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Intestinal absorption of compounds is significant in drug research and development. To evaluate this efficiently, a method combining mathematical modeling and molecular simulation was proposed, from the perspective of molecular structure. Based on the quantitative structure-property relationship study, the model between molecular structure and their apparent permeability coefficients was successfully constructed and verified, predicting intestinal absorption of drugs and interpreting decisive structural factors, such as AlogP98, Hydrogen bond donor and Ellipsoidal volume. The molecules with strong lipophilicity, less hydrogen bond donors and receptors, and small molecular volume are more easily absorbed. Then, the molecular dynamics simulation and molecular docking were utilized to study the mechanism of differences in intestinal absorption of drugs and investigate the role of molecular structure. Results indicated that molecules with strong lipophilicity and small volume interacted with the membrane at a lower energy and were easier to penetrate the membrane. Likewise, they had weaker interaction with P-glycoprotein and were easier to escape from it and harder to export from the body. More in, less out, is the main reason these molecules absorb well., (© 2024 John Wiley & Sons Ltd.)

Aims: The current work describes the development of mechanistic vaginal absorption and metabolism model within Simcyp Simulator to predict systemic concentrations following vaginal application of ring and gel formulations., Methods: Vaginal and cervix physiology parameters were incorporated in the model development. The study highlights the model assumptions including simulation results comparing systemic concentrations of 5 different compounds, namely, dapivirine, tenofovir, lidocaine, ethinylestradiol and etonogestrel, administered as vaginal ring or gel. Due to lack of data, the vaginal absorption parameters were calculated based on assumptions or optimized. The model uses release rate/in vitro release profiles with formulation characteristics to predict drug mass transfer across vaginal tissue into the systemic circulation., Results: For lidocaine and tenofovir vaginal gel, the predicted to observed AUC 0-t and C max ratios were well within 2-fold error limits. The average fold error (AFE) and absolute AFE indicating bias and precision of predictions range from 0.62 to 1.61. For dapivirine, the pharmacokinetic parameters are under and overpredicted in some studies due to lack of formulation composition details and relevance of release rate used in ring model. The predicted to observed AUC 0-t and C max ratios were well within 2-fold error limits for etonogestrel and ethinylestradiol vaginal ring (AFEs and absolute AFEs from 0.84 to 1.83)., Conclusion: The current study provides first of its kind physiologically based pharmacokinetic framework integrating physiology, population and formulation data to carry out in silico mechanistic vaginal absorption studies, with the potential for virtual bioequivalence assessment in the future., (© 2024 British Pharmacological Society.)

The differentially pumped rare‐gas filter at the end of the VUV beamline of the Swiss Light Source has been adapted to house a windowless absorption cell for gases. Absorption spectra can be recorded from 7 eV to up to 21 eV photon energies routinely, as shown by a new water and nitrous oxide absorption spectrum. By and large, the spectra agree with previously published ones both in terms of resonance energies and absorption cross sections, but that of N2O exhibits a small shift in the band and tentative fine structures that have not yet been fully described. This setup will facilitate the measurement of absorption spectra in the VUV above the absorption edge of LiF and MgF2 windows. It will also allow us to carry out condensed‐phase measurements on thin liquid sheets and solid films. Further development options are discussed, including the recording of temperature‐dependent absorption spectra, a stationary gas cell for calibration measurements, and the improvement of the photon energy resolution. [ABSTRACT FROM AUTHOR]

In order to effectively comprehend the impact of alloying element equilibrium relationship of binary nano‐magnetic particles on their electromagnetic wave absorption performance, four sets of binary nano FeNi magnetic particles with Fe:Ni alloy ratios of 2:8, 4:6, 6:4, and 8:2 were prepared with liquid‐phase reduction and the microstructure, static magnetic properties, and electromagnetic wave absorption performance of the particles were studied. The results show that the nano FeNi magnetic particles exhibit a spherical geometric structure, with a decrease in crystallinity as the Fe:Ni alloy ratio increases. The remanence and coercivity initially increase and then decrease with the increased Fe:Ni alloy ratio, with a 270 % decrease in saturation magnetization intensity as the alloy ratio changes from 2:8 to 8:2. With the increase in the Fe:Ni alloy ratio, the real and imaginary parts of the complex permittivity exhibit a decreasing trend, while the real part of the magnetic permeability decreases with increasing frequency. Aside from the 8:2 Fe:Ni alloy ratio, significant polarization relaxation losses were observed in the prepared magnetic particles, with eddy current losses was not the main mechanism of magnetic losses. The attenuation constant shows a peak at high frequencies, and the impedance matching performance increases with the increase in the Fe:Ni alloy ratio. When the Fe:Ni alloy ratio changes from 2:8 to 8:2, the minimum reflection loss decreased by 3340 %, and at a thickness of 2.1 mm and a frequency of 12 GHz, the FeNi alloy particles with a ratio of 2:8 exhibited a minimum reflection loss of −17.2 dB with an effective absorption bandwidth of 1.92 GHz. [ABSTRACT FROM AUTHOR]

The aim of achieving integration of lightweight, high strength, high‐temperature resistant, and satisfactory electromagnetic (EM) wave absorption was successfully accomplished in the present study by synthesizing TiC–TiB2 fibers reinforced Si3N4 composites, which were pressureless sintered at 1650°C for 2 h. The preparation of TiC–TiB2 fibers was conducted through a chloride‐assisted carbothermic method. This work focused on investigating the effects of incorporating TiC–TiB2 fibers on the mechanical properties and EM wave absorption characteristics of the composites. The 30 wt% TiC–TiB2/Si3N4 composite displayed the bulk density of 1.89 g/cm3, bending strength of 93.11 ± 3.91 MPa, fracture toughness of 1.81 ± 0.10 MPa m1/2, minimum reflection loss of −38.87 dB, and effective absorption bandwidth of 1.43 GHz in the Ku‐band, respectively. The as‐synthesized TiC–TiB2/Si3N4 composites are promising candidates for EM wave absorbing load‐bearing materials due to their outstanding mechanical properties and microwave absorption properties. [ABSTRACT FROM AUTHOR]

MoAlB powders with a purity of 96 wt.% were successfully fabricated by a laser‐induced self‐propagating method using molybdenum boride (MoB) and aluminum powders as starting materials under the conditions of an n(MoB): n(Al) ratio of 1.0:1.4 and the laser linear energy density (El) of 0.9 J/mm, and the effect of raw material composition and El on the phase composition and microstructure of the resultant MoAlB powders were investigated. The minimum reflection loss (RLmin) value and effective absorption bandwidth (EAB) of the as‐prepared MoAlB absorber with a thickness of 5.0 mm were only determined as −12.5 dB (at 16.9 GHz) and 0.9 GHz (16.4–17.3 GHz) in the frequency of 1–18 GHz, respectively. Nevertheless, the RLmin and EAB of as‐prepared MoAlB powders oxidized after 3 h at 773 K increased to −18.59 dB (at 15.82 GHz) and 2.13 GHz (15.22–17.35 GHz), respectively, demonstrating that the as‐prepared MoAlB powders are potential candidates for high‐temperature microwave absorption applications. This study proposes a new efficient strategy for the preparation of boron‐based ternary compounds for high‐temperature electromagnetic wave absorption application. [ABSTRACT FROM AUTHOR]

