糕点行业废水处理技术剖析与工程实践

概述了我国糕点行业废水及其处理技术现状,介绍了以"改进型ABR+复合生物反应器"组合工艺为主体的糕点行业废水处理实例,工程实践表明用该组合工艺处理糕点废水可获得良好的效果。     

振动试验数据管理系统概述

随着近些年振动试验技术的快速发展,对于振动试验数据的保存、管理和统计提出了更高的要求。鉴于此,附属于试验室信息管理系统的振动试验数据管理系统作为振动试验有效的管理工具,必然会成为提升试验室振动试验能力、规范试验技术的有效工具。     

建立以人群健康为核心的国家污染防控体系——以“血铅事件”为例

环境健康事件的频发反映了我国污染防控体系的不足。以"血铅事件"为例,综述了我国铅污染管理状况,分析了我国铅环境健康防治现状,并提出了由生产排放达标为核心的国家污染防控体系向以人群健康为核心的国家污染防控体系转变的环境战略与政策管理措施。     

乌鲁木齐市大气污染防治政策变迁与展望

乌鲁木齐市大气污染治理工程已走过10多年的历程,从1998-2003年第一轮“蓝天工程”,2004-2008年第二轮“蓝天工程”,到2009年提出用4到5年时间使乌鲁木齐大气污染治理取得明显成效的战略目标.从禁原煤散烧、集中供热、洁净煤技术到制定规划、严格标准、节能减排、加强监管到坚决搬迁污染企业、决心调整能源结构、煤改气、煤改电的治理政策着重点的变迁,反映出对乌鲁木齐市大气污染治理认识不断深化,制定目标更加客观、务实.这期间乌鲁木齐市户籍人口从189万增长到273万,国民生产总值从230多亿增加到1000多亿,原煤耗量从520多万t增加到1370多万t.大气环境质量逐步改善,2008年、2009年、2010年、2011年好于2级天数达到261d、262d、266d、276d.本文对乌鲁木齐市实施蓝天工程以来采取的政策措施进行梳理分析,进一步认识乌鲁木齐市大气污染治理政策措施的调整变化历程及实施中存在问题和经验.     

垃圾渗滤液发酵产氢和产甲烷特性研究

以实际垃圾渗滤液作为厌氧发酵基质,研究了初始pH为7.0、中温(37℃)条件下的发酵产氢、产甲烷特性。结果表明,利用垃圾渗滤液作为基质发酵产氢或甲烷时,氢气的最大累积产量为24.33mL(以每克COD计,下同),甲烷的最大累积产量为91.59mL,产氢发酵在初期存在明显的迟滞期,但是产甲烷发酵不存在明显迟滞期;产氢发酵的液相末端产物中含有大量的挥发性有机酸和乙醇,乙醇、乙酸、丁酸质量浓度分别为487.23、1 175.21、1 225.78mg/L,相比产氢发酵,产甲烷发酵的液相末端产物中乙醇、乙酸、丁酸质量浓度均较低,分别为256.38、106.73、107.42mg/L;产甲烷发酵的最终pH是6.32,接近中性,而产氢发酵的最终pH为4.21,呈明显酸性;产甲烷发酵对COD的去除率(41.78%)高于产氢发酵对COD的去除率(32.14%),可能是产氢发酵液相末端产物中的乙酸能被产甲烷菌利用,而被进一步降解。     

Carbonyl emissions from vehicular exhausts sources in Hong Kong

Vehicular emission (VE) is one of the important anthropogenic sources for airborne carbonyls in urban area. Six types of VE-dominated samples were collected at representative locations in Hong Kong where polluted by a particular fueled type of vehicles, including (i) a gas refilling taxis station (liquefied petroleum gas [LPG] emission); (ii) a light-duty passenger car park (gasoline emission); (iii) a minibus station (diesel emission); (iv) a single-deck-bus depot (diesel emission); (v) a double-deck-bus depot (diesel emission); and (vi) a whole-food market entrance for light- and heavy-duty vehicles (diesel emission). A total of 15 carbonyls in the samples were quantified. Formaldehyde was the most abundant carbonyl among the VE-dominated samples, and its contribution to the total quantified amount on a molar basis ranged from 54.8% to 60.8%. Acetaldehyde and acetone were the next two abundant carbonyls. The carbonyls were quantified at three roadside locations in Hong Kong. The highest concentrations of formaldehyde and acetaldehyde, 22.7 +/- 8.4 and 6.0 +/- 2.8 microg/m3, respectively, were determined in the samples collected at a main transportation gate for goods between Hong Kong and Mainland China. The total quantified carbonyl concentration, 37.9 +/- 9.3 microg/m3, was the highest at an entrance of a cross-harbor tunnel in downtown area. The theoretical carbonyls compositions of the three roadside locations were estimated according to the VE-dominated sample profiles and the statistics on vehicle numbers and types during the sampling period. The measured compositions of formaldehyde were much higher than the theoretical compositions in summer, demonstrating that photochemical reactions significantly contributed to the formaldehyde production in the roadsides.     

