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Highly ordered periodic macroporous structures have been extensively utilized to significantly enhance the photocatalytic activity. However, constructing 3D interconnected ordered porous ternary nanostructures with highly crystalline frameworks remains a formidable challenge. Here, we introduce the design and fabrication of 3D interconnected periodic macroporous NaNbO3(PM NaNbO3) to effectively increase the density of surface-active sites and optimize the photogenerated carrier-transfer efficiency. By incorporating Pt as a cocatalyst, PM NaNbO3exhibits an exceptional photocatalytic hydrogen generation rate of 10.04 mmol h–1g–1, which is approximately six and five times higher than those of calcined NaNbO3(C–NaNbO3) and hydrothermal NaNbO3(H–NaNbO3), respectively. This outstanding performance can be attributed to the synergistic effects arising from its well-interconnected pore architecture, large surface area, enhanced light absorption capability, and improved charge carrier separation and transport efficiency. The findings presented in this study demonstrate an innovative approach toward designing hierarchically periodic macroporous materials for solar-driven hydrogen production.

In order to solve the uniqueness of the compliance equations and each notch profile, a curvature-adjustable multiple-axis flexure hinge with complex notch profiles is designed and investigated based on Bézier curve in this paper. The hinge can evolve into multiple-axis flexure hinges with single and hybrid, symmetric and asymmetric notch profiles composed of the ellipse, circle, hyperbola and parabola. In addition, analytical compliance equations in six degrees of freedom based on the Castigliano’s Second Theorem are proposed. Then, a simplified notch profile classification method based on a binary quadratic implicit equation is proposed. Moreover, analytical compliance equations are validated by finite element analysis. The maximum relative error between the finite element analysis and the analytical results is 6.07%. Finally, the compliance, precision of rotation and stress are investigated based on structural parameters. The results show that the change in the rotation centre does not significantly affect the axial and bending compliance for the flexure hinge with a specific single and flush Bézier curve notch profile. Moreover, the flexure hinge with a notch profile consisting of ellipse and hyperbola has the highest rotational precision. The proposed curvature-adjustable multiple-axis flexure hinge can provide more compliance options for the design of compliant mechanisms.

Engineering targeted and reliable charge transfer pathways in multiphase photocatalysts remains a challenge. Herein, we conceptualize the Cd@CdS-ZnO/reduced graphene oxide (rGO)/ZnS heterostructures coupled with reliable carrier migration channels and visible-light response antennas by building rGO-integrated electrochemical nanoreactors and an ion-exchange process. In this ternary catalyst, the Cd clusters and rGO perform as charge relays to boost carrier transport via the Z-scheme route and accelerate photogenerated carriers to react with surface-adsorbed substances. Meanwhile, thanks to CdS, the heterostructures have photocatalytic properties under visible light illumination and can also inhibit self-corrosion by shielding Cd clusters to avoid disrupting charge transfer channels. Therefore, the special heterostructure demonstrates fascinating photocatalytic hydrogen production activity without the intervention of cocatalysts. This work provides a feasible protocol for improving the interfaces between metals and semiconductors to achieve efficient photocatalytic hydrogen generation.

• A facile and scalable spray-drying method has been developed to prepare NVCP@C material, which exhibits three stable voltage platforms and manifests a high electrochemical performance (175 mAh g–1). • In-situ XRD reveals that the NVCP@C exhibits solid-solution and two-phase reaction mechanisms during the charge/discharge processes. • Full cells assembled by HC anode and NVCP@C cathode exhibit a long cycling performance (70% after 1000 cycles at 2000 mA g–1). Due to its abundant sodium content and low cost, sodium-ion battery (SIB) has become an effective substitute and supplement for lithium-ion batteries, which has a broad development prospect in large-scale energy storage systems. Na-super-ionic conductor (NASICON) structural materials have stable 3D skeleton structures and open Na+ transport channels, which is a very promising SIB cathode material. But in the typical NASICON material Na 3 V 2 (PO 4) 3 (NVP), the number of electrons involved in NVP per formula unit is less than 2 at the stable voltage window, which limits the further improvement of battery performance. In this work, we report another NASICON structured Na 3 V 4/3 Cr 2/3 (PO 4) 3 @C (NVCP@C), which is obtained by Cr-doped NVP through spray drying. By taking full advantage of the voltage platforms of V5+/4+, V4+/3+, and V3+/2+ in the window of 1.5–4.4 V, NVCP@C delivered a high discharge capacity (175 mAh g–1) and durable cyclability (86% capacity retention for 2000 cycles). In-situ X-ray diffraction results demonstrate that the reversible structural evolution accompanies by solid-solution reaction and two-phase reaction mechanisms co-exist during charge/discharge processes. When coupled with Na+ pre-embedded hard carbon (HC), the assembled NVCP@C//HC full cell delivers a high capacity (105 mAh g–1) and long cycling performance (70% after 1000 cycles). This Cr-doped NVP method offers new insights into the design of high-energy NASICON-structured cathode materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Direct laser assisted machining (DLAM) is an effective way to improve the machinability of superalloys. It makes important progress compared to conventional laser assisted machining that enable the heating and cutting simultaneously during machining process. In the present work, improved DLAM based on the cubic zirconia tool is developed. By utilizing the Cubic Zirconia tool, improved DLAM has higher applicability and less cost. For the first time, DLAM cutting tests on Al 7075-T6 and Ti-6Al-4V are performed varying the cutting speeds and laser output powers. Cutting forces, surface roughness, and chip morphology are observed and compared. Finite element simulation is performed to estimate the cutting temperature for all cutting conditions. The study's results suggest that the DLAM with cubic zirconia tool could improve the cutting of alloys by less cutting forces and smoother surface finish. The work provides significant insight into the cutting mechanism of DLAM.

