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1.
黄备  邵君波  魏娜  王益鸣 《生态环境》2014,(9):1457-1462
为准确掌握东海近岸海域赤潮发生情况,深入了解东海海域赤潮发生时和未发生时的生态环境条件,根据浙江省舟山海洋生态环境监测站对东海近岸海域常年的监测结果,选定从杭州湾外侧向南到温州南麂列岛的东海近岸海域为赤潮高发区,开展生态环境研究.2014 年4 月和5 月利用专业海洋调查船,按《海洋监测规范》对东海赤潮高发海域进行了二次综合海洋生态环境调查,结果发现调查海域氮、磷营养盐含量普遍较高,4 月研究海域无机氮均值为0.406 mg·L^-1,活性磷酸盐均值0.013 mg·L^-1;5 月无机氮均值0.244 mg·L^-1,活性磷酸盐均值0.004 mg·L^-1.大多数样品无机氮超一类海水水质标准,尤其是4 月91.7%的样品超-类海水标准,5 月也有35.7%样品超-类海水标准.硝酸盐氮是无机氮的主要存在形式.2014 年5 月调查期间发生了大面积的赤潮,赤潮原因种是东海原甲藻(Prorocentrum donghaiense),细胞密度平均在107/L 以上.分析赤潮发生前后的水环境变化,5 月调查海域海水温度有较大上升,各海域水温均超过了20 ℃,海域平均温度从4 月的15.9 ℃上升到5 月的21.9 ℃.通过本次研究发现在营养盐浓度普遍较高的调查海域,水温上升是引发赤潮的关键因素.使用专业统计软件SPSS17 发现赤潮藻类的细胞密度与水温、化学需氧量和溶解氧存在着极显著的正相关(P〈0.01),与活性磷酸盐、硝酸盐氮和无机氮存在着显著负相关(P〈0.05).另外本次调查还发现,大面积东海原甲藻赤潮暴发后,活性磷酸盐被大量消耗.综合目前有关东海原甲藻赤潮期间对活性磷酸盐的吸收动力学研究,发现今后应进一步加强这方面的调查研究.  相似文献   

2.
合成有机物结构—生物降解性关系的研究   总被引:2,自引:0,他引:2  
戴树桂  庄源益 《环境化学》1995,14(4):354-364
本文综述了合成有机物生物降解性的研究方法,以及定性结构-生物降解性关系(SBR),重点综述了芳香类化合物的结构与生物降解性的关系,研究这一关系有助于有毒化学品生物降解性的预测。  相似文献   

3.
海水中二甲基硫测定方法的研究   总被引:10,自引:0,他引:10  
胡敏  李金龙 《环境化学》1995,14(2):157-163
二甲基硫(DMS)是雨水天然酸性的贡献者和影响气候变化的重要痕量气体,本文海水中DMS测定方法,即采用冷却预浓缩技术处理海水样品,用带有火焰光度检测器气相色谱仪分析,此方法的精密度为12%,准确度为10%,对100ml海水样品最小检测量为0.054ng(DMS)。同时对色谱柱的选取,实验材料的选择,浓缩柱填充材料的选择,鼓气效率,干燥管,样品解析,样品保存等有关实验步骤进行了讨论。  相似文献   

4.
大玉竹低聚糖硫酸酯抗HSV-2病毒活性的研究   总被引:8,自引:0,他引:8  
从传统中药大玉竹中提取低聚糖Poos,用吡啶-氯磺酸法制备了它的硫酸酯衍生物S-Poos,产物经红外鉴定,证实Poos硫酸酯化后羟基连上硫酸基,硫含量为8.47%,取代度(Ds)为0.6体外实验研究了Poos、S-Poos对非洲绿猴肾细胞(Vero)的细胞毒怀和抗单纯疱疹病毒2型(HSV-2)活性。结果表明,Poos和S-Poos都无细胞毒性。Poos本身无抗病毒活性,对HSV-2引起的细胞病变和  相似文献   

