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A series of Ce4+-doped Pr 2 Zr 2 O 7 ceramics were produced using a solid reaction method to utilize novel ceramic materials as potential candidates for thermally protective coatings. The effects of Ce4+ doping on the phase composition and mechanical, infrared radiative, and thermophysical properties were studied in detail. The results indicated the good phase stability and sintering resistance of the Pr 2 (Zr 1−x Ce x) 2 O 7 ceramics. Moreover, Ce4+-doped Pr 2 Zr 2 O 7 bulk materials exhibited higher infrared emissivity (0.904) at wavelengths of 3–5 μm and 1000 °C for Pr 2 (Zr 0.5 Ce 0.5) 2 O 7) owing to the introduction of impurity energy levels. Pr 2 (Zr 0.7 Ce 0.3) 2 O 7 exhibited an appropriate average coefficient of thermal expansion of 12.4 × 10−6 K−1 and a low thermal conductivity of 1.14 W m−1 K−1 at 1000 °C, owing to the reduction of lattice energy and the presence of more oxygen vacancies and substitution atoms. [ABSTRACT FROM AUTHOR]

High temperature material with low infrared emissivity in 3–5 μm waveband plays a crucial role in the infrared stealth capability of hot-end aircraft components. In this study, 3 mol% Ce doped ZnO ceramic powders were annealed at various temperatures to reduce their infrared emissivity. The effects of the annealing temperature on the lattice structure, microscopic morphology, and elemental valence variation in the ZnO ceramic powders were systematically investigated. Additionally, a conductivity–dielectric–lattice vibration synergy theory was proposed to provide insights about the changes in the infrared emissivity of the ZnO ceramic powders. The infrared emissivity of the sample powder gradually decreased to its lowest value (0.092 at 500 °C) as the annealing temperature increased to 1100 °C, exhibiting a U-shaped curve from room temperature to 800 °C. Furthermore, the obtained powder was used as a filler to prepare a low infrared emissivity coating, which exhibited an infrared emissivity of 0.213 in 3–5 μm waveband at 500 °C. An infrared thermographic analysis of the coating indicated that it significantly suppressed infrared radiation at 500 °C, demonstrating an excellent high temperature infrared stealth performance. [ABSTRACT FROM AUTHOR]

High infrared radiation materials have crucial applications in energy saving, heat conversion, and heat dissipation. SrZrO 3 (SZO) is a potential material for high infrared radiation, however, its infrared emissivity still needs to be improved. To address this, in this study, Sr(Zr 0.9375 Cu 0.0625)O 3-δ (SZCO) perovskite ceramic with high infrared emissivity was prepared, and the impact of Cu ion doping on the electronic structure, infrared radiation characteristics, and thermal conductivity of SrZrO 3 were explored. The findings reveal that SZO doped with Cu ions markedly decreases its band gap width from 5.658 eV to 1.467 eV. The infrared emissivity of the SZCO ceramic, sintered at 1200 °C, increases by 28 % in the 3–5 μm band compared to SZO at room temperature. This emissivity positively correlates with temperature, reaching up to 0.95 at 600 °C. The emissivities of SZCO are greater than that of SZO in the 8–14 μm and 1–22 μm band ranges over the test temperature range from room temperature to 600 °C, and both increase with increasing temperature, reaching 0.978 and 0.946 at 600 °C, respectively. Furthermore, the SZCO ceramic demonstrates thermal conductivities ranging from 1.90 to 3.2 W m−1 K−1 below 1400 °C. These results highlight the potential of Sr(Zr 0.9375 Cu 0.0625)O 3-δ ceramic as a high infrared radiation material. [ABSTRACT FROM AUTHOR]

Colorimetric temperature measurement is an essential technique in radiometric thermometry. Traditional colorimetric methods determine temperature by comparing the ratio of radiative energies within two narrow bands at specific wavelengths, effectively mitigating the effects of the emissivity of the measured object and ambient conditions. However, these methods typically approximate integration using area calculations when calculating radiative energy. This article eliminates this approximation and calculates the radiative energy with accurate integration. Based on the principle of monotonicity, this article demonstrates for the first time that when two narrow-band infrared radiations are selected, as long as their wavelength ranges do not overlap, the ratio of radiative energies within these bands maintains a monotonic relationship with the measured temperature. This allows the temperature to be inferred from the energy ratio. Furthermore, this conclusion is extended to arbitrary widths of bands as long as their wavelength ranges do not overlap. Building on this foundation, a thermopile-based colorimetric temperature measurement method for arbitrary bandwidth is proposed. Simulation experiments validate this method, showing that the energy ratio maintains a monotonic relationship with the measured temperature as long as the infrared radiation wavelength ranges absorbed by the thermopile do not overlap. The simulation results are consistent with the mathematical proof. [ABSTRACT FROM AUTHOR]

The instability and failure processes of coal-rock combinations are accompanied by the release of acoustic emission (AE) and infrared radiation (IR) signals. To investigate the characteristics of AE and IR signals during the failure process in coal-rock combinations with different ratios, and to analyze the effectiveness and applicability of the monitoring methods for these two signals in various specimen ratios. In this paper, the uniaxial compression tests were conducted on seven coal-rock combinations with different ratios by using the rock mechanics loading system and the cooperative monitoring platform of infrared and acoustic emission. The results show that (1) the AE counts for failure precursors in coal-rock combinations are positively correlated with the coal-rock ratio, whereas the AE peak counts are negatively correlated. Moreover, as the coal-rock ratio decreases, the slope of the cumulative AE count curve during the peak failure stage approaches 1. (2) During the elastic and yield stages, the maximum infrared radiation temperature (MIRT) curve fluctuates, and just before peak failure, the curve displays a distinctive "V" shape. This "V" shape becomes more pronounced as the coal-rock ratio decreases. (3) In the monitoring of damage precursors of coal-rock combinations, when the ratio of coal to rock is 1:3 or less, IR monitoring is better than AE monitoring. Conversely, when the ratio of coal to rock is greater than 1:3, AE monitoring is more suitable. Consequently, the combined monitoring of AE and IR signals can increase the reliability and precision of early warning signals for coal-rock assemblage damage precursors. [ABSTRACT FROM AUTHOR]

Filtered-sunlight phototherapy (FSPT) that blocks ultraviolet light and reduces infrared radiation is safe and non-inferior to intensive electric phototherapy (IEPT) for treating mild-to-severe neonatal hyperbilirubinemia. In this randomized non-inferiority trial, the safety, efficacy, exchange transfusion (ET), and mortality rates of FSPT versus IEPT among Nigerian neonates with severe-to-hazardous hyperbilirubinemia were investigated. Safety was defined as the absence of hyperthermia, hypothermia, dehydration, or sunburn; efficacy by the proportion of assessable treatment days during which total serum or plasma bilirubin (TSB) increased by < 0.2 mg/dL/hr for newborns aged ≤ 72 h-old or decreased for newborns > 72 h-old. A treatment day was deemed assessable if a neonate received phototherapy for ≥ 4 h, and non-inferiority was inferred for differences within a 10% margin. We enrolled 192 newborns (admission TSB ≤ 62 mg/dL), assigned to FSPT (n = 98) or IEPT (n = 94). FSPT was effective on 94.2% of the assessable treatment days compared with 97.1% for IEPT. The mean difference in efficacy between FSPT and IEPT was -2.9%, 95% CI: -7.6, 1.9). 2.6% of newborns who received FSPT developed controlled hyperthermia, and no baby met the criteria for withdrawal for safety reasons. Overall, 50.6% (39/77) of newborns who received FSPT and 53.7% (51/95) of newborns who received IEPT had ET (p = 0.89) and 7 in each group (9.1% vs 7.4%; p = 0.86) died. In conclusion, FSPT is safe and non-inferior to IEPT for treating neonates with severe-to-hazardous hyperbilirubinemia, it is not associated with significantly higher rates of ET and mortality and should be considered where practicable when IEPT cannot be assured. Clinical Trials.gov Number: NCT02612727 (24/11/2015). [ABSTRACT FROM AUTHOR]

The environmental noise have a negative influence on the quality of infrared thermal imaging of the rocket exhaust plume. In this study, the noise data of the unsteady rocket exhaust plume flow field was simulated using Gaussian white noise, and the infrared thermal image of the plume was numerically calculated using the narrow band method (SNB) and the line of sight (LOS) method. The denoising of infrared thermal imaging was achieved through the spectral proper orthogonal decomposition (SPOD) inversion method. Results indicate that Gaussian white noise leads to larger infrared thermal image residuals in the intrinsic core of the plume compared to the mixed regions. The infrared thermal image in the 2.7 μm band is greatly affected by the noise with an average error of 21.1%, and the average error in the 4.3 μm band is 17.6%. After SPOD denoising, the error of the plume infrared thermal image is reduced by more than 50%. [ABSTRACT FROM AUTHOR]

