【摘 要】
:
The rapid development of rainwater harvesting technology, has led to renewed interest in improving catchment surface performance, as the first link in the rainwater harvesting system.Research is focus
【机 构】
:
Gansu Research Institute for Water Conservancy, Larzhou, China 730000
论文部分内容阅读
The rapid development of rainwater harvesting technology, has led to renewed interest in improving catchment surface performance, as the first link in the rainwater harvesting system.Research is focused on the development of new types of impermeable catchment materials which are low-cost, have high collection efficiency and yield pollution-free water.The proposed modified concrete mixtures should be further studied and undergo rigorous field testing.The results of this study showed that: (1)Polypropylene fibers are ideal for concrete admixtures, as these can enhance the strength of catchments areas, improve the concrete performance, strength grade, and frost resistance; (2) to reduce costs of catchment surface construction, the ideal thickness is 3.0 cm, as this provides the required bearing strength and frost resistance as well as ensuring a high runoff coefficient; (3) the two best options for concrete Catchment Surface Area materials are, C15 + polypropylene fibers and C20 concrete.These concrete types compare favorably with conventional concrete catchments and their widespread application is recommended in the future.
其他文献
以纳米c-ZrO2为载体,用浸渍法制备出MnOx-CeO2/c-ZrO2催化剂,考察活性组分负载量、反应温度对催化剂N-H3-SCR脱硝活性影响,探讨催化剂表面织构特征,分析催化剂脱硝活性机理.结果显示,增加活性组分负载量和反应温度,催化剂脱硝效率增加,100℃时,2.5%MNOx-CeO2/c-ZrO2脱硝效率为65.3%,15%MnOx-CeO2/c-ZrO2脱硝效率达97.9%.XRD,BE
壳聚糖水凝胶由于具有优异的生物相容性、生物可降解性和生物活性等,被广泛地应用于药物载体、组织工程支架生物医学领域.纳米石墨具有优异的电学、热学和力学性能,在电子、能源、医药等领域得到广泛应用.将纳米石墨和Fe3O4纳米颗粒引入壳聚糖体系,赋予其优异的导电导热和磁场相应特性.
脊柱的退行性病变是临床常见的疾病,椎间融合是临床常用的治疗方法.在椎间融合手术中,通常使用椎间融合器进行植骨融合.目前常见的椎间融合器材料包括不锈钢、钛合金、聚醚醚酮、碳纤维等,这些材料存在弹性模量过高、生物相容性不佳,骨整合能力差等各个方面的不足,尚不能很好地满足临床上对椎间融合材料的要求.
形状记忆聚氨酯(SMPU)是一类新型的热致形状记忆高分子材料,其原料选择范围宽,配方可调控性大,机械性能和形状记忆功能优异,能够满足多种场合的使用要求,具有较高的潜在应用价值.本论文选用具有良好生物相容性的聚ε-己内酯(PCL)作为软段,异氟尔酮二异氰酸酯(IPDI)作为硬段,1,4-丁二醇(BDO)作扩链剂,通过聚加成法制备出聚氨酯(PU)形状记忆材料.进一步以N,N-二甲基甲酰胺(DMF)为溶
Tungsten oxide is well known for its wide applications such as photocatalyts, gas sensors, electrochromic coatings and microelectronic devices.
本文采用湿化学法以Cdcl2为原料,以水合肼为还原剂,通过制备出不同粒径的Cd前驱物,进而注入二氧化硒的溶液将前驱物硒化,同时以高分子PVP(聚乙烯吡咯烷酮)等其他修饰剂为修饰剂合成得到了不同粒径大小的Cdse纳米粒子,同时对应向CdSe粒径大小的因素进行了初步探索,并且对不同粒径大小的Cdse纳米粒子的紫外吸收和荧光发射波长进行了分析研究.研究结果表明当Se与Cd的摩尔比例从0.8∶1变为1∶1
采用有机前驱体热解法制备了半直立的带金属头的碳化硅纳米线阵列.采用XRD、SEM、TEM等对带金属头的碳化硅纳米线进行了系统的分析与表征.结果表明:碳化硅纳米线的直径为几百纳米,长度为几~十几个微米的单晶结构,生长方向为[111].并对带金属头的碳化硅纳米线阵列的场发射性能进行了研究,结果表明其具有较好的场致电子发射的能力.
In order to improve the tunnel bend and the downstream flow regime, a measure of cover plate has been adopted in the gate-type spillway tunnel.The improvement effect of the measure is not only related
The large quality of natural stone is more difficult to obtain in river closure project, and is replaced by concrete tetrahedrons and other artificial prefabricated materials.The method was proposed t
In recent years, a number of earth dams reached or will reach the end of their design life.The possibility of dam-break is increasing under the continuous erosion due to flood overtopping.However,beca