事故出流时河流综合水质的计算机预测方法研究

河流上游的污水排放口或倒虹管等污水构筑因有可能发生事故出流而对下游的取水口存在着潜在的威胁，常规的单参数模型不能就事故出流对下游的影响作出公正评价。本文以QUAL－Ⅱ模型为骨架，以生动形象的动画形式演示出在整个排污过程中多个水质参数沿河道分布的变化全过程，并且，在模型中融入隶属度BP神经网络综合评价水质的模块，用它来对发生事故出流时下游取水口水域的水质变化进行综合评价，最后通过一个例子说明了该方法的优越性和合理性。     

Synaptic plasticity

Synaptic plasticity is manifested by long-lasting changes in synaptic potency. Increased potency is of special importance in relation to the neural basis of memory. Even mild repetitive stimulation evokes large and prolonged potentiations of hippocampal synapses, as is revealed by electrical recording either in vivo or in vitro. More importantly there is a matching hypertrophy of the synaptic spines on the dendrites of hippocampal granule cells, as is shown by most convincing electronmicrographs. The increase is to about 40% some 2 h after a mild stimulation (900 impulses) and there was relatively little decline by 23 h. There is brief reference to the metabolic processes that could be involved in this plastic response.     

于桥水库流域暴雨径流中锰的输送特征及其对水库水质的影响

对于桥水库流域内暴雨径流中锰含量形态的研究表明,锰主要以悬浮状态存在,其中易释放的、潜在释放的和非释放形态的锰所占比例分别为10％、60％和30％.以溶解态迁移的锰极少.流域内的锰矿-含锰页岩带提高了暴雨径流中总锰的浓度,对于桥水库水质造成了一定的影响.