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This report summarizes our research on the interaction of infrared radiation, especially from high-intensity CO2 TEA lasers, with the cornea. The research reported here was performed between April 1, 1986 and April 14 1988. The report discusses threshold epithelial damage from single- and multiple-pulse exposures, material ejection from the anterior corneal surface, lesion histology, and possible damage mechanisms. Keywords: Laser effects; Laser hazards; RA 3; Cornea; Temporal; Spatial; Lab animals.

The first quarter of Calendar 1980 was spent installing and testing the newly acquired long-pulse well-regulated Physics International Pulserad 220 unit (1 Mev. 20 KA 100 nsec). The balance of the year was spent on the first phase of the FEL long pulse oscillator experiment and the beginnings of an investigation of the FEL amplifier. Wavelength and power were measured as a function of electron energy and current. Theoretical work included an exact analysis of particle dynamics in a true wiggler and the formulation of a simulation of a pump oscillated test particle in a plasma background, the latter study yielding new insights into finite Larmor radius effects. (Author)

The rotary forge at Watervliet Arsenal was surveyed for infrared hazards on 9-10 March 1978. It was found that levels of infrared exceeding protection standards for 10-second exposures were present at distances less than approximately 3 meters from the radiation source. This radiation would, however, be easily detected by exposed personnel due to body heating and would not, therefore, present a serious health hazard due to whole-body heating. However, eye protection against infrared was deemed necessary due to possible cataract formation from repeated exposures. (Author)

The rotary forge at Watervliet Arsenal was surveyed for infrared hazards on 9-10 March 1978. It was found that levels of infrared exceeding protection standards for 10-second exposures were present at distances less than approximately 3 meters from the radiation source. This radiation would, however, be easily detected by exposed personnel due to body heating and would not, therefore, present a serious health hazard due to whole-body heating. However, eye protection against infrared was deemed necessary due to possible cataract formation from repeated exposures. (Author)

The rotary forge at Watervliet Arsenal was surveyed for infrared hazards on 9-10 March 1978. It was found that levels of infrared exceeding protection standards for 10-second exposures were present at distances less than approximately 3 meters from the radiation source. This radiation would, however, be easily detected by exposed personnel due to body heating and would not, therefore, present a serious health hazard due to whole-body heating. However, eye protection against infrared was deemed necessary due to possible cataract formation from repeated exposures. (Author)

Current infrared-guided missiles can detect and destroy aircraft from relatively long distances. Future IR missiles will be even more sensitive and destructive. The engine designer must select cycles and engine configurations that present as small a target as possible to these missile threats. To accomplish this, he must know the IR emissions from the aircraft and be able to judge the success of schemes to suppress these emissions. Measurements are invaluable in determining the IR emissions for selected aircraft situations but cannot possibly be made for all aircraft and for all situations. This is obviously true in the engine design phase. In addition, understanding of the fundamental sources of these emissions is essential to the invention or evaluation of new suppression concepts. An accurate prediction pool, therefore, is vital to the process of reducing the vulnerability of an aircraft to IR-guided missiles. As a supplier of jet engines for military aircraft, the General Electric Company has developed a series of computer programs to predict the IR signatures and vulnerability of IR-guided missiles. The SCORPIO-N computer program presented in this report is the latest in the series. It is an outgrowth of the SCORPIO-IIIA program (Reference 1) and the SPRITE program (Reference 2) with improvements to the plume module which permit studies of truly three-dimensional flow fields. (Author)

Current infrared-guided missiles can detect and destroy aircraft from relatively long distances. Future IR missiles will be even more sensitive and destructive. The engine designer must select cycles and engine configurations that present as small a target as possible to these missile threats. To accomplish this, he must know the IR emissions from the aircraft and be able to judge the success of schemes to suppress these emissions. Measurements are invaluable in determining the IR emissions for selected aircraft situations but cannot possibly be made for all aircraft and for all situations. This is obviously true in the engine design phase. In addition, understanding of the fundamental sources of these emissions is essential to the invention or evaluation of new suppression concepts. An accurate prediction pool, therefore, is vital to the process of reducing the vulnerability of an aircraft to IR-guided missiles. As a supplier of jet engines for military aircraft, the General Electric Company has developed a series of computer programs to predict the IR signatures and vulnerability of IR-guided missiles. The SCORPIO-N computer program presented in this report is the latest in the series. It is an outgrowth of the SCORPIO-IIIA program (Reference 1) and the SPRITE program (Reference 2) with improvements to the plume module which permit studies of truly three-dimensional flow fields. (Author)

