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In this study, the nucleation and growth mechanisms of Al11Ce3 intermetallic compounds (IMCs) in a hypereutectic Al–Ce alloy during solidification were investigated through synchrotron radiation X-ray real-time imaging. The results showed that Al11Ce3 IMCs nucleate and grow from the melt as the primary phase at the initial stage of solidification. Growth preferred orientations were observed in two opposite directions, resulting in an I-shaped growth pattern. Based on the minimum energy criterion, the morphology of Al11Ce3 IMCs displayed either hollow cubic tubes or grooves. The nucleation and growth rates of Al11Ce3 IMCs gradually decreased over time, owing to the variations in the Ce concentration in the melt and the undercooling. The nucleation and growth characteristics of Al11Ce3 IMCs can provide the theoretical basis for optimization on the performance of Al–Ce alloys.

AZ31 Mg alloy thin walls are prepared using wire arc additive manufacturing (WAAM) and interlayer ultrasonic impact (UI) techniques with cold metal transition (CMT) serving as the heat source. The microstructure, mechanical and corrosion properties of thin walls prepared by WAAM and WAAM + UI are studied. Results showed that the recrystallization area fraction along traveling direction (TD) increased by 68.6% after UI treatment, and many fine equiaxed crystals were formed, resulting in grain refinement, anisotropy reduction, mechanical and corrosion properties improvement. The average grain size along TD decreased from 66.6 ± 3.5 μm to 32.7 ± 1.6 μm. Through UI treatment, the ultimate tensile strength (UTS) and elongation (EL) along TD increased from 205 MPa to 230 MPa and 13.5%–17%, respectively. The anisotropic percentage of UTS and EL were decreased from 10.8% to 4.5%, and 42.1%–9.7%, respectively. Electrochemical experimental results showed that the average corrosion rate along TD decreased from 1.93 mm year−1 to 1.53 mm year−1. Grain refinement, dislocation density variation and texture strength reduction were the main reasons for these results.

Ultrasound, as an efficient, clean, and safe processing technology, is widely used in industries. Grain refiners are widely used in the refinement of cast alloys. In this study, ultrasonic technology (UT) and Al–5Ti–1B refiner prepared by continuous rheological extrusion (CRE Al–5Ti–1B) were used to modify the recycled Al–Mg–Si-based alloy, and the microstructure and mechanical properties of the recycled Al–Mg–Si-based alloy were studied. The differences in porosity and grain refinement caused by ultrasonic power were discussed. Results showed that, increasing the ultrasonic power can effectively reduce the porosity of the recycled Al–Mg–Si-based alloy. The synergistic effect of UT and CRE Al–5Ti–1B refiner significantly refined α-Al grains and second phases. The increase of ultrasonic power can effectively cause deagglomeration while reducing the nucleation undercooling of α-Al, which promotes the refinement of the recycled Al–Mg–Si-based alloy and significantly improves the mechanical properties. The yield strength (YS), ultimate tensile strength (UTS) and elongation (EL) of the recycled Al–Mg–Si-based alloy were 106 MPa, 210 MPa and 9.4%, respectively. When 0.2 wt% CRE Al–5Ti–1B refiner was added and the ultrasonic power was 150 W, the YS, UTS, and EL were improved by 12.8%, 28.8% and 228.4%, respectively.

In this study, the variations in hydrogen content and oxide content in alloys under 0 W, 500 W, 1000 W, 1500 W, 2000 W, 2500 W, 3000 W, and at 20 kHz, 30 kHz, 40 kHz were investigated. Hydrogen content was assessed using porosity and computed tomography, while oxygen content in the alloy was measured using element analyzer and elemental scanning. Compared to other conditions, the melt had the lowest hydrogen and oxide contents at a frequency of 20 kHz and an ultrasonic power of 2500 W, with values of 0.099 cm3/100 g and 0.0015 %, respectively. Experimental observations also indicate that the variations in hydrogen content and oxide content in the alloy during ultrasonic treatment are almost similar. In most cases, lower hydrogen content corresponds to lower oxide content in the same alloy. This is because hydrogen bubbles and oxides become a single entity. At the same time, ultrasonic purification increases the tensile strength of the alloy to 200.1 MPa and the elongation rate to 0.72 %. This study primarily investigates the relationship between hydrogen bubbles and oxides in aluminum melt under different ultrasonic frequencies and power levels, providing significant reference for the purification of various fluids under ultrasonic fields.

Based on experiments and first-principles calculations, the microstructures and mechanical properties of as-cast and solution treated Mg-10Gd-4Y-xZn-0.6Zr (x = 0, 1, 2, wt.%) alloys are investigated. The transformation process of long-period stacking ordered (LPSO) structure during solidification and heat treatment and its effect on the mechanical properties of experimental alloys are discussed. Results reveal that the stacking faults and 18R LPSO phases appear in the as-cast Mg-10Gd-4Y-1Zn-0.6Zr and Mg-10Gd-4Y-2Zn-0.6Zr alloys, respectively. After solution treatment, the stacking faults and 18R LPSO phase transform into 14H LPSO phase. The Enthalpies of formation and reaction energy of 14H and 18R LPSO are calculated based on first-principles. Results show that the alloying ability of 18R is stronger than that of 14H. The reaction energies show that the 14H LPSO phase is more stable than the 18R LPSO. The elastic properties of the 14H and 18R LPSO phases are also evaluated by first-principles calculations, and the results are in good agreement with the experimental results. The precipitation of LPSO phase improves the tensile strength, yield strength and elongation of the alloy. After solution treatment, the Mg-10Gd-4Y-2Zn-0.6Zr alloy has the best mechanical properties, and its ultimate tensile strength and yield strength are 278.7 MPa and 196.4 MPa, respectively. The elongation of Mg-10Gd-4Y-2Zn-0.6Zr reaches 15.1, which is higher than that of Mg-10Gd-4Y0.6Zr alloy. The improving mechanism of elastic modulus by the LPSO phases and the influence on the alloy mechanical properties are also analyzed.

Heat treatment of Mg10Gd-4Y-xZn-0.6Zr (x = 0, 1, 2 wt%) alloys has been optimized based on thermodynamic calculations and experiments. The phase transformations during the heat treatment and their effect on the mechanical properties of the alloys were discussed. Using thermodynamic calculations, three solution treatment temperatures of 475 °C, 500 °C, and 525 °C were determined, and the phase transformation under these temperatures were calculated and characterized, the results aligned well with experimental results. The optimal solution treatment technology was determined to be 500 °C for 18 h. After solution treatment, experimental alloys were subject to isothermal aging at 225 °C, the peak aging time for the experimental alloys was established. The microstructure under peak-aged state of the alloy was characterized, revealing a co-existed β’ and β1 phases. The GWZ1041K alloy, after peak aging treatment, exhibited optimal mechanical properties, with a tensile strength, yield strength, and elongation of 392.3 MPa, 249.3 MPa, and 5.7%, respectively. The study further analyzed the reasons for the microstructure transformation during the heat treatment and their influence on mechanical properties.

