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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]

Owing to their high porosity, open metal sites, and huge surface area, metal–organic framework (MOF) materials are commonly employed in iodine adsorption processes. Bimetallic MOFs have drawn a lot of attention since mono-metal MOFs have been unable to keep up with the demand. Bimetallic MOF materials still have drawbacks, including limited adsorption capacity, extended adsorption time, poor stability, and poor selectivity, despite their positive performance in radioactive iodine capture. It has been therefore difficult to develop adsorbents with quick iodine adsorption rates and high iodine adsorption efficiency. This study investigated the adsorption properties of a series of bimetallic MOF-74 materials (Mn–Co-MOF-74, Mn–Zn-MOF-74, and Mn–Ni-MOF-74) for radioactive iodine, as well as their design and synthesis utilizing the reflux approach. It was discovered that the adsorption performance of Mn–Ni-MOF-74 for radioiodine was superior to that of the other two bimetallic MOF-74 materials. Using the bimetallic Mn–Ni-MOF-74 as a precursor, a variety of bimetallic MOF-74 derived carbon compounds (Mn–Ni-CX) were prepared by high-temperature pyrolysis. Simultaneously, the structure of the material and the iodine adsorption characteristics have been thoroughly studied. [ABSTRACT FROM AUTHOR]

Perovskite oxides play a crucial role as catalysts in the oxygen evolution reaction (OER) owing to their distinctive structure and diverse physical and chemical characteristics. Currently, enhancing the electronic structure and specific surface area of the perovskite surface through strategic regulation poses a significant challenge in the advancement of perovskite catalyst development. Here, we propose a novel method for enhancing the OER activity of LaCoO 3 (LCO) perovskite through atomic doping and interface engineering. The La 0.6 Sr 0.4 CoO 3 –FeOOH (Fe-LSCO) composite exhibits a notable enhancement in electrocatalytic performance, manifesting a low overpotential of 296.3 mV for the oxygen evolution reaction (OER) at a current density of 10 mA cm−2, while maintaining a high level of activity for a duration of 120 h. The enhanced activity of Fe-LSCO can be attributed to oxygen vacancy defects and the increase of the active site caused by A-site-doping and amorphous nanosheets of FeOOH, which synergistic effect reduces the energy barrier for water dissociation. The highly disordered surface and high surface energy of amorphous FeOOH render it highly active. This study presents a viable interface engineering approach for manipulating the reconstruction of the active phase in high-performance perovskite-based electrocatalytic materials. [Display omitted] • Sol-gel and solution soaking treatment were used to fabricate Fe-LSCO. • The doping of Sr changes the spin state of Co ion. • The amorphous hydroxyl iron oxide can improve hydrophilicity and BET. • Fe-LSCO electrode demonstrates outstanding durability and stability. [ABSTRACT FROM AUTHOR]

This research aims to produce a highly stable, effective, economical, and novel electro-active catalyst for the oxygen evolution reaction, a significant advancement in green energy. The potential impact of this research is inspiring, as it could pave the way for more efficient and cost-effective green energy solutions. In this study, a CoFe 2 O 4 /g-CN composite catalyst was synthesized via the hydrothermal method. The samples were studied using several analytical techniques to evaluate shape and structure. This study used g-CN ultra-thin nanosheets as carriers for CoFe 2 O 4 nanoparticles to increase their active area and thus enhance their electrocatalytic performance. CoFe 2 O 4 /g-CN exhibited an improved ECSA (electrochemical active surface area) of 1337.5 cm2 and a higher Cdl value of 53.5 mF/cm2, significantly superior to the pristine CoFe 2 O 4. In comparison with pristine CoFe 2 O 4 , CoFe 2 O 4 /g-CN composite required a considerably reduced overpotential (ղ) of 200 mV to accomplish a current density (j) (10 mA/cm2). CoFe 2 O 4 /g-CN composite exhibited high stability of 35 h and a comparatively low Tafel plot (39 mV/dec). Considering all of these characteristics, it is clear that the CoFe 2 O 4 /g-CN composite could be an excellent electrocatalyst for the OER process. [Display omitted] • CoFe 2 O 4 /g-CN composite was fabricated via hydrothermal techniques for OER. • CoFe 2 O 4 /g-CN composite has a greater electrocatalytic efficiency for OER. • The small overpotential (200 mV) is required to attain 10 mA/cm2 having a Tafel plot (39 mV/dec). • CoFe 2 O 4 /g-CN demonstrated remarkable stability of 35 h. [ABSTRACT FROM AUTHOR]