5.
光合细菌在水产养殖中的应用[综述]   总被引:4,自引:0,他引:4  
光合细菌(PhotosyntheticBacteria,以下简称PSB)是地球上最早出现的一大类能以光作为能源,以CO2和有机物作为光合作用碳源,以有机物、氢气或硫化物为供氢体而营养繁殖的原核生物的总称;除蓝细菌外都能在厌氧光照条件下进行不产氧的光合作用.PSB分布广泛(见表1),类型多样,根据《伯杰细菌鉴定手册》(第九版)PSB可分为六个类群,27个属(见表2).其中的红色非硫细菌由于其分解利用有机物能力强、营养丰富,因而得到广泛的应用.表1 各种环境下PSB数量(n(PSB)/g-1)Tab…  相似文献   

6.
海水养虾池细菌数量动态及细菌生产力的研究   总被引:7,自引:0,他引:7  
对5个海水养虾池细菌数量动态及细菌生产力的研究结果表明:水层细菌数在不同试验池及同一池塘不同采样时间均呈现较大波动.细菌密度在底水层明显高于表水层,且同一虾池细菌密度在水平分布上极具不均匀性.底泥中细菌数在采样期稳定增加并与底泥中有机物含量呈现显著正相关,随着泥层加厚,细菌密度呈V型分布,最大密度出现在表层1cm之内,2cm以下泥层,细菌密度明显减小原位(in-situ)实验测定所得虾池细菌生产力ρ4(C)·t-1=86.10~343.25mg·m-2·d-1,是浮游植物初级生产力的10%~19%  相似文献   

7.
PACS的结构特征及絮凝性能研究   总被引:11,自引:0,他引:11  
高宝玉  于慧 《环境化学》1994,13(2):113-118
制备了碱化度及Al^3+/SO^2-4摩尔比不同的系列PACS,分别进行常压(干燥温度105℃)及真空干燥(真空度为-0.098MPa、干燥温度65℃)制备固体产品。用红外光谱及X-射线衍射谱研究了碱化度、Al^3+/SO^2-4摩尔比、干燥温度对PACS的结构影响,比较了干燥温度不同对PACS固体样品的溶解度及絮凝效果的影响,借助于显微电泳测定技术研究不同碱化度及不同Al^3+/SO^2-4摩尔  相似文献   

8.
香港大气中有毒挥发性有机物研究   总被引:22,自引:0,他引:22  
用吸附/热脱除-GC=/MS方法研究了香港不同功能区大气中挥发笥有机物的组成。分析结果表明,香港大气中存在60多种VOCS,其主要成分是苯系物,烷烃和卤代烃。在检出物中有17种是有毒挥发性有机物,其主要成分是苯系物和氯代烃。其中氯仿,苯,甲苯,四氯乙烯,三氯乙烯和1,2-二氯乙烷是含量最高的组分。  相似文献   

9.
研究红壤对SO4(2-)和H_2PO(4-)的吸附与竞争吸附机理.实验结果表明,红壤吸附H2PO4-的量远远大于SO4(2-),前者几乎是后者的2倍.在两种阴离子共存体系中,H2PO4-使SO4(2-)吸附量明显减少,在浓度低时甚至出现负吸附;SO4(2-)对H2PO4-吸附量的影响很小.说明土壤对H2PO4-的吸持力较强,为高强度专性吸附,不易于被其它阴离子解吸;土壤对SO4(2-)的吸持力则较弱,为低强度专性吸附或非专性物理吸附,能够被吸持力更强的阴离子完全解吸.  相似文献   

