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Shock absorbers are essential in enhancing vehicle ride comfort by mitigating vibrations. However, traditional rubber shock absorbers are constrained by their fixed stiffness and damping properties, limiting their adaptability to varying loads and thus affecting the ride comfort, especially under extreme road conditions. Shape Memory Alloys (SMAs), known for their intelligent material properties, offer a unique solution by adjusting stiffness and damping in response to temperature changes or strain rates, making them ideal for advanced vibration control applications. This study builds upon the Auricchio constitutive model to propose an enhanced SMA hyper-elastic constitutive model that accounts for different loading rates. This new model elucidates the impact of loading rates on the stiffness and damping characteristics of SMAs. Additionally, we introduce an innovative circular rubber-based SMA composite vibration reduction structure. Through a parameterized model and finite element simulation, we comprehensively analyze the stiffness and damping properties of the composite damper under various loading rates and harmonic excitations. Our findings suggest a novel approach to improving the vehicle ride comfort, offering significant potential for engineering applications and practical value. [ABSTRACT FROM AUTHOR]

The constitutive model and modulus parameter equivalence of shape memory alloy composites (SMAC) serve as the foundation for the structural dynamic modeling of composite materials, which has a direct impact on the dynamic characteristics and modeling accuracy of SMAC. This article proposes a homogenization method for SMA composites considering interfacial phases, models the interface stress transfer of three-phase cylinders physically, and derives the axial and shear stresses of SMA fiber phase, interfacial phase, and matrix phase mathematically. The homogenization method and stress expression were then used to determine the macroscopic effective modulus of SMAC as well as the stress characteristics of the fiber phase and interface phase of SMA. The findings demonstrate the significance of volume fraction and tensile pre-strain in stress transfer between the fiber phase and interface phase at high temperatures. The maximum axial stress in the fiber phase is 705.05 MPa when the SMA is fully austenitic and the pre-strain increases to 5%. At 10% volume fraction of SMA, the fiber phase's maximum axial stress can reach 1000 MPa. Ultimately, an experimental verification of the theoretical calculation method's accuracy for the effective modulus of SMAC lays the groundwork for the dynamic modeling of SMAC structures. [ABSTRACT FROM AUTHOR]

Variations with respect to perspective, lighting, weather, and interference from dynamic objects may all have an impact on the accuracy of the entire system during autonomous positioning and during the navigation of mobile visual simultaneous localization and mapping (SLAM) robots. As it is an essential element of visual SLAM systems, loop closure detection plays a vital role in eradicating front-end-induced accumulated errors and guaranteeing the map's general consistency. Presently, deep-learning-based loop closure detection techniques place more emphasis on enhancing the robustness of image descriptors while neglecting similarity calculations or the connections within the internal regions of the image. In response to this issue, this article proposes a loop closure detection method based on similarity differences between image blocks. Firstly, image descriptors are extracted using a lightweight convolutional neural network (CNN) model with effective loop closure detection. Subsequently, the image pairs with the greatest degree of similarity are evenly divided into blocks, and the level of similarity among the blocks is used to recalculate the degree of the overall similarity of the image pairs. The block similarity calculation module can effectively reduce the similarity of incorrect loop closure image pairs, which makes it easier to identify the correct loopback. Finally, the approach proposed in this article is compared with loop closure detection methods based on four distinct CNN models with a recall rate of 100% accuracy; said approach performs significantly superiorly. The application of the block similarity calculation module proposed in this article to the aforementioned four CNN models can increase the recall rate's accuracy to 100%; this proves that the proposed method can successfully improve the loop closure detection effect, and the similarity calculation module in the algorithm has a certain degree of universality. [ABSTRACT FROM AUTHOR]

Orthogonal antisymmetric composite laminates embedded with shape memory alloys (SMAs) wires have the potential to improve the sound quality of vibro-acoustics by taking advantage of the special superelasticity, temperature phase transition, and pre-strain characteristics of SMAs. In this research, space discretion and mode decoupling were employed to establish a vibro-acoustic sound quality model of SMA composite laminates. The association between the structural material parameters of SMA composite laminates and the sound quality index is then approached through methodologies. Numerical analysis was implemented to discuss the effects of SMA tensile pre-strain, SMA volume fraction, and the ratio of resin-to-graphite in the matrix on the vibro-acoustic sound quality of SMA composite laminates within a temperature environment. Subsequently, the sound quality test for SMA composite laminates is thus completed. The theoretically predicted value appears to agree well with the experimental outcomes, which validates the accuracy and applicability of the dynamic modeling theory and method for the sound quality of SMA composite laminates. The results indicate that attempting to alter the SMA tensile pre-strain, SMA volume fraction, and matrix material ratio can be used to modify loudness, sharpness, and roughness, which provides new ideas and a theoretical foundation for the design of composite laminates with decent sound quality. [ABSTRACT FROM AUTHOR]

Urban road facilities are typically shared by heterogeneous traffic, such as cars, buses, and bicycles. This paper investigates the car and bicycle traffic at the network level by extending the 3D-MFD model to the car-bicycle network. Statistical 3D-MFDs for the car-bicycle traffic are proposed and empirically estimated for three selected networks in Shanghai. Simulation-based 3D-MFDs are used to determine the network bicycle capacity and validate statistical 3D-MFDs. Estimation results quantify negative marginal effects of car and bicycle density on network car speeds, and confirm the negative effect of bi-modal speed difference on bicycle traffic. When looking into the predicted results of 3D-MFDs, the maximum bi-modal production changes with the accumulation of bicycles, indicating car-bicycle interactions within the network. Few empirical observations are in the optimum operation regime, which indicate the potential of improving the multi-modal networks. Findings of this study can benefit network designs and traffic operations, such as adjusting separation types, implementing stricter bicycle management, and extending bicycle priority in certain areas. [ABSTRACT FROM AUTHOR]

