Styrene-acrylate latex with high glass transition temperature (T), low minimum film forming temperature(MFT) and good stability was prepared via core-shell emulsion polymerization. With semicontinuous process, hig...Styrene-acrylate latex with high glass transition temperature (T), low minimum film forming temperature(MFT) and good stability was prepared via core-shell emulsion polymerization. With semicontinuous process, high conversion rate of monomer and low gel rate were achieved. The weight ratio of core monomer to shell monomer was approximately 1.35. It is found that many factors such as emulsifiers, initiators, reaction temperature, pH value and polymerization technology have influences on the permormance of styrene-acrylate latex. The prepared latex was characterized by TEM and FTIR. The obtained latex with T of 20.57 ℃, MFT or5.0 ℃, and good stability, had good stability of film forming.展开更多
Good morning, ladies and gentlemen,
In the golden autumn of Beijing, on behalf of the Organizing Committee of the Great Wall International Congress of Cardiology, and the Institute of Geriatric Cardiology at ... Good morning, ladies and gentlemen,
In the golden autumn of Beijing, on behalf of the Organizing Committee of the Great Wall International Congress of Cardiology, and the Institute of Geriatric Cardiology at Chinese PLA General Hospital, I am very delighted to extend my warmest welcome to the representatives, colleagues and distinguished guests, both domestic and abroad, to the 5th International Forum on Geriatric Cardiology.……展开更多
Flow and physical properties were measured for three fuel powders: sawdust, brown coal and hard coal. Besides physical properties, e.g., particle size, bulk density and moisture content, flowability was investigated ...Flow and physical properties were measured for three fuel powders: sawdust, brown coal and hard coal. Besides physical properties, e.g., particle size, bulk density and moisture content, flowability was investigated using the standard shear testing technique of the Jenike shear cell. Flow functions of the three powders used for characterization of bulk flow and design of hoppers were determined, and then compared and discussed. The flow functions of the three powders are located in different regions: while brown coal and hard coal were classified respectively as easy flowing and cohesive material, sawdust was found in regions varying from cohesive to easy fowing at low consolidation stress. The measured effective angle of internal friction and angle of wall friction were 55° and 31.4° for sawdust; 36.2° and 26° for brown coal; and 43.3° and 27.8° for hard coal. Using the measured powder flow properties, Jenike's procedure was then followed to estimate and compare the critical hopper dimensions for mass flow of the three powders.展开更多
文摘Styrene-acrylate latex with high glass transition temperature (T), low minimum film forming temperature(MFT) and good stability was prepared via core-shell emulsion polymerization. With semicontinuous process, high conversion rate of monomer and low gel rate were achieved. The weight ratio of core monomer to shell monomer was approximately 1.35. It is found that many factors such as emulsifiers, initiators, reaction temperature, pH value and polymerization technology have influences on the permormance of styrene-acrylate latex. The prepared latex was characterized by TEM and FTIR. The obtained latex with T of 20.57 ℃, MFT or5.0 ℃, and good stability, had good stability of film forming.
文摘 Good morning, ladies and gentlemen,
In the golden autumn of Beijing, on behalf of the Organizing Committee of the Great Wall International Congress of Cardiology, and the Institute of Geriatric Cardiology at Chinese PLA General Hospital, I am very delighted to extend my warmest welcome to the representatives, colleagues and distinguished guests, both domestic and abroad, to the 5th International Forum on Geriatric Cardiology.……
文摘Flow and physical properties were measured for three fuel powders: sawdust, brown coal and hard coal. Besides physical properties, e.g., particle size, bulk density and moisture content, flowability was investigated using the standard shear testing technique of the Jenike shear cell. Flow functions of the three powders used for characterization of bulk flow and design of hoppers were determined, and then compared and discussed. The flow functions of the three powders are located in different regions: while brown coal and hard coal were classified respectively as easy flowing and cohesive material, sawdust was found in regions varying from cohesive to easy fowing at low consolidation stress. The measured effective angle of internal friction and angle of wall friction were 55° and 31.4° for sawdust; 36.2° and 26° for brown coal; and 43.3° and 27.8° for hard coal. Using the measured powder flow properties, Jenike's procedure was then followed to estimate and compare the critical hopper dimensions for mass flow of the three powders.