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The present study investigates the corrosion behavior of a Mg–Zn–Ca–La alloy. Results indicate that the corrosion resistance is enhanced by rolling deformation and subsequent annealing treatment significantly. The microstructure, distribution of second phase and grain orientation are the main factors affecting corrosion properties. The second phase with semi-continuous network in the as-cast alloy gives rise to the penetration of corrosion into the matrix. However, the dispersed second phase after deformation results in uniform corrosion. The formation of dense corrosion layer at the initial stage of corrosion is favorable for the improvement of corrosion resistance. The sample with 〈0001〉 plane oriented towards surface exhibits good corrosion resistance, which is ascribed to the homogeneous microstructure and strong basal texture.

The effects of aging treatment on corrosion properties of an extruded Mg-8.9Gd-2.8Y-1.8Zn-0.4Zr-0.2Ca (wt.%) alloy were investigated. The as-extruded alloy was consisted of un-dynamically recrystallized region containing lamellar long period stacking ordered (LPSO) phase and block-shaped LPSO phase, finely recrystallized grains and small amounts of Mg-RE phase. After aging treatment, part of lamellar LPSO phases was dissolved into the matrix and replaced by recrystallized grains. The size of recrystallized grain was increased from 1.8 μm for the as-extruded sample and to 3.5 μm for the peak-aged sample. Corrosion tests indicated that aging treatment effectively improved the corrosion resistance of the as-extruded Mg-8.9Gd-2.8Y-1.8Zn-0.4Zr-0.2Ca (wt.%) alloy. The lamellar LPSO phases with a low potential were preferentially corroded, and the homogeneous microstructure of the peak-aged sample effectively reduced the possibility of micro-galvanic corrosion. Hence, the peak-aged sample with a more homogeneous microstructure and small amount of lamellar LPSO phase showed a better corrosion resistance.

The present study investigated anisotropy in tensile behavior of an extruded Mg-4.50Zn-1.13Ca (wt.%) alloy through tensile testing along different tilt angles relative to the extrusion direction. Results showed that the as-extruded Mg-4.50Zn-1.13Ca (wt.%) alloy exhibited anisotropy in tensile behavior due to the formation of basal texture. Basal slip, prismatic slip and tensile twinning were the dominant deformation modes depending on the tensile direction. Prismatic slip was the dominant deformation mode for samples with small tilt angle (θ = 0° and 22.5°). Basal slip was activated when the tilt angle was increased, which also resulted in the decrease of yield strength. Tensile twinning was responsible for the yielding of the samples with high tilt angles (θ = 67.5° and 90°). The ductility was significantly reduced at high tilt angle, which was mainly attributed to the appearance of tensile twinning during tensile deformation.

Titanium nitride (TiN) is widely used in electrode materials in fast charging/discharging supercapacitors (SCs) due to its outstanding conductivity. However, the low capacitance of the TiN electrode limits its further application in the SCs. Therefore, the reasonable design of the TiN electrode with high electrochemical and mechanical properties is still a challenge. In this paper, the silicon nanowires/titanium nitride electrode (Si NWs/TiN) is prepared by depositing TiN onto the etched Si nanowires by direct current magnetron sputtering. The Si NWs are prepared by etching silicon in 4.8 M HF/0.02 M AgNO3 aqueous solution for different times (5 min, 15 min, 30 min, 60 min). The mechanism of the effect of etched silicon substrate morphology on the electrochemical performance of Si NWs/TiN electrode was studied. As the etching time increases, the differences of the TiN surface structure, lattice defects and surface chemical composition will change the capacitance performance and charge storage mechanism of the Si NWs/TiN electrode. The prepared Si30 NWs/TiN electrode exhibits an outstanding specific capacitance as high as 113.55 F g−1 at a scan rate of 5 mV s−1 with 0.5 M H2SO4 solution as electrolyte. The specific capacitance of the Si30 NWs/TiN electrode is as high as 7.5 times that of the electrode without etching at 100 mV s−1. The Si30 NWs/TiN electrode has an excellent cyclic stability performance, which the electrode has a decay rate of 12.4% after 2000 cycles. This indicates that the electrode has reliable stability. The electrode of the supercapacitor prepared by this method can open up a new way to expand the specific surface area of other transition metal nitride.

