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In this work, a progressive micropunching technology was proposed to form complex shaped microparts using thin copper strip with a thickness of 200 μm. The mechanical properties, microstructure and texture of the annealed thin copper strip were systematically studied, and the quality of the formed microparts through both 1-step micropunching and progressive micropunching were evaluated and discussed. The results show that annealing temperatures of 500 and 600 °C are beneficial to improve the plasticity and formability of copper strips, thereby enhancing the dimensional and shape accuracy of formed complex shaped microparts. Compared with the formed products after 1-step micropunching, the smooth zone of the microparts by progressive micropunched increases by 25%. Also, progressive micropunching significantly improves the surface finish of the cross section of formed microparts. Overall, the proposed progressive micropunching process is functional to enhance the dimensional and shape accuracy of punched parts, exhibiting superiority in comparison with 1-step micropunching process.

Highlights This review summarizes the decade milestone advancement of defect-engineered g-C3N4 and emphasizes the roles of crystallinity and defect traps toward a more precise defective g-C3N4 “customization” in the future. A critical insight into the defect traps has been discussed in depth, probing the defect-induced states and photocarrier transfer kinetics of g-C3N4. The prospect and outlooking for precise defective g-C3N4 “customization” is proposed.

In this work, the formability of copper foils was analyzed based on a series of multi-step micro deep drawing (MMDD) tests. The copper foils were annealed at temperatures ranging from 300 to 700 °C for 5 min, followed by tensile tests and electron backscatter diffraction (EBSD) tests for the exploration of mechanical behavior and microstructural characterization of annealed specimens. The results show that the as-received copper foils exhibit poor formability and cannot form micro cups during MMDD. When the annealing temperature attains 500 °C, a homogeneous microstructure was formed inside copper foils, enhancing the formability of materials and improving the surface quality of formed products. Nevertheless, both the elongation and tensile strength decrease dramatically due to the easy occurrence of incoordination deformation in coarse grain bands with further increase in annealing temperature to 700 °C. Consequently, marked wrinkling is generated on the surface of drawn cups and obvious thinning occurs at the nose radius region due to metal flow. In addition, the results show that the E texture component within the copper foils is favorable for MMDD. Overall, an optimal annealing temperature of 500 °C is obtained with improved formability of copper foils and forming quality of drawn cups.

The phenomenon that CuO resistors encounter gas changes opens the prelude to metal oxide semiconductors (MOSs) as gas sensing. From 1953 to 1968, the research and production of MOS gas sensors were unified, but the gas-sensitive materials used at that time were mostly bulk. Owing to the continuous exploration of material science and technology, nanomaterials began to flourish at the end of the 20th century. The emergence of nanomaterials promoted the development of gas sensors to a certain extent because the properties of MOSs are material dependent. Over the past few decades, nanomaterial applications in the field of gas sensing have led to the preparation of MOS-based gas sensors that can identify harmful gases in different environments with excellent characteristics, such as high sensitivity, selectivity, and stability, along with fast response/recovery. However, with the improving precision of gas detection, single-metal MOS materials have faced difficulty in meeting gas-sensing requirements. Therefore, preparing MOS materials into various nanostructures is desirable to improve the detection limit and sensitivity of gas sensors. When compared to nanomaterials with multiple-dimensional structures, one-dimensional counterparts exhibit improved gas-sensitive performance for H2S due to their larger specific surface area, good crystallinity, unique electron transport characteristics, and controllable grain size. Therefore, in this study, H2S gas is mainly focused, and the characteristics of nanomaterials with different one-dimensional structures based on MOSs are reviewed along with the research progress of H2S gas sensors based on nanomaterials with one-dimensional structures. Herein, regarding gas sensing, various properties of common one-dimensional nanostructures, such as nanowires, nanorods, nanofibers, and nanotubes, are thoroughly analyzed and summarized. The importance of H2S gas detection in military, medical, industrial, and everyday applications is briefly discussed, along with the common preparation methods for nanomaterials with one-dimensional structures. In addition, the working mechanism of p-type and n-type MOS as gas sensors is discussed. Furthermore, the influence of MOS-based nanomaterials with one-dimensional structures on H2S gas–sensitivity properties and mechanisms was investigated. Simultaneously, based on the gas-sensitive properties of nanomaterials with one-dimensional structures, the practical application characteristics of various nanomaterials with one-dimensional structures are highlighted. Finally, the performance improvement and future application prospects of MOS-based nanomaterials with one-dimensional structures for H2S gas sensors are discussed.