This article discusses a school experiment on carbon dioxide (CO2) absorption as an example of gas absorption experiments in the classroom. The experiment aims to illustrate the process of CO2 absorption and consider relevant factors such as temperature and concentration. Students can use a newly developed measuring system to independently carry out and quantify the absorption process. The experiment highlights the interdisciplinary work between the subjects of Science and Technology and Chemistry. The text describes an experiment on CO2 absorption using a sensor box and Arduino measurement device. The experiment involves connecting the components, setting the parameters, and measuring the CO2 concentration. The results can be displayed on an OLED display and recorded on an SD card. The experiment explores the absorption process using different parameters such as absorption medium, concentration, temperature, and amount of absorbent. The experiment is flexible and can be used for industrial CO2 purification or atmospheric CO2 reduction. The text also highlights the importance of sensor technology in visualizing invisible natural processes. The experiment is designed to be user-friendly and suitable for educational settings. [Extracted from the article]

We study the Helmholtz equation with periodic coefficients in a closed waveguide. A functional analytic approach is used to formulate and solve the radiation problem in a self‐contained exposition. In this context, we simplify the non‐degeneracy assumption on the frequency. Limiting absorption principles (LAPs) are studied, and the radiation condition corresponding to the chosen LAP is derived; we include an example to show different LAPs lead, in general, to different solutions of the radiation problem. Finally, we characterize the set of all bounded solutions to the homogeneous problem. [ABSTRACT FROM AUTHOR]

Local structure of β‐(AlxGa1−x)2O3 alloys with Al contents is determined from extended X‐ray absorption fine structure spectroscopy (EXAFS). A model to fit the EXAFS data for monoclinic β‐(AlxGa1−x)2O3 is suggested to independently determine local structure parameters. An increase in compositional disorder corresponding to the near neighbors (NNs) for lower Al contents establishes that the Al atom does occupy tetrahedron sites in addition octahedron sites even for smaller Al contents. NNs and next‐nearest neighbor (NNN) bond lengths corresponding to tetrahedron and octahedron coordinated gallium (Ga) atoms with surrounding oxygen (O) atoms as well as tetrahedron–tetrahedron/octahedron–octahedron coordinated GaGa atoms on average decrease with Al content up to x = 33.3% and then they saturates with further increase in Al content. However, tetrahedron–octahedron coordinated GaGa atoms move far apart with Al content up to x = 33.3% and then it saturates. The physical picture indicates the creation of tetrahedra and octahedra sublattices locally for β‐(AlxGa1−x)2O3, and their sizes decrease, but they move far apart up to a certain Al content. Thereafter, both saturate. Thus, EXAFS provide a clear insight into the evolution of local structure of β‐(AlxGa1−x)2O3 with Al content, which is useful for better understanding of their physical properties. [ABSTRACT FROM AUTHOR]

The current work is interested on investigating the impacts of thermal radiation, chemical reaction, and absorption radiation of a hydromagnetic convection‐free mass and heat transfer flow in case of an electrically conducting fluid that passes through a vertical plate moving impulsively. The analytical solutions of the governing momentum, energy, and species concentration equations with the initial and boundary conditions are obtained by the Laplace transformation technique. Graphs for fluid characteristics are used to analyze the impact of changing parametric quantities such as M, N, Sc, Kc, Q, Gr, Gm, and t on the temperature, velocity, concentration, and Sherwood number. We derive the engineering curiosity expressions for the Nusselt number and stress, and at the end, we tabulate and discuss the consequences of new parameters. The magnetic field effect and the chemical reaction are seen to diminish the fluid velocity and concentration, respectively, but in contrast, the absorption radiation effect is seen to accelerate both velocity and temperature. It is closely studied that the Nusselt number and skin friction values for hydrogen consistently exceed those for carbon monoxide. [ABSTRACT FROM AUTHOR]

In this work, an investigation has been carried out on the sound absorption properties of the microperforated composites prepared by filling natural luffa fiber and synthetic luffa fiber. These composite structures are created by 3‐dimensional printing of polylactic acid, which exhibits excellent biodegradability. After preparing the structure, the micro‐perforation is done at the top of the composite with the help of a heated cylindrical drill. During the printing process, the infill density (printing parameter) and type of luffa fiber (natural and synthetic) have been varied to find out its effect on acoustic properties. Finally, a comparative study is carried out among natural luffa fiber and without using natural luffa fiber. The results showed excellent sound absorption of luffa filled structure compared to an unfilled structure. Out of three different infilled densities, the density of 5 % revealed a maximum amount of absorption, suggesting the potential applications of these structures in the field of sound absorption. [ABSTRACT FROM AUTHOR]

Modern society's keen regard for aesthetics made hair products an integral part of a multi‐billion‐dollar cosmetic industry. Hair care products (e.g., shampoos and conditioners) and chemical treatments (e.g., bleaching and permanent waving) result in various effects on the morphological attributes of hair. Generally, water adsorbed on the hair surface is known to significantly dictate the hair's mechanical characteristics (smoothness and friction), and hair's macroscopic wettability has been commonly used to indicate its surface properties. However, an approach to selectively characterize the hydration water in the hair surface is required to accurately understand the intermolecular events between the hair and its vicinal water. In this paper, we successfully obtained the infrared (IR) absorption spectra of the hydration water of human hair. We employed the multivariate curve resolution‐alternating least square (MCR‐ALS) method to separate the hydration and bulk water spectra from the whole spectra. Comparing the IR spectra of the hydration water of chemically untreated and bleached hair samples, we conclude that water molecules form strong hydrogen bonds with the bleached hair surface due to the destruction of the hair's hydrophobic outer layer and the consequent formation of hydrophilic residues. [ABSTRACT FROM AUTHOR]

Accurate analysis of the rich information contained within X‐ray spectra usually calls for detailed electronic structure theory simulations. However, density functional theory (DFT), time‐dependent DFT and many‐body perturbation theory calculations increasingly require the use of advanced codes running on high‐performance computing (HPC) facilities. Consequently, many researchers who would like to augment their experimental work with such simulations are hampered by the compounding of nontrivial knowledge requirements, specialist training and significant time investment. To this end, we present Web‐CONEXS, an intuitive graphical web application for democratizing electronic structure theory simulations. Web‐CONEXS generates and submits simulation workflows for theoretical X‐ray absorption and X‐ray emission spectroscopy to a remote computing cluster. In the present form, Web‐CONEXS interfaces with three software packages: ORCA, FDMNES and Quantum ESPRESSO, and an extensive materials database courtesy of the Materials Project API. These software packages have been selected to model diverse materials and properties. Web‐CONEXS has been conceived with the novice user in mind; job submission is limited to a subset of simulation parameters. This ensures that much of the simulation complexity is lifted and preliminary theoretical results are generated faster. Web‐CONEXS can be leveraged to support beam time proposals and serve as a platform for preliminary analysis of experimental data. [ABSTRACT FROM AUTHOR]

As a rapidly expanding family of 2D materials, MXenes have recently gained considerable attention. Herein, by developing a coating method that enables transfer‐free and layer‐by‐layer film coating, the nonlinear optical absorption (NOA) of Ti3C2Tx MXene films is investigated. Using the Z‐scan technique, the NOA of the MXene films is characterized at ≈800 nm. The results show that there is a strong and layer‐dependent NOA behavior, transitioning from reverse saturable absorption (RSA) to saturable absorption (SA) as the layer number increases from 5 to 30. Notably, the nonlinear absorption coefficient β changes significantly from ≈7.13 × 102 cm GW−1 to ≈−2.69 × 102 cm GW−1 within this range. The power‐dependent NOA of the MXene films is also characterized, and a decreasing trend in β is observed for increasing laser intensity. Finally, the NOA of 2D MXene films at ≈1550 nm is characterized by integrating them onto silicon nitride waveguides, where an SA behavior is observed for the films including 5 and 10 layers of MXene, in contrast to the RSA observed at ≈800 nm. These results reveal intriguing nonlinear optical properties of 2D MXene films, highlighting their versatility and potential for implementing high‐performance nonlinear photonic devices. [ABSTRACT FROM AUTHOR]

