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Purpose: To evaluate the reliability of various reference areas for digital alignment between 3D resting and smiling facial models. Materials and Methods: 3D posed and natural smiling faces of 33 adults were registered to the respective neutral faces, using six matching strategies with different reference matching surfaces: nose (N), nose + central forehead (NFc), nose + whole forehead (NFw), nose + chin (NC), nose + central forehead + chin (NFcC), and nose + whole forehead + chin (NFwC). The positional discrepancies of the registered images were measured at the left and right pupil centers. Results: Two-way ANOVA and post hoc multiple pairwise t test with Bonferroni correction (α = .05) were used to evaluate the measurements. As a result, the use of larger reference areas increases the trueness of image-matching, whereas there was no statistically significant difference between the matching strategies within the same smiling type. Meanwhile, the image registration of posed smiles resulted in fewer positional disparities than the natural smiles with significant differences observed for the registration using the NC and NFcC surface-based matching areas at the right pupil (P = .030 and .026, respectively). Conclusions: The findings of this study suggest that the reference surface areas and smiling types have some impact on the accuracy of 3D smiling facial image alignments. Large and evenly distributed matching surfaces are recommended for posed smiles, whereas caution should be taken when using the chin area as a reference surface for matching natural smile facial images. [ABSTRACT FROM AUTHOR]

Exposure to ambient air contaminates the surface of graphene sheets. Contamination may arise from different sources, and its nature alters the frictional behavior of the material. These changes in friction enable the observation of the early stages of contaminants' adsorption in graphene. Using a friction force microscope, we show that molecular adsorption initiates at the edges and mechanical defects in the monolayer. Once the monolayer is covered, the contaminants spread over the additional graphene layers. With this method, we estimate the contamination kinetics. In monolayer graphene, the surface area covered with adsorbed molecules increases with time of air exposure at a rate of 10−14 m2/s, while in bilayer graphene, it is one order of magnitude smaller. Finally, as the contaminants cover the additional graphene layers, friction no longer has a difference concerning the number of graphene layers. [ABSTRACT FROM AUTHOR]

Coagulational growth in an aerosol is a multistep process; first particles collide, and then they coalesce with one another. Coalescence kinetics have been investigated in numerous prior studies, largely through atomistic simulations of nanoclusters (102–104 atoms). However, with a few exceptions, they have either assumed the process is completely isothermal or is a constant energy process. During coalescence, there is the formation of new bonds, decreasing potential energy, and correspondingly increasing internal kinetic (thermal) energy. Internal kinetic energy evolution is dependent not only on coalescence kinetics but also on heat transfer to the surrounding gas. Here, we develop and test a model of internal kinetic energy evolution in collisionally formed nanoclusters in the presence of a background gas. We find that internal kinetic energy dynamics hinge upon a power law relationship describing latent-to-sensible heat release as well as a modified thermal accommodation coefficient. The model is tested against atomistic models of 1.5–3.0 nm embedded-atom gold nanocluster sintering in argon and helium environments. The model results are in excellent agreement with the simulation results for all tested conditions. Results show that nanocluster effective temperatures can increase by hundreds of Kelvin due to coalescence, but that the rise and re-equilibration of the internal kinetic energy is strongly dependent on the background gas environment. Interestingly, internal kinetic energy change kinetics are also found to be distinct from surface area change kinetics, suggesting that modeling coalescence heat release solely due to surface area change is inaccurate. [ABSTRACT FROM AUTHOR]

The power-law fluid flow in tree-like self-similar branching networks is prevalent throughout the natural world and also finds numerous applications in technology such as oil recovery and microfluidic devices. We investigate analysis of optimal power-law fluid flow conditions and the optimal structures within tree-like branching networks, focusing on maximizing flow conductance under the constraint of the network tube's volume and the surface area. The study considered fully developed laminar power-law fluid flow regimes without considering any losses in the network system. A key observation was the sensitivity of the dimensionless effective flow conductance to the network's geometrical parameters. We found that the maximum flow conductance occurs when a dimensionless radius ratio β ∗ satisfies the equation β ∗ = N − 1 / 3 and β ∗ = N − (n + 1) / (3 n + 2) under constrained tube-volume and surface-area, respectively. Here, N represents the bifurcation number of branches splitting at each junction, and n is the fluid power-law index. We further find that this optimal condition occurs when pressure drops are equipartition across each branching level. We validated our results with various experimental results and theories under limiting conditions. Further, Hess–Murray's law is justified and extended for the shear-thinning and shear-thickening fluid flows for an arbitrary number of branches N. Further, in this study, we also derive the relationships between the geometrical and flow characteristics of the parent and daughter tubes as well as the generalized scaling laws at the optimal conditions for the other essential parameters such as tube-wall stresses, length ratios, mean velocities, tube-volume, and surface-area of the tube distributing within the networks. We find that the fluid power-law index n does not influence the constrained tube-volume scaling at the optimal conditions; however, the scaling laws vary with n under the constrained tube's surface area. These findings offer valuable design principles for developing efficient transport and flow systems. [ABSTRACT FROM AUTHOR]

Pyrogenic silica is a form of amorphous silica with a high surface area and a heterogeneous distribution of silanol hydroxyl terminations and defects. In this work, the interesting and unusual form of the hydroxyl-stretch 2D-IR spectrum of pyrogenic silica is presented and explored in the deuterated (deuteroxyl) form. Transition dipole couplings between hydrogen-bonded and non-hydrogen-bonded silanol groups give a distinct cross-peak in the 2D-IR spectrum, displaying interstate coherence oscillations during the 2D-IR experimental waiting time. The strong asymmetry about the diagonal is proposed to be the result of both the relatively small transition dipole coupling strength and the extreme differences in the width of the hydrogen-bonded and non-hydrogen-bonded silanol bands. The resulting interference of negative and positive cross-peaks has minimal intensity in the below-diagonal ω3 < ω1 region of the spectrum. An additional strong positive cross-peak is observed at a position in the 2D-IR spectrum inconsistent with transition dipole coupling. An assignment as a fifth order effect is proposed. [ABSTRACT FROM AUTHOR]

