Search

Laboratory experiments are performed to study the effect of T.Ca content in the molten steel on the composition, size, and quantity of inclusions. Different amounts of SiCa alloys are added into the molten steel to obtain samples with varied T.Ca contents. Samples are taken at 1, 5, 10, 15, and 20 min after the calcium addition to study the transformation of inclusions with time. After the addition of calcium into the molten steel, the size of pure liquid inclusions is small which are more difficult to be removed from the molten steel than solid ones, while partially liquid inclusions are easily removed from the molten steel so that the total oxygen content of the molten steel is lower. The size of solid inclusions is large due to their large coagulation coefficient value. The number density and area fraction of liquid inclusions are larger than solid inclusions due to the higher adhesion work required for the removal of liquid inclusions. The corrosion of MgO crucible easily occurs by the dissolved calcium in the molten steel. Then, the reaction between the reduced magnesium and inclusions in the molten can occur, leading to the generation of MgO–Al2O3 and CaO–MgO–Al2O3 inclusions. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy and safety of selective aneurysmal sac neck-targeted embolization in endovascular aneurysm repair (EVAR) in patients with a hostile neck anatomy (HNA). Materials and methods: Between October 2020 and June 2022, patients with an abdominal aortic aneurysm (AAA) and HNA who underwent EVAR with a low-profile stent graft and a selective aneurysmal sac neck-targeted embolization technique were analysed. An HNA was defined by the presence of any of the following parameters: infrarenal neck angulation > 60°; neck length < 15 mm; conical neck; circumferential calcification ≥ 50%; or thrombus ≥ 50%. Before occluding the entire aneurysm during the procedure, a buddy wire was loaded prophylactically into the sac through the contralateral limb side. If a type Ia endoleak (ELIa) occurred and persisted despite adjunctive treatment such as balloon moulding or cuff extension, this preloaded wire could be utilized to enable a catheter to reach the space between the stent graft and sac neck to perform coil embolization. In the absence of ELIa, the wire was simply retracted. The primary outcome of this study was freedom from sac expansion and endoleak-related reintervention during the follow-up period; secondary outcomes included technical success and intraoperative and in-hospital postoperative complications. Results: Among the 28 patients with a hostile neck morphology, 11 (39.5%) who presented with ELIa underwent intraprocedural treatment involving sac neck-targeted detachable coil embolization. Seventeen individuals (60.7%) of the total patient population did not undergo coiling. All patients in the coiling group underwent balloon moulding, and 2 patients additionally underwent cuff extension. In the noncoiling group, 14 individuals underwent balloon moulding as a treatment for ELIa, while 3 patients did not exhibit ELIa during the procedure. The coiling group showed longer operating durations (81.27 ± 11.61 vs. 70.71 ± 7.17 min, P < 0.01) and greater contrast utilization than the noncoiling group (177.45 ± 52.41 vs. 108.24 ± 17.49 ml, P < 0.01). In the entire cohort, the technical success rate was 100%, and there were no procedure-related complications. At a mean follow-up of 18.6 ± 5.2 months (range 12–31), there were no cases of sac expansion (19 cases of sac regression, 67.86%; 9 cases of stability, 32.14%) or endoleak-related reintervention. Conclusions: Selective aneurysmal sac neck-targeted embolization for the treatment of ELIa in AAA patients with an HNA undergoing EVAR is safe and may prevent type Ia endoleak and related sac expansion after EVAR. [ABSTRACT FROM AUTHOR]

A kinetic model for the Ruhrstahl–Heraeus (RH) desulfurization process is established based on the FactSage Macro Processing. The desulfurizer addition, the desulfurization reaction, the steel mixing, the flow circulation, and the desulfurizer floating during the RH refining process are considered in the model. Simulated results agree well measured results, indicating that the current model can be used to predict the desulfurization reactions during the RH refining process. The CaO activity increases with a higher CaO/Al2O3 ratio and a lower SiO2 content, which exhibits a similar tendency with the desulfurization ratio. It is indicated that it is necessary to increase the CaO activity in the desulfurizer to improve the desulfurization ratio. The S content in the molten steel decreases with time and a higher ratio of the powder blowing. The cost increases with time due to the refractory erosion and the steam consumption. The cost of the desulfurizer added by the powder blowing is lower than that of the gravity sinking. [ABSTRACT FROM AUTHOR]

Mn2Mo3O8/C nanotubes are successfully reshaped from micron-sized MnMoO4 blocks using a simple microwave-combined calcination method with dopamine as both scissors and carbon source. The synthesized Mn2Mo3O8/C nanotube (MMOC-2) exhibits enhanced sodium storage performance as anodes for half-cell (217 mA h g−1 with ca. 99% coulombic efficiency after 500 cycles) and full-cell (capacity retention of 75% after 100 cycles), which is attributed to the uniquely reshaped nanostructures with abundant active sites, short ion diffusion path and fast charge transfer. [ABSTRACT FROM AUTHOR]

Carbon fiber–reinforced polymer (CFRP) composites are widely utilized in the aerospace industry due to their exceptional mechanical properties. In this paper, a regular dodecagon trajectory side milling method was employed to investigate the high-speed cutting performance of CFRP, focusing on the impact of fiber cutting angle, up milling and down milling, processing parameters, and cooling conditions on the cutting characteristics. Results indicate that utilizing the Gr-NMQL cutting lubrication method can significantly improve machining surface quality while reducing cutting force by up to 15%. Additionally, using a PCD burr milling cutter, the normal and tangential cutting forces followed a particular trend: 60° > 30° > 90° > 0° > 150° > 120°. Moreover, when the cutting speed exceeded 200m/min, both normal and tangential cutting forces showed a significant decrease. Cutting along the fiber direction yielded superior machining quality compared to it, and the optimal surface roughness was achieved when cutting along the 90° direction. Finally, a comparative study of up milling and down milling revealed that implementing the up milling process improved both cutting force and surface quality. These findings contribute to a deeper understanding of the high-speed milling performance of CFRP and provide insights for optimizing the machining process. [ABSTRACT FROM AUTHOR]

Sulfides like MnS are common phases in resulfurized free‐cutting steels, and are required to be controlled during the hot working process due to its influence on machinability, mechanical, and physical properties of final products. This article extensively reviews published researches on sulfides in resulfurized free‐cutting steels. The formation mechanism and modification of MnS during steelmaking, casting, and heat treatment are discussed based on a number of relevant studies. Measures to control the morphology and number of sulfides are supplied, which are beneficial for the production of resulfurized free‐cutting steels with high quality. Thermodynamic calculation proves to be an effective method to predict and control sulfides. [ABSTRACT FROM AUTHOR]

Skeletons play an important role in the human body, and can form gaps of varying sizes once damaged. Bone defect healing involves a series of complex physiological processes and requires ideal bone defect implants to accelerate bone defect healing. Traditional grafts are often accompanied by issues such as insufficient donors and disease transmission, while some bone defect implants are made of natural and synthetic polymers, which have characteristics such as good porosity, mechanical properties, high drug loading efficiency, biocompatibility and biodegradability. However, their antibacterial, antioxidant, anti-inflammatory and bone repair promoting abilities are limited. Flavonoids are natural compounds with various biological activities, such as antitumor, anti-inflammatory and analgesic. Their good anti-inflammatory, antibacterial and antioxidant activities make them beneficial for the treatment of bone defects. Several researchers have designed different types of flavonoid-loaded polymer implants for bone defects. These implants have good biocompatibility, and they can effectively promote the expression of angiogenesis factors such as VEGF and CD31, promote angiogenesis, regulate signaling pathways such as Wnt, p38, AKT, Erk and increase the levels of osteogenesis-related factors such as Runx-2, OCN, OPN significantly to accelerate the process of bone defect healing. This article reviews the effectiveness and mechanism of biomaterials loaded with flavonoids in the treatment of bone defects. Flavonoid-loaded biomaterials can effectively promote bone defect repair, but we still need to improve the overall performance of flavonoid-loaded bone repair biomaterials to improve the bioavailability of flavonoids and provide more possibilities for bone defect repair. [ABSTRACT FROM AUTHOR]