Far infrared radiation (FIR) within the wavelength range of 4–14 μm can offer human health benefits, such as improving blood flow. Therefore, additives that emit far infrared radiation have the potential to be incorporated into polymer/fabric matrices to develop textiles that could promote health. In this study, biochar derived from candlenuts and pyrolyzed with activated carbon (AC) was incorporated into polypropylene (PP) films and investigated for its potential as a health-promoting textile additive. The properties of biochar were compared with other far infrared (FIR) emitting additives such as hematite, Indian red ochre, and graphene. The addition of biochar increased FIR emissivity to 0.90, which is 9% higher than that of pristine PP. Additionally, biochar enhanced UV and near-infrared (NIR) blocking capabilities, achieving an ultra-protection factor (UPF) of 91.41 and NIR shielding of 95.85%. Incorporating 2 wt% biochar resulted in a 3.3-fold higher temperature increase compared to pristine PP after 30 s of exposure to an FIR source, demonstrating improved heat retention. Furthermore, the ability to achieve the lowest thermal effusivity among other additives supports the potential use of biochar-incorporated fabric as a warming material in cold climates. The tensile properties of PP films with biochar were superior to those with other additives, potentially contributing to a longer product lifespan. Additionally, samples with red ochre exhibited the highest FIR emissivity, while samples with hematite showed the highest capacity for UV shielding. [ABSTRACT FROM AUTHOR]

The fusion of infrared and visible images together can fully leverage the respective advantages of each, providing a more comprehensive and richer set of information. This is applicable in various fields such as military surveillance, night navigation, environmental monitoring, etc. In this paper, a novel infrared and visible image fusion method based on sparse representation and guided filtering in Laplacian pyramid (LP) domain is introduced. The source images are decomposed into low- and high-frequency bands by the LP, respectively. Sparse representation has achieved significant effectiveness in image fusion, and it is used to process the low-frequency band; the guided filtering has excellent edge-preserving effects and can effectively maintain the spatial continuity of the high-frequency band. Therefore, guided filtering combined with the weighted sum of eight-neighborhood-based modified Laplacian (WSEML) is used to process high-frequency bands. Finally, the inverse LP transform is used to reconstruct the fused image. We conducted simulation experiments on the publicly available TNO dataset to validate the superiority of our proposed algorithm in fusing infrared and visible images. Our algorithm preserves both the thermal radiation characteristics of the infrared image and the detailed features of the visible image. [ABSTRACT FROM AUTHOR]

Recent work has indicated that atmospheric radiative heating reduces the kinetic energy of large‐scale eddies in the midlatitudes. However, a physical mechanism that connects radiation to the midlatitude eddy kinetic energy is still uncertain. Using a high‐resolution general circulation model we perform an experiment in which the radiative cooling profile at each model time step is overwritten with the climatological mean, computed from a control simulation. This approach separates the mean and transient effects of radiative heating on the extratropical circulation. We find that, when radiative heating is fixed, the globally‐averaged eddy kinetic energy is enhanced by ∼6%. We show that thermal radiation dampens temperature anomalies near the surface and tropopause in low‐pressure systems, destroying eddy available potential energy and eddy kinetic energy. We identify this as a possible mechanism by which atmospheric radiative heating weakens midlatitude cyclones. Plain Language Summary: The atmosphere can be differentially heated through the absorption of visible and infrared radiation by water vapor and clouds. This process of radiative heating is thought to promote the formation of tropical cyclones, but its impact on midlatitude cyclones—storms characterized by the passage of warm and cold fronts—is less clear. Here we show that, unlike tropical cyclones, radiative heating weakens midlatitude storms. We argue that radiative cooling in the warm sector, and radiative heating in the cold sector of midlatitude cyclones, reduces the temperature gradient which is critical for the development of these weather systems. This study underscores an essential difference between tropical and midlatitude storms: in the tropics, temperature gradients are small, but at higher latitudes, temperature gradients are the drivers of storm formation. Key Points: When radiative interactions are suppressed, the global‐mean eddy kinetic energy increases by ∼6%Radiative cooling coincident with positive temperature anomalies destroys eddy available potential energy and eddy kinetic energyThe energetic perspective provides a useful way to understand the effect of radiative heating on the general circulation [ABSTRACT FROM AUTHOR]

In this work, the features of the structure-conductivity relationship in polar (α) and ion-conducting (β and γ) phases of Na3Fe2(PO4)3 polycrystals obtained by the melt-quenching method have been investigated. Na3Fe2(PO4)3 polycrystals are synthesized by isothermal firing of glassy precursors (after grinding and pressing). The glassy precursors were prepared by melting a pre-calcined (350 C) mixture of initial reagents under the influence of thermal and infrared radiation energy and rapid cooling of the melt (or quenching). It was found that the deformations of the structure of polycrystals α-Na3Fe2(PO4)3 during synthesis by melt-quenching lead to an increase in the conductivity in polar (α) and ion-conducting (β and γ) phases because they contribute to the reduction of structural distortions of the samples. Polycrystals Na3Fe2(PO4)3 obtained by the melt-hardening method have high-quality crystallites, high density, and conductivity, and their synthesis is faster than samples obtained by other methods. The established advantages of synthesized polycrystals of α-Na3Fe2(PO4)3 are probably connected with deformations of structure and chemical activity of glassy precursors caused by nonequilibrium thermodynamic conditions of synthesis. For the first time, it was possible to detect domain structures in polycrystals of α-Na3Fe2(PO4)3 obtained by the melt-quenching method, which confirms the polarity of the α-phase, the appearance of which is associated with the ordered displacement of the cationic sublattice relative to the anionic sublattice under the influence of monoclinic distortion of the crystal framework. [ABSTRACT FROM AUTHOR]

The Co-doped α-MoO 3 with thermochromism and variable infrared emissivity were prepared. The defects in the crystal structures and the regulatory mechanism of local defects on band gap width and conductivity were further investigated. The Co-doped α-MoO 3 samples from different heating atmosphere were designed to study the influences of oxygen vacancy on thermochromism and infrared emissivity. Concentration of oxygen vacancy determines optical absorption/reflectivity and conductivity. Results show that the Co-doped α-MoO 3 sample prepared by thermal treatment at 500 °C in argon atmosphere owns appropriate oxygen vacancy, reflectivity and conductivity, rich colorful change and strong infrared radiation regulation. Color can reversibly change from purple to yellow-green, and the effective infrared emissivity is regulated to 0.242 at 3–5 μm. It indicates a new strategy to enhance high temperature thermochromism and variable infrared emissivity by ion doping. • The thermochromic and infrared emissivity of Co-doped α-MoO 3 were changed by the atmosphere and temperature control structure and the band gap. • The changed oxygen vacancy in the interlayer octahedron is the main reason for the varied band gap and conductivity at different temperature. • Co-doped α-MoO 3 thermal treated in argon atmosphere has reversible thermochromic infrared emissivity with Δ ε of 0.242 and color ranging from purple to yellow-green. [ABSTRACT FROM AUTHOR]

During the process of infrared remote sensing monitoring, obtaining real-time measurements of sky background radiation is extremely inconvenient. The current methods incur a certain amount of lag. In this study, within the existing theoretical framework, a fast transmittance calculation method using interpolation was adopted, and a simplified transmission model was established. This led to the development of a new and simplified method for rapid temperature and humidity retrieval. Compared to the line-by-line integration method, the interpolation method significantly improves the speed of transmittance calculation by several tens of times, while maintaining a high level of accuracy. The relative deviation between the results obtained using the interpolation method and those obtained through line-by-line integration is less than 1 ‱. With the proposed method, temperature and humidity profile information can be retrieved from measured spectra within 5 min and corresponding background spectra can be obtained. The differences between the calculated background radiation and the measured spectra using the new method are smaller, making it more suitable for calculating sky background radiation. Additionally, the rapid retrieval results of the temperature profiles in the lower atmosphere have a certain level of accuracy (the mean deviation is less than 2 K). [ABSTRACT FROM AUTHOR]

Millions of people all over the globe are highly affected by arsenic toxicity. The aim of current study was to synthesis of porous geopolymer for effective arsenic As(III) and As (V) sequestration from aqueous solution. In addition to that morphological and chemical analysis of adsorbent was conducted by scanning electron microscopy (SEM), energy dispersion x-ray spectroscopy (EDX) and fourier transform infrared radiations (FTIR) and BET. FTIR results reveled the formation of Si-O-Si and Si-O-Al bonds which confirmed the construction of geopolymer. SEM images represent that adsorbent has a regular, spherical and interconnected porous structure with greater specific surface area and porosity. The best removal efficiency of As(III) was 62% at optimized operating conditions of pH 5-6, adsorbent dose 1 gm and initial concentration of pollutant 50 ppb, however As(V) removal efficiency was 94% at optimized operating conditions of pH 7-9, adsorbent dose 1 gm and initial concentration of pollutant 50 ppb. The experimental results was validated by renowned Freundlich adsorption isotherm model and peuso second order kinetic model. The correlation coefficient R2 value obtained was 0.968 and 0.949 for As(III) and As(V) Freundlich model respectively. While R2 was 0.98 and 0.99 for pseudo second order kinetic model. It was determined from R2 that experimental results fitted well to Freundlich adsoprtion isotherm model and pseudo second order kinetic model. The results shows that adsorption capacity for As(III) and As(v) is greater than adsorption capacity obtained by other researchers using various adsorbents. [ABSTRACT FROM AUTHOR]

