exposure. ED50 values were calculated for these categories under various pulse configurations and beam diameters, and logistic regression models predicted injury events with approximately 90% accuracy. The distinction of skin response into categories of increasing degrees of damage expands the current understanding of high-energy laser safety while also underlining the unique biophysical effects during induced water phase change in tissue. These observations could prove useful in augmenting biothermomechanical models of laser exposure in the supra-threshold region.

  15. Strong control and squeezing effects of radiation states in a slab waveguide sandwiched between two omnidirectional mirrors

    NARCIS (Netherlands)

    van Driel, H.M.; Hoekstra, Hugo; Stoffer, Remco; Yudistira, D.

    The effect of sandwiching a slab waveguide in air between two omnidirectional mirrors on the local density of modes is investigated theoretically. Design aspects of such a structure are considered, and it is shown that the local density of modes other than the slab-guided mode can be strongly

  16. Radio-oxidation of an EPDM elastomer under weak or strong ionising radiations: measurement and modelling of dioxygen consumption

    International Nuclear Information System (INIS)

    Dely, N.

    2005-10-01

    Usually, the irradiation of polymers under ionising radiations occurs in air that is in the presence of oxygen. This leads to a radio oxidation process and to oxygen consumption. Our material is an EPDM elastomer (ethylene propylene 1,4 hexadiene) used as insulator in control-command cables in nuclear plants (Pressurised Water Reactor). A specific device has been conceived and built up during this PhD work for measuring very small oxygen consumptions with an accuracy of around 10%. Ionising radiations used are electrons at 1 MeV and carbon ions at 11 MeV per nucleon. Under both electron and ion irradiations, the influence of oxygen pressure on oxygen consumption has been studied in a very large range: between 1 and 200 mbar. In both cases, the yield of oxygen consumption is constant in-between 200 and 5 mbar. Then, at lower pressures, it decreases appreciably. On the other hand, the oxygen consumption during ion irradiation is four times smaller than during electron irradiation. This emphasizes the role of the heterogeneity of the energy deposition at a nano-metric scale. The adjustment of the experimental results obtained during electron irradiation with the general homogeneous steady-state kinetic model has allowed extracting all the values of the kinetic parameters for the chosen mechanism of radio oxidation. The knowledge of these numbers will allow us to face our results obtained during ion irradiation with a heterogeneous kinetic model under development. (author)

  17. SHARC, a model for calculating atmospheric and infrared radiation under non-equilibrium conditions

    Science.gov (United States)

    Sundberg, R. L.; Duff, J. W.; Gruninger, J. H.; Bernstein, L. S.; Sharma, R. D.

    1994-01-01

    A new computer model, SHARC, has been developed by the Air Force for calculating high-altitude atmospheric IR radiance and transmittance spectra with a resolution of better than 1/cm. Comprehensive coverage of the 2 to 40 microns (250/cm to 5,000/cm) wavelength region is provided for arbitrary lines of sight in the 50-300 km altitude regime. SHARC accounts for the deviation from local thermodynamic equilibrium (LTE) in vibrational state populations by explicitly modeling the detailed production, loss, and energy transfer process among the important molecular vibrational states. The calculated vibrational populations are found to be similar to those obtained from other non-LTE codes. The radiation transport algorithm is based on a single-line equivalent width approximation along with a statistical correction for line overlap. This approach is reasonably accurate for most applications and is roughly two orders of magnitude faster than the traditional LBL methods which explicitly integrate over individual line shapes. In addition to quiescent atmospheric processes, this model calculates the auroral production and excitation of CO2, NO, and NO(+) in localized regions of the atmosphere. Illustrative comparisons of SHARC predictions to other models and to data from the CIRRIS, SPIRE, and FWI field experiments are presented.

  18. SHARC, a model for calculating atmospheric infrared radiation under non-equilibrium conditions

    Science.gov (United States)

    Sundberg, R. L.; Duff, J. W.; Gruninger, J. H.; Bernstein, L. S.; Matthew, M. W.; Adler-Golden, S. M.; Robertson, D. C.; Sharma, R. D.; Brown, J. H.; Healey, R. J.

    A new computer model, SHARC, has been developed by the U.S. Air Force for calculating high-altitude atmospheric IR radiance and transmittance spectra with a resolution of better than 1 cm 4. Comprehensive coverage of the 2 to 40 μm (250 to 5,000 cm-1) wavelength region is provided for arbitrary lines of sight in the 50-300 km altitude regime. SHARC accounts for the deviation from local thermodynamic equilibrium (LTE) in state populations by explicitly modeling the detailed production, loss, and energy transfer processes among the contributing molecular vibrational states. The calculated vibrational populations are found to be similar to those obtained from other non-LTE codes. The radiation transport algorithm is based on a single-line equivalent width approximation along with a statistical correction for line overlap. This approach calculates LOS radiance values which are accurate to ±10% and is roughly two orders of magnitude faster than the traditional LBL methods which explicitly integrate over individual line shapes. In addition to quiescent atmospheric processes, this model calculates the auroral production and excitation of CO2, NO, and NO+ in localized regions of the atmosphere. Illustrative comparisons of SHARC predictions to other models and to data from the CIRRIS, SPIRE and FWI field experiments are presented.

  19. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Self-pumped passive ring mirror in crystals with strong fanning

    Science.gov (United States)

    Bogodaev, N. V.; Zozulya, A. A.; Ivleva, Lyudmila I.; Korshunov, A. S.; Mamaev, A. V.; Polozkov, N. M.

    1992-05-01

    Most photorefractive crystals suitable for four-wave systems of phase self-conjugation and mutual conjugation have a fairly high level of light-induced scattering (fanning). This may imply that the nonlinearity of a crystal is too strong for optimal operation and a reduction in this nonlinearity would improve the characteristics. This statement is illustrated theoretically and experimentally using the geometry of a loop parametric oscillator as an example.

  20. Analysis of peripheral thermal damage after laser irradiation of dentin using polarized light microscopy and synchrotron radiation infrared spectromicroscopy

    Science.gov (United States)

    Dela Rosa, Alfredo; Sarma, Anupama V.; Le, Charles Q.; Jones, Robert S.; Fried, Daniel

    2004-05-01

    It is necessary to minimize peripheral thermal damage during laser irradiation, since thermal damage to collagen and mineral compromises the bond strength to restorative materials in dentin and inhibits healing and osteointegration in bone. The overall objective of this study was to test the hypothesis that lasers resonant to the specific absorption of water, collagen, and hydroxyapatite with pulse durations less than the thermal relaxation times at each respective laser wavelength will efficiently remove dentin with minimal peripheral thermal damage. Precise incisions were produced in 3 x 3 mm2 blocks of human dentin using CO2 (9.6 μm), Er:YSGG (2.79 μm), and Nd:YAG (355 nm) lasers with and without a computer controlled water spray. Polarization-sensitive optical coherence tomography was used to obtain optical cross-sections of each incision to determine the rate and efficiency of ablation. The peripheral thermal damage zone around each incision was analyzed using polarized light microscopy (PLM) and Synchrotron-Radiation Fourier Transform Infrared Spectro-microscopy (SR-FTIR). Thermally induced chemical changes to both mineral and the collagen matrix was observed with SR-FTIR with a 10-μm spatial resolution and those changes were correlated with optical changes observed with PLM. Minimal (alveolar bone.

  1. Effects of Combined Far-Infrared Radiation and Acupuncture at ST36 on Peripheral Blood Perfusion and Autonomic Activities

    Directory of Open Access Journals (Sweden)

    Cheng-Chan Yang

    2017-01-01

    Full Text Available Using four-channel photoplethysmography (PPG for acquiring peripheral arterial waveforms, this study investigated vascular and autonomic impacts of combined acupuncture-far infrared radiation (FIR in improving peripheral circulation. Twenty healthy young adults aged 25.5±4.6 were enrolled for 30-minute measurement. Each subject underwent four treatment strategies, including acupuncture at ST36 (Zusanli, pseudoacupuncture, FIR, and combined acupuncture-FIR at different time points. Response was assessed at 5-minute intervals. Area under arterial waveform at baseline was defined as AreaBaseline, whereas AreaStim referred to area at each 5-minute substage during and after treatment. AreaStim/AreaBaseline was compared at different stages and among different strategies. Autonomic activity at different stages was assessed using low-to-high frequency power ratio (LHR. The results demonstrated increased perfusion for each therapeutic strategy from stage 1 to stage 2 (all p<0.02. Elevated perfusion was noted for all treatment strategies at stage 3 compared to stage 1 except pseudoacupuncture. Increased LHR was noted only in subjects undergoing pseudoacupuncture at stage 3 compared to stage 1 (p=0.045. Reduced LHR at stage 2 compared to stage 1 was found only in combined treatment group (p=0.041. In conclusion, the results support clinical benefits of combined acupuncture-FIR treatment in enhancing peripheral perfusion and parasympathetic activity.

  2. Detection of an Inner Gaseous Component in a Herbig Be Star Accretion Disk: Near- and Mid-Infrared Spectrointerferometry and Radiative Transfer modeling of MWC 147

    Science.gov (United States)

    Kraus, Stefan; Preibisch, Thomas; Ohnaka, Keiichi

    2008-03-01

    We study the geometry and the physical conditions in the inner (AU-scale) circumstellar region around the young Herbig Be star MWC 147 using long-baseline spectrointerferometry in the near-infrared (NIR) K-band, VLTI/AMBER observations, and PTI archive data, as well as the mid-infrared (MIR) N-band, VLTI/MIDI observations. The emission from MWC 147 is clearly resolved and has a characteristic physical size of ~1.3 and ~9 AU at 2.2 and 11 μm, respectively (Gaussian diameter). The MIR emission reveals asymmetry consistent with a disk structure seen under intermediate inclination. The spectrally dispersed AMBER and MIDI interferograms both show a strong increase in the characteristic size toward longer wavelengths, much steeper than predicted by analytic disk models assuming power-law radial temperature distributions. We model the interferometric data and the spectral energy distribution of MWC 147 with two-dimensional, frequency-dependent radiation transfer simulations. This analysis shows that models of spherical envelopes or passive irradiated Keplerian disks (with vertical or curved puffed-up inner rim) can easily fit the SED, but predict much lower visibilities than observed; the angular size predicted by such models is 2-4 times larger than the size derived from the interferometric data, so these models can clearly be ruled out. Models of a Keplerian disk with optically thick gas emission from an active gaseous disk (inside the dust sublimation zone), however, yield a good fit of the SED and simultaneously reproduce the absolute level and the spectral dependence of the NIR and MIR visibilities. We conclude that the NIR continuum emission from MWC 147 is dominated by accretion luminosity emerging from an optically thick inner gaseous disk, while the MIR emission also contains contributions from the outer, irradiated dust disk. Based on observations made with ESO telescopes at the La Silla Paranal Observatory under program IDs 074.C-0181, 076.C-0138, and 078.C

  3. Observation of the ion-acoustic feature in the spectrum of far-infrared radiation scattered from a He-plasma in a tokamak

    International Nuclear Information System (INIS)

    Salito, S.A.; Siegrist, M.R.; Behn, R.; Dicken, D.; Hackmann, J.

    1989-01-01

    The ion-acoustic feature in the spectrum of a He plasma produced in a tokamak has been observed by collective Thomson scattering of far-infrared radiation. The spectral distribution and the intensity of the scattered radiation correspond to density fluctuations at the thermal level. Since the resonant feature is very sensitive to the ratio T e /T i , good precision of a T i measurement can be obtained when T e is known. The results confirm the interpretation of earlier measurements in H and D plasmas. (author) 4 figs., 1 tab., 3 refs

  4. Analysis by Fourier Transform Infrared (FTIR) of the gamma radiation effect on epoxy resin, used as solidification agent of radioactive wastes

    International Nuclear Information System (INIS)

    Liu, C.H.; Riella, H.G.; Guedes, S.M.L.

    1995-01-01

    The effects of gamma radiation on Epoxy resin, used as solidification agent of radioactive wastes, were studied by Fourier Transform Infrared (FTIR). The spectra showed no significant modifications on Epoxy resin functional groups (irradiated with dose from 0 to 1 MGy). Up to 1 MGy Epoxy resin did not oxidize, confirming the Epoxy good radiation strength. The presence of aromatic chain and amine group, mainly tertiary amine, give good radiolytic stability to the Epoxy, increasing the interest to use this material in nuclear facilities. (author). 3 refs, 2 figs

  5. Single-footprint retrievals for AIRS using a fast TwoSlab cloud-representation model and the SARTA all-sky infrared radiative transfer algorithm

    Directory of Open Access Journals (Sweden)

    S. DeSouza-Machado

    2018-01-01

    Full Text Available One-dimensional variational retrievals of temperature and moisture fields from hyperspectral infrared (IR satellite sounders use cloud-cleared radiances (CCRs as their observation. These derived observations allow the use of clear-sky-only radiative transfer in the inversion for geophysical variables but at reduced spatial resolution compared to the native sounder observations. Cloud clearing can introduce various errors, although scenes with large errors can be identified and ignored. Information content studies show that, when using multilayer cloud liquid and ice profiles in infrared hyperspectral radiative transfer codes, there are typically only 2–4 degrees of freedom (DOFs of cloud signal. This implies a simplified cloud representation is sufficient for some applications which need accurate radiative transfer. Here we describe a single-footprint retrieval approach for clear and cloudy conditions, which uses the thermodynamic and cloud fields from numerical weather prediction (NWP models as a first guess, together with a simple cloud-representation model coupled to a fast scattering radiative transfer algorithm (RTA. The NWP model thermodynamic and cloud profiles are first co-located to the observations, after which the N-level cloud profiles are converted to two slab clouds (TwoSlab; typically one for ice and one for water clouds. From these, one run of our fast cloud-representation model allows an improvement of the a priori cloud state by comparing the observed and model-simulated radiances in the thermal window channels. The retrieval yield is over 90 %, while the degrees of freedom correlate with the observed window channel brightness temperature (BT which itself depends on the cloud optical depth. The cloud-representation and scattering package is benchmarked against radiances computed using a maximum random overlap (RMO cloud scheme. All-sky infrared radiances measured by NASA's Atmospheric Infrared Sounder (AIRS and NWP

  6. Single-footprint retrievals for AIRS using a fast TwoSlab cloud-representation model and the SARTA all-sky infrared radiative transfer algorithm

    Science.gov (United States)

    DeSouza-Machado, Sergio; Larrabee Strow, L.; Tangborn, Andrew; Huang, Xianglei; Chen, Xiuhong; Liu, Xu; Wu, Wan; Yang, Qiguang

    2018-01-01

    One-dimensional variational retrievals of temperature and moisture fields from hyperspectral infrared (IR) satellite sounders use cloud-cleared radiances (CCRs) as their observation. These derived observations allow the use of clear-sky-only radiative transfer in the inversion for geophysical variables but at reduced spatial resolution compared to the native sounder observations. Cloud clearing can introduce various errors, although scenes with large errors can be identified and ignored. Information content studies show that, when using multilayer cloud liquid and ice profiles in infrared hyperspectral radiative transfer codes, there are typically only 2-4 degrees of freedom (DOFs) of cloud signal. This implies a simplified cloud representation is sufficient for some applications which need accurate radiative transfer. Here we describe a single-footprint retrieval approach for clear and cloudy conditions, which uses the thermodynamic and cloud fields from numerical weather prediction (NWP) models as a first guess, together with a simple cloud-representation model coupled to a fast scattering radiative transfer algorithm (RTA). The NWP model thermodynamic and cloud profiles are first co-located to the observations, after which the N-level cloud profiles are converted to two slab clouds (TwoSlab; typically one for ice and one for water clouds). From these, one run of our fast cloud-representation model allows an improvement of the a priori cloud state by comparing the observed and model-simulated radiances in the thermal window channels. The retrieval yield is over 90 %, while the degrees of freedom correlate with the observed window channel brightness temperature (BT) which itself depends on the cloud optical depth. The cloud-representation and scattering package is benchmarked against radiances computed using a maximum random overlap (RMO) cloud scheme. All-sky infrared radiances measured by NASA's Atmospheric Infrared Sounder (AIRS) and NWP thermodynamic and cloud

  7. Infrared and dc conductivity in metals with strong scattering: Nonclassical behavior from a generalized Boltzmann equation containing band-mixing effects

    International Nuclear Information System (INIS)

    Allen, P.B.; Chakraborty, B.

    1981-01-01

    Metals with high resistivity (approx.100 μΩ cm) seem to show weaker variation of resistivity (as a function of temperature and perhaps also static disorder) than predicted by semiclassical (Bloch-Boltzmann) theory (SBT). We argue that the effect is not closely related to Anderson localization, and therefore does not necessarily signify a failure of the independent collision approximation. Instead we propose a failure of the semiclassical acceleration and conduction approximations. A generalization of Boltzmann theory is made which includes quantum (interband) acceleration and conduction, as well as a complete treatment of interband-collision effects (within the independent-collision approximation). The interband terms enhance short-time response to E fields (because the theory satisfies the exact f-sum rule instead of the semiclassical approximation to it). This suggests that the additional conductivity, as expressed phenomenologically by the shunt resistor model, is explained by interband effects. The scattering operator is complex, its imaginary parts being related to energy-band renormalization caused by the disorder. Charge conservation is respected and thermal equilibrium is restored by the collision operator. The theory is formally solved for the leading corrections to SBT, which have the form of a shunt resistor model. At infrared frequencies, the conductivity mostly obeys the Drude law sigma(ω)approx.sigma(0)(1-iωtau) -1 , except for one term which goes as (1-iωtau) -2

  8. Strong optical-mechanical coupling in a vertical GaAs/AlAs microcavity for subterahertz phonons and near-infrared light.

    Science.gov (United States)

    Fainstein, A; Lanzillotti-Kimura, N D; Jusserand, B; Perrin, B

    2013-01-18

    We show that distributed Bragg reflector GaAs/AlAs vertical cavities designed to confine photons are automatically optimal to confine phonons of the same wavelength, strongly enhancing their interaction. We study the impulsive generation of intense coherent and monochromatic acoustic phonons by following the time evolution of the elastic strain in picosecond-laser experiments. Efficient optical detection is assured by the strong phonon backaction on the high-Q optical cavity mode. Large optomechanical factors are reported (~THz/nm range). Pillar cavities based in these structures are predicted to display picogram effective masses, almost perfect sound extraction, and threshold powers for the stimulated emission of phonons in the range μW-mW, opening the way for the demonstration of phonon "lasing" by parametric instability in these devices.

  9. Cu₂-xSe@mSiO₂-PEG core-shell nanoparticles: a low-toxic and efficient difunctional nanoplatform for chemo-photothermal therapy under near infrared light radiation with a safe power density.

    Science.gov (United States)

    Liu, Xijian; Wang, Qian; Li, Chun; Zou, Rujia; Li, Bo; Song, Guosheng; Xu, Kaibing; Zheng, Yun; Hu, Junqing

    2014-04-21

    A low-toxic difunctional nanoplatform integrating both photothermal therapy and chemotherapy for killing cancer cells using Cu₂-xSe@mSiO₂-PEG core-shell nanoparticles is reported. Silica coating and further PEG modification improve the hydrophilicity and biocompatibility of copper selenide nanoparticles. As-prepared Cu₂-xSe@mSiO₂-PEG nanoparticles not only display strong near infrared (NIR) region absorption and good photothermal effect, but also exhibit excellent biocompatibility. The mesoporous silica shell is provided as the carrier for loading the anticancer drug, doxorubicin (DOX). Moreover, the release of DOX from Cu₂-xSe@mSiO₂-PEG core-shell nanoparticles can be triggered by pH and NIR light, resulting in a synergistic effect for killing cancer cells. Importantly, the combination of photothermal therapy and chemotherapy driven by NIR radiation with safe power density significantly improves the therapeutic efficacy, and demonstrates better therapeutic effects for cancer treatment than individual therapy.

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

    International Nuclear Information System (INIS)

    Evora, Maria Cecilia; Goncalez, Odair Lelis

    2000-01-01

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

  11. Radiative transfer modeling of dust-coated Pancam calibration target materials: Laboratory visible/near-infrared spectrogoniometry

    Science.gov (United States)

    Johnson, J. R.; Sohl-Dickstein, J.; Grundy, W.M.; Arvidson, R. E.; Bell, J.F.; Christensen, P.R.; Graff, T.; Guinness, E.A.; Kinch, K.; Morris, Robert; Shepard, M.K.

    2006-01-01

    Laboratory visible/near-infrared multispectral observations of Mars Exploration Rover Pancam calibration target materials coated with different thicknesses of Mars spectral analog dust were acquired under variable illumination geometries using the Bloomsburg University Goniometer. The data were fit with a two-layer radiative transfer model that combines a Hapke formulation for the dust with measured values of the substrate interpolated using a He-Torrance approach. We first determined the single-scattering albedo, phase function, opposition effect width, and amplitude for the dust using the entire data set (six coating thicknesses, three substrates, four wavelengths, and phase angles 3??-117??). The dust exhibited single-scattering albedo values similar to other Mars analog soils and to Mars Pathfinder dust and a dominantly forward scattering behavior whose scattering lobe became narrower at longer wavelengths. Opacity values for each dust thickness corresponded well to those predicted from the particles sizes of the Mars analog dust. We then restricted the number of substrates, dust thicknesses, and incidence angles input to the model. The results suggest that the dust properties are best characterized when using substrates whose reflectances are brighter and darker than those of the deposited dust and data that span a wide range of dust thicknesses. The model also determined the dust photometric properties relatively well despite limitations placed on the range of incidence angles. The model presented here will help determine the photometric properties of dust deposited on the MER rovers and to track the multiple episodes of dust deposition and erosion that have occurred at both landing sites. Copyright 2006 by the American Geophysical Union.

  12. The use of ultrasound and infrared radiation to reduce microbiological contamination of raw materials in the production of citric acid

    International Nuclear Information System (INIS)

    Sharova, N.Yu.; Kamen'kova, N.V.

    2012-01-01

    The microflora of the main raw materials for producing citric acid (beet molasses and grain) is capable of greatly reducing the yield of target metabolite or changing the focus of biosynthesis. Rye, oats and barley grain with humidity of 16% and its grinds (a particle size 1 mm) was treated ultrasound having a capacity of 1.5 kW, frequency 15 and 22 kHz. Infrared radiation treatment was carried out at t 120 to 180 degrees C for 2-30 min and the exposure power W/sq. cm. In molasses there were found spore-forming heat-resistant bacteria with Bacillus subtilis and B. mesentericus being predominated, gaseous, nitrite-forming, acid-forming bacteria, yeast of gen. Candida, Leuconostoc mesenteroides that consume sugar, nitric and mineral substances reducing the biosynthetic activity of Aspergillus niger producer. For molasses treated with ultrasound 1.5 kW and frequency 22 kHz, the total viable count reduces by the order compared to the control. Increasing the exposure time up to 30 min results in slightly reducing the achieved level. Under influence of ultrasound the contamination with bacteria and mold fungi of rye, oats and barley grain grinds reduces by 2-3 orders compared to the control and much more at frequency 22 kHz. The great increase in the parameter of the total viable count is achieved by IR-treatment of grain and grinds. The microflora practically entirely dies by increasing the temperature up to 160-180 degrees C even in case of 2 minute exposure. IR treatment providing t 120 degrees C for 2-6 min resulted in reducing the number of cells of microorganisms by 3-4 orders compared to the untreated control

  13. Strong far-infrared intersubband absorption under normal incidence in heavily n-type doped nonalloy GaSb-AlSb superlattices

    Science.gov (United States)

    Samoska, L. A.; Brar, Berinder; Kroemer, H.

    1993-01-01

    We report on long-wavelength intersubband absorption under normal incidence in heavily doped binary-binary GaSb-AlSb superlattices. Due to a small energy difference between the ellipsoidal L valleys in GaSb and the low-density-of-states Gamma minimum, electrons spill over from the first Gamma subband into the higher-energy L subband in GaSb wells, where they are allowed to make an intersubband transition under normally incident radiation. A peak fractional absorption per quantum well of 6.8 x 10 exp 3 (absorption coefficient alpha of about 8500/cm) is observed at about 15 microns wavelength for a sheet concentration of 1.6 x 10 exp 12 sq cm/well.

  14. Seagrass radiation after Messinian salinity crisis reflected by strong genetic structuring and out-of-Africa scenario (Ruppiaceae.

    Directory of Open Access Journals (Sweden)

    Ludwig Triest

    Full Text Available Many aquatic plant and seagrass species are widespread and the origin of their continent-wide ranges might result from high gene flow levels. The response of species when extending northwards since the Last Glacial Maximum can be opposed to the structuring of their populations that survived glaciation cycles in southern regions. The peri-Mediterranean is a complex series of sea basins, coastlines, islands and river deltas with a unique history since the Messinian Crisis that potentially influenced allopatric processes of aquatic life. We tested whether vast ranges across Europe and the peri-Mediterranean of a global seagrass group (Ruppia species complexes can be explained by either overall high levels of gene flow or vicariance through linking population genetics, phylogeography and shallow phylogenetics. A multigene approach identified haplogroup lineages of two species complexes, of ancient and recent hybrids with most of the diversity residing in the South. High levels of connectivity over long distances were only observed at recently colonized northern ranges and in recently-filled seas following the last glaciation. A strong substructure in the southern Mediterranean explained an isolation-by-distance model across Europe. The oldest lineages of the southern Mediterranean Ruppia dated back to the period between the end of the Messinian and Late Pliocene. An imprint of ancient allopatric origin was left at basin level, including basal African lineages. Thus both vicariance in the South and high levels of connectivity in the North explained vast species ranges. Our findings highlight the need for interpreting global distributions of these seagrass and euryhaline species in the context of their origin and evolutionary significant units for setting up appropriate conservation strategies.

  15. Ultraviolet and infrared spectral analysis of poly(vinyl)butyral films: correlation and possible application for high-dose radiation dosimetry

    International Nuclear Information System (INIS)

    Ebraheem, S.; El-Kelany, M.; Beshir, W.; Abdel-Fattah, A.A.

    1999-01-01

    A detailed study was performed to develop the dosimetric characteristics of poly(vinyl)butyral film (PVB), to be used as a film dosimeter for high-dose gamma radiation dosimetry. The useful dose range of this polymeric film extends up to 350 kGy. Correlations were established between the absorbed dose of gamma radiation and the radiation-induced changes in PVB measured by means of ultraviolet (UV) and Fourier Transform Infrared (FTIR) spectrophotometry. The results showed a significant dependence of the response on the selected readout tool of measurements whether FTIR (at 1738 and 3400 cm -1 ) or UV (at 275 and 230 nm), as well as on the quantity used for calculation. The effect of relative humidity during irradiation on dosimeter performance as well as the post-irradiation stability at different storage conditions are also discussed. (author)

  16. Effective photoprotection of human skin against infrared A radiation by topically applied antioxidants: results from a vehicle controlled, double-blind, randomized study.

    Science.gov (United States)

    Grether-Beck, Susanne; Marini, Alessandra; Jaenicke, Thomas; Krutmann, Jean

    2015-01-01

    Infrared A radiation (IRA) from solar sunlight contributes to photoaging of human skin, e.g. by upregulating MMP-1 expression in dermal fibroblasts, indicating the need for photoprotection of human skin against IRA. Up to now, however, there has been no controlled study to show that effective protection of human skin against IRA radiation is possible. Here, we have conducted a randomized, controlled, double-blinded prospective study in 30 healthy volunteers to assess the capacity of an SPF 30 sunscreen versus the same sunscreen supplemented with an antioxidant cocktail containing grape seed extract, vitamin E, ubiquinone and vitamin C to protect human skin against IRA radiation-induced MMP-1 upregulation. As expected, exposure to IRA radiation significantly upregulated MMP-1 expression, as compared to unirradiated skin, and this response was significantly reduced, if the SPF30 sunscreen plus the antioxidant cocktail had been applied prior to IRA radiation. In contrast, treatment of human skin with the SPF30 sunscreen alone did not provide significant protection. These results indicate that topically applied antioxidants effectively protect human skin against IRA radiation and that regular sunscreens need to be supplemented with specific antioxidants in order to achieve IRA photoprotection. © 2014 The American Society of Photobiology.

  17. Acquisition of reproducible transmission near-infrared (NIR) spectra of solid samples with inconsistent shapes by irradiation with isotropically diffused radiation using polytetrafluoroethylene (PTFE) beads.

    Science.gov (United States)

    Lee, Jinah; Duy, Pham Khac; Yoon, Jihye; Chung, Hoeil

    2014-06-21

    A bead-incorporated transmission scheme (BITS) has been demonstrated for collecting reproducible transmission near-infrared (NIR) spectra of samples with inconsistent shapes. Isotropically diffused NIR radiation was applied around a sample and the surrounding radiation was allowed to interact homogeneously with the sample for transmission measurement. Samples were packed in 1.40 mm polytetrafluoroethylene (PTFE) beads, ideal diffusers without NIR absorption, and then transmission spectra were collected by illuminating the sample-containing beads using NIR radiation. When collimated radiation was directly applied, a small portion of the non-fully diffused radiation (NFDR) propagated through the void space of the packing and eventually degraded the reproducibility. Pre-diffused radiation was introduced by placing an additional PTFE disk in front of the packing to diminish NFDR, which produced more reproducible spectral features. The proposed scheme was evaluated by analyzing two different solid samples: density determination for individual polyethylene (PE) pellets and identification of mining locality for tourmalines. Because spectral collection was reproducible, the use of the spectrum acquired from one PE pellet was sufficient to accurately determine the density of nine other pellets with different shapes. The differentiation of tourmalines, which are even more dissimilar in appearance, according to their mining locality was also feasible with the help of the scheme.

  18. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  19. Microstructured thin film radiators as infrared sources for new gas measuring applications; Mikrostrukturierte Duennschichtstrahler als Infrarot-Strahlungsquellen fuer neue Anwendungen in der Gasmesstechnik

    Energy Technology Data Exchange (ETDEWEB)

    Vaihinger, S. [Endress und Hauser Conducta GmbH und Co., Gerlingen (Germany); Bytyn, W. [Endress und Hauser Conducta GmbH und Co., Gerlingen (Germany)

    1997-04-01

    Photometric infrared gas analysers for the low cost market are using directly modulated radiation. The mostly used glass encapsulated radiation sources are limiting the fields of application due to the absorption of the glass at wavelengths beyond 4.3 {mu}m. Microstructured thin film radiators enable new applications in the mid infrared range such as ammonia or Freon at 11 {mu}m. In addition these sources show better performance even in standard applications such as CO{sub 2} (4.24 {mu}m) at lower power consumption as compared with glass encapsulated sources. (orig.) [Deutsch] Photometrische Infrarot-Gasanalysatoren im Low-cost-Bereich arbeiten mit direkt modulierter Strahlung. Die meist verwendeten gasgekapselten Strahlungsquellen begrenzen den Anwendungsbereich durch die Transmissionseigenschaften des Glases, das fuer Infrarot nur bis 4,3 {mu}m durchlaessig ist. Mikrostrukturierte Duennschichtstrahler erschliessen nicht nur neue Anwendungen im laengerwelligen Bereich, wie z.B. Ammoniak oder Freon bei 11 {mu}m, sondern sie sind auch bei Standardanwendungen wie CO{sub 2} (4,24 {mu}m) bei deutlich geringerem Leistungsbedarf den einfachen Strahlern ueberlegen. (orig.)