We present results of resonant ultrasound spectroscopy (RUS) measurements applied to granular high explosive materials at different bulk pressing densities and degree of thermal conditioning. The material chosen in this study is a ubiquitously used explosive material known as pentaerythritol tetranitrate (PETN), which is used commercially in civil and defense applications both as a binderized plastic bonded explosive material and an unbinderized neat material. However, changes in granular PETN bulk elastic properties due to thermal conditioning, which could have implications for better understanding environmental aging-related effects, have not been well studied even though it is believed that elasticity may play an important role in explosive material initiation mechanisms. Furthermore, monitoring elastic property changes in granular explosive pressings has not yet been demonstrated using RUS, which is an appealing non-destructive characterization tool that requires only dry point contact with the explosive material. To this end, we report the first study using RUS to quantify the elastic properties of binderized and neat PETN pressings as well as to quantify changes in elastic properties as a function of both thermal conditioning and bulk pressing density. Elastic stiffness coefficients, sometimes more commonly referred to as elastic constants, calculated from the RUS measurements on the different PETN-based materials show a significant increase for the post-conditioned samples compared to the pre-conditioned samples. This trend of increasing elastic properties with thermal conditioning was consistent for different density pressings, different thermal exposure conditions, and even different neat PETN pressings of differing average crystal sizes and/or specific surface areas. [ABSTRACT FROM AUTHOR]

In this paper, polarization-stable and spectrally single-mode operation of oxide-confined multi-junction vertical-cavity surface-emitting lasers (VCSELs) are achieved by using a non-circular integrated anti-phase transverse mode filter. A record-high single-mode output power is obtained by radially reducing effective mirror reflectivity at the surface areas where the higher order modes are expected to lase, leading to an increase in the threshold gain for these transverse modes, all the while minimal losses are introduced to the fundamental mode. The polarization control of such devices is achieved by using a non-circular mode filter in order to perturb the cylindrical symmetry of the cavity. An elliptically etched surface relief is shown to be effective in realizing a single-mode single-polarization device over a wide range of operating bias currents and temperatures. The continuous-wave light–current–voltage characteristics of 8-junction 940 nm VCSELs show single-mode output power >13 mW at room temperature, spectrally measured with a side-mode suppression ratio of >30 dB. This single-mode performance can be achieved depending on the ratio between the relief opening and the oxide aperture size. Additionally, the single-polarization behavior of such devices (with an extinction ratio of >15 dB) is shown to be dependent on the orientation of the elliptical mode filter, where the light is mainly polarized along the minor axis of the elliptical feature. Overall, combined with a multi-junction active region, the elliptical model filter is able to achieve highly efficient single-mode linearly polarized VCSELs. [ABSTRACT FROM AUTHOR]

ZnO nanostructures with various aspect ratios have been synthesized for H 2 gas detection applications. The thermal-decomposition method was employed at different annealing temperatures (350, 450, and 550 °C) and its impact on various shapes/sizes of ZnO nanostructures is demonstrated. Thermal decomposition performed at 350 °C exhibited a maximum (∼6.25) aspect ratio among them. Its capability of H 2 sensing was also observed to be maximum by realizing ∼483% of sensor response at 180 °C under H 2 gas concentration of 80 ppm. The sensor response is ∼3 times (∼177%) and ∼9 times (∼53%) higher at ZnO nanostructure synthesized at 350 °C than at 450 °C, and 550 °C, respectively. The higher sensor response has been attributed to the increased availability of active surface area for adsorption/desorption of gas molecules. ZnO@350 nanostructure showed significantly higher selectivity towards H 2 gas than other target chemical inputs. We have also studied H 2 -induced metallization on the surface of ZnO nanostructures which plays an important role for improving the selectivity and sensor response. This study provides insight into the role of aspect-ratio-controlled shape/sized ZnO in improving H 2 gas sensing. [Display omitted] • Aspect-ratio-controlled ZnO nanostructures for H 2 gas sensing was examined. • The maximum sensor response (∼483%) for ∼6.25 aspect ratio ZnO was observed. • ZnO-nanorods pose higher active surface area than NPs that reduced operating temperature. • The sensor response is ∼3 times and ∼9 times higher at 350 °C than at 450 °C, and 550 °C. • H 2 -induced metallization on ZnO surface significantly improved the sensor selectivity. [ABSTRACT FROM AUTHOR]

Ultrathin nanosheets possess a distinctive structure characterized by an abundance of active sites fully accessible on their surface. Concurrently, their nanoscale thickness confers an extraordinarily high specific surface area and promising electronic properties. To date, numerous strategies have been devised for synthesizing precious metal nanosheets that exhibit excellent electrocatalytic performance. In this paper, recent progress in the controlled synthesis of two-dimensional, ultrathin nanosheets by a self-assembly mechanism using functional surfactants is reviewed. The aim is to highlight the key role of functional surfactants in the assembly and synthesis of two-dimensional ultrathin nanosheets, as well as to discuss in depth how to enhance their electrochemical properties, thereby expanding their potential applications in catalysis. We provide a detailed exploration of the mechanisms employed by several long-carbon chain surfactants commonly used in the synthesis of nanosheets. These surfactants exhibit robust electrostatic and hydrophobic effects, effectively confining the crystalline growth of metals along lamellar micelles. Moreover, we present an overview of the electrocatalytic performance demonstrated by the ultrathin nanosheets synthesized through this innovative pathway. Furthermore, it offers valuable insights that may pave the way for further exploration of more functional long-chain surfactants, leading to the synthesis of ultrathin nanosheets with significantly enhanced electrocatalytic performance. [ABSTRACT FROM AUTHOR]

To overcome the disadvantages of poor intrinsic conductivity and stability of ZnCo2O4, a ZnCo2O4@MnMoO4 composite as an emerging pseudocapacitor electrode material with high specific capacitance, environmental friendliness, morphological diversity, and unique hierarchical structure was synthesized via a simple two-step hydrothermal method. The research results indicate that the ZnCo2O4@MnMoO4 composite can present a high specific capacity of 1628 F g-1 at a current density of 1 A g-1 and good cycling stability with 69% capacity retention after 10 000 cycles at 10 A g-1. Hybrid supercapacitors (HSCs) assembled with the ZnCo2O4@MnMoO4 cathode and activated carbon anode can deliver an energy density of 48 W h kg-1 at a power density of 695 W kg-1, and their capacity retention reached 61% after 8000 charge-discharge cycles at a current density of 10 A g-1. This could be attributed to the synergistic effect of the specific surface area and electrical conductivity enhanced by compositing ZnCo2O4 with MnMoO4. As a result, the excellent electrochemical properties show that the ZnCo2O4@MnMoO4 composite has strong application potential for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

