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Hydroxyapatite (HAP) contains abundant defect sites and easily releases hydroxyl groups to produce new vacancies under calcination at high temperature. The highly dispersed VOx/HAP catalyst was prepared by an impregnation method using these defects as inducement. VOx species with different structures were analysed by XRD, XPS, H2‐TPR, Raman and UV–vis spectroscopy. At low calcination temperatures (500 °C and 600 °C), the V species are mainly V2O5 crystals. At high calcination temperatures (above 700 °C), VOx on the HAP surface fills these defect sites and strongly interacts with HAP to form Ca−O−V or P−O−V bands. These scattered defects improved the dispersion of V species. These highly dispersed VOx/HAP catalysts were used for oxidative dehydrogenation (ODH) of cyclohexane to cyclohexene. The highly dispersed VOx/HAP catalyst showed a high selectivity for cyclohexene, and the selectivity reached 48.2 % when the conversion of cyclohexane was 13.1 % at 410 °C. [ABSTRACT FROM AUTHOR]

Color filters play an important role in the quality of complementary metal–oxide–semiconductors and thin-film-transistor liquid-crystal displays. Although pigment nanoparticles have traditionally been used as color filter colorants, the use of molecular dyes for preparing high-quality color filters is an emerging strategy. However, few studies have investigated the relation between the structure of dyes and their color filter characteristics, such as solubility, and thermal stability and photostability. In this study, six phthalocyanine dyes with different branched substituents and central metals (zinc and copper) were developed. These dyes displayed high levels of solubility in propylene glycol monomethyl ether acetate (up to 40.8 wt%), high light transmission, and satisfactory thermal stability and photostability, indicating their potential application in color filters. They may provide a way to explore more molecular dyes for color filters with excellent dissolution properties. [Display omitted] • Six novel phthalocyanines have been synthesized by a transesterification process. • The solubility of the phthalocyanines in PGMEA has been improved. • The phthalocyanines have excellent transmission, thermal and photostability under industrial conditions. [ABSTRACT FROM AUTHOR]

In this paper, we use extensive empirical data sets from Shanghai 50ETF (SH50ETF) and SH50ETF options markets in China to study how regime-switching jump-diffusion models improve goodness of fit and option pricing performance. Firstly, the model parameters are estimated by using maximum likelihood estimation and the numerical analysis indicates that the regime-switching jump-diffusion models outperform a range of other models. Secondly, the analytical option pricing formulae are obtained via the fast Fourier transform and the empirical results using the proposed option pricing formulae are presented. Finally, we find that the calculated option prices are fairly consistent with the actual market prices. [ABSTRACT FROM AUTHOR]

[Display omitted] • A comprehensive analysis was conducted on the formation process of ridges from multiple perspectives. • Data processing was carried out using Python programming methods. • The shape function expression was obtained by fitting the contour data points of the ridge cross-section. • The intensity of soil disturbance was analyzed using regional statistical methods. • Technical support is provided for analysis of ridge forming. The Northwest of China is a typical production mode of rain-fed agriculture, which mostly adopts the whole film-mulching and double ridge–furrow technique to address the difficulty of surface water storage. However, the quality of ridge formation directly affects the water storage on both sides of the ridges, the reliability of plastic film mulching, and the crop growth. This study focused on the process of rotary tillage ridging, took different inclination angles and depths of ridger as variable factors, explored the influence of different operation parameters on the quality of ridge forming. The soil viscoelastic model was established in the study using the discrete element method. The changes in ridger resistance, ridge structure, and soil particle disturbance were analyzed in detailed, respectively. The results indicated that as the inclination angles and depths of ridger increased, the resistance of ridger also increased. The height of the ridges significantly influenced by the inclination angles and depths of ridger, and under the same inclination angles of ridger, the height of the ridges was directly proportional to the depth of ridger. Under different combinations of operational parameters, the height of the small ridges had good agreement with the ridging agronomy. As for the large ridges, when the depth of ridger was 100 mm and the inclination angles were 15°, 30°, and 45°, the working parameters met the agronomic requirements for ridge forming. In terms of soil disturbance, the soil located within a range of 30–90 mm from the surface was most susceptible to disturbance from the rotary tillage and the ridger, and the soil disturbance was stronger in the small ridges compared to the large ridges. The results of study contributed to a deeper understanding of the rotary tillage ridging process and provided insights into the factors influencing the quality of ridge forming. [ABSTRACT FROM AUTHOR]

Hydrophobic coatings that could survive in harsh environment have a wide range of applications from industry to houseware. However, the state‐of‐the‐art polymer‐based coatings cannot meet such requirements due to their low melting point and poor wear resistance. In this study, we reported a plasma sprayed ceramic coating made of ceria with exceptional hydrophobicity, high‐temperature stability, and good wear resistance. The coating exhibited a water contact angle (WCA) up to 139°, due to the intrinsic hydrophobicity of ceria and unique surface morphology produced by plasma spraying. The WCA only slightly decreased to 131° after annealing at 773 K. In addition, the polished coating (WCA ~ 116°) was still more hydrophobic than the sintered bulk specimen (WCA ~ 95°) with the same composition and roughness, which can be attributed to the surface chemistry change induced by Ar+ ion bombing by plasma. It is believed that such robust hydrophobic coating should have great potential in engineering application. [ABSTRACT FROM AUTHOR]

• The introduction of V replaced a part of the P in HAP by VO 4. • VHAP catalyst shows higher selectivity of cyclohexene than that of VO x /HAP catalyst prepared by the wet impregnation method. Vanadium oxide-modified hydroxyapatite (HAP) with varying vanadium content was synthesized by the coprecipitation and impregnation methods. The structures of the two series of catalysts were compared, and the effects of vanadium content on catalytic properties in cyclohexane oxidative dehydrogenation (ODH) are evaluated. The XRD, UV‒Vis and XPS analyses indicate that the V species in the two series of samples exist in different chemical environments. The samples prepared by the impregnation method are mainly composed of V 2 O 5 species, while the samples prepared by the coprecipitation method show a replacement of a part of the P in the HAP lattice by VO 4. The influence of the preparation method and vanadium content on the reaction rate and reaction route for the ODH of cyclohexane is investigated. VHAP shows higher cyclohexene selectivity. The effect of VO x species on the ODH reaction of cyclohexane was investigated and the reaction mechanism was proposed. [Display omitted] [ABSTRACT FROM AUTHOR]

Construction sites remain one of the most hazardous workplaces globally. To improve workplace safety in the construction industry and reduce the personal injuries and socioeconomic impacts resulting from workplace accidents, tacit knowledge containing fundamental causes of accidents or specific contextual factors can be extracted from past accident narrative reports. However, manually analyzing unstructured or semistructured textual data stored in records is a daunting task, and requires the use of automated and intelligent technologies to achieve rapid and accurate knowledge acquisition. Therefore, this paper proposes a text self-classification model based on deep learning natural language processing (NLP) technology for automated classification of construction site accident cases by accident type. First, combined with two statistical measures, mutual information and information entropy, the preprocessed text data were subjected to phrase segmentation to identify more complete and accurate accident precursor information without human intervention. Then a complete multilayer and multisize convolutional neural network (CNN) model was constructed using pretrained Word2Vec word embeddings for text self-classification tasks. Finally, the test results of the CNN classification algorithm were compared with the practical application results of three shallow learning algorithms, and the performance of different types of classification algorithms was evaluated. The results showed that the CNN-based deep learning algorithm developed in this paper demonstrated excellent feature extraction and learning abilities in the task of automatic text classification in the field of NLP. This not only demonstrated that reliable accident prevention knowledge could be obtained from the textual descriptions of construction accidents, but also provided a novel model reference for document archiving and information retrieval. [ABSTRACT FROM AUTHOR]

