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In the dairy industry, traditional heat treatments are known for their high water and energy consumption, and more economically and environmentally friendly solutions are being sought. Infrared (IR) technology offers advantages in energy efficiency and environmental sustainability; however, its effectiveness in milk processing, particularly in pathogen inactivation, remains relatively unexplored. In this study, homogenized raw milk was subjected to IR treatment, and its impact on Listeria monocytogenes, Salmonella spp., and Enterobacteriaceae was assessed. Results indicate that IR treatment effectively reduces the microbial load, achieving levels of inactivation comparable to conventional pasteurization methods (around 6 Log10 CFU/mL). Moreover, the treatment maintains milk pH levels, suggesting minimal alteration to its composition. Further research is needed to explore the full extent of IR treatment on milk sanitation efficacy, deeply exploring IR technology to fully assess its applicability and integration into dairy processing practices. Despite regulatory challenges, the Wir System Milk shows promise as a cost-effective and eco-friendly alternative for raw milk treatment. [ABSTRACT FROM AUTHOR]

Due to experimental challenges and computational complexities, limited research has explored high-temperature and high-pressure conditions on mineral vibrations. This study employs the quasi-harmonic approximation (QHA) and density functional theory (DFT) to investigate the impact of temperature and pressure on the structural properties and infrared and Raman vibrational modes of forsterite. The computational process involves determining lattice parameters, optimizing the internal crystal structure, and calculating IR and Raman spectra at various temperature and pressure values, both separately and combined. Results highlight significant anisotropy in forsterite, with the b-axis being most sensitive to temperature and pressure, followed by the c-axis, while the a-axis exhibits greater stiffness. The positions of vibrational modes typically shift to higher frequencies with increasing pressure (average shift of 2.70 ± 1.30 cm−1/GPa) or to lower frequencies with increasing temperature (average shift of − 0.017 ± 0.018 cm−1/K). Modes associated with SiO4 stretching and bending are less affected by temperature or pressure than translational and rotational modes. A brief investigation into isotope and chemical substitution, as well as cation distribution, in the solid solution (Mg, Fe)2SiO4 reveals lower wavenumbers in fayalite modes compared to forsterite modes, attributed to the heavier Fe mass and larger cell parameters. This study establishes a methodology for computing vibrational frequencies under simultaneous temperature and pressure and emphasizes the significant impact of various factors on vibrational modes. Caution is advised when using vibrational modes for identifying compositions within solid solutions. [ABSTRACT FROM AUTHOR]

Background and Objectives: Starch modification using heat‐moisture treatment (HMT) has been proven to influence starch functionality and nutritional properties as it can increase resistant starch content and reduce the glycemic index (GI). This study aims to determine the nutritional and functional properties of infrared (IR)‐ and microwave (MW) heat‐moisture‐treated (HMT) white and red non‐tannin, and red tannin sorghum meals with the aim of further reducing the estimated GI. Findings: All treated meals had significantly (p <.05) lower pasting peak viscosity than the untreated samples, possibly due to aggregate formation observed under the light microscope, restricting the starch from swelling to form a high‐viscosity paste. There was a decrease in the percentage of starch hydrolysis between the sorghum types and a further decrease after HMT treatment. A significant difference was observed in the protein digestibility between the sorghum types, but not between the treatments. Conclusion: HMT with IR and MW further reduced the starch digestibility, possibly because of changes in the starch molecular configuration. Significance and Novelty: This study suggests that the changes in the starch functionality and nutritional properties of the HMT‐treated sorghum meals can potentially be useful in the development of lower‐GI sorghum foods. The results also differentiate the characteristics of sorghum types. [ABSTRACT FROM AUTHOR]

Solid‐state infrared sources designed to emit wavelengths above 2 µm often face challenges in achieving high emission efficiency, minimizing power consumption, and reducing fabrication costs. In response, a 2.4 µm wavelength light emitting diode (LED) is developed using metamorphic In0.83Ga0.17As/InAs0.3P0.65Sb0.05 multiple quantum well (MQW) heterostructures. The substantial conduction (94 meV) and valence band offsets (300 meV) within this type‐I MQW LED architecture result in strong carrier confinement, improving electron and hole wavefunction overlap. Despite a notable lattice mismatch of 2.0% between the MQWs and InP substrate, the resulting LED wafer exhibits exceptionally low surface roughness (1.1 nm) and well‐defined, sharp interfaces within the heterostructures. Furthermore, this MQW LED exhibits favorable emission properties, including a low turn‐on field, minimal efficiency droop, and stable emission wavelength across varying injection currents. These advancements underscore the potential of such short‐wave infrared emitters for scalable applications in fields such as inspection, optical on‐chip communication, and biomedical diagnostics. [ABSTRACT FROM AUTHOR]

Oriented synthesis of functional materials is a focus of attention in material science. As one of the most important function materials, infrared nonlinear optical materials with large second harmonic generation effects and broad optical band gap are in urgent need. In this work, directed by the theoretical structure prediction, the first series of non‐centrosymmetric (NCS) alkali‐alkaline earth metal [PS4]‐based thiophosphates LiCaPS4 (Ama2), NaCaPS4 (P21), KCaPS4 (Pna21), RbCaPS4 (Pna21), CsCaPS4 (Pna21) were successfully synthesized. Comprehensive characterizations reveal that ACaPS4 could be regarded as promising IR NLO materials, exhibiting wide band gap (3.77–3.86 eV), moderate birefringence (0.027–0.064 at 1064 nm), high laser‐induced damage threshold (LIDT, ~10×AGS), and suitable phase‐matching second harmonic generation responses (0.4–0.6×AGS). Structure‐properties analyses illustrate that the Ca−S bonds show non‐ignorable covalent feature, and [PS4] together with [CaSn] units play dominant roles to determine the band gap and SHG response. This work indicates that Li‐, Na‐ and K‐ analogs may be promising infrared nonlinear optical material candidates, and this is the first successful case of "prediction to synthesis" involving infrared (IR) nonlinear optical (NLO) crystals in the thiophosphate system and may provide a new avenue to the design and oriented synthesis of high‐performance function materials in the future. [ABSTRACT FROM AUTHOR]

