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We present a review of methods for measuring the quantum efficiency of infrared photodiodes, and briefly analyze their applicability and achievable accuracy. A new measurement method is proposed based on the postulate that the ratio of the derivatives of the spectral dependences of the signals from real and ideal photodiodes is equal to the quantum efficiency of a real photodiode. The measurement equation is justified theoretically, the expected uncertainty of the measurement results is estimated, an example of implementing the proposed method is presented, and practical recommendations are made. [ABSTRACT FROM AUTHOR]

IR lasers are widely used in various fields of science and technology. In this regard, expanding the spectral range and obtaining effective lasing in the IR is an urgent task. The object of our study is an self-terminating Eu laser radiating at a wavelength of 1.76 μm. We study a possibility of increasing the output parameters of this laser by elongating the active zone of a gas discharge tube (GDT). An increase in the GDT volume from 157 to 314 cm3 at a constant pumping power of 1200 W makes it possible to double the output power and laser efficiency. An average radiation power of 2.5 W was attained for the first time in 1.76 μm line; a maximal efficiency of 0.3% was attained at a pump power of 500 W. After 100 hours of operation, the energy characteristics of the Eu + Ne laser with the active zone of 314 cm3 in volume show good repeatability, which allows us to conclude a possibility of further increasing the energy characteristics and lifetime of this laser. Our results can be useful in microprocessing of materials and in active optical systems for visualizing fast processes. [ABSTRACT FROM AUTHOR]

This paper presents a technique for measuring the temperature of an inhomogeneous underlying surface using unmanned aerial vehicles (UAVs). To test the proposed technique, measurements over various landscapes are presented: dunes in an arid zone, a temperate swamp, a subarctic city, and a combination of natural and anthropogenic landscapes in the Arctic. A measuring complex based on a DJI Mavic 2 Zoom quadrocopter with a Flir TAU 2R thermal camera is used. Methods for correcting emerging hardware errors and artefacts have been developed. To obtain detailed data on the spatial distribution of the surface brightness temperature, the orthomosaic construction method is used. Thermal maps of surfaces with surface height inhomogeneities (dunes), moisture inhomogeneity (swamps), and urban areas in polar and subpolar conditions are obtained at different times of the day. It is shown that thermal contrasts can reach the first tens of degrees Celsius within an area of 10–20 ha, both under the background of daytime heating and nighttime cooling of the surface, and could have a significant effect on the spatial distribution of the heat transfer characteristics of the atmosphere and the underlying surface. These methods are recommended for constructing surface thermal maps using thermal imaging technology. [ABSTRACT FROM AUTHOR]

The model of the atmosphere in the form of a sequence of homogeneous layers 100 m in thickness from the surface of the Earth to a height of 40 km is considered. Layer parameters are defined for the standard atmosphere. Spectral sections of 1002–1003 and 1020–1021 cm0–1 with an opposite dependence of ozone absorption coefficient on its temperature change are selected. This model was transformed into one efficient homogeneous layer. The contribution to the outgoing radiation of the atmosphere in the selected spectral regions of the ozone absorption band (1002–1003 and 1020–1021 cm–1) is equal to the contributions to the outgoing radiation of the Earth by all nonuniform layers constituting them. The possibility of adjusting the temperature of the Earth's underlying surface is shown. The method of calculating the ozone content in the atmosphere by the outgoing radiation of the Earth is considered. [ABSTRACT FROM AUTHOR]

A technique is proposed for the formation of a developed regular structure on the surface of a polished single-crystal silicon wafer by ion-beam etching. It is shown that when single-crystal silicon is etched by a beam of accelerated Ar+ ions with normal ion incidence on the sample surface, a surface region with a developed relief is formed, which can serve as a reflection-reducing layer. The reflection of radiation with wavelengths of 532, 633, 780, and 980 nm from a sample of single-crystal silicon with the orientation of the surface cut {100}, subjected to ion-beam treatment with Ar+ ions with an energy of Eion = 400 eV for 10 hours (material removal was 7.5 µm) is studied. The specular-reflection curves of s-polarized radiation are obtained as functions of the angle of incidence. A decrease in the reflection coefficient relative to a polished silicon wafer is found at all investigated wavelengths. The largest decrease (more than 4 times) is recorded for a wavelength of 532 nm. It is shown that the range of heights of inhomogeneities formed during ion-beam etching increases linearly with an increase in the depth (time) of etching, which can be used to optimize the relief for a given wavelength. [ABSTRACT FROM AUTHOR]