The localized corrosion induced by different kinds of inclusions in low‐nickel stainless steel is studied through immersion tests and first‐principles calculations. The galvanic corrosion between the steel matrix and different kinds of inclusions occurs in the corrosive environment due to the difference in the electron work function of the steel matrix and inclusions. The electron work function of MnS, CeS, and Ce‐O‐S is smaller than that of the steel matrix, thus, these inclusions first dissolve as the anode. However, the electron work function of cerium‐containing oxides is bigger than that of the steel matrix, and the steel matrix dissolves prior to cerium‐containing oxides. The order of the volume expansion rate of pits induced by inclusions is CeS > Si‐Mn(‐Al)‐O > MnS > Ce‐C‐O‐S > Ce‐Si‐Mn(‐Al)‐O > Ce‐O‐S. For cerium‐containing inclusions, the electron work function of inclusions increases with the increase of the O/Ce ratio and the S/Ce ratio of inclusions. The order of the electron work function of cerium‐containing inclusions is cerium oxides > cerium sulfides > cerium oxysulfide. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe 2 TiO 5 /NiCo-LDH composite photoelectrode exhibits dual role as heterojunction and co-catalyst. • The effect of surface state on charge transfer is systematically discussed. • Fe 2 TiO 5 /NiCo-LDH photoelectrode expands application in photoelectrochemistry for sulfide oxidation reaction. The Fe 2 TiO 5 photoelectrode is limited in photoelectrochemical field (PEC) due to the slow charge transfer kinetics, short carrier diffusion distances and low separation efficiency. Hence, the Fe 2 TiO 5 /NiCo-LDH photoelectrodes with dual roles of co-catalyst and heterojunction are constructed, in which the photogenerated carriers are effectively separated and the conductivity is enhanced. At the same time, the surface state of the Fe 2 TiO 5 -based photoanode is modulated by the co-catalyst, which drives charge transfer into the electrolyte. With the synergistic effect of inhibiting photogenerated carrier complexation and accelerating charge transfer, the OER photocurrent density of Fe 2 TiO 5 /NiCo-LDH photoelectrode is enhanced to 2.42 mA/cm2, which is 3.4 folds higher than that of pristine Fe 2 TiO 5. Specifically, Fe 2 TiO 5 /NiCo-LDH photoanode exhibits good stability and photoelectrochemical performance in hydrogen sulfide oxidation reaction (SOR). Similar to the OER, the sulphur oxidation photocurrent density of Fe 2 TiO 5 /NiCo-LDH photoelectrodes is enhanced to 0.21 mA/cm2, which is 2 folds higher than that of pristine Fe 2 TiO 5. This work provides a new idea for the modification of Fe 2 TiO 5 photoanodes and also explores a pioneering demonstration for the photoelectrochemical decomposition of hydrogen sulfide. [ABSTRACT FROM AUTHOR]

The generation mechanism of stratospheric gravity waves (SGWs) in tropical cyclones (TCs) is investigated with an idealized experiment using numerical model. The results show that there are two peaks of SGW amplitude during the mature period of TC, one above the eyewall and the other above the rainband. The SGWs can only exist in unbalanced flow, so a simplified balance equation suitable for the special structure of the TC is proposed to investigate the SGWs. Diagnosis of this equation shows there is significant unbalanced flow around the eyewall and rainband caused by the convection and the vertical shear between outflow and compensating inflow. Diagnosis of the source function indicates that diabatic heating and mechanical oscillations are the main mechanisms generating the SGWs above the eyewall and rainband. The Kelvin–Helmholtz instability induced by vertical shear also makes a non‐negligible contribution to the generation of SGWs above the rainband. Plain Language Summary: As intense convective systems, tropical cyclones (TCs) can generate intense stratospheric gravity waves (SGWs). However, TCs contain many unique structures such as the eyewall, spiral rainband, outflow layer, and inflow layer. How are the SGWs distributed in TCs and what effect does TC structure have on the generation of SGWs? Here we find there are two peaks of SGW amplitude during the mature period of TCs, one above the eyewall and one above the rainband. They appear mainly in the unbalanced flow regions, and the unbalanced flow in TCs is generated by convection around the eyewall and rainband and the vertical shear of the radial wind caused by outflow above the rainband. Thus, the convection and vertical shear play key roles in the generation of SGWs in TCs. Diabatic heating is the main mechanism generating SGWs above the eyewall and rainband by convection. Meanwhile, mechanical oscillation also generates convective SGWs above the eyewall. The Kelvin–Helmholtz instability induced by the vertical shear also makes a non‐negligible contribution to the generation of SGWs above the rainband. Key Points: There is significant unbalanced flow that can generate stratospheric gravity waves around the eyewall and rainband of tropical cyclonesThe unbalanced flow is generated by convection and vertical shear of the radial wind around the eyewall and outflow above the rainbandDiabatic heating, mechanical oscillation, and Kelvin–Helmholtz instability contribute to the generation of stratospheric gravity waves [ABSTRACT FROM AUTHOR]

The skin, the largest organ in the human body, mainly plays a protective role. Once damaged, it can lead to acute or chronic wounds. Wound healing involves a series of complex physiological processes that require ideal wound dressings to promote it. The current wound dressings have characteristics such as high porosity and moderate water vapor permeability, but they are limited in antibacterial properties and cannot protect wounds from microbial infections, which can delay wound healing. In addition, several dressings contain antibiotics, which may have bad impacts on patients. Natural active substances have good biocompatibility; for example, ginsenoside Rg3 has anti-inflammatory, antibacterial, antioxidant, and other biological activities, which can effectively promote wound healing. Some researchers have developed various polymer wound dressings loaded with ginsenoside Rg3 that have good biocompatibility and can effectively promote wound healing and reduce scar formation. This article will focus on the application and mechanism of ginsenoside Rg3-loaded dressings in wounds. [ABSTRACT FROM AUTHOR]

Heavy metals (HMs) in sewage sludge (SS) are major obstacles that limit the land application of SS. Although the removal of HMs with acid leaching and cation exchange resins (CER) adsorption has been investigated, neither process alone could meet the simultaneous demand for efficient HMs removal and good preservation of nutrients. In this report, sulfuric acid (H2SO4) and acetic acid (AC) were used to dissolve HMs from the SS, and subsequent CER adsorption was conducted to selectively extract the HMs from acid leachate. With the addition of 5 mmol/L H2SO4, the maximum leaching efficiency of Ni, Cu, Zn and Fe were 64.0%±2.7%, 29.0%±3.7%, 98.4%±4.1% and 16.4%±0.3%, respectively. No significant inhibition effect of Fe in the leachate on the HMs adsorption with CER has been observed. The CER with sulfonate groups (R-SO3H) showed higher Ni, Cu and Zn adsorption efficiency than the CER with thioureido groups (R-SH) and carboxylic groups (R-COOH) in the acid leachate. The optimal operation condition with a combined usage of H2SO4 and R-SO3H is characterized by the advantages of high HM removal efficiency, affordable cost, and low energy consumption through the evaluation with the triangulation model. [ABSTRACT FROM AUTHOR]

