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In this paper, we examined the effects of proximity-induced interactions such as Rashba spin-orbit coupling and effective Zeeman fields (EZFs) on the optical spectrum of n -type and p -type monolayer (ML)-MoS 2. The optical conductivity is evaluated using the standard Kubo formula under random-phase approximation by including the effective electron–electron interaction. It has been found that there exist two absorption peaks in n -type ML-MoS 2 and two knife shaped absorptions in p -type ML-MoS 2 , which are contributed by the inter-subband spin-flip electronic transitions within conduction and valence bands at valleys K and K ′ with a lifted valley degeneracy. The optical absorptions in n -type and p -type ML-MoS 2 occur in THz and infrared radiation regimes and the position, height, and shape of them can be effectively tuned by Rashba parameter, EZF parameters, and carrier density. The interesting theoretical predictions in this study would be helpful for the experimental observation of the optical absorption in infrared to THz bandwidths contributed by inter-subband spin-flip electronic transitions in a lifted valley degeneracy monolayer transition metal dichalcogenides system. The obtained results indicate that ML-MoS 2 with the platform of proximity interactions make it a promising infrared and THz material for optics and optoelectronics. [ABSTRACT FROM AUTHOR]

In this study, we introduce a theoretical model designed to explore both the photochemical and photothermal behavior of arc plasma radiation-induced ablation in gassing materials. We employ time-dependent density functional theory to analyze the photochemical behavior, while reactive force field molecular dynamics are used to explore the photothermal behavior. The phenomena, behavior and consequences of valence shell electronic excitation are analyzed in terms of ultraviolet (UV) absorption, electron-hole distribution, and Mayer bond order. Based on the photochemical findings, we apply a periodic electric field that corresponds to the vibration frequency of the permanent dipole moment to simulate infrared radiation, and convert UV photon energy into atomic kinetic energy to analyze UV radiation. This atomic-scale insight into photothermal behavior enables us to identify the final composition of ablation gases, including H2, CO, H2O, NH3, as well as specific cyanides, amines, and hydrocarbons. The results of the theoretical model and physical properties indicate that the concentration of hydrogen-containing gases in the ablation gas significantly affects the arc extinguishing capabilities of different polymers. Finally, we propose modification schemes suitable for polymers in power circuit breakers, considering UV absorption and smoke black production. Additionally, we present the potential application of theoretical models for calculating the ablation rate, necessitating further in-depth re-search. [ABSTRACT FROM AUTHOR]

Thermal imaging is crucial in surveillance, transportation safety, defense, search and rescue, industrial maintenance, manufacturing quality control, and firefighting for enhanced situational awareness. Yet, its effectiveness diminishes in adverse weather like fog, haze, rain, and poor lighting. However, its efficacy is often compromised in challenging environments characterized by adverse weather conditions such as fog, haze, rain, and poor lighting. This paper proposes an image enhancement framework using Wavelet Transform to improve thermal imaging in challenging conditions. It decomposes images into frequency components, selectively enhancing low and high-frequency details. A kurtosis-based histogram clipping algorithm enhances contrast and visibility in low-frequency components. Synthesizing components using inverse discrete wavelet transform produces the final image. The proposed methodology is evaluated using publicly available datasets, including OSU thermal and AAU rain-snow datasets, to evaluate its performance in various challenging scenarios with quantitative metrics like Entropy, Absolute Mean Brightness Error (AMBE), Peak Signal Noise Ratio (PSNR), and Structural Similarity Index (SSIM) are employed for a comprehensive analysis of the proposed Wavelet Transform-based approach. The results demonstrate image quality and visibility improvements, positioning the proposed framework as a promising solution for enhancing thermal imaging in challenging environments and extending its applicability in critical real-world scenarios. [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]

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]

