吸附法处理洁霉素废水之探讨

从9种吸附剂中筛选出粉末状活性炭、粒状活性炭及高岭土3种对洁霉素废水处理效果较好的吸附剂。并对这3种吸附剂的剂量与COD去除率之间的关系和吸附速度等进行了研究,得出最大COD去除率所对应的吸附剂的最小剂量,并提出3种吸附剂达到吸附饱和所需要的时间。报告了通过正交试验法选出影响吸附效果的主要因素,对处理洁霉素废水有指导意义。     

甲壳素-壳聚糖处理造纸废水的研究

目的 研究由甲壳素的制备壳聚糖对造纸废水处理的效果. 方法考察了pH 值、壳聚糖用量、搅拌速率及絮凝时间等对COD去除率和透光率的影响.结果 得出最佳实验条件: pH值6.56. 7,搅拌速率120 r/min, 絮凝时间12 h, 壳聚糖用量为50 ml废水中加入2 ml 1%的壳聚糖醋酸溶液,在此条件下废水COD去除率可达65%以上,透光率为98%以上,处理效果明显优于无机絮凝剂硫酸铝;[将壳聚糖与硫酸铝进行配比制得复合净水剂处理废水,可进一步提高COD的去除率,去除率可达85%以上.结论 该絮凝剂既可有较高COD去除率,又可以避免二次污染,有较好的环保效果.     

耐铬(Ⅵ)粘质沙雷氏菌CM01的筛选鉴定及其铬(Ⅵ)代谢特性研究

目的 从Cr(Ⅵ)污染环境中分离筛选能耐高浓度Cr(Ⅵ)的菌株,并探究其Cr(Ⅵ)耐受和还原特性。方法 通过驯化,分离筛选高耐Cr(Ⅵ)菌株,观察其形态特征,通过16s rDNA鉴定细菌种属,药敏纸片法确定菌株的药敏情况。探究温度、pH、金属等因素对菌株除Cr(Ⅵ)能力的影响。结果 成功筛选并鉴定出一株沙雷菌CM01,其对卡那霉素、四环素、氨苄西林、庆大霉素敏感,对Cr(Ⅵ)有耐受和还原特性;CM01在Cr(Ⅵ)100mg/L的LB肉汤中,35℃~40℃、pH 6.00~7.00条件下除Cr(Ⅵ)能力最好;Hg、Cr3+、Cd、As等重金属可以抑制其生长,Cu2+可以促进其生长。结论 沙雷氏菌CM01可以耐受高浓度Cr(Ⅵ)且有良好的Cr(Ⅵ)还原能力,可运用到生物修复技术中以处理环境中Cr(Ⅵ)污染。     

拉萨市垃圾填埋场渗沥液水质分析与评价

以西藏拉萨市垃圾填埋场渗沥液为研究对象,分别在不同季节对该场垃圾渗沥液原液和经过渗沥液处理站处理后的渗沥液水样的pH、CODCr、BOD5、NH3-N、色度、悬浮物、As、Cr6+、TN、TP、粪大肠杆菌群数等指标进行了分析与评价。结果表明:拉萨市垃圾填埋场渗沥液中CODCr、BOD5、NH3-N、Cr6+、As、TP和TN的平均浓度分别达到2.01×104、4.24×103、726.09、0.28、0.11、16.92、730.33 mg/L,而且季节的变化对拉萨市垃圾填埋场渗沥液水质中CODCr、BOD5、NH3-N、TN的浓度变化影响较大;CODCr、BOD5浓度低于我国初期垃圾填埋场渗沥液水质的平均浓度,高于我国老龄垃圾填埋场渗沥液水质的平均浓度;经过渗沥液处理站处理后排放口水质各污染物浓度能达到GB 16889—2008生活垃圾填埋场污染控制标准中规定的生活垃圾填埋场水污染排放浓度限值,总体出水水质能够满足城市绿化用水水质标准。     

膜生物反应器处理垃圾渗沥液硝化特性的研究

采用好氧膜生物反应器工艺,以垃圾渗沥液为处理对象,用苯酚及氨氮预驯化的活性污泥启动,在连续进水操作条件下,系统考察该工艺在处理垃圾渗沥液中进水pH和C/N对其硝化特性的影响.结果表明:进水pH对硝化菌活性的影响很明显,当pH为8.0时,氨氮去除率最高,平均在88%左右;进水C/N在4∶1～6∶1时,氨氮去除率与总氮去除率可分别保持在75%～80%和10%～20%,其中75%以上的氨氮转化为硝氮,亚硝氮积累量很小.     