Coupling fluid flow, heat transfer, solidification, and particle dissolution behavior, the white spot formation in the vacuum arc remelting process is simulated. The effect of particle initial diameter, dropping position, and dropping height on the remelting behavior is investigated. The results show that the particle from the electrode drops through the arc zone with gravity force and the diameter is reduced in the high‐temperature zone. As the diameter is lower than 5 mm, the particle completely dissolves and the white spot formation can be eliminated. The particle dissolution is less affected by the liquid pool depth, but it is mainly affected by the high‐temperature zone distribution, which is closely related to the electric arc generation. Because of the limited high‐temperature zone near the ingot side surface, the particle from the ingot crown is more difficult to remelt, compared with that from the electrode. Moreover, it is found that the dropping height obviously affects the particle remelting behavior. As the dropping height decreases from 25 to 0, the particle critical diameter that can fully dissolve increases from 4.2 to 6.6 mm. [ABSTRACT FROM AUTHOR]

Background: NUPR1, or p8, is a small chromatin protein that plays a central role in the resistance to treatment and progression of cancer. Nevertheless, the molecular mechanism of NUPR1 in bladder cancer (BLCA) remains unclear. Methods: We used online databases and immunohistochemistry (IHC) to explore the expression of NUPR1 in BLCA tissues and controls. Lentivirus‐mediated small interfering ribonucleic acid (siRNA) was used to knockdown the expression of NUPR1 in two human BLCA cell lines. We used an in vivo experiment to investigate the effect of NUPR1 knockdown on the growth of BLCA. Moreover, an in silico analysis was conducted to assess the differential expression profile after NUPR1 interference. The CIBERSORT algorithm was utilized to evaluate the effects of tumor‐infiltrating immune cells among BLCA patients. Results: The expression of NUPR1 in BLCA tissues was significantly higher than in the control. NUPR1 expression was also positively correlated with the stage of BLCA. After lentivirus‐mediated interference, the expression of NUPR1 was significantly down‐regulated in BLCA cell lines. The cell cycle was blocked in G1 phase and the cell proportion of S phase was decreased in both two cell lines. Moreover, in vivo experiment revealed that the tumor growth of BLCA can be delayed by inhibiting the expression of NUPR1. Both in silico analysis and functional experiments revealed that NUPR1 was correlated with epithelial–mesenchymal transition (EMT). We also revealed that macrophages were the most related immune cells associated with the expression of NUPR1 in BLCA. Conclusions: This study suggests that NUPR1 plays a carcinogenic role in BLCA. NUPR1 lentivirus‐mediated interference could interfere with cycle progression of the BLCA cell, resulting in cell cycle arrest in the G1‐phase. The carcinogenic effect of NUPR1 in BLCA is likely achieved through EMT. NUPR1 is correlated with the M0‐type macrophage markers CD68 and CD11b‐integrin. [ABSTRACT FROM AUTHOR]

The anomalous movements of glaciers cause disasters, such as debris flows and landslides. It is very important to assess the glacier movements and their future trends. Glacier velocity refers to movement process. The current research aims to analyse past and current spatiotemporal changes in glacier velocity. No study has used neural network model to conduct a spatiotemporal prediction for glacier velocity. Therefore, this paper selected typical mountain glaciers G2 and G5 along the Sichuan-Tibet Railway as research objects and constructed the Convolutional Gate Recurrent Unit (ConvGRU) spatiotemporal prediction model based on 1988–2018 Landsat data to predict velocities in 2019–2028, and analysed the future trends of G2 and G5. The evaluation indexes met the model requirements to a large extent, quantitatively showing that the model has high accuracy and can successfully capture the fluctuation changes in time series data of glacier velocity. The mean deviations of G2 and G5 were 0.09 and −0.47 m/yr, respectively, reflecting the high reliability of the model applied to extraction of glacier velocity. The velocities of G2 and G5 showed a slow downtrend with fluctuations; that is, they will not cause damage to the construction and operation of the Sichuan-Tibet Railway in the short term. [ABSTRACT FROM AUTHOR]

The influence of stratospheric gravity waves (SGWs) on the intensity of convection (CI) in the area of heavy precipitation around Typhoon Lekima (2019) is studied. Using theory and simulations, the energy and phase of the SGWs are shown to propagate upward and downward. The SGWs can propagate downward into the areas of convective instability in the upper troposphere in 35–85 min. Downward‐propagating SGWs can promote the release of convective instability energy, so the CI is enhanced. The relationship between SGWs and CI after 85 min is studied using a two‐layer model hypothesis for both a linear regression model and a Long Short‐Term Memory neural network model (nonlinear). The relationship is shown to be primarily linear (nonlinear) when the SGWs are weak (intensive). Therefore, the SGWs may be used as a proxy for the CI. Plain Language Summary: The source of convection is typically investigated in the troposphere, ignoring the role of the stratosphere. The energy of stratospheric gravity waves (SGWs) generated by convection propagates upward. Accompanying the upward energy propagation, SGWs can propagate downward into the troposphere; however, it remains unclear whether and how the SGWs influences convection in the troposphere. To answer this question, the relationship between the SGWs and convection during Typhoon Lekima 2019 has been studied. The vertical phase speed and intensity of the SGWs are large, which means that the SGWs can propagate downward into the troposphere. The SGWs can promote the release of the instability energy and enhance the intensity of convection (CI). A linear regression and a Long Short‐Term Memory neural network model are used to fit the CI with a lag of 85 min by the SGWs. The relative errors are only 9.3% and 5.8%, which indicates a strong linear relationship between the SGWs and convection in the troposphere. Nevertheless, the small error derived from the nonlinear model shows that the role of nonlinear interaction cannot be ignored, especially when the SGWs are strong. Therefore, the SGWs may be used as a proxy for CI prediction. Key Points: The stratospheric gravity waves (SGWs) with downward propagating phase can reach down into the troposphereDownward‐propagating gravity waves promote the release of convective instability energy in the upper troposphereThe intensity of SGWs can be used as a proxy for the intensity of the convection [ABSTRACT FROM AUTHOR]

Cerebral stroke (CS) is a heterogeneous syndrome caused by multiple disease mechanisms. Ischemic stroke (IS) is a subtype of CS that causes a disruption of cerebral blood flow with subsequent tissue damage. Noncontrast computer tomography (NCCT) is one of the most important IS detection methods. It is difficult to select the features of IS CT within computational image analysis. In this paper, we propose AC-YOLOv5, which is an improved detection algorithm for IS. The algorithm amplifies the features of IS via an NCCT image based on adaptive local region contrast enhancement, which then detects the region of interest via YOLOv5, which is one of the best detection algorithms at present. The proposed algorithm was tested on two datasets, and seven control group experiments were added, including popular detection algorithms at present and other detection algorithms based on image enhancement. The experimental results show that the proposed algorithm has a high accuracy (94.1% and 91.7%) and recall (85.3% and 88.6%) rate; the recall result is especially notable. This proves the excellent performance of the accuracy, robustness, and generalizability of the algorithm. [ABSTRACT FROM AUTHOR]

COSMIC-2 (Constellation Observing System for Meteorology, Ionosphere and Climate- 2) dry temperature profile data from December 2019 to November 2021 are used to study stratospheric gravity waves (GWs) in the Asian monsoon region. The stratosphere between 20 and 50 km is divided into the lower, middle, and high layers based on the vertical distribution of the mean potential energy (Ep) and the horizontal distribution of GW Ep in these three layers, and their seasonal changes are analyzed. The source and propagating mechanism of GWs in middle latitudes in winter are revealed. The results show that GWs in the stratosphere have distinct distribution features during different seasons. The significant Ep in winter appears mainly in middle latitudes north of 30°N, whereas in summer, it appears in the low latitudes south of 30°N. There are significant areas of GW activity in both low and middle latitudes in spring and autumn, but their intensity is significantly weaker than in winter and summer. Areas with significant GWs and the seasonal variation of their intensity are accompanied by the Asian monsoon activity. In winter, there is a northward and upward propagating column for GWs above the Sichuan Basin, and in summer, there is an eastward and upward propagating column for GWs in the zonal band 15–25°N. The occurrence of GWs in northwestern China in winter is the result of the subtropical jet stream and topography. Once GWs enter the stratosphere, they are regulated by the winter stratospheric environment, and the GWs acquire a northerly component by the wind shear. The meridional wind shear in the background field is an important factor affecting the development and propagation of GWs. [ABSTRACT FROM AUTHOR]