  20. Ground squirrels use an infrared signal to deter rattlesnake predation.

    Science.gov (United States)

    Rundus, Aaron S; Owings, Donald H; Joshi, Sanjay S; Chinn, Erin; Giannini, Nicolas

    2007-09-04

    The evolution of communicative signals involves a major hurdle; signals need to effectively stimulate the sensory systems of their targets. Therefore, sensory specializations of target animals are important sources of selection on signal structure. Here we report the discovery of an animal signal that uses a previously unknown communicative modality, infrared radiation or "radiant heat," which capitalizes on the infrared sensory capabilities of the signal's target. California ground squirrels (Spermophilus beecheyi) add an infrared component to their snake-directed tail-flagging signals when confronting infrared-sensitive rattlesnakes (Crotalus oreganus), but tail flag without augmenting infrared emission when confronting infrared-insensitive gopher snakes (Pituophis melanoleucus). Experimental playbacks with a biorobotic squirrel model reveal this signal's communicative function. When the infrared component was added to the tail flagging display of the robotic models, rattlesnakes exhibited a greater shift from predatory to defensive behavior than during control trials in which tail flagging included no infrared component. These findings provide exceptionally strong support for the hypothesis that the sensory systems of signal targets should, in general, channel the evolution of signal structure. Furthermore, the discovery of previously undescribed signaling modalities such as infrared radiation should encourage us to overcome our own human-centered sensory biases and more fully examine the form and diversity of signals in the repertoires of many animal species.

  1. Identification of copper-based green pigments in Jaume Huguet's Gothic altarpieces by Fourier transform infrared microspectroscopy and synchrotron radiation X-ray diffraction.

    Science.gov (United States)

    Salvadó, N; Pradell, T; Pantos, E; Papiz, M Z; Molera, J; Seco, M; Vendrell-Saz, M

    2002-07-01

    The scientific investigation of ancient paintings gives a unique insight into ancient painting techniques and their evolution through time and geographic location. This study deals with the identification of the green pigments used by one of the most important Catalan masters in Gothic times, Jaume Huguet. Other pigments and materials have also been characterized by means of conventional techniques such as optical microscopy, scanning electron microscopy and Fourier transform infrared spectroscopy. Synchrotron radiation X-ray diffraction has been used to produce maps of phases at a spatial resolution of 100 microm across chromatic layers.

  2. Surface modification of Sylgard 184 polydimethylsiloxane by 254 nm excimer radiation and characterization by contact angle goniometry, infrared spectroscopy, atomic force and scanning electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Waddell, Emanuel A. [University of Alabama in Huntsville, Huntsville, AL (United States)], E-mail: ewaddell@chemistry.uah.edu; Shreeves, Stephen [University of Alabama in Huntsville, Huntsville, AL (United States); Carrell, Holly; Perry, Christopher [Oakwood College, Huntsville, AL (United States); Reid, Branden A. [Morgan State University, Baltimore, MD (United States); McKee, James [University of Alabama in Birmingham, Birmingham, AL (United States)

    2008-06-30

    The modification of polydimethylsiloxane (PDMS) by narrow band 254 nm excimer radiation under a nitrogen atmosphere was characterized by contact angle goniometry, attenuated total reflectance infrared spectroscopy, atomic force and scanning electron microscopy. UV irradiation results in the formation of the carboxylic acids that influences the wettability of the surface. Continued exposure results in the formation of an inorganic surface (SiO{sub x} (1 < x < 2)) which hinders the ability to continually increase the wettability. The continuity of this inorganic layer is disrupted by the formation of surface cracks. These results have implications in the fabrication and chemical modification of microfluidic or micro-electro-mechanical systems.

  3. Surface modification of Sylgard 184 polydimethylsiloxane by 254 nm excimer radiation and characterization by contact angle goniometry, infrared spectroscopy, atomic force and scanning electron microscopy

    Science.gov (United States)

    Waddell, Emanuel A.; Shreeves, Stephen; Carrell, Holly; Perry, Christopher; Reid, Branden A.; McKee, James

    2008-06-01

    The modification of polydimethylsiloxane (PDMS) by narrow band 254 nm excimer radiation under a nitrogen atmosphere was characterized by contact angle goniometry, attenuated total reflectance infrared spectroscopy, atomic force and scanning electron microscopy. UV irradiation results in the formation of the carboxylic acids that influences the wettability of the surface. Continued exposure results in the formation of an inorganic surface (SiO x (1 < x < 2)) which hinders the ability to continually increase the wettability. The continuity of this inorganic layer is disrupted by the formation of surface cracks. These results have implications in the fabrication and chemical modification of microfluidic or micro-electro-mechanical systems.

  4. Variable waveband infrared imager

    Science.gov (United States)

    Hunter, Scott R.

    2013-06-11

    A waveband imager includes an imaging pixel that utilizes photon tunneling with a thermally actuated bimorph structure to convert infrared radiation to visible radiation. Infrared radiation passes through a transparent substrate and is absorbed by a bimorph structure formed with a pixel plate. The absorption generates heat which deflects the bimorph structure and pixel plate towards the substrate and into an evanescent electric field generated by light propagating through the substrate. Penetration of the bimorph structure and pixel plate into the evanescent electric field allows a portion of the visible wavelengths propagating through the substrate to tunnel through the substrate, bimorph structure, and/or pixel plate as visible radiation that is proportional to the intensity of the incident infrared radiation. This converted visible radiation may be superimposed over visible wavelengths passed through the imaging pixel.

  5. Tattoos and human identification: investigation into the use of X-ray and infrared radiation in the visualization of tattoos.

    Science.gov (United States)

    Clarkson, Helen; Birch, Wendy

    2013-09-01

    Any person with a tattoo known to their family or friends could potentially be identified from the presence of such personal identifying markers. Problems in identification utilizing tattoos may arise when these markers are removed or defaced in some way. This paper uses infrared wavelengths at 760, 850, and 950 nm to improve the visualization of laser-removed or covered up tattoos and also to establish whether the ink pigments used can be observed on radiographs from any metal that may be present. The results obtained indicate that some older inks have a high enough metallic content to allow them to be viewed on a radiograph, while infrared light can demonstrate latent ink still present in the skin after laser removal and can also be utilized to distinguish an original tattoo through a secondary "cover-up" tattoo. Infrared photography and radiography have been shown to improve tattoo visualization in a forensic context. © 2013 American Academy of Forensic Sciences.

  6. Generation and characterization of ultra-short electron beams for single spike infrared FEL radiation at SPARC_LAB

    Science.gov (United States)

    Villa, F.; Anania, M. P.; Artioli, M.; Bacci, A.; Bellaveglia, M.; Bisesto, F. G.; Biagioni, A.; Carpanese, M.; Cardelli, F.; Castorina, G.; Chiadroni, E.; Cianchi, A.; Ciocci, F.; Croia, M.; Curcio, A.; Dattoli, G.; Gallo, A.; Di Giovenale, D.; Di Palma, E.; Di Pirro, G.; Ferrario, M.; Filippi, F.; Giannessi, L.; Giribono, A.; Marocchino, A.; Massimo, F.; Mostacci, A.; Petralia, A.; Petrarca, M.; Petrillo, V.; Piersanti, L.; Pioli, S.; Pompili, R.; Romeo, S.; Rossi, A. R.; Scifo, J.; Shpakov, V.; Vaccarezza, C.

    2017-09-01

    The technique for producing and measuring few tens of femtosecond electron beams, and the consequent generation of few tens femtoseconds single spike FEL radiation pulses at SPARC_LAB is presented. The undulator has been used in the double role of radiation source and diagnostic tool for the characterization of the electron beam. The connection between the electron bunch length and the radiation bandwidth is analyzed.

  7. Maps of Dust Infrared Emission for Use in Estimation of Reddening and Cosmic Microwave Background Radiation Foregrounds

    Science.gov (United States)

    Schlegel, David J.; Finkbeiner, Douglas P.; Davis, Marc

    1998-06-01

    We present a full-sky 100 μm map that is a reprocessed composite of the COBE/DIRBE and IRAS/ISSA maps, with the zodiacal foreground and confirmed point sources removed. Before using the ISSA maps, we remove the remaining artifacts from the IRAS scan pattern. Using the DIRBE 100 and 240 μm data, we have constructed a map of the dust temperature so that the 100 μm map may be converted to a map proportional to dust column density. The dust temperature varies from 17 to 21 K, which is modest but does modify the estimate of the dust column by a factor of 5. The result of these manipulations is a map with DIRBE quality calibration and IRAS resolution. A wealth of filamentary detail is apparent on many different scales at all Galactic latitudes. In high-latitude regions, the dust map correlates well with maps of H I emission, but deviations are coherent in the sky and are especially conspicuous in regions of saturation of H I emission toward denser clouds and of formation of H2 in molecular clouds. In contrast, high-velocity H I clouds are deficient in dust emission, as expected. To generate the full-sky dust maps, we must first remove zodiacal light contamination, as well as a possible cosmic infrared background (CIB). This is done via a regression analysis of the 100 μm DIRBE map against the Leiden-Dwingeloo map of H I emission, with corrections for the zodiacal light via a suitable expansion of the DIRBE 25 μm flux. This procedure removes virtually all traces of the zodiacal foreground. For the 100 μm map no significant CIB is detected. At longer wavelengths, where the zodiacal contamination is weaker, we detect the CIB at surprisingly high flux levels of 32 +/- 13 nW m-2 sr-1 at 140 μm and of 17 +/- 4 nW m-2 sr-1 at 240 μm (95% confidence). This integrated flux ~2 times that extrapolated from optical galaxies in the Hubble Deep Field. The primary use of these maps is likely to be as a new estimator of Galactic extinction. To calibrate our maps, we assume a

  8. Evaluation of an infrared camera and X-ray system using implanted fiducials in patients with lung tumors for gated radiation therapy

    International Nuclear Information System (INIS)

    Willoughby, Twyla R.; Forbes, Alan R.; Buchholz, Daniel; Langen, Katja M.; Wagner, Thomas H.; Zeidan, Omar A.; Kupelian, Patrick A.; Meeks, Sanford L.

    2006-01-01

    Purpose: To report on the initial clinical use of a commercially available system to deliver gated treatment using implanted fiducials, in-room kV X-rays, and an infrared camera tracking system. Methods and Materials: ExacTrac Adaptive Gating from BrainLab is a localization system using infrared cameras and X-rays. Gating signals are the patient's breathing pattern obtained from infrared reflectors on the patient. kV X-rays of an implanted fiducial are synchronized to the breathing pattern. After localization and shift of the patient to isocenter, the breathing pattern is used to gate Radiation. Feasibility tests included localization accuracy, radiation output constancy, and dose distributions with gating. Clinical experience is reported on treatment of patients with small lung lesions. Results: Localization accuracy of a moving target with gating was 1.7 mm. Dose constancy measurements showed insignificant change in output with gating. Improvements of dose distributions on moving targets improved with gating. Eleven patients with lung lesions were implanted with 20 mm x 0.7 mm gold coil (Visicoil). The implanted fiducial was used to localize and treat the patients with gating. Treatment planning and repeat computed tomographic scans showed that the change in center of gross target volume (GTV) to implanted marker averaged 2.47 mm due in part to asymmetric tumor shrinkage. Conclusion: ExacTrac Adaptive Gating has been used to treat lung lesions. Initial system evaluation verified its accuracy and usability. Implanted fiducials are visible in X-rays and did not migrate

  9. Predictive modeling of infrared radiative heating in tomato dry-peeling process: Part II. Model validation and sensitivity analysis

    Science.gov (United States)

    A predictive mathematical model was developed to simulate heat transfer in a tomato undergoing double sided infrared (IR) heating in a dry-peeling process. The aims of this study were to validate the developed model using experimental data and to investigate different engineering parameters that mos...

  10. Iterative maximum a posteriori (IMAP-DOAS for retrieval of strongly absorbing trace gases: Model studies for CH4 and CO2 retrieval from near infrared spectra of SCIAMACHY onboard ENVISAT

    Directory of Open Access Journals (Sweden)

    C. Frankenberg

    2005-01-01

    Full Text Available In the past, differential optical absorption spectroscopy (DOAS has mostly been employed for atmospheric trace gas retrieval in the UV/Vis spectral region. New spectrometers such as SCIAMACHY onboard ENVISAT also provide near infrared channels and thus allow for the detection of greenhouse gases like CH4, CO2, or N2O. However, modifications of the classical DOAS algorithm are necessary to account for the idiosyncrasies of this spectral region, i.e. the temperature and pressure dependence of the high resolution absorption lines. Furthermore, understanding the sensitivity of the measurement of these high resolution, strong absorption lines by means of a non-ideal device, i.e. having finite spectral resolution, is of special importance. This applies not only in the NIR, but can also prove to be an issue for the UV/Vis spectral region. This paper presents a modified iterative maximum a posteriori-DOAS (IMAP-DOAS algorithm based on optimal estimation theory introduced to the remote sensing community by rodgers76. This method directly iterates the vertical column densities of the absorbers of interest until the modeled total optical density fits the measurement. Although the discussion in this paper lays emphasis on satellite retrieval, the basic principles of the algorithm also hold for arbitrary measurement geometries. This new approach is applied to modeled spectra based on a comprehensive set of atmospheric temperature and pressure profiles. This analysis reveals that the sensitivity of measurement strongly depends on the prevailing pressure-height. The IMAP-DOAS algorithm properly accounts for the sensitivity of measurement on pressure due to pressure broadening of the absorption lines. Thus, biases in the retrieved vertical columns that would arise in classical algorithms, are obviated. Here, we analyse and quantify these systematic biases as well as errors due to variations in the temperature and pressure profiles, which is indispensable for

  11. Aerosol radiative effects in the ultraviolet, visible, and near-infrared spectral ranges using long-term aerosol data series over the Iberian Peninsula

    Science.gov (United States)

    Mateos, D.; Antón, M.; Toledano, C.; Cachorro, V. E.; Alados-Arboledas, L.; Sorribas, M.; Costa, M. J.; Baldasano, J. M.

    2014-04-01

    A better understanding of the aerosol radiative properties is a crucial challenge for climate change studies. This study aims to provide a complete characterization of aerosol radiative effects in different spectral ranges within the shortwave (SW) solar spectrum. For this purpose, long-term datasets of aerosol properties from six AERONET stations located in the Iberian Peninsula (Southwestern Europe) are analyzed in term of climatology characterization and trends. Aerosol information is used as input to the libRadtran model in order to determine the aerosol radiative effect at the surface in the ultraviolet (AREUV), visible (AREVIS), near-infrared (ARENIR), and the entire SW range (ARESW) under cloud-free conditions. Over the whole Iberian Peninsula, aerosol radiative effects in the different spectral ranges are: -1.1 solar radiation at the surface is seen. Monthly means of ARE show a seasonal pattern with larger values in spring and summer. The aerosol forcing efficiency (AFE), ARE per unit of aerosol optical depth, is also evaluated in the four spectral ranges. AFE exhibits a dependence on single scattering albedo and a weaker one on Ångström exponent. AFE is larger (in absolute value) for small and absorbing particles. The contributions of the UV, VIS, and NIR ranges to the SW efficiency vary with the aerosol types. Aerosol size determines the fractions of AFEVIS/AFESW and AFENIR/AFESW. VIS range is the dominant region for all types, although non-absorbing large particles cause a more equal contribution of VIS and NIR intervals. The AFEUV / AFESW ratio shows a higher contribution for absorbing fine particles.

  12. The influence of insulation of walls of industrial objects on thermal regime at the heating system of gas infrared radiators

    OpenAIRE

    Nagornova Tatiana; Emelenchuk Vladimir

    2017-01-01

    The results of a numerical study of the process of heat transfer from the gas infrared emitters in the heated accommodation are represented. Simulation was conducted taking into account the heat withdrawal in the enclosing constructions and of heat exchange with the environment. The estimation of the average values of temperatures of air indoors in the dependence on the different intensity of heat withdrawal into the vertical walls is carried out (when the layer of insulation is present, and ...

  13. Origin of the spectral deformation in the near infrared radiation from Tore-Supra carbon components; Origine de la deformation spectrale de la luminance proche infrarouge des composants en carbone de Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Delchambre, E

    2004-03-01

    This work concerns the understanding of a physical phenomenon which is important for the future course of magnetic confinement fusion research: namely the anomalous deformation in the near infrared of radiation from tokamak plasma facing components under plasma particle impact. The goal of this work was to reproduce this phenomenon in laboratory experiments, characterize it and explain it, so that the measurements of the temperature of plasma facing components can be made with confidence. Laboratory experiments have been performed using an ECR ions source and a helicon plasma source. The spectral luminance deformation has been observed on graphite surface under electrons and ions bombardment and the amplitude of this phenomenon was found to depend on the type of material used and the power density of the incident particles. A systematic consideration and evaluation of alternative explanations for the observed spectral deformation has been made. A number of plausible interpretations has been considered and discarded as e.g. Bremsstrahlung radiation, or assigned a low probability as the luminescence effect. The possible partial transparency of the material has also been considered at some length, but finally discarded because the low thermal conductivity of the graphite materials under consideration does not permit a strong enough temperature gradient to cause the observed deformation. The possible explanation is reduced to the non uniform surface temperature due to the presence of hot spots during particle bombardment. This hypothesis implies that the measured luminance is the contribution of several temperatures. The measured spectral luminance deformation, basing on hot spots hypothesis, is simulated. This hypothesis allows to asses the surface temperature, the hot spots temperature and the hot spots coverage on the surface. These results are validated using a thermal model of dust in radiate equilibrium. This model allows us to deduce an average size of the dust

  14. Radiative parameters for multi-channel visible and near-infrared emission transitions of Sm3+ in heavy-metal-silicate glasses

    Science.gov (United States)

    Yang, Jie; Zhai, Bin; Zhao, Xin; Wang, Zhiqiang; Lin, Hai

    2013-05-01

    Multi-channel visible and near-infrared (NIR) emission transitions originating from 4G5/2 emitting state of Sm3+ in cadmium-aluminum-silicate (CAS) glasses with maximum-phonon-energy of ˜980 cm-1 have been investigated. Based on the measured absorption spectrum, the Judd-Ofelt parameters Ωt (t=2, 4, 6) are derived to be 2.87×10-20, 3.34×10-20 and 1.86×10-20 cm2, respectively. From the evaluated Judd-Ofelt parameters, the radiative parameters such as spontaneous emission probabilities (Arad), branching ratios (β), and radiative lifetime (τrad) are obtained from the 4G5/2 excited level to different lower energy levels. The efficient visible and NIR transition emissions have been observed in the Sm3+ doped CAS glasses, and the maximum stimulated emission cross-sections (σe-max) corresponding to emission peaks are calculated and demonstrated to lay in the same order of magnitude. The quantum efficiency of 4G5/2 level of Sm3+ has been derived to be 60%. Investigations on multi-channel radiative transition emissions originated from 4G5/2 level of Sm3+ in CAS glasses expose its potential applications in tunable laser, medical light source and NIR optoelectronic devices.

  15. A multi-channel THz and infrared spectrometer for femtosecond electron bunch diagnostics by single-shot spectroscopy of coherent radiation

    International Nuclear Information System (INIS)

    Wesch, Stephan; Schmidt, Bernhard; Behrens, Christopher; Delsim-Hashemi, Hossein; Schmueser, Peter

    2011-08-01

    The high peak current required in free-electron lasers (FELs) is realized by longitudinal compression of the electron bunches to sub-picosecond length. In this paper, a frequency-domain diagnostic method is described that is capable of resolving structures in the femtosecond regime. A novel in-vacuum spectrometer has been developed for spectroscopy of coherent radiation in the THz and infrared range. The spectrometer is equipped with five consecutive dispersion gratings and 120 parallel readout channels; it can be operated either in short wavelength mode (5-44 μm) or in long wavelength mode (45-430 μm). Fast parallel readout permits the spectroscopy of coherent radiation from single electron bunches. Test measurements at the soft X-ray free-electron laser FLASH, using coherent transition radiation, demonstrate excellent performance of the spectrometer. The high sensitivity down to a few micrometers allows study of short bunch features caused for example by microbunching e ects in magnetic chicanes. The device is planned for use as an online bunch profile monitor during regular FEL operation. (orig.)

  16. A multi-channel THz and infrared spectrometer for femtosecond electron bunch diagnostics by single-shot spectroscopy of coherent radiation

    Energy Technology Data Exchange (ETDEWEB)

    Wesch, Stephan; Schmidt, Bernhard; Behrens, Christopher; Delsim-Hashemi, Hossein; Schmueser, Peter

    2011-08-15

    The high peak current required in free-electron lasers (FELs) is realized by longitudinal compression of the electron bunches to sub-picosecond length. In this paper, a frequency-domain diagnostic method is described that is capable of resolving structures in the femtosecond regime. A novel in-vacuum spectrometer has been developed for spectroscopy of coherent radiation in the THz and infrared range. The spectrometer is equipped with five consecutive dispersion gratings and 120 parallel readout channels; it can be operated either in short wavelength mode (5-44 {mu}m) or in long wavelength mode (45-430 {mu}m). Fast parallel readout permits the spectroscopy of coherent radiation from single electron bunches. Test measurements at the soft X-ray free-electron laser FLASH, using coherent transition radiation, demonstrate excellent performance of the spectrometer. The high sensitivity down to a few micrometers allows study of short bunch features caused for example by microbunching e ects in magnetic chicanes. The device is planned for use as an online bunch profile monitor during regular FEL operation. (orig.)

  17. Theoretical and experimental drying of a cylindrical sample by applying hot air and infrared radiation in an inert medium fluidized bed

    Directory of Open Access Journals (Sweden)

    B. Honarvar

    2012-06-01

    Full Text Available Drying of a cylindrical sample in a fluidized bed dryer containing inert particles was studied. For this purpose, a pilot-scaled fluidized bed dryer was constructed in which two different heat sources, hot air and infrared radiation were applied, and pieces of carrot were chosen as test samples. The heat transfer coefficient for cylindrical objects in a fluidized bed was also measured. The heat absorption coefficient for carrot was studied. The absorption coefficient can be computed by dividing the absorbed heat by the carrot to the heat absorbed for the water and black ink. In this regard, absorbed heat values by the carrot, water and black ink were used A mathematical model was proposed based on the mass and heat transfer phenomena within the drying sample. The results obtained by the proposed model were in favorable agreement with the experimental data.

  18. Pollution Encrustation Removal by Means of Combined Ultraviolet and Infrared Laser Radiation: The Application of this Innovative Methodology on the Surface of the Parthenon West Frieze

    Science.gov (United States)

    Pouli, P.; Frantzikinaki, K.; Papakonstantinou, E.; Zafiropulos, V.; Fotakis, C.

    This study refers to the innovative laser cleaning methodology developed at FORTH IESL on the combination of ultraviolet and infrared laser radiation emitted from a Q-switched Nd:YAG laser for the successful removal of pollution encrustation from marble substrates. The above-mentioned methodology is presented as regards its successful application on the fragile and demanding surface of the Parthenon West Frieze in collaboration with the Committee for the Preservation of the Acropolis Monuments. The aim of this intervention was to remove encrustation, accumulated on the stone due to the atmospheric pollution, without any discoloration or structural alteration to the original surface. The preliminary experiments on all the possible substrates and encrustations present on the surface of the Acropolis monuments and the laser cleaning parameters are presented in detail.

  19. Revisiting the Cause of the 1989-2009 Arctic Surface Warming Using the Surface Energy Budget: Downward Infrared Radiation Dominates the Surface Fluxes

    Science.gov (United States)

    Lee, Sukyoung; Gong, Tingting; Feldstein, Steven B.; Screen, James A.; Simmonds, Ian

    2017-10-01

    The Arctic has been warming faster than elsewhere, especially during the cold season. According to the leading theory, ice-albedo feedback warms the Arctic Ocean during the summer, and the heat gained by the ocean is released during the winter, causing the cold-season warming. Screen and Simmonds (2010; SS10) concluded that the theory is correct by comparing trend patterns in surface air temperature (SAT), surface turbulence heat flux (HF), and net surface infrared radiation (IR). However, in this comparison, downward IR is more appropriate to use. By analyzing the same data used in SS10 using the surface energy budget, it is shown here that over most of the Arctic the skin temperature trend, which closely resembles the SAT trend, is largely accounted for by the downward IR, not the HF, trend.

  20. Upregulated epidermal growth factor receptor expression following near-infrared irradiation simulating solar radiation in a three-dimensional reconstructed human corneal epithelial tissue culture model

    Directory of Open Access Journals (Sweden)

    Tanaka Y

    2016-08-01

    Full Text Available Yohei Tanaka,1,2 Jun Nakayama2 1Department of Plastic Surgery, Clinica Tanaka Plastic, Reconstructive Surgery and Anti-aging Center, 2Department of Molecular Pathology, Shinshu University Graduate School of Medicine, Matsumoto, Nagano, Japan Background and objective: Humans are increasingly exposed to near-infrared (NIR radiation from both natural (eg, solar and artificial (eg, electrical appliances sources. Although the biological effects of sun and ultraviolet (UV exposure have been extensively investigated, the biological effect of NIR radiation is still unclear. We previously reported that NIR as well as UV induces photoaging and standard UV-blocking materials, such as sunglasses, do not sufficiently block NIR. The objective of this study was to investigate changes in gene expression in three-dimensional reconstructed corneal epithelial tissue culture exposed to broad-spectrum NIR irradiation to simulate solar NIR radiation that reaches human tissues.Materials and methods: DNA microarray and quantitative real-time polymerase chain reaction analysis were used to assess gene expression levels in a three-dimensional reconstructed corneal epithelial model composed of normal human corneal epithelial cells exposed to water-filtered broad-spectrum NIR irradiation with a contact cooling (20°C. The water-filter allowed 1,000–1,800 nm wavelengths and excluded 1,400–1,500 nm wavelengths.Results: A DNA microarray with >62,000 different probes showed 25 and 150 genes that were up- or downregulated by at least fourfold and twofold, respectively, after NIR irradiation. In particular, epidermal growth factor receptor (EGFR was upregulated by 19.4-fold relative to control cells. Quantitative real-time polymerase chain reaction analysis revealed that two variants of EGFR in human corneal epithelial tissue were also significantly upregulated after five rounds of 10 J/cm2 irradiation (P<0.05.Conclusion: We found that NIR irradiation induced the

  1. Identification of the absorbed infrared spectra of 1700 cm-1 in the radiation solid phase polymerization of aisotactic polyacrylonitrile

    International Nuclear Information System (INIS)

    Minagawa, M.; Umehara, R.; Matsuyama, T.; Sato, N.

    2004-01-01

    The monomer (AN) was mixed with gamma ray irradiation urea, and slight precipitation was obtained when methanol was poured out and collected after several months at low temperature. It was shown that this precipitation is the polymer, which the monomer combined with urea. Moreover, it was shown clearly from the measurement results of an infrared absorption spectrum and a NMR spectrum that it was the aisotactic polyacrylonitrile (PAN). The spectrum of 1700cm -1 seen with IR absorption spectrum of this polymer is from a carbonyl band (C=O), and it became clear that it is the spectrum of the urea origin. (H. Katsuta)

  2. The influence of insulation of walls of industrial objects on thermal regime at the heating system of gas infrared radiators

    Directory of Open Access Journals (Sweden)

    Nagornova Tatiana

    2017-01-01

    Full Text Available The results of a numerical study of the process of heat transfer from the gas infrared emitters in the heated accommodation are represented. Simulation was conducted taking into account the heat withdrawal in the enclosing constructions and of heat exchange with the environment. The estimation of the average values of temperatures of air indoors in the dependence on the different intensity of heat withdrawal into the vertical walls is carried out (when the layer of insulation is present, and without it.

  3. Upregulated epidermal growth factor receptor expression following near-infrared irradiation simulating solar radiation in a three-dimensional reconstructed human corneal epithelial tissue culture model.

    Science.gov (United States)

    Tanaka, Yohei; Nakayama, Jun

    2016-01-01

    Humans are increasingly exposed to near-infrared (NIR) radiation from both natural (eg, solar) and artificial (eg, electrical appliances) sources. Although the biological effects of sun and ultraviolet (UV) exposure have been extensively investigated, the biological effect of NIR radiation is still unclear. We previously reported that NIR as well as UV induces photoaging and standard UV-blocking materials, such as sunglasses, do not sufficiently block NIR. The objective of this study was to investigate changes in gene expression in three-dimensional reconstructed corneal epithelial tissue culture exposed to broad-spectrum NIR irradiation to simulate solar NIR radiation that reaches human tissues. DNA microarray and quantitative real-time polymerase chain reaction analysis were used to assess gene expression levels in a three-dimensional reconstructed corneal epithelial model composed of normal human corneal epithelial cells exposed to water-filtered broad-spectrum NIR irradiation with a contact cooling (20°C). The water-filter allowed 1,000-1,800 nm wavelengths and excluded 1,400-1,500 nm wavelengths. A DNA microarray with >62,000 different probes showed 25 and 150 genes that were up- or downregulated by at least fourfold and twofold, respectively, after NIR irradiation. In particular, epidermal growth factor receptor (EGFR) was upregulated by 19.4-fold relative to control cells. Quantitative real-time polymerase chain reaction analysis revealed that two variants of EGFR in human corneal epithelial tissue were also significantly upregulated after five rounds of 10 J/cm(2) irradiation (Psolar energy reaching the Earth is in the NIR region, which cannot be adequately blocked by eyewear and thus can induce eye damage with intensive or long-term exposure, protection from both UV and NIR radiation may prevent changes in gene expression and in turn eye damage.

  4. Long-wave infrared radiation reflected by compression stockings in the treatment of cellulite: a clinical double-blind, randomized and controlled study.

    Science.gov (United States)

    Bagatin, E; Miot, H A; Soares, J L M; Sanudo, A; Afonso, J P J M; de Barros Junior, N; Talarico, S

    2013-10-01

    Cellulite refers to changes in skin relief on the thighs and buttocks of women, with a prevalence of 80-90%, causing dissatisfaction and search for treatment. Etiopathogenesis is multifactorial, as follows: herniation of the hypodermis towards the dermis, facilitated by perpendicular fibrous septa, changes in the dermal extracellular matrix, decreased adiponectin, genetic polymorphism, microcirculation alterations and inflammatory process. There are numerous therapeutic approaches, with little evidence of effectiveness. The long-wave infrared (LWIR) radiation interacts with water, improves microcirculation and stimulates metabolic processes. To date, the use of tissues with potential reflection of LWIR radiation has not been systematically investigated as adjuvant treatment for cellulite. To investigate the efficacy and safety of the treatment of cellulite through the use of compression stockings made with thread reflecting LWIR radiation. Clinical study of therapeutic intervention, controlled and double-blind, including 30 women, aging from 25 to 40 years, with cellulite of grades II and III on the thighs and buttocks who used compression stockings, "pantyhose" model, made with reflector thread of LWIR radiation, on only one randomized side. Women under other treatments for cellulite and with venous and/or blood insufficiencies were excluded. Evaluation of efficacy by clinical parameters, photographs, Dermatology Life Quality Index (DLQI), cutometry and high frequency ultrasonography and security by observation of adverse events and venous EcoDoppler recordings. DLQI scores showed significant reduction; the two-dimensional high-frequency ultrasonography showed an insignificant increase in dermal echogenicity as well as other efficacy parameters demonstrated no or slight improvement, with no differences between the sides exposed or not to LWIR; and there were no severe adverse events. Compression stockings, with or without thread reflector of LWIR, showed slight

  5. Novel High Temperature and Radiation Resistant Infrared Glasses and Optical Fibers for Sensing in Advanced Small Modular Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ballato, John [Clemson Univ., SC (United States)

    2018-01-22

    One binary and three series of ternary non-oxide pure sulfide glasses compositions were investigated with the goal of synthesizing new glasses that exhibit high glass transition (Tg) and crystallization (Tc) temperatures, infrared transparency, and reliable glass formability. The binary glass series consisted of Ges2 and La2S3 and the three glass series in the x(nBaS + mLa2S3) + (1-2x)GeS2 ternary system have BaS:La2S3 modifier ratios of 1:1, 1:2, and 2:1 with . With these glasses, new insights were realized as to how ionic glasses form and how glass modifiers affect both structure and glass formability. All synthesized compositions were characterized by Infrared (IR) and Raman spectroscopies and differential thermal analysis (DTA) to better understand the fundamental structure, optical, and thermal characteristics of the glasses. After a range of these glasses were synthesized, optimal compositions were formed into glass disks and subjected to gamma irradiation. Glass disks were characterized both before and after irradiation by microscope imaging, measuring the refractive index, density, and UV-VIS-IR transmission spectra. The final total dose the samples were subjected to was ~2.5 MGy. Ternary samples showed a less than 0.4% change in density and refractive index and minimal change in transmission window. The glasses also resisted cracking as seen in microscope images. Overall, many glass compositions were developed that possess operating temperatures above 500 °C, where conventional chalcogenide glasses such as As2S3 and have Tgs from ~200-300 °C, and these glasses have a greater than Tc – Tg values larger than 100 °C and this shows that these glasses have good thermal stability of Tg such that they can be fabricated into optical fibers and as such can be considered candidates for high temperature infrared fiber optics. Initial fiber fabrication efforts showed that selected glasses could be drawn but larger

  6. LIME - a flexible, non-LTE line excitation and radiation transfer method for millimeter and far-infrared wavelengths

    DEFF Research Database (Denmark)

    Brinch, Christian; Hogerheijde, Michiel

    2010-01-01

    We present a new code for solving the molecular and atomic excitation and radiation transfer problem in a molecular gas and predicting emergent spectra. This code works in arbitrary three dimensional geometry using unstructured Delaunay latices for the transport of photons. Various physical models...... can be used as input, ranging from analytical descriptions over tabulated models to SPH simulations. To generate the Delaunay grid we sample the input model randomly, but weigh the sample probability with the molecular density and other parameters, and thereby we obtain an average grid point...... separation that scales with the local opacity. Our code does photon very efficiently so that the slow convergence of opaque models becomes traceable. When convergence between the level populations, the radiation field, and the point separation has been obtained, the grid is ray-traced to produced images...