10.
湘南第四纪红壤吸附SO^2—4的机理研究   总被引:6,自引:0,他引:6  
陈铭  孙富臣 《环境化学》1995,14(2):129-133
本文研究了湘南第四纪红粘土及其发育地旱地和水田表层土壤对SO^2-4的吸附,结果表明这三种土壤吸附SO^2-4的顺序为:红粘土>旱地红壤>红壤性水稻土,而且随介质PH的升高,SO^2-4吸附量减少,吸附机理也发生改变,当介质PH<ZPC时,以置换水合基(-OH2)的方式进行,PH在3.5-6.5之间时,以置换羟基(-OH)的方式为主,PH>6.5以后,解吸占优势。  相似文献   

11.
A practical method for the quantification of total purgeable organic sulfur (POS) in highly contaminated groundwater is described. Volatile organic sulfur compounds (VOSC) are purged from the water samples by a stream of oxygen and combusted. The emerging sulfur dioxide is absorbed in H2O2 and converted to sulfate which is quantified by ion chromatography and reported as mass sulfur equivalent. The overall limit of quantification is 0.03 mg l−1. The content of POS is balanced with the total VOSC determined by GC-AED after liquid–liquid extraction. Separate determination of the non-volatile organic sulfur compounds by direct combustion of the water sample and adsorption to charcoal yielded a mass balance of the total sulfur content. Semi-quantitative GC-MS after purge & trap accumulation revealed that the VOSC mixture is composed of C1–C4 alkyl sulfides. The implementation of the developed methodology for the quantification of VOSC as potential catalyst poison in a cleaning plant for groundwater contaminated with volatile haloorganics (VOX) is presented.  相似文献   

12.
有机磷酸酯(OPEs)是一类重要的有机磷阻燃剂,近些年逐渐取代了溴代阻燃剂,广泛应用于各行各业,也因此导致在多种环境介质中有较高的暴露量和潜在风险。已有研究表明,OPEs具有一定的毒理效应,对人体及其他生物均有潜在危害。本文综述了近年来国内外OPEs的检测技术,详述了不同环境介质OPEs的前处理方法。结果表明,目前固相萃取(SPE)和固相微萃取(SPME)仍是水样前处理的主要方法;对于固体样品,加速溶剂萃取/加压液相萃取(ASE/PLE)和微波辅助萃取(MAE)应用较多;虽然大气样品仍以固体吸附剂方式为主,但已向在线一体化方向发展;而生物样品的前处理方法多与水样和固体样品方法相似;但是对于复杂环境介质中OPEs样品的前处理较为困难,方法有待改善;气相色谱-质谱联用(GC-MS)和气相色谱-氮磷检测器(GC-NPD)对弱极性和易挥发的OPEs分析效果好,而强极性和难挥发的OPEs多用液相色谱-质谱联用(LCMS);气相色谱-质谱串联(GC-MS/MS)、液相色谱-质谱串联(LC-MS/MS)和高效液相色谱-质谱串联(UPLC-MS/MS)等对多种复杂的环境介质中的OPEs均有较好的检测分析效果,但并未普及。最后,对OPEs分析测试方法的发展趋势提出了展望。  相似文献   

13.
外来入侵植物薇甘菊对华南地区的生态环境造成严重危害,为探讨薇甘菊叶片挥发性有机化合物在华南地区的空间差异,运用GC-MS分析了华南地区23个不同地理种群230个薇甘菊植株叶片挥发性有机化合物的组分,并用峰面积归一化法计算各组分相对含量;利用线性混合模型分析不同地理种群的气候环境因素对薇甘菊叶片挥发性有机化合物含量的影响;采用聚类分析和主成分分析23个不同地理种群薇甘菊叶片挥发性有机化合物组分的特征。结果表明:利用GC-MS从薇甘菊叶片中鉴定了42种挥发性有机化合物,其主要成分为β-荜澄茄油烯(24.63%)、β-石竹烯(16.81%)、大香叶烯D(10.47%)、α-古芸烯(9.95%)和α-姜烯(9.77%);线性混合模型分析结果显示经度、纬度、海拔高度和温度可显著影响薇甘菊叶片中5种主要挥发性有机化合物的含量;聚类分析和主成分分析表明薇甘菊叶片挥发性有机化合物组分表现出较强的地域特征。研究结果可为阐明薇甘菊的入侵机制及防控措施的制定提供理论与实践参考。  相似文献   

