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Despite the widespread application of mechanical waves in solidifying metals, the wave propagation laws in melt and the motion patterns of melts are unclear, which has seriously hindered the development of vibration solidification treatment. It is difficult to solve the wave propagation because of the spatial heterogeneity and the intrinsic viscoelasticity of solidifying metals. In this paper, a physico‐mathematical model is developed by coupling the unsteady temperature field and the integral Hooke–Kelvin model unifying various rheological models during solidification, and simplifies to wave equations by introducing memory factors. Then, the wave equations are solved by a staggered‐grid high‐order difference method. Subsequently, the propagation laws of mechanical waves in a large casting and a feeding channel during solidification are analyzed, eventually verified by casting experiments. It is shown that the viscoelasticity of solidifying metals is significant for the wave field. In the large casting, both displacements and stresses exhibit complex multi‐lobe patterns. In the feeding channel, the formation of micropores between the quasi‐liquid and the quasi‐solid phase and the feeding improvement by vibrations are well explained by simulation. The numerical model is a novel reliable method to theorize the solidification under vibration and expands the potential applications of vibration. [ABSTRACT FROM AUTHOR]

According to the design concept of hollow metallic microlattices, the quality of the coating has a considerable influence on the performance of the material. To avoid the effect of by-products in the coatings, we have chosen the Al-induced electroless plating method to respond to the composition design of this material. In this paper, the coatings formation process of Al-induced electroless plating on the metallic surface is systematically investigated. The coatings created by Al-induced electroless plating were characterized by surface morphology, XRD patterns, and electrochemical potential. Subsequently, the deposition process of elements on the metallic substrate was simulated by molecular dynamics. Finally, the surface morphology changes of coatings were observed at different plating times to verify the simulation results. The results indicate that the four kinds of coatings are each composed of a single metal element (copper, cobalt, nickel, and iron) with no by-products. Based on the results of morphology changes of the coatings and the deposition simulation, the overall formation process of Al-induced electroless plating is described. The deposition of coatings has the characteristics of preferential growth and aggregate growth. The metal atoms that are generated from the reaction of the reducing electrons with the target metallic ions in the solutions are deposited on the substrate surface as the primary cores. The reducing electrons are provided by the dissolution of Al foil. With the increase in the number of generated metal atoms, multiple atomic clusters form in the areas of the primary cores. These clusters develop at various scales on the substrate surface, forming irregular particles. Eventually, coatings are formed completely with uniform particle sizes. [ABSTRACT FROM AUTHOR]

The shrinkage defects of Al-Cu-Mn-Ti alloy seriously hinder its application in high-performance engineering. In this study, mechanical vibration was introduced to low-pressure sand casting (LPSC) by a waveguide rod to eliminate shrinkage defects and improve mechanical properties. Four LPSC castings were performed by changing the solidification conditions: 20 kPa solidification pressure without and with 14 Hz vibration and 40 kPa without and with 24 Hz (the natural frequency of a casting system) vibration. The shrinkage defects, microstructures, and mechanical tensile properties at room temperature and at 2 mm/min tensile rate were investigated. X-ray detections showed that applying vibration was more effective than increasing solidification pressure in improving solidification feeding, while the most effective method was applying both simultaneously, which eliminated the shrinkage defects and increased the density by 2.7%. Microstructures exhibited that the average size of primary α-Al grains were reduced by 29.5%; mechanical tests showed that the ultimate tensile strength and the elongation increased by 21.7% and 7.8%, respectively, by applying vibration and increasing the solidification pressure simultaneously, as compared to the casting with 20 kPa solidification pressure without vibration. Mechanical vibration was conducive to mass feeding by refining the primary grains, to interdendritic feeding by reducing the threshold pressure gradient, and to burst feeding by collapsing the barrier. [ABSTRACT FROM AUTHOR]

In this paper, the thermal diffusion behavior of Fe/Cu/Ni multilayer coatings was investigated by molecular dynamics. The results show that the Fe, Cu, and Ni elements can diffuse each other at 1250 K. Meanwhile, the intrinsic diffusion coefficients and interdiffusion coefficients of the Fe, Cu, and Ni were calculated. Besides, the diffusion mechanism for high melting-point elements of Fe and Ni at 1250 K was analyzed in the paper. According to the simulation result, the Fe and Ni lattices were disturbed by the active Cu particles. Fe and Ni particles at higher energies may move out of their original positions and migrate into the Cu lattice randomly. Thus, the Fe and Ni elements were involved in the thermal diffusion. This can be confirmed by the decrease of the peak and the disappearance of the secondary peak in the radial distribution function curves. However, the position of the curve peaks did not change. Thus, the lattice structure was still maintained during the whole diffusion process. The thermal diffusion of the three elements was carried out by particle substitution at the lattice positions. It was a solid phase diffusion process. Furthermore, there was a clear particle diffusion asymmetry at the original interface of the element. It was consistent with the diffusion asymmetry of diffusion-couple experiments. The primary reason for this diffusion asymmetry was the difference in the interaction potential of the three elements. This asymmetry was ultimately reflected in the intrinsic diffusion coefficient and the interdiffusion coefficient of each element. For the Feâ€"Cuâ€"Ni ternary system, the largest diffusion coefficient was copper and the smallest was iron at 1250 K. [ABSTRACT FROM AUTHOR]