Many experimental results confirm that electromagnetic stirring (EMS) has a good purification effect on the melts, either degassing or removing inclusions, but the mechanism of electromagnetic purification still needs to be further explored. This paper takes M174 alloy as an example, and carries out a more in-depth study on the purification effect of electromagnetic field on the basis of numerical simulation, focusing on the amount of hydrogen present in the ingot, the enhancement effect of electromagnetic field stirring on the mechanical properties of the melt was investigated in terms of the treatment temperature, and the current intensity during electromagnetic stirring. The results show that the tensile strength and elongation of the alloy reached 195.3 MPa and 0.69% after electromagnetic stirring at a current intensity of 60 A, which are very close to the theoretical properties of the alloy of 200.3 MPa and 0.74%, respectively. At the same time, the effect of electromagnetic stirring on the presence of oxides and double oxide film in the melt is slightly explored.

To further improve the strength of an Al–Ce alloy, the effects of electromagnetic stirring treatment, Sc–Zr microalloying, and their compound action on the microstructure and properties of the Al–8Ce alloy were investigated for the first time in this study. The results show that the primary α-Al becomes coarse, the eutectic Al11Ce3 phase is refined and the lamellar spacing increases significantly due to the combined effect of forced convection of electromagnetic field and dendrite fragmentation and nucleation in Al–8Ce alloy after electromagnetic stirring treatment. After the Sc–Zr microalloying treatment of the Al–8Ce alloy, the α-Al changes from a dendritic to fine round morphology, and the eutectic Al11Ce3 phase changes from lamellar to fibrous, which is due to the heterogeneous nucleation of Al3(Sc, Zr) phase and the adsorption refinement caused by the enrichment of Sc and Zr. The optimization effect of Sc–Zr microalloying on the mechanical properties of the Al–8Ce alloy was better than that of electromagnetic stirring and their synergistic treatment. The tensile strength and yield strength of Al–8Ce alloy with Sc–Zr additions were increased from 157 MPa to 85 MPa–192 MPa and 115 MPa, respectively, by 22.3 % and 35.3 %. After aging treatment, the tensile strength (from 192 to 272 MPa) and yield strength (from 115 to 221 MPa) significantly improved owing to the secondary precipitation of Al3(Sc, Zr) particles. The precipitation strengthening of the Al3(Sc, Zr) phase was the main contributor to the high yield strength of the alloy.

This work studied the effect of solution heat treatment on the microstructure and properties of the Al–Cu alloy fabricated by wire arc additive manufacturing (WAAM), and focused on the influence of porosity and second phase evolution on the tensile properties and fatigue resistance of the alloy. The results show that with solution heat treatment at 530 °C for 1h, Al–Cu alloy fabricated by WAAM with low porosity (2.4 %) and high peak hardness (148.2 HV) can be obtained. Higher solution temperatures significantly increased the porosity, and extending the solution time caused the problems of increased porosity, micropore growth, microcracks as well as cavity. Influence of porosity on fatigue resistance is more significant than that on tensile properties. The results of tensile tests suggest that the effect of porosity on the strength of T6-treated alloy is limited and much smaller than that of the precipitation strengthening induced by precipitates, while the results of the fatigue crack propagation tests imply that porosity plays the dominant role in the fatigue crack propagation behaviors of the T6-treated alloy.

In recent decades, grain refiners had not only improved the properties on cast aluminum alloy, but also changed the application field of cast aluminum alloys, which had attracted widespread attention. However, there were few reports on microstructure evolution of A356/CRE Al-X-Ce(Ti, C) system by combining traditional grain refiners with element Ce. In this study, refined A356 alloys with excellent strength and plasticity were obtained by adding CRE Al-X-Ce(Ti, C) (0, 0.4, 0.8, 1.2, 1.6 and 2.0 wt%, respectively). Using XRD, SEM and TEM, the morphology of phases in the refined A356 alloy and phases of grain refiner were identified. The microstructure evolution of α-Al grains and eutectic Si with the introduction of TiC and Ce was analyzed. The results showed that the novel CRE Al-X-Ce(Ti, C) could not only effectively refine α-Al grains, but also modify Si microstructure of the alloy. The refined A356 alloys with excellent strength and plasticity were obtained with 2.0 and 1.6 wt% grain refiner (CRE) additions, respectively. TiC as nucleation particle and Ce as the surfactant refined the α-Al grains. Also, Ce modified eutectic Si by changing the way it grows. When the CRE Al-X-Ce(Ti, C) content researched 2.0 wt%, the long plate-like Al–Si–Ce phase was formed which can easily caused cracks and reduced the elongation of alloy.

Due to the shortage of primary Al resources and significant consumption of Al resources, recycled Al has become a focus of attention. In the process of recycling Al, the Fe element is the most hazardous impurity element, and the coarse Fe-containing phases lead to a reduction in the mechanical properties of recycled Al. In this work, an Al alloy with 1.5 wt% Fe and 0.4 wt% Cr was viewed as a recycled Al, approximately. The continuous rheo-extrusion technique was used to refine the Fe-containing phases in the Al-1.5Fe-0.4Cr alloy, improving the mechanical properties of the alloy. The effect of the extrusion ratio on the microstructure and properties of the continuous rheo-extrusion was investigated. The results showed that, when the extrusion ratio was changed from 4 to 5, the percentage of low-angle grain boundaries in the alloy increased from 45.5% to 53.1%, the average orientation angle reduced from 23.9° to 23.3°, and the grain size decreased from 4.3 ± 0.2 μm to 2.6 ± 0.1 μm. As a result, the ultimate tensile strength, yield strength and elongation of the alloy, with an extrusion ratio of 5, were 161.5 ± 2.8 MPa, 112.3 MPa ± 2.6, and 36.9% ± 1.6%, respectively. Grain refinement and Fe-containing phase refinement were responsible for the improvement in the mechanical properties of the alloy.

In this study, the electrochemical performance and discharge behavior of Mg-Li-Zn-Gd alloys with α-Mg and β-Li-based anode material are investigated, with the aim to improve the anode performance of Mg-air batteries. The experimental anode alloys with detailed Mg-8Li-xZn-yGd (x = 1, 2, 3; y = 1, 2, 3 wt.%) components are prepared, and extrusion deformation is carried out on these alloys. Simultaneously, scanning electron microscope (SEM), X-ray diffractometer (XRD), electrochemical workstation, and constant current discharge systems are applied for microstructure characterization, corrosion, and discharge performance testing. The results show that the experimental alloys are composed of an α-Mg and β-Li dual matrix, with W-Mg3Gd2Zn3, Mg3Gd, and MgLiZn second phases. Meanwhile, extrusion deformation promotes the recrystallization process through the particle-induced nucleation mechanism. The corrosion resistance is improved with the increasing Zn/Gd ratio, and the extruded Mg-8Li-2Zn-1Gd (LZG821) alloy exhibits the optimum corrosion resistance, with a corrosion rate of 0.493 mm·year−1. In addition, the extruded Mg-8Li-1Zn-1Gd (LZG811) alloy has the optimal discharge performance, with a discharge specific capacity of 1371.04 mA·g−1 at a current density of 40 mA∙cm−2, and its anode efficiency reaches nearly 70%. The poorer discharge properties of the Mg-8Li-2Zn-1Gd (LZG821) and Mg-8Li-2Zn-3Gd (LZG823) alloys are attributed to their refined grains, which could bring severe intergranular corrosion while increasing the grain boundary density.