Conjugated microporous polymers (CMPs) represent a promising class of materials with diverse applications due to their unique chemophysical characteristics. We introduce a novel approach for developing a TPPDA–TPA CMP- and TPPDA–ThZ CMP-based dynamic tetraphenyl-p-phenylenediamine (TPPDA) unit employing the optimum conditions for the Suzuki protocol. These CMPs incorporate triphenylamine (TPA) and 4,7-di(thiophen-2-yl)benzo[c]thiadiazole (ThZ), and exhibit distinct electronic properties. Our CMPs demonstrate high thermal durability (char yield up to 69.5 wt%) and significant surface areas (up to 132 m2 g−1). The TPPDA–TPA CMP shows a notable presence of nucleophilic bonding sites, enhancing the selective uptake of CO2, with around twofold-higher CO2 uptake (27.49 cm3 g−1) compared with TPPDA–ThZ CMP (14.67 cm3 g−1). Additionally, we evaluate the selectivity of CO2 over N2 gases on TPPDA CMPs. We analyze CO2 uptake based on key thermodynamic and kinetic principles, including the Clausius–Clapeyron equation and Henry's law. This research offers a promising strategy for enhancing CO2-adsorption capacities on CMPs. [ABSTRACT FROM AUTHOR]

The preparation of spherical TATB is a key and challenging research focus in the field of energetic materials. In this paper, microspherical TATB was successfully prepared by the oil-in-oil emulsion method with DMSO and BMIM as solvents for the first time. The optimal process conditions for oil-in-oil emulsions were obtained, and the morphology, structure, particle size distribution, specific surface area, and thermal decomposition performance of the spherical TATB were characterized. The results showed that the optimal process conditions for emulsion stability were as follows: the ratio of continuous to discontinuous phases was 5/5, Tween-80 was used as the surfactant, and the dosage of the TATB raw material was 1%, which could form a stable emulsion. The crystal structure of the TATB samples prepared from the stable emulsion did not change, but only the morphology was changed. The prepared TATB was microspherical with a particle size distribution D50 of 17.5 μm, and the specific surface area was 1.639 m2 g−1. Compared with TATB, spherical TATB exhibited a unique nanostructure on its surface, which caused its thermal decomposition exothermic peak to advance by 8.5 °C and activation energy to decrease by 82.71 kJ mol−1. This method is expected to provide new insights into the spherization of other insoluble explosives. [ABSTRACT FROM AUTHOR]

Scars can cause aesthetic or functional disturbance. Several interventions had been described to improve their appearance. We propose that the combination of some of those treatments can synergize their effects on the scar. We designed a prospective pilot study with ten patients using the patient as their own control to compare different interventions. In each patient, the scar was divided into four parts treated differently: 1. No treatment (control), 2. Fat grafting only, 3. Fat grafting and Hyaluronic Acid (HA), 4. Fat grafting, HA and with a non-fractional laser. Each part of the scar was evaluated by the Patient and Observer Scar Assessment Scale (POSAS). Treatment of the scar with the combination of the three modalities showed better results in the observer scale. In addition, a combination of fat injection, HA, and subsequent skin resurfacing with non-ablative laser showed better outcomes for all parameters on the Observer Scale except vascularity, while on the Patient Scale thickness, relief, pliability, surface area, and overall measurement were better. The combination of all three treatments tends to improve scarring results and appears to be safe and effective. However, further studies with larger samples are needed to explore the potential use of this combined treatment. [ABSTRACT FROM AUTHOR]

Here, an approach to produce a hierarchical porous Fe‐N‐C@TABOH catalyst with densely accessible high intrinsic active FeNx sites is proposed. The method involves a single‐step pyrolysis of Zn/Fe‐zeolitic imidazolate framework (Zn/Fe‐ZIF‐H) with tetrabutylammonium hydroxide (TABOH) micelles, which is obtained by utilizing TABOH as a structural template and electronic mediator at room temperature for a brief duration of 16 min. Notably, the yield of Zn/Fe‐ZIF‐H is 3.5 times that of Zn/Fe‐ZIF‐N prepared by conventional method. Results indicate that in addition to expediting synthesis and increasing yield of the Zn/Fe‐ZIF‐H, the TABOH induces a hierarchical porous structure and fosters the formation of more and higher intrinsic active FeNx moieties in Fex‐N‐C@TABOH, showing that TABOH is a multifunctional template. Crucially, the increased mesoporosity/external surface area and optimized microenvironment of Fe‐N‐C@TABOH significantly enhance ORR activity by facilitating the formation of high intrinsic active FeNx sites, increasing accessible FeNx sites, and reducing mass transfer resistance. Through structure tailoring and microenvironment optimization, the resulting Fe‐N‐C@TABOH exhibits superior ORR performance. DFT calculation further validates that the synergistic effect of these two factors leads to low ORR barrier and optimized *OH adsorption energy. This study underscores the importance of structure and electronic engineering in the development of highly active ORR catalysts. [ABSTRACT FROM AUTHOR]

