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In this work, Cu-doped O3-Na[Fe1/3Ni1/3Mn1/3]1-xCuxO2 cathodes were studied to enhance the structure stability and air stability. XPS analysis reveals that Cu-doping changes the electronic structure of Mn, thus enhancing the electrochemical performance of the NFM. The Cu-doped O3-Na[Fe1/3Ni1/3Mn1/3]0.95Cu0.05O2 (NFMC-0.05) cathode remains a capacity of 81.6 mAh g−1 at 10 C and keeps a capacity retention of 80.7% after 200 cycles at 0.5 C, while the undoped O3-NaFe1/3Ni1/3Mn1/3O2 (NFM) can only remain a capacity of 59.9 mAh g−1 at 10 C and keep a capacity retention of 68.9% after 200 cycles at 0.5 C. The 9-day air-exposed NFMC-0.05 exhibits a higher capacity of 97.3 mAh g−1 than the 9-day air-exposed NFM (58 mAh g−1) at 0.1 C, showing greatly enhanced air stability. Moreover, Cu-doping reduces the Rct value and the polarization, leading to a significant improvement in electronic conductivity. These results confirm that a small quantity (5 at. %) of Cu-doping improves the structural stability and air stability of the material, leading to the excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

In this paper, the microstructure and mechanical properties of Al-6.5Si-5.5Cu-0.2Zr-0.01Sr-0.06Ti-0.2Ce cast aluminum alloys were investigated in multistage solid solution systems. The microstructure of the alloy was characterized using an optical microscope (OM), scanning electron microscope (SEM), energy-dispersive spectrometer (EDS), x-ray diffraction (XRD) and transmission electron microscope (TEM), respectively. The hardness and conductivity of the alloy were measured using a Vickers hardness and eddy current conductivity testers, respectively, and the tensile properties were described by a drawing machine. The results showed that the mechanical properties of the alloy are the worst under the four-stage solid solution system (G1). With the increase in multistage solution temperature and holding time, θ phase (Al2Cu) was gradually dissolved into α-Al matrix to enhance the effect of dislocation strengthening. When the solution temperature reached 510 °C, the mechanical properties of the alloy were the best, and the tensile strength and elongation were increased to 354.90 MPa and 9.02%, respectively. With the increase in temperature, eutectic Si agglomeration and large area of insoluble phase between metals were found, resulting in the decrease in mechanical properties. [ABSTRACT FROM AUTHOR]

The effects of rare earth elements (Ce and Y) additions with the same content (0.3 wt.%, mass fraction) on microstructure evolution and mechanical properties of the Al-11.0Zn-3.1Mg-1.22Cu-0.1Sr-0.2Zr-0.1Ti alloy (base alloy) were investigated. The addition of Ce and Y refined the grain size and led to aging precipitates, which were dominated by the fine and compactly distributed GP (Guinier Preston) zones and the formed η′ (MgZn2) phase, improving the tensile properties of the alloy. The Ce-containing alloy possessed the highest tensile strength and elongation of 768.5 MPa and 8.0%, respectively. Meanwhile, the large atomic radius and low electronegativity of Ce and Y led to the discontinuous distribution of grain boundary precipitates (GBPs) and the broadening of the precipitate-free zones (PFZs) in the alloys, resulting in the improvement of intergranular corrosion resistance (IGC) of the rare earth modified alloys compared with the base alloy, with the best results for the Y-containing alloys. [ABSTRACT FROM AUTHOR]

A key force behind promoting green economic recovery is the digital economy. Examining how the digital economy supports societal development, technological advancement, and environmental improvement is worthwhile. This study examines the correlation between the growth of the digital economy, the modernization of the economic framework, and green total factor productivity (GTFP) using data from 276 Chinese cities from 2012 to 2018. To achieve this, the study utilizes Tobit regression and quantile regression models. Efficiency index approaches are used in the empirical examination for calculating green total factor productivity (GTFP). Although there are apparent regional variances, China's GDP might grow significantly due to the digital economy. The gross domestic product of the city's digital industry is larger than the higher GTFP, which accounts for its growth. On a more comprehensive and dynamic level, the electronic economy has favorably impacted China's GDP share percentage. A medium-range distribution system for the digital economy that supports GTFP is modernizing industrial infrastructure. This essay promotes green economic recovery and environmental conservation. [ABSTRACT FROM AUTHOR]

The microstructure and compressive properties of the 7xxx series aluminum alloy (Al – 12.44Zn – 3.22Mg – 1.13Cu – 0.19Zr – 0.12Sr) reinforced with SiC whiskers via squeeze casting are investigated after aging treatments T6-1, T6-2, T6I4-1, and T6I4-2. For this purpose, the effect of four kinds of aging heat treatments on the properties of the aluminum metal matrix composites (AMMCs) is studied systematically through Vickers hardness and room temperature compressive testing. The microstructure is analyzed by optical microscopy, scanning electron microscopy, and x-ray diffraction. The experimental results show that the hardness of the AMMCs after four kinds of aging processes has different degrees of improvement compared to no-aging. After the T6-1, T6-2, T6I4-1, and T6I4-2 aging processes, the hardness of the composites is 325, 278, 306, and 345.8 HV, respectively. The additional T6-2 aging treatment provides the highest compressive strength and compressive strain, about 747 MPa and 7%, respectively, as well as a maximum dislocation strengthening of approximately 86.89 MPa. [ABSTRACT FROM AUTHOR]

The performance of solid solution aging treatment on aluminum matrix composites prepared by powder metallurgy and reinforced with 6061 aluminum alloy powder as matrix; meanwhile, nano silicon carbide particles (nm SiCp), submicron silicon carbide particles (1 µm SiCp) and Ti particles were studied. The Al/SiCp composite powder was prepared by high-energy ball milling, and then cold-pressed, sintered, hot-extruded, and then heat-treated with different solution temperatures and aging times for the extruded composites. Optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy (EDS), X-ray diffractometer (XRD) and extrusion testing were used to analyze and test the microstructure and mechanical properties of aluminum matrix composites. The results show that after the multi-stage solid solution at 530 °C×2 h+535 °C×2 h+540 °C×2 h, the particles are mainly equiaxed grains and uniformly distributed. There is no reinforcement agglomeration, and the surface is dense and the insoluble phase is basically dissolved. In the matrix, the strengthening effect is good, and the hardness and compressive strength are 179.43 HV and 680.42 MPa, respectively. Under this solution process, when the aluminum matrix composites are aged at 170 °C for 10 h, the hardness and compressive strength can reach their peaks and increase to 195.82 HV and 721.48 MPa, respectively. [ABSTRACT FROM AUTHOR]

