Precipitation chemistry analysis is essential to evaluate the atmospheric environmental quality and identify the sources of atmospheric pollutants. In this study, we collected a total of 480 precipitation samples at 6...Precipitation chemistry analysis is essential to evaluate the atmospheric environmental quality and identify the sources of atmospheric pollutants. In this study, we collected a total of 480 precipitation samples at 6 sampling sites in the northern and southern slopes of Wushaoling Mountain from May 2013 to July 2014 to analyze the chemical characteristics of precipitation and to identify the main sources of ions in precipitation. Furthermore, we also explored the indicative significance for sand dust events in the northern and southern slopes of Wushaoling Mountain based on the precipitation chemistry analysis.During the sampling period(from May 2013 to July 2014), the p H values, EC(electrical conductivity)values and concentrations of cations(Ca^(2+), Mg^(2+), Na~+, K~+ and NH_4~+) and anions(SO_4^(2–), NO_3~–, Cl~–, NO_2~– and F~–) in precipitation were different in the northern and southern slopes at daily and seasonal time scales, with most of the values being higher in the northern slope than in the southern slope. The chemical type of precipitation in the southern and northern slopes was the same, i.e.,SO_4^(2–)-Ca^(2+)-NO_3~–-Na~+. The concentrations of ions in precipitation were mainly controlled by terrigenous material and anthropogenic activities(with an exception of Cl~–). The concentration of Cl~– in precipitation was mainly controlled by the sea salt fraction. The concentrations of Na+ and Cl~– showed an increasing trend after the occurrence of sand dust events both in the northern and southern slopes. In addition, after the occurrence of sand dust events, the concentrations of K~+, Mg^(2+), SO_4^(2–), NO_3~– and Ca^(2+) showed an increasing trend in the southern slope and a decreasing trend in the northern slope. It is our hope that the results may be helpful to further understand the atmospheric pollution caused by sand dust events in the Wushaoling Mountain and can also provide a scientific basis for the effective prevention of atmospheric pollution.展开更多
猪链球菌(Streptococcus suis,SS)是一种重要的人畜共患病原体,猪链球菌2型(Streptococcus suis type 2,SS2)1954年首次在英国分离鉴定,在我国和其他养猪业发达的国家已多次流行,已成为危害我国养猪业和公共卫生安全的一个重要传染病。...猪链球菌(Streptococcus suis,SS)是一种重要的人畜共患病原体,猪链球菌2型(Streptococcus suis type 2,SS2)1954年首次在英国分离鉴定,在我国和其他养猪业发达的国家已多次流行,已成为危害我国养猪业和公共卫生安全的一个重要传染病。本研究用SS2-ZY05719株按10^(9)、10^(8)、10^(6)CFU腹腔注射途径人工感染健康的新西兰兔,3种剂量均可引起发病并死亡,新西兰兔临床症状明显,感染组平均体温升高1℃~2℃。同时分析了SS2在兔体各组织中的分布,结果显示,高剂量感染组出现明显的临床症状且快速死亡,感染剂量与发病程度有正相关性,对各试验组新西兰兔内脏组织进行检测发现,SS2主要集中在心脏、肝脏、脾脏、肺脏、肾脏和脑等组织中,不同组织器官中的细菌载量也存在着一定的差异,本文研究了SS2感染新西兰兔后的临床症状和各组织载菌量,为猪链球菌的防治及致病机理研究提供参考。展开更多
基金supported by the Gansu Province Science Fund for Distinguished Young Scholars (1506RJDA282)the National Natural Science Foundation of China (41271039, 91547102)+2 种基金the Open Foundation of MOE Key Laboratory of Western China’s Environmental System of Lanzhou Universitythe Open Foundation from State Key Laboratory (SKLFSE201403)the West Light Program for Talent Cultivation of Chinese Academy of Sciences
文摘Precipitation chemistry analysis is essential to evaluate the atmospheric environmental quality and identify the sources of atmospheric pollutants. In this study, we collected a total of 480 precipitation samples at 6 sampling sites in the northern and southern slopes of Wushaoling Mountain from May 2013 to July 2014 to analyze the chemical characteristics of precipitation and to identify the main sources of ions in precipitation. Furthermore, we also explored the indicative significance for sand dust events in the northern and southern slopes of Wushaoling Mountain based on the precipitation chemistry analysis.During the sampling period(from May 2013 to July 2014), the p H values, EC(electrical conductivity)values and concentrations of cations(Ca^(2+), Mg^(2+), Na~+, K~+ and NH_4~+) and anions(SO_4^(2–), NO_3~–, Cl~–, NO_2~– and F~–) in precipitation were different in the northern and southern slopes at daily and seasonal time scales, with most of the values being higher in the northern slope than in the southern slope. The chemical type of precipitation in the southern and northern slopes was the same, i.e.,SO_4^(2–)-Ca^(2+)-NO_3~–-Na~+. The concentrations of ions in precipitation were mainly controlled by terrigenous material and anthropogenic activities(with an exception of Cl~–). The concentration of Cl~– in precipitation was mainly controlled by the sea salt fraction. The concentrations of Na+ and Cl~– showed an increasing trend after the occurrence of sand dust events both in the northern and southern slopes. In addition, after the occurrence of sand dust events, the concentrations of K~+, Mg^(2+), SO_4^(2–), NO_3~– and Ca^(2+) showed an increasing trend in the southern slope and a decreasing trend in the northern slope. It is our hope that the results may be helpful to further understand the atmospheric pollution caused by sand dust events in the Wushaoling Mountain and can also provide a scientific basis for the effective prevention of atmospheric pollution.
文摘猪链球菌(Streptococcus suis,SS)是一种重要的人畜共患病原体,猪链球菌2型(Streptococcus suis type 2,SS2)1954年首次在英国分离鉴定,在我国和其他养猪业发达的国家已多次流行,已成为危害我国养猪业和公共卫生安全的一个重要传染病。本研究用SS2-ZY05719株按10^(9)、10^(8)、10^(6)CFU腹腔注射途径人工感染健康的新西兰兔,3种剂量均可引起发病并死亡,新西兰兔临床症状明显,感染组平均体温升高1℃~2℃。同时分析了SS2在兔体各组织中的分布,结果显示,高剂量感染组出现明显的临床症状且快速死亡,感染剂量与发病程度有正相关性,对各试验组新西兰兔内脏组织进行检测发现,SS2主要集中在心脏、肝脏、脾脏、肺脏、肾脏和脑等组织中,不同组织器官中的细菌载量也存在着一定的差异,本文研究了SS2感染新西兰兔后的临床症状和各组织载菌量,为猪链球菌的防治及致病机理研究提供参考。