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In the pursuit of global energy conservation and emissions reductions, utilizing beverage cans as energy-absorbing components offers potential for a sustainable economy. This study examines the impact of foam filling on the crushing behaviors and energy absorption of various types of beverage cans. Quasi-static compression tests were conducted on five geometrically sized cans filled with three densities of polyurethane foam to study their deformation modes and calculate crashworthiness parameters within the effective stroke. Results show that empty beverage cans have lower energy absorption capacities, and deformation modes become less consistent as can size increases. Higher foam density leads to increased total energy absorption, a slight reduction in the effective compression stroke, and a tendency for specific energy absorption to initially increase and then decrease. Regarding crush behavior, smaller cans transition from a diamond mode to a concertina mode, while larger cans exhibit a columnar bending mode. Next, the coupling effect of energy absorption between foam and cans was analyzed so as to reveal the design method of energy-absorbing components. The specific energy absorption of smaller cans filled with polyurethane foam is superior to that of similar empty cans. These findings provide valuable insights for selecting next-generation sustainable energy absorption structures. [ABSTRACT FROM AUTHOR]

Considering the magnetic shielding requirements of both geomagnetic field and 50 Hz power-line frequency in the complex working conditions of the power grid, an electromagnetic shielding system combining active and passive modes is proposed in this article. A three-dimensional Helmholtz coil with a magnetic shielding barrel nested inside is established by the COMSOL simulation tool, and the magnetic shielding efficiency of the system is analyzed. Comparing different materials, the simulation results indicate that permalloy alloy exhibits better shielding performance than pure iron and nickel materials. Additionally, the overall shielding efficiency of the shielding barrel increases linearly with the number of multiple layers. Under the combined active and passive electromagnetic shielding conditions, the system achieves a shielding efficiency of SE = 113.98 dB, demonstrating excellent performance in shielding both AC and DC interference magnetic fields. This study provides theoretical guidance for the construction of magnetic shielding systems in electromagnetic interference environment. [ABSTRACT FROM AUTHOR]

Developing high-performance Pt-based electrocatalysts via the functionalization of carbon carriers is an enormous challenge for their versatile electrocatalytic applications. Herein, carbonaceous (CA) supporter enriched with oxygen-species and anchored by PtNiCo nanoparticles is in-situ synthesized by a "liquid-phase calcination" (LPC) approach. As a result, PtNiCo/CA obtained in polyethylene glycol presents excellent current density in methanol oxidation reaction (MOR) (435 mAmg−1Pt), higher half-wave potential (0.92 V) in oxygen reduction reaction (ORR), and lower overpotential (377 mV) at the current density of 100 mAcm−1 in oxygen evolution reaction (OER). Furthermore, the prepared electrocatalyst shows excellent durability in MOR, ORR, and OER processes. Characterizations including in-situ infrared spectroscopy indicated that the formed M − O species and oxygen-enriched carbonaceous support is conducive to the protonation and deprotonation behaviors, thus enhancing the activity and stability of Pt active sites. Our synthetic strategy shows a potential approach for preparing high-active and long-durable Pt-based versatile electrocatalysts. • PtNiCo/carbonaceous was fabricated by an in-situ LPC approach. • Carbonaceous supporter was enriched with oxygen-containing species. • PtNiCo alloy nanoparticles were deeply anchored in CA layer. • PtNiCo/CA exhibited excellent performance in MOR, ORR and OER. [ABSTRACT FROM AUTHOR]

This review introduces an innovative technology termed "Micro-Extrusion Foaming (MEF)", which amalgamates the merits of physical foaming and 3D printing. It presents a groundbreaking approach to producing porous polymer fibers and parts. Conventional methods for creating porous materials often encounter obstacles such as the extensive use of organic solvents, intricate processing, and suboptimal production efficiency. The MEF technique surmounts these challenges by initially saturating a polymer filament with compressed CO2 or N2, followed by cell nucleation and growth during the molten extrusion process. This technology offers manifold advantages, encompassing an adjustable pore size and porosity, environmental friendliness, high processing efficiency, and compatibility with diverse polymer materials. The review meticulously elucidates the principles and fabrication process integral to MEF, encompassing the creation of porous fibers through the elongational behavior of foamed melts and the generation of porous parts through the stacking of foamed melts. Furthermore, the review explores the varied applications of this technology across diverse fields and imparts insights for future directions and challenges. These include augmenting material performance, refining fabrication processes, and broadening the scope of applications. MEF technology holds immense potential in the realm of porous material preparation, heralding noteworthy advancements and innovations in manufacturing and materials science. [ABSTRACT FROM AUTHOR]

Sorghum (Sorghum bicolor L.) has emerged as a pivotal global food crop. Consequently, it is imperative to explore sustainable and eco-friendly strategies to achieve sustainable sorghum production with a high yield. This study aimed to reveal the effects of irrigation management and nitrogen rates and their interactions on sorghum growth traits, yield and soil nitrate-N and ammonium-N accumulation to improve irrigation and nitrogen practices under drip irrigation. A 2-year (2021 and 2022) field experiment was conducted on drip-irrigated fertilized sorghum in Heilongjiang Province to investigate the effects of three lower levels of soil moisture (80% (HI), 70% (NI), and 60% (LI) of field capacity) with four nitrogen rates at 225, 150, 75 and 0 kg/ha (designated as HN, NN, LN and WN, respectively) on sorghum growth, yield and soil nitrogen accumulation. The results indicated that irrigation management and nitrogen rate interaction had a significant effect on sorghum growth (plant height, stem diameter, leaf area index (LAI), and SPAD value), yield, aboveground biomass and 0~60 cm soil nitrogen accumulation (p < 0.05). The NNHI treatment demonstrated the highest plant height (120.9 and 121.8 cm) and LAI (2.738 and 2.645) in 2021 and 2022, and there was a significant positive correlation between plant height, LAI, and yield (p < 0.01). However, the NNNI treatment exhibited the highest yield (7477.41 and 7362.27 kg/ha) in 2021 and 2022, sorghum yield increased and then decreased with an increase in irrigation management and nitrogen rate. In addition, soil nitrate-N and ammonium-N accumulation were significantly affected by the interaction of irrigation management and nitrogen rate (p < 0.05) while irrigation management had no significant effect on the accumulation of nitrate-N and ammonium-N. Soil nitrate-N and ammonium-N accumulation increased with the increasing nitrogen rate. Although yield differences between the NNNI and HNNI treatments were not significant, the NNNI treatment with a lower soil moisture limit of 70% field capacity and a nitrogen rate of 150 kg/ha accumulated 10.4% less nitrate-N in soil than the HNNI treatment, reduced risk of nitrate nitrogen leaching. The regression analysis indicated that the optimal irrigation management and nitrogen rate management practices of 71.93% of the soil moisture lower limit and 144.58 kg/ha of nitrogen rate was an optimal strategy for favorable sorghum growth, high-yielding and low soil nitrate-N accumulation of sorghum. This study provides a scientific reference for precise water and fertilizer management in sorghum. [ABSTRACT FROM AUTHOR]

A co-sputtering process for the deposition of Fe0.8Ga0.2B alloy magnetostrictive thin films is studied in this paper. The soft magnetic performance of Fe0.8Ga0.2B thin films is modulated by the direct-current (DC) sputtering power of an FeGa target and the radio-frequency (RF) sputtering power of a B target. Characterization results show that the prepared Fe0.8Ga0.2B films are amorphous with uniform thickness and low coercivity. With increasing FeGa DC sputtering power, coercivity raises, resulting from the enhancement of magnetism and grain growth. On the other hand, when the RF sputtering power of the B target increases, the coercivity decreases first and then increases because of the conversion of the films from a crystalline to an amorphous state. The lowest coercivity of 7.51 Oe is finally obtained with the sputtering power of 20 W for the FeGa target and 60 W for the B target. Potentially, this optimization provides a simple way for improving the magnetoelectric coefficient of magnetoelectric composite materials and the sensitivity of magnetoelectric sensors. [ABSTRACT FROM AUTHOR]