Excellent electromagnetic wave loss and impedance matching are typical characteristics of superior‐performance electromagnetic wave (EMW) absorption materials. Changing the component ratios and multidimensional combinations of various absorbing materials is one of the best methods to improve absorption performance. This work used a convenient physical mixing approach to combine three wave‐absorbing materials with various dimensions to successfully prepare Graphene/carbon nanotubes/Fe3O4 (G/C/Fe3O4)/paraffin composites. One‐dimensional (1D) tube carbon nanotubes (CNTs) pierced two‐dimensional (2D) sheet graphene to form a strong three‐dimensional (3D) conductive network, enhancing interfacial polarization without introducing zero‐dimensional (0D) magnetic Nano‐Fe3O4. Nevertheless, because of their significant dielectric characteristics, the graphene/carbon nanotube (G/C) paraffin composites displayed low impedance matching and electromagnetic wave absorption properties. At a mass ratio of 1:1, the G/C/paraffin composites achieved an ideal reflection loss (RL) of −11.99 db and an impedance matching value of 0.59. Adding Fe3O4 improved the impedance matching and electromagnetic wave loss performance and promoted the formation of a non‐homogeneous interface, improving interfacial polarization and reflection. The G/C/Fe3O4/paraffin composite, with a mass ratio of 1:1:6 and a filler ratio of 20%, achieved an optimum reflection loss of −37.2 dB and an effective absorption bandwidth of 4.16 GHz. This work optimized and improved the performance of EMW materials practically and rapidly, providing a research method for the widespread application of superior‐performance electromagnetic wave absorption materials. Highlights: The EMW absorption materials with various architectures.1D CNTs pierced 2D sheet graphene to form a strong 3D conductive network.Adding Fe3O4 promoted the formation of a non‐homogeneous interface.Electromagnetic synergies and different structural combinationsIt achieved excellent impedance matching and electromagnetic loss performance. [ABSTRACT FROM AUTHOR]

Lattice structures with customizable acoustical and mechanical properties show significant promise as practical engineering materials. However, the geometry of traditional lattice structures simultaneously dictates both acoustical and mechanical properties, with alterations in one impacting the other, leaving little room for customization. Herein, leveraging the mechanism of Helmholtz resonators, a general recipe is presented to independently introduce sound absorption and mechanical properties in lattice structures. The sound absorption component is based on a perforated plate, while the mechanical component is based on a truss structure. Through a high‐fidelity analytical acoustics model is developed, and finite element analysis outlines the range of properties achievable through the proposed structures. The design encompasses structures with effective absorption, characterized by a resonance peak with coefficient ≥0.7, across almost every frequency in a broad range from 1000 to 5000 Hz, within a range of lattice thicknesses from 21 to 25.5 mm. Also, diverse range of stiffness and strength, and large‐strain deformation modes, can be achieved through the implementation of different trusses. Finally, the concept is validated experimentally through 3D‐printed samples. This innovative approach allows for the tailored creation of lattice structures that specifically address the acoustical and mechanical requirements in diverse applications. [ABSTRACT FROM AUTHOR]

Enniatins are mycotoxins with well‐known antibacterial, antifungal, antihelmintic and antiviral activity, which have recently come to attention as potential mitochondriotoxic anticancer agents. The cytotoxicity of enniatins is traced back to ionophoric properties, in which the cyclodepsipeptidic structure results in enniatin:cation‐complexes of various stoichiometries proposed as membrane‐active species. In this work, we employed a combination of surface‐enhanced infrared absorption (SEIRA) spectroscopy, tethered bilayer lipid membranes (tBLMs) and density functional theory (DFT)‐based computational spectroscopy to monitor the cation‐dependence (Mz+=Na+, K+, Cs+, Li+, Mg2+, Ca2+) on the mechanism of enniatin B (EB) incorporation into membranes and identify the functionally relevant EBn : Mz+ complexes formed. We find that Na+ promotes a cooperative incorporation, modelled via an autocatalytic mechanism and mediated by a distorted 2 : 1‐EB2 : Na+ complex. K+ (and Cs+) leads to a direct but less efficient insertion into membranes due to the adoption of "ideal" EB2 : K+ sandwich complexes. In contrast, the presence of Li+, Mg2+, and Ca2+ causes a (partial) extraction of EB from the membrane via the formation of "belted" 1 : 1‐EB : Mz+ complexes, which screen the cationic charge less efficiently. Our results point to a relevance of the cation dependence for the transport into the malignant cells where the mitochondriotoxic anticancer activity is exerted. [ABSTRACT FROM AUTHOR]

A new method for time‐resolved X‐ray absorption near edge structure (XANES) spectroscopy that enables faster data acquisition and requires smaller sample quantities for high‐quality data, thus allowing the analysis of more samples in a shorter time is introduced. The method uses large bandwidth free electron laser pulses to measure laser‐excited XANES spectra in transmission mode. A beam‐splitting grating configuration allows simultaneous measurements of the spectra of the incoming X‐ray Free Electron Laser (XFEL) pulses and transmission XANES, which is crucial for compensating the pulse‐dependent intensity and spectrum fluctuations due to the self‐amplified spontaneous emission operation. The implementation of this new methodology is applied on a liquid solution of ammonium iron(III) oxalate jet and is compared to previous results, showing great improvements in the speed of acquisition and spectral resolution, and the ability to measure a large 2‐D spectral‐time map quickly. [ABSTRACT FROM AUTHOR]

This work reports a gallium indium alloy (EGaIn)‐doped SiBOC ceramic that possesses a unique liquid‐metal‐in‐ceramic feature. The low‐viscosity liquid nature of gallium‐based liquid metals (Ga‐LMs) and the reactive core‐shell structure provide possibilities for phase engineering inside polymer‐derived ceramics. As a demonstration, EGaIn nanoparticles (NPs) are directly mixed with a UV‐curable ceramic precursor (UV‐PBS) to obtain a resin suitable for digital light processing 3D‐printing. After pyrolysis at 800–1200 °C, SiBOC ceramics with uniformly distributed EGaIn NP domains (Si(GaIn)BOC) are obtained. EGaIn plays a key role in promoting carbonization and preventing crack formation during the polymer‐to‐ceramic process, resulting in an increase in both ceramic yield and mechanical strength. EGaIn NPs are also found to have a core‐shell structure (EGaIn@(GaxIn1‐x)2O3@SiBOC) inside the SiBOC matrix, which significantly enhances the dielectric properties and improves the interfacial polarization. As a result, an excellent electromagnetic wave absorption performance is achieved across the C, X, and Ku bands, respectively. Through rational design, a novel metastructure design based on the Schwarz P minimal surface is proposed, which exhibits an ultrawide effective absorption band extending up to 11.36 GHz (within C‐Ku bands). [ABSTRACT FROM AUTHOR]