How to maximize the extraction of heat by infrared radiation while reducing the thermal conductivity to prevent heat transfer is the main challenge of radiative thermal management for emerging industrial and aerospace applications. Herein, we reported a high-temperature broadband high emissivity (Y 0.5 Lu 0.5) 2 SiO 5 ceramic with emissivity above 0.9 at room temperature and above 0.61 at elevated temperature of 1200℃ across the entire range of wavelength (1–14μm). Lu-doped rare earth monosilicate with high lattice entropy has a more complex electronic structure, boosting the emissivity of near-infrared wavelength (1–3 μm), as well as enhanced emissivity in the MIR range (3–14 μm) is derived from the lattice distortion and extra multi-mode vibrations induced by the substitutional doping of Lu3+ into the host lattice. Moreover, based on Stephen-Boltzmann law and energy conservation law found that the emissivity of rare earth monosilicate-based ceramics is negatively correlated with temperature, which may be due to the fact that rising temperature increases damping of phonon vibration of the ceramic lattice, reducing the ability of infrared absorption. This doped rare earth monosilicate ceramic has a high emissivity at high temperatures above 1200 °C, revealing immense potential in the radiation thermal protection field. [ABSTRACT FROM AUTHOR]

Soybean is a source of high-quality vegetable protein and a suitable substitute for meat protein. However, several factors, including a lengthy cooking process, palatability issues, and digestion concerns, have limited their consumption. Several treatments have been suggested to overcome such issues, including infrared heating, which has many advantages over traditional roasting methods. In this study, the three-dimensional microstructure of soybeans with initial moisture contents (12, 16, 20, and 24% w.b.) and treated at different micronization durations (60, 90, and 120 s) at 180 °C were studied and related to quality parameters including water absorption and hardness of both non-cooked and cooked samples. The water absorption tests demonstrated no significant difference (p > 0.05) between the moisture absorbed for 60, 90, and 120 s micronization with initial moisture levels of 12, 16, and 24%. Yet all soybeans treated for 60 s exhibited significantly different results (p < 0.05) compared to raw counterparts. The highest hardness values were achieved after 60 s treatments on 24% moisturized seeds. As expected, the 20 min cooking time resulted in a considerable reduction in soybean hardness. The X-ray micro-computed tomography (micro-CT) was a powerful non-destructive tool to explore the microstructure of individual soybean seeds. Results of X-ray micro-CT have shown an increase in open porosity with increasing infrared treatment time. Overall, the qualitative and quantitative analysis provided in this study may serve as a basis for developing improved food processing techniques. [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]

Enhancement of the light-absorption response and utilization of the photogenerated carriers represent a robust strategy for the design of high-performance photocatalyst. In this work, grafting CoxP nanoclusters onto S-scheme heterojunction of W18O49/ZnIn2S4 (WO/ZIS-CoxP) with strong response to the ultraviolet–visible–near infrared ray (UV–vis–NIR) region has been achieved, which possesses efficient electron-transfer-channel, and boosts charge-separation and transport kinetics. The as-prepared WO/ZIS-CoxP yields an impressive solar-driven hydrogen production rate of 45 mmol·g−1·h−1. The increased photocatalytic performance is attributed to the synergistic effect of the composite catalyst: (1) The local surface plasmon resonance-induced "hot electron" injection of W18O49 significantly increases the electron density; (2) the engineered S-scheme directional electron transfer promotes charge separation and enhances the reducing capability of photoexcited electrons; and (3) CoxP as electron-trap site for accelerating surface proton reduction reaction. This work provides a platform to impart nonprecious co-catalyst for engineering S-scheme heterojunction, serving a class of efficient solar-driven photocatalyst towards hydrogen production. [ABSTRACT FROM AUTHOR]

BACKGROUND: Energy‐saving and low‐carbon baking processes, as well as the need to determine the flavor‐forming mechanisms of baked dried tofu, are becoming increasingly necessary. The application of emerging catalytic infrared radiation (CIR) technology in baking of dried tofu is considered of high interest due to the low energy consumption and high baking efficiency compared to traditional baking methods. Hence, this study aimed to investigate the evolution of aroma compounds in baked dried tofu during the CIR baking process and reveal relevant relationships between physical qualities, potential flavor precursors and key volatile compounds. RESULTS: The results showed that the surface color of dried tofu gradually turned an appetizing golden yellow color during the rapid heating process, caused by the uniform infrared radiation from the radiant emitters. Meanwhile, the moisture of dried tofu experienced minimal reduction and the hardness of dried tofu gradually increased with the formation of crust on the surface. In addition, 49 volatile compounds were identified by headspace solid‐phase microextraction–gas chromatography–mass spectrometry and 13 substances – 1‐hexanol, 1‐octen‐3‐ol, 1‐pentanol, heptanal, nonanal, hexanal, (E,E)‐2,4‐decadienal, (E,Z)‐2,4‐decadienal, octanal, (E)‐2‐octenal, (E)‐2‐nonenal, 2‐heptanone and 2‐pentylfuran – were confirmed as key aroma compounds. Moreover, the amino acids aspartic acid, glutamic acid, isoleucine, lysine and arginine, and the fatty acids butyric, caprylic, capric, tridecanoic, stearic, oleic and linolenic were responsible for the unique flavor of CIR‐baked dried tofu. CONCLUSION: Consequently, the findings can provide a scientific basis for manufacturers to achieve precise quality control and large‐scale production of CIR‐baked dried tofu products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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]