The undulating coal seam floor in a mine leads to the complicated posture of the hydraulic supports. The existing methods for monitoring the pose of hydraulic supports have a poor monitoring effect, and are especially characterized by a lack of support position information. Therefore, this article proposes a relative pose reconstruction method for hydraulic supports driven by digital twins. First, the pose plane and relative pose matrix of the hydraulic support are defined to describe the pose state of the support by analyzing the pose deviation between adjacent supports. Then, a digital twin system is built for a hydraulic support model, and a pose deduction method based on ray detection is proposed. The accurate position and attitude of the hydraulic support are deduced in the virtual space driven by actual laser sensor information, and 3-D pose reconstruction is realized. Finally, a relative pose reconstruction experiment of the hydraulic support model is designed and conducted. The results show that the relative pose data obtained by the virtual reconstruction method are very close to the experimental measurements, and the highest reconstruction accuracy is found to be 97.44%. The feasibility of the laser sensor layout scheme and the virtual reconstruction method of the pose of the hydraulic support is proven. This method provides a new way to monitor the pose of hydraulic supports, and can provide a reference for the support operation of hydraulic supports in the real fully mechanized mining process.

The armored face conveyor (AFC) lacks autonomous propulsion ability and is limited by the flexible connection of the coal seam undulation and dumbbell pin during the propulsion process. The real-time monitoring of the AFC faces the two issues of dynamic changes in the coal seam and missing information. To address these issues, this article proposes an AFC pose deduction method based on digital twins and spatiotemporal characteristics. The method involves the virtual reconstruction of the working face based on spatial working condition information and the compensation of missing information using 2-D light detection and ranging (LiDAR) point cloud information. Then, based on the operation information of the shearer, the pose of the AFC is deduced by analyzing the point cloud information for the transfer mechanism and the dynamic changes of the coal seam. Fusion deduction is achieved by building adjacent knife-pushing scenes and dynamic cutting scenes, and an optimization design method is used to integrate the positioning results of multiple scenes. The inverse solution process of the transfer mechanism is then implemented to achieve AFC pose deduction. Experiments were conducted in a laboratory environment to verify the accuracy and real-time performance of the AFC pose deduction method. The results demonstrate the feasibility of the proposed method, which provides new ideas for the real-time monitoring of AFCs and a reference for the development of underground intelligence.

A compact fiber optic hydrogen sensing system employing self-referenced configuration and controllable light heating technologies, is proposed and experimentally demonstrated with ultra-high sensitivity and wide dynamic range of hydrogen concentration detection. This sensing probe, consisting of nano WO3-Pd2Pt-Pt composite films and single mode fiber inscribed with two Bragg gratings, is principally based on the gasochromic effect of sensitive films. Signal-to-noise ratio of this system can be significantly enhanced with peak intensity of high reflective fiber Bragg grating (I1, FBG1 written in flat wavelength range of light source) and background intensity (I2, at a spectral distance of 1nm on the red side of FBG1) as reference intensity and sensing intensity respectively. A 980 nm laser and proportion integration differentiation (PID) controller were employed to ensure the hydrogen sensitive film working at an optimized temperature of 80 °C. Hydrogen concentration detection from 0.5 to 12000 ppm in air was achieved by utilizing this sensing system. Experimental results demonstrate the resolution of this hydrogen sensing system can reach 0.2 ppm within range of 1 to 1000 ppm hydrogen exposure. Moreover, this sensor can present a quick response time of less than one second towards 4000 ppm hydrogen in air. Furthermore, the stability of this sensor can be greatly enhanced with controllable optical heating system. The approach proposed in this work can greatly improve the performance of hydrogen sensor, which is very beneficial to its potential application in hydrogen-related facilities.

Photocatalytic technology has made a series of breakthroughs in environmental remediation, but the degradation performance of persistent heavy metal ions and organic pollutants is not particularly excellent. In addition, the layered structure of bismuth oxyhalides (BiOX, X = I, Br, and Cl) has been a popular material for photodegradation and photoelectrochemistry. Accordingly, with a view to construct a suitable band structure and control the surface structure, it is necessary to develop a strategy to synthesize a BiOCl1–xInsolid solution with halogen vacancies. In this study, halogen vacancies are in situ introduced into the BiOCl1–xInsolid solution through constructing chemical bonds between the hydroxyl groups in glycerol and the I ions during the growth process. The band of the halogen-vacancy BiOCl1–xInsolid solution is widened and active sites centered at halogen vacancies are formed in the direction favorable for the photocatalytic reaction, resulting in enhanced performance in the reduction of Cr(VI) and the oxidation of phenol. The results obtained can provide a new idea for the design of efficient photocatalysts by controlling the formation of halogen vacancies.