Processing of single‐crystal X‐ray diffraction data from area detectors can be separated into two steps. First, raw intensities are obtained by integration of the diffraction images, and then data correction and reduction are performed to determine structure‐factor amplitudes and their uncertainties. The second step considers the diffraction geometry, sample illumination, decay, absorption and other effects. While absorption is only a minor effect in standard macromolecular crystallography (MX), it can become the largest source of uncertainty for experiments performed at long wavelengths. Current software packages for MX typically employ empirical models to correct for the effects of absorption, with the corrections determined through the procedure of minimizing the differences in intensities between symmetry‐equivalent reflections; these models are well suited to capturing smoothly varying experimental effects. However, for very long wavelengths, empirical methods become an unreliable approach to model strong absorption effects with high fidelity. This problem is particularly acute when data multiplicity is low. This paper presents an analytical absorption correction strategy (implemented in new software AnACor) based on a volumetric model of the sample derived from X‐ray tomography. Individual path lengths through the different sample materials for all reflections are determined by a ray‐tracing method. Several approaches for absorption corrections (spherical harmonics correction, analytical absorption correction and a combination of the two) are compared for two samples, the membrane protein OmpK36 GD, measured at a wavelength of λ = 3.54 Å, and chlorite dismutase, measured at λ = 4.13 Å. Data set statistics, the peak heights in the anomalous difference Fourier maps and the success of experimental phasing are used to compare the results from the different absorption correction approaches. The strategies using the new analytical absorption correction are shown to be superior to the standard spherical harmonics corrections. While the improvements are modest in the 3.54 Å data, the analytical absorption correction outperforms spherical harmonics in the longer‐wavelength data (λ = 4.13 Å), which is also reflected in the reduced amount of data being required for successful experimental phasing. [ABSTRACT FROM AUTHOR]

As promising candidates for widespread application, advanced ceramic fiber mats with robust mechanical properties are urgently needed. However, the brittleness, fatigue failure, and large density of ceramic fiber pose significant obstacles to its practical application. Herein, a novel SiO2 aerogel/ZrO2 composite nanofibrous membrane (SZCNFM) with excellent flexibility was prepared by introducing SiO2 aerogel nanoparticles into ZrO2 nanofiber via simple co‐electrospinning. The developed tetragonal zirconia phase without changing up to 1200°C endows SZCNFM material with excellent thermal stability. Furthermore, the as‐prepared membranes exhibit fatigue resistance ability which can maintain 98% of the original stress after 100 buckling cycle tests. The addition of mesoporous structure aerogel reduces the heat transfer of the nanofibrous membrane, giving its low thermal conductivity (30 mW/m/K) and low‐frequency sound absorption (noise reduction coefficient of 0.52). Combined with the high‐temperature resistance, low thermal conductivity and excellent sound‐absorption ability make it a promising material for heat insulation and acoustic absorption. [ABSTRACT FROM AUTHOR]

So far, developed microwave absorbers exhibit significant changes in absorption with temperature, which hinder their operation within a wide temperature range. In this paper, a microwave absorber based on SiBCN ceramics was prepared. Due to the excellent high‐temperature stability of SiBCN ceramics, its permittivity changes less with temperature, avoiding the issue of performance deterioration or even failure that traditional refractory absorbers face at high temperatures. The experiment proves the absorption bandwidth for –15 dB of the SiBCN metamaterials absorber (SMA) is 12 GHz at 800°C, with a maximum absorptivity of 99.99%. According to the computed data, the resonance loss contributes 81.9 to 94.5% of the microwave absorption of SMA. This work demonstrates significant potential for applications in radar stealth under harsh conditions. [ABSTRACT FROM AUTHOR]

With the advent of the 5G era, while enjoying the convenience of information in our daily lives, we also face the challenge of dealing with increased and more complex electromagnetic (EM) radiation issues. Therefore, finding EM wave absorbing materials for the operating frequency range (2–18 GHz) of most electronic products has become an important aspect of ensuring human health and environmental safety. In this study, a variety of elements were incorporated into (WZrNbTaM)C powders by calculation and design, where M is Ni, Cr, or Ti. Phase and microstructural analysis demonstrated the successful preparation of a single‐phase solid solution with uniform elements distribution. The magnetic properties of the powders containing Ni and Cr elements exhibited significant improvement. Further analysis revealed that both the impedance matching and EM wave attenuation capabilities of (WZrNbTaCr)C and (WZrNbTaNi)C were enhanced, thereby improving their absorption performance. Compared to (WZrNbTaTi)C, (WZrNbTaCr)C and (WZrNbTaNi)C exhibit a significant improvement in minimum reflection loss (RL), with an increase of 27.1% and 37.2%, reaching −45.21 and −48.79 dB, respectively. The maximum effective absorption bandwidth (EAB) has also increased by 22.9% and 48.6%, reaching 3.44 and 4.16 GHz, respectively. It is noteworthy that (WZrNbTaCr)C and (WZrNbTaNi)C achieved these excellent absorption properties while maintaining a matching thickness of 1.07 and 1.17 mm. This lightweight and thin performance meets the requirements for use in special scenarios while ensuring the outstanding absorption performance. [ABSTRACT FROM AUTHOR]

Combining photodynamic antimicrobials with nonwovens is prospective. However, common photosensitizers still have drawbacks such as poor photoactivity and the inability to charge. In this study, a photodynamic and high‐efficiency antimicrobial protective material was prepared by grafting bis benzophenone‐structured 4,4‐terephthaloyl diphthalic anhydride (TDPA) photosensitizer, and antimicrobial agent chlorogenic acid (CA) onto spunbond‐meltblown‐spunbond (SMS) membranes. The charging rates for ·OH and H2O2 were 6377.89 and 913.52 μg/g/h. The light absorption transients structural storage remained above 69% for 1 month. High electrical capacity remained after seven cycles indicating its rechargeability and recyclability. The SMS/TDPA/CA membrane has excellent bactericidal performance when under illumination or lightless conditions, and the bactericidal efficiency of Escherichia coli and Staphylococcus aureus reached over 99%. The construction of self‐disinfection textiles based on the photodynamic strategies proposed in this paper is constructive for expanding and promoting the application of textile materials in the medical field. [ABSTRACT FROM AUTHOR]

Brown carbon (BrC) in China is of great interest to the regional and global climate due to its strong absorption of sunlight. However, the contribution of BrC to total carbonaceous aerosol light absorption and its direct radiative effects (DRE) in China remains largely uncertain. To better assess its climate impact in China, we develop an explicit BrC scheme and implement it in a global climate model, which includes optical parameters of primary BrC derived from local measurements, secondary BrC absorption, and a photobleaching parameterization of BrC. By comparing with multi‐type observational data, we find that with the implementation of this scheme, the model captures the seasonal variations of BrC light absorption well in China. The model estimates that BrC contributes 19% and 12% to the total light absorption of carbonaceous aerosol in China in winter and summer, resulting in 0.110 and 0.205 W m−2 of DRE, respectively. Plain Language Summary: While the existing research on the direct radiative effects (DRE) of brown carbon (BrC) predominantly focuses on biomass‐burning sources, little attention has been given to BrC originating from anthropogenic sources. Coal combustion and residential fuels used for cooking and heating release many brown carbon aerosols in China. Source of BrC in China is different from that in Europe and North America. Therefore, studying the light‐absorbing properties and climate effects of BrC in China is of great scientific significance. Here, we introduce local optical parameters of primary BrC based on observations in China, secondary BrC absorption, and chemical bleaching of BrC in a global climate model (GCM). We find that the model can simulate the strong seasonal variations of BrC absorption observed in China. With the help of the model and multi‐type measurement data, we estimate the contribution of BrC to the total carbonaceous aerosol absorption and the DRE of BrC in China in different seasons. This study is the first attempt to introduce an explicit BrC scheme in a GCM to estimate the DRE of BrC in China. Key Points: An explicit brown carbon (BrC) scheme is introduced in a climate model together with observations to constrain light absorption of BrCBrC contributes 19% and 12% of total carbonaceous aerosol absorption in China in winter and summer, respectivelySimulated direct radiative effects due to BrC absorption over China are 0.110 and 0.205 W m2 in the winter and summer seasons [ABSTRACT FROM AUTHOR]