Acoustic tomography is a widely used non-contact method for visualizing temperature distribution. A temperature distribution reconstruction algorithm based on an improved sparse reconstruction model and multi-scale feature fusion network is proposed. First, the acoustic temperature measurement sparse reconstruction model is improved by combining the error function (ERF) and the iterative reweighting algorithm, and the alternating direction method of multipliers algorithm (ADMM) is used to solve the model to obtain the initial temperature distribution. Then the feature extraction network is constructed to extract multi-scale features of acoustic time of flight (TOF) as prior information. Finally, the feature fusion reconstruction network is constructed to fuse and reconstruct the initial temperature distribution and multi-scale features to obtain a high-precision temperature distribution. Simulation and experimental tests were conducted respectively, and compared with other algorithms. The results show that the average relative error and root mean square error of the simulated temperature distribution reconstruction are 0.073% and 0.1% respectively, the average reconstruction error of the temperature points set in the experimental test is 0.38%, and the reconstruction errors are lower than other algorithms. The proposed method effectively utilizes prior information to correct sparse reconstruction temperature distribution reconstruction results, significantly improving the quality of temperature distribution reconstruction. [Display omitted] • Acoustic tomography technology is used for temperature distribution reconstruction. • The improved sparse reconstruction model can improve the accuracy of initial temperature distribution reconstruction. • The feature extraction network can perform multi-scale feature extraction on the time-of-flight of acoustic waves. • The feature fusion reconstruction network can improve the utilization of prior information. [ABSTRACT FROM AUTHOR]

Acoustic tomography is a widely used non-contact method for visualizing temperature distribution. A temperature distribution reconstruction algorithm based on an improved sparse reconstruction model and multi-scale feature fusion network is proposed. First, the acoustic temperature measurement sparse reconstruction model is improved by combining the error function (ERF) and the iterative reweighting algorithm, and the alternating direction method of multipliers algorithm (ADMM) is used to solve the model to obtain the initial temperature distribution. Then the feature extraction network is constructed to extract multi-scale features of acoustic time of flight (TOF) as prior information. Finally, the feature fusion reconstruction network is constructed to fuse and reconstruct the initial temperature distribution and multi-scale features to obtain a high-precision temperature distribution. Simulation and experimental tests were conducted respectively, and compared with other algorithms. The results show that the average relative error and root mean square error of the simulated temperature distribution reconstruction are 0.073% and 0.1% respectively, the average reconstruction error of the temperature points set in the experimental test is 0.38%, and the reconstruction errors are lower than other algorithms. The proposed method effectively utilizes prior information to correct sparse reconstruction temperature distribution reconstruction results, significantly improving the quality of temperature distribution reconstruction. [Display omitted] • Acoustic tomography technology is used for temperature distribution reconstruction. • The improved sparse reconstruction model can improve the accuracy of initial temperature distribution reconstruction. • The feature extraction network can perform multi-scale feature extraction on the time-of-flight of acoustic waves. • The feature fusion reconstruction network can improve the utilization of prior information. [ABSTRACT FROM AUTHOR]

The effect of Ta addition on characterization of primary MC carbides with regard to their morphology, composition, and size in Ti-Nb-Mo-W-alloyed Ni-based superalloy were investigated. Several tools including automated scanning electron microscopy as well as electrolytic etching technology were used for broad characterization of carbides including three-dimensional morphology. The addition of Ta significantly influences the composition and morphology of primary MC carbides. Large dendrite (Ti,Nb,W,Mo)C carbides were changed to smaller (Ta,Ti,Nb)C carbides. The hardness of both MC primary carbides and the matrix were increased. MC carbides in the studied superalloys were developed dendrite in three-dimensional morphology, which was much larger than that in two-dimensional morphology. The formation mechanism of carbides was clarified by thermodynamic calculation. • Ta addition changed the composition and size of primary carbides significantly. • Ta addition increased the hardness of both MC primary carbides and the matrix. • Automated SEM was used to automatically analyze the characteristic of carbides. • Electrolytic etching technology was used for 3D characterization of carbides. [ABSTRACT FROM AUTHOR]

The first-order phase transition compounds have attracted widespread attention from refrigeration enterprises and scientists due to their giant magnetocaloric effect and refrigeration temperature region spanning room temperature. Magnetic substances are crystal structures composed of magnetic ions or atoms with a certain thermal motion or vibration. This research mainly discusses the multisource coordination optimization of magnetic declination thermoelectric material efficient power generation device and distribution network. In this study, large doses of MnFe(P,Si) compounds with different ratios were prepared. The reason for choosing a large dose is that the properties and structures of the samples prepared in a large amount and a small amount will be more or less the same for the samples fired in the same proportion and in the same process. At the same time, mass production also prepares for future mass production. Thermomagnetic power generation described in this study is a form of power generation that converts thermal energy directly into electrical energy. The conversion of thermal energy to electric energy is realized by the change of magnetization in the closed coil by the thermomagnetic material in the magnetic field environment, and then, the change of the magnetic flux in the closed coil is realized. The distribution network refers to the power network that receives electrical energy from the transmission network or regional power plants and distributes it locally through distribution facilities or distributes it to various users step by step according to the voltage. It is composed of overhead lines, cables, towers, distribution transformers, isolating switches, reactive power compensators, and some ancillary facilities. A network that plays an important role in distributing electrical energy in the power grid. This research starts with the active distribution network scheduling priority and the distribution network scheduling coordination control framework. Combined with the scheduling and operation characteristics of each component in the distribution network, the coordinated optimization scheme of the distribution network and the source-network load-storage coordinated control framework are investigated and analyzed. The scheduling resources of the model include the power of the substation flowing into the distribution network, the output of the adjustable distributed power source, the output value of the energy storage element, the closing status of the tie switch, and the section switch. In the study, it was found that when the Fe content was 0.63, the Curie temperature of the compound could reach 273 K at the highest. Scientifically designing a thermomagnetic power generation demonstration device is an important part of the realization of thermomagnetic power generation. The magnetic declination thermoelectric materials designed in this study will help to improve the power generation efficiency. [ABSTRACT FROM AUTHOR]

A high-resolution simulation with the Weather Research and Forecasting (WRF) model is performed to investigate the characteristics of the horizontal kinetic energy (HKE) spectra of an eastward-moving southwest vortex (SWV) generated in Sichuan Province, China, during 16–19 June 2011. The results indicate that the evolution of the SWV can be divided into the development, mature, and decay stages. In the troposphere, the HKE spectrum reproduces the typical atmospheric spectrum, with a slope of approximately −3 for wavelengths greater than 300 km and −5/3 for wavelengths between 300 and 30 km in each stage. The average scale of spectral transition is around 300 km. However, the HKE spectrum in the lower stratosphere shows a −5/3 slope at mesoscales and has no clear spectral transition. During the mature stage of the SWV, the HKE increases prominently for wavelengths between 300 and 30 km. Moreover, the relative contribution of the rotational kinetic energy (RKE) and the divergent kinetic energy (DKE) was investigated. It shows that the RKE spectrum dominates the DKE spectrum for wavelengths greater than 300 km in the lower troposphere, while in the upper troposphere the magnitudes of RKE and DKE are comparable over all scales. However, in the lower stratosphere, the DKE is an order of magnitude larger than the RKE, contributing more to the total HKE spectrum. [ABSTRACT FROM AUTHOR]