Disodium carboxymethyl trithiocarbonate (D8) is an effective depressant for the flotation separation of stibnite and pyrite, but its inhibitory mechanism is still unclear. Hence, in this study, the flotation separation performance and inhibition mechanism of D8 were investigated through micro-flotation experiment, contact angle, infrared spectroscopy, adsorption capacity, and zeta potential measurement. The flotation experiment results showed that the D8 had a strong inhibitory ability on pyrite, while its inhibitory ability on stibnite was weak. Infrared and adsorption capacity experiment results indicated that D8 adsorbed onto the surface of pyrite and stibnite through physical adsorption; D8 and sodium diethyldithiocarbamate competitively adsorbed onto the surface of pyrite, which reduced the adsorption amount of sodium diethyldithiocarbamate. The measurement results of contact angle and zeta potential showed that the contact angle and zeta potential of pyrite were significantly reduced with the D8 adsorption, while after D8 acted on the surface of stibnite, the contact angle barely changed. Therefore, D8 enhanced the hydrophilicity of the pyrite surface and the pyrite was effectively depressed.

• A cost-effective strategy for constructing 3DOM g-C 3 N 4 /CdS was fabricated. • This heterostructure exhibits an enhanced photocatalytic H 2 evolution rate. • The 3DOM structure improves the light conversion and mass transfer efficiency. Carbon nitride (g-C 3 N 4) is an attractive photocatalyst but commonly suffers from high photogenerated electron-hole recombination rate, low specific surface area, and narrow visible-light response range. Herein, 3D ordered macroporous (3DOM) g-C 3 N 4 /CdS was constructed by a feasible and inexpensive synthesis strategy of using template and light-assisted methods to solve the above problems. The formed heterostructure with suitable morphology, band structure, and extended light absorption range is beneficial to promoting photocatalytic H 2 generation. 3DOM g-C 3 N 4 /CdS exhibits a high H 2 produce rate of 718.6 μmol h−1 g−1, which is 73.3 times higher than that of g-C 3 N 4 and 25.4 times higher than that of 3DOM g-C 3 N 4. The 3DOM structure can effectively increase the path length of light of g-C 3 N 4 , improve the light energy conversion efficiency, and shorten the carrier transport distance. CdS enhances visible-light response and produces many surface sites. Constructing a stable and tight interface between 3DOM g-C 3 N 4 and CdS can promote the migration of photogenerated electrons and holes and consequently the visible-light catalytic activity. This study offers an effective designing strategy for heterostructure photocatalysts to achieve high activity and stable solar H 2 production. [ABSTRACT FROM AUTHOR]

In order to improve the operational accuracy of microsurgical instruments and increase the success rate of surgery, a six-degree-of-freedom microsurgical instrument is designed and analyzed based on a rigid-flexible coupling multi-body system. First, an improved kinematic modeling method is proposed based on the pseudo-rigid body theory. Second, a rigid-flexible coupling simulation system is built to analyze the error sources in terms of the remote center of motion, preload, and side load. Then, the function of motion scaling, the accuracy of kinematic modeling, and the validity of the workspace are demonstrated by analyzing the workspace. In addition, the maximum stress is analyzed to ensure the safety and reliability of the application. The analysis results show that the improved kinematic modeling method improves the positioning accuracy by more than two times, and the root mean square error at the tool tip of the microsurgical instrument does not exceed 1 μm under a side load of 0.1 N. Finally, the experimental results show that the improved kinematic modeling method has higher pointing accuracy, and the maximum error does not exceed 10 μm. The designed microsurgical instrument can meet the requirements of surgical operations.

There is a perpetual pursuit for free-form glasses and ceramics featuring outstanding mechanical properties as well as chemical and thermal resistance. It is a promising idea to shape inorganic materials in three-dimensional (3D) forms to reduce their weight while maintaining high mechanical properties. A popular strategy for the preparation of 3D inorganic materials is to mold the organic–inorganic hybrid photoresists into 3D micro- and nano-structures and remove the organic components by subsequent sintering. However, due to the discrete arrangement of inorganic components in the organic-inorganic hybrid photoresists, it remains a huge challenge to attain isotropic shrinkage during sintering. Herein, we demonstrate the isotropic sintering shrinkage by forming the consecutive –Si–O–Si–O–Zr–O– inorganic backbone in photoresists and fabricating 3D glass–ceramic nanolattices with enhanced mechanical properties. The femtosecond (fs) laser is used in two-photon polymerization (TPP) to fabricate 3D green body structures. After subsequent sintering at 1000 °C, high-quality 3D glass–ceramic microstructures can be obtained with perfectly intact and smooth morphology. In-suit compression experiments and finite-element simulations reveal that octahedral-truss (oct-truss) lattices possess remarkable adeptness in bearing stress concentration and maintain the structural integrity to resist rod bending, indicating that this structure is a candidate for preparing lightweight and high stiffness glass–ceramic nanolattices. 3D printing of such glasses and ceramics has significant implications in a number of industrial applications, including metamaterials, microelectromechanical systems, photonic crystals, and damage-tolerant lightweight materials.

