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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.

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 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.

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.

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.

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.

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 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).

The present research investigated ageing treatment on dynamic recrystallization and texture in Mg-Zn alloy by optical microscopy (OM), transmission electron microscopy (TEM) and electron backscattered diffraction (EBSD). Mg-6 wt.%Zn alloys were firstly solution and ageing treatment, and then the solutionized and peak-aged alloys were compressed at elevated temperature. The microstructure and texture were systematically investigated. Optical microstructure showed that ageing treatment prohibited dynamic recrystallization during deformation, which was because the precipitates inhibited dislocation movement and restricted the formation of deformation bands. The DRXed region and deformed region both contained typical basal texture with basal planes oriented perpendicular compression direction, but the recrystallized region showed a much weaker texture. The peak-aged alloy containing rod-shaped precipitates exhibited stronger texture intensity after dynamic recyrallization compared with the as-solutionized alloy, which was because the precipitates in the peak-aged alloy inhibited the lattice rotation of the newly formed DRXed grains or affected the microstructural evolution.

Molybdenum nitride (MoN x ) coatings with different nitrogen content were deposited by reactively sputtering molybdenum metal target with various N 2 flow rate. The structure of the coatings were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectrometry (XPS). The mechanical and tribological properties of the coating were evaluated by nano-indentation and ball-on-disc wear tests, respectively. The structural analysis showed that these coatings changed from bcc α-Mo phase to fcc γ-Mo 2 N phase, and then to fcc B1-MoN with the increase in N 2 flow rate. As the phase structure changed from α-Mo to γ-Mo 2 N, the MoN x coatings exhibit finer grain sizes and denser crystal structure, which have dramatic contribution on hardness enhancement. The γ-Mo 2 N coating exhibits the highest hardness with the value of 32.5 GPa. As phase structure further changed to B1-MoN coating, a slight decline of hardness can be observed. The γ-Mo 2 N structured coatings exhibited lower COF than that of mainly Mo structured MoN x coating or B1-MoN coating.

Nanocrystalline Ti films were deposited by continuous dc magnetron sputtering (dcMS), pulsed dc magnetron sputtering (PMS) and cathodic arc evaporation (CAE) separately. Their structures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Mechanical and corrosion properties were studied via nanoindentation, microscratch test and electrochemical measurement. It was found that the dcMS Ti film exhibited a loose porous columnar structure with low film-substrate adhesion. Abundant macroparticles could be observed on the surface of CAE Ti film and it had a low film-substrate adhesion. On the other hand, the ion flux and ion energy of deposited particles in the PMS plasma were enhanced by increasing the average target power and decreasing the area of the sputter track as compared to those of the dcMS plasma. The high-power-density PMS Ti film exhibited a dense microstructure, fine grain size and smooth surface, with jointly enhanced corrosion resistance (corrosion current density of 0.04 μA · cm− 2) and film-substrate adhesion (critical load of 50 N).

Nanoaprticles(Nps)-Ag/TiO 2 multilayer films with different working pressures of Ag and inserted SiO 2 shell layers between Ag and TiO 2 were prepared by alternate magnetron sputtering. The formation of Ag nanoparticles embedded in TiO 2 matrix was confirmed by the XRD and TEM results. The optical absorption peaks assigned to the surface plasmon resonance (SPR) of Ag nanoparticles were observed in the wavelength range of 550–750 nm. With increasing working pressure of Ag, the SPR peaks show blue-shift due to the decreasing Ag Nps size and increasing spacing between them. Compared with the pure TiO 2 film, the Nps-Ag/TiO 2 and Nps-Ag/SiO 2 /TiO 2 film show significantly enhanced Raman scattering due to the strong local field induced by the SPR of Ag nanoparticles, and the enhanced photocatalytic activity of Nps-Ag/TiO 2 film is related with the improved charge separation by the embedded Ag nanoparticles.

The Mg–6 wt% Zn alloys microalloyed with different amounts of La were cast and extruded. The second phase in the as-cast Mg–Zn alloy is Mg4Zn7, which was replaced by Mg–Zn–La intermetallics with orthorhombic structure after La addition. Microalloying with La refined the grain size of dynamic recrystallization slightly, which was due to La solute atom in α-Mg alloy. Addition of La weakened the texture and gave rise to the formation of non-basal texture component, attributing to the existence of La in the form of solute atoms in matrix. The ductility was enhanced significantly by adding La to Mg–6 wt% Zn alloy, while the strength was reduced. Such phenomenon was related to the weakening texture of the La containing alloys. The Mg–6Zn–0.2La (wt%) alloy exhibited a superior ductility with the elongation-to-fracture up to 35%. However, with further increasing of La content to 1 wt%, the strength of the as-extruded Mg–Zn–La alloys was not improved but the ductility was reduced, suggesting that small addition of La is preferred for the improvement of mechanical properties.

