电除尘器中水雾雾化特性及对除尘性能的影响

湿式电除尘器将水雾除尘与电除尘技术相结合,可以有效地对细颗粒物进行收集,抑制了二次扬尘的发生。通过研究电除尘器喷淋系统的雾化特性,以及不同供水压力对水雾荷电的影响,并测得其分级效率。研究结果表明:在供水压力为0.4 MPa时,湿式电除尘器的除尘效率大于99.5%;在喷雾粒径为100μm时,对10μm以下的细颗粒物除尘效率大于92%。通过分析,为湿式除尘器喷淋系统设计提供了依据。     

Simultaneous preconcentration of cadmium and lead in water samples with silica gel and determination by flame atomic absorption spectrometry

A new method that utilizes pretreated silica gel as an adsorbent has been developed for simultaneous preconcentration of trace Cd(II) and Pb(II) prior to the measurement by flame atomic absorption spectrometry. The effects of pH, the shaking time, the elution condition and the coexisting ions on the separation/preconcentration conditions of analytes were investigated. Under optimized conditions, the static adsorption capacity of Cd(II) and Pb(II) were 45.5 and 27.1mg/g, the relative standard deviations were 3.2% and 1.7% (for n = 11), and the limits of detection obtained were 4.25 and 0.60 ng/mL, respectively. The method was validated by analyzing the certified reference materials GBW 07304a (stream sediment) and successfully applied to the analysis of various treated wastewater samples with satisfactory results.     

Research on the evolvement of morphology of coking coal during the coking process

The evolvement of morphology and structure of the coal with different metamorphic degrees during coking process in the vertical furnace was investigated by infrared Image detector. Moreover, the temperature distribution in the radial direction and the crack formation were also studied in heating process. The results show that the amount of crack and the shrinkage level of char decrease with the coal rank rising. In addition, the initial temperature of crack formation for char increases with the coal rank rising.     

生活垃圾中废塑料分选回收技术概述

近年来,废塑料在城市生活垃圾中占有相当大的比例,其含量正呈逐年上涨的趋势,因此对塑料进行分选和资源化利用势在必行。塑料分选技术是摆在我们中间的一项难题,目前生活垃圾废塑料的分选技术五花八门．由于在全国各地废塑料在垃圾中的还水量等因素的影响,现实中能实现废塑料的分选还不成熟。因此,研究一套适合废塑料的分选技术迫在眉睫。     

饭馆、餐厅油烟机、风机噪声扰民实例研究

随着城市化进程的加快,人民生活水平的提高,饭馆、餐厅的油烟机、风机等设施噪声扰民的事件频发。本文通过对饭馆、餐厅一条街噪声扰民事件进行原因分析、采取防治措施、治理效果验证,提出了饭馆、餐厅等社会娱乐服务场的噪声防治措施,对提高人民生活水平、减少居民投诉、促进社会和谐具有建设性意义。     

汽车尾气污染及其净化处理技术

本文详细阐述了汽车尾气的有害成份及其对人类健康的危害。为此 ,应该采取净化处理措施 ,减少或者消除有害气体的产生 ,为大气环境洁净而创造条件。     

铜铁矿井下采掘工程的环境影响及生态保护

对铜铁矿井下采掘工程产生的环境影响进行了分析，外排井下涌水下的铜可对鱼类养殖业水体的地表水质带来不利影响，采用帷幕注浆堵水工艺可防止大面积地表塌陷的发生，对难以避免的局部，小规模塌陷提出了生态安全的预警措施。     

利用合成氨二段转化气联产甲醇技术的可行性分析

通过对国内外不同甲醇合成生产工艺技术概况及能耗指标的分析，探讨合成氨化肥企业利用现有工艺技术进行改造的可行性，以提高企业对市场的适应性。     

Controlling cyanobacterial blooms by managing nutrient ratio and limitation in a large hypereutrophic lake: Lake Taihu, China

Excessive nitrogen (N) and phosphorus (P) loading of aquatic ecosystems is a leading cause of eutrophication and harmful algal blooms worldwide, and reducing nutrient levels in water has been a primary management objective. To provide a rational protection strategy and predict future trends of eutrophication in eutrophic lakes, we need to understand the relationships between nutrient ratios and nutrient limitations. We conducted a set of outdoor bioassays at the shore of Lake Taihu. It showed that N only additions induced phytoplankton growth but adding only P did not. Combined N plus P additions promoted higher phytoplankton biomass than N only additions, which suggested that both N and P were deficient for maximum phytoplankton growth in this lake (TN:TP = 18.9). When nutrients are present at less than 7.75-13.95 mg/L TN and 0.41-0.74 mg/L TP, the deficiency of either N or P or both limits the growth of phytoplankton. N limitation then takes place when the TN:TP ratio is less than 21.5-24.7 (TDN:TDP was 34.2-44.3), and P limitation occurs above this. Therefore, according to this ratio, controlling N when N limitation exists and controlling P when P deficiency is present will prevent algal blooms effectively in the short term. But for the long term, a persistent dual nutrient (N and P) management strategy is necessary.     

Molecular diversity of arbuscular mycorrhizal fungi at a large-scale antimony mining area in southern China

Arbuscular mycorrhizal fungi (AMF) have great potential for assisting heavy metal hyperaccumulators in the remediation of contaminated soils. However, little information is available about the community composition of AMF under natural conditions in soils contaminated by antimony (Sb). The objective of this study was to investigate the characteristics of AMF molecular diversity, and to explore the effects of Sb content and soil properties on the AMF community structure in an Sb mining area. Four Sb mine spoils and one adjacent reference area were selected from around the Xikuangshan mine in southern China. The association of AMF molecular diversity and community composition with the rhizosphere soils of the dominant plant species was studied by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE). Results from all five studied sites showed that the diversity of AMF decreased with increasing Sb concentration. Principal component analysis (PCA) indicated that the AMF community structure was markedly different among these groups. Further redundancy analysis (RDA) showed that Sb contaminationwas the dominating factor influencing the AMF community structure in the Sb mine area. However, the multivariate analysis showed that, apart from the soil Sb content, extractable nitrogen content and organic matter content also attributed to AMF sequence distribution type. Some AMF sequences were only found in the highly contaminated area and these might be ideal candidates for improving phytoremediation efficiency in Sb mining regions. Gene sequencing analysis revealed that most species were affiliated with Glomus, suggesting that Glomus was the dominant AMF genus in the studied Sb mining area.