This report describes progress during the second year of our research program on Infrared Signature Masking by Air Plasmas at Stanford University. This program is intended to investigate the masking of infrared signatures by the air plasma formed behind the bow shock of high velocity missiles. Our previous annual report described spectral measurements and modeling of the radiation emitted between 3.2 and 5.5 microns by an atmospheric pressure air plasma in chemical and thermal equilibrium at a temperature of approximately 3100 K. One of our goals was to examine the spectral emission of secondary species such as water vapor or carbon dioxide. The cold air stream injected in the plasma torch contained approximately 330 parts per million Of CO2, which is the natural CO2 concentration in atmospheric air at room temperature, and a small amount of water vapor with an estimated mole fraction of 3.8 x 10(exp -4). As can be seen from Figure 1, it was found that the measured spectrum exhibited intense spectral features due to the fundamental rovibrational bands of NO at 4.9 - 5.5 microns and the V(3) band of CO2 (antisymmetric stretch) at 4.2-4.8 microns. These observations confirmed the well-known fact that infrared signatures between 4.15 - 5.5 microns can be masked by radiative emission in the interceptor's bow-shock. Figure I also suggested that the range 3.2 - 4.15 microns did not contain any significant emission features (lines or continuum) that could mask IR signatures. However, the signal-to-noise level, close to one in that range, precluded definite conclusions. Thus, in an effort to further investigate the spectral emission in the range of interest to signature masking problem, new measurements were made with a higher signal-to-noise ratio and an extended wavelength range.

The effects of ultraviolet radiation on the infrared reflectance of ZnO silicone white thermal coatings were investigated. Narrow band ultraviolet radiation for wavelengths in the 2200A to 3500A range by a monochromator and a high pressure, 150-W Eimac xenon lamp. The sample was irradiated while in a vacuum of at least 0.000001 torr, and infrared reflectance was measured in situ with a spectroreflectometer at 19,500A. Reflectance degradation was studied as a function of wavelength, time, intensity, and dose. Damage was wavelength dependent at constant exposure, but no maximum was evident above the shortest wavelength investigated here. The degradation rate at constant intensity was an exponential function of time and varies with intensity.

We report the discovery of excess K-band radiation from a massive DAZ white dwarf star, GD362. Combining infrared photometric and spectroscopic observations, we show that the excess radiation cannot be explained by a stellar or substellar companion, and is likely to be caused by a debris disk. This would be only the second such system known, discovered 18 years after G29-38, the only single white dwarf currently known to be orbited by circumstellar dust. Both of these systems favor a model with accretion from a surrounding debris disk to explain the metal abundances observed in DAZ white dwarfs. Nevertheless, observations of more DAZs in the mid-infrared are required to test if this model can explain all DAZs.

Your brain is bathed in sunlight Clip taken from DarkHorse Podcast Livestream #170 (originally streamed live on Apr 22, 2023): https://open.spotify.com/episode/0BjVco7udsmNcw0jsWapP2 https://youtube.com/live/H9INkQAW6t8?feature=share Q&A: https://open.spotify.com/episode/0EZ4ZBEBTP5406VUxAwwuR https://youtube.com/live/eXaGDO-tpjI?feature=share References: It is dark inside your head: https://open.substack.com/pub/naturalselections/p/it-is-dark-inside-your-head History of Earth Day: https://www.earthday.org/history/ The Unsettling of America: Culture and Agriculture (Wendell Berry, 1977): https://www.amazon.com/Unsettling-America-Culture-Agriculture/dp/161902599X What is this a clip from? In this 170th in a series of live discussions with Bret Weinstein and Heather Heying (both PhDs in Biology), discuss the state of the world though an evolutionary lens. Find more from us on Bret’s website (https://bretweinstein.net) or Heather’s website (http://heatherheying.com). Heather’s newsletter, Natural Selections (subscribe to get free weekly essays in your inbox): https://naturalselections.substack.com A Hunter-Gatherer’s Guide to the 21st Century is now available: https://huntergatherersguide.com/ DarkHorse merchandise now available at: http://store.darkhorsepodcast.org/ Become a member of the DarkHorse Livestreams, and get access to an additional Q&A livestream every month. Join at Heather's Patreon. https://www.patreon.com/heatherheying Like this content? Subscribe to the channel, like this video, follow us on twitter (@BretWeinstein, @HeatherEHeying), and consider helping us out by contributing to either of our Patreons or Bret’s Paypal. https://www.patreon.com/bretweinstein Theme Music: Thank you to Martin Molin of Wintergatan for providing us the rights to use their excellent music.