The effects of partitioning treatment on microstructure and mechanical properties of austempered ductile iron (ADI) were investigated in the present study. The microstructure of the ADI sample was composed of spheroidal graphite, nano-scale α phase, and high-carbon γ phase. During the partitioning process, the carbon atoms transported from α phase to γ phase, which resulted in the coarsening of α phase and the increase of carbon concentration in γ phase. The carbon concentration in γ phase was increased from 1.6 wt% for ADI to about 2.1 wt% for the sample after partitioning treatment. These microstructure variations resulted in an increase in plasticity by about 50% without sacrificing strength.

Optimizing the electrolytic composition is of practical interest to evaluate the flow battery's weatherability. In this work, the electrolytic composition is optimized for different temperature ranges according to the physicochemical characteristics of electrolyte from −30 °C to 50 °C. The solubility curves of lead methanesulfonate are obtained in methanesulfonic acid, and an equation is proposed among lead methanesulfonate's content, methanesulfonic acid's content and temperature. The conductivity and dynamic viscosity of electrolytes with different compositions can be enhanced by increasing temperature. The voltage efficiency of cell is improved with increasing temperature, but the coulombic efficiency has the maximum value around 30 °C. The high energy efficiency can be achieved by increasing the concentration of H+ below 0 °C or increasing the concentration of Pb2+ above 30 °C. The electrolytic composition of 1.5 M Pb2+ and 1.0 M H+ is suitable for the temperature range of −20 °C − 50 °C. It is also found that the concentration of H+ is demanded at least 0.17 mol/L for charging the battery.

The thin-film electrode for supercapacitors has broad prospects for providing high energy storage capacity. However, the microstructure of dense film resulting in poor ion access limits its capacitance still far below the theoretical value. Here, CrN thin film electrodes with good cycle performance can be prepared by tuning the porosity of the film at the nanoscale level. The atomic diffusion process and atomic peening effect that occur during the sputtering process of chromium nitride are the pivotal parameters for generating porosity and high specific surface area. During the controlled sputtering process, an increase in the nitrogen flow rate causes an increase in the porosity in each column (intracolumnar porosity), while an increase in temperature controlling the gap between two columns (intercolumnar porosity). When the nitrogen flow rate is 10 sccm and the deposition temperature is 250 °C the CrN film has the areal capacitance of 41.7 mF cm−2, 10 mV s−1 at the thickness of 950 nm. In addition, the CrN film has good electrochemical cycling stability, the capacity retention rate is still as high as 93.2% after 20,000 cycles. Therefore, the CrN film electrode has a promising application prospects in energy storage systems such as supercapacitors.

Highly conductive silver nanoparticles doped in graphite-like coating (GLC) can significantly optimize the conductivity of the film, while Ag and carbon could not form stable compounds, leading to rapidly escaping of Ag atoms to the surface of coatings. In this work, Ag doped GLC films deposited by magnetron sputtering technique at different temperatures (200–350 °C) are investigated. The results show that silver aggregates into nanowires along the carbon cluster interface in GLC at the deposition temperature of 350 °C and films show excellent hydrophobic property with the contact angle as high as 128.68°, interfacial contact resistance as low as 3.76 mΩ·cm2, and corrosion resistance improving remarkably, indicating that thermal stabilization under negative pressure can optimize film performance to make it as an excellent candidate for metal bipolar plates.

In lead methanesulfonate flow battery, with the charge/discharge cycling, some PbO2 drops into the electrolyte, decreasing the efficiency of the battery and limiting its service life. In this work, an aqueous solution of soluble lead trifluoromethylsulfonate is firstly proposed as a supporting electrolyte for the lead soluble flow battery. Its efficiency and the cycling stability can be improved. Compared with the Pb(CH3SO3)2/CH3SO3H electrolyte, the kinetics and reversibility of PbO2/Pb2+ are improved in the Pb(CF3SO3)2/CF3SO3H electrolyte. The charge voltage in the Pb(CF3SO3)2/CF3SO3H electrolyte is lower than that in the Pb(CH3SO3)2/CH3SO3H electrolyte at the same current density in the range of 10 - 60 mA cm−2. Moreover, the PbO2 layer deposited in the Pb(CF3SO3)2/CF3SO3H electrolyte is smooth and compact, no any PbO2 particles are observed to drop off from the positive electrode over tens of cycles. Pb particles are smaller than those deposited in the Pb(CH3SO3)2/CH3SO3H electrolyte. More impressively, the high columbic efficiency is dropped down to 80% after 244 cycles at a current density of 40 mA cm−2 by employing the Pb(CF3SO3)2/CF3SO3H electrolyte.