The 2124Ti aluminum alloy powder was self-designed and fabricated as the matrix, with micro-B4Cp and nano-SiCp adding a certain amount of Ti as the reinforcement, and the 10% B4Cp–2% SiCp/2124Ti composite material was prepared by powder metallurgy. The effects of three multistage solid solutions (G1: 480°C × 2 h + 490°C × 2 h, G2: 480°C × 2 h + 490°C × 2 h + 500°C × 2 h and G3: 480°C × 2 h + 490°C × 2 h + 500°C × 2 h + 510°C × 2 h) on the organization and properties of the 10% B4Cp–2% SiCp/2124Ti composite were investigated, and the optimal aging time of the material was explored after the solid solution. The results show that the G3 solid solution process had the best effect on improving the material performance. With the increase of solid solution temperature and the increase of solid solution time, the hardness of composite material increased significantly after solid dissolution. After 12h of 185°C aging, the hardness reached the peak, which increased by 23.6~50.6 HV compared with the hardness before the solid solution. With the increase of solid dissolution degree, the material conductivity decreased. Moreover, the compressive strength of the composite material was greatly improved after three solid solutions and 12h of aging, which was 690, 750 and 765 MPa namely, but the toughness of the material declined. [ABSTRACT FROM AUTHOR]

The 2124Ti aluminum alloy powder was self-designed and fabricated as the matrix, with micro-B4Cp and nano-SiCp adding a certain amount of Ti as the reinforcement, and the 10% B4Cp–2% SiCp/2124Ti composite material was prepared by powder metallurgy. The effects of three multistage solid solutions (G1: 480°C × 2 h + 490°C × 2 h, G2: 480°C × 2 h + 490°C × 2 h + 500°C × 2 h and G3: 480°C × 2 h + 490°C × 2 h + 500°C × 2 h + 510°C × 2 h) on the organization and properties of the 10% B4Cp–2% SiCp/2124Ti composite were investigated, and the optimal aging time of the material was explored after the solid solution. The results show that the G3 solid solution process had the best effect on improving the material performance. With the increase of solid solution temperature and the increase of solid solution time, the hardness of composite material increased significantly after solid dissolution. After 12h of 185°C aging, the hardness reached the peak, which increased by 23.6~50.6 HV compared with the hardness before the solid solution. With the increase of solid dissolution degree, the material conductivity decreased. Moreover, the compressive strength of the composite material was greatly improved after three solid solutions and 12h of aging, which was 690, 750 and 765 MPa namely, but the toughness of the material declined. [ABSTRACT FROM AUTHOR]

The effects of alloy composition (Zn/Mg ratio and Ti content) on the microstructure and properties of Al–3.5Mg–xZn–1.22Cu–0.2Zr–yTi aluminum alloy were studied in this paper. The results show that after solution treatment at 450°C × 2h + 460°C × 2h + 470°C × 2h + 475°C × 2h, when the Zn/Mg ratio of the alloy increases from 3.55 to 3.85, the grain size of the alloy increases, the insoluble phase increases, the dislocation decreases, and the intergranular corrosion resistance decreases gradually. Under the condition of T6 aging, the hardness and electrical conductivity of the alloy decreased at first and then increased, and the compressive strength at room temperature also decreased at first and then increased, and the hardness and compressive strength reached the maximum when the Zn/Mg ratio was 3.85. When Zn/Mg is constant, with the increase of Ti content (0–0.88 wt %), the recrystallization degree of the alloy decreases, the insoluble phase increases, the dislocation density and strengthening value gradually decrease, the inter-granular corrosion resistance decreases gradually, and the hardness, electrical conductivity and compressive strength of the alloy decrease gradually under T6 aging. [ABSTRACT FROM AUTHOR]

In this paper, Ti–5.4Al–4.1Mo–5V–3Cr–1Zr was studied by the secondary processing method of equal channel angular extrusion and heat treatment. Different heat treatment processes were adopted, including 820/880°C solution-580°C aging, 820/880°C solution-ECAP-580°Caging, ECAP-820/880°C solid solution –580°C aging. The oxidation characteristics of thealloy were evaluated by scanning electron microscopy (SEM), optical microscopy (OM) and X-ray diffraction (XRD). The overall anti-oxidation performance is solid solution-ECAP-aging > ECAP-solid solution-aging > solid solution-aging. [ABSTRACT FROM AUTHOR]

The influences of adding different amount of Ti (0%, 0.39%, 0.87%) and three kinds of different aging processes (T6, T6I6, RRA) on the microstructure and properties of Al-11.3Zn-3.2Mg-1.3Cu-0.2Zr-0.1Sr were investigated. Results show that an appropriate amount of Ti can effectively inhibit grain growth and thus achieve the effect of grain refinement. The contribution of dislocation density and dislocation strengthening become the biggest when Ti content is 0.39%. At the same time, the intergranular corrosion depth is the lowest when Ti content is 0.39%. Among the three aging processes, the alloys reach the greatest hardness and tensile strength in T6I6. The biggest tensile strength reaches 716.77 MPa. However, when aging at RRA, the alloys obtain the greatest elongation, reaching 7.2%, as well as the good corrosion resistance. [ABSTRACT FROM AUTHOR]

We propose two spatial second-order schemes for linear radiative transfer equations by using the idea of the unified gas kinetic scheme (UGKS) to construct the numerical boundary fluxes, and show that the proposed schemes are both positive and asymptotic preserving. The UGKS was proposed by Xu and Huang (J Comput Phys 229:7747–7764, 2010) for continuum and rarefied flows firstly, and was then applied to a linear radiative transfer equation by Mieussens in (J Comput Phys 253:138–156, 2013) where the asymptotic preserving property of UGKS is shown. Although it is asymptotic preserving, UGKS can not always keep the positivity of solutions. We first apply UGKS to discretize a linear radiative transfer equation to have a spatial second-order scheme. Then, by a detailed analysis of the numerical boundary fluxes, we are able to find the reasons why the positive preserving property of UGKS fails. Finally, we carefully employ a linear scaling limiter and a flux correction to make UGKS positive-preserving but still asymptotic-preserving. Consequently, we propose two spatial second-order positive and asymptotic preserving unified gas kinetic schemes for the linear radiative transfer equation, thus improving the earlier work (J Comput Phys 444:110546, 2021) where only a first-order positive and asymptotic scheme is developed. The proposed schemes can well capture the solution of the diffusion limit equation in optically thick regions without requiring the cell size being smaller than the photon’s mean free path, while the solution in optically thin regions can also be well resolved in a natural way. To our best knowledge, this is the first time that a spatial second-order positive and asymptotic preserving gas kinetic scheme for linear radiative transfer equations is constructed. Several numerical experiments are included to validate the spatial second-order accuracy, positive- and asymptotic-preserving properties of the proposed schemes. [ABSTRACT FROM AUTHOR]