This study explores the impact of organic cations in bismuth iodide complexes on their memristive behavior in metal-insulator-metal (MIM) type thin-layer devices. The presence of electron-donating and electron withdrawing functional groups (-CN, -CH3, -NH2, and -N(CH3)2) on pyridinium cations induces morphological alterations in crystals, thus influencing the electronic or ionic conductivity of devices comprising sandwiched thin layers (thickness = 200 nm ± 50) between glass/ITO as bottom electrode (~110 nm) and copper (~80 nm) as the top electrode. It was found that the current-voltage (I-V) scans of the devices reveal characteristic pinched hysteresis loops, a distinct signature of memristors. The working voltage windows are significantly influenced by both the types of cation and the dimensionality of ionic fragments (0D or 1D) in the solid-state form. Additionally, the temperature alters the surface area of the I-V loops by affecting resistive switching mechanisms, corresponding log-log plots at three temperatures (-30 °C, room temperature and 150 °C) are fully studied. Given that a memristor can operate as a single synapse without the need for programming, aligning with the requirements of neuromorphic computing, the study investigates long-term depression, potentiation, and spike-time-dependent plasticity-a specific form of the Hebbian learning rule-to mimic biologically synaptic plasticity. Different polar pulses, such as triangle, sawtooth, and square waveforms were employed to generate Hebbian learning rules. The research demonstrates how the shape of the applied pulse series, achieved by overlapping pre- and postpulses at different time scales, in association with the composition and dimensionality of ionic fragments, lead to changes in the synaptic weight percentages of the devices. [ABSTRACT FROM AUTHOR]

Composite materials based on Nb2O5 nanoparticles dispersed over activated carbon (Nb/AC) obtained from PET waste were used as catalysts for wastewater treatment. These composites were synthesized by mechanical mixing of AC and commercial Nb2O5, followed by H2O2 treatment. The methylene blue dye (MB) was used as a model contaminant and the fungicide prothioconazole (PCZ) was the target molecule. Contaminant removal from water occurred mainly via adsorption by AC and via a combined process of adsorption/oxidation in the case of Nb/AC composites. The increase in the Nb amount in the catalysts reduced the BET surface area but increased the reaction rates due to the oxidation properties of Nb2O5. The reaction mechanism is Mars–Van Krevelen-like, driven by the peroxo groups (active sites) on the Nb2O5 surface. Moreover, the Nb/AC composites were highly efficient catalysts for PCZ oxidation and its main metabolite (prothioconazole-desthio) from water. [ABSTRACT FROM AUTHOR]

The high specific surface area of graphene is an important factor to enable a large molecular adsorption on the surface, thus enabling direct sensing on a versatile surface. A large area graphene sensor (1 cm2) is fabricated using a transfer method for the detection of ammonia (NH3) gas under ambient conditions. The ambient atmosphere contains 21% oxygen (O2), and thus it is crucial to understand its impact on the sensing of ammonia gas. The sensing response is analyzed under both the inert nitrogen (N2) gas and condensed dry air (CDA) containing 78.08% N2, 20.95% of O2, and 0.93% of argon gas. Upon interaction with the graphene, both NH3 and O2 resulted in opposite electrical responses. Thus, this finding reveals a polarity dependent interaction of gases with the graphene. [ABSTRACT FROM AUTHOR]

This study introduces a novel polyoxometalate (POM) heterostructure designed to address challenges in ultratrace analysis and sensor stability. Supercritical anti‐solvent and hydrothermal methods are employed to fabricate a composite that enhances stability, sensitivity, and selectivity for cysteine (Cys) detection. The optimization of inter‐component interactions and improved dispersibility contributes to superior stability and longevity. These preparation techniques increase the total oxygen vacancy density, which facilitates the migration of surface oxygen vacancies and promotes the electrocatalytic process. Additionally, tuning the band structure effectively suppresses electron–hole recombination, thereby enhancing catalytic capability. The integration of potassium phosphotungstate (KPW) as an electron transport mediator results in a stable “point‐surface” loading structure, increasing active sites and improving the material's specific surface area and catalytic efficiency. The Cu/Zr nanoparticle‐grafted KPW composite (CZPW) demonstrates excellent performance, achieving an ultratrace detection limit of 30.6 pM and a broad linear detection range from 50 pM to 1 mM. Overall, this study elucidates the mechanisms of supercritical preparation and its impact on electrocatalytic Cys reactions, providing valuable insights into the development of highly effective and stable biosensors. [ABSTRACT FROM AUTHOR]

The present investigation was aimed at predicting a still (i.e., dead) vs. live embryo within a hatching goose egg by measuring the eggshell cooling rate. For this, we daily measured the temperature (T) values on the shell surface of goose eggs after they were removed from the incubator and during further natural cooling. T was recorded every 0.5 h for further 1.5 h of cooling. It was possible to recognize eggs with dead embryos using the combination of T , egg weight (W), and surface area (S). The resultant indicator (TS / W) was called specific temperature index (STI). The mathematical relationship using STI measurements between Days 8–13 facilitated 80 % correct identification of the eggs with dead embryos. Additionally, we derived mathematical dependencies for shell weight (W s) and thickness (t) by utilizing the values of W , egg volume (V), S , the average T of all measurements taken, as well as the drop in T during 1.5 h of natural cooling. The key advantage of these parameters was their measurement and/or calculation by applying non-destructive methods. The integrated application of these parameters resulted in achieving high calculation accuracy as judged by correlation coefficients of 0.908 for W s and 0.593 for t. These novel mathematical models have the potential to decrease hatching waste by predicting embryo viability. Our research will add to a toolkit for non-invasive egg assessment that is useful in the poultry industry, research on eggs, and engineering. [Display omitted] • We aimed at predicting still (dead) vs. live embryos in goose eggs by cooling rate. • We measured shell surface temperature (T) during natural cooling for 1.5 h. • Specific temperature index was derived to predict correct identification of eggs. • We propose this index to predict eggs with dead embryos and reduce hatching waste. [ABSTRACT FROM AUTHOR]