Trajectory-following control is the basis for the practical application of an articulated virtual rail train transportation system. In this paper, a planar nonlinear dynamics model of an articulated vehicle is derived using the Euler–Lagrange method. A trajectory-following control strategy based on the first following point is proposed, and a feedback linearization control algorithm is designed based on the vehicle dynamics model to achieve the trajectory following of the rear vehicle. Based on the target trajectory formed by the first following point and measured by virtual sensors, a vector analysis method grounded in geometric relationships is proposed to solve in real time for the desired position, velocity, and acceleration of the vehicle. Finally, a MATLAB/SIMPACK dynamics virtual prototype is established to test the vehicle’s trajectory-following effectiveness and dynamics performance under lane change and circular curve routes. The results indicate that the control algorithm can achieve trajectory following while maintaining good vehicle dynamics performance. It is robust to variations in vehicle mass, vehicle speed, tire cornering stiffness, and road friction coefficient.

A novel treatment process that involves solution treatment, cryogenic pre-stretching, and artificial aging was applied to strengthen Al-Cu-Li alloy without ductility sacrificing in this work. The influence of pre-stretching deformation at ambient (RT, 25 °C) and cryogenic (CT, −196 °C) temperatures on dislocation configuration, precipitation behaviour, and after-aging mechanical properties of AA2195 was systematically investigated. Compared with conventional RT-stretched sample, the after-aging yield strength (YS) of CT-stretched sample was increased from 618 MPa to 655 MPa with ductility of 11.6%. The increased strength resulted from the combination of strain hardening and precipitation strengthening. The activated immovable dislocations on {100}Al during CT-stretching obstructed the subsequent slip of following dislocations to grain boundaries, prevented the dislocations piling-up at grain boundaries, and facilitated the dislocation accumulation at grain interior. The increased dislocations density within grains not only provided higher strain hardening to the alloy but also promoted the nucleation of T1 phase in the matrix, which significantly increased the yield strength. Additionally, the reduction of grain boundary dislocations suppressed the precipitation of T1 at grain boundaries, which prevented the formation of precipitate-free zones (PFZs) and the stress concentration at grain boundary during deformation, enhancing the alloy ductility.

In this study, a numerical simulation model based on crystal plasticity theories was established in order to study the micro deep drawing (MDD) process of ferritic stainless steel (FSS) 430 foils (50 μm thickness). The numerical simulation results obtained using the crystal plasticity finite element method (CPFEM) match well with experimental values, which indicates that the CPFEM can be utilized to analyze the forming performance of FSS foils during MDD. The results show that optimal annealing temperatures are 850 and 900 °C, which benefits both the surface quality of drawn cups and the formability of FSS 430 foils. During MDD process, remarkable thinning occurs at the nose radius area while the maximum thickness is found at the cup mouth area due to metal flow. The thickness is reduced by about 10% at the nose radius area and increased by about 20% at the cup mouth area. It is also found that the surface quality of drawn cups can be improved by applying appropriate blank holding force during MDD process.

The tribological behavior of traditional oil-in-water (O/W) lubricants (1.0 wt.%) and nano-TiO2 additive lubricants (1.0–9.0 wt.%) during micro rolling of titanium foils were analyzed. In this study, the surface morphologies of titanium foils under various lubrication conditions were assessed, and the corresponding lubrication mechanisms were revealed. The tribological behavior of nano-TiO2 additive lubricants during micro rolling of titanium foils was also explored through a series of characterization methods. The utilization of nano-TiO2 additive lubricants in micro rolling reduces the surface roughness of titanium foils. Moreover, it effectively inhibits the generation of indentations and cracks during rolling processes, enhancing the surface quality of rolled specimens. Additionally, owing to the synergism of rolling, tribo-film, mending and polishing effects of the nanoparticles, both the rolling force and surface roughness were minimized by using lubricants containing 3.0 wt.% TiO2 nanoparticles. Overall, an optimal concentration (3.0 wt.%) of TiO2 nanoparticles in water-based nanolubricants was obtained with enhanced tribological properties and lubrication performance during micro rolling of titanium foils.