The effect of P/S-wave on the solidification feeding and the mechanism of vibration promoting the solidification feeding in the low-pressure casting are discussed in the paper. The casting defects were analysed by X-ray non-destructive testing and the buoyancy method. It can be found that the compactness of casting is greatly improved by vibration. In the solidification feeding, according to vibration theory, P-wave will play a decisive role. When the transmission direction of P-wave is perpendicular to the feeding direction, it will lead to the alternation of dense-sparse state in the solidification system. When feeding is blocked, in the sparse state, the diameter of the feeding channel will increase, so that the pressure loss of feeding decreases. At the feeding end, the feeding pressure will make the solidification feeding again. On the contrary, vibration can't further promote the feeding in the dense state. [ABSTRACT FROM AUTHOR]

In this study, the effect of vibration on the interdendritic feeding of Al–5%Cu–0.4%Mn alloy was investigated using vibration casting experiments and physical simulation. The solidification characteristics of the zinc-oxide paste (used as a mold coating to prevent sand burn during casting) resulted in shrinkage and porosity defects. The experiments were designed to show that vibration can improve feeding and reduce defects. The aqueous solution of sodium carboxmethyl cellulose (CMC) with the same rheological characteristic of metal melt was used in the physical simulation. The seepage calculation model of semisolid fluid in porous media under vibration was established, and the finite difference method and dynamic mesh technique were used to solve the model numerically. The casting results show that vibration can improve the feeding capacity and reduce shrinkage defects of Al–5%Cu–0.4%Mn alloy in gravity sand casting. The physical simulation results show that mechanical vibration can change the blocked structure at the seepage entrance, improve the permeability of porous media and reduce the resistance of interdendritic feeding. Mechanical vibration with the smaller frequency combined with the larger exciting force, or the larger vibration frequency combined with the smaller exciting force, can promote the seepage flow. Meanwhile, the numerical simulation of one-dimensional semisolid fluid seepage reveals that vibration can form a wave field in the porous medium, which can reduce the adhesion force between fluid and the capillary wall and destroy the boundary layer of fluid, thus promoting the seepage velocity. [ABSTRACT FROM AUTHOR]

Introduction: Malnutrition during a critical window of development in a fetus or infant can result in abnormal cardiac remodeling and function. It is uncertain whether the contribution of these effects continues to impact the cardiac remodeling and function of adults over the course of several decades of growth. Our study examined the impact of early Chinese famine exposure on cardiac remodeling, left ventricular (LV) diastolic function, and LV systolic function in adults. Methods: Participants at high risk of cardiovascular disease from the China Patient-Centered Evaluative Assessment of Cardiac Events Million Persons Project (PEACE MPP) were enrolled. The famine in China lasted from 1959 to 1962. A total of three groups were formed based on the participants' birth dates: pre-famine group, famine exposure group, and post-famine group. Logistic regression and linear mixed models were used to explore the association between famine exposure and cardiac remodeling, LV diastolic function and LV systolic function in adults. Results: The study included 2,758 participants, the mean age was 57.05 years, 62.8% were female, 26.4% had LV hypertrophy (LVH), 59.6% had LV diastolic dysfunction (LVDD), and 10.5% had reduced global longitudinal strain (GLS). Compared to post-famine exposure, participants had independently increased risk of LVH in the famine exposure group (OR: 2.02, 95% CI: 1.60–2.56) and pre-famine exposure (OR: 1.36, 95% CI: 1.06–1.76). Compared to post-famine exposure, the risk of LVDD remarkably increased in the famine exposure group (OR: 3.04, 95% CI: 2.49–3.71) and pre-famine exposure group (OR: 1.87, 95% CI: 1.52–2.31). Famine exposure had no significant impact on GLS but was associated with a significant increase in LV ejection fraction (LVEF) and LV end-diastolic diameter (LVEDD). Significant interactions were observed between the effects of famine exposure and other clinical/sociodemographic variables (gender, systolic blood pressure [SBP] ≥140 mm Hg or not, high school or above or not, and annual income <50,000 RMB or not) on these outcomes. Conclusion: Exposure to famine, particularly during fetal and infant stages, increases the risk of LVH and LVDD in adults. However, the LV systolic function remains preserved. These impacts are more pronounced in females, individuals with SBP ≥140 mm Hg, those with low income, or those with high educational status. [ABSTRACT FROM AUTHOR]