Cadmium sulfide is a potential candidate for photocatalytic water splitting. However, CdS nanoparticles have a high recombination rate of photoinduced carriers induced by aggregation. Therefore, decreasing the recombination rate and increasing the migration rate of photogenerated carriers are essential to drive the development and application of CdS in hydrogen production. In this study, we design CdS with a three-dimensional ordered macroporous (3DOM) structure using polymethylmethacrylate as a template. It not only retains the excellent visible light response of CdS but also improves the easy recombination of photogenerated carriers in CdS nanoparticles by taking advantage of the unique ability of mass transfer, charge separation, and migration in the 3DOM structure. Meanwhile, the highly ordered periodic structure of 3DOM CdS can produce a slow photon effect of photonic crystals to obtain more photoinduced carriers. In particular, we found that a suitable stop-band position is beneficial to maximize the utilization of the slow photon effect. The photocatalytic hydrogen evolution rate of Pt–CdS is considerably improved after constructing the 3DOM structure. This study provides a new design strategy of ordered macroporous sulfide catalysts to achieve high photocatalytic activity.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and the waning of vaccine-elicited neutralizing antibodies suggests that additional coronavirus disease 2019 (COVID-19) vaccine doses may be needed for individuals who initially received CoronaVac. We evaluated the safety and immunogenicity of the recombinant adenovirus type 5 (AD5)-vectored COVID-19 vaccine Convidecia as a heterologous booster versus those of CoronaVac as homologous booster in adults previously vaccinated with CoronaVac in an ongoing, randomized, observer-blinded, parallel-controlled phase 4 trial (NCT04892459). Adults who had received two doses of CoronaVac in the past 3–6 months were vaccinated with Convidecia (n= 96) or CoronaVac (n= 102). Adults who had received one dose of CoronaVac in the past 1–3 months were also vaccinated with Convidecia (n= 51) or CoronaVac (n= 50). The co-primary endpoints were the occurrence of adverse reactions within 28 d after vaccination and geometric mean titers (GMTs) of neutralizing antibodies against live wild-type SARS-CoV-2 virus at 14 d after booster vaccination. Adverse reactions after vaccination were significantly more frequent in Convidecia recipients but were generally mild to moderate in all treatment groups. Heterologous boosting with Convidecia elicited significantly increased GMTs of neutralizing antibody against SARS-CoV-2 than homologous boosting with CoronaVac in participants who had previously received one or two doses of CoronaVac. These data suggest that heterologous boosting with Convidecia following initial vaccination with CoronaVac is safe and more immunogenic than homologous boosting.

Perovskite solar cells (PSC) offer a promising solution for building integrated photovoltaics (BIPVs) due to its high photoelectric conversion efficiency (PCE). However, increasing the transparency of their functional layers dramatically decreases the PCE. Here, a computer controlled laser patterning method was proposed to directly turn PSC modules into semitransparent and with aesthetic artificial pattern, without additional complexities to the conventional PSCs fabrication process. A structured ST-PSC achieving a champion PCE of 17.5% with average visible transparency (AVT) of 18.2%, and a mini-module with 5 × 5 cm2delivering a PCE of 9.1% with AVT of 37.7% were demonstrated. Rationally designed aesthetic patterns were imprinted on mini-modules, achieving a PCE of 14.4%. These results reveal a new route for low-cost facile fabricating high performance large-area aesthetic BIPV modules, and represent a big step forward toward the fabrication of solar cells with high efficiency and high transparency.

Microwave Land Surface Emissivity (MLSE) over China under both clear and cloudy sky conditions was retrieved using measurements of recalibrated microwave brightness temperatures (Tbs) from Fengyun-3B Microwave Radiation Imager (FY-3B MWRI), combined with cloud properties derived from Himawari-8 Advanced Himawari Imager (AHI) observations. The contributions from cloud particles and atmospheric gases to the upwelling Tbs at the top of atmosphere were calculated and removed in radiative transfer. The MLSEs at horizontal polarizations at 10.65, 18.7, and 36.5 GHz during 7 July 2015 to 30 June 2019 over China showed high values in the southeast vegetated area and low values in the northwest barren, or sparsely vegetated, area. The maximum values were found in the belt area of the Qinling-Taihang Mountains and the eastern edge of the Qinghai-Tibet Plateau, which is highly consistent with MLSEs derived from AMSR-E. It demonstrates that the measurements of FY-3B MWRI Tbs, including its calibration and validation, are reliable, and the retrieval algorithm developed in this study works well. Seasonal variations of MLSE in China are mainly driven by the combined effects of vegetation, rainfall, and snow cover. In tropical and southern forest regions, the seasonal variation of MLSE is small due to the enhancement from vegetation and the suppression from rainfall. In the boreal area, snow causes a significant decrease of MLSE at 36.5 GHz in winter. Meanwhile, the MLSE at lower frequencies experiences less suppression. In the desert region in Xinjiang, increases of MLSEs at all frequencies are observed with increasing snow cover.