In this study, the mechanical properties and strengthening mechanisms resulting from the evolution of microstructure in an Al-4.39Mg-2.78Zn-0.42Cu (wt%) alloy were investigated through various heat treatment processes. Compared with the conventional T6 process, both the final thermomechanical treatment (FTMT) and the T6+deformation (T6D) process were found to significantly increase the strength of the alloy. In FTMT and T6D treated alloys, the distribution of nano-sized T-Mg32(Al, Zn, Cu)49 phase and dislocations were observed throughout the microstructure. Furthermore, the FTMT process led to a decrease in the solid solution amount of Mg atoms in the alloy, resulting in an improvement of the Portevin-Le Chatelier (PLC) effect. The increase in yield strength of the FTMT-treated and T6D-treated alloys was attributed to the combined effects of enhanced precipitation strengthening and introduced dislocation strengthening. However, the contributions of grain boundary strengthening and solid solution strengthening remained relatively unchanged. This study presents a strategy for producing Al–Mg–Zn–Cu alloys with excellent mechanical performance by manipulating their microstructure and strengthening mechanisms.

A356 alloy is a commonly used casting Al-Si alloy. Because of the excellent fluidity, air-tightness and thermal resistance, it is usually used as castings with complex structure. However, due to the coarse α-Al grains and needle-like phases, the defects including shrinkage cavity and porosity can easily be formed, which reduce the mechanical properties of the castings and lead to the lower safety factor. In this paper, Al-5Ti-0.6C-xCe (x = 0, 0.5, 1.0, 1.5 and 2.0 wt%) master alloys have been prepared by fluorine-salt method combined with the continuous rheological extrusion (CRE) technology. The response of mechanical properties of A356 alloy to the CRE Al-Ti-C-Ce alloys addition upon different Ce contents was investigated. Results showed that, with the increasing Ce content from 0 to 2.0 wt%, the average grain size of α-Al and length of coarse needle-like phases in A356 alloy changed nonmonotonically. When the Ce content was 1.0 wt%, the best refined structure was obtained. The tensile strength, yield strength and elongation of refined A356 by CRE Al-5Ti-0.6C-1.0Ce master alloy were 290.45 MPa, 238.27 MPa and 2.80%, respectively. The introduction of master alloys with different Ce contents promoted the refinement of grain and coarse needle-like phase in A356 alloy, which further improved the mechanical property of the alloy.

In the work, the cryogenic and room temperature drawing behaviors of Cu–Te alloy with a wide range of accumulative drawing true strain up to 1.1 are systematically investigated. For the first time, the storage of geometrically necessary dislocations (GND) and statically stored dislocations (SSD), occurrence of deformation twinning, as well as their respective roles in strain hardening in the drawn Cu–Te alloy at cryogenic and room temperature have been studied. The results show that the liquid nitrogen temperature drawn (LNT-D) Cu–Te alloy presents higher yield strength (YS), ultimate tensile strength than the room temperature drawn (RT-D) Cu–Te alloy. Microstructural investigation reveals that cryogenic wire drawing of Cu–Te alloy promotes the formation of simultaneous twinning and shear bands, accompanied by the fragmentation of Cu2Te phase. The LNT-D Cu–Te alloy exhibits planar slip characteristics, while RT-D Cu–Te alloy presents wave slip characteristics. Compared with RT-D Cu–Te alloy, the higher YS of LNT-D Cu–Te alloy can be mainly attributed to dislocation strengthening and twinning strengthening, which account for 76.25–80.45% and 4.79–4.91% of the total YS respectively. During room temperature drawing, both GND and SSD play an important role in the hardening of Cu–Te alloy. During cryogenic temperature drawing, work hardening is predominantly through rapid multiplication of SSDs.

Abstract Background Lack of opportunity for radical surgery and postoperative tumor recurrence are challenges for surgeons and hepatocellular carcinoma (HCC) patients. This study aimed to develop nomograms to predict recurrence risk and recurrence-free survival (RFS) probability after conversion hepatectomy for patients previously receiving transarterial interventional therapy. Methods In total, 261 HCC patients who underwent conversion liver resection and previously received transarterial interventional therapy were retrospectively enrolled. Nomograms to predict recurrence risk and RFS were developed, with discriminative ability and calibration evaluated by C-statistics, calibration plots, and the Area under the Receiver Operator Characteristic (AUROC) curves. Results Univariate/multivariable logistic regression and Cox regression analyses were used to identify predictive factors for recurrence risk and RFS, respectively. The following factors were selected as predictive of recurrence: age, tumor number, microvascular invasion (MVI) grade, preoperative alpha‐fetoprotein (AFP), preoperative carbohydrate antigen 19-9 (CA19-9), and Eastern Cooperative Oncology Group performance score (ECOG PS). Similarly, age, tumor number, postoperative AFP, postoperative protein induced by vitamin K absence or antagonist-II (PIVKA-II), and ECOG PS were incorporated for the prediction of RFS. The discriminative ability and calibration of the nomograms revealed good predictive ability. Calibration plots showed good agreement between the nomogram predictions of recurrence and RFS and the actual observations. Conclusions A pair of reliable nomograms was developed to predict recurrence and RFS in HCC patients after conversion resection who previously received transarterial interventional therapy. These predictive models can be used as guidance for clinicians to help with treatment strategies.

A semi-solid Al alloy with superior comprehensive performance was obtained via alloying design concept and rheo-diecasting (RDC). The semi-solid alloy slurry was obtained via the vibrating contraction sloping plate. As the contents of Cu and Mg elements increased, the secondary dendrite arm spacing (SDAS) decreased and solubility of Cu and Mg elements increased, which improved the mechanical property and decreased the thermal conductivity of as-cast alloys. The effect of microstructure evolution induced by pouring temperature on mechanical properties at room and elevated temperatures, thermal conductivity, and corrosion behavior of the RDC alloy was investigated. The results demonstrated that the low porosity and refined primary α1-Al grains, secondary α2-Al grains, β-Al5FeSi phases, eutectic Si phases played a significant role in enhancing mechanical properties of the alloy at room temperature. Meanwhile, some submicron β-Al5FeSi phases effectively hindered grain boundary sliding, resulting in the increased mechanical properties of the alloy at elevated temperatures. The improvement in thermal conductivity was related to the decreased electron scattering due to the reduced porosity and small-sized secondary phases. The decrease in the potential difference between the β-Al5FeSi phase and matrix helped improve the corrosion resistance of the alloy.

BackgroundHepatitis B virus (HBV) reactivation is a common complication in hepatocellular carcinoma (HCC) patients treated with chemotherapy or immunotherapy. This study aimed to evaluate the risk of HBV reactivation and its effect on survival in HCC patients treated with HAIC and lenvatinib plus PD1s.MethodsWe retrospectively collected the data of 213 HBV-related HCC patients who underwent HAIC and lenvatinib plus PD1s treatment between June 2019 to June 2022 at Sun Yat-sen University, China. The primary outcome was the risk of HBV reactivation. The secondary outcomes were overall survival (OS), progression−free survival (PFS), and treatment−related adverse events.ResultsSixteen patients (7.5%) occurred HBV reactivation in our study. The incidence of HBV reactivation was 5% in patients with antiviral prophylaxis and 21.9% in patients without antiviral prophylaxis, respectively. The logistic regression model indicated that for HBV reactivation, lack of antiviral prophylaxis (P=0.003) and tumor diameter (P=0.036) were independent risk factors. The OS and PFS were significantly shorter in the HBV reactivation group than the non-reactivation group (P=0.0023 and P=0.00073, respectively). The number of AEs was more in HBV reactivation group than the non-reactivation group, especially hepatic AEs.ConclusionHBV reactivation may occur in HCC patients treated with HAIC and lenvatinib plus PD1s. Patients with HBV reactivation had shorter survival time compared with non-reactivation. Therefore, HBV-related HCC patients should undergo antiviral therapy and HBV-DNA monitoring before and during the combination treatment.

