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Flexible pressure sensors have attracted a lot of attention in fields such as medicine and healthcare due to their ease of making wearable devices. However, the development of flexible pressure sensors is facing the challenges of a complex manufacturing process and high cost. Herein, a zinc oxide (ZnO) piezoelectric film flexible pressure sensor with a 3 × 3 sensor array presented through an extremely simple and ultralow‐cost fabrication process is reported. The 3 × 3 sensor array in series and again, in parallel. The output voltage of the 3 × 3 sensor array is significantly higher compared to the original thin‐film piezoelectric sensors at the same film thickness. The ZnO flexible pressure sensor shows good linear sensitivity and high durability over 4000 cycles of loading in the test range of 0–14 N. The response and recovery times tend to decrease as the dynamic pressure increases in the experimental range. Furthermore, a high‐precision dynamic force calibration system through a comparison between the open‐loop and closed‐loop strategies used in the dynamic force calibration experiments that are performed is presented. Potential applications of the sensor are demonstrated, including elbow flexure and finger tapping. The sensor also shows the ease of massive fabrication. [ABSTRACT FROM AUTHOR]

During the titanium alloy milling process, high temperatures in the tool-chip contact area will affect the tool life and precision of titanium alloy machining. Therefore, it is essential to measure the temperature of the tool-chip contact area continuously. In this paper, a finite element simulation model of the milling process was established using ABAQUS2020 to obtain the highest temperature location in the tool-chip contact area when milling titanium alloy. The integration of the wire with the alumina ceramic substrate formed an integrated wire substrate. Furthermore, NiCr, NiSi, and SiO2 films were deposited on the substrate sequentially using the DC pulsed magnetron sputtering technique. Finally, its microscopic morphology and static and dynamic performance were tested. The results show that the developed thin-film thermocouple temperature sensor has a Seebeck coefficient of 40.72 μV/°C and a dynamic response time of 0.703 ms. The application of the sensor to our titanium alloy milling experiments showed that the sensor can monitor the transient temperature in the tool-chip contact area, and its temperature measurement performance showed no detrimental effect from wearing. The effect of each milling parameter on the milling temperature was analyzed using ANOVA, and a regression model with an R-sq of 96.76% was obtained for the milling temperature. [ABSTRACT FROM AUTHOR]

Aero-engine turbine stator blades are often used in harsh environments with high temperatures and high pressure and are prone to fatigue fractures. Real-time and accurate monitoring of blade surface stress and strain is critical to ensure safe operation. In this study, thin-film strain gauges (TFSGs) that can be used in high-temperature environments above 1000 °C were designed and fabricated using a PtRh6 thin film as the sensitive material. The hysteresis effect of the stress transfer upon establishing a thermo-mechanical coupling finite element model of the Inconel718 high-temperature nickel-based alloy equal-strength beam PtRh6 TFSGs was analyzed and the optimal combination of thin-film thickness and longitudinal grid length of wire-grid TFSGs was determined. In order to solve the problem of high-temperature insulation, the insulating properties of a single-layer Al2O3 insulating film, a single-layer ZrO2 insulating film, a double-layer Al2O3/ZrO2 composite insulating film, and a four-layer Al2O3/ZrO2/Al2O3/ZrO2 composite insulating film at high temperature were compared and studied using scanning electron microscopy to analyze the microscopic morphology and composition of the four insulating film structures. The results showed that the four-layer Al2O3/ZrO2/Al2O3/ZrO2 composite insulating film had the best insulating properties at high temperatures. On this basis, an Al2O3/ZrO2/Al2O3/ZrO2 composite insulating film, PtRh6 sensitive layer, and Al2O3 protective film were sequentially deposited on a high-temperature nickel-based alloy equal-strength beam using DC pulsed magnetron sputtering technology to obtain an Inconel718 high-temperature nickel-based alloy equal-strength beam PtRh6 TFSG. Its gauge factor (GF) and temperature coefficient of resistance (TCR) were calibrated, and the results showed that the sensor could be used in harsh environments of 1000 °C. The above results provide new ideas for measuring stress and strain in aerospace under high-temperature and high-pressure environments. [ABSTRACT FROM AUTHOR]