To enhance the heat dissipation and mass transfer from a proton exchange membrane fuel cell (PEMFC) stack, a multi-objective topology optimization model considering structural deformation, heat transfer, mass diffusion, and gas flow process is proposed herein. The average molar concentration of oxygen and average temperature in the cathode catalyst layer (CL) are considered as the optimization objectives, and the mechanical, mass transfer, and gas flow properties are treated as constraints. The results reveal that compared with a straight gas channel, the topology-optimized configuration leads to an improvement in oxygen molar concentration by 10.36% and reduction in average temperature by 2.26 K. A higher power-dissipation constraint leads to a more complex three-dimensional channel structure with more branches. A larger structural displacement constraint results in a wider and flatter flow channel topology. The average oxygen molar concentration of topologically optimized configurations increases ranging from 5.18 to 14.96%, and the average temperature in the CL decreases about 2.2 K, compared with that of straight gas channel configurations, when the velocity at inlet varies from 0.05 to 0.3 m/s. These findings can aid in the design of PEMFCs. • Multi-objective topology optimization model for heat and mass transfer is proposed. • Constraint influences on topology optimization results are investigated. • Larger power dissipation constraint can lead more complex channel structure. • Inlet velocity effects on molar concentration and temperature are identified. [ABSTRACT FROM AUTHOR]

When tracking maneuvering targets, recurrent neural networks (RNNs), especially long short-term memory (LSTM) networks, are widely applied to sequentially capture the motion states of targets from observations. However, LSTMs can only extract features of trajectories stepwise; thus, their modeling of maneuvering motion lacks globality. Meanwhile, trajectory datasets are often generated within a large, but fixed distance range. Therefore, the uncertainty of the initial position of targets increases the complexity of network training, and the fixed distance range reduces the generalization of the network to trajectories outside the dataset. In this study, we propose a transformer-based network (TBN) that consists of an encoder part (transformer layers) and a decoder part (one-dimensional convolutional layers), to track maneuvering targets. Assisted by the attention mechanism of the transformer network, the TBN can capture the long short-term dependencies of target states from a global perspective. Moreover, we propose a center–max normalization to reduce the complexity of TBN training and improve its generalization. The experimental results show that our proposed methods outperform the LSTM-based tracking network. [ABSTRACT FROM AUTHOR]

Permeability of fibrous porous structures is a key material property for predicting the gas flow path during working conditions. A direct simulation Monte Carlo method is proposed to study the H2 gas flow in fibrous porous structures under different flow regimes of the molecular flow zone, transition zone, slip zone, and continuum zone. The effects of fibrous porous structural parameters such as porosity, fiber diameter, and variance of fiber diameter on the permeability are studied. Results show that the permeability of the continuous zone is in good agreement with that predicted by the semi-empirical formula, while the permeability of other flow regimes is larger than that predicted by the semi-empirical formula, and the deviation increases with the increase in the Knudsen number. The porosity, fiber diameter, and variance of fiber diameter have positive correlations with permeability under the full flow regimes. When the Knudsen number increases, the influence degree of porosity on the permeability gradually decreases, while the influence degree of the other parameters on the permeability increases. A new empirical formula considering the Knudsen number and structure characteristics is proposed to well predict the permeability of fibrous porous structures under the full flow regimes. [ABSTRACT FROM AUTHOR]

Understanding the behavior of nitrate in the unsaturated zone is critical for predicting groundwater nitrate pollution. Although this issue has been intensively investigated for shallow soil profiles, it remains poorly understood in deep soils. We collected soil samples up to 20 m depth under farmland and apple orchards with trees that were 16 and 22 years old (A16 and A22). We then determined soil-water content, stable isotopes (δ2H and δ18O) and nitrate content under two land use types. The stable isotopes of nitrate under two apple orchards were measured to a depth of 16 m. The mean nitrate contents in the shallow soils (0–6 m) under apple orchards (78.8 ± 87.8 mg kg−1 for A16, 180 ± 155 mg kg−1 for A22) were significantly higher than that of farmland (2.40 ± 1.56 mg kg−1) (p < 0.01), whereas the nitrate contents in the deep soils (6–20 m) were almost similar between apple orchards and farmland. Ammonium or urea-based nitrogen (N) fertilizers (30–61%) were the predominant contributors to nitrate in the shallow soil layers, followed by soil organic N and manure & sewage, whereas the soil organic N (mean 34%) was the primary source of nitrate in deep soils. Isotopic data revealed that the N transformation was controlled by nitrification, and denitrification was not apparent throughout the soil profiles. The downward transport of nitrate lagged behind soil-water. Nitrate was leached by piston flow in the vadose zone, and the nitrate from N application since the 1980 s has only infiltrated to 6 m depth. The difficulty in recharging deep soils mitigates the transport of nitrate to lower depths. The combination of water-nitrate stable isotopes provides new insights for identifying nitrate sources, transformation, and transport in the thick unsaturated zone. • Stable isotopes of water and nitrate were used to explore nitrate transport. • The nitrate hardly further transported to the deep soils (> 6 m). • The transport downward of nitrate lagged behind that of soil water. • Nitrate was pushed down by the piston flow in the vadose zones. [ABSTRACT FROM AUTHOR]

In this paper, an experimental study on mechanical properties at high temperature of a typical autoclaved aerated concrete (AAC) tested in compression is presented (compressive strength = 5 MPa and density = 600 kg/m3 at 20 °C). Parameters such as the compressive strength, strain at the peak stress, and elastic modulus are investigated, along with the stress-strain response in the thermal range 20–700 °C. The behavior of the AAC tested in this research project is different from that of normal concrete, because of a series of chemo-physical processes occurring at high temperature. Between 100 and 600 °C, the compressive strength increases and then starts decreasing (+51% at 600 °C and +10% at 700 °C compared to ambient conditions). The strain at the peak stress increases as well with the temperature similar to – but more than in – normal concrete. The stress-strain curves and the failure modes show that AAC's behavior is brittle at any temperature and that the damage inside the material increases with the temperature in such a way that the existing models for normal concrete exposed to high temperatures cannot be used in the case of AACs. Hence, a new polynomial model is proposed to properly describe the constitutive behavior of AACs at high temperature. • Experimental study on compressive propertiesof a typical autoclaved aerated concrete (AAC) at high temperature. • Compressive strength, strain at peak stress, elastic modulus, and stress-strain response are studied between 20-700 °C. • Compressive strength increases between 100-600 °C and then decreases. Strain at peak stress increases with temperature. • Failure mode is brittle. A polynomial model is proposed to describe the constitutive behavior of AACs at high temperature. [ABSTRACT FROM AUTHOR]

For traditional 12/8 bearingless switched reluctance motors (BSRMs), the coupling between torque and levitation increases the complexity of control. For the turbomachinery application, 2 degrees of freedom (DOF) BSRMs stabilized by extra 3-DOF active magnetic bearings are required. In this article, an improved BSRM with 4 rotor poles and 12 stator poles is proposed to realize 4-DOF radial levitation, and the torque dead zone is compensated because that two rotors and these poles are assemble with 15 mechanical degree shifted. The decoupling of torque and radial levitation is realized simultaneously. Moreover, the operation principle of axial reluctance force is analyzed for passive levitation in the axial direction. Various experiments were completed to verify the performance of the proposed BSRM, and the prototype achieved stable levitation of the rotor in 10 000 r/min. [ABSTRACT FROM AUTHOR]

Large-scale water transfer projects (LWTPs) have been promoted to address rising water demands around the world. Scholars have been examining various impacts of LWTPs for decades; however, there is limited research that systematically examines the literature and synthesizes impacts and lessons learned from LWTPs. By conducting a systematic literature review, we assess the impacts of LWTP implementation on communities followed by the social, political, and economic factors that shape the implementation of LWTPs. Our review indicates that LWTPs can threaten livelihood strategies, jeopardize the sustainability of traditional cultures, and disrupt communities through resettlement. These impacts are shaped by the use of water as a political mechanism, the prioritization of economic interests, and unequal participation of stakeholders. Our review goes beyond individual studies of LWTPs to highlight the importance of using an environmental justice framework to guide LWTP assessments so that these assessments can address unique contexts of individual LWTPs. [ABSTRACT FROM AUTHOR]

A generalized and facile strategy toward 2D hybrid porous carbons (2DHPCs) with various highly active functional species (e.g. Co, B, and P) is developed via 2D molecular brushes as biomimetic building blocks. The resulting 2DHPCs present superior electrochemical energy conversion and storage properties. [ABSTRACT FROM AUTHOR]