The regulation of infrared (IR) thermal radiation has received widespread attention; the proposals have been made for various devices that use electrochromic materials. However, the visible appearance of the mentioned devices also changes when the IR states are altered. Herein, the memristive mechanism is utilized to regulate IR emissivity and design a novel transparent memristor‐type modulator featuring an Indium tin oxide (ITO)/HfO2/ITO structure. The modulator exhibits a dynamic emissivity variation of 0.38 in the IR region of 2.5–25 μm, without compromising transparency in the visible region under the application of an electric voltage. The migration of oxygen vacancies results in the modification of interface barriers and the formation of oxygen vacancy‐enriched regions, thereby enabling the modulator to exhibit resistive switching behavior and regulate IR emissivity. An array of modulators is also assembled, demonstrating the ability to independently display visible and IR information. In this work, new possibilities are presented for various applications such as multispectral displays, energy‐efficient thermoregulation, encrypted information displays, and camouflage. [ABSTRACT FROM AUTHOR]

Bacteriophages are emerging as a promising alternative in combating antibiotic-resistant bacteria amidst the escalating global antimicrobial resistance crisis. Recently, there has been a notable resurgence of interest in phages, prompting extensive research into their therapeutic potential. Beyond conventional microbiology and virology techniques, such as genomics and proteomics, novel phenotypic and chemical characterization methods are being explored. Among these, there is a growing interest in vibrational spectroscopy, especially in advanced modalities such as surface-enhanced Raman spectroscopy (SERS), tip-enhanced Raman spectroscopy (TERS), and atomic force microscopy-infrared spectroscopy (AFM-IR), which offer improved sensitivity and spatial resolution. This review explores the spectrum of uses of vibrational spectroscopy for bacteriophages, including its role in diagnostics, biosensing, phage detection, assistance in phage-based therapy, and advancing basic research. [ABSTRACT FROM AUTHOR]

Three dimensional Not-And (3D NAND) flash memory devices are scaling in the vertical direction to more than 200 oxide/sacrificial wordline nitride layers to further increase storage capacity and enhance energy efficiency. The accurate measurement of the thicknesses of these layers is critical to controlling stress-induced wafer warping and pattern distortion. While traditional optical metrology in the UV-vis-NIR range offers a non-destructive inline solution for high volume manufacturing, we demonstrate in this paper, that mid-IR metrology has advantages in de-correlating oxide and nitride thicknesses owing to their unique absorption signatures. Furthermore, because of the depths sensitivity of oxide and nitride absorptions, the simulated measurement results show the ability to differentiate thickness variations in the vertical zones. Good blind test results were obtained with a machine learning model trained on pseudo-references and pseudo spectra with added skew. [ABSTRACT FROM AUTHOR]

Spectral features of olivine across the intermediate infrared region (IMIR, 4–8 μm) shift systematically with iron‐magnesium content, enabling determination of olivine composition. Previous IMIR studies have used laboratory data with signal‐to‐noise ratios (SNRs) and spectral resolutions potentially greater than those of data derived from planetary missions. Here we employ a feature fitting algorithm to quantitatively assess the influence of data quality on olivine detection and compositional interpretation from IMIR data of 29 spectra of pure olivine of synthetic, terrestrial, lunar, and Martian origins, as well as 5 spectra of lunar pyroclastic beads measured as bulk samples. First, we demonstrate the effectiveness of the feature fitting algorithm in the interpretation of IMIR olivine spectra, predicting olivine composition with an average error of 6.4 mol% forsterite across all test spectra using laboratory‐quality data. We then extend this analysis to degraded test spectra with reduced SNRs and sampling rates and find a range of data qualities required to predict olivine composition within ±11 Mg# (molar Mg/[Mg + Fe] × 100) for the test spectra explored here. Spectra for the sample most relevant to lunar exploration, an Apollo 74002 drive tube consisting of microcrystalline olivine and glass‐rich pyroclastics, required SNRs ≥ 200 for sampling rates ≤25 nm to predict composition within ±11 Mg# of the sample's true composition. Derived limits on SNRs and sampling rates will serve as valuable inputs for the development of IMIR spectrometers, enabling comprehensive knowledge of olivine composition on the lunar surface. Plain Language Summary: An understanding of olivine composition can reveal the history of large‐ and small‐scale magmatic processes, offering key insights into a planet's thermal and chemical evolution. Here we explore olivine spectra in the intermediate infrared region (IMIR), where systematic trends in olivine's absorption bands are indicative of composition. We degrade laboratory olivine spectra to data qualities that are more realistic of spectrometers used in planetary exploration and derive constraints on the signal‐to‐noise ratio and sampling rates required to accurately predict olivine composition. These constraints will be useful in the development of IMIR spectrometers. Key Points: We use a feature fitting routine to predict olivine composition from degraded spectral data in the intermediate infrared region (4–8 μm)Accurate prediction of olivine composition is observed at data qualities expected of spectrometers designed for space exploration [ABSTRACT FROM AUTHOR]

We exploit the DustPedia sample of galaxies within approximately 40 Mpc, selecting 388 sources, to investigate the correlations between IR luminosity (LIR), the star formation rate (SFR), and the CO(1-0) luminosity (LCO) down to much lower luminosities than reached by previous analyses. We find a sub-linear dependence of the SFR on LIR. Below log (L IR / L ⊙) ≃ 10 or SFR ≃ 1 M ⊙ yr − 1 , the SFR/LIR ratio substantially exceeds the standard ratio for dust-enshrouded star formation, and the difference increases with decreasing LIR values. This implies that the effect of unobscured star formation overcomes that of dust heating by old stars, at variance with results based on the Planck ERCSC galaxy sample. We also find that the relations between the LCO and LIR or the SFR are consistent with those obtained at much higher luminosities. [ABSTRACT FROM AUTHOR]

To address the issues of incomplete information, blurred details, loss of details, and insufficient contrast in infrared and visible image fusion, an image fusion algorithm based on a convolutional autoencoder is proposed. The region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map. A multi-scale convolution attention module is suggested to enhance the communication of feature information. At the same time, the feature transformation module is introduced to learn more robust feature representations, aiming to preserve the integrity of image information. This study uses three available datasets from TNO, FLIR, and NIR to perform thorough quantitative and qualitative trials with five additional algorithms. The methods are assessed based on four indicators: information entropy (EN), standard deviation (SD), spatial frequency (SF), and average gradient (AG). Object detection experiments were done on the M3FD dataset to further verify the algorithm's performance in comparison with five other algorithms. The algorithm's accuracy was evaluated using the mean average precision at a threshold of 0.5 (mAP@0.5) index. Comprehensive experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks. [ABSTRACT FROM AUTHOR]

