鄂尔多斯TSP和PM_(10)中有机氯农药的分布与来源

于2012年5月在内蒙古鄂尔多斯的东胜、纳林希里、棋盘井和上湾等4个采样点连续采集大气TSP和PM10样品,利用GC-MS分析了其中18种OCPs。结果表明:除了硫丹Ⅱ、硫丹Ⅰ和α-HCH未检出,β-HCH部分检出以外,其余14种OCPs均有100%检出。鄂尔多斯东胜、纳林希里、棋盘井和上湾TSP中∑OCPs浓度依次为2.63、9.85、5.09和6.22ng/m3;在PM10中为2.13、8.74、4.84和6.77ng/m3。∑OCPs中比重超过15%的有ADs、HCs和DDTs。TSP中∑OCPs浓度基本高于PM10中浓度,并且它们存在较好的正相关,相关系数r达到0.8846。污染源分析表明,纳林希里HCHs、CDs和DDTs可能均有外源输入。     

拟除虫菊酯农药的微波辅助无极汞灯下的降解机理研究

在水溶液中,以微波辅助无极汞灯(Microwave-Assisted Eletrodeless Discharge Mercury Lamp,MW-EDML)降解氯氰菊酯、甲氰菊酯和功夫菊酯等3种拟除虫菊酯农药(Synthetic pyrethroids,SPs),采用固相萃取(Solid Phase Extraction,SPE)富集后,用GC-MS鉴定降解产物,并根据降解产物重点探讨了SPs的降解机理。3种SPs的主要降解产物有6种,其降解途径有:酯键水解、氰基水解、脱羧、醚键断裂、氧化、苯环的羟基化以及与溶剂反应等。实验结果还表明:MW-EDML是个高效、简便的降解SPs类农药手段,可应用于其他有机污染物的降解过程。     

拟除虫菊酯类农药的非对映和对映异构体分离

正己烷/异丙醇为流动相的正相体系中,使用SupelcosilLC-CN氰基柱完全分离了氯氰等多种拟除虫菊酯农药的非对映异构体;使用SupelcosilLC-CN保护柱串联ChiralcelOD-H手性柱以及使用SupelcosilLC-CN氰基柱串联ChiralcelOD-H手性柱实现了氯氰等多种拟除虫菊酯类农药的对映异构体分离.流动相中异丙醇的比例对保留时间和分离度的影响较大,随着异丙醇比例的减少,保留时间和分离度逐渐增加;在0～30℃之间,柱温对手性识别能力无明显的影响;但对保留时间影响明显,随着柱温的增加,保留时间缩短.     

Microbiological risk assessment of Agios Georgios source supplies in Northwestern Greece based on faecal coliforms determination and sanitary inspection survey

The assessment of potential risks from microbiological contamination of drinking water supplies is of greatest concern to human health. The study involves the examination of water samples from Agios Georgios source that supplies the capitals, the major towns and several villages of Arta, Preveza and Lefkada prefectures, in Northwestern Greece. The study includes the sanitary inspection survey of the source and the microbiological examination of water samples on a monthly basis during the period February 1996-June 1999 except of Augusts (n=38). The microbiological risk assessment (MRA) approach of World Health Organisation (WHO) guidelines was applied to enhance the source protection. The faecal contamination of the source water was quantified using faecal coliforms (FC) as indicator bacteria. Microbiological analyses indicate that of the 38 samples analyzed the FC failure rate (positive samples) was 63.2% according to the limit set by the 98/83 directive of the European Union. The 36.8% of the source water samples was found in conformity with WHO guidelines, 42.1% of low risk, 21.1% of intermediate risk while there was not found samples of high or very high risk. Failure rates displayed a seasonal trend being greater during the winter, decreased during spring and autumn and lower during summer. This observation was explained partially by a significant positive relationship with the rainfall amount (r(Spearmann)=0.890, P=0.001). The sanitary inspection score was found 5/10 during the whole survey period that corresponds to an intermediate risk of source contamination. The color-code classification for FC contamination was found 36.8% A (blue, no risk), 42.1% B (green, low risk) and 21.1% C (yellow, intermediate risk). The previous risks were combined for the assessment of waterborne risk, which was determined as intermediate to high; therefore there is a need for high action priority. The potential remedial actions were also suggested in order to improve the source protection of such supplies.     

