To investigate the influences of different admixtures on the drying shrinkage of polymer mortar in a metakaolin base,the experiments of VAE(vinyl acetate ethylene copolymer),APAM(anionic polyacrylamide)and CPAM(cation...To investigate the influences of different admixtures on the drying shrinkage of polymer mortar in a metakaolin base,the experiments of VAE(vinyl acetate ethylene copolymer),APAM(anionic polyacrylamide)and CPAM(cationic polyacrylamide)on the drying shrinkage properties of geopolymer mortar were designed under normal temperature curing conditions.An SP-175 mortar shrinkage dilatometer was introduced to measure the dry shrinkage of geopolymer mortar.Meanwhile,the drying shrinkage properties of geopolymer mortar are exhibited by the parameters of water loss rate,drying shrinkage rate,drying shrinkage strain and drying shrinkage coefficient.The experimental data are further fitted to obtain the prediction model of dry shrinkage of geopolymer mortar,which can better reflect the relationship between dry shrinkage rate and time.Finally,the experimental results demonstrate that the dry shrinkage of geopolymer mortar can be significantly increased by adding 4%VAE admixture,meanwhile under the condition that the polymer film formed by VAE reaction can strengthen and toughen the mortar.2.5%APAM admixture and 1.5%CPAM admixture can enhance the dry shrinkage performance of geopolymer mortar in a certain range.展开更多
电容式电压互感器是电力系统中重要的保护和计量设备,其可靠运行对电网的安全稳定有着重要影响。本文针对一起500kV电容式电压互感器(Capacitive Voltage Transformer,CVT)介质损耗因数与电容量偏大的异常情况进行了详细分析,通过电气...电容式电压互感器是电力系统中重要的保护和计量设备,其可靠运行对电网的安全稳定有着重要影响。本文针对一起500kV电容式电压互感器(Capacitive Voltage Transformer,CVT)介质损耗因数与电容量偏大的异常情况进行了详细分析,通过电气试验、数据计算及解体分析有效判断设备的故障类型和故障点,有效避免了事故发生,保障了电网安全。展开更多
基金Funded by the the Shaanxi Provincial Natural Science Basic Research Plan(No.2021JQ-471)the Natural Science Project of Shaanxi Provincial Department of Education(No.21JK0802)。
文摘To investigate the influences of different admixtures on the drying shrinkage of polymer mortar in a metakaolin base,the experiments of VAE(vinyl acetate ethylene copolymer),APAM(anionic polyacrylamide)and CPAM(cationic polyacrylamide)on the drying shrinkage properties of geopolymer mortar were designed under normal temperature curing conditions.An SP-175 mortar shrinkage dilatometer was introduced to measure the dry shrinkage of geopolymer mortar.Meanwhile,the drying shrinkage properties of geopolymer mortar are exhibited by the parameters of water loss rate,drying shrinkage rate,drying shrinkage strain and drying shrinkage coefficient.The experimental data are further fitted to obtain the prediction model of dry shrinkage of geopolymer mortar,which can better reflect the relationship between dry shrinkage rate and time.Finally,the experimental results demonstrate that the dry shrinkage of geopolymer mortar can be significantly increased by adding 4%VAE admixture,meanwhile under the condition that the polymer film formed by VAE reaction can strengthen and toughen the mortar.2.5%APAM admixture and 1.5%CPAM admixture can enhance the dry shrinkage performance of geopolymer mortar in a certain range.
文摘电容式电压互感器是电力系统中重要的保护和计量设备,其可靠运行对电网的安全稳定有着重要影响。本文针对一起500kV电容式电压互感器(Capacitive Voltage Transformer,CVT)介质损耗因数与电容量偏大的异常情况进行了详细分析,通过电气试验、数据计算及解体分析有效判断设备的故障类型和故障点,有效避免了事故发生,保障了电网安全。