High-energy radiation from T Tauri stars (TTS) influences the amount and longevity of gas in disks, thereby playing a crucial role in the creation of gas giant planets. Here we probe the high-energy ionizing radiation from TTS using high-resolution mid-infrared (MIR) Spitzer IRS Neon forbidden line detections in a sample of disks from IC 348, NGC 2068, and Chamaeleon. We report three new detections of [Ne III] from CS Cha, SZ Cha, and T 54, doubling the known number of [Ne III] detections from TTS. Using [Ne III]-to-[Ne II] ratios in conjunction with X-ray emission measurements, we probe high-energy radiation from TTS. The majority of previously inferred [Ne III]/[Ne II] ratios based on [Ne III] line upper limits are significantly less than 1, pointing to the dominance of either X-ray radiation or soft Extreme-Ultraviolet (EUV) radiation in producing these lines. Here we report the first observational evidence for hard EUV dominated Ne forbidden line production in a T Tauri disk: [Ne III]/[Ne II]~1 in SZ Cha. Our results provide a unique insight into the EUV emission from TTS, by suggesting that EUV radiation may dominate the creation of Ne forbidden lines, albeit in a minority of cases.

Furnace produces controlled heat for brazing and heat treating metals over a wide range of temperatures by using a near-infrared heat source positioned at one focus of an ellipsoidal reflector mounted below a cylindrical quartz chamber. This furnace maintains a pure atmosphere, has rapid heatup and cooldown, and permits visual observation.

In the center of active galactic nuclei (AGN), the dusty torus absorb the radiation from the central engine and re-emit in mid-infrared (MIR). Observations have detected moderate anisotropy in the dust MIR emission, in the way that type 1 AGNs (type1s) are mildly brighter in MIR comparing with type 2 sources (type2s). However, type1s and type2s were found to follow statistically the same tight MIR -- hard X-ray correlation, suggesting the MIR emission is highly isotropic assuming the hard X-ray radiation is inclination independent. We argue this discrepancy could be solved considering the hard X-ray emission in AGN is also mildly anisotropic as we recently discovered. To verify this diagram, we compare the sub-arcsecond 12\mu m flux densities of type1s and type2s using [OIV]$\lambda$25.89\mu m emission line as an isotropic luminosity indicator. We find that on average type1s are brighter in nuclei 12\mu m radiation by a factor of $2.6 \pm 0.6$ than type2s at given [OIV]$\lambda$25.89\mu m luminosities, confirming the mild anisotropy of the nuclei 12\mu m emission. We show that the anisotropy of the 12\mu m emission we detected is in good agreement with radiative transfer models of clumpy torus. The fact that type 1 and type 2 AGNs follow the same tight MIR -- hard X-ray correlation instead supports that both the MIR and hard X-ray emission in AGNs are mildly anisotropic.

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. Non-local thermodynamic equilibrium, Infrared radiation, Computer code, Vibrational and rotational levels, Limb radiance.

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. (MM)

A low power CO2 laser has been used to kill a spore preparation of Bacillus Subtilis. The CO2 laser has been found to be very effective in deactivating these spores. A 65 watt/sq cm beam reduced the dry live spore population by 3 orders of magnitude in 0.4 seconds as compared to a reduction by one order of magnitude after 60 seconds exposure (150 times as long) to pressurized steam at 130 C. A possible explanation of the high efficiency of laser sterilization may be deactivation by resonant absorption of infrared energy at 10.6 mu. Experiments discussing selected damage in proteins are presented. (Author)

Heat transfer by infrared radiation in the atmosphere, Walter M. Elsasser, Harvard Meteorological Studies No. 6, Harvard University, Blue Hill Meteorological Observatory, Milton, Massachusetts, 1942.

