一株乙醇利用菌的分离及其在乙醇含量测定中的应用

从山西清徐农用沼气池中分离得到一株能以乙醇为唯一碳源和能源生长的菌株ME45,通过生理生化特征及16S rDNA序列分析,将ME45鉴定为嗜有机甲基杆菌(Methylobacterium organophilium).依据ME45能在有氧条件下利用乙醇的特性,因此以固定化细胞和溶氧仪组成测定系统测定了不同含量乙醇的响应时间以及溶氧变化与乙醇含量的关系.结果表明,乙醇含量在0.02%～2%(V/V)范围内,响应时间小于25 min,溶氧消耗量同乙醇含量呈函数关系,拟合系数(R2)为0.9947.干扰实验结果表明,该测定体系具有较强的选择性,待测乙醇样品中其它醇类物质含量不高于乙醇含量5倍对乙醇测定无干扰.以95%乙醇为样品进行多次测定,测定平均值为91.8%,RSD为3.5%,表明该反应体系重现性良好.本研究为进一步研究乙醇微生物传感器奠定了基础.图7表1参15     

Assessment of surface water quality using multivariate statistical techniques in red soil hilly region: a case study of Xiangjiang watershed, China

In the study, multivariate statistical methods including factor, principal component and cluster analysis were applied to analyze surface water quality data sets obtained from Xiangjiang watershed, and generated during 7 years (1994-2000) monitoring of 12 parameters at 34 different profiles. Hierarchical cluster analysis grouped 34 sampling sites into three clusters, including relatively less polluted (LP), medium polluted (MP) and highly polluted (HP) sites, and based on the similarity of water quality characteristics, the watershed was divided into three zones. Factor analysis/principal component analysis, applied to analyze the data sets of the three different groups obtained from cluster analysis, resulted in four latent factors accounting for 71.62%, 71.77% and 72.01% of the total variance in water quality data sets of LP, MP and HP areas, respectively. The PCs obtained from factor analysis indicate that the parameters for water quality variations are mainly related to dissolve heavy metals. Thus, these methods are believed to be valuable to help water resources managers understand complex nature of water quality issues and determine the priorities to improve water quality.     

环境影响综合评价的灰色关联分析方法

设想理想环境系统,以实际环境系统及其子系统与理想环境系统关系密切的程度作为指标,通过灰色关联分析的具体手段提出了一个解决问题的新方法一环境影响综合评价的灰色关联分析方法,并在东江水电工程的环境影响评价中得到应用。结果是建库前环境（序列）与理想环境（序列）的关联度r₁₀小于建库后的环境（序列）与理想环境（序列）的关联度r₁₀,工程对环境影响的定量为r₂₀r₁₀＝0.122,即工程使环境总体向理想环境发展了12.2%。如何确定理想环境序列是该方法的关键。     

农业废物好氧堆肥过程因子对细菌群落结构的影响

采用聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)技术研究了农业废物堆肥过程中细菌种群随时间的变化.同时,应用Quantity One2.0和Canoco4.5软件对获得的堆肥细菌种群数据与堆肥过程因子:环境温度、堆体温度、pH、含水率、水溶性有机碳(WSC)、C/N、水溶性氨氮(NH4+-N)和硝氮(NO3--N)进行冗余分析,并做出样点、种群与堆肥过程因子的二维排序图.结果表明,细菌群落(样点)以堆肥过程因子为梯度大体可划分为升温期(1～2d)、高温期(3～11d)、降温期(12～18d)和腐熟期(19～36d)4个阶段,每一阶段均有对应种群存在.不同的堆肥过程因子对细菌种群的影响大小依次为:NO3--N堆体温度WSCC/NNH4+-N含水率pH环境温度,其中,堆体温度、WSC、NO3--N、NH4+-N对细菌种群的影响极显著(p0.01),C/N、pH对细菌种群的影响显著(p0.05),含水率、环境温度对细菌种群的影响不显著.     