膜生化反应器处理垃圾焚烧厂渗沥液的试验研究

采用成套膜生化反应器(MBR)小试设备对垃圾焚烧厂的渗沥液处理进行了可行性试验研究,并选取了COD、NH3-N的去除率作为主要考察指标.试验表明:膜生化反应器(MBR)工艺技术可行,COD、NH3-N的去除率分别可达99%和98%以上,其出水指标分别达到GB 16889-1997生活垃圾填埋污染控制标准中的三级和二级标准.     

电化学氧化老龄垃圾渗沥液研究

通过不同电极电化学氧化垃圾渗沥液处理的对比研究,选择以Ti/Ru-Ir作为电极阳极材料,研究了电流密度、氯离子浓度、初始pH对电化学氧化垃圾渗沥液的影响。结果表明:电流密度为30 mA/cm2,氯离子浓度5 000mg/L,pH在8.09的情况下,电解6 h垃圾渗沥液,氨氮去除率达到100%,COD去除率为50%,UV254去除率为61.09%,垃圾渗沥液BOD/COD从0.14提高到0.22,垃圾渗沥液生化性得到极大提高。经济性分析表明垃圾渗沥液电化学处理6 h后,氨氮去除率达到100%时,单位能耗为0.08 kW.h/g。     

电离辐射技术在水处理中的应用

本文综述了电离辐射技术处理水中氯酚类、氯苯类、苯胺类、染料、抗生素、重金属等污染物的研究进展;列举了降解机理、辐射源、初始浓度、初始pH值、吸收剂量、污染物去除率、矿化率等重要参数;分析了电离辐射降解污染物效率的影响因素;指出电离辐射在水处理应用中依靠产生自由基等活性粒子,而自由基本身对人体有害,需进一步研究以评估辐射技术的安全性。对电离辐射技术在污染物处理上的应用前景进行了展望。     

不同的抗原修复方法对免疫组化染色结果的影响

目的探讨不同的抗原修复方法对免疫组化染色结果的影响。方法分别采用1）高温高压EDTA（pH9．0）缓冲液修复法;2）高温高压EDTA（pH8．0）缓冲液修复法;3）高温高压柠檬酸盐（pH6．0）缓冲液修复;4）微波炉EDTA（pH9．0）缓冲液修复法;5）微波炉EDTA（pH8．0）缓冲液修复法;6）微波炉柠檬酸盐（pH6．0）修复法。结果采用高温高压修复方式比采用微波修复处理的染色效果要好,大多数抗体使用高pH值的EDTA比用柠檬酸盐（pH6．0）缓冲液修复效果要好。结论高温高压EDTA缓;中液抗原修复方法对大多数抗体来说能达到理想的染色结果,是一种值得推广使用的免疫组化抗原修复方法。     

混凝法处理生活垃圾渗沥液生化出水的研究

以混凝法对垃圾渗沥液生化处理后的出水进行了实验.选用多种混凝剂对渗沥液进行处理,主要以CODCr的去除率为参数,比较其处理效果.利用正交实验对不同的混凝剂、混凝剂最佳用量及最佳pH进行选择.结果表明,在直接加入PFS 1000 mg/L、pH 5～6时处理效果最好.     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

The occurrence of antimicrobial substances in toilet,sink and shower drainpipes of clinical units: A neglected source of antibiotic residues

Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L^?1 to a maximum of 79?mg·L^?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.