Genetic generalized epilepsies (GGE) exhibit widespread morphometric alterations in the subcortical structures. Subcortical structures are essential for understanding GGE pathophysiology, but their fine-grained morphological diversity has yet to be comprehensively investigated. Furthermore, the relationships between macroscale morphological disturbances and microscale molecular chemoarchitectures are unclear. High-resolution structural images were acquired from patients with GGE (n = 97) and sex- and age-matched healthy controls (HCs, n = 184). Individual measurements of surface shape features (thickness and surface area) of seven bilateral subcortical structures were quantified. The patients and HCs were then compared vertex-wise, and shape anomalies were co-located with brain neurotransmitter profiles. We found widespread morphological alterations in GGE and prominent disruptions in the thalamus, putamen, and hippocampus. Shape area dilations were observed in the bilateral ventral, medial, and right dorsal thalamus, as well as the bilateral lateral putamen. We found that the shape area deviation pattern was spatially correlated with the norepinephrine transporter and nicotinic acetylcholine (Ach) receptor (α4β2) profiles, but a distinct association was seen in the muscarinic Ach receptor (M1). The findings provided a comprehensive picture of subcortical morphological disruptions in GGE, and further characterized the associated molecular mechanisms. This information may increase our understanding of the pathophysiology of GGE. Genetic generalized epilepsies (GGE)exhibited widespread shape alterations in subcortical structures and these morphological anomalies linked to specific neurotransmitter profiles [ABSTRACT FROM AUTHOR]

Metallic aerogels, as featured by high surface area, porosity, and self‐supported metal skeleton, are regarded as an ideal platform for developing next‐generation electrocatalysts. However, the precise adjustment of their skeleton nanostructure to enhance catalytic properties remains significantly underexplored. Herein, inspired by the impact of the metal atoms' coordination number on their reactivity, we devised and prepared dendritic Pt aerogels (DPAs) via a facile sol‐gel method. The synergy of aerogel structure and coordinatively distinct catalytic sites from dendritic morphology enables DPAs to exhibit markedly improved electrocatalytic activity and stability for methanol oxidation reaction. The mass activity and specific activity of DPAs are 1.28 A mgPt−1 and 1.5 mA cmPt−2, which are 4.1 and 3.2 times higher than those of commercial Pt/C, respectively. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have garnered extensive attention owing to their excellent biocompatibility, elevated specific surface area, and facile functionalization, as well as their diverse methods of preparation. In recent times, CDs have been applied for anti‐corrosion and obtained some significant results. In this work, the preparation methods of CDs are first briefly introduced, and the relative merits of different approaches are highlighted. Subsequently, the application of CDs in the realm of corrosion inhibitors is discussed, and the corrosion inhibition effects and mechanism of nitrogen‐doped CDs, nitrogen and sulfur‐co‐doped CDs, as well as CDs functionalized with other elements and nitrogen‐co‐doped are summarized. Finally, the application of CDs and functionalized CD‐modified coatings for anti‐corrosion and their protective mechanism is analyzed in detail. This review summarizes recent progress in research related to CDs and heteroatom‐doped CDs in anti‐corrosion applications and anticipates the prospects and applications of CDs in corrosion protection. With their unique properties and versatile applications, CDs are expected to assume a progressively pivotal role in the advancement of cutting‐edge corrosion protection technologies. [ABSTRACT FROM AUTHOR]

With the continuous development of high‐end electronic information technologies such as 5G communications, thermal management is an urgent issue in the electronic and circuit industries due to the miniaturization, functionalization and integration. Recently, polymer‐based composites with the fillers of hexagonal boron nitride (h‐BN) have been regarded as promising candidates resulting from their excellent thermal conductivity (TC), good insulation and remarkable comprehensive properties. However, the high surface inertness of h‐BN itself, incompatibility with matrix and other fillers and mismatch of phonon‐spectrum will bring about the matrix/filler and filler/filler interfacial thermal resistance (ITR), which will greatly decline the TC of the composites, and limit their thermal management ability. Therefore, how to design, regulate and improve the interfacial states in composites and eventually enhance the TC is a current challenge. Researchers have made great effort to reduce the ITR of the composites to improve their TC. However, a comprehensive summary and analysis of researches on the improvement methods of the interface states in composites in the past 3 years is still lacking. In this work, the commonly used mechanism models, and simulation methods for calculating and predicting TC was summarized. From perspectives of Synthesis of h‐BNNs, modification, orientation, bridging and three‐dimensional structures construction, we reviewed strategies for improving the interface states in composites, and focused on the ITR regulation and TC improvement. The improvement effects of various methods on TC were compared. The development trend of high TC composite materials was prospected. Highlights: Crystallinity, defect, size, flatness, thickness of hexagonal boron nitride nanosheets (BNNSs) affect interfacial thermal resistance (ITR).Nature of interaction between adjacent layers of BNNS need exploited.Interface and defect are root cause of extra phonon scattering.Shape, density, surface area, distribution and compatibility reduce ITR.Theory, model, simulation methods need developed on different levels. [ABSTRACT FROM AUTHOR]

