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Two Curcumin (Cur) based mixed ligand complexes of Nickel have been investigated for their optical nonlinearity (NLO). Physicochemical characterization of two nickel precursors and their interaction with curcumin produced two molecules, namely Ni(C3S5)(Cur).2H2O (abbreviated as NiThCur) and NiCl(Cur)(PPh3) (abbreviated as NiTppCur). Additionally the Conceptual‐Density‐Functional‐Theory (CDFT) studies were performed. CDFT‐based optimization parameters of both molecules are theoretically interpreted. HOMO‐LUMO energy gap of NiThCur and NiTppCur were calculated 1.474 eV and 2.744 eV respectively. Both molecules demonstrated good NLO activities, studied by a Z‐scan approach and additionally with a Differential Four wave Mixing (DFWM) technique. Preliminarily investigations showed that the molecules can be potential optical limiters (OL). These studies divulge the exhibition of a 3‐photon absorption (3PA) mechanism by the synthesized molecules. NLO absorption 3PA coefficient (γ) value of 1.34×10−24 m3/W2, third‐order optical susceptibility (χ(3)) value of 1.543×10−11 esu, and the figure of merit 6.64×10−14 esu was observed for the NiThCur complex and γ=3.61×10−24 m3/W2, χ(3)=1.521×10−11 esu, and FoM=5.61×10−14 esu for NiTppCur with Z‐scan (γ and χ(3)) and DFWM methods, respectively. Normalized transmittance (NT) exhibited a decrease to 78.5 % from 100 % in NiThCur and to 69.5 % in NiTppCur. Optical limiting calculations are also presented. [ABSTRACT FROM AUTHOR]

The structural dependence of nonlinear optical properties associated with ADP-doped PVA/PVP polymer composites is discussed in this work. Polymer composites are fabricated using the solution casting method. X-ray diffraction (XRD) was used to perform structural analysis on these samples whose average crystallite size increases with an increase in dopant concentration. Results from UV–Vis–NIR spectra show that the samples are transparent in the IR region. The Z-scan technique was established by following the method described by Sheik-Bahae et al. The shape of the open aperture plot suggests that the samples exhibit two-photon absorption. The NLO properties such as nonlinear absorption coefficient (β) , two-photon absorption cross-section ( σ 2) and the imaginary part of third-order nonlinear susceptibility (χ (3)) were investigated at 1064 nm and these values were found to be in the order of ∼ 1 0 − 7 W/cm, ∼ 1 0 − 2 0 cm4/GW and ∼ 1 0 − 1 4 esu, respectively. The open aperture Z-scan method yielded optical limiting data, from which the optical limiting threshold was calculated to be in the order of ∼ 1 0 1 3 W/m2. Functional data analysis uses a suitable basis representation to assess the functional correlation between global and local variables. [ABSTRACT FROM AUTHOR]

A first-principles method was used to explore the influence of tensile strain on the electrical and optical characteristics of Nb-doped MoSe2. The tensile strain has been discovered to have a higher influence on the electrical structure of the Nb-doped MoSe2 system than pure monolayer MoSe2. According to the energy band structure study, the pure monolayer MoSe2 is a direct bandgap semiconductor, but the system doped with Nb instead of Mo atoms is a p-type-doped semiconductor. The bandgap of the Nb-doped MoSe2 system decreases gradually with the increase of tensile strain, but still maintains the p-type semiconductor properties, and the bandgap of the pure monolayer MoSe2 also decreases gradually with the increase of tensile strain. From the density of states analysis, it is found that for the total density of states of the doped system at different tensile strains, it is mainly contributed by the Mo-4d and Se-4p orbitals. The optical properties analysis showed that the doped system under tensile strain had higher absorption coefficient and reflectance peak than the Nb-doped MoSe2 system without tensile strain. Additionally, the doped system showed redshift phenomenon in both the absorption and reflection peaks as the tensile strain increased. [ABSTRACT FROM AUTHOR]

Density functional theory was employed to investigate the structural, electronic, elastic, thermodynamic, and thermoelectric characteristics of RhNbZ (Z = Si, Ge) half-Heusler materials. Furthermore, RhNbZ (Z = Si, Ge) alloys adhere to the semiconductor behaviour dictated by the Slater–Pauling rule. Elastic property calculations affirm the mechanical stability of the compounds. Next, we use density functional perturbation theory (DEPT) to predict the dynamical context of these ordered systems. Utilizing the Debye quasi-harmonic model, we explored the thermodynamic properties of these half-Heusler alloys. The thermoelectric properties of the materials were evaluated using the semi-classical Boltzmann theory, which was implemented in the BoltzTraP code. A remarkably high figure of merit values for RhNbZ (Z = Si, Ge) compounds suggests their potential for thermoelectric applications across a wide temperature range. Optical properties, including dielectric function, absorption coefficient, refractive index, reflectivity, and optical conductivity, were calculated and discussed. Notably, the materials exhibit exceptional absorption coefficients α(ω) in the ultraviolet and visible regions of the light spectrum, indicating their suitability for applications in photovoltaic and optical equipment manufacturing. [ABSTRACT FROM AUTHOR]

Porous sound absorption ceramic is one of the most promising materials for effectively eliminating noise pollution. However, its high production cost and low mechanical strength limit its practical applications. In this work, low-cost and in situ mullite whisker-reinforced porous sound-absorbing ceramics were prepared using recyclable construction waste and Al2O3 powder as the main raw materials, and AlF3 and CeO2 as the additives, respectively. The effects of CeO2 content, AlF3 content, and sintering temperature on the microstructure and properties of the porous ceramics were systematically investigated. The results showed that a small amount of CeO2 significantly promoted the growth of elongated mullite crystals in the resultant porous ceramics, decreased the growth temperature of the mullite whiskers, and significantly increased the biaxial flexural strength. When 2 wt.% CeO2 and 12 wt.% AlF3 were added to the system, mullite whiskers were successfully obtained at a sintering temperature of 1300 °C for 1 h, which exhibited excellent properties, including an open porosity of 56.4 ± 0.6%, an average pore size of 1.32–2.54 μm, a biaxial flexural strength of 23.7 ± 0.9 MPa, and a sound absorption coefficient of >0.8 at 800–4000 Hz. [ABSTRACT FROM AUTHOR]