This study aims to investigate the microstructure and properties of Al-Zn-Mg-Cu alloy that is subjected to a coupled aging treatment, interrupted aging (T6I4) and retrogression and re-aging (RRA). For this purpose, the properties were systematically investigated through the tests of Vickers hardness, tension, and intergranular corrosion. The matrix precipitates were analyzed by transmission electron microscopy. According to the experimental results, the alloy treated by T6I4-RRA was improved by 37% in elongation with the loss of 2% in strength compared to that treated by peak aging (T6). In addition, the corrosion depth of the alloy treated by coupled aging decreased by 40% compared to that of the T6-aged material. According to the microstructure investigations, finer precipitates were formed in the T6I4-RRA-aged alloy, accompanied with intermittent grain boundary precipitates and appropriate precipitate-free zones. Importantly, this peculiar microstructure contributes to resolving the contradiction between strength properties and corrosion resistance of Al-Zn-Mg-Cu alloy. [ABSTRACT FROM AUTHOR]

In this paper, we establish the existence and uniqueness of the local strong solution to the Cauchy problem of the inhomogeneous incompressible primitive equations in a periodic domain. Inspired by the work (J. Li in J. Differ. Equ. 263:6512–6536, 2017), we remove the compatibility condition required in (Q. Jiu and F. Wang in Acta Math. Sci. Ser. B Engl. Ed. 40:1316–1334, 2020), and permit the initial density with vacuum. Meanwhile, we prove the existence of the eigenfunctions to the hydrostatic Stokes operator. [ABSTRACT FROM AUTHOR]

RNA editing is a post-transcriptional modification with a cell-specific manner and important biological implications. Although single-cell RNA-seq (scRNA-seq) is an effective method for studying cellular heterogeneity, it is difficult to detect and study RNA editing events from scRNA-seq data because of the low sequencing coverage. To overcome this, we develop a computational method to systematically identify RNA editing sites of cell types from scRNA-seq data. To demonstrate its effectiveness, we apply it to scRNA-seq data of human hematopoietic stem/progenitor cells (HSPCs) with an annotated lineage differentiation relationship according to previous research and study the impacts of RNA editing on hematopoiesis. The dynamic editing patterns reveal the relevance of RNA editing on different HSPCs. For example, four microRNA (miRNA) target sites on 3ʹ UTR of EIF2AK2 are edited across all HSPC populations, which may abolish the miRNA-mediated inhibition of EIF2AK2. Elevated EIF2AK2 may thus activate the integrated stress response (ISR) pathway to initiate global translational attenuation as a protective mechanism to maintain cellular homeostasis during HSPCs' differentiation. Besides, our findings also indicate that RNA editing plays an essential role in the coordination of lineage commitment and self-renewal of hematopoietic stem cells (HSCs). Taken together, we demonstrate the capacity of scRNA-seq data to exploit RNA editing events of cell types, and find that RNA editing may exert multiple modules of regulation in hematopoietic processes. [ABSTRACT FROM AUTHOR]

The effect of Ti and Ce microalloying on the mechanical properties of Al-9Si-3.5Cu-0.2Zr-0.1Sr cast aluminum alloy was investigated, and it was hoped that the cast aluminum alloy with excellent comprehensive properties could be obtained. On the basis of Zr-Sr microalloyed cast aluminum alloy (Al-9Si-3.5Cu-0.2Zr-0.1Sr), the effects of 0.2Zr-0.1Sr-0.16Ti ternary microalloying and 0.2Zr-0.1Sr-0.16Ti-0.1Ce quaternary microalloying on the microstructure and properties of the alloy were investigated. The experimental results show that compared with Zr-Sr microalloying, Zr-Sr-Ti microalloying and Zr-Sr-Ti-Ce microalloying can effectively refine the microstructure, improve the modification effect of Si phase, and promote the improvement of Al2Cu phase, thus improving the properties. The higher the degree of microalloying, the hardness is gradually increasing, but the electrical conductivity is gradually decreasing. Zr-Sr-Ti microalloying can increase the tensile strength of the alloy to 400.07 MPa and the elongation to 9.5%. Zr-Sr-Ti-Ce microalloying do not continue to improve the properties of the alloy, and the tensile strength and elongation after fracture decrease to a certain extent due to the addition of Ce. Therefore, the best comprehensive properties can be obtained by Zr-Sr-Ti microalloying (Al-9Si-3.5Cu-0.2Zr-0.1Sr-0.16Ti). [ABSTRACT FROM AUTHOR]

In this study, the effects of magnesium addition on the microstructure and comprehensive properties of Al-5Si-5.3Cu-0.3Sr-0.2Zr-0.2Y-0.06Ti alloys were investigated by optical microscope, scanning electron microscope, transmission electron microscope, hardness tester, and tensile testing machine. It is found that the addition of magnesium increases the number of undissolved particles in the alloy. However, on the one hand, magnesium addition refines the θ′ phase and increases its number density in the alloy. On the other hand, it generates a smaller Q′ phase. Both phases can enhance the precipitation strengthening and dislocation strengthening of the alloy. In addition, adding magnesium reduces the width of the precipitation-free zone (PFZ) and changes the distribution of grain boundary precipitates (GBPs). At 1% magnesium addition, the dislocation strengthening and precipitation strengthening effects of the θ′ and Q′ phases were the best, the width of PFZ was the smallest, and the GBPs were discontinuously arranged along the PFZ. Therefore, a high-strength, high-hardness, and intergranular corrosion-resistant cast aluminum alloy with dense structure, a tensile strength of 364.4 MPa, elongation of 4.87%, hardness of 145.4 HV, and intergranular corrosion grade of 3 was obtained. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of the TB8 titanium alloy were controlled by a secondary processing technology of solution-equal channel angular pressing (ECAP)-aging treatment, which combined strong plastic deformation with heat treatment. The effects of ECAP and heat treatment on the microstructure and properties of the titanium alloy were systematically investigated by optical microscopy (OM), scanning electron microscopy (SEM), hardness tests, and tensile property analysis. The results indicate that the metallographic structure without ECAP treatment is mainly equiaxed β-phase, while that after ECAP treatment is equiaxed β-phase with grain fragmentation, slip bands, and new small grains. After 850 °C solution-ECAP-520 °C aging treatment, the titanium alloy has the smallest grain size, while the directionality of tissue growth along the ECAP direction is the most apparent. Under the same solution-aging conditions, the hardness of the titanium alloy increases from 431.5 to 531.2 HV compared to that without ECAP treatment, i e, increases by 23.11%, and the tensile strength increases from 1 045.30 to 1 176.25 MPa, i e, increases by 12.5%. [ABSTRACT FROM AUTHOR]