The phase constituents and mechanical properties of Cr/CrAlN and Cr/CrN/Cr/CrAlN coatings which prepared by Arc Ion Plating were investigated in this work. The stress variation of the coating process was investigated by the finite element method and the failure mechanism of the coatings was analyzed. The results suggested that the, Cr/CrN/Cr/CrAlN coating have fewer surface micro-particles, higher adhesion strength (86.7 ± 2.1 N), and lower residual stress (−1.665 ± 0.042 GPa) compared with Cr/CrAlN coating. In addition, the erosion resistance performance of the multilayer coatings is obviously higher than that of the uncoated specimen. According to crack growth and stress analysis, it is found that Cr/CrN/Cr/CrAlN coating has better longitudinal and transverse stress dissipation ability. During the impact of solid particles, high tensile stress is the main reason for the formation and propagation of brittle cracks in the coating. In addition, according to the plastic-brittle (DBT) transition of the Cr layer, it is inferred that the fracture failure mechanism of the coating is a joint mechanism of brittleness and toughness.

The tribological behavior of austempered ductile iron (ADI) obtained at different austempering temperatures is investigated. The microstructure of ADI is consisted of spheroidal graphite, retained austenite and acicular ferrite. The volume fraction of retained austenite and the thickness of acicular ferrite increase with increasing austempering temperature, which results in strength reduction but plasticity increasement. With the increase of austempering temperature, the friction coefficient changes little under low load (5 N) but decreases under high loads (10 N and 15 N), whilst the wear rate increases under low load (5 N) but changes little under high loads (10 N and 15 N). This wear behavior is attributed to the combined effects of hardness and friction coefficient. Additionally, adhesive and abrasive wear are main failure mechanisms for ADI under dry sliding wear condition.

In this work, different soluble lead electrolytes, lead methanesulfonate, lead trifluoromethylsulfonate and lead perchlorate are selected to investigate the characteristics of anodic electrodeposited materials. The charge current is large in Pb(CF3SO3)2/CF3SO3H electrolyte, followed by those in Pb(ClO4)2/HClO4 and Pb(CH3SO3)2/CH3SO3H solutions at the same positive electrode potential of 1.7 V vs. SCE. Physiochemical properties of PbO2, such as the particle size and its distribution, α-phase and β-phase, and the non-stoichiometry of PbO2 are investigated using SEM, XRD and XPS. PbO2 particles have a ball shape, which are electrodeposited in different electrolytes. Their sizes are 1.97 ± 0.84, 1.13 ± 0.35 and 1.78 ± 0.21 μm in Pb(CH3SO3)2/CH3SO3H, Pb(CF3SO3)2/CF3SO3H and Pb(ClO4)2/HClO4 electrolytes respectively. α-PbO2 has a larger grain size than β-PbO2 in those three electrolytes. PbOx (x = 1.72) with the highest oxygen content is obtained in Pb(CF3SO3)2/CF3SO3H electrolyte. Compared with other solutions, the reversibility of PbOx/Pb2+ exhibits the best in Pb(CF3SO3)2/CF3SO3H electrolyte, and the coulombic efficiency of 96.0 ± 0.4% is achieved.

The temperature adaptability of the lead methanesulfonate flow battery is evaluated from 253 K to 323 K. The energy efficiency reaches the maximum value of 85.7% at 313 K. The overpotentials of positive and negative couples decrease with increasing temperature, especially for the PbO2/Pb2+ couple. The high temperature can not only promote the diffusivity of ions, but also reduce the charge transfer resistance Rct and electrolyte resistance RL, which lower the electrode overpotential to improve the voltage efficiency. The coulombic efficiency of flow cell is mainly attributed to the reversibility of PbO2/Pb2+ half reaction, and the maximum value of 97.6% is achieved at 303 K. Many more defects and clusters appear on Pb and PbO2 deposited layers at low temperature. The particle size of PbO2 increases with increasing temperature, and the pure β-PbO2 can be obtained at 323 K. With the temperature increasing, the grain size of Pb is increased, and especially PbO2’s is apparently enlarged.