This study presents a 3D pick-rock contact calculation method for conical picks, aiming to develop a predictive method with high accuracy and lithological tolerance for peak cutting force (PCF). The method is based on the projection profile method and D. L. Sikarskie stress distribution function. By integrating Griffith’s theory with rock damage constitutive model, the energy relationship between the rock fracturing process and crack propagation process is analyzed. Furthermore, in order to accurately correct the PCF, the energy correction function (C-Kf) is proposed to calculate the damage intensity index (Ke), which accounts for the relationship between rock brittleness and rock damage elastic–plastic energy. To validate the method, it is compared with full-scale cutting tests and three existing models, and statistical analysis confirms its high lithological tolerance and accuracy, the present model has the highest R2 of 0.90404, which is at least 12.5% higher relative to the mainstream models. Moreover, incorporating Ke into the method further enhances its predictive capability. [ABSTRACT FROM AUTHOR]

Singlet oxygen (1O 2) is a highly effective reactive species in selectively oxidizing organic pollutants. However, it is still challenging to rationally design robust catalysts for the selective generation of 1O 2. Herein, the coordination and engineering architecture of the foam board-like CoSe 2 alloy were facilely constructed through a green solvent-free method and displayed almost 100% 1O 2 production selectivity. The CoSe 2 alloy showed excellent catalytic ability for the efficient and fast removal of organic pollutants via peroxymonosulfate (PMS) activation compared with previously reported cobalt-based catalysts. The CoSe 2 /PMS system exhibited strong resistance for a broad pH range (3.0–11.0) and various coexisting inorganic ions owing to the advantage of the strong bonding of Co-Se in CoSe 2 alloy. Mechanism studies revealed that 1O 2 was the only reactive oxygen species in the CoSe 2 /PMS system. Theoretical calculations demonstrated that Co was the dominant adsorption site for PMS in CoSe 2 , and the production pathway of 1O 2 was PMS* → *OH → *O → 1O 2. In addition, it was proved that *OH and *O served as the rate-determining steps for the formation of 1O 2 by PMS activation on CoSe 2 alloy. These findings provide a rational strategy for preparing a series of low-cost transition metal-based alloy catalysts for PMS activation to achieve high-efficiency 1O 2 production in the elimination of organic pollutants. [Display omitted] • The foam board-like CoSe 2 alloy was facilely fabricated through a green solvent-free method. • CoSe 2 exhibited excellent catalytic performance for PMS activation. • The CoSe 2 /PMS system achieved almost 100% 1O 2 production selectivity. • *OH and *O served as the rate-determining steps for the formation of 1O 2. • 100% sulfadiazine was stably removed via a continuous flow reactor in 6 h. [ABSTRACT FROM AUTHOR]

Urban road traffic is one of the primary sources of carbon emissions. Previous studies have demonstrated the close relationship between traffic flow characteristics and carbon emissions (CO2). However, the impact of dynamic traffic distribution on carbon emissions is rarely empirically studied on the network level. To fill this gap, this study proposes a dynamic network carbon emissions estimation method. The network-level traffic emissions are estimated by combining macroscopic emission models and recent advances in dynamic network traffic flow modeling, namely, Macroscopic Fundamental Diagram. The impact of traffic distribution and the penetration of battery electric vehicles on total network emissions are further investigated using the Monte Carlo method. The results indicate the substantial effect of network traffic distribution on carbon emissions. Using the urban expressway network in Ningbo as an example, in the scenario of 100% internal combustion engine vehicles, increasing the standard deviation of link-level traffic density from 0 to 15 veh/km-ln can result in an 8.9% network capacity drop and a 15.5% reduction in network carbon emissions. This effect can be moderated as the penetration rate of battery electric vehicles increases. Based on the empirical and simulating evidence, different expressway pollution management strategies can be implemented, such as petrol vehicle restrictions, ramp metering, congestion pricing, and perimeter control strategies. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes an underwater semi-active composite anechoic coating with periodic subwavelength piezoelectric arrays to broaden the low-frequency absorption bandwidth and improve the absorption coefficient. Based on the effective medium method, the dual equivalent properties for the volume density and Young's modulus of the equivalent thin-plate interlayer are computed. Then, a complete two-dimensional theoretical model for oblique incidence is established by combining the shunt damping technique and wave propagation theory in layered media. On the premise of strictly satisfying the two preconditions of subwavelength assumption and stratified convergence criteria, the correctness and effectiveness of the present model are confirmed by successively according to the finite element simulation results, experimental data, and theoretical predictions. At last, change regulations of seven critical parameters on the sound absorption characteristics of the present coating are investigated to reveal the multiple energy dissipation mechanisms of the overburden in the whole research frequency band. [ABSTRACT FROM AUTHOR]

Inappropriate cruising speed, such as speeding, is one of the major contributors to the road safety, which increases both the quantitative number and severity of traffic accidents. Previous studies have indicated that traffic congestion is one of the primary causes of drivers’ frustration and aggression, which may lead to inappropriate speed choice. In this study, the large taxi floating car data (FCD) was used to empirically evaluate how traffic congestion-related negative moods, defined as state aggressiveness, affected drivers’ speed choice. The indirect effect of traffic delay on the cruising speed adjustment through the state aggressiveness was assessed through the mediation analysis. Furthermore, the moderated mediation analysis was performed to explore the effect of driver type, value of time, and working duration on the mediation role of state aggressiveness. The results proved that the state aggressiveness was the mediator of the relationship between travel delays and driving speed adjustment, and the mediation role was different across various driver types. As compared to the aggressive drivers, the normal drivers and the steady drivers tended to behave more aggressively after experiencing non-recurrent congestion during the early stage of the trips. When the value of time was high, steady drivers were more likely to adjust their speed choice although the effect was not statistically significant for other driver types. The validation results indicated that the speed model incorporating state aggressiveness could better predict the travel time than the traditional speed model that only considering the specific expected speed distribution. The prediction results for the manifest indicators of state aggressiveness, such as the maximum speed and the speed deviation, also demonstrated a reasonable reflection of the field data. [ABSTRACT FROM AUTHOR]

