改进的还原偶氮光度法同时快速测定水中硝基苯和苯胺

对测定方法进行了改进,建立了用还原-偶氮分光光度法同时快速测定水中硝基苯和苯胺的分析方法。根据实验原理,对样品前处理装置进行了改进,实验步骤得到了简化,避免了样品溶液过滤转移过程造成样品损失,使样品前处理实验效率提高了90%以上;改进后的测定方法不仅可快速测定样品中硝基苯,还可同时测定样品中苯胺;达到了用一种分析方法同时测定样品中两种污染物的目的。方法精密度测定结果,相对标准偏差(n=6,RSD)为1.9%~3.2%;对硝基苯、苯胺混合标准样品以及实际废水样品进行了测定,并与原测定方法及苯胺国标测定方法进行了比对实验;测定结果具有一致性。加标实验回收率为96%~101%,表明方法准确可靠,可用于水和废水中硝基苯或硝基苯和苯胺的同时测定。     

水中苯胺类化合物分析的难点

结合实验研究了水中苯胺类化合物的测定难点和影响因素,包括样品保存和水样中悬浮物的影响。苯胺类化合物易被氧化,样品不易保存且受悬浮物的影响。研究结果表明：样品中未加入抗氧化剂进行保存时,部分苯胺类化合物迅速降解;当样品中加入80 mg/L硫代硫酸钠进行保存时,部分苯胺类化合物的保存时间可以延迟2~3 d后降解。样品中悬浮物对联苯胺萃取影响较大,回收率偏低,可以通过调节样品pH至酸性后过滤,再将滤液调至中性后进行萃取,回收率明显提高。笔者同时讨论了消除与补偿基质干扰的方法,包括色谱分离条件和检测器条件的选择、优化,内标法、空白基质匹配标准校正法和工作曲线法等定量方法的选择。     

紫外差示分光光光度法直接测定废水中苯胺

苯胺在不同酸度溶液中具有不同的结构和紫外吸收光谱.以苯胺的酸溶液为参比液,以等浓度的苯胺水溶液为测定液,在280nm处测定苯胺含量.结果表明,当苯胺浓度为1～100mg/L时,吸光度与浓度之间存在良好的线性关系,据此建立了紫外差示分光光度法.该法不需分离可直接测定工业废水中苯胺含量,简便快速,回收率高于96.7％.     

TU-1901紫外可见分光光度计用于污水中酚类和苯胺类的快速测定

介绍了用ＴＵ１９０１紫外可见分光光度计直接、快速测定环境污水中酚类和苯胺类的实验方法。污水样品用１∶１盐酸调ｐＨ为３０±０１,直接测绘吸收光谱,微机４阶微分后即可同时获得酚类和苯胺类的含量,方法简捷、快速、节省试剂且无污染,所用仪器为国产的先进仪器,在环境监测领域有广阔的应用前景     

液-液萃取-气相色谱法同时测定水中吡啶、松节油和苯胺

研究建立了气相色谱法同时测定水中吡啶、松节油和苯胺的方法.采用二氯甲烷萃取,萃取后直接进行色谱分离分析,3种物质能够有效分离.吡啶、松节油和苯胺的水中最低检测浓度分别为0.009、0.009、0.004mg/L,样品添加平均回收率为89％～114％,平行6次精密度实验,相对标准偏差小于6.5.实验结果表明,气相色谱法简单、快速、准确,适用于水中吡啶、松节油和苯胺的测定.     

水环境污染事件中苯胺的测定与方法选择

针对苯胺泄露污染事故,应急监测中采用分光光度法、液相色谱法（紫外检测、荧光检测）、便携式气相色谱一质谱法、速测管法等5种方法测定苯胺,对这5种方法的分析时间、精密度、准确度和检出限等效能进行比较,并比对其测定结果.试验表明,5种方法各具优势和不足,实际应用中选择方法时需考虑方法的适用性.     