The nanofabrication platform was carried out using an atomic force microscope (AFM) system and a continuous wave (cw) laser to investigate the influence of laser power on the underlying mechanism of nanostructures fabricated by multiphysics fields tip enhancement (MFTE) induced by a cw laser irradiating the AFM probe tip. The nanostructure fabrication of nanopits and grooves and nanodots and lines on a polymethyl methacrylate thin film was conducted in an ambient environment by changing the incident laser power. The dependence of the MFTE on laser power was numerically analyzed, too. The lateral dimensions of nanopits and grooves and nanodots and lines characterized in situ were 154 nm, 96 nm, 188 nm, and 25 nm, respectively, breaking the optical diffraction limit. It turned out that the nanostructures converted from craters (pits and grooves) to protrusions (dots and lines) when altered with the laser power. Different laser powers can trigger the MFTE to change, thus, inducing varied coupling energy, which is the essential mechanism for nanostructure conversion. We also established a model to analyze the nanostructures transition and to predict the dimensions of nanostructures. The simulation results demonstrate that the MFTE has an essential effect on the formation of nanostructures, which are in good agreement with the experimental results.

Physical activity (PA) goal adherence is consistently associated with greater weight loss during behavioral obesity treatment, and early weight loss response predicts future weight loss success. However, it remains unclear which behaviors during the initial weeks of treatment distinguish responders from nonresponders and might be effective targets for improving treatment outcomes. To characterize subgroups with distinct patterns of PA goal adherence during the initial 2 months of an online, group-based weight control program and determine associations between these patterns and 6-month weight loss. Participants received an online behavioral obesity intervention with PA goals and daily self-monitoring. Weekly adherence to step goals and moderate-to-vigorous PA (MVPA) minute goals based on self-monitoring records were examined using latent class analysis. Body weight was objectively measured at 0, 2, and 6 months. Participants (N= 212; 91.5% female, 31.6% race/ethnic minority, mean body mass index: 35.8 ± 5.9 kg/m2) clustered into three subgroups based on early goal attainment: “Both PA Goals,” “MVPA Goals Only,” and “Neither PA Goal.” The “Both PA Goals” class had significantly greater 6-month weight loss (estimated mean weight loss [95% CI]: −9.4% [7.4 to 11.5]) compared to the “MVPA Goals Only” (−4.8% [3.4 to 6.1]) and “Neither PA Goal” classes (−2.5% [1.4 to 3.6]). Individuals meeting both PA goals early in treatment achieve greater weight losses than those meeting MVPA but not step goals, pointing to the need to explore factors associated with nonadherence to each of the PA goals to better understand these potential targets for treatment refinement and adaptive interventions.This study is the first to characterize subgroups of individuals engaged in a behavioral weight control program with distinct patterns of early physical activity (PA) goal attainment. These early PA patterns emerged as a novel factor associated with subsequent weight loss and provide an important lens to view early treatment engagement. The greatest weight losses were seen in the subgroup likely to meet program goals for both weekly minutes of moderate-to-vigorous PA and daily steps. Understanding the factors associated with PA goal attainment during the initial 2 months of a behavioral weight control program may provide insights that will allow early identification of likely treatment success and detect individuals at risk for reduced weight losses, which could signal individuals for whom additional or different support may then be directed to increase weight loss success.This commentary provides an overview of how tailored physical activity intervention development may benefit from 1) improving the engagement of diverse knowledge users in co-design and 2) gaining a better understanding of the ethical considerations that may affect the use of technology to support tailored interventions.

Reducing the lateral scale of two-dimensional (2D) materials to one-dimensional (1D) has attracted substantial research interest not only to achieve competitive electronic applications but also for the exploration of fundamental physical properties. Controllable synthesis of high-quality 1D nanoribbons (NRs) is thus highly desirable and essential for further study. Here, we report the implementation of supervised machine learning (ML) for the chemical vapor deposition (CVD) synthesis of high-quality quasi-1D few-layered WTe2NRs. Feature importance analysis indicates that H2gas flow rate has a profound influence on the formation of WTe2, and the source ratio governs the sample morphology. Notably, the growth mechanism of 1T′ few-layered WTe2NRs is further proposed, which provides new insights for the growth of intriguing 2D and 1D tellurides and may inspire the growth strategies for other 1D nanostructures. Our findings suggest the effectiveness and capability of ML in guiding the synthesis of 1D nanostructures, opening up new opportunities for intelligent materials development.

