Removal of odors and VOCs in municipal solid waste comprehensive treatment plants using a novel three-stage integrated biofilter: Performance and bioaerosol emissions

• TSIBF was composed of ABRS, FRS and HBRS. • THIBF can effectively remove various odors, VOCs and bioaerosols. • Different reaction segments in TSIBF can remove different types of odors and VOCs. • TSIBF can reduce the emission of bioaerosols through enhanced interception. A novel three-stage integrated biofilter (TSIBF) composed of acidophilic bacteria reaction segment (ABRS), fungal reaction segment (FRS) and heterotrophic bacteria reaction segment (HBRS) was constructed for the treatment of odors and volatile organic compounds (VOCs)from municipal solid waste (MSW) comprehensive treatment plants. The performance, counts of predominant microorganisms, and bioaerosol emissions of a full-scale TSIBF system were studied. High and stable removal efficiencies of hydrogen sulfide, ammonia and VOCs could be achieved with the TSIBF system, and the emissions of culturable heterotrophic bacteria, fungi and acidophilic sulfur bacteria were relatively low. The removal efficiencies of different odors and VOCs, emissions of culturable microorganisms, and types of predominant microorganisms were different in the ABRS, FRS and HBRS due to the differences in reaction conditions and mass transfer in each segment. The emissions of bioaerosols from the TSIBF depended on the capture of microorganisms and their volatilization from the packing. The rational segmentation, filling of high-density packings and the accumulation of the predominant functional microorganisms in each segment enhanced the capture effect of the bioaerosols, thus reducing the emissions of microorganisms from the bioreactor.     

模糊控制理论在煤矿通风安全自动化系统中的应用

由于煤矿通风系统的独特性和复杂性 ,要精确地建立具有时滞及控制对象的数学模型遇到较大的困难 ,因此 ,人们寻求了一些新的解决途径。笔者基于模糊控制理论 ,并提出将其应用于煤矿通风自动化系统中 ,同时采用单片机来实现模糊控制 ,实践证明 ,此法取得良好效果 ;与常规的控制方法相比 ,模糊控制方法具有响应快、控制简单、不需建模等特点 ,适用于矿井通风自动化系统 ;笔者还讨论了调节窗模糊控制系统设计 ,系统的单片机实现及软件编制 ,并进行了实验及实验结果分析 ;最后提出了向自组织方向的深化方案。     

Estimating national-scale ground-level PM25 concentration in China using geographically weighted regression based on MODIS and MISR AOD

Taking advantage of the continuous spatial coverage, satellite-derived aerosol optical depth (AOD) products have been widely used to assess the spatial and temporal characteristics of fine particulate matter (PM2.5) on the ground and their effects on human health. However, the national-scale ground-level PM2.5 estimation is still very limited because the lack of ground PM2.5 measurements to calibrate the model in China. In this study, a national-scale geographically weighted regression (GWR) model was developed to estimate ground-level PM2.5 concentration based on satellite AODs, newly released national-wide hourly PM2.5 concentrations, and meteorological parameters. The results showed good agreements between satellite-retrieved and ground-observed PM2.5 concentration at 943 stations in China. The overall cross-validation (CV) R ² is 0.76 and root mean squared prediction error (RMSE) is 22.26 μg/m³ for MODIS-derived AOD. The MISR-derived AOD also exhibits comparable performance with a CV R ² and RMSE are 0.81 and 27.46 μg/m³, respectively. Annual PM2.5 concentrations retrieved either by MODIS or MISR AOD indicated that most of the residential community areas exceeded the new annual Chinese PM2.5 National Standard level 2. These results suggest that this approach is useful for estimating large-scale ground-level PM2.5 distributions especially for the regions without PMs monitoring sites.     