The pivotal role of Brownian and thermophoresis in investigating the flow characteristic of polar nanofluid is important nowadays due to various engineering applications. The enhanced thermal and transport properties in the field of biomedical nanomedicine for hyperthermia treatments, and for enhancing the efficiency of heat exchange processes in cooling electronic devices, heat exchangers, and automotive engines the use of Brownian and thermophoresis is important. Therefore, the present study reveals the importance of Darcy–Forchheimer inertial drag combined with the space‐ and temperature‐dependent heat generation/absorption on the flow of polar nanofluid over an elongating surface. The surface is considered to be permeable for which the hydromagnetic flow in the presence of thermal radiation specifically, Brownian and thermophoresis affects the flow phenomena significantly. The proposed flow model designed with the aforementioned physical properties is standardized into the set of nonlinear ordinary equations by the implementation of suitable similarity rules. Further, the characteristics of various physical quantities are deployed by solving the system by using traditional Rung–Kutta fourth‐order technique. Further, the analysis of several factors is deployed briefly via graphically, and simulation of rate coefficients is presented through tables. The important outcomes of the study are deployed as the inclusion of thermal and solutal buoyancy enhances the velocity distribution, whereas reverse impact is observed for the increasing inertial drag. Also, space‐ and temperature‐dependent heat source augments the temperature profile but Lewis number decelerates the fluid concentration significantly. [ABSTRACT FROM AUTHOR]

To address challenges such as signal interference and crosstalk, the development of novel materials with the ability of electromagnetic absorption (EMA) is imperative. In this study, the composition of the B‐site of CsPbBr3 was fixed for all samples Pb0.2Fe0.2Co0.2Ni0.2Mn0.2 with varying A/B ratios of 1:1, 1:2, and 1:3. We achieved good EMA properties for the Cs1(Pb0.2Fe0.2Co0.2Ni0.2Mn0.2)3O3, including a minimum reflection loss of 75 dB at 10.2 GHz and a 2.5 mm thickness, accompanied by an exceptionally wide effective bandwidth of 8.8 GHz. X‐ray diffraction, transmittance electron microscopy, and X‐ray photoelectron spectroscopy, etc. were used to characterize the structure, morphology, and EMA‐associated properties of CsMBr3. The presence of high entropy was validated through meticulous analysis using Rietveld and grazing‐incidence wide‐angle scattering patterns. The magnetic permeability, dielectric constant, polarization, and attenuation loss were improved with a high‐entropy ratio of 3 within the 30–50 nm crystals. Notable lattice distortion within PbBr6 and phase transition within high‐entropy alloying are the driving forces behind these enhanced EMA characteristics. [ABSTRACT FROM AUTHOR]

The infrared spectral characteristics of organic‐rich acid residues prepared from Ryugu samples returned by the JAXA Hayabusa2 mission generally match those from unheated carbonaceous chondrite meteorites, but the residues from Ryugu are richer in methyl and methylene functional groups and have higher CH2/CH3 ratios. Moreover, two distinct outlier carbonaceous phases are found; one with spectral characteristics of N‐H functional groups, likely amides, and a second phase containing less nitrogen. Such infrared characteristics of Ryugu organic matter might indicate the pristine nature of the freshly collected samples and reflect the near‐surface chemistry in the parent asteroid. [ABSTRACT FROM AUTHOR]

This study introduces a novel iterative Bragg peak removal with automatic intensity correction (IBR-AIC) methodology for X-ray absorption spectroscopy (XAS), specifically addressing the challenge of Bragg peak interference in the analysis of crystalline materials. The approach integrates experimental adjustments and sophisticated post-processing, including an iterative algorithm for robust calculation of the scaling factor of the absorption coefficients and efficient elimination of the Bragg peaks, a common obstacle in accurately interpreting XAS data, particularly in crystalline samples. The method was thoroughly evaluated on dilute catalysts and thin films, with fluorescence mode and large-angle rotation. The results underscore the technique's effectiveness, adaptability and substantial potential in improving the precision of XAS data analysis. While demonstrating significant promise, the method does have limitations related to signal-to-noise ratio sensitivity and the necessity for meticulous angle selection during experimentation. Overall, IBR-AIC represents a significant advancement in XAS, offering a pragmatic solution to Bragg peak contamination challenges, thereby expanding the applications of XAS in understanding complex materials under diverse experimental conditions. [ABSTRACT FROM AUTHOR]

The graphite/Al2O3 composite was prepared using plasma spray technology, the material design, experimental methods, and process flow are introduced. The microstructure, chemical composition, and complex permittivity of the composite are investigated, and its performance to absorb electromagnetic waves is studied. The mechanism of interaction between chemical composition, microstructure, complex permittivity, and absorption performance is analyzed. Furthermore, a microwave absorber composed of graphite/Al2O3 and sheet resistance, and performance is discussed. The reflectivity of the composite coating with different periods and sizes and resistances is analyzed. The impedance and reflectivity of the designed absorber that contains sheet resistance are discussed, and its absorption mechanism is explained in detail. The results demonstrate that the microwave absorption performance of graphite/Al2O3 coating is enhanced by electromagnetic resonance of the sheet resistance. The designed absorber exhibits good wave‐absorbing performance and stability at the frequency of the 8.2–18 GHz range. When the sample thickness is 2.3 mm, the absorber achieves a reflection loss (RL) value of −16.8 dB at 9.8 GHz and a wide effective absorption bandwidth (EAB) of 9.8 GHz. It means that the RL below −10 dB can be obtained in the whole X band and Ku bands. These results proved that the EAB can be tuned and enhanced by manipulating sheet resistance. [ABSTRACT FROM AUTHOR]

Highlights Designing an electromagnetic wave absorber that can meet the needs of wide frequency, high efficiency, wide‐angle absorption and strong mechanical bearing capacity is still a challenge. In this paper, a core‐shell structure Carbonyl iron powder (CIP)@Carbon (C)@Carbon black (CB) composite material was prepared by coating and vacuum carbonization process. Using it as a filler, PLA as a matrix to prepare 3D printing composites. The unique structure and material distribution of CIP@C@CB gives the composite a variety of loss mechanisms that greatly improve microwave absorption capacity. Superstructure electromagnetic wave absorbers with integrating broadband microwave absorption and good mechanical bearing performance were designed and prepared by using CIP@C@CB/PLA 3D printing composites. By optimizing the parameters of this superstructure absorber, an EAB of 5.5–18 GHz is realized, and its yield limit reaches 11.5 MPa. In addition, the superstructure absorber also has excellent wide‐angle absorption capacity, with an effective absorption bandwidth (EAB) of 10GHz at 0°–40° transverse radio (TE) and 0–70° transverse magnetic wave (TM). This research offers a straightforward and effective method for crafting broadband wide‐angle absorbers that possess the added advantage of mechanical load‐bearing capacity. The core‐shell structure was prepared by coating and carbonization processes. The unique structure of CIP@C@CB enhances the interfacial polarization effect. At a thickness of 2 mm, 30% CIP@C@CB/PLA achieves a maximum EAB of 5.0 GHz. The stepped structure achieves 90% effective absorption in the 5.5–18 GHz range. [ABSTRACT FROM AUTHOR]

Nano‐heterointerface engineering has been demonstrated to influence interfacial polarization by expanding the interface surface area and constructing a built‐in electric field (BEF), thus regulating electromagnetic (EM) wave absorption. However, the dielectric‐responsive mechanism of the BEF needs further exploration to enhance the comprehensive understanding of interfacial polarization, particularly in terms of quantifying and optimizing the BEF strength. Herein, a “1D expanded 2D structure” carbon matrix is designed, and semiconductor ZnIn2S4 (ZIS) is introduced to construct a carbon/ZIS heterostructure. The cross‐dimensional nano‐heterointerface design increases interface coupling sites by expanding the interface surface area and induces an increase in the Fermi level difference on both sides of the interface to modulate the distribution of interface charges, thereby strengthening the BEF at the interface. The synergistic effect leads to excellent EM absorption performance (minimum reflection coefficient RCmin = −67.4 dB, effective absorption bandwidth EAB = 6.0 GHz) of carbon/ZIS heterostructure. This work introduces a general modification model for enhancing interfacial polarization and inspires the development of new strategies for EM functional materials with unique electronic behaviors through heterointerface engineering. [ABSTRACT FROM AUTHOR]

