金属离子强化餐厨垃圾高温厌氧发酵产酸

以经过高温驯化的污泥作为厌氧微生物,以餐厨垃圾作为发酵基质,向发酵体系中加入不同浓度Fe2+、Mg2+和Ni2+进行单因素实验。实验结果表明:当Fe2+、Mg2+和Ni2+加入量分别为800、250和0.50 mg/L时,挥发性脂肪酸(VFA)的产量最大,分别为23.58、22.38和23.08 g/L;加入不同浓度Fe2+、Mg2+和Ni2+的厌氧发酵液相产物中丁酸含量均最高,但在一定浓度范围内随着金属离子的添加,发酵产物中丁酸所占的比例逐渐减小,乙酸所占比例逐渐增加;加入适量金属离子在一定程度上能够抑制发酵液中氨氮的溶出。     

基于环境DNA宏条形码的青岚湖自然保护区鱼类组成及分布特征

为探究在不同引物、不同参考数据库下环境DNA技术检测结果的差异,于2021年4月,采用环境DNA宏条形码技术分析了青岚湖鱼类多样性。选取16S rRNA及Cytb 2种引物,NCBI及本地数据库2种数据库,分别进行比对注释。结果表明:在青岚湖29个采样点中,共检测到7目15科43属64种鱼类,其中在16S-NCBI情形下获得4目9科19属20种鱼类,在16S-本地数据库情形下获得6目13科27属38种鱼类,在Cytb-NCBI情形下获得4目6科16属19种鱼类,在Cytb-本地数据库情形下获得2目5科15属20种鱼类。在青岚湖29个采样点中,鱼类更多地分布于湖面宽阔的中间地带(如S31附近),且南部较北部更少,鱼种的分布呈现一定的空间相似性。就研究区域而言,选择16S rRNA引物及本地数据库可以获得更全面的鱼类物种。通过与青岚湖鱼类历史数据比对发现,环境DNA技术在研究区域具有较强的适用性,如能选择适当的引物和本地数据库,可以更全面地反映研究区域的物种组成情况。     

改性丝瓜络纤维对水体日落黄的吸附特性

采用化学改性的方法将丝瓜络制备为阴离子吸附剂,并将其用于水体日落黄(SY)染料的吸附,分别考察了吸附剂的用量、日落黄染料的初始浓度(C0)、pH值、温度(K)、时间(T)5个因素对吸附效果的影响。通过模拟吸附等温曲线、吸附动力学以及热力学方程并通过比表面积(BET)和红外光谱(FTIR)分析改性丝瓜络吸附染料前后和丝瓜络改性前后的变化情况以此探究其吸附机理。结果表明,pH对吸附效果影响不明显;最大吸附量随温度升高而增大,在298 K温度时最大吸附量达到137 mg/g,是未改性丝瓜络的9.78倍。Langmuir方程拟合吸附过程描述最好,吸附类别为化学吸附。吸附过程符合伪二级动力学,是一个自发和吸热的过程。改性丝瓜络可以有效去除水体中的日落黄染料。     

我国应急管理的发展现状与未来路径分析

2003年非典过后,我国应急管理"一案三制"体系正式提出并逐步构建,随后应急管理体系得到迅速完善,但总体来看还是"摸着石头过河".十八大后,习总书记提出国家总体安全观、防范和化解重大风险等重大战略安排和制度选择;十九大以来,国家机构改革组建应急管理部、召开十九届四中全会,明确提出要实现应急管理体系和能力现代化,为应急管...     

太湖流域面源污染控制对策研究

近年来.随着点源污染得到逐步治理,面源污染已成为水体富营养化的主要污染源,本文介绍了太湖流域面源 污染的现状,分析了其构成,列举了国内外目前治理面源污染的一些措施,并就太湖流域面源污染的特点提出了一些控制 治理对策。     

我国核电发展现状浅析

核电作为一种安全的清洁能源,对于优化能源结构、减少环境污染、具有重要意义。本文介绍了我国核电的现状,从安全性、环保性、经济性几方面对核电进行分析比较,说明积极推进核电发展是我国未来电力发展的选择。     

Numerical model to quantify biogenic volatile organic compound emissions: The Pearl River Delta region as a case study

This article compiles the actual knowledge of the biogenic volatile organic compound (BVOC) emissions estimated using model methods in the Pearl River Delta (PRD) region, one of the most developed regions in China. The developed history of BVOC emission models is presented briefly and three typical emission models are introduced and compared. The results from local studies related to BVOC emissions have been summarized. Based on this analysis, it is recommended that local researchers conduct BVOC emission studies systematically, from the assessment of model inputs, to compiling regional emission inventories to quantifying the uncertainties and evaluating the model results. Beyond that, more basic researches should be conducted in the future to close the gaps in knowledge on BVOC emission mechanisms, to develop the emission models and to refine the inventory results. This paper can provide a perspective on these aspects in the broad field of research associated with BVOC emissions in the PRD region.     

有机固体废弃物堆肥的腐熟度参数及指标

腐熟度参数及其指标是评价堆肥过程及堆肥产品质量的重要尺度,本文综述了关于腐熟度的表观分析法、化学分析法、波谱分析法及植物生长分析法等４类评价方法和各种腐熟度参数及指标。     

厌氧-好氧法治理中药废水研究

厌氧—好氧法处理中药废水 ,污泥中生物相丰富 ,原生、后生动物数量多 ,污泥沉降性能优良 ,出水水质好 ,CODCr、BOD5 等指标都达到了一级排放标准。     

Applying a new method for direct collection,volume quantification and determination of N2 emission from water

The emission of N2 is important to remove excess N from lakes, ponds, and wetlands. To investigate the gas emission from water, Gao et al.(2013) developed a new method using a bubble trap device to collect gas samples from waters. However, the determination accuracy of sampling volume and gas component concentration was still debatable. In this study, the method was optimized for in situ sampling, accurate volume measurement and direct injection to a gas chromatograph for the analysis of N2 and other gases. By the optimized new method, the recovery rate for N2 was 100.28% on average; the mean coefficient of determination(R2) was 0.9997; the limit of detection was 0.02%. We further assessed the effects of the new method, bottle full of water, vs. vacuum bag and vacuum vial methods, on variations of N2 concentration as influenced by sample storage times of 1,2, 3, 5, and 7 days at constant temperature of 15°C, using indices of averaged relative peak area(%) in comparison with the averaged relative peak area of each method at 0 day.The indices of the bottle full of water method were the lowest(99.5%–108.5%) compared to the indices of vacuum bag and vacuum vial methods(119%–217%). Meanwhile, the gas chromatograph determination of other gas components(O2, CH4, and N2O) was also accurate. The new method was an alternative way to investigate N2 released from various kinds of aquatic ecosystems.