乙腈盐析萃取HPLC-PDA同时测定水中11种苯胺类化合物

通过对色谱分析和样品萃取条件的选择和优化,建立了同时分析水中11种苯胺类化合物的HPLC方法。样品经乙腈盐析萃取后直接进样分析,采用 ODS色谱柱,以乙腈-水为流动相进行梯度洗脱,用PDA检测。结果表明,11种苯胺类化合物在0.20~100mg/L范围内其浓度和检测信号呈良好的线性关系,方法检出限为0.002~0.007mg/L,地表水和废水样品加标回收率为81.6%~97.4%,相对标准偏差为1.5%~5.5%。     

水中紫外吸光度与COD的相关性

通过对地表水、生活污水和工业废水样品的紫外吸光度与化学需氧量（或高锰酸盐指数）测定值进行线性回归分析,得出不同类型水体的紫外吸光度与化学需氧量（或高锰酸盐指数）之间具有良好的相关性,在一定条件下,可利用测定的紫外吸光度推算出化学需氧量（或高锰酸盐指数）结果。     

污水处理厂废水中苯胺类化合物的测定及生态风险分析

本研究建立了固相萃取结合高效液相色谱-串联质谱法测定水样中苯胺类化合物的方法,水样前处理使用PCX固相萃取小柱吸附苯胺类化合物,以甲醇溶剂洗脱,采用ZORBAX Eclipse Plus C18色谱柱,电喷雾质谱正离子模式,以乙腈-0. 2%甲酸水为流动相,梯度洗脱,同时测定水样中12种苯胺类化合物。结果显示,进水中12种苯胺类化合物加标回收率62.3%～119%,日内精密度为2.55%～11.8%,日间精密度为4.17%～13.6%;出水中12种苯胺类化合物加标回收率为70.5%～115%,日内精密度为2.49%～10.5%,日间精密度为3.01%～15.5%;12种物质的检出限为0.25～1.97μg/L。该方法操作简单、结果准确,能够满足水样中12种苯胺类化合物的定性定量测定,可同时处理大批样品。用该方法对江苏省淮安市18家污水处理厂的进、出水样进行了测定,12种苯胺类化合物在18个采样点均能检出,其中N,N-二乙基间甲苯胺检出水平最高,平均值为15.29ng/L,2,6-二甲基苯胺同样检出水平最低,平均值为5.22 ng/L。采用风险商值法评估对12种苯胺类化合物进行了生态风险评估,结果表明二苯胺、苯胺和间甲苯胺为中等潜在生态风险,其他均为低生态风险。     

顶空气相色谱法测定水中苯胺

采用顶空气相色谱法测定水中的苯胺,对盐类及其用量、顶空温度等条件进行了优化。当加入5 g NaOH,80℃进行顶空时,苯胺在0.02~0.50 mg/L范围内线性良好,方法检出限0.002 mg/L,样品加标平行测定的RSD<5.0%,回收率>95%。方法操作简单,检出限低,适用于水体中苯胺的测定。     

紫外分光光度法在水中阴离子表面活性剂标准样品研制中的应用

研究了阴离子表面活性剂水溶液的紫外吸收特性,并将研究结果用于阴离子表面活性剂水质标样的稳定性,均匀性和定值工作,简化了操作手续,获得了准确的分析结果。     

Promoting corporate sustainability through sustainable resource management: A hybrid decision-making approach incorporating social media data

Previous studies revealed triple bottom line cannot entirely cover the concept of corporate sustainability. This study thus uses sustainable resource management (SRM) to improve corporate sustainability (CS) performance considering the socio-environmental, socio-economical, and eco-efficiency aspects. In this study, the vague set (VS) theory and the technique for order preference by similarity to ideal solution (TOPSIS) method are integrated as a hybrid decision-making tool by which social media data can be transformed into entropy weights. The results indicate eco-efficiency and society should be prioritized to improve the corporate sustainability performance. Specifically, the aspects should be promoted through encouraging environmental innovation, redesigning consumers' offer, raising support of the institutions and policy measures, and organizing synergetic involvement. The contributions of this study are three-fold: (i) establishing a comprehensive framework for guiding firms make effective improvements; (ii) developing a hybrid VS-TOPSIS method to process the assessment data and social media information and address the interrelationships; (3) identifying the decisive SRM criteria to precisely guide the Chinese automobile industry towards CS under severe resource constraints.     