The pursuit of eco‐friendly electromagnetic wave absorption (EMWA) materials with multifunctional capabilities has garnered significant attention in practical applications. However, achieving these desired qualities simultaneously poses a significant challenge. This study introduces a single‐step calcination and chemical polymerization process to obtain an environmentally friendly ant‐nest‐inspired hybrid composite by optimizing conductive polypyrrole nanotubes (PNTs) within a 3D carbonaceous structure. The biomimetic composite forms a highly efficient conductive network, providing a pathway for free electrons within the carbonaceous barriers and enhancing the conduction loss. Remarkably, the EMWA performance of the composite achieves ultrathin (1.6 mm), wide effective absorption band (5.4 GHz), and strong absorption intensity (−67.6 dB) features. Moreover, due to the complex and intertwined 3D continuous network, the obtained samples exhibit excellent thermal insulation and superhydrophobic behavior by inhibiting heat transfer and preventing localized areas from being prone to water absorption. These findings not only offer a sustainable and low‐cost production route for biomimetic carbonaceous composites but also demonstrate a high‐efficiency absorber with great multifunctionality as a green alternative to traditional EMWA materials. [ABSTRACT FROM AUTHOR]

The preparation of core–shell structured nanoparticles using the galvanic replacement reaction of liquid metals is a simple and efficient method. However, precise modulation of the core and shell components to regulate the microwave absorption performance still needs to be further explored. In this study, various types of indium/oxide core–shell nanoparticles are prepared based on a competitive galvanic reaction of gallium‐indium liquid metals. The prepared indium/oxide core–shell structured nanoparticles exhibit superior electromagnetic (EM) wave absorption properties with a minimum reflection loss (RL) of −40.25 dB at 1.7 mm and the widest effective absorption band of 6.12 GHz at 2.1 mm. The superior wave‐absorbing properties originate from the dielectric losses of the interfacial and dipole polarizations. In addition, an externally applied magnetic field improves the polarization loss and microwave dissipation to achieve a minimum RL of −45.65 dB at 2.4 mm. The liquid‐metal‐assisted competitive galvanic reaction strategies extend the variety of core–shell structured nanoparticles for electromagnetic wave absorption applications. [ABSTRACT FROM AUTHOR]

This study utilizes the strong complexation effect of polydopamine on metal ions and constructs multilayer carbon magnetic heterostructures on the surface of carbon fibers through the in situ reduction method, thereby obtaining a new type of multilayer carbon‐based composite absorbing material. The absorption properties at different layers were analyzed and compared through various characterization methods. Finally, the double‐layer structure demonstrated outstanding electromagnetic wave absorption characteristics, exhibiting a wide effective absorption bandwidth of 7.24 GHz and robust absorption of −44.48 dB, all within a mere thickness of 3.5 mm. Therefore, excellent market prospects for this material are anticipated. Highlights: A multilayer carbon magnetic heterostructure absorbing material was constructed on micrometer‐scale carbon fibers. The test results show that a wide effective absorbing bandwidth of 7.24 GHz and a minimum reflection loss of −44.48 dB are obtained when the composite thickness is 3.5 mm.The prepared multilayer absorbing composites can adapt to a variety of application scenarios and have excellent application prospects in the industry.The self‐polymerization of dopamine and complexation of metal ions were used to construct multilayer absorbing materials, and the dielectric loss and magnetic loss capacity of the carbon fibers improved. [ABSTRACT FROM AUTHOR]

This study reveals the impact resistance of shear thickening gel (STG) impregnated four‐layer regular angle interlocking fabrics (AIF) composites. The effects of STG parameters, including reaction time, reaction temperature, and reaction ratio, on the rheological characterization and mechanical properties of STG/AIF flexible composites were investigated. The results show that the increase in STG parameters accelerated the formation of BO crosslink bonds within the STG. The energy storage modulus of STG increased by three orders of magnitude for a reaction temperature of 230°C, a reaction time of 9 h, and a reaction ratio of 12.5%. STG had an obvious shear thickening effect. The coupling effect of STG and AIF increases the inter‐yarn friction. The shear thickening effect of STG and the deformation of AIF fabric synergistically absorbed the impact energy, and the energy absorption rate reached 95.6%. The material surface was not significantly damaged after the low‐velocity impact. The STG/AIF flexible composites showed excellent impact energy absorption properties. Highlights: A new high‐energy absorption and impact resistance composite was prepared.Increased STG reaction ratio and temperature promoted its internal reaction.B and O atomic interactions enhance the rheological properties of STG.STG and fabric synergistically improve the impact resistance. [ABSTRACT FROM AUTHOR]

Herein, poor reproducibility of optical absorption edges in GeS2 glasses and films is seen. Reported spectral positions of the absorption edge in melt‐quenched glasses spread over ≈0.2 eV at ħω ≈ 3 eV. In deposited films, the edge red‐shifts to ħω ≈ 2.5 eV showing wider variations of ≈1 eV. This work considers plausible reasons of such low, spectral reproducibility, with the aid of ab initio molecular orbital analyses of Ge–S clusters and known insights on optical gaps, electron‐spin‐resonance signals, and structural data. The variation in the glass is likely to be governed by several factors including compositional fluctuation, edge/corner‐shared configurations, wrong bonds, and intimate valence‐alternation pairs. The conspicuous red‐shift in the films seems to be affected also by neutral dangling bonds. [ABSTRACT FROM AUTHOR]

Phonon polaritons (PhPs) in hexagonal boron nitride enable sharp midinfrared optical resonance with strong spatial confinement, making them promising for surface‐enhanced infrared absorption (SEIRA) spectroscopy. Here, using colloidal nanosphere lithography, hBN nanopillar antennas are fabricated and their PhP resonances in a cost‐effective way are demonstrated. By varying the diameters of the hBN nanopillars, the PhP resonance can be readily tuned to match the molecular vibrations of CBP (4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl) molecules. Upon frequency matching, the coupling between the PhP resonance and the molecular vibration shows pronounced mode splitting, illustrating the SEIRA behavior with a coupling strength approaching the strong coupling regime. However, with slight frequency mismatching around 10 cm−1, the coupling strength decreases significantly, indicating a high sensitivity of the SEIRA activities to the resonance frequency of hBN nanopillar antennas. The findings provide a new method for the fabrication of PhP nanoantennas and may promote the development of PhPs in SEIRA‐based midinfrared sensing applications. [ABSTRACT FROM AUTHOR]

Porous materials with sound absorption and load‐bearing capabilities are in demand in engineering fields like aviation and rail transportation. However, achieving both properties simultaneously is challenging due to the trade‐off between interconnected pores for sound absorption and mechanical strength. Inspired by quilling art, a novel design using spiral material formed by rolling planar materials into helical structures is proposed. Experimental results show high structural strength through self‐locking mechanisms, while double porosities from interlayer spiral slits and aligned submillimeter pores provide excellent sound absorption. These spiral sheets surpass foam aluminum in specific strength (up to 5.1 MPa) and approach aerogels in sound absorption (average coefficient of 0.93 within 0–6400 Hz). With its adaptability to various planar materials, this spiral design allows for hybrid combinations of different materials for multi‐functionality, paving the way for designing advanced, lightweight porous materials for broad applications. [ABSTRACT FROM AUTHOR]