GNPs/Ti β21S composites with various graphene additions were prepared by spark plasma sintering with Ti β21S powders and graphene powders as raw materials. The effects of graphene on the microstructure, phase composition and oxidation resistance at 1073 K and 1173 K were investigated. The results showed that all GNPs/Ti β21S composites possessed the porosity of not more than 0.2% and the average hardness higher than 470 HV and the oxidation resistance was influenced by the GNPs content. The GNPs/Ti β21S composites with various graphene additions oxidized at 1073 K and 1173 K were composed of TiO2, Ti, Nb2O3, Al2O3, MoO2, SiO2, and Ti2O3. At 1073 K, Ti β21S-0.8 wt.% GNPs composite exhibited the thinner oxidized layer and possessed better oxidation resistance than that of the other composites. At 1173 K, Ti β21S-0.2 wt.% GNPs composite possessed better oxidation resistance than that of the other composites. [ABSTRACT FROM AUTHOR]

This paper used Ti-5.4Al-4.1Mo-5 V-3Cr-1Zr (Ti-555) as the study material, and secondary processing methods consisting of the combination of equal channel angular pressing (ECAP) and heat treatment were adopted. The effect of different processes such as 820/880 °C solid solution-580 °C aging, 820 / 880 °C solid solution-ECAP-580 °C aging, and ECAP-820/880 °C solid solution-580 °C aging on the high-temperature corrosion behavior of the alloy was studied in 75 wt.% NaCl + 25 wt.% Na2SO4 at 800 °C for 40 h. The corrosion characteristics of the alloy were evaluated via scanning electron microscope (SEM), optical microscope (OM), and x-ray diffraction (XRD). The result shows that the weight gain curve tends to be stable after 35 h, and the lowest weight gain was observed in the alloy treated at 880 °C solid solution-ECAP-580 °C, which is 0.88 mg·cm−2. The corroded surface is mainly composed of TiO2 and Al2O3. The thickness of the corroded section of the titanium alloy aged at 820/880 °C solid solution-ECAP-580 °C is 70 and 50 μm, respectively. Overall, the best high-temperature corrosion resistance of the Ti-555 alloy was obtained when subjected to 880 °C solid solution-ECAP-580 °C aging treatment. [ABSTRACT FROM AUTHOR]

We prove existence and uniqueness of solutions to a modified Boussinesq system with no temperature diffusion, where we modify the Biot–Savart law to make the velocity more singular. Our results are proven for solutions of low regularity, and allows, in particular, the transport of temperature patches with regular boundary. The main new tool is a commutator estimate that requires only a fractional derivative on the velocity. [ABSTRACT FROM AUTHOR]

In this paper, new titanium matrix composites (TMCs) with in situ synthesized multiphase (TiB, TiC, Ti5Si3) hybrid reinforcement were prepared by spark plasma sintering (SPS) using Ti555-type titanium alloy (Ti–5.4Al–4.03Mo–3.93V–2.37Cr–0.01Zr) and B4CP, CNT, and SiCP as primary powders. The effects of different reinforcements on the hot corrosion performance of the materials were investigated by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), and the corrosion weight gain, corrosion thickness and corrosion products were analyzed and tested. The results showed that the corrosion products of the base alloy, TMC1 (3.5 vol % B4CP) and TMC3 (3.5 vol % B4CP + 1.5 vol % CNT) were mainly Al2O3, TiO2, NaTiO2 and TiS2, while TMC2 (3.5 vol % B4CP + 1.5 vol % SiCP), in addition to the above products SiO2 was also detected, which has a good corrosion resistance. Furthermore, the corrosion weight gain and corrosion depth of the matrix, TMC1, TMC3, and TMC2 gradually decreased, with corrosion depths of 49, 37, 23, and 14 μm, respectively, indicating that the corrosion resistance of the composites gradually increased, with TMC2 having the best corrosion resistance and the lowest corrosion weight gain of 10.264 mg cm–2. Throughout the corrosion process, the excellent hot corrosion resistance the degree is TMC2 > TMC3 > TMC1 > matrix in order. [ABSTRACT FROM AUTHOR]

Background: Cetuximab, a monoclonal antibody targeting epidermal growth factor receptor (EGFR), is effective for RAS wild-type metastatic colorectal cancer (mCRC) patients. However, cetuximab resistance often occur and the mechanism has not been fully elucidated. The purpose of this study was to investigate the role of asparaginyl endopeptidase (AEP) in cetuximab resistance. Methods: Differentially expressed genes between cetuximab responders and non-responders were identified by analyzing the gene expression profile GSE5851, retrieved from Gene Expression Omnibus (GEO). The potential genes were further validated in cetuximab-resistant CRC cell lines. The expression of AEP in the peripheral blood and tumor tissues of mCRC patients in our hospital were detected by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, respectively. The survival analysis was carried out by Kaplan–Meier method. The function and associated pathways of AEP were further investigated by lentivirus transfection, CCK8 assay, colony formation assay, real-time polymerase chain reaction (qPCR) and western blot. Results: Through bioinformatics analysis, we found that the expression of AEP gene was related to progress free survival (PFS) of mCRC patients treated with cetuximab alone (P = 0.00133). The expression of AEP was significantly higher in the cetuximab-resistant CRC cell lines, as well as in mCRC patients with shorter PFS treated with cetuximab-containing therapy. Furthermore, AEP could decrease the sensitivity of CRC cells to cetuximab in vitro. And the phosphorylation level of MEK and ERK1/2 was increased in AEP overexpression cells. The downregulation of AEP using specific inhibitors could partially restore the sensitivity of CRC cells to cetuximab. Conclusion: The higher expression of AEP could contribute to the shorter PFS of cetuximab treatment in mCRC. The reason might be that AEP could promote the phosphorylation of MEK/ERK protein in the downstream signal pathway of EGFR. [ABSTRACT FROM AUTHOR]

