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The effect of high strain rate on adiabatic shear susceptibility and microstructures in Al0.4CoCrFeNi high-entropy alloy (HEA) was examined using a split Hopkinson pressure bar (SHPB) and hat-shaped specimens. The results exhibit a clear strain-hardening effect at high strain rates within the experimental range in six specimen groups. The adiabatic shear band (ASB) with an approximately 1 μm wide was formed at 1.05 × 105s−1due to thermoplastic instability resulting from adiabatic temperature rise. The central region of the ASB consists of ultrafine and equiaxed recrystallized grains with a typical size of 100 nm. Comparison of metallographic observation and calculation shear voltage-time, the dynamic shear stress-time curves and the dissipation energy, it was found that the adiabatic shear susceptibility of Al0.4CoCrFeNi HEA increases with increased strain rate. The thermodynamic and kinetic calculations indicate that dynamic recrystallization can occur in the shear band based on the rotational dynamic recrystallization (RDR) mechanism.

This study aimed to investigate the effect of oxidation temperature on the physical properties of β-Ga2O3grown by thermal oxidation of GaN in the O2ambient at high oxidation temperatures from 900 to 1400 °C. Notably, the analysis of the oxidation temperatures ranging from 1100 to 1400 °C remains unexplored in the other studies. The effects of the oxidation temperature on the physical properties were investigated via X-ray diffraction, X-ray photoelectron spectroscopy, and field-emission scanning electron microscopy (FESEM). At all oxidation temperatures, XPS results revealed oxygen deficiency. The top FESEM images indicated disordered nanocolumn structures on the surface of the oxide layer, which increased in abundance with oxidation temperatures exceeding 1100 °C. Energy-filtered high-resolution transmission electron microscopy images and the selected area electron diffraction patterns revealed that the top nanocolumns and the oxidized layer comprised polycrystalline β-Ga2O3. Additionally, the cross-sectional lamellae prepared through focused ion beam milling revealed an increase in the thickness of the β-Ga2O3 layer with oxidation temperature. To account for the variations in the oxide layer thickness, the oxidation temperatures were classified into two ranges of 900–1100 °C and 1100–1400 °C for calculating the activation energy. Moreover, this study assumed that the activation energy required for the oxidation process remained constant within each temperature interval. According to Arrhenius's model, the activation energy from 900 to 1100 °C was calculated to be 286.15 kJ/mol (2.97 eV). Furthermore, the activation energy from 1100 to 1400 °C was determined to be 111.33 kJ/mol (1.15 eV).

The microstructural evolution in adiabatic shear localization in Al0.4CoCrFeNi high-entropy alloy (HEA) was examined through a forced shear technique by a split Hopkinson pressure bar (SHPB) using hat-shaped specimens. The TEM results show that the elongated and parallel grains are the major characteristics of the transition region. The central region of the adiabatic shear band (ASB) is primarily composed of ultrafine and equiaxed recrystallized grains with sizes ranging from 50 to 250 nm, with a typical size of 100 nm. It is found that the plastic deformation of the majority of large grains (100–250 nm) is primarily mediated by dislocation slip. To effectively coordinate this deformation, twins with varying thicknesses were generated within the grains (50–100 nm) through cross-slip of dislocations and dynamic overlapping of four stacking faults (SFs) of dissociated dislocations, respectively. According to the classical one-dimensional Fourier heat conduction equation and recrystallization theory calculations, it is proved that ultrafine and equiaxed recrystallized grains did not undergo significant growth during the cooling stage after deformation. The thermodynamics and kinetics calculated results indicate that instant grain refinement within the ASB is due to the rotational dynamic recrystallization (RDR) that occurs during the deformation process.

The grain refinement mechanism in the adiabatic shear band (ASB) of solution treated Ti–10V–2Fe–3Al alloy was investigated under high strain rates using a split Hopkinson pressure bar and hat-shaped specimens. The TEM results show that elongated and parallel grains are the major characteristics of the transition region between the matrix and the centre of the ASB. The central region of the ASB consists of ultrafine and equiaxed recrystallized grains with a typical size of 100 nm. According to the classical one-dimensional Fourier heat conduction equation and recrystallization theory calculations, it is proved that ultrafine and equiaxed recrystallized grains did not undergo significant growth during the cooling stage after deformation. The thermodynamics and kinetics calculated results indicate that instant grain refinement within the ASB is due to the rotational dynamic recrystallization (RDR) that occurs during the deformation process.