Ternary chalcogenides have emerged as potential candidates for ultrathin photovoltaics, and NaBiS2 nanocrystals (NCs) have gained appeal because of their months‐long phase‐stability in air, high absorption coefficients >105 cm−1, and a pseudo‐direct bandgap of 1.4 eV. However, previous investigations into NaBiS2 NCs used long‐chain organic ligands separating individual NCs during synthesis, which severely limits macroscopic charge‐carrier transport. In this work, these long‐chain ligands are exchanged for short iodide‐based ligands, allowing to understand the macroscopic charge‐carrier transport properties of NaBiS2 and evaluate its photovoltaic potential in more depth. It is found that ligand exchange results in simultaneous improvements in intra‐NC (microscopic) and inter‐NC (macroscopic) mobilities, while charge‐carrier localization still takes place, which places a fundamental limit on the transport lengths achievable. Despite this limitation, the high absorption coefficients enable ultrathin (55 nm thick) solar absorbers to be used in photovoltaic devices, which have peak external quantum efficiencies > 50%. In addition, temperature‐dependent transient current measurements uncover a small activation energy barrier of 88 meV for ion migration, which accounts for the strongly hysteretic behavior of NaBiS2 photovoltaic devices. This work not only reveals how the charge‐carrier transport properties of NaBiS2 NCs over several length and time scales are influenced by ligand engineering, but also unveils the facile ionic transport in this material, which limits the potential of NaBiS2 in photovoltaics. On the other hand, the discovery shows that there are opportunities to use this material in memristors, electrolytes, and other applications requiring ionic conduction. [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]

The lack of a bandgap in stanene severely limits its outstanding characteristics in optoelectronic devices. Using first-principles calculations, we systematically investigate the effects of full hydrogenation and shear deformation on the electronic structure and optical properties of stanene. Hydrogenation exerts a remarkable impact on electronic structure of stanene, enabling surface state transition from quasi-metallic to semiconducting. Shear degrades the structural stability of full-hydrogenated stanene (FHstanene). FHstanene exhibits a tunable bandgap of 1.327 eV, which can be further reduced to 0.719 eV through shear deformation. The presence of spin-orbit coupling (SOC) induces band splitting in FHstanene. The maximum optical absorption of FHstanene occurs at 291 nm, while the reflectance peak is observed at 449 nm. The variation in bandgap due to deformation results in a redshift in the absorption coefficient and reflectance, and shear deformation increases the reflectance of FHstanene. These findings broaden the application prospects of stanene in novel nano-optoelectronic devices. [ABSTRACT FROM AUTHOR]

Photosensitizers that are good producers of singlet oxygen, and the photocatalytic reactions promoted by these photosensitizers, have always been of great interest. In this study, we aimed to develop new photosensitizers based on cyclotriphosphazene and evaluate their performance in photocatalytic reactions. In this context, three new cyclotriphosphazene derivatives, each bearing BODIPY and thiophene units, were synthesized, and their molecular structures were characterized using spectroscopic techniques. Both the BODIPY derivatives and their cyclotriphosphazene derivatives had absorption in the visible region, and also, the resulting cyclotriphosphazene compounds exhibited significantly better molar absorption coefficients compared to the precursor BODIPY units. Incorporation of the halogen atom into the molecules resulted in the redshift of absorption and emission maxima, as well as decrease in the fluorescence characteristics of these molecules. The singlet oxygen-producing abilities of the molecules were evaluated by the chemical trapping method using DPBF as the singlet oxygen scavenger molecule, and the change was monitored by UV-vis absorption spectroscopy. Cyclotriphosphazene compounds 7 and 8 performed significantly better than both methylene blue and their precursor units, with singlet oxygen quantum yield values of 0.85 and 0.91. Finally, the ability of these compounds to convert 1,3-cyclohexadiene into peroxides (2,3-dioxabicyclo[2.2.2]oct-5-ene and 3-hydroperoxycyclohexa-1,4-diene) was evaluated. The compounds displayed notable photocatalytic activity toward the oxidation of 1,3-cyclohexadiene compared to tetraphenyl porphyrin (TPP), a known photocatalyst. [ABSTRACT FROM AUTHOR]

Cation disorders refer to the phenomenon where cations are randomly distributed in multi‐cation systems. These disorders have emerged as an effective strategy for tailoring material properties across diverse applications. Notably, engineering cation disorder in AgBiS2 has garnered attention, owing to its remarkable enhancement of light absorption coefficients, which are crucial for efficient solar energy conversion in ultrathin light absorber layers. In this study, a novel dithiocarbamate (DTC)‐based solution processing method designed to control cation disorder is presented in AgBiS2 thin films. Unlike conventional approaches that rely on heat treatment, the strategy is based on molecular coordination dynamics between DTC and metal cations. By adjusting the ratio of DTC to the metal cations, the formation of cation‐disordered AgBiS2 thin films is demonstrated. Notably, the order‐to‐disorder transition is solely dependent on the DTC‐metal coordination and independent of the annealing temperature. These disordered films exhibit a high light absorption coefficient (>5 × 105 cm−1), mirroring the characteristics of thermally‐treated cation‐disordered AgBiS2 nanocrystals reported previously. The disordered AgBiS2 thin‐film photodetector exhibited a higher photocurrent density and responsivity compared to its ordered counterpart. The approach establishes a novel platform for cation disorder engineering, paving the way for advancements in cation‐disordered materials with diverse applications. [ABSTRACT FROM AUTHOR]

Copper indium sulfide quantum dots (CIS QDs) possess the desired optical properties to act as photoanodic material in photoelectrochemical cells, like a high molar absorption coefficient over the entire visible spectrum and long exciton lifetimes. The already reported procedures that utilize photoanodes based on such nanoparticles, however, exploit harsh conditions or utilize non‐scalable, expensive, and low‐yield syntheses. Here, the construction of CIS QDs adsorbed onto TiO2/FTO photoanodes (FTO = fluorine‐doped tin oxide) with a process aimed at avoiding these issues is proposed. In particular, the employment of dihydrolipoic acid as the ligand allows an easy and cost‐effective functionalization. CdS layers are deposited onto the nanoparticles to enhance the photoelectrochemical properties. Full characterization of the steady–state and transient photoelectrochemical properties of the electrodes is performed to gain information on the interfacial dynamics among the different components of the electrode. Maximum IPCEs of the order of 50% and a spectral sensitization extended up to 700 nm are obtained in the optimized conditions. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h‐BN) is a van der Waals (vdW) ultrawide bandgap semiconductor with high band‐edge absorption coefficient and chemical/thermal resistance, demonstrating great potential for vacuum ultraviolet (VUV) and UV‐C detection. Hitherto, most of their prevailing applications have exploited epitaxial films and multilayers either grown on substrates or transferred, which tend to form energy‐favorable noncovalent vdW epitaxy. Here, an alternative heteroepitaxy of 2‐inch h‐BN is reported with desirable thickness and vertically aligned vdW layers covalently bonded to sapphire, enabled by activating the inert substrate surface using ion impingement during deposition and the dislocation‐mediated epitaxial transition. The fabricated photodetectors allow efficient photon absorption and carrier collection using a simple planar device design, showing excellent VUV/UV‐C detection performance with ultrafast response of 270 ns/60 µs (rise/decay) and remarkable operating stability until 500 °C. This covalent heteroepitaxy of wafer‐scale h‐BN opens new avenues for optoelectronics and electronics significant to harsh environment applications. [ABSTRACT FROM AUTHOR]