• Coral reef-like FeS 2 /C cs was prepared by a one-step solvothermal method. • FeS 2 in situ grew on the surface of waste corn stalks-derived carbon (FeS 2 /C cs). • FeS 2 /C cs exhibited a superior ability for activating PMS to degrade OTC. • SO 4 − and OH were identified as the major radicals for attacking OTC. • Toxicity of OTC could be effectively reduced via the FeS 2 /C cs + PMS system. Over the past few decades, organic pollution such as tetracyclines and dyes has caused harm to the environment, biology, and human health. Therefore, developing a green and efficient method for organic pollutant removal is urgent. Herein, a coral reef-like FeS 2 /C cs was successfully constructed by one-step solvothermal growth of FeS 2 on waste corn stalks-derived carbon. The as-prepared FeS 2 /C cs catalyst exhibited much better performance in activating peroxymonosulfate (PMS) for removing organic pollutants than the other candidates previously reported. Almost 100 % of oxytetracycline (OTC) could be degraded within 20 min. Various factors like PMS concentration, catalyst dosage, initial pH values, and temperature that influenced the degradation process were then investigated. Through quenching experiments and electron paramagnetic resonance (EPR), O 2 −, 1O 2 , SO 4 − and OH were determined to be involved in attacking OTC, in which SO 4 − play a major role and OH acted as the secondary role. Subsequently, degradation pathways of OTC were rationally proposed. Toxicity simulations demonstrated that the toxicity of OTC could be effectively reduced after degradation. Universal experiments showed that FeS 2 /C cs + PMS system could also effectively degrade other typical tetracyclines and dyes, such as tetracycline (TC, ∼100 %), chlortetracycline hydrochloride (CTC, ∼100 %), methylene blue (MB, ∼83 %) and rhodamine B (RhB, ∼95 %). Moreover, the FeS 2 /C cs could remain high catalytic activity in five cycles test. This study provides a green and efficient method for organic pollution removal and technical guidance for analyzing its environmental toxicology. [ABSTRACT FROM AUTHOR]

• Fine CoFe 2 O 4 was in-situ fabricated on biomass waste-derived porous carbon framework. • CoFe 2 O 4 /C exhibited large surface area of 733.1 m2/g and presented rich oxygen vacancies. • CoFe 2 O 4 /C catalysts can directly activate PMS to efficiently remove four typical quinolones. • ∼94.8% CIP, ∼96.8% OFL, ∼100% LEV, ∼86% NOR can be efficiently degraded in 12 min. • DFT calculations elucidated the possible adsorption behavior and activation mechanism. Rational design of the low-cost, highly efficient and easily recyclable catalyst to directly activate peroxymonosulfate (PMS) is crucial for the efficient removal of organic pollutants in the sewage treatment. Herein, hyperdispersed CoFe 2 O 4 spinel nanoparticles were successfully in-situ fabricated on biomass-derived 3D porous carbon framework (C) by the facile one-step solvothermal method (CoFe 2 O 4 /C). These as-prepared CoFe 2 O 4 /C exhibit superior performance in the Fenton-like removal of four quinolones by the combination of experimental work and theoretical calculation. Experimental results prove that CoFe 2 O 4 /C catalyst can directly activate PMS to efficiently remove four types of quinolones in 12 min without the external energy consumption. The characterization results show that hyperdispersed CoFe 2 O 4 (18.0 ± 5.0 nm) nanoparticles are uniformly anchored on the matrix of C, exhibit a large specific surface area of 733.1 m2/g, and present rich oxygen vacancies (O vs), thus exposing more reactive sites and generating more reactive oxygen species (ROS). In CoFe 2 O 4 /C + PMS system, ∼97.5% of ciprofloxacin (CIP) is removed within 12 min, which is far superior to other candidates previously reported. Other quinolones (e.g., ∼96.8% of ofloxacin (OFL), ∼100% of levofloxacin (LEV), and ∼86.4% of norfloxacin (NOR)) can also be efficiently degraded under the same conditions. Based on quenching experiments, electron spin resonance spectroscopy (ESR), and density functional theory (DFT) calculations, these superior activities are mainly due to the free radical (SO 4 ·-, ·OH, and ·O 2 –) and non-free radical (1O 2), whereas SO 4 ·- and ·OH are the major reactive oxygen species. In addition, these CoFe 2 O 4 /C catalysts remain stable even after five cycles. Subsequently, degradation pathways are rationally proposed. This work provides a feasible and universal strategy for the direct activation of PMS in wastewater treatment. [ABSTRACT FROM AUTHOR]

As an extension of conventional gradient, anti-symmetric oblique coupling gradient has a superior modal modification ability on composite laminates embedded with pre-strained shape memory alloys (SMA) wires, which is beneficial to suppress modal resonance of composite laminates in the thermal environment. This paper presents an anti-symmetric oblique coupling gradient model of SMA along the thickness direction. That is, the gradient model of SMA wires' orientation and the positive and negative gradient model of SMA volume fraction. Considering the internal force of composite laminates composed of the pre-strain recovery force of SMA and the thermal expansion force of the substrate, the free vibration equation of composite laminates with additional internal forces energy is derived from first-order shear plate theory and Hamilton principle. The influence of coupling gradient parameters on the thermal modal performance of SMA composite laminates is analyzed and verified by experiments. The proposed anti-symmetric oblique coupling gradient SMA wires' distribution form effectively exerts the recovery stress generated by SMA tensile pre-strain, i.e., effectively improves the stiffness and critical buckling temperature. Coupling gradient distribution broadens the frequency modulation range, which makes the fine regulation of the natural frequency and critical buckling temperature feasible. [ABSTRACT FROM AUTHOR]