• Integrated framework of self-consistent microscopic traffic model calibration with empirical trajectory. • Macro-micro inconsistent assumption, real-world car-following scenarios, synthetic numerical simulation scenarios. • An improved multi-objective optimization algorithm for macro-micro calibration. • The novel steady state extraction methodology of traffic flow based on deep learning approaches. Calibrating microscopic car-following (CF) models is crucial in traffic flow theory as it allows for accurate reproduction and investigation of traffic behavior and phenomena. Typically, the calibration procedure is a complicated, non-convex optimization issue. When the traffic state is in equilibrium, the macroscopic flow model can be derived analytically from the corresponding CF model. In contrast to the microscopic CF model, calibrated based on trajectory data, the macroscopic representation of the fundamental diagram (FD) primarily adopts loop detector data for calibration. The different calibration approaches at the macro- and microscopic levels may lead to misaligned parameters with identical practical meanings in both macro- and micro-traffic models. This inconsistency arises from the difference between the parameter calibration processes used in macro- and microscopic traffic flow models. Hence, this study proposes an integrated multiresolution traffic flow modeling framework using the same trajectory data for parameter calibration based on the self-consistency concept. This framework incorporates multiple objective functions in the macro- and micro-dimensions. To expeditiously execute the proposed framework, an improved metaheuristic multi-objective optimization algorithm is presented that employs multiple enhancement strategies. Additionally, a deep learning technique based on attention mechanisms was used to extract stationary-state traffic data for the macroscopic calibration process, instead of directly using the entire aggregated data. We conducted experiments using real-world and synthetic trajectory data to validate our self-consistent calibration framework. [ABSTRACT FROM AUTHOR]

To quickly optimize the cooling performance of three-dimensional coolant channels in a proton exchange membrane fuel (PEMFC) cell, a generative adversarial network (GAN) model that adopts small-scale sample data to predict the coolant channel topology structure is constructed. The coordinate information of the topological pseudo-density field is directionally input into the neural network to improve prediction accuracy. The results show that more microtopologies in the coolant channels can be predicted with the GAN model than with traditional thermal–fluid–structural topology optimization. The topological configuration with a maximum temperature of 0.15 K, lower than the training dataset, is achieved. The well-trained GAN model can generate topological structures for the optimization objective, that is, thermal performance superior to the training set. The proposed model can also generate topological structures with better fluid and structural performance, which is 20.44% and 9.25% superior to that of the training dataset, respectively. The computation time required by the GAN model is <1 s, while the computation time for the same case is 30.2 h using the traditional thermal–fluid–structural topology optimization. These findings can aid in designing coolant channels in PEMFCs. • Deep-learning accelerating topology optimization of 3D coolant channel is proposed. • Micro-topologies in coolant channels is well predicted with GAN model. • Topologies with better fluid and structural performance are obtained using GAN model. • Computation time is obviously reduced compared to traditional topology optimization. [ABSTRACT FROM AUTHOR]

Based on the BP neural network model of machine learning method, the corresponding random input parameters are generated by Monte Carlo method, and the prediction of TBM driving speed is studied. In this study, the machine learning method is applied to the prediction of TBM penetration rate, and the established empirical model has higher accuracy and practicability. After selecting the predictive control type of BP neural network, according to the control requirements of TBM, system composition and the characteristics of different geological tunneling, the appropriate data are selected to train the neural network, and the predictive control model of neural network for TBM with high convergence and real-time performance is established. Monte Carlo method has strong optimization and control functions in the realistic planning of many complex problems. In the process of TBM velocity prediction, the random input of parameters is realized by Monte Carlo method, which makes the prediction more accurate. BP neural network is used to predict the penetration rate of TBM. Its accuracy mainly depends on the accuracy of input parameters. The actual measured and predicted values of TBM driving speed are basically near the straight line x = y as the horizontal and vertical coordinates, and the correlation coefficient R = 0.9789. Therefore, the BP neural network combined with genetic algorithm has a high reference value for the prediction of TBM driving speed. When the TBM type is the same and the system equipment is the same, four factors, namely uniaxial compressive strength, Brazilian tensile strength, peak slope index, and distance between planes of weakness, are taken as input parameters of BP network by calculating the weight of influencing factors. In the specific operation, the genetic algorithm is used to iterate continuously to find the optimal solution of the initial weight parameters of BP neural network. In this study, this prediction method is applied to practical prediction. The feasibility of this method is verified by comparing with the final actual measurement result, which is of great practical significance to the evaluation of engineering, design scheme and cost control. [ABSTRACT FROM AUTHOR]

Photoreduction of CO2 into solar fuels is usually regarded as one of the promising solutions to overcome environmental pollution and the energy crisis. The main challenge in CO2 photoreduction (CO2PR) is the low efficiency and poor selectivity. Layered double hydroxides (LDHs) are a class of 2D materials, consisting with M(OH)6 octahedra in the host layers and intercalated anions. Owing to the tuneable composition, particle size, morphology, and virtue coordinatively unsaturated active sites, a series of efficient strategies (morphology control, heterostructure, defect control, etc.) in LDH‐based photocatalysts have been efficiently developed to enhance the photocatalytic selectivity and activity for CO2PR. This review summarizes recent progress on the LDH‐based photocatalysts for CO2PR. [ABSTRACT FROM AUTHOR]

• We propose a concept of stochastic linguistic term (SLT). • SLT with complete probability distribution used for linguistic assessments with the aid of stochastic analysis. • Attribute aspirations are considered based on prospect theory. • An approach to ranking alternatives in SLT analysis is presented. • A numeric example and comparative analysis are conducted. Linguistic distribution assessments with probabilistic information are a flexible means to express the opinions of decision makers (DMs) with importance degree of each linguistic term. Therefore, research on multi-attribute group decision making (MAGDM) problems with linguistic distribution assessments is increasing. However, the probability distribution is usually only partially known. In order to obtain the complete probability distribution information, we propose the concept of stochastic linguistic term (SLT) with the aid of stochastic analysis. The SLT is an extension of general linguistic terms. Linguistic assessments with different models can be expressed as SLTs with complete probability distributions. Then the weighted averaging operator and score function of SLTs are presented. Considering the psychological behavior of DMs in decision making, we combine prospect theory and SLTs to handle uncertainty in MAGDM problems. Considering 2-tuple aspirations on attributes, a new MAGDM method with stochastic uncertainty based on prospect theory under linguistic assessments is proposed. Finally, a numeric example and comparative analysis illustrate the effectiveness and feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

In recent years, great attention has been paid to cascade reactions, which can improve efficiency and reduce waste production by implementing several consecutive reactions. Herein, two bifunctional catalysts were successfully prepared by precise control of the oriented layered double hydroxides (LDHs) growth on graphene oxides (GO) using a single‐drop and co‐precipitation method, respectively. The resultant Ru/LDH‐GO‐P and Ru/LDH‐GO‐V composites were characterized by EXAFS, FT‐IR, XRD, TG‐DTA, BET, XPS, TEM, CO2‐TPD, O2‐TPD, etc. The catalytic performance of Ru/LDH‐GO‐P and Ru/LDH‐GO‐V for one‐pot oxidation‐Knoevenagel condensation reaction showed significant difference under the same experimental conditions, in which the Ru/LDH‐GO‐P showed 99 % conversion and 99 % selectivity, in marked contrast of 60.7 % conversion and 47.9 % selectivity using Ru/LDH‐GO‐V as catalyst. The large enhancement of the catalytic performance using Ru/LDH‐GO‐P can be attributed to the following reasons: 1) the Co3+ centers in Ru/LDH‐GO‐P can promote the formation of surface oxygen vacancies that can adsorb and activate O2 to get better performance; 2) the Ru/LDH‐GO‐P exhibited larger BET surface and more medium‐strong basic active sites than the Ru/LDH‐GO‐V. Moreover, the Ru/LDH‐GO‐P catalyst can be easily recovered from the reaction system and reused for at least five times without obvious deterioration of its catalytic activity or structural integrity. [ABSTRACT FROM AUTHOR]

