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Since China reform and opening, the real estate industry has gradually developed into a pillar industry of China's economy. In recent years, the Chinese government introduced a tightening policy to limit the expansion of the real estate bubble, but also put pressure on the real estate sector, financing problems are imminent. This article investigates the theme of China's real estate enterprises different financing methods. This study selects two Chinese listed real estate companies as the case, analyzes the relevant data in the financial reports published by the two companies contemporarily. It compares the advantages and disadvantages of different financing methods. According to the analysis, companies that pay attention to internal financing, develop diversified financing channels, have strong corporate strength, and have financing methods that respond to government policies are more capable of financing. These results shed light on helping the choice of financing methods of real estate companies in China and further exploration of financing modes.

A series of three-dimensional ordered macroporous (3DOM) W–TiO2 catalysts have been prepared through a facile colloidal crystal template method. The prepared materials characterized in detail exhibited enhanced catalytic activity in aerobic oxidative desulfurization process. The experimental results indicated that the as-prepared materials possessed excellent 3DOM structure, which is beneficial for the catalytic activity. The sample 3DOM W–TiO2-20 exhibited the highest activity in ODS process, and the sulfur removal can reach 98% in 6 h. Furthermore, the oxidative product was also analyzed in the reaction process.

The change in material dimensional will lead to the decline of instrument accuracy and reliability. In this paper, the characterization and analysis of the lattice constant, precipitates, and dislocation density of the material by X-ray diffraction (XRD) and transmission electron microscopy (TEM) reveals the reason why the relative dimensional change in the rolled 2024Al is one order of magnitude lower than that of the as-cast 2024Al during isothermal aging. Compared with as-cast 2024Al, the dislocation density of rolled 2024Al is higher, the lattice constant decreases less before and after aging, and the precipitates have orientation and more content, resulting in the dimensional change in rolled 2024Al being smaller than that of as-cast 2024Al. In addition, two main reasons for decreasing the dimensional change in rolled 2024Al are discussed: the decrease in lattice constant, the formation and growth of the S phase before and after aging.

Composite material uses ceramic reinforcement to add to the metal matrix to obtain higher material properties. Structural design is an important direction of composite research. The reinforcement distribution of the core-shell structure has the unique advantages of strong continuity and uniform stress distribution. In this paper, a method of preparing boron carbide (B4C)-coated titanium (Ti) powder particles by ball milling and preparing core-shell B4C-reinforced Ti matrix composites by Spark Plasma Sintering was proposed. It can be seen that B4C coated on the surface of the spherical Ti powder to form a shell structure, and B4C had a certain continuity. Through X-ray diffraction characterization, it was found that B4C reacted with Ti to form layered phases of titanium boride (TiB) and titanium carbide (TiC). The compressive strength of the composite reached 1529.1 MPa, while maintaining a compressive strain rate of 5%. At the same time, conductivity and thermal conductivity were also characterized. The preparation process of the core-shell structure composites proposed in this paper has high feasibility and universality, and it is expected to be applied to other ceramic reinforcements. This result provides a reference for the design, preparation and performance research of core-shell composite materials.

In this paper, two kinds of Be/2024Al composites were prepared by the pressure infiltration method using two different beryllium powders as reinforcements and 2024Al as a matrix. The effect of interfacial strength on the mechanical behavior of Be/2024Al composites was studied. Firstly, the microstructure and mechanical properties of the two composites were characterized, and then the finite element analysis (FEA) simulation was used to further illustrate the influence of interfacial strength on the mechanical properties of the two Be/2024Al composites. The mechanical tensile test results show that the tensile strength and elongation of the beryllium/2024Al composite prepared by the blocky impact grinding beryllium powder (blocky-Be/2024Al composite) are 405 MPa and 1.58%, respectively, which is superior to that of the beryllium/2024Al composite prepared by the spherical atomization beryllium powder (spherical-Be/2024Al composite), as its strength and elongation are 331 MPa and 0.38%, respectively. Meanwhile, the fracture of the former shows brittle fracture of beryllium particles and ductile fracture of aluminum, while the latter shows interface debonding. Further FEA simulation illustrates that the interfacial strength of the blocky-Be/2024Al composite is 600 MPa, which is higher than that of the spherical-Be/2024Al composite (330 MPa). Therefore, it can be concluded that the better mechanical properties of the blocky-Be/2024Al composite contribute to its stronger beryllium/aluminum interfacial strength, and the better interfacial strength might be due to the rough surface and microcrack morphology of blocky beryllium particles. These research results provide effective experimental and simulation support for the selection of beryllium powder and the design and preparation of high-performance beryllium/aluminum composites.