Thickness and specific surface area of the film electrode are critical parameters for supercapacitors. The relationship between the thickness and the specific surface area of the film directly affects the capacitance and electrochemical stability performance of super supercapacitors, which virtually affects the contact chance of ion in the electrolyte on the surface of electrode and the ion transport path of electrode. In this paper, the CrN thin films with a thickness of 200–3500 nm are prepared using direct current magnetron sputtering. Atomic force microscopy (AFM) technique is introduced to investigate the relationship between thickness and the specific surface area of the CrN films. The electrochemical performances of CrN electrode with the nanoporousper structure is analyzed in different electrolytes H2SO4, Na2SO4 and NaCl aquous solutions. The specific surface area of the film increases linearly with the film thickness increases. The areal capacitance is also linearly related to the specific surface area. The spurtted CrN film with a thickness of 3370 nm has a specific surface of up to 43.59 cm2 per cm2 footprint area. Its areal and volume capacitances reache to 53.92 mF cm−2 and 650 F cm−3 at 5 mV s−1, respectively. In addition, the areal capacitance of CrN film electrode with 655 nm possesses reaches to 40.53 mF cm−2 for 0.5 M H2SO4 solution, 32.69 mF cm−2 for 0.5 M Na2SO4 solution and 9.17 mF cm−2 for NaCl solution at a scan rate of 5 mV s−1. Furthermore, the CrN film electrode exhibits excellent capacitance retention of 95.3%, 93.8% and 89.9% in H2SO4, Na2SO4 and NaCl electrolytes, respectively, after 2000 cycles. Therefore, the sputtered CrN thin film is an potential electrode material for electrochemical supercapacitors.

The mechanical properties of an Mg–Zn–Ca alloy were significantly improved through extrusion deformation. High-density spheroidal Ca2Mg6Zn3 with a diameter ranging from 10 to 50 nm dynamically prec...

The evaluation of cell's weatherability is of practical interest. To further improve the soluble lead flow battery's weatherability, physiochemical properties of electrolytes containing fluoborate, perchlorate, methanesulfonate and trifluoromethanesulfonate are investigated from −60 to 50 °C. Activities of CF3SO3H and HClO4 are poor in trifluoromethanesulfonate and perchlorate solutions due to common anion effect. The solubility of lead salt can be improved by increasing temperature, but worsened by increasing acid's content. With the temperature increasing, the conductivity is enhanced, and the viscosity is lowered for four solutions. The same results have been found by increasing acid's content except for CF3SO3H. The high energy efficiency can be achieved for cells over −40–0 °C using fluoborate and perchlorate solutions, 73.2% at −40 °C and 78.1% at −30 °C respectively. Over the temperature range of 20–50 °C, the cells with methanesulfonate and trifluoromethanesulfonate solutions have good performance, 77.4% and 73.7% at 50 °C respectively.

In this work, the Metal-rich phase Chromium Aluminum (CrAl)/Ceramic phase Chromium Aluminum Nitride (CrAlN) multi-layer coatings were prepared by Arc Ion Plating (AIP). The micro-structure and phase composition of CrAl/CrAlN multi-layer coatings were characterized, and the microstructure, mechanical properties, residual stress and fracture toughness of the coating were emphatically analyzed. It has been found out that the residual stress of the multi-layer coating was only −0.932 ± 0.065 GPa, which was significantly lower than that of the mono-layer coating for −1.569 ± 0.093 GPa. At the same time, it was also found that the preferred growth orientation of the coating changed from a mono-layer (111) to a multi-layer (200) crystal plane. The hardness of the multi-layer (22.74 ± 0.57 GPa) is slightly lower than that of the mono-layer (24.92 ± 0.5 GPa), and the adhesion strength (46.2 ± 3.8 N) is obviously higher than that of the mono-layer (37.4 ± 2.4 N), and the fracture toughness is also higher (8.7 ± 0.8 MPa m1/2). In addition, the mechanism of crack initiation and propagation in stress-induced coatings was studied in detail on the basis of the structure of micro-nano CrAl/CrAlN multi-layer coatings.

Directionally solidified Al2O3/SmAlO3 (SAP) eutectic ceramics were successfully prepared with an optical floating zone furnace. The crystallographic orientation and interfacial structures were investigated by electron backscattered diffraction and transmission electron microscopy. It was found that Al2O3 has one preferred growth direction but the SAP has two. The preferred growth direction of the directionally solidified Al2O3/SAP eutectic ceramics was 〈10 1 ¯ 0〉Al2O3 || 〈100〉SAP || 〈011〉 SAP. The near-coincidence site lattice models were proposed to interpret the intergrowth of the two SAPs. It was found that the two interfaces have nearly the same volume strain, validating the coexistence of both orientation relationships.

