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991.
安全管理决策支持系统及其最新进展   总被引:1,自引:0,他引:1  
安全管理是企业管理的重要组成部分,是实现安全生产的有力保证.决策支持系统是实现安全管理定性与定量分析有机结合的有效手段.该文结合安全管理,简要阐述了决策支持系统产生的背景、内容和发展趋势.介绍了作者在企业安全管理决策支持系统研制方面的主要结果和进一步工作的构想.  相似文献   
992.
The aim of this study was to characterize the features of a Cd-, Pb-, and Zn-resistant endophytic fungus Lasiodiplodia sp. MXSF31 and to investigate the potential of MXSF31 to remove metals from contaminated water and soils. The endophytic fungus was isolated from the stem of Portulaca oleracea growing in metal-contaminated soils. The maximum biosorption capacities of MXSF31 were 3.0?×?103, 1.1?×?104, and 1.3?×?104 mg kg?1 for Cd, Pb, and Zn, respectively. The biosorption processes of Cd, Pb, and Zn by MXSF31 were well characterized with the pseudo-second-order kinetic model. The biosorption isotherm processes of Pb and Zn by the fungus were fitted better with the Langmuir model, while the biosorption processes of Cd was better fitted with the Freundlich model. The biosorption process of MXSF31 was attributed to the functional groups of hydroxyl, amino, carbonyl, and benzene ring on the cell wall. The active biomass of the strain removed more Cd, Pb, and Zn (4.6?×?104, 5.6?×?105, and 7.0?×?104 mg kg?1, respectively) than the dead biomass. The inoculation of MXSF31 increased the biomass of rape (Brassica napus L.), the translocation factor of Cd, and the extraction amount of Cd by rape in the Cd?+?Pb-contaminated soils. The results indicated that the endophytic fungus strain had the potential to remove heavy metals from water and soils contaminated by multiple heavy metals, and plants accumulating multiple metals might harbor diverse fungi suitable for bioremediation of contaminated media.  相似文献   
993.
The endophytic bacterium isolated from Scirpus triqueter was proved to be an oil-degraded bacterium. A pot experiment was conducted to investigate the removal ratio of diesel under the combined effect of oil-degraded microorganism (Pseudomonas sp. J4AJ) and S. triqueter. The effect of diesel on plant growth parameters, soil enzymes and microbial community was assessed after 60 days. The results showed that the soils which were planted with S. triqueter and inoculated with J4AJ displayed the highest removal ratio (54.51?±?0.15 %) after 60-day experiment. However, the removal ratio of J4AJ-treated soils was 38.97?±?0.55 %. Diesel was toxic to S. triqueter, as evidenced by growth inhibition during the experimental period. However, the plant height and stem biomass in the soils inoculated with J4AJ significantly increased. The combined effect of S. triqueter and J4AJ improved the enzyme activities of the catalase and dehydrogenase in the contaminated soil. The diversity index in soils under the effect of S. triqueter combined with J4AJ was lower than that of the other soil samples. The principal analysis of phospholipid fatty acid signatures revealed that the combined effect of S. triqueter and J4AJ increased the differences of soil microbial community structure with the other treatments.  相似文献   
994.
Pollutants including heavy metals and brominated flame retardant were detected in 10 types of production wastes from a typical printed circuit board manufacturing plant, and their inventories were estimated. Rinsing water from etching process had the highest concentrations of copper (665.51 mg/L), lead (1.02 mg/L), nickel (3.60 mg/L), chromium (0.97 mg/L), and tin (1.79 mg/L). Powdered solid waste (SW) from the cut lamination process contained the highest tetrabromobisphenol-A (TBBPA) levels (49.86 mg/kg). Polybrominated diphenyl ethers (PBDEs) were absent in this plant, in agreement with the international regulations of PBDE phase out. The pollutant inventories in the wastes exhibited in the order of copper >?>?zinc?>?tin?≈?nickel?>?lead?>?chromium >?>?TBBPA. The potential environmental impact of pollutants in SW during production and disposal were further investigated. A high partitioning of pollutant concentration between the total suspended particle and SW (?0.10?K TS?相似文献   
995.
为分析水质达标的处理站回注水在注水管线流动的过程中水质逐渐变差的原因,通过现场实际运行过程,分别获取了水处理站、注水站和注水井底各段的水样,进而测定了各水样的相关水质指标,并且分析了水中悬浮物的元素组成。实验结果表明,回注水在注水管线中引起管线腐蚀,腐蚀产生的Fe2+、Fe3+进一步导致溶解性油含量和悬浮固体的增加,最终得出管线的腐蚀是引起水质变差的主要原因。  相似文献   
996.
