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This study investigated the effects of partially replacing expensive Mo with cheaper Nb on the microstructure and properties of high-strength low-alloy (HSLA) steel during reverse austenisation. The mechanical properties of the steel in the hot-rolled state were lower with a partial replacement of Mo by Nb. However, after pre-tempering and reheating and quenching, the strength increased greatly while the ductility and toughness did not decrease much. Thus, the negative effects of replacing Mo with Nb were mostly alleviated, and a good balance between strength, ductility and toughness was achieved. After heat treatment, the mass percentage of precipitates increased substantially, which helped to pin grain boundaries during austenisation. The percent of high-angle grain boundaries greatly increased while the average effective grain size decreased, which improved grain refinement. The results showed that combining a partial replacement of Mo by Nb with heat treatment allows the microstructure and mechanical properties of HSLA steel to be effectively controlled while improving the balance between cost and performance. These findings provide valuable insights into the preparation and design of steels with similar microstructures.

The triboelectric nanogenerator (TENG), as a novel energy harvesting technology, has garnered widespread attention. As a relatively young field in nanogenerator research, investigations into various aspects of the TENG are still ongoing. This review summarizes the development and dissemination of the fundamental principles of triboelectricity generation. It outlines the evolution of triboelectricity principles, ranging from the fabrication of the first TENG to the selection of triboelectric materials and the confirmation of the electron cloud overlapping model. Furthermore, recent advancements in TENG application scenarios are discussed from four perspectives, along with the research progress in performance optimization through three primary approaches, highlighting their respective strengths and limitations. Finally, the paper addresses the major challenges hindering the practical application and widespread adoption of TENGs, while also providing insights into future developments. With continued research on the TENG, it is expected that these challenges can be overcome, paving the way for its extensive utilization in various real-world scenarios.

To analyze the structural characteristics of a human hand, data collection gloves were worn for typical grasping tasks. The hand manipulation characteristics, finger end pressure, and finger joint bending angle were obtained via an experiment based on the Feix grasping spectrum. Twelve types of tendon rope transmission paths were designed under the N + 1 type tendon drive mode, and the motion performance of these 12 types of paths applied to tendon-driven fingers was evaluated based on the evaluation metric. The experiment shows that the designed tendon path (d) has a good control effect on the fluctuations of tendon tension (within 0.25 N), the tendon path (e) has the best control effect on the joint angle of the tendon-driven finger, and the tendon path (l) has the best effect on reducing the friction between the tendon and the pulley. The obtained tendon-driven finger motion performance model based on 12 types of tendon paths is a good reference value for subsequent tendon-driven finger structure design and control strategies.

Rice production is the agricultural activity with the highest energy consumption and carbon emission intensity. Water and fertilizer management constitutes an important part of energy input for rice production and a key factor affecting greenhouse gas emissions from paddy fields. Water–fertilizer integration management (AIM) is an automated water and fertilizer management system for large-scale rice production, which can effectively save water and fertilizer resources. At present, the energy utilization and environmental impact of AIM in rice production are not clear. To clarify whether AIM is a water and fertilizer management measure that combines energy conservation and carbon emission reduction, a comparative study between the widely used farmers’ enhanced water and fertilizer management (FEM) in China and AIM was conducted in this paper. Field experiments were conducted to evaluate the rice yield, carbon emission, energy utilization, and economic benefits of the two management methods. The results showed that AIM reduced water and fertilizer inputs, energy inputs, and economic costs by 12.18–28.57%, compared to FEM. The energy utilization efficiency, energy profitability, and energy productivity under AIM were improved by 11.30–12.61%. CH4 and N2O emissions and carbon footprint were reduced by 20.79%, 6.51%, and 16.39%, respectively. Compared with FEM, AIM can effectively improve the utilization efficiency of water and fertilizer resources and reduce carbon emissions. This study presents a mechanized water and fertilizer management approach suitable for large-scale rice production systems in China. By analyzing rice yield, resource utilization efficiency, and environmental benefits, AIM can serve as a crucial management strategy for enhancing productivity, economic returns, and environmental conservation within profitable rice production systems. In the future, further investigation into the impact of AIM on the microbial mechanisms underlying rice yield formation and greenhouse gas emissions is warranted.

The construction of highway microgrids is evolving into a new highway energy system that integrates “Source-Network-Load-Storage”. This paper provides a comprehensive evaluation of expressway microgrids from the perspective of transportation and energy integration. An index model is set up that considers the economy, technology, and environment. The grey evaluation method, on the strength of analytic hierarchy process–entropy weight method, shows that the integrated microgrid of “source-network-load-storage” promotes energy sustainability, supply reliability, and sustainable environmental development. When compared to different evaluation methods for microgrid planning schemes, our method yields the highest score of 0.9127, indicating superior results. This approach is suitable for the multicomponent evaluation system of expressway microgrids and allows for scientifically evaluating microgrid planning schemes.

This study takes the fruit of Rosa roxburghii Tratt (RRT) as a fermentation substrate and carries out a quantitative visual analysis of the domestic and foreign literature on screenings of five different lactic acid bacteria to obtain a fermentation broth. Systemic anti-photoaging effects are analyzed at the biochemical, cellular, and molecular biological levels. DPPH and ABTS free radical scavenging activities are used to verify the antioxidant capacity of the RRT fruit fermentation broth in vitro. Human embryonic skin fibroblasts (HESs) are used to establish a UVA damage model, and the antioxidant capacity of the RRT fruit fermentation broth is verified in terms of intracellular reactive oxygen species (ROS) and antioxidant enzyme activity. RT-qPCR and ELISA are used to detect the expression of TGF-β/Smad, MMPs, and the MAPK/AP-1 and Nrf2/Keap-1 signaling pathways in order to explore the anti-oxidation and anti-photoaging effects of the RRT fruit fermentation broth by regulating different signaling pathways. The results show that an RRT fruit fermentation broth can effectively protect cells from oxidative stress caused by UVA and has significant anti-photoaging effects, with the co-cultured Lactobacillus Yogurt Starter LYS-20297 having the highest overall effect.

