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ZnCl2 impregnation of the cellulosic precursor is an effective way to generate carbon catalysts with a mesoporous structure and high specific surface area. Herein, we attempt to explore the synthesis of Citrus Limonum Pericarpium (lemon peel), an activated biochar catalyst produced via pyrolysis and consequent sulfonation. The obtained biochar catalyst exhibited notable characteristics, including a high surface area of 863.0 m2 g−1 and a substantial sulfur content of 4.02 wt.% (1.25 mmol g−1) by EDX. Following, analytical techniques, such as scanning electron microscopy, BET, X‐ray diffraction, Fourier‐transform infrared, and TGA, were conducted for a comprehensive analysis of the catalyst. Subsequently, we applied the catalyst to optimize the transesterification process of Jatropha curcas oil (JCO), yielding an impressive 95.2% ± 0.4% yield. The optimization parameters were established with a reaction duration of 60 min, a temperature of 100°C, 8 wt.% catalyst, and JCO: MeOH ratio of 1 : 20. Catalyst reusability was probed over seven subsequent cycles with the final yield observed of over 88.4% ± 0.6%, while the decrease in yield was explained by EDX analysis. In summary, our investigation successfully navigated the synthesis and practical application of a sulfonated porous biochar catalyst for JCO transesterification, achieving noteworthy yields while addressing environmental concerns. [ABSTRACT FROM AUTHOR]

This research looks into the domination of flow boiling on the efficiency and sustainability of refrigeration and air conditioning systems. Specifically, it focuses on the characteristics related with heat transfer of refrigerant R134a within both smooth and microfin tubes, each having 9.52 mm outer diameter. The features of microfin tube have distinct configuration with a 46° apex angle and a 22° helix angle, resulting in a surface area 1.62 times greater in comparison to smooth tube. Through a comprehensive experimental analysis, the study examines the influence of key parameters (mass flux; saturation temperature; heat flux; and average vapor quality) on heat transfer coefficients (HTCs). Notably, the HTC exhibits significant enhancements at mass flux of G = 125 kg m⁻2·s⁻1, encountering challenges related to dry‐out at elevated vapor quality levels. The results reveal that microfin tubes consistently outperform smooth tubes, exhibiting heat transfer coefficients up to 270% higher across various operational conditions. Furthermore, the experimental data are rigorously validated through computation analysis with authentic flow boiling heat transfer models, demonstrating strong agreement. [ABSTRACT FROM AUTHOR]

Mesoporous materials are special nanoporous materials containing well-defined mesochannels with a pore diameter between 2 and 50 nm. The high surface area, ordered structure, tunable pore size, and easiness of functionalization have made mesoporous silica powder and thin films interesting materials for a wide range of applications including drug delivery, absorption, separation, catalysis, energy conversion, and storage. The sol–gel process has emerged as a promising technique for the synthesis of nanostructured mesoporous silica materials as it provides the advantages of low-temperature processing and easy control of the synthesis parameters. Although it offers several advantages over other synthesis techniques, it also has the drawbacks of high sensitivity to processing conditions. Hence, this review paper aims to give critical insights into the sol–gel process, the chemistry of sol–gel silica, the formation mechanism of mesoporosity, and the effects of the reaction parameters. A good understanding of these phenomena is essential to better control and optimize the properties of the final material for specific needs and applications. Additionally, this review paper discusses the different methods applied to the synthesis of nanostructured ordered mesoporous thin film silica, including the Electrochemically Assisted Self-Assembly method of synthesis. The EASA method is a novel and promising technique for the synthesis of well-ordered and vertically aligned pore channels of mesoporous thin films as it is required for mass transport applications. Moreover, the effects of sol composition, pH, applied potential, and deposition time on the final thickness of the thin film are elaborated on in detail. Furthermore, this comprehensive review highlights the potential and opportunities for future research and development in the area to further advance and use its full potential advantages. [ABSTRACT FROM AUTHOR]

The air-conditioning systems have become an indispensable part of our daily life for keeping the quality of life. However, to improve the thermal comfort and reduce energy consumption is crucial to use the air conditioners effectively with rapid development of artificial intelligence technology. This study explored the correlation between the response of human physiological parameters and thermal sensation voting (TSV) to evaluate the comfort level among various cold and hot stimulations. The variations of the three physiological parameters, which were body surface temperature, skin blood flow (SBF), and sweat area on the skin surface, and TSV values were all positively correlated with the stimulation amount under the stimulation of cold wind, hot wind, and heat radiation, but the relationship was not completely linear. Among the three physiological parameters, the forehead skin temperature has the closest relationship with TSV, followed by the SBF and sweat. Among three stimulations, the cold wind stimulation causes the closest relationship between TSV and forehead temperature, followed by the radiation and hot wind stimulations. Through three different machine learning models, namely, random forest (RF) model, support vector machine (SVM) model, and neural network (NN) model, the stimulation of cold wind, hot wind, and heat radiation was applied to investigate the variation of the three physiological parameters as the input of the models. Moreover, the models were evaluated and verified by TSV. The results revealed that among the three different machine learning methods, RF had the best accuracy. The established thermal comfort models can predict the real-time user's thermal comfort feeling, so that air-conditioning equipment's performance can be optimized to create a healthy and energy-saving comfortable environment. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) exhibit size-dependent optical properties, where both the absorption and fluorescence energy levels vary with QD size. However, this dependence results in a discontinuity of intrinsically accessible energy levels for the bandgap, posing challenges in achieving precise energy tuning within a specific range. Herein, we demonstrate emission energy control of QDs with identical absorption energy levels by manipulating the spatial arrangement of QDs within QD–polymer complexes through hydrophobic interactions. The phase behavior of the QD–polymer complexes was modulated by adjusting the mass fraction of hydrophilic and hydrophobic blocks in the block copolymer, utilizing two types of amphiphilic block copolymers and varying temperatures. The QDs were spontaneously trapped within the hydrophobic region of the polymer template in water, resulting in spherical, cylindrical, and vesicle structures of QD–polymer complexes, corresponding to spherical, cylindrical, and layered assemblies of QDs, respectively. Depending on the QDs' location within the QD–polymer complex, the surface area in contact with water varied, leading to different degrees of oxidation and, consequently, a change in the fluorescence energy level of QDs. This study introduces a novel method to fine tune the emission energy (<15 eV) of QDs by adjusting the polymer form factor without complicated procedures. [ABSTRACT FROM AUTHOR]