Coal gasification fine slag (CGFS) is rich in unburned residual carbon, silica and alumina, and has a large specific surface area, making it a potential polymer‐reinforcing filler. Tea polyphenol (TP)‐modified coal gasification fine slag (TP‐CGFS‐T) was prepared using flotation and modification methods in this study. The effects of unmodified and modified CGFS‐T on the sulfurization performance, processing properties, thermal stability, fracture morphology, and mechanical properties of natural rubber composite materials were investigated. Results indicated that after TP modification, CGFS‐T exhibited highly uniform dispersion on the surface without the agglomeration of fillers. When the dosage of TP‐CGFS‐T was 20 phr, the comprehensive performance of the natural rubber (NR) composite material was optimal, with a tensile strength of 12.12 MPa, the elongation at break of 1208.83%, the tear strength of 30.94 kN/m, and the shore hardness of 38.7 A. As the amount of TP‐CGFS‐T increased, the scorch time of NR increased, which enhanced the processing safety of rubber. This study provides a strategy for treating CGFS, which can both reduce the pollution caused by CGFS and save costs for NR composite materials. Highlight: The CGFS is separated into concentrate and tailings by flotation.The compatibility between fillers and the matrix is enhanced by TP modification of CGFS‐T.The composite materials show excellent mechanical and processing properties. [ABSTRACT FROM AUTHOR]

MXene is a novel two-dimensional layered nanomaterial with a very large specific surface area and abundant surface functional groups, endowing it with unique physical and chemical properties. MXene can be compounded with other functional materials to significantly improve the performance of MXene composites or broaden their application scope. Meanwhile, with the development of flexible composite preparation technology, it has promoted the continuous expansion of its application fields. The introduction and combination of different materials can improve the performance of flexible composites and make them have a broader application prospect. In recent years, researchers have started preparing MXene materials as flexible composites for applications such as supercapacitors, sensors, electromagnetic shielding and thermal management. This paper gives a brief introduction to flexible composites and MXene materials, reviews the applications of MXene based flexible composites in various fields as well as the research progress, and provides an outlook on their future development direction. [ABSTRACT FROM AUTHOR]

Highlights Application of the global Gauss–Bonnet theorem for the prediction of changes in Gaussian curvature for double curvature laminate geometries due to shrinkage is developed for non‐isometric deformation states where in surface area change accompanies changes in curvature. The transition between isometric and non‐isometric deformation is strongly influenced by the ratio of the principal radii of curvature of the double curved surface and a relationship is proposed by the authors to accommodate the transition. Examples for the radii of curvature ratios of 2, 3, and 4 are compared to results from finite‐element simulations and the developed relationship is shown to be accurate within 0.55%. Furthermore, these results demonstrate that isometric deformation state can be taken as an adequate representation for double curvature toroidal laminate geometries of ρ2/ρ1$$ {\rho}_2/{\rho}_1 $$ >10 and the class of materials studied in this work. Shrinkage induced deformation in multi‐curvature composite laminates is a recurring issue in polymer composite manufacturing. Thermal, crystallization and cure shrinkage are the dominant sources of shrinkage deformation in polymer composite systems. Isometric deformation of multi‐curvature, symmetric laminates composite is defined by the absence of membrane strain. The Gauss–Bonnet theorem provides a platform for determining radii of curvature changes in multi‐curvature symmetric laminates, Non‐isometric deformation of symmetric laminates can be treated by the Gauss–Bonnet theorem for radii of curvature ratios that correspond to geometric self‐constraint. The above highlights yield insight into the anticipated geometric distortions due to shrinkage in polymer composites. [ABSTRACT FROM AUTHOR]

Nickel titanate (NiTiO3) nanostructured materials have gained extensive attention in the field of lithium‐ion batteries (LIBs) due to their high theoretical capacity and low cost. However, NiTiO3 exhibits low conductivity and significant volume changes during cycling, resulting in capacity decay and poor cycling stability. Herein, we propose a feasible strategy to enhance the cycling performance of NiTiO3 nanostructures by adjusting their morphology. By manipulating the choice of solvent employed in the synthetic process, we obtain NiTiO3 microbars (NTO MBs) through self‐assembly of NiTiO3 nanoparticles (NTO NPs). When utilized as an anode material in LIBs, NTO MBs exhibit a capacity of 410 mAh g−1 after 200 cycles at 100 mA g−1, surpassing that of NTO NPs (212 mAh g−1). The improved performance of NTO MBs is attributed to their unique porous bar‐like structure, composed of numerous NPs, which provides a substantial storage space for Li+ ions owing to its larger specific surface area. Additionally, the porous structure accelerates the diffusion of Li+ ions and electron transfer. To gain a profound understanding of the enhanced performance through morphology adjustment, we conduct a comprehensive investigation on the growth mechanism of NTO MBs. This work provides valuable insights into the mechanism governing the morphology control of NTO MBs, facilitating the rational design and synthesis of tailored materials with enhanced performance for LIBs. [ABSTRACT FROM AUTHOR]