During precision sowing, the contact process between the soil and seeds cannot be ignored. The constitutive relationship of soil is relatively complex, with characteristics such as high nonlinearity, while the contact mechanism between the soil and seeds is unclear. To better understand the contact between seeds and soil, it is necessary to establish a reasonable contact model. Ellipsoidal seeds, such as soybean, red bean, and kidney bean seeds, were adopted as research objects. In this paper, we used the discrete element method to establish an ellipsoidal seed–soil contact model. The JKR + bonding model was adopted for describing the adhesion between soil particles, and the Hertz–Mindlin new restitution (HMNS) model was used for ellipsoidal seed particles to eliminate the multiple contact point issue when modeling with the multi-sphere filling method. Moreover, both simulations and experiments were conducted to calibrate the interaction parameters between soil and seeds. The path of steepest ascent test and Box‒Behnken design (BBD) tests were also used, as well as direct shear tests. Thus, certain soil parameter values were obtained, namely the JKR surface energy was 4.436 J/m2, the normal stiffness per unit area was 2.86 × 106 N/m3, the shear stiffness per unit area was 5.54 × 105 N/m3, the critical normal stress was 1833 Pa, and the critical shear stress was 3332 Pa. In addition, the simulation parameters for ellipsoidal seeds were obtained from previous works. Moreover, to obtain more accurate ellipsoidal seed–soil interaction parameters, collision tests, static friction tests, and rolling friction tests were adopted. A single-factor test was used to calibrate the ellipsoidal seed–soil interaction parameters. The calibration results were as follows: the collision restitution coefficients of ellipsoidal seeds with soil were all 0.25. The static friction coefficient of soybeans with soil was 0.6, that of red beans with soil was 0.65, and that of kidney beans with soil was 0.5. The rolling friction coefficient of soybeans with soil was 0.1, that of red beans with soil was 0.14, and that of kidney beans with soil was 0.14. Finally, the rationality of parameter selection was verified through piling tests between ellipsoidal seeds and soil. The relative error of the angle of repose of soybean/soil was 2.99%, that of red bean/soil was 0.60%, and that of kidney bean/soil was 0.55%. Thus, the feasibility and rationality of the contact models between the ellipsoidal seeds and soil established in this paper, as well as the parameter selection, were verified.

The thermal problem of high-altitude airships has an essential impact on position control and energy system performance. Adjusting the airship’s attitude angle causes differences in thermal performance during position alterations. This paper studies an airship’s energy and thermal performance under variable attitudes. We establish an airship solar radiation and thermal model to analyze power output under different thermal conditions. The thermal performance of airships at varying pitch angles is investigated using computational fluid dynamic (CFD) software (Fluent V6.3.26). To determine the optimal distribution of pitch angles under various conditions, we have developed an optimization model that considers both the presence and absence of thermal influence. We have also assessed the impact of airship geometric parameters on the optimal pitch angle, considering the diversity of airship shapes. Our results demonstrate that pitch angle alterations significantly influence airships’ temperature and flow field distribution. But the degree of necessity of considering the thermal effect in calculating the optimal pitch angle distribution varies depending on the date and latitude, with the most vital need observed during low-latitude summer and the weakest during high-latitude winter. The findings of this research have significant reference value in selecting operation strategies and the control of operating performance for high-altitude airships.

Fruit snacks have become a popular and convenient snacking choice and have the potential to contribute to a well-balanced diet. However, the nutritional quality of fruit snack products has not yet been studied. The objective of the present study is to provide a nutritional assessment of the fruit snack product category. This study used the Mintel Global New Product Database to collect data about fruit snack products launched in the United States from 2017 to 2022. Fruit snack products (n = 2405) are divided into nine product categories based on product characteristics. Nutrition composition was assessed using a comprehensive score, Nutrient Rich Food (NRF) model, and by examining individual components (added sugar and fiber). The results show that dried fruit has the highest nutrient density, fiber content, and the lowest added sugar content. Conversely, fruit-flavored snacks have the lowest nutrient density, fiber content, and added sugar content. Currently, fruit puree, canned fruit with juice, and dried fruit are the only fruit snacks that meet the current recommendations set by the USDA Dietary Guidelines. Future directions for the fruit snack category should consider decreasing the added sugar content, increasing the fiber content, and enhancing their sensory profile to improve the overall nutrient density.

Sympatric distribution and temporal overlap of cryptic zooplankton species pose a challenge to the framework of the niche differentiation theory and the mechanisms allowing competitor coexistence. We applied the methods of phylogenetic analysis, DNA taxonomy, and statistical analysis to study the temporal distribution patterns of the cryptic B. calyciflorus species, an excellent model, in three lakes, and to explore the putative mechanisms for their seasonal succession and temporal overlap. The results showed that in the warm-temperate Lake Yunlong, B. fernandoi and B. calyciflorus s.s. underwent a seasonal succession, which was largely attributed to their differential adaptation to water temperature. In the subtropical Lake Jinghu, B. fernandoi, B. calyciflorus s.s., and B. dorcas exhibited both seasonal succession and temporal overlap. Seasonal successions were largely attributed to their differential adaptation to temperature, and temporal overlap resulted from their differential responses to algal food concentration. In the tropical Lake Jinniu, B. calyciflorus s.s. persisted throughout the year and overlapped with B. dorcas for 5 months. The temporal overlap resulted from their differential responses to copepod predation. These results indicated that the temporal distribution pattern of the cryptic B. calyciforus species and the mechanism that allows competitor coexistence vary with different climate zones.

The routine use of prosthetic hands significantly enhances amputees’ daily lives, yet it often introduces cognitive load and reduces reaction speed. To address this issue, we introduce a wearable semi-autonomous hierarchical control framework tailored for amputees. Drawing inspiration from the visual processing stream in humans, a fully autonomous bionic controller is integrated into the prosthetic hand control system to offload cognitive burden, complemented by a Human-in-the-Loop (HIL) control method. In the ventral-stream phase, the controller integrates multi-modal information from the user’s hand–eye coordination and biological instincts to analyze the user’s movement intention and manipulate primitive switches in the variable domain of view. Transitioning to the dorsal-stream phase, precise force control is attained through the HIL control strategy, combining feedback from the prosthetic hand’s sensors and the user’s electromyographic (EMG) signals. The effectiveness of the proposed interface is demonstrated by the experimental results. Our approach presents a more effective method of interaction between a robotic control system and the human.

Aiming to mitigate the impact of power fluctuation caused by large-scale renewable energy integration, coupled with a high rate of wind and solar power abandonment, the multi-objective optimal dispatching of a cascade hydro–wind–solar–thermal hybrid generation system with pumped storage hydropower (PSH) is proposed in this paper. Based on the proposed system, the scheduling operation strategy takes into account the complex restrictions of cascade hydropower as well as the flexibility of the PSH. According to various scenarios, the NSGA-II approach is adopted to address the optimization problem, minimizing the system’s residual load variation and operation cost. The Pareto solution sets are contrasted and evaluated, applying the TOPSIS with CRITIC weighting. Additionally, the scheduling output of thermal power, cascade hydropower, and PSH is given in terms of different scenarios. The results demonstrate that the allocation of PSH to a hybrid energy system can significantly reduce the operation cost and the fluctuation in the residual load.

Fault detection and state estimation play pivotal roles in ensuring the reliability, safety, and performance of automatic control systems [...]