14.
There are many established extraction techniques regularly used in the isolation and analysis of PAHs and similar organic compounds from various phases. These include Soxhlet or ultrasonic extractions from solids, and liquid-liquid or solid-phase extraction from aqueous samples. However, these methods have some inherent disadvantages; most require large volumes of organic solvents, they can be time consuming and many involve multi-step processes that always present the risk of the loss of some analytes (Zhang et al., 1994). Solid-phase micro-extraction (SPME) is a relatively new technique that has been used with much success in the analysis of a variety of compounds including PAHs. Experiments are being carried out to determine the optimum range of conditions for the extraction of a range of PAHs. Parameters under investigation include temperature, equilibration time, salinity and compound concentration. Presented here are some preliminary experiments into the applicability of SPME for PAH analysis. Further work will investigate the reproducibility of the technique, limits of detection and matrix effects. When an optimised method has been developed the technique will be used in investigations into PAH profiles in sediment cores.  相似文献   

15.
近岸海水中全氟化合物的液相色谱-离子阱质谱法测定   总被引:1,自引:0,他引:1  
建立了利用高效液相色谱-电喷雾离子阱质谱(HPLC-ESI-IT-MS/MS)测定近岸海水中多种常见全氟化合物(PFCs)的分析方法.采用固相萃取法(SPE)对海水中的PFCs净化富集,用HPLC-ESI-IT-MS/MS多反应离子监测(MRM)模式对各组分(全氟己烷磺酸、全氟辛烷磺酸、全氟辛烷磺酰胺、全氟己酸、全氟庚酸、全氟辛酸、全氟壬酸、全氟癸酸、全氟十一酸、全氟十二酸)进行测定.在最佳实验条件下,采用基质匹配标准曲线法定量,以消除海水基质的影响,8种目标化合物的检出限介于0.50—1.00 ng·L-1,9种PFCs的回收率在71.0%—130.2%之间,能满足近岸海水中多种PFCs检测的要求.青岛沿岸表层海水样品测定结果显示,全部采样站点的海水样品中均检测到≥4种PFCs,说明青岛沿岸海水中已有一定程度的PFCs污染.  相似文献   

16.
The antifungal activity of molecular identified Chilean saprobiontic fungi, Trichoderma viride, Schizophyllum commune and Trametes versicolor, on the fungal plant pathogens Botrytis cinerea and Fusarium oxysporum, and the saprotrophic mould Mucor miehei was investigated using two types of inhibition bioassay: (1) bi-compartmented Petri dishes and (2) two Erlenmeyer flasks connected by their upper parts. The chemical composition of volatile organic compounds (VOCs) released by saprobiontic fungi was also investigated using headspace solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC-MS) analysis. Of the saprobiontic fungi evaluated, one isolate of S. commune showed the highest inhibitory activity against B. cinerea and M. miehei, 86.0±5.4 and 99.5±0.5% respectively. The volatile profiles of fungal isolates were shown to contain a different class of compounds. The major components in the headspace of mycelial cultures were 6-pentyl-α -pyrone (T. viride), ethanol and β -bisabolol (S. commune), and a sesquiterpene alcohol (Tr. versicolor). This is the first study reported on the release of VOCs by Chilean native fungi and their antifungal activity wrt. plant pathogenic fungi.  相似文献   