The microstructure evolution of the B4C/Al interface is very complicated, which has not been fully understood yet. The main products reported in the literature works are Al-B phases (AlB2 and AlB12) or Al-B-C phases (Al3BC and AlB12C2). However, the most common Al4C3 phase in Al-C systems was rarely reported, which could not be explained by reaction thermodynamics. In the present work, the interfacial bonding evolution between B4C and Al was calculated by the thermodynamic analysis and first-principle method. According to the thermodynamic analysis, Al-B phases (AlB2 or AlB12) and Al-C phase (Al4C3) would be formed simultaneously, which was inconsistent with the experimental result. Furthermore, the first-principle calculation indicated the formation of strong chemical bond at the B4C/Al interface. The population bonding analysis revealed that the interface bonding was B-Al bond. Due to the pull of chemical bond forces, the B elements tended to be enriched at the interface, while the C element tended to be far away from the interface. Eventually, the interface-enriched B element preferentially reacted with the Al matrix to form AlB2 and AlB12 and further evolved to be Al-B-C phases (Al3BC and AlB12C2). However, the C element could not preferentially participate in the reaction.

Background and ObjectivesWhile studies have researched ageism in public policy, few investigated the impact of aging policy on ageism—typically, an unintended consequence. Ageism is linked to $63 billion in health care costs, so its antecedents are of interest. We test the association between Aging Policy Agenda Setting and Societal Age Stereotypes and hypothesize a mediating pathway via Medicalization of Aging, moderated by demographics.Research Design and MethodsScholars identified Singapore’s Pioneer Generation Policy (PGP) as one of the largest policy implementations in recent years, where the agenda was set by the Prime Minister at an equivalent State of the Union address in 2013, and US$7 billion allocated to fund outpatient health care costs for aged 65 years or older. More than 400,000 older adults received a PGP card and home visits by trained volunteers who co-devised a personalized utilization plan. We leveraged a 10-billion-word data set with more than 30 million newspaper and magazine articles to dynamically track Societal Age Stereotype scores over 8 years from pre- to postpolicy implementation.ResultsSocietal Age Stereotypes followed a quadratic trend: Prior to the Aging Policy Agenda Setting from 2010 to 2014, stereotypes were trending positive; after 2014, it trended downward to become more negative. Medicalization of Aging mediated the relationship between Aging Policy Agenda Setting and Societal Age Stereotypes. Furthermore, Old-age Support Ratio moderated the mediational model, suggesting that the impact of policy on medicalization is stronger when a society is more aged.Discussion and ImplicationsWe provided a framework for policymakers to ameliorate the unintended consequences of aging policies on societal ageism—if unaddressed, it will exert an insidious toll on older adults, even if initial policies are well-intentioned.

The study aimed to explore the effect of circ_0008003 on the progression of non-small-cell lung cancer (NSCLC) and its underlying regulation mechanism.Expression of hsa_circ_0008003, miRNA (miR)-548I and karyopherin subunit α 4 (KPNA4) was examined by quantitative real-time polymerase chain reaction. Cell viability and proliferation ability were detected by cell counting kit-8 assay and 5-ethynyl-2'-deoxyuridine assay, respectively. Flow cytometry was performed to monitor cell apoptosis. Western blot assay was used to evaluate the protein levels of KPNA4, Bax, and Bcl-2. Cell migration and invasion were assessed by transwell assays. The targeted relationship between miR-548I and hsa_circ_0008003 or KPNA4 was confirmed by dual-luciferase reporter and RNA immunoprecipitation assays. Furthermore, the role of hsa_circ_0008003 in vivo was investigated by xenograft assay.Circ_0008003 expression was increased in NSCLC tissues and cell lines. Circ_0008003 knockdown reduced cell viability, migration, invasion, angiogenesis, and caused apoptosis in NSCLC cells. Moreover, miR-548I was targeted by circ_0008003, and miR-548I knockdown reversed the influence of circ_0008003 silence on NSCLC progression. KPNA4 was targeted by miR-548I, and miR-548I overexpression suppressed cell viability, migration, invasion, angiogenesis, and promoted cell apoptosis via decreasing KPNA4. In addition, circ_0008003 regulated KPNA4 expression via miR-548I. Circ_0008003 knockdown decreased NSCLC cell growth in the xenograft model.Circular RNA hsa_circ_0008003 promoted progression in NSCLC by sponging miR-548I and regulating KPNA4 expression, hinting that circ_0008003 participates in NSCLC pathogenesis.

The mechanical properties of (Ti, Nb)B/Ti

In the present study, the effects of SiC nanowires (SiCnws) with diameters of 100 nm, 250 nm and 450 nm on the microstructure and mechanical behavior of 20 vol.% SiCnws/6061Al composites prepared by pressure infiltration were studied. It was found that the interface between SiCnws and Al matrix was well bonded, and no interface product was found. The thicker SiCnws are beneficial to improve the density. In addition, the bamboo-like and bone-like morphologies of SiCnws produce a strong interlocking effect between SiCnws and Al, which helps to improve the strength and plasticity of the material. The tensile strength of the composite prepared by SiCnws with a diameter of 450 nm reached 544 MPa. With a decrease in the diameter of SiCnws, the strengthening effect of SiCnws increases. The yield strength of SiCnws/6061Al composites prepared by 100 nm is 13.4% and 28.5% higher than that of 250 nm and 450 nm, respectively. This shows that, in nano-reinforced composites, the small-size reinforcement has an excellent improvement effect on the properties of the composites. This result has a guiding effect on the subsequent composite structure design.