Herein, the thermoelectric characteristics of polytriarylamine‐Lewis acid complex films were investigated by employing a horizontal device structure. Poly[N,N′‐bis(4‐butylphenyl)‐N,N′‐bis(phenyl)benzidine] (PolyTPD) is doped with tris(pentafluorophenyl)borane (BCF) via Lewis acid–base reactions by varying the BCF molar ratio (0–300 mol%). The resulting PolyTPD:BCF films are spun on glass substrates and silver electrodes are deposited leading to the horizontal type of organic thermoelectric devices (OTEDs). The OTEDs with the PolyTPD:BCF films are examined by varying temperature differences up to 45 K between two silver electrodes directly contacting hot/cold sources. Both device current and voltage are proportionally increased with the temperature difference, leading to higher powers at larger temperature differences, irrespective of BCF molar ratio. However, the highest current is achieved at 50 mol% owing to the highest electrical conductivity, even though the device voltage is slightly lower at 50 than 20 mol%. The origin of high electrical conductivity is assigned to the formation of radical cations in PolyTPD chains by BCF doping, which is influenced by the reaction time. The device current can be also generated by the illumination of IR radiation (noncontact mode) that is away from the OTEDs with the PolyTPD:BCF films. [ABSTRACT FROM AUTHOR]

Herein, the thermoelectric characteristics of polytriarylamine‐Lewis acid complex films were investigated by employing a horizontal device structure. Poly[N,N′‐bis(4‐butylphenyl)‐N,N′‐bis(phenyl)benzidine] (PolyTPD) is doped with tris(pentafluorophenyl)borane (BCF) via Lewis acid–base reactions by varying the BCF molar ratio (0–300 mol%). The resulting PolyTPD:BCF films are spun on glass substrates and silver electrodes are deposited leading to the horizontal type of organic thermoelectric devices (OTEDs). The OTEDs with the PolyTPD:BCF films are examined by varying temperature differences up to 45 K between two silver electrodes directly contacting hot/cold sources. Both device current and voltage are proportionally increased with the temperature difference, leading to higher powers at larger temperature differences, irrespective of BCF molar ratio. However, the highest current is achieved at 50 mol% owing to the highest electrical conductivity, even though the device voltage is slightly lower at 50 than 20 mol%. The origin of high electrical conductivity is assigned to the formation of radical cations in PolyTPD chains by BCF doping, which is influenced by the reaction time. The device current can be also generated by the illumination of IR radiation (noncontact mode) that is away from the OTEDs with the PolyTPD:BCF films.

Based on the results of computational and experimental studies, it is shown that the use of a cesium–rubidium alloy as a plasma-forming medium in serial pulsed sources of IR radiation is promising. It was found that at a 25% weight content of rubidium in an alloy with cesium, the vapor pressure and thermal conductivity of the plasma are close to the specified characteristics of a serial flash lamp filled with cesium amalgam. The results made it possible to increase the peak radiation power and create an environmentally friendly pulsed source of infrared radiation. [ABSTRACT FROM AUTHOR]

Thermal comfort is essential for human well-being, influencing our perception of surrounding thermal conditions. Achieving thermal comfort typically requires energy for cooling or heating, prompting researchers to advocate for personal technologies due to their lower energy consumption (active on-body systems) compared to traditional methods (off-body systems). Advanced textiles are promoted as a sustainable solution, providing thermal comfort over a wider temperature range without additional energy consumption (passive on-body systems). This comprehensive review examines various types of comfort, with a focus on thermal comfort, exploring influencing factors and standards for assessing advanced textile performance. Additionally, the study emphasizes the importance of developing infrared (IR) emission control technologies to enhance thermal comfort, as radiant heat significantly contributes to body heat loss. Recent advancements in passive radiative cooling/heating layer fabrication are discussed. Among the technologies utilized for creating layers with radiant heat control properties, electrospinning technology is emphasized in this study. Electrospinning technology, renowned for its simplicity, compatibility with other methods, controllability, repeatability, and burgeoning industrial applications, is of particular interest to researchers. This article explores how passive design of electrospun layers can enhance radiant heat reflection and absorption for heating and cooling purposes. These layers are passive smart textiles that adapt to weather conditions using particles added during fabrication. The article discusses the advantages and challenges of this approach, highlighting the potential of electrospinning technology in creating smart textiles with improved thermal properties. The overarching goal is to aid ongoing research in achieving thermal comfort across diverse environments. [ABSTRACT FROM AUTHOR]

The yield of obtaining layered double hydroxides (LDHs) remains a significant challenge that limits their practical use on a large scale. The use of flow processes is an innovative approach to solving the problem. This paper describes a method for obtaining LDH nanoparticles using an agitated tube reactor heated by infrared radiation (flow-IR-ATR). As a dedicated reactor for production of LDH nanoparticles, it is able to synthesise products at a flow rate of 1.8 dm3/h and a yield of 40 g/h. In the process, LDH NPs based on zinc–aluminium hydroxides (Zn–Al LDH) and LDH NPs modified with nickel hydroxide (Ni–Zn–Al LDH), with molar ratio of Ni to Zn 0.5, were obtained. Instrumental analyses (XRD, FTIR, SEM, DLS, BET, XPS) were used to characterise the LDH nanoparticles obtained, which showed crystallite sizes from 9 to 35 nm. The nickel-containing LDHs exhibited high photocatalytic activity. After 60 min, in the presence of UV radiation (365 nm), the photodegradation efficiency of quinoline yellow (dye concentration of 100 mg/dm3) was more than 99.9%. [ABSTRACT FROM AUTHOR]