皂土对CuCl_2的吸附性能

研究了CuCl2在荷结构负电荷皂土上的吸附性能,考察了pH、无机以及有机添加剂等因素的影响,并结合IR和XRD实验结果探讨了吸附机理。研究表明,皂土对CuCl2有很强的吸附能力,其吸附动力学和吸附等温线分别符合准二级速率方程和Langmuir方程。初始pH增大,吸附量增加。无机以及有机添加剂均能能明显抑制吸附。Cu2＋在皂土上的吸附层在微观上可分为因化学键合作用而形成的内络合层和因静电作用而形成的外络合层。     

Cr(Ⅵ)在Mg-Al型类水滑石上的脱附性能研究

研究了Cr(Ⅵ)在带结构正电荷的Mg-Al型类水滑石(HTlc)上的脱附性质,考察了多种脱附剂的脱附性能,研究了脱附剂种类、浓度、pH值和脱附时间等因素的影响。实验表明,脱附平衡时间比吸附平衡时间稍长,不同的脱附剂脱附效果不一样,对同一种脱附剂来说,随着脱附剂浓度的增大,脱附量增大;随着pH值的升高,脱附量总体呈上升趋势。     

皂土对CuCl2的吸附性能

研究了CuCl2在荷结构负电荷皂土上的吸附性能,考察了pH、无机以及有机添加剂等因素的影响,并结合IR和XRD实验结果探讨了吸附机理。研究表明,皂土对CuCl2有很强的吸附能力,其吸附动力学和吸附等温线分别符合准二级速率方程和Langmuir方程。初始pH增大,吸附量增加。无机以及有机添加剂均能能明显抑制吸附。Cu2+在皂土上的吸附层在微观上可分为因化学键合作用而形成的内络合层和因静电作用而形成的外络合层。     

Global gene expression and Ingenuity biological functions analysis on PCBs 153 and 138 induced human PBMC in vitro reveals differential mode(s) of action in developing toxicities

Several reports have indicated that low level of polychlorinated biphenyl (PCB) exposure can adversely affect a multitude of physiological disorders and diseases in in vitro, in vivo, and as reported in epidemiological studies. This investigation is focused on the possible contribution of two most prevalent PCB congeners in vitro in developing toxicities. We used PCBs 138 and 153 at the human equivalence level as model agents to test their specificity in developing toxicities. We chose a global approach using oligonucleotide microarray technology to investigate modulated gene expression for biological effects, upon exposure of PCBs, followed by Ingenuity Pathway Analysis (IPA), to understand the underlying consequence in developing disease and disorders. We performed in vitro studies with human peripheral blood mononuclear cells (PBMC), where PBMC cells were exposed to respective PCBs for 48 h. Overall, our observation on gene expression indicated that PCB produces a unique signature affecting different pathways, specific for each congener. While analyzing these data through IPA, the prominent and interesting disease and disorders were neurological disease, cancer, cardiovascular disease, respiratory disease, as well as endocrine system disorders, genetic disorders, and reproductive system disease. They showed strong resemblances with in vitro, in vivo, and in the epidemiological studies. A distinct difference was observed in renal and urological diseases, organisimal injury and abnormalities, dental disease, ophthalmic disease, and psychological disorders, which are only revealed by PCB 138 exposure, but not in PCB 153. The present study emphasizes the challenges of global gene expression in vitro and was correlated with the results of exposed human population. The microarray results give a molecular mechanistic insight and functional effects, following PCB exposure. The extent of changes in genes related to several possible mode(s) of action highlights the changes in cellular functions and signaling pathways that play major roles. In addition to understanding the pathways related to mode of action for chemicals, these data could lead to the identification of genomic signatures that could be used for screening of chemicals for their potential to cause disease and developmental disorders.     

遵化地质灾害发育特征及其防治措施

为了查明遵化市地质灾害分布规律和发生机制,通过野外实际调查和搜集相关资料等方法,对辖区内各种地质灾害进行了细致的分析和研究,阐述了产生地质灾害的地质条件和诱发因素,并对今后地质灾害的发展趋势做了可靠性的预测,对地质灾害防治提出建设性意见。遵化市地质灾害以地面塌陷和泥石流危害最大,其防治措施应以预防为主,加强监管力度,并积极做好工程防治工作。     

不同碳源对活性污泥反硝化能力的影响研究

针对城镇污水处理中碳源不足影响系统脱氮能力的问题,分别以乙酸钠、葡萄糖作为外源性碳源,考察其对活性污泥反硝化脱氮能力的影响。研究结果表明:在碳源投加量分别为50,100,200 mg/L条件下,单位(g)NO-3-N去除增量所需乙酸钠/葡萄糖的投加量分别为8.24 g/49.02g、9.62g/22.57g、—/21.07g。乙酸钠可用作城镇污水脱氮除磷过程中的高效外源性碳源,但从污水处理运行经济性来看,需根据系统实际需去除NO-3-N的量,合理确定碳源投加量。