Titanium nitride (TiN) films were generated in the abnormal glow discharge (AGD) region and the glow-arc transition discharge (GATD) region by varying target current density (Ja) in an Ar/N2 atmosp...

The microstructural homogeneity of austempered ductile iron (ADI) with different graphite counts was evaluated by microstructural observations and hardness measurement. ADI was composed of spheroidal graphite, ausferrite, and stabilized austenite. Microstructural observation and microhardness evaluation indicated that graphite nodule counts affected the microstructure significantly, in a sense that the microstructure was more homogeneous for samples with higher graphite counts. More graphite nodules provided more positions for ferrite nucleation and gave rise to a fine ausferrite microstructure. However, for samples with fewer graphite nodules, the diffusion of carbon atoms in austenite far away from graphite was inhibited, which stabilized the austenite and gave rise to the existence of large-size blocky austenite. Consequently, ADI with high graphite nodule count exhibited superior ductility. This study suggested that more graphite nodule is preferred in ADI to obtain a more homogeneous microstructure.

Large size, high-density (99.97%) and well-organized Al2O3/Y3Al5O12 (YAG) eutectic ceramics were prepared by the modified Bridgman method. The evolution of the three dimensional microstructure and micropores were investigated. The diameter of the micro-pores and the porosity decreased during directional solidification. The average equivalent diameter of the micro-pores was 2.41 μm in the well-prepared eutectic ceramics. Most of the pores (98.07%) were smaller than 4 μm. These data are comparable to those prepared by the optical floating zone method. The as-grown eutectic ceramics were polycrystalline, but the interfaces were well-bonded and there were no amorphous phases in the microstructure. The misfits of the different crystallographic relationships were calculated, and the bottleneck of the single-crystal preparation was identified. These results could provide theoretical guidance for the preparation of large, single-crystal Al2O3/YAG eutectic ceramics by the modified Bridgman method.

Natural bio-ceramics have attracted extensive interests due to its high strength and high toughness, which can hardly be achieved in artificial ceramics simultaneously. In this work, the microstructure and properties of the wild boar's tusk enamel were investigated. The enamel was found to exhibit a hierarchical structure ranging from the hydroxyapatite (HAP) fibers (single or poly-crystals, nano-scale), enamel rods (micro-scale), enamel types (meso-scale) to enamel patterns (macro-scale). It is worth mentioning that the high-density and high-order hierarchical nanotwins were observed in the HAP fibers. The mechanical properties of the wild boar's tusk enamel showed strong anisotropy and were higher along the longitudinal direction than along the transverse direction. The mechanical properties varied from the dentin-enamel junction (DEJ) to the outer surface. The elastic modulus increased with the distance from the DEJ and then kept invariant. The nano-hardness increased in inner enamel but decreased in outer enamel. There was a peak of nano-hardness in inner enamel area. The fracture toughness showed an opposite tendency. It exhibited high values in inner enamel, but fell in the outer enamel zone. The irregular, decussating texture of the enamel, as well as the nanotwins/hierarchical nanotwins was considered as the main reason for its excellent mechanical properties. These unique structures of the wild boar's tusk enamel are expected to cast light on the design of medical materials and provide some guidelines to improve their mechanical properties.

Plasma electrolytic oxidation (PEO) was carried out on AZ91 and WE43 Mg alloys in phosphate electrolyte. The effects of β-phases on growth behaviors of PEO coatings formed on two Mg substrates were analyzed and compared. Results showed that PEO coatings developed heterogeneously in two Mg substrates due to the existence of β-phases. Before discharge breakdown, conversion film initially grew on α-Mg matrix and spread to β-phase (Mg17Al12) in AZ91 alloy, while it preferentially formed around β-phase (Mg14Nd2Y) rather than α-Mg matrix in WE43 alloy. This was attributed to the different reactivity of β-phases in two Mg alloys. After discharge breakdown, the micro-pores in PEO coatings grew on β-phases were larger in size as compared with that on α-Mg matrix. With the treated time, the inhomogeneous growth of PEO coatings disappeared gradually and PEO coatings became uniform. Finally, β-phases did not destroy the continuity of PEO coatings.