Different coal failure impact types exhibit different damage statuses and failure modes, resulting in distinct signal characteristics of infrared radiation (IR) and acoustic emission (AE). This paper combines IR and AE monitoring methods to innovatively establish coal damage and failure precursor warning models and obtains the IR and AE precursor characteristics for different coal failure impact types. This research shows that there is a good correspondence between IR and AE timing and spatial distribution of different coal impact types. As the impact tendency increases, the intensity of IR and AE signals increases with coal failure, and the AE positioning points and IR high-temperature areas tend to concentrate. The coal body gradually changes from tensile failure to shear failure. The shear cracks in the failure stage of coal with no, weak, and strong impact are 39.9%, 50.9%, and 53.7%, respectively. The IR and AE instability precursor point of coal with no, weak, and strong impact occurred at 55.2%, 66.3%, and 93.4% of coal failure, respectively. After the IR and AE combined instability precursor point, the dissipated energy and combined damage variable increase rapidly, and the coal body will undergo instability and failure. The research results provide a theoretical basis for comprehensive monitoring of coal body failure and rock burst. [ABSTRACT FROM AUTHOR]

Background: FIR therapy is used in various medical settings to treat diseases associated with inflammation and edema. Unlike conventional FIR lamp therapy, this study investigated how body fluids change depending on the intensity and duration of FIR irradiation to the whole body. Method: Subjects in group A (n = 27) were exposed to FIR emitted from a loess bio-ball mat set at 40 °C for 30 min, and subjects in group B (n = 27) were exposed to FIR emitted from a loess bio-ball mat set at 30 °C for 7 h during sleep. Changes in bioimpedance parameters and fluid-related values were measured using a body fluid analyzer before and after exposure to FIR. Results: Changes in bioimpedance parameters associated with inflammatory fluids were quantitatively confirmed. In group A, there was a minimal change in fluid-related measurements. However, significant changes in bioimpedance parameters associated with inflammatory fluids were observed in group B exposure to FIR for 7 h during sleep. Conclusions: FIR emitted from loess bio-balls activates biological tissues and lymphatic circulation, gradually reducing the levels of inflammatory fluids over time. [ABSTRACT FROM AUTHOR]

Composites of polyvinyl alcohol and polyvinyl pyrrolidone (PVA/PVP) reinforced with different silicon dioxide (SiO2) loadings (0, 2, 4, and 6) wt.% were obtained via the solution casting method. The electrical and optical properties have been investigated. Fourier-transform infrared ray (FTIR) analysis revealed that the incorporation of SiO2 NPs resulted in an interaction with the polymer matrix. Physical interactions between the (PVA/PVP) polymer matrix and SiO2 NPs have been shown by FTIR analysis. The increase in SiO2 nanoparticle ratio in the PVA/PVP/SiO2 nanocomposite results in a corresponding increase in absorbance and decrease in transmittance. The PVA/PVP/SiO2 nanocomposite exhibited a reduction in energy gap, decreasing from 4.2 eV observed in pure PVA/PVP to 2.6 eV for allowed indirect transition and 4 eV to 2.6 eV for forbidden indirect transition, upon the incorporation of SiO2 nanoparticles at a concentration of 6 wt.%. This result is deemed a key for various optical fields and optoelectronics nanodevices. The weight percentages of SiO2 nanoparticles exhibit a positive correlation with their absorbing coefficient, extinction coefficient, index of refractive, real and imaginary components of dielectric constants, and optical conductivity. The investigation of the nanocomposites has revealed that an increase in the concentration of SiO2 nanoparticles leads to an elevation in both the dielectric constant and dielectric loss, while an increase in the frequency of the applied electric field results in a decrease in these properties. The increase in frequency and weight content of SiO2 NPs results in a corresponding increase in AC electrical conductivity. The results confirm that PVA/PVP/SiO2 films nanocomposites have excellent optical and electrical properties, which could encourage the nanocomposites' application in different electric and optoelectric uses. [ABSTRACT FROM AUTHOR]

This study examined the effects of hot air drying (HAD), infrared radiation drying (IRD), microwave vacuum drying (MVD), freeze drying (FD), and freeze drying combined with microwave vacuum drying (FD-MVD) on the drying kinetics, color, rehydration ratio, titratable acidity, and vitamin C content of small white apricots (Prunus armeniaca L.). Results showed drying times of 12.5 h (IRD), 14.1 h (FD), 16 h (HAD), 0.53 h (MVD), and 6.15 h (FD-MVD). FD-MVD significantly outperformed MVD, HAD, and IRD in color, vitamin C, titratable acidity, and rehydration, though was slightly inferior to FD. Microstructural analysis revealed that FD-MVD preserved the most uniform pore structure, better maintaining apricots' original appearance. In contrast, IRD and HAD caused severe surface shriveling, compromising quality. In conclusion, FD-MVD emerges as a promising drying method to enhance apricot quality and market competitiveness in food processing. [ABSTRACT FROM AUTHOR]

Dynamic manipulation of an object's infrared radiation characteristics is a burgeoning technology with significant implications for energy and information fields. However, exploring efficient stimulus–spectral response mechanism and realizing simple device structures remains a formidable challenge. Here, a novel dynamic infrared emissivity regulation mechanism is proposed by controlling the localized surface plasmon resonance absorption of aluminum‐doped zinc oxide (AZO) nanocrystals through ultraviolet photocharging/oxidative discharging. A straightforward device architecture that integrates an AZO nanocrystal film with an infrared reflective layer and a substrate, functioning as a photo‐induced dynamic infrared emissivity modulator, which can be triggered by weak ultraviolet light in sunlight, is engineered. The modulator exhibits emissivity regulation amount of 0.72 and 0.61 in the 3–5 and 8–13 µm ranges, respectively. Furthermore, the modulator demonstrates efficient light triggering characteristic, broad spectral range, angular‐independent emissivity, and long cyclic lifespan. The modulator allows for self‐adaptive daytime radiative cooling and nighttime heating depending on the ultraviolet light in sunlight and O2 in air, thereby achieving smart thermal management for buildings with zero‐energy expenditure. Moreover, the potential applications of this modulator can extend to rewritable infrared displays and deceptive infrared camouflage. [ABSTRACT FROM AUTHOR]

Surface downward longwave radiation (SDLR) is crucial for maintaining the global radiative budget balance. Due to their ease of practicality, SDLR parameterization models are widely used, making their objective evaluation essential. In this study, against comprehensive ground measurements collected from more than 300 globally distributed sites, four SDLR parameterization models, including three popular existing ones and a newly proposed model, were evaluated under clear- and cloudy-sky conditions at hourly (daytime and nighttime) and daily scales, respectively. The validation results indicated that the new model, namely the Peng model, originally proposed for SDLR estimation at the sea surface and applied for the first time to the land surface, outperformed all three existing models in nearly all cases, especially under cloudy-sky conditions. Moreover, the Peng model demonstrated robustness across various land cover types, elevation zones, and seasons. All four SDLR models outperformed the Global Land Surface Satellite product from Advanced Very High-Resolution Radiometer Data (GLASS-AVHRR), ERA5, and CERES_SYN1de-g_Ed4A products. The Peng model achieved the highest accuracy, with validated RMSE values of 13.552 and 14.055 W/m2 and biases of −0.25 and −0.025 W/m2 under clear- and cloudy-sky conditions at daily scale, respectively. Its superior performance can be attributed to the inclusion of two cloud parameters, total column cloud liquid water and ice water, besides the cloud fraction. However, the optimal combination of these three parameters may vary depending on specific cases. In addition, all SDLR models require improvements for wetlands, bare soil, ice-covered surfaces, and high-elevation regions. Overall, the Peng model demonstrates significant potential for widespread use in SDLR estimation for both land and sea surfaces. [ABSTRACT FROM AUTHOR]

The atmosphere is a complex nonlinear system, with the information of its temperature, water vapor, pressure, and cloud being crucial aspects of remote-sensing data analysis. There exist intricate interactions among these internal components, such as convection, radiation, and humidity exchange. Atmospheric phenomena span multiple spatial and temporal scales, from small-scale thunderstorms to large-scale events like El Niño. The dynamic interactions across different scales, along with external disturbances to the atmospheric system, such as variations in solar radiation and Earth surface conditions, contribute to the chaotic nature of the atmosphere, making long-term predictions challenging. Grasping the intrinsic chaotic dynamics is essential for advancing atmospheric analysis, which holds profound implications for enhancing meteorological forecasts, mitigating disaster risks, and safeguarding ecological systems. To validate the chaotic nature of the atmosphere, this paper reviewed the definitions and main features of chaotic systems, elucidated the method of phase space reconstruction centered on Takens' theorem, and categorized the qualitative and quantitative methods for determining the chaotic nature of time series data. Among quantitative methods, the Wolf method is used to calculate the Largest Lyapunov Exponents, while the G–P method is used to calculate the correlation dimensions. A new method named Improved Saturated Correlation Dimension method was proposed to address the subjectivity and noise sensitivity inherent in the traditional G–P method. Subsequently, the Largest Lyapunov Exponents and saturated correlation dimensions were utilized to conduct a quantitative analysis of FY-4A and Himawari-8 remote-sensing infrared observation data, and ERA5 reanalysis data. For both short-term remote-sensing data and long-term reanalysis data, the results showed that more than 99.91% of the regional points have corresponding sequences with positive Largest Lyapunov exponents and all the regional points have correlation dimensions that tended to saturate at values greater than 1 with increasing embedding dimensions, thereby proving that the atmospheric system exhibits chaotic properties on both short and long temporal scales, with extreme sensitivity to initial conditions. This conclusion provided a theoretical foundation for the short-term prediction of atmospheric infrared radiation field variables and the detection of weak, time-sensitive signals in complex atmospheric environments. [ABSTRACT FROM AUTHOR]

