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91.
含锌废水处理技术的研究进展   总被引:9,自引:0,他引:9  
综述了传统的物理化学法和生物法处理含锌废水的原理,系统阐述了其研究进展.微生物固定技术是一种新兴而有效的生物处理技术,尤其是硫酸盐还原菌固定化技术,将厌氧活性污泥包埋,构建稳定高效的微生物体系,以加强其抗毒性和处理效率.因此,在含锌废水处理方面具有很大的发展潜力,有望得到广泛应用.  相似文献   
92.
我国近岸海域微生物源示踪监测技术的研发   总被引:3,自引:1,他引:2  
通过对我国近岸海域陆源性非点源污染污染贡献率及其危害性剧增现状的分析,强调了在我国开展污染源示踪检测技术研发的必要性。在总结了国外治理非点源污染的经验———微生物源示踪技术研究和应用现状的基础上,介绍了我国近岸海域微生物源示踪检测技术研发的设计思想。从而阐明,传统的环境监测指标和方法已不能满足发展的需要,集监测、溯源和示踪为一体,适应于我国国情的近岸海域非点源污染源监测技术的研发势在必行。  相似文献   
93.
某复合型地铁车站站台防排烟方案研究   总被引:3,自引:0,他引:3  
姚斌  左剑  李元洲  黄平 《火灾科学》2006,15(3):172-177
在地铁站台火灾中,机械排烟和补风对于有效排出站台烟气至关重要,地铁设计规范要求采用正压送风方式来防止烟气经扶梯和楼梯流入站厅层。对于复合型地铁站台而言,站厅层可能与其它建筑共用,建筑面积较大,难以提供足够的风压进行正压送风。本文利用性能化防火设计方法对多种站台防排烟方案进行研究,并提出了分析流程。本文还针对某实际工程案例验证了这一流程的可行性,并据此选择了一种将机械排烟和补风有机结合的防排烟方案。本文的研究工作对其它类型地铁站台防排烟方案具有参考价值。  相似文献   
94.
The process of the rice straw degradation in the fermentor with aeration at 290 ml/h was studied. The results of dissolved oxygen (DO) indicated that the optimum DO during cellulose degradation by microbial community MC1 ranged from 0.01 to 0.12 mg/L. The change model ofpH values was as follows: irrespective of the initial pH of the medium, pH values decreased rapidly to approximate 6.0 after being inoculated within 48 h when cellulose was strongly degraded, and then increased slowly to 8.0--9.0 until cellulose was degraded completely. During the degradation process, 15 kinds of organic compounds were checked out by GC-MS. Most of them were organic acids. Quantity analysis was carried out, and the maximum content compound was ethyl acetate which reached 13.56 g/L on the day 4. The cellulose degradation quantity and ratio analyses showed that less quantity (under batch fermentation conditions) and longer interval (under semi-fermentation conditions) of rice straw added to fermentation system were contributed to matching the change model of pH, and increasing the quantity and ratio of rice straw degradation during cellulose degrading process. The highest degradation ratio was observed under the condition office straw added one time every five days (under semi-fermentation conditions).  相似文献   
95.
A new resonance scattering method was proposed for the determination of chlorite, basing on the resonance scattering effect of rhodamine dye. In HCl-sodium acetate buffer solution, chlorite oxidizes 1- into 12 and the reaction of 12 and excess 1- results in If. It is respectively combined with rhodaminc dyes, including rhodamine B (RhB), butyl rhodamine B (b-RhB), rhodamine G (RhG) and rhodamine S (RhS), to form association complex particles, which exhibit stronger resonance scattering (RS) effect at 400 nm. The chlorite concentration of ClO2 in the range of 0.00726-0.218 μg/ml, 0.0102-0.292 μg/ml, 0.00726-0.145 μg/ml and 0.0290- 0.174 μg/ml is respectively linear to the RS intensity of association complex particle systems at 400 nm for the RhB, b-RhB, RhG and RhS. The detection limits of the four systems were respectively 0.00436, 0.00652, 0.00580 and 0.01450μg/ml ClO2^-. In the four systems, the RhB system possesses good stability and high sensitivity. It has been applied to the analysis of chlorite in wastewater with satisfactory results.  相似文献   
96.
