EN—1对砒砂岩固化土坡面径流水动力学特征的影响

为探讨砒砂岩地区工程边坡径流的侵蚀规律,通过室内模拟冲刷试验,对添加EN-1固化剂后不同固化剂掺量、养护龄期和压实度的边坡径流水动力学特征进行了研究.结果表明:在试验设计的固化剂掺量、养护龄期和压实度处理条件下,砒砂岩固化土坡面径流流速随固化剂掺量、养护龄期和压实度的增大而增大,且径流流速随冲刷的进行呈现出波动减小的趋势.径流雷诺数Re随固化剂掺量、养护龄期和压实度的增大而减小,且Re有随冲刷的进行而逐渐增大的波动变化趋势,而弗劳德数Fr的变化趋势正好与Re相反.除压实度在较小处理冲刷后期时径流流态为紊流和缓流外,其他处理都是层流和急流.径流Darcy - Weisbach阻力系数f随固化剂掺量、养护龄期和压实度增大而减小,且f与输沙率有一定的正相关关系.     

Water quality and sludge characterization at raceway-system trout farms

Studies were conducted to characterize raceway water quality, effluent water quality, and waste solids within three, raceway-type trout farms. No significant differences were found in effluent water quality between the three farms during 7 months of monitoring. Average effluent quality over the course of the day was not found to be impaired. However, effluent quality was found to change significantly during times of feeding and harvesting. In a concrete/earthen-lined farm, normalized total suspended solids (TSS) concentrations were as high as 115 and 63 mg/l during harvesting and feeding events, respectively. Total Kjeldahl nitrogen (TKN) and ortho-phosphate (OP) also increased with higher TSS loads. The majority of particles (by weight) measured in effluent samples at all three farms were evenly divided between the smallest range (1.5–30 μm) and the largest (>210 μm). For settled sludge samples, the majority of the particles were in the size range of 1.5–30 μm. Particle size in the raceway was positively correlated with fish size during feeding events, but this correlation dissipated during the 4-h period after feeding. The accumulation and characteristics of sludge in a sediment trap were also monitored over a 22-day period.     

天山北坡水库泥沙淤积情势分析──以头屯河水库为例

本文着重讨论了头屯河水库泥沙淤积问题，详细分析了头屯河入库水沙特性和水库泥沙淤积的原因及影响因素，运用灰色动态模型对水库泥沙淤积的趋势进行预测，指出水库排沙减淤的可能性．为恢复水库库容提供理论依据。     

岷江干旱河谷区不同土地利用方式下土壤抗冲性试验

采用野外实地放水冲刷的试验方法,对岷江上游干旱河谷区龙坝沟流域不同土地利用方式(灌木林地、荒草地、耕地和裸地)下土壤抗冲性进行测试研究,分析了土壤侵蚀产沙相关因素。结果表明:不同土地利用方式下土壤抗冲系数均随冲刷时间延长呈波状上升变化趋势;土壤的抗冲性从大到小依次为:荒草地、小麦耕地、灌木林地、玉米耕地、裸地;土壤抗冲系数与粉粒体积分数呈显著负相关(相关系数为-0.992,P<0.01),与砂粒体积分数呈显著正相关(相关系数为0.925,P<0.01)。     

A study on dehairing Australian greasy cashmere

Cashmere is a luxury fiber with high international demand. Australian cashmere fleece is shorn rather than hand combed, and the shorn fleece contains a large quantity of coarse guard hair. Normally raw cashmere fleece is scoured first, followed by dehairing to eliminate the coarse guard hair. But scouring the unwanted guard hair consumes a large quantity of water, and increases the cost of cashmere processing in Australia. Ideally, the guard hair should be removed first and then the fine cashmere fibers are scoured for further processing. This paper reports trial results on dehairing greasy rather than scoured Australian cashmere fleece, with the aim of reducing scouring cost and water consumption. The quality of cashmere fibers after the conventional dehairing process and the new greasy dehairing process has been assessed. The results indicate that fiber quality from the greasy dehairing process is better than that from conventional scouring then dehairing process.