Background: Early diagnosis of primary Sjögren's syndrome (pSS) remains difficult due to its insidious onset. Objectives: To identify whether meibomian gland dropout (MGD) is a sensitive and noninvasive predictor of pSS by studying its association with histopathology in labial salivary gland biopsy in patients with clinically suspected pSS. Design: Prospective, randomized, multicenter, comparative effectiveness study. Methods: The study was conducted from July 2022 to July 2023. In all, 56 eligible participants with clinically suspected pSS were recruited from three combined ophthalmology medicine/rheumatology SS clinics. All participants with suspected pSS were evaluated and diagnosed by ophthalmology and rheumatology consultants and underwent infrared imaging of the meibomian glands using Keratograph 5M and histopathological evaluation of labial salivary gland biopsies. The length, width, and tortuosity of the meibomian glands were measured; the dropout rate in the nasal, temporal, and total eyelids was analyzed; and the dropout score was calculated using meibography grading scales. Results: Among the 56 participants, 34 were identified with pSS, and 22 were diagnosed with non-SS dry eye (NSSDE) and served as the control group. We recorded significant differences in the temporal and total MGD rates of the upper eyelids between the pSS and NSSDE groups (all p < 0.01). Improved prediction accuracy was achieved with the temporal and total MGD rates in the upper eyelids, with area under the curve values of 0.94 and 0.91, and optimal cutoff points of 0.78 and 0.75, respectively. Conclusion: MGD in the upper eyelids, especially in the temporal portion, is strongly associated with the histopathological outcome of labial salivary gland biopsy in pSS and is proposed as a highly predictive and noninvasive biomarker for the early diagnosis of pSS. Trial registration: ClinicalTrials.gov identifier: ChiCTR2000038911. [ABSTRACT FROM AUTHOR]

The significance of soil in the agricultural industry is profound, with healthy soil representing an important role in ensuring food security. In addition, soil is the largest terrestrial carbon sink on earth. The soil carbon pool is composed of both inorganic and organic forms. The equilibrium of the soil carbon pool directly impacts the carbon cycle via all of the other processes on the planet. With the development of agricultural systems from traditional to conventional ones, and with the current era of precision agriculture, which involves making decisions based on information, the importance of understanding soil is becoming increasingly clear. The control of microenvironment conditions and soil fertility represents a key factor in achieving higher productivity in these systems. Furthermore, agriculture represents a significant contributor to carbon emissions, a topic that has become timely given the necessity for carbon neutrality. In addition to these concerns, updating soil-related data, including information on macro and micronutrient conditions, is important. Carbon represents one of the major nutrients for crops and plays a key role in the retention and release of other nutrients and the management of soil physical properties. Despite the importance of carbon, existing analytical methods are complex and expensive. This discourages frequent analyses, which results in a lack of soil carbon-related data for agricultural fields. From this perspective, in situ soil organic carbon (SOC) analysis can provide timely management information for calibrating fertilizer applications based on the soil–carbon relationship to increase soil productivity. In addition, the available data need frequent updates due to rapid changes in ecosystem services and the use of extensive fertilizers and pesticides. Despite the importance of this topic, few studies have investigated the potential of image analysis based on image processing and spectral data recording. The use of spectroscopy and visual color matching to develop SOC predictions has been considered, and the use of spectroscopic instruments has led to increased precision. Our extensive literature review shows that color models, especially Munsell color charts, are better for qualitative purposes and that Cartesian-type color models are appropriate for quantification. Even for the color model, spectroscopy data could be used, and these data have the potential to improve the precision of measurements. On the other hand, mid-infrared radiation (MIR) and near-infrared radiation (NIR) diffuse reflection has been reported to have a greater ability to predict SOC. Finally, this article reports the availability of inexpensive portable instruments that can enable the development of in situ SOC analysis from reflection and emission information with the integration of images and spectroscopy. This integration refers to machine learning algorithms with a reflection-oriented spectrophotometer and emission-based thermal images which have the potential to predict SOC without the need for expensive instruments and are easy to use in farm applications. [ABSTRACT FROM AUTHOR]

Thermal radiation coating with low thermal conductivity and high infrared emissivity are desirable. In this work, a novel rare‐earth aluminate (PrAlO3+δ with rhombohedral structure) was synthesized via solid‐state reaction method, and the corresponding coating was fabricated using atmospheric plasma spraying (APS). The study encompassed an investigation into the phase structure, high‐temperature phase stability, thermo‐mechanical characteristics, and infrared properties. The results illustrate that as‐deposited coating contained amorphous phase, but recrystallized coating presented phase stability up to 1600°C. Furthermore, the recrystallized coating exhibited low thermal conductivity of 1.35 W/m K at 900°C as well as an average coefficient of thermal expansion of 10.36 × 10−6/K. Also, the coating exhibited high infrared emissivity related to high valance state (Pr4+) and oxygen vacancies. And the average infrared emissivity within 2–14 µm was 0.822 at 1300°C and presented slight decrease with the increase of temperature (the average infrared emissivity of 0.795 at 1800°C). [ABSTRACT FROM AUTHOR]

In this paper, cordierite ceramics with high far-infrared emission properties are synthesized by a high-temperature solid-phase method using molybdenum tailings and vanadium-titanium magnetite tailings. The microstructure, physical properties and far-infrared emission mechanism of ceramics are investigated. The results show that the ceramics synthesized with 10 wt% molybdenum tailings and 30 wt% vanadium-titanium magnetite tailings have a flexural strength of 67 MPa, a bulk density of 2.531 g/cm3 and a maximum far-infrared emissivity of 0.958 when the sintering temperature is 1200 °C. The crystal phase of the ceramic are 21.4 % cordierite and 58.7 % magnesia-alumina spinel. In the sintering process, the Fe3+ in vanadium-titanium magnetite tailings doped into the cordierite to substitute the Mg2+, which has the similar ionic radius with Fe3+, to form a substitutional solute. Ionic substitution causes the lattice parameters of cordierite larger, reducing the symmetry of the lattice vibrations and leading to lattice distortion. In addition, the composition of a large amount of magnesia-aluminum spinel is attributed to the far-infrared emission properties of ceramics. [ABSTRACT FROM AUTHOR]

We use non-destructive Digital Holographic Speckle Pattern Interferometry (DHSPI), post-processing image analysis and one-dimensional exponential analysis to visualize, map and describe the structural condition of a plaster-based material. The body is heated by infrared radiation for two different time windows and the cooling process that follows is monitored in time by the so-called interferograms that are developed and are the result of the superposition of the holographic recordings of the sample prior to the thermal load and at variable time intervals during the cooling process. The fringe patterns in the interferometric images reveal features and characteristics of the interior of the material, with the experimental method and the post-process analysis adopted in this work offering accuracy, sensitivity and full-field diagnosis, in a completely non-destructive manner, without the need of sampling. [ABSTRACT FROM AUTHOR]

This article presents the results of research work devoted to improving the characteristics of paint and varnish coatings based on aqueous dispersions of polyacrylates; it is proposed to modify them by introducing mineral raw materials as fillers and hydrated lime, with subsequent processing in a vortex layer apparatus. The introduction of activated diatomite does not cause the deterioration of covering power, adhesion or an increase in the porosity of the paint material. The modification of coatings contributes to an increase in their operational properties, which can be associated with a reduction in the free volume in the composite and the formation of polymer boundary layers with modified physical and chemical properties. The aim of this study is to obtain a water-dispersion paint and varnish composition containing modified diatomite on a polyacrylate basis and, subsequently, study its main physical and mechanical parameters. The work has been carried out by the following method: determination of porosity, adhesion, elasticity and covering power of the control composition; determination of porosity, adhesion, elasticity and covering power of the obtained composites using modified filler; investigation of the influence of radiation on the infrared spectrum of the paint coating surface using a FLIRB620 thermal imager. As a result of this research work, it was noticed that the modification of water dispersions with silica-activated diatomite helps to eliminate the main disadvantages of materials and coatings based on acrylate binders—low water resistance and low physical and mechanical characteristics. The introduction of modified diatomite into water-emulsion paint on an acrylate base does not lead to the deterioration of the main performance characteristics of paint coatings—porosity, adhesion, elasticity and covering. [ABSTRACT FROM AUTHOR]

Abstract The instability and failure processes of coal-rock combinations are accompanied by the release of acoustic emission (AE) and infrared radiation (IR) signals. To investigate the characteristics of AE and IR signals during the failure process in coal-rock combinations with different ratios, and to analyze the effectiveness and applicability of the monitoring methods for these two signals in various specimen ratios. In this paper, the uniaxial compression tests were conducted on seven coal-rock combinations with different ratios by using the rock mechanics loading system and the cooperative monitoring platform of infrared and acoustic emission. The results show that (1) the AE counts for failure precursors in coal-rock combinations are positively correlated with the coal-rock ratio, whereas the AE peak counts are negatively correlated. Moreover, as the coal-rock ratio decreases, the slope of the cumulative AE count curve during the peak failure stage approaches 1. (2) During the elastic and yield stages, the maximum infrared radiation temperature (MIRT) curve fluctuates, and just before peak failure, the curve displays a distinctive “V” shape. This “V” shape becomes more pronounced as the coal-rock ratio decreases. (3) In the monitoring of damage precursors of coal-rock combinations, when the ratio of coal to rock is 1:3 or less, IR monitoring is better than AE monitoring. Conversely, when the ratio of coal to rock is greater than 1:3, AE monitoring is more suitable. Consequently, the combined monitoring of AE and IR signals can increase the reliability and precision of early warning signals for coal-rock assemblage damage precursors.