为“挖掘”输油泵机组风险根源,降低设备预知性维护难度,结合输油泵多准则风险评价,提出1种基于等级全息建模的输油泵机组风险根源辨识方法,运用等级全息建模方法将输油泵系统分解为泵体结构、管理因素、环境因素、操作因素、技术因素、运行因素、设备安装7个子系统进行定性和定量分析。结果表明:相比危险与可操作性分析(HAZOP)、事故树分析(FTA)等传统风险辨识方法,等级全息建模(HHM)对轴承等关键部件以及压力等运行参数的监测更为深入,能够有效辨识输油泵机组高风险情景,提升输油泵的风险辨识效率。  相似文献   
97.
为提高燃气管线突发事件应急处置决策水平和应急响应能力及效率,采用复杂网络理论和灾害链演化机理对燃气管线破裂灾害事件影响进行耦合分析,构建燃气管线破裂灾害链网络和风险评估模型,并计算得出燃气管线破裂灾害链风险度。为更准确地表达无传播路径的灾害事件之间的关系,将灾害网络中所有最短路径长度的最大值作为其最短路径长度,计算表明这种算法更符合灾害传播实际情况。结果表明:通过燃气管线破裂灾害链风险分析,能够为燃气管线灾害风险控制措施和方案制定提供参考,有利于提高燃气管线破裂灾害事件的应急处置能力和决策水平。  相似文献   
98.
Abstract

The roles of PM2.5-induced mitochondrial damage and oxidative stress on mast cell degranulation were examined in vitro. Mast cells were treated with suspensions of PM2.5 in Dulbecco’s modified Eagle’s medium at concentrations from 25 to 200?mg/L in the absence or presence of 10?mmol/L N-acetyl-L-cysteine. Biological effects and mitochondrial function were assessed by determining cell viability, β-hexosaminidase release, interleukin-4 secretion, reactive oxygen species generation, adenosine triphosphate production, potential alteration of mitochondrial membrane, and activities of mitochondrial electron transport chain complexes I and III. Exposure of mast cells to PM2.5 induced reduction of adenosine triphosphate production, collapse of mitochondrial membrane potential, and inhibition of the activity of complex III. Co-treatment of mast cells exposed to PM2.5 with N-acetyl-L-cysteine attenuated cytotoxicity and the production of reactive oxygen species, and decreased the release of β-hexosaminidase and interleukin-4. Evidently, PM2.5-induced oxidative stress plays an essential role in mitochondrial toxicity and mast cell activation.  相似文献   
99.
Culturable heterotrophic bacterial and phytoplanktonic densities were investigated at four sites in the Southern Adriatic Sea (Brindisi, S. Cataldo, Otranto and S. M. di Leuca) over an annual cycle. The main phytoplankton groups, the bacterial biodiversity, as well as the faecal contamination indicators were determined. Culturable bacterial numbers averaged 4.8 ± 0.2 log CFU ml−1 whereas phytoplankton numbers averaged 2.1 ± 0.4 log cells ml−1. Relationships between culturable bacteria, phytoplankton and the environmental factors were established. Bacterial and phytoplankton densities usually depended significantly on temperature, dissolved oxygen, phosphate and nitrite only in the S. Cataldo transect. In all the examined transects phytoplankton showed a bloom during the January–February period followed by a bacterial peak during the February–March period. Thus we can suppose that the phytoplankton winter bloom is responsible for the availabily of organic matter for bacterial populations in the following months in this oligotrophic ecosystem.  相似文献   
100.
构建了一个基于人工神经网络的约束型城市扩展CA模型。利用该模型,预测了北京市东部平原区在3种情景规划之下的未来50年的城市形态,为不同的城市发展模式之间的比较分析奠定基础。然后以2024年的北京东部平原区模拟城市形态为基准,从自然生态功效、社会服务功效、经济利益功效3个方面对3种规划模式进行了情景分析,从而系统的比较了3种规划模式的复合生态功效,为城市规划决策提供有力的支持。  相似文献   
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