一株毒死蜱降解菌的分离鉴定及降解性能研究

从农药厂废水处理池污泥中分离到一株对毒死蜱有较强降解能力的菌株CH3,通过生理生化试验初步将该菌鉴定为哈夫尼菌属(Hafnia sp.)。CH3能以毒死蜱为唯一碳源生长,在温度为30℃,pH为7.0,毒死蜱初始浓度为200 mg/L的条件下,历时6 d,毒死蜱的降解率可达78.5%。菌株最适生长温度为37℃,最适pH值为7.0,最适降解浓度为200 mg/L。对碳、氮源利用广泛,最佳碳源为蔗糖和葡萄糖,对氮源选择性不高,在无机氮源和有机氮源中均能较好地生长。     

围场县农田典型药物和个人护理品污染特征与生态风险预评价

利用超声萃取-固相萃取-高效液相色谱/串联质谱(LC-MS/MS)技术,对围场县全县农田中5个大类(磺胺类、四环素类、氟喹诺酮类、大环内酯类以及其他类)25种典型药物和个人护理品(PPCPs)的污染水平进行了调查,并采用风险熵法对其进行生态风险预评价。结果表明:有23种目标PPCPs被检出,不同目标物检出率差异显著,检出含量范围为0.38~6.50μg·kg-1,单种污染物最高检出浓度为101.9μg·kg-1(磺胺甲恶唑)。以目标物划分,分别有7种和5种被检出物质达到生态高风险和中等风险水平;以采样区域划分,41个土壤点位中分别有17个和12个达到生态高风险和中等风险水平。畜用PPCPs是围场农田中PPCPs污染物的主要来源,兽药滥用、粪便自然堆沤等传统农耕模式有造成农田土壤中PPCPs累积的趋势,因此需严控PPCPs污染源头,并推进畜禽粪便安全的资源化利用,以减缓农田土壤中由于PPCPs污染带来的潜在生态风险,保障围场地区生态环境功能、农田环境质量以及农产品安全品质。     

Generation and management of waste electric vehicle batteries in China

With the increasing adoption of EVs (electric vehicles), a large number of waste EV LIBs (electric vehicle lithium-ion batteries) were generated in China. Statistics showed generation of waste EV LIBs in 2016 reached approximately 10,000 tons, and the amount of them would be growing rapidly in the future. In view of the deleterious effects of waste EV LIBs on the environment and the valuable energy storage capacity or materials that can be reused in them, China has started emphasizing the management, reuse, and recycling of them. This paper presented the generation trend of waste EV LIBs and focused on interrelated management development and experience in China. Based on the situation of waste EV LIBs management in China, existing problems were analyzed and summarized. Some recommendations were made for decision-making organs to use as valuable references to improve the management of waste EV LIBs and promote the sustainable development of EVs.     

Removal of malachite green dye from wastewater by different organic acid-modified natural adsorbent: kinetics,equilibriums, mechanisms,practical application,and disposal of dye-loaded adsorbent

Natural adsorbent (Cinnamomum camphora sawdust) modified by organic acid (oxalic acid, citric acid, and tartaric acid) was investigated as a potential adsorbent for the removal of hazardous malachite green (MG) dye in aqueous media in a batch process. The extent of MG adsorption onto modified sawdust increased with increasing organic acid concentrations, pH, contact time, and temperature but decreased with increasing adsorbent dosage and ionic strength. Kinetic study indicated that the pseudo-second-order kinetic model could best describe the adsorption kinetics of MG. Equilibrium data were found to fit well with the Langmuir model, and the maximum adsorption capacity of the three kinds of organic acid-modified sawdust was 280.3, 222.8, and 157.5 mg/g, respectively. Thermodynamic parameters suggested that the sorption of MG was an endothermic process. The adsorption mechanism, the application of adsorbents in practical wastewater, the prediction of single-stage batch adsorption system, and the disposal of depleted adsorbents were also discussed.