Antarctic warm extremes impact the cryosphere, with very warm extremes driving surface melt on ice shelves. Here, we analyze temperatures exceeding the 90th percentile and the associated circulation patterns and radiation anomalies. ERA5 reanalysis data show positive geopotential height anomalies related to the occurrence of warm extremes. The highest temperature during warm extremes appears on the western periphery of high‐pressure systems, consistent with anticyclonic advection. Temperature anomalies during warm extremes are strongest in winter due to the transport of warm and moist air and a strong meridional temperature gradient. In summer, the weak meridional gradients of top‐of‐atmosphere downward solar radiation flux and surface air temperature contribute to weak temperature anomalies. Warm extremes are associated with positive longwave radiation anomalies in all seasons, but with negative shortwave radiation anomalies at the surface except during polar night. These relationships are verified by station observations. Our results confirm that Antarctic warm extremes are mostly driven by meridional advection of warm air, and suggest that these warm air masses are predominantly moist and cloudy. Plain Language Summary: Changes in Antarctic climate will alter the amount of water stored in the kilometer‐thick Antarctic ice cover, and thereby global sea level. So far, only some regions of the continent have experienced substantial warming under climate change, while others remain largely unaffected. In this study, we analyze the relatively warmest Antarctic temperatures in each place and season. We find that these warm extremes depart more strongly from seasonal mean temperatures in winter than in summer. Warm extremes are often a consequence of warmer air being transported from further North and coincide with moist, probably cloudy air that emits more infrared radiation to the surface than dry, cold air. Key Points: Warm extremes accompanied by high‐pressure systems are driven by advectionWinter experiences strongest temperature anomalies during warm extremesLongwave radiation anomalies during warm extremes are positive and contribute to warm extremes, shortwave radiation anomalies are negative [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]

To study the efficacy of low-level laser therapy in the management of temporomandibular joint arthralgia. Design Interventional study (pre-post study), Setting Meenakshi Medical College And Hospital, Research Institute. Subjects 50 patients with temporomandibular joint arthralgia were evaluated for pain, mouth opening and clicking sound while mouth opening before and after treatment. Method Patients are subjected to undergo low-level laser therapy with Infrared and red rays with a therapeutic dosage ranging from 8 J/cm2 to 15 J/cm2 up to 3–5 sessions for a month each session lasts for 15–20 min. The patients are to be followed up regularly after 1, 3, 6 and 8 months in the study.The study measured the range of mouth opening in patients before and after undergoing low-level laser therapy. Before treatment, the range of mouth opening was from 2.78 to 3.97 cm, with a mean value of 2.78 cm and a standard deviation of 0.22. After treatment, the range of mouth opening was from 2.78 to 3.97 cm, with a mean value of 3.97 cm and a standard deviation of 0.24. The study also measured the VAS score for pain, with a mean and standard deviation of 7.9 ± 0.73 before treatment and 0.88 ± 0.718 after treatment. There was a significant difference between the pretreatment and post-treatment VAS scores, with a P-value of 0.05. Low-level laser therapy is an effective non invasive treatment modality for temporomandibular joint arthralgia. The patients who underwent this procedure had symptomatic relief and no remissions were observed. [ABSTRACT FROM AUTHOR]