• It is a sustainable strategy to fabricate two-dimensional materials by renewable precursors. • This will be more difficult in aqueous solution due to the isotropy growth. • We achieve an aqueous solution phase synthesis of semiconductive 2D nanosheets by using renewable carbohydrate. • They can be used in photocatalytic disinfection, pollution degradation and Cr(IV) reduction. • They exhibit remarkable activity and high charge transfer efficiency. Two-dimensional (2D) materials are important materials in environmental science and engineering. They have been widely used in environmental treatments. However, most of the 2D materials are obtained and synthesized from minerals. The sources are not very environmental-friendly. In this regard, it is a sustainable strategy to fabricate 2D materials by renewable precursors like glucose in biomasses. However, synthesis of 2D materials from glucose in water is still a great challenge mainly because of isotropy growth. Herein, we achieve an aqueous solution-phase synthesis of semiconductive 2D nanosheets by using renewable carbohydrates via hydrothermal method. Previously, glucose tend to form irregular or spherical particles in hydrothermal solution due to isotropy growth. In this work, the carbohydrate of glucose can be converted into hydrothermal carbonation carbon (HTCC) nanosheets in the presence of ethylenediamine and Fe3+/Fe2+/Co2+/Ni2+ ions in water. Firstly, a Maillard reaction occurs to activate sp3-sp2 conversion of carbon to form aromatic intermediates. Then, the metal ions will trigger the formation of the HTCC nanosheets. The thickness of the nanosheets is c.a. 2–8 nm. Compared with bulk HTCC, the nanosheets exhibit dramatical enhancement. The pure bulk HTCC suffers from very poor charge transfer efficiency, which does not has obvious activiity in photocatalytic disinfection and pollution degradation. By contrast, as a 2D materials, the HTCC nanosheet exhibits excellent charge transfer efficiency at the direction perpendicular to its surface, which exhibits remarkable activity in photocatalytic disinfection, pollution degradation, and Cr(IV) adsorption and reduction. As a new method for the synthesis of 2D material in water, this method will lead to the development of a new generation of carbon-based 2D materials. [ABSTRACT FROM AUTHOR]

The interest of this article lies in the sound radiation of shape memory alloy (SMA) composite laminates. Different from the traditional method of avoiding resonance sound radiation of composite laminates by means of structural parameter design, this paper explores the potential of adjusting the modal peak of the resonant acoustic radiation by using material characteristics of shape memory alloys (SMA), and provides a new idea for avoiding resonance sound radiation of composite laminates. For composite laminates embedded with pre-strained SMA, an innovation of vibration-acoustic modeling of SMA composite laminates considering pre-stain of SMA and thermal expansion force of graphite-epoxy resin is proposed. Based on the classical thin plate theory and Hamilton principle, the structural dynamic governing equation and the frequency equation of the laminates subjected to thermal environment are derived. The vibration sound radiation of composite laminates is calculated with Rayleigh integral. Effects of ambient temperature, pre-strain, SMA volume fraction, substrate ratio, and geometrical parameters on the sound radiation were analyzed. New laws of SMA material and pre-strain characteristics on sound radiation of composite laminates under temperature environment are revealed, which have theoretical and engineering functional significance for vibration and sound radiation control of SMA composite laminates. [ABSTRACT FROM AUTHOR]

A gradient composite laminate that was composed of two-phase fibers, a shape memory alloy (SMA), and graphite was prepared to investigate modal performance and improve vibration behavior. The stress-strain relation of the single-layer composite plates was derived from Kirchhoff thin plate theory and the material constitutive of the SMA. A gradient distribution model and the eigenvalue equations of gradient composite laminates were developed. The influence of the fiber component content gradient distribution, pre-strain, the two-phase fiber volume fraction, and geometric parameters on the modal performance was analyzed. This study provides a method to avoid the structural resonance of composite laminates that are embedded with an SMA through the gradient distribution of two-phase fiber content that leads to the interaction of the material properties. [ABSTRACT FROM AUTHOR]

This paper proposes a new method to estimate bicycle accessibility for various trip purposes based on a massive dockless bike-sharing dataset in Shanghai, China. Specifically, a Dirichlet multinomial regression topic model (DMR model) is applied to identify bicycle trajectories' trip purposes, simultaneously considering arrival time and drop-off location. Based on obtained trip purposes, we estimate impedance functions using a negative exponential function. Finally, based on estimated impedance functions, two cases of bicycle accessibility for two different purposes - restaurant and hospital - are presented in Shanghais central area. The results show that almost 90% of bicycle trips are less than 30 min or 5 km. Although the difference between the impedance functions between various trip purposes is not significant, we find that trip purposes of "Work and School" have the highest travel impedance for bicyclists. Cyclists in Shanghai accept longer bicycle travel times for leisure (e.g., shopping) than for commuting (e.g., work or school). [ABSTRACT FROM AUTHOR]