The scaffold layer plays an important role in transporting electrons and preventing carrier recombination in mesoporous perovskite solar cells (PSCs), so the engineering of the interface between the scaffold layer and the light absorption layer has attracted widespread concern. In this work, vertically grown TiO2 nanorods (NRs) as scaffold layers are fabricated and further treated with TiCl4 aqueous solution. It can be found that a thin brookite TiO2 nanoparticle (NP) layer is formed by the chemical bath deposition (CBD) method on the surface of every rutile NR with a low annealing temperature (150 °C), which is beneficial for the infiltration and growth of perovskite. The PSC based on the TiO2 NR/brookite NP structure shows the best power conversion of 15.2%, which is 56.37% higher than that of the PSC based on bare NRs (9.72%). This complex structure presents an improved pore filling fraction and better carrier transport capability with less trap-assisted carrier recombination. In addition, low-annealing-temperature-formed brookite NPs possess a more suitable edge potential for electrons to transport from the perovskite layer to the electron collection layer when compared with high-annealing-temperature-formed anatase NPs. The brookite phase TiO2 fabricated at a low temperature presents great potential for flexible PSCs.

Circular RNAs (circRNAs) are key modulators in carcinogenesis and radioresistance in multiple kinds of human cancers.To explore the role of circ_0010235 in non-small cell lung cancer (NSCLC).Cell culture study and animal study.The detection of circ_0010235, microRNA-588 (miR-588), and homeobox protein A10 (HOXA10) was implemented via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). CCK-8, EdU, flow cytometry, transwell, and wound healing assays. These strategies were applied to evaluate cell functions. The western blot technique was employed for protein examination. The colony formation assay was used to determine cell survival after radiation treatment. In vivo research was performed by tumor xenograft assay. The binding analysis was also carried out through dual-luciferase reporter and RNA immunoprecipitation studies.Circ_0010235 had an enhanced expression in NSCLC. Circ_0010235 deficiency inhibited cell proliferation, invasiveness, and migratory ability but promoted apoptosis and radiosensitivity. Downregulation of circ_0010235 decelerated tumor growth and promoted radiation sensitivity in vivo. Circ_0010235 was controlled biologically in NSCLC cells by combining with miR-588 and targeting miR-588. HOXA10 acted as a target of miR-588. MiR-588 upregulation inhibited NSCLC cell malignant phenotypes and elevated radiosensitivity via downregulating HOXA10. Circ_0010235 could regulate the level of HOXA10 by sponging miR-588.Circ_0010235 contributed to the malignant progression of NSCLC, but suppressed the radiation sensitivity via targeting miR- 588 to induce HOXA10 upregulation.

Despite that several strategies have been demonstrated to be effective for improving the catalytic hydrogen evolution activity of bulky g-C3N4, the large-scale hydrogen production over g–C3N4–based photocatalysts still confronts a big challenge. Here, a two-step calcination method is presented in constructing metal oxide/two-dimensional g-C3N4, i.e., Ta2O5/2D g-C3N4 photocatalyst. Thanks to the superiority of the synthetic method, nanostructure engineering forming 2D structure, and surface assembly with another semiconductor, can be realized simultaneously, in which ultrathin structure of 2D g-C3N4 and strong interfacial coupling between two components are two important characteristics. As a result, the structure engineered Ta2O5/2D g-C3N4 induces high photocatalytic hydrogen evolution half reaction rate of ~19,000 μmol g−1 h−1 under visible light irradiation (λ > 400 nm), and an external quantum efficiency (EQE) of 25.18% and 12.48% at 405 nm and 420 nm. The high photocatalytic performance strongly demonstrates the advance of the synchronous engineering of nanostructure and construction of heterostructure with tight interface, both of which are beneficial for the fast charge separation and transfer.

In this study, titania/silica nanocomposite and mesoporous TiO2 (m-TiO2) photocatalysts are developed by KIT-6 template via a sol-gel approach. The synthesized photocatalysts are characterized by XRD, EDX, SEM, Raman, PL, and UV–vis DRS analysis techniques. The as-synthesized series revealed a high surface area, smaller size, a greater number of accessible active sites, and enhanced light-harvesting capability. The m-TiO2 photocatalysts’ charge recombination capability was curiously inferior to the rest of as-synthesized TiO2/KIT-6 nanocomposite materials. The band-gap of as-synthesized materials were suitable for their activity in UV light irradiations. It was pragmatic that the photocatalytic degradation efficiency of m-TiO2 photocatalysts was superior as compared to that of commercial TiO2 photocatalyst under UV light irradiations, owing to the synergistic outcome of the anatase phase and a greater number of accessible active-sites availability as a result of high surface area. Moreover, the m-TiO2 was critically evaluated by investigating various parameters affecting the photocatalytic degradation reaction of MB including the effect of irradiation time, pH, catalyst dosage, and dye concentration. The m-TiO2, 45wt% composite material and commercial-TiO2 exhibited 99.27, 91.20, and 84.67% degradation of methyl blue in 50 min, respectively. Finally, the m-TiO2 exhibited excellent recyclability with negligible loss of activity performance.