• A simple spatial phase modulation laser interferometer (SPMLI) is presented. • The reflected beams from the upper and lower surfaces of the transparent plate produce two-beam interference. • The spatial frequency of the image is proportional to the wave number of the laser light and the thickness of the transparent plate. • The proposed interferometer can be used for wavelength and thickness measurements. • The proposed interferometer has the advantages of simple structure, low cost and no need for mechanical scanning components. We propose and realize a spatial phase modulation laser interferometer (SPMLI), which mainly consists of a laser source, an optical fiber, a transparent plate and a linear charge coupled device (CCD). The reflected beams from the upper and lower surfaces of the transparent plate produce two-beam interference. The generated spatial phase modulation interference image is taken by the CCD. The spatial frequency of the image is proportional to the wave number of the laser light and the thickness of the transparent plate. Experimental results show that the wavelength and thickness can be measured in picometer-level and nanometer-level resolution, respectively. Compared with other interferometers, the proposed interferometer has the advantages of simple structure, low cost and no need for mechanical scanning components. [ABSTRACT FROM AUTHOR]

Revealing the mechanisms underlying soil microbial community assembly is a fundamental objective in molecular ecology. However, despite increasing body of research on overall microbial community assembly mechanisms, our understanding of subcommunity assembly mechanisms for different prokaryotic and fungal taxa remains limited. Here, soils were collected from more than 100 sites across southwestern China. Based on amplicon high‐throughput sequencing and iCAMP analysis, we determined the subcommunity assembly mechanisms for various microbial taxa. The results showed that dispersal limitation and homogenous selection were the primary drivers of soil microbial community assembly in this region. However, the subcommunity assembly mechanisms of different soil microbial taxa were highly variable. For instance, the contribution of homogenous selection to Crenarchaeota subcommunity assembly was 70%, but it was only around 10% for the subcommunity assembly of Actinomycetes, Gemmatimonadetes and Planctomycetes. The assembly of subcommunities including microbial taxa with higher occurrence frequencies, average relative abundance and network degrees, as well as wider niches tended to be more influenced by homogenizing dispersal and drift, but less affected by heterogeneous selection and dispersal limitation. The subcommunity assembly mechanisms also varied substantially among different functional guilds. Notably, the subcommunity assembly of diazotrophs, nitrifiers, saprotrophs and some pathogens were predominantly controlled by homogenous selection, while that of denitrifiers and fungal pathogens were mainly affected by stochastic processes such as drift. These findings provide novel insights into understanding soil microbial diversity maintenance mechanisms, and the analysis pipeline holds significant value for future research. [ABSTRACT FROM AUTHOR]

As a biomass‐derived platform molecule, 5‐hydroxymethylfurfural (5‐HMF) is a highly desirable feedstock for manufacturing of high value‐added chemicals ranging from starting materials for polyesters to biofuels. In this work, we reported the fabrication of a series of multicomponent solid acid catalysts based on heteropolyacids immobilized ILs‐modified organosilica hollow nanospheres (denoted as PW12‐ILs‐Cn‐HNS), in which PW12 (PW12=H3PW12O40 ⋅ xH2O) provides Brønsted acid site, ILs show strong electrostatic interactions with PW12, Cn (Cn=alkyl chain) is attached for hydrophobicity and HNS represents organosilica hollow nanospheres. When applied for catalytic dehydration of fructose to 5‐HMF, the PW12‐ILs‐C4‐HNS catalyst with 15.2 % PW12 loading exhibited the best dehydration activity to 5‐HMF with 93.7 % yield in DMSO at 100 °C in 2 h. Compared with 2D hexagonal and 3D interconnected structures, the excellent porosity properties of hollow nanospherical structure can provide a high population of the PW12 sites and enough confined nanospace for the dehydration of fructose. Moreover, the PW12‐ILs‐Cn‐HNS catalyst showed excellent stability over six catalytic cycles without obvious loss of activity. Most importantly, careful identification of the observed intermediates revealed crucial information for the dehydration process of fructose to 5‐HMF. As such, the proposed heterogeneous catalysts show great potential in biomass conversion processes. [ABSTRACT FROM AUTHOR]

Abstracts This study aimed to improve the solubility, reduce the side effects and enhance the efficacy of gambogic acid against acute myeloid leukemia in vitro and in vivo. This oil-in-water nanoemulsion (average size 17.20 ± 0.11 nm, zeta potential 4.17 ± 0.82 mV) containing Tween-80, glycol, squalene and gambogic acid with improving 4000 times solubility was prepared by pseudoternary phase diagrams. We found that this nanoemulsion successfully encapsulated gambogic acid; it was stable and showed an obvious delayed release effect for the drug in three different phosphate-buffered saline (pH = 2.0, 5.8 and 7.4). The half inhibiting concentration (IC 50) of this nanoemulsion (480.7 μg/mL and 408 μg/mL) were 1.67 times and 1.98 times higher than those of its water solution (287 μg/mL and 206 μg/mL) after acting on the toxicity standard cell line (L929 line) for 24 h and 48 h, respectively. Importantly, acute injection toxicity indicated that the half lethal dose (LD 50) of this nanoemulsion (23.25 mg/kg, 95% LD 50 , 21.7–25.16 mg/kg) was 1.26 times higher than that of its water solution (18.59 mg/kg, 95% LD 50 , 16.84–20.53 mg/kg). Compared with its suspension, the bioavailability of this nanoemulsion was 318.2%. Furthermore, this nanoemulsion had a better efficacy against the acute myeloid leukemia in vitro and in vivo by improving the time and percent of survival (MV4-11 engrafts mice) and reducing half inhibiting concentration values in acute myeloid leukemia such as Jurket, HL-60 and MV4-11 cells. Our studies suggested that this nanoemulsion may be a promising therapeutic medicine for acute myeloid leukemia. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the multi-attribute group decision making (MAGDM) problems with respect to psychological behavior of regret aversion of decision makers (DMs), in which the attribute values are expressed in multi-granular linguistic terms and numerical values. This study proposes a general model based on two-tuple linguistics to deal with multi-granular linguistic information in order to manage information provided by different experts. A practical transformation approach is developed, which makes numerical values expressed in two-tuple linguistics and further converted into values in [0, 1] interval. Compared with the traditional MAGDM model, a tri-level decision making model that includes a top DM, multiple middle level DMs and multiple experts is considered. A novel mathematical programming model is constructed considering all middle level DMs’ preference information and regret aversion. Finally, an illustrative example is given to verify the proposed method. The results and comparative analysis demonstrate its effectiveness and practicability. [ABSTRACT FROM AUTHOR]

To improve the cooling performance of coolant channels in a proton exchange membrane fuel cell (PEMFC), three-dimensional thermal-fluid-structural topology optimization method is proposed. The maximum temperature of the bipolar plates is treated as the objective function. The volume fraction, power dissipation and structural displacement are considered as constraints. The influences of constraints and inlet velocities on the topology optimization performance are investigated. Results show that the initial topology optimal multichannel achieves a 1.92 K maximum temperature reduction and 15.22% cooling performance improvement compared to the traditional straight multichannel. The temperature decreases by 0.5 K and the cooling performance improves by 3.82% and 3.48% when the power dissipation and structural displacement constraints are relaxed by 1.34 and 1.25 times higher than the initial topology optimal configuration, respectively. The maximum temperatures in topology optimal configuration decrease from 354.43 K to 352.76 K and from 339.52 K to 337.19 K when the inlet velocity ranges from 0.05 m/s to 0.3 m/s compared with that of the traditional straight multichannel for uniform and parabolic inlet velocities, of which the cooling performance improves by 7.87–36.59% and 8.12–31.14%, respectively. The above findings have application prospects on designing the coolant channels of PEMFCs. • Nonuniform heat flow conducted to bipolar plates in PEMFCs is considered. • 3D topology optimization method is proposed in PEMFC coolant channel optimization. • Power dissipation and structural stiffness constraints are used in optimization. • Influence of the constraints on topology optimization results is discussed. • Influence of inlet velocity distribution on optimization performance is discussed. [ABSTRACT FROM AUTHOR]