The research on the thermal characteristics of railway double-row tapered roller bearing is of great significance for its structural design and operation monitoring. We established the quasi-static mechanical model of the bearing according to the test conditions, and we obtained the load distribution and kinematic parameters of the bearing. We studied the temperature distribution of railway double-row tapered roller bearing under test conditions through finite element analysis, which was consistent with the test results. We built a bearing testbed to study the effects of different rotating speeds on the temperature distribution of the bearing inner ring, outer ring, and roller. The results show that the speed dramatically affects the bearing inner ring. With the rate increase, the temperature difference between the inner and outer rings decreases gradually, and the temperature at the large end of the roller is the highest. [ABSTRACT FROM AUTHOR]

With the continuous improvement of train speeds, it is necessary to find the possible problems of bearings in time, otherwise they will cause serious consequences. Aiming at the characteristics of rapid temperature change of bearings, a thin film thermocouple temperature sensor was developed to measure the real-time temperature of the bearing's rolling elements during train operation. Using dc pulse magnetron sputtering technology, Al2O3 film, NiCr film, NiSi film, and SiO2 film were successively deposited on an aluminum alloy substrate. We studied their microstructure, static characteristics, dynamic characteristics, and repeatability. Finally, we installed an adaptive film temperature sensor on the bearing testing machine to measure the temperature of the rolling elements. The results show that the developed temperature sensor has good linearity in the range of 30~180 ℃. The Seebeck coefficient is 40.69 μV/℃, the nonlinear fitting error is less than 0.29%, the maximum repeatability error is less than 4.55%, and the dynamic response time is 1.42 μs. The temperature of the measured rolling elements is 6~10 ℃ higher than that of the outer ring, which can reflect the actual temperature of the bearing operation. [ABSTRACT FROM AUTHOR]

ZnO film is widely used in the field of health monitoring sensors, which has high requirements for the piezoelectric coefficient and film-to-substrate adhesion of the ZnO film. In this study, ZnO thin films were grown on a GH4169 superalloy steel (GSS) substrate using magnetron sputtering, and the effects of the sputtering power, argon–oxygen ratio, and sputtering pressure on the piezoelectric coefficient and film-to-substrate adhesion were studied. The composition, microstructure, and crystal orientation of ZnO thin films deposited under different process parameters were analyzed using X-ray diffraction (XRD), a scanning electron microscope (SEM), and an energy spectrum analyzer (EDS). The piezoelectric coefficient d33 was measured using a piezoelectric coefficient measuring instrument. The critical value of adhesion between the film and substrate was measured using the scratch method. The results demonstrated that the ZnO films had the most desirable properties when the sputtering power was 150 W, the argon–oxygen ratio was 25:10, and the sputtering pressure was 0.7 Pa. The XRD results showed that the ZnO film samples had the strongest (002) crystal orientation at 2θ = 34.4°; the SEM photos showed that the film samples were flat and uniform; and the EDS composition analysis results showed that the composition was close to the theoretical value. The maximum d33 coefficient value was 5.12 pC/N, and the maximum value of film-to-substrate adhesion between the ZnO films and GSS substrate was 4220 mN. [ABSTRACT FROM AUTHOR]

At present, piezoelectric sensors are primarily applied in health monitoring areas. They may fall off owing to the adhesive's durability, and even damage the monitored equipment. In this paper, a piezoelectric film sensor (PFS) based on a positive piezoelectric effect (PPE) is presented and a ZnO film is deposited on a GH4169 superalloy steel (GSS) substrate using magnetron sputtering. The microstructure and micrograph of ZnO piezoelectric thin films were analyzed by an X-ray diffractometer (XRD), energy dispersive spectrometer (EDS), scanning electron microscope (SEM), and atomic force microscope (AFM). The results showed that the surface morphology was dense and uniform and had a good c-axis-preferred orientation. According to the test results of five piezoelectric sensors, the average value of the longitudinal piezoelectric coefficient was 1.36 pC/N, and the average value of the static calibration sensitivity was 19.77 mV/N. We selected the sensor whose parameters are closest to the average value for the dynamic test experiment and we drew the output voltage response curve of the piezoelectric film sensor under different loads. The measurement error was 4.03% when repeating the experiment six times. The research achievements reveal the excellent performance of the piezoelectric film sensor directly deposited on a GH4169 superalloy steel substrate. This method can reduce measurement error caused by the adhesive and reduce the risk of falling off caused by the aging of the adhesive, which provides a basis for the research of smart bolts and guarantees a better application in structural health monitoring (SHM). [ABSTRACT FROM AUTHOR]