A remarkable improvement in the conductivity of grown nitrogen-doped p-type β-Ga2O3films was successfully achieved via the thermal oxidation of GaN in N2O ambient at 1100 °C. In the vacuum test environment, its room temperature Hall hole concentration is 1.64 × 1017 cm−3, the Hall resistivity is 7.66 Ω cm, the Hall hole mobility is 4.98 cm2 V−1 s−1, and the acceptor ionization energy is 0.087 eV. In addition, the compositions and properties were also extensively investigated. When the oxidation temperature was raised from 900 to 1100 °C, the FWHM of the {2¯01}-oriented β-Ga2O3diffraction peak from the X-ray diffraction (XRD) pattern decreased to 0.237°, confirming an improvement in the crystalline quality of the β-Ga2O3nanocrystal structure. From both the cross-sectional view of the field emission scanning electron microscopy (FESEM) image and the cross-sectional lamellae prepared by focused ion beam (FIB) milling, it was observed that the generated β-Ga2O3film transformed into a two-layer morphology when oxidized at 1100 °C. The top layer is a rather loose film composed of nanorods, and the selected area electron diffraction (SAED) pattern of a nanorod confirmed it as high-quality (6¯03)-dominated monocrystal β-Ga2O3. The second layer is a comparatively compact β-Ga2O3film. This approach to the efficient growth of p-type β-Ga2O3can broaden the applicability of these two-layered structures. The randomly distributed monocrystal nanorods on the top layer are an appropriate candidate for the photocatalyst, while the relatively more compact second layer with high p-type conductivity can be employed in high-performance solar-blind UV photodetectors or high-power electronic devices.

Traffic flow prediction plays an important role in smart cities. Although many neural network models already existed that can predict traffic flow, in the face of complex spatio-temporal data, these models still have some shortcomings. Firstly, they although take into account local spatio-temporal relations, ignore global information, leading to inability to capture global trend. Secondly, most models although construct spatio-temporal graphs for convolution, ignore the dynamic characteristics of spatio-temporal graphs, leading to the inability to capture local fluctuation. Finally, the current popular models need to take a lot of training time to obtain better prediction results, resulting in higher computing cost. To this end, we propose a new model: Multi-Step Trend Aware Graph Neural Network (MSTAGNN), which considers the influence of global spatio-temporal information and captures the dynamic characteristics of spatio-temporal graph. It can not only accurately capture local fluctuation, but also extract global trend and dramatically reduce computing cost. The experimental results showed that our proposed model achieved optimal results compared to baseline. Among them, mean absolute error (MAE) was reduced by 6.25% and the total training time was reduced by 79% on the PEMSD8 dataset. The source codes are available at: https://github.com/Vitalitypi/MSTAGNN.

Over the past decade, the electric vehicle industry of China has developed rapidly, reaching one of the highest technological levels in the world. Nevertheless, most electric buses currently serve urban areas, being unsuitable for all-climate operations. In response to the objective of massively adopting electric vehicles for transportation during all the events of the 2022 Beijing Winter Olympics, a dual-motor coaxial propulsion system for all-climate electric vehicles is proposed. The system aims to meet operating requirements such as high speed and adaptability to mountainous roads under severely cold environments. The system provides three operating modes, whose characteristics are analyzed under different conditions. In addition, dual-motor collaborative control strategy with collaborative gearshift and collaborative power distribution is proposed to eliminate power interruption during gearshift process and achieve intelligent power distribution, thus improving the gearshift quality and reducing energy consumption. Finally, gear position calibration for all-climate operation and proper gearshift is introduced. Experimental results demonstrate the advantages of the proposed dual-motor coaxial propulsion system regarding gearshift compared with the conventional single-motor automatic transmission.

