This research was conducted to investigate the ductility behavior of timber beams strengthened with CFRP (carbon fiber reinforced polymer) plates. The surface to be bonded was spiked by punching small holes of 2 mm ...This research was conducted to investigate the ductility behavior of timber beams strengthened with CFRP (carbon fiber reinforced polymer) plates. The surface to be bonded was spiked by punching small holes of 2 mm in diameter with 10 mm spacing. The aim is to increase bonding capacity by having small studs. Five beams with the dimension of 100 mm x 200 mm x 3,000 mm were tested where one of the beams was used as control beam (unstrengthened). The remaining beams were strengthened with different configurations before tested to failure under four-point loading. The results showed that the ductility was increased as the percentage of CFRP increased. The ductility was dramatically improved where the highest ductility index based on deflection method was 2.2 where the percentage increase was 37.5%, whereas the highest ductility index based on energy method was 3.2 where the percentage increase was 88.2%. From this study, it was found that 0.3% is the optimum value of CFRP area to achieve maximum ductility index. Ductility index obtained from energy method gives higher values when compared to deflection method. All beams in this study did not fail due to peel off or debonding. It was also proved that the spikes that have been made at the wood surface were very effective for bonding.展开更多
The article analysis of construction surface decoration quality, construction interior wall decoration quality, the construction of exterior wall tile adhesive quality and construction of aluminium alloy exterior qual...The article analysis of construction surface decoration quality, construction interior wall decoration quality, the construction of exterior wall tile adhesive quality and construction of aluminium alloy exterior quality problems, and points out the corresponding prevention measures on the problem. Finally, for wall cracks, the paper put forward the improvement measures.展开更多
The surface of a peach is known to exhibit spe- cial wettability and adhesion behaviors. We disclose that the peach surface is covered with long and short indumentums. The long indumentums are covered mainly with hydr...The surface of a peach is known to exhibit spe- cial wettability and adhesion behaviors. We disclose that the peach surface is covered with long and short indumentums. The long indumentums are covered mainly with hydrophobic wax molecules, while the short indumentums are coated mostly with hydrophilic polysaccharides. Thus, the peach surface exhibits a quasi-superhydrophobic property and high adhesive force. A water droplet on the surface of a peach is a quasi-sphere, which is unable to roll off even when the peach is turned upside down. This is defined as the peach skin effect. We present that the quasi-superhydrophobic state with high adhesive force is attributed to the special coexisting Wenzel's and Cassie's state for water droplets, thus creating the strong interaction between the water droplet and surface.展开更多
Development of highly efficient photocatalysts has emerged as a research hotspot because of their crucial role in affecting the conversion efficiency of solar energy for applications in resource exploitation and envir...Development of highly efficient photocatalysts has emerged as a research hotspot because of their crucial role in affecting the conversion efficiency of solar energy for applications in resource exploitation and environmental purification.The photocatalytic performance of the photocatalysts basically depends on the behaviors of light absorption,charge generation and separation,surface property and structural stability.Owing to its unique advantages(high surface area,tunable porosity,modifiable surface),porous silica provides an interesting platform to construct well-defined nanostructures such as core-shell,yolk-shell and other specific structures which effectively improved one or more of the above behaviors for photocatalysis.Typically,the structure with hollow morphology favors the light scattering and enlargement of surface area,while coating or binding with silica can modify the surface property of a photocatalyst to enhance the surface adsorption of reactants and physicochemical stability of catalysts.This review discusses the recent advances in the design,synthesis,formation mechanism of well-defined silica-based nanostructures,and the achievements of desired physicochemical properties for regulating the photocatalytic performance.展开更多
Poly(N-isopropylacrylamide)(PNIPAAm)-based thermo-responsive surfaces can switch their wettability(from wettable to non-wettable) and adhesion(from sticky to non-sticky) according to external temperature changes. Thes...Poly(N-isopropylacrylamide)(PNIPAAm)-based thermo-responsive surfaces can switch their wettability(from wettable to non-wettable) and adhesion(from sticky to non-sticky) according to external temperature changes. These smart surfaces with switchable interfacial properties are playing increasingly important roles in a diverse range of biomedical applications; these controlling cell-adhesion behavior has shown great potential for tissue engineering and disease diagnostics. Herein we reviewed the recent progress of research on PNIPAAm-based thermo-responsive surfaces that can dynamically control cell adhesion behavior. The underlying response mechanisms and influencing factors for PNIPAAm-based surfaces to control cell adhesion are described first. Then, PNIPAAm-modified two-dimensional flat surfaces for cell-sheet engineering and PNIPAAm-modified three-dimensional nanostructured surfaces for diagnostics are summarized. We also provide a future perspective for the development of stimuli-responsive surfaces.展开更多
文摘This research was conducted to investigate the ductility behavior of timber beams strengthened with CFRP (carbon fiber reinforced polymer) plates. The surface to be bonded was spiked by punching small holes of 2 mm in diameter with 10 mm spacing. The aim is to increase bonding capacity by having small studs. Five beams with the dimension of 100 mm x 200 mm x 3,000 mm were tested where one of the beams was used as control beam (unstrengthened). The remaining beams were strengthened with different configurations before tested to failure under four-point loading. The results showed that the ductility was increased as the percentage of CFRP increased. The ductility was dramatically improved where the highest ductility index based on deflection method was 2.2 where the percentage increase was 37.5%, whereas the highest ductility index based on energy method was 3.2 where the percentage increase was 88.2%. From this study, it was found that 0.3% is the optimum value of CFRP area to achieve maximum ductility index. Ductility index obtained from energy method gives higher values when compared to deflection method. All beams in this study did not fail due to peel off or debonding. It was also proved that the spikes that have been made at the wood surface were very effective for bonding.