The effects of SiC particles (SiCp) on high temperature oxidation behavior of titanium matrix composites (TMCs) under different powder metallurgy processes were investigated. In situ TiC + Ti5Si3 reinforced titanium matrix composites were prepared by discharge plasma sintering (SPS) and argon protective sintering (APS). The results show that the two processes have a negligible effect on the composition and hardness of the samples, but the hardness of the two samples is significantly improved by adding SiCp. The apparent porosity of SPS process is obviously smaller than that of APS process, whereas, the apparent porosity increases slightly with the addition of SiCp. The oxide layer thickness and mass gain of the samples obtained by SPS process are smaller than those obtained by APS process. The oxide thickness and mass gain of both processes are further reduced by adding SiCp. The SPS composites showed the best high temperature oxidation resistance. Therefore, TMCs with SiCp by SPS can effectively improve the high-temperature oxidation behavior of the materials. [ABSTRACT FROM AUTHOR]

TiC and TiC + TiB were prepared through an in-situ reaction and powder metallurgy based on Ti-Mo-Nb-Al-Si matrix powder, CNTs (Carbon Nanotubes) and CNTs + B4C, which reinforces TB8 titanium matrix composites (TMCs). Firstly, the hot corrosion performance of three kinds of TiC (0, 2.5, and 5vol.-%) and one TiC + TiB (3.5 + 3.5vol.%) was investigated in Na2SO4(75wt.%)-NaCl(25 wt.%) saturated solution at 800°C. And then the corrosion kinetics indicated that the corrosion weight gain of 3.5vol.% TiC + 3.5vol.% TiC reinforced titanium matrix composite only reached 7.48 mg/cm2. Secondly, the features of corrosion scales formed on the composites were characterized based on x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The patterns of XRD illustrated the corrosion products are composed of TiO2, Al2O3, SiO2, Nb2O5, TiCl2, NaTiO2 and NaAlO2. SEM showed that the corrosion surface of TiC + TiB composite is the densest among the four composite materials (0 vol.% TiC, 2.5 vol.%TiC, 5 vol.%TiC, and 3.5 vol.%TiC + 3.5 vol%TiB). In addition, its corrosion layer thicknesses have little difference, which are 53, 46, 49, and 44 μm, respectively. Finally, the composite material with TiC + TiB has the best hot corrosion resistance, which verifies by the experimental analysis. [ABSTRACT FROM AUTHOR]

700-MPa-grade aluminum alloys (AAs) were processed by T6 and T6I4 aging treatments. The nanostructures and phases of obtained AAs were analyzed using a transmission electron microscope and x-ray diffraction, respectively. The effects of aging treatment on the tensile property and intergranular corrosion of AAs were investigated using a tensile machine and optical microscope, and the fracture morphologies and corrosion microstructure were observed using a scanning electron microscope and its equipped energy-dispersive spectrometer. The results show that the fine matrix precipitates, narrow precipitate free zones and discontinuous distribution of grain boundary precipitates (GBPs) are the characteristics of T6I4 aged AA, while those of T6 aged AA are the opposite. The matrix precipitates of T6I4 aged AA are transformed from Guinier–Preston zones to η′ phases, while those of T6 aged AA are transformed from η′ to η phases. The uniform distribution of fine matrix precipitates in the T6I4 aged AA is the main factor for its high tensile strength. The continuous GBPs in the T6 aged AA promote the formation of short-circuit cell to aggravate the intergranular corrosion, while those in the T6I4 aged AA are the opposite. [ABSTRACT FROM AUTHOR]

Al-8.8Zn-2.2Mg-xCu-0.2Zr-0.1Sr-yTi aluminum alloys (AAs) with the different Cu and Ti contents were self-designed and fabricated by melting, casting and extrusion techniques, which were aged by T6 process. The microstructure and intergranular morphologies of obtained AAs were observed using an optical microscope (OM). The morphologies of AAs after intergranular corrosion were investigated using a scanning electron microscope (SEM), and their chemical composition and dislocation enhancement were analyzed using an energy-dispersive spectrometer (EDS) and x-ray diffraction (XRD), respectively. The hardness and electrical conductivity of AAs were measured using a Vickers hardness and eddy current conductivity testers, respectively, and the tensile properties were investigated using a drawing machine. The results show that the addition of Ti refines the grains of AAs, which inhibits the recrystallization and improves the hardness, tensile strength, and corrosion performance. Moreover, the excessive Cu content suppresses the grain refinement effect of Ti, which decreases the tensile strength of AAs. The high Cu content in the AAs generates coarse and brittle phases to decrease the plasticity and electron scattering of AAs, resulting in the enhancement of electrical conductivity. [ABSTRACT FROM AUTHOR]

In this paper, the metastable β titanium alloy TB8 (Ti-12.76Mo-2.13Nb-2.73Al-0.16Si) was used as the starting material, and the secondary processing method combining equal channel angular pressing (ECAP) and heat treatment was adopted. Moreover, the effects of different processes (800 °C/850 °C solid solution-520 °C aging, ECAP-800 °C/850 °C solid solution-520 °C aging and 800 °C/850 °C solid solution-ECAP-520 °C aging) on the high temperature oxidation resistance of the material were studied with the help of scanning electron microscope (SEM), optical microscope (OM) and X-ray diffractometer (XRD). It was found that the phase composition of the samples after cyclic oxidation at a high temperature of 850 °C for 50 h is similar mainly TiO2, Al2O3, SiO2, MoO3 and Nb2O5. The grains of the TB8 titanium alloy treated with 850 °C solid solution-ECAP-520 °C aging treatment are obviously refined, and the surface microstructure is the most smooth and compact, forming a continuous Al2O3 protective film. The thickness of the oxide layer is the smallest (55.0 μm), which is only 28.45 %-39.29 % of that of other secondary processing titanium alloys. In addition, the average oxidation rate and parabolic rate constant of titanium alloy treated by 850 °C solid solution-ECAP-520 °C aging are the lowest, which are 0.0036 mg·cm-2·h-1 and 45.30 mg2·cm-4·h-1, respectively. The results show that the TB8 titanium alloy has the best high temperature oxidation resistance after 850 °C solid solution-ECAP-520 °C aging treatment. [ABSTRACT FROM AUTHOR]