Initially, mixed oxide of ZrO2.TiO2 support was synthesized by the sol-gel method, and then after vanadium was incorporated, phosphomolybdic acid (VPMA) was synthesized by the hydrothermal method. VPMA supported on ZrO2.TiO2 support of various VPMA loadings that were synthesized by the impregnation method. The structure, surface area, acidity, and morphology of the materials were analysed by X-ray diffraction, BET surface area, ammonia TPD studies, and SEM analysis, respectively. The XRD result shows crystallites of zirconia, titania, and Keggin ion of VPMA catalysts, and also, below 20 wt% of VPMA loading, crystallites of Keggin ion are not observed. BET surface area analysis reveals that increase of VPMA loading, surface area was sharply declined at higher loadings. Ammonia TPD analysis finds that acidity is inclined with VPMA loadings. SEM studies reveal that bulk formation of the active phase is observed at higher loadings. Esterification of acetic acid was tested over VPMA/ZrO2.TiO2 catalyst that exhibited higher activity during reaction than pure VPMA catalyst. These findings were well correlated with surface area and acidity loadings. [ABSTRACT FROM AUTHOR]

This paper examined the usage of thermally conductive angled fins within an annular conduit through numerical simulation. Despite the thermally conductive nature of the fins increasing heat transfer surface area, this investigation found that using an optimal fin angle can promote the generation of vortical structures which aid heat transfer. Using ANSYS-Fluent with the SIMPLEC algorithm and the SST κ − ω turbulence model, this research found that heat transfer performance improved considerably when the generated vortices were sufficiently large and robust. However, the type of generated vortex had a profound impact when optimising for higher performance evaluation criterion (PEC) values. Longitudinal vortices improved heat transfer performance with a low impact on pressure drop increase, unlike transverse vortices, which increased pressure drop significantly. The fin angles of 50° and 60° yielded high heat transfer performance without much increase in pressure drop, thus resulting in higher PEC values. Additionally, using fin heights that correlate to 20% to 60% of the gap between the concentric walls was ideal when designing heat exchangers to achieve higher PEC values. The results of this numerical investigation have been validated both theoretically and experimentally to ensure accurate reporting of the findings. [ABSTRACT FROM AUTHOR]

In the current study, an accurate strategy was developed to detect the surface damage of the strawberries, because the existing indicators for evaluating surface damage are single, resulting in low accuracy of judgment for damage detection. Strawberry surface damage can be divided into three specific categories: outline depression, surface oxidation, and surface damage. The methodologies employed in this study are experimental analysis and comparative validation. The outline, area of surface damage, and surface reflectance of strawberries were analyzed using visual and hyperspectral data. Principal component analysis was used to evaluate the damage characteristics comprehensively. A four-finger rigid manipulator having one degree of freedom was selected, and 280 samples were analyzed (the manipulator grasped 85% of them, and 15% were not treated). The accuracy of damage detection based on the outlines, area of surface damage, and surface reflectance of strawberries was 88.75%, 91.25%, and 75%, respectively. The evaluation method proposed in this paper improved detection accuracy by 10.79%, 7.76%, and 31.1%, respectively. Therefore, this method could contribute to the design of manipulators to further improve fruit production efficiency. [ABSTRACT FROM AUTHOR]

Dam leakage is a major problem in earth-filled reservoir dams. The present research is aimed at detecting the seepage zones in an earth-filled reservoir dam in the vicinity of Sarobi village, North Waziristan, Pakistan. The objective was achieved by integrating geological, geotechnical, and geophysical datasets. Geological survey was carried out in the area to identify the surface exposures. Geotechnical data involved was used to estimation of permeability and Lugeon values to identify network of joints/fractures whereas electrical resistivity tomography (ERT) technique (utilizing Wenner-Schlumberger configuration) was applied for the identification of the leakage zones. Geological data revealed highly deformed alluvium towards the right abutment underlain by compressed shale and highly fractured limestone beds. Geotechnical data indicated high permeability, Lugeon values, and concentration of sand and gravel towards the right abutment whereas low permeability, Lugeon values, and higher concentration of silt and clay were observed towards the left abutment. ERT data identified a conductive zone embedded between impermeable lithologies having resistivity between 10 and 60 Ω·m. This conductive zone was observed in parallel profiles acquired in upstream, dam crest, and downstream parts of the dam. The integration of all the datasets revealed a network of joints that are interconnected and provide a path for water at the upstream side to pass through right abutment of dam and leak towards the downstream. [ABSTRACT FROM AUTHOR]

Herein, a kind of three-dimensional hollow Mg-Ca-Al hydrotalcite-like compounds (HTLCs) microsphere was prepared by self-assembly of hydrotalcite-like nanosheets. Mg-Ca-Al HTLCs microsphere (MS) has large specific surface area and large pore size, and the modification of KF·2H2O increases numerous alkaline active sites on the surface of the catalyst. The prepared catalyst has excellent catalytic effect for the production of biodiesel by transesterification. Under the optimal conditions of the catalyst addition amount which accounts for 2% of the weight of oil, the biodiesel yield of the best catalyst is as high as 92% within 30 minutes. This article also provides a paradigm of a rational structural design for regulating the morphology of HTLCs. [ABSTRACT FROM AUTHOR]

Carbon-based nanomaterials are contemporary and are outpacing the technology platform. Graphene quantum dots (GQDs) had a significant impact on the subject of bioengineering, pharmaceuticals, biomedicine, biosensors, fuel, energy, etc. Depending on how quickly this field is developing, it is important to recognize the new difficulties that GQDs have to overcome. This is incredibly significant because many novel applications and innovations that have made GQD synthesis easier recently have not been systematically evaluated in prior studies. Their ability to combine the benefits of quantum dots, sp2 carbon materials (large specific surface area), and have rich functional groups at the edge makes them special. The naturally occurring inert carbon helps to stabilize chemical and physical characteristics and makes significant advancements in the creation of benchmark photocatalysts. Moreover, current challenges and potential of these rapidly developing GQDs are emphasized. The future of GQD research is limitless, according to the assessment in this review, notably if future research focuses on simplicity of purification and ecofriendly synthesis. This feature article offers a realistic summary on recent developments in the synthesis, characteristics, and uses of GQDs. Frequent review articles focusing on the progress of GQDs for specific applications are published but a thorough review article on GQDs for their numerous uses has not yet been published. The recent trends of scientific research based on new optical biosensing applications, including the comprehensive applications of different zero-dimensional nanomaterials, specially GQDs are discussed in this study. [ABSTRACT FROM AUTHOR]

