纳米技术的风险管理与对策

阐述纳米材料与纳米技术可能导致的环境与健康的不确定风险以及实施安全性评价的必要性.在推动纳米科技和纳米产品研发的同时,应秉持科技进步有益于社会整体发展的原则,针对这些技术可能引起的健康、安全、环境、伦理和社会的隐含问题和不确定性,开展纳米产品及与纳米相关的法律、环境与健康潜在风险研究,制定相关安全性评价和风险管理规范以应对潜在的释放风险.     

全氟异丁烯的毒性和检测防护技术

本文介绍了全氟异丁烯(PFIB)物化性质及产生;总结了其毒性;分析了气相色谱法分析PFIB方法:讨论了人员和环境防护技术.     

糖蜜酒精废水两相UASB处理工艺的酸化段特征

文章考察了糖蜜酒精废水二相UASB处理工艺的酸化段特征 ,试验结果表明酸化段的容积负荷达到3 0kgCOD/m3 时 ,系统仍能正常运行 ,TOC去除率在 3 5%以上 ,酸化段的SO4 2 -去除率在 70 %。糖蜜酒精废水酸化率在 50 % ,二相厌氧生物处理系统并未将产酸微生物与产甲烷微生物截然分开 ,在产酸相中仍含有一定数量的产甲烷菌。     

云南蒋家沟泥石流运动特征及其发展趋势

根据蒋家沟1965~2005年的泥石流运动观测资料与会泽气象站1965~2005年日降水资料,应用Hurst指数分析泥石流的运动要素,研究发现:泥石流年输沙量的Hurst指数为0.682时,年输沙量呈较强的正持续性,未来呈增长趋势;降雨量的Hurst指数0.605时,降雨量呈较弱的正持续性,未来呈较弱的增长趋势。同时,运用小波分析方法,发现泥石流输沙量具有多时间尺度周期的特征,主要表现为:第8、14和24年分别为其第1、2和3活动周期;结合小波方差图分析可知:在未来15 a以上,年输沙量将呈减少趋势,泥石流活跃程度弱;而15 a以内,未来将会保持较短时间的增加趋势,泥石流活跃程度强。综合以上分析可知:蒋家沟泥石流具有规模巨大,作用强烈,类型齐全等主要特征。     

乌江流域石灰土中铀等元素形态与铀活性

以中国西南乌江流域石灰土为例,运用逐级提取(Sequential Extraction,SEE)技术,并结合化学成分和相关参数数据,研究了石灰土中铀(U)等元素的形态,并在此基础上探讨了石灰土中U的活动性及释放潜力,旨在增进对U等元素生物地球化学循环的了解,同时也为流域U污染防治提供科学依据。研究结果表明：①石灰土中Mn主要存在于锰(氢)氧化物中,Ca主要存在于碳酸盐和硅酸盐矿物中,P主要存在于硅酸盐矿物和有机质中,U主要赋存于硅酸盐等残留部分中,其次赋存于有机质结合部分和碳酸盐矿物中;②石灰土剖面中活动态U所占的比例为10%~30%,平均17%,说明石灰土中的部分U在酸性和氧化-还原界面等条件下具有一定的迁移活性,即在上述条件下,石灰土中的部分U可释放进入周围水体或植物中;③石灰土中U的潜在释放量为036~150 g/t,平均U潜在释放量为076 g/t,因此,在酸雨和侵蚀等作用下,石灰土U释放可显著提高乌江河水U通量。     

Effect of copper on the degradation of pesticides cypermethrin and cyhalothrin

The influence of coexisting copper (Cu) ion on the degradation of pesticides pyrethroid cypermethrin and cyhalothrin in soil and photodegradation in water system were studied.Serial concentrations of the pesticides with the addition of copper ion were spiked in the soil and incubated for a regular period of time,the analysis of the extracts from the soil was carried out using gas chromatography (GC).The photodegradation of pyrethroids in water system was conducted under UV irradiation.The effect of Cu~(2 ) on the pesticides degradation was measured with half life (t_(0.5)) of degradation.It was found that a negative correlation between the degradation of the pyrethroid pesticides in soil and Cu addition was observed.But Cu~(2 ) could accelerate photodegradation of the pyrethroids in water.The t_(0.5) for cyhalothrin extended from 6.7 to 6.8 d while for cypermethrin extended from 8.1 to 10.9 d with the presence of copper ion in soil.As for photodegradation,t_(0.5) for cyhalothrin reduced from 173.3 to 115.5 rain and for cypermethrin from 115.5 to 99.0 min.The results suggested that copper influenced the degradation of the pesticides in soil by affecting the activity of microorganisms.However, it had catalyst tendency for photodegradation in water system.The difference for the degradation efficiency of pyrethroid isomers in soil was also observed.Copper could obviously accelerate the degradation of some special isomers.     

浅谈事故隐患消减的三个关键环节

长庆油田目前已成立30多年,地处鄂尔多斯盆地,是典型的低渗透油田,生产环境条件苛刻,过程连续性强,原料及产品多为易燃易爆、有毒有害有腐蚀的物质,生产技术复杂,设备种类繁多,生产过程中的风险非常大。加之,企业发展的头20多年,由于投资限制,安全管理水平层次低,生产建设坚持“三从一新”（从简、从快、从省,适用新技术）的原则,安全投入欠帐较多、     

了解外企文化,面试顺利闯关

作为人类社会中的一个重要组成部分,文化无时无刻不在影响和制约着人们的社会行为。外资企业因其所在的不同文化,形成了独特的企业文化与用人理念。真正了解外企文化及其价值观,才能在面试中充分发挥并展示出企业所需要的素养与品质,最终轻松进入职场。     

Polyelectrolyte enhanced ultrafiltration (PEUF) for the removal of Cd(II): effects of organic ligands and solution pH

This study focused on the effects of pH and organic ligands, namely ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and citric acids, on the removal and recovery of Cd(II) in polyelectrolyte enhanced ultrafiltration (PEUF). Polyethylenimine (PEI), which can bind with both positively charged metal ions by coordination bonding and negatively charged ligand-metal complexes by charge attraction, was employed as a chelating polymer. The removal and recovery of Cd species was greatly dependent on the chemistry of organic ligands according to solution pH, particularly being related to the distribution of Cd-ligand complexes at different pH levels. In the presence of EDTA, the dominant Cd species are negatively charged Cd(EDTA)(2-) and CdH(EDTA)(-) over the range of pH levels investigated, interacting with PEI via electrostatic attraction and being less pH dependent. On the other hand, the pH effects of both NTA and citric acid systems are similar to that for the system without organic ligands. This was associated with the fact that free Cd ions were predominant at the acidic pH range in both NTA and citric acid systems.