波长色散-X射线荧光光谱法测定PM2.5中23种元素

研究以单元素标准膜为基础,结合NIST SRM 2783颗粒物滤膜标准样品,建立了波长色散-X射线荧光光谱法测定PM_2.5中23种无机元素的测定方法,优化了测试条件,测量一个样品耗时约15 min,计算了各元素的方法检出限。对NIST SRM 2783滤膜标准品在一周内重复测定10次来计算方法的准确度与精密度,测定结果显示大多数元素的测量值在给出的参考值范围内,且测量标准偏差一般在10%以内。对比了石英与聚四氟乙烯材质（Teflon）滤膜的空白值,石英滤膜中Si、Fe、Na、Mg、Al、K、Ca等元素的背景值较高,Teflon滤膜的背景值较低,推荐选用Teflon滤膜作为PM_2.5组分分析采样滤膜。分别用波长色散-X射线荧光光谱法及酸消解-ICP-MS法测定了样品膜中的元素组分,得到的测定结果基本一致。     

美国NIST元素汞发生器的基准溯源传递方法

综述了美国NIST元素汞发生器的基准溯源传递方法,通过在输出的汞标准气体中混合加入已知高纯度的201Hg0气体（201Hg2＋标准溶液还原雾化）,并采用同位素稀释电感耦合等离子体/质谱法（IDICP/MS）测量加标后201Hg/202Hg同位素丰度比例,计算出待溯源元素汞发生器输出的Hg0 质量浓度.该过程实现了从元素汞一级标准物质SRM 3133到201Hg2＋标准溶液,再到元素汞发生器输出标准气体的溯源传递,完成了从NIST元素汞基准到仪器供应商生产基准的一级溯源传递,为建立符合我国需求的元素汞溯源传递方法和形成元素汞发生器溯源传递能力提供借鉴.     

Assessment of trace elements in animal tissues from Turkey

In this study, trace element contents of animal tissues were determined by atomic absorption spectrometry after microwave digestion method. The accuracy of the method was confirmed by analysis of standard reference material (NIST SRM 1577b Bovine Liver). Trace element contents in animal tissue samples were found in the range of 98.3-18.2 μg/g (Fe), 2.89-0.26 μg/g (Mn), 23.9-4.54 μg/g (Zn), 0.08-0.01 μg/g (Pb), 32.9-1.66 μg/g (Cu), and 0.32-0.01 μg/g (Cd). The results were compared with literature values. The results obtained for toxic and trace elements in analyzed animal tissue samples were acceptable to human consumption at nutritional and toxic levels.     

The development of stream temperature model in a mountainous river of Taiwan

Formosan landlocked salmon is an endangered species and is very sensitive to stream temperature change. This study attempts to improve a former stream temperature model (STM) which was developed for the salmon’s habitat to simulate stream temperature more realistically. Two modules, solar radiation modification (SRM) and surface/subsurface runoff mixing (RM), were incorporated to overcome the limitation of STM designed only for clear-sky conditions. It was found that daily temperature difference is related to cloud cover and can be used to adjust the effects of cloud cover on incident solar radiation to the ground level. The modified model (STM + SRM) improved the simulation during a baseflow period in both winter and summer with the Nash-Sutcliffe efficiency coefficient improved from 0.37 (by STM only) to 0.71 for the winter and from ?0.18 to 0.70 for the summer. On the days with surface/subsurface runoff, the incorporation of the two new modules together (STM + SRM + RM) improved the Nash-Sutcliffe efficiency coefficient from 0.00 to 0.65 and from 0.29 to 0.83 in the winter and the summer, respectively. Meanwhile, the contributions of major thermal sources to stream temperature changes were identified. Groundwater is a major controlling factor for regulating seasonal changes of stream temperature while solar radiation is the primary factor controlling daily stream temperature variations. This study advanced our understanding on short-term stream temperature variation, which could be useful for the authorities to restore the salmon’s habitat.     

