COMPARISON BETWEEN SOLID–PHASE EXTRACTION METHODS FOR THE CHROMATOGRAPHIC DETERMINATION OF ORGANOPHOSPHORUS PESTICIDES IN WATER

A solid-phase microextraction (SPME) procedure has been developed to ex tract eight organophosphorus pesticides (OPs) in water and the method was compared with a conventional solid phase extraction (SPE) technique. The extracted OPs were analyzed by gas chromatography using thermionic specific detection. Both extraction methods presented linear calibration at least over the concentration range investigated (100 to 1000 ng.mL^?1 for SPE and 1 to 100 ng.mL^?1 for SPME). SPME method presented higher sensitivity than SPE. The quantitation limits were between 0.1 to 1.0 ng.mL^?1 for SPME depending upon the analyte, and 100 ng.mL^?1 for SPE. The precision, as measured by the standard deviations (RSD), were in the range 3.6 % to 5.8 % for SPME and 2.4 % to 9.2 % for SPE.

Along with the feature of being a solvent – free sampling technique, SPME offers additional benefits due to its high sensitivity, simplicity, and small size sample required (typically: SPE – 500 mL, SPME – 5 mL).     

面向大型科学工程协同工作的信息推荐

大型科学工程因其庞大的规模使得其在研制时必须是多专业、多部门、多人员协同工作。其研制周期内产生的多维度且格式复杂的海量数据信息让科研人员陷入"信息过载"中,不能很好的利用这些数据。将信息推荐技术应用在大型科学工程的协同研制工作中,提出了面向4D协同信息的推荐模型,并设计了一个面向大型科学工程协同工作的信息推荐系统。该系统通过基于4D技术的信息可视化展示方式向大型科学工程研发人员实时、连续地推荐他们需要的信息,提高研发人员的工作效率。     

Assessment of Seasonal Enrichment of Heavy Metals in Respirable Suspended Particulate Matter of a Sub-Urban Indian City

Heavy metals in respirable suspended particulate matter (RSPM) were analyzed for different seasons, from July 2002 to December 2002, at different locations in Hisar (Haryana, India). The samples were analyzed for Pb, As, Ni, Cu, Mn, Fe and Mg on atomic absorption spectrophotometer (AAS) in air-acetylene flame. The concentration of heavy metals was more in the studied residential area followed by industrial area and commercial area. The concentrations of Fe, As, Ni and Mn were found to be more compared to other metals. Further, the concentrations of all the heavy metals were higher in pre-monsoon (extended summer) and monsoon followed by post-monsoon, autumn and winter. Meteorology played an important role in concentration of heavy metals in RSPM. Turbulent conditions resulted in higher concentration owing to re-suspension and external input whereas, low wind speed, low temperature and high relative humidity favoured low concentration of the pollutants. The evaluation of enrichment factor revealed that Pb, As, Ni, Cu, and Mn are emitted, chiefly from anthropogenic sources and Fe and Mg are associated with natural sources.     

Reduced nitrogen has a greater effect than oxidised nitrogen on dry heathland vegetation

We investigated the effects of different ratios of reduced (NH4+) versus oxidised (NO3(-)) nitrogen in deposition on heathland and species-rich grassland vegetation at high nitrogen deposition levels in large mesocosms filled with nutrient-poor soils to which different NH4+/NO3(-) ratios were applied. The response of the forbs, Antennaria dioica, Arnica montana, Gentiana pneumonanthe, Thymus serpyllum, the grasses Danthonia decumbens, Deschampsia flexuosa, Nardus stricta and the shrub Calluna vulgaris was recorded. The forb A. dioica and the grass D.decumbens preferred low NH4+/NO3(-) ratios and were characterised by a negative correlation between NH4+/NO3(-) ratios and biomass and survival, whereas the grasses N. stricta and D. flexuosa showed no correlation with NH4+/NO3(-) ratios. Lime addition eliminated the negative effects of high NH4+ concentrations in deposition for A. dioica and the grass D. decumbens. The implications of these findings for heathland vegetations are discussed.     