Plasmon Ag and co-catalyst CoxP decorated mesoporous graphite carbon nitride nanosheet assemblies have been synthesized via a template-calcination and ball milling strategy combined with photoreduction. The obtained composites are characterized by x-ray diffraction, Fourier transmission infrared spectroscopy, x-ray photoelectron spectroscopy, transmission electron microscopy, and UV–vis diffuse reflectance spectroscopy. The results show that the sample assembly with mesoporous structure has specific surface area of 50.4 m2 g−1, pore size of 11.3 nm and pore volume of 0.21 cm3 g−1. The Ag and CoxP nanoparticles are decorated on the surface of graphite carbon nitride uniformly. Under solar light irradiation, the photocatalytic degradation rate of ceftazidime for the prepared sample assembly is up to ∼92%, and the photocatalytic reaction rate constant is about 10 times higher than that of bare graphite carbon nitride. Moreover, the sample assembly also exhibits a solar-driven photocatalytic hydrogen production rate of 96.66 μmol g−1 h−1. It can attributed to the surface plasmon resonance effect of Ag nanoparticles and CoxP co-catalyst promoting the spatial charge separation and the mesoporous structure providing more surface active sites and favoring mass transfer. This special structure offers new insights for fabricating other high-performance photocatalysts with high spatial charge separation [ABSTRACT FROM AUTHOR]

Delamination factor is one of the most important factors evaluating the surface integrity of carbon fiber–reinforced polymer laminates. The value of the delamination factor in edge trimming of carbon fiber–reinforced polymer laminates controlled the acceptance or rejection of the machined component. Therefore, using a reasonable and efficient approach to characterize the delamination region is very beneficial. However, the conventional delamination factor is a one-dimensional evaluation method, and hence, it cannot distinguish the delamination extent of carbon fiber–reinforced polymer laminates after edge trimming. The contribution of this work is to present a novel assessment approach to characterize the cutting-induced delamination using a milling cutter and compare it with the conventional delamination factor. The experimental results indicated that the delamination factor based on area assessment method is suitable to evaluate the delamination extent at the top layer after edge trimming. [ABSTRACT FROM AUTHOR]

Herein, C,N co-doped porous TiO2 hollow sphere visible light photocatalysts were fabricated using biocompatible N-lauroyl-l-glutamic acid as a doped precursor and soft-template by a mild and facile self-assembly soft-template method, followed by calcination at 550 °C in air. The structure, morphology, and surface elemental composition were characterized in detail by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results show that the prepared TiO2 photocatalysts have a porous hollow sphere structure and are co-doped with C and N. The visible-light-driven photocatalytic degradation rates of phenol and 2-chlorophenol are ∼92 and 90%, respectively. The photocatalytic reaction rate constants of phenol and dichlorophen on HPT550 porous TiO2 hollow spheres were about ∼4 and ∼2 times higher than those on P25, respectively. This enhancement is because the C,N co-doped porous TiO2 hollow spheres not only extend the photoresponse to the visible light region as C,N co-doping narrows the bandgap (2.7 eV), but also expose a large number of surface active sites that favor visible-light-driven photocatalysis. Moreover, the porous hollow structure favors multiple reflections of photons in the interior, increasing the utilization ratio of light. It is worth to pay more efforts to the development of visible light photocatalysts and further promote their practical application. [ABSTRACT FROM AUTHOR]

