金华地区PM2.5中的极性有机示踪物

用GC/MS,对金华地区3个采样点、四个季节,225个PM_(2.5)样品中10种极性有机示踪化合物进行了分析,包括天然源:3个异戊二烯SOA示踪物、1个α-蒎烯SOA示踪物和2个真菌孢子示踪物,和人为源:1个甲苯SOA示踪物、3个生物质燃烧示踪物.结果表明,异戊二烯SOA示踪物浓度为3.41~48.50 ng·m~(-3),α-蒎烯SOA示踪物浓度为2.45~25.40 ng·m~(-3),甲苯SOA示踪物为4.75~39.80 ng·m~(-3).各SOA示踪物均有明显的季节变化,其中,异戊二烯SOA示踪物呈夏季秋季≈春季冬季,α-蒎烯SOA示踪物夏季春季≈秋季冬季,甲苯SOA示踪物秋季夏季春季冬季.估算得出甲苯SOC对OC的贡献为3.03%~24.50%,而来源于生物质燃烧的有机碳对OC的贡献可以达到1.23%~42.80%.表明人为源排放前体物的二次转化以及生物质燃烧是金华地区大气细颗粒物污染的重要来源.     

苯甲酸生产废水的处理与资源化

为有效地回收甲苯液相氧化法生产苯甲酸的工业废水中的苯甲酸和乙酸,并配合废水生物降解的末端处理技术,研究了20%,30%和50%磷酸三丁酯(TBP)/煤油的混合溶剂、正辛醇和甲苯萃取苯甲酸稀溶液特性,以及对工业废水处理的实验.结果表明,TBP对苯甲酸稀溶液具有良好的萃取作用,而纯溶剂体系与溶剂的极性有关,正辛醇的萃取能力与30%TBP相当;残液中的COD_Cr值由萃取剂在水中的溶解和苯甲酸自身的COD_Cr值组成,其中残液中溶剂溶解导致的COD_Cr值随其中苯甲酸浓度变化不明显,且COD_Cr值的大小为:50%TBP≈30%TBP>正辛醇>20%TBP>甲苯.针对工业废水中主要含有苯甲酸和乙酸的工况,提出了废水资源化的处理工艺流程,即首先采用甲苯进行废水中苯甲酸的回收,之后,再利用三烷基氧磷/煤油为萃取剂回收废水中的醋酸,进一步生产绿色化学品乙酸钙镁盐.     

电池生产含铅废水处理技术研究

研究针对电池生产废水含铅、含氟、含磷、高酸性的特点,采用物化加生化的混凝气浮-化学反应-曝气生物滤池的处理工艺,去除废水中的氟、铅及部分磷酸盐,同时充分吸收、吸附污水中的污染物,达到降解有机污染物、减少污水中BOD5、COD的含量,从而达到良好的处理效果,最终达标排放。     

Characteristics of contaminants in water and sediment of a constructed wetland treating piggery wastewater e uent

Constructed wetland (CW) is the preferred means of controlling water quality because of its natural treatment mechanisms and function as a secondary or tertiary treatment unit. CW is increasingly applied in Korea for secondary e uent of livestock wastewater treatment. This study was conducted to recognize the characteristics of contaminants in the accumulated sediment at the bottom soil layer and to reduce the phosphorus release from sediments of the free water surface CW for the treatment of secondary piggery wastewater e uent from a livestock wastewater treatment facility. The results revealed that the dominant phosphorus existence types at near the inlet of the CW were non-apatite phosphorus (59%) and residual phosphorus (32%) suggesting that most of the particles of the influent are made up of inorganic materials and dead cells. Sediment accumulation is important when determining the long-term maintenance requirements over the lifetime of CW. Continuous monitoring will be performed for a further assessment of the CW system and design.     

城市污水预水解对二级生化处理的影响

为考察预水解对后续二级生化处理的影响,结合无锡市城北污水处理厂实际运行情况进行了生产性试验研究。结果表明,对于工业废水占40%的城市污水而言,原水经过水解预处理后的可生化性得到提高,并且由于水解池在未满负荷运行的情况下对碳源有机物的去除率较高,对后续硝化脱氨、反硝化脱氮和除磷存在不同的影响。     

密闭环境空调系统二次污染问题研究

密闭环境空调系统存在一系列特殊的室内空气品质问题.详细介绍了密闭空间空调系统二次污染的现状、对人员健康的影响、控制措施.提出2种解决空调系统二次污染问题的思路:终点控制和起点控制.终点控制措施和起点控制措各有其优点及缺点,适用范围也不一样.潜艇、深水工作船、宇宙飞船等密闭空间空调系统要根治二次污染问题,必须起点控制和终点控制相结合,在工程实践中逐步摸索出适用的方法.     