This paper investigates the valuation of vulnerable European options considering the market prices of common systematic jump risks under regime-switching jump-diffusion models. The way of regime-switching Esscher transform is adopted to identify an equivalent martingale measure for pricing vulnerable European options. Explicit analytical pricing formulae for vulnerable European options are derived by risk-neutral pricing theory. For comparison, the other two cases are also considered separately. The first case considers all jump risks as unsystematic risks while the second one assumes all jumps risks to be systematic risks. Numerical examples for the valuation of vulnerable European options are provided to illustrate our results and indicate the influence of the market prices of jump risks on the valuation of vulnerable European options. [ABSTRACT FROM AUTHOR]

• A new parameter calibration method is verified. • The calibration feasible solutions of fertilizer particle contact parameters are obtained. • RBFNN model and MIGA have good applicability in this study. • DEM virtual simulation tests and numerical analysis were conducted. • Technical support is provided for calibration of relevant granular materials. The discrete element method (DEM) can accurately predict and describe the motion behavior of granular materials; it has been widely used in related research in all walks of life. However, the material microscopic parameters involved in a simulation are difficult to measure using experimental methods, and the accuracy of the microscopic parameters has a direct impact on the predicted material motion behavior. In this study, a new calibration method was used to calibrate contact parameters commonly used in DEM simulations for fertilizer particles. The angle of repose (AoR) and the bulk height were selected as macroscopic response indicators, and the coefficient of restitution, coefficient of static friction, and coefficient of rolling friction of fertilizer particles were used as the parameters to be calibrated in the study. The input parameters required for the training of the radial basis function neural network (RBFNN) were obtained by combining Latin hypercube sampling with funnel stacking simulations. Finally, a multi-island genetic algorithm (MIGA) was used to optimally solve the approximate model, and comparative experiments and discharge experiments were conducted to validate the model. The results show that the sphericity of the fertilizer particles in the study is 90%, and spherical particles can be used instead in the simulation. Additionally, the approximate model obtained from the RBFNN training has a high model fit to the input and output parameters and a good prediction capability for the macroscopic behavior generated by the input parameters of the fertilizer particles. The result generated from the calibration was a set of data solutions, and the errors were less than 5% after validation of the data. Further experimental validation was done using the discharge experiment, which was consistent with the simulation results, indicating that the calibration results can accurately reflect the macroscopic motion behavior of the fertilizer particles, further illustrating the reliability of the method. [ABSTRACT FROM AUTHOR]

Buckwheat plant height is an important indicator for producers. Due to the decline in agricultural labor, the automatic and real-time acquisition of crop growth information will become a prominent issue for farms in the future. To address this problem, we focused on stereo vision and a regression convolutional neural network (CNN) in order to estimate buckwheat plant height. MobileNet V3 Small, NasNet Mobile, RegNet Y002, EfficientNet V2 B0, MobileNet V3 Large, NasNet Large, RegNet Y008, and EfficientNet V2 L were modified into regression CNNs. Through a five-fold cross-validation of the modeling data, the modified RegNet Y008 was selected as the optimal estimation model. Based on the depth and contour information of buckwheat depth image, the mean absolute error (MAE), root mean square error (RMSE), mean square error (MSE), and mean relative error (MRE) when estimating plant height were 0.56 cm, 0.73 cm, 0.54 cm, and 1.7%, respectively. The coefficient of determination (R2) value between the estimated and measured results was 0.9994. Combined with the LabVIEW software development platform, this method can estimate buckwheat accurately, quickly, and automatically. This work contributes to the automatic management of farms. [ABSTRACT FROM AUTHOR]

NiS 2 hollow spheres with controllable size have been synthesized by a facile hydrothermal method through the exchanging reaction between rod-like supramolecular precursor and l -cysteine. Through modifying the diameter of rod-like precursor as template, accompanied by concomitant Rayleigh instability and chemical nonequilibrium interdiffusion, the size of NiS 2 hollow sphere can be tuned ranging from nanosize to microsize. The hollow morphology of as-obtained product was attributed to the Kirkendall effect involving different transport rates for Ni and S ions. Owing to the relatively large specific area, the as-obtained nanoscale NiS 2 hollow sphere manifest remarkable photo co-catalytic performance for H 2 production, which generate 5.8 mmol of H 2 gas under the irradiation of visible light after 6 h and 0.97 mmol/h of average H 2 production rate, indicating superior H 2 production performance of NiS 2 hollow spheres. [ABSTRACT FROM AUTHOR]

Currently, the MgO expansion agent is widely used to reduce the cracking risk of concrete. The influence of MgO reactivity (50 s and 300 s) and dosage (0, 4 wt.% and 8 wt.%, by weight of binder) on the air void, pore structure, permeability and freezing–thawing (F–T) resistance of concrete were studied. The results indicate (1) the addition of 4–8 wt.% reactive MgO (with reactivity of 50 s and termed as M50 thereafter) and weak reactive MgO (with reactivity of 300 s and termed M300 thereafter) lowers the concrete's compressive strength by 4.4–17.2%, 3.9–16.4% and 1.9–14.6% at 3, 28 and 180 days, respectively. The increase in MgO dosage and reactivity tends to further reduce the concrete strength at all hydration ages. (2) Permeability of the concrete is closely related to the pore structure. M50 can densify the pore structure and lower the fraction of large capillary pores at an early age, thus it is beneficial for the impermeability of concrete. In contrast, M300 can enhance the 180-day impermeability of concrete since it can densify the pore structure only at a late age. (3) The influence of MgO on F–T resistance is minor since MgO could not change the air void parameters. (5) MgO concretes exhibit obvious fractal characteristics. The fractal dimension of the pore surface (Ds) exhibits a close relationship with the permeability property of concrete. However, no correlation can be found between F–T resistance and Ds. [ABSTRACT FROM AUTHOR]

The large porosity, high water absorption and many inherent micro-cracks in recycled aggregates are the key causes of the weaker mechanical properties, higher drying shrinkage and even vulnerability to early-age cracking in recycled aggregate concrete (RAC). A method of using the polymer aluminium sulfate (PAS) to enhance the mechanical properties and volume stability of RAC is presented. Three basic mechanical properties (compressive strength, flexural strength and elastic modulus) and two volume stability parameters (free drying shrinkage and restrained shrinkage cracking) were evaluated along with a few parallel tests of PAS at the microstructural level. The microstructure of the interfacial transition zone (ITZ) in RAC was characterised by micro-hardness tests and scanning electron microscopy. The test results show that the PAS, due to its chemical function, is capable of effectively increasing the micro-hardness and reducing the inhomogeneity of the ITZ in RAC. These improvements in the microstructure of RAC with PAS contribute to improving the mechanical properties, reducing the drying shrinkage and retarding the restrained shrinkage cracking period of RAC. [ABSTRACT FROM AUTHOR]

Hydrophobic coatings based on organic or ceramic materials usually suffer from low wear resistance and poor thermal stability, which limit their practical applications. Here we report a robust, hydrophobic CeO 2 /NiCoCrAlY composite coating prepared by air plasma spraying (APS), which shows superior wear resistance, excellent high-temperature stability and high bonding strength with the substrate. The coating can maintain its hydrophobicity after abrasion under 10 kPa over a 4 m distance, or after annealing at 773 K for 8 h. It also presents good corrosion resistance to protect the metallic substrate under corrosive working conditions. The CeO 2 /NiCoCrAlY composite coating provides a reliable and effective route to fabricate hydrophobic surfaces which may have potential applications in harsh environments. • CeO 2 /NiCoCrAlY composite coatings were prepared by APS. • The coating with 80% CeO 2 can maintain its hydrophobicity after abrasion under 10 kPa over a 4 m distance. • The coating with 80% CeO 2 can also maintain its hydrophobicity after annealing at 773 K for 8 h. • The coating can protect the substrate from corrosion. • The robust, hydrophobic and thermally-stable coating is promising to work under harsh environments. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus (V. parahaemolyticus) is the causative agent for acute hepatopancreatic necrosis disease (AHPND) of shrimp, and it is also a common seafood-borne pathogen for humans. Rapid and accurate identification of V. parahaemolyticus is helpful to diagnose the AHPND and ensure food safety. Common detection methods suffer the deficiency of time-consuming and complexed operation. Based on the increased development of aptamer and our previous study, a new detection assay of V. parahaemolyticus was introduced, in which the aptamer combined with magnetic nanoparticles (MNPs) was the recognizer, hybridization chain reaction (HCR) was the signal amplifier, and lateral flow nucleotide biosensor (LFNB) was the signal exporter. The assay possessed high specificity of distinguishing the target with other bacteria, and the calculated limit of detection was 2.6 × 103 cells. Furthermore, the whole process just needs 67 min, free of thermocycle instruments and signal readout instruments, which means it is suitable for low-resource laboratories or districts. [ABSTRACT FROM AUTHOR]