Direct Ink Writing has been demonstrated to be a promising route to produce ceramic catalysts with complex geometries and enhanced catalytic performances. To increase the catalytic performances, chemical etching can be conducted to get an interconnected and hierarchical porous structure, to increase the surface area and the contact time of the reactants. In this work, DIW alpha (α)-Al 2 O 3 catalysts were chemically etched with hydrofluoric acid (HF). Several combinations of acid concentrations and etching times were studied to find the optimal etching condition. For HF concentration of 5, 20 and 40 wt%, the optimal etching time was 48, 24 and 5 h, respectively, being 40 wt% the concentration that shows the greatest increase of surface porosity (of around 5%). HF etching can produce an interconnected porosity on 3DP α-Al 2 O 3 , but it does not yield improvement in catalytic performances when the content of fluor (F) is higher than 10 at% since it produces parasite reactions. [ABSTRACT FROM AUTHOR]

The accurate detection of hazardous gases and monitoring of ambient temperature are crucial for preserving the ecological environment, safeguarding human health, and fostering industrial advancement. In this research, a straightforward hydrothermal technique was employed to synthesize the heterogeneous nanocomposite structure of CsPbBr 3 /SnWO 4 , which facilitates the detection of ethanolamine gas at room temperature. The synthesized CsPbBr 3 /SnWO 4 heterostructures underwent further analysis using XRD, SEM, HRTEM, XPS, BET and Mott-Schottky techniques. The findings revealed that the CsPbBr 3 /SnWO 4 heterostructure exhibits a coarse cubic morphology, consisting of nano-cubic CsPbBr 3 and nano-sheet SnWO 4. Additionally, the integration of CsPbBr 3 markedly enhances the specific surface area of the pristine SnWO 4 nanosheets. Due to its coarse surface, expansive contact area, and n-n heterojunction, CsPbBr 3 –SnWO 4 demonstrates remarkable selectivity, superior long-term stability, and a sensitivity of 45.6 to ethanolamine at ambient temperature. In conclusion, the CsPbBr 3 /SnWO 4 heterostructure, constructed from a cube with a rough surface, is anticipated to serve as an effective room temperature sensor with heightened selectivity for ethanolamine. [ABSTRACT FROM AUTHOR]

Well-dispersed MIL-100(Fe) nanoparticles were synthesized under mild conditions and used to construct a photo-Fenton system (VMH system) with the assistance of visible-light irradiation and hydrogen peroxide. In such a VMH system, the MIL-100(Fe) has a high specific surface area and provides numerous Fe3+ active sites, thus accelerating the reaction of Fe3+ with photo-generated electrons under visible-light irradiation and generates Fe2+, and then the acquired Fe2+ can activate H2O2 to generate ⋅OH, accompanying with the oxidation of Fe2+ to Fe3+. Hence, the in-situ recycling of Fe2+/Fe3+ promotes the generation of ·OH, thus making the VMH system exhibits promising photocatalytic activity. The removal rate of ciprofloxacin in the VMH system is as high as 95.2% within 120 min photo-Fenton reaction, which is about 26 times higher than that of the Visible light/MIL-100(Fe) system. Moreover, the VMH system also exhibits strong degradation ability to other typical antibiotics, such as tetracycline, norfloxacin and cephalexin, and maintains high cyclic stability, revealing great practical application potential in the purification of antibiotic wastewater. [ABSTRACT FROM AUTHOR]

Herein, three g-C3N4(MCN/TCN/UCN), obtained by the direct pyrolysis of melamine/urea/thiourea respectively, were introduced as supports to optimize the NH3-SCR activity of Ce-W-Ti catalyst. Compared to CWT-400-Air, CWT@g-C3N4(2)-300-N2 exhibits lower crystalline anatase TiO2 and larger specific surface area, which improves the dispersion of Ce/W/Ti species on catalysts surface. Furthermore, the introduction of g-C3N4 as supports also contributes to doping C/N elements into Ce-W-Ti catalyst and increases the Ce3+/(Ce3++Ce4+) and Oα/(Oα+Oβ) molar ratios on catalyst surface. These all are advantageous to the NH3-SCR activity. However, UCN shows better promotional effect than MCN and TCN. This might be mainly attributed to the loose and porous stacked layered fold structure of UCN, the larger BET surface area, higher dispersion of Ce/W/Ti species and moderate weak/medium-strong acid sites of CWT@UCN(2)-300-N2. At the same time, the influence of carbon nitride amount, calcination atmosphere and calcination temperature on the NH3-SCR activity of CWT@g-C3N4 catalyst were also investigated. [ABSTRACT FROM AUTHOR]

In this study, cost-effective alkali-activated materials made from industrial side streams (blast furnace slag and Na-jarosite) were developed for catalytic applications. The catalytic activity of the prepared materials was examined in catalytic wet peroxide oxidation reactions of a bisphenol A in an aqueous solution. All materials prepared revealed porous structure and characterisation expressed the incorporation of iron to the material via ion exchange in the preparation step. Furthermore, the materials prepared exhibited high specific surface areas (over 200 m2/g) and were mainly mesoporous. Moderate bisphenol A removal percentages (35%–37%) were achieved with the prepared materials during 3 h of oxidation at pH 7–8 and 50°C. Moreover, the activity of catalysts remained after four consecutive cycles (between the cycles the catalysts were regenerated) and the specific surface areas decreased only slightly and no changes in the phase structures were observed. Thus, the prepared blast furnace slag and Na-jarosite-based catalysts exhibited high mechanical stability and showed good potential in the removal of bisphenol A from wastewater through catalytic wet peroxide oxidation. [ABSTRACT FROM AUTHOR]

In this work, the content of lignin, pitch, and PAN as well as the preparation process would be systematically controlled in order to prepare carbon nanofibers (CNFs) with cross‐linked structure, high specific surface area, and good flexibility. The evolution of nanofibers with different lignin contents during stabilization and carbonization were explored, and the properties of the resultant CNFs as supercapacitor self‐supported electrodes were compared. The results indicated that with the increase of lignin content, not only cross‐linked structures were introduced in CNFs, but also the flexibility were obviously improved, accomplishing for supercapacitor self‐supported electrodes. Moreover, CNFs with different content of lignin varied in fiber morphology and microstructure, harvesting developed porous structure in CNFs. PPL3‐CNF prepared with adding lignin at a mass ratio of 3/7 into a concentration of 10 wt.% pitch/PAN solution presented the highest specific surface area of 949 m2 g−1, exhibiting an excellent specific capacitance of 190.7 F g−1 at 0.2 A g−1. [ABSTRACT FROM AUTHOR]