This study aimed at the synthesis of heterogeneous acid catalysts by incorporating 12 tungstophosphoric acid (HPW) over mesoporous silica support KIT-6 via impregnation and sol-gel methods to improve the catalytic efficiency of the esterification reaction. The catalytic activity of the KIT-6 supported catalysts was investigated for esterification of oleic acid in the presence of MeOH. Synthesized catalysts were analyzed using scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and Fourier transform infrared (FTIR) spectroscopy techniques. Characterization results showed the variation in porosity, roughness, presence of SiO2 and kegging structure after successful deposition of HPW over KIT-6 surface. Additionally, the textural property of synthesized catalysts was compared with highly active HPW and sulfated KIT-6. The ordered structure of mesoporous silica KIT-6 facilitated the dispersion of HPW resulting in better catalytic stability and activity. To evaluate the impact of synthesizing technique on catalytic activity and effectiveness of heterogeneous acid catalysts, loading of HPW over KIT-6 mesoporous silica was controlled between 10 to 30 wt%. Catalysts synthesized by impregnation and sol-gel methods showed the highest catalytic activity with 30-IM and 25-SG, respectively. The enhanced performance was ascribed to the improved textural property and amount of HPW, which led to higher activity, stability and reusability.

Platinum group metals (PGMs) usually exhibit promising aerobic catalytic abilities, providing a green and feasible oxidative desulfurization method. However, often, the PGM nanoparticles (NPs) get leached, and the catalysts are deactivated. In this work, Pt NPs with particle sizes of approximately 4–5 nm were encapsulated effectively and uniformly on the surface of vanadium pentoxide (V2O5) nanosheets (with thicknesses of approximately six atomic layers) through strong metal-support interactions. The synthesized catalysts promote catalytic aerobic oxidation reactions, realizing deep desulfurization (99.1%, l 5 μg g−1) under atmospheric pressure and 110 dC reaction temperature. Remarkable degrees of sulfur removal could be achieved for oils with different initial S-concentrations and substrates. Additionally, the as-prepared catalysts could be recycled for reuse at least seven times.

In recent years, transition-metal oxides (TMOs) have been long employed for aerobic oxidative desulfurization. However, the inherent bottlenecks, such as the low explosion of active sites, limit the application of bulk TMOs catalyst. In this study, V2O5 nanoparticles with oxygen vacancies were prepared in large-scale via facile ball milling strategy with adding oxalic acid as a reducing agent. The as-prepared catalysts exhibit remarkable sulfur removal for oils with different initial S-concentrations and different substrates. Sulfur removal could reach up to 99.7% (< 2 ppm) under the optimized reaction conditions. This work provides a feasible desulfurization strategy for fuel oils.

A new strategy to enhance the photocatalytic properties of graphitic carbon nitride is reported via constructing an effective NiO decorated Ti/TiO2NT/TiO2/g-C3N4 S-scheme heterostructure photocatalyst thin film (Ti/TiO2NT/TiO2/g-C3N4/NiO). This thin film photocatalyst can separate hydrogen gas and oxygen gas into different sides of the Ti substrate. Owing to the synergistic effect of the NiO as co-catalyst and the formation of Step-scheme (S-scheme) heterojunction between g-C3N4 and TiO2, the electrons and holes were successfully separated to their opposing active centers, which is beneficial to inhibiting the recombination of the charge carriers. The gas evolution rate of Ti/TiO2NT/TiO2/g-C3N4/NiO is 7.97 μmol h−1 cm−2 under the irradiation of high-pressure mercury lamp, which was 3 and 1.3 times as high as that of the Ti/TiO2NT/g-C3N4 and Ti/TiO2NT/TiO2/g-C3N4, respectively. Firstly, benefiting from the well-matched band structure, a direct S-scheme Ti/TiO2NT/g-C3N4 heterojunction thin film is constructed easily driven by the built-in electric field across the Ti/TiO2NT/g-C3N4 interface. Furthermore, the introduction of the TiO2 layer on the TiO2NT will broaden light absorption range and increase the heterojunction area, which in turn conduces to effective charge separation. In addition, NiO as a co-catalyst cannot only accelerate the charge separation but also provide plentiful catalytic sites and decompose H2O2 produced by g-C3N4. The thin film photocatalysts can be recycled again, which is different from traditional powdered photocatalysts. This work constructs a NiO decorated Ti/TiO2NT/TiO2/g-C3N4 S-scheme heterostructure photocatalyst thin film, and provides a new insight to promote photocatalytic activity of g-C3N4 under the synergetic impact of S-scheme heterostructure and NiO co-catalyst. A novel NiO decorated Ti/TiO2NT/TiO2/g-C3N4 S-scheme heterostructure photocatalyst thin film was fabricated to enhance photocatalytic activity for water splitting.

