挥发酚样品显色萃取液再次稀释测定

用4—氨基安替比林萃取光度法测定水中挥发酚时,由于一些未知水样中酚含量较高,在预蒸馏水样稀释不当时,会出现显色后的萃取液颜色过深而无法比色测定的现象,此时酚浓度常常超出方法检测上限,若再重新取样耗时太多,采取将萃取液用氯仿再次稀释后比色测定的方法较好。试验证实,此法在超出检测上限的一定浓度范围内,显色反应仍是完全的,对显色后的萃取液,再次稀释测定是准确可靠的。     

苯胺对水中挥发酚测定干扰规律的研究

HJ 503-2009《水质挥发酚的测定4-氨基安替比林分光光度法》中,提到苯胺对本方法有干扰,但未进行具体情况的研究并给出具体的消除方法。实际监测工作中苯胺对实验的干扰情况复杂,需要依据具体的情况进行解决：当水样中苯胺浓度在1 mg/L以下时,苯胺对该方法测定水中挥发酚没有干扰;当苯胺浓度在1～10 mg/L时,可以用盐酸调节水样的pH值以消除苯胺干扰;当苯胺的浓度≥10 mg/L时,苯胺对该方法测定挥发酚产生显著的干扰,不适合采用光度法进行测定,建议萃取后采用气相色谱-质谱或液相色谱法进行测定。     

紫外光度法测定水中挥发酚的研究

在国家标准方法中,测定挥发酚用4-氨基安替比林直接光度法和萃取光度法。但该方法测定范围小,上下限分别是2.5mg/L和0.12mg/L,且4-氨基安替比林、铁氰化钾等试剂不稳定,影响测定结果的准确度,方法繁琐。文章提出用紫外光度法测定水中的挥发酚。此方法不仅使测定范围增大到0.409～120mg/L,减少水样稀释比过大引起的误差及干扰,而且简便、快速、准确。通过实验证明,本方法与标准方法有很好的可比性及重现性。     

影响挥发酚测定因素的探讨

本文对普遍采用的4-氨基安替比林萃取分光光度法测定饮用水中挥发酚的多种影响因素进行了探讨，获得的结果对饮用水中挥发酚的准确测定有较好的实用性。     

地表水中挥发酚测定影响因素分析

论述了地表水中挥发酚测定结果的主要影响因素。利用实验测定了不同净化方式对4-氨基安替比林的净化效果,通过比选确定日常以三氯甲烷萃取和乙醇洗涤两种方式作为4-氨基安替比林净化方法。同时,分析了三氯甲烷、铁氰化钾对测定结果产生的影响,为地表水中挥发酚的准确测定提供一定的参考。     

土壤中挥发酚的测定及质量控制

采用分光光度法测定土壤中的挥发酚，详细介绍了样品预处理方法，分析过程中的质量控制及土壤中有机物、矿物油对测定干扰的消除方法。分析结果表明：平行双样的相对偏差都低于其最大允许值，加标回收率在78.6％～81．7％范围内，测定结果具有较好的精密度和准确度。     

光度法测定挥发酚的实验研究

文章对挥发酚测定过程中可能影响检测结果的因素进行研究。探讨实验用无酚水的制备与保存,无酚水的替代用水,蒸馏预处理的技术要求,标准曲线制作的方法改进,加药比色中常见的问题。得出:在挥发酚的测定实验中,要使用无酚水或等质量的实验用水进行试剂配制和样品测定,要进行蒸馏预处理等,提高了测定数据的准确性。     

4—AAP萃取光度法以蒸馏水代替无酚则定地面水中挥发酚

本文经过实验分析提出以蒸馏水代替无隶测定地面水虽挥发酚，结果表明，本方法检出限为０．００１７ｍｇ／ｌ，具有较高的精密度和准确度。本法省略了制备无酚 程序，从而使实验分析得到简化。     

东北某企业地下水中挥发酚运移模拟

以东北某化工企业为主要研究对象，对该区域内的地下水进行了调查。作为典型案例，通过对该 场地区域内地下水的调查研究，分析其地下水中挥发酚类物质对环境的影响，在此基础上建立地下水数值模 型，预测挥发酚类物质的迁移程度。结果表明：该场地区域内地下水中污染物主要为挥发酚类物质；通过对厂 区内10a的溶质运移模拟，对比1,5,10a后的挥发酚分布情况，场地内的挥发酚并不会影响到下游流域；10a后，挥发酚的浓度集中在0.002～0.1mg/L，较现阶段发生了明显的降解效应。     

4－氨基安替比林分光光度法测定水中挥发酚的影响因素

本文介绍了测定挥发酚过程中加蒸馏水顺序、预蒸馏时的pH值、预蒸馏前试剂加入顺序、显色时试剂加入顺序、显色剂纯度、显色时间等因素对挥发酚测定的影响。实验结果表明预蒸馏时的pH值、试剂加入顺序、显色剂纯度、显色时间对测定结果都有一定影响。控制好上述条件才能获得较准确的结果。     