Magnetic nanobiochar (MNBC) is a sort of nanobiochar that has been enhanced with magnetic qualities. MNBC is made from a variety of feedstocks, including wood chips, agricultural waste, municipal sludge, animal manure, and other organic waste. These feedstocks are pyrolyzed at various temperatures to produce biochar, which is then mixed with magnetic precursors to create MNBC. Crystallinity, high porosity, specific surface area, and great catalytic activity are a few of the dynamic properties of MNBC. The major purpose of this review paper is to characterize MNBC, using the various biochar synthesis methods and how bulk biochar is converted into MNBC with their high-value applications discussed here. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2), the second most thoroughly investigated two-dimensional material after graphene, has attracted considerable interest in energy storage applications owing to its exceptional qualities, including its unique crystal structure, low electronegativity, and high specific capacity. In this study, we showed that a simple ball-milling procedure causes significant improvement in the capacitive properties of the bulk MoS2 (BL-MoS2). We characterized the material before and after the milling process using X-ray diffraction (XRD) and a BET surface area analyzer to find the material's structural, crystalline features, and surface area, respectively. We prepared electrodes of BL-MoS2 and ball-milled MoS2 (BM-MoS2) for electrochemical investigation. The charge storage characteristics were examined using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The BM-MoS2 and BL-MoS2 have a specific capacitance of 114 F/g and 96 F/g, respectively. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2), the second most thoroughly investigated two-dimensional material after graphene, has attracted considerable interest in energy storage applications owing to its exceptional qualities, including its unique crystal structure, low electronegativity, and high specific capacity. In this study, we showed that a simple ball-milling procedure causes significant improvement in the capacitive properties of the bulk MoS2 (BL-MoS2). We characterized the material before and after the milling process using X-ray diffraction (XRD) and a BET surface area analyzer to find the material's structural, crystalline features, and surface area, respectively. We prepared electrodes of BL-MoS2 and ball-milled MoS2 (BM-MoS2) for electrochemical investigation. The charge storage characteristics were examined using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The BM-MoS2 and BL-MoS2 have a specific capacitance of 114 F/g and 96 F/g, respectively. [ABSTRACT FROM AUTHOR]

Rayleigh-Taylor instability (RTI) is analyzed theoretically by Taylor, and 2-dimensional experimental results are obtained by Lewis in 1950. Over the 72 years, several experiments and theories are developed with the shock-driven Ritchmyer-Meshkov instability (RMI) and the shear-driven Kelvin-Helmholtz instability (KHI). Here, we emphasize the single-mode Rayleigh-Taylor instability (RTI) mixing simulation with a surface area in 3 dimensions. The simulation uses concentration equations and nonzero transport. We observed chaotic interface behavior even for this single-mode simulation, in the sense that the interface appears to have an area proportional to Δ x − 1 , with respect to its mesh (non)convergence (i.e., rate of divergence) properties. [ABSTRACT FROM AUTHOR]

Ozone and byproducts of ozone‐initiated reactions are among the primary pollutants in aircraft cabins. However, investigations of the spatial distribution and reaction mechanisms of these pollutants are insufficient. This study established a computational fluid dynamics‐based model to evaluate ozone and byproduct distribution, considering ozone reactions in air, adsorption onto surfaces, and byproduct desorption from surfaces. The model was implemented in an authentic single‐aisle aircraft cabin and validated by measurements recorded during the aircraft cruise phase. Ozone concentrations in the supply air‐dominated area were approximately 50% higher than that in the passenger breathing zone, suggesting that human surfaces represent a significant ozone sink. The deposition velocity onto human bodies was 21.83 m/h, surpassing 3.97 m/h on other cabin interior surface areas. Our model provides a mechanistic tool to analyze ozone and byproduct concentration distributions, which would be useful for assessing passenger health risks and for developing strategies for healthier aircraft cabin environments. [ABSTRACT FROM AUTHOR]

Moisture sorption isotherms of five sweet cherry cultivars (Prunus avium L.) at three temperatures of 30°C, 40°C, and 50°C, and water activity range of 0.057–0.898 were determined using the static gravimetric method. The sorption isotherms of all cultivars decreased with increasing temperature, and they all exhibited type II behavior according to the classification of IUPAC (International Union of Pure and Applied Chemistry). The isosteric heat of sorption, differential entropy, spreading pressure, and water surface area were determined, and the energy associated with the sorption processes was defined. The curves were fitted to GAB, PELEG, and ENDERBY models, and the GAB model gave the best fit for the whole set of data. The enthalpy–entropy compensation proved that the process occurs spontaneously and is fully controlled the enthalpy. The spreading pressure value varied with temperature in all sweet cherry cultivars in both the desorption and adsorption processes. The average surface area varied from 78.05 to 214.02 m2/g for desorption and from 49.0 to 204.4 m2/g for adsorption from 30 to 50°C. [ABSTRACT FROM AUTHOR]

In this study, the relationship between four expansion indices and the expansion potential of gypsum rock was studied; on this basis, a criterion for judging expansion potential is established for gypsum rock. The results show that the free expansion rate is unsuitable for grading gypsum rocks' expansion potential. Setting the gypsum rock in the Wuzhishan tunnel as the research subject, the ultimate expansion rate is 24.28% on the 7th day and 34.08% on the 30th day; the ultimate expansion rate on the 7th day of the indoor rock sample can be estimated by the fitting formula on the 30th day, the ultimate expansion force is 304.51 kPa, and the BET-specific surface area is 6.31 m2/g. The ultimate expansion ratio and BET-specific surface area have an excellent linear relationship with the ultimate expansion force. Setting the ultimate expansion force, ultimate expansion ratio and BET-specific surface area as the standard, the criterion for judging the expansion potential of gypsum rock is determined, which is more convenient and accurate than existing standards. The standard in this paper can predict the potential disasters that may occur in underground engineering. [ABSTRACT FROM AUTHOR]

Summary: Polyamide‐66 (PA‐66) is categorized as a highly positive‐charged triboelectric film in the fabrication of triboelectric nanogenerators (TENGs). Furthermore, the surface area of triboelectric film is critical in TENG production. With a simple, cost‐effective, and scalable technique, this study represents a paradigm shift in the manufacture of high surface area PA‐66 triboelectric films. The fabricated PA‐66 film was superficially modified and provided a high surface area to result in enhanced charge generation. The fabricated film could harvest mechanical energy in various TENG operational modes such as vertical contact and lateral sliding modes. Various TENGs were fabricated in this work to demonstrate the different operation modes on the prepared film and its efficiency. The TENGs were utilized to harvest mechanical energy from wind and vehicle motion and track real‐time vehicle acceleration. [ABSTRACT FROM AUTHOR]

Herein, porous Co3O4 nanoneedle arrays were synthesized on nickel (Ni) foam (Co3O4 NNs/NF) by one-step hydrothermal method. Some electrochemical methods were used to investigate its nonenzymatic glucose sensing performance in alkaline solution. The results show that the sensitivity of Co3O4 NNs/NF electrode to glucose is 4570 μA mM-1 cm-2. The linear range is 1 μM-0.337 mM, and the detection limit is 0.91 μM (S/N = 3). It also displays good selectivity and repeatability for glucose. The good electrochemical sensing performance of Co3O4 NNs/NF based sensor for glucose can be attributed to interconnected porous structure and large specific surface area of Co3O4. [ABSTRACT FROM AUTHOR]