Sensitivity evaluation of the visual,tactile, and auditory detection response task method while driving

Objectives: In this article, we evaluate the sensitivity to cognitive load of 3 versions of the Detection Response Task method (DRT), proposed in ISO Draft Standard DIS-17488.

Methods: We present a user study with 30 participants in which we compared the sensitivity to cognitive load of visual, audio, and tactile DRT in a simulated driving environment. The amount of cognitive load was manipulated with secondary n-back tasks at 2 levels of difficulty (0-back and 1-back). We also explored whether the DRT method is least sensitive to cognitive load when the stimuli and secondary task are of the same modality. For this purpose, we used 3 forms to present the n-back task stimuli: visual, audio, and tactile. Responses to the task were always vocal. The experiment was based on a between-subject design (the DRT modalities) with 2 levels of within-subject design study (modalities and difficulty of the secondary n-back tasks). The participants' primary task in the study was to drive safely, and a second priority was to answer to DRT stimuli and perform secondary tasks.

Results: The results indicate that all 3 versions of the DRT tested were sensitive to detecting the difference in cognitive load between the reference driving period and driving and engaging in the secondary tasks. Only the visual DRT discriminated between the 0-back and 1-back conditions on mean response time. Contrary to expectations, no interaction was observed between DRT modality and the stimuli modality used for presentation of the secondary tasks.

Conclusions: None of the 3 methods of presenting DRT stimuli showed a consistent advantage in sensitivity in differentiating multiple levels of cognitive load if all response times, hit rates, and secondary task performance are considered. If only response time is considered, the visual presentation of the DRT stimulus used in this study showed some advantages. In interpreting these data, it should be noted that the methods of DRT stimulus presentation varied somewhat from the currently proposed draft ISO standard and it is possible that the relative salience level of the visual DRT stimulus influenced the findings. It is further suggested that more than 2 levels of difficulty of the n-back task should be considered for further investigation of the relative sensitivity of different DRT stimuli modalities. Parameters that indicate change in cognitive load (response time, hit rate, task performance) should be analyzed together in assessing the overall impact on the driver and not individually, in order to obtain a fuller insight of the assessed cognitive load.     

催化氧化法处理焦化污水生化出水的中试研究

采用ClO_2三相催化氧化工艺对焦化污水二沉池出水的处理进行了中试研究,考察了进水量、供气量、加药量等参数对焦化污水COD处理效果的影响,得出的最佳工艺条件为:进水量0.2 m~3/h,有效催化剂用量0.5 m~3,供气量10 m~3/h,盐酸投加量60 m L/h,氯酸钠投加量30 m L/h。最佳工艺条件下,平均出水COD为44 mg/L,平均去除率为80.3%,能达到国家一级排放标准。     

Denitrification potential enhancement by addition of external carbon sources in a pre-denitrification process

The aim of this study is to investigate the denitrification potential enhancement by addition of external carbon sources and to estimate the denitrification potential for the predenitrification system using nitrate utilization rate （NUR） batch tests. It is shown that the denitrification potential can be substantially increased with the addition of three external carbon sources, i.e. methanol, ethanol, and acetate, and the denitrification rates of ethanol, acetate, and methanol reached up to 9.6, 12, and 3.2 mgN/（g VSS.h）, respectively, while that of starch wastewater was only 0.74 mgN/（g VSS,h）. By comparison, ethanol was found to be the best external carbon source. NUR batch tests with starch wastewater and waste ethanol were carried out. The denitfification potential increased from 5.6 to 16.5 mg NO3-N/L owing to waste ethanol addition. By means of NUR tests, the wastewater characteristics and kinetic parameters can be estimated, which are used to determine the denitrification potential of wastewater, to calculate the denitrification potential of the plant and to predict the nitrate effluent quality, as well as provide information for developing carbon dosage control strategy.     

棉纺织企业火灾成因及消防管理对策研究

棉纺织企业存在大量的易燃可燃物质,火灾危险性大,极易引发火灾事故,且火灾蔓延途径多、燃烧速度快,易造成严重后果。该文根据棉纺织企业生产的特点,从人—机—环境系统的角度,从"人的不安全行为"、"物的不安全状态"和"环境的不安全条件"三个方面分析了棉纺织企业火灾的成因,有针对性从六个方面提出了消防安全管理对策,对提高企业的消防安全管理水平,增强其经济效益和社会效益具有重要的意义。