A unified wave equation of mechanical wave propagation during solidification of an alloy was established and the numerical solution of the wave equation was obtained. A three-element model (KSLS) used to describe the stress–strain constitutive relation of the alloy in the mushy zone was established by the analysis of rheological characteristics of molten melt during solidification. Based on the KSLS model, we could describe the constitutive relation of the liquid alloy, a Maxwell medium, and of the solidified alloy, an elastic medium, by the various Lame coefficients. The wave propagation during solidification was identified by a unified wave equation coming from a unified integral constitutive equation, to adapt to a variety of viscoelastic media. The wave equations could be solved succinctly by introducing a "memory factor" and the staggered grid finite difference method. The analytical results demonstrated that the unified wave equation could be perfectly applied to the numerical simulation of wave propagation during solidification. The propagation of the P-wave in a one-dimensional alloy was simulated during solidification, obtaining the propagation law of the mechanical wave: the wave with variable wavelength and amplitude propagated with attenuation during solidification; otherwise, as the source excitation force was fixed, the fluctuations caused by the mechanical wave could be more serious when the vibration was applied in the melt directly, which is more conducive to grain refinement. [ABSTRACT FROM AUTHOR]

• The design method of HEA coatings in electroless plating was proposed. • The element types of the HEA coating are controlled by the deposition composition. • The element proportions of the coating are controlled by the deposition thickness. • The changes of multilayer coatings during thermal diffusion were studied. • The corrosion resistance of alloy coating is better than metal coating. In the paper, the preparation process for high-entropy alloy coatings in the field of electroless plating was explored. According to the method for designable alloy coatings, Al-induced electroless plating was used to create multilayer coatings. The thermal diffusion process was used to alloy the multilayer coatings. Therefore, multilayer coatings as a predesigned basic material for alloy coatings needed to be discussed first. Then, the alloying process of high-entropy alloy coatings was primarily investigated. In this paper, the CuCoNi alloy coating was the main object of research. The alloying process was characterised and analysed by scanning electron microscopy and X-ray diffraction. The corrosion resistance of the coating was measured by electrochemical tests. The results show that the element distribution and the phase peaks of the multilayer coatings gradually became homogeneous and stable during thermal diffusion. The alloying process was confirmed by these changes in morphology and structure. Alloy coatings were created with controlled element types and element proportions in electroless plating. The element types of the coatings can be controlled by the deposition composition, and the element proportions can be controlled by the deposition thickness. The corrosion resistance of the alloy coating was better than that of the single-element coating. At 6 h of thermal diffusion (which is the optimum diffusion time for the CuCoNi alloy coating), the corrosion potential was − 0.218 V, and the corrosion current density was 2.72 μA/cm2. Based on the preparation process results, the design methods for high-entropy alloy coatings were proposed. [ABSTRACT FROM AUTHOR]

In order to overcome the zigzag grids generated by conventional finite difference method on complicated casting boundaries in the simulation of casting process, the generation program for 2-D boundary fitted coordinate grid has been developed by solving a set of partial differential equations (PDE) numerically. The STL format files were treated as input data for 2-D physical regions. The equipartition method for boundary points was used to improve the self-adaptability of grid according to the characteristic of the STL format files. The program was demonstrated through some examples. The comparison between the conventional finite difference method and the proposed method shows that this program is effective and flexible for generation of boundary-fitted grid in any arbitrary 2-D complex domain, and the grid is in accordance with the variety of boundary curvature finely. The program also provides two types of boundary-fitted grids for double-connected region, O-type and C-type. The limitation of the step-like boundary with the rectangle grid could be avoided effectively. Therefore, the computational accuracy and efficiency would be improved and the computational time would be saved significantly by the application of boundary-fitted grids. [ABSTRACT FROM AUTHOR]