Indoor air pollution associated with biomass combustion for cooking remains a significant environmental health challenge in rural regions of sub‐Saharan Africa; however, routine monitoring of woodsmoke aerosol concentrations continues to remain sparse. There is a paucity of field data on concentrations of combustion‐generated ultrafine particles, which efficiently deposit in the human respiratory system, in such environments. Field measurements of ultrafine and fine woodsmoke aerosol (diameter range: 10–2500 nm) with field‐portable diffusion chargers were conducted across nine wood‐burning kitchens in Nandi County, Kenya. High time‐resolution measurements (1 Hz) revealed that indoor particle number (PN) and particle surface area (PSA) concentrations of ultrafine and fine woodsmoke aerosol are strongly temporally variant, reach exceedingly high levels (PN > 106/cm3; PSA > 104 μm2/cm3) that are seldom observed in non‐biomass burning environments, are influenced by kitchen architectural features, and are moderately to poorly correlated with carbon monoxide concentrations. In five kitchens, PN concentrations remained above 105/cm3 for more than half of the day due to frequent cooking episodes. Indoor/outdoor ratios of PN and PSA concentrations were greater than 10 in most kitchens and exceeded 100 in several kitchens. Notably, the use of metal chimneys significantly reduced indoor PN and PSA concentrations. [ABSTRACT FROM AUTHOR]

A contact model for rough surfaces based on the fractal theory is proposed in the present work. Firstly, the deformation of the material is divided into four stages: elastic deformation, the first elastoplastic deformation, the second elastoplastic deformation, and full plastic deformation. And the variation of material hardness is considered when analyzing the contact characteristics of a single asperity within the first and second elastoplastic deformation stages. Secondly, the size distribution function of contact spots at different frequency levels is derived. And the expressions of asperity critical frequency levels are rederived. Lastly, the feasibility and credibility of the proposed model are verified by comparison with other contact models and experimental data. The results show that when the variation of the material hardness is considered, the contact area of a single asperity in the first elastoplastic deformation stage becomes larger, while the contact area of a single asperity in the second elastoplastic deformation stage becomes smaller. Moreover, the critical asperity frequency levels of the rough surface are not constant, but the variables are related to the total real contact area of the rough surface and decrease as the real contact area increases. The proposed model is a modification and improvement of the existing fractal contact models, which can lead to a more accurate relationship between the contact load and the total real contact area of the rough surface. [ABSTRACT FROM AUTHOR]

In order to solve the design and regulation problems of graded porous scaffolds, the triply periodic minimal surface (TPMS) that based on implicit function was taken as the pore unit for constructing the porous scaffolds. And the TPMS structure was controlled by selecting different types of TPMS and defining the distance function. The transition of different structures of TPMS was performed by the weight fusion method. And the dual contouring (DC) algorithm and octree algorithm were used to divide the solid model of the defect bone into hexahedral elements to determine the target assembly spatial. Through the coordinate transformation of the isoparametric element method, the pore units were mapped into the hexahedral elements to construct porous structure. Finally, a Boolean operation was used to obtain a bone scaffold model with porous structure. The examples showed that the gradient model of various irregular pores could be constructed, and the pore size, porosity, and specific surface area of porous scaffolds could be controlled by adjusting the deformation, distribution, volume of the hexahedral elements, and the structure of the TPMS pore units, which provides a feasible method for the design and regulation of heterogeneous porous scaffolds. [ABSTRACT FROM AUTHOR]

In this review, we summarized the state-of-the-art progress on the ethanol performance of NiO by means of morphology, doping, loading noble metal particles, and forming heterojunctions. We first introduced the effect of modulating NiO morphology on ethanol performance that has been reported in recent years. The morphology with large specific surface area and high porosity was considered to be the one that can bring high gas response. Then, we discussed the enhanced effect of the doping of metal cations and noble metal particle loading on the ethanol-sensitive properties of NiO. Doping ions increased the ground-state resistance and increased the oxygen defect concentration of NiO. The effects of noble metal particles on the performance of NiO included chemical sensitization and electronic sensitization. Finally, the related contents of NiO forming complexes with metal oxides and bimetallic oxides were discussed. In this section, the specific improvement mechanism was discussed first, and then, the related work of researchers in recent years was summarized. At the same time, we presented a reasonable outlook for NiO-based ethanol sensors, imagining future directions. [ABSTRACT FROM AUTHOR]

Motivated by Lutwak et al.'s L p -dual curvature measures, we introduce the concept of L p -curvature measures. This new L p -curvature measure is an extension of the classical surface area measure, L p -surface area measure, and curvature measure. In this paper, we first prove some properties of the L p -curvature measure. Next, using the L p -curvature measure, we define the L p , q -mixed volume which includes L p -mixed volume as the special cases. Further, the Minkowski-type inequality related L p , q -mixed volume and the uniqueness of the solution for the L p , q - Minkowski problem are obtained. Finally, we propose several problems that need to be studied further. [ABSTRACT FROM AUTHOR]

The application of robots reduces repetitive and dangerous tasks for humans, especially the spraying robot, because many spraying materials are corrosive, toxic, and harmful. This paper designs the motion trajectory planning of the material spraying service robot. With the increasing demand for technology, there are strict requirements for the uniformity and thickness of spraying. In view of this, this paper proposes an algorithm for modeling kinematics using a joint screw and optimizes the modeling algorithm using particle swarm optimization. This makes the industrial spraying robot more intelligent and more capable of completing high-standard tasks. The experimental results in this paper show that when the spraying radii on the large-curvature cone surface are 44.5 and 49.5 mm, respectively, the coating distribution in the intersection area of the curved surfaces can be well controlled, and the optimized algorithm can better plan the path of the spraying robot. [ABSTRACT FROM AUTHOR]

Compressive strength of alkali-activated slag (AAS) concrete is influenced by multi-factors in a nonlinear way. Both artificial neural network (ANN) and alternating conditional expectation (ACE) models of 3-day (3 d) and 28-day (28 d) compressive strength of AAS were established in this study by using the data reported in related literature, where alkali concentration of activator (Na2O%), modulus of activator (Ms), water/binder ratio (W/B), surface area of slag (SA), and basicity index of slag (Kb) were taken as input parameters. The models were employed later to predict 3 d and 28 d compressive strength of AAS concretes, respectively, and the results were validated by experimental work. The results show that both the ANN and the ACE models had adequate accuracy, no matter 3 d or 28 d compressive strength was considered. Compared to the 3 d compressive strength, due to data scattering that increased with the increase of data size, both the models did not yield a higher accuracy in the case of 28 d strength. However, also due to the increase in data size, both the models were more feasible to implement 28 d strength prediction as a result of sufficient learning and training during modeling. In addition, based on ACE analysis, the weight-influencing compressive strength of AAS decreased in a sequence of Na2O% > Ms > W/B > Kb > SA. If data size was sufficiently large, it was more suitable to establish an ANN model for compressive strength prediction of AAS concretes. Otherwise, ACE could be considered as an alternative to yield an acceptable result. [ABSTRACT FROM AUTHOR]

