企业消防工作标准化建设探讨

目前我国企业正处于消防工作标准化推广阶段。为了提高企业消防工作效率,促进企业安全稳定的发展,通过分析企业消防工作标准化建设中存在的问题,提出应以消防法规为基础,结合企业实际,积极创新推行企业消防工作标准化建设,并以标准化体系建设为抓手,在切实提高消防安全管理水平的同时加强消防设备的维护保养工作,确保消防设备在火灾来临时能够发挥自身应有的作用。     

结构面分布特征对隧道围岩变形影响的数值模拟分析

结构面对隧道围岩变形及稳定性起着决定性作用。运用三维离散元方法(3DEC)研究结构面分布特征,重点是结构面线密度1/λ、强度和倾角对隧道围岩变形的影响,总结了结构面分布与围岩变形特征的关系。结果表明,在结构面强度较低的情况下,结构面线密度对隧道变形的影响较大,其影响可分为两种情况:①λ≤0.2时,围岩的弯曲变形大于沿结构面的剪切变形,属于应力型大变形;②0.2<λ≤0.4时,沿结构面的剪切变形大于围岩的弯曲变形,属于结构型大变形。结构面倾角主要影响围岩大变形发生的位置。将数值模拟结果与国内工程实例实测变形资料相对比,发现一致性较好。本研究结果对隧道支护结构的设计以及施工设计具有借鉴意义与指导作用。     

稠油废水回用热采锅炉工艺研究

以新疆油田红浅稠油区为研究对象进行了稠油废水再生后回用热采锅炉的工艺研究,结果表明采用混凝、过滤、离子交换、除氧工艺对稠油废水进行处理,出水各指标可达到热采锅炉给水水质标准,该工艺在油田的应用具有明显的经济效益和环境效益。     

电晕等离子体烟气脱硫脱硝机理及影响因素探讨

综述了国内外关于电晕等离子体烟气脱硫脱硝机理的研究成果,分析了电压、电极极性、气体温度、水蒸汽和氨气等对去除率的影响,并提出今后发展所需解决的问题.     

超细电气石粉体对水pH值的影响

本文采用行星式球磨机对河北电气石进行超细加工制备超细粉体,并利用其对酸碱水溶液进行处理.结果表明:(1)当球料比10:1、磨矿3 h时效果最佳;(2)电气石能够改变溶液的pH值,可将碱性水溶液的pH值从11.85降至9.30;酸性水溶液的pH值从1.25升至1.62;通过对吸附时间、电气石用量、pH值和吸附温度等单一试验条件和吸附效果之间关系的研究,表明电气石引起溶液pH值变化的原因在于电气石矿物表面羟基化与电气石的电极反应的影响.     

农村面源污染治理的政策与管理服务体系优化——以上海郊区农村为例

农村面源污染控制不仅是技术问题,也是管理体制与机制问题,探讨并完善农村面源污染治理的政策、管理与服务体系已成为当前研究的热点与难点。以上海郊区农村为例,梳理总结农村面源污染及其控制现状;在肯定当前治理效果的同时,识别其局限性,指出农业政策与环境保护政策的不协调、农村发展模式转变下制度与服务体系的相对滞后是根本原因;针对当前农村面源污染重要的贡献者——化肥、农药、畜禽粪便以及农村生活污水,分别从改革农业补贴制度、重构实现农村多重价值的制度以及完善农业生产服务体系等方面给出了治理的对策与建议。     

Effects of salinity on soil bacterial and archaeal community in estuarine wetlands and its implications for carbon sequestration: verification in the Yellow River Delta

Soils from two typical tidal salt marshes with varied salinity in the Yellow River Delta wetland were analysed to determine possible effects of salinity on soil carbon sequestration through changes in soil microbiology. The mean soil respiration (SR) of the salt water–fresh water mixing zone (MZ) was 2.89 times higher than that of the coastal zone (CZ) (4.73 and 1.63?μmol?m^?2?s^?1, respectively, p?Pseudomonas sp. and Limnobacter sp. that might have led to its higher dehydrogenase activity and respiratory rates. Additionally, the CZ possessed more Halobacteria and Thaumarchaeota with the ability to fix CO₂ than the MZ. Significantly lower soil salinity in MZ (4.25?g?kg^?1) was suitable for β-Proteobacteria, but detrimental for Halobacteria compared with CZ (7.09?g?kg^?1, p?相似文献   

夏季富营养化滆湖中沉水植物群落重建及水质净化效果

通过滆湖原位围隔试验分析了不同单种及混种沉水植物群落随环境变化的生长状况及对水质的净化效果.结果表明:(1)夏季,沉水植物生物量的平均值与透明度/水位存在显著线性相关性,进一步表明沉水植物的生长在很大程度上依赖于光强和水深.(2)各植物区(除马来眼子菜区外)的高锰酸盐指数、TN高于空白对照区.(3)对比空白对照区,苦草...     

预应力混凝土结构抗火设计构造措施分析

预应力混凝土结构在火灾下的抗火性能可以通过理论计算得到保证，但是如果预应力混凝土结构的构造措施不合理，也将大大降低结构的抗火性能，甚至引起预应力失效。通过非线性有限元计算讨论了保护层厚度和防火涂料对结构抗火性能的作用，并对规范要求的保护层厚度进行了分析，最后对锚固区的耐火设计提出了建议。     

Characterizing effects of uncertainties in MSW composting process through a coupled fuzzy vertex and factorial-analysis approach

A coupled fuzzy vertex and factorial-analysis approach was developed in this study for systematically characterizing effects of uncertainties in a municipal solid waste composting process. A comprehensive composting process model was also embedded into the system framework and used to address substrate decomposition and biomass growth, as well as the interactions between moisture contents, temperatures, and oxygen concentrations. The applicability of the proposed method was verified through a custom-made pilot-scale composting system. Results from fuzzy simulation indicated that the fuzzy vertex method could effectively communicate implicit knowledge into dynamic simulations and thus provide valuable information for enhancing composting process control under uncertainty. The factorial analysis was effective in quantifying the proportion to which the uncertainty of each single or interactive effect of model parameters contributes to the overall uncertainty of the system outcomes. Thus, sensitive parameters that may lead to errors or unreasonable predictions can be determined. The proposed study system could not only be used in characterizing combined effects of uncertainties for composting processes, but was also applicable to many other environmental modelling systems.