鉴于冻融破坏是影响我国北方地区混凝土耐久性的主要原因,利用Rapid Air 457硬化混凝土气孔结构分析仪(丹麦CXI)对高性能混凝土中孔结构进行可视化表征和定量计算,得到平均孔径大小、气泡间距系数及孔径分布情况,进而表征混凝土抗冻性...鉴于冻融破坏是影响我国北方地区混凝土耐久性的主要原因,利用Rapid Air 457硬化混凝土气孔结构分析仪(丹麦CXI)对高性能混凝土中孔结构进行可视化表征和定量计算,得到平均孔径大小、气泡间距系数及孔径分布情况,进而表征混凝土抗冻性能。研究表明:除混凝土含气量外,气泡间距系数、d≤100μm孔含量都是表征混凝土抗冻性能的重要指标。展开更多
A series of granular activated carbons （GACs） were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET speci...A series of granular activated carbons （GACs） were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET specific surface area （SBEr）, total pore volume （Vr） and average pore diameter （da） were measured and cal- culated as well as process parameters such as yield of char （CY） and burn-off （B）. The relationship between the pore structural parameters of the GAC from coal blend （BC-GAC） and the ones of the GACs from corresponding single coals （SC-GACs） was analyzed, in which an index, the relative error （δ）, was presented to define the bias between fitted values and experimental values of these parameters of the BC-GACs. The results show that the BC-GAC keeps qualitatively the pore structural features of the SC-GACs; as concerned as the quantitative relationship, the pore structural parameters of the BC-GAC from coal blend consisting of non-caking coals can be obtained by adding proportionally the pore structural parameters of the SC-GACs with a less than 10%. Meanwhile, for the BC-GAC from coal blend containing weak caking bituminous coal, the δ increases up to 25% and the experimental pore size distribution differs greatly from the fitted one.展开更多
文摘鉴于冻融破坏是影响我国北方地区混凝土耐久性的主要原因,利用Rapid Air 457硬化混凝土气孔结构分析仪(丹麦CXI)对高性能混凝土中孔结构进行可视化表征和定量计算,得到平均孔径大小、气泡间距系数及孔径分布情况,进而表征混凝土抗冻性能。研究表明:除混凝土含气量外,气泡间距系数、d≤100μm孔含量都是表征混凝土抗冻性能的重要指标。
基金financially supported by the National High-Tech Research and Development Program of China (No.2008AA05Z308)the National Natural Science Foundation of China (No.20776150)
文摘A series of granular activated carbons （GACs） were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET specific surface area （SBEr）, total pore volume （Vr） and average pore diameter （da） were measured and cal- culated as well as process parameters such as yield of char （CY） and burn-off （B）. The relationship between the pore structural parameters of the GAC from coal blend （BC-GAC） and the ones of the GACs from corresponding single coals （SC-GACs） was analyzed, in which an index, the relative error （δ）, was presented to define the bias between fitted values and experimental values of these parameters of the BC-GACs. The results show that the BC-GAC keeps qualitatively the pore structural features of the SC-GACs; as concerned as the quantitative relationship, the pore structural parameters of the BC-GAC from coal blend consisting of non-caking coals can be obtained by adding proportionally the pore structural parameters of the SC-GACs with a less than 10%. Meanwhile, for the BC-GAC from coal blend containing weak caking bituminous coal, the δ increases up to 25% and the experimental pore size distribution differs greatly from the fitted one.