Abstract: Mg–Zn–Y quasicrystal alloy (QA) particles reinforced composite was prepared using an adscititious method, and characterized using scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and tensile testing technique at room temperature. Experimental results indicate that α-Mg columnar dendrite gradually becomes fine equiaxed dendrite and ellipsoidal cellular dendrite as more Mg–Zn–Y QA particles are added into the matrix alloy. Thread-like Mg24(Gd,Y)5 phases and rod-like Mg5(Gd,Y) phases are replaced by lamellar Mg24(Zn,Gd,Y)5 compounds and granule Mg3Zn6(Y,Gd) quasicrystal I-phases. The ultimate tensile strength and yield strength of the composite increase by about 45MPa and 20MPa respectively when the amount of QA particles added increases from 3% to 15%. It can therefore be concluded that the microstructure and mechanical properties of Mg–8Gd–3Y alloy can be improved by adding QA particles. [Copyright &y& Elsevier]

Cu catalyst often subjects to low stability due to chemical state transformation during carbon-oxygen hydrogenation reaction. In the present work, the copper catalysts embedded in N-doped carbon microsphere (Cu@NC) were fabricated by one-pot hydrothermal method and applied in dimethyl oxalate (DMO) hydrogenation to methyl glycolate (MG). The optimized Cu@10NC catalyst exhibited an excellent stability with DMO conversion of 80.1% and MG selectivity of 80.3% during 220 h long-term evaluation under 1.9 MPa, 210 °C, H 2 /DMO molar ratio of 80 and WHSV of 0.8 g DMO ·g Cu −1·h−1, beneficial from the stable Cu+ ratio and confinement effect of carbon support during the reaction. The Cu dispersion and Cu+ proportion can be finely controlled by varying the N-doping content due to the enhanced interaction between Cu and carbon microspheres. Particularly, graphitic-N is primarily accountable for Cu dispersion, while pyridinic-N is dominantly responsible for the stabilization of Cu+ species. [Display omitted] • Cu embedded in N-doped carbon microsphere (Cu@NC) was successfully constructed. • Cu@10NC catalyst exhibited excellent stability during 220 h long-term evaluation. • Graphitic-N is primarily accountable for improving Cu dispersion. • Pyridinic-N is dominantly responsible for the stabilization of Cu+ species. [ABSTRACT FROM AUTHOR]

In January 2018, gerbera plants showed root rot symptoms were found in a greenhouse at Guizhou Horticultural Institute in Guiyang city, Guizhou Province in southwest China. Morphological and molecular identifications confirmed the isolation of Fusarium proliferatum. The pathogenicity was verified with Koch's postulates. To our knowledge, this is the first report confirming root rot of gerbera caused by Fusarium proliferatum in China. [ABSTRACT FROM AUTHOR]

In this study, the geometric features of ZL205A alloy castings as well as the formation mechanism of hot tearing under the low-pressure casting process were investigated. To explore the effects of geometric features and the low-pressure casting process on the envelope density and stresses of the ZL205A alloy cylindrical components, pouring experiments were performed, and the solidification process was simulated using the commercial software ProCAST. The results demonstrate that, among the castings with various geometric cross sections, those with round features are most considerably hindered. The experimental results show that hot tearing occurs in the castings when the hindrance factor ε = 0.129 or δ:R = 1:15 at the outside radius of R = 150 mm of the cylindrical components. The simulation results reveal that the position of hot tearing formed in the cylindrical casting is (0.44~0.48)h heights, (0~0.2)δ thickness for a cylindrical envelope with a low-pressure casting process. The combination of copper-rich, hindered stresses and welding stresses causes hot tearing in cylindrical castings. [ABSTRACT FROM AUTHOR]

The genetic basis underlying loss‐of‐virulence mutations that arise among natural phytopathogen populations is not well documented. In this study, we examined the virulence of 377 isolates of Pseudomonas syringae pv. actinidiae biovar 3 (Psa3) that were isolated from 76 kiwifruit orchards suffering from bacterial canker disease. Eighty‐four nonpathogenic isolates were identified in 40 orchards. A nonpathogenic isolate G166 was found to be defective in hrpL transcription and the downstream type III secretion system (T3SS)‐dependent phenotypes. Comparative genomics and complementary expression assay revealed that a single‐base "G" insertion in the hrpL promoter blocks gene transcription by reducing promoter activity. The electrophoretic mobility shift assay showed that the genetic variation impairs σ54/promoter binding during gene transcription under hrp‐inducing conditions, resulting in lower expression of hrpL. A PCR‐restriction fragment length polymorphism assay was performed to trace the evolutionary history of this mutation, which revealed the independent onset of genetic variations in natural Psa3 populations. We also found that nonpathogenic variants outperformed virulent Psa3 bacteria for both epiphytic and apoplast colonization of kiwifruit leaves in mixed inoculations. Our study highlights a novel mechanism for loss of virulence in Psa3 and provides insight into bacterial adaptive evolution under natural settings. [ABSTRACT FROM AUTHOR]