Variations in configurational entropy greatly influence the electrochemical behavior of materials; those featuring expanded surface areas, numerous active sites, and accelerated reaction kinetics are highly valued for their superior electrocatalytic properties. In this study, a Berthollide compound is introduced, designated as Cu3Sb0.93Bi0.06Sn0.01S2Se2 (C(ABT)(SSe)). This material, cations, and anions co‐doped Cu3SbS4 (CAS), exhibit significantly enhanced storage performance in potassium‐ion batteries (PIBs). The introduction of foreign elements improved conductivity, while dual‐site conversion and alloying elements enhanced ion diffusion, charge transfer, and electrode kinetics. Regulating configurational entropy created more active sites for Sb. Using high‐capacity Sb and S as primary components, material's configurational entropy is precisely adjusted through active element doping, forming a non‐stoichiometric structure with thermodynamically stable defect active sites. The synergistic effect of trivalent active metals, particularly high‐valence Sb5+, demonstrated superior electrochemical performance compared to materials with unregulated entropy values. Compared to CAS, with the increase in configurational entropy to 0.975 R, the K+ diffusion energy is reduced by 40% and increasing electronic conductivity by 2.6 times, boosting high rate performance (10 A g−1), and showing 49.5% higher capacity after 700 cycles. This novel entropy regulation strategy offers new insights into the design of multi‐element configurational entropy PIBs. [ABSTRACT FROM AUTHOR]

This paper presents the determination method of the exact geographical coordinates of aboveground nuclear tests (NT) epicenters based on the radioecological study results the example of the Semipalatinsk Nuclear Test Site. By testing the NT Epicenter software for determining the exact geographic coordinates of the NT centers, it was established that it is indeed possible to determine the exact coordinates of most of the aboveground NTs. Their locations are currently determined by the presence are currently determined by the presence of technogenic disturbance of the soil surface in the area of the alleged epicenter (the presence of a crater), as well as by comparing maps of radioactive contamination and a space image. The accuracy of the precise coordinates of the NT is highly dependent on the density of the auxiliary grid: the smaller the pitch of the auxiliary grid, the higher the accuracy of the NT epicenter. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have received widespread attention for their large specific surface area, porous structure, and tunable particle size. MOFs can be utilized as precursors to prepare structurally diverse bimetallic oxides, which exhibit outstanding electrochemical properties as anode materials for lithium-ion batteries (LIBs). This paper introduces the study of MOF-derived bimetallic oxides as anode materials for LIBs, focusing on the application of MOF-derived manganese-, cobalt-, iron-, and vanadium-based bimetallic oxides in LIBs. MOF-derived bimetallic oxides, with the advantages of tunable compositions and nano-structures, are capable of further contributing to the enhancement of electrochemical performances. Finally, the problems of these derived materials in the application of LIBs are prospected, and reliable solutions and future development prospects are proposed. [ABSTRACT FROM AUTHOR]

Football teams' tactical organization on the pitch is usually represented by the surface area. Considering the different shapes adopted by the teams during the match, the role of the tactical variability for success is lacking. The aim of this study was to explore and to evaluate the association between recurrent states of tactical organization and technical performance during football matches. A total of 28 teams of Brazilian First Division Championships were analysed. Teams' surface area shapes were represented by the maximum value of the Multiscale Fractal Dimension in each timestamp, producing a time series. Recurrences of states of tactical organization were determined via recurrence plots and recurrence quantitative analysis during attacking and defending phases, and considering the whole match. The outcomes were correlated with nine traditional technical performance indicators. The main results showed that structural recurrence or variability on tactical organization is associated with performance success during the defending and attacking actions. Recurrence plot and measures based on the recurrence density proved to be valuable tools to represent teams' dynamics. [ABSTRACT FROM AUTHOR]

Ventilation systems of operating rooms (ORs) are significantly important in preventing postoperative wound infections that can cause morbidity and mortality after surgery in or out of the hospital. This study aims to identify the optimum overpressure for efficient operation while reducing the risk of surgical site infections (SSIs) based on the actual OR with the help of computational fluid dynamics. The species transport model, Lagrangian discrete phase model, and turbulent standard k- ε model are mainly used for the transient numerical study to improve the performance of the OR and reduce SSI cases. Four OR schemes were initially calculated for the best location of the patient on the surgical table. The results revealed that the modified position 90˚ is the best location with the minimum CO2 and BCP concentrations. The investigated operating room could host up to ten surgical members with the optimum overpressure of 5.89 Pa and 0.56 m/s of supply velocity under the standard cleanliness level. Modifying the supply surface area will enhance the performance of the operating room by providing a cleaner zone and maintaining the desired room pressure, even with a low airflow rate. This optimization scheme could guide practical applications in all positively pressurized operating rooms to address issues related to overpressure effects. [ABSTRACT FROM AUTHOR]