The aim of the study was to present various types of radiation that can increase the effectiveness of combined photodynamic therapy (PDT) for malignant and premalignant lesions. Material and Methods. The Web of Science, Scopus, MedLine, Library, and RSCI databases were used for finding publications on this topic, mainly over the last 10 years. Of 230 sources, 64 were included in the review. Results. Photodynamic therapy is a new cancer treatment technology that has become increasingly popular in recent years. It is often an alternative method of treating cancer when there is a high risk of side effects and complications during traditional treatments such as surgery, radiation therapy and chemotherapy. PDT requires a photosensitizer, light energy, and oxygen to create reactive oxygen species that destroy cancer cells. This review examines the basic principles and mechanisms of PDT used alone and in combination with other traditional therapies. Despite the fact that PDT is an effective and non-invasive cancer treatment, it has some limitations, such as low light penetration depth, ineffective photosensitizers and tumor hypoxia. Our study examines new strategies that use other energy sources, such as infrared- and x-rays, ultrasound, as well as electric and magnetic fields, to enhance the PDT effect and overcome its limitations. Great hopes are also associated with the use of a combination of PDT and neutron capture therapy (NСT). Currently, chlorin derivatives associated with boron carriers have been developed. They can be used for both fluorescence diagnostics and PDT, as well as for NСT. The synthesized compounds have a high selectivity of accumulation in the tumor. To date, encouraging preclinical results of high efficiency of combined use of NСT and PDT have already been obtained. Conclusion. Combination with various energy sources is a key factor for further development of PDT. Future research aimed at overcoming the limitations of PDT will contribute to unlocking the full potential of this technology in clinical practice.

The purpose of this article is to identify the possibility of infrared computer thermography for diagnosing the development of plastic deformations of steel products. Methods of conducted experimental studies were published. The results of experiments are presented and analyzed. The possibility of application of infrared computer thermography for research of regularities of origin, propagation and localization of plastic deformation in steel elements during their deformation at room temperatures and after preliminary cooling is substantiated. It is shown that for smooth specimens with distance from the machine grip, the temperature of near-surface layers differs to a greater extent from the corresponding temperature for the mid-surface layers. The excess of the deformation temperature of the surface layers over the mid-surface layers depends on the stage of deformation of the sample material. At the end of the elastic stage of the specimen, the temperatures differ by 1.7 °C, and at the beginning of fracture with the formation of the neck, the excess of surface layer temperatures reached 4.5 °C. In specimens with lateral notches with a distance from the machine grip, the surface temperature did not change during loading. In the sections passing through the zone of scale delamination near the notches, the surface temperature in the middle part of the specimen is higher by 3.0–3.5 °C than in the vicinity. The maximum temperature of the metal surface during deformation reached 70 °C. It was found that the sections of the specimen adjacent to the notch in the process of deformation lose position stability, manifested in the change of the initial position to the deformed one. At the same time, the metal adjacent to the notch in the form of a prism with a triangular base and a height equal to the sheet thickness lost stability under the action of normal and tangential stresses. The metal in the prism volume was practically not deformed. The prism base temperature increased slightly only after the initiation of the notch crack.

Studies have implicated the importance of longwave (LW) cloud‐radiative forcing (CRF) in facilitating or accelerating the upscale development of tropical moist convection. While different cloud types are known to have distinct CRF, their individual roles in driving upscale development through radiative feedback is largely unexplored. Here we examine the hypothesis that CRF from stratiform regions has the greatest positive effect on upscale development of tropical convection. We do so through numerical model experiments using convection‐permitting ensemble WRF (Weather Research and Forecasting) simulations of tropical cyclone formation. Using a new column‐by‐column cloud classification scheme, we identify the contributions of five cloud types (shallow, congestus, and deep convective; and stratiform and anvil clouds). We examine their relative impacts on longwave radiation moist static energy (MSE) variance feedback and test the removal of this forcing in additional mechanism‐denial simulations. Our results indicate the importance stratiform and anvil regions in accelerating convective upscale development. Plain Language Summary: Infrared or longwave radiation and its interaction with clouds is important in the formation of tropical storms. Given the different shapes and distributions of distinct cloud types, we hypothesize that they interact with longwave radiation differently, and therefore exert different impacts on the organization of tropical convection. This issue has largely been unexplored. To address this gap, we tested our hypothesis by analyzing numerical model simulations of the formation of two tropical cyclones. Further, we developed a new cloud classification scheme based on cloud properties that identifies five distinct cloud types. Using this classification, we examined the impact of radiative interactions with different cloud types on the development of tropical storms by turning off this feedback in specific cloud types. Our results indicate that light‐raining regions, such as stratiform and anvil clouds, contribute dominantly to longwave cloud‐radiative trapping and the moistening of convective regions. This is due to both these cloud types' strong greenhouse trapping effect and their extensive areal coverage, which spreads this effect over large regions of a developing storm. Key Points: A new column‐by‐column cloud microphysical classification scheme is developed for application with numerical modelsRadiative feedback due to stratiform and anvil clouds is a leading driver of tropical convective upscale developmentThe local radiative forcing by deep convective regions is similar in magnitude to stratiform but its impact is limited by its smaller area [ABSTRACT FROM AUTHOR]

Greenhouses are used to create the appropriate environment for plant growth. Controlling the level of lighting using shading nets is one of the most commonly used methods for making suitable environmental modifications in greenhouses. The objective of this study was to examine the impact of three colored shading nets (green, black, and beige at shading rates of 50%) on inside air temperature, relative humidity, and spectral distribution of light in a greenhouse, as well as their effect on the growth and yield of strawberry plants. Data were collected during winter (December and January) and spring (March and April) months from shaded and unshaded blocks. The green net had the highest transmittance to solar radiation (τSR) during the two periods (38% and 35%, respectively) and the highest transmittance to photosynthetically active radiation (τPAR) of 34% during spring months, while the beige net had the highest τPAR of 27% during winter months. The black net had the smallest τPAR values during the two periods (22% and 29%, respectively). The lowest total light levels per season for solar radiation (SR) and photosynthetically active radiation (PAR) (746.8 and 293.7 MJ·m−2, respectively) were obtained under the black net, compared with (906.7 and 320.8 MJ·m−2, respectively) for the beige net, and (969.6 and 337.2 MJ·m−2, respectively) for the green net. The ratio of PAR to SR (PAR:SR) was 41% and 44% outside and inside the greenhouse for the control (without shade), respectively. The black net had the highest ratio of PAR:SR (39%) among the treatment nets. The green net transmitted more light in the blue–green region (400 to 570 nm) and transmitted the highest photon flux at 480 nm, while the beige net increased the infrared radiation flux from 730 nm and above and transmitted the highest photon flux at 604 nm. The study found that the green net increased the ratio of blue to red light (B/R), while the beige and green nets reduced the red to far-red light (R/FR) ratio. The photosynthetic rate, conductance to water, and transpiration were significantly higher for strawberries grown under the beige net. These results indicate that the beige net positively influenced leaf and stem characteristics, leading to improved strawberry yields. The best yields of strawberries were obtained under the beige net and the control group (no shade), surpassing the yields achieved under the black net by 26.3% and 21.4%, respectively. [ABSTRACT FROM AUTHOR]