TiV-based alloys present desirable hydrogen storage properties owing to the formation of Body-centered cubic (BCC) solid solutions. However, the nanostructure that helps hydrogen absorption and desorption is hard to be designed and prepared in these alloys. In this study, Ti 40 Zr 60- x V x (x = 20, 25, 30) alloys with hyperfine nano-eutectic structures of 50–500 nm in lamellar space are prepared, and the nano-eutectic structures can be refined by increasing Zr content. Ti 40 Zr 60- x V x alloy powder exhibits excellent activation and hydrogenation properties. The phase separation and nano-eutectic structure are formed due to the differences of atomic size in Ti 40 Zr 60- x V x alloys. The highest total hydrogenation capacity of 2.4 wt% is obtained within 10 min at 200 °C under 1 MPa H 2 by Ti 40 V 35 Zr 25 alloy, surpassing that of Ti 40 Zr 40 V 20 and Ti 40 Zr 30 V 30 alloys of 2.2 wt% in 20min. Based on the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model, lower energy is required for the hydrogenation of Ti 40 V 35 Zr 25 alloy. Due to the formation of some stable hydrides, the Ti 40 Zr 60- x V x alloys show lower reversible hydrogenation capacities. The spinodal decomposition in Ti 40 V 35 Zr 25 alloy facilitates the formation of reticular eutectics, which provide high-density phase interfaces and produce "synergistic effect". As a result, the hydrogenation kinetic and capacity are enhanced significantly. • Large atomic size differences of the Ti 40 Zr 60- x V x promote nano-eutectic structure. • Novel Ti 40 V 35 Zr 25 alloy form hyperfine nano-eutectic with lamellar space of 50–500 nm and spinodal decomposition structures. • The capacity of 2.4 wt% at 200 °C/1 MPa within 10 min is achieved by Ti 40 V 35 Zr 25 alloy. • The spinodal decomposition promote formation of eutectic phases with excellent hydrogenation absorption property. [ABSTRACT FROM AUTHOR]

In this work, two kinds of YSZ nano powders were used as the raw materials to prepare thermal barrier coatings (TBC) via atmospheric plasma spraying. Firstly, raw materials with different original morphologies constitute feedstocks with varying internal structures. Secondly, these feedstocks, after spraying, form TBCs with different structures and porosity. Based on this, the differences in the morphologies of the raw materials may result in variations in the performance of the coatings. Therefore, the high-temperature performance of the corresponding TBCs was assessed comprehensively. Notably, the TBC prepared from flaky-YSZ (FYSZ) nano raw materials exhibited failure after only 84 thermal shock cycles, while the TBC prepared from granular-YSZ (GYSZ) nano raw materials maintained functionality even after 100 thermal shock cycles. Meanwhile, the GYSZ TBC demonstrates a better resistance to high-temperature oxidation with slower TGO growth. The failure mechanism of the TBCs was analyzed, focusing on the morphologies and structural characteristics. The findings highlight that disparities in raw materials' morphologies play a pivotal role in regulating the high-temperature service performance of the TBCs. The GYSZ raw materials are conducive to the formation of denser feedstocks, leading to decreased porosity in the coatings. In addition, their small size and uniform particle distribution facilitate the formation of columnar grains in the coating, enhancing the interlayer bonding strength of the GYSZ TBC. Consequently, during high-temperature service, the GYSZ TBC can effectively impede the growth of the thermally grown oxide (TGO) and alleviate the associated thermal mismatch stress, thereby ensuring a prolonged service life of the TBC. This work establishes a theoretical foundation for designing the performance of TBCs based on modulating the morphologies of raw materials. The raw material morphology's impact on high-temperature oxidation resistance and thermal shock resistance of APS 8YSZ TBCs was firstly studied. The granular YSZ (GYSZ) TBC with nanostructure shows better thermal shock and oxidation resistance at high temperature. The GYSZ nano materials promote dense feedstocks formation better, which cause lower TBC porosity, slowing TGO growth, aiding durability. Besides, GYSZ feedstocks promote continuous columnar grains and compact splat interfaces in TBCs. [Display omitted] • Morphology impact of raw material on 8YSZ TBCs at high temperature was first studied. • Granular YSZ (GYSZ) nano materials promote dense feedstocks formation better. • GYSZ feedstocks cause lower TBC porosity, slowing TGO growth, aiding durability. • GYSZ feedstocks promote continuous columnar grains and compact splat interfaces in TBCs. • GYSZ TBC shows better thermal shock and oxidation resistance at high temperature. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, melt hydrogenation, which is a new hydrogen treatment method, was used to hydrogenate Ti600 alloy, the relationship between the hydrogen partial pressure and the hydrogen content was built by analyzing experimental data, and microstructure was observed and mechanical properties was tested. It was found that hydrogen addition made the thickness of the solidified shell thinner and a big temperature gradient existed from the top to bottom surface of the alloy melt. With increasing hydrogen partial pressure, the directional solidification structure can be formed in the Ti600 alloy ingots. Microstructure of Ti600 alloy was modified significantly and the amount of α′ and β phases after melt hydrogenation. When increasing the content of hydrogen to 7.2 at.%, γ hydride was obtained in Ti600 alloy. The flow stress and yield stress decrease with increasing the hydrogen content. [Copyright &y& Elsevier]