文摘The article analysis of construction surface decoration quality, construction interior wall decoration quality, the construction of exterior wall tile adhesive quality and construction of aluminium alloy exterior quality problems, and points out the corresponding prevention measures on the problem. Finally, for wall cracks, the paper put forward the improvement measures.
基金supported by the National Natural Science Foundation of China(21103006)the Beijing Natural Science Foundation(2132030)+2 种基金the National High Technology Research and Development Program of China(2012AA030305)the Fundamental Research Funds for the Central Universities(YWF-10-01-B16,YWF-11-03-Q-214,YWF-13-DX-XYJL-004)the 111 Project(B14009)
文摘The surface of a peach is known to exhibit spe- cial wettability and adhesion behaviors. We disclose that the peach surface is covered with long and short indumentums. The long indumentums are covered mainly with hydrophobic wax molecules, while the short indumentums are coated mostly with hydrophilic polysaccharides. Thus, the peach surface exhibits a quasi-superhydrophobic property and high adhesive force. A water droplet on the surface of a peach is a quasi-sphere, which is unable to roll off even when the peach is turned upside down. This is defined as the peach skin effect. We present that the quasi-superhydrophobic state with high adhesive force is attributed to the special coexisting Wenzel's and Cassie's state for water droplets, thus creating the strong interaction between the water droplet and surface.
基金supported by the National Natural Science Foundation of China(21771070 and 21571071)the Fundamental Research Funds for the Central Universities(2018KFYYXJJ120 and 2019KFYRCPY104)。
文摘Development of highly efficient photocatalysts has emerged as a research hotspot because of their crucial role in affecting the conversion efficiency of solar energy for applications in resource exploitation and environmental purification.The photocatalytic performance of the photocatalysts basically depends on the behaviors of light absorption,charge generation and separation,surface property and structural stability.Owing to its unique advantages(high surface area,tunable porosity,modifiable surface),porous silica provides an interesting platform to construct well-defined nanostructures such as core-shell,yolk-shell and other specific structures which effectively improved one or more of the above behaviors for photocatalysis.Typically,the structure with hollow morphology favors the light scattering and enlargement of surface area,while coating or binding with silica can modify the surface property of a photocatalyst to enhance the surface adsorption of reactants and physicochemical stability of catalysts.This review discusses the recent advances in the design,synthesis,formation mechanism of well-defined silica-based nanostructures,and the achievements of desired physicochemical properties for regulating the photocatalytic performance.
基金supported by the National Basic Research Program of China(2012CB933800,2011CB935700,2012CB933200)the National Natural Science Foundation of China(21175140,20974113,21121001)the Key Research Program of the Chinese Academy of Sciences(KJZD-EW-M01)
文摘Poly(N-isopropylacrylamide)(PNIPAAm)-based thermo-responsive surfaces can switch their wettability(from wettable to non-wettable) and adhesion(from sticky to non-sticky) according to external temperature changes. These smart surfaces with switchable interfacial properties are playing increasingly important roles in a diverse range of biomedical applications; these controlling cell-adhesion behavior has shown great potential for tissue engineering and disease diagnostics. Herein we reviewed the recent progress of research on PNIPAAm-based thermo-responsive surfaces that can dynamically control cell adhesion behavior. The underlying response mechanisms and influencing factors for PNIPAAm-based surfaces to control cell adhesion are described first. Then, PNIPAAm-modified two-dimensional flat surfaces for cell-sheet engineering and PNIPAAm-modified three-dimensional nanostructured surfaces for diagnostics are summarized. We also provide a future perspective for the development of stimuli-responsive surfaces.