Study of optical properties of nanoscale membranes of porous anodic alumina can significantly expand the scope of this material. The paper presents the results of thermal imaging studies of porous anodic alumina membranes with various structural parameters. Temperature distribution profiles for membranes obtained in various electrolytes based on sulfuric, oxalic and orthophosphoric acids have been constructed. It was found that the shielding of IR radiation is more pronounced (approximately 30%) in membranes with a smaller pore diameter dspore≈20 nm compared to membranes with a larger pore diameter dlpore≈200 nm. This is due to the scattering of thermal radiation on structural inhomogeneities, which are much higher in porous anodic alumina membranes obtained with sulfuric acid. Small-diameter pores, under-etched areas and defects act as sources of inhomogeneity. Also, due to the increased activity of sulfuric acid in comparison with other acids used, more anions are incorporated into the structure of the sample.

In the paper, comparative studies of near-IR photoluminescence (PL) in structures with GaAs/AlGaAs quantum wells possessing different selective doping profiles have been performed. The PL spectra recorded at 5 K for different intensities of interband optical pumping were analyzed and main channels of radiative recombination were determined. The dependences of the main PL line intensities on the pump level were obtained. The results of the studies performed suggest that n-GaAs/AlGaAs nanostructures with the compensating acceptor impurity located not in the n-GaAs quantum well, but in its barriers, are preferable for terahertz radiation generation.

Simple Summary: Process operators have an important monitoring role in the petrochemical industry. In the event of process disruptions and incidents, a process operator is often the first responder and takes measures to diminish the effects of an incident. Thus, a process operator can be exposed to dangerous circumstances, and therefore personal protective equipment has to be worn. In case of fire, the operator may be exposed to high heat radiation levels. Previous studies have established maximum acceptable heat radiation levels for long- (>15 min) and short-term exposures (<5 min), these being 1.0 kW/m2 and 1.5 kW/m2, respectively. These limits were based on manikin measurements and physiological models. The validation of the protection of operators' clothing in human trials is lacking. Therefore, twelve professional firefighters were exposed to three different heat radiation levels in process operators' clothing. The experiments showed that the majority of the operators can be exposed for 5 min to 1.5 kW/m2, up to 3 min to 2.0 kW/m2, while exposure to 2.5 kW/m2 or above must be avoided. Due to a slower skin temperature rise, loose-fitting protective clothing was related to longer exposure times. We speculate that additional long-armed/legged (under)clothing may offer more protection and extend the exposure time to heat radiation. During the early stage of a fire, a process operator often acts as the first responder and may be exposed to high heat radiation levels. The present limit values of long- (>15 min) and short-term exposure (<5 min), 1.0 and 1.5 kW/m2, respectively, have been set using physiological models and manikin measurements. Since human validation is essentially lacking, this study investigated whether operators' protective clothing offers sufficient protection during a short-term deployment. Twelve professional firefighters were exposed to three radiation levels (1.5, 2.0, and 2.5 kW/m2) when wearing certified protective clothing in front of a heat radiation panel in a climatic chamber (20 °C; 50% RH). The participants wore only briefs (male) or panties and a bra (female) and a T-shirt under the operators' clothing. Skin temperatures were continuously measured at the chest, belly, forearm, thigh, and knee. The test persons had to stop if any skin temperature reached 43 °C, at their own request, or when 5 min of exposure was reached. The experiments showed that people in operators' clothing can be safely exposed for 5 min to 1.5 kW/m2, up to 3 min to 2.0 kW/m2, and exposure to 2.5 kW/m2 or above must be avoided unless the clothing can maintain an air gap. [ABSTRACT FROM AUTHOR]

Stability control of elements of stone constructions of various structures is a prerequisite for their safe operation. The use of modern methods of non-destructive diagnostics of the stress-strain state of such constructions is an effective, and in many cases the only way to control it. Studies of thermal radiation accompanying the processes of solid bodies deformation allowed to justify and develop a method that allows to obtain non-contact information about changes in the stress-strain state in various types of geomaterials, including limestones. However, studies of the water saturation influence of rocks on the thermal radiation parameters recorded in this way are currently superficial. Taking into account the water saturation degree of rocks is necessary when monitoring the mechanical condition of stone structures that are in direct contact with water. The main purpose of this work is to study the dependences of changes in the intensity of thermal radiation from the surface of limestone samples with different humidity under conditions of uniaxial compression. The obtained results showed the expected significant decrease in the mechanical properties (uniaxial compressive strength and elastic modulus) of water-saturated samples in comparison with dry ones. At the same time, a significant increase in the intensity of thermal radiation of limestone samples subjected to compression with an increase in their water saturation was recorded, which makes it necessary to take into account the revealed regularity when identifying changes in the stress state of stone structures established according to non-contact IR diagnostics in real conditions.