In ZL205A alloy fully enveloped castings, linear segregation has been observed to be a common fault that can cause significant harm to the mechanical properties of the castings. Numerical simulation and similar molding approaches were used to obtain fully enveloped low-pressure castings of ZL205A alloy with linear segregation. Using energy dispersive spectroscopy and scanning electron microscopy, the microstructure of the alloy was examined with the goal to look into the formation mechanism of linear segregation. Results show that when the pressurization pressure P3 = 2P2, the hindered factor ε = 0.129, and the sand core is a phenolic resin sand core, linear segregation takes place in fully enveloped low-pressure castings. In addition, the hindered factor of fully enveloped castings is related to the collapsibility of the sand core, the easier the sand core collapses, the higher the hindered factor. There is a significant risk of hot tearing in localized castings connected to the slit gating system. Melt with a high concentration of Cu in the slit gating to feed hot tearing under pressurization pressure. Linear segregation is formed, and the segregation phase is Al2Cu. [ABSTRACT FROM AUTHOR]

The present study develops machine learning-based surrogate models for similarity criterion for solidification. The solidification rate R and Niyama criterion value from the simulation results are compiled, pre-processed, and then used to train the models. A regularization approach is used to minimize variance and avoid overfitting, with the base learners as three-layer artificial neural network (ANN). The predictions from the surrogate model are compared to the training data across both the solidification rate R and Niyama criterion value, considering the different factors affecting the solidification of castings. The trained model has a mean percentage error in the solidification rate R and Niyama criterion value of ~9.89% and ~1.90%, respectively, for the entire dataset. The results show that the predicted and training values are consistent with the parameter changes during the solidification of the castings. Factors affecting the solidification process of castings were evaluated. It is found that the casting temperature has the greatest influence on the solidification of castings, and the validity of the surrogate model is verified by pouring. [ABSTRACT FROM AUTHOR]

To investigate the strengthening and deformation behavior of heterogeneous dual-phase high-entropy alloys (HEAs), Al x CoCrFeNi 3 (x = 1, 1.1, 1.15, 1.2, 1.25 and 1.3) HEAs were designed and prepared. The microstructure consists of FCC phase rich in Co-Cr-Fe-Ni and BCC phase rich in Ni Al, forming a soft and hard heterostructure. With the increase of Al, the microstructure changes from hypoeutectic to hypereutectic, and Al 1.25 CoCrFeNi 3 alloy exhibits a fine eutectic lamellar morphology. Tensile results show that the strength of Al x CoCrFeNi 3 HEAs tends to increase and then decrease with increasing Al elements. Al 1.25 CoCrFeNi 3 alloy achieves the highest yield strength (535.32 MPa) and tensile strength (1060.59 MPa) as well as high plasticity (17.21%), achieving a balance of strength and plasticity. Interfacial strengthening, grain boundary strengthening, solid solution strengthening and friction stress strengthening play an important role. During the tensile process, the eutectic lamellar heterostructure results in long-range back stress, which induces the high strain hardening ability of FCC phase. Due to the continuous transformation of stress in lamellar heterostructure, the cracks initiate in BCC phase and passivate in FCC phase, which forms synergistic strengthening effects. • By adjusting the content of Al, a heterogeneous structure of eutectic high-entropy alloy was prepared. • The contributions of different strengthening mechanisms were calculated. • The deformation and fracture mechanisms were analyzed by a combination of theoretical analysis and experiment. [ABSTRACT FROM AUTHOR]

A series of Zn:In:Fe:LiNbO3 crystals were prepared by Czochralski method. The crystal composition and defect structure were analyzed by ICPOEMS, UV–vis and IR spectroscopy. The results show that with increasing In3doping concentration in melt, the segregation coefficients of both Zn and In ions decrease. The optical damage resistance of Zn:In:Fe:LiNbO3 crystals was studied by the transmitted beam pattern distortion method. It is found that the optical damage resistance of Zn:In3mol:Fe LiNbO3 crystals is two orders of magnitude higher than that of Zn:Fe:LiNbO3. © 2009 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim [ABSTRACT FROM AUTHOR]