  7. Far-infrared transition and diffraction radiation. Pt. 2. The THz beamline at the VUV-FEL linac

    International Nuclear Information System (INIS)

    Casalbuoni, S.; Schmidt, B.; Schmueser, P.; Steffen, B.; Hamburg Univ.

    2006-01-01

    In order to facilitate longitudinal bunch diagnostics with high-resolution interferometric or spectroscopic devices outside the VUV-FEL tunnel we have designed a Tera-Hertz beamline at the 140 m position of the VUV-FEL linac. The vacuum chamber housing the transition and diffraction radiation screens is located between the last acceleration module and the collimator section in front of the undulator. In Part I of this report we have presented a general scheme for computing the generation, diffraction and optical propagation of transition and diffraction radiation. In the present Part II we describe the design, technical layout and optical performance of the THz beamline at the VUV-FEL and show first measurements. (orig.)

  8. Free-free absorption of infrared radiation in collisions of electrons with neutral rare-gas atoms

    Science.gov (United States)

    Stallcop, J. R.

    1974-01-01

    A relationship between the inverse bremsstrahlung absorption cross section and the electron neutral momentum transfer cross section has been utilized to determine the infrared free-free continuum absorption coefficient for the negative ions of helium, neon, argon, krypton, and xenon. The values of the momentum transfer cross section for this calculation have been obtained from experimental measurements. Analytical expressions for the absorption coefficient have also been developed. From the results of this calculation, it is possible to determine the absorption coefficient per unit electron density per neutral atom for temperatures in the range from 2500 to 25,000 K. The results are compared with those from tabulations of previous calculations and those computed from theoretical values of the phase shifts for the elastic scattering of electrons by neutral atoms.

  9. Simulations of cloudy hyperspectral infrared radiances using the HT-FRTC, a fast PC-based multipurpose radiative transfer code

    Science.gov (United States)

    Havemann, S.; Aumann, H. H.; Desouza-Machado, S. G.

    2017-12-01

    The HT-FRTC uses principal components which cover the spectrum at a very high spectral resolution allowing very fast line-by-line-like, hyperspectral and broadband simulations for satellite-based, airborne and ground-based sensors. Using data from IASI and from the Airborne Research Interferometer Evaluation System (ARIES) on board the FAAM BAE 146 aircraft, variational retrievals in principal component space with HT-FRTC as forward model have demonstrated that valuable information on temperature and humidity profiles and on the cirrus cloud properties can be obtained simultaneously. The NASA/JPL/UMBC cloudy RTM inter-comparison project has been working on a global dataset consisting of 7377 AIRS spectra. Initial simulations with HT-FRTC for this dataset have been promising. A next step taken here is to investigate how sensitive the results are with respect to different assumptions in the cloud modelling. One aspect of this is to study how assumptions about the microphysical and related optical properties of liquid/ice clouds impact the statistics of the agreement between model and observations. The other aspect is about the cloud overlap scheme. Different schemes have been tested (maximum, random, maximum random). As the computational cost increases linearly with the number of cloud columns, it will be investigated if there is an optimal number of columns beyond which there is little additional benefit to be gained. During daytime the high wave number channels of AIRS are affected by solar radiation. With full scattering calculations using a monochromatic version of the Edwards-Slingo radiation code the HT-FRTC can model solar radiation reasonably well, but full scattering calculations are relatively expensive. Pure Chou scaling on the other hand can not properly describe scattering of solar radiation by clouds and requires additional refinements.

  10. Near-infrared radiation induced conformational change and hydrogen atom tunneling of 2-chloropropionic acid in low-temperature Ar matrix.

    Science.gov (United States)

    Bazsó, Gábor; Góbi, Sándor; Tarczay, György

    2012-05-24

    Former assignments of the matrix-isolation infrared (MI-IR) spectrum of 2-chloropropionic acid are revised with the help of near-infrared (NIR) laser irradiation induced change in conformer ratios. This method allows not only the unambiguous assignment of each band in the MI-IR spectrum to the two trans (Z) and the cis (E) conformers but also the assignment of the spectral bands to different matrix sites. The tunneling decay of the higher-energy cis conformer prepared from both trans conformers in different sites is also investigated. It is shown that the tunneling decay time is very sensitive to the matrix site, especially if the in situ prepared high-energy conformer has a strained geometry in the matrix cage. The analysis shows that the kinetics of some cis → trans back conversion processes cannot be fitted by a single exponential decay. The possible reasons of this observation are examined and discussed. The present and former results clearly show that, in addition to tunneling processes, the decay rates strongly depend on solid-state effects. Therefore, simple theoretical predictions of decay rates, which do not take into account the solid-state effects, can only be compared to experimental observations only if experimentally proven that these effects do not significantly affect the experimentally measured tunneling rates.

  11. LIME - a flexible, non-LTE line excitation and radiation transfer method for millimeter and far-infrared wavelengths

    DEFF Research Database (Denmark)

    Brinch, Christian; Hogerheijde, Michiel

    2010-01-01

    We present a new code for solving the molecular and atomic excitation and radiation transfer problem in a molecular gas and predicting emergent spectra. This code works in arbitrary three dimensional geometry using unstructured Delaunay latices for the transport of photons. Various physical models...... that can readily be compared to observations. Because of the high dynamic range in scales that can be resolved using this type of grid, our code is particularly well suited for modeling of ALMA data. Our code can furthermore deal with overlapping lines of multiple molecular and atomic species....

  12. Nanoscale Devices for Rectification of High Frequency Radiation from the Infrared through the Visible: A New Approach

    Directory of Open Access Journals (Sweden)

    N. M. Miskovsky

    2012-01-01

    Full Text Available We present a new and viable method for optical rectification. This approach has been demonstrated both theoretically and experimentally and is the basis fot the development of devices to rectify radiation through the visible. This technique for rectification is based not on conventional material or temperature asymmetry as used in MIM (metal/insulator/metal or Schottky diodes, but on a purely sharp geometric property of the antenna. This sharp “tip” or edge with a collector anode constitutes a tunnel junction. In these devices the rectenna (consisting of the antenna and the tunnel junction acts as the absorber of the incident radiation and the rectifier. Using current nanofabrication techniques and the selective atomic layer deposition (ALD process, junctions of 1 nm can be fabricated, which allow for rectification of frequencies up to the blue portion of the spectrum. To assess the viability of our approach, we review the development of nanoantenna structures and tunnel junctions capable of operating in the visible region. In addition, we review the detailed process of rectification and present methodologies for analysis of diode data. Finally, we present operational designs for an optical rectenna and its fabrication and discuss outstanding problems and future work.

  13. A new, low temperature long-pass cell for mid-infrared to terahertz spectroscopy and synchrotron radiation use

    Energy Technology Data Exchange (ETDEWEB)

    Kwabia Tchana, Fridolin; Willaert, Fabrice; Landsheere, Xavier; Flaud, Jean-Marie [LISA, Laboratoire Interuniversitaire des Systèmes Atmosphériques, UMR CNRS 7583, Université Paris-Est Créteil (UPEC) et Université Paris-Diderot (UPD), 61 Avenue du Général de Gaulle, 94010 Créteil Cedex (France); Lago, Leatitia; Chapuis, Mylène; Herbeaux, Christian; Roy, Pascale; Manceron, Laurent [High Vacuum Group and Beamline AILES, Synchrotron SOLEIL, L’Orme des Merisiers, F-91192 Gif-sur-Yvette (France)

    2013-09-15

    A new cell has been designed for accurate spectroscopic measurements in the 80–400 K temperature range with variable path lengths from 3 to more than 141 m. The spectral coverage at these temperatures ranges from the visible to less than 10 cm{sup −1}, thanks to the use of diamond windows. The design of the cryostat and vacuum setups allows vibration-free operation. The equipment provides temperature homogeneity and pressure control to better than 2% over the 100–400 K and the 0.1–1000 mbar ranges. Remote-controlled opto-mechanical systems enable in situ adjustments as well as changes of the optical path length within half an hour, in order to optimize measurement time in an open user facility. It allows then to meet the specific requirements of high resolution measurements on the Far-Infrared AILES beamline at SOLEIL as well at the LISA facility, in Créteil, in the mid-IR. This new instrument opens up the way for many experiments in the field of high-resolution gas-phase IR spectroscopy, in particular, in quantitative spectroscopy for atmospheric applications: measurements of absorption line parameters (absolute intensities, cross sections, and pressure-induced widths) using Fourier transform spectroscopy. The design and performance of the equipment are briefly presented and illustrated on spectroscopic examples.

  14. Properties of the generation of radiation in the near infrared part of the spectrum with a sapphire crystal laser having radiation-induced color centers

    International Nuclear Information System (INIS)

    Voitovich, A.P.; Grinkevich, V.E.; Kononov, V.A.; Kromskii, G.I.

    1986-01-01

    This paper investigates the spectral stability of the color centers in sapphire and the energy of lasers in which the active elements were colored with various techniques. Color centers were produced by neutron irradiation. The absorption spectra of the color centers are shown. The transformation of the spectra shows that the mutual conversions of color centers takes place during the thermal annealing of the sapphire; most of the color centers formed have luminescence. Generation or radiation with a tunable frequency was obtained in the case of transverse or quasi-longitudinal excitation by a ruby laser. The results show that ways for increasing the stability of the energy generated by a sapphire laser with color centers can be found

  15. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  16. Behaviour of glutathione in the cornea epithelium of cattle and rabbits under the influence of infrared radiation

    International Nuclear Information System (INIS)

    Scharsich, G.

    1978-01-01

    After creating a keratitis photoelectrica by means of a mercury/quartz analysis lamp, the concentration of GSH (glutathion, reduced) and GSSG (glutathion, oxidised) in the cornea epithelium of cattle and of rabbits at different times after irradiation was determined. The question of whether ultraviolet radiation considerably influences the GSH/GSSG quotient before the keratitis photoelectrica is fully formed morphologically, could be answered as follows: There is no considerable change in the GSH/GSSG quotient during the first 7-10 hours after the irradiation. Then, when there is, also morphologically, a keratitis photoelectrica, the GSH/GSSG quotient is doubled. The linkage of the GSH/GSSG system and hexosephosphatshunt via the NADP/NADPH system leads us to the conclusion that irradiation does not cause any direct changes in the GSH/GSSG system. Only when the cornea epithelium visably disintegrates an increased reduction of the glutathion occurs, like in several other damaging influences. Thus the found increase of the GSH/GSSG quotient 7-10 hours after ultraviolet irradiation might be unspecific. (orig./AJ) [de

  17. Preliminary studies of the effects of psychological stress on circulating lymphocytes analyzed by synchrotron radiation based-Fourier transform infrared microspectroscopy

    Science.gov (United States)

    Vargas-Caraveo, Alejandra; Castillo-Michel, Hiram; Mejia-Carmona, Gloria Erika; Pérez-Ishiwara, David Guillermo; Cotte, Marine; Martínez-Martínez, Alejandro

    2014-07-01

    Psychological stress is a condition that not only generates behavioral disorders but also disrupts homeostasis and immune activity that can exacerbate or lead to inflammatory diseases. The aim of this work was to study biochemical changes in circulating immune cells from rats under psychological stress by using vibrational spectroscopy. A stress model was used, where exposure to a stressor was repeated for 5 days. Subsequently, circulating lymphocytes were examined for their biomolecular vibrational fingerprints with synchrotron radiation based-Fourier transform infrared microspectroscopy. The results showed an increased absorption at the ester lipid region (1720-1755 cm-1) in lymphocytes from stressed rats, suggesting lipid peroxidation. Statistical significant changes in wavenumber peak position and absorbance in the nucleic acid region were also observed (915-950 cm-1 Z-DNA, 1090-1150 cm-1 symmetric stretching of Psbnd Osbnd C, 1200-1260 cm-1 asymmetric PO2 and 1570-1510 cm-1 methylated nucleotides) which suggest a reduction of transcriptional activity in lymphocytes from stressed rat. These results unravel part of the mechanisms by which psychological stress may affect the immune system leading to systemic consequences.

  18. Infrared Devices And Techniques (Revision)

    OpenAIRE

    Rogalski A.; Chrzanowski K.

    2014-01-01

    The main objective of this paper is to produce an applications-oriented review covering infrared techniques and devices. At the beginning infrared systems fundamentals are presented with emphasis on thermal emission, scene radiation and contrast, cooling techniques, and optics. Special attention is focused on night vision and thermal imaging concepts. Next section concentrates shortly on selected infrared systems and is arranged in order to increase complexity; from image intensifier systems,...

  19. Scalable-manufactured randomized glass-polymer hybrid metamaterial for daytime radiative cooling

    Science.gov (United States)

    Zhai, Yao; Ma, Yaoguang; David, Sabrina N.; Zhao, Dongliang; Lou, Runnan; Tan, Gang; Yang, Ronggui; Yin, Xiaobo

    2017-03-01

    Passive radiative cooling draws heat from surfaces and radiates it into space as infrared radiation to which the atmosphere is transparent. However, the energy density mismatch between solar irradiance and the low infrared radiation flux from a near-ambient-temperature surface requires materials that strongly emit thermal energy and barely absorb sunlight. We embedded resonant polar dielectric microspheres randomly in a polymeric matrix, resulting in a metamaterial that is fully transparent to the solar spectrum while having an infrared emissivity greater than 0.93 across the atmospheric window. When backed with a silver coating, the metamaterial shows a noontime radiative cooling power of 93 watts per square meter under direct sunshine. More critically, we demonstrated high-throughput, economical roll-to-roll manufacturing of the metamaterial, which is vital for promoting radiative cooling as a viable energy technology.

  20. Atoms and clusters in strong laser fields

    NARCIS (Netherlands)

    Marchenko, T.

    2008-01-01

    This thesis describes experimental and theoretical studies on the interaction of strong infrared laser fields with atoms and atomic clusters. Part I provides an overview of the main strong-field phenomena in atoms, molecules and clusters and describes the state-of-the-art in strong-field science.

  1. Combining Lactic Acid Spray with Near-Infrared Radiation Heating To Inactivate Salmonella enterica Serovar Enteritidis on Almond and Pine Nut Kernels.

    Science.gov (United States)

    Ha, Jae-Won; Kang, Dong-Hyun

    2015-07-01

    The aim of this study was to investigate the efficacy of near-infrared radiation (NIR) heating combined with lactic acid (LA) sprays for inactivating Salmonella enterica serovar Enteritidis on almond and pine nut kernels and to elucidate the mechanisms of the lethal effect of the NIR-LA combined treatment. Also, the effect of the combination treatment on product quality was determined. Separately prepared S. Enteritidis phage type (PT) 30 and non-PT 30 S. Enteritidis cocktails were inoculated onto almond and pine nut kernels, respectively, followed by treatments with NIR or 2% LA spray alone, NIR with distilled water spray (NIR-DW), and NIR with 2% LA spray (NIR-LA). Although surface temperatures of nuts treated with NIR were higher than those subjected to NIR-DW or NIR-LA treatment, more S. Enteritidis survived after NIR treatment alone. The effectiveness of NIR-DW and NIR-LA was similar, but significantly more sublethally injured cells were recovered from NIR-DW-treated samples. We confirmed that the enhanced bactericidal effect of the NIR-LA combination may not be attributable to cell membrane damage per se. NIR heat treatment might allow S. Enteritidis cells to become permeable to applied LA solution. The NIR-LA treatment (5 min) did not significantly (P > 0.05) cause changes in the lipid peroxidation parameters, total phenolic contents, color values, moisture contents, and sensory attributes of nut kernels. Given the results of the present study, NIR-LA treatment may be a potential intervention for controlling food-borne pathogens on nut kernel products. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  2. Isolating stem cells in the inter-follicular epidermis employing synchrotron radiation-based Fourier-transform infrared microspectroscopy and focal plane array imaging.

    Science.gov (United States)

    Patel, Imran I; Harrison, Wesley J; Kerns, Jemma G; Filik, Jacob; Wehbe, Katia; Carmichael, Paul L; Scott, Andrew D; Philpott, Mike P; Frogley, Mark D; Cinque, Gianfelice; Martin, Francis L

    2012-10-01

    Normal function and physiology of the epidermis is maintained by the regenerative capacity of this tissue via adult stem cells (SCs). However, definitive identifying markers for SCs remain elusive. Infrared (IR) spectroscopy exploits the ability of cellular biomolecules to absorb in the mid-IR region (λ = 2.5-25 μm), detecting vibrational transitions of chemical bonds. In this study, we exploited the cell's inherent biochemical composition to discriminate SCs of the inter-follicular skin epidermis based on IR-derived markers. Paraffin-embedded samples of human scalp skin (n = 4) were obtained, and 10-μm thick sections were mounted for IR spectroscopy. Samples were interrogated in transmission mode using synchrotron radiation-based Fourier-transform IR (FTIR) microspectroscopy (15 × 15 μm) and also imaged employing globar-source FTIR focal plane array (FPA) imaging (5.4 × 5.4 μm). Dependent on the location of derived spectra, wavenumber-absorbance/intensity relationships were examined using unsupervised principal component analysis. This approach showed clear separation and spectral differences dependent on cell type. Spectral biomarkers concurrently associated with segregation of SCs, transit-amplifying cells and terminally-differentiated cells of epidermis were primarily PO(2)(-) vibrational modes (1,225 and 1,080 cm(-1)), related to DNA conformational alterations. FPA imaging coupled with hierarchical cluster analysis also indicated the presence of specific basal layer cells potentially originating from the follicular bulge, suggested by co-clustering of spectra. This study highlights PO (2) (-) vibrational modes as potential putative SC markers.

  3. Functional characterisation of an Arabidopsis gene strongly induced by ionising radiation: the gene coding the poly(ADP-ribose)polymerase-1 (AthPARP-1)

    International Nuclear Information System (INIS)

    Doucet-Chabeaud, G.

    2000-01-01

    Arabidopsis thaliana, the model-system in plant genetics, has been used to study the responses to DNA damage, experimentally introduced by γ-irradiation. We have characterised a radiation-induced gene coding a 111 kDa protein, AthPARP-1, homologous to the human poly(ADP-ribose)polymerase-1 (hPARP-1). As hPARP-1 is composed by three functional domain with characteristic motifs, AthPARP-1 binds to DNA bearing single-strand breaks and shows DNA damage-dependent poly(ADP-ribosyl)ation. The preferential expression of AthPARP-1 in mitotically active tissues is in agreement with a potential role in the maintenance of genome integrity during DNA replication, as proposed for its human counterpart. Transcriptional gene activation by ionising radiation of AthPARP-1 and AthPARP-2 genes is to date plant specific activation. Our expression analyses after exposure to various stress indicate that 1) AthPARP-1 and AthPARP-2 play an important role in the response to DNA lesions, particularly they are activated by genotoxic agents implicating the BER DNA repair pathway 2) AthPARP-2 gene seems to play an additional role in the signal transduction induced by oxidative stress 3) the observed expression profile of AthPARP-1 is in favour of the regulation of AthPARP-1 gene expression at the level of transcription and translation. This mode of regulation of AthPARP-1 protein biosynthesis, clearly distinct from that observed in animals, needs the implication of a so far unidentified transcription factor that is activated by the presence of DNA lesions. The major outcome of this work resides in the isolation and characterisation of such new transcription factor, which will provide new insight on the regulation of plant gene expression by genotoxic stress. (author) [fr

  4. Memory and the infrared

    Science.gov (United States)

    Gomez, Cesar; Letschka, Raoul

    2017-10-01

    Memory effects in scattering processes are described in terms of the asymptotic retarded fields. These fields are completely determined by the scattering data and the zero mode part is set by the soft photon theorem. The dressed asymptotic states defining an infrared finite S-matrix for charged particles can be defined as quantum coherent states using the corpuscular resolution of the asymptotic retarded fields. Imposing that the net radiated energy in the scattering is zero leads to the new set of conservation laws for the scattering S-matrix which are equivalent to the decoupling of the soft modes. The actual observability of the memory requires a non-vanishing radiated energy and could be described using the infrared part of the differential cross section that only depends on the scattering data and the radiated energy. This is the IR safe cross section with any number of emitted photons carrying total energy equal to the energy involved in the actual memory detection.

  5. Stirring Strongly Coupled Plasma

    CERN Document Server

    Fadafan, Kazem Bitaghsir; Rajagopal, Krishna; Wiedemann, Urs Achim

    2009-01-01

    We determine the energy it takes to move a test quark along a circle of radius L with angular frequency w through the strongly coupled plasma of N=4 supersymmetric Yang-Mills (SYM) theory. We find that for most values of L and w the energy deposited by stirring the plasma in this way is governed either by the drag force acting on a test quark moving through the plasma in a straight line with speed v=Lw or by the energy radiated by a quark in circular motion in the absence of any plasma, whichever is larger. There is a continuous crossover from the drag-dominated regime to the radiation-dominated regime. In the crossover regime we find evidence for significant destructive interference between energy loss due to drag and that due to radiation as if in vacuum. The rotating quark thus serves as a model system in which the relative strength of, and interplay between, two different mechanisms of parton energy loss is accessible via a controlled classical gravity calculation. We close by speculating on the implicati...

  6. Powerful infrared emitting diodes

    Directory of Open Access Journals (Sweden)

    Kogan L. M.

    2012-02-01

    Full Text Available Powerful infrared LEDs with emission wavelength 805 ± 10, 870 ± 20 and 940 ± 10 nm developed at SPC OED "OPTEL" are presented in the article. The radiant intensity of beam diode is under 4 W/sr in the continuous mode and under 100 W/sr in the pulse mode. The radiation power of wide-angle LEDs reaches 1 W in continuous mode. The external quantum efficiency of emission IR diodes runs up to 30%. There also has been created infrared diode modules with a block of flat Fresnel lenses with radiant intensity under 70 W/sr.

  7. Design features of a planar hybrid/permanent magnet strong-focusing undulator for Free Electron Laser (FEL) and Synchrotron Radiation (SR) applications

    Science.gov (United States)

    Tatchyn, Roman

    1997-05-01

    Insertion devices for Angstrom-wavelength Free Electron Laser (FEL) amplifiers driven by multi-GeV electron beams generally require distributed focusing substantially stronger than their natural focusing fields(C. Pellegrini, "A 4 to 0.1 nm FEL Based on the SLAC Linac," in Proc. Workshop on 4th Generation Light Sources, M.Cornacchia and H. Winick, eds., SSRL, Feb. 1992. p. 364 ff.)(R. Tatchyn, "Optimal Insertion Device Parameters for SASE FEL Operation," ibid., p. 605 ff.). Over the last several years a wide variety of focusing schemes and configurations have been proposed for undulators of this class, ranging from conventional current-driven quadrupoles external to the undulator magnets(R. Tatchyn, R. Boyce, K. Halbach, H.-D. Nuhn, J. Seeman, H. Winick, and C. Pellegrini, "Design Considerations for a 60 Meter Pure Permanent Magnet Undulator for the SLAC Linac Coherent Light Source (LCLS)," in Proceedings of the 1993 Particle Accelerator Conference, IEEE Catalog No. 93CH3279-7, 1608(1993).) to permanent magnet (PM) lattices inserted into the insertion device gap(R. Tatchyn, "Selected applications of planar permanent magnet multipoles in FEL insertion device design," NIM A341, 449(1994).)(A. A. Varfolomeev, A. H. Hairetdinov, "Advanced hybrid undulator schemes providing enhanced transverse e-beam focusing," ibid., p. 462.)(G. Travish, J. Rosenzweig, "Strong sextupole focussing in planar undulators," NIM A345, 585(1994).). In this paper we present design studies of a flexible hybrid/PM undulator with superimposed planar PM focusing proposed for a 1.5 Angstrom Linac Coherent Light Source (LCLS) undulator(S. Caspi, R. Schlueter, R. Tatchyn, "High-Field Strong-Focusing Undulator Designs for X-Ray Linac Coherent Light Source (LCLS) Applications," Proc. IEEE PAC95, Dallas, TX, May 1-5, 1995, SLAC-PUB-95-6885.)(R. Tatchyn, "Permanent Magnet Edge-Field Quadrupole," US Patent 5,596,304.) driven by an electron beam with a 1 mm-mr normalized emittance(R. Tatchyn et al, NIM A

  8. Integration Pattern of Human Papillomavirus Is a Strong Prognostic Factor for Disease-Free Survival After Radiation Therapy in Cervical Cancer Patients.

    Science.gov (United States)

    Joo, Jungnam; Shin, Hye-Jin; Park, Boram; Park, Seog-Yun; Yoo, Chong-Woo; Yoon, Kyong-Ah; Kong, Sun-Young; Kim, Youn-Jae; Kim, Sang Soo; Kim, Joo-Young

    2017-07-01

    The standard chemoradiation therapy currently used for locally advanced cervical cancer (LACC) patients does not reflect the biological heterogeneity of this disease, and there is an increasing need for the development of biomarkers that can help guide the individualized treatment regimens. The purpose of this study was to investigate the prognostic value of the integration pattern of human papillomavirus (HPV) in LACC patients. The HPV integration pattern was determined by in situ hybridization and polymerase chain reaction, and the tumors were classified as the episomal pattern (group A), as the single-copy integrated or multicopy tandem repetition-integrated pattern (group B), or as undetectable HPV (group C). Ninety-eight LACC patients were included in a development dataset and 106 independent patients in a validation dataset. The multivariate Cox model was used to examine the effect of the HPV integration pattern on disease-free survival (DFS). The model was validated internally by the leave-one-out cross-validation method and externally by an independent dataset. After adjustment for significant prognostic factors (stage, histologic grade, histologic type, and tumor size), the HPV integration pattern was significantly associated with DFS in the development (P=.032) and validation (P=.023) datasets. Survival was worst in group C and best in group A. The multivariate model with HPV integration pattern as an explanatory variable showed good discrimination ability and could separate patients with different risk profiles. This study identified the HPV integration pattern, as determined by in situ hybridization and polymerase chain reaction, as a strong prognostic biomarker for DFS in LACC patients treated by chemoradiation therapy. This finding may open the possibility of personalized treatment of these patients. Copyright © 2017. Published by Elsevier Inc.

  9. Far-infrared radiation acutely increases nitric oxide production by increasing Ca{sup 2+} mobilization and Ca{sup 2+}/calmodulin-dependent protein kinase II-mediated phosphorylation of endothelial nitric oxide synthase at serine 1179

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jung-Hyun; Lee, Sangmi [Department of Molecular Medicine and Ewha Medical Research Institute, Ewha Womans University Medical School, Seoul 158-710 (Korea, Republic of); Cho, Du-Hyong [Department of Neuroscience, School of Medicine, Konkuk University, Seoul 143-701 (Korea, Republic of); Park, Young Mi [Department of Molecular Medicine and Ewha Medical Research Institute, Ewha Womans University Medical School, Seoul 158-710 (Korea, Republic of); Kang, Duk-Hee [Division of Nephrology, Department of Internal Medicine, Ewha Womans University Medical School, Seoul 158-710 (Korea, Republic of); Jo, Inho, E-mail: inhojo@ewha.ac.kr [Department of Molecular Medicine and Ewha Medical Research Institute, Ewha Womans University Medical School, Seoul 158-710 (Korea, Republic of)

    2013-07-12

    Highlights: •Far-infrared (FIR) radiation increases eNOS-Ser{sup 1179} phosphorylation and NO production in BAEC. •CaMKII and PKA mediate FIR-stimulated increases in eNOS-Ser{sup 1179} phosphorylation. •FIR increases intracellular Ca{sup 2+} levels. •Thermo-sensitive TRPV Ca{sup 2+} channels are unlikely to be involved in the FIR-mediated eNOS-Ser{sup 1179} phosphorylation pathway. -- Abstract: Repeated thermal therapy manifested by far-infrared (FIR) radiation improves vascular function in both patients and mouse model with coronary heart disease, but its underlying mechanism is not fully understood. Using FIR as a thermal therapy agent, we investigate the molecular mechanism of its effect on endothelial nitric oxide synthase (eNOS) activity and NO production. FIR increased the phosphorylation of eNOS at serine 1179 (eNOS-Ser{sup 1179}) in a time-dependent manner (up to 40 min of FIR radiation) in bovine aortic endothelial cells (BAEC) without alterations in eNOS expression. This increase was accompanied by increases in NO production and intracellular Ca{sup 2+} levels. Treatment with KN-93, a selective inhibitor of Ca{sup 2+}/calmodulin-dependent protein kinase II (CaMKII) and H-89, a protein kinase A inhibitor, inhibited FIR radiation-stimulated eNOS-Ser{sup 1179} phosphorylation. FIR radiation itself also increased the temperature of culture medium. As transient receptors potential vanilloid (TRPV) ion channels are known to be temperature-sensitive calcium channels, we explore whether TRPV channels mediate these observed effects. Reverse transcription-PCR assay revealed two TRPV isoforms in BAEC, TRPV2 and TRPV4. Although ruthenium red, a pan-TRPV inhibitor, completely reversed the observed effect of FIR radiation, a partial attenuation (∼20%) was found in cells treated with Tranilast, TRPV2 inhibitor. However, ectopic expression of siRNA of TRPV2 showed no significant alteration in FIR radiation-stimulated eNOS-Ser{sup 1179} phosphorylation. This

  10. Untangling the methane chemistry in interstellar and solar system ices toward ionizing radiation: a combined infrared and reflectron time-of-flight analysis.