Heat treatment is a common operation in grain processing technology. Thermal action on grain is characterized by temperature level and duration. Also, the grain changes all its complex properties. Frequently, the temperature in grain activates the process of change in the moisture content and is accompanied by moisture loss. The processes of change in the heat and moisture are interrelated. Based on the experiments conducted on legumes (different varieties of bean, white lupin), a mathematical model of these processes has been developed and the appropriate non-linear differential equations have been used. The obtained equations cannot be solved either analytically or numerically, because some of the coefficients are unknown. The equations are solved based on certain assumptions. Based on these assumptions, the paper provides the calculation of the change in temperature and moisture content over time in legumes, such as bean and white lupin. The obtained results have been compared with experimental data.

In order to reflect the space-based full chain information of the detection process comprehensively and objectively, we proposed a novel modular evaluation metric to discuss the target, background, and system independently. It takes the equivalent radiation intensity as the parameter, which can evaluate the detection performance of the system quantitatively. In this paper, taking the fifth-generation American stealth fighter F22 as an example, the mathematical detection model of the space-based infrared system to aircraft targets in the Earth background is described. A modular evaluation metric is proposed. The simulation analyzes the impact of different detection scenes and system parameters on system equivalent irradiance. Furthermore, recommendations for the optimization of the detection system are given. The research results provide a new idea for the analysis of the detection performance of highly maneuverable targets under dynamic backgrounds and have guiding significance for the performance evaluation and parameter design of the infrared detection system. [ABSTRACT FROM AUTHOR]

The conditions of formation and properties of hybrid organic-inorganic composites based on epoxy polymer matrix and a mixture of magnetic and polymeric fillers are studied. Based on the study of physicochemical properties of fillers and composites, it was found that the introduction of a dispersion of magnetite modified with polymer shells and polyaniline doped with toluene sulfonic acid in the thermosetting epoxy composition in the amount of 2-6 wt.% provides the ability of composites to significant absorption and low reflection of IR and microwave range. It was found that the optimal content of the composition corresponds to the best mechanical properties of the obtained coatings, in particular, high microhardness. This makes it possible to use the proposed composition to obtain on its basis composite films and coatings for anti-radar purposes, which reduce the intensity of microwave radiation acting on the object and at the same time act as protective coatings on the surface of metals.

Background: Solar radiations are classified in terms of wavelengths, including visible light, infrared, and ultraviolet. Infrared radiation (IR) accounts the largest proportion of solar radiations that cause oxidative stress‐induced aging of human skin. This study investigates the biochemical changes in proteins, lipids, and DNA associated with acute exposure to IR radiations. Method: In vivo confocal Raman spectroscopy was used to examine the forearms region of 20 healthy participants with phototype II skin, aged between 18 and 30 years, without IR incidence (T0), with IR incidence 30 minutes (T30) at day 1 and 30 minutes at day 2 (T60). One‐way ANOVA and two‐tailed t test along with post hoc Bonferroni correction were used to detect the existence of significant differences in the timestamps of stratum corneum, stratum basale, and dermis at all IR wavenumbers under test. Results: An increase in the Raman peaks of stratum corneum lipids, decrease in stratum basal DNA peaks, and a shift in the amide I peak of collagen in the skin dermis were observed. One‐way ANOVA results showed significant differences among timestamps of stratum corneum, stratum basale, and dermis at all wavenumbers under test (P <.001). Furthermore, paired timestamps also showed significant differences (P <.016) except at two wavenumbers 1293 cm−1 and 852 cm−1 in stratum corneum and basale layer clusters on timestamps (T0 & T30 and T30 & T60, P >.016). This study proved that confocal Raman spectroscopy is an useful technique for early evaluation of IR‐induced skin changes. [ABSTRACT FROM AUTHOR]

A procedure is proposed for synthesizing monometallic (Co, Pd) and bimetallic Co–Pd nanoparticles immobilized in a carbon support based on pyrolyzed chitosan. A feature of the procedure is the simultaneous formation of metal nanoparticles and a carbon support during the heat treatment of a precursor based on a joint solution of a polymer and metal compounds under the effect of IR radiation. The phase composition, morphology of samples, and structural features of the carbon support are shown, depending on the nature of the metals that are used. [ABSTRACT FROM AUTHOR]

This article describes an experimental investigation into the heat fluxes generated by the combustion of AP/HTPB solid propellant samples inside 1‑MPa pressurized combustion chambers. Fluxmeters developed at ONERA and recently improved were used to measure the local heat flux densities. Two kind of fluxmeters were used: total fluxmeters for which the convective and the radiative components are measured and radiative fluxmeters for which the convective component is suppressed by the use of a sapphire window mounted on top of the fluxmeter. Additionally, the flame was visualized by a narrow-band filtered IR camera which provided quantitative and spatially resolved radiance field. From the IR camera recordings, a radiative heat flux equivalent to that measured by the radiative fluxmeters was constructed by means of the integration over the fluxmeters' collection volumes of the spectrally equivalent radiance. A satisfactory agreement is thus found between the two radiative heat flux measurement methods. [ABSTRACT FROM AUTHOR]