A Cu/AlCoCrFeNi2.1 composite was fabricated via solid-liquid method. In order to acquire the good interface bonding, the pulsed magnetic field (PMF) treatment was applied during the preparation of the Cu/AlCoCrFeNi2.1 composite. The effects of different processes and parameters, including pulse frequency on the interface microstructure, element distribution, diffusion thickness, and mechanical properties of the composite were investigated. The results demonstrated that PMF treatment effectively decreased the diffusion layer thickness of the composite, and improved mechanical properties of the Cu side. The diffusion thickness of the composite reduced from 31.22 μm to 6.20 μm after applying PMF. The action mechanism of PMF during preparation was revealed. The ultimate tensile strength, yield strength, and elongation of the Cu/AlCoCrFeNi2.1 composite via PMF were 192.6 MPa, 121.7 MPa, and 43.8%, respectively, which were higher than that of the composite without PMF. The maximum shear strengths of the composites with and without PFM were 120.2 MP and 137.4 MPa, respectively. When the pulse frequency was 2 Hz, the macro-segregation was eliminated to form the high-quality interface. This work paves a way for the performance improvement and complex parts preparation of layer composite by using PMF.

In present work, typical loading orientations were applied on an Al–Cu–Li single crystal during creep aging, and the relationship between precipitation behavior and loading orientations of the creep-aged Al–Cu–Li single crystal was studied by high angle annular dark field - scanning transmission electron microscope (HAADF-STEM) observation along multiple zone axes. The results show that the precipitation behavior of the precipitates (i.e., T1, θ′) in creep-aged Al–Cu–Li alloy was directly attributed to the loading directions. The number density of T1-phase in the creep-aged single crystal loaded close to α direction is highest, and that of T1-phase is the lowest when the loading direction is α. Moreover, the oriented-precipitation of T1-phase was found in the creep-aged sample loaded close to α direction, while that of θ′-phase was observed in the creep-aged sample loaded close to α direction. The hardness evolution of the creep-aged samples along different loading orientations is also in agreement with the corresponding precipitation behavior. The present work proposes a novel method to regulate the precipitation behavior of the creep-aged Al–Cu–Li alloy by controlling the loading direction, and the ideal loading direction is α for the Al–Cu–Li alloy to obtain better mechanical property.

Al–Cu–Mg–Fe–Ni alloys are widely used in high temperature structural materials such as automobile engine cylinders and pistons, owning to their good high temperature mechanical properties. In this work, the effect of Fe and Ni content, solution treated, and aged process on the microstructure and mechanical properties of Al–Cu–Mg–Fe–Ni alloys were investigated by optical microscopy (OM), scanning electron microscopy (SEM), hardness and tensile tests. Transmission electron microscope (TEM) and high–resolution TEM were used to determine the existence of S phase and Al9FeNi precipitates. The solution treatment followed by aged process is found to be of significant benefit in improving the tensile properties both at room– and elevated temperature.

Background: Hepatocellular carcinoma (HCC) is one of the most malignant cancers and has a poor prognosis. The immune microenvironment is closely related to the drug sensitivity of a tumor. Necroptosis was reported to be a key factor for HCC. The prognostic value of necroptosis-related genes and their association with the tumor immune microenvironment are still unknown. Methods: Necroptosis-related genes that could comprise a signature for predicting the prognosis of HCC cases were identified using univariate analysis and least absolute shrinkage and selection operator Cox regression analysis. The association between this prognosis prediction signature and HCC immune microenvironment was analyzed. The immunological activities and drug sensitivities were compared between different risk score groups identified using the prognosis prediction signature. The expression levels of the five genes comprising the signature were validated using RT-qPCR. Results: A prognosis prediction signature consisting of five necroptosis-related genes was constructed and validated. Its risk score was = (0.1634 × PGAM5 expression) + (0.0134 × CXCL1 expression) − (0.1007 × ALDH2 expression) + (0.2351 × EZH2 expression) − (0.0564 × NDRG2 expression). The signature was found to be significantly associated with the infiltration of B cells, CD4 + T cells, neutrophils, macrophages, and myeloid dendritic cells into the HCC immune microenvironment. The number of infiltrating immune cells and the expression levels of immune checkpoints in the immune microenvironment of high-risk score patients were higher. Sorafenib and immune checkpoint blockade were determined to be ideally suited for treating high-risk score patients and low-risk score patients, respectively. Finally, RT-qPCR results confirmed that the expression levels of EZH2, NDRG2, and ALDH2 were significantly down-regulated in HuH7 and HepG2 cells compared to those in LO2 cells. Conclusion: The necroptosis-related gene signature developed herein can classify patients with HCC according to prognosis risk well and is associated with infiltration of immune cells into the tumor immune microenvironment.

Abstract Background Hepatocellular carcinoma (HCC) is one of the most lethal cancers, with a poor prognosis. Prognostic biomarkers for HCC patients are urgently needed. We aimed to establish a nomogram prediction system that combines a gene signature to predict HCC prognosis. Methods Differentially expressed genes (DEGs) were identified from publicly available Gene Expression Omnibus (GEO) datasets. The Cancer Genome Atlas (TCGA) cohort and International Cancer Genomics Consortium (ICGC) cohort were regarded as the training cohort and testing cohort, respectively. First, univariate and multivariate Cox analyses and least absolute shrinkage and selection operator (LASSO) regression Cox analysis were performed to construct a predictive risk score signature. Furthermore, a nomogram system containing a risk score and other prognostic factors was developed. In addition, a correlation analysis of risk group and immune infiltration was performed. Finally, we validated the expression levels using real-time PCR. Results Ninety-five overlapping DEGs were identified from four GEO datasets, and we constructed a four-gene-based risk score predictive model (risk score = EZH2 * 0.075 + FLVCR1 * 0.086 + PTTG1 * 0.015 + TRIP13 * 0.020). Moreover, this signature was an independent prognostic factor. Next, the nomogram system containing risk score, sex and TNM stage indicated better predictive performance than independent prognostic factors alone. Moreover, this signature was significantly associated with immune cells, such as regulatory T cells, resting NK cells and M2 macrophages. Finally, RT‒PCR confirmed that the mRNA expressions of four genes were upregulated in most HCC cell lines. Conclusion We developed and validated a nomogram system containing the four-gene risk score, sex, and TNM stage to predict prognosis.

Compared with the high pressure diecasting, rheo-diecasting has an advantage in decreasing defects, refining microstructure and improving properties. In the present work, an Al–8Si–0.5Fe alloy with a good combination of mechanical property and thermal conductivity was obtained by rheo-diecasting. The solidification behavior, mechanical properties, and thermal conductivity of the alloy under rheo-diecasting were discussed. The results demonstrated that the chilling effect and shearing vibration not only affected the primary solidification on the vibrating contraction sloping plate, but also the secondary solidification in the remaining liquid during rheo-diecasting. The rheo-diecasting alloy possessed spherical primary α1-Al grains and secondary α2-Al grains, small-sized Al5FeSi phases, eutectic Si phases, and low porosities, and thus exhibited the high mechanical properties and thermal conductivity. With decreasing pouring temperature from 690 °C to 670 °C, the size of primary α1-Al grains, secondary α2-Al grains, Al5FeSi phases and eutectic Si phases was decreased due to high cooling rate, which further improved the mechanical properties and thermal conductivity of the alloy.