In the coal mine transportation, the scraper conveyor chute is badly worn. However, the abrasion performance has not been well documented. In this study, the chute was wear tested under a single factor using a modified pin-on-disc apparatus, including normal load, sliding distance, bulk coal characteristics (water content, gangue content), and chute material. Experiments were also carried out with a simultaneous variation of these factors. Generally speaking, the influence of coal characteristics on the chute wear was obviously higher than that of normal load and sliding distance. An improved wear predict model was obtained taking the operational parameters and bulk coal characteristics into account. The wear mechanism involved micro-ploughing, corrosion, adhesion, and fatigue peeling.

SiCN thin film is one of the most attractive silicon-based materials due to its excellent electrical, mechanical and optical properties. In this study, SiCN thin films have been prepared by the radio frequency reactive magnetron sputtering method under different sputtering power, pressure, and substrate temperature. The microstructure, morphology, and the optical and field emission properties of SiCN thin films were performed. The results indicated that the high-quality SiCN thin films have been successfully prepared and it is proved that these properties can be tailored by the preparation conditions. A main near ultraviolet light emission line at around 370 nm in SiCN thin films makes it suitable for the development of optoelectronic devices. This study can provide novel guidance for the controlled preparation of high-quality SiCN thin films by magnetron sputtering.

The movement of the floating connecting mechanism between a hydraulic support and scraper conveyor is space movement; thus, when the hydraulic support pushes the scraper conveyor, there is an error between the actual distance of the scraper conveyor and the theoretical moving distance. As a result, the scraper conveyor cannot obtain the straightness requirement. Therefore, the movement law of the floating connecting mechanism between the hydraulic support and scraper conveyor is analyzed and programmed into the Unity3D to realize accurate pushing of the scraper conveyor via hydraulic support. The Coal Seam + Equipment Joint Virtual Straightening System is established, and a straightening method based on the motion law of a floating connection is proposed as the default method of the system. In addition, a straightening simulation of the scraper conveyor was performed on a complex coal seam floor, the results demonstrate that the average straightening error of the scraper conveyor is within 2–8 mm, and is in direct proportion to the fluctuation of the coal seam floor in the strike of the seam with high accuracy, the straightness of scraper conveyor is more affected by the subsidence terrain during straightening than by the bulge terrain. And some conclusions are verified by experiment. Based on the verification of the relevant conclusions, a comparison and analysis of Longwall Automation Steering Committee (LASC) straightening technology and default straightening method in the simulation system shows that the straightness accuracy of LASC straightening technology under complex floor conditions is slightly less than that of the default straightening method in the proposed system.

[Display omitted] • Homologous BiVO 4 and BBN are used for constructing BiVO 4 −BBN heterostructure. • All-solid-state Z-scheme prolongs the lifetime of photoexcited electrons and holes. • Hydrogen evolution is realized firstly in the BiVO 4 −BBN heterostructure. As a visible-light response photocatalyst, BiVO 4 is widely used in photocatalytic oxygen evolution. In this study, a novel BiVO 4 −Bi 6 O 6 (OH) 3 (NO 3) 3 (BBN) heterostructure fabricates via a simple one-pot hydrothermal approach is certified to effectively restrain the recombination of carriers by efficient spatial charge separation. By employing BBN as a reductive-function photocatalyst, a solid-state Z-scheme is constructed to improve the photo-redox capacity of BiVO 4 and hydrogen production is realized in the BiVO 4 −BBN heterostructure for the first time. The solid-state Z-scheme introduced in the BiVO 4 −BBN ensures the photoexcited carriers with the powerful redox capacity to participate in the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Vanadium dioxide (VO2) is a strongly correlated electronic material and has attracted significant attention due to its metal-to-insulator transition and diverse smart applications. Traditional synthesis of VO2usually requires minutes or hours of global heating and low oxygen partial pressure to achieve thermodynamic control of the valence state. Further patterning of VO2through a series of lithography and etching processes may inevitably change its surface valence, which poses a great challenge for the assembly of micro- and nanoscale VO2-based heterojunction devices. Herein, we report an ultrafast method to simultaneously synthesize and pattern VO2on the time scale of seconds under ambient conditions through laser direct writing on a V5S8“canvas”. The successful ambient synthesis of VO2is attributed to the ultrafast local heating and cooling process, resulting in controlled freezing of the intermediate oxidation phase during the relatively long kinetic reaction. A Mott memristor based on a V5S8–VO2–V5S8lateral heterostructure can be fabricated and integrated with a MoS2channel, delivering a transistor with abrupt switching transfer characteristics. The other device with a VSxOychannel exhibits a large negative temperature coefficient of approximately 4.5%/K, which is highly desirable for microbolometers. The proposed approach enables fast and efficient integration of VO2-based heterojunction devices and is applicable to other intriguing intermediate phases of oxides.