Metal-carbon nanocomposites, the structure of which is a carbon matrix with nanoparticles of a Fe–Co solid solution uniformly distributed in it, are synthesized by pyrolysis of a precursor based on chitosan and iron and cobalt nitrates under the action of infrared radiation in the temperature range 500–700°С. The features of the formation of nanoparticles of an Fe–Co solid solution are studied by X-ray diffraction depending on the synthesis conditions and the ratio of the metals in the system. The experimentally determined values of the lattice parameters are used to estimate the composition of the forming bimetallic Fe–Co nanoparticles. The morphology and dispersion of metal nanoparticles are studied by transmission electron microscopy. Elemental analysis of the samples under study is carried out by the methods of X-ray fluorescence analysis and X-ray photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

In this paper, a precise method for calculating albedo and IR heat flux applied to a satellite is presented. For obtaining albedo heat flux applied to a satellite, a point on the earth’s surface that sun flux reflected at that point and reach to the satellite is obtained, hence albedo heat flux reaches to a satellite is obtained as a function of longitude, attitude and longitude. IR heat flux is integration of emitting heat flux for points on the earth surface that in satellite’s view. Atmospheric transparency for calculating albedo and IR heat is considered for sun light and IR spectrum using MODTRAN algorithm using PcModWin software. For a generic LEO satellite, IR and albedo heat fluxes are calculated at a time period and compare with reference values. Obtained heat fluxes are used to obtain temperature variation of satellite’s components during its mission.

In this study, metal-carbon nanocomposites have been synthesized via the method of simultaneous formation of bimetallic Fe–Co nanoparticles and carbon support based on pyrolyzed chitosan under the IR irradiation. The XRD structural characteristics as well as morphology and dispersity of Fe–Co nanoparticles depending on the loading of metals in the nanocomposites have been studied. It has been shown that the increase in the metal salts loading in the precursor leads to the formation of metal nanoparticles of larger size and more homogeneous composition of the Fe–Co solid solution. Detailed analysis of the XRD peaks of the obtained Fe–Co phase has allowed to distinguish them into several phases of a solid solution based on body-centered cubic and face-centered cubic lattices. [ABSTRACT FROM AUTHOR]

An approach to the synthesis of metal-carbon nanocomposites, comprising iron-containing nanoparticles distributed in a highly porous carbon support based on pyrolyzed polyacrylonitrile, has been developed. It is shown that metal nanoparticles form in situ during pyrolysis of the polymer and the formation of a porous carbon matrix. Features of the formation of iron-containing particles are investigated, depending on the temperature of preliminary treatment (200, 500, and 800°C) and on the final temperature of synthesis, which varied from 500 to 900°C. The change in the specific surface area of the carbon support is shown, depending on the conditions of preparation. The formation of phases α-Fe, γ-Fe, and KFeO2 is observed in addition to that of iron carbide nanoparticles. [ABSTRACT FROM AUTHOR]

Heat treatment is a common operation in grain processing technology. Thermal action on grain is characterized by temperature level and duration. Also, the grain changes all its complex properties. Frequently, the temperature in grain activates the process of change in the moisture content and is accompanied by moisture loss. The processes of change in the heat and moisture are interrelated. Based on the experiments conducted on legumes (different varieties of bean, white lupin), a mathematical model of these processes has been developed and the appropriate non-linear differential equations have been used. The obtained equations cannot be solved either analytically or numerically, because some of the coefficients are unknown. The equations are solved based on certain assumptions. Based on these assumptions, the paper provides the calculation of the change in temperature and moisture content over time in legumes, such as bean and white lupin. The obtained results have been compared with experimental data. [ABSTRACT FROM AUTHOR]

Beneficiation of low rank lignite coals by wet cleaning methods is difficult and low efficiency. Low rank coals are broken into smaller particles in water and create too much slurry. Too much slurry is a problem and requires the construction of a large sludge pond. Clay minerals and other components in the texture of low rank coal also adsorb water. This creates various problems both during washing and in subsequent processes of washing. Especially dewatering and drying are an important cost element in coal preparation. Therefore, it is more rational to upgrade low rank coal with dry beneficiation techniques. Lignite coal which is net calorific value less than 2500 kcal/kg in Turkish coal market can not be sold. In this study, low rank coal with a lower calorific value 1650 kcal/kg was first treated with FGX dry separator and then dried with IR radiation to increase the net calorific value above 2500 kcal/kg. [ABSTRACT FROM AUTHOR]

The almost unexplored frequency window from submillimeter to mid-infrared (mid-IR) may bring new clues about the particle acceleration and transport processes and the atmospheric thermal response during solar flares. Because of its technical complexity and the special atmospheric environment needed, observations at these frequencies are very sparse. The High Altitude THz Solar Photometer (HATS) is a full-Sun ground-based telescope designed to observe the continuum from the submillimeter to the mid-IR. It has a 457-mm spherical mirror with the sensor in its primary focus. The sensor is a Golay cell with high sensitivity in a very wide frequency range. The telescope has a polar mount, and a custom-built data acquisition system based on a 32 ksamples per second, 24 bits (72 dB dynamic range), 8 channels analog-to-digital board. Changing only the composition of the low- and band-pass filters in front of the Golay cell, the telescope can be setup to detect very different frequency bands; making the instrument very versatile. In this article we describe the telescope characteristics and its development status. Moreover, we give estimates of the expected fluxes during flares. [ABSTRACT FROM AUTHOR]