    Science.gov (United States)

    Abplanalp, Matthew J; Jones, Brant M; Kaiser, Ralf I

    2018-02-21

    Pure methane (CH 4 /CD 4 ) ices were exposed to three ionizing radiation sources at 5.5 K under ultrahigh vacuum conditions to compare the complex hydrocarbon spectrum produced across several interstellar environments. These irradiation sources consisted of energetic electrons to simulate secondary electrons formed in the track of galactic cosmic rays (GCRs), Lyman α (10.2 eV; 121.6 nm) photons simulated the internal VUV field in a dense cloud, and broadband (112.7-169.8 nm; 11.0-7.3 eV) photons which mimic the interstellar ultra-violet field. The in situ chemical evolution of the ices was monitored via Fourier transform infrared spectroscopy (FTIR) and during heating via mass spectrometry utilizing a quadrupole mass spectrometer with an electron impact ionization source (EI-QMS) and a reflectron time-of-flight mass spectrometer with a photoionization source (PI-ReTOF-MS). The FTIR analysis detected six small hydrocarbon products from the three different irradiation sources: propane [C 3 H 8 (C 3 D 8 )], ethane [C 2 H 6 (C 2 D 6 )], the ethyl radical [C 2 H 5 (C 2 D 5 )], ethylene [C 2 H 4 (C 2 D 4 )], acetylene [C 2 H 2 (C 2 D 2 )], and the methyl radical [CH 3 (CD 3 )]. The sensitive PI-ReTOF-MS analysis identified a complex array of products with different products being detected between experiments with general formulae: C n H 2n+2 (n = 4-8), C n H 2n (n = 3-9), C n H 2n-2 (n = 3-9), C n H 2n-4 (n = 4-9), and C n H 2n-6 (n = 6-7) from electron irradiation and C n H 2n+2 (n = 4-8), C n H 2n (n = 3-10), C n H 2n-2 (n = 3-11), C n H 2n-4 (n = 4-11), C n H 2n-6 (n = 5-11), and C n H 2n-8 (n = 6-11) from broadband photolysis and Lyman α photolysis. These experiments show that even the simplest hydrocarbon can produce important complex hydrocarbons such as C 3 H 4 and C 4 H 6 isomers. Distinct isomers from these groups have been shown to be important reactants in the synthesis of polycyclic aromatic hydrocarbons like indene (C 9 H 8 ) and naphthalene (C 10 H 8

  11. Microprobing the Molecular Spatial Distribution and Structural Architecture of Feed-type Sorghum Seed Tissue (Sorghum Bicolor L.) using the Synchrotron Radiation Infrared Microspectroscopy Technique

    Energy Technology Data Exchange (ETDEWEB)

    P Yu

    2011-12-31

    Sorghum seed (Sorghum bicolor L.) has unique degradation and fermentation behaviours compared with other cereal grains such as wheat, barley and corn. This may be related to its cell and cell-wall architecture. The advanced synchrotron radiation infrared microspectroscopy (SR-IMS) technique enables the study of cell or living cell biochemistry within cellular dimensions. The objective of this study was to use the SR-IMS imaging technique to microprobe molecular spatial distribution and cell architecture of the sorghum seed tissue comprehensively. High-density mapping was carried out using SR-IMS on beamline U2B at the National Synchrotron Light Source (Brookhaven National Laboratory, NY, USA). Molecular images were systematically recorded from the outside to the inside of the seed tissue under various chemical functional groups and their ratios [peaks at {approx}1725 (carbonyl C=O ester), 1650 (amide I), 1657 (protein secondary structure {alpha}-helix), 1628 (protein secondary structure {beta}-sheet), 1550 (amide II), 1515 (aromatic compounds of lignin), 1428, 1371, 1245 (cellulosic compounds in plant seed tissue), 1025 (non-structural CHO, starch granules), 1246 (cellulosic material), 1160 (CHO), 1150 (CHO), 1080 (CHO), 930 (CHO), 860 (CHO), 3350 (OH and NH stretching), 2960 (CH{sub 3} anti-symmetric), 2929 (CH{sub 2} anti-symmetric), 2877 (CH{sub 3} symmetric) and 2848 cm{sup -1} (CH{sub 2} asymmetric)]. The relative protein secondary structure {alpha}-helix to {beta}-sheet ratio image, protein amide I to starch granule ratio image, and anti-symmetric CH{sub 3} to CH{sub 2} ratio image were also investigated within the intact sorghum seed tissue. The results showed unique cell architecture, and the molecular spatial distribution and intensity in the sorghum seed tissue (which were analyzed through microprobe molecular imaging) were generated using SR-IMS. This imaging technique and methodology has high potential and could be used for scientists to develop

  12. Microprobing the molecular spatial distribution and structural architecture of feed-type sorghum seed tissue (Sorghum Bicolor L.) using the synchrotron radiation infrared microspectroscopy technique.

    Science.gov (United States)

    Yu, Peiqiang

    2011-09-01

    Sorghum seed (Sorghum bicolor L.) has unique degradation and fermentation behaviours compared with other cereal grains such as wheat, barley and corn. This may be related to its cell and cell-wall architecture. The advanced synchrotron radiation infrared microspectroscopy (SR-IMS) technique enables the study of cell or living cell biochemistry within cellular dimensions. The objective of this study was to use the SR-IMS imaging technique to microprobe molecular spatial distribution and cell architecture of the sorghum seed tissue comprehensively. High-density mapping was carried out using SR-IMS on beamline U2B at the National Synchrotron Light Source (Brookhaven National Laboratory, NY, USA). Molecular images were systematically recorded from the outside to the inside of the seed tissue under various chemical functional groups and their ratios [peaks at ∼1725 (carbonyl C=O ester), 1650 (amide I), 1657 (protein secondary structure α-helix), 1628 (protein secondary structure β-sheet), 1550 (amide II), 1515 (aromatic compounds of lignin), 1428, 1371, 1245 (cellulosic compounds in plant seed tissue), 1025 (non-structural CHO, starch granules), 1246 (cellulosic material), 1160 (CHO), 1150 (CHO), 1080 (CHO), 930 (CHO), 860 (CHO), 3350 (OH and NH stretching), 2960 (CH(3) anti-symmetric), 2929 (CH(2) anti-symmetric), 2877 (CH(3) symmetric) and 2848 cm(-1) (CH(2) asymmetric)]. The relative protein secondary structure α-helix to β-sheet ratio image, protein amide I to starch granule ratio image, and anti-symmetric CH(3) to CH(2) ratio image were also investigated within the intact sorghum seed tissue. The results showed unique cell architecture, and the molecular spatial distribution and intensity in the sorghum seed tissue (which were analyzed through microprobe molecular imaging) were generated using SR-IMS. This imaging technique and methodology has high potential and could be used for scientists to develop specific cereal grain varieties with targeted food and

  13. 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.

  14. Infrared thermography

    CERN Document Server

    Meola, Carosena

    2012-01-01

    This e-book conveys information about basic IRT theory, infrared detectors, signal digitalization and applications of infrared thermography in many fields such as medicine, foodstuff conservation, fluid-dynamics, architecture, anthropology, condition monitoring, non destructive testing and evaluation of materials and structures.

  15. Infrared Devices And Techniques (Revision

    Directory of Open Access Journals (Sweden)

    Rogalski A.

    2014-12-01

    Full Text Available The main objective of this paper is to produce an applications-oriented review covering infrared techniques and devices. At the beginning infrared systems fundamentals are presented with emphasis on thermal emission, scene radiation and contrast, cooling techniques, and optics. Special attention is focused on night vision and thermal imaging concepts. Next section concentrates shortly on selected infrared systems and is arranged in order to increase complexity; from image intensifier systems, thermal imaging systems, to space-based systems. In this section are also described active and passive smart weapon seekers. Finally, other important infrared techniques and devices are shortly described, among them being: non-contact thermometers, radiometers, LIDAR, and infrared gas sensors.

  16. Visible-Near Infrared (VNIR) and Shortwave Infrared (SWIR) Spectral Variability of Urban Materials

    Science.gov (United States)

    2013-03-01

    Spectrometry) The theory behind hyperspectral remote sensing is that the reflected solar radiation from Earth surfaces can be measured in hundreds of...INFRARED (VNIR) AND SHORTWAVE INFRARED (SWIR) SPECTRAL VARIABILITY OF URBAN MATERIALS by Kenneth G Fairbarn Jr March 2013 Thesis Advisor...2013 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE VISIBLE–NEAR INFRARED (VNIR) AND SHORTWAVE INFRARED (SWIR) SPECTRAL

  17. Radiative corrections in strong Coulomb fields

    International Nuclear Information System (INIS)

    Soff, G.

    1993-04-01

    Contributions to the electron Lamb shift in highly charged ions are summarized. Recent theoretical developments as well as current experimental results are considered. Special emphasis is laid on higher-order vacuum polarization corrections as well as on the nuclear size effect on the electron self energy. (orig.). 5 figs

  18. Infrared up-conversion telescope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented to an up-conversion infrared telescope (110) arranged for imaging an associated scene (130), wherein the up-conversion infrared telescope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein a first optical...... at the plane of the external image) which is denominated D2 and wherein D1 is larger than a second diameter D2 and wherein the telescope further comprises a third optical component (103) and a fourth optical component (104); arranged for re-imaging the first image into a second image of the back-focal plane...

  19. Infrared up-conversion microscope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented an up-conversion infrared microscope (110) arranged for imaging an associated object (130), wherein the up-conversion infrared microscope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein an objective optical...... component (100) has an entrance pupil with a first diameter D1, and an optical component system which is arranged for forming an external image (136) of the back-focal plane (132) of the objective optical component (100), which has a diameter (given by the diameter of a circle enclosing all optical paths...

  20. Infrared up-conversion telescope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented to an up-conversion infrared telescope (110) arranged for imaging an associated scene (130), wherein the up-conversion infrared telescope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein a first optical...... component (101) has an entrance pupil with a first diameter D1, and an optical component system which is arranged for forming an first image (136) of the back-focal plane (132) of the objective optical component (100), which has a diameter (given by the diameter of a circle enclosing all optical paths...

  1. Electromagnetic processes in strong crystalline fields

    CERN Multimedia

    2007-01-01

    We propose a number of new investigations on aspects of radiation from high energy electron and positron beams (10-300 GeV) in single crystals and amorphous targets. The common heading is radiation emission by electrons and positrons in strong electromagnetic fields, but as the setup is quite versatile, other related phenomena in radiation emission can be studied as well. The intent is to clarify the role of a number of important aspects of radiation in strong fields as e.g. observed in crystals. We propose to measure trident 'Klein-like' production in strong crystalline fields, 'crystalline undulator' radiation, 'sandwich' target phenomena, LPM suppression of pair production as well as axial and planar effects in contributions of spin to the radiation.

  2. Electromagnetic Processes in strong Crystalline Fields

    CERN Multimedia

    2007-01-01

    We propose a number of new investigations on aspects of radiation from high energy electron and positron beams (10-300 GeV) in single crystals and amorphous targets. The common heading is radiation emission by electrons and positrons in strong electromagnetic fields, but as the setup is quite versatile, other related phenomena in radiation emission can be studied as well. The intent is to clarify the role of a number of important aspects of radiation in strong fields as e.g. observed in crystals. We propose to measure trident 'Klein-like' production in strong crystalline fields, 'crystalline undulator' radiation, 'sandwich' target phenomena, LPM suppression of pair production as well as axial and planar effects in contributions of spin to the radiation.

  3. Effect of near-infrared-radiation reflective screen materials on ventilation requirement, crop transpiration and water use efficiency of a greenhouse rose crop

    NARCIS (Netherlands)

    Stanghellini, C.; Jianfeng, D.; Kempkes, F.L.K.

    2011-01-01

    The effect of Near Infrared (NIR)-reflective screen material on ventilation requirement, crop transpiration and water use efficiency of a greenhouse rose crop was investigated in an experiment whereby identical climate was ensured in greenhouse compartments installed with either NIR-reflective or

  4. The origin of the far-infrared continuum of z ~ 6 quasars. A radiative transfer model for SDSS J1148+5251

    NARCIS (Netherlands)

    Schneider, R.; Bianchi, S.; Valiante, R.; Risaliti, G.; Salvadori, S.

    Context. Understanding the history of formation of z > 6 quasars is a major challenge to theoretical models. Physical insights on the connection between the central black hole and its host galaxy can be gained by means of the quasar infrared properties. Aims: Here we investigate the origin of the

  5. The role of optical radiations in skin cancer.

    Science.gov (United States)

    Ayala, Fabrizio; Palla, Marco; Di Trolio, Rossella; Mozzillo, Nicola; Ascierto, Paolo A

    2013-01-01

    Purpose. Electromagnetic radiation with wavelength in the range 100 nm to 1 mm is known as optical radiation and includes ultraviolet radiation, the visible spectrum, and infrared radiation. The deleterious short- and long-term biological effects of ultraviolet radiation, including melanoma and other skin cancers, are well recognized. Infrared radiation may also have damaging biological effects. Methods. The objective of this review was to assess the literature over the last 15 years and to summarize correlations between exposure to optical radiation and the risk of melanoma and other cancers. Results. There is a clear correlation between exposure to UV radiation and the development of skin cancer. Most importantly, a strong association between artificial UV radiation exposure, for example, tanning devices, and the risk of melanoma and squamous cell carcinoma has been clearly demonstrated. There is no clear evidence that exposure to IR and laser radiation may increase the risk of skin cancer, although negative health effects have been observed. Conclusions. Preventative strategies that involve provision of public information highlighting the risks associated with exposure to sunlight remain important. In addition, precautionary measures that discourage exposure to tanning appliances are required, as is legislation to prevent their use during childhood.

  6. CINE: Comet INfrared Excitation

    Science.gov (United States)

    de Val-Borro, Miguel; Cordiner, Martin A.; Milam, Stefanie N.; Charnley, Steven B.

    2017-08-01

    CINE calculates infrared pumping efficiencies that can be applied to the most common molecules found in cometary comae such as water, hydrogen cyanide or methanol. One of the main mechanisms for molecular excitation in comets is the fluorescence by the solar radiation followed by radiative decay to the ground vibrational state. This command-line tool calculates the effective pumping rates for rotational levels in the ground vibrational state scaled by the heliocentric distance of the comet. Fluorescence coefficients are useful for modeling rotational emission lines observed in cometary spectra at sub-millimeter wavelengths. Combined with computational methods to solve the radiative transfer equations based, e.g., on the Monte Carlo algorithm, this model can retrieve production rates and rotational temperatures from the observed emission spectrum.

  7. Effects of near infrared laser radiation associated with photoabsorbing cream in preventing white spot lesions around orthodontic brackets: an in vitro study.

    Science.gov (United States)

    Lacerda, Ângela Sueli Soares Braga; Hanashiro, Fernando Seishim; de Sant'Anna, Giselle Rodrigues; Steagall Júnior, Washington; Barbosa, Patrícia Silva; de Souza-Zaroni, Wanessa Christine

    2014-12-01

    The present study aims to investigate the effect of a low-power infrared laser on the inhibition of bovine enamel demineralization around orthodontic brackets. Near infrared lasers have been suggested as alternative approaches because they may produce an increase in resistance to dental caries. Forty-eight blocks of enamel obtained from bovine incisor teeth were divided into six groups: Group 1 (control), without treatment; Group 2 (C), photoabsorbing cream; Group 3 (CF), photoabsorbing cream with fluoride; Group 4 (L), irradiation with low-level infrared laser (λ=830 nm) at an energy density of 4.47 J/cm2; Group 5 (L+C), photoabsorbing cream followed by low-level infrared laser irradiation; and Group 6 (L+CF), photoabsorbing cream with fluoride followed by low-level infrared laser irradiation. After these procedures, the enamel blocks received an assortment of orthodontic brackets and were then submitted to pH cycling to simulate a highly cariogenic challenge. The enamel surface demineralization around the orthodontic brackets, according to the different treatments, was quantified by fluorescence loss analysis by quantitative light-induced fluorescence (QLF). The fluorescence loss, expressed as ΔF (percentage of loss fluorescence), was statistically examined by analysis of variance and the Tukey test. The control group (-10.48±2.85) was statistically similar to Group C (-14.52±7.80), which presented the lowest values of ΔF when compared with Groups FC (-3.67±3.21), L (-2.79±1.68), CL (-1.05±0:50), and CFL (-0.60±0:43). However, Groups FC, L, CL, and CFL showed no statistically significant differences among them. It can be concluded that both the low-level infrared laser and photoabsorbing cream with fluoride were effective in inhibiting the development of caries in enamel around orthodontic brackets, even in situations of high cariogenic challenge.

  8. The CubeSat Infrared Atmospheric Sounder (CIRAS), Pathfinder for the Earth Observing Nanosatellite-Infrared (EON-IR)

    OpenAIRE

    Pagano, Thomas S.; Rider, David; Teixeira, Joao; Aumann, Hartmut; Rud, Mayer; Pereira, John; Furlong, David; Mamula, Dan

    2016-01-01

    The CubeSat Infrared Atmospheric Sounder (CIRAS) will measure upwelling infrared radiation of the Earth in the Midwave Infrared (MWIR) region of the spectrum from space on a CubeSat. CIRAS will demonstrate two new infrared sounding technologies. The first is a 2D array of High Operating Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost, low noise and higher operating temperatures than traditional materials. The detectors are hybridized to a ...

  9. Infrared and reflectron time-of-flight mass spectroscopic study on the synthesis of glycolaldehyde in methanol (CH3OH) and methanol-carbon monoxide (CH3OH-CO) ices exposed to ionization radiation.

    Science.gov (United States)

    Maity, Surajit; Kaiser, Ralf I; Jones, Brant M

    2014-01-01

    We present conclusive evidence on the formation of glycolaldehyde (HOCH2CHO) synthesized within astrophysically relevant ices of methanol (CH3OH) and methanol-carbon monoxide (CH3OH-CO) upon exposure to ionizing radiation at 5.5 K. The radiation induced chemical processes of the ices were monitored on line and in situ via infrared spectroscopy which was complimented by temperature programmed desorption studies post irradiation, utilizing highly sensitive reflectron time-of-flight mass spectrometry coupled with single photon fragment free photoionization (ReTOF-PI) at 10.49 eV. Specifically, glycolaldehyde was observed via the v14 band and further enhanced with the associated frequency shifts of the carbonyl stretching mode observed in irradiated isotopologue ice mixtures. Furthermore, experiments conducted with mixed isotopic ices of methanol-carbon monoxide (13CH3OH-CO, CH3(18)OH-CO, CD3OD-13CO and CH3OH-C18O) provide solid evidence of at least three competing reaction pathways involved in the formation of glycolaldehyde via non-equilibrium chemistry, which were identified as follows: (i) radical-radical recombination of HCO and CH2OH formed via decomposition of methanol--the "two methanol pathway"; (ii) via the reaction of one methanol unit (CH2OH from the decomposition of CH3OH) with one carbon monoxide unit (HCO from the hydrogenation of CO)--the "one methanol, one carbon monoxide pathway"; and (iii) formation via hydrogenation of carbon monoxide resulting in radicals of HCO and CH2OH--the "two carbon monoxide pathway". In addition, temperature programmed desorption studies revealed an increase in the amount of glycolaldehyde formed, suggesting further thermal chemistry of trapped radicals within the ice matrix. Sublimation of glycolaldehyde during the warm up was also monitored via ReTOF-PI and validated via the mutual agreement of the associated isotopic frequency shifts within the infrared band positions and the identical sublimation profiles obtained from

  10. Synthesis and Near-Infrared Luminescence of a Deuterated Conjugated Porphyrin Dimer for Probing the Mechanism of Non-Radiative Deactivation (Postprint)

    National Research Council Canada - National Science Library

    Rogers, Joy E; Fleitz, Paul A; Frampton, Michael J; Anderson, Harry L; Accorsi, Gianluca; Armaroli, Nicola; McEwan, Kenneth J

    2007-01-01

    .... However their ultrafast S(sub-1)-S(sub-0) deactivation limits potential applications. We have synthesised a deuterated fused porphyrin dimer to test whether deuteration influences the rate of non-radiative deactivation...

  11. Aerosol radiative effects in the ultraviolet, visible, and near-infrared spectral ranges using long-term aerosol data series over the Iberian Peninsula

    OpenAIRE

    Mateos, David; Anton, Manuel; Toledano, Carlos; Cachorro, Victoria; Alados-Arboledas, Lucas; Sorribas, Mar; Costa, Maria João; Baldasano, José

    2014-01-01

    A better understanding of the aerosol radiative properties is a crucial challenge for climate change studies. This study aims to provide a complete characterization of aerosol radiative effects in different spectral ranges within the shortwave (SW) solar spectrum. For this purpose, long-term datasets of aerosol properties from six AERONET stations located in the Iberian Peninsula (Southwestern Europe) are analyzed in term of climatology characterization and ...

  12. Laser-induced plasma from pure and doped water-ice at high fluence by ultraviolet and infrared radiation - art. no. 70050X

    DEFF Research Database (Denmark)

    Schou, Jørgen; Matei, A.; Rodrigo, Katarzyna Agnieszka

    2008-01-01

    Ice made of ultrapure water or water doped with 1 % polymer (polyethylene glycol, "PEG") was irradiated by laser light with fluences between 2 and 80 J/cm(2) in the ultraviolet (UV) regime at 355 nm and in the infrared (IR) regime at 1064 nm in vacuum. In the UV regime there is a threshold for pl...... of ionization breakdown at the ice surface....

  13. Far infrared peculiar behavior of quasars

    International Nuclear Information System (INIS)

    Liu Yulin; Liu Jiying

    1988-09-01

    Many quasars possibly have nebulous envelopes with far infrared radiation. These nebulosities may be similar to fuzz in the optical region in morphology. These quasars have many properties in common. (author). Refs, 3 figs

  14. Strong-interaction nonuniversality

    International Nuclear Information System (INIS)

    Volkas, R.R.; Foot, R.; He, X.; Joshi, G.C.

    1989-01-01

    The universal QCD color theory is extended to an SU(3) 1 direct product SU(3) 2 direct product SU(3) 3 gauge theory, where quarks of the ith generation transform as triplets under SU(3)/sub i/ and singlets under the other two factors. The usual color group is then identified with the diagonal subgroup, which remains exact after symmetry breaking. The gauge bosons associated with the 16 broken generators then form two massive octets under ordinary color. The interactions between quarks and these heavy gluonlike particles are explicitly nonuniversal and thus an exploration of their physical implications allows us to shed light on the fundamental issue of strong-interaction universality. Nonuniversality and weak flavor mixing are shown to generate heavy-gluon-induced flavor-changing neutral currents. The phenomenology of these processes is studied, as they provide the major experimental constraint on the extended theory. Three symmetry-breaking scenarios are presented. The first has color breaking occurring at the weak scale, while the second and third divorce the two scales. The third model has the interesting feature of radiatively induced off-diagonal Kobayashi-Maskawa matrix elements

  15. Infrared Thermometer

    Science.gov (United States)

    1991-01-01

    Diatek Corporation, San Diego, CA and the Jet Propulsion Lab developed the Diatek Model 7000 aural thermometer which weighs only eight ounces, and measures temperature in less than two seconds using infrared astronomy technology to measure the amount of infrared energy emitted by the eardrum (the same way temperature of stars and planets is measured). This method avoids contact with mucous membranes, virtually eliminating the possibility of cross infection, and permits temperature measurement of newborn, critically ill, or incapacitated patients. Diatek Corporation was purchased by Welch Allyn Inc. The Diatek Model 7000 is now marketed as SureTemp.

  16. An infrared view of high Tc superconductors

    International Nuclear Information System (INIS)

    Tanner, D.B.; Timusk, T.; McMaster Univ., Hamilton, ON

    1989-01-01

    Studies of the infrared properties of the high T c superconductors are reviewed, with particular emphasis on attempts to determine the energy gap by far infrared spectroscopy and on the properties of the strong absorption that occurs in the mid infrared. The authors argue that this mid-infrared absorption is a direct particle-hole excitation rather than a Holstein emission process. In addition, they conclude that although the energy gap is not easily observed, several recent experiments place it in the weak to moderate strong coupling range

  17. 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

  18. Infrared Absorption Spectra, Radiative Efficiencies, and Global Warming Potentials of Newly-Detected Halogenated Compounds: CFC-113a, CFC-112 and HCFC-133a

    Directory of Open Access Journals (Sweden)

    Maryam Etminan

    2014-07-01

    Full Text Available CFC-113a (CF3CCl3, CFC-112 (CFCl2CFCl2 and HCFC-133a (CF3CH2Cl are three newly detected molecules in the atmosphere that are almost certainly emitted as a result of human activity. It is important to characterise the possible contribution of these gases to radiative forcing of climate change and also to provide information on the CO2-equivalence of their emissions. We report new laboratory measurements of absorption cross-sections of these three compounds at a resolution of 0.01 cm−1 for two temperatures 250 K and 295 K in the spectral range of 600–1730 cm−1. These spectra are then used to calculate the radiative efficiencies and global warming potentials (GWP. The radiative efficiencies are found to be between 0.15 and 0.3 W∙m−2∙ppbv−1. The GWP for a 100 year time horizon, relative to carbon dioxide, ranges from 340 for the relatively short-lived HCFC-133a to 3840 for the longer-lived CFC-112. At current (2012 concentrations, these gases make a trivial contribution to total radiative forcing; however, the concentrations of CFC-113a and HCFC-133a are continuing to increase. The 2012 CO2-equivalent emissions, using the GWP (100, are estimated to be about 4% of the current global CO2-equivalent emissions of HFC-134a.

  19. The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 3: Quantification of the mid- and near-infrared water vapor continuum in the 2500 to 7800 cm−1 spectral range under atmospheric conditions

    Directory of Open Access Journals (Sweden)

    A. Reichert

    2016-09-01

    Full Text Available We present a first quantification of the near-infrared (NIR water vapor continuum absorption from an atmospheric radiative closure experiment carried out at the Zugspitze (47.42° N, 10.98° E; 2964 m a.s.l.. Continuum quantification is achieved via radiative closure using radiometrically calibrated solar Fourier transform infrared (FTIR absorption spectra covering the 2500 to 7800 cm−1 spectral range. The dry atmospheric conditions at the Zugspitze site (IWV 1.4 to 3.3 mm enable continuum quantification even within water vapor absorption bands, while upper limits for continuum absorption can be provided in the centers of window regions. Throughout 75 % of the 2500 to 7800 cm−1 spectral range, the Zugspitze results agree within our estimated uncertainty with the widely used MT_CKD 2.5.2 model (Mlawer et al., 2012. In the wings of water vapor absorption bands, our measurements indicate about 2–5 times stronger continuum absorption than MT_CKD, namely in the 2800 to 3000 cm−1 and 4100 to 4200 cm−1 spectral ranges. The measurements are consistent with the laboratory measurements of Mondelain et al. (2015, which rely on cavity ring-down spectroscopy (CDRS, and the calorimetric–interferometric measurements of Bicknell et al. (2006. Compared to the recent FTIR laboratory studies of Ptashnik et al. (2012, 2013, our measurements are consistent within the estimated errors throughout most of the spectral range. However, in the wings of water vapor absorption bands our measurements indicate typically 2–3 times weaker continuum absorption under atmospheric conditions, namely in the 3200 to 3400, 4050 to 4200, and 6950 to 7050 cm−1 spectral regions.

  20. Infrared imaging of the crime scene: possibilities and pitfalls

    NARCIS (Netherlands)

    Edelman, Gerda J.; Hoveling, Richelle J. M.; Roos, Martin; van Leeuwen, Ton G.; Aalders, Maurice C. G.

    2013-01-01

    All objects radiate infrared energy invisible to the human eye, which can be imaged by infrared cameras, visualizing differences in temperature and/or emissivity of objects. Infrared imaging is an emerging technique for forensic investigators. The rapid, nondestructive, and noncontact features of

  1. Infrared retina

    Science.gov (United States)

    Krishna, Sanjay [Albuquerque, NM; Hayat, Majeed M [Albuquerque, NM; Tyo, J Scott [Tucson, AZ; Jang, Woo-Yong [Albuquerque, NM

    2011-12-06

    Exemplary embodiments provide an infrared (IR) retinal system and method for making and using the IR retinal system. The IR retinal system can include adaptive sensor elements, whose properties including, e.g., spectral response, signal-to-noise ratio, polarization, or amplitude can be tailored at pixel level by changing the applied bias voltage across the detector. "Color" imagery can be obtained from the IR retinal system by using a single focal plane array. The IR sensor elements can be spectrally, spatially and temporally adaptive using quantum-confined transitions in nanoscale quantum dots. The IR sensor elements can be used as building blocks of an infrared retina, similar to cones of human retina, and can be designed to work in the long-wave infrared portion of the electromagnetic spectrum ranging from about 8 .mu.m to about 12 .mu.m as well as the mid-wave portion ranging from about 3 .mu.m to about 5 .mu.m.

  2. Application of Far Infrared Radiation and Ethanol Vapor as Alternative Treatment Methods for Reduction of Salmonella enterica Tennessee in Dried, Ground Spices

    OpenAIRE

    Nimitz Jr, Stephen Clark

    2013-01-01

    The consumption of spiced food is steadily increasing, subsequently leading to increased incidence of spice-related food illnesses. Many outbreaks can be traced to human pathogens that can survive in low moisture content of spices, prompting development of additional inactivation treatments that reduce bacterial pathogens while maintaining spice quality. Spices are currently treated by fumigation with ethylene oxide, pasteurization with ionizing radiation, or steam treatment. However, these t...

  3. Molecular Evolution of the Infrared Sensory Gene TRPA1 in Snakes and Implications for Functional Studies

    Science.gov (United States)

    Jiang, Ke; Zhang, Peng

    2011-01-01

    TRPA1 is a calcium ion channel protein recently identified as the infrared receptor in pit organ-containing snakes. Therefore, understanding the molecular evolution of TRPA1 may help to illuminate the origin of “heat vision” in snakes and reveal the molecular mechanism of infrared sensitivity for TRPA1. To this end, we sequenced the infrared sensory gene TRPA1 in 24 snake species, representing nine snake families and multiple non-snake outgroups. We found that TRPA1 is under strong positive selection in the pit-bearing snakes studied, but not in other non-pit snakes and non-snake vertebrates. As a comparison, TRPV1, a gene closely related to TRPA1, was found to be under strong purifying selection in all the species studied, with no difference in the strength of selection between pit-bearing snakes and non-pit snakes. This finding demonstrates that the adaptive evolution of TRPA1 specifically occurred within the pit-bearing snakes and may be related to the functional modification for detecting infrared radiation. In addition, by comparing the TRPA1 protein sequences, we identified 11 amino acid sites that were diverged in pit-bearing snakes but conserved in non-pit snakes and other vertebrates, 21 sites that were diverged only within pit-vipers but conserved in the remaining snakes. These specific amino acid substitutions may be potentially functional important for infrared sensing. PMID:22163322

  4. Far-infrared line images of dwarf galaxies

    Science.gov (United States)

    Poglitsch, A.; Geis, N.; Herrmann, F.; Madden, S. C.; Stacey, G. J.; Townes, C. H.; Genzel, R.

    1993-01-01

    Irregular dwarf galaxies are about ten times more widespread in the universe than regular spiral galaxies. They are characterized by a relatively low metallicity, i.e., lower abundance of the heavier elements (metals) with respect to hydrogen than in the solar neighborhood. These heavier elements in the form of molecules, atoms, or ions, which have radiative transitions in the infrared play a decisive role in the energy balance of the ISM and thereby for the formation of stars. Dwarf galaxies are thus model cases for the physical conditions in the early phase of the universe. Large Magellanic Cloud: 30 Doradus. The two nearest dwarf galaxies are the Magellanic clouds at a distance approximately 50 kpc. The LMC contains 30 Dor, a region with young, extremely massive stars which strongly interact with the surrounding ISM on account of their stellar winds and intense UV radiation. 30 Dor is the brightest object in the LMC at almost all wavelengths.