A 3D model is built to simulate the transport behavior in the slab continuous casting with mechanical reduction. More importantly, the reduction amounts and reduction positions on the center segregation evolution are investigated. The model is verified by the measured solute segregation and surface temperature. The results show that liquid steel from the submerged entry nozzle (SEN) impacts the slab narrow surface directly, which reduces the solidified shell thickness in the edge part. In later solidification, the bulging amount of the edge part is larger than that of the middle part, which promotes solute‐enriched liquid to move from middle part to edge part and results in serious segregation. When the reduction zone is set at 13−17 m from the meniscus, the center segregation of the middle part is reduced, but that of the edge part becomes more serious, due to the enriched liquid compressed to the edge part. The slab solidification end should be within the reduction zone, both for the middle part and for the edge part. The optimum reduction zone is from 15.0−17.0 m to 16.0−18.0 m, where center segregation in the edge part begins to decrease and that in the middle part remains at a lower level. [ABSTRACT FROM AUTHOR]

The mechanism by which a mid‐latitude trough influenced the gravity waves (GWs) generated by Typhoon Lekima (2019) was studied by changing the initial fields in a series of model experiments. A peak in GW intensity (GWI) develops as typhoons weaken. The vertical speed shows the patterns of GWs generated by the typhoon and trough are the same during this peak GWI period. The typhoon generates the main part of the GWs and the trough enhances their intensity. The phase speed spectra show intense GWs occur when the GWs generated by the typhoon and trough propagate at the same phase speed. The GWI generated by the trough and typhoon were calculated separately in the control experiment, and their sum shows the peak GWI was caused mainly by in‐phase superposition. Finally, the model of the GWs superposition was proposed to quantitatively verify the existence of waves liner positive superposition. Plain Language Summary: Gravity waves (GWs) generated by typhoons are typically strongest as the typhoon intensifies. However, a sudden increase of GWs occurred when Typhoon Lekima (2019) weakened when there was a westerly trough to the north of the typhoon. The assumption of in‐phase superposition between the GWs generated by the typhoon and the trough has been proposed to explain this phenomenon. To verify this assumption, the typhoon and trough were removed from the control experiments so that the GWs were generated by each system alone. The results showed the GW patterns generated by typhoon or trough were the same, as were the speed and direction of GW propagation, which indicates superposition can cause a sudden increase of GW intensity (GWI). The typhoon is the main source of GW generation, but the trough can then intensify these GWs. The difference between the GWI from the control experiment and the sum of the GWI generated separately by the typhoon and the trough was small. Finally, we proposed the model of the GWs superposition to quantitatively verify the existence of waves liner positive superposition. This finding supports that in‐phase superposition played an important role in the GW development. Key Points: The peak intensity of gravity waves (GWs) during typhoon weakening is caused by in‐phase superposition of gravity wavesThe in‐phase superposition occurs when GWs generated by the typhoon and trough maintain the same pattern and phase speedThe typhoon generates the main part of the GWs, whereas the trough enhances the intensity [ABSTRACT FROM AUTHOR]

Immediately after casting, the occurrence of early age shrinkage is sensitive to internal stresses, degree of hydration, and tensile strength, which is of concern to engineers. This study investigated the influences of wind speeds on early‐age shrinkage and tensile strength (strain) of cement paste, and the results were further interpreted by an investigation of hydration degree and capillary water. The outcomes show that as the wind speed increased, the shrinkages (i.e., drying, chemical, and autogenous shrinkage) experienced various trends depending on several factors. Meanwhile, a variety of wind speeds altered the proportion of the evaporation in the capillary water, the inner moisture distribution, and the humidity difference between specimens' surface and their interior sections. Further, tensile strength and elastic modulus were deteriorated by wind, whereas with the growth of the wind speed, the ultimate tensile strain of specimens exhibited various scenarios within and after 24 h. [ABSTRACT FROM AUTHOR]

The spatial distribution of argon bubbles in an 1800 mm × 230 mm continuous casting strand under different casting speeds and argon flow rates are studied through the numerical simulation using the Euler–Euler‐multiple‐size‐group approach. The calculated fluid flow is validated with water modeling and nail board measurements of industrial trials. Argon bubbles with diameter of 2 mm are injected into the submerged entry nozzle (SEN). The speed of the molten steel near the SEN decreased with the casting speed increasing and increased with the argon flow rate increasing. Most of argon bubbles are larger than 4.5 mm inside the mold at the casting speed of 0.6 m min−1 and the argon flow rate of 18 NL min−1. The breakup rate of bubbles inside the mold increased with the increasing of the casting speed and the coalescence rate increased with the increasing of the argon flow rate. The coalescence and breakage of argon bubbles inside the mold mainly occurred during the rising of bubbles to the top surface and the moving of bubbles with the steel jet to the narrow face. The average diameter of bubbles decreased when the casting speed increased and the diameter increased when the argon flow rate increased. [ABSTRACT FROM AUTHOR]

Deep-holes are typical parts of aircraft structures, which is difficult to be machined. Boring assisted with ultrasonic vibration-assisted cutting has been proved to greatly enhance machining performance, especially for Ti6Al4V aviation alloy. This paper focuses on the machining extra-large aspect ratio (exceeding 20) of Ti6Al4V aviation deep-hole with the axial ultrasonic vibration-assisted boring (AUVB) method. First, the kinetics of the AUVB process is analyzed and a retrospective of its separation cutting feature is provided. Subsequently, a multi-stepped cantilever beam model of boring bar is established to analyze its static rigidity and dynamic stability. The aperture error is deduced, and then size coefficient is put forward to represent the static rigidity of the boring bar, which is inversely proportional to the diameter. In addition, two different vibration cases, namely modal-coupling vibration and regenerative vibration are considered for dynamic stability analysis. Next, the morphology of bored surface is analyzed, and the geometric height of peaks formed by AUVB and CB are calculated. Phase shift φ= π is suggested for obtaining a better surface in AUVB. Finally, the feasibility of AUVB on the machining of extra-large aspect ratio Ti6Al4V titanium alloy aviation deep-hole is verified through systematic experiments. Results demonstrate that AUVB has obvious advantages in reducing boring force, improving boring accuracy, suppressing vibration and promoting surface quality. Furthermore, the aperture error decreases to 50% and vibration amplitudes decrease to only 20–25%. The overall surface roughness of the deep-hole part stays below Ra=0.8μm with rotational speeds of 60r/min and 80r/min, and the surface residual stress state is transferred from the tensile state to a compressive one. As a result, not only AUVB can provide better boring accuracy and surface finish, but it also can enhance the surface fatigue properties. [ABSTRACT FROM AUTHOR]

Laboratory experiments are conducted to study the influence of inclusions on the nucleation of acicular ferrite in Ti–Zr‐bearing steels. The ferrite transformation in steels with different Ti–Zr contents is observed using a high‐temperature confocal laser scanning microscope (HT‐CLSM). The average composition and size of inclusions and the information about the nucleation of acicular ferrite (AF) are analyzed using a scanning electron microscope. When the content of titanium in the steel increased from 70 to 370 ppm, the main composition in the inclusion transformed from Al2O3 to Ti2O3, the volume fraction of AF increased from 24.4% to 52.5%. The average content of ZrO2 in inclusions is 0%, 18.51%, and 90.39%, when the Zr content of steel is 0 80, and 140 ppm, the volume fraction of AF is 52.5%, 76.9%, and 56.8%. The relationship between the cosine of the contact angle at the inclusions‐ferrite interface and the diameter of inclusions is established based on experimental results, which is consistent with the results calculated based on the classic nucleation theory. [ABSTRACT FROM AUTHOR]