Is emission intensity of carbon dioxide (CO2) spatially correlated? What determines the CO2 intensity at a provincial level? More importantly, what climate and economic policy decisions should the China’s central and local governments make to reduce the CO2 intensity and prevent the environmental pollution given that China has been the largest emitter of CO2? We aim to address these questions in this study by applying a dynamic spatial system generalized method of moment technique. Our analysis suggests that provinces are influenced by their neighbours. In addition, CO2 intensities are relatively higher in the western and middle areas, and that the spatial agglomeration effect of the provincial CO2 intensity is obvious. Our analysis also shows that CO2 intensity is nonlinearly related to gross domestic product, positively associated with secondary-sector share and foreign direct investment, and negatively associated with population size. Important policy implications are drawn on reducing carbon intensity.  相似文献   
997.
Studies of nest-site selection and reproduction are essential for bird species assessment and conservation. We compared breeding habitats and random sites within a secondary cavity-nesting bird, Yellowrumped Flycatcher (Ficedula zanthopygia), in a 5-year studying period in northeast China. We also modeled the effects of factors on daily nest survival rates. The flycatcher nest cavities were mostly located in tree trunks, with only 15% found in limbs. They often located their nests in east and south direction (45°–180°) with dense canopy cover surrounding the nest trees. Yellow-rumped Flycatcher nest-site selection appears to be nonrandom, such that they select nest sites with higher tree density and higher canopy closure. Yellowrumped Flycatcher daily nest survival rate was 0.9731 ± 0.007. Daily nest survival increased with increasing percent cover of canopy closure and decreased with the distance closing to the edges. The causes for nest failure were mainly nest usurpation by other secondary cavity-nesters. Predation rate and the competition for cavities with other secondary cavity-nesters may constrain the ability of Yellow-rumped Flycatchers to optimize nest nest-site selection.  相似文献   
998.
随着相当数量的海上油田接近或者超过服役年限,越来越多的平台需要弃置。文章介绍了国内外海洋石油平台弃置的环境管理法律法规,以某海洋石油平台的拆除为例,从对海洋环境影响最大的油井永久封堵、导管架桩基的切割和海底管线拆除与回收三个方面,合理选择弃置方案,并分析了石油平台弃置对海洋的环境影响。最后针对海洋石油平台弃置过程和弃置后凸显的问题,提出了科学、可行的环境管理建议。  相似文献   
999.
大田条件下施加组配改良剂对蔬菜吸收重金属的影响   总被引:3,自引:0,他引:3  
通过向湘南某矿区周边重金属污染的农田施加不同添加量(0、2、4和8 g/kg)的组配改良剂HS(海泡石+石灰石),分析农田土壤理化性质变化和土壤重金属及其交换态含量的影响、空心菜和辣椒可食部位和根部位重金属含量的影响。结果表明,施用2~8 g/kg组配改良剂HS能使2种蔬菜土壤p H值和CEC含量显著增加,使交换态重金属含量大幅降低,且不同程度地降低了空心菜和辣椒可食部位及根部位的重金属含量。与对照相比,空心菜和辣椒可食部位重金属Pb、Cd、Cu、Zn的降幅分别为:21.1%~47.5%、6.5%~31.0%、57.7%~80.0%、65.3%~92.0%和27.3%~74.5%、29.8%~62.0%、55.4%~76%、37.8%~77.1%;根部位的重金属含量也有明显降低。当添加量为8 g/kg时,2种蔬菜可食部位和根部位重金属含量降低幅度最大。由此可知,组配改良剂HS的施用对2种蔬菜吸收土壤重金属起到有效的抑制作用。  相似文献   
1000.
Adsorption of ammonium on biochar prepared from giant reed   总被引:1,自引:0,他引:1  
Giant reed was used as precursor for making biochar in order for the adsorption of NH4 +–N from aqueous solution. And the adsorption of the product to NH4 +–N was examined. The surface features of biochar were investigated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy/energy dispersive spectrometer (SEM-EDS), and X-ray diffraction (XRD). XRD patterns showed several peaks and correspond to the high amount of crystalline material. The crystals contain KCl, K2O, CaO, MgO, and SiO and possess high surface area which enhances adsorption. The influence of different parameters such as initial concentration, adsorption time, pH, and ionic strength has been carried out. The adsorption could reach equilibrium through 24 h reaction and had the best adsorption amount at the solution pH values from 7 to 9. The cation has great influence on the adsorption of NH4 +–N, whereas the anion exerted a weaker effect. The adsorption followed pseudo-first-order and pseudo-second-order models. And the intraparticle diffusion and desorption studies further elucidated that the mechanism of adsorption on the product was ion exchange. The product equilibrium data was well described by the Langmuir and Freundlich model. The maximum adsorption capacities were 1.490 mg/g. Biochar derived from giant reed at 500 °C was suggested as a promising adsorbent for the removal of NH4 +–N from slightly polluted wastewater.  相似文献   
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