工程技术管理人员安全生产责任的落实

安全生产责任制度,是现代企业工程施工安全生产工作的基本制度,是落实企业安全生产主体责任、规范安全管理流程的基本法则。每一个建筑施工企业都会制定出从企业董事长、总经理到各个管理岗位,直到基层作业人员的安全生产责任制。在施工现场安全生产工作中,工程技术人员的安全责任落实是安全管理链条的重要环节。     

Nitrogen loss through lateral seepage in near-trench paddy fields

A near-trench paddy field experiment with five urea application rates (0-360 kg N ha(-1) in 90-kg increments) was conducted on a paddy soil in the Taihu Lake Region of China to elucidate N losses through lateral seepage during three rice (Oryza sativa L.) growing seasons. The total N (Nt), NH4(+) -N, and NO3(-) -N concentrations in the lateral seepage water increased with increasing N rates. The seasonal Nt fluxes by lateral seepage varied from 6.8 to 25.6 kg N ha(-1) for urea application rates of 90 to 360 kg N ha(-1). Lateral seepage accounted for 4.7 to 6.6% of the Nt applied, implying that lateral seepage was an important pathway of N loss from near-trench paddy fields. The cumulative N loss via lateral seepage was significantly related to N fertilization rate (P = 0.05). Floodwater level was also identified as a main factor affecting N losses via lateral seepage from paddy fields, as indicated by a positive linear relationship (R2 = 0.43) between floodwater level and daily lateral flow during the flooded period (P = 0.05). Under the conditions of these experiments, a shallow floodwater depth of 50 mm, urea application rates of 90 kg N ha(-1) or less, and no rainfall within 1 wk after N application reduced N losses by lateral seepage from paddy fields.     

Adsorption of Pb and Cd on the natural surface coatings (NSCs) in the presence of organochlorine pesticides: a preliminary investigation

Adsorption of Pb and Cd in the presence and absence of organochlorine pesticides (OCPs) on natural surface coatings (NSCs), which were collected in the Nanhu Lake in Changchun, China, was measured in order to investigate the effect of the OCPs on the adsorption of heavy metals on the NSCs. Adsorption of Pb/Cd was carried out under controlled laboratory conditions (mineral salt solution with defined species, ionic strength 0.05 mol/l, 25 degrees C and pH 6.0) with initial Pb and Cd concentrations ranging from 0.2 to 2.5 mol/l. The classical Langmuir adsorption isotherm was applied to estimate the equilibrium coefficients of the adsorption of Pb and Cd on the NSCs. Adsorption interference between Pb/Cd and the OCPs on the NSCs indicated that the adsorption of Pb/Cd on the NSCs was influenced by the OCPs, and competitive adsorption between Pb and the OCPs was observed while adsorption of Cd was enhanced by addition of the OCPs. Adsorption data fit the Langmuir isotherm well for the NSCs treated with the OCPs at different equilibrium concentrations. The results showed that the amount of adsorbed Pb decreased by more than 40% while the amount of adsorbed Cd increased by over 60% with an increase in the initial concentrations of the OCPs ranging from 0 to 5.0 microg/l and that adsorption of Pb/Cd on the NSCs was strongly affected by the OCPs. This preliminary study highlights the importance of the OCPs on the NSCs in controlling the transport, fate, biogeochemistry, bioavailability and toxicity of trace metals in aquatic environments.     

建立环境预警监测体系的探讨

要实现环境保护的"三个转变",环境预警监测处在最前沿.如何建立环境预警监测体系,充分发挥各组成部分的功能,成为目前环境监测的中心工作.本文从环境预警监测工作的作用和重要性入手,分析了体系的组成部分:人才、技术能力和监测质量.     

Stormwater runoff quality from different surfaces in an urban catchment in Beijing, China

Urban stormwater runoff quality, widely investigated around the world, has been monitored less in Beijing, China, which impedes the municipal government to use best management practices to protect surface water. In this study, rainwater and stormwater runoff samples from roofs, roads, and a lawn on the campus of the Research Center for Eco-Environmental Sciences (RCEES) (Beijing, China) and from a ring road, with heavy traffic, have been sampled and analyzed for 31 storm events from June 2004 to August 2005. Total suspended solids (TSS), chemical oxygen demand (COD), 5-day biochemical oxygen demand (BOD5), total nitrogen, and total phosphorus concentrations in rainwater and runoff ranged over 2 or more orders of magnitude, meaning that the highest concentration of a certain pollutant did not always occur in a certain kind of runoff. Runoff contained significantly higher concentrations of pollutants than rainwater. On the campus of RCEES, TSS and total phosphorus in runoff samples from the lawn and roads were significantly higher than those from roofs, while the COD, BOD5, and total nitrogen concentrations were not significantly different in runoff among surfaces. Compared with runoff from the roads on campus, runoff from the ring road contained more COD and total nitrogen, but less TSS, BOD5, and total phosphorus. All pollutants measured in runoff from roofs on campus and from the ring road showed a peak concentration in starting runoff, which then decreased sharply. The peak concentrations of COD, BOD5, total nitrogen, and total phosphorus in the roof runoff increased with the increase in time of the antecedent dry period. Thus, urban stormwater pollution control, especially for first-flush control, is of great importance for the full use of rainwater and prevention of water pollution.     

