Co—PADAP分光光度法测定水中微量阴离子表面活性剂

随着合成洗涤剂应用日趋广泛,其主要成份阴离子表面活性剂对环境和生态的影响愈益受到人们的关注.目前测定水中阴离子表面活性剂的国家标准方法是亚甲兰分光光度法,该法操作繁琐,准确度差,易受各种共存物的影响,而且灵敏度低,最低检测浓度仅为0.05mg/L,难以满足残留量的测定要求.近年来,国外曾用Co-PADAP分光光度法测定水中阴离子表面活性剂.本文对此进行了初步试验.经实验证明,本法简便、灵敏,最低检测浓度为0.02mg/L,干扰少,有良好的准确度和重现性.     

高效液相色谱法直接测定环境水体中直链烷基苯磺酸钠类阴离子表面活性剂

使用亚甲蓝分光光度法和流动注射法分析环境水体中的阴离子表面活性剂的过程中用到的三氯甲烷会带来次生环境污染问题,同时也会在一定程度上影响检测人员的健康。结合现有仪器设备,通过优化检测流程,建立了一种适用于高海拔条件下测定环境水体中直链烷基苯磺酸钠(LAS)类阴离子表面活性剂的方法。该方法以十二烷基苯磺酸钠(SDBS)为定量标准物质,采用高效液相色谱法测定,使用归一化法定量。经验证,在0.02~2.00 mg/L浓度范围内,所建立校准曲线的线性回归系数在0.999以上。该方法具有良好的检出能力(检出限为0.01 mg/L)和抗干扰能力,重复性范围为1.3%~6.2%,准确度范围为2.1%~4.0%,回收率范围为80.0%~116%,相关验证参数均能满足实际样品的分析要求。检测过程避免了二次污染物的产生,减少了对实验人员健康的影响。该方法具有操作简便、高效且对环境友好的特点。     

荧光光度法测定地表水中阴离子表面活性剂

采用荧光光度法测定地表水中烷基苯磺酸盐类阴离子表面活性剂,讨论了pH值和干扰物质对测定的影响。方法在0.200 mg/L~5.00 mg/L范围内线性良好,检出限为0.081 mg/L,实际水样加标回收率为98.6%~101%。     

溴甲酚紫-十八烷基二甲基苄基氯化铵分光光度法测定水中阴离子表面活性剂

建立了溴甲酚紫(BCP)-十八烷基二甲基苄基氯化铵(SDMBA-Cl)分光光度法测定水中阴离子表面活性剂的方法.实验表明,最适合的pH值为8左右,λmax=588nm,在1.0ml1.6×10-4mol/LSDMBA-Cl存在下,十二烷基苯磺酸钠(LAS)在0～5.0 mg/L内符合比耳定律,其摩尔吸光系数为4×104L·mol-1·cm-1.用此法测定河水和废水中的阴离子表面活性剂,相对标准偏差＜3.8%,样品加标平均回收率为100.3%.     

分光光度法测定水中十六烷基三甲基溴化铵

基于甲基橙(MO)在水体中和阳离子表面活性剂发生的褪色反应,采用分光光度法测定十六烷基三甲基溴化铵(CTAB),优化了试验条件,讨论了干扰物质的影响。MO与CTAB在10%乙醇-水溶液中反应形成淡黄色离子缔合物,以MO的最大吸收波长470 nm为测定波长,CTAB质量浓度在0 mg/L～13.1 mg/L范围内遵守朗伯-比尔定律,吸光系数为17.48 L/(g.cm),方法检出限为0.364 mg/L,标准溶液平行测定的RSD为2.3%,样品加标回收率为91.8%～107%。     

巯基棉分离富集-偶氮氯膦Ⅲ-TPB-共振光散射测定垃圾渗滤液中的Zn(Ⅱ)

建立了测定垃圾渗滤液中微量Zn(Ⅱ)的巯基棉分离富集-偶氮氯膦Ⅲ-溴代十六烷基吡啶(TPB)共振光散射新方法。在pH为3.1~4.6的Tris-盐酸缓冲介质及TPB存在下,Zn(Ⅱ)与偶氮氯膦Ⅲ-TPB结合生成三元缔合物,使共振光散射(RLS)显著增强并产生新的散射光谱,最大RLS散射峰位于378 nm处,体系的RLS增强程度(△IRLS)与0.008~0.20 mg/L范围内的Zn(Ⅱ)呈线性关系,定量限为0.010 mg/L。研究了共振光散射的光谱特征、适宜的反应条件及主要分析化学性质。方法用于垃圾填埋场渗滤液中Zn(Ⅱ)的测定,加标回收率为98.10%~102.7%,相对标准偏差为1.5%~1.8%。     