High-strength concrete (HSC) suffers severe shrinkage, which deteriorates the structural safety of buildings over time. Therefore, this study aims to search for indexes that could reflect the development of early drying shrinkage in HSC with different types/quantities of minerals. The influences of minerals on the internal pore structure and water evaporation of HSC were investigated by experimental work, whose correlation with early drying shrinkage was clarified. The results indicated that pore size distribution (PSD) and water evaporation of HSC should be taken into account simultaneously, facilitating the proposal of a two-factor parameter, r s , and a smaller r s was accompanied by greater drying shrinkage of samples. In addition, only partial mesopore lost water that led to drying shrinkage of HSC instead of water in all mesopores. Finally, an early drying shrinkage model of HSC based on r s was established correspondingly, which was in line with the experimental data, showing great accuracy, suitability and values in practice in reflecting early drying shrinkage behaviors of the HSC selected in this study. However, the current model is based on pore structure parameters obtained from mercury intrusion porosimetry (MIP). The backscattered electron image analysis (BSE-IA) measurement of pore structure indicates that MIP underestimates the content of pores larger than 200 nm. Therefore, the actual parameter r s should be greater than the currently calculated value. In the future, with the development of pore structure testing techniques, a more accurate r s value that closely represents the true value should be obtained, and a more universal model that considers several factors should be established. • Influences of different types/quantities of minerals on HSC were studied. • Correlation between pore structures and water evaporation of HSC were investigated. • The pore structure of HSC was investigated using both MIP and BSE-IA. • A two-factor parameter, r s in HSC was proposed to characterize shrinkage of HSC. • The early drying shrinkage model of HSC based on r s fitted well with the test results. [ABSTRACT FROM AUTHOR]

The wound of diabetes has long-term excessive inflammation leading to wound fibrosis and scar formation. In the process of diabetic wound healing, good wound dressing is required for intervention. In this study, we designed a dihydromyricetin-loaded hydrogel (PCD) based on phellinus igniarius polysaccharide and l-arginine modified chitosan as an alternative material to promote diabetes wound healing. PCD had a uniform porous structure, good thermal stability, excellent mechanical properties, high water absorption, excellent antioxidant and anti-inflammatory activities and good biocompatibility and biodegradability. In addition, in the full-thickness skin trauma model of diabetes, PCD significantly inhibited the JNK signaling pathway to reduce inflammatory response, and significantly down-regulated the expression of TGF-β1, Smad2, Smad3 and Smad4 to directly inhibit the TGF-β/Smad signaling pathway to accelerate wound healing and slow down scar formation in diabetes mice. Therefore, PCD has a broad application prospect in promoting diabetes wound healing. [Display omitted] [ABSTRACT FROM AUTHOR]

• NDVI time series predictions for the Yellow River Basin, China. • Proposed multivariate Long-Short Term Memory neural network incorporating climate elements. • The common constraining effects of multiple climatic factors on NDVI are fully accounted for in the model proposed in the study. Accurate prediction of the trend of Normalized Difference Vegetation Index (NDVI) time series in the Yellow River Basin (YRB) is crucial for the assessment of the hydrological and ecological environment in this region. Currently, the NDVI time series prediction model is primarily based on traditional models and single-variable neural network models. Nevertheless, these models present challenges in considering the limitations of multiple factors, causing the NDVI time series prediction results to lack reliability. To predict NDVI time-series in the YRB of China, this study constructed a multilayer multivariate Long-Short Term Memory (LSTM) neural network model including climatic components. The initial important climatic elements in this region were identified using GeoDetector. Then, the relationship between NDVI and climatic factors in the YRB of China is established. Finally, numerical scale data are used to train and predict a multilayer multivariate LSTM model with climatic components. According to the results, the three-layer multivariate LSTM neural network NDVI time series prediction model developed in this study has the best performance among the evaluated indices. When compared to existing time series prediction models, the proposed model in this study takes into account the common constraint effect of various climate factors on NDVI. This leads to a significantly improved prediction accuracy, presenting new opportunities for enhancing the prediction model. By analyzing the NDVI time series prediction outcomes for the YRB, it has been determined that the ecological environment of the area will continuously improve in the future. This study offers significant technological and theoretical backing for assessing the hydrological and ecological environment of the YRB and comparable ecologically vulnerable regions in China. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the effect of laparoscopic-assisted resection and colorectal anastomosis with a stapling technique in the treatment of Hirschsprung disease (HSCR) in infants. Methods: From June 2018 to January 2019, 25 cases of HSCR diagnosed by clinical examination and pathology were selected at the Children's Hospital, School of Medicine, Zhejiang University, China. All children were treated with standard laparoscopic-assisted transanal endorectal pull-through surgery (the modified Swenson technique). The short segment type and the typical type with a descending colon–rectum anastomosis were both included. The long segment type had an ascending colon–rectal anastomosis after ascending colon turnover. The colorectal anastomosis was divided into traditional manual anastomosis and straight intraluminal stapler (SIS) anastomosis. According to the different methods of anastomosis, the patients were divided into a traditional group and a SIS group. Age, gender, body weight, operation time, blood loss, postoperative anal exhaust and defecation time, postoperative hospitalization time, and postoperative short-term complications were analyzed retrospectively. Results: A total of 25 children were diagnosed with HSCR. There were 17 boys and 8 girls, and their average age was 10.20 months (interquartile range, 8.60–11.30). Their average body weight was 7.90 kg (interquartile range, 7.50–8.40). There were 17 cases of the typical type, 5 cases of the short segment type, and 3 cases of the long segment type. The different colorectal anastomosis methods were divided into 10 cases in the traditional group and 15 cases in the SIS group. There were no intraoperative complications, wound infections, or anastomotic fistula. Compared with the SIS group, children in the traditional group had an increased operative time (129.5 versus 103.00 minutes; P < .0001), increased intraoperative blood loss (20.00 versus 7.00 mL; P < .0001), increased postoperative hospitalization time (12.00 versus 9.00 days; P = .0003), and increased postoperative defecation time (18.40 versus 13.20 hours; P < .0001). After 6–12 months of follow-up, there was no anastomotic stenosis or enterocolitis in the SIS group. In the traditional group, 1 child had anastomotic stenosis, which improved 6 months after anal dilatation. One case of enterocolitis occurred 4 months after the operation and was cured after enema and infusion. Conclusion: Laparoscopic-assisted resection combined with colorectal anastomosis with the stapling technique in the treatment of HSCR in infants is feasible. It had a short operation time, less bleeding, less trauma, and a rapid recovery of postoperative intestinal function. The anastomosis was smooth, wide, and reliable, and anastomotic fistula and stenosis did not occur. [ABSTRACT FROM AUTHOR]

A 3D vacuum arc remelting model coupling heat transfer, fluid flow, solidification, nucleation, and grain growth is established. The effect of melting rate and current intensity on the solidification structure, depth of the molten pool, and equiaxed crystal rate is investigated by the simulation. Near the baseplate of the mold, the direction of columnar dendrites is vertically upward. Near the mold lateral wall, the columnar dendrites grow aslant upward. From the initial time to the end of the remelting period, the depth of the molten pool increases continuously and reaches the maximum value of 105.5 mm at the end of the remelting period. In the end feeding period, the depth of the molten pool decreases gradually until the molten pool solidifies completely. With the melting rate increasing from 0.8 to 2.4 kg min−1, the maximum depth of the molten pool increases from 84.6 to 130.3 mm and the equiaxed crystal rate is 42.5%, 57.2%, and 62.7%, respectively. With the current intensity increasing from 2 to 6 kA, the maximum depth of the molten pool increases from 63.1 to 92.9 mm and the equiaxed crystal rate decreases from 51.7% to 45.6%. [ABSTRACT FROM AUTHOR]