To optimise the under-membrane fertiliser application of "one film for two years" technology, this paper established the model of T1 and T2 roller hole applicators and adopted discrete element method - multi-body dynamics (DEM-MBD) coupling technology to simulate the under-membrane fertiliser application process and to optimise water and fertiliser application using transport laws under the whole-membrane double-rowed furrow. The coupling results showed that when the roller hole applicator advances at 1 m s−1, the hole application volume of T1 and T2 models is 14.43 g and 15.02 g, respectively, the particle velocity of the membrane pore is 0.2–0.8 m s−1 and 0.2–0.96 m s−1, respectively, the resistance of the hole tying is 21.67 N and 21.41 N, respectively, and the soil disturbance velocity is respectively 1.54 m s−1 and 1.31 m s−1. The HYDRUS-2D/3D was used to simulate the under-membrane fertiliser application process. The results of HYDRUS-2D/3D showed that the water content of the soil in the furrow was 12.7–13.5%, the water absorption rate of the crop root system was 0.2 cm d−1, and the concentration value at the centre point of the fertiliser application in the furrow was 0.72–0.88 mg cm−3. The results of the study showed that the roller hole applicator meets the requirements of the "one-membrane-two-use" under-membrane fertiliser application of full-film dual-monopoly furrow. The results provide a theoretical basis for the optimisation and enhancement of water and fertiliser transport in full film two monopoly furrow. [Display omitted] • Simulation of fertilizer application using coupled DEM-MBD technique. • Particle modelling of full-film duopoly films using the discrete element approach. • HYDRUS-2D/3D simulation of soil water and fertilizer transport. • Integration of agro-mechanical and agronomic technologies. • Modelling two types of roller hole fertiliser applicators. [ABSTRACT FROM AUTHOR]

Livestock dung, discarded crop straws, and residual plastic film are the primary agricultural non-point sources of pollution. For livestock dung and discarded crop straw, the general treatment focuses on compost, animal fodder, industrial raw material, and new energy. The development of degradable mulch film is the main way to solve pollution from residual plastic film. However, an effective way to solve the above three types of pollution simultaneously and use them for ecological circular agriculture has been less studied. In this study, using cow dung and flax straw wastes as raw materials, we prepared natural, fibre-based paper mulch using the rapid-Kothen method and analysed the film-forming mechanism. Based on the Van Soest method, the cow dung and flax straw waste contain abundant cellulose fibres: 36.75% and 54.69%, respectively. The tensile strength and tear strength of fibre paper mulch are 1.87 kN/m and 19.91 N/mm, respectively. To enhance the adaptability of the fibre paper mulch in humid environments, the surface of the mulch was treated with alkyl ketene dimer (AKD). The AKD-coated fibre paper mulch displays hydrophobic properties, indicated by a contact angle of 128° ± 2°. It has a wet tensile strength of 0.64 kN/m and a wet tear strength of 8.23 N/mm. Additionally, it exhibits a dry tensile strength and a tear strength of 2.13 kN/m and 16.43 N/mm, respectively. Notably, the dry tensile strength is increased by 16.31%. In this way, the livestock dung and discarded crop straw can be reused, reducing dung pollution and straw burning in livestock farms, and the final products can alleviate the residual film pollution simultaneously. [ABSTRACT FROM AUTHOR]

Enhancing the photocatalytic stability of Cu2O in the degradation of tetracycline is a great challenge in combating environmental water pollution because it is prone to deactivation by photocorrosion in aqueous environment. In this study, Cu2O/cellulose microfiber aerogel is synthesized through freeze‐drying, utilizing the self‐curling effect of cellulose and then calcined to produce Cu2O/C composite aerogel. The derived Cu2O/C composite aerogel features hollow carbon microfibers anchored with Cu2O nanocubes. Due to the curling structure and conductivity of the carbon microfibers, the photodegradation efficiency of the obtained Cu2O/C composite aerogel for tetracycline is drastically improved to 97.3% under 120 min of visible‐light irradiation, and remains a cycling photodegradation rate of 84.3% after 10 cycles. The Cu2O/C composite aerogel shows remarkable strategies for designing and constructing Cu2O‐based photocatalyst in the practical photodegradation of tetracycline under visible‐light exposure. [ABSTRACT FROM AUTHOR]

• Effective foam ratio is put forward to express stability of foam in paste slurry. • Pore size and distribution greatly affect physical and mechanical properties. • Foam stability is the main factor affecting pore structure of AAS foamed concrete. • AOS can be preferred to prepare AAS foamed concrete. Alkali-activated slag cement has the characteristics of high viscosity, quick hydration, setting and hardening, and high strength, which are suitable for the preparation of foamed concrete. Three foaming agents of sodium α-olefin sulfonate (AOS), sodium dodecyl sulfate (K12) and sodium alcohol ether sulphate (AES) with the same foam stabilizer of silicone resin polyether emulsion FM-500 (MPS) were used to prepare foam. The three foam properties are similar and foam stability of AOS and K12 is better than that of AES. Effective foam ratio is put forward to express stability of foam in paste slurry. Effective foam ratio and porosity has a great effect on dry apparent density of water glass-activated slag foamed concrete. With the increase of foam content, effective foam ratio of AES decreases obviously, while that of K12 and AOS show a slight decrease. At low foam content, AES can better reduce the dry apparent density. Increase foam content of AOS and K12 appropriately may reduce dry apparent density. R sd and compressive strength of foamed concrete with AOS foam is the highest. When porosity is similar, average pore size and pore size distribution has a great effect on thermal conductivity and mechanical properties of AAS foamed concrete. Average pore size of O3 is smaller than that of K3 and E3. O3 also shows the narrowest air-void size distribution with the majority of the voids smaller than 400 μm. Average roundness of three type foam is much the same. Foam stability is the main factor affecting pore structure of AAS foamed concrete. AOS can be preferred to prepare AAS foamed concrete. [ABSTRACT FROM AUTHOR]