Key message: The chemical analysis and the expression patterns of related genes were determined to reveal and compare the adaptation mechanism of T. mongolica and Z. xanthoxylum to arid environments. Tetraena mongolica Maxim, the only member of the Tetraena genus in the Zygophyllaceae, is endemic to the northwest of China and is normally accompanied by another plant species in the same taxonomic family, Z. xanthoxylum (Bunge) Engl, and they play a key role in the ecology of the local environment. In order to survive in the local arid environment, many plants have developed a variety of adaptive mechanisms, including the formation of effective protective barrier, such as suberin in the stems and roots that can prevent plants from losing water and improve their adaptability to water-deficient environments. Previous studies have shown that Z. xanthoxylum had stronger drought tolerance than T. mongolica. Here, the water loss rates, the chemical composition of suberin and associated fatty acids in the periderms of stems and roots from T. mongolica and Z. xanthoxylum were determined. The expression level of genes related to suberin and associated fatty acid metabolism of the two species were also analyzed through transcriptome sequencing. The results showed that the stem and root periderms of these two species had similar chemical composition of suberin and fatty acids; however, much higher amount of suberin monomers and fatty acids were found in T. mongolica. Accordingly, transcriptome sequencing showed that more of the differentially expressed genes (DEGs) associated with suberin and associated fatty acid biosynthesis were up-regulated in the stem periderms of T. mongolica; however, minority of DEGs were up-regulated in root periderms of T. mongolica, compared with Z. xanthoxylum. This study lays an important foundation for revealing the adaptation mechanism of T. mongolica and Z. xanthoxylum to arid environments and for comparing the adaptability differences of these two species. [ABSTRACT FROM AUTHOR]

Herein, Al-Si-Cu aluminum alloy was prepared and the effect of forging on the microstructure and mechanical properties of novel Al-9Si-5Cu-0.2Zr-0.1Sr-0.16Ti-0.1Ce cast aluminum alloy was investigated. The microstructure analyses show that after forging, the casting defects disappeared, and the irregular Si-eutectic was spheroidized and randomly distributed. The coarse intermetallic compounds (IMCs) gradually dissolved during the solution treatment, and the increased supersaturation of the matrix promoted precipitation kinetics, leading to the coexistence of dense fine θ and θ' strengthening phases. Moreover, the dislocation strengthening effect for the forged alloy was enhanced. The mechanical tests show that compared to the as-cast alloy, the mechanical properties of the forged alloy including the hardness, yield strength, tensile strength, and plasticity were improved by optimizing the microstructure. [ABSTRACT FROM AUTHOR]

In situ hybrid-reinforced Ti555 titanium matrix composites (TMCs) (TiB + TiC + Ti5Si3) were prepared by low-energy ball milling and discharge plasma sintering using Ti555 titanium alloy powder and B4Cp, SiCp, and CNT as the raw materials, and then solution and aging treatment were performed. The effects of the content and type of reactants on the microstructure, microhardness of phase composition, and high-temperature oxidation behavior of the composites were investigated under the addition of different contents of B4Cp and addition of SiCp or CNT. A hardness test shows that the hardness of the composite with a volume fraction of 3.5%B4Cp+1.5%CNT (1243.36 HV) is more than twice that of the matrix (539.21 HV). An XRD analysis shows that the oxidation phase is mainly composed of TiO2, Al2O3, and SiO2. Scanning electron microscopy (SEM) showed that the oxide layer (32 μm) was denser than the matrix (56 μm) in the composite with a volume fraction of 3.5%B4Cp + 1.5%SiCp at 800 °C for 100 h. The results show that the addition of B4Cp and CNT can effectively improve the hardness of TMCs, and the addition of B4Cp and SiCp can effectively improve the high-temperature oxidation resistance of TMCs. [ABSTRACT FROM AUTHOR]

Solutions to the 2D Navier–Stokes equations with full dissipation in the whole space R 2 always decay to zero in Sobolev spaces. In particular, any perturbation near the trivial solution is always asymptotically stable. In contrast, solutions to the 2D Euler equations for inviscid flows can grow rather rapidly. An intermediate situation is when the dissipation is anisotropic and only one-directional. The stability and large-time behavior problem for the 2D Navier–Stokes equations with only one-directional dissipation is not well-understood. When the spatial domain is the whole space R 2 , this problem is widely open. This paper solves this problem when the domain is T × R with T being a 1D periodic box. The idea here is to decompose the velocity u into its horizontal average u ¯ and the corresponding oscillation u ~ . By making use of special properties of u ~ , we establish a uniform upper bound and the stability of u in the Sobolev space H 2 , and show that u ~ in H 1 decays to zero exponentially in time. [ABSTRACT FROM AUTHOR]

In this paper, we study the inhomogeneous boundary value problem for the steady MHD system of a viscous incompressible fluid in an arbitrary bounded multiply connected domain. We prove the existence of generalized solutions of the steady MHD system with some smallness conditions on the boundary values. [ABSTRACT FROM AUTHOR]

Limonium sinuatum, a member of Plumbaginaceae commonly known as sea lavender, is widely used as dried flower. Five L. sinuatum varieties with different flower colors (White, Blue, Pink, Yellow, and Purple) are found in saline regions and are widely cultivated in gardens. In the current study, we evaluated the salt tolerance of these varieties under 250 mmol/L NaCl (salt-tolerance threshold) treatment to identify the optimal variety suitable for planting in saline lands. After the measurement of the fresh weight (FW), dry weight (DW), contents of Na+, K+, Ca2+, Cl−, malondialdehyde (MDA), proline, soluble sugars, hydrogen peroxide (H2O2), relative water content, chlorophyll contents, net photosynthetic rate, and osmotic potential of whole plants, the salt-tolerance ability from strongest to weakest is identified as Pink, Yellow, Purple, White, and Blue. Photosynthetic rate was the most reliable and positive indicator of salt tolerance. The density of salt glands showed the greatest increase in Pink under NaCl treatment, indicating that Pink adapts to high-salt levels by enhancing salt gland formation. These results provide a theoretical basis for the large-scale planting of L. sinuatum in saline soils in the future. [ABSTRACT FROM AUTHOR]

In this paper, carbon nanotubes (CNTs) reinforced Ti–12.8Mo–2.1Nb–2.7Al–0.2Si (TB8) matrix composites were synthesized by low-energy ball milling and cold pressing sintering. Based on theoretical calculation and thermodynamic simulation method to obtain phase transition points, CNTs/TB8 composites were subjected to a solid-solution and aging treatment. The effect of heat treatment and CNTs content on microstructure and mechanical properties of the composites was investigated. The results indicated that 0.5 wt% CNTs/TB8 composite formed α + β phase structure after different heat treatment processes, α phase dispersed in the β phase, grain refinement was distinct, and the microhardness of composite was significantly improved. It had the effect of solution strengthening and dispersion strengthening. The composites’ microhardness was the highest, reaching 615.3HV after 850 °C/3 h/AC and 550 °C/6 h/AC heat treatment. Under these conditions, with the CNTs content increasing, the microhardness of composite increased initially and then decreased. The microhardness of the composite containing 1.0 wt% CNTs reached 635.1HV, which was an increase of 21.9% compared to without executing heat treatment. In addition, the compression property of the titanium matrix composite at room temperature was excellent; the compressive strength and the fracture strain were 1263 MPa and 18.5%, respectively. [ABSTRACT FROM AUTHOR]