Bupivacaine (BUP) is a long-acting amide local anesthetic that may induce strong neurotoxicity and neurological complications. In this study, we elucidate the influence of microRNA-494-3p (miR-494-3p) in BUP-induced neurotoxicity in primary mouse hippocampal neuronal cells. In this study, primary hippocampal neurons were isolated from neonatal C57BL/6 mice. The isolated neurons were treated with various doses of BUP. MTT assay was conducted to analyze neuronal viability. Gene expression measurement was done by RT-qPCR. The impact of miR-494-3p in BUP-mediated neural injury was examined using TUNEL, flow cytometry, western blotting, and ROS activity detection. The regulatory relationship between miR-494-3p and cyclin-dependent kinases 4 and 6 (CDK6) was identified using a luciferase reporter assay. BUP treatment led to neurotoxicity and miR-494-3p upregulation in primary cultured hippocampal neurons. Functionally, miR-494-3p depletion alleviated neuronal apoptosis and oxidative damage induced by BUP. We verified that miR-494-3p targeted and negatively modulated CDK6. MiR-494-3p depletion also activated PI3K/AKT signaling by elevating CDK6 expression in BUP-treated neurons. Furthermore, CDK6 knockdown or PI3K/AKT inactivation attenuated the neuroprotective role of miR-494-3p depletion. Silencing miR-494-3p exerts neuroprotective function in hippocampal neuronal cells against BUP-induced injury by the CDK6-PI3K/AKT pathway. [ABSTRACT FROM AUTHOR]

With the high temperature confocal laser scanning microscope applied, the effect of cooling rate, temperature interval, and cooling mechanism on the solidification microstructure and primary carbide participation in GCr15 steel are investigated. The solute distribution in interdendritic segregation and participation carbide are analyzed by electron probe microanalysis. The results show that solute concentrate is low in the dendrite zone but it increases clearly in the segregation zone. The carbon concentration in the precipitation can reach 6.49%, which means the primary carbide is M3C. In the heating process, the segregation zone and carbide participation melt first before it reaches the solidus temperature. During the solidification stage, the microstructure is refined and the size of primary carbide is reduced with a higher cooling rate, but the number density of primary carbide is increased. Moreover, it is found that the microstructure is formed in the earlier solidification, before the temperature declines to 1673 K. While the primary carbide participates in the later cooling stage and the transition temperature for the primary carbide is 1503 K. In addition, the primary carbide size can be reduced with the cooling rate larger than 300 K min−1 in the subsequent cooling stage. [ABSTRACT FROM AUTHOR]

Here, a poly(vinylidene fluoride) (PVDF)-based composite polymer electrolyte (CPE) with a unique Li0.33La0.56TiO3 (LLTO) nanotube filler, which shows a high Li-ion conductivity, is reported. Compared with LLTO nanoparticles (NPs) and nanowires (NWs), the LLTO nanotube fillers increase the interfacial area between PVDF and the LLTO filler, leading to the simple transportation of Li-ions through these interfacial pathways. In addition, the Li plating and stripping cycling performance of the CPEs is improved to 205 h at 0.1 mA cm−2, and the performance of the Li‖CPEs‖LiFePO4 cells also achieves a discharge capacity of 120 mA h g−1 after 100 cycles at 0.5C at room temperature. These results demonstrate an effective interfacial strategy for the design of high Li-ion conduction CPEs for all solid-state batteries. [ABSTRACT FROM AUTHOR]

Image reconstruction of electrical capacitance tomography (ECT) is an ill-posed inverse problem. The simulated annealing (SA) algorithm is suitable for the solution of the ECT inverse problem. However, selection of related parameters of the SA algorithm will influence the reconstruction performance of ECT. We present an ECT image reconstruction method based on the adaptive simulated annealing (ASA) algorithm. We adopt the bat algorithm in the new solution generation strategy of the ASA algorithm. Moreover, the definition of the energy function introduces the sparsity of the reconstructed image. As a result, an adaptive annealing strategy is proposed to select the appropriate annealing rate. We made reconstructed image comparisons among linear back-projection, Landweber iteration, SA, and ASA algorithms via simulation and static experiment. Results show that improved reconstructed images can be obtained using the ASA algorithm. [ABSTRACT FROM AUTHOR]

A physical water model based on the similarity principle is established to investigate the fluid flow and mixing phenomena during the Ruhrstahl–Heraeus (RH) steel refining process. The velocity distribution and the turbulent features on the center section are obtained using particle image velocimetry (PIV) measurement. Two vortexes between the down‐leg snorkel and the ladle sidewall are observed. The effects of the number of gas‐injection nozzles and the liquid levels in the vacuum chamber on the fluid phenomena are performed. More injected nozzles and a higher liquid level in the vacuum chamber generate larger velocity in the ladle. Twenty monitors in the ladle are used to monitor the variation of the conductivity to obtain the mixing time, indicating that the mixing time varies much with locations. The distribution of the mixing time on the vertical center section of the ladle is obtained. Moreover, the relationship between the circulation rate and the mixing time is obtained, indicating that the mixing time decreases with increasing circulation rate, and the slope of their relationship is −0.35. [ABSTRACT FROM AUTHOR]

A three-dimensional computational model, coupled with the Large Eddy Simulation (LES) model and Volume of Fluid (VOF) multiphase model, was established to investigate the two-phase flow and slag entrainment during steel bloom continuous casting. The influence of the in-mold electromagnetic stirring (M-EMS), casting speed, and submerged entry nozzle (SEN) immersion depth on the flow pattern and slag entrainment were evaluated. The number, size, velocity, and spatial distribution of slag droplets were counted and the location, velocity and probability of the slag entrainment on the meniscus were exported in real time through a user defined function. The result shows that the slag entrainment mainly occurred around the 1/4 width of the mold. The equivalent diameter of most slag droplets was 2–6 mm under the current casting condition. A formula for the equivalent diameter distribution of slag droplets was proposed according to the statistical result. [Display omitted] • Transient two-phase flow and slag entrainment in steel bloom continuous casting. • Number, size, velocity, and spatial distribution of slag droplets. • Quantitative study on slag entrapment and liquid level fluctuation. • Location, velocity and probability of the slag entrainment on the meniscus. [ABSTRACT FROM AUTHOR]

Axial ultrasonic vibration-assisted cutting (AUVC) has been proved to have better machining performance compared with conventional cutting methods; however, the effect of numerous and complex influencing factors on machining performance has not been clearly revealed, and a recommended combination of cutting conditions has not been proposed yet, especially for difficult-to-machine material such as Ti6Al4V alloy. This paper focuses on the experimental and theoretical investigation into Ti6Al4V machining performance with AUVC method. First, a retrospective of the separation characteristics of AUVC is provided, and the variable parameter cutting characteristics are demonstrated. The influencing factors on machining performance are classified into four categories: machining parameters, vibration parameters, tool choice, and cooling conditions. The relationship between these factors in terms of their effect on machining performance is established theoretically. Then, it describes experiments to determine the influence of these factors on cutting force, tool life, and surface roughness. For absolute influence, the orders for cutting force, tool life, and surface roughness are respectively cutting depth > amplitude > feed rate > rotation speed, rotation speed > feed rate > amplitude > cutting depth, and feed rate > amplitude > cutting depth > rotation speed. However, for relative influence, the order is unified as amplitude > feed rate > rotation speed > cutting depth. Finally, it suggests a smaller feed rate, larger amplitude, moderate rotation speed, and smaller cutting depth in addition to a WC tool coated with TiAlN and used under HPC cooling condition for optimal performance of AUVC. This recommendation is based on the theoretical analysis and experimental results of cutting force, surface roughness, and tool life. [ABSTRACT FROM AUTHOR]

Diffusion couples of 3CaO·Al2O3 and Fe–S–O–(Al) alloys are prepared to investigate the transformation of calcium aluminate reacting with solid sulfur‐containing alloys. Diffusion behaviors and solid reaction between the alloy phase and the slag phase under 1373 K are studied. Product layers of 12CaO·7Al2O3 and CaS are formed at the interface. After heating for 10 h, the average thickness of CaS layer in samples with and without Al in the alloy phase is 2.10 and 0.71 μm, respectively, while it increases to 3.76 and 1.75 μm after 50 h heating. Aluminum in the alloy makes the solid reaction at the interface easier to happen, meanwhile inhibits the formation of CaS layer by promoting the formation of 12CaO·7Al2O3 layer and suppresses the diffusion of sulfur. [ABSTRACT FROM AUTHOR]