An auto-deformable supercapacitor which is composed of PPy(DBS) film (PPy doped with dodecyl benzene sulfonate anions, DBS−), reduced graphene oxide (rGO) film and Polyvinyl alcohol (PVA) gel electrolyte is fabricated. Benefiting from the synergy of flexible film electrodes and gel electrolyte, the volumetric effect of PPy(DBS) film produced by capacitance reaction is collected continually. The accumulated volumetric effect enables the as-designed supercapacitor to deform autonomously during the cyclic energy storage processes and generates more electrochemical active sites in PPy(DBS) film, which provides higher energy storage capacity for the supercapacitor. • Volumetric effect of PPy is collected and accumulated by synergy of flexible electrode and solid-state electrolyte. • The cumulative volumetric effect is applied to auto-deformable supercapacitor. • There is a quantitative relationship between the deformation degree and the capacitance. Polypyrrole (PPy) is one of the most extensively studied conducting polymers and it has promising application prospects in supercapacitors. However, PPy-based supercapacitors generally suffer from poor cycling stability due to the volumetric effect induced by ion doping/de-doping during the redox reactions. Therefore, the volumetric effect has usually been considered deleterious for supercapacitor applications. Herein, we demonstrate that the volumetric effect of PPy can be collected by synergy of flexible electrodes and solid-sate electrolytes. Furthermore, the accumulative volumetric effect is utilized in auto-deformable supercapacitors for the first time. The as-designed supercapacitor consists of flexible electrodes (PPy film, reduced graphene oxide (rGO) film) and a polyvinyl alcohol (PVA) gel electrolyte. When the redox reaction starts, the volumetric change of the PPy film induced by Na+ ion insertion is captured by the PVA gel electrolyte, resulting in mechanical deformation of the supercapacitor. As the accumulative volumetric effect drives greater deformation of the device, more electrochemically active sites are generated in the PPy film, leading to a higher energy storage capacity of the supercapacitor. Specifically, a certain correlation exists between the deformation degree and the energy storage capacity. As the deformation degree approaches 100% from 0%, the discharge capacity increases to 359 mF/cm3 from 101 mF/cm3. This auto-deformation characteristic endows the supercapacitor with subjective initiative, which establishes an important foundation for a smart energy storage device. [ABSTRACT FROM AUTHOR]

Water glass (WG) is generally considered to be the most effective activator to prepare alkali-activated slag (AAS) cement in terms of strength and durability. However, the rapid setting and hardening of WG activated slag results in rapid loss of fluidity of AAS concrete mixture, which limits its engineering application. In the paper, the effect of blended inorganic salts containing negative hydration ions on the fluidity, setting time and mechanical strength of AAS cement was studied. The hydration process and hydration products were used to explore the action mechanism. Ba(NO 3) 2 greatly delayed the hydration of AAS cement. The four inorganic salts (KCl, KNO 3 , KBr and NaCl) blended with a small amount of Ba(NO 3) 2 can improve both the initial fluidity and fluidity retention, and a wide setting time range can be obtained to meet engineering requirements. The compressive strength decreased with the increase of inorganic salts. The incorporation of inorganic salt did not change the composition of the main hydration products. Considering the fluidity required by construction, mechanical properties and the durability of structure, it is recommended to add 4%–5% KBr or KNO 3 blended with no more than 0.2% Ba(NO 3) 2 into AAS cement. [ABSTRACT FROM AUTHOR]

This paper tackles the problem of noise suppression during vital sign signal monitoring. Physiological signal monitoring is a significant and promising medical monitoring method, and wearable medical monitoring devices based on piezoelectric polymer sensors are a trending way for their advantages of being flexible in the shape, portable to use, and comfortable to wear. However, this raises the question that the measured signal contains much more noise components. To avoid the following shortcoming of low signal to noise ratio (SNR), a noise suppression method based on improved wavelet threshold and empirical mode decomposition combined with singular value decomposition (SVD) screening the intrinsic mode function (IMF) components is proposed. A wavelet transform is first used under the combination of hard and soft thresholds to focus the target range in the low-frequency region where the energy of the physiological signal is concentrated. Then, a complete ensemble empirical mode decomposition is used to decompose the signal effectively, which can resist the influence of random noises. Meanwhile, a SVD decomposition procedure was used to filter out the lower correlated IMF components to retain the validity of the original signal. We verified the effectiveness of the proposed method through simulated and measured experiments as well as the advantages and disadvantages of the algorithm compared with other physiological signal denoising algorithms through SNR filtering results, power spectrum distribution, and other perspectives. The results proved that the proposed method could effectively remove more detailed noise and improve the SNR of the signal efficiently, which is more conducive to the demand for auxiliary medical diagnosis in the future. [ABSTRACT FROM AUTHOR]

Industrial metabolism and symbiotic coupling has become the base paradigm of green, low-carbon development of coal mining. In the coal industrial symbiosis system (CISS), stability is increasingly fragile because of its unique industrial links and growth environment. Referring to the classic Lotka-Volterra population ecology model, and synthesizing the periodicity and time lag effects of industrial development, two entirely novel and more generalized CISS evolution models with time lag effects in the competitive and reciprocal scenarios are constructed respectively. Moreover, the conditions of CISS stability are proven and discussed through mathematical analysis. Simulation and theorem validation were carried out by taking the largest Chinese coal city, Ordos, as the research object. The main results are as follows. First, the time lag effect is an important factor leading to CISS instability. The shorter the time lag within the CISS, the better the collaboration between industries, and the easier it is that the CISS will achieve a stable ecological balance. Second, when the power of competition dominates, the development of industries within CISS will be inhibited; when the power of cooperation dominates, the evolution of CISS will toward a positive direction. Third, a certain degree of self-inhibition will contribute to the stable development of the industrial symbiosis system. At last, the social service industry not only can boost the industrial diversity within CISS, but also can promote the co-evolution of original and exogenous industries, which plays a positive role in the healthy and stable development of CISS. [ABSTRACT FROM AUTHOR]

Wire-shaped supercapacitors (WSSCs) are of considerable interest for next-generation wearable electronics. However, the poor stretchability of WSSCs based on inelastic yarn electrode seriously lead to the deficient size-adjustability of the devices. Herein, a novel kind of highly conductive, flexible and elastic yarn electrode has been put forward, which is realized by coating electro-active carbon nanotubes (CNTs) network onto the Ag-plated double-covered yarns (Ag-DCYs). On the one hand, highly conductive Ag-DCYs with “twining spring” architecture serve as the elastic substrate of the electrode. On the other hand, thin CNTs layer is uniformly wrapped on the whole yarns, which provides remarkable electrochemical capacitance for the electrode. Benefiting from the intriguing configuration, WSSCs based on the yarn electrode act as the efficient energy storage devices, which exhibit high volumetric energy density (4.17 mWh/cm 3 ), volumetric power density (1080 mW/cm 3 ), strong durability. More importantly, the integrated devices are randomly bendable and stretchable without the degradation of electrochemical performance. Such superior energy storage performance and steady electrochemical behaviors under high strain (150% maximum) have almost never been reported before. As a result, the WSSCs can be readily knitted with textiles and woven into different shapes, which distinctly represent the available self-stretchable and size-adjustable ability, thereby throwing light on a new avenue for the development of wearable electronics. [ABSTRACT FROM AUTHOR]

The agronomic technology of whole plastic-film mulching on double ridges has been widely promoted in the arid region of northwest China, which has caused serious residual film pollution in the field. Mechanized residual plastic-film collecting is the main way, but this way of residual plastic-film collecting is more complicated. To prove the effect of typical film-lifting parts on residual plastic-film collecting performance by a numerical simulation method, further evaluate and select the working parts suitable for residual plastic-film collecting and improve the collecting efficiency, virtual whole plastic-film mulching on double ridges needs to be established. In this study, the film-lifting parts and the double ridge with flexible, deformable, mulching, film interaction model was developed using the discrete element method (DEM). The interaction model was used to simulate the operation process of a typical third-order shovel, hug plate and elastic teeth film-lifting parts. Furthermore, the operation resistance, seed bed disturbance and collecting residual film form under different working conditions were analyzed. The simulation results show that: the disturbance of the ridge from strong to weak is the third-order shovel, elastic teeth and hug plate film-lifting parts; the crushing of the ridge soil from strong to weak is the elastic teeth, the hug plate and the third-order shovel film-lifting parts; the collecting film from strong to weak is the hug plate, elastic teeth and the third-order shovel film-lifting parts; the median value of the horizontal force fluctuation range of the ridge soil on the film-lifting parts is increased, and the increase trend is from large to small in the third-order shovel, elastic teeth and hug plate film-lifting parts (the third-order shovel is 5250 N, 6250 N and 7750 N; the hug plate is 3250 N, 3500 N and 4000 N; and the elastic teeth are 4150 N, 4550 N and 5450 N). The comparative analysis results show that the hug plate film-lifting parts are more suitable for the residual-film collecting of whole plastic-film mulching on double ridges. Field trials were carried out to verify the operational effectiveness of the hug plate film-lifting parts. The results show that the morphological changes of the recovered residual film and the simulated mulching film during the operation of the hug plate-type residual film machine, and the distribution of the surface properties of the ridge after the residual-film collecting are basically consistent with the simulation results, and the film pick-up rate of hug plate film-lifting parts reaches 95.20%, and the established discrete element interaction model is reliable. The research results can provide reference for the research and development of full film duopoly furrow-mechanized residual film-collecting agricultural equipment in the arid region of northwest China. [ABSTRACT FROM AUTHOR]