Lithium-ion batteries (LIBs) are commonly used in electric vehicles (EVs) due to their good performance, long lifecycle, and environmentally friendly merits. Heating LIBs at low temperatures before operation is vitally important to protect the battery from serious capacity degradation and safety hazards. This paper reviews recent progress on heating methods that can be used onboard. The existing methods are divided into two categories, namely external heating methods and internal heating methods, mechanisms, advantages and limitations of each method are systematically reviewed. Then, the rates of temperature rise, energy consumptions, and maximum temperature gradient of different methods are quantitatively summarized to compare the heating performances of each method. In addition, features related to the onboard application of each method are qualitatively compared, which is essential for the rapid cold start of EVs in frigid weather. Finally, prospects of external and internal heating methods are given. This paper aims to provide researchers and engineers with guidelines about how to select a method based on their requirements and application environments.

Besides fuel economy, gear shifting and engine start-stop frequency in the optimal energy management for hybrid electric vehicles (HEVs) will also influence the overall performance and drivability. However, such drivability concerns will also impact the vehicle’s energy efficiency. To solve this conflicting optimization problem, this paper aims to find the proper weighing of the conflicting costs to achieve a right balance based on sensitivity analysis. The problem is formulated by expanding the conventional cost function with additional penalty items for gear shifting and engine start-stop, and a range extended hybrid delivery truck is modeled as a case study. Dynamic programming (DP) algorithm is applied to guarantee all the comparisons are under the same benchmark, and a split-DP solution is carried out to accelerate the searching process. Analytical fitting and trend analysis methods are used to find the proper penalty factors. Eventually, a comprehensive comparison among optimized, experiential and none penalty factors is shown, indicating that such appropriate weighing can significantly improve drivability with only 0.2% more fuel cost.

A crystalline indium-gallium-oxide (InGaO) was used as the channel of a thin film transistor (TFT) with back-channel-etched (BCE) structure. The effects of deposition temperature (T) on crystal structure, morphology, electrical properties and corrosion resistance of InGaO films were studied in detail. X-ray diffraction spectra and scan electron microscopy reveal that the slight increase in corrosion resistance with T at 25-200degC results from the discrete crystallites embedded amorphous network while the massive increase at 290degC results from the high crystallinity of the film. The carrier concentration (Nc) and mobility of InGaO films show a huge increase as T increases due to the crystallization process at 25-200degC, but they change very little when the films are highly crystallized at 290degC. The BCE TFT exhibits a slightly higher saturated mobility of 11.9 cm2/(V*s), a more positive threshold voltage of [?]0.43 V, a larger subthreshold swing of 0.37 V/decade and a higher off-current of 4 pA when compared with the TFT fabricated by a lift-off process. Combined with X-Ray Photoelectron Spectroscopy analysis, the BCE process causes an oxygen-deficient back channel and introduces deep trap states, leading to the deterioration in electrical performance.

This letter investigates joint beamforming and antenna selection (JBAS) for a spatial diversity multiple-input multiple-output system, where the transmitter equipped with multiple antennas performs both antenna selection and beamforming optimization to maximize the received signal-to-noise ratio (SNR). The JBAS problem is NP-hard to solve due to a sparsity constraint. In this letter, we propose smooth approximation-based iterative algorithms to address the JBAS problem. The simulation results validate the effectiveness of the proposed algorithms in terms of the achieved SNR and the computational complexity.

Transcriptional plasticity interacts with natural selection in complex ways and is crucial for the survival of species under rapid climate change. How 3D genome architecture affects transcriptional plasticity and its interaction with genetic adaptation are unclear. We transplanted estuarine oysters to a new environment and found that genes located in active chromatin regions exhibited greater transcriptional plasticity, and changes in these regions were negatively correlated with selective signals. This indicates a trade-off between 3D active regions and selective signals in shaping plastic responses to a new environment. Specifically, a mutation, lincRNA, and changes in the accessibility of a distal enhancer potentially affect its interaction with the ManⅡagene, which regulates the muscle function and survival of oysters. Our findings reveal that 3D genome architecture compensates for the role of genetic adaptation in environmental response to new environments and provide insights into synergetic genetic and epigenetic interactions critical for fitness-related trait and survival in a model marine species.