Recently, transition metal dichalcogenide photocatalysts have been substantially explored as efficient catalysts for water splitting. This paper systematically investigates the electronic structure and related properties of four, hitherto uninvestigated, Janus MoSSe/Ga 2 SSe vdW heterostructures using first-principles calculations. The results indicate that two out of the four heterostructures exhibit a type-II energy band arrangement, which facilitates the effective separation of electron-hole pairs in space. Additionally, the electrostatic potential, charge density difference and Bader charges analyses indicate that charge transfer in the interfacial region creates a built-in electric field that effectively inhibits electron and hole complexation, and that one out of the four heterostructures corresponds to a direct Z-scheme heterojunction. The optical absorption coefficients show that the MoSSe/Ga 2 SSe vdW heterostructures have a broad absorption range from visible to ultraviolet. These findings suggest that the Janus SMoSe/SGa 2 Se and SMoSe/SeGa 2 S vdW heterostructures could be suitable for photocatalytic water decomposition. The SMoSe/SGa 2 Se and SMoSe/SeGa 2 S vdW heterostructures have high corrected solar-to-hydrogen (STH) efficiency of 11.84% and 10.13%, respectively. [Display omitted] • Two Janus MoSSe/Ga 2 SSe vdW heterostructures are found type-II heterojunctions. • One of the type-II heterojunctions is a candidate as direct Z-scheme photocatalyst. • The built-in electric field can promote the separation of charge carriers. • Heterostructures band positioning are suitable for water splitting. • The heterostructures exhibit a broad absorption range from visible to ultraviolet. [ABSTRACT FROM AUTHOR]

Today, municipal solid waste (MSW), noise pollution and fire attack are three ongoing issues for inhabitants of urban including in Malaysia. To solve these issues, an eco-friendly autoclaved aerated concrete (AAC) containing recycled ceramic and gypsum waste (CGW) as partial replacement for sand with different ratios (0%, 5%, 10%, 15%, 20% and 25% wt) have been prepared. The work density (ρw) and mechanical properties of samples such as compressive strength (fc) and specific strength (S) have been investigated. The functional properties of samples such as sound absorption coefficient (SAC) and direct fire resistance also have been carried out. All samples showed normal color behavior i.e. grey and free crack with a ρw was in the range of 593.71 kg/m³ to 605.29 kg/m³. The fc increased in the range of 6.10% to 29.88%. The maximum value of fc was 2.13 MPa for 15% wt of CGW. The SAC of samples at low frequency (500 Hz) is higher than reference sample (RS). All AAC-CCW samples are categorized as material class B and C absorbers at frequency 500 Hz. Except for RS, the fire resistance results showed the physical surface of the samples had free crack and not burned during direct fire at 950°C for 300 s. The results showed that CGW have positive effect on the mechanical and functional properties of AAC. [ABSTRACT FROM AUTHOR]

Increasing wideband absorption in crystalline silicon (c-Si) solar cells is a task that is vital in order to improve the power conversion efficiency of the device. The low light absorption of incident photons is discovered in this type of solar cell due to the bulk c-Si indirect band gap as well as low absorption coefficient characteristics. This work reports on the micro-texture size influence towards enhancing wide/broadband light absorption in hybrid microtextured/nanotextured c-Si for solar cell applications. Sodium hydroxide (NaOH) solution is used to fabricate a Microscale pyramid on c-Si. The NaOH etching is performed at different durations between 25-40 min. The one step silver-assisted wet chemical etching (one-step AgNO3-based MACE) method is applied to prepare nanowires on the pyramid. After 30 min of etching, a range of pyramids with heights between 3-7 µm and 3-10 µm of widths are formed. After the one-step AgNO3-based MACE, nanowires with 300-800 nm heights and 40-50 nm widths are obtained on the pyramids. After the fabrication of nanowires on the pyramids, considerable suppressed weighted average reflection (WAR) is obtained in all the samples, due to improved light trapping and augmented light scattering by the nanowires and the base pyramids respectively. Lowest broadband reflection (9.0 % WAR), is obtained after 30 min of etching and 80 s one-step AgNO3-based MACE. This translates to 38.9 mA/cm² maximum short-circuit current density (maximum Jsc), or 14.1% improvement compared to the maximum Jsc of the pyramids without nanowires (34.1 mA/cm²). The findings indicated that the hybrid textured surface in c-Si is a promising approach to enhance wideband light absorption and potential photocurrent for application in photovoltaic devices. [ABSTRACT FROM AUTHOR]

In the course of this investigation, we performed ab initio calculations. The investigation systematically explored the physical features of chalcopyrite-phase BeXAs2 (X=Sn and Ge). Total energy calculations incorporated the Wu-Cohen generalized gradient approximation (WC-GGA) [1] to consider the exchange-correlation potential. The analysis of band structures employed the modified Becke Johnson (mBJ) [2] potential approximation, renowned for its effectiveness in addressing concerns related to band gaps. The optical properties of these materials were further elucidated through the determination of the dielectric function and absorption coefficient. The analysis of electronic and optical characteristics underscores the potential applications of BeXAs2 compounds in photonics, optoelectronics, and photovoltaics. Notably, the results exhibit strong agreement with both prior theoretical investigations and experimental data. [ABSTRACT FROM AUTHOR]

The growing amount of used tires presents many environmental challenges around the world. Therefore, new ways to reuse used tires are being sought. One of the uses of waste tires is in sound-insulating constructions. Waste tires can be shredded into granules, which can be further devulcanized to increase their porosity. These granules can then be glued to panels and used in sound-insulating structures. Acoustic louvers were investigated in this study, with the louvers’ plates covered with rubber granule panels. Sound absorption parameters of rubber granule panels were tested across frequency bands ranging from 160 Hz to 5000 Hz. The results showed the normal incidence sound absorption coefficient reached 0.87–0.96 at 3150 Hz for 12 mm rubber granule plates. Measurements were conducted in a semi-anechoic chamber. The study has shown that rubber louvers can reduce the sound pressure level by 8 dB–12 dB, depending on the composite of the rubber granule panels and the tilt angle of the louvers’ plates. [ABSTRACT FROM AUTHOR]