Brucellosis is a common zoonotic infection worldwide and a major public health problem in developing countries including China. The aim of our study was to investigate the seroprevalence of Brucella infection in humans in Yixing, located at the centre of the Yangtze River Delta Urban Agglomeration. A total of 895 sera from apparently healthy abattoir workers and 3303 sera from general healthy people living in rural areas were collected in Yixing, screened by Rose-Bengal plate agglutination test (RBPT) and the positives were confirmed by standard tube agglutination test (SAT) according to official Chinese diagnostic criteria. Seropositivity among abattoir workers was 16.42% compared to zero among the general population living in rural areas. No significant difference of seropositivity was observed in age groups. Contact or inhalation of Brucella organisms from infected animals, principally goats, was found to be a significant risk factor. Education in occupational hygiene and public healthcare programmes are needed to control this emerging problem. [ABSTRACT FROM AUTHOR]

In the present work, the oxidized corn starch was prepared by using chlorine dioxide as novel oxidant. It was characterized by X-ray diffraction, scanning electron microscope (SEM), and transmission electron microscope (TEM). The main factors that affect the oxidation process were studied, and the oxidation degree of oxidized starch was determined by the carboxyl content and viscosity of the product. The results show that carboxyl groups are introduced into the starch chains successfully, and the oxidation reaction mainly carries out at the amorphous area. Compared with native starch, the light transmittance and anti-retrogradation of oxidized starch increase, whereas the viscosity reduces. The best oxidized starch can be obtained at the sodium chlorate dosage of 3%, hydrochloric acid 4%, and sulfuric acid 3% (all based on the initial starch weight), while the oxidation reaction is conducted at 50°C for 5 h. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Ag-TiO 2−x (B)/g-C 3 N 4 ternary heterojunctions photocatalysts are fabricated by hydrothermal-calcination, photo-deposition procedure, and followed by in-situ solid-state chemical reduction procedure. As-obtained photocatalysts are consisted with heterojunctions between 2D g-C 3 N 4 sheets and 1D TiO 2 (B) single-crystalline nanorods. The band gap of Ag-TiO 2−x (B)/g-C 3 N 4 ternary heterojunctions photocatalysts is reduced to ∼2.23 eV due to plasma Ag and surface engineering. Under visible light irradiation, it has an optimal photocatalytic property for the reduction of Cr6+ (95%) and degradation of NH 4 + (93%). The apparent reaction rate constants (k) of ternary heterojunctions photocatalysts for NH 4 + and Cr6+ are 25 and 12 folds higher than that of original TiO 2 (B). Furthermore, Ag-TiO 2−x (B)/g-C 3 N 4 also has excellent hydrogen production efficiency, which is up to 410 µmol h−1 g−1. This enhancement can be attributed to the unique heterojunction formed by 1D single-crystalline TiO 2 (B) nanorods and 2D g-C 3 N 4 sheets, surface plasma resonance effect of plasma Ag nanoparticle, and surface engineering. A possible photocatalytic mechanism is also proposed by analysizing the XPS valence-band spectra and the Mott-Schottky. [ABSTRACT FROM AUTHOR]

Graphical abstract Ti3+ dual-doping single-crystalline SrTiO 3−x /TiO 2−x (B) heterojunction photocatalysts are fabricated via two-step hydrothermal process, followed by in-situ solid-state chemical reduction, and exhibit high visible-light-driven photocatalytic performance, which is ascribed to synergistic effect of the special nanoarchitecture, heterojunctions, oxygen vacancy and Ti3+ dual-doping favoring visible light absorption and spatial separation of photogenerated charge carriers. Abstract Ti3+ self-doped single-crystalline SrTiO 3−x nanocubes acting as molecular bricks are successfully assembled onto Ti3+ self-doping single-crystalline TiO 2−x (B) nanorods through an effortless two-step hydrothermal process coupled with an in situ solid-state chemical reduction method. SrTiO 3−x nanocubes act as molecular bricks, which are uniformly assembled onto the surface of TiO 2−x (B) nanorods due to lattice matching. The band gap of the resultant SrTiO 3−x /TiO 2−x (B) sample is ∼2.97 eV, which exhibits excellent photocatalytic performance for the reduction of Cr(VI) and hydrogen production under visible light. The apparent rate constant k value for the photocatalytic reaction of SrTiO 3−x /TiO 2−x (B) for Cr(VI) reduction is ∼8 times higher than that of white TiO 2 (B). The photocatalytic hydrogen production rate for SrTiO 3−x /TiO 2−x (B) is ∼160.2 μmol g−1 h−1, which is ∼5 times higher than that of white TiO 2 (B). The enhanced photocatalytic activity can be considered to be caused by a synergetic effect of heterojunction formation and the introduction of Ti3+ self-doping, which can not only facilitate the separation of photogenerated charge carriers between TiO 2−x (B) and SrTiO 3−x , but also broaden the photoresponse from the UV to visible-light region. [ABSTRACT FROM AUTHOR]