The dynamic precipitation behavior of a Mg-Zn-Ca-La alloy during deformation has been investigated. A large amount of fine precipitates was detected after deformation, indicating that dynamic precipitation occurred. The precipitates at the grain boundaries included Ca2Mg6Zn3 and Mg4Zn7, whereas the intergranular precipitates were mainly Mg4Zn7. Ca, which has a large atomic radius, preferred to segregate to grain boundaries, where it resulted in the formation of Ca2Mg6Zn3. Zn, which has a similar diffusion coefficient to Mg, resulted in Mg4Zn7 being distributed around the matrix. The stability of the Mg4Zn7 phase was enhanced in the as-extruded Mg-Zn-Ca-La alloy. The grain-boundary precipitates acted as effective obstacles to grain growth, giving rise to the formation of a refined microstructure. The intragranular Mg4Zn7 precipitates hindered the mobility of dislocations, improving the mechanical properties. Additionally, a high density of ultrafine nanoparticles was detected in the un-dynamically recrystallized (DRXed) region, being related to the high density of dislocations therein.

Long non‐coding RNAs (lncRNAs) are a novel class of regulators in multiple cancer biological processes. However, the functions of lncRNAs in pancreatic ductal adenocarcinoma (PDAC) remain largely unknown. In this study, we identified PWAR6 as a frequently down‐regulated lncRNA in PDAC samples as well as a panel of pancreatic cancer cell lines. Down‐regulated PWAR6 was associated with multiple clinical outcomes, including advanced tumour stage, distant metastasis, and overall survival of PDAC patients. In our cell‐based assays, ectopic expression of PWAR6 dramatically repressed PDAC cells proliferation, invasion and migration, accelerated apoptosis, and induced cell cycle arrest at G0/G1 phase. In contrast, depletion of PWAR6 mediated by siRNA exhibited opposite effects on PDAC cell behaviours. In vivo study further validated the anti‐tumour role of PWAR6 in PDAC. By taking advantage of available online sources, we also identified YAP1 as a potential PWAR6 target gene. Negative correlation between YAP1 and PWAR6 expressions were observed in both online database and our PDAC samples. Notably, rescue experiments further indicated that YAP1 is an important downstream effector involved in PWAR6‐mediated functions. Mechanistically, PWAR6 could bind to methyltransferase EZH2, a core component of Polycomb Repressive Complex 2 (PRC2) in regulating gene expression, and scaffold EZH2 to the promoter region of YAP1, resulting in epigenetic repression of YAP1. In conclusion, our data manifest the vital roles of PWAR6 in PDAC tumorigenesis and underscore the potential of PWAR6 as a promising target for PDAC diagnosis and therapy.

Severe shot peening (SP) was performed on the AZ31 and AZ91 Mg alloys to obtain a nanostructured surface layer. The microstructure, micro-hardness and corrosion behavior of AZ31 and AZ91 Mg alloys after SP treatment were studied using transmission electron microscopy, micro-hardness tester and corrosion tests, respectively. Results showed that SP treatment produced a plastic deformation layer with α-Mg grains at the nanometer scale in the surface of AZ31 and AZ91 Mg alloys. After SP treatment, the micro-hardness in the near surface region displayed an obvious increase for two alloys, owing to the combination of the grain refinement and the work-hardening. The corrosion resistance of AZ31 alloy was improved by SP treatment, because a relatively compact passive film formed rapidly on the nanostructured surface. Unfortunately, SP treatment played a minor role in enhancing the corrosion resistance of AZ91 alloy, because it had little effect on size and distribution of β-phases.

Magnetron sputtering was used to deposit (Ti, Al)N films with different Al/Ti atomic ratios by changing the current of the Al target and to study their tribological properties. The phase composition, microstructure and elemental distribution of films were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS). The influence of the ratio between Al and Ti atoms on the tribological properties and the mechanical properties of the films was analyzed. The conclusions showed that there was a tendency for films to shift from the crystalline to the amorphous state as the Al/Ti atomic ratio increases. Herein, changes in film microhardness were related to the substitution relationship between Ti atoms and Al atoms. Especially, when the Al/Ti atomic ratio was 0.54, coefficient of friction (COF) and specific wear rate were the lowest. Compared with TiN film, (Ti, Al)N films have higher microhardness due to the solid solution hardening caused by the substitution between Al and Ti atoms to produce lattice distortion. These factors make films have excellent tribology performance.