In order to improve the castings quality of nickel-based superalloy in investment casting process, especially to reduce the shrinkage porosity, the processing parameters were optimized by numerical simulation and Taguchi method. The effects of processing parameters, such as pouring temperature, pouring time and mold shell preheating temperature, on the shrinkage porosity in the turbine nozzle investment castings prepared by K477 nickel-based superalloy were investigated. The results show that the effects of the mold shell preheating temperature, pouring temperature and pouring time are main influencing factors in turn, which are verified by the evaluation of signal-to-noise ratio and the analysis of variance. Further, based on the processing optimization, a K477 alloy turbine nozzle without shrinkage porosity was prepared with the optimized parameters: pouring temperature of 1450 ∘ C , mold shell preheating temperature of 1050 ∘ C and pouring time of 14 s, respectively. [ABSTRACT FROM AUTHOR]

A catalytic non-carbon composite composed of molybdenum disulfide (MoS 2) and conducting Magnéli phase Ti 4 O 7 is firstly synthesized by a facile hydrothermal method. The MoS 2 /Ti 4 O 7 composite catalyst shows significantly improved hydrogen evolution reaction (HER) activity in 0.5 M H 2 SO 4 especially at high overpotentials mainly due to the fast electron transfer ability caused by the newly formed interfacial S–O–Ti bonds and the enhanced electrochemical surface area. Tafel slope of the optimized MoS 2 /Ti 4 O 7 catalyst is as low as 48 mV · dec−1. It also presents an impressive stability with smaller activity degradation (5 mV potential shift at 10 mA cm−2) after 1000 cycles of cyclic voltammetry (CV) scanning. This is the first exploration on HER performances of MoS 2 and conductive metal oxide composite electrocatalysts, shedding light on the research of non-noble metal (sulphide)-metal oxide interface in energy catalysis significantly crucial for the development of cost-effective and stable HER electrocatalysts and even other electrocatalytic materials. Image 1 [ABSTRACT FROM AUTHOR]

The shipping industry is under significant pressure to reduce carbon emissions, and it is crucial to ensure that current efforts to reduce sulphur dioxide (SO 2) emissions do not result in increased carbon dioxide (CO 2) emissions. Against the background of carbon neutrality and sulphur emission control area (SECA) policies, this paper proposes a two-phase mathematical model to study the impact of liner low-sulphur compliance operation on carbon emissions. The model addresses four key problems: fleet deployment (phase Ⅰ); compliance option decisions, speed optimization and cargo allocation (phase Ⅱ). To solve these problems, a novel dual population evolutionary algorithm has been designed. The results show that implementing low-sulphur compliance operations for liner companies does not simultaneously reduce both total costs and CO 2 emissions, and the rise in the price of low-sulphur oil, the preference for cost decision-making and the expansion of SECAs will increase CO 2 emissions; the current sulphur limit policy needs to be adjusted urgently to implement the carbon neutrality goal of the shipping industry; government subsidies can reduce CO 2 emissions to some extent, but low-carbon or zero-carbon alternative energy is an inevitable choice for achieving carbon neutrality in the shipping industry. • Low-sulphur compliance operation cannot simultaneously reduce total costs and CO 2 emissions. • The scrubber option is more favorable than the fuel switching option. • Ships must rely on low-carbon or zero-carbon fuels to achieve carbon neutrality. • Switching to lower sulphur fuels results in higher Attained EEXI values. [ABSTRACT FROM AUTHOR]

The shipping industry is under significant pressure to reduce carbon emissions, and it is crucial to ensure that current efforts to reduce sulphur dioxide (SO 2) emissions do not result in increased carbon dioxide (CO 2) emissions. Against the background of carbon neutrality and sulphur emission control area (SECA) policies, this paper proposes a two-phase mathematical model to study the impact of liner low-sulphur compliance operation on carbon emissions. The model addresses four key problems: fleet deployment (phase Ⅰ); compliance option decisions, speed optimization and cargo allocation (phase Ⅱ). To solve these problems, a novel dual population evolutionary algorithm has been designed. The results show that implementing low-sulphur compliance operations for liner companies does not simultaneously reduce both total costs and CO 2 emissions, and the rise in the price of low-sulphur oil, the preference for cost decision-making and the expansion of SECAs will increase CO 2 emissions; the current sulphur limit policy needs to be adjusted urgently to implement the carbon neutrality goal of the shipping industry; government subsidies can reduce CO 2 emissions to some extent, but low-carbon or zero-carbon alternative energy is an inevitable choice for achieving carbon neutrality in the shipping industry. • Low-sulphur compliance operation cannot simultaneously reduce total costs and CO 2 emissions. • The scrubber option is more favorable than the fuel switching option. • Ships must rely on low-carbon or zero-carbon fuels to achieve carbon neutrality. • Switching to lower sulphur fuels results in higher Attained EEXI values. [ABSTRACT FROM AUTHOR]