南水北调中线工程调水前后汉江下游水生态环境特征与响应规律识别

随着我国南水北调中线工程（简称“中线工程”）于2014年底正式通水运行,科学识别调水前后汉江下游水生态环境特征与响应规律,是国家重大水利工程优化调度的迫切管理需求.基于系统收集的2010—2017年汉江下游水文、气象、水质及水生态数据匹配资料,利用多种数据模型方法识别了中线工程调水前后汉江下游主要环境要素特征和响应规律,探索了导致河流生态退化的关键驱动因子及其贡献.结果表明:①中线工程开通后,受丹江口水库下泄流量减少的影响,汉江下游多年平均流量下降了11.5%,流量年内分配趋于不均匀,流量变幅增大,人类活动对汉江下游径流过程的影响更为显著.②调水后汉江下游ρ（TP）、ρ（TN）减小,武汉段ρ（Chla）和藻密度显著上升,汉江下游水华的发生对水文过程改变更加敏感.③基于GAM模型（广义相加模型）的相关分析,调水前后影响汉江下游藻密度变化的关键因子是流量和ρ（TP）,调水前贡献率分别为27.7%和20.5%,调水后贡献率分别为65.4%和20.5%,调水后汉江下游流量对藻密度变化的贡献率显著升高,说明上游调水引起的汉江下游流量减小对水华暴发的影响十分明显,而TP等营养盐的影响相对减弱.      

TiO2 photocatalyzed degradation of diazinon in an aqueous medium

The photocatalytic degradation of diazinon was studied over TiO₂ catalysts. The kinetics obtained demonstrated that powder titania (t_1/2 = 9.7 min) was more efficient compared to pure titania thin film catalysts (t_1/2 = 29.4 min). Mineralization of organic carbon to CO₂ after 360 min of irradiation was found to be 75% while heteroatoms (P, S, N) were mineralized into phosphate, sulfate and nitrate ions, respectively. A microtox test was performed to evaluate the toxicity of solutions treated by catalysts. Illumination of diazinon in the presence of TiO₂ gave rise to several intermediates that have been identified by means of solid phase extraction and gas chromatography-mass spectrometry, while a simple degradation pathway is proposed.     

高职高专绿色食品专业实践教学环节的内容与方法研究

实践性教学是培养高职专业人才不可缺少的重要的教学环节，实践性教学环节主要包括专业认识性实习、课程实验（实习）、专业生产实习、毕业实习四个方面。本文论述了高职高专绿色食品专业的各个实践教学环节的内容和方法。     

Growth rate effects, responses of antioxidant enzymes and metabolic fate of the herbicide Propanil in the aquatic plant Lemna minor

Propanil (3,4-dichloropropionanilide) is a selective contact pesticide, recommended for post-emergence use in rice. This herbicide may end up in surface waters and present potential risk for aquatic vascular plants. Therefore, its toxicity was evaluated on Lemna minor L., an aquatic plant regularly used for toxicological studies, during time- and concentration-dependent exposure. Toxicity assessments were based on inhibition of growth of L. minor cultures after 24 days. The obtained results showed that the growth of Lemna was affected by the herbicide. The responses of the guaiacol peroxidase (G-POD) and glutathione S-transferase (GST) involved in the xenobiotic metabolism and antioxidative system were also investigated following Propanil exposure. Our results showed that Propanil has not induced enzymatic antioxidative defenses of L. minor. Both 3,4-dichloroaniline (3,4-DCA) and 3,4-dichloroacetanilide are the major metabolites in this plant. On the contrary, only 3,4-DCA was found in culture media after 4 days. Probably, the enzymatic hydrolysis by acyl acylamidase and the acetylation by acetyl-CoA are the major pathways for these transformation products, respectively. The results of this study showed that the selected aquatic plant has the potential to accumulate and metabolize rice herbicide, like Propanil. Based on these toxicity data this herbicide should impair the establishment of non-target aquatic plants.     

The status of pesticide pollution in surface waters (rivers and lakes) of Greece. Part I. Review on occurrence and levels

This review evaluates and summarizes the results of long-term research projects, monitoring programs and published papers concerning the pollution of surface waters (rivers and lakes) of Greece by pesticides. Pesticide classes mostly detected involve herbicides used extensively in corn, cotton and rice production, organophosphorus insecticides as well as the banned organochlorines insecticides due to their persistence in the aquatic environment. The compounds most frequently detected were atrazine, simazine, alachlor, metolachlor and trifluralin of the herbicides, diazinon, parathion methyl of the insecticides and lindane, endosulfan and aldrin of the organochlorine pesticides. Rivers were found to be more polluted than lakes. The detected concentrations of most pesticides follow a seasonal variation, with maximum values occurring during the late spring and summer period followed by a decrease during winter. Nationwide, in many cases the reported concentrations ranged in low ppb levels. However, elevated concentrations were recorded in areas of high pesticide use and intense agricultural practices. Generally, similar trends and levels of pesticides were found in Greek rivers compared to pesticide contamination in other European rivers. Monitoring of the Greek water resources for pesticide residues must continue, especially in agricultural regions, because the nationwide patterns of pesticide use are constantly changing. Moreover, emphasis should be placed on degradation products not sufficiently studied so far.