原地聚合制备高强度凝胶及其封堵性能研究

本文以丙烯酰胺、甲基丙烯酸钠为单体,过硫酸铵为引发剂,铁氰化钾为速率控制剂,采用原地聚合法,成功制备出了高强度凝胶堵剂。通过正交实验,对体系配方进行了优化,测试了所制备的高强度凝胶的膨胀性能和封堵性能。实验结果显示,将铁氰化钾为0.04%、过硫酸钾为0.15%、甲基丙烯酸钠为3.0%、丙烯酰胺为8.0%、N,N’-亚甲基双丙烯酰胺为0.15%、体系pH值为6的溶液装入砂管,在70℃下原地聚合10h后,形成的高强度凝胶对填砂管的封堵率达99.87%以上,突破压力大于18.3MPa·m^(-1)。

Contamination of Groundwater Sources with Common Waterborne Pathogens and Heficobacter pylori in the West Bank： Case Study of Wadi AI Arroub, Tulkarem and Jericho

Detection of waterborne pathogens in drinking water via rapid DNA amplification assays is an important and crucial public health method. The aim of this study is to investigate the presence of waterborne pathogens in groundwater resources in Al Arroub, Tulkarem and Jericho areas using direct PCR （polymerase chain reaction） analysis. Forty-six groundwater samples were collected. The total DNA was extracted from each sample and subjected to PCR analysis directed to specific genes of enteric bacteria, β-lactamases producing bacteria, L. pneumophila （Legionella pneumophila） and H. pylori （Helicobacter pylori）. Enteric bacteria were detected with high frequency in Palestinian water sources followed by 13% occurrence of β-lactamases producing bacteria, 9% of H. pylori and 4% of L. pneumophila. The study shows that shallow groundwater wells and water taped from karstic aquifer is potential for contamination and could not be reliable sources of potable water.