Simple Summary: Signals generated from passing infrared radiation through biological samples such as serum can create distinct wave patterns, or "fingerprints", that can be used to distinguish samples with or without diseases such as osteoarthritis. In research, the collection of a large database of samples for studying diseases such as osteoarthritis can take years and requires the storage of samples in freezers. The aging of samples in the frozen state can change both the quality of samples and the results that are obtained from aged samples versus fresh, frozen samples. In this study, serum and joint fluid from dogs that had knee osteoarthritis and those that did not were used to compare the quality of the generated fingerprints from samples after short- and long-term storage in the frozen state. The results showed that even though aging of samples in the frozen state causes statistically significant differences between the fingerprint of samples, these changes only account for 2–3% of the overall variance in the spectroscopic data set (compared, e.g., to the variability stemming from differences between samples having been withdrawn from arthritic versus healthy dogs, which amounts to 77% for serum or even 86% for synovial fluid). The fingerprint of both serum and joint fluid samples after long-term storage of about seven years could still be used to distinguish between arthritic and healthy dogs with a high degree of accuracy. Mid-infrared spectral (MIR) patterns of serum and synovial fluid (SF) are candidate biomarkers of osteoarthritis (OA). The impact of long-term storage on MIR spectral patterns was previously unknown. MIR spectra of canine serum (52 knee-OA, 49 control) and SF (51 knee-OA, 51 control) were obtained after short-term and long-term storage in −80 °C. Multilevel simultaneous component analysis and partial least squares discriminant analysis were used to evaluate the effect of time and compare the performance of predictive models for discriminating OA from controls. The median interval of storage between sample measurements was 5.7 years. Spectra obtained at two time points were significantly different (p < 0.0001); however, sample aging accounted for only 1.61% and 2.98% of the serum and SF profiles' variability, respectively. Predictive models for discriminating serum of OA from controls for short-term storage showed 87.3 ± 3.7% sensitivity, 88.9 ± 2.4% specificity, and 88.1 ± 2.3% accuracy, while for long-term storage, they were 92.5 ± 2.6%, 97.1 ± 1.7%, and 94.8 ± 1.4%, respectively. Predictive models of short-term stored SF spectra had 97.3 ± 1.6% sensitivity, 89.4 ± 2.6% specificity, and 93.4 ± 1.6% accuracy, while for long-term storage they were 95.7 ± 2.1%, 95.7 ± 0.8%, and 95.8 ± 1.1%, respectively. Long-term storage of serum and SF resulted in significant differences in MIR spectral variables without significantly altering the performance of predictive algorithms for discriminating OA from controls. [ABSTRACT FROM AUTHOR]

High‐density polyethylene (HDPE) is largely processed using conventional manufacturing techniques. However, there is a need to investigate its processability when fabricated using additive manufacturing (AM) in an effort to use this polymer for high‐end applications, such as the fabrication of human implants. In this regard, the current study investigated the intrinsic and extrinsic properties of HDPE powders (DiaPow HDPE HX R) from Diamond Plastics GmbH, to determine its feasibility of use in powder bed fusion (PBF). Powder characterisation was undertaken using a scanning electron microscope (SEM), melt flow index (MFI) testing, tapped density testing, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier‐transform infrared (FTIR) spectroscopy, and hot‐stage microscopy. The analysis revealed that this high‐density polyethylene powder is suitable for processing using PBF based on the particle size distribution (PSD) (65–92 μm), flowability (Hausner ratio = 1.22 ± 0.02), melting point range (125.7–135.2 degrees Celsius), enthalpy of melting (170.51 J/g), and thermal stability (the materials starts to degrade at 350.0 degrees Celsius and completely degrades at 500.0 degrees Celsius). It also showed good coalescence behaviour. However, the narrow sintering window (7.9 degrees Celsius) of the material indicates possible challenges of shrinkage and curling during printing. The material was also found to have poor absorptive properties of infrared radiation at 10.6 μm, which might make sintering using CO2 lasers challenging. [ABSTRACT FROM AUTHOR]

In this paper, using laser direct writing technology, a femtosecond laser was used to process a periodic grating structure on a 99.99% tungsten target. The specific parameters of the laser are as follows: a center wavelength of 800 nm, pulse width of 35 fs, repetition rate of 1 kHz, and maximum single pulse energy of 3.5 mJ. The surface morphology of the samples was characterized and analyzed using a scanning electron microscope (SEM, Coxem, Republic of Korea) and atomic force microscope (AFM, Being Nano-Instruments, China). The thermal radiation infrared spectrum of the tungsten target with grating structures was measured using a Fourier transform infrared spectrometer (Vertex 70, Bruker, Germany). The results show that as the laser fluence increases, the depth of the groove, the width of the nanostructure region, and the width of the direct writing etching region all increase. The peak thermal radiation enhancement appears around the wavenumber of 900 cm−1 when the laser fluence is sufficient. Additionally, its intensity initially increases and then decreases as the laser fluence increases. If the grating period is too large, the impact on thermal radiation is not clear. The heating temperature significantly affects the intensity of thermal radiation but does not have a noticeable effect on the position of thermal radiation peaks. Moreover, the relative weighting of different wavenumbers changes as the temperature increases. [ABSTRACT FROM AUTHOR]

Twenty‐two years (2002–2023) of infrared radiative cooling rate data derived from the SABER instrument on the NASA TIMED satellite are presented. Global daily and global annual infrared power (Watts, W) emitted by nitric oxide (NO) and carbon dioxide (CO2) illustrate the variability of the geospace environment on timescales from days to decades. The 11‐year solar cycle (SC) is evident in the global power data and in vertical profiles of infrared cooling rates (nW/m3). The global annual power radiated by NO and CO2 are larger in 2023 than at any time since 2003 and 2002, respectively. The to‐date peak in NO infrared power in SC 25 is larger than in SC 24, is comparable to SC 20, but is less than in SCs 18–19 and 21–23. Two geomagnetic storms in 2023 radiated more than 1 TW and are in the top 10 strongest storms observed by SABER. Plain Language Summary: SABER is an instrument on the NASA TIMED satellite, launched in December 2001, and is still operating nominally in 2024. SABER measures the amount of infrared energy emitted by the nitric oxide (NO) molecule and the carbon dioxide (CO2) molecule from Earth's thermosphere, the region of atmosphere above 100 km altitude. These measurements are used to derive the amount of power (Watts) radiated globally by these two molecules on daily to annual timescales. The infrared power data is then analyzed to determine its variability in the lower thermosphere from daily to decadal time scales. Of particular interest is the influence of the well‐known 11‐year cycle of solar activity which is readily evident in the infrared power data. SABER also observes the effects of geomagnetic storms, identifying two strong storms in 2023 that each produced over 1 TW of infrared power. Key Points: SABER on TIMED has observed infrared radiation from the thermosphere since January 2002, for 22 years, the equivalent of two solar cyclesGlobal annual infrared power radiated by NO and CO2 are larger in 2023 than any time since 2003 and 2002, respectivelyTwo geomagnetic storms in 2023 exceeded 1 TW of radiated energy, above background, and are in the top 10 strongest storms observed [ABSTRACT FROM AUTHOR]

Time series of radiative cooling of the upper mesosphere and lower thermosphere (UMLT) by carbon dioxide (CO2) are examined for evidence of trends over 20 years. Radiative cooling rates in K day−1 provided by the SABER instrument are converted to time series of infrared power radiated from three distinct layers between 0.1 hPa and 0.0001 hPa (65–105 km). Linear regression against time and a predictor for solar variability provides estimates of the trend in exiting longwave radiation (ELR) from these layers. Trends in ELR are not significantly different from zero at 95% or 99% confidence in each layer. These results demonstrate energy conservation in the UMLT on decadal time scales and show that the UMLT continues to radiate the same amount of energy it receives despite cooling and contracting over two decades. These results are enabled by the long‐term stability of the SABER instrument calibration. Plain Language Summary: The Earth's upper mesosphere and lower thermosphere (UMLT) is the region between approximately 65 and 105 km in altitude. Infrared radiation emitted by CO2 is a fundamental component of the energy budget of the UMLT. Carbon dioxide (CO2) is increasing in this region. The amount of infrared energy emitted by CO2, over time, must balance the amount of energy from sunlight that is absorbed in the UMLT. Observations from orbiting satellites over the past two decades have shown that the temperature in the UMLT is decreasing due to the increasing CO2. A decreasing temperature implies a decrease in infrared energy emitted by an object. Energy conservation, however, requires that the amount of infrared energy radiated from the UMLT balance the amount of energy received, regardless of the temperature. In this paper we show that there is no significant long‐term change with time (i.e., zero trend) in the infrared energy emitted from the UMLT even though the UMLT temperature has been decreasing for the last 20 years (and longer) due to increasing CO2. This result confirms that energy is conserved in a cooling and contracting UMLT. Key Points: Time series of infrared power (W) radiated by CO2 from the upper mesosphere & lower thermosphere (UMLT) are developedTrends in radiated power are not different from zero at 95% or 99% confidence in the three layers examined between 0.1 and 0.0001 hPaIncreasing CO2 reduces the UMLT temperature while radiating the same amount of energy over time, thus conserving energy [ABSTRACT FROM AUTHOR]