17.
茶刺蛾危害后茶树挥发性有机化合物释放变化   总被引:1,自引:0,他引:1  
为筛选引诱天敌昆虫的化学信息素,以应用其防控茶刺蛾(Iragoides fasciata Moore),研究了茶树[Camelliasinensis(L.)O.Kuntze]被茶刺蛾危害后释放出的挥发性有机物的变化.应用同时萃取蒸馏法收集被茶刺蛾危害和未危害的茶叶的挥发性有机化合物,气相色谱/质谱联用仪(GC/MS)分析结果发现,未受害枝叶挥发性有机化合物共有63种组分,主要由酯类、醇类、烃类、酮类、杂环化合物、醛类、有机酸和醚类组成,烃类物质的相对含量占19.05%,而受害枝叶释放出的挥发物中烃类物质的相对含量增加到26.79%,反式-橙花叔醇、雪松醇、邻苯二甲酸二丁酯、邻苯甲酸二异丁酯相对含量显著增加,此外,产生了32种新的组分,包括10种酯类、5种醇类、5种烯烃类、4种杂环类、3种芳香烃类、3种烷烃类、1种醛和1种酮.  相似文献   

18.
The intracellular concentrations of low-molecular weight carbohydrates and quaternary ammonium compounds present in 26 axenic isolates of unicellular cyanobacteria have been studied over a range of external salinity from freshwater up to 300% seawater (100%=35 S). In all cases, a single carbohydrate, either sucrose or glucosylglycerol, was identified as the principal organic osmoticum, showing major variation in response to the external salt concentration; quaternary ammonium compounds were present in osmotically insignificant amounts. Glucosylglycerol was accumulated as primary osmoticum by nine of the isolates from saline habitats and by five of the freshwater isolates; trace amounts of sucrose were also prsent. The remaining twelve freshwater strains accumulated sucrose as sole osmoticum. Glucosylglycerol-accumulating strains grew over the widest salinity range (up to 200 to 250% seawater), whether isolated from saline or non-saline habitats. Sucrose-accumulating strains were more stenohaline, growing only in up to 50 to 100% seawater and showing no sustained growth in hypersaline media (>100% seawater). The data suggest that (1) glycosylglycerol accumulation is not unique to marine cyanobacteria, and (2) the upper salinity limit for growth may be linked to organic solute accumulation, rather than habitat, with glucosylglycerol-accumulating isolates having a greater potential for growth in salt-stressed conditions than sucrose accumulators.  相似文献   

19.
东湖水中有毒有机物的气相色谱分析   总被引:3,自引:1,他引:3  
本文采用自制的聚硅氧烷负载氮杂18冠6(PUAC-18-C-6)和OV-101弹性石英毛细管柱对东湖水及排污口废水进行了分析,分离出78个有机化合物,并对其中的石油烃(C_9—C_(28))和有机氯农药六六六进行了定量测定。分析结果表明,东湖的污染程度受水的流向、水生生物的分布及污染源的影响。  相似文献   

20.
Endocrine disrupting compounds (EDCs), pharmaceuticals and personal care products (PPCPs) have attracted much attention due to widespread contamination in aquatic environment. In this study, we determined 13 EDCs and PPCPs in fish blood, bile and muscle by using gas chromatography-mass spectrometry (GC-MS). The limits of quantitation (LOQ) were in the ranges of 0.23–2.54, 0.22–2.36 ng·mL−1, and 0.24–2.57 ng·g−1 dry weight (dw) for fish blood, bile and muscle, respectively. Recoveries of target compounds spiked into sample matrices and passed through the entire analytical procedure ranged from 65% to 95%, from 60% to 92% and from 62% to 91% for blood, bile and muscle, respectively. The methods were applied to the analysis of fish from a lake in California. Target compounds were relatively low in bile, and only bisphenol A (BPA) and diclofenac were measurable near the LOQ. Seven of 13 compounds were detected in blood, with total concentrations up to 39 ng·mL−1. Only BPA was frequently found in muscle, with mean concentration of 7.26 ng·g−1 dw. The estimated daily intake of BPA through fish consumption for U.S. resident was significantly lower than the tolerable daily intake recommended by the European Food Safety Authority. This study showed that the exposure to the bisphenol A from fish diet is unlikely to pose a health risk.  相似文献   

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