Ca single or Ca–Ce double microalloying Mg–Zn alloy was cast and extruded in the present study. The combined addition of Ca and Ce improved the mechanical properties of Mg–6Zn alloy after extrusion obviously. Microstructure analysis reveals that Ca or Ca–Ce addition refined the dynamic recrystallized (DRXed) microstructure, promoted dynamic precipitation and modified the texture. The fine precipitates in the as-extruded Mg–Zn–Ca–Ce alloy pinned dislocation movement and inhibited dynamic recrystallization, resulting in a bimodal microstructure with fine-grained DRXed region and elongated deformed region. The recrystallization texture was weakened with Ca or Ca–Ce addition, which was mainly attributed to the particle stimulated nucleation (PSN) and shear bands nucleation (SBN). Compared with single Ca microalloying, Ca–Ce double microalloying was more effective to improve the mechanical properties of Mg–6Zn alloy. The as-extruded Mg–6Zn–0.7Ca–0.2Ce (mass%) alloy exhibited a good combination of strength and ductility with the yield strength of 287 MPa and elongation-to-fracture of 16.9%, which was related to the fine DRXed grains with weaker texture, high density precipitates, and the deformed region with strong basal texture.

CrTiAlN and CrTiAlMoN nano-multilayer coatings were deposited by closed field unbalanced magnetron sputtering. TiMoN and CrTiMoN nano-multilayer coatings with same Mo 2 N layer thickness were also prepared for comparison. The structure of these coatings is investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The mechanical and tribological properties were characterized and compared by nano-indentation and ball-on-disc test. It was found that these coatings were structured by fcc metal nitride phases (including CrN, TiN, AlN and Mo 2 N) and the preferred orientation changed from (1 1 1) to (2 0 0) with the increase of Mo content. The TEM results showed that the coatings exhibited typical columnar structure and nano-multilayer structure with modulation periods ranged from 3.2 nm to 7.6 nm. Among these coatings, CrTiAlMoN coatings presented the highest hardness, lowest coefficient of friction (COF) and wear rate. The hardness of these nano-multilayer coatings were determined by layer interfaces: TiN/Mo 2 N and AlN/Mo 2 N layer interface showed benefit on hardness enhancement while CrN/Mo 2 N layer interface led to a great hardness decrement. In comparison with the other as-deposited coatings, the low COF of CrTiAlMoN coatings was not only affected by Mo addition but also related to its oxidation behaviors.

Nanocrystalline titanium films were deposited at ultra-high current density by a direct-current closed-field unbalanced magnetron sputtering technique. The structures and properties of the films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and nanoindentation microscratch. The Ti film deposited at target current density of 0.267 A/cm 2 exhibited a polycrystalline microstructure with average grain size of 16 nm, fine columnar structure with no obvious voids and smooth surface, better film thickness uniformity in different parts, and excellent film–substrate adhesion. These results showed that the excellent film structure and performances were primarily achieved by using high ionization rate and energy of target atoms. As current density exceeded 0.175 A/cm 2 , ionization rate and energy of target atoms were greatly improved owing to the thermally-enhanced spontaneous emission of atoms and electrons from the target by Ar + bombardment and Joule heating.

The Mo 2 N/AlN multilayer coatings with AlN layer thickness in the range of 0.5 nm to 3.7 nm were deposited by dc magnetron sputtering. The Mo 2 N/AlN multilayer coatings exhibited columnar growth structure. As the AlN layers’ thickness exceeds 1.2 nm, AlN layers changed from fcc structure to amorphous structure, which breaks off the crystallization integrity of multilayer coatings. The coatings oxidized at 400 °C, 550 °C, 700 °C in air for 1 h were investigated by X-ray diffractions (XRD), X-ray photoelectron spectroscopy (XPS) and Scanning electron microscopy (SEM). It was found that with the increase of AlN layer thickness, the oxidation resistance of Mo 2 N/AlN multilayer coatings was improved by reducing the density of columnar grain boundaries and forming dense Al 2 O 3 oxide layer on the surface. The addition of AlN to Mo 2 N coatings also leads to the lower coefficient of friction (0.36–0.42) of Mo 2 N/AlN multilayer coatings than that (0.62) of Mo 2 N coatings.

in the paper, for the first time, the synthesis of aluminum nitrides microparticles with a hierarchically meso-macroporus structure were reported by an aluminum-magnesium alloy nitridization routine. The hierarchically meso-macroporous aluminum nitrogen with a specific surface area of 97.7 m 2 /g and a specific mesopore volume of 0.10 cm 3 /g was prepared by nitriding an aluminum-magnesium alloy with diameters between 75 µm and 150 µm at the temperature 500 °C for 8 h firstly and then 800 °C for 6 h.