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Xuzhou city lies on the north of Jiangsu province. Its geological conditions are complex, water resources are deficient and environment is vulnerable. At present, water pollution in Kui river area is very serious, the water movement and heat transfer characteristics of unsaturated zone in Kui river area was studied to provide a theory foundation for predicting pollution of unsaturated zone removing and transforming. The study was considered through the rule of energy flow and nutrient cycling under different vegetation cover: temperature of soil decreases with increasing depths in most area, but different vegetation cover causes vary between variation-rate in different temperature, which some vegetation cover cause temperature of soil increases with increasing depths.

Xuzhou city lies on the north of Jiangsu province, which geological conditions are complex, water resources are deficient and environment is vulnerable. At present, water pollution in Kui river area is very serious; Kui River nitrogen pollution had affected Coastal soil and chemical environment of groundwater. The monitoring sections are elected in the seriously polluted river, and downstream at the banks of river decorates with six monitoring sections. Each section from the river bank of 50m, 100m, 200m, 500m, 1000m, 1500m is arranged of monitoring points respectively, and each monitoring point is monitored for sampling test at different depths. The monitoring results of surface water showed that the content of ammonia-nitrite-nitrate was a decreasing trend along the flow direction. The nitrate nitrogen content would decrease further in December while the ammonium nitrogen content was on the rise, showing that the supplement of nitrogen pollution resources was still insufficient when the denitrification was stronger. The content of ammonium and nitrate nitrogen in soil was higher, and had some regular change features with the change of depth.

This paper presents a novel method to reduce the inrush currents produced by interconnecting induction generators. The method is based on the sequential energization of the contactors and a grounding resistor connected at the neutral point of a wye-connected stator. Analytical developments are presented, which permit to determine the optimum value of the neutral resistor directly. Theoretical and simulation analysis show that the proposed method can be almost as effective as the traditional three series resistor method. The proposed method requires only one resistor and one bypass contactor and is therefore more cost-effective than the traditional methods.