In the context of the depth adjustment of the global economy and wild fluctuations in energy prices, the vulnerability issue of the coal mining industrial ecosystem (CMIES) has seriously affected the sustainable development of the regional economy. Comparisons of CMIES health status at a regional level are worthy of being conducted. This not only contributes to understanding a particular coal mining area's situation in regards to CMIES vulnerability, but also helps to discover a meaningful benchmark to learn the experiences in terms of action programmes formulation. In this study, based on the analysis of the vulnerability response mechanism of CMIES to economic fluctuations, an initial indicator system for vulnerability assessment of CMIES was constructed. Ultimately, 14 vulnerability-evaluating indicators and their weights were obtained using rough set attribute reduction. Based on a composite CMIES Vulnerability Index (CVI), the Rough Set-Technique for Order Preference by Similarity to Ideal Solution-Rank-sum Ratio (RS-TOPSIS-RSR) methodology is proposed to conduct the CMIES vulnerability assessment process from an overall perspective. Using this methodology, 33 coal mining areas in China are ranked as well as grouped into three specific groups based on the CVI score. The results demonstrate the feasibility of the proposed method as a valuable tool for decision making and performance evaluation with multiple alternatives and criteria. [ABSTRACT FROM AUTHOR]

Graphene resonant sensors have shown strong competitiveness with respect to sensitivity and size. To advance the applications of graphene resonant sensors, the damage behaviors of graphene harmonic oscillators after thermal annealing and laser irradiation were investigated by morphology analysis and frequency domain vibration characteristics. The interface stress was proven to be the key factor that directly affected the yield of resonators. The resulting phenomenon could be improved by appropriately controlling the annealing temperature and size of resonators, thereby achieving membrane intactness of up to 96.4%. However, micro-cracks were found on the graphene sheets when continuous wave (CW) laser power was more than 4 mW. Moreover, the fluctuating light energy would also cause mechanical fatigue in addition to the photothermal effect, and the threshold damage power for the sinusoidally modulated laser was merely 2 mW. In this way, based on the amplitude-frequency surface morphology of the graphene resonator, the thermal time constant of the order of a few microseconds was confirmed to evaluate the damage of the graphene oscillator in situ and in real time, which could be further extended for those resonators using other 2D materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • This is the first time to report precocious puberty and growth retardation male Macrobrachium rosenbergii by transcriptome sequencing. • The data presented here reveals key insights into the genetic markers of precocious puberty and growth retardation of male M. rosenbergii. Macrobrachium rosenbergii is an important economic aquatic animal and has been cultivated worldwide. However, it has suffered a disease of precocious puberty and growth retardation. This disease was also called iron prawn syndrome (IPS) in recent years. However, the cause of this disease has thus far remained a mystery. The present work utilized transcriptome sequencing technology to acquire gene expression information of gonads and to find the differentially expressed genes(DEGs) between diseased and normal male prawn. Finally, 426 significantly expressed genes were identified(p less than 0.01, |log2FC|≥1), of which 171 genes were up-regulated and 255 were down-regulated. Furthermore, DEGs were annotated to 36 GO terms and 202 KEGG pathways. Enrichment analysis of DEGs resulted in 10 significantly enriched GO terms and a total of 12 significantly enriched KEGG pathways. Analysis of the transcriptome sequences and DEGs identified several unigenes and pathways involved in precocious puberty and growth retardation. Quantitative PCR was performed to validate accuracy of the RNA-seq and the expression level of 10 genes, calculated by two analysis method, was mostly consistent. This is the first time to report precocious puberty and growth retardation male M. rosenbergii by transcriptome sequencing. The data presented here reveals key insights into the genetic markers of precocious puberty and growth retardation of male M. rosenbergii. [ABSTRACT FROM AUTHOR]

Ultrathin Ti-doped α -Fe 2 O 3 photoanode was prepared by a facile atmospheric pressure chemical vapor deposition method through pyrolysis of ferrocene at 450 °C on Ti foil. The as prepared ultrathin hematite thin film has a surface feature size of 70 × 30 nm and a thickness of 50 nm. The photocurrent of this ultrathin hematite photoanode prepared at 450 °C in 1 M NaOH reaches 900 μA/cm 2 at 0.6 V SCE under AM 1.5G illumination. The superior performance to the thin films prepared on FTO glass was ascribed to the diffusion and doping of Ti 4+ from the metal substrate during pyrolysis deposition of hematite on Ti substrate. [ABSTRACT FROM AUTHOR]

As the important electric loss of a graphene resonator, intrinsic current loss has received increasing attention, but the existing research is limited to qualitative analysis and approximate calculation. Based on the microscopic behavior of carriers, we have accurately established the calculation model of induced current loss, which is in good agreement with the existing experimental results. Compared with the previous models, the model in this work can not only fit the inverse V-shaped Q − Vdc curve well but also be compatible with the V-shaped Q − Vdc curve, which is beyond the reach of the previous models. In addition, the calculation results show that selecting the appropriate gate voltage combination when stimulating the graphene resonator can increase the quality factor by nearly 1–2 orders of magnitude. Furthermore, we reasonably explain the importance of DC gate voltage applied in the experiment compared with the case of non-DC gate voltage. This work realizes the accurate calculation of intrinsic current loss and is of great significance for reducing the intrinsic current loss in the practical application of graphene resonators. [ABSTRACT FROM AUTHOR]

Near-neutral salt activated slag cement has better performance in environmental protection and shrinkage behavior than common sodium silicate -activated slag (AAS) cement. However, the growth of mechanical performance is too slow, which limits its application. Reactive MgO can improve early mechanical properties, while it may have different effects on the shrinkage due to changes in alkali-activators. Two near-neutral salts, sodium carbonate (SC) and sodium sulfate (SS), were selected to prepare AAS cement. The influence of reactive MgO on autogenous and drying shrinkages was studied. The hydration process and pore structure were assessed with hydration heat and nitrogen adsorption, respectively. The phase composition was evaluated by thermogravimetry (TG/DTG) and X-ray diffraction (XRD). The results indicate that the addition of reactive MgO increases the autogenous shrinkage of SC and SS activated slag. This is mainly due to accelerated reaction by reactive MgO. The drying shrinkage of AAS mortars activated with SC increases first and then decreases with the increase in reactive MgO. For SS activated slag, the more the reactive MgO used, the lower the drying shrinkage is observed. This is related to the effect of reactive MgO on pore structure and hydration products. When reactive MgO increases from 2% to 10%, the mesopore in SC activated slag increases at first and then decreases, while the SS activated slag group shows a constant decrease. Reactive MgO promotes the formation of hydrotalcite in SC activated slag, while AFt is found in SS activated slag. Hydrotalcite and AFt are crystalline products, which are beneficial to inhibit drying shrinkage. [ABSTRACT FROM AUTHOR]