Converting the abundant biomass resources in nature into fine chemicals can not only reduce carbon emissions but also effectively deal with the depletion of fossil energy, which is of strategic significance for sustainable development. In this paper, by optimizing the content of bimetallic components, highly active co‐doped Co1Cu3 bimetallic silicate was designed and synthesized. After reduction, a highly dispersed and stable Co1Cu3/SiO2 catalyst was obtained, which was used to catalyze the aqueous phase hydrogenation of furfural (FFR) to cyclopentanone (CPO). Compared with the traditional supported catalyst, the Co1Cu3/SiO2‐ammonia evaporation (AE)‐300 catalyst prepared by AE has the best performance. Under the optimal reaction conditions, the conversion of FFR was as high as 95.1 % and the selectivity of CPO was 88.6 %. This high activity can be attributed to the formation of highly dispersed and uniform metal active sites with low content of Co. At the same time, the formation of flocculent silicate enhances the synergism between CoCu and SiO2 support and increases the specific surface area of the catalyst. In addition, the experimental results show that the reaction carbon balance will be destroyed with the high concentration of FFR solution. [ABSTRACT FROM AUTHOR]

Conventional metal sulfide (SnS2) gas-sensitive sensing materials still have insufficient surface area and slow response/recovery times. To increase its gas-sensing performance, MoS2 nanoflower was produced hydrothermally and mechanically combined with SnS2 nanoplate. Extensive characterization results show that MoS2 was effectively integrated into SnS2. Four different concentrations of SnS2–MoS2 composites were evaluated for their NO2 gas sensitization capabilities. Among them, SnS2–15% MoS2 at 170 °C demonstrated the greatest response values to NO2, 7.3 for 1 ppm NO2, which is about three times greater than the SnS2 sensor at 170 °C (2.58). The creation of pn junctions following compositing with SnS2 was determined to be the primary reason for the composite's faster recovery time, while the heterojunction allowed for the rapid separation of hole–electron pairs. Because the MoS2 surface has multiple vacancy defects, the adsorption energy of these vacancies is significantly higher than that of other places, resulting in increased NO2 adsorption. Furthermore, MoS2 can serve as active adsorption sites for SnS2 micrometer sheets during gas sensing. This study may help to build new NO2 gas sensors. [ABSTRACT FROM AUTHOR]

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Graphitic carbon nanocages (CNCs) have garnered attention as viable candidates for potassium storage, primarily due to their notable crystallinity, large surface area, and rich porosity. Yet, the development of a rapid, scalable, and economically feasible synthesis approach for CNCs persists as a formidable challenge. This study presents a rapid (millisecond‐scale) and scalable (gram‐scale) method for fabricating mesoporous CNCs characterized by high purity and orderly graphitic structures, utilizing the flash Joule heating technique. Employed for potassium storage, the CNC electrode developed herein exhibits exceptional performance metrics, including initial capacity, rate capability, and cycling stability, surpassing numerous carbonaceous materials previously documented. Impressively, it delivers a high initial capacity of 312.3 mAh g−1 at 0.1 A g−1, maintains 175.1 mAh g−1 at a high rate of 2.0 A g−1, and retains 219.6 mAh g−1 over 1000 cycles at 1.0 A g−1. Molecular dynamics simulations and in situ characterizations are employed to elucidate this robust behavior. This work underscores the significant advantages of the flash Joule heating technique in synthesizing carbonaceous materials for potassium storage applications. [ABSTRACT FROM AUTHOR]

Petty proved that a convex body in ℝn has the minimal surface area among its SL(n) images if and only if its surface area measure is isotropic. In this paper, we seek the general minimal Orlicz surface area of a convex body containing the origin in its interior among its SL(n) images for a measure μ on ℝn with density that has a positive degree of homogeneous, demonstrate the existence of the extreme body, and establish a necessary condition for the extreme body. Moreover, we also provide a counterexample to negate the uniqueness of the extreme body attaining the general minimal Orlicz surface area for μ. [ABSTRACT FROM AUTHOR]

Materials often fail prematurely or catastrophically under load while containing voids, posing a challenge to materials manufacturing. We found that a metal (gold) containing spherical voids with a fraction of up to 10% does not fracture prematurely in tension when the voids are shrunk the submicron or nanometer scale. Instead, the dispersed nanovoids increase the strength and ductility of the material while simultaneously reducing its weight. Apart from the suppressed stress or strain concentration, such structure provides enormous surface area and promotes surface-dislocation interactions, which enable strengthening and additional strain hardening and thus toughening. Transforming voids from crack-like detrimental defects into a beneficial “ingredient” provides an inexpensive and environmentally friendly approach for the development of a new class of lightweight, high-performance materials. [ABSTRACT FROM AUTHOR]

Plasma‐activated mist (PAM) has seen increasingly widespread applications in areas such as surface disinfection and fog cultivation. The high‐resolution time diagnostics of ns pulse plasma interacting with micron‐sized droplets under high‐humidity conditions is challenging to achieve with existing experimental methods. This paper employs a global model to study the interaction between plasma and droplets, offering a detailed analysis of the plasma's transition from the gas phase to the liquid phase. It was discovered that in high‐humidity environments, hydrated ions become the predominant ion species. These acidic active substances in PAM droplets are the primary factors in the mist's ability to kill bacteria. The paper further examines how variations in droplet size and discharge voltage influence the PAM's activity. [ABSTRACT FROM AUTHOR]