Triglycine sulfate (TGS) crystals are pyroelectric crystals that exhibit ferroelectricity in a room-temperature environment. They have application as infrared detector elements. In this study, it was found that irradiation with 40-GHz electromagnetic waves accelerates the growth of TGS crystals, with a growth rate about 2.2 times faster than that without irradiation. This leads to a reduction in process time and therefore crystals that will be used as elements in the production of detectors can be obtained more quickly. The TGS crystals were irradiated with a CO2 laser at a wavelength of 10.6 μm. The maximum voltage value obtained was about 0.24 V, the photosensitivity was 24.7 V/W, and the noise equivalent power (NEP) was 2.7 × 10−8 W/Hz½. In addition, it was confirmed that the sensitivity increased with decreasing area of the crystal. These results show that TGS crystals grown under electromagnetic irradiation can be used as infrared detector elements. [ABSTRACT FROM AUTHOR]

In this work, a new two‐step process is developed by exchanging Na+ and Ag+ to create a radial GRIN infrared lens. The first step consists in introducing a high amount of silver by solid‐state ion exchange in the surrounding of the glass sample when the second one allows for controllable diffusion of Ag+ within the center of the sample by single heat treatment. Evolution of the refractive index and ∆n between the two extreme compositions of the GRIN are determined as function of the wavelength, predicting a ∆n of 1.42 × 10−1 at 10 µm. Qualitative characterization of the sample reveals the formation of a GRIN chalcogenide glass transparent in the MWIR and LWIR, presenting no detrimental crystallization of residual metallic silver on the edge of the sample. Wavefront measurement allows to quantitatively characterize the 10 mm diameter IR GRIN as a polynomial profile with a ∆n of 1.8 × 10−1 at 10.6 µm. [ABSTRACT FROM AUTHOR]

Among materials produced as colloidal quantum dots (CQDs), HgTe has a special status being the only material covering the whole infrared range from the visible to the THz (0.7–100 µm). This unique property resulting from its electronic structure, combined with an air stability and a capacity for charge conduction has generated consistent and massive efforts to produce and improve HgTe CQDs over the past two decades. Meanwhile, HgTe CQDs offer an infrared platform more advanced than any other colloidal alternatives in the mid‐wave infrared regarding their integration into advanced photonic and optoelectronic applications. Here, the latest developments of HgTe CQDs relative to the material's growth, electron structure modelling, its integration into photonic structures and its transfer as the active material from single element devices toward complex sensors and infrared imagers are reviewed. Finally, a discussion about the potential of this material for industry, rising new challenges beyond economical and production considerations at low technological readiness level, relative to the material and device design, is also included. [ABSTRACT FROM AUTHOR]

The effect of La, Ce, Pr and Nd ions on four Ln(ligand)3 complexes and at three DFT levels of calculation was analyzed. Four ligands were chosen, three of which were based on the 1,2,3-triazole ring. The DFT methods used were B3LYP, CAM-B3LYP and M06-2X. The relationships established were between the geometric parameters, atomic charges, HOMO-LUMO energies and other molecular properties. These comparisons and trends will facilitate the synthesis of new complexes by selecting the ligand and lanthanide ion best suited to the desired property of the complex. The experimental IR and Raman spectra of Ln(2b′)3 complexes where Ln = La, Ce, Pr, Nd, Sm, Gd, Dy, Ho and Er ions have been recorded and compared to know the effect of the lanthanide ion on the complex. The hydration in these complexes was also analyzed. Additionally, the effect of the type of coordination center on the ability of an Ln(ligand)3 complex to participate in electron exchange and hydrogen transfer was investigated using two in vitro model systems—DPPH and ABTS. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations were performed to examine the impact of exchange–correlation (XC) functionals and van der Waals corrections (specifically the D3 method) on the structural and vibrational properties of the SrCl2–NaCl and ZrF4–LiF salt systems. Multiple XC functionals, including the local density approximation (LDA), the generalized gradient approximation using the Perdew–Burke–Ernzerhof (PBE) model, and its modified form suitable for solids (PBEsol), the dispersion‐corrected PBE‐D3 and PBEsol‐D3, were considered. Of these functionals, LDA was found to exhibit the highest degree of error, while PBEsol and PBE‐D3 displayed the least error. Underestimated lattice parameters compared with experimental values were observed to result in higher force constants, leading to an overprediction of vibrational frequencies. Conversely, an overestimation of lattice parameters was associated with lower vibrational frequencies. The methodology presented in this study yielded results that are in good agreement with experiment, irrespective of the method (finite differences vs. density functional perturbation theory) employed for calculating infrared and Raman spectra. It was further demonstrated that for alkali halides with weak Raman scattering, utilizing a supercell constructed from primitive cells better predicts Raman features than does the use of conventional cells. [ABSTRACT FROM AUTHOR]

For monitoring hard-to-reach thermal facilities, remote surveillance techniques from unmanned aerial vehicles (UAVs) equipped with a thermal infrared camera represent a progressive platform for rapid information collection. This paper presents the first results of such an application of UAVs to study five thermal objects on the Kuril Islands. Four of them (Kipyashchaya Riwer on Iturup Island, Lake Biryuzovoye on Simushir Island, Yankich Island and Yurieva River on Paramushir Island) are associated with active volcanoes. Heat maps with precise geographical reference have been obtained for all sections of gas hydrothermal discharge. For Kipyashchaya River and Yankich Island verification of air thermometry by ground data was performed and real atmospheric attenuation coefficients were obtained for different flight altitudes under observed meteorological conditions. The first data on the parameters of the thermal plume from the hot Yurievа River flowing into the Sea of Okhotsk were obtained.