Lithium-ion batteries experience rapid temperature increases with a high risk of combustion and explosion during thermal runaway, and water mist has been considered as one of the most effective cooling strategies. The water mist field can be impacted by the safety valve airflow, subsequently affecting the cooling characteristics. In this paper, the water mist nozzle with a fixed working pressure is located 1 m above the 100 Ah LiFePO4 battery to suppress the thermal runaway, and the cooling characteristics under various stages have been compared and analyzed. The results show that the development of thermal runaway can be inhibited before thermal runaway is initiated, and the water mist presents a better cooling effect after the battery safety valve is opened. The critical accumulation heat density of 155 kJ/kg has been identified, which is the threshold for thermal runaway suppression. The confrontation between water mist and the flame has been analyzed, and the water mist droplets cannot fall on the battery surface, resulting in a poor cooling rate of 0.57 kW. This means the suppression effect of water mist will be affected by the airflow impact of the safety valve.

Abstract Water electrolysis is a sustainable and clean method to produce hydrogen fuel via hydrogen evolution reaction (HER). Using stable, effective and low-cost electrocatalysts for HER to substitute expensive noble metals is highly desired. In this paper, by using first-principles calculation, we designed a defect and N-, S-, P-doped penta-graphene (PG) as a two-dimensional (2D) electrocatalyst for HER, and its stability, electronic properties and catalytic performance were investigated. The Gibbs free energy (ΔG H), which is the best descriptor for the HER, is calculated and optimized, the calculation results show that the ΔG H can be 0 eV with C2 vacancies and P doping at C1 active sites, which should be the optimal performance for a HER catalyst. Moreover, we reveal that the larger charge transfer from PG to H, the closer ΔG H is to zero according to the calculation of the electron charge density differences and Bader charges analysis. Ulteriorly, we demonstrated that the HER performance prefers the Volmer–Heyrovsky mechanism in this study.

In order to efficiently investigate the effect of the mesoscale heterogeneity of a concrete core and the randomness of circular coarse aggregate distribution on the stress wave propagation procedure and the response of PZT sensors in traditional coupling mesoscale finite element models (CMFEMs), firstly, a mesoscale homogenization approach is introduced to establish coupling homogenization finite element models (CHFEMs) with circular coarse aggregates. CHFEMs of rectangular concrete-filled steel tube (RCFST) members include a surface-mounted piezoelectric lead zirconate titanate (PZT) actuator, PZT sensors at different measurement distances, a concrete core with mesoscale homogeneity. Secondly, the computation efficiency and accuracy of the proposed CHFEMs and the size effect of representative area elements (RAEs) on the stress wave field simulation results are investigated. The stress wave field simulation results indicate that the size of an RAE limitedly affects the stress wave fields. Thirdly, the responses of PZT sensors at different measurement distances of the CHFEMs under both sinusoidal and modulated signals are studied and compared with those of the corresponding CMFEMs. Finally, the effect of the mesoscale heterogeneity of a concrete core and the randomness of circular coarse aggregate distribution on the responses of PZT sensors in the time domain of the CHFEMs with and without debond defects is further investigated. The results show that the mesoscale heterogeneity of a concrete core and randomness of circular coarse aggregate distribution only have a certain influence on the response of PZT sensors that are close to the PZT actuator. Instead, the interface debond defects dominantly affect the response of each PZT sensor regardless of the measurement distance. This finding supports the feasibility of stress wave-based debond detection for RCFSTs where the concrete core is a heterogeneous material.

The gut microbiome has been reported to be associated with obesity; here, the authors show that there are sex-specific differences in the relationship between gut microbes and abdominal obesity.

