全再生细骨料(Complete Recycled Fine Aggregate)是废弃混凝土利用的新方法,其表观密度和吸水性能明显优于传统再生细骨料。采用全再生细骨料替代河砂制备了免蒸压陶粒轻质混凝土及隔墙板试件,测试了所制备材料的面密度、抗压强度和干...全再生细骨料(Complete Recycled Fine Aggregate)是废弃混凝土利用的新方法,其表观密度和吸水性能明显优于传统再生细骨料。采用全再生细骨料替代河砂制备了免蒸压陶粒轻质混凝土及隔墙板试件,测试了所制备材料的面密度、抗压强度和干缩率。实验结果表明:优选的全再生细骨料免蒸压陶粒轻质混凝土配合比为水胶比为0.30,砂胶比为2.0,陶粒绝对体积掺量为15%,混凝土目标湿密度为1650 kg/m^3;在面密度相同时,与使用河砂的免蒸压陶粒轻质混凝土隔墙板相比,全再生细骨料免蒸压陶粒轻质混凝土隔墙板抗压强度略高,干缩值较大,其较高的干缩值可能是其含水率较高和实验前浸泡饱水所致,可通过延长养护时间至7 d解决;使用引气方式制备的全再生细骨料免蒸压陶粒轻质混凝土隔墙板的面密度、抗压强度和干缩率均能满足JG/T 169—2016《建筑隔墙板用轻质条板通用技术要求》标准要求,与现有的蒸压陶粒轻质混凝土隔墙板相比,其混凝土材料成本可降低23%;采用全再生细骨料制备免蒸压陶粒轻质混凝土隔墙板是促进废弃混凝土再生利用和隔墙板绿色生产的有效途径。展开更多
Nanofiber has been widely used in numerous fields for its good advantages such as large surface area and porosity.However,the relationship between nanofiber structure and coaxial electrospinning process is still not c...Nanofiber has been widely used in numerous fields for its good advantages such as large surface area and porosity.However,the relationship between nanofiber structure and coaxial electrospinning process is still not clear and deserved to be studied.In this work,a kind of polyurethane/nickel(PU/Ni)nanofiber with core-shell structures was developed,and the effects of electrospinning parameters on the properties of nanofiber were evaluated.The results showed that the optimized parameters of core-shell electrospinning speeds were 1 mL/h(core)and 1 mL/h(shell),respectively.Sample c with the core-shell electrospinning speed ratio of 1∶1,exhibited the relatively smooth surface,good orientation,and bonding points.It also had the largest tensile strength at 99 cN,tensile elongation at 44.86%,and the best electricity conductivity,which showed great potential in the application of nanofiber fields.展开更多
文摘Nanofiber has been widely used in numerous fields for its good advantages such as large surface area and porosity.However,the relationship between nanofiber structure and coaxial electrospinning process is still not clear and deserved to be studied.In this work,a kind of polyurethane/nickel(PU/Ni)nanofiber with core-shell structures was developed,and the effects of electrospinning parameters on the properties of nanofiber were evaluated.The results showed that the optimized parameters of core-shell electrospinning speeds were 1 mL/h(core)and 1 mL/h(shell),respectively.Sample c with the core-shell electrospinning speed ratio of 1∶1,exhibited the relatively smooth surface,good orientation,and bonding points.It also had the largest tensile strength at 99 cN,tensile elongation at 44.86%,and the best electricity conductivity,which showed great potential in the application of nanofiber fields.