The well-known Rule07 is a simple thus efficient way to compare available technologies for IR imaging detectors in terms of dark current. The noise is then often estimated using a shot noise approximation on the dark current. Both II–VI and III–V communities use this rule of thumb as a reference for well-performing IR photodiodes. For HOT applications, a dark current close to this rule07 is considered a necessary condition but not a sufficient one to obtain a high-performance IR imager. Indeed, when limited by shot noise, rule07 describes well the noise behavior of the considered device. However, when considering low-frequency noise, it fails to describe the expected performances. In this paper, we focus on another figure-of-merit, dedicated to detector low-frequency noise rather than dark current. Systemic 1/f noise investigation in an IR detector was first reported by Tobin et al. in 1980. There is today a relative consensus on the fact that measured 1/f noise is proportional to the dark current. The ratio between the amplitude of the 1/f noise and the dark current of the same devices may therefore be used as a figure-of-merit for a given technology. This ratio (called the Tobin factor α T ) therefore appears adequate to compare different technologies as a figure-of-merit qualifying 1/f noise properties. This dimensionless ratio can also be very useful for optimizing a particular technology or process. However, in order to be relevant, this figure-of-merit must be estimated carefully as it appears, for instance, pixel pitch-dependent. Different examples of Tobin coefficient extraction are presented in this paper. We show that, depending on the technologies, the values of the Tobin coefficient can spread over several orders of magnitude. However, only low values result in high-quality IR imagers. Today, the best results we obtained show that α T = 10 - 5 is a state-of-art value to be compared with. [ABSTRACT FROM AUTHOR]

Contact resistance can play a significant role in the noise performance of short wavelength infrared (SWIR) focal plane detector arrays (FPAs), particularly during cryogenic operation at low signal backgrounds. For astronomy FPAs, a source follower input cell ROIC is typically used in combination with correlated double sampling (CDS) or a form of up-the-ramp (SUTR) multi-sampling. In this paper, a pixel equivalent circuit model is presented and analyzed by standard techniques. The noise power density spectrum is analyzed for CDS and multi-sampled acquisitions, and it is found that there are three distinct ranges of contact resistance that govern excess noise behavior: the low-noise ROIC-limited range, the intermediate kTC-limited range, and the RC-bandwidth limited case. The model analyses are used to explain FPA data from Teledyne H2RG and H4RG SWIR FPAs. We have found that sampling sequence in combination with contact resistance can influence the total integrated noise, and can explain a FPA failure mode where anomalously low CDS and anomalously high SUTR noise exist in the same region. [ABSTRACT FROM AUTHOR]

Pulse Detonation Engine has been a point of interest in the propulsion industry for some time and the interest has been rising due to its better output and results. But any system can perform its task efficiently based on the efficiency of its control system. In this paper we have presented a comparative study between multiple control systems- one based on Bluetooth technology, the other based on infrared sensor technology and one based on wired electrical system. For the wireless system, the signal received from either of the media is passed to the various sensors and systems connected through an Arduino board that further controls the solenoid valves and ignition system. Primarily, a control system circuit is developed using Arduino board and different sensors to connect the fuel supply and ignition system. In the next stage, Bluetooth sensors are connected using an android app and then an infrared sensor based system is integrated with the Arduino to control the engine and the performance of the two systems are compared. Whereas for wired system, every sub system is controlled through optical wires including the solenoid valves, the injection system and the sensors.

ABSTRACT: Roasting is the most common processing method that enhances color, and texture. In this study, infrared roasting of peanuts was done using an infrared rotary dryer. Roasting was operated at 90% infrared power (630 W) with different rotating speed (1 and 2 r/min). The effect of roasting was studied at different moisture levels (7.66%, 11.49%, and 13.72% db). From the study, the color parameter, L* value, was found to be significantly different (P < 0.05), and it decreased with the decrease in rotating speed, and the ∆E value varies from 2.32 to 10.56. Results also showed that the antioxidant activity decreased with the reduction in rotating speed as lesser revolutions took longer roasting time, and the values decreased from 84.34% to 71.74%. Minimal changes in total phenolic content were found and varied from 3.62 to 2.10 mg/g GAE, an appropriate limit for good-quality roasted peanuts. The hardness of roasted peanuts ranged from 12.25 to 39.43 N. Moisture content 13.72%, and 1 r/min is the best possible treatment for infrared peanut roasting, significantly enhancing the quality of peanuts. This study concluded that high-power short-time infrared roasting could give good-quality roasted peanuts with optimum bioactive compounds.

The effects of infrared baking and microwave baking on the quality of pork tenderloin was compared by using sensory evaluation, texture, malondialdehyde, peroxide value, protein, volatile flavor substances as examination factors. The results showed that, there was no significant difference in the effect of two roasting methods on the color of pork (P>0.05). Infrared roasted pork had an average sensory score of 3.67 points higher than microwave roasted pork, but had lower hardness and chewiness. The content of malondialdehyde and peroxide value of infrared roasted pork were 16.89% and 38.36% higher than those of microwave roasted pork, respectively. The active sulfhydryl content in infrared roasted pork was significantly lower than that in microwave roasted pork (P

Infrared (IR) luminosity of lightning channel in the 3–5 μm range usually persisted throughout the entire interstroke interval, which is in contrast to the simultaneously recorded visible (0.4–0.8 μm) luminosity that always decayed to an undetectable level prior to a subsequent return stroke pulse. A longer visible luminosity period at the end of flash tended to be associated with a longer IR afterglow period following the decay of visible luminosity (and by inference current) to an undetectable level. At the end of flash, the IR luminosity persisted up to about 1 s, and the median IR afterglow duration was a factor of 10 longer than the median visible luminosity duration. The IR luminosity often exhibited a hump when the visible luminosity was monotonically decaying or undetectable, with the corresponding channel temperature being likely around 3400 K. Plain Language Summary: Lightning is usually imaged in the visible (0.4–0.8 μm) range, although it also produces significant infrared (IR) emission. In this study, we compare, for the first time, the medium‐to‐far (3–5 μm) IR luminosity of lightning channels with the simultaneously recorded visible luminosity. The key findings include the persistent nature of IR luminosity throughout interstroke intervals, which is in contrast to visible luminosity that always decayed to an undetectable level before the following return‐stroke onset. After the last stroke, IR luminosity persisted much longer than visible luminosity. The IR luminosity often exhibited a hump when visible luminosity was monotonically decreasing or already undetectable. We inferred that the IR hump, occurring when the channel temperature decreases to a few thousand Kelvin, is associated with enhanced IR emission from nitric oxide molecules whose concentration is expected to be maximum around 3400 K. We also examined a number of factors influencing IR afterglow duration, such as the number of preceding strokes, return‐stroke peak current, and the occurrence of M‐components. This study contributes to the very limited literature on the IR emission from lightning and provides new insights into the dynamics of lightning channel cooling process. Key Points: In contrast to the visible, infrared (IR) channel luminosity between strokes usually persisted through the following return‐stroke onsetIR luminosity profile often exhibited an increase (hump) when the visible luminosity was monotonically decaying or undetectableAt the end of flash, IR luminosity persisted up to ∼1 s and its median duration was a factor of 10 longer than its visible counterpart [ABSTRACT FROM AUTHOR]