Experimental characterization of the structural, electronic and dynamic properties of dilute systems in aqueous solvents, such as nanoparticles, molecules and proteins, are nowadays an open challenge. X-ray absorption spectroscopy (XAS) is probably one of the most established approaches to this aim as it is element-specific. However, typical dilute systems of interest are often composed of light elements that require extreme-ultraviolet to soft X-ray photons. In this spectral regime, water and other solvents are rather opaque, thus demanding radical reduction of the solvent volume and removal of the liquid to minimize background absorption. Here, we present an experimental endstation designed to operate a liquid flat jet of sub-micrometre thickness in a vacuum environment compatible with extreme ultraviolet/soft XAS measurements in transmission geometry. The apparatus developed can be easily connected to synchrotron and free-electron-laser user-facility beamlines dedicated to XAS experiments. The conditions for stable generation and control of the liquid flat jet are analyzed and discussed. Preliminary soft XAS measurements on some test solutions are shown. [ABSTRACT FROM AUTHOR]

With the development of ultra‐fast optical technology, the nonlinear interaction between light and matter has attracted great attention. Upconversion laser generation through multiphoton absorption (MPA) enables numerous critical applications such as quantum signal processing, biophotonics, and 3D microfabrication. Herein, an ultra‐low threshold single‐mode four‐photon absorption (4PA) upconversion lasing at room‐temperature (RT) by constructing a strong‐coupling microcavity is demonstrated. The planar microcavity significantly enhances the 4PA nonlinear interaction, which facilitates the obtainment of low‐threshold upconversion lasing with an excellent output divergence angle and beam quality. In addition, the temporal dynamic mechanism and polarization characteristics of single‐mode upconversion lasing are also comprehensively discussed. The work provides a feasible approach to fabricate a low‐threshold single‐mode upconversion laser through high‐order nonlinear MPA processes. [ABSTRACT FROM AUTHOR]

Intramolecular charge transfer (ICT) effects of para‐nitroaniline (pNA) in eight solvents (cyclohexane, toluene, acetic acid, dichloroethane, acetone, acetonitrile, dimethylsulfoxide, and water) are investigated extensively. The second‐order algebraic diagrammatic construction, ADC(2), ab initio wave function is employed with the COSMO implicit and discrete multiscale solvation methods. We found a decreasing amine group torsion angle with increased solvent polarity and a linear correlation between the polarity and ADC(2) transition energies. The first absorption band involves π → π* transitions with ICT from the amine and the benzene ring to the nitro group, increased by 4%–11% for different solvation models of water compared to the vacuum. A second band of pNA is characterized for the first time. This band is primarily a local excitation on the nitro group, including some ICT from the amine group to the benzene ring that decreases with the solvent polarity. For cyclohexane, the COSMO implicit solvent model shows the best agreement with the experiment, while the explicit model has the best agreement for water. [ABSTRACT FROM AUTHOR]

The expected increase in climate change related methane emissions will result in an increase in middle atmospheric water vapor abundance. This will in turn amplify the brightness of noctilucent clouds (NLC). To examine how NLC will impact the absorption of solar radiation, we utilized both an atmospheric background model and a microphysical model spanning the period from 1950 to 2100. At a latitude of 69 ± 3°N, UV absorption at λ = 126 nm is projected to rise from ∼3% to ∼7%. In specific regions, the absorption may spike to approximately 30% by the year 2100. In the visible spectrum, we observe an absorption increase from 0.0030% in 1950 to 0.020% by 2100. Local absorption reach up to 0.35% by the year 2100. These trends are similar at 79 ± 3°N, but are smaller at 58 ± 3°N. Future average absorptions are comparable to solar cycle fluctuations, but local increases are significantly more pronounced. The ice mass contained in NLC is projected to surge from 677 to 1871 tons between 1950 and 2100. Plain Language Summary: Noctilucent clouds (NLC) consist of water ice particles and appear in the summer season in the upper mesosphere at high/middle latitudes where temperatures are very low. Methane is photochemically converted to water vapor in the middle atmosphere. Therefore, the future increase of methane concentration will lead to an increase in water vapor, and to an enhancement of NLC occurrence and brightness. We apply an atmospheric background model and a microphysical ice particle model to study the associated absorption of solar radiation. At 69°N mean absorptions in the UV will increase from ∼3% to ∼7% from 1950 to 2100, respectively. Locally, the absorption can increase to ∼30% in 2100. In the visible (λ = 532 nm) the corresponding numbers are 0.0030% (1950) to 0.020% (2100), that is, an increase by a factor of ∼7, and local maxima up to 0.35% in 2100. Mean absorptions are comparable to variations throughout a solar cycle, but may locally be much larger. Effects on the photochemistry are therefore expected. The total amount of ice mass bound in NLC also increases with time, namely from 677 tons in 1950 to 1871 tons in 2100. NLC will be easier to observe by naked eye, that is, they will be more frequent and brighter. Key Points: Noctilucent clouds (NLC) are ice clouds in the summer mesopause region at middle and polar latitudesThe expected methane related increase in water vapor at NLC heights will lead to more and larger ice particlesLarger ice particles will lead to an enhanced absorption of solar radiation [ABSTRACT FROM AUTHOR]

Achieving broad light absorption and high carrier separation efficiency is crucial for wide‐bandgap semiconductors to enable broadband photodetection applications. Here, amorphous gallium oxide nanosheets feature with broad absorption and spin polarization Wis synthesized, and assembled with graphene and p‐Si, realizing UV‒vis‒NIR photodetection. Extended X‐ray absorption fine structure reveals that a‐GaOx NSs possess lower tetrahedral Ga occupation (10%) compared to crystalline β‐Ga2O3 (50%). UV‒vis‒NIR diffuse reflectance spectra and magnetic hysteresis loops demonstrate broad absorption and weak ferromagnetism of a‐GaOx NSs, respectively. Density functional theory calculation further reveals sub‐gap states and spin polarization in a‐GaOx NSs. Moreover, combined with Mott–Schottky curves, photoluminescence and time‐resolved photoluminescence spectra inferred the effective suppression of carrier recombination via spin polarization of a‐GaOx NSs. The graphene/a‐GaOx NSs/p‐Si photodetector incorporates a back‐to‐back rectifying junction, acquiring a dark current as low as 63 pA. All photogenerated carriers are in the depletion region of the photodetector favouring efficient charge separation. This photodetector exhibits a response time of τrise<60 ms and τfall<120 ms, and high specific detectivity 1013 Jones over 254–1064 nm light. [ABSTRACT FROM AUTHOR]

Transition metal carbides (TMCs) are a class of materialswith excellent dielectric properties and thermal stability, which exhibit enormous potential in high temperature electromagnetic wave absorption (EWA). However, the high dielectric constant and electrical conductivity of TMCs usually cause impedance mismatch, and their high density also prevents further practical applications. To solve these problems, the lightweight and impedance matching NbC nanowires (NbCnws) were prepared by using bamboo powder as a carbon source and subsequent carbothermal reduction reaction process. The as-synthesized NbCnws all exhibit a low density of 0.23 g/cm³ and superior EMA performance. It is worth noting that the minimum reflection loss (RLmin) of the sample is -43.03 dB at 5.92 GHz and the corresponding matching thickness is only 3.7 mm when sintering temperature is 1500°C. The excellent electromagnetic wave absorption (EWA) performance is attributed to good impedance matching and strong dielectric loss. This research work provides a prospect for the development and utilization of one-dimensional TMC materials in the field of microwave absorption materials. [ABSTRACT FROM AUTHOR]