This study was focused on the synthesis of activated carbon from a waste tire and the enhancement of its specific area by a demineralization technique that can be used for the removal of methylene blue dye (MB). Maximum MB removal (89.41%) was attained at an impregnation ratio value of 0. A maximum yield (42.65%) was found at 48 h. Waste tire-based activated carbon (WTAC)'s ability to remove MB was increased by large values up to an impregnation time of 24 h. WTAC has a maximum MB removal of 90.13% at 4 M of KOH. The sample had a surface area of 53 m2/g. This sample was demineralized by using NaOH and H2SO4 in a 1 : 1 ratio, and the surface area was enhanced to 257 m2/g. In the demineralization process, a massive decrement of metals from the waste was seen; for each metal, namely, Zn2+, Al3+, Ca2+, and Mg2+, 43.79%, 32.45%, 27.95%, and 6.843% reductions were achieved, respectively. After this process, the maximum removal of MB was found at 1.2 g adsorbent dosage, 120 min, pH 8, the temperature of 20°C, and an initial dye concentration of 10 mg/L. The adsorption mechanism revealed that the process of adsorption happens at a specific site of homogeneous adsorption on the surface of the adsorbent. The kinetics study showed that the adsorption process of the dye is mainly affected by the chemical reaction. [ABSTRACT FROM AUTHOR]

Summary: In this paper, Al‐doped manganese oxide with presetting sodium‐ion (NaxMnyAlzO2) is synthesized by a facile coprecipitation method and combines with Na3V2(PO4)3 cathode active materials for sodium‐ion battery in order to optimize the electrochemical performances. During the coprecipitation, a stable NaxMnyAlzO2 polynary metal oxide with Mn and Al molar ratio to 3:1 shows a special micromorphology similar to that of reed leaves, which makes it have a more ideal electrochemical specific surface area and ample mass transfer channels for rapid sodium‐ion insertion and desorption. Electrochemical test indicates that reed‐leaves like NaxMnyAlzO2 polynary metal oxides as active material for sodium‐ion capacitor exhibit a very excellent reversibility and low electrochemical (Rct = 434 Ω) and concentration polarization (DNa+ = 2.2728 × 10−11 cm2 s−1). Specific discharge capacity can achieve to 73.76 F g−1 at 100 mA g−1 current density corresponding to 368.8 m2 g−1 electrochemical specific surface area. After 200 cycles, the capacity retention rate can be maintained at 81.81%. In addition, reed‐leaves like NaxMnyAlzO2 polynary metal oxide playing a good depolarization role combined with Na3V2(PO4)3 active materials in the mass ratio to 7:3 can bring about the most excellent electrochemical performances. [ABSTRACT FROM AUTHOR]

The shape of the hydraulic flushing hole is an important basis to determine the effective pumping radius. In the design and evaluation of the drilling hole, it is usually equivalent to a cylinder. However, the formation of the shape of the hole is affected by the gravity of coal and rock bulk, the friction of coal and rock, water force, stress, and other factors, so the scientific nature that is equivalent to a cylinder remains to be discussed. In this paper, based on the analysis of the whole process of hydraulic flushing and the formation of the pore shape, gravity, friction, water force, and ground stress of coal and rock bulk are selected as important factors affecting the pore shape, and the parallel Bergmark-Roos equation and PKN model are introduced to establish the BR-PKN equation of the pore shape of hydraulic flushing. MATLAB is used to reproduce the shape of the hydraulic flushing hole, which is a kind of ellipsoid with three different axes. In order to verify the accuracy of the hole shape, the YZD18.5 video imaging logging tool for mine lateral resistivity is used to collect and analyze the shape data of the hydraulic flushing hole, and the hole section is drawn, which is basically consistent with the theoretical derivation of the hydraulic flushing hole shape. COMSOL is used to simulate the hydraulic flushing equivalent of the ellipsoid hole compared with the cylinder hole under the same coal output and extraction time of 90 days. The extraction radius, desorption surface area, and effective extraction volume are 0.95, 0.79, and 1.14 times, respectively, providing a basis for the optimal design of hydraulic flushing. [ABSTRACT FROM AUTHOR]

To solve the problem of liquid-phase synthesis of nano-ZnO, a photocatalytic performance study was proposed. In this study, the microwave homogeneous precipitation method was used to add different types and amounts of surfactants. The synthesis of nano-zinc oxide was controlled by changing the reaction system conditions. The photocatalytic properties of nano-zinc oxide for degrading three water-soluble dyes were preliminarily studied and discussed. The results show that the photocatalytic performance of nano-ZnO is closely related to its size, morphology, specific surface area, and even crystallographic direction. [ABSTRACT FROM AUTHOR]

A response surface was employed to establish a statistical model for influencing factors and response targets to study the influence of laser cladding process parameters on the quality of Co-based WC composite coating and reduce defects in the cladding layer. Analysis showed that the cladding step and laser power were the most significant factors affecting the coating's porosity area and surface flatness. Increasing the amount of WC and the laser power significantly enhanced the hardness of the coating. The validation experiments under optimized conditions showed that the predicted value of the model was in good agreement with the actual value, and the average error was less than 6%. This study presents the preparation of Co-based WC ceramic composite coating by laser cladding and the optimization of process parameters. [ABSTRACT FROM AUTHOR]

A low-cost goethite and manganese acetate were used to prepare a MnOx/α-Fe2O3 composite catalyst by simple impregnation method for novel high-efficiency selective catalytic reduction (SCR) of NO with NH3, and its denitration performance of composite catalyst under different conditions was investigated in a thermal fixed-bed catalytic reaction system. The results showed that MnOx/α-Fe2O3 with Mn/Fe molar ratio of 0.1 and calcination temperature of 400 °C had the best low-temperature catalytic activity and wider reaction temperature window compared with α-Fe2O3. It achieved over 90% NO conversion efficiency with a space velocity of 72,000 h−1 at 200~350 °C and possessed a good resistance of H2O and SO2. Characterization by XRD, BET, H2-TPR, and NH3-TPD revealed that the main reason for the high catalytic activity of MnOx(0.1)/α-Fe2O3(400) was that the addition of Mn changed phase types of catalyst and valence composition of Fe, resulting in a larger specific surface area, more acidic sites, and higher redox performance. [ABSTRACT FROM AUTHOR]

A low-cost goethite and manganese acetate were used to prepare a MnOx/α-Fe2O3 composite catalyst by simple impregnation method for novel high-efficiency selective catalytic reduction (SCR) of NO with NH3, and its denitration performance of composite catalyst under different conditions was investigated in a thermal fixed-bed catalytic reaction system. The results showed that MnOx/α-Fe2O3 with Mn/Fe molar ratio of 0.1 and calcination temperature of 400 °C had the best low-temperature catalytic activity and wider reaction temperature window compared with α-Fe2O3. It achieved over 90% NO conversion efficiency with a space velocity of 72,000 h−1 at 200~350 °C and possessed a good resistance of H2O and SO2. Characterization by XRD, BET, H2-TPR, and NH3-TPD revealed that the main reason for the high catalytic activity of MnOx(0.1)/α-Fe2O3(400) was that the addition of Mn changed phase types of catalyst and valence composition of Fe, resulting in a larger specific surface area, more acidic sites, and higher redox performance. [ABSTRACT FROM AUTHOR]