The process of sprouting makes legumes better by changing their nutrition, chemicals, and taste. Ground sprouted chickpeas are commonly used as the main ingredient in falafel. The aim of this research was to study the impact of drying techniques that include hot‐air, infrared, and microwave on the moisture, ash, total phenolics, antioxidant capacity, color, and rehydration ratio of dried ground sprouted chickpeas. Also, the effects of drying techniques of ground sprouted chickpeas on the moisture, ash, total phenolics, antioxidant activity, color, volume, density, oil content, textural properties, and sensory attributes of fried falafel were examined. The total phenolics of hot‐air‐dried, infrared‐dried, and microwave‐dried samples were 463.42, 766.20, and 470.82 μg Gallic acid (GA)/g dry, respectively. The infrared‐dried ground sprouts had the highest antioxidant capacity. Additionally, the total phenolic content and antioxidant capacity of fried falafels made from infrared‐dried ground sprouted chickpeas were significantly higher than those of the fried falafels made from hot‐air‐dried and microwave‐dried sprouts (p < .05). The mean values of lightness, redness, and yellowness of the fried falafel core ranged from 57.37 to 59.29, 3.66 to 6.88, and 40.50 to 43.31, respectively. The lowest oil absorption was related to the sample prepared from the hot‐air‐dried sprouted chickpeas (p < .05). The firmness, cohesiveness, springiness, and chewiness of the fried falafels were between 38.17 N and 91.56 N, 0.29 and 0.44, 0.48 and 0.58, and 5.38 N and 17.24 N, respectively. The use of infrared‐dried sprouted chickpeas for producing fried falafel, due to the highest odor, flavor, and overall acceptance scores, high phenolic compounds and antioxidant activity, high volume, low density, and low hardness, is recommended. [ABSTRACT FROM AUTHOR]

In the autonomous driving industry, there is a growing trend to employ long-wave infrared (LWIR)-based uncooled thermal-imaging cameras, capable of robustly collecting data even in extreme environments. Consequently, both industry and academia are actively researching contrast-enhancement techniques to improve the quality of LWIR-based thermal-imaging cameras. However, most research results only showcase experimental outcomes using mass-produced products that already incorporate contrast-enhancement techniques. Put differently, there is a lack of experimental data on contrast enhancement post-non-uniformity (NUC) and temperature compensation (TC) processes, which generate the images seen in the final products. To bridge this gap, we propose a histogram equalization (HE)-based contrast enhancement method that incorporates a region-based clipping technique. Furthermore, we present experimental results on the images obtained after applying NUC and TC processes. We simultaneously conducted visual and qualitative performance evaluations on images acquired after NUC and TC processes. In the visual evaluation, it was confirmed that the proposed method improves image clarity and contrast ratio compared to conventional HE-based methods, even in challenging driving scenarios such as tunnels. In the qualitative evaluation, the proposed method demonstrated upper-middle-class rankings in both image quality and processing speed metrics. Therefore, our proposed method proves to be effective for the essential contrast enhancement process in LWIR-based uncooled thermal-imaging cameras intended for autonomous driving platforms. [ABSTRACT FROM AUTHOR]

Rapid and minimally destructive methods for estimating the endogenous organic content of subfossil bone save time, lab consumables, and valuable ancient materials. Fourier transform infrared (FTIR) spectroscopy is an established method to estimate bone protein content, and portable spectroscopes enable field applications. We review the ability of benchtop and portable FTIR indices to predict %N and %collagen from 137 bone specimens drawn from eight taxa. We also explore associations of these indices with the endogenous DNA content estimated for 105 specimens. Bulk bone elemental abundance and crystallinity index data reflect diagenetic alteration of these specimens, which come from a variety of depositional environments in four countries (Madagascar, Greece, Monaco, and Germany). Infrared (IR) indices from benchtop and portable units perform similarly well in predicting observed sample N content and collagen yields. Samples that include little collagen (0–5 wt%) tend to have similar IR index values, and we present a Bayesian approach for the prediction of collagen yields. Bone type best explains variation in target species DNA content (endogenous DNA being particularly abundant in petrosals), but low IR index values were consistently associated with minimal DNA content. We conclude that, although portable FTIR fails to distinguish collagen preservation among poorly preserved samples, a simple approach with minimal sample preparation can effectively screen bone from a variety of taxa, elements, and environments for the extraction of organics. [ABSTRACT FROM AUTHOR]

Background: This study used infrared thermography (IRT) for mapping the facial and ocular temperatures of howler monkeys, to determine parameters for the diagnosis of febrile processes. There are no published IRT study in this species. Methods: Were evaluated images of a group of monkeys kept under human care at Sorocaba Zoo (São Paulo, Brazil). The images were recorded during 1 year, in all seasons. Face and eye temperatures were evaluated. Results: There are statistically significant differences in face and eye temperatures. Mean values and standard deviations for facial and ocular temperature were respectively: 33.0°C (2.1) and 36.5°C (1.9) in the summer; 31.5°C (4.5) and 35.3°C (3.6) in the autumn; 30.0°C (4.3) and 35.6°C (3.9) in the winter; 30.8°C (2.9) and 35.5°C (2.1) in the spring. Conclusions: The IRT was effective to establish a parameter for facial and ocular temperatures of black‐and‐gold howler monkeys kept under human care. [ABSTRACT FROM AUTHOR]

