The use of a glass-fiber reinforced composite in marine structures is becoming more common, particularly due to the potential weight savings. The mechanical response of the joint between a glass-fiber reinforced polym...The use of a glass-fiber reinforced composite in marine structures is becoming more common, particularly due to the potential weight savings. The mechanical response of the joint between a glass-fiber reinforced polymer (GRP) superstructure and a steel hull formed is examined and subsequently modified to improve performance through a combined program of modeling and testing. A finite-element model is developed to predict the response of the joint. The model takes into account the contact at the interface between different materials, progressive damage, large deformation theory, and a non-linear stress-strain relationship. To predict the progressive failure, the analysis combines Hashin failure criteria and maximum stress failure criteria. The results show stress response has a great influence on the strength and bearing of the joint. The Balsawood-steel interface is proved to be critical to the mechanical behavior of the joint. Good agreement between experimental results and numerical predictions is observed.展开更多
The effects of Ethylene-Vinyl Acetate copolymer (EVA) latex as an additive or a glass fiber surface modifier on the properties of Glass-Fiber ( GF )/ Magnesium Oxychloride Cement (MOC) composites was studied. Th...The effects of Ethylene-Vinyl Acetate copolymer (EVA) latex as an additive or a glass fiber surface modifier on the properties of Glass-Fiber ( GF )/ Magnesium Oxychloride Cement (MOC) composites was studied. The mechanical properties, water resistance aud aging resistance of the cured GF/ MOC composites were estimated and chemical ingredients analysis and morphological study of the GF/ MOC composites were also performed. It is found that EVA added to the MOC matrix could substantially improve the interfacial adhesion, water resistance aud aging resistance of GF/ MOC composites. EVA treatment on glass fibers resulted in decreasing initial flexural strength of GF/ MOC composites while enhancing the soft coefficients. In addition, the drying time and dilution of the EVA treatment on glass fibers also had an otwioas effect on the properties of GF/ MOC composites. However, excessive EVA interfered with the growth of the 5 Mg( OH)2· MgCl2 ·8H2O crystal and the properties of GF / MOC composites.展开更多
Samples of cerium-manganese oxides supported on modified glass-fiber with different Ce/Mn molar ratios (Ce-Mn/GF) were prepared by an impregnation method and tested for low-temperature (80 180 ℃) selective cataly...Samples of cerium-manganese oxides supported on modified glass-fiber with different Ce/Mn molar ratios (Ce-Mn/GF) were prepared by an impregnation method and tested for low-temperature (80 180 ℃) selective catalytic reduction (SCR) of NO with ammonia. This brand-new technology could remove NO and particles matter from coal-fired flue gas. The surface properties of the catalysts were examined by means of Bmnauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The experimental results showed that the catalyst with a Ce/Mn molar ratio of 0.2 obtained high activity of 87.4% NO conversion at 150 ℃ under a high space velocity of 50000 h1. Deactivation poisoned by SO2 still occurred, but the Ce-Mn/GF(0.2) catalyst performed desirable tolerance to SO2 with decreasing 50% in 40 min and then maintaining at about 30% NO conversion. Characterization results indicated that the excellent low-temperature catalytic activity was related to the high specific surface area, pore structure, and amorphous phase.展开更多
基金Foundation item: Supported by the National Natural Science Foundation of China (Grant No 61004008), the Central Universities under Grant HEUCFR1001 and LBH-10138 Higher Sliding Mode Control for Underactuated Surface Ship.
文摘The use of a glass-fiber reinforced composite in marine structures is becoming more common, particularly due to the potential weight savings. The mechanical response of the joint between a glass-fiber reinforced polymer (GRP) superstructure and a steel hull formed is examined and subsequently modified to improve performance through a combined program of modeling and testing. A finite-element model is developed to predict the response of the joint. The model takes into account the contact at the interface between different materials, progressive damage, large deformation theory, and a non-linear stress-strain relationship. To predict the progressive failure, the analysis combines Hashin failure criteria and maximum stress failure criteria. The results show stress response has a great influence on the strength and bearing of the joint. The Balsawood-steel interface is proved to be critical to the mechanical behavior of the joint. Good agreement between experimental results and numerical predictions is observed.
文摘The effects of Ethylene-Vinyl Acetate copolymer (EVA) latex as an additive or a glass fiber surface modifier on the properties of Glass-Fiber ( GF )/ Magnesium Oxychloride Cement (MOC) composites was studied. The mechanical properties, water resistance aud aging resistance of the cured GF/ MOC composites were estimated and chemical ingredients analysis and morphological study of the GF/ MOC composites were also performed. It is found that EVA added to the MOC matrix could substantially improve the interfacial adhesion, water resistance aud aging resistance of GF/ MOC composites. EVA treatment on glass fibers resulted in decreasing initial flexural strength of GF/ MOC composites while enhancing the soft coefficients. In addition, the drying time and dilution of the EVA treatment on glass fibers also had an otwioas effect on the properties of GF/ MOC composites. However, excessive EVA interfered with the growth of the 5 Mg( OH)2· MgCl2 ·8H2O crystal and the properties of GF / MOC composites.
基金Project supported by the National High Technology Research and Development Program of China(863 Program)(2008AA05Z305)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry(201109)+2 种基金the Master Dissertation Innovation Funded Projects(EG2013015)the Fundamental Research Funds for the Central Universities Special Fund Project(11D11315)Program of Shanghai Subject Chief Scientist(14XD1424700)
文摘Samples of cerium-manganese oxides supported on modified glass-fiber with different Ce/Mn molar ratios (Ce-Mn/GF) were prepared by an impregnation method and tested for low-temperature (80 180 ℃) selective catalytic reduction (SCR) of NO with ammonia. This brand-new technology could remove NO and particles matter from coal-fired flue gas. The surface properties of the catalysts were examined by means of Bmnauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The experimental results showed that the catalyst with a Ce/Mn molar ratio of 0.2 obtained high activity of 87.4% NO conversion at 150 ℃ under a high space velocity of 50000 h1. Deactivation poisoned by SO2 still occurred, but the Ce-Mn/GF(0.2) catalyst performed desirable tolerance to SO2 with decreasing 50% in 40 min and then maintaining at about 30% NO conversion. Characterization results indicated that the excellent low-temperature catalytic activity was related to the high specific surface area, pore structure, and amorphous phase.