Fish possess lipases from embryonic development to adulthood. Lipase activity methods vary and significantly differ in terms of the concentration of the substrate used, bile salt, Ca2+, temperature, pH, and type of lipase units, which limits comparative studies. The three most-used substrates are p-nitrophenyl (p-NP), β-naphthyl (β-N) derivates, and emulsified natural oils. These were selected to be redesigned in this study to measure lipase activity under temperature, pH, ion, and bile salt conditions closer to fish physiology, using the appropriate molar absorption coefficient to calculate the lipase units. Cynoscion parvipinnis (CP), Seriola rivoliana (SR), Centropomus viridis (CV), Elop affinis (EA), and Canthidermis maculate (CM) pyloric caeca-intestine extracts were studied. Sodium taurocholate showed the highest activity for intestinal lipases, and the fatty acid length in the substrates changed the lipase hydrolysis rate. The highest lipase activity was obtained with p-NP butyrate and p-NP caprylate in four fish species. Lipase activity was highly activated with Ca2+ (4–7 mM). The β-N absorption spectrum indicates a plateau between 534 and 554 nm for fish lipases. Salmon oil was identified as the most digestible lipid in the four fish species using the in vitro digestibility assay. The lipase zymogram showed an apparent size of 46.3 kDa for CP, 40.2 kDa for SR, 46.2 kDa for CM, 106.6 kDa for EA, and 58.3, 84.6, and 162.1 kDa for CV. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate some characteristics of thermally treated Scots pine (Pinus sylvestris L.) wood specimens such as air-dried density, color change, average surface roughness, and sound absorption capacity. Heat treatment of Scots pine wood was performed at atmospheric pressure at 140, 160, 180, and 200 °C for 2 h. As a result, the air-dried density values of the thermally treated wood decreased as the temperature of the thermal treatment increased. With the increase of thermal treatment temperature, an increase in total color change values was detected on the surfaces of the samples and the color of the samples became darker. The average surface roughness (Ra) value of samples improved due to thermal treatment conditions and the highest value was determined in thermally treated samples at 200 °C as 3.59 µm. At 140 °C the value of maximum sound absorption coefficient was observed to be 0.48 at 2500 Hz and the highest sound transmission loss value, which was 36.7 dB, was measured at 6300 Hz and at 200 °C. [ABSTRACT FROM AUTHOR]

A detailed analysis of the previously discovered effect of the concentration of phosphotungstic acid (PTA) on its reduction within nanocomposite films with poly(vinyl alcohol) (PVA) induced by gamma radiation indicated that the molar absorption coefficient of the maximum of the PTA band due to intervalence charge transfer in reduced PTA heteropolyanions at low PTA concentrations is eight times higher than at high concentrations. Only 20% of this increase is attributed to the predominance of two- and one-electron-reduced heteropolyanions at low and high concentrations, respectively. We concluded that the main reason for the concentration effect is associated with a decrease in the size the PTA nanoparticles with decreasing PTA concentration in the films. [ABSTRACT FROM AUTHOR]

The bactericidal components of air plasma jets generated by a direct-current glow discharge and a dielectric barrier discharge were studied using IR and UV absorption spectroscopy. The mole fractions of bactericidal components with an absorption spectrum band structure were determined by selecting a mole fraction value in the calculated spectrum that ensured correlation with the experimental spectrum. The spectra were calculated using the HITRAN spectral database and the Specair 3.0 program. The error in the mole fractions due to violation of the Bouguer–Lambert–Beer law when using absorption coefficients convoluted with the instrument function was determined. The mole fractions of bactericidal components with a continuous absorption spectrum were calculated using the Bouguer–Lambert–Beer law in a standard way. IR and UV absorption spectroscopy were shown to enable determination of the mole fractions for the full set of bactericidal components in air plasma jets of glow and barrier discharges. [ABSTRACT FROM AUTHOR]

A stepped-type multi-cavity combined sound absorber (SMCSA) was developed to improve the low and mid-frequency sound absorption capabilities of micro-perforated panels. The sound absorption characteristics of the SMCSA were thoroughly investigated using experimental methods, theoretical calculations, and numerical simulation. The particle swarm optimization algorithm was employed to optimize the SMCSA parameters. The findings revealed that the board thickness, hole size, and cavity depth significantly influenced the sound absorption properties of the SMCSA. When the hole size ranged from 0.4–0.6 mm, the sound absorption coefficient of the SMCSA reached 0.9, and the resonance frequency was 600–800 Hz. After optimization utilizing the hybrid particle swarm algorithm, the maximum sound absorption coefficients at the resonance frequency of the two-step, four-step, and eight-step structures were all 0.99. [ABSTRACT FROM AUTHOR]

Chromophoric dissolved organic matter (CDOM) is a mixture of various types of organic matter and a useful parameter for monitoring complex inland surface waters. Remote sensing has been widely utilized to detect CDOM in various studies; however, in many cases, the dataset is relatively imbalanced in a single region. To address these concerns, data were acquired from hyperspectral images, field reflection spectra, and field monitoring data, and the imbalance problem was solved using a synthetic minority oversampling technique (SMOTE). Using the on-site reflectance ratio of the hyperspectral images, the input variables Rrs (452/497), Rrs (497/580), Rrs (497/618), and Rrs (684/618), which had the highest correlation with the CDOM absorption coefficient aCDOM (355), were extracted. Random forest and light gradient boosting machine algorithms were applied to create a CDOM prediction algorithm via machine learning, and to apply SMOTE, low-concentration and high-concentration datasets of CDOM were distinguished by 5 m−1. The training and testing datasets were distinguished at a 75%:25% ratio at low and high concentrations, and SMOTE was applied to generate synthetic data based on the training dataset, which is a sub-dataset of the original dataset. Datasets using SMOTE resulted in an overall improvement in the algorithmic accuracy of the training and test step. The random forest model was selected as the optimal model for CDOM prediction. In the best-case scenario of the random forest model, the SMOTE algorithm showed superior performance, with testing R2, absolute error (MAE), and root mean square error (RMSE) values of 0.838, 0.566, and 0.777 m−1, respectively, compared to the original algorithm's test values of 0.722, 0.493, and 0.802 m−1. This study is anticipated to resolve imbalance problems using SMOTE when predicting remote sensing-based CDOM. It is expected to produce and implement a machine learning model with improved reliable performance. [ABSTRACT FROM AUTHOR]