For Al–Cu–Mg–Ag alloys, Ω phases play a crucial role in determining the mechanical property at room and elevated temperatures. In this work, an Al–5.5 wt.% Cu alloy with various Mg and Ag contents was prepared by casting and rolling. Combined with microstructure characterization and mechanical property test, the formation and stability of Ω phases and the change in tensile property of alloys due to the increase of Mg and Ag elements were discussed. The results demonstrated that Mg and Ag formed Mg–Ag clusters, which stimulated the precipitation of Ω phases in the Al–5.5 wt.% Cu–0.6 wt.% Mg–0.8 wt.% Ag alloy. As the Mg and Ag content increased to 1.0 wt.% and 1.2 wt.%, respectively, an improvement in stability of Ω phases and an increase in tensile property of the Al–5.5 wt.% Cu–1.0 wt.% Mg–1.2 wt.% Ag alloy were obtained. The tensile strength and elongation of the Al–5.5 wt.% Cu–1.0 wt.% Mg–1.2 wt.% Ag alloy was 533.1 MPa and 8.4%, respectively. In addition, the heat resistance and strengthening mechanisms induced by Ω phases were revealed. The generation of nano-sized Ω phases with a high density resulted in the significant second phase strengthening, thus acquiring the good tensile strength and heat resistant performance in the Al–Cu–Mg–Ag alloy.

Al–Cu–Li bicrystals with different misorientation gradients were prepared to study the effect of misorientation and precipitates on the initial corrosion behavior of the Al–Cu–Li alloy by scanning electron microscopy (SEM), transmission electron microscopy (TEM), immersion testing, and electrochemical testing. The results show that the initial corrosions were generated on the matrix rather than on the grain boundary for the as-quenched alloy. The effect of grain boundary misorientation on the corrosion rates of the as-quenched alloy is very limited. On the other hand, for the aged alloy, the initial corrosions were generated on the grain boundaries, which suffer more severe corrosion than the matrix. Meanwhile, the corrosion of high angle grain boundary (HAGB) is more severe than that of low angle grain boundary (LAGB) for the aged alloy. These results are associated with the high number density of the continuously distributed precipitates on grain boundaries.

To meet the major needs of national defense, transportation, aerospace, and other fields, aluminum alloys with excellent comprehensive performance are continually developed. To reduce the high cost of preparing high-performance aluminum alloys and alleviate the limitations of existing research, the effects of a rolling-drawing coupled deformation on the microstructure-property evolution and strengthening mechanism of 6201 conductive tubes developed by using two different processes were investigated. Subsequently, the evolution of grains, precipitates, texture, and dislocation were examined by performing optical microscopy, scanning electron microscopy, X-ray diffraction, and electron backscattered diffraction. The results showed that the main phases of the investigated tubes were the α-Al matrix, Mg2Si, and Al0.5Fe3Si0.5 second phase. The Al0.5Fe3Si0.5 phase with a face-centered cubic structure functioned as the inhomogeneous nucleation core of Mg2Si. In the rolling process, severe plastic-deformation-induced re-dissolution of the precipitated phases was observed, improving the effect of the subsequent solution treatment and aging treatment. An optimal ultimate tensile strength (UTS) of 341 MPa and electrical conductivity (EC) of 54.12% IACS were successfully obtained in the “extrusion-rolling-solution-aging-drawing” process. Compared with those of the initial tube, these values increased by 136.81% and 41.60%, respectively. However, after the order of rolling and solution treatments was reversed, the UTS and EC of the final tube decreased to 325 MPa and 52.91% IACS, respectively. The microstructure and performance evolution revealed that the uniformly distributed fine Mg2Si phase resulting from the good fit of the processes plays an important role in achieving a higher UTS and EC.

Abstracts: The effects of Sc and Zr on the microstructure and properties of Al–3Fe alloys were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and mechanical property testing. The results show that the Al3(Sc, Zr) phases with a L12 structure are formed with the addition of Sc and Zr, which promotes the heterogeneous nucleation, reduces the segregation and improve columnar grains. In the process of iron-rich phase nucleation and growth, Sc and Zr atoms are adsorbed around iron-rich phases, which prevents the growth of iron-rich intermetallics and makes the needle-like primary Al3Fe phases gradually change to short rod-like, butterfly-like and flower-like morphologies. Additionally, the fibrous eutectic Al6Fe phases are also observed. With increasing the Sc and Zr contents from 0 to 0.35 wt% and 0 to 0.14 wt%, respectively, the strength of the alloy increases and the elongation decreases. The Al–3Fe alloy with the addition of 0.16 wt% Sc and 0.06 wt% Zr has a tensile strength of 160.8 MPa and a yield strength of 132.4 MPa. During aging process, fine, dispersed and coherent nanoscale secondary Al3(Sc, Zr) (L12 structure) phases are formed in the α-Al matrix to promote precipitation strengthening. When the addition of Sc and Zr is 0.35 wt% and 0.14 wt%, respectively, the refinement effect on the macrostructure and the second phase is most obvious. After aging, the tensile strength reaches 233 MPa and the yield strength reaches 200 MPa.

Abstract Background Hepatocellular carcinoma (HCC) remains one of the most common malignant tumors with poor survival. Pyroptosis is a kind of programmed cell death that can regulate the proliferation, invasion, and metastasis of tumor cells. However, the expression levels of pyroptosis-related genes (PRGs) in HCC and their relationship with prognosis are still unclear. Methods Our study identified 35 PRGs through bioinformatics analysis that were differentially expressed between tumor samples and nontumor samples. According to these differentially expressed genes, HCC patients could be divided into two groups, cluster 1 and cluster 2. The least absolute shrinkage and selection operator (LASSO) Cox regression method was performed to construct a 10-gene signature that classified HCC patients in the cancer genome atlas (TCGA) database into low-risk and high-risk groups. Results The results showed that the survival rate of HCC patients in the low-risk group was significantly higher than that in the high-risk group (p < 0.001). The validation cohort, the Gene Expression Omnibus (GEO) cohort, was divided into two risk groups based on the median risk score calculated by the TCGA cohort. The overall survival (OS) of the low-risk group was significantly better than that of the high-risk group (p = 0.007). Univariate and multivariate Cox regression analyses revealed that the risk score was an independent factor in predicting OS in HCC patients. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses showed that immune-related high-risk groups were rich in genes and had reduced immune status. Conclusions PRGs play a significant role in tumor immunity and have the potential capability to predict the prognosis of HCC patients.

A biodegradable metallic ureteral stent with suitable mechanical properties and antibacterial activity remains a challenge. Here we reveal the scientific significance of a biodegradable Mg-Sr-Ag alloy with a favorable combination of balanced mechanical properties, adjustable indwelling time in urinary tract and evident antibacterial activity via in vivo experiments in a swine model. Attributed to the rheo-solidification process, equiaxial microstructure and significantly refined grains (average grain size: 27.1 μm) were achieved. Mg17Sr2 and Mg4Ag were found as the primary precipitates in the matrix, due to which the alloy obtained ca. 111% increase in ultimate tensile strength in comparison to pure magnesium. Both the in vitro and in vivo results demonstrated the satisfactory biocompatibility of the alloy. Histological evaluation and bioindicators analysis suggested that there was no tissue damage, inflammation and lesions in the urinary system caused by the degradation process. The stent also improved the post-operative bladder functions viewed from the urodynamic results. Our findings highlight the potential of this alloy as antibacterial biodegradable urinary implant material.