Heavy metal contents of organically produced, harvested, and dried fruit samples from Kayseri, Turkey

Organically produced, harvested, and dried fruit samples bought at organic markets in Kayseri, Turkey have been analyzed for their trace element contents. In the determinations, flame atomic absorption spectrometer (FAAS) was used. This pilot study is the first to be performed for organically produced, harvested, and dried fruit samples from Kayseri, Turkey. The copper, iron, manganese, and zinc concentrations were found to be 1.6–15.5, 10.3–144, 23.0–211, and 23.3–91.6 μg/g, respectively. The cobalt, lead, cadmium, chromium, and nickel concentrations in all analyzed organic fruit samples were below the quantification limits of FAAS. SRM 1570A spinach leaves and SRM 1515 apple leaves were used to check the accuracy of the procedure. The results for the dried fruit samples found in this work were compared with the values from some studies from the world. The results found in the presented work may also be useful for future studies about organically produced, harvested, and dried fruit samples.     

QuEChERS-GC/ECD法分析土壤和沉积物中残留有机氯农药和多氯联苯

建立了用快速、简单、廉价、有效、可靠及安全(Qu ECh ERS)的方法净化、GC/ECD法测定沉积物中有机氯农药和多氯联苯的分析方法。目标化合物质量浓度在1.0~100μg/L范围内线性良好,相关系数均0.999,检出限为0.08~0.17μg/L。以沉积物标准样品SRM1944为研究对象,用Qu ECh ERS方法和传统方法进行提取比较,并用沉积物样品进行验证,回收率为87.8%~100.3%。方法快速、简单、可靠、安全。     

X射线荧光光谱分析空气滤膜颗粒物中多种元素

采用X射线荧光光谱分析空气滤膜采集悬浮颗粒物中的多种元素,样品不需要前处理,不使用试剂,测量1个样品中40余种元素约耗时1 h。重复测量10次NIST SRM 2783空气滤膜标准样品,多数元素的测量值与标准值基本一致,测量值的标准偏差较小;测量20个空气滤膜实际样品,并与ICP-MS法作比对,大多数元素两种方法测量结果的相对偏差较小,测量值基本一致。     

The contribution of roadside soil to phosphorus loading in the eutrophic Lagos Lagoon, Nigeria

Roadside soils were sampled from the Lagos Lagoon catchment during the wet and dry seasons over the period 2005-2009. Lagoon sediment samples were also collected within the same period. All samples were digested with aqua regia to determine total phosphorus and extracted with 0.5 M sodium bicarbonate to determine the bioavailable fraction (Olsen-P). A segmented flow analyser method was used for analysis and good accuracy was demonstrated for two reference soils (SO-2 from CCMET and SRM 2711 from NIST). The Lagos Lagoon is a hypereutrophic water body (1270 ± 1170 μg P L(-1)), with significant areas of anoxia and water hyacinth growth. The total phosphorus concentrations in roadside soils (16 sites; mean ± 2 S.D.) were 285 ± 279 mg kg(-1) in the wet season and 424 ± 629 mg kg(-1) in the dry season, indicating that rainwater leaching is a major source of phosphorus in the lagoon. The bioavailable fractions were 5.17 ± 3.47 mg kg(-1) (2.1 ± 1.5% of the total) in the wet season and 13.0 ± 8.7 mg kg(-1) (4.3 ± 4.5% of the total) in the dry season.