ABSTRACT We present a groundbreaking technique for controllably synthesizing nanosized semiconductive two‐dimensional (2D) (Cu–S)n metal–organic framework (MOF)/graphene nanocomposites for electrochemical sensing of neurotransmitter 2‐phenethylamine (PEA). The (Cu–S)n MOF size is controlled by graphene oxide proportions, enhancing electrocatalytic activity. The modified electrode exhibits a surface area increase from 0.0639 to 0.1906 cm2 and impressive limit of detection (0.0156 and 0.004 μM) within linear ranges of 15–200 μM and 1–10 μM, offering exceptional selectivity, reproducibility, and repeatability for biosensing. [ABSTRACT FROM AUTHOR]

In this study, multifibrillar carbon and carbon/ceramic (C/SiCON) fibers consisting of thousands of single nanofibers are continuously manufactured. The process starts with electrospinning of polyacrylonitrile (PAN) and PAN/oligosilazane precursors resulting in poorly aligned polymer fibers. Subsequent stretching leads to parallel aligned multifibrillar fibers, which are continuously stabilized and pyrolyzed to C or C/SiCON hybrid fibers. The multifibrillar carbon fibers show a high tensile strength of 911 MPa and Young's modulus of 154 GPa, whereas the multifibrillar C/SiCON fibers initially have only tensile strengths of 407 MPa and Young's modulus of 77 GPa, due to sticking of the nanofibers during the stabilization in air. Additional curing with electron beam radiation, results in a remarkable increase in tensile strength of 707 MPa and Young's modulus of 98 GPa. The good mechanical properties are highlighted by the low linear density of the multifibrillar C/SiCON fibers (~ 1 tex) compared to conventional C and SiC fiber bundles (~ 200 tex). In combination with the large surface area of the fibers better mechanical properties of respective composites with a reduced fiber content can be achieved. In addition, the developed approach offers high potential to produce advanced endless multifibrillar carbon and C/SiCON nanofibers in an industrial scale. [ABSTRACT FROM AUTHOR]

Nanoporous metals, fabricated via dealloying, offer versatile applications but are typically limited to unimodal porous structures, which hinders the integration of conflicting pore‐size‐dependent properties. A strategy is presented that exploits the homologous temperature (TH)‐dependent scaling of feature sizes to generate hierarchical porous structures through multistep dealloying at varied TH levels, adjusted by altering dealloying temperatures or the material melting points. This technique facilitates the creation of monolithic architectures of bimodal porous nickel and trimodal porous carbon, each characterized by well‐defined, self‐similar bicontinuous porosities across distinct length scales. These materials merge extensive surface area with efficient mass transport, showing improved current delivery and rate capabilities as electrodes in electrocatalytic hydrogen production and electrochemical supercapacitors. These results highlight TH as a unifying parameter for precisely tailoring feature sizes of dealloyed nanoporous materials, opening avenues for developing materials with hierarchical structures that enable novel functionalities. [ABSTRACT FROM AUTHOR]

Cobalt‐free LiNi0.5Mn1.5O4 (LNMO) is a promising cathode material for high‐energy and power‐density lithium‐ion batteries (LIBs). However, its commercial adoption is hindered by rapid capacity degradation due to the unstable LNMO/electrolyte interface caused by LNMO's high operating voltage. Structural degradation from Jahn–Teller distortion and metal‐ion dissolution also contributes to poor cycling stability. Additionally, producing industrial‐grade LNMO with high tap density, low surface area and reduced metal‐ion dissolution is challenging. This study addresses these challenges through a rational material design approach, synthesizing LNMO with large spherical secondary particles (>14.0 µm) and high tap density (>2.0 g cm−3). The primary particles (1.5–6.0 µm) exhibit a truncated‐octahedral shaped morphology that predominantly exposes (111) surface facets, with fewer (100) surfaces, stabilizing the LNMO/electrolyte interface, reducing metal dissolution, and enhancing lithium‐ion kinetics. Silicon infusion into grain boundaries further improves structural integrity by forming a silicon‐rich phase. The tailored LNMO demonstrates exceptional rate capability, cycling stability, and improved interfacial kinetics, significantly advancing the potential for cobalt‐free LNMO in high‐voltage LIBs. This work highlights the importance of tailored cathode material design for achieving the performance and stability required for emerging high‐voltage LIBs applications. [ABSTRACT FROM AUTHOR]