The effect of Sc-microalloying and Y2O3 nano-particles on the microstructure and mechanical properties of as-cast Al-5.5Si alloy is studied by means of optical microscopy, transmission electron microscopy, hardness test and tensile test. The influence of annealing treatment on the microstructure and properties of the Al-Si alloys is also investigated as well. The results show that the addition of Sc and Y2O3 nano-particles could significantly improve the mechanical property of the Al-Si alloy. The ultimate tensile strength and yield strength of Al-Si-Sc/Y2O3 alloy are improved by around 45 and 71%, respectively, when compared to that of the Al-Si alloy. The effect of the nanosized particles (precipitated and added) on strengthening and deformation of Al-Si alloy is analyzed and discussed in detail. The results of annealing treatment indicate that the change in mechanical property of the Al-Si-Sc alloy during annealing treatment is mainly associated with the precipitation of the secondary Si phase.

In the present work, the influence of stress concentration and deformation temperature on the mechanical behavior of boron carbide particles reinforced aluminum matrix (B4Cp/Al) composites fabricated by powder metallurgy was investigated via the tensile test and finite element simulation based on the real microstructure. The results demonstrate that a uniform particle distribution and a good interface bonding between the particles and matrix are found in the 5 wt% B4Cp/6061Al composite. When the deformation temperature decreases from 298 to 77 K, the tensile property and notch sensitivity ratio of the notched composite increases. Combined with the microstructure observation and stress/strain evolution, the fracture mechanism of the notched composite at 77 K was revealed. Specifically, there is a difference in stress and strain distributions induced by deformation temperature in the initial stage of deformation of the notched composite. The matrix damage tends to occur from the notch and propagate to the high strain regions near the particles. Furthermore, there is a high possibility of particle fracture or interface debonding in the notched composite due to the high matrix stress at 77 K. This work provides the experimental and theoretical basis for the application of particle-reinforced aluminum matrix composites with stress concentration under cryogenic environments.

Background: Combination treatment with tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) has been widely used in patients with unresectable hepatocellular carcinoma (uHCC). As no standard guidelines exist for second-line therapy after failure of combination treatment, this study aimed to determine a better drug-switching strategy.Methods: A total of 785 patients with uHCC who initially received a combination treatment of TKIs and ICIs between January 2017 and December 2021 at our center were screened. After applying the inclusion and exclusion criteria, a total of 102 patients were included in the study. Based on drug switching strategy, patients were divided into a single drug-switching group (A group, n = 49) and a double drug-switching group (B group, n = 53). The comparative effectiveness between groups A and B was assessed based on treatment response and survival time. Second progression-free survival (SPFS) and overall survival (OS) were compared using the Kaplan-Meier method and log-rank test.Results: Compared to group B, group A had a higher overall response rate (16.3% vs. 3.8%; p = 0.0392) and disease control rate (61.2% vs. 49.1%; p = 0.238). The median SPFS in group A was longer than that in group B (5.47 vs. 3.8 months; HR = 1.70, p = 0.0176). In the second-line therapy, the inclusion of lenvatinib resulted in a better SPFS than other TKI treatments (5.53 vs. 2.83 months, p = 0.0038).Conclusion: After the failure of the combination treatment of TKIs and ICIs, single-drug switching significantly prolonged median SPFS in uHCC patients, and retaining lenvatinib resulted in the survival benefit of single-drug switching.

The microstructure is an important factor determining the mechanical properties of A356 alloy. In this experiment, the refiner Al-5Ti-0.6C-1.0Ce master alloys under different preparation temperatures were prepared, and the A356 alloy was refined. The effects of preparation temperature on the number and morphological distribution of each phase in Al-Ti-C-Ce master alloy and the effects of Al-Ti-C-Ce master alloy at different preparation temperatures on the microstructure and mechanical properties of A356 alloy were explored successively. Results showed that, as preparation temperature increased from 850 to 1150 °C, TiAl3 changed from large blocks to long strips and a needle-like phase, and Ti2Al20Ce changed from a bright white block to a broken small block phase. Al-5Ti-0.6C-1.0Ce prepared at 1050 °C can significantly refine the α-Al of A356 alloy and modify eutectic Si. The α-Al grain size was refined from about 1540 to 179.7 μm, and the eutectic Si length was refined from about 22.3 to 17.8 μm with the transition from a coarse needle-like to a short rod-like structure. The ultimate tensile strength and elongation of A356 alloy changed non-monotonically, and the peak values were 282.216 MPa and 3.9% with the Al-Ti-C-Ce preparation temperature of 1050 °C and 950 °C, respectively.

Nano-scaled L phase, β′′ phase, Q′ phase and their composite phases can effectively strengthen Al-Mg-Si-Cu alloys, and balance the mechanical properties and electrical conductivity. However, the re-precipitation behavior and atomic structure of these re-precipitates and the formation and evolution of L phase still need to be further revealed. In this study, the re-precipitation behavior of a representative Al-Mg-Si-Cu alloy at atomic scale is investigated. The alloy samples are successively treated by peak aging, cold deformation and re-aging. The microstructural changes of re-precipitates are found mainly induced by dislocations and Guinier Preston zones formed in the deformation treatment. The re-precipitation process is proved beneficial to simultaneously improve the electrical conductivity and mechanical property. A type of L precursor with sawtooth-like cross section is also discovered. These findings comprehensively reveal the re-precipitation behavior in Al-Mg-Si-Cu alloy and help us to understand the formation and evolution mechanism of L phase more in-depth.

Based on the compositional design concept, an Al–6 Mg–0.8Mn (–0.2Sc) alloy with a good combination of strength and ductility was obtained by hot extrusion deformation with a large extrusion ratio. The microstructure evolution and mechanical property of an Al–6 Mg alloy with adding Mn and/or Sc elements were investigated. The results showed that the addition of Sc element resulted in the grain refinement and promoted the precipitation of nano-sized Al6Mn phases in the Al–6 Mg–0.8Mn–0.2Sc alloy. After hot extrusion, the number of nano-sized Al6Mn phases decreased with the morphology transforming into the rhomboidal/plate-like shape. The combined effect of nano-sized Al6Mn phases and Al3Sc dispersoids offered a strong pinning effect on both grain boundaries and dislocations, leading to a significant refinement for recrystallized grains. Strengthening mechanism analysis indicated that the grain boundary and dislocation strengthening play important roles in enhancing the yield strength of the alloy. In addition, the uniform distribution of solid solution Mg atoms and high recrystallized fraction contributed to the high ductility of the extruded alloy. The aim of this work is to provide a strategy to acquire Al–Mg alloys with excellent mechanical performance.

Compression tests were carried out for hot-rolled Cr–Ti–B low-carbon steels with different Cr contents (low Cr and high Cr) at three strain rates (0.01, 0.1 and 1 s−1) and temperatures ranging from 250 to 650 °C. The serrated flow and dynamic strain aging (DSA) behaviors during deformation were systematically analyzed. The results showed that the effect of the strain rate on serration flow is more obvious than that of the deformation temperature, and the serration type changes from type C to type A with increasing strain rate. The occurrence temperature range of DSA in high Cr steel (350–450 °C) is higher than that in low Cr steel (300–400 °C) at a strain rate of 1 s−1. The activation energy for DSA close to that for the diffusion of carbon, which is considered to produce DSA. A Cr–C cluster is observed in high Cr steel, which clarified that the delaying mechanism throughout the DSA regime is attributed to the pinning of carbon diffusion by Cr atoms.