The US Department of Energy (DOE) sponsored a study to determine the national savings achievable in the commercial buildings through widespread deployment of controls, elimination of faults, and use of better sensing. The study estimated savings from 34 measures in 9 building types and across 16 climates. These buildings are responsible for almost 57% of the US commercial building sector energy consumption. In addition to the individual measures, three packages of measures were created to estimate savings: (1) efficient building, (2) typical building, and (3) inefficient building. The results showed significant potential for energy savings across all building types and climates. The total site potential savings by building type aggregated across all climates for each measure varied between 0 and 16%. The total site potential savings aggregated across all building types and climates for each measure varied between 0 and 11%. The national potential site energy savings across all building types studied is 29%. Across all building types, the savings represent approximately 1393 PJ (1.32 quads) of site energy savings or 2912 PJ (2.76 quads) of primary (or source) energy savings. Extrapolating the results for other building types not analyzed as part of this study, the primary energy savings could be in the range of 4220 to 5275 PJ. For comparison, the total US primary energy consumption across all sectors of energy use was 102,762 PJ (97.4 quads) in 2015. This makes commercial building control improvements strategically important to sustained reductions in national energy consumption. To realize most of this potential savings, many gaps can be addressed through research development and deployment (RD&D), as recommended in this paper.

Constipation is a widespread gastrointestinal issue. This work aimed to investigate anti-constipation capacities of 9 novel strains of Lactobacillusand Bifidobacteriumusing in vitroexperiments for initial exploration and then further confirmed through in vivomodels including both zebrafish and mice. The in vitroexperimental results revealed that L. plantarumT34 and L. paracaseiYJ10 could survive under the simulated gastrointestinal tract conditions as standard strain L. rhamnosus(LGG) did. L. paracaseiYJ10 and L. caseiLc showed the highest 22 h's aggregation rate. L. rhamnosusW1 showed the highest coaggregation rate with E. coliand with S. aureus. T34 had the largest inhibition zones against S. typhimuriumand L. Monocytogenes.The highest adhesion rates with HT-29 cells were L. caseiLc, LGG and W1. Principal component analysis (PCA) and Fuzzy synthetic evaluation (FSE) were performed to evaluate the in vitroprobiotic potential of the 9 strains comprehensively. The order of scores on in vitroprobiotic property from high to low was as follows: T34, W1, YJ10, Lc, LGG, SLT, SS, Lb, YN4 and LQSQ. The subsequent in vivoexperiment of zebrafish further confirmed T34, W1 and YJ10 have better anti-constipation ability compared to other strains. Furthermore, T34 relieve loperamide-induced constipation by promoting gut transit in the mice model. In conclusion, T34 was demonstrated to prevent constipation and may be suggested for use in food and pharmaceutical goods.

Constipation is a common gastrointestinal problem. This study aimed to identify a combination of prebiotics and wheat peptides (WP) to promote intestinal peristalsis and explore the underlying mechanism. First, we screened four prebiotics (galacto-oligosaccharides (GOS), fructose oligosaccharides (FOS), inulin (IN), and resistant dextrin (RD)) using a zebrafish model and found that GOS was the most synergistic with WP. We then tested the GOS-WP combination in a mouse model of loperamide (Lop)-induced constipation and found that it significantly improved constipation symptoms. Specifically, GOS-WP shortened the first black stool time, increased the number of defecation particles, accelerated small intestinal propulsion rate, and increased fecal water content. GOS-WP also normalized the colonic water transport system by inhibiting colonic AQP4/8expression. Additionally, GOS-WP reversed Lop-induced morphological damage in the ileum and colon, increased colonic barrier, and reduced inflammation in mice. Furthermore, 16S rRNA gene sequence analysis showed that GOS-WP reversed the gut microbiota structure changes induced by Lop. GOS-WP significantly increased butyric acid and decreased BCFA levels, indicating improved gut health. Our findings suggest that the GOS-WP combination has potential as a novel intervention for constipation relief. This study highlights the potential of combining prebiotics and WP as a therapeutic strategy for constipation.