Cosmic very small dust grains (VSGs) contain 100 to 10000 atoms, making them a mesoscopic system with specific thermal and optical characteristics due to the finite number of atoms within each grain. This paper focuses on graphite VSGs which contain free electrons. The energy level statistics devised by Kubo (1962 , J. Phys. Soc. Jpn. 17, 975) are used for the first time to understand the thermal properties of free electrons in graphite VSGs. We show that the shape irregularity of the grains allows graphite VSGs to absorb or emit photons at submillimeter wavelengths or longer; otherwise, the frequency is limited to above a few THz. Additionally, we consider the decrease in Debye temperature due to the surface effect. VSGs have an extremely small volume, resulting in limited thermal energy storage, especially at low temperatures. Since a VSG is able to emit a photon with energy smaller than its internal energy, this determines the maximum frequency of the emitted photon. We develop a Monte Carlo simulation code to track the thermal history of a dust grain, considering the stochastic heating from the absorption of ambient photons and radiative cooling. This approach is applied to the interstellar environment to compute the spectral energy distributions from the interstellar graphite dust grains. The results show that graphite VSGs emit not only the mid-infrared excess emission, but also a surplus emission from submillimeter to millimeter wavelengths. [ABSTRACT FROM AUTHOR]

A radiative cooling window is a type of energy-saving windows which is designed to emit radiation in the infrared atmospheric transparency window, while reflecting near-infrared light and transmitting visible light. Several radiative cooling windows based on film structures have been proposed, but the transmissivity of visible light or the reflectivity of near-infrared light needs to be improved. In this paper, a radiative cooling window with stacked multilayer structure is proposed. The film thickness and period number of SiO2/SiN periodic multilayer in the stacked structure are simultaneously optimized using genetic algorithm. Then the optimized stacked multilayer contain different periodic multilayer are also compared, and the spectral characteristic of the optimized stacked multilayer structure is further analyzed. An emissivity of 81% within the atmospheric window, a near-infrared reflectivity of 92% and a visible light transmissivity of 88% are obtained. Furthermore, the cooling performance of proposed stacked multilayer is studied, and a temperature drop of 32.2 K is realized when comparing it with a glass window with equal thickness. The proposed stacked multilayer structures could be used in radiative cooling windows for energy-saving of buildings and cars. [ABSTRACT FROM AUTHOR]

In order to explore the influence of the infrared stealth technology on the performance of the integrated helicopter/engine system, an integrated modeling method of helicopter/engine/infrared suppressor is proposed. Firstly, based on the power calculation model of the helicopter, combined with the high-precision turboshaft engine component-level model, an integrated simulation platform is built, which takes into account the nonlinear characteristics. Then, the aerodynamic characteristics of infrared suppressors under different engine operation states are studied by CFD numerical computation method, and the infrared radiation characteristics are obtained through combining the positive and negative ray tracing method and narrow band model method. Ultimately, the utilization of the power turbine outlet stagnation pressure is employed as the pivotal interface linking the turboshaft engine and the infrared suppressor in order to formulate an integrated model encompassing the helicopter, engine, and infrared suppressor subsystems. The simulation results demonstrate that compared with the conventional exhaust system, the application of the infrared suppressor greatly enhances the stealth performance of the helicopter, but also results in the unexpected decrease in engine output power. Moreover, the specific fuel consumption of the turboshaft engine increase and the compressor surge margin decreases in case of the consistent flight condition. [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]

In recent years, studies have shown that low‐dose supplemental infrared (IR) irradiation exhibits systemic anti‐inflammatory effects. The gut microbiota is increasingly recognized as a potential mediator of these effects due to its role in regulating host metabolism and inflammatory responses. To investigate the role of gut microbiota diversity and metabolite changes in the mechanism of light‐emitting diodes (LED) infrared's anti‐inflammatory action, we conducted IR irradiation on mice. Serum inflammatory cytokines were measured using ELISA, and fecal samples were subjected to metagenomic, untargeted, and targeted metabolomic analyses. Our results demonstrated a significant increase in the anti‐inflammatory cytokine IL‐10 in the IR group, accompanied by a declining trend in pro‐inflammatory cytokines. Gut microbiome analysis revealed distinct alterations in composition and functional genes between the groups, including the enrichment of beneficial bacteria like various species of Parabacteroides and Akkermansia muciniphila in the IR group. Notably, the IR group exhibited enrichment in carbohydrate metabolism pathways and a reduction in DNA damage and repair pathways. Furthermore, targeted metabolomic analysis highlighted a notable increase in short‐chain fatty acids (SCFAs), including butyric acid and isobutyric acid, which positively correlated with the abundance of several beneficial bacteria. These findings suggest a potential interplay between gut microbiota‐derived SCFAs and the anti‐inflammatory response. In conclusion, our study provides comprehensive insights into the changes in gut microbiota species and functions associated with IR irradiation. Moreover, we emphasize the significance of altered SCFAs levels in the IR group, which may contribute to the observed anti‐inflammatory effects. Our findings contribute valuable evidence supporting the role of low‐dose infrared light irradiation as an anti‐inflammatory therapy. [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]