Spinel‐structured high‐entropy oxides (HEOs), the novel materials, have recently attracted great attention for their unexpected properties and extensive applications. In this work, employing a facile scalability process of solid‐state reaction method, we synthesized a new kind of non‐equimolar (Co2/11Mn2/11Fe2/11Cr2/11Ni2/11Cu1/11)3O4 HEOs powder. However, under the same condition, the raw mixed oxide powders, with equimolar cations and higher configuration entropy, cannot form single‐phase HEOs powder but with the mixture of (Co,Mn,Fe,Cr,Ni,Cu)3O4 and residual CuO powders, ruling out the crucial role of entropy effect in forming single‐phase spinel‐structured HEOs. In addition to (Co2/11Mn2/11Fe2/11Cr2/11Ni2/11Cu1/11)3O4 powder, various (Co,Mn,Fe,Cr,Ni,Cu)3O4 HEOs powders can be obtained by controlling the Cu cation content in an appropriate range. To explore the application of the spinel‐structured HEOs in high‐temperature infrared field, the infrared radiation properties of the (Co2/11Mn2/11Fe2/11Cr2/11Ni2/11Cu1/11)3O4 powder were evaluated and exhibited a high‐infrared radiation emissivity of 0.880 in the near‐infrared wavelength range (0.78–2.5 µm) and superior thermal stability. Notably, the infrared radiation emissivity of the HEOs powder was maintained at 0.855 with a slight loss of 2.8% after high‐temperature treatment. This work not only provides a valuable strategy for fabricating high‐ and stable‐infrared radiation properties materials but also expands the great potential application of spinel‐structured HEOs to high‐temperature infrared field, such as energy saving in industrial high‐temperature furnaces. [ABSTRACT FROM AUTHOR]

To address the need for the accurate parameterization of radiative absorption by gasses (for predicting atmospheric warming), Chou et al. developed a new k-distribution method. In this study, we compared the improved k-distribution method (hereinafter referred to as the NEW method) with the New Goddard radiation schemes (hereinafter referred to as the OLD method) for the WRF (the weather research and forecasting) model. The results of radiative flux calculations by the NEW and OLD methods of k-distribution using the New Goddard Radiation Scheme were compared with the results of the line-by-line (LBL) method, and the results showed that the radiative flux calculated by the NEW was accurate to within 1.00 Wm−2 with respect to the LBL, while the OLD showed large differences at altitudes above the upper troposphere and near the surface. Therefore, in this study, we selected clear-sky and cloudy-day conditions and compared the weather elements prediction results of WRF using the NEW and OLD methods. For the clear-sky days, the downward shortwave radiation at the surface and the temperature at 2 m above the surface (hereinafter referred to as T2) over land and ocean were reversed in sign due to the highly sensitive absorption coefficients of gasses. For cloudy days, the absorption effect by gasses harmonized with the scattering effect induced by cloud droplets; the differences in the shortwave and longwave radiations and radiative heating rate between the NEW and OLD methods were obvious. Thus, it was analyzed that the proposed NEW method could lead to significant improvements in forecasting weather elements. [ABSTRACT FROM AUTHOR]

A type of nanocavity-shaped metasurface for intensively absorbing infrared (IR) radiation in a wide wavelength range of 3–14 μm, which is mainly based on spatial magnetic plasmon excitation and accumulation according to an arrayed nanocavity, is proposed. The basic architecture of the metasurfaces is a layered metal-insulator-metal construction through linear arranging of titanium microribbons and also forming an arrayed titanium microcap on the top of a SiO2 layer preshaped over a thin copper film grown on an n-type silicon wafer, respectively. The measurements present that an average IR absorbing efficiency of more than ∼80% can be easily realized by the metasurfaces constructed. The microribbon-based metasurface exhibits polarization sensitivity under x-polarized incidence. A polarization-independent IR absorption can be conducted through the microcap-based metasurface developed continuously. It should be noted that the proposed nanocavity-shaped metasurfaces can, thus, be featured by an intensive IR absorption essentially attributed to the spatial magnetic plasmon excitation and accumulation or a spatial magnetic field resonant superposition and temporary storage in the multiple nanocavities of the metasurfaces designed. [ABSTRACT FROM AUTHOR]

This paper proposes a method for determining the optimal parameters for the thermal testing of plant tissues of fruits and vegetables containing surface and subsurface defects in the form of areas of plant tissues with different thermophysical characteristics. Based on well-known mathematical models for objects of predominantly flat, cylindrical and spherical shapes containing flat, spherical and cylindrical regions of defects, numerical solutions of three-dimensional, non-stationary temperature fields were found, making it possible to measure the power and time of the thermal exposure of the sample surface to the radiation from infrared lamps using the finite element method. This made it possible to ensure the reliable detection of a temperature contrast of up to 4 °C between the defect and defect-free regions of the test object using modern thermal imaging cameras. In this case, subsurface defects can be detected at a depth of up to 3 mm from the surface. To determine the parameters of mathematical models of temperature fields, such as thermal conductivity and a coefficient of the thermal diffusivity of plant tissues, a new method of a pulsed heat flux from a flat heater is proposed; this differs in the method of processing experimental data and makes it possible to determine the required characteristics with high accuracy during the active stage of the experiment in a period not exceeding 1–3 min. [ABSTRACT FROM AUTHOR]

Infrared thermal imaging camera as a non-contact monitoring of the object to be measured is widely used in fire detection, driving assistance and so on. Although there are many related studies, there is a lack of research on the influence of fog or smoke on infrared imaging under different environmental temperatures. To address this shortcoming, The temperature of both the environment and the target in this experiment is controlled by PID technology. The smoke or fog environment is generated using a smoke cake or an ultrasonic fog machine. The temperature of the target was measured by infrared thermal imaging camera. It was observed that as the temperature of the environment increases, the measured temperature of the target also increases. However, the change in temperature is more pronounced in the fog environment compared to either the smoke environment or the normal environment. It has been found through research that environmental radiation causes temperature changes in fog droplets. Therefore, Infrared radiation is less affected in the smoke environment and more affected in the fog environment. Additionally, when the environmental temperature is close to the target's temperature, the infrared image becomes blurred. [ABSTRACT FROM AUTHOR]

Electrochromic smart windows can achieve controllable modulation of color and transmittance under an external electric field with active light and thermal control capabilities, which helps reduce energy consumption caused by building cooling and heating. However, electrochromic smart windows often rely on external power circuits, which greatly affects the independence and portability of smart windows. Based on this, an electrochromic smart window driven by temperature-difference power generation was designed and implemented. This smart window provides automatic and manual control of the reversible cycle of electrochromic glass from light blue to dark blue according to user requirements and changes in the surrounding environment, achieving adaptive adjustment of visual comfort and reducing energy consumption. The infrared radiation rejection (from 780 to 2500 nm) of the electrochromic smart window is as high as 77.3%, and its transmittance (from 380 to 780 nm) fluctuates between 39.2% and 56.4% with changes in working state. Furthermore, the temperature in the indoor simulation device with electrochromic glass as the window was 15 °C lower than that with ordinary glass as the window after heating with a 250 W Philips infrared lamp for ten minutes. After 2000 cycles of testing, the performance of the smart window was basically maintained at its initial values, and it has broad application prospects in buildings, vehicles, and high-speed rail systems. [ABSTRACT FROM AUTHOR]

Intelligent and diversified development of modern detection technology greatly affects the battlefield survivability of military targets, especially infrared, acoustic wave, and radar detection expose targets by capturing their unavoidable infrared radiation, acoustic wave, and electromagnetic wave information, greatly affecting their battlefield survival and penetration capabilities. Therefore, there is an urgent need to develop stealth-protective materials that can suppress infrared radiation, reduce acoustic characteristics, and weaken electromagnetic signals. Fibrous three-dimensional porous materials, with their high porosity, excellent structural adjustability, and superior mechanical properties, possess strong potential for development in the field of stealth protection. This article introduced and reviewed the characteristics and development process of fibrous three-dimensional porous materials at both the micrometer and nanometer scales. Then, the process and characteristics of preparing fibrous three-dimensional porous materials through vacuum forming, gel solidification, freeze-casting, and impregnation stacking methods were analyzed and discussed. Meanwhile, their current application status in infrared, acoustic wave, and radar stealth fields was summarized and their existing problems and development trends in these areas from the perspectives of preparation processes and applicability were analyzed. Finally, several prospects for the current challenges faced by fibrous three-dimensional porous materials were proposed as follows: functionally modifying fibers to enhance their applicability through self-cross-linking; establishing theoretical models for the transmission of thermal energy, acoustic waves, and electromagnetic waves within fibrous porous materials; constructing fibrous porous materials resistant to impact, shear, and fracture to meet the needs of practical applications; developing multifunctional stealth fibrous porous materials to confer full-spectrum broadband stealth capability; and exploring the relationship between material size and mechanical properties as a basis for preparing large-scale samples that meet the application's requirement. This review is very timely and aims to focus researchers' attention on the importance and research progress of fibrous porous materials in the field of stealth protection, so as to solve the problems and challenges of fibrous porous materials in the field of stealth protection and to promote the further innovation of fibrous porous materials in terms of structure and function. [ABSTRACT FROM AUTHOR]