In the present work, the properties of graphene-nanoplates/aluminum (GNPs/Al) composites with a heterogeneous matrix design were investigated. The advantage of the heterogeneous matrix was investigated by the finite element method. Then, 0.6 wt.% (GNPs/6061Al)/2024Al (heterogeneous matrix) and 0.6 wt.% GNPs/6061Al composites were prepared by ball milling, pressure infiltration technology, and hot extrusion. The aggregation of GNPs was eliminated and the interlayer slide of GNPs was observed. Mechanical property test results show that the mechanical properties of the heterogeneous matrix composite are better than that of a homogeneous matrix composite, including strength, elastic modulus, and plasticity. It is assumed that the heterogeneous matrix design enhances the non-uniform stress field during the deformation treatment. This improves the dispersion of GNPs, grain refinement, and produces the few-layer graphene (FLG), thus enhancing the strengthening effect of GNPs. Meanwhile, heterogeneous matrix design is thought to introduce more hardening mechanisms to increase the plasticity of materials and improve the intrinsic trade-off of strength and toughness.

Fe-based oxide electrodes for practical applications in supercapacitors (SCs) suffer from low conductivity and poor structural stability. To settle these issues, we report on the design and synthesis of Fe3O4/carbon nanocomposites via firmly anchoring mesoporous Fe3O4 nanospheres onto N-doped carbon nanotubes (N-CNTs) via C–O–Fe bonds. Mesoporous Fe3O4 nanospheres are featured by rich electroactive sites and short ion diffusion pathways. The N-CNTs, on the other hand, serve as the scaffolds, which not only provide conductive networks but also suppress the accumulation between mesoporous Fe3O4 nanospheres as well as alleviate volume changes during charge/discharge cycles. Accordingly, the constructed Fe3O4/N-CNTs nanocomposite electrode demonstrates improved specific capacity values of up to 314 C g−1 at 1 A g−1, with 92% retention of the initial capacity after 5000 cycles at 10 A g−1. In addition, the assembled Fe3O4/N-CNTs//active carbon (AC) asymmetric supercapacitor (ASC) device possesses an energy density of 25.3 Wh kg−1, suggesting that the prepared Fe3O4/N-CNTs nanocomposites are promising electrode materials for use in SCs.

Functionalized ionic liquids (ILs) have been considered as efficient catalysts for oxidative desulfurization (ODS), but the further industrial applications are hampered by the poor separability wit...

Graphene has excellent theoretical properties and a wide range of applications in metal-based composites. However, because of defects on the graphene surface, the actual performance of the material is far below theoretical expectations. In addition, graphene containing defects could easily react with a matrix alloy, such as Al, to generate brittle and hydrolyzed phases that could further reduce the performance of the resulting composite. Therefore, defect repair is an important area of graphene research. The repair methods reported in the present paper include chemical vapor deposition, doping, liquid-phase repair, external energy graphitization, and alloying. Detailed analyses and comparisons of these methods are carried out, and the characterization methods of graphene are introduced. The mechanism, research value, and future out-look of graphene repair are also discussed at length. Graphene defect repair mainly relies on the spontaneous movement of C atoms or heteroatoms to the pore defects under the condition of applied energy. The repair degree and mechanism of graphene repair are also different according to different preparations. The current research on graphene defect repair is still in its infancy, and it is believed that the problem of defect evolution will be explained in more depth in the future.

Hydrodesulfurization is a valuable cornerstone in the modern refineries, aiming to reduce sulfur-containing compounds to produce cleaner end-products, by using heterogeneous metal catalysts at elev...

Small solid rocket motors (SRM) require low density, low ablation nozzle-throat materials. In the present study, Al20Si alloy was infiltrated into the porous graphite matrix to develop Al20Si/graphite composites by pressure infiltration method. The ablation behavior of the as-prepared composite was investigated in a small SRM testing system with an average pressure of 13.3 MPa and 5 wt% Al for 1.4 s. The results show that the linear ablation rate of the Al20Si/graphite throat decreased by 92% compared to that of the C/C composite throat. The increased anti-ablative properties are provided by Al20Si alloy fillers, which reduce the degree of thermochemical ablation of the graphite matrix through heat dissipation, oxygen dissipation, and thermal blockage. Furthermore, the Al4SiC4 generated from Al20Si alloy and graphite fills graphite pores, which contributes to the oxidation resistance of the composite.