Stress, including both psychological and physical stimulation, can cause changes in the microbiota and mucosal function of the gastrointestinal system. There are few research studies available about the faecal microbiota changes after stress, such as water immersion restraint stress (WIRS). Therefore, in this study, we focused on analysing the composition changes of faecal microbiota in WIRS mice. The WIRS model, in which Blab/c mice were immersed in 21 ± 2 °C water for 4 h each day for 14 days, was established. Behavioural changes, the serum levels of corticosterone, IFN-γ and IL-17 and gastric mucosal injury were also assessed. Ten faecal microbiota samples were detected by Illumina Miseq sequencing of the 16S rRNA genes from 367205 characterised sequences. Finally, we find significant differences in the faecal microbiota composition between the control and the WIRS groups. There was an obvious increase in Lachnospiraceae in the WIRS mice (p = 0.0286, p < 0.05), which is associated with human diseases, such as ulcerative colitis, Crohn's and celiac disease. Our research indicates that stress changes in the faecal microbiota. These results suggest that observing shifts of the intestinal microbiota is a promising method to explore the mechanism of the stress associated with gastrointestinal diseases and to provide us with a better understanding of the relationship between the microbiota and disease. [ABSTRACT FROM AUTHOR]

Intercalation catalysts, owing to their modular and accessible gallery and unique interlamellar chemical environment, have shown wide application in various catalytic reactions. However, the poor mass transfer between the active components of the intercalated catalysts and organic substrates is one of the challenges that limit their further application. Herein, we have developed a novel heterogeneous catalyst by intercalating the polyoxometalate (POM) of Na9LaW10O36⋅32 H2O (LaW10) into layered double hydroxides (LDHs), which have been covalently modified with ionic liquids (ILs). The intercalation catalyst demonstrates high activity and selectivity for the epoxidation of various allylic alcohols in the presence of H2O2. For example, trans-2-hexen-1-ol undergoes up to 96 % conversion and 99 % epoxide selectivity at 25 °C in 2.5 h. To the best of our knowledge, the Mg3Al−ILs−C8−LaW10 composite material constitutes one of the most efficient heterogeneous catalysts for the epoxidation of allylic alcohols (including the hydrophobic allylic alcohols with long alkyl chains) reported so far. [ABSTRACT FROM AUTHOR]

The urbanization of China is changing from incremental growth to urban intensification, and urban compactness is a significant attribute for measuring the intensified degree of regional space and societal frameworks. We carefully outline the inadequacies of compactness measuring methodologies and associated research, and argue that compact cities and metro systems contribute to urban sustainable development in tandem. Thereby, this paper investigated 27 strategic region of metro stations on Chengdu Metro Line 1 and proposed a novel urban compactness model in three-dimensions. The result demonstrates that the old urban area before the development of the metro system and the new town thereafter have extreme compactness outcomes, resulting in significant contrasts in morphology and intensification indices. This study investigates the correlation and interaction processes among compactness, morphology, and intensive multiple variables in order to give theoretical and practical support for the intensification design of these two regions in Chengdu. [ABSTRACT FROM AUTHOR]

Natural surfactant mediated microwave-assisted extraction (NSM-MAE) technique was developed and performed for the simultaneous extraction of hydrophilic and hydrophobic phytochemicals from plant matrix, such as phenolic acid, coumarin, bisepoxy lignan and phenylpropanoid from Acanthopanax senticosus stems. The natural surfactant soapnut saponin (SS) ethanol solution was chosen as the best solvent for the efficient extraction of active constituents from plant matrix after screening ten different types of the surfactants. The relevant key experiment parameters during the extraction process were optimized by Box-Behnken design (BBD) and single factor test. Extraction process with the optimized relevant parameters: liquid solid ratio 43 mL/g, 0.8% (g/mL) SS, extraction time 15 min, microwave power 470 W, and system temperature 60 ℃, extraction yields of the eleutheroside E, protocatechuic acid, isofraxidin, chlorogenic acid and eleutheroside B finally reached 1658.38, 312.71, 631.62, 16,282.17 and 3215.39 μg/g, respectively. The extraction yields was 1.34 fold higher than that of conventional ethanol based ultrasound-assisted extraction (Et-UAE) method. Furthermore, ABTS and DPPH free radical scavenging ability were used to investigate effects of different extraction methods. Moreover, foam separation technique was used to enrich and recycle soapnut saponin from extraction solvents. The present study indicated that the integrated NSM-MAE method was a safe, green and effective technique for the extraction and enrichment of targeted active phytochemicals from plant matrix and this method could be considered as a novel promising extraction technique to be scaled up in the industry production. [Display omitted] • Green extraction technique (MAE) was used to extract multiple phytochemicals in Acanthopanax senticosus stems. • Natural surfactant solvents (soapnut saponin) provides a choice to replace conventional organic solvents. • Foam separation technique was utilize to recycle natural surfactant. • NSM-MAE exhibited excellent extraction yields and radical scavenging capacity. [ABSTRACT FROM AUTHOR]

Aiming at solving the heat dissipation problem in a hydrogen unmanned aerial vehicle (UAV), this work uses an open metal foam as the enhanced heat transfer device in the air-cooling channel. The method of improving comprehensive heat transfer capacity and weight reduction by controlling the micropore directions and sizes in the metal skeleton is proposed. The real open cell metal foam structures are scanned and restructured using the X-ray computed tomography imaging system and corresponding computer software. The effects of micropore directions and sizes in the skeleton on pressure drops, conjugate heat transfer, volumetric heat transfer coefficient, comprehensive heat transfer capacity as well as weight reduction are discussed with the inlet velocity ranging from 10 m/s to 80 m/s. Results find that the micropore direction parallel to flow owns a higher comprehensive heat transfer capacity compared with that vertical to flow. There are existing a competitive relationship between heat conduction and heat convection in the metal skeleton. When the micropore size is 0.01, a best enhanced heat dissipation performance can be achieved. The structure with micropore size of 0.03 has a 8.49% weight reduction and 4.72–5.91% improvement of comprehensive heat transfer performance compared with that of the structure without micropores. The above findings can be applied to design a light and high comprehensive heat transfer device in the hydrogen UAV. • Real open-cell metal foam structure is captured by X-ray CT imaging system. • Micropore in skeleton influences on heat and mass transfer in PEMFC are analyzed. • Competitive relationship between heat convection and conduction is identified. • Comprehensive heat transfer improvement and weight reduction is realized. [ABSTRACT FROM AUTHOR]

Context and aims: Melatonin is a powerful antioxidant regulating various biological functions, including alleviating male reproductive damage under pathological conditions. Here, we aim to analyse the effect of melatonin on normal male reproduction in mice. Methods: Male mice received an intraperitoneal injection of melatonin (10 mg/kg body weight) for 35 consecutive days. The testis and epididymis morphology, and epididymal sperm parameters were examined. PCNA, HSPA2, SYCP3, ZO-1 and CYP11A1 expressions in epididymis or testis were detected by immunohistochemistry or Western blotting. Male fertility was determined by in vivo and in vitro fertilisation (IVF) experiments. The differentially expressed sperm proteins were identified by proteomics. Key results: No visible structural changes and oxidative damage in the testis and epididymis, and no significant side effects on testis weight, testosterone levels, sperm motility, and sperm morphology were observed in the melatonin-treatment group compared with the control group. Spermatogenesis-related molecules of PCNA, SYCP3, ZO-1, and CYP11A1 showed no significant differences in melatonin-treated testis. However, PCNA and HSPA2 increased their expressions in the epididymal initial segments in the melatonin-treatment group. Normal sperm fertilisation, two-cell and blastocyst development were observed in the melatonin-treated group, but melatonin significantly enhanced the sperm binding ability characterised as more sperm binding to one oocyte (control 7.2 ± 1.3 versus melatonin 11.8 ± 1.5). Sperm proteomics demonstrated that melatonin treatment enhanced the biological process of cell adhesion in sperm. Conclusions and implications: This study suggests that melatonin can promote sperm maturation and sperm function, providing important information for further research on the physiological function and protective effect of melatonin in male reproduction. Melatonin has antioxidant properties and is a common health supplement. Melatonin usage in physiological state has no reproductive side effects and can promote the ability of sperm to combine with egg. Melatonin may improve sperm function and may be used in the treatment of poor quality sperm by enhancing the expression of sperm adhesion proteins. [ABSTRACT FROM AUTHOR]