Mesoporous g-C 3 N 4 /Zn–Ti layered double hydroxide (LDH)-laminated van der Waals heterojunction nanosheets were prepared by a facile one-step in situ hydrothermal method. Due to the strong electrostatic interactions between the positively charged Zn–Ti LDH and negatively charged g-C 3 N 4 nanocrystal, a laminated van der Waals heterostructure was successfully formed between Zn–Ti LDH and g-C 3 N 4. The mesoporous g-C 3 N 4 /Zn–Ti LDH-laminated van der Waals heterojunction, which had a narrow bandgap of 2.41 eV extended the photoresponse to the visible light region. The obtained heterojunctions showed excellent visible-light-driven photocatalytic performance for the complete removal of ceftriaxone sodium (up to ∼97%) and a high hydrogen production rate (∼161.87 μmol h−1 g−1). This was mainly attributed to the formation of the laminated van der Waals heterojunctions, which favoured charge separation and the absorption of visible light, and the mesoporous structure, which provided more surface active sites. This facile strategy for preparing mesoporous g-C 3 N 4 /Zn–Ti LDH-laminated van der Waals heterojunctions offers new insights for the fabrication of high-performance van der Waals heterojunction photocatalytic materials. Mesoporous g-C 3 N 4 /Zn–Ti LDH Laminated Van der Waals Heterojunctions Nanosheets Photocatalysts are successfully prepared by in-situ hydrothermal method, due to the strong electrostatic interaction between positively charged Zn–Ti LDH and negatively charged g-C 3 N 4 nanocrystals, which shows excellent visible-light-driven photocatalytic performance because of the van der Waals heterojunctions favoring spatial charge separation. Image 1 • Mesoporous g-C 3 N 4 /Zn–Ti LDH van der Waals heterojunctions nanosheets are prepared. • It extends the photoresponse to visible light region. • It exhibits excellent visible-light-driven photocatalytic performance. • It is due to the van der Waals heterojunctions favoring spatial charge separation. [ABSTRACT FROM AUTHOR]

Plasmon Ag decorated 3D urchinlike N-TiO 2−x photocatalysts are successfully synthesized by a facile hydrothermal treatment (180 °C) and combined with a photo-deposition approach, followed by a reduction treatment. The results show that the resultant Ag/N-TiO 2−x sample possesses a three-dimensional (3D) urchinlike nanostructure with high crystallinity of anatase. Meanwhile, it exhibits the narrow optical band gap (Eg ∼ 2.61 eV) and the excellent visible-light-driven photocatalytic performance. Moreover, the hydrogen generation rate and photocatalytic degradation rate of phenol are up to 186.2 μmol h −1  g −1 and 97.7% under visible light irradiation, which are about 4.2 and 5.4 folds greater than that of N-TiO 2 . The mechanism of photocatalytic process is also proposed, and the enhanced photocatalytic property is mainly due to the synergistic reaction of the Ti 3+ and N codoping, which narrows the band gap and favors the utilization of visible light, and the plasmon effect of Ag nanoparticles and unique 3D urchinlike architecture, which are propitious to the separation and transmission of photogenerated carriers. [ABSTRACT FROM AUTHOR]

