This article presents experimental results of steel-timber-steel(STS)joints loaded parallel to grain.Eight groups of specimens were designed,and tensile tests were performed.The fastener types and fastener numbers wer...This article presents experimental results of steel-timber-steel(STS)joints loaded parallel to grain.Eight groups of specimens were designed,and tensile tests were performed.The fastener types and fastener numbers were considered to evaluate the tensile strengths and ductility performances of the STS joints.The screws with 6 mm diameter and the innovative steel-tubes with 18 mm diameter were adopted as connecting fasteners.The experimental results were discussed in terms of yielding and ultimate strengths,slip stiffness,and ductility factors.The ductility classification and failure mechanisms of each group of specimens were analyzed.It was demonstrated that the STS joint with large diameter steel-tubes showed acceptable ductility,which was close to the ductility of the STS joint with small diameter screws,thanks to the hollow structure of the steel-tube.The theoretical strengths of various failure modes for the joints with small diameter screws or large diameter steel-tubes were calculated and compared with the experimental results.The ductile performance of the STS joint was discussed by comparing the theoretical strengths of various failure modes.The effective number of the STS joint with multifasteners was also analyzed by considering the failure mechanisms in aspects of tensile strength and slip stiffness.展开更多
Introduction: The stability of orthodontic brackets throughout orthodontic treatment plays a critical role in the treatment’s effectiveness. The present in vitro study was designed to assess the impact of various die...Introduction: The stability of orthodontic brackets throughout orthodontic treatment plays a critical role in the treatment’s effectiveness. The present in vitro study was designed to assess the impact of various dietary components on the performance of orthodontic brackets. Methods: Metal orthodontic brackets were bonded to 66 extracted anterior teeth divided into groups based on the solution type: Milk, Gatorade, Cold Coffee, and a control group using water. Each group consisted of 20 teeth except for the control group, which included six teeth. The bracketed teeth were submerged in their respective solutions for 15 minutes three times daily at different intervals to mimic an in vivo environment and were stored in artificial saliva at room temperature (23?C). The specimens underwent artificial aging through 10,000 cycles of thermocycling (representing one clinical year) between 5?C and 55?C. Shade measurements were taken using a VITA Easy Shade device, capturing the classic shade and L*, a*, and b* values. Delta E values were calculated immediately post-bonding and after 7 days, 1 month, 1, and 2 clinical years. The shear bond strength of each bracket was measured using an ultra-tester machine. Results: After two clinical years, significant differences in ΔE color values were observed across all groups, with the most substantial change noted in teeth immersed in cold coffee. Brackets submerged in milk demonstrated lower shear bond strength than other solutions, whereas the control group exhibited the highest shear bond strength (P = 0.01). Conclusion: The study indicates that dietary components significantly influence tooth color stability and the shear bond strength of orthodontic brackets, underscoring the importance of considering these factors in orthodontic treatment planning.展开更多
With the increasing global demand for renewable energy,solar photovoltaic power generation technology has been widely applied in China and even globally.Especially in mountainous areas,complex terrain resources are cl...With the increasing global demand for renewable energy,solar photovoltaic power generation technology has been widely applied in China and even globally.Especially in mountainous areas,complex terrain resources are cleverly utilized in the construction of photovoltaic power stations,but this also brings severe challenges to the anti-corrosion of photovoltaic brackets.This paper focuses on the anti-corrosion technology of mountain photovoltaic brackets,and deeply explores the influence of natural factors such as mountain climate,sandstorms,and precipitation on the corrosion of photovoltaic brackets.The research results show that the key to improving anti-corrosion performance lies in the selection of bracket materials and optimization of coating processes.After comparing various anti-corrosion treatment methods such as hot-dip galvanizing,spray aluminum coating,and new anti-corrosion materials,it is found that nano coating technology exhibits excellent protective effects in corrosive environments.This study is of great significance for promoting the sustainable development of photovoltaic power generation,providing solid theoretical support and practical guidance for the anti-corrosion design of mountain photovoltaic power stations.展开更多
The Bracket Set(dougong)is an important aspect of traditional Chinese architecture known for its exquisite structure,complexity,and rich variations.This design element has been used since the Qin and Han Dynasties and...The Bracket Set(dougong)is an important aspect of traditional Chinese architecture known for its exquisite structure,complexity,and rich variations.This design element has been used since the Qin and Han Dynasties and is still prevalent today.It highlights hierarchy and spiritual connotations in the design of a building.This article explores the application of Bracket Set elements in modern architectural design.It analyzes the specific application strategies of this design element,highlighting its value in modern architecture.The goal is to provide modern architectural designers with multiple perspectives and strategies to fully utilize the advantages of Bracket Set elements in architectural design and enhance the artistic value of their work.展开更多
基金supported by National Natural Science Foundation of China(Grant Nos.52208253,51878344)Postdoctoral Foundation of Jiangsu Province(Grant No.2021K128B)Jiangsu Funding Program for Excellent Postdoctoral Talent,which are highly appreciated.