This paper introduces a novel wearable flexible gas sensor designed specifically for the detection of d‐limonene. The sensor utilizes materials recognized for their high efficiency‐to‐cost ratio, notably polyaniline (PANI) combined with carboxylated multiwalled carbon nanotubes (MWCNT) and graphene oxide (GO) as sensing layers. The study conducts a comprehensive analysis of the nanocomposite layers, examining their functional groups, morphology, topography, thickness, crystallinity, thermal behavior, surface area, as well as the size and volume of their pores. This examination showed distinctions among the nanocomposite layers. PANI/GO exhibited larger pore size and thickness, while PANI/MWCNT_COOH demonstrated a higher surface area. The analysis of thermal stability demonstrated that the film employing the DBSA dopant exhibited the lowest stability. Morphological characterizations showed a globular structure for PANI, tubular characteristics for PANI/MWCNT_COOH, and a flat nature for PANI/GO. When detecting d‐limonene, nanocomposite films doped with HCl demonstrated notably superior response levels. The gas sensors exhibited high sensitivity (>2.24 mV/ppm), a narrow range for the limit of detection (0.12–0.52 ppm), and excellent reversibility, stability, and selectivity. These findings suggest the possibility of broadening the application of gas sensors to monitor additional volatile compounds, with a particular emphasis on the online monitoring of agricultural products. [ABSTRACT FROM AUTHOR]

Phosphorus (P) and potassium (K) affect seedling growth, root configuration, and nutrient uptake in hydroponic rice, but there are few studies on all growth stages of rice. The purpose of this experiment was to determine the response characteristics of root morphology, plant physiology, and P and K uptake and utilization efficiency to different supplies of P and K. Two local conventional rice varieties (Shennong 265 and Liaojing 294) were used as experimental materials across four treatments, including HPHK (sufficient P and K supply), HPLK (sufficient P supply under low K levels), LPHK (sufficient K supply under low P levels) and LPLK (low P and K levels) in a hydroponic setting. The results showed that HPHK and HPLK significantly decreased the acid phosphatase activity of leaves and roots from full heading to filling stages when compared to LPHK and LPLK. Sufficient supply of P or K significantly increased the accumulation of P and K (aboveground, leaves, stem sheath, and whole plant) and root morphological parameters (root length, root surface area, total root volume, and tips) during major growth stages when compared to LP or LK levels. HPHK was significantly higher than other treatments in terms of dry weight and the root activity at the main growth stage, P and K uptake rates in nutrient solutions at various stages, related P and K efficiency at the maturity stage, yield, effective panicle number, and grain number per panicle. In addition, the effect of HPHK on the above indexes were significantly greater than those of single sufficient supply of P or K. In conclusion, HPHK can improve plant configuration, increase plant P and K absorption and root activity, and increase rice yield and related P and K utilization efficiency. [ABSTRACT FROM AUTHOR]

Green mining is the basic background of high-quality mining, and source reduction is the most important part, among which the optimization of working face height and length is the most active. How to control the working face parameters, reasonably evaluate the surface subsidence characteristics of the super-long working face, and identify the limit working face length and the surface discontinuous deformation threshold is particularly important. In order to solve the problem of irreversible damage to the surface caused by the mining process of the working face, this paper discusses the whole process of surface movement in the 8.8 m super-large mining height working face of Shangwan Coal Mine through field investigation, the maximum subsidence is 6.20 m, with a subsidence coefficient of 0.72. Combined with the inflection point trajectory, advancing degree and subsidence coefficient, the 0.9 coefficient of the working face subsidence basin boundary and the loss reduction strategy far from the limit working face threshold are proposed. The results show that the subsidence basin of 12,401 working face accounts for 34%, the continuous deformation area of surface accounts for 64%, and the influence area of discontinuous deformation area is within 10 times of mining height. With the help of borehole detection verification, the caving zone height within the coal seam overburden to be between 33.2 and 33.25 m and the fracture zone height between 118.08 and 132.83 m. Therefore, the caving ratio is about 3.8, and the fracture ratio is about 13–15, which provides a strong basis for the optimization design of working face and the timing of surface ecological management. [ABSTRACT FROM AUTHOR]

Highlights Processing parameters during the laser‐radiated in‐situ manufacturing process change the thermal history of the thermoplastic composite, which affects porosity and fiber‐resin interfacial bonding quality, and hence the wedge peel strength of the laminate. The effect of different laser powers and consolidation forces on the wedge peel strength of the specimens was investigated. Due to the fiber‐rich area on the tape surface during the laser heating phase as well as the insufficient consolidation force and consolidation length during the consolidation phase, the wedge peel strength decreased due to increased porosity and weak fiber‐resin bonding at the interlayer bonding interface. A conformable consolidation roller of lower hardness was used to improve the wedge peel strength of the laminates, which reduced the initial temperature of the cooling phase, thus inhibiting the void rebound and increasing the bonding strength at the fiber‐resin interface. The cross‐section and peeling surface were characterized by optical microscope and scanning electron microscope. The wedge peel strength of the laminates, with reduced voids and increased interfacial bonding strength between the fibers and the resin, is improved. Mechanism of void formation and evolution in different phases of laser‐radiated in‐situ consolidated laminate. Effect of consolidation roller hardness and deformation on wedge peel strength. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g‐C3N4) has witnessed tremendous research interest due to its narrow bandgap, intrinsic 2D structure, and abundant raw materials. Although g‐C3N4 has some shortcomings such as low specific surface area, poor conductivity and rapid charge carries recombination, various modification methods are constantly emerging to enhance its potential application value in photocatalysis. Increasing the crystallinity of g‐C3N4 is an effective strategy to improve the in‐plane charge separation efficiency. However, it is also reported that amorphous g‐C3N4 possesses a higher adsorption and activation ability over reactants due to its richer surface functional groups than crystalline g‐C3N4. Which type of g‐C3N4 more suits photocatalysis, and which modification method is more suitable for boosting the activity of two types of g‐C3N4, respectively? Based on these issues, the recent advances in the preparation and properties of amorphous and crystalline g‐C3N4 are summarized, and their performance improvement strategies are overviewed thoroughly. Upon systematic comparison and analysis, which modification strategy is more suitable for the two types of g‐C3N4, respectively, is proposed. Their applications are also summed up especially in environment remediation and energy conversation. Finally, the ongoing opportunities and future challenges for amorphous and crystalline g‐C3N4 in the photocatalysis territory are taken for consideration. [ABSTRACT FROM AUTHOR]