  5. Infrared shield facilitates optical pyrometer measurements

    Science.gov (United States)

    Eichenbrenner, F. F.; Illg, W.

    1965-01-01

    Water-cooled shield facilitates optical pyrometer high temperature measurements of small sheet metal specimens subjected to tensile stress in fatigue tests. The shield excludes direct or reflected radiation from one face of the specimen and permits viewing of the infrared radiation only.

  6. Nonionizing radiation and health

    International Nuclear Information System (INIS)

    Suess, M.J.

    1985-01-01

    While a great deal of work has been done by international bodies to establish permissible levels for ionizing radiation, much less attention has been paid to the nonionizing forms of radiation and their possible health effects. Taking into account that equipment producing such radiation is now widely used both in the house and in industry, the paper presents the possible health effects of ultraviolet, visible, laser, infrared and microwave radiation, of electric and magnetic fields and of the ultrasound waves

  7. Superiority of terahertz over infrared transmission through bandages and burn wound ointments

    Energy Technology Data Exchange (ETDEWEB)

    Suen, Jonathan Y., E-mail: j.suen@duke.edu; Padilla, Willie J. [Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708 (United States)

    2016-06-06

    Terahertz electromagnetic waves have long been proposed to be ideal for spectroscopy and imaging through non-polar dielectric materials that contain no water. Terahertz radiation may thus be useful for monitoring burn and wound injury recovery, as common care treatments involve application of both a clinical dressing and topical ointment. Here, we investigate the optical properties of typical care treatments in the millimeter wave (150–300 GHz), terahertz (0.3–3 THz), and infrared (14.5–0.67 μm) ranges of the electromagnetic spectrum. We find that THz radiation realizes low absorption coefficients and high levels of transmission compared to infrared wavelengths, which were strongly attenuated. Terahertz imaging can enable safe, non-ionizing, noninvasive monitoring of the healing process directly through clinical dressings and recovery ointments, minimizing the frequency of dressing changes and thus increasing the rate of the healing process.

  8. Finding quantum effects in strong classical potentials

    Science.gov (United States)

    Hegelich, B. Manuel; Labun, Lance; Labun, Ou Z.

    2017-06-01

    The long-standing challenge to describing charged particle dynamics in strong classical electromagnetic fields is how to incorporate classical radiation, classical radiation reaction and quantized photon emission into a consistent unified framework. The current, semiclassical methods to describe the dynamics of quantum particles in strong classical fields also provide the theoretical framework for fundamental questions in gravity and hadron-hadron collisions, including Hawking radiation, cosmological particle production and thermalization of particles created in heavy-ion collisions. However, as we show, these methods break down for highly relativistic particles propagating in strong fields. They must therefore be improved and adapted for the description of laser-plasma experiments that typically involve the acceleration of electrons. Theory developed from quantum electrodynamics, together with dedicated experimental efforts, offer the best controllable context to establish a robust, experimentally validated foundation for the fundamental theory of quantum effects in strong classical potentials.

  9. Testing strong interaction theories

    International Nuclear Information System (INIS)

    Ellis, J.

    1979-01-01

    The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)

  10. KIC 8462852: THE INFRARED FLUX

    Energy Technology Data Exchange (ETDEWEB)

    Marengo, Massimo; Hulsebus, Alan [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Willis, Sarah [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2015-11-20

    We analyzed the warm Spitzer/IRAC data of KIC 8462852. We found no evidence of infrared excess at 3.6 μm and a small excess of 0.43 ± 0.18 mJy at 4.5 μm below the 3σ threshold necessary to claim a detection. The lack of strong infrared excess 2 years after the events responsible for the unusual light curve observed by Kepler further disfavors the scenarios involving a catastrophic collision in a KIC 8462852 asteroid belt, a giant impact disrupting a planet in the system or a population of dust-enshrouded planetesimals. The scenario invoking the fragmentation of a family of comets on a highly elliptical orbit is instead consistent with the lack of strong infrared excess found by our analysis.

  11. Synchrotron Radiation

    International Nuclear Information System (INIS)

    Asfour, F.I

    2000-01-01

    Synchrotron light is produced by electron accelerators combined with storage rings. This light is generated over a wide spectral region; from infra-red (IR) through the visible and vacuum ultraviolet (VUV), and into the X-ray region. For relativistic electrons (moving nearly with the speed of light), most radiation is concentrated in a small cone with an opening angle of 1/gamma(some 0.1 to 1 milliradian),where gamma is the electron energy in units of rest energy (typically 10 3 -10 4 ). In synchrotron radiation sources (storage rings) highly relativistic electrons are stored to travel along a circular path for many hours. Radiation is caused by transverse acceleration due to magnetic forces(bending magnets). The radiation is emitted in pulses of 10-20 picosecond, separated by some 2 nanosecond or longer separation

  12. Research Directed at Developing a Classical Theory to Describe Isotope Separation of Polyatomic Molecules Illuminated by Intense Infrared Radiation. Final Report for period May 7, 1979 to September 30, 1979; Extension December 31, 1997

    Science.gov (United States)

    Lamb, W. E. Jr.

    1981-12-01

    This final report describes research on the theory of isotope separation produced by the illumination of polyatomic molecules by intense infrared laser radiation. This process is investigated by treating the molecule, sulfur hexafluoride, as a system of seven classical particles that obey the Newtonian equations of motion. A minicomputer is used to integrate these differential equations. The particles are acted on by interatomic forces, and by the time-dependent electric field of the laser. We have a very satisfactory expression for the interaction of the laser and the molecule which is compatible with infrared absorption and spectroscopic data. The interatomic potential is capable of improvement, and progress on this problem is still being made. We have made several computer runs of the dynamical behavior of the molecule using a reasonably good model for the interatomic force law. For the laser parameters chosen, we find that typically the molecule passes quickly through the resonance region into the quasi-continuum and even well into the real continuum before dissociation actually occurs. When viewed on a display terminal, the motions are exceedingly complex. As an aid to the visualization of the process, we have made a number of 16 mm movies depicting a three-dimensional representation of the motion of the seven particles. These show even more clearly the enormous complexity of the motions, and make clear the desirability of finding ways of characterizing the motion in simple ways without giving all of the numerical detail. One of the ways to do this is to introduce statistical parameters such as a temperature associated with the distribution of kinetic energies of the single particle. We have made such an analysis of our data runs, and have found favorable indications that such methods will prove useful in keeping track of the dynamical histories.

  13. Research directed at developing a classical theory to describe isotope separation of polyatomic molecules illuminated by intense infrared radiation. Final report, May 7-September 30, 1979, extension December 31, 1979

    International Nuclear Information System (INIS)

    Lamb, W.E. Jr.

    1981-12-01

    This final report describes research on the theory of isotope separation produced by the illumination of polyatomic molecules by intense infrared laser radiation. This process is investigated by treating the molecule, sulfur hexafluoride, as a system of seven classical particles that obey the Newtonian equations of motion. A minicomputer is used to integrate these differential equations. The particles are acted on by interatomic forces, and by the time-dependent electric field of the laser. We have a very satisfactory expression for the interaction of the laser and the molecule which is compatible with infrared absorption and spectroscopic data. The interatomic potential is capable of improvement, and progress on this problem is still being made. We have made several computer runs of the dynamical behavior of the molecule using a reasonably good model for the interatomic force law. For the laser parameters chosen, we find that typically the molecule passes quickly through the resonance region into the quasi-continuum and even well into the real continuum before dissociation actually occurs. When viewed on a display terminal, the motions are exceedingly complex. As an aid to the visualization of the process, we have made a number of 16 mm movies depicting a three-dimensional representation of the motion of the seven particles. These show even more clearly the enormous complexity of the motions, and make clear the desirability of finding ways of characterizing the motion in simple ways without giving all of the numerical detail. One of the ways to do this is to introduce statistical parameters such as a temperature associated with the distribution of kinetic energies of the single particle. We have made such an analysis of our data runs, and have found favorable indications that such methods will prove useful in keeping track of the dynamical histories

  14. High-pressure measurements of hydrogen phase IV using synchrotron infrared spectroscopy.

    Science.gov (United States)

    Zha, Chang-sheng; Liu, Zhenxian; Ahart, Muhtar; Boehler, Reinhard; Hemley, Russell J

    2013-05-24

    Phase IV of dense solid hydrogen has been identified by its infrared spectrum using high-pressure synchrotron radiation techniques. The spectrum exhibits a sharp vibron band at higher frequency and lower intensity than that for phase III, indicating the stability of molecular H(2) with decreased intermolecular interactions and charge transfer between molecules. A low-frequency vibron having a strong negative pressure shift indicative of strongly interacting molecules is also observed. The character of the spectrum is consistent with an anisotropic, mixed layer structure related to those recently predicted theoretically. Phase IV was found to be stable from 220 GPa (300 K) to at least 340 GPa (near 200 K), with the I-III-IV triple point located. Infrared transmission observed to the lowest photon energies measured places constraints on the electronic properties of the phase.

  15. Infrared Radiation as Heat Transfer Mechanism of High Quality in Heating Processes La radiación infrarroja como mecanismo de transferencia de calor de alta calidad en procesos de calentamiento

    Directory of Open Access Journals (Sweden)

    Jose Luis Castañeda

    2012-12-01

    Full Text Available This paper tries to address the infrared radiation as a primary mechanismof heat transfer of high-quality in different heating processes, to highlightthe issues and applicability in the use, the characterization and design of thetechnologies powered by combustion systems. For this, it summarizes its phenomenology, definitions, assumptions and solutions; addresses some numericalmethods used to solve the Radiative Transfer Equation (RTE and its couplingto CFD codes (Computational Fluids Dynamics; as also the types of radiantequipment usually used, in especial the radiant tubes; as well as certain experimental methodologies used to characterize radiant systems, and some designmethodologies. It was found, that the flux model and the discrete transferare sufficient to give solution to the radiation heat transfer phenomenon withthe help of CFD codes, as well as the measuring device mainly used in experimental measurements is the radiometer, and the most practical designmethodology may be the optimization.En este artículo se pretende abordar la radiación infrarroja como un mecanismoprincipal de transferencia de calor de alta calidad en diferentes procesosde calentamiento, resaltar la pertenencia y problemática en el uso, la caracterizacióny el diseño de las tecnologías propias accionadas por sistemas decombustión. Para esto, se resume su fenomenología, sus definiciones, suposicionesy soluciones; se abordan algunos métodos numéricos utilizados parala solución de la ecuación de transferencia de radiación (Radiative TransferEquation (RTE y el acoplamiento de éstos a los códigos CFD (ComputationalFluids Dynamics; como también los tipos de equipos radiantes utilizadoscon mayor frecuencia, en especial los tubo radiantes; al igual que ciertas metodologíasexperimentales usadas para caracterizar los sistemas radiantes, yalgunas metodologías de diseño. Se encontró, que el modelo del flux y el de transferencias discretas son pertinentes

  16. Theoretical estimation and experimental design of high-intensity far-infrared to MM-wave coherent synchrotron radiation generated by short electron bunches at BFEL

    International Nuclear Information System (INIS)

    Zhu Junbiao; Li Yonggui; Xie Jialin

    2000-01-01

    Broadband continuous and high-intensity coherent synchrotron radiation (CSR) emitted from 4 ps electron bunches provided by the 30 MeV RF linac of Beijing FEL is analyzed and numerically calculated using an exact series expansion for the infinite integral of fractional modified Bessel function. CSR in the mm-wave and far-IR to mm-wave regions can be respectively generated by directly using these bunches and by applying those ones compressed to ≤=1 ps. The CSR powers, approximately as 10 8 -10 9 times as the SR ones, in the range from several hundred microwatts to milliwatts are dependent on chosen electron density distribution, wavelength range, and gathering angle. The power produced by rectangular bunches is greater than that generated by Gaussian ones. The shorter the bunch, the stronger the produced CSR, the greater the energy concentrated to the far-IR end. Experiments to generate CSR and measure the bunch length are designed

  17. Development of in situ Brillouin spectroscopy at high pressure and high temperature with synchrotron radiation and infrared laser heating system: Application to the Earth's deep interior

    Science.gov (United States)

    Murakami, Motohiko; Asahara, Yuki; Ohishi, Yasuo; Hirao, Naohisa; Hirose, Kei

    2009-05-01

    Seismic wave velocity profiles in the Earth provide one of the strongest constraints on structure, mineralogy and elastic properties of the Earth's deep interior. Accurate sound velocity data of deep Earth materials under relevant high-pressure and high-temperature conditions, therefore, are essential for interpretation of seismic data. Such information can be directly obtained from Brillouin scattering measurement. Here we describe an in situ Brillouin scattering system for measurements at high pressure and high temperature using a laser heated diamond anvil cell and synchrotron radiation for sample characterization. The system has been used with single-crystal and polycrystalline materials, and with glass and fluid phase. It provided high quality sound velocity and elastic data with X-ray diffraction data at high pressure and/or high temperature. Those combined techniques can potentially offer the essential information for resolving many remaining issues in mineral physics.

  18. New maxillofacial infrared detection technologies

    Energy Technology Data Exchange (ETDEWEB)

    Reshetnikov, A. P.; Kopylov, M. V.; Nasyrov, M. R., E-mail: marat.1994@me.com; Fisher, E. L.; Chernova, L. V. [Izhevsk State Medical Academy, Izhevsk, Russia (426034, Izhevsk, Kommunarov street, 281) (Russian Federation); Soicher, E. M. [Moscow State University of Medicine and Dentistry named after A.I. Evdokimov of the Ministry of Health of the Russian Federation, Moscow, Russia, (127473, Moscow, Delegatskaya str., 20/1) (Russian Federation)

    2015-11-17

    At the dental clinic the infrared range radiation spectrum of tissues was used to study the dynamics of local temperature and structure of the skin, subcutaneous fat, and other tissues of the maxillofacial area in adult healthy volunteers and patients. In particular, we studied the dynamics of local temperature of mucous membranes of the mouth, teeth, and places in the mouth and dental structures in the norm and in various pathological conditions of the lips, gums, teeth, tongue, palate, and cheeks before, during and after chewing food, drinking water, medication, and inhalation of air. High safety and informational content of infrared thermography are prospective for the development of diagnostics in medicine. We have 3 new methods for infrared detection protected by patents in Russia.

  19. New maxillofacial infrared detection technologies

    Science.gov (United States)

    Reshetnikov, A. P.; Kopylov, M. V.; Nasyrov, M. R.; Soicher, E. M.; Fisher, E. L.; Chernova, L. V.

    2015-11-01

    At the dental clinic the infrared range radiation spectrum of tissues was used to study the dynamics of local temperature and structure of the skin, subcutaneous fat, and other tissues of the maxillofacial area in adult healthy volunteers and patients. In particular, we studied the dynamics of local temperature of mucous membranes of the mouth, teeth, and places in the mouth and dental structures in the norm and in various pathological conditions of the lips, gums, teeth, tongue, palate, and cheeks before, during and after chewing food, drinking water, medication, and inhalation of air. High safety and informational content of infrared thermography are prospective for the development of diagnostics in medicine. We have 3 new methods for infrared detection protected by patents in Russia.

  20. Infrared up-conversion microscope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented an up-conversion infrared microscope (110) arranged for imaging an associated object (130), wherein the up-conversion infrared microscope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein an objective optical...... component (100) has an entrance pupil with a first diameter D1, and an optical component system which is arranged for forming an external image (136) of the back-focal plane (132) of the objective optical component (100), which has a diameter (given by the diameter of a circle enclosing all optical paths...... at the plane of the 10 external image) which is denominated D2 and wherein D1 is larger than a second diameter D2....

  1. Strong terahertz field generation, detection, and application

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki-Yong [Univ. of Maryland, College Park, MD (United States)

    2016-05-22

    This report describes the generation and detection of high-power, broadband terahertz (THz) radiation with using femtosecond terawatt (TW) laser systems. In particular, this focuses on two-color laser mixing in gases as a scalable THz source, addressing both microscopic and macroscopic effects governing its output THz yield and radiation profile. This also includes the characterization of extremely broad THz spectra extending from microwaves to infrared frequencies. Experimentally, my group has generated high-energy (tens of microjoule), intense (>8 MV/cm), and broadband (0.01~60 THz) THz radiation in two-color laser mixing in air. Such an intense THz field can be utilized to study THz-driven extremely nonlinear phenomena in a university laboratory.

  2. Strong terahertz field generation, detection, and application

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki-Yong [Univ. of Maryland, College Park, MD (United States)

    2016-05-15

    This report describes the generation and detection of high-power, broadband terahertz (THz) radiation with using femtosecond terawatt (TW) laser systems. In particular, this focuses on two-color laser mixing in gases as a scalable THz source, addressing both microscopic and macroscopic effects governing its output THz yield and radiation profile. This also includes the characterization of extremely broad THz spectra extending from microwaves to infrared frequencies. Experimentally, my group has generated high-energy (tens of microjoule), intense (>8 MV/cm), and broadband (0.01~60 THz) THz radiation in two-color laser mixing in air. Such an intense THz field can be utilized to study THz-driven extremely nonlinear phenomena in a university laboratory.

  3. HIGH-EFFICIENCY INFRARED RECEIVER

    Directory of Open Access Journals (Sweden)

    A. K. Esman

    2016-01-01

    Full Text Available Recent research and development show promising use of high-performance solid-state receivers of the electromagnetic radiation. These receivers are based on the low-barrier Schottky diodes. The approach to the design of the receivers on the basis of delta-doped low-barrier Schottky diodes with beam leads without bias is especially actively developing because for uncooled receivers of the microwave radiation these diodes have virtually no competition. The purpose of this work is to improve the main parameters and characteristics that determine the practical relevance of the receivers of mid-infrared electromagnetic radiation at the operating room temperature by modifying the electrodes configuration of the diode and optimizing the distance between them. Proposed original design solution of the integrated receiver of mid-infrared radiation on the basis of the low-barrier Schottky diodes with beam leads allows to effectively adjust its main parameters and characteristics. Simulation of the electromagnetic characteristics of the proposed receiver by using the software package HFSS with the basic algorithm of a finite element method which implemented to calculate the behavior of electromagnetic fields on an arbitrary geometry with a predetermined material properties have shown that when the inner parts of the electrodes of the low-barrier Schottky diode is performed in the concentric elliptical convex-concave shape, it can be reduce the reflection losses to -57.75 dB and the standing wave ratio to 1.003 while increasing the directivity up to 23 at a wavelength of 6.09 μm. At this time, the rounded radii of the inner parts of the anode and cathode electrodes are equal 212 nm and 318 nm respectively and the gap setting between them is 106 nm. These parameters will improve the efficiency of the developed infrared optical-promising and electronic equipment for various purposes intended for work in the mid-infrared wavelength range. 

  4. Does a leaf absorb radiation in the near infrared (780-900 nm) region? A new approach to quantifying optical reflection, absorption and transmission of leaves.

    Science.gov (United States)

    Merzlyak, Mark N; Chivkunova, Olga B; Melø, T B; Naqvi, K Razi

    2002-01-01

    The following question is addressed here: do healthy leaves absorb, as the spectra published over the last 50 years indicate, some 5-20% of incident radiation in the 780-900 nm region? The answer is found to be negative, and previous findings result from incomplete collection of the transmitted light by the detection system (even when the leaf is placed next to, but outside, the entrance port of an integrating sphere). A simple remedy for this inherent flaw in the experimental arrangement is applied successfully to leaves (of 10 unrelated species) differing in thickness, age and pigment content. The study has shown that, from an optical standpoint, a leaf tissue is a highly scattering material, and the infinite reflectance of a leaf is exceedingly sensitive to trace amounts of absorbing components. It is shown that water contributes, in a thick leaf (Kalanchoe blossfeldiana), an easily detectable signal even in the 780-900 nm region. The practical benefits resulting from improved measurements of leaf spectra are pointed out.

  5. Using a non-invasive technique in nutrition: synchrotron radiation infrared microspectroscopy spectroscopic characterization of oil seeds treated with different processing conditions on molecular spectral factors influencing nutrient delivery.

    Science.gov (United States)

    Zhang, Xuewei; Yu, Peiqiang

    2014-07-02

    Non-invasive techniques are a key to study nutrition and structure interaction. Fourier transform infrared microspectroscopy coupled with a synchrotron radiation source (SR-IMS) is a rapid, non-invasive, and non-destructive bioanalytical technique. To understand internal structure changes in relation to nutrient availability in oil seed processing is vital to find optimal processing conditions. The objective of this study was to use a synchrotron-based bioanalytical technique SR-IMS as a non-invasive and non-destructive tool to study the effects of heat-processing methods and oil seed canola type on modeled protein structure based on spectral data within intact tissue that were randomly selected and quantify the relationship between the modeled protein structure and protein nutrient supply to ruminants. The results showed that the moisture heat-related processing significantly changed (p0.05) in the protein spectral profile between the raw and dry-heated canola tissue and between yellow- and brown-type canola tissue. The results indicated that different heat processing methods have different impacts on the protein inherent structure. The protein intrinsic structure in canola seed tissue was more sensitive and more response to the moisture heating in comparison to the dry heating. These changes are expected to be related to the nutritive value. However, the current study is based on limited samples, and more large-scale studies are needed to confirm our findings.

  6. Gluon scattering amplitudes at strong coupling

    Energy Technology Data Exchange (ETDEWEB)

    Alday, Luis F. [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands); Maldacena, Juan [School of Natural Sciences, Institute for Advanced Study, Princeton, NJ 08540 (United States)

    2007-06-15

    We describe how to compute planar gluon scattering amplitudes at strong coupling in N = 4 super Yang Mills by using the gauge/string duality. The computation boils down to finding a certain classical string configuration whose boundary conditions are determined by the gluon momenta. The results are infrared divergent. We introduce the gravity version of dimensional regularization to define finite quantities. The leading and subleading IR divergencies are characterized by two functions of the coupling that we compute at strong coupling. We compute also the full finite form for the four point amplitude and we find agreement with a recent ansatz by Bern, Dixon and Smirnov.

  7. Tm2+ luminescent materials for solar radiation conversion devices

    NARCIS (Netherlands)

    Van der Kolk, E.

    2015-01-01

    A solar radiation conversion device is described that comprises a luminescent Tm 2+ inorganic material for converting solar radiation of at least part of the UV and/or visible and/or infra red solar spectrum into infrared solar radiation, preferably said infrared solar radiation having a wavelength

  8. Thermography by Infrared

    International Nuclear Information System (INIS)

    Harara, W.; Allouch, Y.; Altahan, A.

    2015-08-01

    This study focused on the principle’s explanation of metallic components and structures testing by thermography method using infrared waves. The study confirmed that, thermal waves testing technique as one of the most important method among the modern non-destructive testing methods. It is characterized by its economy, easy to apply and timely testing of components and metallic structures. This method is applicable to a wide variety of components such as testing pieces of planes, power plants, electric transmission lines and aerospace components, in order to verify their structures and fabrication quality and their comformance to the international standards.Testing the components by thermography using infrared radiation is easy and rapid if compared to other NDT methods. The study included an introduction to the thermography testing method, its equipements, components and the applied technique. Finally, two practical applications are given in order to show the importance of this method in industry concerned with determining the liquid level in a tank and testing the stability of the control box of electrical supply.(author)

  9. Effect of simultaneous infrared dry-blanching and dehydration on quality characteristics of carrot slices

    Science.gov (United States)

    This study investigated the effects of various processing parameters on carrot slices exposed to infrared (IR) radiation heating for achieving simultaneous infrared dry-blanching and dehydration (SIRDBD). The investigated parameters were product surface temperature, slice thickness and processing ti...

  10. The relationship between the biomass of Cameroonian tropical forests and radiation reflected in middle infrared wavelengths (3.0-5.0 micro m)

    International Nuclear Information System (INIS)

    Boyd, D.S.; Foody, G.M.; Curran, P.J.

    1999-01-01

    The continued northwards spread of Rhodesian sleeping sickness or Human African Trypanosomiasis (HAT) within Uganda is raising concerns of overlap with the Gambian form of the disease. Disease convergence would result in compromised diagnosis and treatment for HAT. Spatial determinants for HAT are poorly understood across small areas. This study examines the relationships between Rhodesian HAT and several environmental, climatic and social factors in two newly affected districts, Kaberamaido and Dokolo. A one-step logistic regression analysis of HAT prevalence and a two-step logistic regression method permitted separate analysis of both HAT occurrence and HAT prevalence. Both the occurrence and prevalence of HAT were negatively correlated with distance to the closest livestock market in all models. The significance of distance to the closest livestock market strongly indicates that HAT may have been introduced to this previously unaffected area via the movement of infected, untreated livestock from endemic areas. This illustrates the importance of the animal reservoir in disease transmission, and highlights the need for trypanosomiasis control in livestock and the stringent implementation of regulations requiring the treatment of cattle prior to sale at livestock markets to prevent any further spread of Rhodesian HAT within Uganda. (author)

  11. Strongly Correlated Topological Insulators

    Science.gov (United States)

    2016-02-03

    Strongly Correlated Topological Insulators In the past year, the grant was used for work in the field of topological phases, with emphasis on finding...surface of topological insulators. In the past 3 years, we have started a new direction, that of fractional topological insulators. These are materials...in which a topologically nontrivial quasi-flat band is fractionally filled and then subject to strong interactions. The views, opinions and/or

  12. Strong Cosmic Censorship

    Science.gov (United States)

    Isenberg, James

    2017-01-01

    The Hawking-Penrose theorems tell us that solutions of Einstein's equations are generally singular, in the sense of the incompleteness of causal geodesics (the paths of physical observers). These singularities might be marked by the blowup of curvature and therefore crushing tidal forces, or by the breakdown of physical determinism. Penrose has conjectured (in his `Strong Cosmic Censorship Conjecture`) that it is generically unbounded curvature that causes singularities, rather than causal breakdown. The verification that ``AVTD behavior'' (marked by the domination of time derivatives over space derivatives) is generically present in a family of solutions has proven to be a useful tool for studying model versions of Strong Cosmic Censorship in that family. I discuss some of the history of Strong Cosmic Censorship, and then discuss what is known about AVTD behavior and Strong Cosmic Censorship in families of solutions defined by varying degrees of isometry, and discuss recent results which we believe will extend this knowledge and provide new support for Strong Cosmic Censorship. I also comment on some of the recent work on ``Weak Null Singularities'', and how this relates to Strong Cosmic Censorship.

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  14. Infrared Sky Imager (IRSI) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Victor R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-04-01

    The Infrared Sky Imager (IRSI) deployed at the Atmospheric Radiation Measurement (ARM) Climate Research Facility is a Solmirus Corp. All Sky Infrared Visible Analyzer. The IRSI is an automatic, continuously operating, digital imaging and software system designed to capture hemispheric sky images and provide time series retrievals of fractional sky cover during both the day and night. The instrument provides diurnal, radiometrically calibrated sky imagery in the mid-infrared atmospheric window and imagery in the visible wavelengths for cloud retrievals during daylight hours. The software automatically identifies cloudy and clear regions at user-defined intervals and calculates fractional sky cover, providing a real-time display of sky conditions.

  15. Introduction to experimental infrared spectroscopy fundamentals and practical methods

    CERN Document Server

    Tasumi, Mitsuo; Ochiai, Shukichi

    2014-01-01

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

  16. Strong Arcwise Connectedness

    OpenAIRE

    Espinoza, Benjamin; Gartside, Paul; Kovan-Bakan, Merve; Mamatelashvili, Ana

    2012-01-01

    A space is `n-strong arc connected' (n-sac) if for any n points in the space there is an arc in the space visiting them in order. A space is omega-strong arc connected (omega-sac) if it is n-sac for all n. We study these properties in finite graphs, regular continua, and rational continua. There are no 4-sac graphs, but there are 3-sac graphs and graphs which are 2-sac but not 3-sac. For every n there is an n-sac regular continuum, but no regular continuum is omega-sac. There is an omega-sac ...

  17. Abortion: Strong's counterexamples fail

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2009-01-01

    This paper shows that the counterexamples proposed by Strong in 2008 in the Journal of Medical Ethics to Marquis's argument against abortion fail. Strong's basic idea is that there are cases--for example, terminally ill patients--where killing an adult human being is prima facie seriously morally......'s scenarios have some valuable future or admitted that killing them is not seriously morally wrong. Finally, if "valuable future" is interpreted as referring to objective standards, one ends up with implausible and unpalatable moral claims....

  18. The infrared image simulation of the tank under different movement states

    Science.gov (United States)

    Gao, Xiang; Mu, Cheng-po; Peng, Ming-song; Dong, Qing-xian; Zhang, Rui-heng

    2017-07-01

    Tank, as a vital ground weapon, plays an irreplaceable role in the war. The article did the research of infrared image of the tank. Firstly, the 3D model of tank was established. And then the infrared radiation model of the target was constructed by analysing the infrared characteristics of the tank's different parts.. Finally the infrared radiation value of the tank under different states was calculated and the simulation of infrared characteristics of the tank under different states was done, which will provide reference for the research on infrared characteristics of the army's battlefield target.

  19. A strong comeback

    International Nuclear Information System (INIS)

    Marier, D.

    1992-01-01

    This article presents the results of a financial rankings survey which show a strong economic activity in the independent energy industry. The topics of the article include advisor turnover, overseas banks, and the increase in public offerings. The article identifies the top project finance investors for new projects and restructurings and rankings for lenders

  20. Near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Virendra Jain

    2015-01-01

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

  1. Achieving a strongly negative scattering asymmetry factor in random media composed of dual-dipolar particles

    Science.gov (United States)

    Wang, B. X.; Zhao, C. Y.

    2018-02-01

    Understanding radiative transfer in random media like micro- or nanoporous and particulate materials, allows people to manipulate the scattering and absorption of radiation, as well as opens new possibilities in applications such as imaging through turbid media, photovoltaics, and radiative cooling. A strong-backscattering phase function, i.e., a negative scattering asymmetry parameter g , is of great interest, which can possibly lead to unusual radiative transport phenomena, for instance, Anderson localization of light. Here we demonstrate that by utilizing the structural correlations and second Kerker condition for a disordered medium composed of randomly distributed silicon nanoparticles, a strongly negative scattering asymmetry factor (g ˜-0.5 ) for multiple light scattering can be realized in the near infrared. Based on the multipole expansion of Foldy-Lax equations and quasicrystalline approximation (QCA), we have rigorously derived analytical expressions for the effective propagation constant and scattering phase function for a random system containing spherical particles, by taking the effect of structural correlations into account. We show that as the concentration of scattering particles rises, the backscattering is also enhanced. Moreover, in this circumstance, the transport mean free path is largely reduced and even becomes smaller than that predicted by independent scattering approximation. We further explore the dependent scattering effects, including the modification of electric and magnetic dipole excitations and far-field interference effect, both induced and influenced by the structural correlations, for volume fraction of particles up to fv˜0.25 . Our results have profound implications in harnessing micro- or nanoscale radiative transfer through random media.

  2. Infrared imaging of the crime scene: possibilities and pitfalls.

    Science.gov (United States)

    Edelman, Gerda J; Hoveling, Richelle J M; Roos, Martin; van Leeuwen, Ton G; Aalders, Maurice C G

    2013-09-01

    All objects radiate infrared energy invisible to the human eye, which can be imaged by infrared cameras, visualizing differences in temperature and/or emissivity of objects. Infrared imaging is an emerging technique for forensic investigators. The rapid, nondestructive, and noncontact features of infrared imaging indicate its suitability for many forensic applications, ranging from the estimation of time of death to the detection of blood stains on dark backgrounds. This paper provides an overview of the principles and instrumentation involved in infrared imaging. Difficulties concerning the image interpretation due to different radiation sources and different emissivity values within a scene are addressed. Finally, reported forensic applications are reviewed and supported by practical illustrations. When introduced in forensic casework, infrared imaging can help investigators to detect, to visualize, and to identify useful evidence nondestructively. © 2013 American Academy of Forensic Sciences.