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.

Retinal damage thresholds from 100-millisecond exposures to laser radiation for wavelengths between 1,100 and 1,350nm have never previously been established. We sought to determine the retinal damage threshold for 100- millisecond exposures of near-infrared (NIR) laser radiation wavelengths at 1,110, 1,130, 1,150, and 1,319 nm. These data were then used to create trends for retinal damage thresholds over the 1,100?1,350nm NIR region based upon linear absorption of laser radiation in ocular media and chromatic dispersion of the eye.

In this report, we present the design, fabrication, and characterization of several high performance multi-color and broadband quantum well infrared photodetectors (QWIPs) for both MWIR and LWIR applications. The report covers tasks performed during the period from March 3, 1998 through July 10, 1999. A very high sensitivity, high-strain, multi-color triple-coupled (TC-) QWIP using InGaAs/AlGaAs/InGaAs material systems has been developed in this project for LWIR multi-color detection. A two-stack InGaAs/AlGaAs/InGaAs TC-QWIP and InGaAs/AlGaAs TC-QWIP has been developed for the LWIR and MWIR dual-band detection. In addition, a high-strain InGaAs/GaAs TC-QWIP with and without two-dimensional (2-D) grating coupler has been designed, fabricated, and characterized for the LWIR detection. This device shows very high responsivity under 450 back-illumination. Several broadband (BB-) QWIPs have been developed for the LWIR detection. These include (1) two-stack, five-well n-type InGaAs/AlGaAs broadband (BB-) QWIPs with 3- and 7-period QWs in the unit cell, (2) 3- and 4-well n-type BB-QWIPs, and (3) two 3- and 4- well p-type BB-QWIPs. In addition, a three-stack InGaAs/AlGaAs/InGaAs BB TC-QWIP grown on GaAs substrate has been developed for LWIR detection, which has a FWHM spectral bandwidth twice larger than the single-stack TC-QWIP. Finally, a MWIR InGaAs/InAlAs TC-QWIP grown on InP substrate, operating up to T = 116K with excellent device performance, has also been demonstrated. Four journal papers and six conference papers have been published and presented from this work.

All of the N2O bands expected to absorb significantly between 4000 and 6700/cm have been listed, and the strengths of several of the stronger bands have been determined. Spectral curves are shown for samples at low pressure so that the line structure remains and for samples at approximately 15 atm with the structure smoothed out.

The current work is a preliminary study to planned direct measurement of the infrared emissions of a projectile in flight, from which surface temperature will be estimated. If the planned experiment is to be meaningful, the projectile surface temperature must be high enough such that the incident infrared radiation is significant enough to e measured by the detectors. In this report, detector threshold is calculated and compared to the computed infrared radiation reaching the detector from an M735 projectile nosecone at a distance from the muzzle of 225 meters. In the wavelength band 2.0 - 2.5 mu, the results predict that the detector will not be able to see the projectile emissions, and in the wavelength band 3.5 4.0 mu, the results show probable detection of most of the projectile only if the flow is turbulent... Infrared radiation, Projectiles, Surface Temperature.

This report investigates the applicability of the standard LOWTRAN atmospheric models to four typical Australian environments and considers the effects to these environments upon the transmission of 3 to 5 um radiation. It is found that the LOWTRAN model atmospheres can be useful in Australian conditions, and advice is given as to the most appropriate models to use depending upon the path and environment conditions. The extent to which model data is used rather than real data will affect the transmittance predictions; the magnitude of this effect is given, indicating that there is particular value in measuring water vapour content (shown to be the most significant meteorological parameter) in the lowest few kilometers through which the path passes. Transmittance as a function of range (and vice versa) is considered for all slant path angles from vertical to horizontal. Graphical results are presented in full as a resource to be consulted given a particular site ad path transmittance prediction requirement. Keywords: Infrared radiation; Atmospheric models; Slant paths; Australia.

