磺化法净化中丙酮对β、δ六六六的影响与消除

磺化法净化六六六提取液时，残留在石油醚相中的丙酮引起β、δ六六六两组分部分损失。本文研究了丙酮残留量与β、δ六六六两组分磺化损失间的关系，实测了常规条件下丙酮的残留量，找出用2％NaSO4溶液两次洗涤提取液，有效降低丙酮残留量，减少β、δ六六六组分磺化的简便方法，用于土壤样品测定获得满意结果。     

浅谈气象测湿用毛发的处理方法

作为湿度感应元件的毛发,在使用过程中会由于污染、拉伸等原因而影响湿度的测量精度,因此在一般情况下至少要一年进行一次清冼和调整,重新检定受到损伤的毛发要重新更换,以保证仪器的准确度不受影响。     

Study on changes in bed characteristics and friction factor in the presence of wash load in suspension

Results of an experimental study on the effects of different concentrations of wash load on the size of bed features and resistance to flow in a laboratory flume are presented. The experiments were carried out under different hydraulic conditions in a 30 m long, 0.204 m wide and 0.5 m deep tilting flume under clear water condition and in the presence of different concentration of wash load in the flow. The bed material used consisted of uniform sediment of size 0.96 mm. Analysis of the data indicates that the characteristics of the bed features change and friction factor increases in the presence of different concentration of wash load in the flow. The reasons for changes in the characteristics of the bed features and increase in friction factor in the presence of wash load are identified and a relationship for predicting friction factor in the presence of wash load has been established.     

美国国家公园掠影

美国人认为自然的美丽、宏伟和辽阔可洗涤人的灵魂、陶冶人的情操。他们崇尚野生的没有经过人工雕刻的自然。而美国西部奇特的地理地貌自然奇观,使他们把自己自然至上的理念得以完美诠释     

洗涤条件的选择及其对人发AAS测定的影响

介绍了人发洗涤的最佳条件，加标回收率为９０－１０５％，ＲＳＤ为０．６８－５．８５％。用于人发中微量元素ＡＡＳ测定，结果满意。     

专家认为：杀菌皂与普通肥皂没区别

美国食品和药物管理局（FDA）的一个专家小组最近提出，杀菌皂的洗手和洗涤效果与使用普通肥皂是一样的。     

Study of polluted soil remediation based on freezing and thawing cycles

It is generally known that soil pollution poses a terrible hazard to the environment, but the present techniques of contaminated soil remediation cannot control this growing threat. This paper compares the pollutant extraction efficiency of traditional pumping and treating, which is a typical washing technology for the remediation of contaminated soils, with methods that utilize freeze-thaw cycles. In the soil freezing process, water shifts from unfrozen soils to the freezing front, and the permeability of soil will be enhanced under certain temperature gradients and water conditions. Therefore, this paper discusses the purification of contaminated soil through freeze-thaw action. We conducted a cleansing experiment on clay and silica sand infused with NaCl（simulation of heavy metals） and found that the efficiency of purification was enhanced remarkably in the latter by the freeze-thaw action. To assess the effective extraction of DNAPLs in soil, we conducted an experiment on suction by freezing, predicated on the different freezing points of moisture and pollutants. We found that the permeability coefficient was significantly increased by the freezing-thawing action, enabling the DNAPL contaminants to be extracted selectively and effectively.     

海运船舶尾气洗涤废水中多环芳烃对海洋污染的研究现状及展望

分析了海运船舶尾气洗涤废水排放对多环芳烃 (PAHs) 类污染物的海洋富集行为的影响以及对 PAHs 控制的制约因 素和净化技术发展现状。PAHs 的海洋富集趋势与船舶的发动机尾气排放行为呈正相关性, 且船舶尾气洗涤废水排放加速了 PAHs 向海洋中富集。 国际海事组织 (IM0) 尚未对在PAHs 中占比大且毒性强的烷基化多环芳烃进行立法限制, 但单方面采 取措施禁止船舶尾气洗涤废水在其所属海域排放的国家和地区日益增多, 洗涤废水排放的PAHs 类污染物亟须净化处理。将 高级氧化光催化技术应用于洗涤废水排放的PAHs 净化具有发展前景。我国应抓住机遇, 大力开展针对海洋 PAHs 的排放限 制立法以及船舶尾气洗涤废水处理先进技术的研究, 这对于提升我国海事管理水平、增大国际话语权, 以及保护海洋生态安 全具有重要意义。     

毛发试样的干法预处理

有关毛发中微量元素的测定，已有很多报道^[1]，但就其洗涤和前处理的方法问题，怎样更合理，更符合快速准确的分析原则，我们认为有必要进一步探讨。本文就我中心在1990年元月初前所用湿法和改进后的干法简述加以比较。