Electrochemical DNA sensors based on nanocomposite materials of polyaniline nanowires (PANi NWs) have been published in the literature. However, it is interesting that there are very few research studies related to the development of electrochemical DNA sensors based on PANi NWs individually. In this study, PANi NWs were synthesized site-specifically on a Pt microelectrode with only 0.785 mm2 area using an electropolymerization procedure. The electrosynthesis allows direct deposition of PANi NWs onto the Pt microelectrode in a rapid and cost-effective way. The good properties of PANi NWs including uniform size, uniform distribution throughout the Pt working electrode, and H2SO4 doping which improved the conductivity of the PANi material were obtained. Especially, the electrochemically effective surface area of the PANi NW-based Pt microelectrode determined in this work is nearly 19 times larger than that of the Pt working electrode. The PANi NW layer with large electrochemically effective surface area and high biocompatibility is consistent with the application in electrochemical DNA sensors. The fabricated DNA sensors show advantages such as simple fabrication, direct detection, high sensitivity (with the detection limit of 2.48 × 10−14 M), good specificity, and low sample volume requirement. This study also contributes to confirm the role of PANi NWs in DNA probe immobilization as well as in electrochemical signal transmission in the development of electrochemical DNA sensors. [ABSTRACT FROM AUTHOR]

Kaolinite, a clay mineral, is an important industrial mineral which was gainfully utilized with several industrial significances. Towards mineral beneficiation, the present study aimed to investigate the effect of calcination temperature on the pozzolanic activity and specific surface area of Ethiopian kaolinite (Ek). The raw Ek and calcined Ek were characterized using different sophisticated techniques, such as XRD, FTIR, DSC, TGA, dynamic light scattering, electrophoretic light scattering, and SEM analysis. The pozzolanic activity and specific surface area of Ek particles were ascertained using Chapelle's and Brunauer–Emmett–Teller methods, respectively, with some modifications. The results revealed that the calcination temperature had a great influence on pozzolanic activity and specific surface area of Ek. It was observed that the pozzolanic activity linearly increased with calcination temperature until 700°C and showed a maximal value of 1235 mg Ca(OH)2 g−1. On the other hand, beyond 700oC, the pozzolanic activity was inferred to be declined to 445 mg Ca(OH)2 g−1 at 1000°C due to agglomeration of calcined kaolinite (metakaolinite) and formation of spinel phase. A similar phenomenon was observed for specific surface area which increased with temperature until 700°C to exhibit the maximal values of 47.794 m2·g−1. Further, the investigation on zeta potential analysis showed that the magnitude value of the metakaolinite was observed to be less than the zeta potential value of the raw kaolinite, which indicated that the flocculation tendency of metakaolinite was greater than the kaolinite flocculation affinity in water. [ABSTRACT FROM AUTHOR]

Summary: The microporous carbon with large surface area is widely used in supercapacitors. However, the sluggish ion transport kinetics drastically hampers the practical application. Herein, an efficient in‐situ expansion strategy for the preparation of hierarchically structured mesoporous carbon is developed by the pyrolysis of sodium lignosulfonate with HCOOK. Various techniques including in‐situ methods are employed and the formation mechanism of the hierarchical mesoporous structure is thus clarified. The grain refinement, crystal rearrangement and in‐situ expansion enable the formation of the unique porous carbon with a high mesoporous volume, an interconnected and hierarchical porous structure and a large ion‐accessible specific surface area. The specific capacitance and capacitance retention of the obtained sample reach 436 F g−1 (1 A g−1) and 64% at 100 A g−1 in the aqueous electrolyte in a three‐electrode system. Moreover, the obtained sample also shows a high energy density of 41.2 Wh kg−1 in a two‐electrode system using ionic liquid as electrolyte. The novel in‐situ route can be extended to the synthesis of other biomass‐based carbon materials for electrochemical applications. [ABSTRACT FROM AUTHOR]

To investigate the influences of the chemical corrosion on the dynamic fracture mechanical properties and failure characteristics of marble, the dynamic fracture test for the notched semicircular bend (NSCB) marble specimens with different degrees of corrosion damage was conducted using a split Hopkinson pressure bar. The results show that both the porosity and corrosion damage variable Dc characterized by porosity increase as corrosion time T increases. The dynamic fracture toughness decreases linearly from 5.22 to 2.15 MPa m1/2 as Dc increases from 0 to 4.42%. This is because the corrosion damage done to interior structure leads to a reduction of cohesion and internal friction angle inside the specimen. In the Dc range of 0–4.42%, the fractal dimension of the main crack propagation path increases from 1.47 to 1.59, by an increase rate of 8.16%. Both the joint roughness coefficient and the actual area of the fracture surface increase as Dc increases. Due to the degradation of the connected force between the rock particles inside the specimen, there is an obvious decrease in the fracture energy per unit fracture surface from 0.94 to 0.38 J cm−2, with a decrease rate of 59.39%. With T increases, the contents of CaO, MgO, and Al2O3 in specimen increase, indicating that the degree of corrosion damage increases. [ABSTRACT FROM AUTHOR]

Nanocrystalline spinel ferrite based compounds are technological driven materials with interesting potentials in photocatalysis for renewable energy generation, gas sensing for pollution control, magnetic drug delivery, rod antennas, storage media (high density) and supercapacitive materials, among others. Specific surface area of spinel ferrite based compounds contributes immensely to the application of this semiconductor in industrial domains. Experimental determination of specific surface area is laborious and costly and consumes appreciable time. Compositional substitutions in crystal structure effectively improve physical properties and enhance specific surface area through alteration of moment distribution between tetrahedral oxygen sites and octahedral coordination. With the aid of distorted lattice parameters due to compositional substitution and the spinel ferrite nanocrystallite size as model descriptors, this present work models the specific surface area of spinel ferrite nanomaterial through extreme learning machine (ELM) based intelligent modeling method. The developed sigmoid activation function-based ELM (S-ELM) model shows superior performance over genetic algorithm based support vector regression (GBSVR) and stepwise regression (STWR) models existing in the literature with performance improvement of 61.31% and 70.01%, respectively, using root mean square error performance metric. The significances of cobalt and lanthanum compositional substitution on the specific surface area of spinel ferrite nanomaterials were investigated using S-ELM model. Ease of implementation of S-ELM model as compared with the existing GBSVR model, coupled with the demonstrated improved performance and persistent closeness of its predictions with the experimental values, would be highly meritorious for quick and precise characterization of specific surface area of spinel ferrite nanomaterials for various desired applications. [ABSTRACT FROM AUTHOR]

