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61.
苯胺废水处理技术研究进展   总被引:6,自引:0,他引:6  
综述了有毒、难生物降解废水———苯胺废水的各种处理技术及基本原理 ,这些处理技术主要包括物理、化学、生物等方法  相似文献   
62.
In China, volatile organic compound(VOC) control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were based on VOC emission amounts(EA), but never considered the significant differentiation of VOC species in terms of atmospheric chemical reactivity. This will adversely influence the effect of VOC reduction on air quality improvement. Therefore,this study attempted to develop a comprehensive classification method for typical VOC sources in the Beijing–Tianjin–Hebei region(BTH), by combining the VOC emission amounts with the chemical reactivities of VOC species. Firstly, we obtained the VOC chemical profiles by measuring 5 key sources in the BTH region and referencing another 10 key sources, and estimated the ozone formation potential(OFP) per ton VOC emission for these sources by using the maximum incremental reactivity(MIR) index as the characteristic of source reactivity(SR). Then, we applied the data normalization method to respectively convert EA and SR to normalized EA(NEA) and normalized SR(NSR) for various sources in the BTH region.Finally, the control index(CI) was calculated, and these sources were further classified into four grades based on the normalized CI(NCI). The study results showed that in the BTH region,furniture coating, automobile coating, and road vehicles are characterized by high NCI and need to be given more attention; however, the petro-chemical industry, which was designated as an important control source by air quality managers, has a lower NCI.  相似文献   
63.
Objective: The lower extremity of the occupant represents the most frequently injured body region in motor vehicle crashes. Knee airbags (KABs) have been implemented as a potential countermeasure to reduce lower extremity injuries. Despite the increasing prevalence of KABs in vehicles, the biomechanical interaction of the human lower extremity with the KAB has not been well characterized. This study uses computational models of the human body and KABs to explore how KAB design may influence the impact response of the occupant's lower extremities.

Methods: The analysis was conducted using a 50th percentile male occupant human body model with deployed KABs in a simplified vehicle interior. The 2 common KAB design types, bottom-deploy KAB (BKAB) and rear-deploy KAB (RKAB), were both included. A state-of-the-art airbag modeling technique, the corpuscular particle method, was adopted to represent the deployment dynamics of the unfolding airbags. Validation of the environment model was performed based on previously reported test results. The kinematic responses of the occupant lower extremities were compared under both KAB designs, 2 seating configurations (in-position and out-of-position), and 3 loading conditions (static, frontal, and oblique impacts). A linear statistical model was used to assess factor significance considering the impact responses of the occupant lower extremities.

Results: The presence of a KAB had a significant influence on the lower extremity kinematics compared to no KAB (P <.05) by providing early restraint and distributing contact force on the legs during airbag deployment. For in-position occupants, the KAB generally tended to decrease tibia loadings. The RKAB led to greater lateral motion of the legs compared to the BKAB, resulting in higher lateral displacement at the knee joint and abduction angle change (51.2 ± 21.7 mm and 15° ± 6.0°) over the dynamic loading conditions. Change in the seating position led to a significant difference in occupant kinematic and kinetic parameters (P <.05). For the out-of-position (forward-seated) occupant, the earlier contact between the lower extremity and the deploying KAB resulted in 28.4° ± 5.8° greater abduction, regardless of crash scenarios. Both KAB types reduced the axial force in the femur relative to no KAB. Overall, the out-of-position occupant sustained a raised axial force and bending moment of the tibia by 0.8 ± 0.2 kN and 21.1 ± 8.7 Nm regardless of restraint use.