The sprouting process includes changes in nutritional, biochemical, and sensory characteristics that improve chickpea quality and increase its digestibility. Various products such as Falafel are made from ground and dried chickpea sprouts. Therefore, in this research, the use of hot air (70°C), infrared (250 W), and microwave (220 W) methods for drying ground chickpea sprouts was investigated and modeled. The drying time of the samples in the infrared dryer was shorter than the other two dryers. The average drying time of the samples in the hot air, infrared and microwave dryers was 63.3, 26.7, and 156.7 min, respectively. In this research, the effective moisture diffusivity coefficient of ground chickpea sprouts in hot air, infrared and microwave dryers was determined to be 4.99×10-9 m² s -1, 17.95×10-9 m² s -1, and 1.59×10-9 m² s -1, respectively. To study the drying kinetics of ground chickpea sprouts, Wang and Singh, Henderson and Pabis, Approximation of diffusion, Page, Newton, Midilli, and Logarithmic mathematical models were fitted to the experimental data. Finally, when modeling the drying process of this product, Midilli's mathematical model with four parameters was chosen as the best model due to its minimal error. [ABSTRACT FROM AUTHOR]

Soil acidification is an issue for agriculture that requires effective management, typically in the form of lime (calcium carbonate, CaCO3), application. Mid infrared (MIR) spectroscopy methods offer an alternative to conventional laboratory methods, that may enable cost-effective and improved measurement of soil acidity and responses to liming, including detection of small–scale heterogeneity through the profile. Properties of an acidic soil following lime application were measured using both MIR spectroscopy with Partial Least Squares Regression (MIR-PLSR) and laboratory measurements to (a) compare the ability of each method to detect lime treatment effects on acidic soil, and (b) assess effects of the different treatments on selected soil properties. Soil properties including soil pH (in H2O and CaCl2), Aluminium (Al, exchangeable and extractable), cation exchange capacity (CEC) and organic carbon (OC) were measured at a single field trial receiving lime treatments differing in rate, source and incorporation. Model performance of MIR-PLSR prediction of the soil properties ranged from R2 = 0.582, RMSE = 2.023, RPIQ = 2.921 for Al (extractable) to R2 = 0.881, RMSE = 0.192, RPIQ = 5.729 for OC. MIR-PLSR predictions for pH (in H2O and CaCl2) were R2 = 0.739, RMSE = 0.287, RPIQ = 2.230 and R2 = 0.788, RMSE = 0.311, RPIQ = 1.897 respectively, and could detect a similar treatment effect compared to laboratory measurements. Treatment effects were not detected for MIR-PLSR-predicted values of CEC and both exchangeable and extractable Al. Findings support MIR-PLSR as a method of measuring soil pH to monitor effects of liming treatments on acidic soil to help inform precision agricultural management strategies, but suggests that some nuance and important information about treatment effects of lime on CEC and Al may be lost. Improvements to prediction model performance should be made to realise the full potential of this approach. [ABSTRACT FROM AUTHOR]

The Europa Thermal Emission Imaging System (E-THEMIS) on the Europa Clipper spacecraft will investigate the temperature and physical properties of Europa using thermal infrared (TIR) images in three wavelength bands centered from 7-14 μm, 14-28 μm and 28-80 μm. E-THEMIS will map >80% of the surface Europa at multiple times of day at a resolution of 8-km per pixel, ∼32% percent of the surface at ≤1 km/pixel resolution, and ∼6% percent at ≤100 m/pixel resolution. The specific objectives of the investigation are to 1) understand the formation of surface features, including sites of recent or current geologic activity, in order to understand regional and global processes and evolution and 2) to identify safe sites for future landed missions. E-THEMIS uses an uncooled microbolometer detector array for the IR focal plane. The E-THEMIS focal plane has 920 cross-track pixels (896 active) and 140 along-track pixels in each of the three spectral bands. The image data are collected at 14-bits per pixel at a frame rate of 60 Hz. The instrument can operate in framing mode, where full frame images are collected, and optionally co-added in time, in each band, or in time-delay-integration (TDI) mode where consecutive rows from each band are offset spatially to remove the spacecraft motion and then summed. In addition, the data in each band can be spatially aggregated from 2 × 2 to 5 × 5 pixels. These modes will be varied throughout each Europa flyby to optimize the data precision while fitting within the E-THEMIS data allocation. The expected temperature precision, measured as the noise equivalent spectral radiance, is 1.2 K at scene temperatures ≥90 K for a TDI of 16 with 4 × 4 pixel coaggregation in Band 2. The absolute accuracy at 90 K is 2−3 K in Band 2. E-THEMIS is an all-reflective, three-mirror anastigmat telescope with a 6.45-cm effective aperture and a speed of f/1.34 cross-track and 1.92 along-track. The mass of instrument Sensor Assembly, mounted on the spacecraft nadir deck, is 11.4 kg, the vault electronics are 1.8 kg, and the two are connected through a 3.1 kg harness. The Sensor volume is 23.7 cm x 31.8 cm x 29.8 cm. E-THEMIS consumes an average operation power of 34.8 W at 28 V. E-THEMIS was developed by Arizona State University with Raytheon Vision Systems developing the microbolometer focal plane assembly and Ball Aerospace developing the electronics. E-THEMIS was integrated, tested, and radiometrically calibrated on the Arizona State University campus in Tempe, AZ. [ABSTRACT FROM AUTHOR]

In this study, we innovatively propose salience-combined map and gradientlet filter for infrared and visible image fusion. It can enhance the infrared image of the target and also retain more detailed textures. First, our method is based on a multi-scale decomposition framework and gradientlet filter to decompose the source graph into approximate layers and residual layers. The approximate layers preserve smooth areas of the source images without edge blurring. The residual layers reflect the small gradients and noise of the source image. Since the texture part of the residual layer is weak, we introduce a Gamma-enhanced gradient map to complement the texture. The initial fusion image can be obtained by fusing the approximate layers and the residual layers. The salience-combined map directly extracts salient objects from infrared images according to pixel threshold segmentation, and extracts background information other than objects from visible images. Then the salience-combined map is used to guide the initial fusion image to get the final image. In our qualitative analysis, we compared our method against 5 traditional methods and deep learning-based methods. In the quantitative assessment, utilizing 29 pairs of randomly selected source images, our algorithm distinctly showcased absolute superiority across various metrics, including EN, SF, AG, and FD. The aforementioned results affirm that our method ensures the generation of fused images with clear targets and rich details. [ABSTRACT FROM AUTHOR]