In this paper, to improve the hot deformability and corrosion resistance, a nanoamorphous B2O3 layer was designed and fabricated between B4C particles and an Al matrix successfully. The B4C@B2O3/Al composites were prepared by a hot-pressed sintering method. By contrast, the B4C/Al composites were synthesized using the same preparation method. The results show that the existence of an amorphous layer can effectively inhibit the formation of Al3BC, AlB12, and other reaction products at the interface, compared with B4C/Al composites. At the same time, the existence of an amorphous B2O3 layer can reduce the maximum deformation resistance of the composites under the compression conditions of 500 °C and 0.001 s–1, to about 76% lower than that of the B4C/Al composites, and improve the hot deformability significantly. Furthermore, the corrosion current density of B4C@B2O3/Al composites is 82.5% lower than that of the B4C/Al composites. The good corrosion resistance makes B4C@B2O3/Al composites a potential neutron shielding material.

In the present work, 0.6 wt% graphene nanoplatelets reinforced 6061Al (GNPs/6061Al) composite was prepared by pressure infiltration process and hot extruded (HE) at 420 °C∼500 °C in order to investigate the evolution of GNPs in different extrusion temperature, which has not been reported yet. The GNPs agglomeration were eliminated by extrusion and were arranged in an orientation. In the sample extruded at 420 °C, the dispersion effect was not significant and agglomeration of large-sized GNPs was still found. However, the agglomeration of the GNPs was eliminated when extruded at 450 °C, and waved structure, exfoliation and bend of GNPs were observed. While in the sample at 500 °C, interlayer sliding of GNPs and interfacial reaction product Al4C3, due to excessively high extrusion temperature, were detected. The composites extruded at 450 °C showed the highest yield strength and ultimate tensile strength of 389 MPa and 500 MPa, respectively, which increased 16.8% and 40.1% comparing with the unreinforced matrix. The present results indicate that the uniform dispersion of graphene is still one of the main challenges in Graphene/Al composites, while the deformation treatment provides the possibility of further dispersion of graphene.

The interfacial bonding affects the performance of Graphene/Al matrix composites significantly. However, the relationship between interfacial structure and mechanical properties has not been fully understood yet. In the present work, the GNPs/Al composites were prepared by pressure infiltration method, and the interface structure of Graphene-Al2O3–Al and graphene-(Al4C3, Al2OC)–Al was prepared by addition of polydimethylsiloxane (PDMS) as process control agent (PCA). The tensile strength of the GNPs/Al composite material with Al2O3 interfacial bonding was 303 MPa, which was about 30% higher than that with Al4C3 and Al2OC interface. Moreover, calculated by first-principle, it has been found that the interfacial shear strength of the graphene-Al2O3–Al interface (378 MPa) was much higher than that of graphene-Al (37 MPa), graphene-Al4C3 (83 MPa) and graphene-Al2OC (66 MPa), which leads to the improved mechanical properties.

This study was conducted to evaluate the microstructure evolution of the blended elemental powder metallurgy Ti2AlNb alloy with a 2.0 wt% LaB6 addition and the effects of LaB6 doping on the microstructure and mechanical properties of the alloy. The results showed that the microstructure evolution could be divided into two stages. During the first stage, the reaction between Ti and Al powders was dominant. During the second stage, the Nb-enriched area disappeared gradually and microstructural homogeneity was enhanced with the diffusion of Nb. It was demonstrated that the LaB6 phase could be transformed into La2O3, (Ti, Nb)B and the (Ti, Nb)3B2 transition phase in the sintering process. LaB6 addition inhibited the precipitation of the brittle α2 phase and refined the microstructure. Compared with the alloy without LaB6, the Ti2AlNb alloy with 2 wt% LaB6 had 31.5% and 38.4% improvements in the fracture strain at 25 °C and 650 °C, respectively, and its yield strength was also increased.

Anatase TiO2 nanocrystalline film prepared by using sol–gel method was assembled on TiO2 nanotubes to produce composite thin film photocatalyst and investigated as interfacial layer for the catalytic performance of Ti/TNT/N–P/NaTaO3:La (the nanostructures is Ti/TiO2 nanotubes/TiO2 nanocrystalline film/NiO film/NaTaO3:La) photocatalyst to generate hydrogen and oxygen under UV irradiation. The as-synthesized samples were characterized by FESEM, XRD, Element Mapping, UV–Vis, PL, I–V, and EIS. Characteristic analyses show that the interface between the TNT layer (TiO2 nanotubes) and P layer (NiO film) can be optimized by adjusting the number of N layers (TiO2 nanocrystalline film), thus affecting the efficiency of the photocatalyst. Compared with unformed TiO2 film, the Ti/TNT/N–P/NaTaO3:La photocatalyst with four TiO2 layers enhanced the H2 and O2 generation rate from 43.7 to 87.1 μmol/h which realized almost 2.0 times. The enhanced photocatalytic performance can be attributed to the low defect density and the effective separation of photo-generated electron–hole pairs. Furthermore, the performance stability of thin film photocatalyst was favorably showcased through multiple water splitting reactions, and the rational mechanism of improved photocatalytic property was interpreted systematically. In summary, such results have certain guiding effect on solving the weakness of composite film catalyst of interface defects and carrier recombination.