With the development of intelligent manufacturing technology, robots have become more widespread in the field of milling processing. When milling difficult-to-machine alloy materials, the localized high temperature and large temperature gradient at the front face of the tool lead to shortened tool life and poor machining quality. The existing temperature field reconstruction methods have many assumptions, large arithmetic volume and long solution time. In this paper, an inverse heat conduction problem solution model based on Gated Convolutional Recurrent Neural Network (CNN-GRU) is proposed for reconstructing the temperature field of the tool during milling. In order to ensure the speed and accuracy of the reconstruction, we propose to utilize the inverse heat conduction problem solution model constructed by knowledge distillation (KD) and compression acceleration, which achieves a significant reduction of the training time with a small loss of optimality and ensures the accuracy and efficiency of the prediction model. With different levels of random noise added to the model input data, CNN-GRU + KD is noise-resistant and still shows good robustness and stability under noisy data. The temperature field reconstruction of the milling tool is carried out for three different working conditions, and the curve fitting excellence under the three conditions is 0.97 at the highest, and the root mean square error is 1.43°C at the minimum, respectively, and the experimental results show that the model is feasible and effective in carrying out the temperature field reconstruction of the milling tool and is of great significance in improving the accuracy of the milling machining robot., Competing Interests: ZS was employed by Angang Heavy Machinery Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ma, Wang, E, Sha, Wang, Cui and Yin.)

Plasmon Ag and co-catalyst Co x P decorated mesoporous graphite carbon nitride nanosheet assemblies have been synthesized via a template-calcination and ball milling strategy combined with photoreduction. The obtained composites are characterized by x-ray diffraction, Fourier transmission infrared spectroscopy, x-ray photoelectron spectroscopy, transmission electron microscopy, and UV-vis diffuse reflectance spectroscopy. The results show that the sample assembly with mesoporous structure has specific surface area of 50.4 m 2 g -1 , pore size of 11.3 nm and pore volume of 0.21 cm 3 g -1 . The Ag and Co x P nanoparticles are decorated on the surface of graphite carbon nitride uniformly. Under solar light irradiation, the photocatalytic degradation rate of ceftazidime for the prepared sample assembly is up to ∼92%, and the photocatalytic reaction rate constant is about 10 times higher than that of bare graphite carbon nitride. Moreover, the sample assembly also exhibits a solar-driven photocatalytic hydrogen production rate of 96.66 μmol g -1 h -1 . It can attributed to the surface plasmon resonance effect of Ag nanoparticles and Co x P co-catalyst promoting the spatial charge separation and the mesoporous structure providing more surface active sites and favoring mass transfer. This special structure offers new insights for fabricating other high-performance photocatalysts with high spatial charge separation.

All-solid Z-scheme Bi-BiOCl/AgCl heterojunction microspheres are successfully prepared via hydrothermal, NaBH 4 reduction and chemical deposition strategy. They are tested by various characterization methods, and they show that metal Bi is present after reduction and AgCl nanoparticles are successfully compounded onto BiOCl. Bi plays the role of a bridge connecting the two semiconductors of BiOCl and AgCl. All-solid Z-scheme heterojunction structures are formed successfully. The narrow band gap of the Z-scheme Bi-BiOCl/AgCl heterojunction microspheres is about 2.17 eV, which can expand the optical response range. Moreover, the photocatalytic hydrogen production rate still reaches 198.2 μmol h -1 g -1 , extends the electron transport life, inhibits the recombination of electron hole pairs, and improves the photocatalytic activity.

Herein, C,N co-doped porous TiO2 hollow sphere visible light photocatalysts were fabricated using biocompatible N-lauroyl-l-glutamic acid as a doped precursor and soft-template by a mild and facile self-assembly soft-template method, followed by calcination at 550 °C in air. The structure, morphology, and surface elemental composition were characterized in detail by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results show that the prepared TiO2 photocatalysts have a porous hollow sphere structure and are co-doped with C and N. The visible-light-driven photocatalytic degradation rates of phenol and 2-chlorophenol are ∼92 and 90%, respectively. The photocatalytic reaction rate constants of phenol and dichlorophen on HPT550 porous TiO2 hollow spheres were about ∼4 and ∼2 times higher than those on P25, respectively. This enhancement is because the C,N co-doped porous TiO2 hollow spheres not only extend the photoresponse to the visible light region as C,N co-doping narrows the bandgap (2.7 eV), but also expose a large number of surface active sites that favor visible-light-driven photocatalysis. Moreover, the porous hollow structure favors multiple reflections of photons in the interior, increasing the utilization ratio of light. It is worth to pay more efforts to the development of visible light photocatalysts and further promote their practical application.