In order to evaluate the surface quality of ferritic stainless steel (FSS) sheets tensile deformation, a crystal plasticity (CP) model, in which the constitutive laws were incorporated with the consideration of the heterogeneous distribution of the properties of grains, was established to analyse the effect of texture, grain sizes and initial surface roughness on the surface roughness evolution of FSS sheets. The electron backscatter diffraction (EBSD) tests were performed to characterise the texture and the grains. A tensile test of the represent volume was simulated and further verified by experimental results. The numerical simulation results indicate that the surface roughness is dependent almost linearly on the average grain size. The {001}〈110〉 and the {112}〈110〉 components induce remarkable undulation on the surface of FSS sheets during uniaxial tension. The surface topology of FSS sheets after tensile deformation are obtained using 3D laser scanning microscope, which shows an agreement with the simulated results. Keywords: Ferritic stainless steel, Surface roughness evolution, Surface topography, Crystal plasticity model.

A comparative study has been carried out to assess the effect of rolling and annealing processes on ridging generation of ferritic stainless steels (FSSs) 430 and 430LR after tensile deformation. The results show that FSS 430LR has better ridging resistance owing to the refinement of microstructure and crystallographic texture optimisation. A 30% reduction of ridging height can be achieved using FSS 430LR compared to FSS 430 after tension. Optimal reduction during cold rolling benefits the microstructural refinement and surface quality improvement of FSSs 430 and 430LR. Both theoretical calculations and experimental results indicate that the {1 1 2} and the {0 0 1} components are responsible for ridging in the FSSs after tension. Through preventing the formation of coarse bands and grains with the {0 0 1} component inside the FSSs, the ridging resistance of both FSSs 430 and 430LR can be improved. Keywords: Annealing, Ferritic stainless steel, Grain refinement, Reduction, Ridging

Water-based lubricants with different fractions of TiO2 nanoparticles ranging from 1.0 to 9.0 wt.% were utilized to study the lubrication mechanisms during micro rolling tests and the tribological behaviour of nanolubricants during the micro rolling of copper foils. The results indicate that the application of TiO2 nanolubricants remarkably improves the surface quality of rolled copper foils during rolling processes. For lubricants with inadequate TiO2 nanoparticles, it is found that few TiO2 nanoparticles enter the contact regions between the rolls and foils, causing insufficient lubrication during rolling processes. Instead, for lubricants with excessive TiO2 nanoparticles, obvious agglomeration occurs at the contact regions and promotes the generation of voids on the surface of the rolled foils, thereby deteriorating the surface quality of the rolled copper foils. In addition, it is found that the surface quality of rolled foils is improved by utilizing a large reduction ratio. Overall, the fraction of 3.0 wt.% TiO2 nanolubricants is optimal to improve the lubrication conditions at the contact regions, thereby improving the surface quality of the rolled copper foils.

Here, we propose an optical bistable device structure with a few layers of graphene oxide integrated in the metal-dielectric-metal based asymmetric nanocavity. Through the light confinement in the nanocavity, the third order nonlinear absorption of graphene oxide can be significantly enhanced, which experimentally delivers low-threshold optical bistability at the visible wavelength of 532 nm with only 267 KW/cm2 intensity. In addition, the switching threshold can be further reduced via increasing the graphene oxide thickness, hence paving a new way for achieving tunable optical bistable devices at visible light frequencies.