  3. Strong Electroweak Symmetry Breaking

    CERN Document Server

    Grinstein, Benjamin

    2011-01-01

    Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor,...

  4. Plasmons in strong superconductors

    International Nuclear Information System (INIS)

    Baldo, M.; Ducoin, C.

    2011-01-01

    We present a study of the possible plasmon excitations that can occur in systems where strong superconductivity is present. In these systems the plasmon energy is comparable to or smaller than the pairing gap. As a prototype of these systems we consider the proton component of Neutron Star matter just below the crust when electron screening is not taken into account. For the realistic case we consider in detail the different aspects of the elementary excitations when the proton, electron components are considered within the Random-Phase Approximation generalized to the superfluid case, while the influence of the neutron component is considered only at qualitative level. Electron screening plays a major role in modifying the proton spectrum and spectral function. At the same time the electron plasmon is strongly modified and damped by the indirect coupling with the superfluid proton component, even at moderately low values of the gap. The excitation spectrum shows the interplay of the different components and their relevance for each excitation modes. The results are relevant for neutrino physics and thermodynamical processes in neutron stars. If electron screening is neglected, the spectral properties of the proton component show some resemblance with the physical situation in high-T c superconductors, and we briefly discuss similarities and differences in this connection. In a general prospect, the results of the study emphasize the role of Coulomb interaction in strong superconductors.

  5. Transmissive infrared frequency selective surfaces and infrared antennas: final report for LDRD 105749

    International Nuclear Information System (INIS)

    Wendt, Joel Robert; Hadley, G. Ronald; Samora, Sally; Loui, Hung; Cruz-Cabrera, Alvaro Augusto; Davids, Paul; Kemme, Shanalyn A.; Basilio, Lorena I.; Johnson, William Arthur; Peters, David William

    2009-01-01

    Plasmonic structures open up new opportunities in photonic devices, sometimes offering an alternate method to perform a function and sometimes offering capabilities not possible with standard optics. In this LDRD we successfully demonstrated metal coatings on optical surfaces that do not adversely affect the transmission of those surfaces at the design frequency. This technology could be applied as an RF noise blocking layer across an optical aperture or as a method to apply an electric field to an active electro-optic device without affecting optical performance. We also demonstrated thin optical absorbers using similar patterned surfaces. These infrared optical antennas show promise as a method to improve performance in mercury cadmium telluride detectors. Furthermore, these structures could be coupled with other components to lead to direct rectification of infrared radiation. This possibility leads to a new method for infrared detection and energy harvesting of infrared radiation.

  6. Study on laser and infrared attenuation performance of carbon nanotubes

    Science.gov (United States)

    Liu, Xiang-cui; Liu, Qing-hai; Dai, Meng-yan; Cheng, Xiang; Fang, Guo-feng; Zhang, Tong; Liu, Haifeng

    2014-11-01

    In recent years, the weapon systems of laser and infrared (IR) imaging guidance have been widely used in modern warfare because of their high precision and strong anti-interference. However, military smoke, a rapid and effective passive jamming method, can effectively counteract the attack of precision-guided weapons by their scattering and absorbing effects. The traditional smoke has good visible light (0.4-0.76μm) obscurant performance, but hardly any effects to other electromagnetic wave bands while the weapon systems of laser and IR imaging guidance usually work in broad band, including the near-infrared (1-3μm), middle-infrared (3-5μm), far-infrared (8-14μm), and so on. Accordingly, exploiting new effective obscurant materials has attracted tremendous interest worldwide nowadays. As is known, the nano-structured materials have lots of unique properties comparing with the traditional materials suggesting that they might be the perfect alternatives to solve the problems above. Carbon nanotubes (CNTs) are well-ordered, all-carbon hollow graphitic nano-structured materials with a high aspect ratio, lengths from several hundred nanometers to several millimeters. CNTs possess many unique intrinsic physical-chemical properties and are investigated in many areas reported by the previous studies. However, no application research about CNTs in smoke technology field is reported yet. In this paper, the attenuation performances of CNTs smoke to laser and IR were assessed in 20m3 smoke chamber. The testing wavebands employed in experiments are 1.06μm and 10.6μm laser, 3-5μm and 8-14μm IR radiation. The main parameters were obtained included the attenuation rate, transmission rate, mass extinction coefficient, etc. The experimental results suggest that CNTs smoke exhibits excellent attenuation ability to the broadband IR radiation. Their mass extinction coefficients are all above 1m2·g-1. Nevertheless, the mass extinction coefficients vary with the sampling time

  7. Radiative cooling in the nocturnal boundary layer

    NARCIS (Netherlands)

    Tjemkes, S.A.

    1988-01-01

    In this thesis the transfer of infrared radiation (electromagnetic waves with a wavelength between 3.6 and 100 μm) through a cloudfree nocturnal boundary layer is studied. To simulate the transfer of infrared radiation an accurate narrow band model which simulates the absorption and

  8. Plasmonic Moon: a Fano-like approach for squeezing the magnetic field in the infrared

    KAUST Repository

    Panaro, Simone

    2015-08-11

    Outstanding results have been achieved in the localization of optical electric fields via ultrasmall plasmonic cavities, paving the way to the subdiffractive confinement of local electromagnetic fields. However, due to the intrinsic constraints related to conventional architectures, no comparable squeezing factors have been managed yet for the magnetic counterpart of radiation, practically hindering the detection and manipulation of magneto-optical effects at the nanoscale. Here, we observe a strong magnetic field nanofocusing in the infrared, promoted by the induction of a coil-type Fano resonance. By triggering the coil current via a quadrupole-like plasmonic mode, we straightforwardly boost the enhancement of the infrared magnetic field and perform its efficient squeezing in localized nanovolumes.

  9. High-pressure research at the SISSI infrared beamline of the elettra storage-ring

    International Nuclear Information System (INIS)

    Andrea, P.

    2016-01-01

    The SISSI infrared beamline of the Elettra storage-ring is a very valuable tool for the study of the low energy electrodynamics of materials at high pressures. Thanks to the high brightness of infrared synchrotron radiation, SISSI allows to perform reflectivity and/or transmission experiments in a Diamond Anvil Cell, from THz to visible wavelengths. This opportunity has been exploited to tackle several fundamental problems in solid-state physics, especially in the fi eld of strongly-correlated electron systems, Mott insulator to metal transitions and superconductivity. Other interesting applications range from organic semiconductors to biology and chemistry. After outlining the characteristics of the beamline and its capabilities for high-pressure research, we will review some of the most recent results from the SISSI beamline. (author)

  10. Theory of strong-field attosecond transient absorption

    International Nuclear Information System (INIS)

    Wu, Mengxi; Chen, Shaohao; Camp, Seth; Schafer, Kenneth J; Gaarde, Mette B

    2016-01-01

    Attosecond transient absorption is one of the promising new techniques being developed to exploit the availability of sub-femtosecond extreme ultraviolet (XUV) pulses to study the dynamics of the electron on its natural time scale. The temporal resolution in a transient absorption setup comes from the control of the relative delay and coherence between pump and probe pulses, while the spectral resolution comes from the characteristic width of the features that are being probed. In this review we focus on transient absorption scenarios where an attosecond pulse of XUV radiation creates a broadband excitation that is subsequently probed by a few cycle infrared (IR) laser. Because the attosecond XUV pulses are locked to the IR field cycle, the exchange of energy in the laser–matter interaction can be studied with unprecedented precision. We focus on the transient absorption by helium atoms of XUV radiation around the first ionization threshold, where we can simultaneoulsy solve the time-dependent Schrödinger equation for the single atom response and the Maxwell wave equation for the collective response of the nonlinear medium. We use a time-domain method that allows us to treat on an equal footing all the different linear and nonlinear processes by which the medium can exchange energy with the fields. We present several simple models, based on a few-level system interacting with a strong IR field, to explain many of the novel features found in attosecond transient absorption spectrograms. These include the presence of light-induced states, which demonstrate the ability to probe the dressed states of the atom. We also present a time-domain interpretation of the resonant pulse propagation features that appear in absorption spectra in dense, macroscopic media. We close by reviewing several recent experimental results that can be explained in terms of the models we discuss. Our aim is to present a road map for understanding future attosecond transient absorption

  11. <strong>Relative Biological Effect of Antiprotonsstrong>> strong>

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael

    purpose/objective The AD-4/ACE collaboration has recently performed experiments to directly measure the RBE of antiprotons. Antiprotons have very similar stopping power compared to protons, but when they come to rest, antiprotons will annihilate on a target nucleus and thereby release almost 2 Ge......V of energy. About 30 MeV of this energy is deposited in the vicinity of the Bragg-peak, thereby significantly enhancing it. It is furthermore expected that this additional energy is deposited by radiation which carries a high-LET component. This will have a significant influence on the radiobiological...... nuclear research facility CERN. A beam of 126 MeV antiprotons, corresponding to about 12 cm range in water, was spread out to a SOBP with a width of 1 cm. Dosimetry experiments were carried out with ionization chambers, alanine pellets and radiochromic film, and the results were used for benchmarking...

  12. An infrared study of the Magellanic clouds

    NARCIS (Netherlands)

    Schwering, Petrus Bernardus Wilhelmus

    1988-01-01

    The thesis describes infrared radiation and dust properties of the Magellanic Clouds, together with comparisons with emission at other wavelength regimes. Observations of the SMC and LMC were made with the IRAS satellite. Maps are presented at wavelengths of 12, 25, 60 and 100 μm. From these maps a

  13. 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…

  14. Strong-coupling approximations

    International Nuclear Information System (INIS)

    Abbott, R.B.

    1984-03-01

    Standard path-integral techniques such as instanton calculations give good answers for weak-coupling problems, but become unreliable for strong-coupling. Here we consider a method of replacing the original potential by a suitably chosen harmonic oscillator potential. Physically this is motivated by the fact that potential barriers below the level of the ground-state energy of a quantum-mechanical system have little effect. Numerically, results are good, both for quantum-mechanical problems and for massive phi 4 field theory in 1 + 1 dimensions. 9 references, 6 figures

  15. Strong interaction and QFD

    International Nuclear Information System (INIS)

    Ebata, T.

    1981-01-01

    With an assumed weak multiplet structure for bosonic hadrons, which is consistent with the ΔI = 1/2 rule, it is shown that the strong interaction effective hamiltonian is compatible with the weak SU(2) x U(1) gauge transformation. Especially the rho-meson transforms as a triplet under SU(2)sub(w), and this is the origin of the rho-photon analogy. It is also shown that the existence of the non-vanishing Cabibbo angle is a necessary condition for the absence of the exotic hadrons. (orig.)

  16. Semiconductor optoelectronic infrared spectroscopy

    International Nuclear Information System (INIS)

    Hollingworth, A.R.

    2001-08-01

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

  17. Strong Coupling Holography

    CERN Document Server

    Dvali, Gia

    2009-01-01

    We show that whenever a 4-dimensional theory with N particle species emerges as a consistent low energy description of a 3-brane embedded in an asymptotically-flat (4+d)-dimensional space, the holographic scale of high-dimensional gravity sets the strong coupling scale of the 4D theory. This connection persists in the limit in which gravity can be consistently decoupled. We demonstrate this effect for orbifold planes, as well as for the solitonic branes and string theoretic D-branes. In all cases the emergence of a 4D strong coupling scale from bulk holography is a persistent phenomenon. The effect turns out to be insensitive even to such extreme deformations of the brane action that seemingly shield 4D theory from the bulk gravity effects. A well understood example of such deformation is given by large 4D Einstein term in the 3-brane action, which is known to suppress the strength of 5D gravity at short distances and change the 5D Newton's law into the four-dimensional one. Nevertheless, we observe that the ...

  18. Introductory survey for wireless infrared communications

    Directory of Open Access Journals (Sweden)

    Munsif Ali Jatoi

    2014-08-01

    Full Text Available Wireless infrared communications can be defined as the propagation of light waves in free space using infrared radiation whose range is 400–700 nm. This range corresponds to frequencies of hundreds of terahertz, which is high for higher data rate applications. Wireless infrared is applied for higher data rates applications such as wireless computing, wireless video and wireless multimedia communication applications. Introduced by Gfeller, this field has grown with different link configurations, improved transmitter efficiency, increased receiver responsivity and various multiple access techniques for improved quality. Errors are caused because of background light, which causes degradation overall system performance. Error correction techniques are used to remove the errors caused during transmission. This study provides a brief account on field theory used for error correction in wireless infrared systems. The results are produced in terms of bit error rate and signal-to-noise ratio for various bit lengths to show the ability of encoding and decoding algorithms.

  19. Stimulated coherent transition radiation

    International Nuclear Information System (INIS)

    Hung-chi Lihn.

    1996-03-01

    Coherent radiation emitted from a relativistic electron bunch consists of wavelengths longer than or comparable to the bunch length. The intensity of this radiation out-numbers that of its incoherent counterpart, which extends to wavelengths shorter than the bunch length, by a factor equal to the number of electrons in the bunch. In typical accelerators, this factor is about 8 to 11 orders of magnitude. The spectrum of the coherent radiation is determined by the Fourier transform of the electron bunch distribution and, therefore, contains information of the bunch distribution. Coherent transition radiation emitted from subpicosecond electron bunches at the Stanford SUNSHINE facility is observed in the far-infrared regime through a room-temperature pyroelectric bolometer and characterized through the electron bunch-length study. To measure the bunch length, a new frequency-resolved subpicosecond bunch-length measuring system is developed. This system uses a far-infrared Michelson interferometer to measure the spectrum of coherent transition radiation through optical autocorrelation with resolution far better than existing time-resolved methods. Hence, the radiation spectrum and the bunch length are deduced from the autocorrelation measurement. To study the stimulation of coherent transition radiation, a special cavity named BRAICER is invented. Far-infrared light pulses of coherent transition radiation emitted from electron bunches are delayed and circulated in the cavity to coincide with subsequent incoming electron bunches. This coincidence of light pulses with electron bunches enables the light to do work on electrons, and thus stimulates more radiated energy. The possibilities of extending the bunch-length measuring system to measure the three-dimensional bunch distribution and making the BRAICER cavity a broadband, high-intensity, coherent, far-infrared light source are also discussed

  20. Effects of exhaust temperature on helicopter infrared signature

    International Nuclear Information System (INIS)

    Cheng-xiong, Pan; Jing-zhou, Zhang; Yong, Shan

    2013-01-01

    The effects of exhaust temperature on infrared signature (in 3–5 μm band) for a helicopter equipped with integrative infrared suppressor were numerically investigated. The internal flow of exhaust gas and the external downwash flow, as well as the mixing between exhaust gas and downwash were simulated by CFD software to determine the temperature distributions on the helicopter skin and in the exhaust plume. Based on the skin and plume temperature distributions, a forward–backward ray-tracing method was used to calculate the infrared radiation intensity from the helicopter with a narrow-band model. The results show that for a helicopter with its integrative infrared suppressor embedded inside its rear airframe, the exhaust temperature has significant influence on the plume radiation characteristics, while the helicopter skin radiation intensity has little impact. When the exhaust temperature is raised from 900 K to 1200 K, the plume radiation intensity in 3–5 μm band is increased by about 100%, while the skin radiation intensity is increased by only about 5%. In general, the effects of exhaust temperature on helicopter infrared radiation intensity are mainly concentrated on plume, especially obvious for a lower skin emissivity case. -- Highlights: ► The effect of exhaust temperature on infrared signature for a helicopter is numerically investigated. ► The impact of exhaust temperature on helicopter skin temperature is revealed. ► The impact of exhaust temperature on plume radiation characteristics is revealed. ► The impact of exhaust temperature on helicopter skin radiation is revealed. ► The impact of exhaust temperature on helicopter's total infrared radiation intensity is revealed

  1. Feldspar, Infrared Stimulated Luminescence

    DEFF Research Database (Denmark)

    Jain, Mayank

    2014-01-01

    This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars.......This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars....

  2. Infrared Detectors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The end goal of this project is to develop proof-of-concept infrared detectors which can be integrated in future infrared instruments engaged in remote...

  3. LIGO: The strong belief

    CERN Multimedia

    Antonella Del Rosso

    2016-01-01

    Twenty years of designing, building and testing a number of innovative technologies, with the strong belief that the endeavour would lead to a historic breakthrough. The Bulletin publishes an abstract of the Courier’s interview with Barry Barish, one of the founding fathers of LIGO.   The plots show the signals of gravitational waves detected by the twin LIGO observatories at Livingston, Louisiana, and Hanford, Washington. (Image: Caltech/MIT/LIGO Lab) On 11 February, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo collaborations published a historic paper in which they showed a gravitational signal emitted by the merger of two black holes. These results come after 20 years of hard work by a large collaboration of scientists operating the two LIGO observatories in the US. Barry Barish, Linde Professor of Physics, Emeritus at the California Institute of Technology and former Director of the Global Design Effort for the Internat...

  4. Extragalactic infrared astronomy

    International Nuclear Information System (INIS)

    Gondhalekar, P.M.

    1985-05-01

    The paper concerns the field of Extragalactic Infrared Astronomy, discussed at the Fourth RAL Workshop on Astronomy and Astrophysics. Fifteen papers were presented on infrared emission from extragalactic objects. Both ground-(and aircraft-) based and IRAS infrared data were reviewed. The topics covered star formation in galaxies, active galactic nuclei and cosmology. (U.K.)

  5. Infrared thermography; Thermographie infrarouge

    Energy Technology Data Exchange (ETDEWEB)

    Chrysochoos, A.; Wattrisse, B. [Montpellier-2 Univ., Lab. de Mecanique et Genie Civil, UMR 5508 CNRS (France); Feldheim, V.; Lybaert, P. [Faculte Polytechnique de Mons, Service de Thermique et Combustion, Mons (Belgium); Batsale, J.Ch.; Mourand, D. [Trefle, UMR 8508, Cellule Thermicar, UMR 8508, 33 - Talence (France)

    2005-07-01

    This session about infrared thermography gathers 3 articles dealing with: the use of thermo-mechanical measurement fields for the characterization of materials behaviour; the application of infrared thermography to the study of convective transfers; and some data processing methods for the characterization of fields of thermophysical properties of materials or for the infrared thermography analysis of thermal processes. (J.S.)

  6. Passive radiative cooling design with broadband optical thin-film filters

    Science.gov (United States)

    Kecebas, Muhammed Ali; Menguc, M. Pinar; Kosar, Ali; Sendur, Kursat

    2017-09-01

    The operation of most electronic semiconductor devices suffers from the self-generated heat. In the case of photovoltaic or thermos-photovoltaic cells, their exposure to sun or high temperature sources make them get warm beyond the desired operating conditions. In both incidences, the solution strategy requires effective radiative cooling process, i.e., by selective absorption and emission in predetermined spectral windows. In this study, we outline two approaches for alternative 2D thin film coatings, which can enhance the passive thermal management for application to electronic equipment. Most traditional techniques use a metallic (silver) layer because of their high reflectivity, although they display strong absorption in the visible and near-infrared spectrums. We show that strong absorption in the visible and near-infrared spectrums due to a metallic layer can be avoided by repetitive high index-low index periodic layers and broadband reflection in visible and near-infrared spectrums can still be achieved. These modifications increase the average reflectance in the visible and near-infrared spectrums by 3-4%, which increases the cooling power by at least 35 W/m2. We also show that the performance of radiative cooling can be enhanced by inserting an Al2O3 film (which has strong absorption in the 8-13 μm spectrum, and does not absorb in the visible and near-infrared) within conventional coating structures. These two approaches enhance the cooling power of passive radiative cooling systems from the typical reported values of 40 W/m2-100 W/m2 and 65 W/m2 levels respectively.

  7. 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

  8. John Strong (1941 - 2006)

    CERN Multimedia

    Wickens, F

    Our friend and colleague John Strong was cruelly taken from us by a brain tumour on Monday 31st July, a few days before his 65th birthday John started his career working with a group from Westfield College, under the leadership of Ted Bellamy. He obtained his PhD and spent the early part of his career on experiments at Rutherford Appleton Laboratory (RAL), but after the early 1970s his research was focussed on experiments in CERN. Over the years he made a number of notable contributions to experiments in CERN: The Omega spectrometer adopted a system John had originally developed for experiments at RAL using vidicon cameras to record the sparks in the spark chambers; He contributed to the success of NA1 and NA7, where he became heavily involved in the electronic trigger systems; He was responsible for the second level trigger system for the ALEPH detector and spent five years leading a team that designed and built the system, which ran for twelve years with only minor interventions. Following ALEPH he tur...

  9. Adaptive infrared-reflecting systems inspired by cephalopods

    Science.gov (United States)

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

    2018-03-01

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

  10. Radiation safety at CERN

    International Nuclear Information System (INIS)

    Hoefert, M.

    1995-09-01

    CERN, the European Laboratory for Particle Physics, operates proton accelerators up to an energy of 450 GeV and an electron-positron storage ring in the 50 GeV energy range for fundamental high-energy particle physics. A strong radiation protection group assures the radiation safety of these machines both during their operation and in periods of maintenance and repair. Particular radiation problems in an accelerator laboratory are presented and recent developments in radiation protection at CERN discussed. (author)

  11. Electromagnetic emission of a strongly charged oscillating droplet

    Science.gov (United States)

    Grigor'ev, A. I.; Kolbneva, N. Yu.; Shiryaeva, S. O.

    2016-08-01

    Analytical expressions for electric field in the vicinity of an oscillating strongly charged droplet of nonviscous conducting liquid and intensity of electromagnetic radiation are derived in the linear approximation with respect to perturbation amplitude of the droplet surface. Order-of-magnitude estimations of the radiation intensity are presented. The intensity of electromagnetic radiation of a ball lightning that can be simulated using a charged droplet is not related to the surface oscillations.

  12. Synthesis and characterization of CuO nanoparticles using strong ...

    Indian Academy of Sciences (India)

    Synthesis and characterization of CuO nanoparticles using strong base electrolyte ... Fourier transform infrared spectrum showed that the CuO ..... Hydrogen bub- bles play a key role in generation of sparks and metal removal in the electrochemical discharge process. Flower-like morphology could be attained with both the.

  13. HPV16 DNA status is a strong prognosticator of loco-regional control after postoperative radiochemotherapy of locally advanced oropharyngeal carcinoma: results from a multicentre explorative study of the German Cancer Consortium Radiation Oncology Group (DKTK-ROG).

    Science.gov (United States)

    Lohaus, Fabian; Linge, Annett; Tinhofer, Inge; Budach, Volker; Gkika, Eleni; Stuschke, Martin; Balermpas, Panagiotis; Rödel, Claus; Avlar, Melanie; Grosu, Anca-Ligia; Abdollahi, Amir; Debus, Jürgen; Bayer, Christine; Belka, Claus; Pigorsch, Steffi; Combs, Stephanie E; Mönnich, David; Zips, Daniel; von Neubeck, Cläre; Baretton, Gustavo B; Löck, Steffen; Thames, Howard D; Krause, Mechthild; Baumann, Michael

    2014-12-01

    To investigate the impact of HPV status in patients with locally advanced head and neck squamous cell carcinoma (HNSCC), who received surgery and cisplatin-based postoperative radiochemotherapy. For 221 patients with locally advanced squamous cell carcinoma of the hypopharynx, oropharynx or oral cavity treated at the 8 partner sites of the German Cancer Consortium, the impact of HPV DNA, p16 overexpression and p53 expression on outcome were retrospectively analysed. The primary endpoint was loco-regional tumour control; secondary endpoints were distant metastases and overall survival. In the total patient population, univariate analyses revealed a significant impact of HPV16 DNA positivity, p16 overexpression, p53 positivity and tumour site on loco-regional tumour control. Multivariate analysis stratified for tumour site showed that positive HPV 16 DNA status correlated with loco-regional tumour control in patients with oropharyngeal carcinoma (p=0.02) but not in the oral cavity carcinoma group. Multivariate evaluation of the secondary endpoints in the total population revealed a significant association of HPV16 DNA positivity with overall survival (p<0.01) but not with distant metastases. HPV16 DNA status appears to be a strong prognosticator of loco-regional tumour control after postoperative cisplatin-based radiochemotherapy of locally advanced oropharyngeal carcinoma and is now being explored in a prospective validation trial. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. High efficiency quasi-monochromatic infrared emitter

    Energy Technology Data Exchange (ETDEWEB)

    Brucoli, Giovanni; Besbes, Mondher; Benisty, Henri, E-mail: henri.benisty@institutoptique.fr; Greffet, Jean-Jacques [Laboratoire Charles Fabry, UMR 8501, Institut d’Optique, CNRS, Université Paris-Sud 11, 2, Avenue Augustin Fresnel, 91127 Palaiseau Cedex (France); Bouchon, Patrick; Haïdar, Riad [Office National d’Études et de Recherches Aérospatiales, Chemin de la Hunière, 91761 Palaiseau (France)

    2014-02-24

    Incandescent radiation sources are widely used as mid-infrared emitters owing to the lack of alternative for compact and low cost sources. A drawback of miniature hot systems such as membranes is their low efficiency, e.g., for battery powered systems. For targeted narrow-band applications such as gas spectroscopy, the efficiency is even lower. In this paper, we introduce design rules valid for very generic membranes demonstrating that their energy efficiency for use as incandescent infrared sources can be increased by two orders of magnitude.

  15. Infrared drying of herbs (Research Note

    Directory of Open Access Journals (Sweden)

    K. PÄÄKKÖNEN

    2008-12-01

    Full Text Available Drying experiments on peppermint (Mentha piperita L., anise hyssop (Agastache foeniculum L., parsley (Petroselinum crispum L. and garden angelica (Angelica archangelica L. were conducted using near infrared drying, operating at a product temperature of 35-50°C. The oil content, composition and residual water content of the dried herbs were determined. The microbiological quality of the fresh and the dried material was determined for total bacterial count and coliforms, moulds and yeasts. The results indicate that infrared radiation is has potential for drying herbs since it is gentle and shortens the processing time.

  16. Small business innovation program. Phase 1: Selective thermal radiators

    Science.gov (United States)

    Hauer, C. R.

    1980-05-01

    Experiments used ion implantation to modify the radiation and evaporation surface properties of tungsten filaments operating at about 2800 K. Tungsten filaments ion implanted with carbon at low energy showed an ability to dissipate more energy than unimplanted tungsten filaments when operated in parallel prior to filament failure. Infrared reflectance measurements of a blackbody source indicated anomolous behavior, in that the reflectance and emittance of the surface appeared to be a strong function of the wavelength in the vicinity of the period. There appeared to be a concomitant shift toward longer wavelengths in the peak of the reflected blackbody radiance spectrum when a periodically structured reflector was used.

  17. Pixel-level plasmonic microcavity infrared photodetector

    Science.gov (United States)

    Jing, You Liang; Li, Zhi Feng; Li, Qian; Chen, Xiao Shuang; Chen, Ping Ping; Wang, Han; Li, Meng Yao; Li, Ning; Lu, Wei

    2016-05-01

    Recently, plasmonics has been central to the manipulation of photons on the subwavelength scale, and superior infrared imagers have opened novel applications in many fields. Here, we demonstrate the first pixel-level plasmonic microcavity infrared photodetector with a single quantum well integrated between metal patches and a reflection layer. Greater than one order of magnitude enhancement of the peak responsivity has been observed. The significant improvement originates from the highly confined optical mode in the cavity, leading to a strong coupling between photons and the quantum well, resulting in the enhanced photo-electric conversion process. Such strong coupling from the localized surface plasmon mode inside the cavity is independent of incident angles, offering a unique solution to high-performance focal plane array devices. This demonstration paves the way for important infrared optoelectronic devices for sensing and imaging.

  18. The Far Infrared Earth

    Science.gov (United States)

    Harries, John; Carli, Bruno; Rizzi, Rolando; Serio, Carmine; Mlynczak, Martin G.; Palchetti, Luca; Maestri, T.; Brindley, H.; Masiello, Guido

    2007-01-01

    The paper presents a review of the far infrared (FIR) properties of the Earth's atmosphere, and the role of these properties in climate. These properties have been relatively poorly understood, and it is one of the purposes of this review to demonstrate that, in recent years, we have made great strides in improving this understanding. Seen from space, the Earth is a cool object, with an effective emitting temperature of about 255 K. This contrasts with a global mean surface temperature of 288 K, and is due primarily to strong absorption of outgoing longwave energy by water vapour, carbon dioxide and clouds (especially ice). A large fraction of this absorption occurs in the FIR, and so the Earth is effectively a FIR planet. The FIR is important in a number of key climate processes, for example the water vapour and cloud feedbacks (especially ice clouds). The FIR is also a spectral region which can be used to remotely sense and retrieve atmospheric composition in the presence of ice clouds. Recent developments in instrumentation have allowed progress in each of these areas, which are described, and proposals for a spaceborne FIR instrument are being formulated. It is timely to review the FIR properties of the clear and cloudy atmosphere, the role of FIR processes in climate, and its use in observing our planet from space.

  19. Application of infrared technique in research of mechanical properties

    International Nuclear Information System (INIS)

    Huang, Y.; Shih, C.H.

    1985-08-01

    The infrared technique as a new method is more useful for research of materials science. This paper simply describes the techniques of infrared temperature measurement and thermography and provides the experimental data of some metals and alloys during the deformation and the fatigue process by use of the infrared sensing method. It is shown that the conventional tensile data can be correlated with infrared radiational energy change during the tensile pulling. The temperature field of metal during elastic-plastic deformation can be calculated by finite element analysis, and the thermoelastic effect of metal can be shown by thermography. The infrared technique can be used to predict the fatigue damage, monitor their propagations and give the alarm at fracture. Finally, it must be pointed out that the irreversibility of infrared emission of metal can be used as a basis of nondestructive testing. (author)

  20. Effects of plume afterburning on infrared spectroscopy

    Science.gov (United States)

    Zhu, Xijuan; Xu, Ying; Ma, Jing; Duan, Ran; Wu, Jie

    2017-10-01

    Contains H2, CO and unburned components of high-temperature plume of rocket engine, then injected into the atmosphere, continue to carry out the oxidation reaction in the plume near field region with the volume in the plume of oxygen in the air, two times burning. The afterburning is an important cause of infrared radiation intensification of propellant plume, which increases the temperature of the flame and changes the components of the gas, thus enhancing the infrared radiation intensity of the flame. [1]. Two the combustion numerical using chemical reaction mechanism involving HO2 intermediate reaction, the study confirmed that HO2 is a key intermediate, plays a decisive role to trigger early response, on afterburning temperature and flow concentration distribution effect. A finite rate chemical reaction model is used to describe the two burning phenomenon in high temperature plume[2]. In this paper, a numerical simulation of the flame flow field and radiative transfer is carried out for the afterburning phenomenon. The effects of afterburning on the composition, temperature and infrared radiation of the plume are obtained by comparison.

  1. Application of infra-red techniques to research on mechanical properties

    OpenAIRE

    Huang, Y.; Shih, C.H.

    2013-01-01

    Infra-red techniques can serve as a new tool, particularly useful in materials science research work. This paper describes the available techniques for infra-red temperature measurement and thermography, and provides experimental data for some metals and alloys, obtained by infra-red sensing during deformation and fatigue processes. It is shown that conventional tensile data can be correlated with the change in infra-red radiation which occurs during tensile stressing. The temperature field o...