[Display omitted] • Fine-grained CoFe 2 O 4 nanoparticles are facilely anchored on porous carbon. • Porous carbon boosts the mass transfer efficiency and prevents Co and Fe leaching. • CoFe 2 O 4 @PC facilitates the simultaneous removal of TC and As(III) via PMS activation. • Radical and nonradical pathways contribute to the oxidation of TC. • The degradation pathways and toxicity analysis of TC are proposed. The coexistence of tetracycline (TC) and arsenite (As(III)) in livestock wastewater threatens public health, and the heterogeneous Fenton-like system is a practical approach for the simultaneous removal of TC and As(III). In this work, fine CoFe 2 O 4 nanoparticles are facilely anchored on heretically porous carbon (CoFe 2 O 4 @PC) via a microwave-assisted calcination method and used for eliminating TC and As(III) via peroxymonosulfate (PMS) activation. The CoFe 2 O 4 @PC/PMS system exhibits excellent performance in the simultaneous removal of 96% of 10 mg/L TC and 86% of 50 μM As(III) within 30 min, whereas the porous carbon can boost the mass transfer efficiency and protect CoFe 2 O 4 against Co and Fe ions leaching. The CoFe 2 O 4 @PC/PMS system maintains satisfactory activity and stability in a broad pH range (3–11) and anti-interference capacity (anions, humic acid and water matrices). Meanwhile, the CoFe 2 O 4 @PC with the strong magnetic property was readily recovered from the reaction solution. Moreover, the cooperation of radical (·OH, ·SO 4 - and ·O 2 –) and nonradical (1O 2) pathways was documented to play critical roles in enhancing the oxidation of TC and As(III), which effectively reduces the toxicity of degradation intermediates. This work offers a facile strategy for constructing spinel-based catalysts and opens a broad prospect for removing TC and As(III) in livestock wastewater. [ABSTRACT FROM AUTHOR]

Taxis provide a type of on-demand mobility service in urban transportation. There are growing concerns regarding the level of service of taxis in satisfying residents' mobility demand. However, the mismatch between demand and supply of taxi services has not been resolved even with the introduction of app-based vehicle services. In this study, three indicators are constructed using the Shanghai taxi global positioning system (GPS) dataset to reveal the spatial–temporal mismatch pattern. The issue is further analyzed via a case study, in which seven regions with frequent mismatch patterns are identified in the time period from 21:00 to 22:00. Then, a multinomial logistic regression model is employed to identify the demographic and built-environment factors contributing to the taxi mismatch problem. The study results show that population density, residential areas, the number of points of interest, and road density have significant relationships with the taxi undersupply. In contrast, the areas of commercial lands, as well as the other two transportation-related factors, that is, the number of bus stops and the distance to nearest subway station, are observed to be statistically significant for both "oversupply" and "undersupply" conditions. This study provides valuable insights for identifying mismatch patterns and interpreting the mismatch problem as a function of spatially explicit factors that are of great use for urban governance, especially in the improvement of taxi efficiency, taxi management, and urban planning. [ABSTRACT FROM AUTHOR]

The performance of near-field acoustic holography (NAH) with a sparse sampling rate will be affected by spatial aliasing or inverse ill-posed equations. Through a 3D convolution neural network (CNN) and stacked autoencoder framework (CSA), the data-driven CSA-NAH method can solve this problem by utilizing the information from data in each dimension. In this paper, the cylindrical translation window (CTW) is introduced to truncate and roll out the cylindrical image to compensate for the loss of circumferential features at the truncation edge. Combined with the CSA-NAH method, a cylindrical NAH method based on stacked 3D-CNN layers (CS3C) for sparse sampling is proposed, and its feasibility is verified numerically. In addition, the planar NAH method based on the Paulis–Gerchberg extrapolation interpolation algorithm (PGa) is introduced into the cylindrical coordinate system, and compared with the proposed method. The results show that, under the same conditions, the reconstruction error rate of the CS3C-NAH method is reduced by nearly 50%, and the effect is significant. [ABSTRACT FROM AUTHOR]

Green and highly selective synthesis of organonitrogen chemicals (ONCs) using the renewable energy source biomass over noble-metal free solid catalysts under common room temperature and pressure conditions is still a major challenge. Here, we report a sustainable electrochemical method for selective synthesis of several valuable ONCs with high yields using biomass-derived furanic aldehydes over greenly fabricated TiS2 nanosheets through a facile synthesis. Based on a range of characterization techniques including high-resolution transmission electron microscopy and X-ray absorption fine structure, a well-defined structure of the TiS2 nanosheets (3.86 nm with 1T phase) was constructed. These as-prepared catalysts were applied to the electrochemical reductive amination (ERA) of three biomass-derived aldehydes, i.e. furfural (FF), 5-methylfurfural (MF) and 5-hydroxymethylfurfural (HMF), and exhibited superior performance whereby over 95% conversion of each furanic aldehyde and nearly perfect selectivity of ONCs were achieved. TiS2 nanosheets, in particular, exhibited a marked ∼2-fold increase in conversion (∼49%) compared with the monometallic Ti electrode. Besides, the reaction kinetics and rational pathway were also studied. In addition, these exfoliated TiS2 nanosheets maintained high durability over 6 h, providing a promising and versatile route for the sustainable upgrading of biomass-derived sources. [ABSTRACT FROM AUTHOR]

Aiming at the problem of automatic depth control for Remotely Operated Vehicle (ROV) under complex disturbed environment, this paper designs a control scheme used the improved Linear Active Disturbance Rejection Controller (LADRC) based on nutcracker optimization algorithm (NOA). Firstly, in order to solve the disturbance problem in the depth control process of ROV under complex disturbed environment, the LADRC is applied to the depth control of ROV to improve the disturbance rejection capability of the system. After that, due to the difficulty and uncertainty of LADRC parameter tuning, the global search capability of nutcracker optimization algorithm is used to optimize the LADRC controller. It realizes the automatic tuning of LADRC parameters, thus realizes the fast and high-accuracy depth control. Finally, the simulation and experimental verification are completed. The overshooting amount of the NOA-LADRC control scheme in the depth control of ROV is almost zero, the control accuracy and disturbance rejection capability are improved by about 50%. • The disturbance rejection capability and control accuracy of depth control for ROV are improved by NOA-LADRC scheme. • Automatic tuning of controller parameters is realized by improving nutcracker optimization algorithm. • The effectiveness and superiority of the proposed control scheme are verified by simulation and experiments. [ABSTRACT FROM AUTHOR]