A computer code that calculates infrared radiance in the upper atmosphere has been developed. The code, for limb-looking geometry and conditions where local thermodynamic equilibrium may not hold, utilizes individual ro-vibrational transitions to calculate the optical thicknesses along each segment of the line-of-sight path. The formulation of the problem is given, as is the means of using the program and the procedure for obtaining input data from certain data bases. Appendices contain program listings and two examples. (Author)

Infrared surveys provide essential insights on galaxy evolution. If near-IR studies suggest mild evolution of stellar populations with cosmic time, indications of a substantial evolution have been seen in the far-IR, although the available information is largely insufficient to delineate precise evolutionary properties. A consistent picture encompassing all the currently available data may be obtained assuming that dust extinction hides the early evolutionary phases of spheroidal galaxies in the optical band, while the corresponding dust re-radiation in the far-IR may have been, during the early evolutionary phases, orders of magnitude larger than today. Hyperluminous IRAS galaxies might be extreme examples of this situation. Additional indications that at least some spheroidal galaxies may have been very dusty during their early evolution are provided by recent data on high redshift radio galaxies and quasars. Galaxies are the likely dominant contributors to the IR background. However, in the framework of unified models for Active Galactic Nuclei, a large number of nuclei hidden by a dusty torus may be expected. Implications for the IR background are discussed.

This report summarizes the results obtained during a research program on the infrared radiation of air plasmas conducted in the High Temperature Gasdynamics Laboratory at Stanford University under the direction of Professor Charles H. Kruger, with Dr. Christophe O. Laux as Associate Investigator. The goal of this research was to investigate the masking of infrared signatures by the air plasma formed behind the bow shock of high velocity missiles. To this end, spectral measurements and modeling were made of the radiation emitted between 2.4 and 5.5 micrometers by an atmospheric pressure air plasma in chemical and thermal equilibrium at a temperature of approximately 3000 K. The objective was to examine the spectral emission of air species including nitric oxide, atomic oxygen and nitrogen lines, molecular and atomic continua, as well as secondary species such as water vapor or carbon dioxide. The cold air stream injected in the plasma torch contained approximately 330 parts per million of CO2, which is the natural CO2 concentration in atmospheric air at room temperatures, and a small amount of water vapor with an estimated mole fraction of 3.8x10(exp -4).

The gravitational field is probed in a search for polarization dependence in the light bending. This involves searching for a splitting of a source image into orthogonal polarizations as the radiation passes through the solar gravitational field. This search was carried out using the techniques of very long and intermediate baseline interferometry, and by seeking a relative phase delay in orthogonal polarizations of microwaves passing through the solar gravitational field. In this last technique a change in the total polarization of the Helios 1 carrier wave was sought as the spacecraft passed behind the sun. No polarization splitting was detected.

Radiation from a crimped V-groove in the electrically heated metallic element of a high-resolution infrared spectrometer is more intense than that from plane areas adjacent to the element. Radiation from the vee and the flat was compared by alternately focusing on the entrance slit of a spectrograph.

This report summarizes the results obtained during a research program on the infrared radiation of air plasmas conducted in the High Temperature Gasdynamics Laboratory at Stanford University under the direction of Professor Charles H. Kruger, with Dr. Christophe O. Laux as Associate Investigator. The goal of this research was to investigate the masking of infrared signatures by the air plasma formed behind the bow shock of high velocity missiles. To this end, spectral measurements and modeling were made of the radiation emitted between 2.4 and 5.5 micrometers by an atmospheric pressure air plasma in chemical and thermal equilibrium at a temperature of approximately 3000 K. The objective was to examine the spectral emission of air species including nitric oxide, atomic oxygen and nitrogen lines, molecular and atomic continua, as well as secondary species such as water vapor or carbon dioxide. The cold air stream injected in the plasma torch contained approximately 330 parts per million of CO2, which is the natural CO2 concentration in atmospheric air at room temperatures, and a small amount of water vapor with an estimated mole fraction of 3.8x10(exp -4).