The validation of a feasible application for the production of sustainable bricks with local materials in humid and hot climates, which would allow the current housing needs of a constantly growing population with scarce economic resources to be met while also reducing energy inputs for climate control, is a current challenge without a definitive solution. Therefore, this research studied the incorporation of local aggregates and two second-generation materials to produce lime-stabilized Compressed Earth Blocks (CSEBs) using a semi-automatic machine for their manufacture. An initial matrix was designed as a baseline, and three more were developed with variations to incorporate second-generation materials individually and as mixtures. The stabilizer was added in concentrations of 5, 10, and 15%, resulting in a total of 12 batches of CSEBs. Eleven of the studied batches exceed the normative limits for simple compressive strength and initial water absorption coefficient. The best result of simple compressive strength was obtained in two batches of the same matrix that used construction demolition waste (CDW), reaching 4.3 MPa (43% above the minimum limit established by the most restrictive regulations and 115% above the least restrictive). It was possible to produce sustainable bricks in situ with average ambient temperatures of 32 °C and relative humidity of 91%. [ABSTRACT FROM AUTHOR]

The purpose of this study was to empirically evaluate the performance of fibrous materials that meet the criteria for inlet air filtration in internal combustion engines. The characteristics of filtration efficiency and accuracy, as well as the characteristics of flow resistance, were determined based on the mass of dust accumulated in the filter bed during the filtration process. Single-layer filter materials tested included cellulose, polyester, and glass microfiber. Multilayer filter media such as cellulose–polyester–nanofibers and cellulose–polyester were also examined. A new composite filter bed—consisting of polyester, glass microfiber, and cellulose—and its filtration characteristics were evaluated. Utilizing specific air filtration quality factors, it was demonstrated that the composite is characterized by high pre-filtration efficiency (99.98%), a short pre-filtration period (qs = 4.21%), high accuracy (dpmax = 1.5–3 µm) for the entire lifespan of the filter, and a 60–250% higher dust absorption coefficient compared to the other tested materials. A filtration composite bed constructed from a group of materials with different filtration parameters can be, due to its high filtration efficiency, accuracy, and dust absorption, an excellent filter material for engine intake air. The composite's filtration parameters will depend on the type of filter layers and their order relative to the aerosol flow. This paper presents a methodology for the selection and testing of various filter materials. [ABSTRACT FROM AUTHOR]

In this work, a dielectric barrier discharge (DBD) based exciplex lamp emitting radiation at far UV-C wavelength 222 nm has been reported. The developed UV source has been used for the degradation of organic micropollutants (OMPs), i.e., brilliant red 5B (BR-5B) and sulfamethoxazole (SMX) in a batch-scale reactor. The degradation of OMPs has been performed using an advanced oxidation process by loading hydrogen peroxide (H2O2) as a radical promotor. The degradation efficiency and energy yield in the case of BR-5B have been found twofold as compared to SMX at similar experimental conditions, because of its high molar absorption coefficient at 222 nm radiation. [ABSTRACT FROM AUTHOR]

The 1D moisture diffusivity of porous materials may strongly depend on the content of moisture in the materials, varying over an order of magnitude or more. In this paper we present a new model from which the diffusivity can be evaluated, using the pore size distribution and water absorption coefficient. We point out that this is a more efficient approach than the standard Boltzmann–Matano (BM) method, because measurements of pore curves and water absorption are much shorter and rather accurate compared to moisture profile experiments needed in the BM method. As an example, we apply our model to two samples of a ceramic brick for which experimental data on both pore curves and moisture profiles had been measured. A very good quantitative agreement in the diffusivity is obtained for early stage profiles. For later stages, however, the model predicts three to four times higher diffusivity than the BM method. The reasons for this discrepancy are discussed and further tasks to validate the effectiveness of the new model are proposed. We also compare our model with the pore models of Burdine and Mualem. [ABSTRACT FROM AUTHOR]

The high-salt fog environment under a marine climate affects the capillary water absorption performance of porous building materials, causing changes in the thermal and wet properties of the materials and in their structural durability. Therefore, a capillary water absorption experiment of coral sand concrete (CSC) in different salt solution concentrations was designed in this study. The experimental results showed that salt had the effect of first promoting and then inhibiting capillary water absorption coefficient (Acap) with increased salt solution concentration. Salt had the effect of promoting liquid diffusivity (Dl). In addition, by analyzing the surface tension and viscosity of a sodium chloride solution, the mechanism of the influence of liquid properties on Acap was briefly explored. The results provide a theoretical basis for the establishment of a coupled heat and moisture transfer model of porous building materials in marine climates. [ABSTRACT FROM AUTHOR]

This study explored the influence mechanism on the water resistance of magnesium phosphate repair mortars. The fluidity, setting time, mechanical properties, water resistance, and interfacial bonding strength of red mud–modified magnesium phosphate repair mortars (RMPMs) were systematically investigated. Through capillary absorption tests, the effect of the water-binder ratio (W/B) on the water transfer characteristics was explored, and then the actuating mechanism of capillary porosity and capillary absorption coefficients on water resistance was clarified. The results show that the fluidity and setting time of RMPM increase with the increase of W/B. When W/B increased from 0.18 to 0.20, the compressive strength, flexural strength, strength retention, and interfacial bonding strength of RMPM changed little and decreased linearly. And the interfacial bonding strength of RMPM was significantly reduced after 7 days of water curing. The capillary water absorption of RMPM was linear with the square root of time. The capillary absorption coefficient and capillary porosity of the RMPM increased greatly with increasing W/B when the W/B is between 0.20 and 0.28, while the water resistance, mechanical properties, and interfacial bonding property decreased linearly. Variations in W/B changed the capillary pore characteristics of the RMPM, which in turn affected the mechanical properties, capillary water absorption characteristics, and water resistance. [ABSTRACT FROM AUTHOR]

This compendium review focuses on the spatial distribution of sensitivity to localized absorption changes in optically diffuse media, particularly for measurements relevant to near-infrared spectroscopy. The three temporal domains, continuous wave, frequency domain, and time domain, each obtain different optical data types whose changes may be related to effective homogeneous changes in the absorption coefficient. Sensitivity is the relationship between a localized perturbation and the recovered effective homogeneous absorption change. Therefore, spatial sensitivity maps representing the perturbation location can be generated for the numerous optical data types in the three temporal domains. The review first presents a history of the past 30 years of work investigating this sensitivity in optically diffuse media. These works are experimental and theoretical, presenting one-, two-, and three-dimensional sensitivity maps for different Near-Infrared Spectroscopy methods, domains, and data types. Following this history, we present a compendium of sensitivity maps organized by temporal domain and then data type. This compendium provides a valuable tool to compare the spatial sensitivity of various measurement methods and parameters in one document. Methods for one to generate these maps are provided in Appendix A, including the code. This historical review and comprehensive sensitivity map compendium provides a single source researchers may use to visualize, investigate, compare, and generate sensitivity to localized absorption change maps. [ABSTRACT FROM AUTHOR]