Microfluidic devices have enormous potential and a wide range of applications. However, most applications end up as chip-in-a-lab systems because of power source constraints. This work focuses on reducing the reliance on the power network and expanding on the concept of a lab-on-a-chip for microfluidic devices. A cellulose-based radiator to reflect infrared (IR) radiation with wavelengths within the atmospheric window (8–13 µm) into outer space was fabricated. This process lowered the temperature inside the insulated environment. The difference in temperature was used to power a thermoelectric generator (TEG) and generate an electric current. This electric current was run through a DC-DC transformer to increase the voltage before being used to perform electrical cell lysis with a microfluidic device. This experimental setup successfully achieved 90% and 50% cell lysis efficiencies in ideal conditions and in field tests, respectively. This work demonstrated the possibility of utilizing the unique characteristics of a microfluidic device to perform an energy-intensive assay with minimal energy generated from a TEG and no initial power input for the system. The TEG system also required less maintenance than solar, wind, or hydroelectricity. The IR radiation process naturally allows for more dynamic working conditions for the entire system.

By the diffusion obtained the Si 〈B, P〉 (group I) and Si 〈B, P + Ni〉 (group II) structures with deep p–n-junctions. It is demonstrated that the parameters of silicon photovoltaic cells with deep p–n-junctions are improved due to nickel doping. After nickel diffusion, the average value of the open circuit voltage Voc of the photo cells to group I increases by 19.7%, and the short-circuit current density Jsc in-creases by 89%. It was established that the formation of nickel clusters occurs at the optimum temperature of thermal annealing T = 750–800°C. The relative increase in the efficiency of photovoltaic cells after ad-ditional thermal annealing at T = 800°C is 118.8%. In addition, in samples with a nickel-enriched area on the front side of the p–n-junction, the fill factor of the current–voltage characteristic increased by 30%. The influence of nickel atom clusters on the bulk properties of the base and the properties of the surface regions of the solar cell, where the concentration of nickel atoms is 2–2.5 orders of magnitude greater than in volume, is considered. It is proved that the nickel-rich n-layer near-surface region plays a significant role in increasing the efficiency of photovoltaic cells. Experimental results show that an increase in the lifetime of minority charge carriers leads to a sig-nificant increase in the solar cell collection factor. We associate the obtained data mainly with the getter properties of nickel atom clusters. We assume that doping with nickel clusters can increase the absorption coefficient of the base of the solar cell in the infrared region of the spectrum due to the appearance of plasmon resonance, which should lead to a better alignment of the absorption region of infrared light with the p–n-junction. [ABSTRACT FROM AUTHOR]

Breast cancer has been reported to be the first deadly disease that affects women worldwide. This type of cancer has been reported to be the second leading cause of death in women worldwide. Medical reports have also reported that every woman is exposed to having breast cancer with an average probability of about 12%. It has also been reported to be the most common cancer that affects women. Fatality could be due to the cancer detection delay; in other words, early detection of the tumor can increase the survival rate of patients. Routine techniques of imaging modalities for cancer screening such as Mammography, Computated Tomography (CT) scan, Magnetic Resonance Imaging (MRI) and ultrasound are impractical tools for many reasons such as the irreproducible nature, the high error rate in cases of thick breasts, the pain and the annoyance they cause. Consequently, there is a need for more convincing strategies with high accuracy rates in breast cancer detection. Therefore, among the large variety of medical breast scanning techniques, thermography has attracted attention in applications related to detection and diagnosis. It is capable of providing helpful and useful information about the physiological variations and accordingly, it can detect tumors even in early stages. In addition, it is a very safe scanning tool, so as many needed tests can be held in proper time and manner. Thermography relies on the fact that human body temperature generally is a natural norm for the diagnosis of diseases. Thermography in medical applications applies infrared body examination tool which is fast, noninvasive, noncontact, pain free, radiation free and flexible to monitor the temperature of the human body. The fundamental principle of thermography relies on physiology such as the distribution of temperature on the skin surface. Infrared thermography scanning for breasts is an imaging technique which essentially searches for temperature change in human body. Temperature variance could be considered as a good indicator of tumor occurrence in the scanned area. Tumor mainly causes a noteworthy increase in blood vessel circulation and metabolic activity, so it causes higher radiations emitted from the human body around the regions of tumor. The paper surveys the literature work conducted in the field of breast cancer detection from thermogram scans. The survey is followed by a discussion of the strengths and weaknesses of thermography-based tumor detection. A new research idea and some considerations are then suggested based on that discussion to achieve better results in this critical area. [ABSTRACT FROM AUTHOR]

