紫外光诱导荧光分析仪结合多元线性回归算法在城市河流常规污染指标监测中的应用

为建立一种针对城市河流水体常规污染指标的快速原位监测方法,首次运用紫外光诱导荧光分析仪对扬州市60条城市河流进行水体三维荧光光谱(EEM)测量,形成了具有多样性的水质样本集合.利用峰值拾取法、相关性分析和主成分分析3种方式从三维荧光光谱中提取溶解性有机物(DOM)污染信息,结合多元线性回归算法(MLR),建立与化学需氧...     

水纹预警溯源技术在地表水水质监测的应用

针对地表水对污染预警和溯源技术的迫切需求,在南方某水体开展水质指纹预警溯源技术的应用研究。结果表明,该水体的水纹在激发波长230 mm、发射波长340 nm和激发波长280 nm、发射波长320 nm处有2个代表性荧光峰。2个峰的荧光强度与氨氮呈线性正相关。枯水期的荧光强度较高。清华大学已将水纹溯源技术仪器化。在长期在线监测过程中,污染预警溯源仪检测到水情异常并快速确定了污染类型,为环境监管提供了有力的技术支撑。     

应用水质标识指数法评价太湖湖滨带水质

以2009年12月和2010年4、8月的全太湖湖滨带水质监测数据为基础,以TN、TP、NH₃-N、COD_Mn、DO为评价指标,采用水质标识指数评价法对太湖湖滨带水质进行评价。水质指标基本信息显示,NH₃-N冬季、春季空间变异较大,TP夏季空间变异较大;单因子标识指数评价结果显示,太湖湖滨带水体水质因子污染风险时空差异显著,TN冬季、春季全区域污染风险均较大,NH₃-N冬季和夏季在竺山湾、西部沿岸区域污染风险较大,TP三季在竺山湾、西部沿岸区域污染风险较大;综合标识指数评价结果显示,东太湖、东部沿岸、贡湖区域水质较好,为Ⅲ类水,竺山湾和西部沿岸水体水质最差,为Ⅴ类水,且竺山湾和西部沿岸水体三季均处于重度污染状态。该研究可为太湖湖滨带水环境的生态恢复和标识指数应用的推广提供一定的科学依据。     

畜禽养殖废水的三维荧光特征

对某畜禽养殖废水连续采样,利用荧光光谱法研究畜禽养殖废水的三维荧光特性.结果表明:该废水的三维荧光光谱有两个荧光峰,分别为270 nm/297 nm和315 nm/410 nm,两峰的强度之比为3.45～4.94;该畜禽养殖废水由蛋白质、腐酸、尿液及阴离子表面活性剂组成;各峰的峰位置及峰强度比值都可作为判断废水是否为该...     

太湖流域河流入河污染负荷通量与入湖水质响应关系分析——以殷村港为例

以2020年1—12月太湖主要入湖河流殷村港水质自动监测站的监测数据及2020年太湖水位资料为依据,构建了一维水量水质耦合数学模型,建立了入河污染负荷通量与入湖控制断面水质响应关系,以入太湖控制断面殷村港站达Ⅲ类水质水为目标,模拟计算了殷村港站主要污染物入湖水质变化过程。结果表明,殷村港站高锰酸盐指数、氨氮、总磷等水质指标浓度最大值均明显的降低,其中氨氮浓度降低幅度相对较大,主要集中于3—6月;高锰酸盐指数和总磷日均入河污染负荷通量变化相对较小,氨氮日均入河污染负荷通量降低幅度相对较大;殷村港站高锰酸盐指数、氨氮、总磷等水质指标年入河污染负荷削减量分别为24.17,41.43,3.87 t。提出,基于核算出的削减量需进一步结合污染负荷通量过程和污染源溯源分析,确定不同水质指标下入河污染负荷控制方向,为科学合理规划殷村港主要污染物的入河污染负荷总量控制提供科学依据。     

基于紫外可见吸收光谱微型污染溯源站的村镇水环境监测技术研究

为实现村镇分散度高、随机性强的水环境污染的高效管控,采用以紫外可见吸收光谱技术为核心的微型污染溯源站,于2022年4月1—14日对某县域村镇的河流水环境开展了在线监测溯源研究。结果表明,监测期间共发生2组污染事件,微型污染溯源站快速响应,氨氮、电导率等常规指标之间具有较强的相关性,各指标中,氨氮受冲击波动最为显著,最适合用于污染事件报警。通过紫外可见吸收光谱可识别污染事件之间的差异,第1组污染事件光谱特征为205 nm波长吸光度下降,疑似为硝态氮浓度下降;第2组污染事件光谱特征为230 nm波长出现显著吸收峰,疑似为水中烯-酮共轭双键类有机污染物含量大幅增加。多元线性回归拟合结果表明,2组污染事件可能分别由污水处理厂工艺波动导致的超标排放和上游化工类企业的偷排造成。研究结果为微型污染溯源站实现对不同污染情景的报警和溯源提供了依据。     