To investigate the wear characteristics and mechanisms of the scraper and groove side friction pair under various factors, this study utilizes the scraper conveyor SGZ1000/2 × 1200 as the prototype and designs a test bench with a similarity ratio of 1:6. The Plackett–Burman experiment is used to examine the significant effects of five key factors (running speed, normal load, particle size, gangue content, and groove side clearance) on the groove side wear. It reveals that gangue content exerts the most significant impact, while the normal load is relatively minor. The interaction between factors is studied through the Box–Behnken experimental design. By analyzing the interaction through the obtained second-order regression model, it can be concluded that the interaction between running speed and groove side clearance, as well as the interaction between running speed and particle size, exacerbates groove side wear. The significant factors are validated through single-factor experiments. To further analyze the variations in wear under each factor, the changes from the second to the fourth level of each single factor are selected and compared with other factors. The running speed increasing from 0.06 m/s to 0.12 m/s results in a 102.67% wear amount increase. A 95.21% increase occurs when the particle size increases from 1.5 mm to 2.5 mm. Gangue content exhibits the most significant impact, where the content increases from 8% to 25%, marking a 205.73% rise. The wear morphology shifts from shallow pits and furrows to deeper ones, accompanied by a noticeable increase in quantity. Conversely, the wear amount and morphology changes least in groove side clearance, when the groove side clearance increases from 0 mm to +1 mm, a decline of 63.47%. The morphology shifts from numerous deep pits and furrows to shallower and smaller ones, indicating the mildest abrasive wear phenomenon.

The postpartum period is a unique time when sleep deficiency often occurs. Black and White adults are reported to have differences in sleep characteristics, but little is known if these differences exist in the postpartum period. Therefore, the purpose of this study was to examine sleep characteristics in a cohort of Black and White women from 6-8 weeks to 12 months postpartum.

Three-body wear is the primary wear mechanism in friction pair between groove side and scraper. This study quantitatively investigates the effect of groove textures on three-body wear under different factor combinations through abrasive wear experiments. The results indicate that groove textures significantly reduce wear of samples. The wear reduction rate of sample reaches 41% under the optimal factor combination. Width, depth, and tilt angle of groove textures significantly influence wear loss. Among these factors, width exhibits a negative effect on the change of wear loss, while depth and tilt angle show positive effects. Additionally, there are interactive effects on the change of wear loss between width and depth, as well as width and tilt angle. The effect process of groove textures to three-body wear was qualitatively analyzed by discrete element method (DEM) simulation. Combined with wear morphologies, the wear-resistant mechanism of groove textures was explored. The results indicate that groove textures can mitigate the severity of three-body abrasive wear, reduce the contact area between particles and samples, alter particles movement and enhance wear resistance. Meanwhile, groove textures can serve as a guiding mechanism to modify particles movement and direction and transform the sliding motion of coal particles into rolling motion, converting the continuous “face-face” contact of three-body wear into intermittent “point-face” and “line-face” contacts. This study provides novel study ideas and theoretical foundations for wear-resistant designs in mining machinery and three-body wear equipment.

The relationship between local epicardial adipose tissue (EAT) macrophages and atrial fibrillation (AF) remains unclear. The purpose of this study was to investigate the role of KCa3.1 in the migration of macrophages from EAT to adjacent atrial tissue during rapid pacing.

Blister beetles of Epicauta impressicornishave attracted attention because they contain a large amount of cantharidin (CTD). To date, however, the synthesis and transfer of CTD in adults of E. impressicornisare largely unknown. Here, we showed that the larvae E. impressicornisare capable of synthesizing CTD and they consume CTD during pupation. Before sexual maturity, both male and female adults synthesized a small amount of CTD, while after sexual maturity, males produced larger amounts of CTD, but females did not. The newly synthesized CTD in males first appeared in the hemolymph and then accumulated in the reproductive system. During the mating, the males transferred CTD to the reproductive system of females. In addition, a farnesyl pyrophosphate synthase (FPPS) gene was identified in male E. impressicornis. RNA-seq analysis, quantitative RT-PCR, and RNA interference analyses were conducted to investigate expression patterns and the functional roles of E. impressicornisFPPS (EiFPPS). Our results indicate that EiFPPSis highly expressed in the fat body of males. Moreover, the knock-down of EiFPPSled to a significant decrease in CTD synthesis. The current study indicates that EiFPPSis expressed in the fat body to regulate CTD synthesis in male E. impressicornisblister beetles.

This study aims to explore how different chain speeds and loads impact the fatigue life of the scraper conveyor chain ring. To achieve this, the study validates the reliability of a coupled simulation involving multi-body dynamics and the discrete element method. It also acquires time-varying tension load spectra under various operational conditions. The research evaluates the effects of distinct chain speeds and loads on parameters such as chain tension, vibration acceleration in the Y and Z-directions of the chain ring. Furthermore, finite element simulation is employed to examine stress distribution changes and fatigue life trends within the three-chain ring structure. The findings demonstrate that Y and Z-direction vibration accelerations of the chain ring correlate positively with the load. Additionally, the vibration acceleration in the Y-direction correlates positively with the chain speed. Across different chain speeds and loads, the maximum equivalent stress in the chain ring exhibits dynamic variations mirroring the load spectrum. Within the elastic deformation range of the chain ring, the highest stress within the transition region correlates linearly with chain tension. Load has a greater effect on the fatigue life of chain rings than chain speed. The fatigue life within the transition region of the chain ring decreases exponentially with increasing load at a constant chain speed. Conversely, at a constant load, chain ring life correlates positively with chain speed. Specifically, the fatigue life of the chain ring in LS 22 amounts to 32.64 days. When both chain speed and load are adjusted by 25%, the chain ring's lifespan reduces by 51.66% during simultaneous increments and increases by 39.26% with concurrent reductions in speed and load.