In this study, we investigated the physiological response to low-temperature stress and comprehensively evaluated the cold resistance of green prickly ash germplasms. One-year-old branches of 23 green prickly ash varieties were used as experimental materials, three branches were selected from each variety, and three replicates of single branches were established. Subsequently, the physiological responses of the 23 green prickly ash germplasm resources to low-temperature stress were analyzed based on the relative conductivity (REC), osmotic adjustment substances, and antioxidant enzyme activities. We found that as the temperature decreased, the REC of each germplasm increased. The most rapid REC increase occurred from 0 to −10 °C and continued to gradually gently increase from −10 to −30 °C. The lethal dose-50 temperature (LT50) of the germplasms was between 3.16 and −12.37 °C. The top three cold-resistant varieties were TJ, SCHJ, and CJ, and the last three cold-resistant varieties were EWJ, DYSJ, and HYXJ. The results of a correlation analysis revealed a significant correlation between superoxide dismutase (SOD) activity and REC, between REC and free protein, and between SOD activity and catalase. The results of the PCA revealed that the first category includes 5 pepper varieties of CJ, LFJ, and XYTJ with higher cold-resistance score indexes; the second category includes 13 pepper varieties of YQ2 H, WCFZ, and TZJ with appropriate scores; and the third category includes 5 pepper varieties of HYXJ, HNJ, and DYSJ with lower scores. Cluster analysis was performed to classify the cold-resistance physiological indices, and four groups were obtained. The most cold-resistant groups included CJ and LFHJ, whereas the most cold-sensitive groups included HYXJ, DYSJ, and HNJ. Finality, the subordinate function method was used to determine the cold resistance from strong to weak. The varieties with the strongest cold resistance were LFJ, EWJ, and CJ, and the weakest varieties were DYSJ, YQ1H, and HYXJ. The strongest cold-resistant varieties were LFHJ and CJ, followed by DYSJ, YQ1H, and HYXJ. Based on multiple lines of evidence, the most cold-resistant varieties were CJ and LFJ, while the most cold-sensitive varieties were DYSJ and HYXJ. In conclusion, in this study, we elucidated the low-temperature tolerance of different varieties of green prickly ash, and varieties with high cold resistance were selected. These findings provide theoretical guidance and technical support for the screening of cold-resistant green prickly ash germplasms, which will facilitate their introduction to northern China.

An expressway microgrid can make full use of renewable resources near the road area and enable joint carbon reduction in both transportation and energy sectors. It is important to research the optimal construction mode and capacity configuration method of expressway microgrid considering the carbon trading and carbon offset mechanism. This paper establishes a design model for an expressway microgrid considering the operating features of each component in the microgrid under two patterns of grid-connected/islanded and two types of AC/DC. The goal of the proposed model is to minimize the annualized comprehensive cost, which includes the annualized investment cost, operational cost, and carbon trading cost. The model designates the optimal construction mode of an expressway microgrid, i.e., grid-connected or islanded, AC or DC. As a mixed integer nonlinear programming (MINLP) problem, the proposed model can be solved in a commercial solver conveniently, such as GUROBI and CPLEX. The validity and practicality of the proposed model have been demonstrated through case studies in several different application scenarios, which also demonstrate the necessity of considering carbon trading mechanisms in the design model.

Glufosinate is a broad-spectrum herbicide used to control most weeds in agriculture worldwide. Goosegrass (Eleusine indica L.) is one of the top ten malignant weeds across the world, showing high tolerance to glufosinate via different mechanisms that are not yet fully understood. This study revealed that nitrogen metabolism could be a target-resistant site, providing clues to finally clarify the mechanism of glufosinate resistance in resistant goosegrass populations. Compared to susceptible goosegrass (NX), the resistant goosegrass (AUS and CS) regarding the stress of glufosinate showed stronger resistance with lower ammonia contents, higher target enzyme GS (glutamine synthetase) activity, and lower GOGAT (glutamine 2-oxoglutarate aminotransferase) activity. The GDH (glutamate dehydrogenase) activity of another pathway increased, but its gene expression was downregulated in resistant goosegrass (AUS). Analyzing the transcriptome and proteome data of goosegrass under glufosinate stress at 36 h showed that the KEGG pathway of the nitrogen metabolism was enriched in glufosinate-susceptible goosegrass (NX), but not in glufosinate-resistant goosegrass (CS and AUS). Several putative target genes involved in glufosinate stress countermeasures were identified. This study provides specific insights into the nitrogen metabolism of resistant goosegrass, and gives a basis for future functional verification of glufosinate-tolerance genes in plants.

A novel approach was developed to detect bed fluidity in gas–solid fluidized beds using diffuse reflectance near-infrared (NIR) spectroscopy. Because the flow dynamics of gas and solid phases are closely associated with the fluidization state, the fluidization quality can be evaluated through hydrodynamic characterization. In this study, the baseline level of NIR spectra was used to quantify the voidage of the fluidized bed. Two indicators derived from the NIR baseline fluctuation profiles were investigated to characterize bed fluidity, named bubble proportion and skewness. To establish a robust fluidity evaluation method, the relationships between the indicators and bed fluidity were investigated under different conditions firstly, including static bed height and average particle size. Then, a generalized threshold was identified to distinguish poor and good bed fluidity, ensuring that the probability of the α- and β-errors was less than 15% regardless of material conditions. The results show that both indicators were sensitive to changes in bed fluidity under the investigated conditions. The indicator of skewness was qualified to detect bed fluidity under varied conditions with a robust threshold of 1.20. Furthermore, the developed NIR method was successfully applied to monitor bed fluidity and for early warning of defluidization in a laboratory-scale fluidized bed granulation process.

This study explored the overall visual elements of arcade buildings and streetscapes from the perspective of tourists and then evaluated their influence on the identity and emotion of places. The scope of the research was to take the arcade building in the port area of Shantou Small Park in Guangdong, China, and apply the eye-tracking experiment method and semantic difference method. This entailed collecting the eye-tracking data of 16 people, implementing 334 questionnaires for evaluation, verifying the correlation between the visual elements and place identity emotions, and then screening out the visual elements that affect place identity through correlation analysis and multiple linear regression analysis. The results show that plaque text morphological richness (p = 0.045 < 0.05, and the regression coefficient B = 0.146), the color brightness of plaque text (p = 0.031 < 0.01, and the regression coefficient B = 0.171), window morphological richness (p = 0.038 < 0.05, and the regression coefficient B = 0.106), window color brilliance (p = 0.047 < 0.01, and regression coefficient B = 0.094), and plant color brilliance (p = 0.029 < 0.05, and the regression coefficient B = 0.154) are five visual element evaluation factors that have a significant correlation with the identity and emotion of places. Although the fineness of architectural decoration is negatively correlated with place identity, it is not obviously significant. The research results provide reference for the visual control design of arcade buildings.

Microalloying and heat treatment have been regarded as an efficient way to get higher wear resistance in high manganese steel, and multiscale precipitates can be obtained randomly by the aging process; however, most of the previous work on heat treatment was more concerned with peak aging time and not the synergistic mechanism of different sized precipitates. Here, we propose a novel wear-resistant mechanism by multiscale precipitates regulated via a retrogression and re-aging (RRA) process. Micron, submicron, and nano precipitates are obtained by the RRA process and jointly form micro-scale ultrafine precipitation zones (MUPZs), which can protect the matrix surface and reduce the abrasive embedded probability, thus ameliorating the micro-cutting and micro-plowing mechanisms. This novel wear-resistant mechanism induced by MUPZs shows better effect under high impact energy due to sufficient work hardening caused by the interaction between dislocations and multi-scale precipitates in MUPZs. This work was investigated using SEM, EDS, and TEM, combined with mechanical properties and impact abrasive wear tests.