[Display omitted] • Propose a deep learning-based method Transformers Enhanced Segmentation Network. • Adopt multi-stage architecture to provide high-quality target detection. • Introduce Transformer into the mask head to provide high-quality segmentation. • Proposed method is fully automated and provides humanoid particle size measurement. • Provide a solution for nanoparticle size measurement under complex situations. The size of nanoparticles has a great influence on the properties of nanomaterials. Transmission electron microscope (TEM) is the most reliable and intuitive way to observe the size of nanoparticles but is only suitable for separated particles under existing traditional algorithms and deep learning methods. Therefore, we proposed a Transformers Enhanced Segmentation Network (TESN) to accurately segment nanoparticles. Based on Mask R-CNN, TESN introduces the multi-stage architecture and adopts hybrid CNN-Transformers architecture as the mask head. TESN shows excellent performance in the segmentation even under complex situations such as multiple nanoparticles overlap or nanoparticle edge fuzzy, the AP 50:5:95 reaches 0.910 on the test set. We applied TESN to the size measurement of nanospheres and compared with other measurement methods. The results of TESN are closest to the manual annotation, the error of size measurement for the four gold nanospheres with different sizes ranges from 0.38% to 3.52%. [ABSTRACT FROM AUTHOR]

Heat transfer performance of metal foam relies greatly on fluids flow direction due to the presence of the complex micropores in the skeleton. In this work, to explore the effect of different direction micropores in skeleton on the flow and heat transfer, a pore-scale simulation is performed after the reconstruction of realistic three-dimensional metal foam structures. The heat transfer performances of the metal foam with micropores in X- and Y- directions are calculated and compared with the structure without micropores. Results show that the pressure drops of the structure owning X-direction micropores are 4.52%–6.47% lower than those in the structure without micropores, while the pressure drops of the structure owning Y-direction micropores are 0.54%–0.88% higher. The heat transfer coefficients of the structure owning X-direction micropores are 1.39%–3.29% higher than those of the structure without micropores, while the structure owning Y-direction micropores are 0%–1.94% higher. The comprehensive heat transfer factors of the structure owning X-direction micropores are 2.96%–5.62% higher than those of the structure without micropores. The above findings can help design a high comprehensive heat transfer performance of metal foam using the different direction micropores in skeleton structure. • Different direction micropores metal foam is reconstructed. • Flow and heat transfer in metal foam considering micropores is studied. • Micropores in skeleton structure enhances heat transfer. • Comprehensive heat transfer for structure with X-direction micropores is higher. [ABSTRACT FROM AUTHOR]

• Developed an integrated microscopic simulation model for mixed autonomy traffic. • Characterized network traffic instability due to turning and merging maneuvers. • Effects of adaptive signal control and adaptive driver routing are compared with cooperative merging. • Analyzed the NFDs with different vehicle compositions and penetration rates. Connected and/or automated vehicles (CAVs or AVs) have been shown to dampen stop-and-go waves in mixed autonomy traffic, thus improving string stability. However, their effects on network traffic instability due to turning and merging maneuvers are less known. In this paper, we characterize such effects using the macroscopic or network fundamental diagram (MFD or NFD). We first revisit and extend the theoretical two-ring network, and then develop an integrated modeling and simulation framework that explicitly accounts for different microscopic traffic models of human-driven vehicles (HVs), AVs, and CAVs. Results suggest that network traffic instability resulting from turning and merging maneuvers persists even if vehicles become automated and cooperative. When the turning probability is low, the presence of CAVs does not induce a significant change in the bifurcation point of the NFD. Scatter in both link fundamental diagrams (FDs) and NFDs, however, reduces resulting in higher and more stable network flows. When the turning probability is high, AVs without cooperation turn out to worsen network traffic stability, giving rise to an NFD that undergoes bifurcation long before the theoretical critical network density is reached. This is in contrast to the case with CAVs that perform cooperative merging. Results also suggest that, whenever the penetration rate of CAVs is too low or too high, making HVs connected is not as effective in delaying the bifurcation of the NFD as when the penetration rate is moderate. We further compare cooperative merging with adaptive signal control and adaptive driver routing to demonstrate its benefits in improving network flows. Simulation experiments on a real motorway segment in Sydney, Australia are also performed to confirm our findings. [ABSTRACT FROM AUTHOR]

GaN high-electron-mobility transistor (HEMT) terahertz (THz) detectors have been widely studied and applied in the past few decades. However, there are few reports about the influence of GaN/AlGaN heterostructure material properties on the detection model at present. In this paper, a response voltage model for a GaN HEMT THz detector that considers the carrier scattering in a GaN/AlGaN heterostructure is proposed. The phonon scattering, dislocation scattering, and interface roughness scattering mechanisms are taken into account in the classic THz response voltage model; furthermore, the influence of various material parameters on the response voltage is studied. In a low-temperature region, acoustic scattering plays an important role, and the response voltage drops with an increase in temperature. In a high temperature range, optical phonon scattering is the main scattering mechanism, and the detector operates in a non-resonant detection mode. With an increase in carrier surface density, the response voltage decreases and then increases due to piezoelectric scattering and optical phonon scattering. For dislocation and interface roughness scattering, the response voltage is inversely proportional to the dislocation density and root mean square roughness (RMS) but is positively related to lateral correlation length. Finally, a comparison between our model and the reported models shows that our proposed model is more accurate. [ABSTRACT FROM AUTHOR]

• A calculation method for the estimating RC columns, beams, and walls yield deformation is proposed. • The method explicitly considers the effect of shear deformation and bar slippage in addition to flexural deformation. • A large database of past results of experiments done in Japan have been used to verify its accuracy. • Some factors which could influence the accuracy of proposed method are discussed. This paper focuses on the development and verification of a unified calculation method for estimating the yield of reinforced concrete (RC) beams, columns, and walls deformation considering flexural deformations, shear deformations, and bar slip deformations. Each component of yield deformation is considered independently, and the estimated yield deformation is the sum of these three parts. To verify the accuracy of this method, yield deformation results from a database of experimental results from tests performed in Japan on RC components was compared against those predicted by the proposed methods. The results show that the proposed method provides a reasonable prediction of the yield deformation and show that the proposed method has a better estimate of yield deformation than other previous methods. Sensitivity analysis on the influence of the rigidity reduction rate due to the shear effect, and the anchorage length in the bar slippage calculation, was performed. It was found that the rigidity reduction rate factor could influence the accuracy for walls. The influence of other material and member characteristics are also discussed herein. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy (SEM) plays a crucial role in the characterization of nanoparticles. Unfortunately, due to the limited resolution, existing imaging techniques are insufficient to display all detailed characteristics at the nanoscale. Hardware-oriented techniques are troubled with costs and material properties. Computational approaches often prefer blurry results or produce a less meaningful high-frequency noise. Therefore, we present a staged loss-driven neural networks model architecture to transform low-resolution SEM images into super-resolved ones. Our approach consists of two stages: first, residual channel attention network (RCAN) with mean absolute error (MAE) loss was used to get a better peak signal-to-noise ratio (PSNR). Then, discriminators with adversarial losses were activated to reconstruct high-frequency texture features. The quantitative and qualitative evaluation results indicate that compared with other advanced approaches, our model achieves satisfactory results. The experiment in AgCl@Ag for photocatalytic degradation confirms that our proposed method can bring realistic high-frequency structural detailed information rather than meaningless noise. With this approach, high-resolution SEM images can be acquired immediately without sample damage. Moreover, it provides an enhanced characterization method for further directing the preparation of nanoparticles. [ABSTRACT FROM AUTHOR]

• Moisture damage was induced in the PAM via freeze–thaw (F-T) cycling. • The PAM strength decreased with F-T cycle following an exponential decay function. • At higher stresses the PAM exhibited higher fatigue dependence on moisture damage. • Predictive models were developed for the single- and two-stage IDT fatigue loading. • Miner's sum M < 1 for the H-L sequence and M > 1 for the L-H sequence. This study investigated the fatigue behavior of a porous asphalt mixture (PAM) considering the effect of moisture damage. The PAM was designed with a high-viscosity asphalt and target air void of 20%. Moisture damage was induced through freeze–thaw (F-T) conditioning with 1, 3, 5, 10, and 15 cycles, and was quantified in terms of loss in the indirect tensile (IDT) strength. The IDT fatigue test with the single- and two-stage loading patterns was employed. Results indicated that the strength decreased with the number of F-T cycles following an exponential decay function. Moisture damage rendered the PAM more susceptible to fatigue loading, and at higher stress levels the material exhibited higher fatigue dependence on moisture damage. In the S-N relationships established from the single-stage fatigue characterization, the role of moisture damage was incorporated into the intercept and slope as exponential functions. The two-stage characterization resulted in the Miner's sum M < 1 for the high-to-low loading sequence, and M > 1 for the low-to-high sequence. The power-law nonlinear damage rule was adopted, in which the dependence of the exponent on moisture damage was found to follow an exponential decay function. In the predictive models developed for both loading patterns, the effects of moisture damage and loading level were mathematically described in uncoupled forms, as a result of no moisture damage progression during fatigue loading. [ABSTRACT FROM AUTHOR]