Highlights: A multifunctional Janus film is fabricated by integrating highly-crystalline and oxidation-resistant Ti3C2Tx MXene with carbon nanotube (CNT) film through strong hydrogen bonding, which exhibits high electrical conductivity of 4250 S cm−1 and robust mechanical strength of 77 MPa. The MXene/CNT Janus film of 15 μm thickness demonstrates efficient electromagnetic interference shielding of 72 dB, low infrared (IR) emissivity of 0.09 and hence superior thermal camouflage performance, and outstanding IR detection capability, while maintaining its integrity equally at room temperature as well as under extreme conditions. This multifunctional MXene/CNT Janus film offers a practical solution for electromagnetic shielding and IR shielding/detection in challenging conditions. Multifunctional, flexible, and robust thin films capable of operating in demanding harsh temperature environments are crucial for various cutting-edge applications. This study presents a multifunctional Janus film integrating highly-crystalline Ti3C2Tx MXene and mechanically-robust carbon nanotube (CNT) film through strong hydrogen bonding. The hybrid film not only exhibits high electrical conductivity (4250 S cm−1), but also demonstrates robust mechanical strength and durability in both extremely low and high temperature environments, showing exceptional resistance to thermal shock. This hybrid Janus film of 15 μm thickness reveals remarkable multifunctionality, including efficient electromagnetic shielding effectiveness of 72 dB in X band frequency range, excellent infrared (IR) shielding capability with an average emissivity of 0.09 (a minimal value of 0.02), superior thermal camouflage performance over a wide temperature range (− 1 to 300 °C) achieving a notable reduction in the radiated temperature by 243 °C against a background temperature of 300 °C, and outstanding IR detection capability characterized by a 44% increase in resistance when exposed to 250 W IR radiation. This multifunctional MXene/CNT Janus film offers a feasible solution for electromagnetic shielding and IR shielding/detection under challenging conditions. [ABSTRACT FROM AUTHOR]

Objectives: Olmesartan medoxomil (OLM) is a low bioavailability antihypertensive drug. This study aimed to prepare and optimize an OLM niosomal gel and investigate drug permeation via a chicken buccal pouch. Materials and Methods: OLM-loaded niosome were prepared using a film hydration technique. The vesicle size, zeta potential, entrapment efficiency, and percentage cumulative drug release of niosome were evaluated. The niosomes were incorporated into a Carbopol 974P (1.5% w/v) gel, and the drug permeability of the niosomal gel was evaluated. The formulations of the niosomal gel were optimized using the Box-Behnken design. The optimized formulation was further characterized by transmission electron microscopy (TEM) and Fourier transform infrared radiation analysis. Results: The particle size and zeta potential of the optimized niosomal formulations were 296.4 nm and -38.4 mV, respectively. Based on TEM analysis, the niosomes were found to be spherical in shape. The permeability, flux, and permeability coefficient of the optimized niosomal gel were 0.507 mg/cm2, 0.083 mg/cm2 × hour, and 041 cm/hour, respectively. Histopathological evaluation revealed that the niosomal gel had better permeability than the OLM gel. Conclusion: Based on the results of the OLM niosomal gel, it can be concluded that the formulation can be beneficial in increasing bioavailability, resulting in better therapeutic efficacy. [ABSTRACT FROM AUTHOR]

The objective of this study is to create a planar solar light absorber that exhibits exceptional absorption characteristics spanning from visible light to infrared across an ultra-wide spectral range. The eight layered structures of the absorber, from top to bottom, consisted of Al2O3, Ti, Al2O3, Ti, Al2O3, Ni, Al2O3, and Al. The COMSOL Multiphysics® simulation software (version 6.0) was utilized to construct the absorber model and perform simulation analyses. The first significant finding of this study is that as compared to absorbers featuring seven-layered structures (excluding the top Al2O3 layer) or using TiO2 or SiO2 layers as substituted for Al2O3 layer, the presence of the top Al2O3 layer demonstrated superior anti-reflection properties. Another noteworthy finding was that the top Al2O3 layer provided better impedance matching compared to scenarios where it was absent or replaced with TiO2 or SiO2 layers, enhancing the absorber's overall efficiency. Consequently, across the ultra-wideband spectrum spanning 350 to 1970 nm, the average absorptivity reached an impressive 96.76%. One significant novelty of this study was the utilization of various top-layer materials to assess the absorption and reflection spectra, along with the optical-impedance-matching properties of the designed absorber. Another notable contribution was the successful implementation of evaporation techniques for depositing and manufacturing this optimized absorber. A further innovation involved the use of transmission electron microscopy to observe the thickness of each deposition layer. Subsequently, the simulated and calculated absorption spectra of solar energy across the AM1.5 spectrum for both the designed and fabricated absorbers were compared, demonstrating a match between the measured and simulated results. [ABSTRACT FROM AUTHOR]

The utilization of CO2 mineralization fly ash (F) and coal gangue (G) technology is proposed in this research work to prepare underground backfilling materials. The test process can be divided into pre-treatment and post-treatment stages. In the pre-treatment stage, a sealed stirring vessel is used to conduct CO2 wet mineralization. The ratios of F and G were selected as follows: 20%:60% (F2G6), 30%:50% (F3G5), 40%:40% (F4G4), 50%:30% (F5G3), and 60%:20% (F6G2). The ratios were prepared into Φ50 mm × 100 mm cylindrical samples, with curing durations of 3 d, 7 d, 14 d, and 28 d. In the post-processing stage, the SANS microcomputer-controlled electronic universal testing machine and FLIR A615 infrared thermal imager were used to carry out uniaxial loading and temperature detection, respectively. The unconfined compressive strength (UCS), X-ray diffraction (XRD), average infrared radiation temperature (AIRT), variance of original infrared image temperature (VOIIT), and variance of successive minus infrared image temperature (VSMIT) of the samples were compared and analyzed. The results indicated that when curing reaches 14 d, the strength approaches its peak, with minimal changes in strength over a delayed period; furthermore, as the ratio of F to G continues to increase, the mineralization effect gradually strengthens, reaching its optimum level at a ratio of 5:3. However, when the ratio exceeds 5:3, signs of deteriorating mineralization effect start to appear. During the loading process, the AIRT of the mineralized samples showed a continuous increase, but the VOIIT and VSMIT of the mineralized sample both exhibited significant fluctuations or rapid increases during damage rupture. Moreover, the rise in the AIRT value was found to be linked to the increase in the ratio of F to G. This indicates that F has a higher thermal–mechanical conversion efficiency compared to G, so the temperature change will be greater during the loading process. The drastic changes in the VOIIT and VSMIT indicate that they can be used as sensitive response indicators for sample rupture, and can predict and warn of damage rupture in mineralized samples. Research work can provide practical guidance and reference for underground backfilling of CO2 mineralization industrial waste. [ABSTRACT FROM AUTHOR]

The emission of infrared radiation from objects of investigation provides a viable non-contact imaging mode through thermal imaging which is a motivation to conduct thermal imaging experiments on seeds for assessing the quality of paddy seeds. It consisted of seed collection, segregation, sample preparation, thermal imaging, and analysis besides test of germination for comparison. We collected paddy seeds from local seed distributors and segregated them into low, medium, and high-quality seeds based on their physical characteristics. Then, the seeds were kept in moistened filter paper, dried, and placed over a petri dish. Next, seeds of a particular quality in a petri dish were under irradiation of a halogen lamp for 40 seconds followed by a video recording of the emission of samples using an infrared thermal imaging camera for a period of 60 seconds. We could collect and carefully tabulate emission temperatures of the sample of each quality for every 10 seconds using the video image. Finally, the sample time-temperature plot has shown that a higherquality seed radiates at higher temperature (39°C to 33.9°C) than low-quality seeds (36.9°C to 32.8°C). In order to compare the behavior of IR thermal emission of paddy seeds, a preliminary study of germination test was conducted which has shown that germination (%) in CO 50 seeds is higher than ADT 42 seeds and variation of seedling emergence among the seeds. In conclusion, the current research suggests that infrared thermal imaging techniques may be considered to assess the quality of the seeds, however, it requires confirmation with more experiments on various paddy samples. [ABSTRACT FROM AUTHOR]

Developing high-performance infrared radiation ceramic materials with desired broadband emissivity while reducing thermal conductivity to prevent heat transfer is highly desirable for emerging industrial and aerospace applications. Nevertheless, it remains a grand challenge to simultaneously meet these requirements in existing infrared radiation ceramic materials. Herein, a high-entropy strategy is employed to enhance the high-temperature infrared radiation property with a high emissivity above 0.9 at room temperature and 0.68 at 1200 °C across the entire range of wavelength (1–14 μm), and integrate a low thermal conductivity (<0.88 W m−1 K−1 at 1000 °C) and remarkable mechanical properties. High-entropy rare earth (RE) disilicates ((Y 0.4 Yb 0.4 Tm 0.1 Lu 0.05 Ho 0.05) 2 Si 2 O 7) ceramic coating with high lattice entropy has a more complex electronic structure, inducing lattice distortion and extra multi-mode vibrations, which boosts the emissivity in mid-infrared range (3–14 μm). Meanwhile, the high-entropy strategy prompts the formation of impurity energy levels as gap states, achieving optical absorption at low photon energies, and thus enhancing the emissivity in near-infrared range (1–3 μm). Simultaneously, (Y 0.4 Yb 0.4 Tm 0.1 Lu 0.05 Ho 0.05) 2 Si 2 O 7) ceramic coating owns diffusion-mediated thermal transport properties with strong phonon scattering, assisted further by the lamellar porous structure, thereby enabling a low thermal conductivity. The excellent mechanical properties ensure the reliability of the coating in extreme environments. All these merits render the high-entropy ceramic coating competitive for the development of high-temperature broadband high-emissivity thermal radiation materials. [ABSTRACT FROM AUTHOR]