Dongcai is loved for its delicious flavor and nutritional value. The microorganisms in Dongcai play a vital role in their flavor, quality, and safety, and the microbial communities of Dongcai vary greatly from region to region. However, it remains unknown what the predominant microorganisms are in different traditional Dongcai and how they affect its flavor. The objective of this study is to explore the microbial diversity of traditional fermented Dongcai in three representative Chinese regions (Tianjin, Sichuan, and Guangzhou) and further assess their microbial functions. The microbial diversity of fermented Dongcai in Guangdong has the lowest diversity compared to fermented Dongcai in Sichuan, which has the highest. The distribution of the main genera of fermented Dongcai varies from region to region, but Carnimonas, Staphylococcus, Pseudomonas, Sphingomonas, Burkholderia-Caballeronia-Paraburkholderia, and Rhodococcus are the dominant genera in common. In addition, halophilic bacteria (HAB, i.e., Halomonas Bacillus, Virgibacillus, etc.) and lactic acid bacteria (LAB, i.e., Weissella and Lactobacillus) are also highly abundant. Of these, Burkholderia-Caballeronia-Paraburkholderia, Rhodococcus, Sphingomonas, Ralstonia, and Chromohalobacter are dominant in the Sichuan samples. In the Tianjin samples, Lactobacillus, Weissella, Virgibacillus, Enterobacter, Klebsiella, and Pseudomonas are the most abundant. Predictions of microbial metabolic function reveal that carbohydrates, amino acids, polyketides, lipids, and other secondary metabolites are abundantly available for biosynthesis. In addition, the different flavors of the three types of Dongcai may be due to the fact that the abundance of HAB and LAB shows a significant positive correlation with the amounts of important metabolites (e.g., salt, acid, amino nitrogen, and sugar). These results contribute to our understanding of the link between the distinctive flavors of different types of Dongcai and the microorganisms they contain and will also provide a reference for the relationship between microbial communities and flavor substances in semi-fermented pickles.

Magnesium silicate hydrate (M-S-H) cement, a type of green building material, has poor volume stability (i.e., large shrinkage deformation), which limits its application. As a new type of admixture, the behavior of a shrinkage-reducing admixture (SRA) in M-S-H cement has not been studied. Therefore, in this research, the effect of SRA on the shrinkage properties of the M-S-H cement system was evaluated. The mechanism of SRA was investigated by surface tension measurement, hydration heat testing, thermogravimetric analysis, and pore structure analysis. Experimental results indicate that SRA can reduce the shrinkage of the M-S-H mortar, and the optimal effect is exerted when the dosage is 3.0%, drying shrinkage decreases by 22.6%, and autogenous shrinkage decreases by 60% on day 28. However, it may also adversely affect strength development. The presence of SRA in M-S-H cement can reduce pore solution surface tension, delay hydration, and maintain relative humidity within the slurry, which can be maintained at 82.0% on day 28. It can also increase pore size and porosity. The inhibitory effect of SRA on the shrinkage of M-S-H mortar is valuable for its future practical applications.

Strontium, the main component of radioactive nuclear wastewater, is characterized by a high fission yield and an extended half-life. It is easily absorbed by the human body, thus greatly threatening the environment and the human body. In this study, a mesoporous composite phase sodium superionic conductor (NVP@NMP) was synthesized by the droplet template method, and the rapid capture of Sr2+ from wastewater was achieved by constructing a nano-heterogeneous interface to increase the ion diffusion rate. NVP@NMP showed efficient and rapid removal of strontium ions in adsorption kinetics, isothermal adsorption, solution pH, and interfering ions concentration tests, especially using the equilibrium time of 2 min for strontium absorption by NVP@NMP and a maximum theoretical adsorption capacity of 361.36 mg/g. The adsorption process was spontaneous, endothermic, and feasible. At higher concentrations of other competing ions (Na, K, Ca, Mg, and Cs), the adsorbent exhibited higher selectivity towards Sr2+.TEM, XPS, and XRD analyses revealed that ion exchange was the main mechanism for the NVP@NMP ultrafast adsorption of Sr2+. In this research, we investigated the feasibility of ultrafast strontium capture by sodium superionic conductor structured phosphates and explained the ultrafast strontium adsorption mechanism of NASICON materials through XPS.

The interspersed railway track is an enhanced timber railway track, spot-replacing damaged wooden sleepers with new concrete sleepers to improve the bearing capacity of existing railway lines. Although this interspersed solution is characterised by low cost and short maintenance time, the interspersed tracks have worse stability than concrete tracks and can deteriorate quickly when exposed to extreme weather conditions such as heavy rains and floods. In many cases, heavy rains and floods are accompanied by strong winds. Ballast washaway can often be observed under flood conditions while the mass of trains is unevenly distributed on two rails due to the effect of lateral wind load and rail irregularities. The current work is the first in the world to investigate the collective multi-hazard effects of ballast washway and uneven axle loads on the vulnerability of conventional and interspersed railway tracks using nonlinear FEM software, STRAND 7. The train bogie is modelled by two sets of point loads. The maximum displacement, bending moment and twists have been studied to evaluate the worst condition. The novel insights will help the railway industry develop proper operations of interspersed railway tracks against naturally hazardous conditions.

To address the problem of herbicide residues exceeding the safety standard due to continuous spraying of herbicides on open-field cabbage, we propose an intermittent weed spraying control method integrating cabbage position, cabbage canopy size, and spraying machine operation speed. It is based on an early-stage cabbage target identification method obtained in the early stage and the operation requirements in open-field cabbage. Built with a C37 controller, a stable pressure spray system and an intermittent weed spraying control system for open-field cabbage, an integrated system was designed. Experimental verification was carried out through measurement indexes such as spraying precision, herbicide saving rate, herbicide efficacy, and herbicide residue. Since the industry is faced with a status quo of a lack of relevant operational norms and national standards for the precise weed spraying operation mode, this paper provides a relatively perfect experiment and evaluation method for this mode. The experimental results on the accuracy of weed spraying at different speeds showed that the mean absolute error (MAE), root mean square error (RMSE), and average spray cabbage coverage rate (ASCCR) of intermittent weed spraying increased, but the average effective spray coverage rate (AESCR) decreased with increasing operation speed. When the working speed was 0.51 m/s, the MAE and RMSE of intermittent weed spraying were less than 2.87 cm and 3.40 cm, respectively, and the AESCR was 98.4%, which verified the feasibility of operating the intermittent weed spraying of cabbage. The results of a field experiment showed that the average weed-killing rate of intermittent weed spraying for open-field cabbage was 94.8%, and the herbicide-saving rate could reach 28.3% for a similar weeding effect to that of constant-rate application, which not only met the needs of intermittent weed spraying in open-field cabbage but also had great significance for improving the herbicide utilization rate. Compared with the constant-rate application method, the herbicide residue concentration detected using intermittent weed spraying for cabbage decreased by 66.6% on average, which has important research significance and application value for ensuring the normal growth of crops and the safety of agricultural products.