Radiophotothermal therapy is a promising treatment for superficial tumors. Traditional radiotherapy requires tissue boluses on the patient's skin to increase therapeutic effectiveness due to the dose‐buildup effect of high‐energy radiation. However, combining radiotherapy with photothermal therapy leads to uncertainties as the low‐penetration near‐infrared light dose is reduced after penetrating the bolus. To enhance precision and effectiveness, this study introduces a novel bolus made of AuNPs@poly(AM‐THMA‐DMAEMA) composite hydrogel. This hydrogel is prepared through a one‐pot method involving the reduction of trihydrate chloroauric acid (HAuCl4·3H2O) and copolymerization of acrylamide (AM) and N‐[Tris(hydroxymethyl)methyl]acrylamide (THMA) in a redox system with dimethylaminoethyl methacrylate (DMAEMA) and potassium persulfate (KPS). The gold nanoparticles (AuNPs) improve the mechanical strength (tensile strength of 320.84 kPa, elongation at break of 830%) and antibacterial properties (>99% against Staphylococcus aureus). The local surface plasmon resonance (LSPR) effect of AuNPs enables the hydrogel to absorb near‐infrared light for precise monitoring of the infrared radiation dose. The hydrogel's biocompatibility is enhanced by the absence of additional crosslinking agents, and its excellent surface adhesion strength is due to numerous hydrogen bonds and electrostatic interactions. This study offers new possibilities for nanoparticle composite hydrogels as tissue boluses, achieving high precision and efficiency in radiophotothermal therapy. [ABSTRACT FROM AUTHOR]

We demonstrate a free-space amplitude modulator for mid-infrared radiation (λ ≈ 9.6 μm) that operates at room temperature up to at least 20 GHz (above the −3 dB cutoff frequency measured at 8.2 GHz). The device relies on the ultrafast transition between weak- and strong-coupling regimes induced by the variation of the applied bias voltage. Such transition induces a modulation of the device reflectivity. It is made of a semiconductor heterostructure enclosed in a judiciously designed array of metal–metal optical resonators, that—all-together—behave as an electrically tunable surface. At negative bias, it operates in the weak light–matter coupling regime. Upon application of an appropriate positive bias, the quantum wells populate with electrons, and the device transitions to the strong-coupling regime. The modulator transmission remains linear with input radio frequency power in the 0–9 dBm range. The increase in optical powers up to 25 mW exhibit a weak beginning of saturation a little bit below. [ABSTRACT FROM AUTHOR]

The ongoing advancements and growing adoption of infrared detection technology have spurred a tremendous amount of interest in thermal camouflage technology. Various approaches are employed to develop infrared camouflage materials capable of manipulating emissivity or surface temperature. However, the range of thermal radiation regulation implemented by these materials is still somewhat limited. In this paper, a combined emissivity and temperature regulation strategy that integrates a thermoelectric device (TED) and a thermochromic structure is proposed. By utilizing this strategy, it becomes possible to simultaneously control the surface temperature and the emissivity without needing additional complex excitation. As a concept demonstration, large tunabilities of 0.38 for long‐wave infrared (8–14 µm) emittance and 87 °C for surface temperature are observed, resulting in a prominent tunability of the thermal radiation temperature that is 15.4 °C greater than that of a conventional TED with constant emissivity. This work aims to introduce a new design paradigm for future thermal radiation management and camouflage techniques. [ABSTRACT FROM AUTHOR]