  2. Shaded Spacecraft Radiators to Be Used on the Daytime Surface of the Mercury Planet, the Moon, and Asteroids of the Solar System Inner Part

    Directory of Open Access Journals (Sweden)

    V. A. Igrickii

    2016-01-01

    Full Text Available During the daytime a surface of the Moon, Mercury planet, and asteroids of the Solar system inner part, significantly heats up, and infrared radiation of the local soil becomes essential. At the same time direct solar radiation and reflected from the surface solar radiation reach the maximum too. These radiation fluxes can significantly decrease the efficiency of spacecraft radiators in the daytime. This effect is especially strong on the Mercury surface where direct solar radiation is 10 times stronger than solar radiation near the Earth. As a result, on the daytime surface of the Mercury the conventional low-temperature radiators become completely disabled.The article describes the development of the special shaded spacecraft radiators to be used in daytime on the Mercury and other atmosphereless bodies of the Solar system inner part. To solve this task are used mirror shades. The shape of these shades is developed to improve operation conditions of the spacecraft radiator through the appropriate scheme of radiation reflection. The task is discussed in 2D and 3D cases. A new design of shaded spacecraft radiators is proposed, and reasonable proportions of radiators are determined. The performance capability of proposed radiators for environments of the Mercury and the Moon is estimated using the zonal method in view of partial mirror reflection. The calculations showed that the developed shaded spacecraft radiators are capable to work on the Mercury surface as the low-temperature radiators even during the daytime. New radiators provide minimum accepted operating temperature of 241К (-32°С, meanwhile radiators of common design have minimum operating temperature of 479К (206°С. Using such radiators on the Moon enables us to increase effectiveness of spacecraft radiators and to decrease their minimum operating temperature from 270К (-3°С to 137К (-136°С.

  3. [Cool/Hot target effect of the water fog infrared stealth].

    Science.gov (United States)

    Du, Yong-cheng; Yang, Li; Zhang, Shi-cheng; Yang, Zhen; Hu, Shuang-xi

    2012-08-01

    Artificial spray fog will come into being cool target because of the strong evaporation and convection but weak radiation heat flux, when it is used for defence of infrared imaging guided missile. Also, when it is the contrary condition, the water fog will come into being hot target. In order to open out the phenomenon particularly, a math model which can account for the cool/hot effect produced by water fog shielding the thermal radiation is established by coupling the calculation of radiation transfer equation and energy conversation equation, based on the Mie theory. This model is proved to be accurate in comparison with the Monte-Carlo method and Lambert-Beer' law. The water fog is seemed as absorbing, emitting and anisotropic scattering medium, and the medium radiation, multiple scattering, target radiation flux, and environment influence such as the conductivity, convection turbulent heat diffusion and evaporation is calculated. The phenomenon of cool/hot target effect can be shown in detail with this model.

  4. Radiation protection and the safety of radiation sources

    International Nuclear Information System (INIS)

    1996-01-01

    These Safety Fundamentals cover the protection of human beings against ionizing radiation (gamma and X rays and alpha, beta and other particles that can induce ionization as they interact with biological materials), referred to herein subsequently as radiation, and the safety of sources that produce ionizing radiation. The Fundamentals do not apply to non-ionizing radiation such as microwave, ultraviolet, visible and infrared radiation. They do not apply either to the control of non-radiological aspects of health and safety. They are, however, part of the overall framework of health and safety

  5. Optical radiation in modern medicine

    OpenAIRE

    Sowa, Pawe?; Rutkowska-Talipska, Joanna; Rutkowski, Krzysztof; Koszty?a-Hojna, Bo?ena; Rutkowski, Ryszard

    2013-01-01

    Optical radiation extends between microwaves and X-rays of the electromagnetic radiation and includes ultraviolet (UV), visible light (VL) and infrared (IR) components. The dose of radiation that reaches the skin is influenced by the ozone layer, position of the Sun, latitude, altitude, cloud cover and ground reflections. The photobiological effects of UV, VL and IR bands depend on their wavelength, frequency and mechanism of action. They are modified by the thickness, structure, vasculature ...

  6. Mid-Infrared Lasers

    Data.gov (United States)

    National Aeronautics and Space Administration — Mid infrared solid state lasers for Differential Absorption Lidar (DIAL) systems required for understanding atmospheric chemistry are not available. This program...

  7. Electromagnetic radiation from a laser wakefield accelerator

    NARCIS (Netherlands)

    Khachatryan, A.G.; van Goor, F.A.; Boller, Klaus J.

    2008-01-01

    Coherent and incoherent electromagnetic radiation emitted from a laser wakefield accelerator is calculated based on Lienard-Wiechert potentials. It is found that at wavelengths longer than the bunch length, the radiation is coherent. The coherent radiation, which typically lies in the infrared

  8. A model to calculate solar radiation fluxes on the Martian surface

    Directory of Open Access Journals (Sweden)

    Vicente-Retortillo Álvaro

    2015-01-01

    Full Text Available We present a new comprehensive radiative transfer model to study the solar irradiance that reaches the surface of Mars in the spectral range covered by MetSIS, a sensor aboard the Mars MetNet mission that will measure solar irradiance in several bands from the ultraviolet (UV to the near infrared (NIR. The model includes up-to-date wavelength-dependent radiative properties of dust, water ice clouds, and gas molecules. It enables the characterization of the radiative environment in different spectral regions under different scenarios. Comparisons between the model results and MetSIS observations will allow for the characterization of the temporal variability of atmospheric optical depth and dust size distribution, enhancing the scientific return of the mission. The radiative environment at the Martian surface has important implications for the habitability of Mars as well as a strong impact on its atmospheric dynamics and climate.

  9. Infrared thermal imaging in connective tissue diseases.

    Science.gov (United States)

    Chojnowski, Marek

    2017-01-01

    Infrared thermal imaging (IRT) is a non-invasive, non-contact technique which allows one to measure and visualize infrared radiation. In medicine, thermal imaging has been used for more than 50 years in various clinical settings, including Raynaud's phenomenon and systemic sclerosis. Imaging and quantification of surface body temperature provides an indirect measure of the microcirculation's overall performance. As such, IRT is capable of confirming the diagnosis of Raynaud's phenomenon, and, with additional cold or heat challenge, of differentiating between the primary and secondary condition. In systemic sclerosis IRT has a potential role in assessing disease activity and monitoring treatment response. Despite certain limitations, thermal imaging can find a place in clinical practice, and with the introduction of small, low-cost infrared cameras, possibly become a part of routine rheumatological evaluation.

  10. Teaching physics and understanding infrared thermal imaging

    Science.gov (United States)

    Vollmer, Michael; Möllmann, Klaus-Peter

    2017-08-01

    Infrared thermal imaging is a very rapidly evolving field. The latest trends are small smartphone IR camera accessories, making infrared imaging a widespread and well-known consumer product. Applications range from medical diagnosis methods via building inspections and industrial predictive maintenance etc. also to visualization in the natural sciences. Infrared cameras do allow qualitative imaging and visualization but also quantitative measurements of the surface temperatures of objects. On the one hand, they are a particularly suitable tool to teach optics and radiation physics and many selected topics in different fields of physics, on the other hand there is an increasing need of engineers and physicists who understand these complex state of the art photonics systems. Therefore students must also learn and understand the physics underlying these systems.

  11. Prediction of multiple resonance characteristics by an extended resistor-inductor-capacitor circuit model for plasmonic metamaterials absorbers in infrared.

    Science.gov (United States)

    Xu, Xiaolun; Li, Yongqian; Wang, Binbin; Zhou, Zili

    2015-10-01

    The resonance characteristics of plasmonic metamaterials absorbers (PMAs) are strongly dependent on geometric parameters. A resistor-inductor-capacitor (RLC) circuit model has been extended to predict the resonance wavelengths and the bandwidths of multiple magnetic polaritons modes in PMAs. For a typical metallic-dielectric-metallic structure absorber working in the infrared region, the developed model describes the correlation between the resonance characteristics and the dimensional sizes. In particular, the RLC model is suitable for not only the fundamental resonance mode, but also for the second- and third-order resonance modes. The prediction of the resonance characteristics agrees fairly well with those calculated by the finite-difference time-domain simulation and the experimental results. The developed RLC model enables the facilitation of designing multi-band PMAs for infrared radiation detectors and thermal emitters.

  12. Spherical warm shield design for infrared imaging systems

    Science.gov (United States)

    Tian, Qijie; Chang, Songtao; He, Fengyun; Li, Zhou; Qiao, Yanfeng

    2017-09-01

    The F-number matching is the primary means to suppress stray radiation for infrared imaging systems. However, it is difficult to achieve exact F-number matching, owing to the restriction from detectors, or multiple F-number design. Hence, an additional shield is required to block the certain thermal radiation. Typical shield is called flat warm shield, which is flat and operates at room temperature. For flat warm shield, it cannot suppress stray radiation while achieving F-number matching. To overcome the restriction, a spherical reflective warm shield is required. First of all, the detailed theory of spherical warm shield design is developed on basis of the principle that stray radiation cannot directly reach the infrared focal plane array. According to the theory developed above, a polished spherical warm shield, whose radius is 18 mm, is designed to match an F/2 infrared detector with an F/4 infrared imaging system. Then, the performance and alignment errors of the designed spherical warm shield are analyzed by simulation. Finally, a contrast experiment between the designed spherical warm shield and two differently processed flat warm shields is performed in a chamber with controllable inside temperatures. The experimental results indicate that the designed spherical warm shield cannot only achieve F-number matching but suppress stray radiation sufficiently. Besides, it is demonstrated that the theory of spherical warm shield design developed in this paper is valid and can be employed by arbitrary infrared imaging systems.

  13. Multispectral infrared imaging interferometer

    Science.gov (United States)

    Potter, A. E., Jr.

    1971-01-01

    Device permitting simultaneous viewing of infrared images at different wavelengths consists of imaging lens, Michelson interferometer, array of infrared detectors, data processing equipment for Fourier transformation of detector signal, and image display unit. Invention is useful in earth resources applications, nondestructive testing, and medical diagnoses.

  14. Photoionization Modeling of Infrared Fine-Structure Lines in Luminous Galaxies with Central Dust-Bounded Nebulae

    National Research Council Canada - National Science Library

    Fischer, Jacqueline; Allen, Robert; Dudley, C. C; Satyapal, Shobita; Luhman, Michael L; Wolfire, Mark G; Smith, Howard A

    2001-01-01

    Far-infrared spectroscopy of a small sample of IR-bright galaxies taken with the Infrared Space Observatory Long Wavelength Spectrometer has revealed a dramatic progression extending from strong fine...

  15. Airplane radiation dose decrease during a strong Forbush decrease

    Czech Academy of Sciences Publication Activity Database

    Spurný, František; Kudela, K.; Dachev, T.

    2004-01-01

    Roč. 2, S05001 (2004), s. 1-4 ISSN 1542-7390 Grant - others:EC project(XE) FIGM-CT2000-00068 Institutional research plan: CEZ:AV0Z1048901 Keywords : airplane dose * Forbush decrease * cosmic rays Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders

  16. Accurate, practical simulation of satellite infrared radiometer spectral data

    International Nuclear Information System (INIS)

    Sullivan, T.J.

    1982-09-01

    This study's purpose is to determine whether a relatively simple random band model formulation of atmospheric radiation transfer in the infrared region can provide valid simulations of narrow interval satellite-borne infrared sounder system data. Detailed ozonesondes provide the pertinent atmospheric information and sets of calibrated satellite measurements provide the validation. High resolution line-by-line model calculations are included to complete the evaluation

  17. Ground squirrels use an infrared signal to deter rattlesnake predation

    OpenAIRE

    Rundus, Aaron S.; Owings, Donald H.; Joshi, Sanjay S.; Chinn, Erin; Giannini, Nicolas

    2007-01-01

    The evolution of communicative signals involves a major hurdle; signals need to effectively stimulate the sensory systems of their targets. Therefore, sensory specializations of target animals are important sources of selection on signal structure. Here we report the discovery of an animal signal that uses a previously unknown communicative modality, infrared radiation or “radiant heat,” which capitalizes on the infrared sensory capabilities of the signal's target. California ground squirrels...

  18. DNA Infrared Absorbency Detection using Photopyroelectric Technique and FTIR Spectroscopy

    OpenAIRE

    Ebu-TEİR, Musa; Abu-TAHA, Mohammad; Al-JAMAL, Atef; EİDEH, H.

    2008-01-01

    Absorbencies of different DNA samples were studied using the well known photopyroelectric (PPE) technique and Fourier Transform Infrared (FTIR) spectrometer. In the fi rst method, wideband radiation absorbance from an infrared (IR) pulsed wideband source (PWBS) by DNA samples were detected and compared with FTIR spectrum. It was shown that the PPE technique results are useful and comparable to FTIR in distinguishing different DNA samples of biological interests

  19. 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...

  20. Infrared and optical properties of the emission-line galaxies NGC 1386 and NGC 1365

    International Nuclear Information System (INIS)

    Phillips, M.M.; Frogel, J.A.

    1980-01-01

    We have obtained optical spectrophotometry and broad-band infrared data for the nucleus of the emission-line galaxy NGC 1386. These observations are discussed and compared with our own optical spectrophotometry as well as published optical and infrared measurements of the nucleus of the neighboring ''hot spot'' galaxy NGC 1365. Both galaxies show large infared excesses. The very high excitation emission-line spectrum of NGC 1386 is that of a type of 2 Seyfert, making this galaxy the closest known member of this class of objects. We find direct evidence for a significant early-type stellar population in the nucleus of NGC 1365, thus strengthening the previous conclusion that the nuclear emission lines of this galaxy are excited by the radiation of young, hot stars. In addition, we confirm the presence of weak [Ne V] and He II emission, which suggests that a nonthermal source of ionization may also be present. The nucleus of NGC 1365 is emitting a factor of 10 more energy in both the optical emission lines and the infrared than is that of NGC 1386. Finally, we point out the uncertainty in identification of NGC 1365 as an X-ray source in view of its proximity of a Seyfert 2, galaxy, several of which have now been shown to be strong X-ray emitters

  1. Application of visible and infrared spectroscopy for the evaluation of evolved glauconite

    Science.gov (United States)

    Chattoraj, Shovan L.; Banerjee, Santanu; van der Meer, Freek; Champati Ray, P. K.

    2018-02-01

    The Oligocene Maniyara Fort Formation in western India exhibits two distinct glauconite types with different maturation states, which are characterized by their spectral response in the visible to infrared spectrum of electromagnetic radiation. Spectral signatures of Maniyara Fort glauconites display absorption features at approximately 0.77, 1.08, 1.9, 2.3 μm in the visible-short-wave infrared (SWIR) and 2.8 and 10 μm in the mid-infrared (MIR) region which vary with K2O content of glauconite. The spectra of glauconite varies significantly as a function of its cationic contents and substitution in different sites. The maturity is found to increase in tandem with the metal-metal charge transfer (CT) and the Fe2+ dd absorption band respectively at 1.08 and 0.77 μm. H2O and OH- signatures at the NIR region reflect differences in the sensitivity of glauconites with different molecular H2O content. In the MIR region, a gradual shift of the Sisbnd O stretch at 10 μm towards lower wavelengths indicates the dominance of smectite layers in glauconites. This study demonstrates a strong correlation between the proportion of expandable layers in the glauconite structure with variations in characteristic band position, depth and symmetry in reflectance and emissivity.

  2. Electrodynamics of a hydrogenlike atom in a strong electromagnetic field

    International Nuclear Information System (INIS)

    Kovarskij, V.A.; Perel'man, N.F.

    1974-01-01

    The quasienergy spectrum of the hydrogen atom in strong electromagnetic radiation is studied, the luminescence of the atom under these conditions is considered. It is shown that in a strong field the atom, being even in the ground state, radiates a spectrum of frequencies corresponding to transitions from the ground state into excited states, the strong field photons being involved. The intensity of such a luminescence is basically a non-linear function of the strong field. The exposure of the atom to two strong electromagnetic fields Ω and ω (Ω>>ω) is considered, the Ω coinciding with one of the natural frquencies of the atom. The effct of modulation of the resonance shift for an atomic level by the ω-field strength is predicted. The dependence of Ω-absorption in the ω-field on the statistic properties of the latter is investigated. (author)

  3. Infrared gas heating applied to industrial processes; Le chauffage infrarouge au gaz applique aux procedes industriels

    Energy Technology Data Exchange (ETDEWEB)

    Goodhue, C. [Gaz Metropolitain, Montreal, PQ (Canada)

    1996-03-01

    The theory of radiative heat transfer and the concepts of emissive power and coupled emitters and receptors were presented. Different types of radiative infrared gas heaters available for industrial applications were also reviewed. These include perforated ceramic plate heaters, fibrous panels, combined radiative and convective ceramic heaters, radiative tubes and catalytic panels. The respective advantages of these different heaters were discussed. Application domains of infrared radiative gas heaters include drying in the pulp and paper and textile industries, various drying and baking needs in the agro-food industry, and other applications in the plastic and paint industries. 3 figs.

  4. Charms of radiation research

    International Nuclear Information System (INIS)

    Inokuti, M.

    2005-01-01

    Most of my professional efforts over nearly five decades have been devoted to radiation research, that is, studies of the physical, chemical, and biological actions of high-energy radiation on matter. (By the term 'high-energy radiation' I mean here x rays, .GAMMA. rays, neutrons, and charged particles of high enough energies to produce ionization in matter. I exclude visible light, infrared waves, microwaves, and sound waves.) Charms of radiation research lie in its interdisciplinary character; although my training was in basic physics, the scope of my interest has gradually increased to cover many other areas, to my deep satisfaction. High-energy radiation is an important component of the universe, and of our environment. It often provides an effective avenue for characterizing matter and understanding its behavior. Near Earth's surface this radiation is normally present in exceptionally low quantity, and yet it plays a significant role in some atmospheric phenomena such as auroras, and also in the evolution of life. The recent advent of various devices for producing high-energy radiation has opened up the possibility of many applications, including medical and industrial uses. I have worked on some aspects of those uses. At every opportunity to address a broad audience I try to convey a sense of intellectual fun, together with some of the elements of the basic science involved. A goal of radiation education might be to make the word 'radiation' as common and familiar as words such as 'fire' and 'electricity' through increased usage

  5. Charms of radiation research

    International Nuclear Information System (INIS)

    Inokuti, Mitio

    2005-01-01

    Most of my professional efforts over nearly five decades have been devoted to radiation research, that is, studies of the physical, chemical, and biological actions of high-energy radiation on matter. (By the term high-energy radiation'' I mean here x rays, γ rays, neutrons, and charged particles of high enough energies to produce ionization in manner. I exclude visible light, infrared waves, microwaves, and sound waves.) Charms of radiation research lie in its interdisciplinary character, although my training was in basic physics, the scope of my interest has gradually increased to cover many other areas, to my deep satisfaction. High-energy radiation is an important component of the universe, and of our environment. It often provides an effective avenue for characterizing matter and understanding its behavior. Near Earth's surface this radiation is normally present in exceptionally low quantity, and yet it plays a significant role in some atmospheric phenomena such as auroras, and also in the evolution of life. The recent advent of various devices for producing high-energy radiation has opened up the possibility of many applications, including medical and industrial uses. I have worked on some aspects of those uses. At every opportunity to address a broad audience I try to convey a sense of intellectual fun, together with some of the elements of the basic science involved. A goal of radiation education might be to make the word radiation'' as common and familiar as words such as ''fire'' and electricity'' through increased usage. (author)

  6. Helical magnetized wiggler for synchrotron radiation laser

    CERN Document Server

    Wang Mei; Hirshfield, J L

    1999-01-01

    A helical magnetized iron wiggler has been built for a novel infrared synchrotron radiation laser (SRL) experiment. The wiggler consists of four periods of helical iron structure immersed in a solenoid field. This wiggler is to impart transverse velocity to a prebunched 6 MeV electron beam, and thus to obtain a desired high orbit pitch ratio for the SRL. Field tapering at beam entrance is considered and tested on a similar wiggler. Analytic and simulated characteristics of wigglers of this type are discussed and the performance of the fabricated wigglers is demonstrated experimentally. A 4.7 kG peak field was measured for a 6.4 mm air gap and a 5.4 cm wiggler period at a 20 kG solenoid field. The measured helical fields compare favorably with the analytical solution. This type of helical iron wigglers has the potential to be scaled to small periods with strong field amplitude.

  7. Helical magnetized wiggler for synchrotron radiation laser

    International Nuclear Information System (INIS)

    Wang Mei; Park, S.Y.; Hirshfield, J.L.

    1999-01-01

    A helical magnetized iron wiggler has been built for a novel infrared synchrotron radiation laser (SRL) experiment. The wiggler consists of four periods of helical iron structure immersed in a solenoid field. This wiggler is to impart transverse velocity to a prebunched 6 MeV electron beam, and thus to obtain a desired high orbit pitch ratio for the SRL. Field tapering at beam entrance is considered and tested on a similar wiggler. Analytic and simulated characteristics of wigglers of this type are discussed and the performance of the fabricated wigglers is demonstrated experimentally. A 4.7 kG peak field was measured for a 6.4 mm air gap and a 5.4 cm wiggler period at a 20 kG solenoid field. The measured helical fields compare favorably with the analytical solution. This type of helical iron wigglers has the potential to be scaled to small periods with strong field amplitude

  8. Hybrid infrared scene projector (HIRSP): a high dynamic range infrared scene projector, part II

    Science.gov (United States)

    Cantey, Thomas M.; Bowden, Mark; Cosby, David; Ballard, Gary

    2008-04-01

    This paper is a continuation of the merging of two dynamic infrared scene projector technologies to provide a unique and innovative solution for the simulation of high dynamic temperature ranges for testing infrared imaging sensors. This paper will present some of the challenges and performance issues encountered in implementing this unique projector system into a Hardware-in-the-Loop (HWIL) simulation facility. The projection system combines the technologies of a Honeywell BRITE II extended voltage range emissive resistor array device and an optically scanned laser diode array projector (LDAP). The high apparent temperature simulations are produced from the luminescent infrared radiation emitted by the high power laser diodes. The hybrid infrared projector system is being integrated into an existing HWIL simulation facility and is used to provide real-world high radiance imagery to an imaging infrared unit under test. The performance and operation of the projector is presented demonstrating the merit and success of the hybrid approach. The high dynamic range capability simulates a 250 Kelvin apparent background temperature to 850 Kelvin maximum apparent temperature signatures. This is a large increase in radiance projection over current infrared scene projection capabilities.

  9. Wireless intelligent alarm technology with pyroelectric infrared sensor

    Science.gov (United States)

    Chen, Xiao

    2009-07-01

    Aiming at the defects of monitoring conducted by man in the conventional practice, we study the passive intelligent automatic alarm technology based on the pyroelectric infrared sensor and wireless communication technology. The designed passive infrared wireless alarm is composed of pyroelectric infrared sensors, infrared special chip BISS0001 and their peripheral circuits. When someone enters into the detecting and monitoring range, the alarm will detect the infrared ray of the human radiation by the contactless form and detect the signals of circuit output. Then it translates them into low frequency signals relative with human sports speed, distance and direction, produce corresponding output signals through amplifying by the back state controller, switch on the work power of the wireless transmitting circuit and make it emit the alarm signals. The system enhances the monitoring level and effects and possesses many advantages such as wide detecting range, long detecting distance and high reliability.

  10. Infrared thermography for temperature measurement and non-destructive testing.

    Science.gov (United States)

    Usamentiaga, Rubén; Venegas, Pablo; Guerediaga, Jon; Vega, Laura; Molleda, Julio; Bulnes, Francisco G

    2014-07-10

    The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed.

  11. Infrared Thermography for Temperature Measurement and Non-Destructive Testing

    Science.gov (United States)

    Usamentiaga, Rubèn; Venegas, Pablo; Guerediaga, Jon; Vega, Laura; Molleda, Julio; Bulnes, Francisco G.

    2014-01-01

    The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed. PMID:25014096

  12. Infrared Thermography for Temperature Measurement and Non-Destructive Testing

    Directory of Open Access Journals (Sweden)

    Rubén Usamentiaga

    2014-07-01

    Full Text Available The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed.

  13. Ultra-thin infrared metamaterial detector for multicolor imaging applications.

    Science.gov (United States)

    Montoya, John A; Tian, Zhao-Bing; Krishna, Sanjay; Padilla, Willie J

    2017-09-18

    The next generation of infrared imaging systems requires control of fundamental electromagnetic processes - absorption, polarization, spectral bandwidth - at the pixel level to acquire desirable information about the environment with low system latency. Metamaterial absorbers have sparked interest in the infrared imaging community for their ability to enhance absorption of incoming radiation with color, polarization and/or phase information. However, most metamaterial-based sensors fail to focus incoming radiation into the active region of a ultra-thin detecting element, thus achieving poor detection metrics. Here our multifunctional metamaterial absorber is directly integrated with a novel mid-wave infrared (MWIR) and long-wave infrared (LWIR) detector with an ultra-thin (~λ/15) InAs/GaSb Type-II superlattice (T2SL) interband cascade detector. The deep sub-wavelength metamaterial detector architecture proposed and demonstrated here, thus significantly improves the detection quantum efficiency (QE) and absorption of incoming radiation in a regime typically dominated by Fabry-Perot etalons. Our work evinces the ability of multifunctional metamaterials to realize efficient wavelength selective detection across the infrared spectrum for enhanced multispectral infrared imaging applications.

  14. SYNCHROTRON RADIATION SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    HULBERT,S.L.; WILLIAMS,G.P.

    1998-07-01

    Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

  15. Quantum electrodynamics of strong fields

    International Nuclear Information System (INIS)

    Greiner, W.

    1983-01-01

    Quantum Electrodynamics of Strong Fields provides a broad survey of the theoretical and experimental work accomplished, presenting papers by a group of international researchers who have made significant contributions to this developing area. Exploring the quantum theory of strong fields, the volume focuses on the phase transition to a charged vacuum in strong electric fields. The contributors also discuss such related topics as QED at short distances, precision tests of QED, nonperturbative QCD and confinement, pion condensation, and strong gravitational fields In addition, the volume features a historical paper on the roots of quantum field theory in the history of quantum physics by noted researcher Friedrich Hund

  16. Interpretation of thermal infrared data: The heat capacity mapping mission

    Energy Technology Data Exchange (ETDEWEB)

    Price, J.

    1985-01-01

    This book describes the measurement and analysis of global infrared radiation. Topics considered include remote sensing in the thermal infrared, regional-scale estimates of surface moisture availability and thermal inertia using remote thermal measurements, the influenced geography on local environment as inferred from night thermal infrared imagery, surface temperature as an indicator of evapotransipration and soil, association among surface temperatures sensed by satellite and agriculturally related variables, the role of remotely sensed data in studies of the thermal bar, and HCMM satellite data calibration and atmospheric corrections.

  17. Electron beam instrumentation techniques using coherent radiation

    International Nuclear Information System (INIS)

    Wang, D.X.

    1997-01-01

    Much progress has been made on coherent radiation research since coherent synchrotron radiation was first observed in 1989. The use of coherent radiation as a bunch length diagnostic tool has been studied by several groups. In this paper, brief introductions to coherent radiation and far-infrared measurement are given, the progress and status of their beam diagnostic application are reviewed, different techniques are described, and their advantages and limitations are discussed

  18. Spatial and Temporal Variabilities of Solar and Longwave Radiation Fluxes below a Coniferous Forest in the French Alps

    Science.gov (United States)

    Sicart, J. E.; Ramseyer, V.; Lejeune, Y.; Essery, R.; Webster, C.; Rutter, N.

    2017-12-01

    At high altitudes and latitudes, snow has a large influence on hydrological processes. Large fractions of these regions are covered by forests, which have a strong influence on snow accumulation and melting processes. Trees absorb a large part of the incoming shortwave radiation and this heat load is mostly dissipated as longwave radiation. Trees shelter the snow surface from wind, so sub-canopy snowmelt depends mainly on the radiative fluxes: vegetation attenuates the transmission of shortwave radiation but enhances longwave irradiance to the surface. An array of 13 pyranometers and 11 pyrgeometers was deployed on the snow surface below a coniferous forest at the CEN-MeteoFrance Col de Porte station in the French Alps (1325 m asl) during the 2017 winter in order to investigate spatial and temporal variabilities of solar and infrared irradiances in different meteorological conditions. Sky view factors measured with hemispherical photographs at each radiometer location were in a narrow range from 0.2 to 0.3. The temperature of the vegetation was measured with IR thermocouples and an IR camera. In clear sky conditions, the attenuation of solar radiation by the canopy reached 96% and its spatial variability exceeded 100 W m-2. Longwave irradiance varied by 30 W m-2 from dense canopy to gap areas. In overcast conditions, the spatial variabilities of solar and infrared irradiances were reduced and remained closely related to the sky view factor. A simple radiative model taking into account the penetration through the canopy of the direct and diffuse solar radiation, and isotropic infrared emission of the vegetation as a blackbody emitter, accurately reproduced the dynamics of the radiation fluxes at the snow surface. Model results show that solar transmissivity of the canopy in overcast conditions is an excellent proxy of the sky view factor and the emitting temperature of the vegetation remained close to the air temperature in this typically dense Alpine forest.

  19. Systems engineering and analysis of electro-optical and infrared systems

    CERN Document Server

    Arrasmith, William Wolfgang

    2015-01-01

    Introduction to Electro-optic and Infrared (EO/IR) Systems Engineering?Radiation in the Visible and Infrared Parts of the Electromagnetic SpectrumRadiation SourcesThe Effect of the Atmosphere on Optical PropagationBasic OpticsOptical ModulationThe Detection of Optical RadiationNoise in the Optical Detection ProcessTechnical Performance Measures and Metrics of Optical DetectorsModern Detectors and their Measures of PerformanceThe Effects of Cooling on Optical Detector NoiseSignal and Image ProcessingElectro-Optic and Infrared Systems AnalysisLaser Imaging Systems?Spectral Imaging?LIDAR and LADA

  20. Barrier Infrared Detector (BIRD)

    Data.gov (United States)

    National Aeronautics and Space Administration — A recent breakthrough in MWIR detector design, has resulted in a high operating temperature (HOT) barrier infrared detector (BIRD) that is capable of spectral...

  1. Infrared Sky Surveys

    Science.gov (United States)

    Price, Stephan D.

    2009-02-01

    A retrospective is given on infrared sky surveys from Thomas Edison’s proposal in the late 1870s to IRAS, the first sensitive mid- to far-infrared all-sky survey, and the mid-1990s experiments that filled in the IRAS deficiencies. The emerging technology for space-based surveys is highlighted, as is the prominent role the US Defense Department, particularly the Air Force, played in developing and applying detector and cryogenic sensor advances to early mid-infrared probe-rocket and satellite-based surveys. This technology was transitioned to the infrared astronomical community in relatively short order and was essential to the success of IRAS, COBE and ISO. Mention is made of several of the little known early observational programs that were superseded by more successful efforts.

  2. Additive Manufacturing Infrared Inspection

    Science.gov (United States)

    Gaddy, Darrell; Nettles, Mindy

    2015-01-01

    The Additive Manufacturing Infrared Inspection Task started the development of a real-time dimensional inspection technique and digital quality record for the additive manufacturing process using infrared camera imaging and processing techniques. This project will benefit additive manufacturing by providing real-time inspection of internal geometry that is not currently possible and reduce the time and cost of additive manufactured parts with automated real-time dimensional inspections which deletes post-production inspections.

  3. Assessing noise sources at synchrotron infrared ports

    International Nuclear Information System (INIS)

    Lerch, Ph.; Dumas, P.; Schilcher, T.; Nadji, A.; Luedeke, A.; Hubert, N.; Cassinari, L.; Boege, M.; Denard, J.-C.; Stingelin, L.; Nadolski, L.; Garvey, T.; Albert, S.; Gough, Ch.; Quack, M.; Wambach, J.; Dehler, M.; Filhol, J.-M.