As a result of developing technology and scientific studies, employing dam tailings as critical raw material and vital economic reserve has become widespread recently. Employing dam tailings as a main ingredient of CPB (cemented paste backfill) can offer benefits to mining operations. This study deals with the use of dam tailings in CPB, considering the mechanical and geotechnical aspects. CPB was prepared at fixed solid and cement contents (72%, and 5%, respectively) and tested for different cure ages varying from 3 to 56 days. The results disclosed that the strength of filling increased over time, with the exception of 56-day cured CPB having high sulfur minerals where strength decreased sharply. The reasons behind these strength surges could be clarified by CPB's basicity, which quickens the hydration of cement. Voids between tailings grains are also occupied by hydration products, resulting in the high strengths. Due to the fact that higher sulfate contents can cause lower pH values within CPB, this is one of the factors that should be considered for the backfill's strength performance. The cement tends to increase the backfill's pH in short term, but pH of long-term cured backfills decreases because of dam tailings which is inclined to acid formations and erosions. This is a sign that the deformation properties of CPB are deteriorated. Depending on curing time, CPB's water content and void ratio decrease, but their surface areas increase. The resulting data will endow to better apprehend the effects of dam tailings on CPB quality integrating cost and quality. [ABSTRACT FROM AUTHOR]

Summary: Sustainable biomass‐derived carbons in powdery forms have shown to be high‐performance capacitive electrode materials for application in supercapacitors (SCs) due to their large specific surface area, distinct porous structure, and low cost; however, their practical applications are being largely hampered due to their powdery status‐related issues including tedious electrode assembly process and insufficient capacitance and cycling stability. Herein, we develop a porous carbon membrane, termed as PECM, by direct carbonization of Pleurotus eryngii (PE) using KOH as activator. The as‐fabricated PECM features a hierarchically nanostructure with high porosity, large specific surface area, and excellent electrolyte wettability, which cannot only afford a large usable active area for the interfacial adsorption of electrolyte ions but also supply fast diffusion pathways for electrolyte ions. Moreover, the as‐fabricated PECM is doped with N and also has large amounts of O, S, and P‐containing functional groups, which would be expected to contribute additional pseudocapacitance. More importantly, the as‐fabricated PECM has excellent mechanical performance and can be directly used to assembly an aqueous symmetric SC device. Attributing to the above structural merits of PECM, the two‐electrode symmetric SC assembled using two identical PECM‐800 electrodes (~20 mg cm−2 for each electrode), exhibits excellent electrochemical performance with ultrahigh areal capacitance (4.6 F cm−2 at 10 mA cm−2), excellent long‐term cycling stability (113% capacitance retention after 20 000 cycles), and superior energy densities of 0.24 to 0.09 mWh cm−2 at power densities of 5.20 to 51.9 mW cm−2. This work offers a new insight on employing biomass to prepare value‐added and practically applicable carbon materials for the application in SCs. [ABSTRACT FROM AUTHOR]

To improve the aging resistance of bioasphalt and explore the impact of organic nano calcium carbonate (CaCO3) on the aging resistance of bioasphalt, the thin-film oven test (TFOT), basic property test, rheological test, four components test, and infrared spectrum test were used to study the bioasphalt with different organic nano-CaCO3 contents. The results show that the addition of organic nano-CaCO3 increases the residual penetration, residual ductility, and residual softening point of bioasphalt. Within the range of test dosage, the greater the dosage, the more significant the effect is. With the increase of organic nano-CaCO3 content, the complex modulus aging index (GAI) of bioasphalt gradually decreases, and the colloidal instability index (IC) gradually decreases. When the content is 6%, the GAI of organic nano-CaCO3 modified bioasphalt is less than that of matrix asphalt. The nanoscale super large specific surface area of organic nano-CaCO3 has an adsorption effect on the light components in bioasphalt, which slows down the volatilization loss of light components and the oxidation process of asphalt. The addition of organic nano-CaCO3 helps to reduce the change rate of the carbonyl index and sulfoxide index. [ABSTRACT FROM AUTHOR]

Summary: Heteroatom‐doped porous carbon materials have great potential for both capacitive energy storage and gas sorption applications. This article reports the synthesis of highly porous sulfur‐doped carbon from thiophene using an in situ self‐doping strategy followed by KOH activation. A series of highly porous sulfur‐containing carbon materials with high surface area and pore volume were prepared through variation of activation temperature from 600°C to 900°C and applied as supercapacitor electrodes in alkaline as well as neutral electrolyte and also as adsorbent for CO2, H2 adsorption. The material prepared at 800°C presented the highest electrochemical performance with a specific capacitance of 300 F g−1 at 1 A g−1 in 6 M KOH because of its high surface area and pore volume. The presence of oxidized sulfur functionality, high surface area, and micro‐mesoporous structure were the responsible factors for enhanced storage of gases like CO2 and H2. The functionalized carbon showed a good H2 uptake value of 2.8 wt% under 1 bar pressure at 77 K. CO2 uptake capacities were found to be 5.6 and 3.3 mmol g−1 at 1 bar pressure under the temperature of 273 and 298 K, respectively with a good CO2/N2 selectivity of 14.36 and CO2/CH4 selectivity of 2.53. This report presents a promising porous sulfur‐doped carbon material for cost‐effective and efficient gas adsorption and energy storage systems. [ABSTRACT FROM AUTHOR]

Automated valet parking (AVP) has attracted much attention as the entry point to autonomous driving. In an indoor environment, high-precision positioning systems are essential for AVP. Ultra-wideband (UWB) is one of the most widely adopted techniques. However, the base station placement significantly influences the system's positioning accuracy, especially for the irregular architecture of underground parking lots. This article proposes a three-stage practical and economical layout planning approach for UWB base stations, including determining the deployment strategy and layout parameters and comprehensive adjustment and scheme verification. The approach considers regional differentiation accuracy requirements for AVP, such as ramp area, surface fluctuation area, and narrow area. The adopted positioning method of a UWB system is the time difference of arrival (TDOA), and the evaluation index of positioning accuracy is the horizontal dilution of precision (HDOP). Through experimental tests in an actual parking lot, the proposed approach is confirmed to ensure stability and economy with fewer UWB base stations and can meet the positioning accuracy requirements of AVP. [ABSTRACT FROM AUTHOR]