Conclusions: The current study provided a preliminary computational examination on KAB designs based on a limited set of configurations in an idealized vehicle interior. Results suggested that the BKAB tended to provide more coverage and less leg abduction compared to the RKAB in oblique impact and/or the selected out-of-position scenario. An out-of-position occupant was associated with larger abduction and lower extremity loads over all occupant configurations. Further investigations are recommended to obtain a full understanding of the KAB performance in a more realistic vehicle environment.  相似文献   

64.
Pyrolysis is an alternative technology for oil sludge treatment. Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy and Pyrolysis-Gas Chromatography/Mass Spectrometry were employed to investigate the pyrolysis process and products of oil sludge. The pyrolysis process was divided into five stages: drying and gas desorption, oil volatilization, main pyrolysis, semi-coke charring, and mineral decomposition. The main reaction temperatures ranged from 497.6 K to 753.2 K. The products were mainly composed of pairs of alkane and alkene (carbon number ranges from 1 to 27). The mechanisms consisted of random chain scission followed by end chain scission at high temperatures with volatilization occurring during the whole process. This study is useful not only for the proper design of a pyrolysis system, but also for improving the utilization of liquid oil products.  相似文献   
65.
可生物降解材料聚羟基脂肪酸酯(PHA)的合成与应用概述   总被引:3,自引:0,他引:3  
聚羟基脂肪酸酯(polyhydroxyalkanoates,PHA)是很多微生物合成的一种细胞内聚酯,是一种天然的高分子生物材料。PHA具有良好的生物相容性能、生物可降解性和塑料的热加工等性能。文章主要综述了PHA的合成途径与有关应用方面的研究。  相似文献   
66.
废催化剂浸出规律的静态实验方法   总被引:9,自引:1,他引:8  
利用静态浸出实验方法对废催化剂中重金属在不同固水比和浸出次数条件下的浸出规律进行了系统研究。实验发现浸出次数大于3次后,重金属的浸出浓度和浸出速率趋于稳定,同时固水比的增加也没有明显改变废催化剂中重金属的浸出。认为在浸取次数大于3次以后,随着表面溶质的溶解,浸出过程主要为内扩散所控制。  相似文献   
67.
生活垃圾填埋场渗滤液处理技术研究   总被引:7,自引:0,他引:7  
根据处理工艺原理的不同 ,分别介绍生化和物化处理技术、膜处理技术、土地处理技术和蒸发处理技术等处理工艺研究与应用的进展情况 ,同时根据我国填埋场渗滤液的产生特点和处理处置现状 ,展望了我国渗滤液处理工艺的发展趋势。  相似文献   
68.
69.
针对大庆油田低渗透油层水处理工艺存在的问题,设计了金刚砂过滤工艺。进行过滤效果及现场应用稳定性试验,通过工艺的调整及参数的优化,使其出水指标稳定,确定其最佳滤速、反洗再生、级配等运行工艺参数。并对其技术、经济性评价分析,确定为适合油田的精细过滤技术。  相似文献   
70.
论文研究了丙烯酰胺(acrylamide,AA)低剂量多代持续暴露对模式生物秀丽隐杆线虫(Caenorhabditis elegans,C.elegans)的发育、生殖、寿命和捕食行为能力的影响。将线虫暴露于不同剂量水平的AA中,检测对当代线虫的发育周期、后代数量、寿命和捕食行为的影响,结果显示,1.0 mmol·L~(-1)AA水平可诱发当代线虫发育周期延长和后代数量减少(P 0.05),0.05mmol·L~(-1)和0.001 mmol·L~(-1)水平可分别诱发捕食行为能力下降和寿命缩短(P0.05)。进一步选取对当代线虫不产生明显损伤效应的AA剂量,将线虫进行多代持续暴露处理,结果显示,0.01 mmol·L~(-1)AA分别可在第2代g1和第3代g2诱发发育周期延长和后代数量减少(P0.05),0.005 mmol·L~(-1)AA可在第2代g1引起摄食行为能力下降,0.0001 mmol·L~(-1)(约7μg·L~(-1),低于推测人的平均AA暴露水平)的AA在第2代g1即可诱发寿命缩短(P0.05)。以上结果表明AA生物学毒性可以在后代间积累,极低剂量AA多代持续暴露仍可诱发生物学损伤。  相似文献   
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