Crystalline porous framework materials have attracted tremendous interest in electrocatalytic CO2 reduction owing to their ordered structures and high specific surface areas as well as rich designability, however, still suffer from a lack of accuracy in regulating the binding strength between the catalytic sites and intermediates, which is crucial for optimizing the electrocatalytic activity and expanding the product types. Herein, we report three new kinds of vinylene‐linked metal‐covalent organic frameworks (TMT‐CH3‐MCOF, TMP‐CH3‐MCOF and TMP‐MCOF) with continuously tunable D‐π‐A interactions by adjusting the structure of the monomers at the molecular level for realizing efficient electroreduction of CO2 to formate for the first time. Interestingly, compared with TMT‐CH3‐MCOF and TMP‐MCOF, the TMP‐CH3‐MCOF exhibited the highest HCOO− Faradaic efficiency (FEHCOO‐) of 95.6 % at −1.0 V vs RHE and displayed the FEHCOO‐ above 90 % at the voltage range of −1.0 to −1.2 V vs. RHE, which is one of the highest among various kinds of reported electrocatalysts. Theoretical calculations further reveal that the catalytic sites in TMP‐CH3‐MCOF with unique moderate D‐π‐A interactions have suitable binding ability towards the reaction intermediate, which is beneficial for the formation of *HCOO and desorption of *HCOOH, thus effectively promoting the electroreduction of CO2 to formate. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) materials, due to their unique porous structure, large surface area, low density, and customizable ligands, have the potential to serve as catalytic carriers. They can address the limitations of pure platinum (Pt), including susceptibility to toxicity and poor stability during catalytic processes. In this study, ZIF‐8@ZIF‐67 derived N‐doped carbon‐loaded ultra‐low Pt catalysts (ZIF@PDA/Pt‐x‐y) were prepared using zeolitic imidazolate frameworks (ZIFs) as carriers. Meanwhile, the effects of dopamine hydrochloride (DA) incorporation and reaction temperature on the topography structure and electrocatalytic properties of the synthesized samples were mainly investigated. The introduction of polydopamine (PDA) relieved the loss of the nitrogen source of ZIF due to high temperature. The electrocatalytic performances of synthetic samples for methanol oxidation were investigated using electrochemical methods, and ZIF@PDA/Pt‐5‐900 exhibited the most favorable catalytic effect. Compared to other samples and the Pt/C catalyst (20 %), ZIF@PDA/Pt‐5‐900 demonstrated the largest electrochemically active surface area (ECSA, 66.25 m2 mgPt−1), higher electrocatalytic amount activity (1719.28 mA mgPt−1) and superior stability. Overall, this finding offers a new approach for preparing catalysts for direct methan ol fuel cells (DMFCs). [ABSTRACT FROM AUTHOR]

The promise of using 2D materials for hydrogen storage has broad prospects, ascribe to their significant specific surface area and lightweight properties. In this work, the hydrogen storage capability and reversible storage mechanism of 2D penta-SiCN material are investigated based on the first-principles computational method. Thermal stability of penta-SiCN is calculated by the ab-initio molecular dynamics (AIMD) simulation and root-mean-square displacement (RMSD) algorithm. It has been found that penta-SiCN is thermodynamically stable even after adsorbing hydrogen molecules. Taking into account the benchmarks of average and continuous adsorption energies of the adsorption systems, a pristine 2 × 2 × 1 penta-SiCN substrate has the ability to adsorb up to 26H 2 molecules, which results in a maximum hydrogen storage capacity of 10.80 wt%. According to the semi-empirical calculation method that based on the thermodynamic analysis, the penta-SiCN adsorption system has a high reversible hydrogen storage capacity of 9.57 wt% within the adsorption and desorption application working conditions. The results proposed in this study demonstrates that penta-SiCN exhibits considerable promise for hydrogen storage with its substantial hydrogen storage capacity, exceptional reversibility, and eco-friendly characteristics. [Display omitted] • Pristine penta-SiCN is a promising material for hydrogen storage. • Theoretical predictions by combining DFT and a semi-empirical calculation method. • The gravimetric densities of penta-SiCN can reach 10.80 wt%. • The penta-SiCN has a high reversible hydrogen storage capacity of 9.57 wt% within the adsorption and desorption working environment. [ABSTRACT FROM AUTHOR]

TiO 2 -based photoelectrocatalysts are synthesized by anodization at 90, 70 and 50V, using ethylenediamine to incorporate C and N elements (i.e. formation of coordinated complexes). The analysis is focused on determining the effects of oxygen vacancies, crystallite size, phase type, band gap size, elemental surface composition, roughness, and thickness of the photoelectrodes, to establish those influencing the photoelectroactivity of H 2 production. H 2 is generated with irradiations simulating solar conditions, and only visible-light. The photoelectrode formed at 70V develops the largest photocurrent, and consequently the largest H 2 production. It is revealed that the lowest content of oxygen vacancies, the highest amount of elemental C and O at the surface, and the reduction of the main band gap in this photoelectrode substantially control the photoactivity of this reaction. While the roughness and thickness of the coatings, the crystallite size, the specific surface area, and the surface compositions of elemental Ti and N are found to be negligible. [Display omitted] • Ethylenediamine was effective to incorporate C and N species into anodized TiO 2. • C and N incorporations reduced the main band gaps of all (CN)–TiO 2 photoanodes. • Oxygen vacancies, surface contents of C and O, and band gap size control H 2 yield. • Roughness, thickness, and crystallite size of catalysts do not impact H 2 activity. • Specific area and surface compositions of Ti and N are negligible for H 2 generation. [ABSTRACT FROM AUTHOR]