我国安全生产发展趋势的计量分析

在分析我国1990—2005年安全生产指标变动规律的基础上,建立了安全生产指标的长期趋势模型,并对安全生产指标进行了预测。同时,分别以人均GDP指标为解释变量、安全生产指标为被解释变量建立了计量关系模型,以此反映我国安全生产随经济发展的变动规律。研究表明,从业人员10万人死亡率呈波动上升趋势,与人均GDP指标存在显著二次关系;亿元GDP死亡率指标呈现持续下降趋势。这表明在我国经济总量快速增长的过程中安全负担水平得到了较好控制。     

生产安全预警预报指标体系研究

分析生产安全预控指标体系建立的必要性,指出当前生产安全预控研究现状及存在的问题;提出建立生产安全预控指标的改进模式;基于生产安全预控研究现状,建立企业层面的生产安全预警指标体系和政府部门宏观决策层的生产安全预报指标体系;对现有的预警预报程序进行改进,设计从企业层面到国家层面的生产安全预警预报和控制程序,为生产安全指数的计算提供了依据。政府部门可通过自下(企业)而上(地区或国家)的程序依次计算安全指数,再由上而下查找问题,从而给出控制目标和措施。     

基于项目双分解结构的区域应急动态网络计划研究

为解决区域性突发事件应急管理计划的一致性及时效性问题,提出基于区域应急任务分解结构和区域应急组织分解结构的分级动态网络计划方法。构建了应急任务分级网络模型及组织分层网络结构及资源列表模型。诠释任务分解规则及应急组织结构特征,最后整合双分解网络结构,推导出区域性应急管理分级动态网络计划生成模型。为区域性应急预案体系的编制提供了技术方法指导,对提高应急计划的实际可操作性具有现实意义。     

安全生产与经济社会发展之关系的研究——以广东省为例

以广东省为例,通过对省内近几年的经济社会发展状况和安全生产事故的相关指标进行统计分析,从事故对经济社会影响和安全生产与GDP、产业结构、产业集群及区域差异的相互作用等方面分析安全生产与经济社会发展的相互作用,阐明安全生产状况与一定时期内社会经济发展水平有着密切的关系,即在不同的经济社会发展阶段,安全生产状况呈现不同的特点和发展趋势,而一定时期内的安全生产水平对经济社会发展有着重要影响。针对新时期的安全生产状况提出相应的对策,以促进区域内经济社会的和谐发展,对全省区域内的安全生产工作规划有着借鉴和参考作用。     

Characteristics of Hazardous Airborne Dust Around an Indian Surface Coal Mining Area

Surface coal mining creates more air pollution problems with respect to dust than underground mining . An investigation was conducted to evaluate the characteristics of the airborne dust created by surface coal mining in the Jharia Coalfield. Work zone air quality monitoring was conducted at six locations, and ambient air quality monitoring was conducted at five locations, for a period of 1 year. Total suspended particulate matter (TSP) concentration was found to be as high as 3,723 μg/m³, respirable particulate matter (PM10) 780 μg/m³, and benzene soluble matter was up to 32% in TSP in work zone air. In ambient air, the average maximum level of TSP was 837 μg/m³, PM10 170 μg/m³ and benzene soluble matter was up to 30%. Particle size analysis of TSP revealed that they were more respirable in nature and the median diameter was around 20 μm. Work zone air was found to have higher levels of TSP, PM10 and benzene soluble materials than ambient air. Variations in weight percentages for different size particles are discussed on the basis of mining activities. Anionic concentration in TSP was also determined. This paper concludes that more stringent air quality standards should be adopted for coal mining areas and due consideration should be given on particle size distribution of the air-borne dust while designing control equipment.     

食品质量与安全专业课程改革实践

专业课程改革以职业实践活动为导向,以职业资格认定为目标,以工学结合为切入点,将职业学习与工作领域相统一作为改革的总体思路。食品质量与安全专业经过努力,专业课程改革建设中取得了一定的成效,至2008年已建成《食品微生物学及微生物检验》一门院级精品课。