不同来源污泥混燃特性及其综合燃烧性能评价

采集了广州两种生活污水污泥、两种工业污泥(印染污泥和造纸污泥),利用热重法对这4种不同来源的单一干污泥及混合污泥在不同条件下进行实验研究,同时计算了试样的4个燃烧特性指数,获得了污泥燃烧的动力学参数.实验结果表明,各污泥燃烧阶段主要分为水分析出、挥发分析出、固定碳的燃烧和无机盐类挥发分解4个阶段,其中挥发分的析出和燃烧制约着污泥燃烧整个过程.市政污泥S1与其他类污泥混烧过程中,各污泥有较明显的交互作用,其中市政污泥S1与其他3种污泥按照1∶1质量比混合后,其挥发特性指数D提高较明显,而综合燃烧特性指数S改变不明显.两种市政污泥8∶2质量比混合后,其混合样燃烧性能明显提高,其中综合燃烧指数提高接近2倍.采用积分法(Coats-Redfern方程)计算得到各燃烧阶段反应的机理方程及相应的活化能参数,发现各试样燃烧反应级数不尽相同,其中市政污泥S1与其他污泥混合后活化能E普遍降低,与样品S2混燃的活化能降低最多,对燃烧最有利.     

磷浓度对海洋小球藻叶绿素荧光及生长的影响

海水富营养化影响微藻生长,引起海洋初级生产力变化.以海洋小球藻(Chlorella sp.)为研究对象,研究不同磷浓度对其叶绿素荧光、细胞密度和色素含量变化的影响,以期找到海洋小球藻最适生长的磷浓度,为富营养条件下微藻生长的研究提供基础资料.结果表明,在培养温度为(22±1) ℃、光照强度为4 000 lx、光暗比为12 h:12 h条件下,不同磷浓度对海洋小球藻叶绿素荧光、细胞密度及色素含量影响显著,最大光能转化效率(Fv/Fm)、潜在活性(Fv/Fo)、实际光能转化效率(ΦPSⅡ)和电子传递速率(ETR)均呈先升后降的趋势,3.62 μmol/L处理组显著低于其他各组,434.52 μmol/L处理组一直处在较高水平.说明海洋小球藻的光合作用对高磷的适应范围较广,但对低磷浓度培养反应敏感.非光化学淬灭(qN)的值,3.62 μmol/L处理组高于其他各组.从细胞密度和色素含量的变化可以看出,36.21 μmol/L处理组最高,434.52、3.62 μmol/L处理组均低于36.21 μmol/L处理组.海洋小球藻生长的最适磷摩尔浓度为36.21 μmol/L.     

多视角下东北地区城市碳排放责任核算与分布特征研究

城市作为经济发展和人口聚集的中心,已经成为全球应对气候变化的核心区域,核算碳排放责任并分析其分布特征对于制定城市低碳发展路径至关重要。东北地区作为我国的老工业基地,其“能源结构偏煤,产业结构偏重”的区域发展特征严重制约了东北地区的减排进程,开展碳排放责任研究有助于引导东北地区城市低碳发展。本研究分别从“生产者责任原则”“消费者责任原则”“供应者责任原则”三个视角构建碳排放责任核算模型,计算了东北地区36个城市的碳排放,并分析城市碳排放的差异性分布特征。研究结果显示,不同类型的城市在多种责任原则下的碳排放存在差异,碳排放的分布特征与城市的资源禀赋、产业结构和经济发展水平相关。本研究将为东北地区城市的碳排放责任分配提供理论依据和数据支持,并为其他城市的节能减排提供参考。     

Distribution of polybrominated diphenyl ethers in the surface sediments of the Taihu Lake, China