The hydrostatic equilibrium is a prominent topic in fluid dynamics and astrophysics. Understanding the stability of perturbations near the hydrostatic equilibrium of the Boussinesq system helps gain insight into certain weather phenomena. The 2D Boussinesq system focused here is anisotropic and involves only horizontal dissipation and horizontal thermal diffusion. Due to the lack of the vertical dissipation, the stability and precise large-time behavior problem is difficult. When the spatial domain is R 2 , the stability problem in a Sobolev setting remains open. When the spatial domain is T × R , this paper solves the stability problem and specifies the precise large-time behavior of the perturbation. By decomposing the velocity u and temperature θ into the horizontal average (u ¯ , θ ¯) and the corresponding oscillation (u ~ , θ ~) , and deriving various anisotropic inequalities, we are able to establish the global stability in the Sobolev space H 2 . In addition, we prove that the oscillation (u ~ , θ ~) decays exponentially to zero in H 1 and (u , θ) converges to (u ¯ , θ ¯) . This result reflects the stratification phenomenon of buoyancy-driven fluids. [ABSTRACT FROM AUTHOR]

Dorsal root ganglia (DRG) sensory neurons can transmit information about noxious stimulus to cerebral cortex via spinal cord, and play an important role in the pain pathway. Alterations of the pain pathway lead to CIPA (congenital insensitivity to pain with anhidrosis) or chronic pain. Accumulating evidence demonstrates that nerve damage leads to the regeneration of neurons in DRG, which may contribute to pain modulation in feedback. Therefore, exploring the regeneration process of DRG neurons would provide a new understanding to the persistent pathological stimulation and contribute to reshape the somatosensory function. It has been reported that a subpopulation of satellite glial cells (SGCs) express Nestin and p75, and could differentiate into glial cells and neurons, suggesting that SGCs may have differentiation plasticity. Our results in the present study show that DRG-derived SGCs (DRG-SGCs) highly express neural crest cell markers Nestin, Sox2, Sox10, and p75, and differentiate into nociceptive sensory neurons in the presence of histone deacetylase inhibitor VPA, Wnt pathway activator CHIR99021, Notch pathway inhibitor RO4929097, and FGF pathway inhibitor SU5402. The nociceptive sensory neurons express multiple functionally-related genes (SCN9A, SCN10A, SP, Trpv1, and TrpA1) and are able to generate action potentials and voltage-gated Na+ currents. Moreover, we found that these cells exhibited rapid calcium transients in response to capsaicin through binding to the Trpv1 vanilloid receptor, confirming that the DRG-SGC-derived cells are nociceptive sensory neurons. Further, we show that Wnt signaling promotes the differentiation of DRG-SGCs into nociceptive sensory neurons by regulating the expression of specific transcription factor Runx1, while Notch and FGF signaling pathways are involved in the expression of SCN9A. These results demonstrate that DRG-SGCs have stem cell characteristics and can efficiently differentiate into functional nociceptive sensory neurons, shedding light on the clinical treatment of sensory neuron-related diseases. [ABSTRACT FROM AUTHOR]

TB8 (Ti-13.58Mo-2.15Nb-3.27A1-0.21Si) is a metastable β titanium alloy with excellent mechanical properties. In this paper, TiC/TB8 and TiC + TiB/TB8 titanium matrix composites (TMCs) were prepared by spark plasma sintering (SPS). In addition, the cyclic oxidation interval measurement method was used to compare the high-temperature oxidation behavior of TB8 titanium alloys with different volume fractions of TiC and TiC + TiB reinforced TB8 composites. Studies have shown that after cyclic oxidation at 800 °C for 100 h, the oxidation law of TB8 is a mixture of linear and parabolic, while TMC1 (2.5 vol.% TiC), TMC3 (5 vol.% TiC) and TMC4 (3.5 vol.% TiC + 3.5 vol.% TiB) oxidation mainly follows the parabolic law. Moreover, the oxidation weight gain of TB8 after oxidation is as high as 9.83 mg/cm2, while the oxidation weight gain of TMC1, TMC3 and TMC4 is only 5.95 mg/cm2, 6.81 mg/cm2 and 2.83 mg/cm2. It shows that during the entire oxidation process, the order of excellent high-temperature oxidation resistance is TMC4 > TMC1 > TMC3 > TB8. [ABSTRACT FROM AUTHOR]

TiC and Ti5Si3 reinforced titanium matrix composites (TMCs) were successfully prepared by an in situ reaction of SiC particles with Ti-Al-Sn-Zr alloy through powder metallurgy. By studying the microstructure and phase composition after corrosion at 750 and 850 °C for 30 h in a corrosive environment of 25% NaCl + 75% Na2SO4, the resistance to hot corrosion of composite materials with different contents of SiC particles was valuated. The results showed that at 750 °C, the corrosion depth (18 μm) of the TMCs with 10 vol.% SiCp was 75% less than that of the matrix. After the samples corrosion for 30 h at 750 and 850 °C, the maximum corrosion gain of the TMCs with 10 vol.% SiCp was 6.16 and 30.57 mg cm−2, respectively. The maximum corrosion mass gain decreased by 60.03 and 35.49% compared with the matrix at 750 °C (15.41 mg cm−2) and 850 °C (47.39 mg cm−2). In addition, the XRD result showed that corrosion products of three composites are similar at 750 and 850 °C, and mainly composed of TiO2, SiO2, Al2O3, NaTiO2, Na2Si2O5 and TiS2. The TMCs with 10 vol.% SiCp had more SiO2. All the data showed that SiCp was beneficial to the hot corrosion properties of the samples, and as the content of SiCp increased, the corrosion resistance was better. [ABSTRACT FROM AUTHOR]