Atomic-layered α-V2O5 nanosheets with a thickness of 5–7 layers were synthesized successfully via a fast gas-driven exfoliation process. The main advantages of this method are its more facile operation procedures, shorter preparation time, and higher yield. The obtained α-V2O5 nanosheets exhibit an enhanced aerobic oxidative desulfurization ability obviously. Sulfur removal of dibenzothiophene could reach up to 99.7% (less than 2 ppm) under optimized conditions.

Electrochemical water splitting is a promising technology to enable a sustainable energy supply; however, it remains a formidable challenge to find efficient and stable electrocatalysts. Particularly, oxygen evolution, the half-reaction at the anode, imposes serious overpotential penalties due to its sluggish kinetics. The continued rational design and optimization of OER catalysts via different strategies such as chemical substitution provide an understanding of the way that catalytic properties can be finely tuned. Here, we show a facile synthetic approach involving a Ce(NO3)3 precursor to yield a nitrogen and cerium co-doped CoS2 electrocatalyst. Remarkably, it requires an overpotential of only 190 mV to reach a current density of 10 mA cm−2 and exhibits long-term stability for 120 h. More importantly, a suite of advanced characterization techniques and theoretical calculations reveal complementary roles of the dual dopants which stabilize the intermediates as a result of the formation of two higher oxidation state metal active centers and maintain the surface structure. This work correlates the electronic structure and heteroatom doping, providing insights into electrochemical activity and stability and guiding the rational design of efficient electrocatalysts.

Infiltrated molten Al matrix by mechanical-pressure infiltration method into the ceramic scaffold prepared by freeze-drying technology could prepare dense lamellar Al matrix composites without damage of the biomimetic microstructure of the scaffold. However, the investigation of lamellar Al matrix composites prepared by freeze-drying and mechanical-pressure infiltration method has not been fully understood yet. In the present work, the Al2O3 scaffold with pearl layer structure was prepared by freezing-dry method, and eventually the lamellar Al2O3p/Al composite was fabricated by mechanical-pressure infiltration method. The Al matrix was infiltrated well into the large pores of the Al2O3 scaffold, and the lamellar structure of the Al2O3 was well preserved. The hardness of the lamellar Al2O3p/Al composite was isotropic in transvers and perpendicular directions. However, the compressive strengths of the lamellar Al2O3p/Al composite were significant anisotropic while the compressive strength in transvers direction was 127.7% higher than that in the perpendicular direction, indicating the integrality of the lamellae microstructure (especially the bridging layers). Due to the mismatched deformability, weak debonding was observed between Al and Al2O3p/Al layers in the fracture surface of the lamellar Al2O3p/Al composite. It indicates that the interfacial bonding between Al and Al2O3p/Al layers is rather strong, which is beneficial for higher strength in transvers direction but lead to lower strength in perpendicular direction.

Photocatalytic water splitting is a promising approach to convert solar energy into storable hydrogen fuel. In theory, the optimization of light-harvesting and catalytic molecular conversion ability is necessary for high-efficiency hydrogen evolution; however, the establishment of a photocatalytic system composed of a light-harvesting center and an active center is limited by poor light absorption capacity, high overpotential for catalytic conversion, as well as the low efficiency of charge transfer between the two components. In this work, we demonstrate that a high-efficiency photocatalytic system consisting of two-dimensional carbon nitride (2D-C3N4) as the light-harvester and nickel sulfide (NiSx) as the active component can serve as an efficient catalyst for hydrogen evolution, wherein the tight interface formed using two-step solvothermal treatment bridges the charge transfer. The 2D structure of 2D-C3N4 can shorten the charge migration distance from the bulk to the contact interface with NiSx and minimize the charge recombination in the light-harvesting center. NiSx with a highly active surface can capture the photo-generated electrons through a tight contact interface, completing the conversion from H+ to H2. As a result, the hydrogen evolution rate of the optimal NiSx/2D-C3N4 catalyst achieves a high value of ∼4640 μmol g−1 h−1 under visible light irradiation, which is more active than most of the Pt-free 2D-C3N4 supported photocatalysts under the same reaction conditions.

