重金属污染土壤中提高植物提取修复功效的探讨

随着对重金属超积累植物研究的加深 ,用植物提取修复技术来改良重金属污染的土壤已逐步进入实用阶段。本文所探讨的提高此技术功效的方法基于两个方面 :提高土壤溶液中重金属的浓度 ,促进植物对重金属的吸收 ;根据已了解的超积累的生理机制可能采取的一些措施     

PCR-DGGE技术在水解酸化-缺氧法处理采油废水的微生物研究中的应用

采用PCR-DGGE技术直接从水解酸化和缺氧反应器中的污泥样品提取DNA,测定部分菌种的16S rDNA V3区片段序列,通过NCBI基因库比对,初步确定不同生物反应器内优势菌种,并进行了多样性指数分析.结果表明,水解酸化反应器中的生物膜与缺氧反应器中悬浮污泥微生物种群结构存在较大的差异,显示了在不同环境条件下,微生物群落结构的连续动态变化过程.     

各种影响因子对电解法预处理医药废水的影响研究

探讨了电解法预处理医药废水时停留时间、电解电压、废水初始浓度、温度和废水pH值等影响因子对去除色度、COD和提高废水可生化性等处理效果的影响，并考察了其应用于工业实际废水处理的可行性。实验结果表明：电解法更适合高浓度医药废水的处理，色度的去除率可达到90％以上；电解时间宜控制在40-60min；电解电压越高，废水COD和色度去除效果越好；在实验温度范围内，温度对色度和COD去除率的影响不大；废水pH值为7．5时电解效果最佳，工程运用宜控制在6—9之间。     

铁炭法处理高浓度难降解表面活性剂废水的研究

就铁炭法对高浓度难降解拉开粉（阴离子表面活性剂）废水的处理效果进行了接近工业化的动态模型实验研究，结果表明酸化铁炭工艺对橡胶工业拉开粉废水具有显著的去除效果。在Fe：C=2：1，pH=4，停留时间60min，曝气量0．1m^3／h时，拉开粉（BX）和COD的总去除率分别约为80％和45％。     

液体旋流分离器分离效率的研究

液体旋流分离器是水环境污染治理的主要设备之一.分离效率是衡量液体旋流分离器分离过程进行完善程度的最重要的技术指标,它能从质与量两方面反映出设备性能的优劣.当前液体旋流分离器设计过程还缺少具体量化的理论依据,为了给液体旋流分离器的设计提供理论依据,通过液体旋流分离器从水中分离固体粒子的性能实验,得出了液体旋流分离器各部结构尺寸、形状、相对比例对分离效率的不同影响程度,提出了结构参数的最佳取值范围.按照本研究提出的设计原则和方法,可以制造出性能优良的液体旋流分离器.     

Variations in exposure to in-vehicle particle mass and number concentrations in different road environments

Road environments significantly affect in cabin concentration of particulate matter (PM). This study conducted measurements of in-vehicle and on-road concentrations of PM10, PM2.5, PM1, and particle number (PN) in size of 0.02–1 µm, under six ventilation settings in different urban road environments (tunnels, surface roads and elevated roads). Linear regression was then used to analyze the contributions of multiple predictor variables (including on-road concentrations, temperature, relative humidity, time of day, and ventilation settings) to measured variations. On-road measurements of PM2.5, PM1, and PN concentrations from the open surface roads were 5.5%, 3.7%, and 16% lower, respectively, than those measured in tunnels, but 7.6%, 7.1% and 24% higher, respectively, than those on elevated roads. The highest on-road PM10 concentration was observed on surface roads. The time series pattern of in-vehicle particle concentrations closely tracked the on-road concentrations outside of the car and exhibited a smoother profile. Irrespective of road environment, the average I/O ratio of particles was found to be the lowest when air conditioning was on with internal recirculation, the highest purification efficiency via ventilation was obtained by switching on external air recirculation and air conditioning. Statistical models showed that on-road concentration, temperature, and ventilation setting are common factors of significance that explained 58%-80%, 64%-97%, and 87%-98% of the variations in in-vehicle PM concentrations on surface roads, on elevated roads, and in tunnels, respectively.

Implications: Inside vehicles, both driver and passengers will be exposed to elevated particle concentrations. However, for in-vehicle particles, there has been no comprehensive comparative study of the three-dimensional traffic environment including tunnels surface roads and elevated roads. This study focuses on the analysis of the trends and main influencing factors of particle concentrations in different road environments. The results can provide suggestions for the driver's behavior, and provide data support for the environmental protection department to develop pollutant concentration limits within the vehicle.     

Photocatalytic activity of TiO2 films grown on different substrates

Titanium dioxide films were prepared on glass, indium-tin oxide (ITO) glass and p-type monocrystalline silicon and studied for the photocatalytic degradation of rhodamine B in an aqueous medium. Raman, AFM, and XPS spectroscopic investigations of these films indicated that microstructure of titanium oxide films were greatly affected by the substrate materials. Rutile was confirmed to be easily formed on the surface of ITO glass, and TiO2 tended to grow as closely packed particles that were elongated strips with an average size of 20 nm, and had lovely contrast with the perfectly round particles grown on p-type monocrystalline silicon. Charge transfer between the film and silicon substrate was verified by surface photovoltage spectra. This may be the real reason why the films grown on ITO glass and silicon substrates exhibit higher photocatalytic reactivity than the film on glass substrate. Moreover, the different surface properties also seem to be responsible for the different activity.     

水解酸化-缺氧法处理采油废水的污染物迁移降解试验研究

水解酸化．缺氧法对采油废水有较好的处理效果，采用GC／MS技术对水解酸化-缺氧法处理采油废水过程中污染物的迁移降解进行的研究表明：水解酸化段和缺氧段对采油废水中碳原子为C6-C9、分子量为100—140的有机物均有较好的降解能力。其中，在水解酸化段中酮类、芳烃得到较好的降解，缺氧段中酚类和醚类化合物降解明显。水解酸化-缺氧工艺对于采油废水中的甲苯和二甲苯具有较好的降解能力。     

某核电厂应急柴油发电机组柴油储罐防爆措施效果评价

核电厂应急柴油发电机组承载着事故工况下为安全停堆设施持续提供应急电源的安全功能,而主油罐是确保该功能正常运行的关键设施,其安全问题影响重大。为客观评价其危险指数,文章利用国际权威分析工具"道(DOW)化学火灾、爆炸危险指数评价法"对该主油罐进行实例评价,并针对性的提出安全改进措施如增加油罐阻隔防爆技术。结果表明,经过安全补偿后,主油罐的火灾爆炸危险指数为"最轻",总体降幅达到61%,其中增加油罐阻隔防爆技术后的危险指数比改进前降幅达到30%,效果显著,有效降低了工程火灾和爆炸风险。     

汶川MS8.0地震前青海地区数字化水温(地温)异常变化分析

介绍了青海地区十个数字化水温井、六个数字化地温井的水温(地温)观测概况。经研究发现,2008年汶川MS8.0地震前,乐都和民和两个井孔出现了中期趋势异常,西宁、乐都和德令哈三个井孔出现了短临异常;从地域来看,异常测点主要集中于西宁-民和断陷盆地内,该区域其它两个正常运行的井孔没有异常,可能和探头与密闭套管末端间的距离过大有关。另外,笔者认为,西宁、乐都、民和井所表现出的中期和短临异常,可能与汶川地震的孕震过程密切相关。