CO 2 methanation is a promising strategy to convert the greenhouse gas into synthetic natural gas, which is known as a clean fuel with higher energy density. Ni/CeO 2 is one of the active catalysts for CO 2 methanation reaction. However, Ni/CeO 2 with conventional metal/support structure suffers from the problem of nanocrystal coarsening during high-temperature reaction and thus decreasing catalytic activity. In this work, a Ni/CeO 2 catalyst with novel structure was designed and synthesized through impregnation of Ce-based metal organic framework (MOF) with Ni precursor followed by calcination process. Due to the confinement effect of ultra-small pores derived from the MOF, Ni/CeO 2 catalysts with ultrafine Ni nanoparticles, high dispersion and good thermostability were resulted. Among all the samples, Ni/CeO 2 calcined at 600 °C showed the best catalytic performance due to the highest amount of oxygen vacancies. This work demonstrates a facile way to synthesize a broad range of ultra-fine metal/metal oxide nanocomposite catalysts with high catalytic activity and good stability for various applications. [ABSTRACT FROM AUTHOR]

In this study, the typical wet impregnation method was employed to prepare advanced electrocatalysts for oxygen evolution reaction (OER). The preparation process is easy‐operation and doesn't require any complex synthesis steps. This strategy was demonstrated with Fe3+/Ni2+ loaded on porous carbon as an example. The thus formed pre‐catalyst was in situ activated in the electrochemical test process, during which the electrochemically active species for OER are achieved. With the optimized catalyst, a current density of 10 mA.cm−2 can be obtained at an overpotential of 275 mV. This catalytic performance is close to or even better than the benchmarked RuO2 and IrO2 catalysts. Especially, the catalyst also exhibits good catalytic stability. This study presents a new non‐chemical synthesis route for advanced oxygen evolution catalysts. [ABSTRACT FROM AUTHOR]

• Fabrication of high consistent spin-coated optical fiber photoacoustic generator. • High consistent and high-frequency broadband miniature photoacoustic generator. • Potential in high-resolution ultrasound imaging with high signal to noise ratio. Optical fiber photoacoustic (PA) probe is considered to have great prospects in high resolution invasive imaging due to the advantages of flexible, miniaturized broadband ultrasonic excitation. Unfortunately, more attentions are currently focused on the fabrication of the PA probe with a high PA conversion efficiency, instead of the consistency of the developed probe that is of great importance for practical applications. In this paper, in consideration of the coating thickness and flatness closely concerned with the consistency, a number of PA probes with 15 wt.% carbon nanoparticles (CNPs) and polydimethylsiloxane (PDMS) composite were fabricated by a spin-transfer method with the help of transferring uniformly spin-coated film on the endface of an optical fiber. Underwater ultrasonic detection showed that the fabricated probes exhibited a good consistency with the corresponding lower coefficients of variation of 1.7%, 1.4% and 1.1% for the sound pressure, center frequency and bandwidth, sharply reduced by 89%, 72% and 81% in comparison with the commonly used dip-coating probes tested in this work. Also, due to the thinner film obtained through the presented fabrication method, the maximum PA pressure value of 1.04 MPa with a -6 dB bandwidth of 54.2 MHz was achieved, which further demonstrates a great potential in high-resolution ultrasound imaging utilizing multiple probes with high consistency. [ABSTRACT FROM AUTHOR]

Exploring a low-cost and high-performance oxygen evolution catalyst for water splitting to produce clean energy hydrogen is a hot topic. In this study, a simple physical adsorption strategy was used to prepare pre-catalysts of Fe3+–Co2+ species on carbon for the oxygen evolution reaction (OER). The optimized precatalyst shows an excellent electrocatalytic performance, delivering a current density of 10 mA cm−2 at a low overpotential of 295 mV with a small Tafel slope of 61.3 mV dec−1 in 1 M KOH. This study proposes the design of efficient oxygen evolution catalysts by a typical physical adsorption route. [ABSTRACT FROM AUTHOR]

Self-standing film with desirable properties is a promising candidate for flexible electronic applications. Conducting polymers (CP) have intrinsic film forming and pseudocapacitive characteristics. However, pure CP films are rarely applied in energy storage devices due to their disordered molecular structure which would result in insufficient utilization of the supported active materials and apparent volumetric effect. The specific lamellar structure of 2D nanosheets is an ideal platform for CP growing into self-standing film with desirable structure. Herein, a facile interface engineering strategy is proposed for in-situ integrating 2D MoS 2 nanosheets into 3D polypyrrole (PPy) framework, in which dodecylbenzene sulfonate (DBS−) anions intercalate into MoS 2 nanosheets and guide PPy to grow into ordered molecular structure. The resultant self-standing films with PPy chains in a high degree of ordering can deliver a high area capacitance of 1200 mF/cm2 and a high volumetric capacitance of 325 F/cm3, which are significantly superior to pure PPy films and show a great potential for high performance flexible supercapacitor application. Image 1 [ABSTRACT FROM AUTHOR]

Designing defect‐rich MoS2/C architectures with three‐dimensional (3D) porous frame effectively improve the electrochemical performance of lithium‐ion batteries (LIBs) owing to the improved conductivity and decreased diffusion distance of Li+ ions for lithium storage. Herein, we report a reliable morphology engineering method combining with tunable defects to synthesize defect‐rich MoS2 nanosheets with a few layers entrapped carbon sheath, forming a 3D porous conductive network architecture. The defect‐rich MoS2 nanosheets with expanded interlayers can provide a shortened ion diffusion path, and realize the 3D Li+ diffusion with faster kinetics. A 3D conductive interconnected carbon network is able to improve interparticle conductivity, concurrently maintaining the structural integrity. Benefiting from these intriguing features, the as‐prepared MoS2/C architectures exhibit excellent electrochemical performance: a high reversible capacity of 1163 mAh g−1 at a current density of 0.1 A g−1 after 100 cycles and a high rate capability of 800 mAh g−1 at 5 A g−1. Defect content in MoS2/C architectures can be obtained by changing H2 concentration. Compared with the counterparts with few defects, the defect‐rich MoS2/C architectures show improved electrochemical stability with a superior cycle life, illustrating a highly reversible capacity of 751 mAh g−1 at 0.5 A g−1 after 500 cycles. [ABSTRACT FROM AUTHOR]

• A novel pseudocapacitive quantum dots (QDs) based electrode. • Pseudocapacitive QDs confined in two-dimensional nanospace. • Improved active sites and surface wettability of the electrode. • Favorable electrochemical kinetics of the electrode. • Superior electrochemical behaviors in IL-based supercapacitors. Assembling supercapacitors (SCs) using high-voltage ionic liquid (IL) as electrolyte is an effective strategy to enhance the energy density of SCs. Herein, a novel pseudocapacitive quantum dots (QDs)-based electrode with superior electrochemical behaviors in IL electrolyte has been put forward. Remarkably, FeOOH QDs (FQDs) are effectively confined in a two-dimensional (2D) nanospace supported by porous N-doped carbon (PNC) derived from graphitic carbon nitride (g-C 3 N 4). Beneficial from the abundant active sites and high surface wettability, the resultant FQDs/PNC electrode exhibits sufficient redox reaction and favorable electrochemical kinetics in IL electrolyte. As a result, it can deliver a large specific capacitance of 210.6 F g−1 and still retain 82.2% of its initial capacitance after 10,000 cycles. [ABSTRACT FROM AUTHOR]