Amorphous indium–gallium–zinc-oxide thin film transistors (α-IGZO TFTs) with damage-free back channel wet-etch (BCE) process were achieved by introducing a carbon nanofilm as a barrier layer. We investigate the effects of different source-and-drain (S/D) materials on TFT performance. We find the TFT with Ti/C S/D electrodes exhibits a superior performance with higher output current, lower threshold voltage, and higher effective electron mobility compared to that of Mo/C S/D electrodes. Transmittance electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) are employed to analysis the interfacial interaction between S/D metal/C/α-IGZO layers. The results indicate that the better performance of TFTs with Ti/C electrodes should be attributed to the formations of Ti–C and Ti–O at the Ti/C-contact regions, which lead to a lower contact resistance, whereas Mo film is relatively stable and does not react easily with C nanofilm, resulting in a nonohmic contact behavior between Mo/C and α-IGZO layer. However, both kinds of α-IGZO TFTs show good stability under thermal bias stress, indicating that the inserted C nanofilms could avoid the impact on the α-IGZO channel regions during S/D electrodes formation. Finally, we successfully fabricated a high-definition active-matrix organic lighting emitting diode prototype driven by α-IGZO TFTs with Ti/C electrodes in a pilot line.

Amorphous indium–zinc-oxide thin film transistors (IZO-TFTs) with damage-free back channel wet-etch (BCE) process were investigated. A carbon (C) nanofilm was inserted into the interface between IZO layer and source/drain (S/D) electrodes as a barrier layer. Transmittance electron microscope images revealed that the 3 nm-thick C nanofilm exhibited a good corrosion resistance to a commonly used H3PO4-based etchant and could be easily eliminated. The TFT device with a 3 nm-thick C barrier layer showed a saturated field effect mobility of 14.4 cm2V–1s–1, a subthreshold swing of 0.21 V/decade, an on-to-off current ratio of 8.3 × 1010, and a threshold voltage of 2.0 V. The favorable electrical performance of this kind of IZO-TFTs was due to the protection of the inserted C to IZO layer in the back-channel-etch process. Moreover, the low contact resistance of the devices was proved to be due to the graphitization of the C nanofilms after annealing. In addition, the hysteresis and thermal stress testing confirmed that the usage of C barrier nanofilms is an effective method to fabricate the damage-free BCE-type devices with high reliability.

A capping IZO film was used to successfully improve the storage and thermal stabilities of Ag films applied in top-emitting OLEDs (TOLEDs). Ag films at the thickness of 200 nm were prepared by direct current (DC) magnetron sputtering onto glass substrates, after which IZO films of various thicknesses were deposited by radio frequency (RF) sputtering. It was found that the optimized Ag/IZO films showed no deterioration in reflectance after accelerated aging tests. SEM and XRD results revealed that the void-free capping IZO films could efficiently prevent Ag films from tarnishing and agglomerating. Additionally, the patterning property, surface roughness and resistivity of the composite Ag/IZO film have been characterized and show good potential when used as the reflective electrode in TOLEDs. Finally, green TOLEDs using Ag/IZO as the anode were fabricated. Compared with the conventional single-layer Ag anode, the luminance efficiency at 1000 cd/m2 increased from 17.6 cd/A to 22.0 cd/A. The half-life was extended by 42.7%.

Hydrogen peroxide (H2O2) was used as the etchant for patterning Mo source/drain (S/D) electrodes directly on the indium zinc oxide (IZO) semiconductor films. It was found that the edges of the Mo pattern were oxidized during etching, which was ascribed to the lateral penetration of the H2O2 etchant from the edges of the overlying photoresist. By adding alkali to the H2O2 etchant, the etch rate of Mo could be accelerated with an etch rate selectivity of Mo to IZO of as high as 4 x 104, and the edge-oxidization effect could be greatly reduced. Thin-film transistor (TFT) fabricated with this method exhibited an electron mobility of 11.5 cm2V[?]1s[?]1. The device also showed good electrical stability under positive or negative gate bias stress.