SiC substrates have outstanding advantages over traditional materials in power device application, and are mainly prepared by a physical vapor transport method (PVT). Whether the PVT furnace works by resistance heating or induction heating, both face the problem of the deterioration of growth conditions during a long-term process. The relative position of the thermal field directly affects the crystal growth conditions, but the law of specific influence and the change in physical environment inside the thermal field have not been made sufficiently clear and lack systematic research. Therefore, SiC single crystal growth, with different directions and rates in the direction of movement of the heating module, was modeled using a simulation method, and the law of variation of the physical field, including heat flux, temperature, powder porosity and growth rate parameters under different schemes, was analyzed. The study indicates that the decay of raw materials is the primary reason why growth conditions cannot be maintained. The results verified that different coils’ modes of movement have different effects on the improvement or adjustment of SiC crystals’ growth conditions. Under the same temperature control conditions, the coils’ movement rates of 200 μm/h, 0, −200 μm/h and −400 μm/h correspond to the average growth rates of 140, 152, 165 and 172 μm/h, respectively. The results show that downward displacement of the coils is beneficial in compensating for the deterioration of growth conditions, but it is easier to form convex surfaces and is not conducive to expanding diameter growth. This also verifies that the desired crystal growth state can be obtained by adjusting the position of the thermal field.

Oxidative stress is an important factor on both aging and disease. Among foods endowed with beneficial healthy properties, rice is a very useful material, not only because it has a good amino acid ratio and produces antioxidant peptides through microbial fermentation, but also for its inexpensive availability. In this study, rice was treated with Lactobacillus plantarum, and the resulting mixture of small peptides with less than 11 amino acids (RFP) was extracted and purified from the fermentation broth. Subsequently, the antioxidant activity of RFP was assessed using the chemical model, cell biology, and animal model methods. RFP enhanced the expression of the antioxidant enzyme genes downstream of the KEAP1−NRF2/ARE pathway by promoting nuclear factor−erythroid 2−related factor 2 (NRF2) nuclear translocation while simultaneously removing lipid oxidation products and excess free radicals. These results suggest that RFP is a potential substance for resisting aging and disease caused by oxidative stress.

Due to large line spacing and planting distances, the adoption of continuous and uniform pesticide spraying in vegetable farming can lead to pesticide waste, thus increasing cost and environmental pollution. In this paper, by applying deep learning and online identification methods, control technology for target-oriented spraying is studied with cabbages as the research object. To overcome motion blur and low average precision under strong light conditions during the operation of sprayers, an innovative YOLOV5 model implanted with a transformer module is utilized to achieve accurate online identification for cabbage fields under complex environments. Based on this concept, a new target-oriented spray system is built on an NVIDIA Jetson Xavier NX. Indoor test results show that the average precision is 96.14% and the image processing time is 51.07 ms. When motion blur occurs, the average precision for the target is 90.31%. Then, in a field experiment, when the light intensity is within the range of 3.76–12.34 wlx, the advance opening distance is less than 3.51 cm, the delay closing distance is less than 2.05 cm, and the average identification error for the cabbage diameter is less than 1.45 cm. The experimental results indicate that changes in light intensity have no significant impact on the identification effect. The average precision is 98.65%, and the savings rate reaches 54.04%. In general, the target-oriented spray system designed in this study achieves the expected experimental results and can provide technical support for field target spraying.

The hand-transmitted vibration generated by extravehicular activity (EVA) power tools has an important impact on the health of astronauts and the efficient completion of maintenance tasks when astronauts use EVA power tools for on-orbit maintenance. Based on the hand-transmitted vibration zero-gravity simulation test platform to measure the vibration response of the EVA power tool to human hands. Given the influence of the length of the operating rod and the number of non-detaching fastening devices on daily vibration exposure when astronauts wear extravehicular spacesuit gloves, a second-order polynomial model and a quadratic cumulative nonlinear model of daily vibration exposure are established. The experimental results show that the second-order polynomial model is more explanatory and predictive of the test data in the scope of the test. The R-values of the palm and opisthenar prediction model are 0.9930 and 0.9940 respectively, and the RMSEs are 7.973×10−4 m/s2 and 1.034×10−3 m/s2. The quadratic cumulative nonlinear model can accurately predict the vibration exposure of the hand outside the scope of the test. This study can provide theoretical reference and data support for the prediction of vibration exposure generated by astronauts using the EVA power tools during on-orbit maintenance.

Malania oleifera Chun et S.K. Lee is an endangered woody oil tree that produces nervonic acid, which is closely related to brain development. The phenotypic variation and diversity in some representative traits in natural populations are poorly understood. To investigate phenotypic variation, diversity and their relationship with geoclimatic factors, we evaluated 21 traits of 97 sampled individuals from seven natural populations. Coefficient of variation for 21 traits widely ranged from 0.05 (shape index of fruit) to 0.62 (water content of dry kernel), with an average of 0.18. The Shannon–Wiener indices ranged from 1.91 (water content of dry kernel) to 2.06 (leaf length and leaf width), with an average of 1.94. The variation of 20 traits was significantly influenced by the population effect (p < 0.05). The 21 traits were reduced to six principal components, which collectively accounted for 86.64% of the total phenotypic variation. The seven population was mainly divided into two groups: Group I, which included four populations distributed throughout the southern region and having wider and shorter leaves, larger fruit transverse diameters, and higher content of fatty acid and nervonic acid in the kernel, and Group II included the left populations with relative opposite characteristics to those in Group I. Trees with shorter leaves tend to produce oblate shape and heavier dried kernel, yielding more fatty acid and nervonic acids, and population-level pairwise kernel morphological distance were positively correlated with fatty acid distance (Mantel r = 0.39, p < 0.05). Annual average humidity was strongly positively correlated with leaf index (length/width, r = 0.78) but had a negative correlation with the kernel dry weight (r = −0.84). The shape of the kernel gradually altered from oblate to globose as longitude and rainfall increased. The environment became colder as latitude increased, resulting in a steady decrease in fatty acid content. No significant isolation by climatic and geographical distance was found for morphological and fatty acid variability. These results can have an important implication for genetic improvement, diversity conservation and resource management of the species in the future.

Three-dimensional (3D) point cloud maps are widely used in autonomous driving scenarios. These maps are usually generated by accumulating sequential LiDAR scans. When generating a map, moving objects (such as vehicles or moving pedestrians) will leave long trails on the assembled map. This is undesirable and reduces the map quality. In this paper, we propose MapCleaner, an approach that can effectively remove the moving objects from the map. MapCleaner first estimates a dense and continuous terrain surface, based on which the map point cloud is then divided into a noisy part below the terrain, the terrain, and the object part above the terrain. Next, a specifically designed moving points identification algorithm is performed on the object part to find moving objects. Experiments are performed on the SemanticKITTI dataset. Results show that the proposed MapCleaner outperforms state-of-the-art approaches on all five tested SemanticKITTI sequences. MapCleaner is a learning-free method and has few parameters to tune. It is also successfully evaluated on our own dataset collected with a different type of LiDAR.