Abstract The efficacy of Infra-red radiation (IR) and Pulsed UV (PUV) for the inactivation of parent (Par) and Nalidixic acid adapted (Nal) strains of Escherichia coli O157:H7, top six shiga-toxin producing E. coli (E. coli O26, E. coli O45, E. coli O103, E. coli O111, E. coli O121, and E. coli O145 and E. coli O104) along with nonpathogenic surrogates were evaluated. It was observed that significant (P < 0.05) differences in D values between E. coli O157 Par and non-O157 Par as well between the strains in the same serogroup when subjected to IR or PUV treatment. Individual nalidixic acid adapted strains and serogroups show varied levels of sensitivity towards IR and PUV. Calculated D values of parent strains except for E. coli O157:H7 strain E932 and E009 were significantly higher (P < 0.05) than the Nal strains when subjected to IR radiation. Strain 5 Par of E. coli O157:H7 was the most resistant among all the parent strains and serogroups when subjected to PUV treatment with a D value of 1.01 J/cm2 and serogroup E. coli O26 was the least resistant with a D value of 0.63 J/cm2. Nal counterparts of strains 4 and 5 of E. coli O157:H7 were significantly (P < 0.05) more sensitive to PUV than Par strains. Highlights • Significant difference in D values among different STEC strains when subjected to IR or PUV treatment. • D values of most STEC parent strains for IR treatment were significantly higher than the Nal strains. • It is important to validate Nal strains to a particular treatment before using for challenge studies. [ABSTRACT FROM AUTHOR]

Abstract A new procedure employing infrared radiation to produce a nitrogen-containing highly porous carbon material based on polyacrylonitrile has been developed. The carbon material with a specific surface area of 1986 m2 g−1 demonstrated a specific capacitance up to 210 F g−1, which can be attributed to an electrical double-layer capacitance of about 160 F g−1 combined with a pseudo-capacitance of about 50 F g−1 associated with the redox reactions of the nitrogen-containing surface groups. Graphical abstract Unlabelled Image Highlights • For the first time polyacrylonitrile-derived activated carbon was prepared under IR radiation. • Incoherent IR radiation provides a decrease of activation time down to a couple of minutes. • Electrochemical performance of the activated carbon was demonstrated. [ABSTRACT FROM AUTHOR]

The outgoing radiation spectra measured by the IRFS-2 spectrometer onboard Meteor-M no. 2 satellite have been analyzed. Some statistical parameters of more than 106 spectra measured in spring in 2015 have been calculated. The radiation brightness temperature varied from ~300 K (surface temperature) up to ~210 K (tropopause temperature). The quite high variability of the longwave measured radiation has been demonstrated. The signal-to-noise ratio distinctively decreases in the shortwave region (higher than 1300 cm-1). Intercomparisons of IR sounders IRFS-2 with IASI and CrIS spectra showed that the discrepancies in the average spectra and their variability do not exceed measurement errors in the spectral region 660-1300 cm-1. A comparison of specially chosen pairs of the simultaneously measured spectra showed that the differences between IRFS-2 and European instruments in the region of the 15-μm CO2 band and the transparency windows 8- 12 μm are less than 1 mW/(m2 sr cm-1) and no more than the differences between the two IASI instruments (-A and -B). The differences between measured and simulated spectra are less than 1 mW/(m2 sr cm-1) in the mean part of CO2 band. However, starting from 720 cm-1, values appear that reach 2-4 mW/(m2 sr cm-1). This is caused by the absence of precise information about the surface temperature. Further investigations into the possible reasons for the observed disagreements are required in order to improve both the method of initial processing and the radiative model of the atmosphere. [ABSTRACT FROM AUTHOR]

This paper examines the IR sensitization of PbSnSe films by heat treatment in air. The films were annealed in the temperature range from 403 to 723 K. Heat treatment was accompanied by the recrystallization of agglomerates in the films. The photosensitivity of the films was shown to depend on heat treatment temperature. The films sensitized in the temperature range 653-700 K offer the highest photosensitivity (80-140 μV). The observed increase in the dark resistance and voltage sensitivity of the films is probably due to the formation of oxide phases on the surface of their microcrystallites. [ABSTRACT FROM AUTHOR]

The features of detection of short radiation pulses by thermal detectors based on thin pyroelectric films with the radiation energy deposited in a thin absorbing electrode are considered. It is demonstrated that the minimum response time of the sample to radiation pulses is determined by the time of thermal relaxation of the absorbing electrode. Specifically, picosecond pulses may be detected with a 0.5-μm-thick pyroelectric film and a 0.01-μm-thick absorbing electrode. [ABSTRACT FROM AUTHOR]