The NiCoFe-based alloys are potential high-performing bifunctional electrocatalysts towards overall alkaline water splitting, though it is still challenging to achieve this goal. Herein, the NiCoFe/CeO 2-x heterostructure with abundant interfacial oxygen vacancies is constructed through in - situ hydrogenation. The strong metal-support interaction favors the formation of the medium-entropy NiCoFe ternary alloy and the interfacial oxygen vacancies, while the introduction of the cobalt highly increases the electrochemically active surface area (ECSA). The ECSA of the NiCoFe/CeO 2-x is more than 3 times those of the NiCoFe, NiFe/CeO 2-x , NiCo/CeO 2-x and CoFe/CeO 2-x. Therefore, the NiCoFe/CeO 2-x shows high catalytic performance towards both hydrogen evolution reaction and oxygen evolution reaction with a small overpotential of 42 and 238 mV at 10 mA cm−2 in 1 M KOH, respectively. More importantly, the NiCoFe/CeO 2-x heterostructure with optimal elemental composition demonstrates excellent catalytic performance towards overall water splitting, exhibiting a small cell voltage of 1.52 V at 10 mA cm−2 without i R compensation. In addition, it shows good working stability in the overall water splitting at 100 mA cm−2 during a period of >10 h. • The strong metal-support interaction favors the NiCoFe ternary alloy formation. • The NiCoFe/CeO 2-x possesses abundant interfacial oxygen vacancies. • The introduction of Co greatly enhances the electrochemically active surface area. • The NiCoFe/CeO 2-x is highly active towards both hydrogen and oxygen evolution. • The high activity is due to the synergistic effect between NiCoFe and CeO 2-x. [ABSTRACT FROM AUTHOR]

The booming development of mobile devices has remarkably improved the lives of people, but it also leads to severe electromagnetic radiation problems. Therefore, it has become significantly important to develop electromagnetic interference (EMI) shielding materials for electromagnetic protection. In recent years, MXenes have attracted much attention in the field of EMI shielding, owing to outstanding electrical conductivity, high specific surface area and hydrophilicity. Firstly, this review introduces EMI shielding mechanism and categorization of EMI shielding materials. Subsequently, the research progress of MXenes/polymer‐based EMI shielding materials is reviewed in detail, especially for preparation methods of MXenes/polymer‐based EMI shielding blocks. Finally, the key scientific problems in MXenes/polymer‐based EMI shielding materials are proposed, and their development trend are prospected. Highlights: The EMI shielding mechanism and categorization of EMI shielding materials is presented.The latest research progress of MXenes/polymer‐based EMI shielding materials is reviewed.Scientific problems for MXenes/polymer‐based EMI shielding materials are proposed.Development trend of MXenes/polymer‐based EMI shielding materials is prospected. [ABSTRACT FROM AUTHOR]

IRMOF-10, derived from biphenyl-4,4′-dicarboxylic acid and zinc, is a prototype for an open cubic structure prone to interpenetration. Interpenetration can compromise MOF pore volume and surface area which drives the need to develop strategies to synthesize non-interpenetrated MOFs. In this work, an additive design strategy was employed to suppress interpenetration of IRMOF-10. The presence of the additive during traditional solvothermal synthesis yielded an activated material with the highest surface area reported to date and enabled the determination of the single crystal structure. In situ monitoring of the nucleation of crystals under polarized light provided insights into the mechanism behind interpenetration in the IRMOF-9/10 system. This work provides a roadmap to suppress interpenetration more generically in other MOFs and achieve improved surface areas and pore volumes for this prominent class of porous sorbents. [ABSTRACT FROM AUTHOR]

The practical application of lithium metal batteries (LMBs) is inevitably associated with serious safety risks due to the uncontrolled growth of lithium dendrites. Thus, to inhibit the formation of lithium dendrites, many researchers have focused on constructing three-dimensional porous current collectors with a high specific surface area. However, the homogeneous structure of porous collectors does not effectively guide the deposition of lithium metal to the bottom, leading to a phenomenon known as "top-growth." Recently, the construction of 3D porous current collectors with a lithiophilic gradient has been widely reported and regarded as an effective approach to inhibit lithium top-growth, thus improving battery safety. In this review, we summarize the latest research progress on such anode current collector design strategies, including surface modification of different base materials, design of gradient structures, and field factors, emphasizing their lithium-affinity mechanism and the advantages and disadvantages of different collector designs. Finally, we provide a perspective on the future research directions and applications of gradient affinity current collectors. [ABSTRACT FROM AUTHOR]

Paint is a versatile material that can be used to coat surfaces for which routine disinfection practices may be lacking. EPA-registered copper-containing supplemental residual antimicrobial paints could be used to reduce the bioburden on often-neglected surfaces. An interventional study was conducted by painting the walls of a preschool restroom and metal locker surfaces in two hospital locker rooms with a copper-containing antimicrobial paint to evaluate the potential for bioburden reduction compared to a non-copper-containing control paint. The antimicrobial paint reduced the bioburden on the preschool restroom walls by 57% and on lockers in one locker room by 63% compared to the control paint; no significant difference was observed between the two paint types in the second locker room. The upper quartile bacterial counts, which drive the overall risk by increasing exposure to pathogens, also exhibited 63% and 47% reductions for the antimicrobial paint compared to the control paint in the preschool restroom and the first locker room, respectively. Because detectible levels of bioburden are found on large-area surfaces such as walls and lockers, surfaces painted with copper-containing paints may make large-area surfaces that are prone to contamination safer in a way that is practical and economical. [ABSTRACT FROM AUTHOR]