To improve the deposition rate of thin films, a novel oscillating pulse magnetron sputtering technology (OPMS) was developed to substitute the traditional high-power impulse magnetron sputtering (HiPIMS). Meanwhile, the relative density and the mechanical properties were also significantly enhanced by this method. In this study, OPMS was used to prepare the pure Cu film, and the effect of the target current on the mode of copper atoms leaving the target (off-target method) under argon gas atmosphere was also investigated. The results showed that with the increase of the target current, the off-target method of copper atoms was transformed from sputtering to evaporation, the surface cracks’ width of the deposited films gradually decreased, and the lattice constants of the Cu films were close to the bulk materials. Furthermore, the deposition rate of Cu films obviously increased from 19 to 103 nm/min. The crystal structures of Cu films showed a face-centered cubic structure, and the grain size increased from 13 to 18 nm, with the target current increased from 2 to 18 A. Moreover, Cu films deposited at currents of 8 and 13 A exhibited excellent adhesion.

The weatherability of soluble lead flow battery is critical to its large-scale and safety application. In this work, physicochemical properties of PbO2 deposits are investigated at different temperatures, 50, 20, 0 and -20 °C. The deposit formed at low temperature has the higher discharge capacity than that formed at high temperature when they are discharged at the same temperature of 20 °C. With the temperature decreased from 50 to -20 °C, the relative content ratio of α-PbO2: β-PbO2 changes from 0: 100 to 33: 67. The non-stoichiometric ratio of Olattice: Pb in PbO2 deposits increases from 1.31 ± 0.15 to 1.67 ± 0.18. And particle sizes of PbO2 deposits become fine, from 4.29 ± 1.71 to 2.08 ± 0.93 µm, and their distributions become narrow. This indicates that physicochemical properties of PbO2 deposits can be improved by increasing activation overpotential through decreasing temperature. However, the cycling performance of batteries becomes worse at low temperature, even though the high activity PbO2 deposits is obtained after charge. It can be well explained from the limiting current-density and exchange current density of positive electrode significantly decreases with decreasing temperature.

Micro arc oxidation (MAO) coatings doped with graphene oxide (GO) were prepared on pure titanium by adding GO and sodium dodecyl benzene sulfonate (SDBS) into a sodium silicate solution. The as-deposited coatings were comparatively analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The binding forces of the MAO, MAO+GO and MAO+GO+SDBS three coatings were measured by a scratch tester. The mechanical property of the three coatings was analyzed using the nano-indentation technique. The corrosion resistance of the coatings was tested by the electrochemical system in 3.5% NaCl solution. The photocatalytic activity of the prepared samples was evaluated by determining the degradation of methylene blue (MB) solution. The results showed that compared to the MAO coating, the morphologies and phase compositions of MAO+GO and MAO+GO+SDBS composite coatings were significantly different. These two composite coatings all had superior photocatalytic activity. Especially, the MAO+GO composite coating still had enhanced binding force and excellent corrosion resistance. Furthermore, the relationship between the microstructure and the properties of these three MAO coatings was analyzed.

Long non-coding RNAs (lncRNAs) function as vital regulators of the progression of various diseases, particularly cancers. In the present study, utilizing the Cancer Genome Atlas (TCGA) data set and a series of cell experiments and clinical tissue samples assays, we found that LINC00662 expression was significantly up-regulated in gastric cancer (GC) tissues and cell lines. High expression of LINC00662 predicted poor prognosis compared to in patients showing low expression. Knockdown of LINC00662 expression decreased GC cell proliferation and increased the chemo-sensitivity of GC cells. Further, we demonstrated that knockdown of LINC00662 suppressed the Hippo-YAP1 signaling pathway in GC cells. Mechanistically, LINC00662 regulated YAP1-mediated GC cell proliferation by sponging miR-497-5p. Overall, our results revealed a critical role for the LINC00662-miR-497-5p-YAP1 axis in GC cell growth, providing a new target for GC.