Ti-6Al-4Sn-9Zr-1.21Nb-1.6Mo-0.3Si powders and graphene nanoplatelets (GNPs) were used as the raw materials to prepare GNPs/Ti-Al-Sn-Zr-Nb-Mo-Si composites by using spark plasma sintering method. The effect of adding 1-4 wt.% GNPs on the porosity, hardness, microstructure, phase composition and oxidation resistance of composites at 1073 and 1173 K were investigated. The results show that all GNPs/Ti-Al-Sn-Zr-Nb-Mo-Si composites before oxidation possessed the porosity of not more than 0.20% and the average hardness of higher than 480 HV. The porosity of composites decreased and the average hardness of composites increased, while the content of graphene increased. Compared with the matrix, Ti-6Al-4Sn-9Zr-1.21Nb-1.6Mo-0.3Si-4GNP possessed highest hardness (533.9 HV) and lowest porosity (0.14%). Compared with the composites before oxidation, the hardness of the composites oxidized at 1073 K and 1173K decreased by less than 10%, which meant that the composites still possessed excellent performance at high temperature. GNPs/Ti-Al-Sn-Zr-Nb-Mo-Si composites with adding various graphene oxidized at 1073 K and 1173K were composed of TiO2, Al2O3, SiO2, SnO2, Nb2O5, Ti3O5, ZrO2 and MoO3 and MoSi2 was just generated after oxidation at 1073 K. The GNPs content and oxidation temperature influenced the oxidation resistance. At 1173 K, the composite with 1 wt.% GNPs possessed the lowest average oxidation rate (2.57 × 10−3 g m−2 h−1), which was about 84.7% less than that of the matrix alloy, and its thickness of the oxidized layer was thinnest, which was about 12 μm. The oxidation resistance of the composites with adding 1-4 wt.% GNPs was better than the unreinforced alloy. [ABSTRACT FROM AUTHOR]

In this paper, we consider the classical solutions to a model of two-dimensional incompressible inviscid Boussinesq–Bénard equations. Notice that, in the case when the source term of temperature equation in this model is the second component of velocity u 2 or no source term, there is no global-in-time existence result for the general initial data. Here, if the source term is only chosen as Δ u 2 , then we can obtain the global well-posedness, inviscid limit and some exponential decay estimates. Our key observation is the nice symmetrical structure hidden in the corresponding system, which plays an extremely important role in the global well-posedness studied here. [ABSTRACT FROM AUTHOR]

MicroRNA319 (miR319) plays an important role in leaf development. Although leaf discs are frequently used for plant transformation, little is known about the function of miR319 in shoot regeneration from leaf explants. To investigate the role of miR319 in de novo shoot organogenesis from leaf explants, the MIR319 gene was overexpressed in petunia (Petunia×hybrida), under the control of the 35S promoter. Petunia leaves overexpressing miR319 (miR319-OX) showed several morphological abnormalities, such as rounded, uneven, and curled leaf blade, larger leaf size, and smaller and rounded abaxial surface cells, which were differences compared to wild-type (WT) leaves. Additionally, miR319-OX leaf explants demonstrated enhanced shoot organogenesis on a growth medium containing 6-benzylaminopurine (BA) at shoot-inducing concentrations, and cytokinin-independent shoot regeneration on hormone-free medium compared with WT explants. Quantitative real-time PCR (qRT-PCR) analysis indicated that the expression of petunia NO APICAL MERISTEM (PhNAM) and SHOOT MERISTEMLESS (PhSTM) genes was markedly increased in miR319-OX explants compared with WT explants under shoot induction conditions, whereas the expression of petunia cytokinin-responsive type-A response regulator genes, PhRR2 and PhRR3, showed no differences in expression between WT and miR319-OX leaf explants. These results suggest that miR319 regulates the formation of shoot meristems from leaf explants in petunia during in vitro culture. [ABSTRACT FROM AUTHOR]

Buoyancy-driven fluids such as many atmospheric and oceanic flows and the Rayleigh–Bénard convection are modeled by the Boussinesq systems. By rigorously estimating the large-time behavior of solutions to a special Boussinesq system, this paper reveals a fascinating phenomenon on buoyancy-driven fluids that the temperature can actually stabilize the fluids. The Boussinesq system concerned here governs the motion of perturbations near the hydrostatic equilibrium. When the buoyancy forcing is not present, the velocity of the fluid obeys the 2D Navier–Stokes equation with only vertical dissipation and its Sobolev norm could potentially grow even though its precise large-time behavior remains open. This paper shows that the temperature through the coupling and interaction tames and regularizes the fluids, and causes the velocity (measured in Sobolev norms) to decay in time. Optimal decay rates are obtained. [ABSTRACT FROM AUTHOR]

The paper studied the microstructure and properties of (Al3Zr + ZrB2)p/Al-Zn-Mg-Cu composite by mixed salt reaction (MSR) in different states. The results show that the grain sizes of the aluminum matrix composite are similar and very small, and the average grain size of which is around 3.257 μm. Besides, the precompression and pre-recovery treatment can further improve the mechanical properties and the corrosion resistance. In the pre-recovery, solution, precompression and T6 aging process, the composite material has the best mechanical properties, the hardness and tensile strength of which reaches up to 258 HV and 666 MPa, respectively. Meanwhile, T76 aging is more effective on the exfoliation and intergranular corrosion resistance of the composite material than T6 aging. [ABSTRACT FROM AUTHOR]

The Al-modified boronized coating on Ti-6Al-4V was successfully fabricated to protect the alloy from oxidation by the neutral salt bath method. The thickness of the Al-modified boronized coating (69.8 ± 2 μm) is 36% thicker than that of the simple-boronized coating (51.3 ± 1.5 μm). To evaluate the oxidation resistance, the high-temperature oxidation behavior was analyzed by the high-temperature oxidation experiment at 700 and 900 °C. The results show that after oxidation, the Al-modified boronized coating was mainly comprised of TiO2, Al2O3, Al3Ti, Ti3B4 and TiS phases, and the surface of the Al-modified boronized coating is smoother and denser. The thickness of the oxide layer of the Al-modified boronized coating is the minimum, which is 11 ± 0.3 μm and 13 ± 0.5 μm at 700 and 900 °C for 60 h, respectively. The average oxidation rate of the Al-modified boronized coating is − 0.003 and 0.022 mg cm−2 h−1 due to the formation of Al2O3 on the surface. Therefore, adding Al into the simple-boronized coating is beneficial for the high-temperature oxidation resistance. [ABSTRACT FROM AUTHOR]

The effect of various Zn/Mg ratios on the microstructure and properties of cold extruded Al-xZn-2.4Mg-0.84Cu-0.2Zr-0.25Ti aluminum alloys was investigated. The microstructure analyses showed that as the Zn/Mg ratio increased from 3.46 to 3.84 and to 4.04, the recrystallization degree and the undissolved phase gradually increased. Moreover, with the increasing Zn/Mg ratio, the grain size of the alloy was refined, and the dislocation strengthening effect firstly increased and then decreased. The mechanical test results showed that as the Zn/Mg ratio increased from 3.46 to 3.84 and to 4.04, the tensile strength and hardness of the cold extruded Al-xZn-2.4Mg-0.84Cu-0.2Zr-0.25Ti alloy firstly increased and then decreased. The alloy with lower Zn/Mg ratio exhibited better capacitor characteristics, surface protection and corrosion resistance. [ABSTRACT FROM AUTHOR]