脂肽类生物表面活性剂液体发酵条件的响应面优化

通过Plackett-Burman和Box-Behnken实验对解淀粉芽孢杆菌XZ-173液体发酵生产表面活性素进行了响应面优化研究。首先使用Plackett-Burman实验对影响表面活性素产量的17个因素进行显著性筛选,结果表明,MnSO4、CuSO4、温度和转速为显著性因素。再运用Box-Behnken实验对这4个显著因素的取值进一步优化,得到各因素优化后的数值分别为4.4 mg/L(MnSO4)、0.18 mg/L(CuSO4)、29℃(温度)和163 r/min(转速)。响应面分析结果表明:该菌株产生表面活性素的最佳培养基为:葡萄糖15 g/L,蛋白胨5 g/L,L-谷氨酸钠6 g/L,KH2PO40.8 g/L,MgSO40.4 g/L,KCl 0.4 g/L,酵母提取物3 g/L,L-苯丙氨酸2.5 mg/L,MnSO44.4 mg/L,CuSO40.18 mg/L,FeSO40.12 mg/L;最适培养条件:pH 7.5,温度29℃,转速163 r/min,接种量5%,装液量50 mL/250 mL,摇床培养36 h。在优化后的条件下,表面活性素实际产量为336 mg/L,实际实验结果与模型预测结果相一致。表面活性素采用HPLC技术分离,发现其在浓度仅为50 mg/L时EI24就可达到70%以上,反映了表面活性素优异的乳化活性以及广阔的应用前景。     

农户对高产农业技术扩散的生态环境影响感知实证

农民生态环境感知对促进农民自觉环境保护行为和农村两型社会建设具有重要作用。通过对湖南省洞庭湖湿地水稻主产区6个乡镇的调查,将农户生态影响感知具体化为土壤、水源、身体健康和水稻4个方面的感知,借助定量分析建立了农户综合环境感知指数,研究农民对以化学农业为代表的高产农业技术扩散的生态环境影响感知,并运用Tobit模型探讨了影响农户生态影响感知的主要因素。结果表明:农民已经意识到以石化农业为代表的高产农业技术扩散带来的不利影响,尽管他们的意识还只限于一些看得见的因素如土壤肥力、捕鱼量和健康问题,对于看不见的影响的感知还很薄弱。以化学农业为代表的高产农业技术采用的水平和持续时间直接决定了人们对于不利影响的感知。提高收入水平与教育水平、强化农业技术推广能提升农民生态环境感知,而农田水利基础设施建设和土壤肥力对农户环境感知有复杂的影响关系。     

重大水利工程项目社会风险的牛鞭效应

重大水利工程在有效利用自然资源的同时,也将带来巨大的社会风险,且这种风险在传递过程中不断被放大扭曲,具有明显的牛鞭效应。本文在构建重大水利工程项目社会风险链模型基础上,具体分析了牛鞭效应的产生原因,并定量刻画了社会风险牛鞭效应的削弱机制。研究表明,水利工程项目信息尤其是隐性信息在施工方和当地民众之间传递的不及时或不准确,将导致社会风险被大幅放大,并形成牛鞭效应。牛鞭效应的具体大小主要取决于两方面,一方面是水利工程项目直接影响的利益受损当地民众比例,另一方面是社会风险传染率与退出率的比值。针对前者,除了设计良好的补偿机制来弥补具体的、可衡量的利益损失外,还须通过建立失地农民的社保体系来维护如地缘业缘消失带来的无形损失;针对后者,可以在政府各部门、施工方和民众之间建立良好的信息共享系统,把单向沟通改变为多向沟通,把治理模式从"政府治理"改变为"政府—民众共治",从而促进社会的和谐发展。     

Variation in Vegetation Structure and Soil Properties, and the Relation Between Understory Plants and Environmental Variables Under Different Phyllostachys pubescens Forests in Southeastern China

Biodiversity maintenance and soil improvement are key sustainable forestry objectives. Research on the effects of bamboo forest management on plant diversity and soil properties are therefore necessary in bamboo-growing regions, such as southeastern China’s Shunchang County, that have not been studied from this perspective. We analyzed the effects of different Phyllostachys pubescens proportions in managed forests on vegetation structure and soil properties using pure Cunninghamia lanceolata forests as a contrast, and analyzed the relation between understory plants and environmental variables (i.e., topography, stand and soil characteristics) by canonical correspondence analysis (CCA). The forest with 80% P. pubescens and 20% hardwoods (such as Phoebe bournei, Jatropha curcas, Schima superba) maintained the highest plant diversity and best soil properties, with significantly higher plant diversity than the C. lanceolata forest, and better soil physicochemical and biological properties. The distribution of understory plants is highly related to environmental factors. Silvicultural disturbance strongly influenced the ability of different bamboo forests to maintain biodiversity and soil quality under extensive management, and the forest responses to management were consistent with the intermediate-disturbance hypothesis (i.e., diversity and soil properties were best at intermediate disturbance levels). Our results suggest that biodiversity maintenance and soil improvement are important management goals for sustainable bamboo management. To achieve those objectives, managers should balance the inputs and outputs of nutrients and protect understory plants by using appropriate fertilizer (e.g., organic fertilizer), adjusting stand structure, modifying utilization model and the harvest time, and controlling the intensity of culms and shoots harvests.