SPE-HPLC/MS联用法测定地表水中的PFOA及PFOS含量

本文建立了固相萃取与高效液相色谱／质谱（HPLC／MS）联用的方法来测定地表水中全氟辛酸（PFOA）及全氟辛烷基磺酸（PFOS）的含量。此方法中PFOA在水样中的线性范围为40ng／L到500ng/L，线性相关系数0．9986，PFOS在水样中的线性范围为5n异／L到500ng/L，线性相关系数0．9905。此方法中全氟辛酸及全氟辛烷基磺酸的平均回收率分另13为83.91％和86.63％。水样中全氟辛酸和全氟辛炕基磺酸的检出限均为0.5ng／L。方法准确、可靠，分析结果令人满意。采用此方法测定了上海部分地区地表水中全氟辛酸及全氟辛烷基磺酸的含量。实验结果表明，上海地区长江入海口处徐六泾段全氟辛酸的平均浓度是46．88ng／L，全氟辛烷基磺酸未检出；黄浦江段全氟辛酸及全氟辛烷基磺酸的平均浓度分别是1594．83ng／L（前处理后需稀释10倍以确保在方法线性范围内）和20．46ng/L。可见长江及黄浦江流域的全氟辛酸及全氟辛烷基磺酸的控制与治理亟待提上议程。     

Phosphorus in runoff assessed by anion exchange resin extraction and an algal assay

Eutrophication of surface waters can be accelerated by agricultural inputs of phosphorus (P), provided that P is in a form that can be utilized by aquatic algae. We studied anion exchange resin (AER) extraction and a dual culture algal assay (DCAA) for the determination of potentially algal-available P in water samples without sediment preconcentration. Our material consisted of agricultural and forest runoff and wastewaters. The results obtained by the two methods were essentially equal when the samples contained only small amounts of particulate phosphorus (PP) in relation to dissolved molybdate-reactive phosphorus (DRP). However, in turbid agricultural runoff, P extracted with AER averaged 72% (n = 17) of the P yield of the 3-wk DCAA (R2 = 0.94). When the runoff samples were diluted for the AER extraction in the same manner as for the DCAA, the AER-P yield increased to 85% (n = 5) of DCAA-P. The minimum detectable value was greater for the AER test (41 microg L(-1) AER-extractable P) than for the DCAA (7 microg L(-1) DCAA-P). At concentrations greater than about 50 microg L(-1) AER-P or DCAA-P, the accuracy of the methods was satisfactory, with the coefficient of variation in replicated analyses being less than 10% for the AER test and less than 20% for the DCAA. Other anions competing for the exchange sites of the AER decreased P recovery by 15 to 20% when their equivalent concentration exceeded about 4 mmol, L(-1), and this effect was relatively constant over a large concentration range. We consider that AER extraction is a suitable low-cost method to estimate the algal availability of P in runoff samples.     

Investigating the phenol removal from aqueous media by photocatalytic magnetized graphene oxide nanocomposite

As a large and diverse group of secondary metabolites, phenolic compounds are one of the most common chemical pollutants present in water resources. these compounds can have toxic effects on ecosystems and humans. Therefore, their removal from water sources appears to be of great importance. In this study, a magnetic graphene oxide (MGO) photocatalyst was synthesized and used to remove phenol from water. The fabricated GO magnetic nanocomposites were determined by SEM and FTIR techniques. Afterward, these nanoparticles were used to remove phenol from aquatic media considering different operational parameters, including pH of the solution, initial concentration of phenol, contact time, and adsorbent dosage. The results showed that the magnetized GO nanoparticles could remove 90.83% of phenol molecules under the optimal conditions of solution pH = 3.0, initial phenol concentration of 20 mg/L, adsorbent concentration of 300 mg/L, and contact time of 120 min. additionally have compared the results of UV, Fe₃O₄/GO, and Fe₃O₄/GO/UV on the removal of phenol under optimum conditions. Accordingly, the phenol removal efficiencies for UV alone, Fe₃O₄/GO, and Fe₃O₄/GO/UV were obtained at 4.5, 65.73, and 90.83%, respectively. Based on the findings, the prepared magnetic GO nanoparticles have extended capabilities such as easy and rapid separation from sample and high potential in removing phenolic compounds, so, it can be introduced as an appropriate adsorbent for removal of this pollutant from water and wastewater.     

酸水汽提净化水中酚的治理技术研究

采用吸附法对酸水汽提净化水中的酚进行了处理。这种方法不仅可以满足对实验浓度酚的处理,同时可以回收酚。通过吸收过程及不同流速对比实验得出:树脂的吸附效果显著,吸附能力较强,吸附时间较长;净化水的流速与吸附效果具有一定的线性关系;不同流速吸附效果不同,对应树脂需要再生的时间也不同。应用结果表明:吸附法中较可行的方法为树脂吸附法。     

苯酚降解菌Y_1的分离与鉴定

旨在从微生物降解的角度出发,解决苯酚大量应用带来的含酚废水对环境污染问题.采用富集培养、驯化筛选和平板划线等方法,从某化工厂废水中分离得到4株苯酚降解菌.利用4-氨基吡啉分光光度法测定其苯酚降解能力,筛选出降解率较高的菌株Y_1.经形态学观察、生理生化鉴定和16S rDNA序列分析,将该菌初步鉴定为苏云金芽孢杆菌(Ba...     