太湖水草监管体系构建初步研究

随着太湖地区的经济发展及湖泊资源的利用,太湖水草的爆发性生长已经成为提高太湖水质、维持生态系统稳定的严重阻碍。水草枯亡后可能会导致水质异常,进而给苏州市饮用水安全带来威胁。依据4年来对太湖主要湖区水草的群落结构、分布范围、季节更替的研究,初步构建了太湖水草监管体系,为政府部门实施系统性监管提供支撑,并在全国湖泊水草监管方面发挥积极的示范作用。     

太湖水环境时空演变及污染特征分析

分析研究太湖30年来的水质演变及近年来的水文径流数据,得出了太湖中存在的主要湖流。同时结合太湖特定的地理条件及水文特点,将大太湖分成湖岸区、过渡区和湖心区,对比分析了各个湖区间水质的相互影响及变化规律,得出了太湖的主要污染特征。     

特殊风场条件对太湖蓝藻水华迁移的影响研究

在高温、微风气象条件下,适宜蓝藻水华形成。在特殊非均一风场的驱动下,太湖蓝藻水华迁移过程与被均匀风场驱动有所不同。选取太湖典型风向进行分析,并采用三维水动力水质模型对表面非均一风场条件下的风生流流场及水质进行模拟,结果表明,在特殊非均一风场的驱动下,当太湖蓝藻浓度较高时,容易在西部湖区特别在竺山湖、梅梁湾湾内、岸边及湾口聚集,形成水华暴发,这有助于研究太湖污染物及蓝藻水华的输移及空间分布和机理。     

三维荧光光谱法测定市政污水中有机污染物

采用三维荧光光谱法和传统水质分析法分别测定广州某城市污水厂污水处理过程中不同节点的污水水质,并分析荧光特性与传统分析方法获得的数据之间的关系。结果表明,随着污水水质情况的改善,污水样本的特征峰荧光强度呈现出明显的下降趋势,且污水荧光强度与COD、BOD5值存在较好的相关性,可通过直接分析污水的荧光特性来判断污水的有机污染情况;相较于过滤处理的污水样本,未过滤水样的特征峰荧光强度与污水COD、BOD5值之间具有更强的线性关系。     

Assessment of organic pollution of an industrial river by synchronous fluorescence and UV–vis spectroscopy: the Fensch River (NE France)

To rapidly monitor the surface water quality in terms of organic pollution of an industrial river undergoing restoration, optical methods (UV–visible spectrometry and fluorescence) were applied in parallel to classical physical–chemical analyses. UV–visible spectra were analyzed using the maximum of the second derivative at 225 nm (related to nitrates), specific absorbance at 254 nm (SUVA₂₅₄), and the spectral slope between 275 and 295 nm (S _275–295) (related to the aromaticity and molecular weight of dissolved organic carbon). The synchronous fluorescence spectra (wavelength difference = 50 nm) exhibited a high variability in the composition of dissolved organic material between the upstream and downstream sections and also versus time. The principal components analysis of the entire set of synchronous fluorescence spectra helped to define three river sections with different pollution characteristics. Spectral decomposition was applied to the two most upstream sections: five fluorophores, classical in rivers impacted by domestic sewage and related to protein-like (λ _ex = 280 nm) and humic-like fluorescence (M-type with λ _ex ≈ 305–310 nm and C-type with λ _ex ≥ 335 nm), were identified. The irregular shape of the synchronous fluorescence spectra in the most downstream section is likely due to organic pollutants of industrial origin; however, their variability and the complexity of the spectra did not allow the further elucidation of their nature.     

Study of the effect of pH, salinity and DOC on fluorescence of synthetic mixtures of freshwater and marine salts

In order to provide support for the discussion of the fate of organic matter in estuaries, a laboratory simulation was performed by changing freshwater ionic strength, pH and organic matter content. The change in spectroscopic characteristics caused by variations in salinity, pH and organic matter concentration in the filtered samples was observed by UV-Vis and fluorescence spectroscopy. The increase in emission fluorescence intensity of dissolved organic matter (DOM) due to increasing salinity (in the range 0 to 5 g l-1) is affected by the pH of the samples. The emission fluorescence intensity at the three maxima observed in the fluorescence spectra, is linearly correlated with dissolved organic carbon (DOC) concentration at several salinity values in the same sample. The increase in organic matter concentration caused a shift in the emission peak wavelength at 410 nm for several salinity values. We concluded that it is necessary to take into account the influence of salinity and pH on emission fluorescence of dissolved organic matter if it is to be used as a tracer in estuarine or near shore areas.     