Honeycomb core sandwich plates are widely used as a lightweight, high-strength sound insulation material. However, they do not perform well in specific frequency bands. Acoustic metamaterials can break the law of mass in specific frequency bands and have high sound transmission loss (STL); however, the resonance frequency is difficult to regulate. To solve this problem, this paper first proposes an infinitely large metamaterial honeycomb core sandwich plate, which can generate newly tuned piezoelectric resonance frequencies, and we study its STL. The structure has piezoelectric patches arranged in sub-wavelength arrays with inductance shunting circuits that are elastically connected to both sides of the honeycomb core sandwich plate. The effective dynamic mass density and effective dynamic bending stiffness of the metamaterial plates were obtained using the effective medium (EM) method. A theoretical model for the numerical calculation of oblique STL and diffuse-field STL was established by the structural bending wave method. The finite element simulation method was used to verify that the metamaterial plates can generate three peaks at 1147 Hz, 1481 Hz and 1849 Hz in oblique or diffuse-field STL curves, which reached 57 dB, 86 dB and 63 dB, respectively, and are significantly better than the plate rigidly connected with piezoelectric sheets and the bare plate with the same mass. In order to better understand the characteristics of STL, the explicit functions of the resonance frequencies were derived. Key influencing factors were analyzed, and the regulation law of new piezoelectric resonance frequencies was clarified. [ABSTRACT FROM AUTHOR]

[Display omitted] • The enantioselective Michael addition of malonates with unsaturated ketones. • Catalyzed by samarium amide Sm[N(SiMe 3) 2 ] 3 together with the chiral phenoxy-functionalized amino alcohol proligands. • The products with good group tolerance, mostly in high to excellent yields (85–98%) and good to excellent ee values (50– >99%). • A possible mechanism was proposed. A combination of rare-earth metal amides RE[ N (SiMe 3) 2 ] 3 and chiral phenoxy-functionalized amino alcohol proligands was developed to realize the enantioselective Michael addition of malonates with unsaturated ketones. The reactions catalyzed by samarium amide Sm[ N (SiMe 3) 2 ] 3 were performed best together with the chiral proligand H 3 L1 (H 3 L1 = 2,4-di- tert -butyl-6-((((1 S ,2 R)-2-hydroxy-1,2-diphenylethyl) amino)methyl)phenol) in DCE with good group tolerance, mostly in high to excellent yields (85–98 %) and good to excellent ee values (50− >99 %). The possible mechanism was also proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rational design and synthetic strategies of multifarious SMOs are summarized. • Intrinsic relationship between SMO's structure and catalytic properties is analyzed. • The photocatalytic mechanism of SMOs for antibiotics degradation is revealed. • Challenges and prospects of SMOs for antibiotics degradation are highlighted. Due to the permanent harm to human health and ecosystem balance, antibiotic pollution in water has become an important direction of current environmental governance. Spherical metal oxides (SMOs) have been frequently utilized as effective heterogeneous photocatalysts for the efficient degradation of antibiotics due to their unique properties (e.g., strong light absorption ability, high separation efficiency of photo-generated electron-hole pairs, and good catalytic activity). This review will firstly focus on summarizing the rational design and synthesis of SMOs with various tuned microstructures such as hollow, porous shell, yolk shell, core shell, and nanoflowers. These structures can expose more active sites, achieve a higher utilization rate of light, enhance the mass transfer efficiency and improve the effective diffusion of reactive oxygen species (ROS). Secondly, this review will mainly analyze the intrinsic relationship between the structure of SMOs and their photocatalytic property, the ability to generate ROS, and the degradation pathway for antibiotics. Moreover, the photocatalytic mechanisms and recent progress of different SMO catalysts for degrading typical antibiotics are compared in detail. Finally, challenges and prospects of future direction in the development of SMOs for antibiotic degradation are reviewed. It is expected to provide a rational design of SMO catalysts for efficient photocatalytic degradation of environmental pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiSi intermetallic compounds (IMCs) were prepared via an arc-melting method. • The NiSi IMCs show high activity for hydrogenation and oxidation of cinnamaldehyde. • The NiSi IMCs can be used for 5 runs without deactivation for both transformations. • The Si vacancy and NiO x species account for the dual functions of the NiSi IMCs. • The IMCs structure leads to the excellent stability of the NiSi IMCs. Intermetallic compounds (IMCs) are promising catalysts for upgrading biomass-derived platform chemicals. Herein, bifunctional NiSi IMCs catalysts were developed for the hydrogenation and oxidation of cinnamaldehyde (CAL). A solvent-free arc-melting method was employed for the synthesis of NiSi IMCs within 5 min. The NiSi IMCs catalysts afforded 99 % conversion of CAL and presented ∼ 71 % yield of 2-phenyl propanol and ∼ 34 % yield of benzaldehyde for the hydrogenation and base-free oxidation of CAL, respectively. Moreover, NiSi IMCs could be used for five runs without deactivation. Characterizations and theoretical calculation results indicated the formation of intermetallic structure and the existence of Si vacancy sites, which could not only facilitate the efficient hydrogenation of CAL but also expose NiO x species as catalytic centers for the oxidation of CAL, leading to the high performance and stability in both hydrogenation and oxidation process. [ABSTRACT FROM AUTHOR]