Lanthanum doped MgTiO 3 (La–MgTiO 3 ; n (La): n (Mg) = 0.05:0.95) was synthesized using a sol–gel method, and a layer of this material was supported on quartz microspheres to produce La–MgTiO 3 (x%)/SiO 2 microspheres (LMTO(x%)/SiO 2 ; where x% represents the weight fraction of La–MgTiO 3 in the microspheres). The crystal size of MgTiO 3 decreased from 43.4 nm in La–MgTiO 3 to 29.2 nm in LMTO(20 %)/SiO 2 , and the bandgap energies increased from 3.34 eV (La–MgTiO 3) to 3.91 eV (LMTO(20 %)/SiO 2). The supported La–MgTiO 3 contributed the most to the total surface area of the LMTO(x%)/SiO 2 microspheres; further, the specific surface area of the microspheres decreased with decreasing La–MgTiO 3 content. The photoluminescence intensity of the microspheres was significantly lower than that of La–MgTiO 3. The activity of La–MgTiO 3 was enhanced after loading onto the quartz microspheres. The maximum photocatalytic activity was obtained using LMTO(40 %)/SiO 2 , while the azophloxine degradation efficiency slightly decreased after five reaction cycles. [ABSTRACT FROM AUTHOR]

AbstractSilica aerogel is a versatile material used in adsorption, filtration, and thermal insulation. However, its mechanical strength is a notable weakness, making it prone to damage. This study utilized molecular dynamics simulations to investigate the mechanical properties of aerogels. We compared the simulation results with the data from the experiments. The dimensionless specific surface areas of both are nearly identical at densities below 0.7 g/cm³. We explored the impact of strain rate on aerogel properties. The compression rate had minimal effects on stress and density during uniaxial compression. The specific surface area exhibited an initial increase followed by a decrease with a rising compression rate, peaking at 2 1/ns. Furthermore, we determined the solid thermal conductivity of the aerogel, which was 0.0764 W/(m·K) without strain. The solid thermal conductivity showed little variation with compression rate but was highly sensitive to density. The stretching rate during uniaxial stretching influenced the heat transfer coefficient, density, specific surface area, and stress. However, in the low-strain region (strain < 0.3), the tensile rate had a negligible impact on these performance metrics. This investigation offers a theoretical analysis of the mechanical properties of aerogels, establishing a foundational understanding of their efficient application. [ABSTRACT FROM AUTHOR]

The structural architecture of coral reefs is a known predictor of species richness, fish biomass and reef resilience. At a smaller scale, three-dimensional (3D) surface area of corals is a fundamental determinant of physical and biological processes. Quantifying the 3D surface area of corals has applications for a broad range of scientific disciplines, including carbonate production estimates, coral predation studies, and assessments of reef growth. Here, we present morphotaxon-specific conversion metrics to estimate total 3D surface area and projected 2D surface area of individual colonies from simple field measurements of colony maximum diameter. Underwater photogrammetry techniques were used to quantify surface area and estimate conversion metrics. Bayesian models showed strong non-linear (power) relationships between colony maximum diameter and both total 3D surface area and projected 2D surface area for 13 out of 15 morphotaxa. This study presents a highly resolved and efficient method for obtaining critical surface area assessments of corals for various applications, including assessments of biotic surface area, tissue biomass, calcification rates, coral demographic rates, and reef restoration monitoring. [ABSTRACT FROM AUTHOR]

Significant research is currently performed on electrochemical water splitting to solve ecological problems and energy issues. Sustainable and eco-friendly energy systems prefer to generate cost-effective electrocatalyst material with higher stability and excellent electrocatalytic activity to speed up the oxygen evolution reaction (OER) process. The current study followed a hydrothermal approach to develop a barium cerium oxide nanohybrid with g-CN (BaCeO 3 /g-CN) as an electro-catalyst for an efficient OER process in 1.0 M KOH. Physical characteristics analyses confirmed the enhanced activity of the synthesized BaCeO 3 (BCO) and BCO/g-CN nanohybrid materials. The evaluated increased performance may be ascribed to improved morphological characteristics and substantial surface area (212 m2 g−1). The nanocomposite as mentioned above (BCO/g-CN) exhibits significant potential for effective OER in electrochemical assessments due to its abundant active spots and accelerated charge transfer process. Further, the electro-catalytic activity of the composite is improved, as demonstrated by a reduced overpotential (η = 210 mV) with Tafel value (36 mV dec−1) in comparison to pristine BCO (η = 262 mV and 52 mV dec−1) for OER. The material exhibited a reduced charge transfer impedance (R ct = 0.7 Ω), confirmed by EIS analysis. It also demonstrated a substantial ECSA (electrochemical active surface area) of 237.5 cm2 as compared to the pure BCO (137.5 cm2) material. Moreover, electrocatalyst material durability for 30 h was assessed by a chronoamperometric study. Thus, BCO/g-CN exhibits a notable rise in electrochemical properties, suggesting that it is a viable candidate for prospective OER applications. [Display omitted] • BaCeO 3 /g-CN nanomaterial was synthesized by simple hydrothermal technique. • The conductivity of nanohybrid BaCeO 3 was analyzed under 1.0 M KOH for OER. • BaCeO 3 /g-CN material had higher surface area (70.6 m2 g−1) than pure BaCeO 3. • The cyclic stability of BaCeO 3 /g-CN is remarkable after 5000 cycles. [ABSTRACT FROM AUTHOR]

The detection of dopamine is of great significance for human health. Herein, Pd nanoparticles were loaded on Cu nanoplates (Pd/Cu NPTs) by a novel liquid phase reduction method. A novel dopamine (DA) electrochemical sensor based on the Pd NPs/Cu/glass carbon electrode (Pd/Cu NPTs/GCE) was constructed. This sensor showed a wide linear range of 0.047 mM to 1.122 mM and a low limit of detection (LOD) of 0.1045 μM (S/N = 3) for DA. The improved performance of this sensor is attributed to the obtained tiny Pd nanoparticles which increase the catalytic active sites and electrochemical active surface areas (ECSAs). Moreover, the larger surface area of two–dimensional Cu nanoplates can load more Pd nanoparticles, which is another reason to improve performance. The Pd/Cu NPTs/GCE sensor also showed a good reproducibility, stability, and excellent anti–interference ability. [ABSTRACT FROM AUTHOR]

Layered Ti3C2Tx MXene has been successfully intercalated and exfoliated with the simultaneous generation of a 3D silica network by treating its cationic surfactant intercalation compound (MXene-CTAB) with an alkoxysilane (TMOS), resulting in a MXene–silica nanoarchitecture, which has high porosity and specific surface area, together with the intrinsic properties of MXene (e.g., photothermal response). The ability of these innovative MXene silica materials to induce thermal activation reactions of previously adsorbed compounds is demonstrated here using NIR laser irradiation. For this purpose, the pinacol rearrangement reaction has been selected as a first model example, testing the effectiveness of NIR laser-assisted photothermal irradiation in these processes. This work shows that Ti3C2Tx-based nanoarchitectures open new avenues for applications that rely on the combined properties inherent to their integrated nanocomponents, which could be extended to the broader MXene family. [ABSTRACT FROM AUTHOR]