离子色谱法测定丙烯酸丁酯生产废水中丙烯酸和对甲基苯磺酸

建立了用离子色谱法测定丙烯酸丁酯生产废水中丙烯酸和对甲基苯磺酸的新方法。采用IonPac AS11-HC阴离子色谱柱,淋洗液为30mmol/L的NaOH淋洗液,流速1ml/min,抑制电流75mA。丙烯酸根的检测下限为0.44mg/L(峰面积)、0.46mg/L(峰高),保留时间、峰高、峰面积的变异系数分别为0.03%、0.50%、0.50%,峰高、峰面积的线性回归系数R分别为0.9929、0.9954。对甲基苯磺酸根的检测下限为0.49mg/L(峰面积)、0.48mg/L(峰高),保留时间、峰高、峰面积的变异系数分别为0.02%、0.48%、0.47%,峰高、峰面积的线性回归系数R分别为0.9990、0.9998。常规无机阴离子对丙烯酸、对甲基苯磺酸的测定没有干扰。对实际废水样品进行分析,丙烯酸、对甲基苯磺酸的回收率分别为101.6%～104.4%、95.4%～96.8%。方法简便、灵敏、可靠。     

印染废水中阴离子表面活性剂(AD)的电极法测定

本文以氧化分解一电位滴定法测定印染废水中阴离子表面活性剂的含量。预处理方法简便、快速、对多数染料干扰的消除是有效的。测定的最低含量为4—5 mg/l,测定实际度水样,变异系数<2％,加标回收率>91％,与亚甲兰方法对照,相对误差～2％。     

水中阴离子表面活性洗涤剂测定新方法的研究

介绍了水中阴离子表面活性剂测定新方法，该法与亚甲蓝法比较，具有操作步骤简单，萃取剂用量少的优点。     

荧光法测定微量硫酸盐的研究

研究了钪与桑色素形成的络合物在紫外光照射下产生淡绿色荧光,受硫酸根的影响而减弱,其荧光强度的降低量与硫酸根浓度成线性关系,据此建立了一个简便测定微量硫酸根的方法,适宜的测定范围为0～1.6mg/L SO_4~(2-),文中还研究了某些阳离子和阴离子的干扰影响及其消除,最后将本法应用于地热水、自来水、泉水、海水和一些分析纯化学试剂中微量硫酸盐的测定,方法灵敏、简便、快速,结果满意。     

Spectrophotometric determination of anionic surfactants: optimization by response surface methodology and application to Algiers bay wastewater

A simple analytical method for quantitative determination of an anionic surfactant in aqueous solutions without liquid-liquid extraction is described. The method is based on the formation of a green-colored ion associate between sodium dodecylbenzenesulfonate (SDBS) and cationic dye, Brilliant Green (BG) in acidic medium. Spectral changes of the dye by addition of SDBS are studied by visible spectrophotometry at maximum wave length of 627 nm. The interactions and micellar properties of SDBS and cationic dye are also investigated using surface tension method. The pH, the molar ratio ([BG]/[SDBS]), and the shaking time of the solutions are considered as the main parameters which affect the formation of the ion pair. Determination of AS in distilled water gives a significant detection limit up to 3?×?10^?6?M. The response surface methodology (RSM) is applied to study the absorbance. A Box-Behnken is a model designed to the establishment of responses given by parameters with great probability. This model is set up by using the three main parameters at three levels. Analysis of variance shows that only two parameters affect the absorbance of the ion pair. The statistical results obtained are interesting and give us real possibility to reach optimum conditions for the formation of the ion pair. As the proposed method is free from interferences from major constituents of water, it has been successfully applied to the determination of anionic surfactant contents in wastewaters samples collected from Algiers bay.     

胶团强化超滤处理水中阿特拉津的研究

采用胶团强化超滤去除水中阿特拉津.考察了表面活性剂、pH、操作压力、操作时间以及温度对阿特拉津去除效果的影响.结果表明,胶团强化超滤法能有效去除水中阿特拉津,最佳工艺条件为:采用分子量为5 000 Dalton的聚砜中空纤维膜、SDBS浓度为8.00mmol/L、压力为0.15 MPa、pH为10、温度为25℃.在此条...     