How to efficiently and fast remove the serious perniciousness of the residual antibiotics in water environment is crucial for protecting ecosystem. Herein, we reported the Fenton-like system based on layered double hydroxides (LDHs) nanosheets for direct peroxymonosulfate (PMS) activation efficient for fast removing the typical five fluoroquinolones antibiotics ciprofloxacin (CIP), norfloxacin (NOR), levofloxacin (LEV), enrofloxacin (ENR) and ofloxacin (OFL). A series of CoFe-LDHs nanosheets was one-step fabricated by integrating coprecipitation and in-situ exfoliation method. The as-obtained CoFe-LDHs nanosheets catalysts exhibit thin nanosheets (~3 nm) with high redox properties, abundant oxygen vacancies, appreciable adsorption capacity, remarkable catalytic performance and favorable stability. The variable valent state, cheap, easy-to-obtain and low-toxic Co and Fe elements were used to construct stable LDHs for efficient activation of PMS to degrade quinolone antibiotics. Among them, Co 1 Fe 1 -LDHs nanosheets exhibited the best CIP degradation efficiency of 86.9% within 12 min, which is superior to most of previous candidates. The impacts of different reaction parameters, catalyst stability, main reactive oxygen species, the main CIP degradation mechanism and rational degradation pathways were systematically studied. This work offers a feasible strategy to tune the performance of LDHs-based materials in Fenton-like system degradation of antibiotics. [Display omitted] • A series of CoFe-LDHs nanosheets were used to activate PMS to degrade quinolones. • The structure-activity relationship of CoFe-LDHs was studied. • The Co 1 Fe 1 -LDHs/PMS/CIP system could degrade 86.9% CIP within 12 min. • Degradation mechanism and pathway of ciprofloxacin was proposed. [ABSTRACT FROM AUTHOR]

• A new NAH method for low measuring sampling rate was proposed. • Feature extraction and pattern learning capability of deep learning technologies was utilized. • The frequency dimension information of the signal was fully utilized. • A data processing method for the proposed NAH was given. • The proposed NAH method was verified more accurate than the existing methods. Near-field acoustical holography (NAH) is an efficient noise diagnosis method with the deficiencies including wraparound error, which will increase when the spatial sampling rate is reduced below the minimum specified by Shannon-Nyquist theorem. Based on 3D convolutional neural network (3D-CNN) and stacked autoencoder (SAE), a method called CSA-NAH is proposed to reduce the wraparound error under sparse measuring. Subsequently, numerical calculations are carried out to illustrate the feasibility and performance of CSA-NAH. The results show that when holographic measurement point number is 64, average reconstruction error of CSA-NAH on an aluminum plate for sound pressure within 2000 Hz is 4.32%, while the latest existing methods is greater than 10%. For error in 1200 Hz~2000 Hz, the error is reduced from more than 15% of the existing methods to 5.5%. Therefore, the application of the proposed CSA-NAH can cut down the measuring cost by reducing the number of microphones without wraparound error. [ABSTRACT FROM AUTHOR]

Revealing dockless bike-sharing utilization pattern and its explanatory factors are essential for urban planners and operators to improve the utilization and turnover of public bikes. This study explores the dockless bike-sharing utilization pattern from the perspective of bike using GPS-based bike origin-destination data collected in Shanghai, China. In this paper, utilization patterns are captured by decoupling several spatially cohesive regions with intensive bike use via non-negative matrix factorization. We then measure the utilization efficiency of bikes within each sub-region by calculating Time to booking (ToB) for each bike and explore how the built environment and social-demographic characteristics influence the bike-sharing utilization with ordinary least squares (OLS) regression and geographically weighted regression (GWR) models. The matrix factorization results indicate that the shared bikes mainly serve a certain area instead of the whole city. In addition, the GWR model shows higher explanatory power (Adjusted R 2 = 0.774) than the OLS regression model (Adjusted R 2 = 0.520), which suggests a close relationship between bike-sharing utilization and the selected explanatory variables. The coefficients of the GWR model reveal the spatial variations of the linkage between bike-sharing utilization and its explanatory factors across the study area. This study can shed light on understanding the demand and supply of shared bikes for rebalancing and provide support for operators to improve the dockless bike-sharing utilization efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • SNC honeycomb carbon was prepared via a facile impregnation-microwave method. • N and S co-implanted carbon created a synergistic effect for water remediation. • Positively charged carbon sites in SNC favor providing more active sites. • The exposed active sites (pyrrolic N and thiophene S) favor the production of O 2 −. • SNC with strong hydrophilicity and conductivity facilitates Photo-PMS degradation. Reactive oxygen species (ROS) generated via peroxymonosulfate (PMS) activation is crucial for degrading toxic pollutants. Herein, the co-implantation of S and N in carbon (SNC) was facilely constructed as Fenton-like photocatalysts for water remediation. Experimental and theoretical prediction disclosed that the electron cloud density around the C atom weakens the adjacent N-O as well as S-O bond due to the fracture of the surface N/S-O bond, facilitating electron transfer and subsequently the activation of surface lattice oxygen. The electronic effect of SNC catalysts with different S and N doping amounts was later regulated, and the rational reaction mechanism of the 2SNC + PMS + light (L) system was proposed. The obtained 2SNC exposed more exposed active sites (e.g., thiophene S and pyrrolic N) to effectively activate PMS with high performance by generating dominant active species superoxide radicals (O 2 −) in water remediation. The activity surpasses the results reported previously. A degradation rate of Aspirin (Asp) was up to 95.1% and the mineralization rate of 70.6% was reached in 40 min. Besides, these fabricated 2SNC catalysts were also suitable for the degradation of other phenolic pollutants (phenol (P), bisphenol A (BPA), 2,6-dimethylphenol (DMP), and p-chlorophenol (CP)) with the removal rate of over 70% in 40 min. Furthermore, the catalyst maintained satisfactory efficiency in actual water samples. This study provides a new guideline for developing S and N co-implanted carbon for water remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The garland-like MIL-101(Fe)/MoS 2 nanosheets activated PMS to degrade SMX. • .OH and 1O 2 were the dominant ROS in the MMS-0.1/PMS/SMX system. • Sulfur vacancies and Mo6+/Mo4+ sites accelerated the cycle of Fe3+/Fe2+. • Fukui index and LC-MS fully validated the rational degradation pathway of SMX. • The non-toxicity transformation of SMX was proved by toxicity analysis. Iron-based molybdenum disulfide (Fe-MoS 2) has emerged as a Fenton-like catalyst for the highly efficient degradation of antibiotics, but the structure–activity relationship remains elusive. Herein, garland-like MIL-101(Fe)/MoS 2 nanosheets (MMS) with dual metal active sites (Fe and Mo) and rich sulfur vacancies were fabricated to directly activate peroxymonosulfate (PMS) for fast degradation of different organic pollutants (phenols, dyes and drugs), even in real water bodies. The MMS exhibited extremely fast catalytic rate constant of 0.289 min−1 in the degradation of sulfamethoxazole (SMX), which was about 36 and 29 times that of single MoS 2 (0.008 min−1) and MIL-101(Fe) (0.01 min−1). Moreover, MMS with good stability and reusability could reach 92% degradation of SMX after 5 cycles. Quenching experiments and electron spin resonance (ESR) tests revealed that hydroxyl radicals (. OH) and singlet oxygen (1O 2) were the dominant reactive oxygen species (ROS) for SMX degradation. The integration of experimental works, characterization techniques and density functional theory (DFT) calculations unraveled that the formation of sulfur vacancies in MMS catalyst could expose more Mo sites, improve the charge density and boost the electron transfer, which was conducive to accelerating the Fe3+/Fe2+ cycle for enhancing the activation of PMS. Finally, the C-N, N-O, S-N, C-O and C-S bonds of SMX were easily attacked by ROS to generate the nontoxic intermediates in the MMS/PMS/SMX system. This study offers a new approach to designing high-performance Fe-MoS 2 catalysts for the removal of organic pollutants. [ABSTRACT FROM AUTHOR]