Filamentous fungi frequently degenerate during subculturing, which manifests as the reduction or loss of conidiation, sexuality, secondary metabolite production, and/or virulence against hosts. The underlying mechanism of spontaneous fungal degeneration is still elusive. In this study, the fluffy mycelium-type sector variants formed by three ascomycete fungi were transferred and found to show the typical features of culture degeneration. The variant cells were evidenced with the accumulation of reactive oxygen species (ROS), and the ROS-associated formation of hyphal coils. Genome resequencing of these sector cultures identified substantial random mutation sites in each variant in a trend associated with fungal reproduction style. The high bias towards transversions over transitions was similarly detected in degenerate genomes. Otherwise, a higher number of mutations were accumulated in the intergenic regions of the Metarhizium robertsiiand Cordyceps militarissector genomes, whereas the exonic regions of the Aspergillus nidulansvariant genes were detected with a higher mutation rate. Unexpectedly, none of those mutated genes had orthologous relationships among the three sectors, while only a few of them were shared between two fungi. A few transcription factor genes with frameshift mutations in sectors were selected for deletions in parental strains, and the null mutants demonstrated the varied degrees of degenerate phenotypes. In addition to reasoning the causal mechanism of fungal degeneration, our data provide insights to better maintain and monitor fungal culture stability.

The fabrication of nanostructures beyond the diffraction limit has been the focus of nanotechnology research. Scanning probe microscopy (SPM) has attracted the attention of researchers for the detection and manufacture of nanostructures. Here, a nanosecond laser irradiated a cantilevered scanning near-field optical microscopy (SNOM) tip and directly wrote subwavelength nanostructures on Au nanofilm, without the assistance of a mask or vacuum atmosphere. This method was stable and reproducible for long-term use. The in situmorphology detection was conducted after the writing process by atomic force microscope (AFM). A feature linewidth of approximately 83.6 nm (<λ/6) was confirmed using scanning electron microscopy (SEM). Linewidth of 167.8 ± 6.6 nm was reproduced stably. Theoretical calculations revealed that the elliptical heat distribution under the SNOM tip generated different linewidths when the tip scanned vertically and horizontally. It also interpreted the influential mechanism of single-pulse energy. The simulated linewidths were consistent with the fabricated linewidths. According to the elemental analysis by energy dispersive spectrometer (EDS), the mechanism of this method can be interpreted as melting of the Au nanofilm instead of oxidation. Owing to its high positioning, machining accuracy, and instantaneous energy, this technology is considered convenient and economical for nanostructure fabrication and is proposed to be applied in nanolithography on multiple materials in the future.

Due to the complex mining environment, the development of equipment intelligence has stagnated, with challenges in the application of key technologies. Additionally, underground inspectors exhibit a lower level of intelligence in monitoring, decision-making, and control aspects. This paper proposes an MMI-HCPS (Multiple Mine Inspectors- Human-Cyber-Physical System) method that integrates the perception, decision, and control capabilities of multiple mine inspectors. Firstly, it reviews the current status of equipment intelligentization in fully mechanized mining faces to highlight the necessity of equipment intelligentization. Secondly, the paper establishes the theoretical framework MMI-HCPS and further refines the overall structure of the entire document based on MMI-HCPS, composed of high-performance multi-site and multi-device communication network (MCN), intelligent inference system (IIS), inspection-human-system (IHS), and center-human-system (CHS). MCN forms the foundation for the overall architecture to operate smoothly, while IIS, IHS, and CHS constitute the core components driving the operation of MMI-HCPS. Both IIS and CHS have their own monitoring and control subsystems, and their decision subsystems are in a loop with IIS, achieving closed-loop inference. Finally, a utilizing the laboratory environment, separate tests were conducted on the network operation status of MCN, monitoring and control capabilities of IHS and CHS, experimental validation of decision-making abilities of multiple inspectors, and ultimately, an experiment was undertaken to assess the overall inspection process. The results indicate that promoting the intelligence of inspectors in the fully mechanized mining face from an intelligent perspective is feasible with this method. The method achieves a shared perception of the fully mechanized mining face among different inspectors, complementing each other’s strengths and weaknesses, enhancing information processing efficiency, and improving individual work efficiency. Furthermore, the method enables an interactive loop between human, computers, and the physical mining face, providing support for further intelligent development of mining equipment.