The spatial distribution of water storage capacity has always been the critical content of the study of saturation-excess runoff. Xin’anjiang model uses the water storage capacity curve (WSCC) to characterize the distribution of water storage capacity for runoff yield calculation. However, the mathematical and physical foundations of WSCC are unclear, which is impossible to simulate runoff generation with complex basins accurately. To fill this gap, we considered the dominant role of basin physical characteristics in water storage capacity and developed a new integrated approach to solve the spatial distribution of water storage capacity (L-WSCC) to account for the spatiotemporal dynamics of their impact on runoff generation. The main contribution of L-WSCC was to confer WSCC more physical meaning and the spatial distribution of water storage capacity was explicitly represented more accurately, so as to better express the runoff generation and provide a new approach for runoff yield calculation in non-data basin. L-WSCC was applied to Misai basin in China and promising results had been achieved, which verified the rationality of the method (the mean Nash–Sutcliffe efficiency (NSE):0.86 and 0.82 in daily and hourly scale, respectively). Compared with WSCC, the performance of L-WSCC was improved (mean NSE: 0.82 > 0.78, mean absolute value of flood peak error (PE): 12.74% < 21.66%). Moreover, the results of local sensitivity analyses demonstrated that land-use and land cover was the major driving factor of runoff yield (the change of mean absolute error (ΔMAE): 131.38%). This work was significant for understanding the mechanisms of runoff generation, which can be used for hydrological environmental management and land-use planning.

Electronic-grade polysilicon is the cornerstone of the information industry. Considering the demand for this material in the semiconductor industry, any technological improvement has great potential benefits. Due to the quality requirements of electronic polysilicon, its preparation process is characterized by low raw material utilization and high cost. Simply increasing the deposition rate by increasing the chemical reaction rate will easily lead to a reduction in the proportion of dense materials. For the first time, a coupled furnace scheme is proposed to improve the utilization of raw materials while maintaining the same deposition quality. The deposition conditions on the surface of silicon rods with different base plate designs were modeled and analyzed using the software PolySim, and a design characterized by a high flow rate and the use of 9 mm and 15 mm nozzles was selected for the coupling scheme. In coupling mode, the simulation results show that the utilization of raw materials is increased by 17.5%, and the deposition rate is increased by 44.9%, while the deposition quality and uniformity remain approximately unchanged. The results show that the coupling scheme with high feed flow is beneficial for significantly improving the deposition conditions and the utilization rate of raw materials, which also provides guidance for material preparation processes with similar principles.

Surface-enhanced Raman scattering (SERS) provides an unprecedented opportunity for fingerprinting identification and trace-level detection in chemistry, biomedicine, materials, and so on. Although great efforts have been devoted to fabricating sensitive plasmonic nanomaterials, it is still challenging to batch-produce a SERS substrate with high sensitivity, good reproducibility, and perfect recyclability. Here, we describe a facile fabrication of three-dimensional (3D) hierarchical Au/CuS nanocomposites, in which high-density Au nanotips enable highly SERS-active sensing, and the well-defined microflower (MF) geometry produces perfect signal reproducibility (RSD < 5%) for large laser spot excitations (>50 μm2), which is particularly suitable for practical on-site detection with a handheld Raman spectrometer. In addition, a self-cleaning ability of this Au/CuS Schottky junction photocatalyst under sunlight irradiation allows complete removal of the adsorbed analytes, realizing perfect regeneration of the SERS substrates over many cycles. The mass-production, ultra-sensitive, high-reproducibility, and fast-recyclability features of hierarchical Au/CuS MFs greatly facilitate cost-effective and field SERS detection of trace analytes in practice.

As an ecological consequence of intensified anthropogenic activities, more frequent extreme rainfalls have resulted in significant increases in water levels and discharge in southwestern China. This phenomenon presents a significant challenge in flood risk and ecological management. Land use is one of the major factors significantly affecting the flooding process, and it is inextricably tied to the ecological risk of floods. Hence, flood risk estimates based on land use are essential for flood control and land use planning. In this study, a coupled hydrologic–hydraulic model was developed to analyze the relationship between flood ecological risk and land use in order to provide new insights into current flood risk management practices. Ten real flood events (of different magnitudes) in the Zhaojue river basin (650 km2) were chosen to evaluate the credibility and performance of the coupled model’s application. Promising results were obtained, with sufficient reliability for flood risk assessment purposes. The results of our flood risk analysis also indicated that the model effectively reproduced overland flow and competently accounted for flood evolution. This work is significant in the understanding of the mechanism of the flood process and its relationship with land use, and it can be used in decision support for the prevention and mitigation of flood disasters and for land use planning.

Micro-cooling is a growing trend in the field of turbine blade cooling. Technical difficulties in the experiments of large-aspect-ratio rectangular microchannels that are commonly used in the turbine blades cause the rareness of related literature. In this study, the flow characteristics and heat transfer performance of the microchannels with and without semi-ellipsoidal protrusions, whose height is 0.6 mm and width is 9 mm, are numerically investigated. In the microchannel without protrusions, when 2214 < Re < 3589, the velocity has a Λ-shaped distribution, resulting in a Λ-shaped Nu distribution on the wall. When Re > 3760, it is worth noting that from the sidewall to the middle of the channel, Nu first decreases and then increases. In the microchannel with protrusions, when Re < 1214, the turbulence formed by the protrusion is almost all behind it and does not spread to both sides. When 1214 < Re < 2374, the turbulence caused by the protrusions gradually spreads to the middle and both sides of the channel with the increase in Re. When 2374 < Re < 3815, the turbulence caused by two columns of protrusions meet in the middle of the channel and forms stronger turbulence downstream. When Re > 3815, the flow is all turbulent. The protrusions enhance the irreversibility of heat transfer and friction. The performance evaluation criteria (PEC) increases first and then decreases with Re and the maximum value is 1.80 at Re = 2004. In this work, the details that are difficult to obtain in experiments are fully analyzed to provide suggestions for the design of micro-cooling structures in gas turbine blades.

In interstitial-free (IF) steel with a certain microtexture, the micro-orientation of grains is essential to understand the occurrence of hydrogen-induced cracking in body-centered cubic (BCC) structural steels. In this study, the hydrogen embrittlement (HE) susceptibility of IF steels was determined by slow strain rate tensile (SSRT) tests and hydrogen microprinting (HMT) experiments from the perspective of crystal orientation. The strength of the specimen with hydrogen was slightly higher than that without hydrogen, while the ductility and toughness were drastically reduced by hydrogen charging during the SSRT test. The HE susceptibility was characterized by the loss of elongation (Iδ) and toughness (Iψ), with losses of 46.3% and 70%, respectively. The microstructural observations indicate that cracks initiated along grains oriented in the {100} || normal direction (ND), and grain boundaries (GBs) around {100}||ND were prone to be enriched in hydrogen atoms; that is, {100} || ND showed poor resistance to intergranular cracking and susceptible to hydrogen segregation. HMT was used to confirm the above viewpoints. Meanwhile, the statistical results showed those high-angle misorientations of 50–60° deviation are the locations most vulnerable to fracture.

UVA can cause oxidative stress and photoaging of cells. We established a UVA-induced oxidative stress model of human fibroblasts and focused on the antioxidant and anti-photoaging ability of Lactobacillus plantarum fermented Rhodiola rosea. Compared with the unfermented Rhodiola rosea, Lactobacillus plantarum fermented Rhodiola rosea has better DPPH free radical and hydroxyl free radical scavenging ability, significantly reduces the content of reactive oxygen species (ROS), and improves the antioxidant level. Further studies have shown that the Lactobacillus plantarum fermented Rhodiola rosea can activate the Nrf2/Keap1 signaling pathway and up-regulate heme oxygenase-1 (HO-1), NAD(P)H quinone dehydrogenase 1 (NQO1), catalase (CAT) and glutathione Peptide peroxidase (GSH-Px), and protect fibroblasts from oxidative stress caused by UVA. On the other hand, Lactobacillus plantarum fermented Rhodiola rosea significantly reduces the activity of metalloproteinases in the cell, thereby increasing the collagen and elastin in the cell, alleviating the photoaging caused by UVA. Finally, we concluded that the antioxidant capacity and anti-photoaging ability of Lactobacillus plantarum fermented Rhodiola rosea are better than that of unfermented Rhodiola rosea.