The combined cooling, heating, and power (CCHP) system has attracted increasing attention due to its potential outstanding performance in thermodynamics, economics, and the environment. However, the conventional CCHP systems are carbon-intensive. To solve this issue, a low-carbon-emission CCHP system (LC-CCHP) is firstly proposed in this work by integrating a sorption-enhanced steam methane reforming (SE-SMR) process. In the LC-CCHP system, CO2 is continuously captured by the calcium loop so that low-carbon energy can be generated. Then, the LC-CCHP system thermodynamic model, mainly consisting of a dual fluidized bed reactor which includes the SE-SMR reactor and a CaCO3 calcination reactor, a hydrogen gas turbine, a CO2 reheater, and a lithium bromide absorption chiller, is built. To prove that the LC-CCHP model is reliable, the system major sub-unit model predictions are compared against data from the literature in terms of thermodynamics and economics. Finally, the effects of reforming temperature (Tref), the steam-to-carbon mole ratio (S/C), the calcium-to-carbon mole ratio (RCC), the equivalent ratio for gas turbine (RAE), and the hydrogen separation ratio (Sfg) on total energy efficiency ( η t e n ), total exergy efficiency ( η t e x ), and carbon capture capability ( R c m ) are detected. It is found that the minimum exergy efficiency of 64.5% exists at the calciner unit, while the maximum exergy efficiency of 78.7% appears at the gas turbine unit. The maximum energy efficiency and coefficient of performance of the absorption chiller are 0.52 and 1.33, respectively. When T r e f = 600 °C, S / C = 4.0 , R C C = 7.62 , R A E = 1.20 , and S f g = 0.27 , the η t e n , η t e x , and R c m of the system can be ~61%, ~68%, and ~96%, and the average specific cost of the system is 0.024 USD/kWh, which is advanced compared with the parallel CCHP systems. [ABSTRACT FROM AUTHOR]

As one of the most promising photovoltaic technologies, perovskite solar cells (PSCs) exhibit high absorption coefficients, tunable bandgaps, large carrier mobilities, and versatile fabrication techniques. Nevertheless, the commercialization of the technology is hindered by poor material stability, short device lifetimes and the scalability of fabrication techniques. To address these technological drawbacks, various strategies have been explored, with one particularly promising approach involving the formation of a low-dimensional layer on the surface of the three-dimensional perovskite film. In this work, we demonstrate the use of guanidinium tetrafluoroborate, CH6BF4N3, (GATFB) as a post-treatment step to enhance the performance of PSCs. Compared with the control sample, the application of GATFB improves the film surface topology, reduces surface defects, suppresses non-radiative recombination, and optimizes band alignment within the device. These positive effects reduce recombination losses and enhance charge transport in the device, resulting in PSCs with an open-circuit voltage (VOC) of 1.18 V and a power conversion efficiency (PCE) of 19.7%. The results obtained in this work exhibit the potential of integrating low-dimensional structures in PSCs as an effective approach to enhance the overall device performance, providing useful information for further advancement in this rapidly evolving field of photovoltaic technology. [ABSTRACT FROM AUTHOR]

Herein, the structural, electronic, optical, and mechanical properties of Cu(I)Au(III)‐based double perovskites using first‐principles calculations are investigated. Phonon calculation results confirm that pure halide Cs2CuAuX6 (X = Cl, Br), mixed‐halide Cs2CuAuBr4Cl2 and Cs2CuAuI4Br2, and strained Cs2CuAuI6 (by 3% strain) are dynamically stable. Subsequently, the optoelectronic and mechanical properties of these compounds are calculated. The calculations reveal that Cs2CuAuX6 exhibits slightly indirect‐bandgap semiconducting behavior, with the bandgaps of 1.169, 1.191, and 1.355 eV from the HSE06 hybrid functional for X = Cl, Br, and I, respectively. Meanwhile, the bandgap of Cs2CuAuI6 decreases with the increase of strain from 1% to 3% (1.271, 1.148, and 1.037 eV, respectively). In addition, the results show that Cs2CuAuI4Br2 (EgHSE06 = 1.278 eV) has a suitable bandgap, which is close to the ideal direct bandgap. Moreover, Cs2CuAuI4Br2 exhibits strong anisotropic visible light absorption with absorption coefficients exceeding 105 cm−1 and has a relatively large dielectric constant (εxxst = εyyst = 36.27) along the ab plane. Furthermore, its Pugh's ratio (Poisson's ratio) value of 2.94(0.35) exceeds the critical value of 1.75(0.26), indicating its ductility and potential for use in flexible electronic devices. [ABSTRACT FROM AUTHOR]

The advancement of acoustic metamaterials enables the highly efficient absorption of low-frequency noise with a subwavelength structure thickness, but the complexity of these structures often hinders their large-scale practical applications. Here, we propose a straightforward and compact acoustic metamaterial structure composed of Helmholtz resonators with side slits (HRSS) for low-frequency noise absorption. The introduction of side slits not only simplifies the overall structure but also allows for easy adjustment of acoustic characteristics. By adjusting the depth of the resonator within the slit across 25 distinct units, an absorption coefficient above 0.8 is realized from 470 to 930 Hz. This work demonstrates the extensive low-frequency sound absorption capability of HRSS, providing valuable insights into the design of future practical acoustic materials. [ABSTRACT FROM AUTHOR]

Cadmium oxide (CdO) has recently attracted attention as a material with controllable properties tailored for optoelectronic and nanophotonic devices due to its superior mobility. However, its potential application in near-infrared (NIR) remains to be explored. In this work, we demonstrate that the epsilon-near-zero (ENZ) wavelength and nonlinear optical properties of CdO films can be effectively tuned by Mo doping. The results show that Mo doping increases the electron concentration as well as improve the crystalline quality of CdO. With increasing Mo doping, we achieve blueshifts of the ENZ wavelength from 2.89 to 1.56 μm. The nonlinear absorption (NLA) behavior at 1550 nm changes from reverse saturable absorption to saturable absorption with increasing Mo content. Moreover, significant improvement in NLA performance with nonlinear absorption coefficient β = −72 cm/GW is observed at the highest doping content. Our work shows that doped CdO films with tunable optoelectrical and nonlinear optical properties can be an ideal candidate for optoelectronic and nanophotonic application in the NIR region. [ABSTRACT FROM AUTHOR]