Designing an accurate and efficient heat protection system for the area around the high-temperature stagnation point on supersonic aircraft is still an important topic of research. In the present study, a three-dimensional high thermal conductivity carbon/carbon (C/C) composite thermal protection system embedded with L-shaped carbon fiber bundles for directional heat transfer is proposed as a high-efficiency thermal protection design. A multi-scale method, which couples the finite volume method (FVM) and lattice Boltzmann method (LBM), is developed to investigate the directional heat transfer in the proposed structure. The FVM is used to calculate the heat radiation information, which is needed to solve the energy equation with the LBM. Further, the failure temperature of the proposed thermal protection structure is defined. The effects of the porosity, carbon fiber bundle and pore diameter on the directional heat transfer of the L-shaped C/C composite thermal protection system are investigated in detail. The results show that the effective thermal conductivity of the proposed thermal protection system increases with increasing temperature and carbon fiber bundle diameter. It decreases with increasing porosity when the temperature is below 1000 °C. There exists the competitive relationship between the pore heat radiation and carbon fiber bundle thermal conductivity. An increased porosity results in a decrease in the failure temperature of the proposed thermal protection structure, while increasing the carbon fiber bundle diameter can increase the failure temperature. These findings can provide some new insights for designing a high-performance C/C composite thermal protection system. • 3D C/C L-fiber directional heat transfer thermal protection system is proposed. • LBM coupled FVM method considering the radiant heat transfer is adopted. • Failure temperature for directional heat transfer system is obtained. • Relationships between heat flux of radiation and heat conduction is studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photoreduction CO 2 to syngas evolution could be achieved by CoMgAl-LDH. • The highl high dispersion of Co and hydroxyl defects contributed the photoactivity. • CoMgAl-LDH exhibited excellent performance under high wavelength of 650 nm. The conversion of solar energy to chemical fuels by CO 2 photoreduction reaction (CO 2 PR) is a promising pathway to alleviate rapid energy consumption crisis. Nevertheless, only a few systems have been reported so far by applying solar energy in visible light region in particular high wavelength (such as λ ≥ 650 nm). Herein, we report an efficient 650 nm-induced CO 2 photocatalytic reduction system to syngas by introducing Co into MgAl-layered double hydroxide (CoMgAl-LDH) nanosheets in conjunction with Ru(bpy) 3 ]Cl 2 ·6H 2 O as photosensitizer, in which [Ru(bpy) 3 ]Cl 2 ·6H 2 O could be activated to generate photogenerated electrons which further transfer to surface of CoMgAl-LDH for CO 2 reduction. Under irradiation >400 nm, the CoMgAl-LDH nanosheets showed excellent CO 2 conversion with TOF of 11.57 h−1, 3 times higher than that of CoAl-LDH. Most importantly, up to monochromatic irradiation wavelength at 650 nm, the CoMgAl-LDH nanosheets still displayed optimized syngas evolution rate, with CO rate of 0.35 μmol·h−1 with quantum yield of 0.86%. Furthermore, as evidenced by X-ray absorption fine structure spectroscopy and high-resolution synchrotron X-ray powder diffraction, the proper introduction of Co promoted its dispersion on the laminate of LDH. The suitable dispersion of Co active sites into LDH nanosheets facilitates the transportation of photo-generated electrons to further promote catalytic activity for reaction. This work paves a potential way for CO 2 PR to syngas under wavelength irradiation up to 650 nm. [ABSTRACT FROM AUTHOR]

Clarifying the relationship between crystal evolution and the physical foaming behavior of high-hardness thermoplastic polyurethane (HD-TPU) is essential for preparing HD-TPU foams with controllable cellular morphology. In this study, two thermal treatment methods, isothermal annealing and isothermal crystallization, were utilized to control the crystal structure of HD-TPU. The effect of crystals on the physical foaming behavior of HD-TPU foams was examined. The annealing process produced mainly lamellae and Form Ⅰ structure, while isothermal crystallization primarily led to Form Ⅱ spherulites. Foams based on original and pre-treated HD-TPU were prepared by pressure quench foaming. The evolution of foam density and cell morphology was discussed. At low foaming temperatures, crystals induced the heterogeneous nucleation. Realizing a uniform cell structure at high foaming temperatures could be challenging when the spherulite size was large. When the size of the spherulite was small but loosely distributed, larger cells with thinner cell walls could be obtained. However, if the spherulite distribution was dense, the spherulites hindered cell growth, resulting in unevenly distributed and deformed cells. [Display omitted] • HD-TPU samples with crystal structures from lamellae, to Form Ⅰ paracrystals and Form Ⅱ spherulites were generated. • HD-TPU foams with densities of about 0.45–1.1 g/cm3 were fabricated using CO 2 as a foaming agent. • HD-TPU samples with nanoscale crystals developed by the annealing process acted as heterogeneous nucleating sites to enhance the cell nucleation. • Form II spherulites in HD-TPU could be induced by the melt-crystallization process; large spherulites hindered the cell growth. [ABSTRACT FROM AUTHOR]

• We successfully synthesized a series of NiO with different amounts of Ni vacancy and O vacancy (V Ni&O) by using the topological transformation of the NiAl-LDH, which acts as the effective catalysts for the photoreduction CO 2 reaction. • The selectivity of CO 2 reduction under visible light irradiation could be tuned according to the vacancy concentration. The NiAl-275 (NiAl-LDH was calcinated in the air at 275 °C) possesses the highest content of defect demonstrated the highest CH 4 selectivity of 22.8%. With calcination temperature increase from 275 to 800 °C, the vacancy concentration decreases and the selective of CH 4 decreases to 0.4%. • Photocatalysts that can work under longer wavelengths. Moreover, with irritation wavelength λ > 600 nm, the H 2 evolution reaction can completely suppress and the selectivity of CH 4 can be further improved to 38.5%. • The DFT + U calculations revealed that under the irradiation wavelength above 600 nm, the photogenerated electrons located on the defect state of NiO (V Ni&O) possessed a driving force (0.519 eV) that could only overcome the Gibbs free energy barrier of CO 2 reduction to CH 4 and CO, rather than that for H 2 evolution (0.605 eV). Conversion of CO 2 into useful fuels and chemicals through solar energy offers opportunities to address the crisis of energy for fossil fuels and reduce climate-changing CO 2 emissions. In order to make use of solar energy efficiently, fabrication of photocatalysts that can work under longer wavelengths (such as λ > 600 nm), remains to attract intense attention. Herein, the NiO nanosheets containing an abundant of Ni&O vacancies were fabricated. Through fine-tuning the density of vacancies, we are able to control the selectivity of CH 4 , CO, and H 2 of the photoreduction CO 2 reaction. Furthermore, under irradiation with λ > 600 nm, the H 2 evolution reaction can be completely suppressed. The DFT+U calculations revealed that under the irradiation wavelength above 600 nm, the photogenerated electrons located on the defect state of NiO could only overcome the Gibbs free energy barrier of CO 2 reduction to CH 4 and CO, rather than that for H 2 evolution. [ABSTRACT FROM AUTHOR]

The number of patents increases quickly, while more and more low-quality patents are emerging. It's important to identify high-quality patents from massive data quickly and accurately for organizational R&D decision-making and patent layout. However, due to low percentage of high-quality patents, it is challenging to identify them efficiently. In order to solve above problem, we reconstruct the existing index system for identifying high-quality patents by adding 4 features from technological strength of patentees. Furthermore, we propose an improved model by integrating resampling technique and ensemble learning algorithm. First, generative adversarial networks (GAN) are used to expand minority samples. Second, Extreme Gradient Boosting algorithm (XGBoost) with Bayesian optimization (BO) is used to identify high-quality patents. For clarity, this model is called a GAN-BO-XGBoost model. To test the effectiveness of above model, we use patent data in field of lithography technology. Tenfold cross-validation is carried out to evaluate the performance between our proposed model and other models. The results show that GAN-BO-XGBoost model performs better and it's more stable than other models. [ABSTRACT FROM AUTHOR]