This work first synthesized a series of linear polyesters by step-growth polycondensation, then an amino-terminated hydrophilic polyether was grafted to the polyester as side-chains through aza-Michael addition to prepare a self-dispersible, non-ionic waterborne comb-like polyester (NWCPE). In contrast to traditional functionalization methods that usually require harsh reaction conditions and complex catalysts, the aza-Michael addition proceeds efficiently at room temperature without a catalyst. In this facile and mild way, the NWCPE samples with number-average molecular weight (Mn) of about 8000 g mol−1 were obtained. All dispersions showed excellent storage stability, reflected by no delamination observed after 6 months of storage. The NWCPE dispersion displayed better hydrolysis resistance than an ionic waterborne polyester, as was indicated by a more slight change in pH value and Mn after a period of storage. In addition, the film obtained after the NWCPE dispersion was cross-linked with the curing agent, it exhibited good water resistance, adhesion, and mechanical properties.

No reference image quality assessment (NR IQA) aims to develop quantitative measures to automatically and accurately estimate perceptual image quality without any prior information about the reference image. In this paper, we introduce two low-level feature distributions (TLLFD) based method for NR IQA. Different from the deep learning method, the proposed method characterizes image quality with the distributions of low-level features, thus it has few parameters, simple model, high efficiency, and strong robustness. First, the texture change of distorted image is extracted by the weighted histogram of generalized local binary pattern. Second, the Weibull distribution of gradient is extracted to represent the structural change of the distorted image. Furthermore, support vector regression is adopted to model the complex nonlinear relationship between feature space and quality measure. Finally, numerical tests are performed on LIVE, CISQ, MICT, and TID2008 standard databases for five different distortion categories JPEG2000 (JP2K), JPEG, White Noise (WN), Gaussian Blur (GB), and Fast Fading (FF). The experimental results indicate that TLLFD method achieves superior performance and strong generalization for image quality prediction as compared to state-of-the-art full-reference, no reference, and even deep learning IQA methods.

Bletilla striata is a terrestrial orchid with high ornamental and medicinal values that is widely interplanted in bamboo forests. However, little is known about the effects of bamboo forest type and density on the growth of B. striata and its symbiotic relationship with root endophytic fungi. In this study, the growth state of B. striata, the community composition and diversity of its root endophytic fungal, and the fungal nutritional function were investigated in Phyllostachys edulis, P. iridescens and P. glauca forests with three densities. We found that the type and density of the bamboo forest had significant effects on the growth of B. striata, with the biomass, leaf width, root quantity and width being the highest in the low-density of the P. edulis forest. The community composition and abundance of root endophytic fungi in B. striata varied among different bamboo forests and densities, with P. edulis and P. iridescens forests dominated by Basidiomycota and Serendipita, while P. glauca prevailed by Ascomycota and Dactylonectria. The trophic modes of root endophytic fungi were also affected by forest types and densities. The abundance of symbiotroph fungi was the highest in P. edulis and P. iridescens forests and greatly varied with density gradient, and saprotrophic fungi comprised the highest proportion in the Ph. glauca forest. These results provide basic data for further research and the configuration between bamboo species and terrestrial orchids.

Long Term Evolution-Metro (LTE-M), as a special communication system for train control, has strict requirements on adjacent channel interference (ACI). According to the 3rd Generation Partnership Project (3GPP) protocol of the European Telecommunications Standards Institute (ETSI) standards, this paper presents the required isolation degree for LTE-M systems to resist ACI. Aiming at the scenario of leaky cable transmission and antenna transmission adopted by the underground LTE-M system of the subway, the isolation degree required for LTE-M system deployment is deduced by combining the channel description with the principle of ACI. For the coexistence of a LTE-M system and an adjacent cellular system in a subway ground scenario, the Monte-Carlo (MC) method is used to simulate several conceivable scenarios of the LTE-M system and the adjacent frequency cellular system. In addition, the throughput loss of the LTE-M system is estimated by considering signal to interference plus noise ratio (SINR). Simulation results demonstrate that adjacent frequency user equipment (UE) has negligible small interference with the LTE-M underground system when using the leaky cable radiation pattern, whereas for the LTE-M ground system, the main interference comes from the adjacent frequency UE to the LTE-M base station (BS). Finally, interference avoidance solutions are presented, which can be utilized as a reference in the design and deployment of LTE-M systems in the rail transit environment.

The objective of this paper is to accurately measure the vibration response of tools and hands by simulating the hand-held power tools, which are operated by astronauts wearing extravehicular spacesuit gloves under microgravity conditions. The total vibration value and the daily vibration exposure of the subject’s hand are obtained. The results show that the opisthenar is more sensitive to the vibration frequency less than 200 Hz. After frequency weighting, the vibration exposure in the composite state of wearing an unpressurized spacesuit glove on the opisthenar is 23.6% greater than the vibration exposure of the palm, and for the bare hand, the percentage is 25.1% under the same condition. Because the operation time of tightening a screw is longer than that of loosening, the tightening operation performed by wearing spacesuit gloves produces 15.7% more mean vibration exposure on the palm and opisthenar than the loosening operation. The results of vibration transmissibility characterized by the total vibration weighted method and the total vibration unweighted method are 0.039 and 0.094, respectively. In comparison with bare hands, the mean daily vibration exposure on the palm and opisthenar in the composite state by wearing spacesuit gloves is 16.3% less, indicating that the unpressurized spacesuit gloves have an effect on vibration reduction. The research reveals the law of hand-transmitted vibration caused by the coupling of the extravehicular activities (EVA) power tools and spacesuit gloves, and provides a novel method for further similar tests and verification of hand-held EVA power tools.

The exopolysaccharide secreted by Lacticaseibacillus paracasei subsp. paracasei SS-01 strain (LP-EPS) is isolated and purified from yogurt. It is a polysaccharide with a branched and multi-stranded structure, which exists in a smooth rod-like or cloud-like state, and possesses a good thermal stability and a molecular weight of 49.68 kDa (±4.436%). LP-EPS shows a high antioxidant capacity, anti-inflammatory and anti-sensitizing activity during in vitro experimental studies, with half clearance (IC50) rates of 0.449, 1.314, and 2.369 mg/mL for the ABTS, DPPH, and OH radicals, respectively, and a half inhibition rate (IC50) of hyaluronidase of 1.53 mg/mL. A cell-based assay, enzyme-linked immunosorbent assay (ELISA), and quantitative real-time fluorescence PCR (qRT-PCR) show that LP-EPS effectively treats or ameliorates the skin inflammatory responses triggered by UVB irradiation, as evidenced by a highly significant decrease in the secretion of inflammatory factors by human skin keratinocytes (HaCaT), and a highly significant downregulation of the mRNA expression of MAPK/AP-1 pathway cytokines.