Purpose: Protocol description for renal perfusion study using thermographic technology and description of the thermographic and clinical behavior of the transplanted kidneys before and after unclamping. Methods: Infrared thermographic images of renal grafts are obtained before kidney reperfusion, 10 min after and just before closing the surgical wound. Thermographic data is evaluated together with the type of graft and donor, cold ischemia time, hypovascularized areas determined by the surgeon during surgical intervention, alterations in vascular flow in postoperative echo-Doppler, time at the beginning of graft function and serum creatinine monitoring during postoperative follow-up. Results: 17 grafts were studied. The mean temperature of the grafts before reperfusion, 10 min after and at the end of the surgery were 18.7 °C (SD 6.27), 32.36 °C (SD1.47) and 32.07 °C (SD1.78) respectively. 4 grafts presented hypoperfused areas after reperfusion. These areas presented a lower temperature compared to the well perfused parenchyma surface using thermographic images. Conclusion: The study of the usefulness and applicability of thermography can allow the development of tools that provide additional objective information on organ perfusion in real time and non-invasive manner. Our protocol and initial results can contribute to provide new evidence. Further analyses should be developed to shed light on the role of this technology. [ABSTRACT FROM AUTHOR]

The porous nature and gel network of aerogel fibers make them ideal options for personal thermal management because they can significantly cut down on energy waste. However, aerogel fibers generally suffer from poor mechanical properties and single function. Herein, the porous continuous bacterial cellulose/graphene oxide@polydopamine core–shell aerogel fibers with high strength, excellent photothermal properties, and thermal insulation are investigated by wet spinning and freeze‐drying. The bacterial cellulose/graphene oxide@polydopamine aerogel fiber prepared by wet spinning method has a porous structure, which can prevent heat convection, reduce heat conduction, and suppress heat radiation, making the aerogel fiber have excellent thermal insulation properties. More crucially, graphene oxide may considerably enhance infrared radiation's capacity for heating, while polydopamine can enhance ultraviolet light absorption and boost photothermal conversion capability. [ABSTRACT FROM AUTHOR]

Mid‐infrared (MIR) lasers generated by nonlinear optical (NLO) crystals have aroused extensive attention in various military and civilian applications. Among the MIR NLO crystal family, LiInSe2 (LISe) is a promising candidate in the generation of MIR lasers due to its wide transmission range, large bandgap, and high laser‐induced damage threshold. However, the intrinsic defects in LISe induce optical losses, which will induce laser damage and hinder the performance of MIR laser generation. In this work, the mechanism of optical absorption induced by defects is revealed in LISe through transient absorption (TA) spectroscopy. It is verified that the deep‐level defects in LISe give rise to the extra optical absorption, which is owing to the excited state absorption (ESA) and photo‐induced absorption (PIA). Accordingly, for improving the optical properties of LISe crystals, Li2Se vapor‐mediated annealing to reduce defects concentration is rationally designed. The results confirmed that the optical properties of annealed LISe are improved due to the decrease of defects concentration. Ultimately, the performance of MIR laser generation is successfully enhanced by using the annealed LISe crystal. This work provides deep insights into the defect‐induced absorption losses in LISe crystals and promotes the application of LISe crystals in MIR laser generation. [ABSTRACT FROM AUTHOR]

This Letter details a pioneering study on the design and nanofabrication process of a thermoelectric infrared radiation detector using a suspended polyimide membrane. The research includes a comprehensive analysis of thermoelectric doped Bi2Te3 thin films, comparing their expected performance regarding noise and specific detectivity with other infrared detectors, particularly those in the silicon sector. Experimental results and calculations shed light on responsivity and time constants. In the absence of absorption layers, specific detectivity values for visible and near infrared radiation are measured at 9.2 × 107 and 2.9 × 107 cm Hz / W , respectively, with a time constant nearing 20 ms. Calculations show that introducing an optimized absorption layer with ε = 1 significantly improves specific detectivity, reaching 9.0 × 108 cm Hz / W. Subsequent calculations also show that further enhancement can be obtained by etching the polyimide membrane to a 1-micron thickness, resulting in an exceptional specific detectivity value of 8.4 × 109 cm Hz / W , placing it among the best in the current state-of-the-art. [ABSTRACT FROM AUTHOR]