The microstructure and texture evolution of Mg-Zn alloy during recrystallization was investigated by EBSD in the present study. Deformed region, fine DRXed region and coarse DRXed region were obtained in Mg-Zn alloy during deformation. It was found that the texture intensity in DRXed region was weaker compared with the deformed region. The second phase at grain boundaries resulted in the formation of fine DRXed grains with weaker texture compared with the coarse DRXed region. Additionally, a remarkable grain-size driven textural transition from ⟨10.0⟩–⟨11.0⟩ texture to ⟨11.0⟩ texture were detected with the growth of DRXed grains. The recrystallized grains with small grain size showed a fiber texture distributing homogeneously between ⟨10.0⟩ and ⟨11.0⟩, while ⟨11.0⟩ fiber texture was predominant for the large recrystallized grains. It is suggested that ⟨11.0⟩ oriented grains grew faster than other oriented grains, which was ascribed to larger misorientation between ⟨11.0⟩ oriented grains and their neighboring grains.

In order to study the spontaneous escape behavior of silver in ion plating coatings and its inhibition mechanism, a series of silver-doped titanium nitride coatings were prepared by magnetron sputtering. The effect of cluster interface structure on the spontaneous escape behavior of silver in ion plating coatings were observed, and various thicknesses of homogenous silver-free barrier layers were explored to achieve the permanent retention of silver. Results showed that for silver-doped titanium nitride coatings prepared with the silver target current increased from 0.01 A to 0.2 A, more spontaneously escaped silver particles were observed at the cluster interface of the coating and were far from being crystallized into a layered structure. Approximately 500 nm pure titanium nitride surface cover could achieve the permanent retention of silver in titanium nitride coatings with a high dopant content of silver. The cluster interfaces of the titanium nitride coating interdigitated with each other to form a dendritic network structure. The interdigitated dendritic network structure blocked the spontaneous escape of silver and achieved the permanent retention of silver in the titanium nitride coating.

YAP1, a vital effector of Hippo pathway, promotes cancer development via transcriptionally regulating a batch of target genes involved in various signaling pathways, including proliferation, apoptosis, and cell drug sensitivity. Recently, circular RNAs (circRNAs) have been shown to control gene expression post-transcriptionally and become a new layer of gene regulation. However, whether circRNAs play roles in YAP1-induced tumorigenesis is still largely elusive. Here, we identify circRNA-000425 as a new inhibitory target of YAP1, and also find that it binds to miR-17/miR-106b, and thus suppresses cancer cell growth induced by these miRNAs. circRNA-000425 is revealed as a YAP1 target through circRNA microarray analysis of RNAs extracted from cells treated with or without YAP1 siRNAs, and further confirmed by RT-q-PCR and ChIP assays. Interestingly, bioinformatics analysis, luciferase assay, and RT-q-PCR results showed that circRNA-000425 binds to miR-17 and miR-106b, but not let-7a, and rescues the inhibitory effect of miR-17/miR-106 on the expressions of both p21 and BIM. In addition, colony formation and MTT assay showed that circRNA-000425 inhibits cancer cell growth induced by miR-17. These findings reveal a mechanism by which YAP1 promotes oncogenic activities of miR-17 and miR-106b through transcriptionally inhibiting circRNA-000425 expression.

The hot deformation behavior and processing characteristics of Mg–3Zn–0.3Ca–0.4La (wt%) alloys were investigated by hot compression deformation. The results suggested that deformation parameters had significant effects on deformation behavior and dynamic recrystallization of the Mg–Zn–Ca–La alloy. The average activation energy of deformation was calculated to be 188.9 kJ/mol. The processing map was constructed and analyzed based on the dynamic material model, and the optimum hot working window of the alloy was determined to be the temperature of 350 °C and the strain rates between 0.001 and 0.01 s−1. Furthermore, the DRX kinetic model of the Mg–3Zn–0.3Ca–0.4La (wt%) alloy was established, which implied that incomplete dynamic recrystallization occurred for the Mg–Zn–Ca–La alloy in the present work. Microstructure analysis indicated that deformation parameters played a critical role on the microstructure optimization. The dynamically recrystallized (DRXed) region fraction and the DRXed grain size were increased with the increase of deformation temperature and decrease of deformation rates.