Numerical simulation of infrared (IR) emission from aircraft is of great significance for military and civilian applications. In this paper, the narrow band k-distribution (NBK) model is used to calculate radiative properties of non-gray gases in the hot exhaust plume. With model parameters derived from the high resolution spectral database HITEMP 2010, the NBK model is validated by comparisons with exact line by line (LBL) results and experimental data. Based on the NBK model, a new finite volume and back ray tracing (FVBRT) method is proposed to solve the radiative transfer equations and produce IR imaging. Calculated results by the FVBRT method are compared with experimental data and available results in open references, which shows the FVBRT method can maintain good accuracy while producing IR images with better rendering effects. Finally, the NBK model and FVBRT method are integrated to calculate IR signature of an aircraft. The IR images and spatial distributions of radiative intensity are compared and analyzed in both 3 – 5 μ m band and 8 – 12 μ m band to provide references for engineering applications. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile (PAN) membranes with the rejection coefficients of bovine serum albumin ( M = 69000 Da) up to 97% have been developed. The effect of IR irradiation of PAN membranes at temperatures to 180°С has been studied for the first time. It has been found that the IR modification of the membranes at 120°С for 5 min makes PAN insoluble in a wide range of organic solvents. The test PAN membranes were obtained from PAN solutions in dimethyl sulfoxide (DMSO) with different polymer concentrations in casting solution. The morphology and filtration characteristics of the membranes are almost unaffected by the treatment. The permeability of the membranes to DMSO, dimethylformamide (DMF), dimethylacetamide (DMAA), and N-methyl-2-pyrrolidone (NMP) has been measured. It has been demonstrated that the IR-treated PAN membranes can be used for filtering the above solvents, although the initial polymer is soluble in these solvents. These membranes can also be used as supports of chemically resistant nanofiltration membranes for aprotic solvents. [ABSTRACT FROM AUTHOR]

High intensity optical radiation can cause damage to the eye and intense radiation in the range of 770-1400 nm can cause thermal retinal damage. In the workplaces where there are high temperature sources, the workers in front of these hot sources without bright light maybe exposed to the intense IR radiation, thus regular measurement of these radiations seems crucial. Measurement of IR radiations by radiometer in specific wavelength ranges is elusive. Moreover, when radiometers are used, the correct application of the recommended exposure limits requires knowledge of spectral radiance which seems sophisticated for hygienists. The main objective of the present study is applying a model to express retinal thermal injury in terms of temperature for molten aluminum ovens in an aluminum foundry that emit optical radiation without visible light. In the proposed model, ACGIH TLVs for retinal thermal injury in the range of 770 to 1400 nm was used where source luminance was under 0.01 cd/cm2. Also, by using the output results of this proposed model it is possible to present a new chart for evaluation of exposure to IR for hot sources based on Threshold Temperature.

In this work the procedure of replacing the inhomogeneous atmosphere with homogeneous layers is discussed. The absorption and emission functions of a layer in a selected spectral region are the same as they are for the inhomogeneous layer. The dependence of the effective brightness temperature of a layer on its thickness is shown in the methane absorption band 1220-1260 cm. Negative values of luminosity spectral density of a homogenous atmospheric layer with a width of over 3200 m indicate an increase in the weakening role of the layer for the outgoing radiation in the considered atmospheric model. The application of the method of gas optical filter correlation for a measurement of the methane content in the near-ground atmospheric layer from an aerospace platform is considered. [ABSTRACT FROM AUTHOR]

Temporal dynamics of peak intensity and power in a finite-size aperture of focused radiation at a wavelength of 10.6 µm under thermal self-action in a clear turbulent atmosphere is analyzed by means of computer simulation. Propagation of Gaussian beams along paths up to 160 m long is considered. It is shown that there are time spans where the peak intensity of a sharply focused beam in the middle of the path is higher than in the focal plane at the end of the path under strong fluctuations of the refractive index. [ABSTRACT FROM AUTHOR]

In this article we analyse the vibration excitation and following dissociation of protonated oligopeptide molecules induced by IR photons with λ=16-18 μm. The analysis is based on our previous works in which we considered a specific non-statistical dissociation process in organic molecules containing substructures consisting of chained identical diatomic dipoles such as (CH2)n. Such dipole chains can serve as IR antennas for external radiation in the IR frequency range. The acquired vibration energy accumulated in IR antennas can be large enough to dissociate molecules within a femtosecond time interval by a non-statistical process, which is driven by a radiationless low-energy transport mechanism inside the peptide molecules. We point out in this article that the suggested IR-induced dissociation mechanism can be applied to obtain sequence information of protonated oligopeptides. [ABSTRACT FROM AUTHOR]

High intensity optical radiation can cause damage to the eye and intense radiation in the range of 770-1400 nm can cause thermal retinal damage. In the workplaces where there are high temperature sources, the workers in front of these hot sources without bright light maybe exposed to the intense IR radiation, thus regular measurement of these radiations seems crucial. Measurement of IR radiations by radiometer in specific wavelength ranges is elusive. Moreover, when radiometers are used, the correct application of the recommended exposure limits requires knowledge of spectral radiance which seems sophisticated for hygienists. The main objective of the present study is applying a model to express retinal thermal injury in terms of temperature for molten aluminum ovens in an aluminum foundry that emit optical radiation without visible light. In the proposed model, ACGIH TLVs for retinal thermal injury in the range of 770 to 1400 nm was used where source luminance was under 0.01 cd/cm2. Also, by using the output results of this proposed model it is possible to present a new chart for evaluation of exposure to IR for hot sources based on Threshold Temperature. [ABSTRACT FROM AUTHOR]