In this study, the two-phase flow coordination characteristics between α and β phases of H62 brass made by up-drawing continuous casting are investigated based on the upsetting process. An in situ and new research method for two-phase flow is put forward, and the two-phase flow and grain refinement characteristics are observed under different deformation conditions. The results show that α phase flows fast under 400 °C, β phase is pulled and overridden by α phase under this temperature. When the temperature increases to 500 °C, which is higher than β phase transition temperature, the flow velocity of β phase increases, and the deformation of β phase is found to bulge. The flow of β phase is more sensitive to low deformation rates than α phase. The deformation amount has a more significant impact on β phase than α phase, and the deformation of β phase promotes the grain fragmentation and refinement of α phase accompanied by huge β phase bulging obviously. Under the conditions of high temperature, low deformation rate, and large deformation amount, both phase α and β of up-drawing continuous casting brass alloy are broken and the grains are refined. Based on the two-phase flow characteristic, numerical simulation is used to obtain the optimal continuous extrusion parameters of the H-shaped wire of up-drawing continuous casting H62 brass. Then, the optimized complex cross-section wire is prepared by continuous extrusion experiment. This research aims to provide guidance for the complex processing of two-phase alloys.

Background Vessels that encapsulate tumor cluster (VETC) is associated with poor prognosis in hepatocellular carcinoma (HCC). Vessels that encapsulate tumor cluster estimation before initial treatment is helpful for clinical doctors. We aimed to construct a novel predictive model for VETC, using preoperatively accessible clinical parameters and imagine features. Methods Totally, 365 HCC patients who received curative hepatectomy in the Sun Yat-Sen University Cancer Center from 2013 to 2014 were enrolled in this study. Vessels that encapsulate tumor cluster pattern was confirmed by immunochemistry staining. 243 were randomly assigned to the training cohort while the rest was assigned to the validation cohort. Independent predictive factors for VETC estimation were determined by univariate and multivariate logistic analysis. We further constructed a predictive nomogram for VETC in HCC. The performance of the nomogram was evaluated by C-index, receiver operating characteristic (ROC) curve, and calibration curve. Besides, the decision curve was plotted to evaluate the clinical usefulness. Ultimately, Kaplan–Meier survival curves were utilized to confirm the association between the nomogram and survival. Results Immunochemistry staining revealed VETC in 87 patients (23.8%). lymphocyte to monocyte ratio (>7.75, OR = 4.06), neutrophil (>7, OR = 4.48), AST to ALT ratio (AAR > .86, OR = 2.16), ALT to lymphocyte ratio index (BLRI > 21.73, OR = 2.57), alpha-fetoprotein (OR = 1.1), and tumor diameter (OR = 2.65) were independent predictive factors. The nomogram incorporating these predictive factors performed well with an area under the curve (AUC) of .746 and .707 in training and validation cohorts, respectively. Calibration curves indicated the predicted probabilities closely corresponded with the actual VETC status. Moreover, the decision curve proved our nomogram could provide clinical benefits with patients. Finally, low probability of VETC group had significantly longer recurrence free survival (RFS) and overall survival (OS) than the high probability of the VETC group (all P < .001). Conclusion A novel predictive nomogram integrating clinical indicators and image characteristics shows strong predictive VETC performance and might provide standardized net clinical benefits.

Heat treatment is one of the most effective controlling factors used to improve the thermal conductivity (TC) of any alloy castings. In this work, the microstructure of the Al-7Si binary alloy modified by heat treatment at 520 °C for 1−48 h was reported. Both size and shape of the eutectic Si particles are affected by the heat treatment process. Optical microscopy (OM), scanning electron microscopy (SEM) and X-Ray diffraction (XRD) analysis were carried out to characterize the eutectic Si phase transformation. The acicular-shaped eutectic `Si particles were broken into smaller segments and gradually spheroidized. The TC of the alloy heat treated for 12 h increases by 10.5% compared to the as-cast alloy. The correlation between the TC performance and the morphology of eutectic Si phases is detailed discussed.

The microstructure and tensile property of the hypoeutectic Al-Si alloy with and without microalloying of Sc and Zr were studied by means of the optical microscope (OM), Transmission electron microscopy (TEM) and the tensile test. The focus of this work is the effect of microalloying and tensile deformation on the internal structure (i.e. nanoscale precipitates and the stacking faults) in eutectic Si phase. The results show that the nanoscale precipitates are evident in eutectic Si phase in Al-Si alloy without any special heat treatment or modification. The additions of Sc and Zr into the Al-Si alloy increased the size of the nano precipitates, and significantly promoted the formation of the stacking faults inside the eutectic Si phase. Moreover, the eutectic Si phase experienced twinning deformation during the tensile deformation of the Al-Si based alloy, and this twinning deformation was more pronounced with increasing the tensile strength of the Al-Si based alloy. It is proposed that the deformation of the eutectic Si phase also contributed to the property and the ductility of the Al-Si based alloy.

Al-3Fe alloy was prepared by the method of continuous rheo-extrusion, and the effect of rolling deformation on the microstructure and the property of the rheo-extruded Al-3Fe alloy was studied by means of scanning electron microscope (SEM), transmission electron microscopy (TEM) and tensile test. The rheo-extruded pure Al was also prepared for comparison. The results showed that the rolling deformation could further refine the grain size of the rheo-extruded Al-Fe alloy, and reduce the size of the Al-Fe phase. Due to the present of nanosized and sub-micron sized Al3Fe phase, the strength of rheo-extruded Al-Fe alloy is significantly higher than that of rheo-extruded pure Al, and this advantage has been maintained during subsequently rolling deformation. Moreover, the strength and the elongation are simultaneously increased when the rolling reduction exceeds 60% for Al-Fe alloy and pure Al. Both of Al-Fe alloy and pure Al have the best comprehensive mechanical property when the rolling reduction reaches 90%. The main contribution is attributed to the grain refinement and the formation of high fraction substructure. Keywords: Al alloy, Rheo-extrusion, Deformation, Microstructure, Property

Modern industrial development has put forward higher demands on the performance of metallic structural materials, especially in terms of light weight, high strength and corrosion resistance. All of these characteristics are of particular importance in transportation fields. As one of the most representative structural materials, aluminum and alloys have exhibited significant advantages in light weight. Most of the alloys are prominently featured in one specific aspect. The overall performance still needs to be improved. In recent years, researchers have developed Al-Mg-Zn(-Cu) alloy, a new wrought aluminum alloy, whose design strategy is known as “crossover alloying”. This novel alloy is an age-hardened Al-Mg alloy with a T-Mg32(Al, X)49 (X is Zn, Cu) phase as the main strengthening phase. This system of alloys exhibits excellent properties in terms of strength and corrosion resistance, which makes it promising for applications in automotive, marine, aerospace and other fields. This paper summarizes the research progress of Al-Mg-Zn(-Cu) alloy, and analyzes the basic methods of microstructural control in terms of composition design and property research. Finally, the future directions of this alloy are proposed.