Electromagnetic radiation (EMR) pollution is a serious concern in today's environment, causing problems not just for electronic gadgets but also for living society. The goal of this research is to fabricate thermoplastic polyurethane (TPU) and polypyrrole (PPy)-based 95:5 blend nanocomposites using a simple solvent casting method at such a low concentration of rGO and MWCNT (0.3, 0.4, 0.5 php) (parts per hundred polymers), for electromagnetic wave (EMW) absorption applications. The chemical interaction between the different phases and morphology of the nanocomposites is characterized by Raman spectroscopy, X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM) techniques. The material properties, such as dielectric and magnetic properties, are analyzed in X-band frequency (8.2-12.4 GHz). The total shielding effectiveness of (SETot) 0.5 rGO system is found to be 27 dB, whereas, for corresponding MWCNT nanocomposites, it is 26 dB. Interestingly, in 0.5 rGO nanocomposites, absorption shielding effectiveness (SEAbs) is approximately 25 dB, and reflection shielding effectiveness (SERef) is less than 2 dB, which indicates the absorption of 70% of the electromagnetic wave, and the rest gets reflected. Apart from that, the rGO-based nanocomposites possess a greater extent of thermal stability than the corresponding MWCNT-based nanocomposites. Highlights • Fabrication of TPU-PPy-rGO and TPU-PPy-MWCNT nanocomposites by solvent casting. • Low reflection of TPU-PPy-rGO nanocomposites with a 70% absorption rate. • FESEM confirms the multilayer interface structures. • Tunable Dielectric and magnetic properties of nanocomposites in X-band. • Excellent absorption dominant properties of the fabricated nanocomposites. [ABSTRACT FROM AUTHOR]

Optimization of components and micromorphology regulation are shown to be effective in boosting electromagnetic wave absorption (EMWA). One approach to achieve this enhancement is by utilizing the polarization effects of heterogeneous interfaces. Herein, NiSe2‐CoSe2@C@MoSe2 composites derived from NiCo‐MOF‐74 are fabricated via a facile selenization reaction and subsequent hydrothermal method. By varying the mass ratios of NiSe2‐CoSe2@C and MoSe2, a series of NiSe2‐CoSe2@C@MoSe2 composites with hierarchical flower‐like core–shell structures are obtained. The EMWA properties of the composites display a trend of initially increasing and then decreasing with the increasing content of MoSe2. Interestingly, when the mass ratio of NiSe2‐CoSe2@C and MoSe2 is 3:2, the minimum reflection loss (RL) value is −50.10 dB and an effective absorption bandwidth (RL< −10 dB) value can reach 4.80 GHz (13.20–18.00 GHz). The remarkable EMWA capability can be ascribed to the synergy effects of conductive loss, polarization loss, and suitable impedance matching. This work establishes a new pathway for the synthesis of transition metal dichalcogenides‐based composites, which hold great promise as high‐performance materials for EMWA applications. [ABSTRACT FROM AUTHOR]

Accurate quantification of the absorption properties of brown carbon (BrC) aerosols is crucial to assess the Earth‐atmosphere radiative impacts of BrC. However, the BrC absorption properties were often misestimated in field observations, due to neglecting the contribution of dust absorption. This study solved this problem by coupling a method for calculating the dust concentration into the traditional model for quantifying BrC absorption. The results show that dust absorption was up to 16.8% of the sum of BrC and dust absorption in northwestern China. The potential contribution of dust to the sum of BrC and dust absorption was significantly higher in the Asia‐located studies (0.4%–16.8%) than in the Americas‐located (<1.2%) and Europe‐located (<2.3%) studies. This work underscores the necessity of eliminating the negative effect of dust in BrC quantitative model. It prompts us to revisit the BrC absorption properties resolved by previous studies, especially in dust‐influenced areas such as Asia. Plain Language Summary: Organic components in aerosols that can absorb light are collectively referred to as brown carbon (BrC), and dust aerosols can also absorb light. Their ability to change weather and climate by absorbing solar radiation has received a lot of attention from the academic community. Previous studies have often misestimated the BrC absorption properties because of the difficulty in separating BrC and dust absorption. To solve this difficulty, we proposed a new method to separate the BrC and dust absorption properties, which was successfully applied at a northwestern Chinese site. Subsequently, we found that the contribution of dust to absorption was generally high in the Asia‐located studies, not only in this study, emphasizing the necessity of applying the new method proposed in this study in dust‐affected regions such as Asia. Key Points: A method was developed to remove dust effect when quantifying light absorption properties of brown carbon (BrC)Dust absorption was up to 16.8% of the sum of BrC and dust absorption at a typical site in northwest ChinaAbsorption properties of BrC in dust‐affected areas such as Asia need to be reassessed due to high dust absorption contribution [ABSTRACT FROM AUTHOR]

Although various aerogels with electromagnetic wave (EMW) absorbing properties have been extensively explored, the development of aerogels with excellent wave absorption performance, low density, and great heat resistance has still met profound challenges. Herein, polysilazane hybrid phenolic resin aerogels (PRVS aerogels) were prepared using the vinyl addition reaction of polysilazane and cross‐linking reaction between polysilazane and phenolic resin. A SiOCN ceramic aerogel with multistage pore structure was prepared via a simple and quick freeze‐drying method and polymer‐derived ceramic (PDC) methods. The SiOCN ceramic aerogels exhibited low density (0.15–0.27 g/cm3), good heat‐shielding (thermal conductivity in the range of 0.03–0.04 W/(m·K)), and excellent wave absorption performance (i.e., RL was about –31.6 dB@16.48 GHz and EAB was 3.85 GHz when the thickness of the ceramic aerogel was 1.2 mm). Hence, the ceramic aerogel absorbing materials could meet the requirements of "wide absorption bandwidth, strong reflection loss, lightweight and thi thickness". Moreover, the mechanism of low weight, heat insulation, and wave absorption properties of the aerogels were also investigated. We believe this work is of great significance in ceramic aerogels prepared by traditional polymers, which may provide new opportunities for new ceramic aerogels with applications ranging from EMW absorption to aerospace and information technology. [ABSTRACT FROM AUTHOR]

Nonlinear optical materials hold great promise for applications in advanced opto‐/opto‐electronic devices. However, achieving a substantial nonlinear absorption coefficient and modulation depth concurrently remains challenging. This study proposes an effective strategy for enhancing the nonlinear optical response of materials through the construction of hybrid inorganic–organic superlattices via convenient organic intercalation. Synthesizing SnS2 intercalated with various tetra‐alkylammonium cations, it is revealed that the optimized sample (SnS2/CTA: SnS2 intercalated with cetyltrimethylammonium, CTA+) exhibits a substantial enhancement of nonlinear absorption across a broad wavelength range (from 515 to 1550 nm) and for diverse nonlinear optical processes (saturable absorption, two‐photon absorption, and three‐photon absorption). Specifically, the SnS2/CTA demonstrates a third‐order nonlinear absorption coefficient of (9.847 ± 0.084) × 103 cm GW−1 and a 69% modulation depth under laser excitation at 800 nm. Under 1550 nm excitation, it displays a fifth‐order nonlinear absorption coefficient of (45.3 ± 1.2) cm3 GW−2 and a 62% modulation depth. Notably, these values surpass those of the majority of non‐exfoliated materials. Structural, spectral, and density functional theory calculations indicate no induced structure defects post‐organic intercalation. The observed bandgap reduction is attributed to the electron injection associated with the organic molecule intercalation. The calculated performance enhancement, based on dielectric enhancement and bandgap reduction, qualitatively aligns with experimental findings. [ABSTRACT FROM AUTHOR]