Objective: The present study determined the feasibility and initial efficacy of a kindergarten‐based, family‐involved intervention in improving children's hand hygiene (HH) behaviors. Design: A cluster‐randomized controlled trial was performed, with a cluster defined as a kindergarten class. Sample: Participants were recruited from 20 classes in six kindergartens. A total of 289 children and their families were enrolled in the intervention group, and 293 children and their families were enrolled in the control group. Measurements: HH behavior and a related knowledge survey, as well as data on absences due to infection, were collected. Intervention: An 8‐week training session on HH for children and an education program combining a seminar and WeChat groups for parents were provided to participants in the intervention group. Results: Two HH behaviors of children, namely, HH after playing outside and 7‐stage HH compliance, were significantly different between the two groups after the intervention. The two HH behaviors and knowledge of infections of parents/legal guardians in the intervention group were better than those in the control group after the intervention. The number of absences due to infections in children was lower in the intervention group than in the control group. Conclusions: Kindergarten‐based, family‐involved interventions effectively improved the HH behavior of kindergarten children and decreased absences due to infections. [ABSTRACT FROM AUTHOR]

Plain strain deformation is performed on solid steel samples at 1473 K and semi‐solid samples at 1743 K. The deformation of inclusions under the reductions of 10%, 20%, and 30% is studied. In the solid steel, the average aspect ratio of inclusions increases from 1.23 in the original slab to 2.07, 2.23, and 2.30 under the reduction of 10%, 20%, and 30%. The deformation of inclusions in the semi‐solid steel, which is much smaller than that in the solid steel, is hardly influenced by the reduction. Inclusion deformation is explained by the difference of hardness between the inclusion phase and the steel matrix. Though inclusions in steel samples deformed at 1473 K are a little harder than those in steel samples deformed at 1743 K due to the thicker CaS shell formed by the transformation of inclusion composition. Stress–strain curves indicate that the semi‐solid steel matrix at is much softer. In the semi‐solid steel at 1743 K, the soft steel matrix deforms more than inclusions, leading, in turn, to a smaller deformation of inclusions. [ABSTRACT FROM AUTHOR]

Transition-metal sulfides (TMSs) were demonstrated to be heartening anodes for sodium-ion batteries (SIBs) because of their alterable nanostructures, large theoretical capacity and environmental friendliness. Whereas, the relatively poor rate and cycling capability of TMSs still hinder the rapid development of their practical applications. Herein, a novel CuS nanocable self-assembled by hierarchical nanosheet is designed as SIB anodes, which delivers a large capacity (367 mAh g−1 at 5 A g−1), excellent rate capacity and cycle performance (213 mAh g−1 after 2000 cycles at 15 A g−1). The uniquely hierarchical nanostructure can both contribute more effective and durable active sites and shorter diffusion length of sodium ions/electrons. Besides, ex situ XRD, HRTEM and SAED reveal the phase transformation during sodiation process and the reaction mechanism of as-synthesized CuS nanocables. These results can offer new clues and inspirations to understand the relationship between the designed nanostructures and sodium storage behaviors of other TMSs. Synopsis: Hierarchical CuS nanocables constructed by self-assembled nanosheets provide high capacity, ultrafast and long-cycle life sodium storage properties. [Display omitted] • Unique CuS nanocables were controllably fabricated and facilely turned. • Self-assembly of hierarchical nanosheets was achieved on CuS nanocables. • Fabricated CuS nanocables exhibited excellent sodium storage performance. • Ultrafast ion transportation kinetics and long-cycle life could be achieved. [ABSTRACT FROM AUTHOR]

The solidification structure and macrosegregation are investigated in different current intensities of mold electromagnetic stirring (M‐EMS) and final electromagnetic stirring (F‐EMS) by a series of industrial trials during the 20CrMnTi bloom continuous casting (CC) process. With the current intensity of M‐EMS increasing from 100 to 390 A, the deflection angle of columnar dendrites increases from 25.0 to 32.49 deg. With the current intensity of M‐EMS increasing from 0 to 390 A, the equiaxed crystal ratio increases from 20.4% to 25.7% and center porosity varies little. With the increasing current intensity of M‐EMS, the negative segregation in the subsurface and positive segregation in the columnar‐to‐equiaxed transition (CET) zone deteriorate gradually. The M‐EMS has little effect on the center‐positive segregation, and the center‐positive segregation is maintained at 1.37–1.40. With the current intensity of F‐EMS increasing from 0 to 500 A, the equiaxed crystal ratio is within 25.3–25.8%, and the large center porosities disappear instead of numerous fine spots in the equiaxed zone. The degree of center‐positive segregation decreases from 1.48 to 1.30. For the CC process, to obtain a better internal quality of 20CrMnTi bloom, the optimal current intensities of M‐EMS and F‐EMS are 0 and 500 A, respectively. [ABSTRACT FROM AUTHOR]

Two types of inclusions in the stainless steels are detected: MnO·Cr2O3–MnS dual‐phase ones and pure MnS ones. The increase of sulfur content can inhibit the formation of MnO–Cr2O3–MnS inclusions and reduce the harm of MnO·Cr2O3–MnS inclusions on the pitting corrosion of stainless steels. When the sulfur content increases from 26 to 70 ppm, the average pitting potential increases from 0.34 to 0.4 VSCE due to the decrease in the number density of MnO–Cr2O3–MnS inclusions. A Cr‐depletion zone exists in the steel matrix around MnO–Cr2O3–MnS inclusions. The size of pits induced by MnO·Cr2O3–MnS inclusions is larger, which poses a more serious threat to the pitting resistance of stainless steels. [ABSTRACT FROM AUTHOR]

Herein, the fluid flow pattern in a continuous casting slab strand with varied degree of clogging of the submerged entry nozzle is measured using nail boards in industrial trials. The influence of clogging on meniscus velocity, top surface position, surface level fluctuation, and slag entrainment of the strand is investigated. The number density and area fraction of nonmetallic inclusions including Na2O and K2O‐bearing entrained slag ones within the subsurface of steel slabs are inspected using an automatic scanning electron microscope (SEM). The flow pattern in the strand periodically transforms from a double roll flow to a complex flow and/or a single roll flow. The fluid field in the continuous casting mold is unstable and asymmetric under the condition of varied degree of clogging with time. The variation of the meniscus velocity and the surface level fluctuation with time is stochastic. The percentage of >3 mm level fluctuation increases from 4.7% to 10.6% with a serious clogging of the submerged entry nozzle. The amount of entrained slag inclusions with serious clogging is approximately 1.6 times than that with slight clogging. In addition, slag entrainment mechanisms of the shear‐layer instability and the vortex formation are discussed. [ABSTRACT FROM AUTHOR]

Herein, plant trials are conducted to investigate the effect of slag modification on inclusions in Si–Mn‐killed 304 stainless steels. The slag basicity has a significant influence on inclusion compositions in 304 stainless steels. The Al2O3 content in inclusions shows a slight increase tendency with the slag basicity of 1.9. The addition of CaO increases the slag basicity from 1.9 to 2.2, which is beneficial to the removal of inclusions while increasing the Al2O3 content in inclusions from roughly 20% to 40%. The low slag basicity lowers the Al2O3 content in inclusions to around 20% while resulting in a higher total oxygen (TO) at the ladle furnace (LF) end. A kinetic model of slag–steel–inclusion reactions is developed to simulate the effect of slag modification on inclusion composition using FactSage Macro Processing. Evolutions of slag, steel, and inclusions during the slag modification process are well predicted. [ABSTRACT FROM AUTHOR]