Highlights • JinYin Hua is the most common ingredient for formulations and indigenous beverages. • Four novel and eleven known bioactive flavonoids were isolated. • All isolated flavonoids showed anti-hepatoma activity in SMCC 7721 cell. • Novel flavonoid 12 also showed significant hepatoprotective activity in vitro. • The isolated flavonoids could serve as nuclei for hepatic related diseases. Abstract Lonicera japonica , a widely used traditional Chinese medicine, possessed antiviral, hepatoprotective, anti-tumor and other activities. Meanwhile, L. japonica could be used as healthy food, cosmetics, and so on. Herein, four novel flavonoids, japoflavone A–D (2 - 3 , 5 , 12), together with ten known flavonoids, were isolated and identified on the basis of spectroscopic evidence from L. japonica. In addition, all isolates were assayed for their anti-hepatoma and hepatoprotective activities in vitro. 5 and 8 showed significant anti-hepatoma activity in SMCC 7721 cell with IC 50 values of 13.01 ± 2.62 and 16.69 ± 0.35 μg/ml; Compound 12 showed significant hepatoprotective activity against H 2 O 2 -induced injury in SMCC 7721 and HepG 2 cells (p < 0.001). Drop in the levels of catalase and superoxide dismutase caused by H 2 O 2 were remarkably reversed in a dose-dependent manner after treatment with 12. This study provided a phytochemical evidence for further development and utilization of Lonicera japonica in health products. [ABSTRACT FROM AUTHOR]

Ti44Al6Nb1Cr (at%) alloys with different lamellar spacing were prepared by cold crucible directional solidification. Creep tests were conducted at 750 °C under 260 and 300 MPa, and the microstructure before and after creep testing were observed and analyzed. The results show that the prepared TiAl alloys have similar macro / microstructure except for lamellar spacing, which are different from the heat-treated TiAl alloys with obviously changed macro/microstructure. The refinement of lamellar spacing can improve creep properties, especially the steady-state of fine lamellar alloy lasted for more than 600 h with creep rate at 7.3 × 10 −9 S −1 . The improvement of creep properties by refined lamellar spacing are revealed as following two reasons. (1) Fine lamellar spacing improves the stability of γ lamellae and increases the resistance for dislocation slip in γ lamellae. (2) It disperses stress concentration and delays the formation of globular structure at colony boundary. Moreover, the alternating β and γ laths in α-segregation zone can improve microstructural stability during creep. In β-solidifying γ-TiAl alloy, the local stress concentration on β-segregation at colony boundary promotes colony boundary sliding and the formation of void with globular structure, which further accelerates the creep failure. [ABSTRACT FROM AUTHOR]

[Objective] The paper was to explore the optimum dosage and application pattern of Trichoderma harzianum for controlling Potato Verticillium wilt. [Method] Two trials, sowing seed tubers in bacterial manure, sowing seed tubers in bacterial manure + root irrigation after seedling emergence, were conducted in the paper. [Result] T. harzianum could effectively control potato early dying and promote potato growth, thereby increasing potato yield. The control effects of sowing tuber in 300 times of bacterial manure + root irrigation with 300 times of conidia suspension after seedling emergence were ideal; the highest control effect and the highest saved yield loss were 72.60% and 33.33% , respectively. [Conclusion] The paper provides reference for field application of T. harzianum. [ABSTRACT FROM AUTHOR]

Abstract: A phase-field model whose free energy of the solidification system is derived from Calphad thermodynamic modeling of phase diagram is used to simulate structure evolution of Ti55Al45 alloy during directional solidification at growth velocities sufficiently higher than the critical velocity of transition from cells to dendrites, but lower than the absolute stability. The liquid–solid phase transition of L→L+β(Ti) is chosen. Firstly, the dynamics of the breakdown of initially planar interfaces into cellular structures then cellular dendrites are shown. Then the transition from cellular dendrites to fine cellular structures are shown at higher growth velocities. The solute segregation patterns are investigated at different growth velocities. The appearance of solute trapping is also investigated by determining the solute partition coefficients as a function of growth velocities. Agreement is reached with the theory of rapid directional solidification. [Copyright &y& Elsevier]