Abstract Background Tuberculosis remains a serious threat to human health as an infectious disease in China. Henan, a most populated province in China, has a high incidence of tuberculosis (TB). Though the genetic diversity of Mycobacterium tuberculosis (MTB) has been investigated in many regions, there have been only a few studies on the molecular characteristics and drug resistance phenotypes in Henan. This is the first study on the genetic profile of MTB from Henan. Methods A total of 668 MTB isolates from various areas were genotyped with spoligotyping and 26-locus MIRU-VNTR (classical 24-locus MIRU-VNTR and 2 other loci). The association between TB spoligotype signatures and drug-resistant profiles was analysed. Results Our data revealed that MTB isolates circulating in Henan had a high degree of genetic variation. The Beijing family was the most predominant genotype (83.53%,n = 558), and the typical Beijing type(ST1) was the major sublineage (81.73%,n = 546). In total,668 isolates were divided into 567 different types, forming 38 clusters (2–15 isolates per cluster), and 529 unique types by 26-locus MIRU-VNTR analysis. There was no correlation between the Beijing family and gender, age at diagnosis or treatment history, whereas the Beijing family was significantly associated with all four first-line drug resistance and multidrug-resistant phenotypes. For these samples, 15 of 26 MIRU-VNTR loci had high or moderate discriminatory power according to the Hunter-Gaston discriminatory index. A combination of the 10 most polymorphic loci had similar discriminatory power as the 26-locus set. Conclusion The Beijing genotype is the most prevalent family. Ten-locus MIRU-VNTR in combination with spoligotyping can efficiently classify the molecular type of MTB in Henan Province.

Transparent YAG crystals are ubiquitous in phosphors, scintillators and lasers, but are complex and costly to make. Here, the authors use a one-step pressureless crystallization of bulk glass to make a transparent biphasic YAG nanoceramic that can be doped for optical applications.

Abstract Background Genotyping of the rs174547 polymorphism in the fatty acid desaturase 1 gene (FADS1) shows that it is associated with the FA composition of plasma phospholipids and lipid metabolic indices among several ethnic groups. However, this association requires further confirmation in the Chinese population, and little is known about the effect of polymorphisms in fatty acid-related genes on body fat distribution. Methods Anthropometric measurements of 951 Chinese adults aged 18–79 were obtained and body fat distribution was estimated using dual-energy X-ray absorptiometry. The FA composition of plasma phospholipids was measured by gas chromatography. Multiple linear regression assessed whether the rs174547 genotype was associated with FA composition, body fat distribution, and metabolic traits in additive, dominant, and recessive models. Results The rs174547 C minor allele was associated with a higher proportion of linoleic acid, lower arachidonic acid and docosahexaenoic acid, as well as lower delta-6-desaturase and delta-5-desaturase activity. Female C allele carriers had lower android fat percentages and lower levels of low-density lipoprotein-cholesterol, while male C allele carriers had lower gynoid fat percentages and higher triglyceride after adjusting for age, income, BMI, behavioral risk factors, and regional fat percentages. Conclusion An association of FADS1 rs174547 with the FA composition of plasma phospholipids was identified among this Chinese adult population. The association with body fat distribution and lipid metabolic indices differed between men and women, which might explain sexual differences in body fat distribution and lipid metabolism.

To meet rising energy demands, power plant operations will expand, influencing the interactions between the water–energy nexus and society. However, a major challenge is integration of social dimensions within electricity generation. To address this, we generate a baseline dataset using US public data (2014–2019) from the Energy Information Administration and US Bureau of Labor Statistics. We identify the rate of energy consumed, CO2, SO2 and NOx emissions generated, and water used per MWh net electricity as well as employee wellbeing per unit MW capacity during electricity generation. Rates of energy consumption (MMBtu/MWh) decreased 4.9%, but water consumption and withdrawal (m3/MWh) both increased 0.93% and 0.31%, respectively. Emissions of CO2, SO2 and NOx decreased 22.64%, 75% and 25% MT/MWh, respectively. Thermoelectric cooling withdrawal and consumption is led by natural gas (50.07%, 38.31%), coal (29.61%, 25.07%), and nuclear energies (13.55%, 18.99%). Electric power generation contributes 0.06 injuries–illnesses/TWh and 0.001 fatalities/TWh, of which fossil fuels contributed 70% and 15%, respectively. Fossil fuels led in average annual employment (0.02 employees/MW) with low cost salaries (USD 0.09/MW) likely due to high collective capacity, which is declining. Estimated rates in this study and framework will aid power industry transition and operational decision makers.

