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There has been a devastating impact on small businesses around the world as a result of the COVID-19 virus pandemic. This study examined the many ways in which small businesses have been affected by the pandemic, the challenges they have encountered, and the strategies they have implemented to survive and grow. The epidemic has not only had far-reaching ramifications for small enterprises, but it has also had a catastrophic effect on the economy of the entire world. The fact that clients of small businesses are remaining at home and not spending money has presented them with a number of challenges, including an increased risk of failure, mental health difficulties, and the difficulty of adapting to the new digital world. It is imperative that governments all around the world take steps to provide assistance to local firms if these difficulties are going to be mitigated. This involves offering monetary support, access to money and funding, resources and knowledge, as well as training and mentorship programmes, and resources pertaining to mental health. In addition, governments should make it possible for small enterprises to gain access to legal assistance in order to better assist them in navigating the ever-shifting regulations and constraints imposed by governments. This will ensure that small businesses have access to the resources they require to not only survive but also grow in this new environment.

This study analyzes the implications of the Russia-Ukraine conflict on the international banking industry. The study establishes that the economic sanctions imposed on Russia have gravely affected the international banking sector. Primarily, the study highlights that the US government implemented a sanction that prohibits the Central Bank of Russia from using the US dollar for payments. This move has rendered all the reserves by the Russian government and its citizens, which are kept in US dollars worthless and inaccessible, leading to huge losses for domestic and international banks. Moreover, this study outlines that banning Russian financial institutions from using SWIFT has limited the financial payments that are being completed in the global banking sector between Russian consumers and companies, and other merchants across the world. This study also establishes that the withdrawal of services by Visa, MasterCard, American Express, and Paypal from the Russian economy as a protest against Russia’s invasion of Ukraine has led to a decline in revenues for international banks. As a measure to mitigate the adverse implications of economic sanctions on sovereign states in the future, the study suggests the adoption of diverse global payment systems such as CIPS and SPFS, which can cushion the international banking industry against the potential adverse effects of being denied the right to use the world's dominant currencies and the SWIFT messaging system to make payments.

The spark plasma sintering (SPS) technique was found to effectively improve the mechanical properties of TiB2–SiC ceramic by forming a unique interlocking structure. This study investigated the phase transition process of the hexagonal micro-platelets TiB2 powders with self-assembled structure during the molten-salt-mediated carbothermal reduction and its effect on promoting the mechanical properties of TiB2-based ceramics. It was found that the SPS approach ensured a highly densified TiB2–SiC ceramics with enhanced Vickers hardness of 21.0 ± 1.3 GPa and fracture resistance of 7.8 ± 0.3 MPa m1/2. The performance enhancement of the resultant TiB2–SiC composite was attributed to the interlocking structure from the original anisotropic TiB2 powders, which could effectively absorb the energy and facilitate the crack deflection.

Poor antioxidant and thermal-shock capacities of C/C composites thermal barrier coating (TBC) caused by cracking and shedding of coatings has been a major obstacle blocking the development of C/C composites. Herein, in-situ growth of whisker reinforced silicon carbide transition layer and inter-embedding mechanism of multi-gradient coatings were brought into the design of TBC to enhance the antioxidant and thermal-shock capacities. A three-layer gradient coating SiC-SiCw/ZrB2-SiC/ZrSiO4-aluminosilicate glass (ZAG) from inside to outside, in which ZrB2-SiC/ZAG serve as oxygen barrier layers with self-healing ability and SiC-SiCw provides thermal stress buffering and bonding against cracking and shedding of coatings, is designed. The ZAG mainly forms a dense oxygen blocking frontier with self-healing ability through fluidized glass, while the ZrB2-SiC can react actively with infiltrated oxygen in a way of self-sacrifice, preventing oxygen erosion to C/C matrix and SiC-SiCw transition layer. As a result, the collaborative work among layers endows this coating with excellent high temperature service performance. This work provides a new insight for the design of excellent TBC.

This study indicated that joining two different types of solid-state materials, co-doped lanthanum strontium chromium ferrite (LSCrF, La0.33Sr0.67Cr1-xFexO3-δ) perovskite oxide, and gadolinium-doped ceria (GDC, Ce0.9Gd0.1O2-δ) fluorite, yielded series of unique electrocatalytic composites, enabling a green production of ammonia (NH3, (g)) via nitrogen (N2, (g)) and steam (H2O, (g)) reaction at the cathode compartment. An optimized ball milling approach was implemented to produce the cathodic composites with different formulations to respond to the environmental stimuli changes of operational temperature and applied voltage. The solid oxide electrolysis cells (SOECs) were then assembled and used for NH3 production with optimized synthesis and electrochemical measurement variables. As a result, these engineered cathodic catalysts maximized the efficacy of NH3 production due to the formation of oxygen vacancies, high interactivity between catalysts and reactants, and gas channeling through the macro-porous structure. To tune the macro-porous structure of the cathodic composites, the group invented an in-situ templating using a porogen (PMMA, polymethylmethacrylate, (C5O2H8) n) with a controllable size to facilitate gas diffusion and adsorption along with the interfaces of phase boundaries. Electrochemical analyses such as the measurement of impedance demonstrated that the macro-porous structured (LSCrF-GDC) electrode exhibited superior electrocatalytic kinetics. Consequently, the formation rate of NH3 was found to achieve 3.0 × 10−10 mol⋅s-1⋅ cm-2 when the SOEC technology was implemented under an applied voltage of 1.8 V and operating temperature at 600 °C. The mechanistic study of electrochemical performance and interactivity between cathodic catalysts and reactants indicated that an optimized NH3 production pathway was carried out below thermoneutral enthalpy to achieve high efficiency. This goal was achieved through adjustment of the ratio between the enthalpy flow of produced hydrogen and the input of electrical power. The contribution of this study lies in the optimized methodology to enhance interactive electrocatalysis applied for the green synthesis of ammonia.