Twenty-eight sediment samples were collected from the Taihu Lake and analyzed to acquire information about the levels, distribution, possible sources, time trend and inventory of polybrominated diphenyl ethers (PBDEs) in the Taihu Lake. Our results showed that the most abundant BDE congeners in surface sediments were BDE-47, 99 and 209, with a median value of 0.124, 0.279, and 22.72 ng(gdw)(-1), respectively. The levels of BDE-209 in our samples were much higher relative to those of the other BDE congeners and made up more than 80% of the PBDEs levels in almost all samples. Disregarding BDE-209, among the seven PBDEs (BDE-28, 47, 99, 100, 153, 154, 183) more concerned, the most abundant ones were BDE-47 and 99, which contributed 44.65% (ranged from 29.02% to 73.11%), 24.24% (ranged from 2.27% to 39.66%) to ∑(7)PBDEs, respectively. The correlation between PBDE and TOC was poor, indicating that PBDEs concentrations in sediments of the Taihu Lake were controlled not only by TOC contents, but also by a combined effect of transport, mixing, depositional mechanisms associated with PBDEs, uncontaminated sediments, or fresh input of PBDEs. As expected, the time trend of PBDEs concentration in surface sediment from Taihu Lake were increasing, and the inventory of ∑(25)PBDEs and BDE-209 were estimated to be 3668 kg and 26296 kg.     

不同基质体系中白腐菌对喹啉和吲哚的降解

采用单基质及混合基质体系,探讨了白腐菌Pleurotus ostreatusBP对氮杂环化合物的降解规律．结果表明,在弱酸性环境下,白腐菌能有效降解喹啉和吲哚．单基质体系中,喹啉的降解率15d内能达到89．48％,98．17％的吲哚6d内被降解;混合基质体系中,基质（喹啉、吡啶、苯酚及氨氮）的加入能促进白腐菌对吲哚的降解,但（吲哚、吡啶、苯酚及氨氮）却抑制了白腐菌对喹啉的降解．不同基质体系中,白腐菌对喹啉和吲哚的降解分别遵循零级和一级反应动力学．相对单基质而言,混合基质的存在对白腐菌生物学特性产生明显影响,可缩短生长周期,提高生长速率和漆酶活性．漆酶存吲哚的降解中起着重要的作用,但不能完全决定喹啉的降解．图5表2参14     

Have driving restrictions reduced air pollution: evidence from prefecture-level cities of China

Environmental Science and Pollution Research - With rapid economic development, air pollution became a serious problem in China. Vehicle’s exhaust emissions are among the main sources of air...     

Linear Diamides Derivative-Nucleated Biodegradable Poly(ethylene succinate) Polyester: Crystallization Kinetics and Aggregated Structure Manipulated by Hydrogen Bond Interaction

Journal of Polymers and the Environment - A linear diamides derivative (TMC300) as a nucleating agent (NA) was incorporated into biodegradable poly(ethylene succinate) (PES) to investigate effect...     

Adsorption characteristics of oxytetracycline by different fractions of organic matter in sedimentary soil

Environmental Science and Pollution Research - Sedimentary soil was selected as the original sample (SOS). The adsorption fractions were obtained by the removal of dissolved organic matter (SRDOM),...     

安全社区建设与基层安全风险治理

社会结构转型和快速发展要求基层作为风险应对主体完善风险治理体系。本文介绍了安全社区运行机制及建设绩效与经验,从“四个转变”阐述了安全社区建设对完善基层安全风险治理体系的促进作用。安全社区蕴含的风险治理理念和机制模式,对我国基层安全风险治理机制建设具有借鉴意义。     

激光类全新耗材和再生耗材对环境影响的生命周期评价

以激光类打印耗材——TN350为例,应用生命周期评价方法,对全新TN350和再生TN350进行生命周期资源消耗与污染物排放清单分析,在此基础上进行生命周期环境影响评价。重点考虑6种环境影响类型：全球变暖、酸化、富营养化、光化学臭氧、固体废弃物、工业烟尘和粉尘。结果表明,相对于全新TN350,再生TN350的原油消耗量削...