BACKGROUND: Exposure to sunlight may decrease the risk of several diseases through the synthesis of vitamin D, whereas solar radiation is the main cause of some skin and eye diseases. However, to the best of our knowledge, the association of sun-induced skin damage with mortality remains unknown. METHODOLOGY/PRINCIPAL FINDINGS: Subjects were 8472 white participants aged 25-74 years in the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. Cardiovascular disease mortality, cancer mortality, and all-cause mortality were obtained by either a death certificate or a proxy interview, or both. Actinic skin damage was examined and recorded by the presence and severity (absent, minimal, moderate, or severe) of overall actinic skin damage and its components (i.e., fine telangiectasia, solar elastosis, and actinic keratoses). Cox regression and Kaplan-Meier methods were applied to explore the associations. A total of 672 cancer deaths, 1500 cardiovascular disease deaths, and 2969 deaths from all causes were documented through the follow-up between 1971 and 1992. After controlling for potential confounding variables, severe overall actinic skin damage was associated with a 45% higher risk for all-cause mortality (95% CI: 1.22, 1.72; P

Men tend to have more upper body mass and fat than women, a physical characteristic that may predispose them to severe motor vehicle crash (MVC) injuries, particularly in certain body regions. This study examined MVC-related regional body injury and its association with the presence of driver obesity using both real-world data and computer crash simulation.Real-world data were from the 2001 to 2005 National Automotive Sampling System Crashworthiness Data System. A total of 10,941 drivers who were aged 18 years or older involved in frontal collision crashes were eligible for the study. Sex-specific logistic regression models were developed to analyze the associations between MVC injury and the presence of driver obesity. In order to confirm the findings from real-world data, computer models of obese subjects were constructed and crash simulations were performed. According to real-world data, obese men had a substantially higher risk of injury, especially serious injury, to the upper body regions including head, face, thorax, and spine than normal weight men (all p

Following the works by Wiegmann-Zabrodin, Elbau-Felder, Hedenmalm-Makarov, and others, we consider the normal matrix model with an arbitrary potential function, and explain how the problem of finding the support domain for the asymptotic eigenvalue density of such matrices (when the size of the matrices goes to infinity) is related to the problem of Hele-Shaw flows on curved surfaces, considered by Entov and the first author in 1990-s. In the case when the potential function is the sum of a rotationally invariant function and the real part of a polynomial of the complex coordinate, we use this relation and the conformal mapping method developed by Entov and the first author to find the shape of the support domain explicitly (up to finitely many undetermined parameters, which are to be found from a finite system of equations). In the case when the rotationally invariant function is βz^2, this is done by Wiegmann-Zabrodin and Elbau-Felder. We apply our results to the generalized normal matrix model, which deals with random block matrices that give rise to *-representations of the deformed preprojective algebra of the affine quiver of type Â_{m-1}. We show that this model is equivalent to the usual normal matrix model in the large N limit. Thus the conformal mapping method can be applied to find explicitly the support domain for the generalized normal matrix model.

Background: The distribution of hepatic echinococcosis (HE) is extensive, significantly impacting public health and economic development. Therefore, analyzing global collaboration networks and tracking developmental trends over the past four decades are crucial. This study aimed to demonstrate collaboration in the field of HE and explore key topics and future directions. Materials and Methods: Bibliometric analyses were conducted using CiteSpace, Bibliometrix package of R, and VOSviewer software on HE-related studies from the Web of Science Core Collection published before 1 August 2023. Results: This study identified 2605 records published in 196 journals by 9860 authors from 2607 institutes in 90 countries. Publications significantly notably increased in 2021. Developing countries like Turkey and China made notable contributions, while developed countries like the USA had higher average citation rates. The largest nodes in every cluster of the collaboration network were Hacettepe University, Tehran University, Xinjiang Medical University, Salford University, and the University of Pavia, and the topproducing authors were Wen H, Vuitton DA, Gottstein B, and Craig PS. Keyword co-occurrence analysis suggested that surgical techniques and novel drugs targeting combined immune checkpoints are the main therapeutic approaches in the future. Conclusion: Although developing countries had significantly contributed to publications on HE, the citation rate for individual articles from developed countries was significantly higher. Additionally, advancements in surgical techniques and novel drugs targeting combined immune checkpoints may emerge as the next research focus and developmental direction. [ABSTRACT FROM AUTHOR]