加速溶剂萃取-高效液相色谱法测定环境空气中的苯并(a)芘

采用加速溶剂萃取一高效液相色谱法荧光检测器测定环境空气中的苯并（a）芘,以乙腈／水为流动相,检测器激发波长为290nm,发射波长为430nm。方法线性良好,检出限为0．08μg／L,当采样体积为1080m。时,最低检测质量浓度为3×10^-7μg／m^3（标准状态下）,实际样品加标回收率为87．2％～109％。与超声波萃取法相比,两种方法回收率相近,而加速溶剂萃取法乙腈用量更少。     

高效液相色谱法测定化妆品中二苯酮-2、二苯酮-3与甲氧基肉桂酸乙基己酯

采用高效液相色谱二极管阵列检测器同时测定化妆品中二苯酮-2、二苯酮-3与甲氧基肉桂酸乙基己酯,以乙腈和水为流动相梯度洗脱,335 nm为检测波长,以保留时间和紫外光谱特征定性,外标法定量。3种化合物在1.00 mg/L~150 mg/L范围内线性良好,最低检出质量分数均为0.015%,基质加标平均回收率为96.2%~117%,RSD为0.2%~1.0%。     

液相色谱法测定土壤中苯并(a)芘

用快速溶剂萃取法ASE300对土壤样品进行前处理,以配有荧光检测器的高效液相色谱仪分析土壤样品中苯并(a)芘的含量,该方法以乙腈、水梯度比例混合作为流动相,流速为1.0 ml/min;激发波长和发射波长分别为255 nm和420 nm;保留时间为27.58 min。样品的称样量为25 g时,测定检出限为8.28×10-5mg/kg,相对标准偏差(RSD)为1.0%~12%,回收率为60%~87%,以上指标均能满足环境中土壤样品的检测要求。     

选择双波长分光光度法测定水中余氯

余氯在pH6.5条件下与PADA发生显色反应,本文根据稳定悬浮颗粒对光的吸收行为研究选择波长测定水体中余氯,实验证明在450～515nm波长范围内任意选择两波长比色按照推导公式和模型计算余氯浓度,测定方便结果准确,且计算模型稳定,几乎不受操作环境影响。适合于废水和天然水的监测。     

同步荧光光谱法测定环境水样中的多环芳烃

为了建立快速测定水体中多环芳烃的方法,用恒波长同步荧光法对14种多环芳烃混合标样进行了分析。在优化的实验条件下,对环境水样进行分析,可以鉴别出11种多环芳烃。14种PAHs在0～1000ng/ml范围内呈良好的线性关系,相关系数r均不小于0.9988,相对标准偏差(RSD)在1.06%～1.67%之间(n=6)。14种PAHs的检出限在0.072～3.9ng/ml之间。该方法应用于污水、样河水样、池塘水样中的多环芳烃检测取得了良好的效果,回收率分别为82.2%～111.0%、86.0%～107.0%、88.0%～106.2%(n=5)。     

Analysis of river water samples utilising a prototype industrial sensing system for phosphorus based on micro-system technology

The application of a phosphorus monitoring device based on microsystems technology (MST) to the analysis of river water is presented. An alternative to the standard molybdenum blue method known as the yellow vanadomolybdophosphoric acid method has been very effectively implemented. The method is simple, a reagent and sample are mixed in a 1:1 ratio forming a yellow complex that absorbs strongly below 400 nm in the UV spectrum. The kinetics of the reaction are rapid and sample turnaround is typically 3 min at room temperature. Therefore a very uncomplicated microfluidic design can be adopted. The working wavelength was chosen as 380 nm to coincide with the peak output of a UV-LED narrow bandwidth light source recently developed by Nichia. The limit of detection for the yellow method in the microfluidic system is 0.2 ppm with a dynamic linear range from 0-50 ppm. The method was applied to a measurement of phosphorus in a local river at specific sampling points along its course.     

Determination of three alkylphenol isomers in various water samples using a new HPLC method based on a duet stationary phase

The level of three alkylphenols (APs) 4-nonylphenol, 4-octylphenol and 4-tert-octylphenol was monitored in various water samples using a new developed and validated HPLC method. The HPLC method employed a column with a mixed-mode stationary phase (C18/SCX) using a mobile phase of water to methanol?=?15:85 (v/v) delivered at a flow rate of 1 mL/min at room temperature. Both diode array, DAD and fluorescence, FLD detectors were employed. The method is linear when APs concentration ranged from 0.025 to 0.5 μg/mL with a DAD detection at 279 nm and between 0.0008 and 0.1 μg/mL when the detection was made by FLD (excitation at 220 nm, emission at 315 nm). The limit of detection and limit of quantitation for alkylphenols were found to be 5 and 15 ng/mL, respectively (detection by DAD). The method was employed with good results for the determination of APs in the presence of polycyclic aromatic hydrocarbons in various water samples.