基于专利的企业环境技术创新水平研究

以专利为衡量技术创新水平指标,对国内外企业环境技术创新水平的差异进行了分析.研究结果表明,1986～2005年期间,国内外企业环境技术创新水平逐年增强,不过我国企业的环境技术创新主体地位仍未建立;同国外企业相比,我国企业的原始技术创新能力不强.由于国内企业技术创新受到经济因素的影响,节约资源和清洁能源类环境技术比污染控制技术较多一些.在环境技术创新领域,无论国内还是国外,规模大、国际知名度高的企业占据了重要地位.基于我国企业仍未具备很强的环境技术创新能力,建议国家在构建环境技术创新体系时,应增加企业环境技术创新的经济、人力投入,尤其需要加强对大型企业环境技术创新的支持力度,发挥其规模效应.     

ORP控制在硫化物生物氧化成单质硫过程中的应用

试验采用气升式反应器,接种实验室自行培养的排硫硫杆菌种,在进水pH值为7.0±0.2,温度控制在30±2℃条件下,研究了以ORP为控制参数在硫化物生物氧化成单质硫过程中的应用,并考察了pH和污泥硫负荷对ORP及硫化物生物氧化的影响.结果表明,硫化物去除率和硫酸根生成率均随ORP的降低而下降,不同容积负荷下,控制合适的ORP均可得到单质硫的最大生成率;当ORP为-380～340 mV,pH为7.85～8.63,污泥硫负荷为8.4 kg S/(kg MLSS·d)时,反应器运行状况良好.     

大长径比油气管道空间爆炸事故分析——以中国石油新疆油田分公司"8·7"稠油热采井口爆炸事故为例

为分析大长径比管道内气体爆炸事故的原因,以新疆克拉玛依油田克浅10井区"8·7"23123井口爆炸事故为例,进行物理爆炸和化学爆炸的理论计算,并分析井口爆炸事故过程.物理爆炸计算与分析表明,爆炸可产生的压力为18.46 MPa,小于采油(气)井口装置105 MPa的爆破压力,因此,该爆炸不属于蒸汽过热引起的物理爆炸.化学爆炸计算表明,油管内发生化学爆炸产生的高温达到2 666.7 ℃,可以使钢材强度受到破坏;化学爆炸的爆轰压力为122.4 MPa,大于井口装置能承受的爆破压力,说明是化学爆炸产生的爆轰压力摧毁了井口装置.计算与分析的结果可以为防止类似事故的发生提供参考.     

株洲市清水塘工业区地表水底泥重金属污染评价

对株洲市清水塘工业区地表水底泥重金属含量进行了检测,并采用地积累指数法进行了评价.结果表明,该区底泥受到重金属极强污染,各溪港污染程度为老霞湾港铜塘港>霞湾港,各元素污染程度为CAHgPbAs;霞湾港由于底泥量最大,其重金属含量最大,Cd、Hg、Pb、As分别占总量的69.45%、80.62%、66.46%和86.56%;霞湾港中污水厂～河口段重金属含量最大,CA、Hg、Pb、As分别占该港总量的98.50%、56.06%、18.14%和52.09%.     

Rapid quantification of polycyclic aromatic hydrocarbons in hydroxypropyl-beta-cyclodextrin (HPCD) soil extracts by synchronous fluorescence spectroscopy (SFS)

Synchronous fluorescence spectroscopy (SFS) was directly applied to rapidly quantify selected polycyclic aromatic hydrocarbons (PAHs: benzo[a]pyrene and pyrene) in aqueous hydroxypropyl-beta-cyclodextrin (HPCD) soil extract solutions from a variety of aged contaminated soils containing four different PAHs. The method was optimized and validated. The results show that SFS can be used to analyse benzo[a]pyrene and pyrene in HPCD based soil extracts with high sensitivity and selectivity. The linear calibration ranges were 4.0x10(-6)-1.0x10(-3)mM for benzo[a]pyrene and 6.0x10(-6)-1.2x10(-3)mM for pyrene in 10mM HPCD aqueous solution alone. The detection limits according to the error propagation theory for benzo[a]pyrene and pyrene were 3.9x10(-6) and 5.4x10(-6)mM, respectively. A good agreement between SFS and HPLC was reached for both determinations of PAHs in HPCD alone and in soil HPCD extracts. Hence, SFS is a potential means to simplify the present non-exhaustive hydroxypropyl-beta-cyclodextrin (HPCD)-based extraction technique for the evaluation of PAH bioavailability in soil.