文摘This article presents experimental results of steel-timber-steel(STS)joints loaded parallel to grain.Eight groups of specimens were designed,and tensile tests were performed.The fastener types and fastener numbers were considered to evaluate the tensile strengths and ductility performances of the STS joints.The screws with 6 mm diameter and the innovative steel-tubes with 18 mm diameter were adopted as connecting fasteners.The experimental results were discussed in terms of yielding and ultimate strengths,slip stiffness,and ductility factors.The ductility classification and failure mechanisms of each group of specimens were analyzed.It was demonstrated that the STS joint with large diameter steel-tubes showed acceptable ductility,which was close to the ductility of the STS joint with small diameter screws,thanks to the hollow structure of the steel-tube.The theoretical strengths of various failure modes for the joints with small diameter screws or large diameter steel-tubes were calculated and compared with the experimental results.The ductile performance of the STS joint was discussed by comparing the theoretical strengths of various failure modes.The effective number of the STS joint with multifasteners was also analyzed by considering the failure mechanisms in aspects of tensile strength and slip stiffness.
文摘Introduction: The stability of orthodontic brackets throughout orthodontic treatment plays a critical role in the treatment’s effectiveness. The present in vitro study was designed to assess the impact of various dietary components on the performance of orthodontic brackets. Methods: Metal orthodontic brackets were bonded to 66 extracted anterior teeth divided into groups based on the solution type: Milk, Gatorade, Cold Coffee, and a control group using water. Each group consisted of 20 teeth except for the control group, which included six teeth. The bracketed teeth were submerged in their respective solutions for 15 minutes three times daily at different intervals to mimic an in vivo environment and were stored in artificial saliva at room temperature (23?C). The specimens underwent artificial aging through 10,000 cycles of thermocycling (representing one clinical year) between 5?C and 55?C. Shade measurements were taken using a VITA Easy Shade device, capturing the classic shade and L*, a*, and b* values. Delta E values were calculated immediately post-bonding and after 7 days, 1 month, 1, and 2 clinical years. The shear bond strength of each bracket was measured using an ultra-tester machine. Results: After two clinical years, significant differences in ΔE color values were observed across all groups, with the most substantial change noted in teeth immersed in cold coffee. Brackets submerged in milk demonstrated lower shear bond strength than other solutions, whereas the control group exhibited the highest shear bond strength (P = 0.01). Conclusion: The study indicates that dietary components significantly influence tooth color stability and the shear bond strength of orthodontic brackets, underscoring the importance of considering these factors in orthodontic treatment planning.
文摘With the increasing global demand for renewable energy,solar photovoltaic power generation technology has been widely applied in China and even globally.Especially in mountainous areas,complex terrain resources are cleverly utilized in the construction of photovoltaic power stations,but this also brings severe challenges to the anti-corrosion of photovoltaic brackets.This paper focuses on the anti-corrosion technology of mountain photovoltaic brackets,and deeply explores the influence of natural factors such as mountain climate,sandstorms,and precipitation on the corrosion of photovoltaic brackets.The research results show that the key to improving anti-corrosion performance lies in the selection of bracket materials and optimization of coating processes.After comparing various anti-corrosion treatment methods such as hot-dip galvanizing,spray aluminum coating,and new anti-corrosion materials,it is found that nano coating technology exhibits excellent protective effects in corrosive environments.This study is of great significance for promoting the sustainable development of photovoltaic power generation,providing solid theoretical support and practical guidance for the anti-corrosion design of mountain photovoltaic power stations.
文摘The Bracket Set(dougong)is an important aspect of traditional Chinese architecture known for its exquisite structure,complexity,and rich variations.This design element has been used since the Qin and Han Dynasties and is still prevalent today.It highlights hierarchy and spiritual connotations in the design of a building.This article explores the application of Bracket Set elements in modern architectural design.It analyzes the specific application strategies of this design element,highlighting its value in modern architecture.The goal is to provide modern architectural designers with multiple perspectives and strategies to fully utilize the advantages of Bracket Set elements in architectural design and enhance the artistic value of their work.