分光光度法测定硝酸盐氮中的干扰因素

对酚二磺酸分光光度法测定水样中硝酸盐氮的标准方法进行研究,在不同浓度的氯化物、氨氮和亚硝酸盐氮中加入不同浓度的硝酸盐氮标准溶液进行干扰试验。结果表明:在最佳的试验条件控制下,氯离子对低浓度硝酸盐氮测定产生的负干扰明显大于对高浓度硝酸盐氮产生的负干扰;随着加入的氨氮和氯化物浓度的增加,硝酸盐氮含量的测定结果低于实际值,且逐渐减小;在试验浓度范围内亚硝酸盐氮浓度对硝酸盐氮的测定几乎无影响。     

光催化氧化苯酚中间产物的分析与降解途径探讨

采用光催化氧化法降解苯酚溶液，利用液相色谱对苯酚及其中间产物进行了定性、定量分析。考察了投加H2O2对中间产物浓度变化的影响。根据中间产物的产生情况及浓度变化，推测了苯酚光催化降解的反应途径。     

Escherichia coli load reduction from runoff by vegetative filter strips: a laboratory-scale study

Vegetative filter strips (VFS) are commonly used best management practices for removing contaminants from runoff. Additional research is warranted to determine their efficiency and the most appropriate metrics for predicting fecal bacteria reductions. The objective of this research was to determine VFS effectiveness in removing from runoff relative to inflow rate, infiltration capacity, and flow concentration. This research also investigated the presence of in runoff from clean water runon after diluted manure runon events. A laboratory-scale VFS soil box (200 cm long, 100 cm wide, 7.5% slope) was packed with a sandy loam soil. Ten constant-flow VFS experiments were conducted with and without vegetation (8-10 cm ryegrass [ L.]) at low (20-40 cm s), medium (40-60 cm s), and high (85-120 cm s) flow rates and for a full (100 cm) or concentrated (40 cm) VFS flow width to simulate a channelizing flow condition. Two runon events were investigated for each experimental condition: (i) diluted liquid swine manure runon and (ii) clean water runon 48 h afterward. was used as an indicator of fecal contamination and was quantified by the most probable number (MPN) technique. No concentration reductions were observed based on peak outflow concentrations, and only small concentration reductions were observed based on outflow event mean concentrations. The mass reductions ranged from 22 to 71% and were strongly correlated to infiltration or runoff reduction ( = 0.88), which was dependent on the degree of flow concentration. Little to no effect of sedimentation on transport was observed, hypothesized to be due to minimum attachment to sediment particles because the bacteria originated from manure sources. Therefore, the design of VFS for bacteria removal should be based on the infiltration capacity in the VFS and should prevent concentrated flow, which limits total infiltration. The event mean concentrations in clean water runon experiments were between 10 and 100 MPN per 100 mL; therefore, under these conditions, VFS served as a source of residual from previous runon events.     

乳化液膜法处理石油石化废水的研究

炼厂酸性汽提净化水中酚含量高，限制了汽提净化水回用效率，需进行脱酚处理。本研究采用煤油、span-80、液体石蜡、磷酸三丁酯和NaOH构建乳化液膜，探究其对酸性水汽提净化水的脱酚效率。运用以响应曲面法（RSM）为依据的Box-Behnken设计，以span-80投加量、液体石蜡投加量、油相/内相比和制乳转速为影响因素，建立了汽提净化水中苯酚去除率的二次回归预测模型，并优化了处理条件。结果表明，液体石蜡投加量对苯酚去除率的影响最为显著，其次是span-80投加量。通过RSM分析得到汽提净化水脱酚的最佳实验条件为：span-80投加量2wt%，液体石蜡投加量15%v/v，油内比为1:1，制乳转速取6000r/min，此时苯酚去除率为98.65%。反应后的液膜易于破乳，破乳率达98.33%，且回收油相可循环利用，从而大大节约成本实现资源化。     

XDA-1型大孔吸附树脂对水中氯仿的吸附性能

研究了XDA-1型大孔吸附树脂对用自来水配制的低浓度溶液中氯仿的动态吸附能力,以及浓度、流速、温度和pH等因素对吸附过程的影响.结果显示,采用XDA-1大孔树脂吸附水中的氯仿,其吸附效率可达99%以上,泄漏点前的吸附量为160mg/ml.采用热空气热解吸方式回收氯仿,回收率达85%,为含氯仿工业废水的处理提出一种新的处理工艺.