Detection of infrared radiation emission from semiconductor devices

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In this work we investigated the InAs/InAlAs quantum wires (QWRs) superlattice by optically exciting the structure with near-infrared radiation. By varying the helicity of the radiation at room temperature we observed the circular photogalvanic effect related to the $C_{2v}$ symmetry of the structure, which could be attributed to the formation of a quasi two-dimensional system underlying in the vicinity of the QWRs pattern. The ratio of Rashba and Dresselhaus terms shows an evolution of the spin-orbit interaction in quasi two-dimensional structure with the QWR layer deposition thickness.

This article is from Scientific Reports , volume 4 . Abstract The thermal (emitted) infrared frequency bands, from 20–40 THz and 60–100 THz, are best known for applications in thermography. This underused and unregulated part of the spectral range offers opportunities for the development of secure communications. The ‘THz Torch' concept was recently presented by the authors. This technology fundamentally exploits engineered blackbody radiation, by partitioning thermally-generated spectral noise power into pre-defined frequency channels; the energy in each channel is then independently pulsed modulated and multiplexing schemes are introduced to create a robust form of short-range secure communications in the far/mid infrared. To date, octave bandwidth (25–50 THz) single-channel links have been demonstrated with 380 bps speeds. Multi-channel ‘THz Torch' frequency division multiplexing (FDM) and frequency-hopping spread-spectrum (FHSS) schemes have been proposed, but only a slow 40 bps FDM scheme has been demonstrated experimentally. Here, we report a much faster 1,280 bps FDM implementation. In addition, an experimental proof-of-concept FHSS scheme is demonstrated for the first time, having a 320 bps data rate. With both 4-channel multiplexing schemes, measured bit error rates (BERs) of < 10−6 are achieved over a distance of 2.5 cm. Our approach represents a new paradigm in the way niche secure communications can be established over short links.

SEMI-INFRARED PHOTOGRAPH OF A J-35 VAPORIZER RIG SHOWING RADIATION GLOW

The report describes an analytical model for predicting the emission of radiation from a jet plume in the mid-infrared spectral region. It is assumed that the dominant radiation arises for the CO2 molecule. Results are therefore reported for the 4.3-micrometer band of gaseous carbon dioxide which is assumed to cover the spectral region 2050 to 2400/cm (4.17 - 4.88 micrometers). The temperature range that is considered varies from 300 to 2100 deg K. The objective of the reported program was to develop a computerized program for predicting radiant energy emissions which could be readily integrated into a flow field calculation. A description is given of both the radiation model and the flow field model. The described program provides both the spectral and spatial intensity distributions of the emitted radiation.

The report describes an analytical model for predicting the emission of radiation from a jet plume in the mid-infrared spectral region. It is assumed that the dominant radiation arises for the CO2 molecule. Results are therefore reported for the 4.3-micrometer band of gaseous carbon dioxide which is assumed to cover the spectral region 2050 to 2400/cm (4.17 - 4.88 micrometers). The temperature range that is considered varies from 300 to 2100 deg K. The objective of the reported program was to develop a computerized program for predicting radiant energy emissions which could be readily integrated into a flow field calculation. A description is given of both the radiation model and the flow field model. The described program provides both the spectral and spatial intensity distributions of the emitted radiation.

Absorption of black-body radiation by ice cryodeposits on metal substrates

The activities on the HIRS program are described for the period of July through September, 1973. Completion of design activity and early fabrication effort on the protoflight unit were the major efforts. Operation of the engineering model in spacecraft integration tests was completed during July and August, after which the unit was returned for added test and evaluation.

A new scheme for generation of coherent radiantion on the intersubband transition without population inversion between subbands is presented. The scheme is based on the resonant nonlinear mixing of the optical laser fields on the two interband transitions which are generated in the same active region and serve as a coherent drive for the infrared field. This mechanism for frequency self-conversion can work efficiently at room temperature and with injection current pumping. Due to the parametric nature of infrared generation the proposed inversionless scheme is especially promising for long-wvavelength (far-infrared) operation.

The spatial distribution of 11 micron radiation from omicron Ceti was observed at various phases of its light cycle using a stellar interferometer. Changes were seen which can be attributed to variation in the strength of thermal emission from circumstellar dust relative to the stellar continuum at 11 microns. These changes are shown to be correlated with the changes in luminosity of micron Ceti in such a way that dust grain emission at 11 microns was increased more than the continuum during the period of maximum luminosity. The degree of the change in dust grain emission implies that the maximum dust temperature is in the range of 500 K to 700 K during minimum stellar luminosity.