Summary: A conductive agent, which is typically added to overcome the low electronic conductivity of Ni‐rich‐layered oxides, plays a significant role toward performance improvement of layered‐oxide‐based cathodes. Herein, the effects of the specific surface area, powder density, and aggregation characteristics of a conductive agent on Li1.03Ni0.88Co0.08Mn0.04O2 (Ni‐rich NCM) cathode performance are studied. The aggregation of conductive agents is disadvantageous for the distribution/arrangement of active materials and leads to polarization on the electrode surface. The specific surface area, which is proportional to porosity, contributes to the acceleration of electrode kinetics. However, the application of high pressure that makes a conductive agent excessively dense can degrade kinetic performance in the electrode. The low powder density of a conductive agent results in a nonhomogeneous electrode morphology and inhibits the mobility of Li ions in the electrolyte because of the segregation of the active materials from conductive agents. Powder density has a dominant effect on electrochemical performance. Even if the same active material is used, cycle retention is improved by 15%. In conclusion, the larger the specific surface area, the lower the powder density. Moreover, the less well‐aggregated the conductive agent, the higher the performance of the Ni‐rich NCM cathodes. [ABSTRACT FROM AUTHOR]

Summary: Despite the commercialization and tremendous attention of the Ni‐rich LiNiCoMnO2 cathode due to high energy and working voltage, there are still hurdles to be improved. The conventional polycrystalline Ni‐rich LiNiCoMnO2 suffers from decays of specific capacity and energy during long‐term cycling. It originates from more deficiency of oxygen and microcracking, resulting in severe phase transition toward disordered rock salt phase. Herein, single‐crystalline Ni‐rich LiNi0.91Co0.06Mn0.03O2 is successfully prepared to overcome these inherent drawbacks of polycrystalline. Benefiting from reduced specific surface area and grain boundaries, single‐crystalline Ni‐rich LiNi0.91Co0.06Mn0.03O2 outperforms polycrystalline in all electrochemical performances. The single‐crystalline LiNi0.91Co0.06Mn0.03O2 exhibits not only superior cycle stability of 84.7% at 40°C after 100 cycles but also high‐capacity retention of 76.2% under 2 C via improving structural integrity. Therefore, this work reveals that single crystalline can be a breakthrough for stable and high electrochemical performances. [ABSTRACT FROM AUTHOR]

Summary: Highly graphitic nitrogen‐doped carbon nano‐onions (N‐CNO) have attracted much attention in the field of energy storage device applications. Herein, we have synthesized N‐CNO by a simple flame pyrolysis method for symmetric and asymmetric (ASC) supercapacitor devices. The nitrogen doping is performed in‐situ during the pyrolysis of pyrrole. The synthesized N‐CNO has a high surface area of 49 m2 g−1 with 4 at% nitrogen content. The structural properties have confirmed the formation of graphitic N‐CNO with highly ordered concentric graphene layers with proper lattice spacing. The fabricated symmetric and asymmetric devices have shown high specific capacitance and excellent energy‐power performance. Especially, the ASC device shows a specific capacitance value 205 F g−1 with a high energy density (60 Wh kg−1) and power density (5.5 kW kg−1), leading to an increase in the power density by 260% for a mere 60% decrease in the energy density. In addition, both the novel symmetric and asymmetric devices have shown excellent capacity retention of 96% to 98% over 5000 cycles. The demonstrated results show the superior electrochemical performance of the active material, which indicates that the N‐rich‐CNOs can be used as a novel anode material in energy storage devices with high energy density and high power performance. [ABSTRACT FROM AUTHOR]

Objective. To study the possible mechanism of ghrelin in heart failure and how it works. Method. In vitro results demonstrated that ghrelin alleviates cardiac function and reduces myocardial fibrosis in rats with heart failure. Moreover, ghrelin intervention increased PTEN expression level and reduced ERK, c-jun, and c-Fos expression level; in vivo experiments demonstrated that ghrelin intervention reduces mast memory expression and increases cardiomyocyte surface area, PTEN expression level, ERK, c-jun, c-Fos expression level, and cell surface area, while ERK blockade suppresses mast gene expression and reduces cell surface area. Results. In vitro experimental results prove that we have successfully constructed a rat model related to heart failure, and ghrelin can alleviate the heart function of heart failure rats and reduce myocardial fibrosis. In addition, ghrelin is closely related to the decrease of the expression levels of ERK, c-jun, and c-Fos, but it can also increase the expression of PTEN in the rat model; in vivo experiments proved that we successfully constructed an in vitro cardiac hypertrophy model, and the intervention of ghrelin would reduce the expression of hypertrophic memory and increase the surface area of cardiomyocytes, increase the expression level of PTEN, and reduce the expression levels of ERK, c-jun, and c-Fos, while the blockade of PTEN will increase the expression of hypertrophy genes and increase the cell surface area, while the blockade of ERK will increase the expression of hypertrophic genes, which in turn will make the cell surface area reducing. Conclusion. Ghrelin inhibits the phosphorylation and nuclear entry of ERK by activating PTEN, thereby controlling the transcription of hypertrophic genes, improving myocardial hypertrophy, and enhancing cardiac function. [ABSTRACT FROM AUTHOR]

There are various complex joints (fissures), laminae, and other soft structural surfaces in the roadway enclosure, and the existence of these soft structural surfaces seriously affects the stability of the roadway enclosure. In order to study the mechanical properties of the coal body and the development of joints during coal fracture, this paper establishes a three-dimensional model of the fracture structure of the coal body based on CT scanning and three-dimensional reconstruction technology. On this basis, a 3D numerical model of the equivalent nodal coal body is constructed, uniaxial compression simulation analysis is performed, and the joint evolution development law of the coal sample is studied by the built-in joint monitoring program of PFC3D. The results show that the larger the effective joint area and larger the joint size inside the coal sample, the smaller the compressive strength of the coal sample. The increase of joint size and joint surface area increased the ductility and stress-strain curve multipeak phenomenon of the coal sample to some extent. During the rupture of the coal sample, the changes of each phase of the statistical curve of joint number and the phases of the stress-strain curve of the coal sample are compatible. [ABSTRACT FROM AUTHOR]

While higher high specific surface area allows micro-supercapacitor (MSC) electrode materials to have improved performance, it also tends to make them less stable thermodynamically and microstructurally, which can easily deteriorate and seriously affects their service life. So here, we have chosen a crosslinked copolymer film structure as MSC electrodes. The pyrrole-thieno [3,4-b] thiophene (TbT) copolymer film (namely PPy-co-TbT) exhibits high specific capacity, which can reach 47.8 mF cm-2 (a specific volumetric capacitance of 23.9 F cm-3 and a specific gravimetric capacitance of 28.1 F g-1) at a current density of 0.1 mA cm-2 using LiCl/PVA gel electrolyte with ultra-long cycling stability (capacitance retention after 50 000 charge/discharge cycles is still higher than 93%, which is the leading level in MSCs). The electrochemical performance of this cross-linked copolymer is superior to that of the singlecomponent polymer, achieving a 1 + 1 > 2 effect. Both features of crosslinking and copolymerization have positive effects on microelectrodes requiring stable microstructures and high performance. The structurally stable crosslinked copolymer obtained by copolymerization design may become a durable material for next generation ultra-long-life, high-performance microsupercapacitor electrodes and will be widely developed. [ABSTRACT FROM AUTHOR]