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This study aims to develop a facile ligand-exchange strategy to promote nano-sintering of oleylamine (OAM)-capped silver nanoparticles (AgNPs). By using ligand exchange process with NH₄OH to remove OAM from the surface of AgNP, this study reports effectively reducing the sintering temperature of AgNPs to achieve low-temperature nano-sintering. Compared with untreated AgNPs of OAM-capped, NH₄OH-treated AgNPs possess superior sintering performance that could be applied to a fractional generator device as conductor and in favour of the fabrication of flexible circuit modules.

First, oleylamine is used as reductant to synthesize monodisperse AgNPs by a simple one-step method. Then ligand exchange is used with NH₄OH at different treating times to remove OAM, and micro-Fourier transform infrared spectroscopy and contact angle test are applied to clear the mechanism and structure characteristics of these processes. Finally, NH₄OH-treated AgNPs sediment sintering is used at different temperatures to test electrical resistivity and use ex situ scanning electron microscopy combined with in situ X-ray diffraction to study changes in microstructure in the whole nano-sintering process.

The AgNPs are always capped by organic ligands to prevent nanoparticles agglomeration. And oleylamine used as reductant could synthesize desirable size distributions of 8–32 nm with monodisperse globular shapes, but the low-temperature nano-sintering seemed not to be achieved by the oleylamine-capped AgNPs because OAM is an organic with long C-chain. The ligand exchange approach was enabled to replace the original organic ligands capped on AgNPs with organic ligands of low thermal stability which could promote nano-sintering. After ligand exchange treated AgNPs could be sintered on photo paper, polydimethylsiloxane (PDMS) and polyethylene terephthalate flexible substrates at low temperature.

In this research, the method ligand exchange is used to change the ligand of AgNPs. During ligand exchange, NH₄OH was used to treat AgNPs. Through the treatment of NH₄OH, the change of hydrophilic and hydrophobic properties of AgNPs was successfully realized. The sintering temperature of AgNPs can also be reduced and the properties can be improved. Finally, the applicability of the AgNPs sediment with this nano-sintering process at low temperature for obtaining conductive patterns was evaluated using PDMS as substrates.

With the rapid development of the economy in China, the wealth of residents has continued to increase, and most families have gradually been aware of the importance of commercial insurance. The family purchase of insurance in China was still not optimistic. Many scholars focus on wealth allocation, but the attention to the commercial insurance market was still less. Based on previous research studies, this study aims to investigate the impact of education and financial literacy on the commercial insurance purchase in China.

China Household Finance Survey data was used to investigate the purchase of commercial insurance in Mainland Chinese families. Factor analysis was used to construct financial literacy, and the education data were combined to analyze the commercial insurance purchase using the Probit model and the Tobit model. Finally, the contributions of education and financial literacy to commercial insurance purchases were analyzed.

Both education and financial literacy exerted a positive impact on the purchase of commercial insurance in China. Individual characteristics such as gender, age, marital status, risk attitude, purchase of social insurance and consultation with a financial advisor possessed significant effects; household factors like household size and assets, macro factors such as the density of financial institutions and the density of financial industry staff, and regional factors as local unemployment rate excreted influences on the commercial insurance purchase.

Based on the current economic development in China, this study investigated and expressed opinions on the public and insurance companies regarding commercial insurance purchases. It accentuated financial literacy and education as factors that facilitated commercial insurance development.

The purpose of this paper is to investigate the effect of hexagonal boron nitride (h-BN) and poly (phenyl p-hydroxybenzoate) (PHBA) on improving the torsional tribological behavior of polytetrafluoroethylene (PTFE).

This paper investigates the torsional tribological behavior of PTFE composites filled with h-BN and PHBA under different angular displacements with a plane-on-plane torsional friction tester. The worn surface of PTFE composites was investigated by using a scanning electron microscope.

The shape of T–Θ curves of PTFE composites was influenced by both content fillers and torsional angule. The material with a higher coefficient of sliding friction exhibited the larger torsional angle under which the torsional regime transited from a partial slip to a gross slip. PTFE composites filled with 20 weight per cent PHBA and 10 weight per cent h-BN showed the best anti-wear properties. The specific wear rate of composites exhibits a negative correlation with material hardness. The wear volume loss presents a positive correlation with friction dissipation energy. The specific wear rate of all composites decreased with increasing torsional angle. The dominant wear mechanism of pure PTFE was adhesive wear. The slight plastic flow and plowing occurred on the worn surfaces of PTFE composites because of the higher hardness of composites and the lubrication of h-BN particles with layer crystal structure.

This paper put forward a kind of PTFE composite with low torsional wear rate, which can be used in the sliding slewing bearing or the center plate of a bogie.

This paper analyses container throughput developments in the East Asia container port system. Throughput evolutions and concentration/deconcentration patterns in the multi-range container port system of East Asia are analysed. The paper also provides a more in-depth qualitative analysis of the reasons underlying the observed trends and results. It is demonstrated that the East Asian port system is undergoing major structural shifts in cargo patterns and is witnessing a cargo deconcentration trend as a result of the rise of the Chinese ports and the relative stagnation of the Japanese range.

This study aims to enhance evacuation safety and efficiency measures in primary school corridors by considering the impact of adult guidance and evacuation graphical signs on evacuation speed and density by considering different visibility conditions and corridor design.

The experiment setup involved ten carefully designed drills exploring the evacuation behavior of 6–7-year-old students in a primary school, varying factors such as adult guidance, smoke conditions and graphical evacuation signs. Kinovea software was employed for data extraction to transform video footage into frames, facilitating meticulous manual tallies of children’s movements in designated sub-areas during the drills. The research utilized statistical tests, a generalized linear model and curve-fitting techniques to analyze the extracted data.

The findings highlight the vital role of adult guidance in expediting evacuations, emphasizing the importance of trained personnel during emergencies. Additionally, graphical evacuation signs were identified as powerful tools for enhancing evacuation speed during low visibility, as they provide clear visual cues to guide evacuees effectively. Signage and adult guidance are beneficial when the classrooms’ gates opening to the passage are far from each other. In contrast, in areas with close and multiple exits, guidance strategies, especially those involving adults, are more effective in reducing population density during evacuations.

These findings have practical implications for improving emergency preparedness, guiding the design of primary school corridors and informing evacuation protocols. School administrators, architects and emergency planners can utilize these findings to inform the development of safety protocols, enhance evacuation guidance strategies and improve the design of primary school corridors. Further research can expand on these findings by exploring their applicability in diverse educational settings and evaluating the real-world implementation of evacuation measures.

This study aims to investigate a chromium-free sealing treatment process to replace the chromate sealing process in response to the environmental hazards caused by chromate in the Phosphate chemical conversion (PCC) coating post-treatment sealing process.

In this paper, chromium-free sealing technology was used to post-treat PCC coatings. Scanning electron microscopy was used to investigate the structure of the surface of the PCC coatings after the sealing treatment, and the corrosion resistance, hydrophobicity and bonding were tested using an electrochemical workstation, a copper sulfate spot-drop test, a lacquer bonding test, a contact angle meter and a neutral salt spray test.

Chromium-free closure makes the grain distribution on the surface of the PCC coating more uniform and dense, and forms an organic film on the surface of the coating, which significantly improves the corrosion resistance and hydrophobicity of the PCC coating, does not affect the coating film bonding force and has similar performance with potassium dichromate solution.

The results show that the corrosion resistance of PCC coatings after chromium-free sealing treatment is improved, and chromium-free sealing has the potential to replace chromium sealing.