Back‐channel‐etched (BCE) thin‐film transistors (TFTs) with an InGaO/InZnO stacked channel are developed, in which the InGaO and InZnO provide a highly acid‐resistant back channel and a high‐mobility front channel, respectively. The electrical performance of the TFT is optimized by adjusting the InGaO thickness. The best performance is achieved for the TFT with 10 nm thick InGaO. A thinner InGaO layer leads to inferior performance due to damage during the back‐channel‐etching process, while a thicker InGaO layer results in a hump effect and significant negative shifts in the threshold voltage (Vth) and turn‐on voltage (Von), which should be ascribed to the large total carrier number in the channel. The optimal TFT exhibits a high saturated field‐effect mobility of 28.9 cm2 V−1s−1, a near‐zero Vthof −0.17 V, a Vonof −0.49 V, a low subthreshold swing of 0.12 V dec−1, a high on‐to‐off current ratio of 3.5 × 109, and a low contact resistance between the source/drain (S/D) electrodes and channel. The TFT also exhibits high stability under bias thermal stress. Back‐channel‐etched thin‐film transistors (TFTs) with an InGaO/InZnO stacked channel are developed, in which the InGaO and InZnO provide a highly acid‐resistant back channel and a high‐mobility front channel, respectively. The optimal TFT exhibits excellent electrical performance with a high saturated field‐effect mobility of 28.9 cm2V−1s−1. The TFT also exhibits high stability under bias thermal stress.

A crystalline indium-gallium-oxide (InGaO) was used as the channel of a thin film transistor (TFT) with back-channel-etched (BCE) structure. The effects of deposition temperature (T) on crystal structure, morphology, electrical properties and corrosion resistance of InGaO films were studied in detail. X-ray diffraction spectra and scan electron microscopy reveal that the slight increase in corrosion resistance with Tat 25–200°C results from the discrete crystallites embedded amorphous network while the massive increase at 290°C results from the high crystallinity of the film. The carrier concentration (Nc) and mobility of InGaO films show a huge increase as Tincreases due to the crystallization process at 25–200°C, but they change very little when the films are highly crystallized at 290°C. The BCE TFT exhibits a slightly higher saturated mobility of 11.9 cm2/(V·s), a more positive threshold voltage of −0.43 V, a larger subthreshold swing of 0.37 V/decade and a higher off-current of 4 pA when compared with the TFT fabricated by a lift-off process. Combined with X-Ray Photoelectron Spectroscopy analysis, the BCE process causes an oxygen-deficient back channel and introduces deep trap states, leading to the deterioration in electrical performance.

Patient–physician mistrust has become deeply embedded in medical clinics within a wide variety of settings, including many in China. The purpose of this research was to develop a series of actionable policy recommendations to rebuild patient–physician trustin China.

A capping IZO film was used to successfully improve the storage and thermal stabilities of Ag films applied in top-emitting OLEDs (TOLEDs). Ag films at the thickness of 200 nm were prepared by direct current (DC) magnetron sputtering onto glass substrates, after which IZO films of various thicknesses were deposited by radio frequency (RF) sputtering. It was found that the optimized Ag/IZO films showed no deterioration in reflectance after accelerated aging tests. SEM and XRD results revealed that the void-free capping IZO films could efficiently prevent Ag films from tarnishing and agglomerating. Additionally, the patterning property, surface roughness and resistivity of the composite Ag/IZO film have been characterized and show good potential when used as the reflective electrode in TOLEDs. Finally, green TOLEDs using Ag/IZO as the anode were fabricated. Compared with the conventional single-layer Ag anode, the luminance efficiency at 1000 cd/m2increased from 17.6 cd/A to 22.0 cd/A. The half-life was extended by 42.7%.

Hydrogen peroxide (H2O2) was used as the etchant for patterning Mo source/drain (S/D) electrodes directly on the indium zinc oxide (IZO) semiconductor films. It was found that the edges of the Mo pattern were oxidized during etching, which was ascribed to the lateral penetration of the H2O2etchant from the edges of the overlying photoresist. By adding alkali to the H2O2etchant, the etch rate of Mo could be accelerated with an etch rate selectivity of Mo to IZO of as high as 4 × 104, and the edge-oxidization effect could be greatly reduced. Thin-film transistor (TFT) fabricated with this method exhibited an electron mobility of 11.5 cm2V−1s−1. The device also showed good electrical stability under positive or negative gate bias stress.