Abstract: Background and Aim: The aim of our study was to investigate the immunomodulatory effect and short‐term efficacy and long‐term prognosis of decompensated liver cirrhosis patients caused by hepatitis B after a double transplantation with human umbilical cord mesenchymal stem cells (hUCMSCs). Methods: Fifty inpatients were recruited and given the same medical treatments, receiving hUCMSCs injection intravenously. Fifty‐three patients (Group B) matched for age, sex, and baseline alanine aminotransferase, aspartate aminotransferase, albumin, total bilirubin, prothrombin time, and model for end‐stage liver disease score and Child–Pugh classification, acted as the control group. Results: Interleukin‐6 and tumor necrosis factor alpha levels markedly decreased, and interleukin‐10 level apparently increased in Group A at 2 and 4 weeks after treatment. Transforming growth factor beta in Group A increased more remarkably at 2 weeks after treatment. T4 cells and Treg cells in Group A were apparently higher than those in Group B at 2 and 4 weeks after treatment, and T8 cells and B cells were significantly lower than those in Group B. Aspartate aminotransferase levels in Group A were dramatically declining at 8 and 12 weeks after treatment. Levels of albumin, total bilirubin, and prothrombin time in Group A were apparently improved from 4 to 12 weeks after treatment. The improvements in model for end‐stage liver disease and Child–Pugh scores in Group A were notably superior to those in Group B from 4 to 36 weeks after treatment. There were no remarkable differences in the incidence of developing liver failure throughout the follow‐up period, but the mortality rate of Group A was lower than that of Group B. Conclusion: This therapeutic method may be an appropriate choice for patients with decompensated liver cirrhosis. [ABSTRACT FROM AUTHOR]

• The NCC (NiCo 2 O 4 grown on carbon) is developed as a robust photo-Fenton-like catalyst. • The synergistic effect between NC and carbon enhances the catalytic performance. • The NCC + PMS + L coupling system is universal for phenolic pollutants removal. • Degradation intermediates and removal mechanisms are identified and elucidated. Rational design of photocatalysts with the controllable structure to expose active sites is crucial to degrade phenolic pollutants. Herein, we report the in-situ synthesis of lily-like NiCo 2 O 4 nanosheets (0.95 nm) grown on waste biomass-derived carbon (abbreviated as NCC) for the highly efficient photocatalytic removal of phenolic pollutants through the integration of experiment and theory calculation. These as-fabricated NCC photocatalysts (2.29 nm) exhibit superior performance for the fast removal of phenolic pollutants (such as 4-Acetamidophenol (AP), phenol, and aspirin) in comparison with their counterpart and previously reported candidates. By using AP as a model molecule for mimicking pollutants, the photocatalytic degradation performance of NCC nanosheets is ∼ 1.3 and 1.9 times higher than that of pure NiCo 2 O 4 (NC) and porous carbon, respectively. Various factors that influenced the degradation process such as peroxymonosulfate (PMS) concentration, catalyst dosage, AP concentration, and initial pH are thoroughly investigated. The free radical quenching experiments and electron paramagnetic resonance (EPR) spectra further demonstrate the existence of SO 4 −·, ·OH, ·O 2 –, and 1O 2 in the reaction system and the ·O 2 – radical play a major role, which is also confirmed by the density functional theory (DFT) calculation. Several degradation pathways (e.g., demethylation, deacylation, hydroxylation, and ring-opening) are then proposed based on the detected intermediates. Finally, the high stability and good reusability of NCC nanosheets are confirmed via the degradation efficiency of over 85% even after five successive cycles. [ABSTRACT FROM AUTHOR]