The microstructure of an Mg–Zn–Ca extrusion was investigated by transmission electron microscopy, and the interaction between dynamic precipitation and dynamic recrystallization was analyzed. The results showed that dynamic precipitation significantly affected the microstructure of the as-extruded Mg–Zn–Ca alloy. The pinning effects of precipitates on dislocations effectively prohibited dynamic recrystallization processes, while the grain boundary precipitate Ca2Mg6Zn3, inhibited the growth of dynamically recrystallized grains. Consequently, a bimodal microstructure with fine dynamically recrystallized (DRXed) grains and elongated deformed regions was obtained for the Mg–Zn–Ca extrusion. High-resolution transmission electron microscopy indicated that the intragranular precipitate MgZn2 had a crystal orientation relationship with α-Mg in the form of (0002)Mg//(10–13)MgZn2 and [1–100]Mg//[1–210]MgZn2, which was beneficial for strength improvement.

The present study compared the effects of minor addition of Ca and Ce on microstructure and mechanical properties of Mg-3Zn (wt. %) alloys. Results showed that Ce or Ca refined the microstructure and affected the texture obviously. Ca weakened the intensity of basal texture, whilst a non-basal texture was obtained for Ce containing alloy. Such texture modification are related to the solid solution of solution atoms and gave rise to the improvement of ductility. Compared with Ca, Ce was more effective to modify the texture and improve the plasticity.

In order to improve the tribological performance, a series of graphite-like carbon (GLC) films with different graphite target power densities were prepared by magnetron sputtering. The valence bond and microstructure of films were characterized by AFM, TEM, XPS and Raman spectra. The variation of mechanical and tribological properties with graphite target power density was analyzed. The results showed that with the increase of graphite target power density, the deposition rate and the ratio of sp2 bond increased obviously. The hardness firstly increased and then decreased with the increase of graphite target power density, whilst the friction coefficient and the specific wear rate increased slightly after a decrease with the increasing graphite target power density. The friction coefficient and the specific wear rate were the lowest when the graphite target power density was 23.3 W/cm2.

The single crystal of Al2O3/Y3Al5O12/ZrO2 ternary eutectic was prepared by an optical floating zone furnace. The crystallography and interfacial structure of the directionally solidified ternary eutectic were investigated by means of electron backscattered diffraction and transmission electron microscopy. We found that the preferred crystallographic orientation of the Al2O3/Y3Al5O12/ZrO2 eutectic crystal was { 11 2 ¯ 0 }〈 1 1 ¯ 00 〉Al2O3 ||{001}〈001〉Y3Al5O12 ||{001}〈001〉ZrO2. Most of the tiny ZrO2 locates dispersively between Al2O3 and Y3Al5O12. It can be concluded that interfacial energy between Al2O3-Y3Al5O12-ZrO2 played an important role in deciding the preferred crystallographic orientations of the Al2O3/Y3Al5O12/ZrO2 eutectic and the precipitation behavior of the ZrO2 phase.

An investigation on the corrosion protection and electrical conductivity films on metal bipolar plates can be achieved through magnetron sputtering. This work characterized the microstructures of TiN–Ag nanocomposite deposited at different temperatures with thermal stabilization. All the TiN–Ag films show adequate electrical conductivity with the interfacial contact resistance (ICR) of 4.81, 4.78, 4.52, 4.18 mΩ cm2 at the deposition temperature of 200 °C–350 °C on SS substrates, respectively, and corrosion resistance with the corrosion current density (Icorr) of 0.678, 0.526, 0.293, 0.596 μA cm−2. Additionally, the TiN–Ag film possesses the hydrophobic property with a static water contact angle of 106.7° at 350 °C. In summary, the TiN–Ag film on SS at 350 °C shows the potential application as metal bipolar plates of PEMFCs.

In this work, we prepared N-doped reduced graphene oxide/Co0.85Se (N-rGO/CS) microflowers through a two-step method. Since introducing N-doped rGO, the fabricated N-rGO/CS electrode with a high mass loading (~8.83 mg/cm2) exhibits high areal specific capacity of 0.522 mAh/cm2 (4.24 F/cm2) at 1 mA/cm2, and a long-term cycling stability (85.8% of capacity retention after 6000 charge-discharge cycles). This is mainly because N-doped rGO can increase specific area and electrical conductivity, enhance the electrochemical activity and effectively facilitate the electron/ion transport between the electrode and electrolyte. Besides, the quasi-solid-state hybrid supercapacitors (HSCs) assembled by the N-rGO/CS delivers a high volumetric specific capacity of 5.82 mAh/cm3 at 1 mA/cm2, excellent energy density of 4.65 mWh/cm3 under 10.5 mW/cm3 and eminement cycle stability (87.6% retention over 6000 cycles at 10 mA/cm2).