Dryland occupies about 46% of the global land surface area (except Antarctica) and is the most vulnerable area to climate change. From the conditions of vegetation and land surface wetness and blown sand phenomena, a simple observation system was developed to monitor regional wind erosion and applied to Khuld of Mongolia, which is sensitive to drought and desertification. The system was composed of instruments that observed blown sand, vegetation amount, land surface wetness, and landscape features related to regional wind erosion. Sixteen blown sand and eight sandstorm events were evaluated from 5 March to 5 June 2023 (i.e., during the Asian dust season in northeast Asia). The normalized difference vegetation index and visible images showed that the vegetation amount was considerably less, and the developed moisture index related to land surface wetness indicated dry conditions. Combining the results of blown sand, these indices, and visible images, land surface conditions during the analysis period were likely to occur with blown sand events. [ABSTRACT FROM AUTHOR]

Long-term monitoring studies on the transition of different land cover units to barren areas are crucial to gain a better understanding of the potential challenges and threats that land surface ecosystems face. This study utilized the Moderate Resolution Imaging Spectroradiometer (MODIS) land cover products (MCD12C1) to conduct geospatial analysis based on the maximum extent (MaxE) concept, to assess the spatiotemporal changes in barren areas from 2001 to 2022, at global and continental scales. The MaxE area includes all the pixels across the entire period of observations where the barren land cover class was at least once present. The relative expansion or reduction of the barren areas can be directly assessed with MaxE, as any annual change observed in the barren distribution is comparable over the entire dataset. The global barren areas without any land change (UA) during this period were equivalent to 12.8% (18,875,284 km2) of the global land surface area. Interannual land cover changes to barren areas occurred in an additional area of 3,438,959 km2 (2.3% of the global area). Globally, barren areas show a gradual reduction from 2001 (91.1% of MaxE) to 2012 (86.8%), followed by annual fluctuations until 2022 (88.1%). These areas were mainly interchanging between open shrublands and grasslands. A relatively high transition between barren areas and permanent snow and ice is found in Europe and North America. The results show a 3.7% decrease in global barren areas from 2001 to 2022. Areas that are predominantly not barren account for 30.6% of the transitional areas (TAs), meaning that these areas experienced short-term or very recent transitions from other land cover classes to barren. Emerging barren areas hotspots were mainly found in the Mangystau region (Kazakhstan), Tibetan plateau, northern Greenland, and the Atlas Mountains (Morocco, Tunisia). [ABSTRACT FROM AUTHOR]

Exposure to toxic gases resulting from rapid industrialization poses significant health risks living organisms including human. Consequently, researchers in this modern scientific era have shown keen interest in the selective detection of these toxic gases. The development of fast, economical, selective, and highly sensitive gas sensors has become a crucial pursuit to accurately detect toxic gases and mitigate their adverse effects on the natural environment. Graphene-based nanocomposites have emerged as promising candidates for selectively detecting toxic gases due to their extensive surface area. This review paper provides a comprehensive summary of recent advancements in graphene-based gas sensors. The paper also offers an overview of various synthetic strategies for graphene and its hybrid architectures. Additionally, it delves into the detailed sensing applications of these materials. Challenges and limitations in this field have been critically evaluated and highlighted, along with potential future solutions. [ABSTRACT FROM AUTHOR]

The membranes in polar organic chemical integrative samplers (POCIS) enclose the receiving sorbent and protect it from coming into direct contact with the environmental matrix. They have a crucial role in extending the kinetic regime of contaminant uptake, by slowing down their diffusion between the water phase and the receiving phase. The drive to improve passive sampling requires membranes with better design and enhanced performances. In this review, the preparation of standard polyethersulfone (PES) membranes for POCIS is presented, as well as methods to evaluate their composition, morphology, structure, and performance. Generally, only supplier-related morphological and structural data are provided, such as membrane type, thickness, surface area, and pore diameter. The issues related to the use of PES membranes in POCIS applications are exposed. Finally, alternative membranes to PES in POCIS are also discussed, although no better membrane has yet been developed. This review highlights the urge for more membrane characterization details and a better comprehension of the mechanisms which underlay their behavior and performance, to improve membrane selection and optimize passive sampler development. [ABSTRACT FROM AUTHOR]

Lithium insertion reactions occur via two main processes: nucleation growth in the initial stage and three-dimensional diffusion in the subsequent stage. This study aims to understand the effect of particle size on these processes, which are crucial for optimizing battery performance. The lithium insertion kinetics of MgMn2O4 particles of varying sizes is analyzed by chronoamperometry. The results show that smaller particles exhibit faster lithium insertion kinetics than larger particles. The experimental data is fitted to a solid-state reaction model that accurately describes the observed current profiles. The fitting analysis reveals that the rate constants of nucleation growth (kA) and three-dimensional diffusion (kD) are influenced by the particle size. Specifically, kA and kD increase exponentially as the particle size decreases. This relationship indicates that smaller particles have larger surface areas and shorter diffusion distances, which facilitate faster lithium insertion. In addition, the overvoltage dependence of kA remains constant across different particle sizes, indicating a consistent reaction mechanism. Overall, these findings emphasize the importance of particle size in optimizing lithium insertion kinetics in battery materials. A smaller particle size can significantly improve the reaction rates, but trade-offs, such as reduced electrode density and increased side reactions due to a larger surface area, must be considered. Thus, understanding the particle size dependence of lithium insertion kinetics is essential for designing high-performance lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Stope layout optimisation is an important sub-problem of the generic underground mining optimisation problem that contributes towards optimal ore extraction. It is a growing research area as some surface mines transition from open-pit to underground mining. Several researchers acknowledge the complexity of optimising underground mine layouts because exact methods are limited in generating three-dimensional optimal solutions, hence the growing use of metaheuristic approaches to solve the problem in three dimensions. This paper presents a PRISMA-based bibliometric mapping of stope layout optimisation approaches using R-Biblioshiny and VOSviewer software, their concomitant limitations, and suggests potential future research directions in stope layout optimisation. [ABSTRACT FROM AUTHOR]