In recent years, thermal imaging and sensing technologies have seen dramatic increases in usage for a range of applications. However, the material cost and manufacturing complexity of infrared optics remain a major barrier toward their democratization. Here, a solution‐processed plasmonic reflective filter (PRF) is presented as a scalable, disordered, and low‐cost thermal infrared (TIR) optic. The PRF selectively absorbs sunlight and specularly reflects TIR wavelengths, with a performance comparable to state‐of‐the‐art infrared optics made of materials like Germanium. Unlike the latter, however, the PRF is fabricated using low‐cost materials and a “dip‐and‐dry” chemical synthesis technique, which enables orders of magnitude lower manufacturing costs. The PRF's optical functionality and integration into infrared imaging systems are experimentally demonstrated. The chemical synthesis technique also affords exceptional spectral tuneability and material compatibility compared to traditional fabrication methods. The PRF's tuneable and broadband TIR yield can be augmented by inexpensive dielectric or polymeric filters to yield novel capabilities such as wide‐area ambient temperature surveys. Practically, the PRF represents a significant advance toward democratizing the benefits of thermal imaging and sensing. Scientifically, it represents a previously unexplored optical functionality of disordered materials, and a new direction for versatile chemical synthesis in designing optical components. [ABSTRACT FROM AUTHOR]

Unmanned Aerial Vehicle (UAV) infrared detection has problems such as weak and small targets, complex backgrounds, and poor real-time detection performance. It is difficult for general target detection algorithms to achieve the requirements of a high detection rate, low missed detection rate, and high real-time performance. In order to solve these problems, this paper proposes an improved small target detection method based on Picodet. First, to address the problem of poor real-time performance, an improved lightweight LCNet network was introduced as the backbone network for feature extraction. Secondly, in order to solve the problems of high false detection rate and missed detection rate due to weak targets, the Squeeze-and-Excitation module was added and the feature pyramid structure was improved. Experimental results obtained on the HIT-UAV public dataset show that the improved detection model's real-time frame rate increased by 31 fps and the average accuracy (MAP) increased by 7%, which proves the effectiveness of this method for UAV infrared small target detection. [ABSTRACT FROM AUTHOR]

Many rocks, minerals, and soil types reflect short-wave infrared (SWIR) imagery (900–2500 nm) in distinct ways, and geologists have long relied on this property to aid in the mapping of differing surface lithologies. Although surface archaeological features including artifacts, anthrosols, or structural remains also likely reflect SWIR wavelengths of light in unique ways, archaeological applications of SWIR imagery are rare, largely due to the low spatial resolution and high acquisition costs of these data. Fortunately, a new generation of compact, drone-deployable sensors now enables the collection of ultra-high-resolution (<10 cm), hyperspectral (>100 bands) SWIR imagery using a consumer-grade drone, while the analysis of these complex datasets is now facilitated by powerful imagery-processing software packages. This paper presents an experimental effort to develop a methodology that would allow archaeologists to collect SWIR imagery using a drone, locate surface artifacts in the resultant data, and identify different artifact types in the imagery based on their reflectance values across the 900–1700 nm spectrum. Our results illustrate both the potential of this novel approach to exploring the archaeological record, as we successfully locate and characterize many surface artifacts in our experimental study, while also highlighting challenges in successful data collection and analysis, largely related to current limitations in sensor and drone technology. These findings show that as underlying hardware sees continued improvements in the coming years, drone-acquired SWIR imagery can become a powerful tool for the discovery, documentation, and analysis of archaeological landscapes. [ABSTRACT FROM AUTHOR]

Simple Summary: The poultry industry is advancing through a focus on nutrition, management practices, and technology to enhance productivity by improving feed conversion ratios, disease control, lighting management, and exploring antibiotic; alternatives. Infrared (IR) radiation, with wavelengths ranging from 760 to 10,000 nm, is being used to improve the well-being of humans, animals, and poultry. IR applications like heating, spectroscopy, beak trimming, and other therapies offer health benefits such as improved skin health, wound healing, and enhanced immune responses. In poultry production, IR radiation positively impacts growth performance, gut health, blood profiles, and food safety. Despite its benefits, applications of IR in poultry are limited but show promise for wider adoption. This innovative approach has the potential to revolutionize traditional practices in the industry by optimizing productivity and efficiency while improving animal welfare. The poultry industry is dynamically advancing production by focusing on nutrition, management practices, and technology to enhance productivity by improving feed conversion ratios, disease control, lighting management, and exploring antibiotic alternatives. Infrared (IR) radiation is utilized to improve the well-being of humans, animals, and poultry through various operations. IR radiation occurs via electromagnetic waves with wavelengths ranging from 760 to 10,000 nm. The biological applications of IR radiation are gaining significant attention and its utilization is expanding rapidly across multiple sectors. Various IR applications, such as IR heating, IR spectroscopy, IR thermography, IR beak trimming, and IR in computer vision, have proven to be beneficial in enhancing the well-being of humans, animals, and birds within mechanical systems. IR radiation offers a wide array of health benefits, including improved skin health, therapeutic effects, anticancer properties, wound healing capabilities, enhanced digestive and endothelial function, and improved mitochondrial function and gene expression. In the realm of poultry production, IR radiation has demonstrated numerous positive impacts, including enhanced growth performance, gut health, blood profiles, immunological response, food safety measures, economic advantages, the mitigation of hazardous gases, and improved heating systems. Despite the exceptional benefits of IR radiation, its applications in poultry production are still limited. This comprehensive review provides compelling evidence supporting the advantages of IR radiation and advocates for its wider adoption in poultry production practices. [ABSTRACT FROM AUTHOR]

The obsidian dating method converts the quantity of diffused molecular water within a near‐surface hydration layer to elapsed time using an experimentally derived diffusion coefficient predicted from the structural water content of the glass. Infrared spectroscopic transmission measurements on transparent archaeological samples record vibrational responses of water bands in the near‐infrared region, permitting determination of structural water content (OH), and the amount of diffused ambient water (H2O). In this application, the H2O water band at 5200 cm−1 is measured directly. The accuracy of the approach is assessed by an evaluation of the precision of each contributing variable. The new protocol is evaluated using obsidian artifacts from radiocarbon‐dated deposits at Salamanca Cave in Argentina. [ABSTRACT FROM AUTHOR]

