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1.
目的建立环境水样中痕量铜的浊点萃取(cloud point extraction,CPE)-火焰原子吸收光谱(flame atomic absorption spectrometry,FAAS)测定法。方法样品在p H 9.5的条件下,加入0.4 ml的1 mmol/L 2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)溶液,0.1%氯化钙溶液0.1 ml,5%(W/V)Triton X-114溶液0.8 ml,40℃加热15 min后离心,采用火焰原子吸收光谱法进行检测。结果在2~240μg/L的线性范围内,所得回归方程为A=0.002 7c+0.024 6,r=0.995 8。以3倍信噪比计算,方法的检出限为0.62μg/L,富集倍数为36.58倍,平均加标回收率为96.28%~98.08%,RSD为1.67%~3.13%。结论该方法简单、灵敏,具有良好的重现性,适用于环境水样中痕量铜的测定。  相似文献   
2.
In this study we used a participatory research method, photovoice, to explore community perceptions about environmental health risks, community assets, and strengths in and around an urban, degraded watershed in Northwest Atlanta, Georgia. This watershed, formed by Proctor Creek, is a focal point for redevelopment and infrastructure investments for years to come. Using a community-based participatory research approach, 10 Proctor Creek residents (watershed researchers), and a university partner, engaged in data collection; participatory data analysis; internal discussions; translation of research findings into watershed restoration, community revitalization, remedial action, and policy solutions; and dissemination of results to fellow watershed residents, stakeholders, and decision makers. We present a conceptual model linking the watershed researchers' understanding of urban policies and practice in the Proctor Creek Watershed to environmental, neighborhood and housing conditions and their influence on health outcomes and quality of life. Engaging community members in defining their own community environmental health challenges and assets yielded the following primary themes: 1) threats to the natural environment, 2) built environment stressors that influence health, 3) blight and divestment of public resources, and 4) hope for the future. Residents’ vision for the future of the watershed - a restored creek, revitalized neighborhoods, and restored people - is fueled by a strong connection to history, memory, and sense of place. We demonstrate the value of local knowledge in identifying previously unaddressed environmental health risks in the Proctor Creek Watershed as well as solutions to reduce or eliminate them.  相似文献   
3.
本文用气相色谱法对居住福州、长乐、宁化三个地区270名健康人群发铬含量进行调查。结果表明:福州地区发铬值高于其它两地区,并有非常显著性差异。总体发铬算术平均数与国内外部分地区所报导的结果比较接近,但在性别及年龄间差异不明显。对三个地区发铬值与当地土壤铬含量进行相关分析,r=0.9978,二者呈正相关,并有非常显著性意义。  相似文献   
4.
化学品环境管理与水生实验动物   总被引:3,自引:1,他引:2  
从分析化学品的特性入手,在概述化学品的环境管理对水生实验生物需求和国内外水生实验生物发展现状的基础上,从加强化学品环境管理的科学基础建设出发,对我国水生实验生物的研究与发展的标准化、产业化、必要的资质认可及信息交流提出建议。  相似文献   
5.
Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.  相似文献   
6.
为研究和比较化学致癌物对人呼吸道上皮细胞和纤维母细胞的损伤及损伤后DNA修复合成的差异,作者用直接致癌物4-硝基喹啉-1-氧化物(4-NQO)和间接致癌物3,4-苯并芘(BaP)处理人胚鼻咽、气管上皮细胞和纤维母细胞,用放射自显影术测定这3种细胞的非时序脱氧核糖核酸合成(UDS)。用4-NQO处理后,这3种细胞的UDS均呈明显的剂量依赖(dose dePendency)关系,但气管和鼻咽上皮细胞UDS平均分别是纤维母细胞的3.0和2.4倍。用BaP处理后,气管和鼻咽上皮细胞UDS呈现明显的剂量依赖关系,而纤维母细胞未见这种关系。气管和鼻咽上皮细胞的UDS平均分别是纤维母细胞的8.6和3.0倍。  相似文献   
7.
BACKGROUND: Since chronic infection with mucoid Pseudomonas aeruginosa (PA) is associated with deteriorating lung function, many parents of young children with cystic fibrosis (CF) fear the first PA positive throat swab as a milestone in the progression of the disease. To reduce the risk of PA acquisition from the environment, they perform preventive measures at home or outdoors. METHODS: In an attempt to evaluate the attitude of CF physicians towards these measures and the respective consulting practice, we mailed a questionnaire to all 65 certified paediatric CF centres in Germany. RESULTS: Physicians from 54 (83%) CF clinics replied. They expressed widely different ideas about the impact of the environment for the acquisition of P. aeruginosa, and recommended a large spectrum of preventive measures. Some physicians proposed only few precautions, which focussed on the prevention of cross-infection between patients, whereas others suggested prevention of any contact with moist or wet places, e.g. use different toothbrushes for mornings and evenings, or do without air-conditioning in the car. CONCLUSIONS: CF physicians have different opinions on the risk of PA acquisition from the environment. Doctors who recommend strict precautions could engender a parental fear of a ubiquous threat from invisible bacteria. The resulting extended safety measures might impair the family's quality of life.  相似文献   
8.
Regulations controlling the manufacture and use of carcinogens in the industrial setting of various countries are examined. In addition, the occupational exposure limits (OEL) of chemicals known or suspected to be carcinogenic in humans are listed, and criteria for the establishment of OELs are discussed. It is also stressed that control measures should not be confined to a few developed countries, and it is hoped that attracting attention to their unevenness will contribute to the implementation of a more efficient primary prevention of cancer.  相似文献   
9.
不同病因所诱发的肺癌细胞类型不同已被一些研究所肯定。本文对978例肺癌细胞类型的分析表明:男性以鳞癌为主,女性则腺癌较多。将1980—83年与1984—87年的病例进行比较,发现男性有鳞癌下降和腺癌上升的趋势,女性则相反。鳞癌和小细胞癌均中央型多于周围型,但腺癌未见这种差别。各种细胞类型的肺癌均右肺多见于左肺。吸烟可使鳞癌的发生率上升,在男性尤为明显。接触煤烟尘、炊事活动以及居住点大气污染因素对肺癌细胞类型的构成,尚未发现有明显的影响。  相似文献   
10.
介绍了我国环卫设备的发展现状,并提出了存在的一些问题.根据我国环卫产业政策的有关要求:论述了各种环卫设备研究和开发的方向,指出大力推进环卫机械设备的标准化、系列化、通用化、规模化是社会主义市场经济发展和环卫业发展的需要.  相似文献   
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