This study aims to determine the percentage of chicken meat in beef and chicken mixtures, which is the most common form of beef adulteration. Ground beef and beef sausages were prepared with mixtures containing chicken meat, ranging from 0.0% to 100.0% with 5.0% increments, and analyzed using a near-infrared spectroscopy device. Optimal analysis conditions were determined through the examination of a wide range of regression models. The best regression model for ground beef mixtures yielded the following results: RMSEC (Root Mean Square Error of Calibration): 2.35, RMSEV (Root Mean Square Error of Validation): 3.36, R²C (R-Value Calibration): 0.99, R2V (R-Value Validation): 0.98. The results for beef sausages were as follows: RMSEC: 2.56, RMSEV: 3.66, R²C: 0.99, R2V: 0.98. As a result, the chicken meat content in beef mixtures was detected with a margin of error of 2.05%, while the chicken meat content in beef sausages was detected with a margin of error of 2.12%. [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]

High quantum efficiency (QE) X-ray absorbers are needed for future X-ray astrophysics telescopes. The Advanced Telescope for High ENergy Astrophysics (ATHENA) mission requirements for the X-ray Integral Field Unit (X-IFU) instrument dictate, at their most stringent, that the absorber achieve vertical QE > 90.6% at 7 keV and low total heat capacity, 0.731 pJ/K. The absorber we have designed is 313 µm square composed of 1.05 μm Au and 5.51 μm electroplated Bi films (Barret et al. in Exp Astron 55:373–426, 2023). Overhanging the TES, the absorber is mechanically supported by 6 small legs whose 5 μm diameter is tuned to the target thermal conductance for the device. Further requirements for the absorber for X-IFU include a > 40% reflectance at wavelengths from 1 to 20 μm to reduce shot noise from infrared radiation from higher temperature stages in the cryostat. We meet this requirement by capping our absorbers with an evaporated Ti/Au thin film. Additionally, narrow gaps between absorbers are required for high fill fraction, as well as low levels of fine particulate remaining on the substrate and zero shorts between absorbers that may cause thermal crosstalk. The Light Element Mapper (LEM) is an X-ray probe concept optimized to explore the soft X-ray emission from 0.2 to 2.0 keV. These pixels for LEM require high residual resistance ratio (RRR) thin 0.5 µm Au absorbers to thermalize uniformly and narrow < 2 μm gaps between pixels for high areal fill fraction. This paper reports upon technology developments required to successfully yield arrays of pixels for both mission concepts and presents first testing results of devices with these new absorber recipes. [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]

The inefficiency of ethanol oxidation reaction (EOR) presents a significant obstacle in harnessing renewable biofuels with high energy density into electricity. Despite efforts, most Pt-based catalysts still suffer from drawbacks such as poor activity and susceptibility to CO poisoning, particularly in acidic conditions. Herein, we employed a physical laser-assisted approach to synthetize a PtPd alloy with a 1:1 atomic ratio. This alloy demonstrates remarkable performance in acidic EOR, boasting a high mass activity of 1.86 A·mgPt−1 and competitive resistance to poisoning. Combining in situ synchrotron radiation infrared spectroscopy with theoretical calculations, we reveal that the synergic interaction between Pt and Pd enhances both the adsorption of OH* intermediate and the dehydrogenation ability of ethanol. This work will prove the feasibility of synthesizing bimetallic alloys by a physical laser-assisted strategy and promote the development of advanced alloy electrocatalysts. [ABSTRACT FROM AUTHOR]

Researching and manufacturing materials that possess both electromagnetic interference (EMI) shielding and infrared stealth capabilities is of great significance. Herein, an ultrathin polyimide-based nonwoven fabric with low-reflection EMI shielding/infrared stealth performance is successfully fabricated by in-situ loading of Fe3O4/Ag nanoparticles on the surface of polyimide (PI) fiber (PFA), and followed by bonding with a commercial Cu/Ni mesh. The synergistic assembly of PFA and Cu/Ni promotes the rational construction of hierarchical impedance matching, inducing electromagnetic waves (EMW) to enter the composite and be dissipated as much as possible. Meanwhile, the existence of Cu/Ni mesh on back of PFA facilitates the formation of electromagnetic resonance and destructive interference of EMW reflected from composite, leading to a lower-reflectivity (0.26) EMI shielding performance of 58 dB within 24–40 GHz at a thinner thickness (430 µm). More importantly, the fluffy PFA nonwoven fabric and metal Cu/Ni mesh endow composite with good thermal insulation and low infrared emissivity, resulting in excellent infrared stealth performance in various environments. As a result, such excellent compatibility makes it possible to become a promising defense material to be applied in military tent for preventing electromagnetic and infrared radiation. [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]