A device that can dynamically control the reflection, transmission, and absorption of infrared thermal radiation is essential for the development of a broad range of infrared (IR) technologies. However, realizing efficient thermal emission regulation is challenging due to the inherent complexity or limitation in traditional radiative materials or structures. Here, we design a memristor-type, tunable IR emissivity device composed of an indium tin oxide/tungsten trioxide/gold (ITO/WO3/Au) nanoscale multilayer structure. The device exhibits resonant characteristics in optics and memristive behavior in electronics, as evidenced by the results of both optical and electrical analyses. The emissivity variation of the proposed device is 0.32 in the range of 2.5–25 μm. Moreover, a transparent memristor-type device was fabricated and combined with a V2O5–WO3-based electrochromic device to decouple the IR emissivity and visible color, enabling tunable visible-infrared compatible applications. This investigation will provide a novel nanoscale design approach for dynamic thermal emission control in fundamental science and can significantly benefit a number of applications, including energy-efficient thermoregulation, information encryption, thermal signature masking, and radiative cooling. [ABSTRACT FROM AUTHOR]

Face recognition has been well studied under visible light and infrared (IR) in both intra-spectral and cross-spectral cases. However, how to fuse different light bands for face recognition, i.e., hyperspectral face recognition, is still an open research problem, which has the advantages of richer information retention and all-weather functionality over single-band face recognition. Thus, in this research, we revisit the hyperspectral recognition problem and provide a deep learning-based approach. A new fusion model (named HyperFace) is proposed to address this problem. The proposed model features a pre-fusion scheme, a Siamese encoder with bi-scope residual dense learning, a feedback-style decoder, and a recognition-oriented composite loss function. Experiments demonstrate that our method yields a much higher recognition rate than face recognition using only visible light or IR data. Moreover, our fusion model is shown to be superior to other general-purpose image fusion methods that are either traditional or deep learning-based, including state-of-the-art methods, in terms of both image quality and recognition performance. [ABSTRACT FROM AUTHOR]

Due to a legacy originating in the limited capability of early computers, the spectroscopic resolution used in Fourier transform infrared spectroscopy and other systems has largely been implemented using only powers of two for more than 50 years. In this study, we investigate debunking the spectroscopic lore of, e.g., using only 2, 4, 8, or 16 cm−1 resolution and determine the optimal resolution in terms of both (i) a desired signal-to-noise ratio and (ii) efficient use of acquisition time. The study is facilitated by the availability of solids and liquids reference spectral data recorded at 2.0 cm−1 resolution and is based on an examination in the 4000–400 cm−1 range of 61 liquids and 70 solids spectra, with a total analysis of 4237 peaks, each of which was also examined for being singlet/multiplet in nature. Of the 1765 liquid bands examined, only 27 had widths <5 cm−1. Of the 2472 solid bands examined, only 39 peaks have widths <5 cm−1. For both the liquid and solid bands, a skewed distribution of peak widths was observed: For liquids, the mean peak width was 24.7 cm−1 but the median peak width was 13.7 cm−1, and, similarly, for solids, the mean peak width was 22.2 cm−1 but the median peak width was 11.2 cm−1. While recognizing other studies may differ in scope and limiting the analysis to only room temperature data, we have found that a resolution to resolve 95% of all bands is 5.7 cm−1 for liquids and 5.3 cm−1 for solids; such a resolution would capture the native linewidth (not accounting for instrumental broadening) for 95% of all the solids and liquid bands, respectively. After decades of measuring liquids and solids at 4, 8, or 16 cm−1 resolution, we suggest that, when accounting only for intrinsic linewidths, an optimized resolution of 6.0 cm−1 will capture 91% of all condensed-phase bands, i.e., broadening of only 9% of the narrowest of bands, but yielding a large gain in signal-to-noise with minimal loss of specificity. [ABSTRACT FROM AUTHOR]

Retro-reflective materials are gradually increasing in popularity and use due to their safety properties, and aesthetic advantages. This study details an experimental procedure of the functional performance of silver (Ag), stainless steel (SS), and titanium (Ti) coatings of 150 nm in thickness on retro-reflective fabrics (with plain, twill and diamond weave structures) via magnetron sputtering. The deposited thin films were characterised using CIE L* a* b* values, SEM, contact angle, air permeability, thermal conductivity, anti-static, IR and UV protection. The results reveal that Ag coated fabric can transfer away body heat, hence ensuring a feeling of coolness. The Ag coated fabric samples have an overall good infrared (IR) protective property followed by SS, with Ti having a poor IR protective performance. All of the coated fabrics show excellent ultraviolet protection with 50+ UPF ratings. Furthermore, the coated fabrics have good anti-static properties which prevent the build-up of static charge that can cause discomfort to the wearer, especially in dry weather conditions. The deposition of Ag, SS or Ti nanoparticles on the surface of the fabric increases the hydrophobicity of the material or results in a fabric with low wettability as evident from the measured contact angles. [ABSTRACT FROM AUTHOR]

Infrared analysis reveals the presence of interwoven inclusions, primarily comprised of silicon nitride and silicon carbide, in the casting process of monocrystalline silicon ingots. This study investigates how the longitudinal temperature gradient affects the removal of inclusions during the casting of monocrystalline silicon ingots through simulations and comparative experiments. Two monocrystalline silicon ingots were cast, each using different longitudinal temperature gradients: one employing smaller gradients and the other conventional gradients. CGSim (Version Basic CGSim 23.1) simulation software was utilized to analyze the melt flow and temperature distribution during the growth process of quasi–monocrystalline silicon ingots. The findings indicate that smaller longitudinal temperature gradients lead to a more robust upward flow of molten silicon at the solid–liquid interface, effectively carrying impurities away from this interface and preventing their inclusion formation. Analysis of experimental photoluminescence and IR results reveals that although inclusions may not be observed, impurities persist but are gradually displaced to the top of the silicon melt through a stable growth process. [ABSTRACT FROM AUTHOR]