Detecting geomorphological features over Northeast Africa by Nimbus 2 visible and infrared radiation measurements

This viewgraph presentation describes a test simulate the transient effects of cosmic ray impacts on near infrared focal plane arrays. The objectives of the test are to: 1) Characterize proton single events as function of energy and angle of incidence; 2) Measure charge spread (crosstalk) to adjacent pixels; 3) Assess transient recovery time.

[1] Introduction: Fruits and their products in the dried form are good sources of vitamins, energy and minerals. However, during the process of drying or dehydration there are changes in quality parameters in dried products. Texture is one of the most important quality attributes of fruits during drying, reflecting their mechanical and microstructural properties. Apple is perishable fruit. Drying of apple is very important because of High losses are experienced during the seasonal glut. A novel process in food industry is the simultaneous infrared dry blanching and dehydration operation (SIRDBD) with intermittent heating method (radiation at constant temperature) exerted on fruits and vegetables that is known to enhance the quality of the final product. In the food industry, end-products must achieve a compromise between several properties, including sensory, sanitary and technological properties. Prediction of changes in texture during drying could be helpful in a better process control and improvement in overall acceptability of a dried snack food. The change of the elastic or viscoelastic texture of the fresh apples to rigid, fragile and brittle in the apple chips were evaluated by instrumental and sensory methods. Many attempts have been made to describe the viscoelastic behavior of dehydrated fruits and vegetables. Maxwell’s or compression models are limited to homogeneous, isotropic materials. In contrast, texture profile analysis (TPA) is more suitable for heterogeneous biological materials and shows a good correlation with organoleptic evaluation. Typical TPA parameters are including hardness, adhesiveness, springiness, cohesiveness, gumminess, chewiness and resilience. In this research, for the first time, textural analysis of dried apple slices by infrared heating at different temperatures and different moisture levels was performed. Finally, the optimum texture and overall acceptance of the product are described according to the instrumental analysis.   Materials and methods: Apples ( Golden Delicious variety) were purchased from a local market and kept in 0°C±1°C and relative humidity ranging from 90% to 95%. Before every thermal processing, the apple specimens were picked up from the cold storage and then they were put into use after reaching the ambient temperature. The samples were skinned manually and then cut into slices with different thicknesses of 5mm, 9mm and 13mm, all 20mm in diameter. The sliced apples were immediately subjected to simultaneous blanching and infrared drying. The texture of dehydrated apple slices using infrared radiation at three surface temperatures of 70, 75 and 80 °C were studied. The product in three thicknesses was dried to achieve a moisture level of 15, 20 and 25% wet weight basis. Then, texture profile analysis (TPA) was carried out to 50% compression strain using texture analyzer. The sensory evaluation of dried slices was also considered for desire texture (Good mouth feels texture, lack of hard tissue, no shrinkage) and overall acceptance (The final acceptability of the product in terms of total sensory properties including color, texture, flavor and aroma) by 10 professional panelists. For statistical analysis, a completely randomized design (CRD) was used in a factorial form (3 3 ) and Duncan test with 95% confidence level.   Result & Discussion: The results showed that drying to studied moisture levels reduced the hardness and adhesiveness and increased springiness, cohesiveness, gumminess, chewiness and resilience in comparison with raw apple tissue. Hardness of samples dried at higher temperature was higher due to rapid removal of moisture which might have caused collapse of capillary voids inside the product. Due to shrinkage samples became denser and thus a larger fracture force was to be expected. As water content increases (i.e., higher RH) water plasticizes the cell walls and the material and product becomes softer and more pliable, thus hardness decreases. The increase of hardness could be because the rapid mass transfer that damaged the membrane and cell structure of the fruits during drying. Another important factor responsible for the increase of hardness of finish-dried samples is the low final moisture content when compared with other samples. High temperature drying method enables samples to reach low moisture content at relatively short duration and therefore the product with harder texture was obtained. The maximum value of adhesiveness was observed for fresh apples, which could be attributed to the high moisture and sugar content. Adhesiveness decreased with moisture loss, indicating the availability of free water on the sample surface. A significant decrease in springiness following high-temperature drying could be attributed to the glass transition phenomenon and changes from elastic to plastic behavior. In the period of softening, cohesiveness increased with moisture loss. Hardening caused a decrease in cohesiveness depending on the drying temperature. Gumminess is the energy required to disintegrate a semisolid food to a state of readiness for swallowing. High values of gumminess revealed “firm” and “crisp” with a cell rupture mode of tissue failure and lowest values of gumminess could be classified as “soft”.   At the end of drying and with apple hardening, chewiness increased to values equal or above initial chewiness, indicating that a larger amount of energy is needed to masticate dried apples. Resilience had increasing with moisture loss. By increasing the thickness of the slices, the cohesiveness and springiness decreased and hence chewiness significantly decreased. The overall acceptance and desire texture in dried samples was observed at lower water evaporation rate conditions (lower temperatures, lower thickness and higher moisture content). In these conditions, the hardness of apple slices tissue was equal to 695.177 ± 7.685 grams. During drying of the apple, textural behavior was varied from the viscoelastic (higher initial hardness, with cohesiveness, springiness and lower resilience) to elastic and then to plastic or glassy.