Si is opaque to visible light, but transparent to infrared rays. Therefore, when the infrared laser is focused inside Si, the focal portion becomes ultra-hot, forming a modified volume (Laser induced modified volume: LIMV) inside. After the laser beam is injected into the Si wafer at equal intervals (for example, 5 µm) in the cross direction, and then a force is applied from the outside. Then, cracks are formed from LIMV, and the Si wafer is divided into small pieces of 5 µm square. This is the stealth dicing (SD) technology, which is now widely used in the manufacture of semiconductor devices. In this process, clarifying the nature of LIMV is of great industrial and academic significance. The authors have been engaged in elucidating the mechanism of LIMV development by TEM observation. This phenomenon, which at first seemed extremely puzzling, was finally elucidated. In this overview, we would like to describe the process that led to this elucidation in chronological order. This phenomenon is extremely puzzling, and due to the author’s lack of knowledge, there were errors in the contents of the papers published so far, so we have corrected them in this overview. [ABSTRACT FROM AUTHOR]

This study investigates the co‐combustion of palm oil biodiesel fuel, as a renewable alternative for diesel fuel, inside natural gas flame to enhance the flame thermal specifications and NOx reduction. A power natural gas burner with a maximum heat capacity of 418,400 kJ/h was installed at the inlet of a laboratory furnace and biodiesel fuel was injected inside natural gas burner with a 100 μm in diameter solid cone nozzle. Flame temperature, thermal radiation, Infrared radiation, and CO, CO2 and NOx emission were measured. The results revealed that biodiesel injection increases the flame size and turns the non‐luminous blue flame into yellow‐colored flame. Furthermore, higher flash point and Sauter Mean Diameter of biodiesel promote the thermal decomposition of fuel droplets and increase the concentrations of Intermediate Soot Particles in the flame which in turn increases the flame emissivity coefficient and consequently flame thermal radiation. Also, the oxygen content of biodiesel fuel has an important role in the complete combustion of Intermediate Soot Particles to CO2 which increases the heat release of biodiesel combustion and raises the flame temperature. The average enhancement in thermal radiation and flame temperature were 5.6% and 43.38%, respectively. Finally, although biodiesel injection increases the flame temperature, it also increases the flame surface reaction and eliminates the hot spot region in the flame. Therefore, the rate of heat generation per unit volume of flame decreases and this decreases the rate of NOx emission as much as 10.84%. [ABSTRACT FROM AUTHOR]

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.

Selective infrared radiation is crucial for achieving infrared stealth and heat dissipation. Artificially designed superstructure film (SF) provides several advantages for controlling and modulating infrared radiation, making them a promising solution for these applications. The research described in this work has successfully produced broadband selective infrared radiation by using a surface made up of circular patches that are combined. Numerical simulations show that this SF can achieve broadband selective radiation with 3–5 μm mid-wave infrared (MWIR) suppression and 8–14 μm long-wave infrared (LWIR) emission. The spectral selectivity can be easily switched to high emissivity in MWIR and low emissivity in LWIR by simply changing the basal layer. The resonance mechanism for achieving broadband spectral selectivity in the SF may be due to a combination of multimode plasmon resonances that are induced by the structural nonrotational symmetry of the circular patches. By applying the selective radiation SF on the tail nozzle or the vehicle, the effect of thermal management is very significant. Selective radiation SF can reduce radiant energy in the 3−5 μm band by a significant amount at 500 °C, resulting in a 46 °C cooler temperature than that at the body without the SF. At 80 °C, radiated energy in the 8–14 μm band is also considerably reduced and the temperature is 10 °C lower than that of the body without the SF. There will be obvious advantages in potential applications for infrared stealth and heat dissipation by the designed SF, a simple and convenient manufacturing process. [ABSTRACT FROM AUTHOR]