Nanostructuring of metals is nowadays considered as a promising strategy towards the development of materials with enhanced electrochemical performance. Porous and fully dense CuNi films were electrodeposited on a Cu plate by electrodeposition in view of their application as electrocatalytic materials for the hydrogen evolution reaction (HER). Porous CuNi film were synthesized using the hydrogen bubble template electrodeposition method in an acidic electrolyte, while fully dense CuNi were electrodeposited from a citrate-sulphate bath with the addition of saccharine as a grain refiner. The prepared films were characterized chemically and morphologically by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The Rietveld analysis of the XRD data illustrates that both CuNi films have a nanosized crystallite size. Contact angle measurements reveal that the porous CuNi film exhibits remarkable superhydrophobic behavior, and fully dense CuNi film shows hydrophilicity. This is predominately ascribed to the surface roughness of the two films. The HER activity of the two prepared CuNi films were investigated in 1 M KOH solution at room temperature by polarization measurements and electrochemical impedance spectroscopy (EIS) technique. Porous CuNi exhibits an enhanced catalysis for HER with respect to fully dense CuNi. The HER kinetics for porous film is processed by the Volmer–Heyrovsky reaction, whereas the fully dense counterpart is Volmer-limited. This study presents a clear comparison of HER behavior between porous and fully dense CuNi films.

Magnetic chitosan hydrogel has aroused immense attention in recent years due to their biomedical significance and magnetic responsiveness. Here, A new electrodeposition method is reported for the fabrication of a novel CuNi-based magnetic chitosan freestanding film (MCFF) in an acidic chitosan plating bath containing SDS-modified CuNi NPs. Contrary to chitosan’s anodic and cathodic deposition, which typically involves electrochemical oxidation, the synthetic process is triggered by coordination of chitosan with Cu and Ni ions in situ generated by the controlled surface dissolution of the suspended NPs with the acidic plating bath. The NPs provide not only the ions required for chitosan growth but also become entrapped during electrodeposition, thereby endowing the composite with magnetic properties. The obtained MCFF offers a wide range of features, including good mechanical strength, magnetic properties, homogeneity, and morphological transparency. Besides the fundamental interest of the synthesis itself, sufficient mechanical strength ensures that the hydrogel can be used by either peeling it off of the electrode or by directly building a complex hydrogel electrode. Its fast and easy magnetic steering, separation and recovery, large surface area, lack of secondary pollution, and strong chelating capability could lead to it finding applications as an electrochemical detector or adsorbent.

Thermomechanical treatment consisting of heat treatment and deformation is an effective processing route for precipitation-hardened 6xxx alloy (Al-Mg-Si-Cu system), and precipitates and dislocations produced during the process can significantly change its mechanical and conductive performance. We therefore investigated the microstructural evolution of precipitates in a representative 6xxx alloy during thermomechanical treatment. When the precipitates encountered the accumulated dislocations, the precipitates were bent and broken into dispersed smaller particles. The strength of the alloy was significantly improved by the proliferation of dislocations and precipitates and desired electrical conductivity was obtained as well. Our results prove that peak aging plus cold rotary swaging is an efficient processing route for simultaneously improving the mechanical and conductive performance of 6xxx alloy.

This study aimed to identify aberrantly methylated differentially methylated CpG sites (DMCs) and investigate their prognostic value in hepatocellular carcinoma (HCC). A total of 2,404 DMCs were selected from Gene Expression Omnibus (GEO) and validated by The Cancer Genome Atlas (TCGA). The TCGA cohort was divided into a training cohort and a validating cohort. First, the prognostic model based on six DMCs, including cg08351331, cg02910574, cg09947274, cg17589341, cg24652919, and cg26545968, was constructed based on the least absolute shrinkage and selection operator (LASSO) regression Cox analysis. The area under the curve (AUC) of the DMC-based model was 0.765 in the training cohort and 0.734 in the validating cohort. The accuracy of a model combining the DMC signature and American Joint Committee on Cancer (AJCC) stage, with an AUC of 0.795, was better than that of the DMCs or AJCC stage alone. Second, further analysis revealed that the methylation rate of cg08351331 was negatively associated with the expression of its relative gene, lipopolysaccharide-binding protein (LBP). Besides, the gene expression of LBP was significantly associated with poor overall survival in patients with hepatitis B virus (HBV) infection. Finally, these findings were confirmed by GSE57956 data and our own cohort. In conclusion, we established an accurate DMC-based prognostic model that could be combined with AJCC stage to improve the accuracy of prognostic prediction in HCC. Moreover, our preliminary data indicate that LBP may be a new key factor in HBV-induced HCC initiation through the regulation of its methylation.

Ni-based bimetallic films with 20 at.% and 45 at.% Cu and mesostructured surfaces were prepared by electrodeposition from an aqueous solution containing micelles of P123 triblock copolymer serving as a structure-directing agent. The pH value of the electrolytic solution had a key effect on both the resulting Cu/Ni ratio and the surface topology. The catalytic activity of the CuNi films toward hydrogen evolution reaction was investigated by cyclic voltammetry (CV) in 1 M KOH electrolyte at room temperature. The Cu45Ni55 film showed the highest activity (even higher than that of a non-mesostructured pure Ni film), which was attributed to the Ni content at the utmost surface, as demonstrated by CV studies, as well as the presence of a highly corrugated surface.

In this work, based on the A356 alloy, a novel Al–Si–Mg–Cu–Fe–Sr alloy with good mechanical property and high thermal conductivity was developed. The semi-solid slurry of the alloy was prepared via the vibrating contraction inclined plate. The microstructure evolution and solidification behavior of the alloy were investigated. The results demonstrated that, compared with the A356 alloy, the enhanced property of the Al–Si–Mg–Cu–Fe–Sr alloy was associated with the size of primary α-Al grains and morphology of eutectic Si phases. In addition, the preparation process parameters of semi-solid slurries, including the pouring temperature, inclination angle, and vibration frequency, had a crucial effect on the size and morphology of primary α-Al grains. The optimized pouring temperature, inclination angle, and vibration frequency were 670 °C, 45°, and 60 Hz, respectively. In this condition, for the primary α-Al grains, a minimum grain diameter of 64.31 µm and a maximum shape factor of 0.80 were obtained. This work provides a reference for the application of the alloy with high performance in the field of automobile and communication.

Alternative splicing (AS) has a critical role in tumor progression and prognosis. Our study aimed to investigate pancreatic cancer-specific AS events using RNA-seq data, gaining systematic insights into potential prognostic predictors. We downloaded 10,623 genes with 45,313 pancreatic cancer-specific AS events from the Cancer Genome Atlas (TCGA) and SpliceSeq database. Cox univariate analyses of overall survival suggested there was a remarkable association between 6,711 AS events and overall survival in pancreatic cancer patients (P < 0.05). The area under the curves (AUC) of the receiver operator characteristic curves (ROC) of risk score was 0.89 for final prognostic predictor. Results indicated that AS events of DAZAP1, RBM4, ESRP1, QKI, and SF1 were significantly associated with overall survival. The results of FunRich showed that transcription factors KLF7, GABPA, and SP1 were the most highly related to survival-associated AS genes. Furthermore, using DriverDBv2, we identified 13 driver genes associated with survival-associated AS events, including TP53 and CDC27. Thus, we concluded that the aberrant AS patterns in pancreatic cancer patients might serve as prognostic predictors.