This report describes a new software tool, ATRAN, which computes the transmittance of Earth's atmosphere at near- and far-infrared wavelengths. We compare the capabilities of this program with others currently available and demonstrate its utility for observational data calibration and reduction. The program employs current water-vapor and ozone models to produce fast and accurate transmittance spectra for wavelengths ranging from 0.8 microns to 10 mm.

The HIRS/2 is provided for the TIROS-N series of operational meteorological satellites. The instrument features 20 spectral channels, including visible (.7 micron), shortwave (3.7 to 4.6 micron), and longwave (6.7 to 15 micron). Radiance data aids determination of vertical temperature profiles, water vapor, and ozone distribution. System performance and test results are described.

Color photogrammetry for Nimbus infrared radiation data analysis

This article is from F1000Research , volume 2 . Abstract Cyanobacteria in the genus Acaryochloris have largely exchanged Chl a with Chl d, enabling them to harvest near-infrared-radiation (NIR) for oxygenic photosynthesis, a biochemical pathway prone to generate reactive oxygen species (ROS). In this study, ROS production under different light conditions was quantified in three Acaryochloris strains (MBIC11017, HICR111A and the novel strain CRS) using a real-time ethylene detector in conjunction with addition of 2-keto-4-thiomethylbutyric acid, a substrate that is converted to ethylene when reacting with certain types of ROS. In all strains, NIR was found to generate less ROS than visible light (VIS). More ROS was generated if strains MBIC11017 and HICR111A were adapted to NIR and then exposed to VIS, while strain CRS demonstrated the opposite behavior. This is the very first study of ROS generation and suggests that Acaryochloris can avoid a considerable amount of light-induced stress by using NIR instead of VIS for its photosynthesis, adding further evolutionary arguments to their widespread appearance.

This article is from Frontiers in Oncology , volume 4 . Abstract The objective was to use carbon nanotubes (CNT) coupled with near-infrared radiation (NIR) to induce hyperthermia as a novel non-ionizing radiation treatment for primary brain tumors, glioblastoma multiforme (GBM). In this study, we report the therapeutic potential of hyperthermia-induced thermal ablation using the sequential administration of carbon nanotubes (CNT) and NIR. In vitro studies were performed using glioma tumor cell lines (U251, U87, LN229, T98G). Glioma cells were incubated with CNTs for 24 h followed by exposure to NIR for 10 min. Glioma cells preferentially internalized CNTs, which upon NIR exposure, generated heat, causing necrotic cell death. There were minimal effects to normal cells, which correlate to their minimal uptake of CNTs. Furthermore, this protocol caused cell death to glioma cancer stem cells, and drug-resistant as well as drug-sensitive glioma cells. This sequential hyperthermia therapy was effective in vivo in the rodent tumor model resulting in tumor shrinkage and no recurrence after only one treatment. In conclusion, this sequence of selective CNT administration followed by NIR activation provides a new approach to the treatment of glioma, particularly drug-resistant gliomas.