Microcystins (MCs) is a harmful toxin generated by blue‐green algae in water, which has seriously threatened the ecological safety of water and human body. It is urgent to develop new catalysts and techniques for the degradation of MCs. A feasible electrostatic self‐assembly method was carried out to synthesize BiVO4/g‐C3N4 heterojunction photocatalyst with highly efficient photocatalytic ability, where BiVO4 nanoplates with exposed {010} facets anchored to the g‐C3N4 ultrathin nanosheets. The morphology and microstructure of the heterojunction photocatalysts were identified by XRD, SEM, TEM, XPS, and BET. The g‐C3N4 nanosheets have huge surface area over 200 m2/g and abundant mesoporous ranging from 2‐20 nm, which provides tremendous contact area for BiVO4 nanoplates. Meanwhile, the introduction of BiVO4 led to red‐shift of the absorption spectrum of photocatalyst, which was characterized by UV‐vis diffuse reflection spectroscopy (DRS). Compared with pure BiVO4 and g‐C3N4, the BiVO4/g‐C3N4 heterojunction shows a drastically enhanced photocatalytic activity in degradation of microcystin‐LR (MC‐LR) in water. The MC‐LR could be removed within 15 minutes under the optimal ratio of BiVO4/g‐C3N4. The outstanding performance of the photocatalyst is attributed to synergetic effect of interface Z‐scheme heterojunction and high active facets {010} of BiVO4 nanoplates, which provides an efficient transfer pathway to separate photoinduced carriers meanwhile endows the photocatalysts with strong redox ability. [ABSTRACT FROM AUTHOR]

• Improved text segmentation techniques can automatically and accurately generate more complete phrases. • Data pre-processing techniques that have undergone oversampling and correlation coefficient measurements enable more complete processing of sample data. • The outcomes of the accident severity prediction in distinct scenarios demonstrate the reliable performance of the feature attribute-based prediction model. • The ranking results of feature importance can adequately identify and explain the critical attribute factors of occupational accidents. Machine learning algorithms are capable of handling complex non-linear problems related to the prediction domain, but further exploration is required for automated, semi-supervised outcome prediction of occupational accidents employing unstructured textual data. It has been demonstrated that the injury severity can be predicted from the equipment, scenario and environmental attributes in the workplace, so this paper aims to enhance text data pre-processing and optimize machine learning algorithms to create an attribute factor-based occupational accident severity prediction framework, mapping characteristic attributes to accident severity categories (i.e., casualties and property damage). The reliability validation of the prediction framework and analysis of critical attribute components are performed using the collapse accidents data in construction engineering as a case study, which is the third most serious occupational problem. The findings indicate that the dataset obtained after addressing the class imbalance issue and improving the text segmentation procedure can be utilized as a training sample to accurately predict injury severity. The accuracy of the prediction model is evaluated in three simulated scenarios, and it can reach 82%, confirming the robust performance of the prediction model based on RF machine learning. Additionally, the outcomes of the measured ranking of feature importance enable the identification of critical attributes that can credibly explain the causal relationships resulting in injury severity findings, and provide managers with accident prevention strategies to minimize occupational injuries and losses. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Design and synthesis of C/α-Fe 2 O 3 /Si NW photocathode. • A thin carbon passivation layer deposited through ion sputtering. • The composite photoelectrode shows a stable photocurrent in the neutral solution. Abstract Tremendous efforts have been dedicated to the development of transition metal and/or metal oxide surface coating materials to enhance the activity and stability of photoelectrodes. Nanostructured Si photoelectrodes have shown outstanding photoelectrochemical (PEC) performance due to their effective photon absorption and charge generation, separation, and mobility. While the chemical stability and surface reaction efficiency of Si photoelectrodes still need improvement before commercial application. Herein, we report the design and synthesis of a composite Si photoelectrode with a configuration of C/α-Fe 2 O 3 /Si nanowires, which presented a stable photoelectrochemical hydrogen production in neutral electrolyte. The p-Si nanowires were prepared by metal-assisted chemical etching for enhanced optical absorption and decorated with a mesoporous α-Fe 2 O 3 thin film (∼80 nm) through pyrolysis of ferrocene. A thin carbon passivation layer (∼20 nm) was further deposited through ion sputtering further increasing the stability of the composite structure and low bias photocurrent. The role of α-Fe 2 O 3 and carbon layer have been discussed. The composite photoelectrode shows a stable photocurrent of ∼−27 mA/cm2 in 2 h and an anodic onset potential shift of ∼0.33 V relative to the bare Si in the neutral solution. [ABSTRACT FROM AUTHOR]

Abstract Cu 2 O nanowires have been grown on Cu substrates by electrochemical etching followed with dehydration annealing. The as resulted films show excellent hydrophobic performance without organic surface modification. The contact angles (and slide angles) of the as-resulted Cu 2 O nanowire films grown on Cu mesh, Cu foam, and Cu foil are 168.3 ± 0.09° (slide angle 19°), 171.7 ± 0.28° (slide angle 22°), and 172.8 ± 0.96° (slide angle 2°), respectively. The Cu 2 O nanowire films on Cu foil represent the best hydrophobic activity for copper-based surfaces without any organic modification and additives. The special configurations of the Cu 2 O nanowire films on the Cu substrates and their surface energies both have impacts on the excellent hydrophobic performance. The growth mechanism and the performance-structure relationship of the Cu 2 O nanowire films are also discussed. This study suggests a low-cost and environment friendly method for the preparation of hydrophobic coating material. Graphical abstract Image 1 Highlights • Cu 2 O nanowires have been grown on Cu substrates by electrochemical etching followed with annealing. • The Cu 2 O nanowire on Cu foil present the best hydrophobic activity without any organic additives. • The configurations and surface energies both have impacts on the excellent hydrophobic performance. [ABSTRACT FROM AUTHOR]

A free‐standing film of manganese oxide/poly(3,4‐ethylenedioxythiophene):poly (styrene sulfonate)/ carbon nanotubes (MnO2/PEDOT:PSS/CNTs) is obtained and directly applied as self‐supporting electrode of supercapacitors. CNTs (modified by ionic liquid) are homogeneously wrapped by conducting polymer PEDOT:PSS. The presence of PEDOT:PSS prevents ultrathin MnO2 nanosheets from restacking as well as promotes them vertical growth and uniform distribution on the surface of PEDOT:PSS/CNTs. The MnO2/PEDOT:PSS/CNTs hybrid electrode which possesses coaxial nanocable structure exhibits significant improvement both in specific capacitance and conductivity compared with CNTs or MnO2/CNTs electrodes. This specific hybrid structure greatly accelerates electrons transport. The specific capacitance of MnO2/PEDOT:PSS/CNTs electrode is 533 Fcm−3 at the current density of 1 mAcm−2, while the specific capacitance values of CNTs and MnO2/CNTs electrodes at the same current density only show 15 and 150 Fcm−3, respectively. The as‐fabricated MnO2/PEDOT:PSS/CNTs hybrid film also exhibits excellent rate capability and cycle stability. For example, the hybrid film shows a specific capacitance of 265 Fcm−3 at current density of 20 mAcm−2, and the high capacitance retention ratio of 129% is achieved after 20000 cycles. Due to its excellent electrochemical properties and good flexibility, MnO2/PEDOT:PSS/CNTs self‐supporting electrode presents promising applications in flexible supercapacitors. A Self‐supporting electrode of MnO2/PEDOT:PSS/CNTs with coaxial nanocable structure shows high specific capacitance (533 Fcm−3, current density of 1 mAcm−2), excellent cycle stability (129% after 20000 cycles) and rate capability (265 Fcm−3, current density of 20 mAcm−2). PEDOT:PSS enhances the adhesion and conductivity between CNTs and MnO2 nanoflakes, it also lowers the blocking and destruction of active substrates. The homogeneous and vertical growth of ultra‐thin MnO2 nanosheets on the surface of PEDOT:PSS/CNTs realized the effective charge transfer both in radial and axial directions. [ABSTRACT FROM AUTHOR]