A series of silver (Ag)-modified barium cobalt ferrous niobate (Ba1-xCo0.7Fe0.2Nb0.1O3-δ, BCFN) materials were fabricated using a solid-state method by doping silver cations into the A-site of this perovskite matrix (Ag-BCFN). The electrochemical analyses indicated that the Ag-BCFN cathodic catalysts performed superior to the nonmodified catalysts when applied in intermediate-temperature solid oxide fuel cells (IT-SOFCs). These Ag-BCFN cathodic catalysts displayed a cubic perovskite structure (PDF 75-0227, Pm3m, α = 90°) with a high degree of crystallinity, as demonstrated by X-ray powder diffraction analyses. It was also found that the in situ exsolution of the silver ion (Ag+) occurred, where 57.9% of doped Ag+ was reduced into metallic Ag particles with size ranging from 5 to 10 nm, as shown by electron microscopic analyses. The cerium gadolinium oxide (Ce0.9Gd0.1O2-δ) electrolyte-supported symmetrical half cell using different Ag-BCFN formulations of Ba1-xAgxCo0.7Fe0.2Nb0.1O3-δ as electrodes showed a polarization resistance as low as 0.233 Ω·cm2 and an exchange current density of 85.336 mA·cm-2 at 650 °C under ambient pressure. The improved electrochemical kinetics is anticipated to be attributed to two reasons: doping of ions (Ag+) in the A-site of perovskite and in situ exsolved silver nanoparticles (Ag NPs) along the edge and on the surface of BCFNs improving the mobile charge and electrical properties of the material. The remaining Ag+ in the A-site induced the electron redistribution, whereas the Ag NPs were found to increase the electrochemically active sites and enable the formation of a triple-phase boundary. These explanations were confirmed by the density functional theory study, indicating that Ag-doping processes lead to a decrease in the formation energy of oxygen vacancies from 1.72 to 1.42 eV upon the partial substitution of Ba2+ by Ag+ cations.

A series of silver (Ag)-modified barium cobalt ferrous niobate (Ba

The absorption behavior of lattice oxygen for Ce0.8Y0.2O2–δ (YDC) crystal was investigated. Combined with TG-DSC, XRD, Raman and XPS characterization, lattice oxygen absorption occurs at intermediate temperature (from 500 to 800 °C), which is related to the oxygen vacancies consumption, and no phase change is observed in this process. In electric conductivity relaxation (ECR) experiment, prolonged oxygen diffusion process is observed above 600 °C, which may be caused by oxygen absorption process. And through ECR experiments, the bulk diffusion coefficient Dchem and surface exchange coefficient Kex for YDC dense sample are measured as 6.5 × 10−5–2 × 10−4 cm2/s and Kex = 2 × 10−4–9 × 10−4 cm/s at intermediate temperature range.

Friction self-piercing riveting (F-SPR) process has shown advantages over fusion welding, solid state welding, and traditional mechanical joining processes in joining dissimilar materials. Because of the thermo-mechanical nature of F-SPR process, formation of the joint is determined by both riveting force and softening degree of materials to be joined. However, it is still not clear that how exactly the riveting force and generated frictional heat jointly influence mechanical interlocking formation and crack inhibition during F-SPR process. To address these issues, F-SPR process was applied to join 2.2 mm-thick aluminum alloy AA6061-T6 to 2.0 mm-thick magnesium alloy AZ31B. The correlation of riveting force, torque responses, and energy input with joint quality was investigated systematically under a wide range of process parameter combinations. It was found that a relatively greater final peak force and higher energy input were favorable to produce sound joints. Based on that, a two-stage F-SPR method was proposed to better control the energy input and riveting force for improved joint quality. The joints produced by the two-stage method exhibited significantly improved lap-shear strength, i.e., 70% higher than traditional self-piercing riveting (SPR) joints and 30% higher than previous one-stage F-SPR joints. This research provides a valuable reference for further understanding the F-SPR joint formation mechanism and conducting process optimization.

Friction self-piercing riveting (F-SPR) process has been proposed to join low ductility lightweight materials, and has shown advantages over fusion welding, solid state welding and traditional mechanical joining processes in joining dissimilar as well as low ductility materials. Because of the thermo-mechanical nature of F-SPR process, the formation of the joint is determined by riveting force and softening degree of the materials. However, it is still not clear that how exactly the riveting force and generated frictional heat jointly influence the mechanical interlocking formation and inhibit cracks during F-SPR process. To address these issues, in current study, F-SPR process was applied to join 2.2 mm-thick AA6061-T6 aluminum alloy to 2.0 mm-thick AZ31B magnesium alloy. The correlation of riveting force, torque responses as well as energy input with joint quality were investigated systematically under a wide range of process parameter combinations. It was found that a relatively greater final peak force and higher energy input were favorable to produce sound joints. Based on that, a two-stage method was proposed to better control the energy input and riveting force. It was found that the joints produced by the two-stage method exhibited significantly improved lap-shear strength, i.e., 70% higher than traditional SPR joints and 30% higher than one-stage F-SPR joints. This research provides a valuable reference for further understanding the F-SPR joint formation and process optimization.