The tailoring of active sites is closely related to the substrate. Dual‐atom catalysts (DACs) have been achieved on doped carbon, oxides, and 2D materials, but are rarely reported on metals, due to the challenges of sintering and alloying using metal as the host. Herein, an innovative approach to anchor isolated single atoms as dual‐atomic‐site alloy (DASA) through two‐step pyrolysis of porous structure is proposed. Firstly, the role of Zn and Co in generating pores during the pyrolysis of zeolite imidazolate framework (ZIFs) is revealed, and a hierarchical porous structure with self‐supported Co particles is achieved by the first‐step pyrolysis. Diffusion‐controlled reduction of precursors containing target metals is then allowed through hierarchical structures by second‐step pyrolysis, so to address the challenge of sintering and alloying at pyrolysis of high temperatures. The approach is demonstrated by synthesizing Ir1Ni1@Co/N‐C DASA, with outstanding bifunctional oxygen reduction/evolution reaction (ORR/OER) performance in both acidic and alkaline media, which is rarely reported. The density functional theory (DFT) calculations represent that adsorption‐free energies of intermediates OH and O are regulated to nearly 0 eV by Ir1 and Ni1 on Co. This work demonstrates a new path of constructing DASA using the designed porous structure, inspiring catalysts design in a related field. [ABSTRACT FROM AUTHOR]

Catalytically active metals atomically dispersed on supports presents the ultimate atom utilization efficiency and cost‐effective pathway for electrocatalyst design. Optimizing the coordination nature of metal atoms represents the advanced strategy for enhancing the catalytic activity and the selectivity of single‐atom catalysts (SACs). Here, we designed a transition‐metal based sulfide‐Ni3S2 with abundant exposed Ni vacancies created by the interaction between chloride ions and the functional groups on the surface of Ni3S2 for the anchoring of atomically dispersed Pt (PtSA‐Ni3S2). The theoretical calculation reveals that unique Pt‐Ni3S2 support interaction increases the d orbital electron occupation at the Fermi level and leads to a shift‐down of the d ‐band center, which energetically enhances H2O adsorption and provides the optimum H binding sites. Introducing Pt into Ni position in Ni3S2 system can efficiently enhance electronic field distribution and construct a metallic‐state feature on the Pt sites by the orbital hybridization between S‐3p and Pt‐5d for improved reaction kinetics. Finally, the fabricated PtSA‐Ni3S2 SAC is supported by Ag nanowires network to construct a seamless conductive three‐dimensional (3D) nanostructure (PtSA‐Ni3S2@Ag NWs), and the developed catalyst shows an extremely great mass activity of 7.6 A mg−1 with 27‐time higher than the commercial Pt/C HER catalyst. [ABSTRACT FROM AUTHOR]

Relapses frequently occur following CD19-directed chimeric antigen receptor (CAR) T-cell treatment for relapsed or refractory B-cell acute lymphocytic leukaemia in children. We aimed to assess the activity and safety of sequential CD19-directed and CD22-directed CAR T-cell treatments. This single-centre, single-arm, phase 2 trial, done at Beijing GoBroad Boren Hospital, Beijing, China, included patients aged 1–18 years who had relapsed or refractory B-cell acute lymphocytic leukaemia with CD19 and CD22 positivity greater than 95% and an Eastern Cooperative Oncology Group performance status of 0–2. Patients were initially infused with CD19-directed CAR T cells intravenously, followed by CD22-directed CAR T-cell infusion after minimal residual disease-negative complete remission (or complete remission with incomplete haematological recovery) was reached and all adverse events (except haematological adverse events) were grade 2 or better. The target dose for each infusion was 0·5 × 106 to 5·0 × 106 cells per kg. The primary endpoint was objective response rate at 3 months after the first infusion. Secondary endpoints were duration of remission, event-free survival, disease-free survival, overall survival, safety, pharmacokinetics, and B-cell quantification. The prespecified activity analysis included patients who received the target dose and the safety analysis included all treated patients. This study is registered with ClinicalTrials.gov , NCT04340154 , and enrolment has ended. Between May 28, 2020, and Aug 16, 2022, 81 participants were enrolled, of whom 31 (38%) were female and 50 (62%) were male. Median age was 8 years (IQR 6–10), all patients were Asian. All 81 patients received the first infusion and 79 (98%) patients received sequential infusions, CD19-directed CAR T cells at a median dose of 2·7 × 106 per kg (IQR 1·1 × 106 to 3·7 × 106) and CD22-directed CAR T cells at a median dose of 2·2 × 106 per kg (1·1 × 106 to 3·7 × 106), with a median interval of 39 days (37–41) between the two infusions. 62 (77%) patients received the target dose, including two patients who did not receive CD22 CAR T cells. At 3 months, 60 (97%, 95% CI 89–100) of the 62 patients who received the target dose had an objective response. Median follow-up was 17·7 months (IQR 11·4–20·9). 18-month event-free survival for patients who received the target dose was 79% (95% CI 66–91), duration of remission was 80% (68–92), and disease-free survival was 80% (68–92) with transplantation censoring; overall survival was 96% (91–100). Common adverse events of grade 3 or 4 between CD19-directed CAR T-cell infusion and 30 days after CD22-directed CAR T-cell infusion included cytopenias (64 [79%] of 81 patients), cytokine release syndrome (15 [19%]), neurotoxicity (four [5%]), and infections (five [6%]). Non-haematological adverse events of grade 3 or worse more than 30 days after CD22-directed CAR T-cell infusion occurred in six (8%) of 79 patients. No treatment-related deaths occurred. CAR T-cell expansion was observed in all patients, with a median peak at 9 days (IQR 7–14) after CD19-directed and 12 days (10–15) after CD22-directed CAR T-cell infusion. At data cutoff, 35 (45%) of 77 evaluable patients had CAR transgenes and 59 (77%) had B-cell aplasia. This sequential strategy induced deep and sustained responses with an acceptable toxicity profile, and thus potentially provides long-term benefits for children with this condition. The National Key Research & Development Program of China, the CAMS Innovation Fund for Medical Sciences (CIFMS), and the Non-Profit Central Research Institute Fund of Chinese Academy of Medical Sciences. For the Chinese translation of the abstract see Supplementary Materials section. [ABSTRACT FROM AUTHOR]

Although progress has been made to improve photocatalytic CO2 reduction under visible light (λ>400 nm), the development of photocatalysts that can work under a longer wavelength (λ>600 nm) remains a challenge. Now, a heterogeneous photocatalyst system consisting of a ruthenium complex and a monolayer nickel‐alumina layered double hydroxide (NiAl‐LDH), which act as light‐harvesting and catalytic units for selective photoreduction of CO2 and H2O into CH4 and CO under irradiation with λ>400 nm. By precisely tuning the irradiation wavelength, the selectivity of CH4 can be improved to 70.3 %, and the H2 evolution reaction can be completely suppressed under irradiation with λ>600 nm. The photogenerated electrons matching the energy levels of photosensitizer and m‐NiAl‐LDH only localized at the defect state, providing a driving force of 0.313 eV to overcome the Gibbs free energy barrier of CO2 reduction to CH4 (0.127 eV), rather than that for H2 evolution (0.425 eV). [ABSTRACT FROM AUTHOR]

Although progress has been made to improve photocatalytic CO2 reduction under visible light (λ>400 nm), the development of photocatalysts that can work under a longer wavelength (λ>600 nm) remains a challenge. Now, a heterogeneous photocatalyst system consisting of a ruthenium complex and a monolayer nickel‐alumina layered double hydroxide (NiAl‐LDH), which act as light‐harvesting and catalytic units for selective photoreduction of CO2 and H2O into CH4 and CO under irradiation with λ>400 nm. By precisely tuning the irradiation wavelength, the selectivity of CH4 can be improved to 70.3 %, and the H2 evolution reaction can be completely suppressed under irradiation with λ>600 nm. The photogenerated electrons matching the energy levels of photosensitizer and m‐NiAl‐LDH only localized at the defect state, providing a driving force of 0.313 eV to overcome the Gibbs free energy barrier of CO2 reduction to CH4 (0.127 eV), rather than that for H2 evolution (0.425 eV). [ABSTRACT FROM AUTHOR]