A novel method based on sound signals is proposed to realize realtime quantitative monitoring of abrasive belt conditions in robotic grinding system. Robotic belt grinding experiments are carried out on Inconel 718 alloy workpieces. The belt wear styles are observed under scanning electron microscope (SEM). The belt wear conditions are quantified by the grinding ability factor. During grinding process, sound signals are obtained concurrently by an omnidirectional capacitance microphone. Fast Fourier Transform (FFT) and Discrete Wavelet Decomposition (DWD) are conducted to separate the belt-condition-related sound signals from the raw signals. Then sound features are extracted to establish a novel data-driven model using Optimally Pruned Extreme Learning Machine (OP-ELM). The model is developed to predict the belt grinding ability factor. Experimental datasets are used to train and validate the established model. The results show that the grinding sound in high frequency region from 10 to 15 kHz is sensitive to the belt wear conditions, and that the OP-ELM model speedily and accurately predicts the belt grinding ability factor after optimizing the hidden layer numbers and kernel function type. Compared with experimental results, the mean absolute percentage errors (MAPE) of the predicted grinding ability factor are less than 0.4% and the maximum absolute percentage errors (MAXE) are within 14%. It is thus concluded that the proposed sound-based monitoring approach using the OP-ELM model is robust in accurately predicting the grinding belt condition despite grinding dynamics involving contact pressures. [ABSTRACT FROM AUTHOR]

ZnFe 2 O 4 (ZFO) has attracted considerable attention for supercapacitors (SCs), but its performances are severely hindered by intrinsically low electronic conductivity, relatively low mechanical stability, and severe agglomeration during the charge-discharge process. Here, a novel cotton derived active carbon fiber (ACF) with hierarchical porous architecture is used as template/scaffold, ZnFe 2 O 4 nanoparticles/active carbon fiber composites (ZFO-ACFs) are prepared, in which ZFO nanoparticles (∼20 nm) are confined into the larger nanopores (∼20 nm) of the cotton derived active carbon fiber (ACF) while the smaller nanopores (∼2.5 nm) still are preserved. The cotton derived ACF matrix not only controls the size of ZFO particles and avoids self-aggregation but also offers continuous electron pathway and rapid ion transport channel, and prevents the loss of active material (ZFO) during the electrochemical reaction. The ZFO-ACFs electrode exhibits high specific capacitance of 192 F g −1 (58.7 mAh g −1 ). Moreover, enhanced rate capability are also obtained. [ABSTRACT FROM AUTHOR]

• The BS-PT nanofibers piezoelectric sensor is successfully fabricated. • The morphology and structure of nanofibers are seriously affected by the preparation conditions. • The BS-PT nanofibers piezoelectric sensor has stable output voltage and high sensitivity. • Long-term stable performance at 200 °C shows good reproducibility and stability. BiScO 3 -PbTiO 3 (BS-PT) has the high Curie temperature and excellent piezoelectric activity, and has the potential to fabricate high-performance piezoelectric devices. However, the fabrication of one-dimensional BS-PT piezoelectric sensor remains a great challenge. Here, pure phase BS-PT nanofibers are proposed and experimentally demonstrated by optimizing the concentration of the electrospinning additive and the sintering temperature, and the interdigital electrodes are combined to assemble the sensor. The BS-PT nanofibers piezoelectric sensor can maintain a stable sensitivity above 4 V/N in the range of 10–40 Hz at 60–200 °C. In addition, it has a nearly linear output voltage as the excitation pressure increases ranging from 0.07 N to 0.55 N in the range of 160–260 °C, and the sensitivity at 220 °C is still higher than 5.4 V/N. These results highlight the BS-PT nanofibers piezoelectric sensor is promising to be used for high-temperature pressure and vibration measurements. [ABSTRACT FROM AUTHOR]

The methane dry reforming (DRM) simultaneously converts the two greenhouse gases and produces syngas (CO + H 2 ), which is being significant for both environmental and industrial consideration. Employing well-defined crystal oxides as precursors can produce Ni-based DRM catalysts with good sintering and coking resistance by enhancing the metal-support interactions. Adding basic promoters also is considered as an effective way to improve the coking resistance of DRM catalysts, although challenge remains in the control over the structure, morphology and interaction of the promoter in the catalyst. To well combine the two methods together for better catalytic performance, in this work a Ni/MgO-SiO 2 catalyst was synthesized through a facile one-pot hydrothermal process, during which Ni-phyllosilicate formed as the precursor of Ni particles and MgO promoter was generated in form of Mg-phyllosilicate. This Ni/MgO-SiO 2 had a hierarchical hollow sphere structure with large surface area (477.4 m 2 /g). Both the Ni particles (avg. 6.0 nm) and MgO promoter uniformly distributed. This hollow hierarchical catalyst performed high activity, thermal stability and coking resistance for catalytic dry reforming of methane. [ABSTRACT FROM AUTHOR]

We establish a vulnerability analytical framework of CISN, and illustrate the impact path of economic fluctuation on CISN performance. Based on this, we propose an improved cascading failure model with directed weighted network, and design five network performance indicators (i.e., relative value of cascading failure, average path length, relative value of maximal connected sub-graphs, network efficiency, and structure entropy). Taking three coal eco-industrial parks in China as cases, we simulate and compare the impacts on CISN vulnerability (i.e., equality-based, dependent-based, and nested-based CISNs) of economic fluctuation. The results indicate that the interaction between economic fluctuation and network structure is the key factor in determining system vulnerability. Concerning overall vulnerability, equality-based CISN is highest, dependent-based CISN is next, and nested-based CISN is lowest. Regarding disturbance type, the changes in the five performance indicators of the three types of CISN are more intense under energy price shocks than with declining demand. Moreover, the cascading failure scale of equality-based CISN is greatest with declining demand, while the other two kinds of CISN’s is greatest under energy price shocks. Concerning disturbance intensity, equality-based CISN shows initial value sensitivity to economic fluctuation, and nested-based CISN has the strongest tolerances for economic fluctuation. From the network performance perspective, the performance of nested-based CISN is superior to that of dependent-based and equality-based CISNs. Due to longer average path length and lower network efficiency, the failure diffusion trend of equality-based CISN shows the curve of Type-S, and the diffusion rate is smooth and slow. Contrariwise, the initial diffusion rate of dependent-based CISN is the highest, indicating that the loss of system efficiency can somewhat improve the system’s anti-risk ability. [ABSTRACT FROM AUTHOR]

Pt nanoparticles are the most frequently used catalyst for Si photocathode. Alternative catalyst based on transition metal or metal oxide as cathode catalyst is greatly desired to replace Pt. A mesoporous α-Fe 2 O 3 thin film (80 nm) was deposited on the surface of planar p-Si using a facile atmospheric pressure chemical vapor deposition (APCVD) method through pyrolysis of ferrocene. The planar Si photocathode shows a 400% enhancement in photocurrent at −1.0 V RHE and an anodic onset potential shift of 0.5 V upon deposition of surface mesoporous α-Fe 2 O 3 layer. This composite photoelectrode also shows superior photoelectrochemical performance to the Pt/planar Si photoelectrode. [ABSTRACT FROM AUTHOR]

Black scraper, Thamnaconus modestus is a filefish with high market value but the standing stock has been decreased in the past years due to the overexploiting and environmental fluctuations. Industrial culture of black scraper relieved the tense between supply and demand but at the same time brought some disease problems. In this study, we reported a mass death case of cultured Thamnaconus modestus caused by Amyloodinium ocellatum in China. The disease outbroke at temperature of 22–24 °C and the main clinical symptoms were anoxia, decreased feeding activity, reduced mobility, lost balance and subcutaneous hemorrhage. According to the observation, the trophonts of A. ocellatum were non-transparent, suborbicula and the main parasitized tissues were gill and fin, accompanying with the necrocytosis of gill lamella, and hyperplasia of fin cell. The amplification and sequencing of the ribosomal RNA gene showed the parasite was 97.41–99.92% similar with A. ocellatum. The case that amyloodiniosis only occurred in T. modestu but not in turbot cultured with the same condition, indicated the tolerance of former was lower than the latter and farmers should take more surveillance to avoid the mass fish mortality in temperate season. This is the first report about the occurrence of amyloodiniosis in the black scraper. • This is the first report about the occurrence of Amyloodinium ocellatum in the black scraper. • The report would be a good reminder for avoiding mass death during culturing of black scraper. [ABSTRACT FROM AUTHOR]