    2012-01-01

    Low-frequency noise present in the electron and photon beams of two comparable storage rings, SOLEIL and SLS, are carefully compared in the context of IR spectroscopy using the Fourier transform technique. Today, the vast majority of electron storage rings delivering synchrotron radiation for general user operation offer a dedicated infrared port. There is growing interest expressed by various scientific communities to exploit the mid-IR emission in microspectroscopy, as well as the far infrared (also called THz) range for spectroscopy. Compared with a thermal (laboratory-based source), IR synchrotron radiation sources offer enhanced brilliance of about two to three orders of magnitude in the mid-IR energy range, and enhanced flux and brilliance in the far-IR energy range. Synchrotron radiation also has a unique combination of a broad wavelength band together with a well defined time structure. Thermal sources (globar, mercury filament) have excellent stability. Because the sampling rate of a typical IR Fourier-transform spectroscopy experiment is in the kHz range (depending on the bandwidth of the detector), instabilities of various origins present in synchrotron radiation sources play a crucial role. Noise recordings at two different IR ports located at the Swiss Light Source and SOLEIL (France), under conditions relevant to real experiments, are discussed. The lowest electron beam fluctuations detectable in IR spectra have been quantified and are shown to be much smaller than what is routinely recorded by beam-position monitors

  4. Strong WW Interaction at LHC

    Energy Technology Data Exchange (ETDEWEB)

    Pelaez, Jose R

    1998-12-14

    We present a brief pedagogical introduction to the Effective Electroweak Chiral Lagrangians, which provide a model independent description of the WW interactions in the strong regime. When it is complemented with some unitarization or a dispersive approach, this formalism allows the study of the general strong scenario expected at the LHC, including resonances.

  5. Strong-back safety latch

    International Nuclear Information System (INIS)

    DeSantis, G.N.

    1995-01-01

    The calculation decides the integrity of the safety latch that will hold the strong-back to the pump during lifting. The safety latch will be welded to the strong-back and will latch to a 1.5-in. dia cantilever rod welded to the pump baseplate. The static and dynamic analysis shows that the safety latch will hold the strong-back to the pump if the friction clamps fail and the pump become free from the strong-back. Thus, the safety latch will meet the requirements of the Lifting and Rigging Manual for under the hook lifting for static loading; it can withstand shock loads from the strong-back falling 0.25 inch

  6. Strong-back safety latch

    Energy Technology Data Exchange (ETDEWEB)

    DeSantis, G.N.

    1995-03-06

    The calculation decides the integrity of the safety latch that will hold the strong-back to the pump during lifting. The safety latch will be welded to the strong-back and will latch to a 1.5-in. dia cantilever rod welded to the pump baseplate. The static and dynamic analysis shows that the safety latch will hold the strong-back to the pump if the friction clamps fail and the pump become free from the strong-back. Thus, the safety latch will meet the requirements of the Lifting and Rigging Manual for under the hook lifting for static loading; it can withstand shock loads from the strong-back falling 0.25 inch.

  7. Hyperluminous Infrared Galaxies: The QSO-2's

    Science.gov (United States)

    Hines, D. C.

    1998-12-01

    QSO-like nuclei have been detected in the most luminous infrared galaxies known, and in many other ultraluminous infrared galaxies with ``warm'' far-IR colors. These misdirected QSOs are revealed by the morphology and spectrum of light polarized by scattering. In particular, P09104+4109 and F15307+3252 exhibit spectacular bipolar morphology in WFPC2 and NICMOS images, and broad, polarized emission-lines in their polarized spectra. This strongly suggests that the QSO nuclei are surrounded by dusty tori which obscure our direct view, but allow nuclear emission to escape through the open poles to be subsequently scattered (thus polarized) into our line of sight. Even though the radio-infrared correlation indicates ongoing star formation, if viewed from the vantage point of the scattering material, these objects would be indistinguishable from typical luminous QSOs. Hence, they should be classified as ``QSO-2's.'' These results imply that: QSO activity is intimately related to the ultraluminous infrared galaxy phenomenon. A significant fraction of the total luminosity can be generated by the non-stellar central engines. QSOs may contribute significantly to the cosmic infrared background.

  8. Infrared: A Key Technology for Security Systems

    Directory of Open Access Journals (Sweden)

    Carlo Corsi

    2012-01-01

    Full Text Available Infrared science and technology has been, since the first applications, mainly dedicated to security and surveillance especially in military field, besides specialized techniques in thermal imaging for medical diagnostic and building structures and recently in energy savings and aerospace context. Till recently the security applications were mainly based on thermal imaging as surveillance and warning military systems. In all these applications the advent of room temperature, more reliable due to the coolers avoidance, low cost, and, overall, completely integrable with Silicon technology FPAs, especially designed and tailored for specific applications, smart sensors, has really been impacted with revolutionary and new ideas and system concepts in all the infrared fields, especially for security applications. Lastly, the advent of reliable Infrared Solid State Laser Sources, operating up to the Long Infrared Wavelength Band and the new emerging techniques in Far Infrared Submillimeter Terahertz Bands, has opened wide and new areas for developing new, advanced security systems. A review of all the items with evidence of the weak and the strong points of each item, especially considering possible future developments, will be reported and discussed.

  9. Submonolayer Quantum Dot Infrared Photodetector

    Science.gov (United States)

    Ting, David Z.; Bandara, Sumith V.; Gunapala, Sarath D.; Chang, Yia-Chang

    2010-01-01

    A method has been developed for inserting submonolayer (SML) quantum dots (QDs) or SML QD stacks, instead of conventional Stranski-Krastanov (S-K) QDs, into the active region of intersubband photodetectors. A typical configuration would be InAs SML QDs embedded in thin layers of GaAs, surrounded by AlGaAs barriers. Here, the GaAs and the AlGaAs have nearly the same lattice constant, while InAs has a larger lattice constant. In QD infrared photodetector, the important quantization directions are in the plane perpendicular to the normal incidence radiation. In-plane quantization is what enables the absorption of normal incidence radiation. The height of the S-K QD controls the positions of the quantized energy levels, but is not critically important to the desired normal incidence absorption properties. The SML QD or SML QD stack configurations give more control of the structure grown, retains normal incidence absorption properties, and decreases the strain build-up to allow thicker active layers for higher quantum efficiency.

  10. Observed perturbations of the Earth's Radiation Budget - A response to the El Chichon stratospheric aerosol layer?

    Science.gov (United States)

    Ardanuy, P. E.; Kyle, H. L.

    1986-01-01

    The Earth Radiation Budget experiment, launched aboard the Nimbus-7 polar-orbiting spacecraft in late 1978, has now taken over seven years of measurements. The dataset, which is global in coverage, consists of the individual components of the earth's radiation budget, including longwave emission, net radiation, and both total and near-infrared albedos. Starting some six months after the 1982 eruption of the El Chichon volcano, substantial long-lived positive shortwave irradiance anomalies were observed by the experiment in both the northern and southern polar regions. Analysis of the morphology of this phenomena indicates that the cause is the global stratospheric aerosol layer which formed from the cloud of volcanic effluents. There was little change in the emitted longwave in the polar regions. At the north pole the largest anomaly was in the near-infrared, but at the south pole the near UV-visible anomaly was larger. Assuming an exponential decay, the time constant for the north polar, near-infrared anomaly was 1.2 years. At mid- and low latitudes the effect of the El Chichon aerosol layer could not be separated from the strong reflected-shortwave and emitted-longwave perturbations issuing from the El Nino/Southern Oscillation event of 1982-83.

  11. Renormalization in theories with strong vector forces

    International Nuclear Information System (INIS)

    Kocic, A.

    1991-01-01

    There are not many field theories in four dimensions that have sensible ultraviolet and interesting (non-trivial) infrared behavior. At present, asymptotically free theories seem to have deserved their legitimacy and there is a strong prejudice that they might be the only ones to have such a distinction. This belief stems mostly from the fact that most of the knowledge of field theory in four dimensions comes from perturbation theory. However, nonperturbative studies of the lower dimensional theories reveal a host of interesting phenomena that are perturbative studies of the lower dimensional theories reveal a host of interesting phenomena that perturbatively inaccessible. The lack of asymptotic freedom implies that the coupling constant grows at short distances and perturbation theory breaks down. Thus, in such theories, ultraviolet behavior requires nonperturbative treatment. Recently, the interest in strongly coupled gauge theories has been revived. In particularly, four dimensional quantum electrodynamics has received considerable attention. This was motivated by the discovery of an ultraviolet stable fixed point at strong couplings. If this fixed point would turn out to be non-gaussian, then QED would be the first nontrivial nonasymptotically free theory in four dimensions. The importance of such a result would be twofold. First, the old question of the existence of QED could be settled. Of course, this would be the case provided that the low energy limit of the theory actually describes photons and electrons; apriori, there is no reason to assume this. Second, the discovery of a nontrivial nonasymptotically free theory would be of great paradigmatic value. The theories which quenched QED resembles the most are nonabelian gauge theories with many flavors with beta-function positive or vanishing at weak couplings. These theories are at present considered as viable candidates for technicolor unification schemes

  12. The synchrotron radiation

    International Nuclear Information System (INIS)

    Chevallier, P.

    1994-01-01

    Synchrotron Radiation is a fantastic source of electromagnetic radiation the energy spectrum of which spreads continuously from the far infrared to hard X-rays. For this reason a wide part of the scientific community, fundamentalists as well as industry, is concerned by its use. We shall describe here the main properties of this light source and give two examples of application in the field of characterization of materials: EXAFS (Extended X-Ray Absorption Fine Structure) and X-ray fluorescence. (author). 8 figs., 21 refs

  13. Exposure assessment of aluminum arc welding radiation.

    Science.gov (United States)

    Peng, Chiung-yu; Lan, Cheng-hang; Juang, Yow-jer; Tsao, Ta-ho; Dai, Yu-tung; Liu, Hung-hsin; Chen, Chiou-jong

    2007-10-01

    The purpose of this study is to evaluate the non-ionizing radiation (NIR) exposure, especially optical radiation levels, and potential health hazard from aluminum arc welding processes based on the American Conference of Governmental Industrial Hygienists (ACGIH) method. The irradiance from the optical radiation emissions can be calculated with various biological effective parameters [i.e., S(lambda), B(lambda), R(lambda)] for NIR hazard assessments. The aluminum arc welding processing scatters bright light with NIR emission including ultraviolet radiation (UVR), visible, and infrared spectra. The UVR effective irradiance (Eeff) has a mean value of 1,100 microW cm at 100 cm distance from the arc spot. The maximum allowance time (tmax) is 2.79 s according to the ACGIH guideline. Blue-light hazard effective irradiance (EBlue) has a mean value of 1840 microW cm (300-700 nm) at 100 cm with a tmax of 5.45 s exposure allowance. Retinal thermal hazard effective calculation shows mean values of 320 mW cm(-2) sr(-1) and 25.4 mW (cm-2) (380-875 nm) for LRetina (spectral radiance) and ERetina (spectral irradiance), respectively. From this study, the NIR measurement from welding optical radiation emissions has been established to evaluate separate types of hazards to the eye and skin simultaneously. The NIR exposure assessment can be applied to other optical emissions from industrial sources. The data from welding assessment strongly suggest employees involved in aluminum welding processing must be fitted with appropriate personal protection devices such as masks and gloves to prevent serious injuries of the skin and eyes upon intense optical exposure.

  14. Titanium: light, strong, and white

    Science.gov (United States)

    Woodruff, Laurel; Bedinger, George

    2013-01-01

    Titanium (Ti) is a strong silver-gray metal that is highly resistant to corrosion and is chemically inert. It is as strong as steel but 45 percent lighter, and it is twice as strong as aluminum but only 60 percent heavier. Titanium dioxide (TiO2) has a very high refractive index, which means that it has high light-scattering ability. As a result, TiO2 imparts whiteness, opacity, and brightness to many products. ...Because of the unique physical properties of titanium metal and the whiteness provided by TiO2, titanium is now used widely in modern industrial societies.

  15. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  16. 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.

  17. Far-infrared Beamline at the Canadian Light Source

    Science.gov (United States)

    Zhao, Jianbao; Billinghurst, Brant

    2017-06-01

    Far-infrared is a particularly useful technique for studies on lattice modes as they generally appear in the Far-infrared region. Far-infrared is also an important tool for gathering information on the electrical transport properties of metallic materials and the band gap of semiconductors. This poster will describe the horizontal microscope that has recently been built in the Far-infrared beamline at the Canadian Light Source Inc. (CLS). This microscope is specially designed for high-pressure Far-infrared absorbance and reflectance spectroscopic studies. The numerical aperture (0.5) and the long working distance (82.1 mm) in the microscope are good fits for Diamond Anvil Cell (DAC). The spectra are recorded using liquid helium cooled Si bolometer or Ge:Cu detector. The pressure in the DAC can be determined by using the fluorescence spectrometer available onsite. The Far-infrared beamline at CLS is a state-of-the-art synchrotron facility, offering significantly more brightness than conventional sources. Because of the high brightness of the synchrotron radiation, we can obtain the Far-infrared reflectance/absorbance spectra on the small samples with more throughput than with a conventional source. The Far-infrared beamline is open to users through peer review.

  18. Infrared emission of a freestanding plasmonic membrane

    Science.gov (United States)

    Monshat, Hosein; Liu, Longju; McClelland, John; Biswas, Rana; Lu, Meng

    2018-01-01

    This paper reports a free-standing plasmonic membrane as a thermal emitter in the near- and mid-infrared regions. The plasmonic membrane consists of an ultrathin gold film perforated with a two-dimensional array of holes. The device was fabricated using an imprint and transfer process and fixed on a low-emissivity metal grid. The thermal radiation characteristics of the plasmonic membrane can be engineered by controlling the array period and the thickness of the gold membrane. Plasmonic membranes with two different periods were designed using electromagnetic simulation and then characterized for their transmission and infrared radiation properties. The free-standing membranes exhibit extraordinary optical transmissions with the resonant transmission coefficient as high as 76.8%. After integration with a customized heater, the membranes demonstrate narrowband thermal emission in the wavelength range of 2.5 μm to 5.5 μm. The emission signatures, including peak emission wavelength and bandwidth, are associated with the membrane geometry. The ultrathin membrane infrared emitter can be adopted in applications, such as chemical analysis and thermal imaging.

  19. Strong CP, flavor, and twisted split fermions

    International Nuclear Information System (INIS)

    Harnik, Roni; Perez, Gilad; Schwartz, Matthew D.; Shirman, Yuri

    2005-01-01

    We present a natural solution to the strong CP problem in the context of split fermions. By assuming CP is spontaneously broken in the bulk, a weak CKM phase is created in the standard model due to a twisting in flavor space of the bulk fermion wavefunctions. But the strong CP phase remains zero, being essentially protected by parity in the bulk and CP on the branes. As always in models of spontaneous CP breaking, radiative corrections to theta bar from the standard model are tiny, but even higher dimension operators are not that dangerous. The twisting phenomenon was recently shown to be generic, and not to interfere with the way that split fermions naturally weaves small numbers into the standard model. It follows that out approach to strong CP is compatible with flavor, and we sketch a comprehensive model. We also look at deconstructed version of this setup which provides a viable 4D model of spontaneous CP breaking which is not in the Nelson-Barr class. (author)

  20. Infrared imaging - A validation technique for computational fluid dynamics codes used in STOVL applications

    Science.gov (United States)

    Hardman, R. R.; Mahan, J. R.; Smith, M. H.; Gelhausen, P. A.; Van Dalsem, W. R.

    1991-01-01

    The need for a validation technique for computational fluid dynamics (CFD) codes in STOVL applications has led to research efforts to apply infrared thermal imaging techniques to visualize gaseous flow fields. Specifically, a heated, free-jet test facility was constructed. The gaseous flow field of the jet exhaust was characterized using an infrared imaging technique in the 2 to 5.6 micron wavelength band as well as conventional pitot tube and thermocouple methods. These infrared images are compared to computer-generated images using the equations of radiative exchange based on the temperature distribution in the jet exhaust measured with the thermocouple traverses. Temperature and velocity measurement techniques, infrared imaging, and the computer model of the infrared imaging technique are presented and discussed. From the study, it is concluded that infrared imaging techniques coupled with the radiative exchange equations applied to CFD models are a valid method to qualitatively verify CFD codes used in STOVL applications.

  1. An infrared and optical analysis of a sample of XBONGs and optically elusive AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K. L.; Mushotzky, R. F. [Department of Astronomy, University of Maryland, College Park, MD (United States); Koss, M., E-mail: klsmith@astro.umd.edu, E-mail: richard@astro.umd.edu, E-mail: mike.koss@phys.ethz.ch [Institute for Astronomy, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland)

    2014-10-20

    We present near-infrared (NIR) spectra of four optically elusive active galactic nuclei (AGNs) and four X-ray bright, optically normal galaxies (XBONGs) from the Swift-BAT survey. With archival observations from the Sloan Digital Sky Survey, the Two Micron All Sky Survey, Spitzer, and the Wide-field Infrared Survey Explorer (WISE), we test a number of AGN indicators in the NIR and mid-infrared; namely, NIR emission line diagnostic ratios, the presence of coronal high-ionization lines, and infrared photometry. Of our eight hard X-ray selected AGNs, we find that optical normalcy has a variety of causes from object to object, and no one explanation applies. Our objects have normal Eddington ratios and so are unlikely to host radiatively inefficient accretion flows. It is unlikely that star formation in the host or starlight dilution is contributing to their failure of optical diagnostics, except perhaps in two cases. The NIR continua are well fit by two blackbodies: one at the stellar temperature, and a hot dust component near the dust sublimation temperature. The XBONGs are more likely to have significant hot dust components, while these components are small relative to starlight in the optically elusive AGN. Some of our sample have NIR line ratios typical of AGNs, but NIR diagnostics are unsuccessful in distinguishing H II regions from AGNs in general. In one object, we discover a hidden broad-line region in the NIR. These results have strong relevance to the origin of optically normal AGNs in deep X-ray surveys.

  2. Solar cycle variability of nonmigrating tides in the infrared cooling of the thermosphere

    Science.gov (United States)

    Nischal, N.; Oberheide, J.; Mlynczak, M. G.; Marsh, D. R.

    2017-12-01

    Nitric Oxide (NO) at 5.3 μm and Carbon dioxide (CO2) at 15 μm are the major infrared emissions responsible for the radiative cooling of the thermosphere. We study the impact of two important diurnal nonmigrating tides, the DE2 and DE3, on NO and CO2 infrared emissions over a complete solar cycle (2002-2013) by (i) analyzing NO and CO2 cooling rate data from SABER and (ii) photochemical modeling using dynamical tides from a thermospheric empirical tidal model, CTMT. Both observed and modeled results show that the NO cooling rate amplitudes for DE2 and DE3 exhibit strong solar cycle dependence. NO 5.3 μm cooling rate tides are relatively unimportant for the infrared energy budget during solar minimum but important during solar maximum. On the other hand DE2 and DE3 in CO2 show comparatively small variability over a solar cycle. CO2 15 μm cooling rate tides remain, to a large extent, constant between solar minimum and maximum. This different responses by NO and CO2 emissions to the DE2 and DE3 during a solar cycle comes form the fact that the collisional reaction rate for NO is highly sensitive to the temperature comparative to that for CO2. Moreover, the solar cycle variability of these nonmigrating tides in thermospheric infrared emissions shows a clear QBO signals substantiating the impact of tropospheric weather system on the energy budget of the thermosphere. The relative contribution from the individual tidal drivers; temperature, density and advection to the observed DE2 and DE3 tides does not vary much over the course of the solar cycle, and this is true for both NO and CO2 emissions.

  3. Radiation enteritis

    Science.gov (United States)

    Radiation enteropathy; Radiation-induced small bowel injury; Post-radiation enteritis ... Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells. The therapy ...

  4. Nimbus-2 Level 2 Medium Resolution Infrared Radiometer (MRIR) V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nimbus II Medium Resolution Infrared Radiometer (MRIR) was designed to measure electromagnetic radiation emitted and reflected from the earth and its atmosphere...

  5. VO1/VO2 MARS INFRARED THERMAL MAPPER RESAMPLED DATA V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the Infrared Thermal Mapping (IRTM) data of Mars acquired by the Viking orbiters. The database contains the time, geometry, and radiative...

  6. The origin of infrared emission from the nucleus of NGC 1068

    International Nuclear Information System (INIS)

    Jones, T.W.; Stein, W.A.

    1975-01-01

    Recent infrared observational results for the nucleus of the Seyfert galaxy NGC 1068 are reviewed and analyzed in terms consistent with information available at other wavelengths. It is concluded that the infrared and optical data imply that approximately-greater-than85 percent of the infrared emission at 10μ is radiation from dust grains in the nucleus. Observed reddening of spectral lines implies geometrical optical depths at visual wavelengths approx.7--15 if the nuclear dust cloud is approximately spherically symmetric. The dust grains emitting the infrared radiation could be silicates with a 10-μ optical depth near unity, but this identification is not uniquely established. The grains are heated radiatively by an underlying source or sources of radiation also responsible for ionizing the emission-line-producing gas. The underlying source could be nonthermal, or it could be a hot plasma. Physical constraints on each of these models are derived

  7. Infrared source test

    Energy Technology Data Exchange (ETDEWEB)

    Ott, L.

    1994-11-15

    The purpose of the Infrared Source Test (IRST) is to demonstrate the ability to track a ground target with an infrared sensor from an airplane. The system is being developed within the Advance Technology Program`s Theater Missile Defense/Unmanned Aerial Vehicle (UAV) section. The IRST payload consists of an Amber Radiance 1 infrared camera system, a computer, a gimbaled mirror, and a hard disk. The processor is a custom R3000 CPU board made by Risq Modular Systems, Inc. for LLNL. The board has ethernet, SCSI, parallel I/O, and serial ports, a DMA channel, a video (frame buffer) interface, and eight MBytes of main memory. The real-time operating system VxWorks has been ported to the processor. The application code is written in C on a host SUN 4 UNIX workstation. The IRST is the result of a combined effort by physicists, electrical and mechanical engineers, and computer scientists.

  8. Mid-infrared emission and Raman spectra analysis of Er(3+)-doped oxyfluorotellurite glasses.

    Science.gov (United States)

    Chen, Fangze; Xu, Shaoqiong; Wei, Tao; Wang, Fengchao; Cai, Muzhi; Tian, Ying; Xu, Shiqing

    2015-04-10

    This paper reports on the spectroscopic and structural properties in Er(3+)-doped oxyfluorotellurite glasses. The compositional variation accounts for the evolutions of Raman spectra, Judd-Ofelt parameters, radiative properties, and fluorescent emission. It is found that, when maximum phonon energy changes slightly, phonon density plays a crucial role in quenching the 2.7 μm emission generated by the Er(3+):(4)I11/2→(4)I13/2 transition. The comparative low phonon density contributes strong 2.7 μm emission intensity. The high branching ratio (18.63%) and large emission cross section (0.95×10(-20)  cm(2)) demonstrate that oxyfluorotellurite glass contained with 50 mol.% TeO2 has potential application in the mid-infrared region laser.

  9. Low-temperature optical characterization of a near-infrared single-photon emitter in nanodiamonds

    Energy Technology Data Exchange (ETDEWEB)

    Siyushev, P; Jacques, V; Kaiser, F; Jelezko, F; Wrachtrup, J [3.Physikalisches Institut, Universitaet Stuttgart, D-70550 Stuttgart (Germany); Aharonovich, I; Castelletto, S; Prawer, S [School of Physics, University of Melbourne, VA 3010 (Australia); Mueller, T; Lombez, L; Atatuere, M [Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom)], E-mail: v.jacques@physik.uni-stuttgart.de

    2009-11-15

    In this paper, we study the optical properties of single defects emitting in the near infrared (NIR) in nanodiamonds at liquid helium temperature. The nanodiamonds are synthesized using a microwave chemical vapor deposition method followed by nickel implantation and annealing. We show that single defects exhibit several striking features at cryogenic temperature: the photoluminescence is strongly concentrated into a sharp zero-phonon line (ZPL) in the NIR, the radiative lifetime is in the nanosecond range and the emission is linearly polarized. The spectral stability of the defects is then investigated. An optical resonance linewidth of 4 GHz is measured using resonant excitation on the ZPL. Although Fourier-transform-limited emission is not achieved, our results show that it might be possible to use consecutive photons emitted in the NIR by single defects in diamond nanocrystals to perform two photon interference experiments, which are at the heart of linear quantum computing protocols.

  10. Nanostructures graphene plasmon works close to near-infrared window

    DEFF Research Database (Denmark)

    Wang, Zhongli; Li, Tao; Almdal, Kristoffer

    Due to strong mode-confinement, long propagation-distance, and unique tunability, graphene plasmons have been widely explored in the mid-infrared and terahertz windows. However, it remains a big challenge to push graphene plasmons to shorter wavelengths in order to integrate graphene plasmon...... a promising way to promote graphene plasmons for both fundamental studies and potential applications in the near-infrared window....

  11. Radiation biology

    International Nuclear Information System (INIS)

    Neumeister, K.

    1977-01-01

    This chapter is included in a textbook which is primarily intended for medical students. The following topics are dealt with: radiation effects on molecules; chemical and biochemical radiation effects; modification of radiation effects and radiosensitivity; radiation-induced pathomorphological and pathophysiological effects in organs and organ systems; radiation syndrome; radiation effects in embryos and fetuses; genetic radiation effects; carcinogenesis and leukemogenesis after irradiation; and radiation effects after intake of radionuclides

  12. Application of infrared thermography in sports science

    CERN Document Server

    2017-01-01

    This book addresses the application of infrared thermography in sports, examining the main benefits of this non-invasive, non-radiating and low-cost technique. Aspects covered include the detection of injuries in sports medicine, the assessment of sports performance due to the existing link between physical fitness and thermoregulation and the analysis of heat transfer for sports garments and sports equipment. Although infrared thermography is broadly considered to be a fast and easy-to-use tool, the ability to deliver accurate and repeatable measurements is an important consideration. Furthermore, it is important to be familiar with the latest sports studies published on this technique to understand its potential and limitations. Accordingly, this book establishes a vital link between laboratory tests and the sports field. .

  13. Infrared radiometric technique in temperature measurement

    Science.gov (United States)

    Glazer, S.; Madding, R.

    1988-01-01

    One class of commercially available imaging infrared radiometers using cooled detectors is sensitive to radiation over the 3 to 12 micron wavelength band. Spectral filters can tailor instrument sensitivity to specific regions where the target exhibits optimum radiance. The broadband spectral response coupled with real time two-dimensional imaging and emittance/background temperature corrections make the instruments useful for remote measurement of surface temperatures from -20 C to +1500 C. Commonly used radiometric techniques and assumptions are discussed, and performance specifications for a typical modern commercial instrument are presented. The potential usefulness of an imaging infrared radiometer in space laboratories is highlighted through examples of research, nondestructive evaluation, safety, and routine maintenance applications. Future improvements in instrument design and application of the radiometric technique are discussed.

  14. 3D Temperature Distribution Model Based on Thermal Infrared Image

    Directory of Open Access Journals (Sweden)

    Tong Jia

    2017-01-01

    Full Text Available This paper aims to study the construction of 3D temperature distribution reconstruction system based on binocular vision technology. Initially, a traditional calibration method cannot be directly used, because the thermal infrared camera is only sensitive to temperature. Therefore, the thermal infrared camera is calibrated separately. Belief propagation algorithm is also investigated and its smooth model is improved in terms of stereo matching to optimize mismatching rate. Finally, the 3D temperature distribution model is built based on the matching of 3D point cloud and 2D thermal infrared information. Experimental results show that the method can accurately construct the 3D temperature distribution model and has strong robustness.

  15. Thomson scattering in strong external fields

    Science.gov (United States)

    Varró, S.; Ehlotzky, F.

    1992-09-01

    In the present paper we shall investigate relativistic Thomson scattering in two external fields. A free classical electron will be embedded in a strong, constant and homogeneous magnetic field and in a powerful electromagnetic field. Both fields will be considered in the Redmond configuration, in which case the electromagnetic wave is circularly polarized and propagates in the direction of the homogeneous magnetic field. The electron will be allowed to have arbitrary initial conditions and the electromagnetic wave will be switched on either suddenly or adiabatically. We shall present the exact solution of the Lorentz equation of motion in the above external field configuration and we shall evaluate the spectrum and cross sections of the scattered radiation. In particular, we shall consider scattering close to resonance and we shall compare our results with the findings of earlier work.

  16. Brown carbon absorption in the red and near infrared spectral region

    OpenAIRE

    Hoffer, András; Tóth, Ádám; Pósfai, Mihály; Chung, Chul Eddy; Gelencsér, András

    2017-01-01

    Black carbon aerosols (BC) have been conventionally assumed to be the only light-absorbing carbonaceous particles in the red and near-infrared spectral regions of solar radiation in the atmosphere. Here we report that contrary to the conventional belief tar balls (a specific type of organic aerosol particles from biomass burning) do absorb red and near infrared radiation significantly. Tar balls were produced in a laboratory experiment and their chemical and optical properties were measured. ...

  17. Brown carbon absorption in the red and near infrared spectral region

    OpenAIRE

    Hoffer, A.; Tóth, A.; Pósfai, M.; Chung, C. E.; Gelencsér, A.

    2016-01-01

    Black carbon aerosols have been conventionally assumed to be the only light-absorbing carbonaceous particles in the red and near-infrared spectral regions of solar radiation in the atmosphere. Here we report that contrary to the conventional belief tar balls (a specific type of organic aerosol particles from biomass burning) do absorb red and near infrared radiation significantly. Tar balls were produced in a laboratory experiment and their chemical and optical properties were measured. The a...

  18. Brown carbon absorption in the red and near-infrared spectral region

    OpenAIRE

    A. Hoffer; Á. Tóth; M. Pósfai; C. E. Chung; A. Gelencsér; A. Gelencsér

    2017-01-01

    Black carbon (BC) aerosols have often been assumed to be the only light-absorbing carbonaceous particles in the red and near-infrared spectral regions of solar radiation in the atmosphere. Here we report that tar balls (a specific type of organic aerosol particles from biomass burning) do absorb red and near-infrared radiation significantly. Tar balls were produced in a laboratory experiment, and their chemical and optical properties were measured. The absorption of these pa...

  19. The SNAP Strong Lens Survey

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, P.

    2005-01-03

    Basic considerations of lens detection and identification indicate that a wide field survey of the types planned for weak lensing and Type Ia SNe with SNAP are close to optimal for the optical detection of strong lenses. Such a ''piggy-back'' survey might be expected even pessimistically to provide a catalogue of a few thousand new strong lenses, with the numbers dominated by systems of faint blue galaxies lensed by foreground ellipticals. After sketching out our strategy for detecting and measuring these galaxy lenses using the SNAP images, we discuss some of the scientific applications of such a large sample of gravitational lenses: in particular we comment on the partition of information between lens structure, the source population properties and cosmology. Understanding this partitioning is key to assessing strong lens cosmography's value as a cosmological probe.

  20. Strong coupling phase in QED

    International Nuclear Information System (INIS)

    Aoki, Ken-ichi

    1988-01-01

    Existence of a strong coupling phase in QED has been suggested in solutions of the Schwinger-Dyson equation and in Monte Carlo simulation of lattice QED. In this article we recapitulate the previous arguments, and formulate the problem in the modern framework of the renormalization theory, Wilsonian renormalization. This scheme of renormalization gives the best understanding of the basic structure of a field theory especially when it has a multi-phase structure. We resolve some misleading arguments in the previous literature. Then we set up a strategy to attack the strong phase, if any. We describe a trial; a coupled Schwinger-Dyson equation. Possible picture of the strong coupling phase QED is presented. (author)