Herein, we report the extraction of natural pigment curcumin from curcuma longa and their linear and third-order nonlinear optical (NLO) characteristics. The characterization techniques viz., UV–Visible absorption, FT-IR, Micro Raman and Gas Chromatography Mass Spectrum (GC–MS) are used to study the spectral characteristics of curcumin. Third-order NLO features of curcumin are studied using Z‒scan technique with a semiconductor diode laser working at 405 nm wavelength. The natural pigment exhibits negative nonlinear index of refraction resulting from self-defocusing and positive coefficient of absorption is the consequence of reverse saturable absorption (RSA). The order of nonlinear index of refraction (n2) and nonlinear coefficient of absorption (β) is measured to be 10−7 cm2/W and 10−2 cm/W, respectively. Third-order NLO susceptibility (χ(3)) and second-order hyperpolarizability (γ) of curcumin is measured to be 2.73 × 10‒7 esu and 1.67 × 10‒31 esu, respectively. A low optical limiting (OL) threshold of 0.71 mW is observed in the extracted pigment. The experimental results are supplemented by quantum mechanical calculations of the NLO parameters. The overall result finding is that curcumin extracted from curcuma longa has the potential to be novel optical candidates for photonics and optoelectronics applications. [ABSTRACT FROM AUTHOR]

Knowledge of the optical properties of blood plays important role in medical diagnostics and therapeutic applications in laser medicine. In this paper, we present a very rapid and accurate artificial intelligent approach using Dragonfly Algorithm/Support Vector Machine models to estimate the optical properties of blood, specifically the absorption coefficient, and the scattering coefficient using key parameters such as wavelength (nm), hematocrit percentage (%), and saturation of oxygen (%), in building very highly accurate Dragonfly Algorithm-Support Vector Regression models (DA-SVR). 1000 training and testing sets were selected in the wavelength range of 250-1200 nm and the hematocrit of 0-100%. The performance of the proposed method is characterized by high accuracy indicated in the correlation coefficients (R) of 0.9994 and 0.9957 for absorption and scattering coefficients, respectively. In addition, the root mean squared error values (RMSE) of 0.972 and 2.9193, as well as low mean absolute error values (MAE) of 0.2173 and 0.2423, this result showed a strong match with the experimental data. The models can be used to accurately predict the absorption and scattering coefficients of blood, and provide a reliable reference for future studies on the optical properties of human blood. [ABSTRACT FROM AUTHOR]

In recent years, 2D Cr2S3 has earned lots of attentions in the fields of photocatalysis and photodetector due to its outstanding environmental stability and high responsivity. However, up to now, the optical properties of 2D Cr2S3, especially the NLO properties of Cr2S3 have been rarely studied. In this work, the NLO properties of Cr2S3-nanoparticles in 1 μm have been investigated by using open-aperture (OA) Z-scan method. The nonlinear absorption coefficient (β), modulation depth and saturable intensity are measured to be -2.6 cm/GW, 11.5%, and 0.115 MW/cm2, respectively. Furthermore, by depositing Cr2S3 nanoparticles on a side-polished fiber and inserting into a ytterbium-doped fiber laser (YDFL) cavity, stable mode-locking laser and Q-switching laser with a pulse width of 10.2 ns and 2.95 µs are achieved, respectively. These results demonstrate that Cr2S3 is a promising saturable absorber (SA) for the fiber laser applications. [ABSTRACT FROM AUTHOR]

Physical properties of mantle minerals are essential for comprehensive geodynamic modeling. High-pressure experiments allow measurements of physical properties but fundamental insights into their evolution with pressure are often experimentally inaccessible. Here we report the first in situ experimental determination of the optical refractive index, its wavelength-dispersion, and optical absorption coefficient of ferropericlase up to ~140 GPa at room temperature. All these properties change gradually in dominantly high-spin (below ~50 GPa) and low-spin (above ~80 GPa) ferropericlase. However, in the mixed-spin state (i.e., significant presence of both high- and low-spin iron), the index dispersion and the absorption coefficient decrease by a factor of three and ~30%, respectively. These anomalies suggest that charge transport by small polaron is reduced in mixed-spin ferropericlase, providing fundamental insights into the factor-of-three lower electrical conductivity of ferropericlase at ~50–70 GPa. [ABSTRACT FROM AUTHOR]

Copyright of Momento: Revista de Física is the property of Universidad Nacional de Colombia, Departamento de Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chalcogenide‐based double perovskite materials have recently attracted attention of researchers because of their excellent properties and eco‐friendly nature. These compounds have proven to comprise better oxidation resistance, high‐temperature stability, and lower processing cost. In this report, the first‐principles study on chalcogenides double perovskites Ba2MgXO6 (X = S, Se) is described. It is shown that these perovskites can be synthesized, as they satisfy the structural, dynamical, and thermodynamical stability criteria. It is revealed that these double perovskites are inherently semiconductors in nature with low bandgap values, 0.33 eV for Ba2MgSO6 and 0.66 eV for Ba2MgSeO6 along Γ symmetry point. The absorption coefficient ≈105 cm−1 and the reflectivity below 12% in visible region are calculated. Therefore, the Ba2MgXO6 for solar cell applications is recommended. Also, on the basis of calculated larger values of figure of merit, these perovskites are proposed for thermoelectric applications at high temperatures. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) semiconductors are widely regarded as promising contenders for the next generation of optoelectronics and microelectronics, rendering the development of novel 2D semiconductors a focal point in current research. In this study, our attention is directed towards the non-van der Waals material Cu6GeWS8, where we have successfully predicted a stable 2D monolayer, designated as 2D Cu6GeWS8. This monolayer exhibits a direct bandgap of 1.709 eV, which maintains its robustness under biaxial strain ranging from −4% to 3%. Remarkably, the monolayer Cu6GeWS8 showcases high hole mobility and demonstrates a moderate optical absorption coefficient across the visible and ultraviolet spectra. Notably, our investigation reveals that the monolayer Cu6GeWS8 possesses an exceptionally low lattice thermal conductivity of 0.593 W m−1 K−1 at room temperature. These findings underscore the excellent physical characteristics of the predicted monolayer Cu6GeWS8, positioning it as a promising candidate for advanced low-dimensional devices. [ABSTRACT FROM AUTHOR]

We have explored the electronic and optical properties of the stanene–BeO heterostructure using density functional theory (DFT), including van der Waals interaction using the DFT-D3 correction method of Grimme. The heterostructure exhibits a significant band gap opening, with 93 meV (PBE) and 141 meV (HSE06) values. The impact of spin–orbit coupling (SOC) has also been studied, with PBE + SOC exhibiting a band gap of 55 meV and HSE06 + SOC exhibiting a band gap of 71 meV. Using the DFT-1/2 method, various optical parameters of BeO and Sn monolayer and Sn-BeO heterostructure were studied. The results show a strong red shift in the absorption coefficient, extinction coefficient, and reflectivity, with a prominent absorption peak in the near-UV and visible regions. A significant second harmonic generation peak of 8 × 104 pm V−1 was also obtained. The excellent optical properties of the heterostructure indicate its potential for use in future optoelectronic devices. [ABSTRACT FROM AUTHOR]