Spherical Janus micromotors (SJMs) have attracted much attention, and their high-speed motion is highly desired due to their various potential applications. However, the conventional template-deposition method often leads to an active Pt coating with a smooth surface, which is unbeneficial to speed enhancement in terms of catalytic reaction. Here, a facile surface roughening method is presented to fabricate the Pt-polystyrene (PS) SJMs with rough Pt surface (or Ptr-PS SJMs) by plasma-etching the PS colloidal monolayer and then depositing Pt. The Ptr-PS SJMs can exhibit directional motion pushed by the Pt in the various H2O2 solutions, and they show much higher motion speeds than the Pt-PS SJMs with smooth Pt surfaces at the same H2O2 concentration. The Pt-pushed motion is related to the locally asymmetric catalytic reaction of the Pt coating on PS. The speed is also associated with the surface roughness of the Pt coating. The Pt film with a rough surface causes enhanced motion speed due to the improvement of reaction catalytic activity. This work presents a new route to enhancing the motor motion speed, which is of significance in designing micromotors with high-speed motion.

This paper reports on a proposed novel 3D-printed sandwich lattice model using a triply periodic minimal surface (TPMS) structure for meta-functional composite bridge bearings (MFCBBs). It could be implemented in bridge systems, including buildings and railway bridges. A TMPS structure offers a high performance to density ratio under different loading. Compared to typical elastomeric bridge bearings with any reinforcements, the use of 3D-printed TPMS sandwich lattices could potentially lead to a substantial reduction in both manufacturing cost and weight, but also to a significant increase in recyclability with their better mechanical properties (compressive, crushing, energy absorption, vibration, and sound attenuation). This paper shows predictions from a numerical study performed to examine the behaviour of a TPMS sandwich lattice model under two different loading conditions for bridge bearing applications. The validation of the modelling is compared with experimental results to ensure the possibility of designing and fabricating a 3D-printed TPMS sandwich lattice for practical use. In general, the compressive experimental and numerical load–displacement behaviour of the TPMS unit cell are in excellent agreement within the elastic limit region. Moreover, its failure mode for bridge bearing applications has been identified as an elastic–plastic and hysteretic failure behaviour under uniaxial compression and combined compression–shear loading, respectively.

The variations in the degradation of electrical characteristics resulting from different device structures for trench-gate SiC metal-oxide-semiconductor field effect transistors (MOSFETs) are investigated in this work. Two types of the most advanced commercial trench products, which are the asymmetric trench SiC MOSFET and the double-trench SiC MOSFET, are chosen as the targeted devices. The discrepant degradation trends caused by the repetitive avalanche stress are monitored. For the double-trench device, the conduction characteristic improves while the gate-drain capacitance (Cgd) increases seriously. It is because positive charges are injected into the bottom gate oxide during the avalanche process, which are driven by the high oxide electronic field (Eox) and the high impact ionization rate (I.I.) there. Meanwhile, for the asymmetric trench SiC MOSFET, the I–V curve under the high gate bias condition and the Cgd remain relatively stable, while the trench bottom is well protected by the deep P+ well. However, it’s threshold voltage (Vth) decreases more obviously when compared with that of the double-trench device and the inclined channel suffers from more serious stress than the vertical channel. Positive charges are more easily injected into the inclined channel. The phenomena and the corresponding mechanisms are analyzed and proved by experiments and technology computer-aided design (TCAD) simulations.

Additive manufacturing technologies, well known as three-dimensional printing (3DP) technologies, have been applied in many industrial fields, including aerospace, automobiles, shipbuilding, civil engineering and nuclear power. However, despite the high material utilization and the ability to rapidly construct complex shaped structures of 3D printing technologies, the application of additive manufacturing technologies in railway track infrastructure is still at the exploratory stage. This paper reviews the state-of-the-art research of additive manufacturing technologies related the railway track infrastructure and discusses the challenges and prospects of 3D printing technology in this area. The insights will not only help the development of 3D printing technologies into railway engineering but also enable smarter railway track component design and improve track performance and inspection strategies.

Afforestation is one of the most efficient ways to control land desertification in the middle section of the Yarlung Zangbo River (YZR) valley. However, the lack of a quantitative way to record the planting time of artificial forest (AF) constrains further management for these forests. The long-term archived Landsat images (including the Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+), and Operational Land Imager (OLI)) provide a good opportunity to capture the temporal change information about AF plantations. Under the condition that there would be an abrupt increasing trend in the normalized difference vegetation index (NDVI) time-series curve after afforestation, and this characteristic can be thought of as the indicator of the AF planting time. To extract the indicator, an algorithm based on the Google Earth Engine (GEE) for detecting this trend change point (TCP) on the maximum NDVI time series within the growing season (May to September) was proposed. In this algorithm, the time-series NDVI was initially smoothed and segmented into two subspaces. Then, a trend change indicator Sdiff was calculated with the difference between the fitting slopes of the subspaces before and after each target point. A self-adaptive method was applied to the NDVI series to find the right year with the maximum TCP, which is recorded as the AF planting time. Based on the proposed method, the AF planting time of the middle section of the YZR valley from 1988 to 2020 was derived. The detected afforestation temporal information was validated by 222 samples collected from the field survey, with a Pearson correlation coefficient of 0.93 and a root mean squared error (RMSE) of 2.95 years. Meanwhile, the area distribution of the AF planted each year has good temporal consistency with the implementation of the eco-reconstruction project. Overall, the study provides a good way to map AF planting times that is not only helpful for sustainable management of AF areas but also provides a basis for further research on the impact of afforestation on desertification control.

The rheological properties of ferrofluids are related to various applications, such as sealing and loudspeakers, and have therefore attracted widespread attention. However, the rheological properties and their influence on the mechanisms of perfluoropolyether oil (PFPE oil)-based ferrofluids are complicated and not clear. Here, a series of PFPE oil-based ferrofluids were synthesized via a chemical co-precipitation method, and their rheological properties were revealed, systematically. The results indicate that the prepared Zn-ferrite particles have an average size of 12.1 nm, within a range of 4–18 nm, and that the ferrofluids have excellent dispersion stability. The activity of the ferrofluids changes from Newtonian to non-Newtonian, then to solid-like with increasing w from 10 wt% to 45.5 wt%, owing to their variation in microstructures. The viscosity of the ferrofluids increases with increasing Mw (the molecular weight of base liquid PFPE oil polymer), attributed to the increase in entanglements between PFPE oil molecules. The magnetization temperature variation of Zn-ferrite nanoparticles and viscosity temperature variation of PFPE oil together contribute to the viscosity temperature change in ferrofluids. The viscosity of the ferrofluids basically remains unchanged when shear rate is above 50 s−1, with increasing magnetic field strength; however, it first increases and then levels off when the rate is under 10 s−1, revealing that the shear rate and magnetic field strength together affect viscosity. The viscosity and its alteration in Zn-ferrite/PFPE oil-based ferrofluids could be deduced through our work, which will be greatly significant in basic theoretical research and in various applications.