Graphene has extremely high theoretical strength and electrothermal properties, and its application to Cu-based composites is expected to achieve a breakthrough in the performance of existing composites. As a nano-reinforced body, graphene often needs a long time of ball milling to make it uniformly dispersed, but the ball milling process inevitably brings damage to the graphene, causing the performance of the composite to deviate from expectations. Therefore, this paper uses CH4 as a carbon source to repair graphene through a CVD process to prepare low-damage graphene/Cu composites. The process of graphene defect generation was studied through the ball milling process. The effects of defect content and temperature on the graphene repair process were studied separately. The study found that the graphene defect repair process, the decomposition process of oxygen-containing functional groups, and the deposition process of active C atoms existed simultaneously in the CVD process. When the repair temperature was low, the C atom deposition process and the oxygen-containing functional group decomposition process dominated. In addition, when the repair temperature is high, the graphene defect repair process dominated. 3 wt% graphene/Cu composites were prepared by pressure infiltration, and it was found that the bending strength was increased by 48%, the plasticity was also slightly increased, and the thermal conductivity was increased by 10–40%. This research will help reduce graphene defects, improve the intrinsic properties of graphene, and provide theoretical guidance for the regulation of C defects in composites.

Coral concrete has low cost and convenient materials, making it an excellent raw material for processing. However, its lower strength limits the application of coral concrete. Surface modification is expected to increase the properties of porous coral concrete. In this study, single and compound modification treatments were applied to the surface of a coral aggregate to improve its properties for promoting the mechanical performance of coral concrete. The results showed that the micro-aggregate effect and pozzolanic activity of granulated blast furnace slag (GBFS) and the permeability and polycondensation of sodium silicate (SS) could be mutually promoted. The GBFS and SS could effectively fill the pores of the coral aggregate, enhancing the properties of the aggregate, such as density and load-bearing capacity, and reducing the water absorption and crushing index by more than 50%. GBFS and SS could intensify and accelerate the hydration of cement, and generate a large number of hard hydration products at the interfacial transition zone (ITZ), which could strengthen the bonding between the aggregate and mortar, improving the strength of the ITZ. The compressive strength of the coral concrete was significantly increased.

Carbon nanotube (CNT) cathodes have attracted much attention in recent years due to the advantages of large field enhancement factor and low emission threshold. However, the severe ablation under intense emission makes the lifetime short and therefore limits the application in the field such as high power microwave generation. To resolve this problem, this paper proposes to mix CNTs with metals, and a novel CNT/Cu composite cathode is manufactured. The lifetime experiments under voltage of 940 kV and repetition frequency of 20 Hz demonstrate that the lifetime of the CNT/Cu composite cathode is over 3 × 105 pulses, which is much longer than that of the normal copper cathode by at least one order of magnitude. The microscopic morphology analysis reveals that the CNT micro-protrusions and whiskers should be vital for the good emission property of the new cathode.

The mechanical properties of (Ti, Nb)B/Ti2AlNb composites were expected to improve further by utilizing spark plasma sintering (SPS) and inducing the novel three-dimensional network architecture. In this study, (Ti, Nb)B/Ti2AlNb composites with the novel architecture were successfully fabricated by ball milling the LaB6 and Ti2AlNb mixed powders and subsequent SPS consolidation. The influence of the (Ti, Nb)B content on the microstructure and mechanical properties of the composites was revealed by using the scanning electron microscope (SEM), transmission electron microscopy (TEM) and electronic universal testing machine. The microstructural characterization demonstrated that the boride crystallized into a B27 structure and the α2-precipitated amount increased with the (Ti, Nb)B increasing. When the (Ti, Nb)B content reached 4.9 vol%, both the α2 and reinforcement exhibited a continuous distribution along the prior particle boundaries (PPBs). The tensile test displayed that the tensile strength of the composites presented an increasing trend with the increasing (Ti, Nb)B content followed by a decreasing trend. The composite with a 3.2 vol% reinforcement had the optimal mechanical properties; the yield strengths of the composite at 25 and 650 °C were 998.3 and 774.9 MPa, showing an 11.8% and 9.2% improvement when compared with the Ti2AlNb-based alloy. Overall, (Ti, Nb)B possessed an excellent strengthening effect and inhibited the strength weakening of the PPBs area at high temperatures; the reinforcement content mainly affected the mechanical properties of the (Ti, Nb)B/Ti2AlNb composites by altering the α2-precipitated amount and the morphology of (Ti, Nb)B in the PPBs area. Both the continuous precipitation of the brittle α2 phase and the agglomeration of the (Ti, Nb)B reinforcement dramatically deteriorated the mechanical properties.

Silane coupling agent (SCA), a kind of organic solvent, was introduced to improve the performance of coral coarse aggregates and enhance the interfacial adhesion between the inorganic coral aggregate and the cement paste of coral concrete. The crushing indicator and water absorption of the coral aggregates over various dipping times were measured, and the slump, interface microhardness, and compressive strength of coral concrete tested. The microscopic appearances of the coral concrete before and after modification were analyzed based on SEM images. The experimental results indicate that SCA can effectively reduce the crushing indicator and water absorption of coral coarse aggregates, and the modification performance becomes better over time. SCA facilitates the generation of chemical forces between the coral aggregates and cement mortars, improves adhesion between the aggregates and mortars, augments the microhardness of the interface, and increases the compressive strength. According to the microscopic appearance of the treated and untreated coral aggregate interfaces, the aggregates and the mortars are in closer combination after modification.