The aggregate-to-binders ratio (A/Bs) is an important parameter for the design and preparation of repair mortars. In this paper, the influences of A/Bs on the physical and mechanical properties of red-mud-modified magnesium phosphate repair mortar (RMPM) were systematically investigated. By exploring the capillary absorption characteristics of RMPM, the effect mechanism of A/Bs on its water resistance and mechanical properties was further clarified. The results indicated that the fluidity of fresh RMPM reduced with an increase in A/Bs, and its setting time was first shortened and then prolonged. The compressive strength, flexural strength, interfacial bonding strength, and water resistance of RMPM increased and then decreased with the increasing A/Bs and reached the maximum when the A/Bs was 1.0. The capillary absorption of RMPM was a linear correlation with the square root of the immersion time, and whose slope, that is, the capillary absorption coefficient, and capillary porosity decreased and then increased with the increase in A/Bs. Capillary porosity had a linear relationship with the strength retention rate, which indicated that A/Bs produced a significant effect on the water resistance of RMPM by modifying its capillary pore characteristics. When the A/Bs was 1.0, RMPM had the lowest capillary absorption coefficient and capillary porosity, and thus possesses appropriate mechanical properties and water resistance. [ABSTRACT FROM AUTHOR]

The construction industry's quest for sustainable materials drives the investigation into novel additives to enhance clay brick performance. High-Density Polyethylene (HDPE) and Polyethylene Terephthalate (PET) polymers hold promise, yet their impact on porosity and water absorption in varying grain sizes remains underexplored. They incorporated HDPE and PET polymers in diverse proportions and grain sizes into unfired clay bricks, examining the resulting changes in porosity and water absorption through bulk density measurements, microscopy, and capillary water absorption coefficient analysis. Polymer additives, particularly d=1 mm PET, significantly reduce porosity, enhancing brick performance. The capillary water absorption coefficient establishes a direct link between polymer content and increased porosity. As polymer proportions rise, so does brick porosity, offering a nuanced understanding of the relationship. SEM analysis highlights PET mortar's consistent, lowporosity structure, underscoring the potential for sustainable construction materials. This study provides crucial insights for future developments in eco-friendly construction practices. In summary, the integration of HDPE and PET polymers presents a promising avenue for advancing sustainable construction materials, offering a balance between enhanced performance and environmental considerations. [ABSTRACT FROM AUTHOR]

This work investigates the inverse coupled radiation–conduction problem for estimating thermophysical parameters and source terms by an improved grey wolf optimization (GWO). The transient coupled radiation–conduction heat transfer problem in participating slab media is solved by the finite volume method. The radiative intensities on both boundaries are adopted as known measurement information in the inverse model. To overcome the disadvantages of the original GWO algorithm, an improved grey wolf algorithm (IGWO) is developed by introducing the weight strategy and nonlinear factors. Three benchmark functions are adopted to prove that the IGWO has a faster convergence speed and higher estimation accuracy than the original one. The IGWO is applied to inverse the thermophysical parameters and source terms based on the coupled radiation–conduction model; the results indicate that the IGWO is accurate and effective for estimating refractive index, absorption coefficient, and source terms. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have recently drawn interest in various applications due to their superior electronic properties, high specific surface area, and surface activity. However, studies on the catalytic properties of the 2D counterpart of V2O5 are scarce. In the present study, the catalytic properties of 2D V2O5 vis-à-vis bulk V2O5 for the degradation of methylene blue dye are discussed for the first time. The 2D V2O5 catalyst was synthesized using a modified chemical exfoliation technique. A massive increase in the electrochemically active surface area of 2D V2O5 by one order of magnitude greater than that of bulk V2O5 was observed in this study. Simultaneously, ~ 7 times increase in the optical absorption coefficient of 2D V2O5 significantly increases the number of photogenerated electrons involved in the catalytic performance. In addition, the surface activity of the 2D V2O5 catalyst is enhanced by generating surface oxygen vacancy defects. In the current study, we have achieved ~ 99% degradation of 16 ppm dye using the 2D V2O5 nanosheet catalysts under UV light exposure with a remarkable degradation rate constant of 2.31 min−1, which is an increase of the order of 102 from previous studies using V2O5 nanostructures and nanocomposites as catalysts. Since the enhanced photocatalytic activity emerged from the surface and optical properties of the catalyst, the current study shows great promise for the future application of 2D V2O5 in photo- and electrocatalysis. [ABSTRACT FROM AUTHOR]

Metal halide perovskites (MHPs) are considered as promising candidates in the application of nonvolatile high‐density, low‐cost resistive switching (RS) memories and artificial synapses, resulting from their excellent electronic and optoelectronic properties including large light absorption coefficient, fast ion migration, long carrier diffusion length, low trap density, high defect tolerance. Among MHPs, 2D halide perovskites have exotic layered structure and great environment stability as compared with 3D counterparts. Herein, recent advances of 2D MHPs for the RS memories and artificial synapses realms are comprehensively summarized and discussed, as well as the layered structure properties and the related physical mechanisms are presented. Furthermore, the current issues and developing roadmap for the next‐generation 2D MHPs RS memories and artificial synapse are elucidated. [ABSTRACT FROM AUTHOR]

Lead sulfide colloid quantum dots (PbS QDs) offer great opportunities to revolutionize large‐area short‐wave infrared (SWIR) detection technologies due to high absorption coefficients and spectral selectivity. However, a critical issue for QDs‐based SWIR detectors is high dark current noise due to thermal carriers and the large amounts of surface defect states induced by the ligand exchange process, which hinders the improvement of the room temperature detectivity and linear dynamic range. Herein, it is demonstrated that these dilemmas can be overcome by adopting a novel hybrid‐layered phototransistor device architecture composed of a self‐assembly high‐mobility organic conduction channel and a bulk heterojunction infrared absorber containing PbS QDs as sensitizers. Strong photo absorption in the photoactive layer creates photogenerated charges that are transferred to the conduction channel, where they recirculate many times due to the long trapped‐electron lifetime in the photoactive layer and the high carrier mobility of the channel. Therefore, low dark current noise and high photoconductive gain are achieved by both electrical gating and photodoping for carrier‐density modulation of phototransistors. Finally, an optimized SWIR phototransistor device with a low room‐temperature dark current of 7 pA and a high detectivity of 8 × 1012 Jones under 1650 nm light illumination is demonstrated. [ABSTRACT FROM AUTHOR]