共振光散射技术在环境分析中的应用

共振光散射技术是一项在普通荧光分光光度计上进行测量的光散射技术,文章简要介绍了光散射现象,共振光散射的基本原理并作了定量基础讨论,对共振光散射技术在环境分析中的应用作了初步研究。     

Enhancement of natural radionuclides in the surroundings of the four largest coal-fired power plants in Spain

The production of electricity in coal-fired power plants (CFPP) is considered a NORM (Naturally Occurring Radioactive Materials) activity because the coals they burn can present relatively high contents of the naturally occurring radionuclides. In this study, the main radiological impact pathways into the surrounding environments of the four largest coal-fired power plants in Spain were analyzed. These pathways are, first, atmospheric evacuations and wind resuspension and, second, effluent evacuations to nearby rivers or directly to the sea. The atmospheric releases of radionuclides were evaluated by the analyses of soil profiles in the vicinities of the CFPPs. No significant enhancement of radionuclides in the surface soil was observed at the points of maximum deposition of combustion gases, located from 4.3 to 13 km away depending on the considered CFPP. However, an increase of (40)K, (226)Ra, and (232)Th in the surface soils was observed in the first kilometre from the chimney for two CFPPs. This suggested that these radionuclides were released in particulate form. There was also a net influence of the climate in which the CFPPs were located. This was observed in the two CFPPs that were in dry environments, while no increase was observed in the other two, located in more humid environments. The liquid effluents released usually presented an enhancement of dissolved chemical species regarding the initial intake water. Enrichments of the (234,238)U and (226)Ra contents in the water used in the plants' routine procedures were observed, and of (210)Po in the wastewater of just one of the plants. In any case, this enhancement was below the parametric value for the Total Indicative Dose for the hypothetical human consumption of the released waters. As a consequence of these releases of radionuclides, local products destined for human consumption produced in the vicinity of the facilities might incorporate natural radionuclides by these pathways, finding no significant enhancement of the natural radionuclide contents due to the CFPPs.     

On the intensity and type transition of land use at the basin scale using RS/GIS: a case study of the Hanjiang River Basin

The purpose of this study is to investigate the land use intensity and land use change type at the basin scale in the middle and lower reaches of the Hanjiang River Basin (in Hubei Province, China) by combining the Landsat TM images in 1995 and 2000 with the land use database (in scale 1:10,000) and relative data. In this study, the basic data is acquired from the interpretation of remote sensing (RS) images. The intensity of land use and the rate of change in double-directions of land use dynamics are calculated with the support of software ARC/INFO. The intensity of land use is indicated by the intensity coefficient of land use, and the transition of land use types is quantified as the rate of change in double-direction of land use types and also expressed as the transition matrix of land use types. The results are expressed in space by Geographic Information System (GIS) software. Results of this study show that (1) the intensity of land use is high in the study region, the intensity coefficients of land use in 1995 and 2000 are 260.025 and 290.526, respectively, and the intensity of development and utilization of land is trend to increscent; and (2) the rate of land use change in double directions in the whole study region is 0.52 with great spatial variation and the differentiation of land use types. In the differentiation of land use types, the unutilized land (with the rate to 4.391) is developed fast, the grassland (with 2.836) and water area (with 1.664) are disturbed severely, and these changes will influence the eco-environment in the Hanjiang River Basin and all the Yangtze Basin. The rates of the farmland and the woodland are 0.424 and 0.344, respectively, meaning that the fundamentals of regional human-environmental system are relative stable. With this study, we can conclude that (1) the patterns of land use are increasingly changing in the study region, the environmental impacts are escalated on this stage, and the further outcomes are destined to change the stability of the regional human–environmental system; and (2) the most useful method to study the present land use and its change is through the use of the RS/GIS with the land use database (in scale 1:10,000).     

Assessment of PM10 Enhancement by Yellow Sand on the Air Quality of Taipei, Taiwan in 2001

The impact of long-range transport of yellow sand from Asian Continent to the Taipei Metropolitan Area (Taipei) not only deteriorates air quality but also poses health risks to all, especially the children and the elderly. As such, it is important to assess the enhancement of PM₁₀ during yellow sand periods. In order to estimate PM₁₀ enhancement, we adopted factor analysis to distinguish the yellow-sand (YS) periods from non-yellow-sand (NYS) periods based on air quality monitoring records. Eight YS events were identified using factor analysis coupling with an independent validation procedure by checking background site values, examining meteorological conditions, and modeling air mass trajectory from January 2001 to May 2001. The duration of each event varied from 11 to 132 h, which was identified from the time when the PM₁₀ level was high, and the CO and NO _x levels were low. Subsequently, we used the artificial neural network (ANN) to simulate local PM₁₀ levels from related parameters including local gas pollutants and meteorological factors during the NYS periods. The PM₁₀ enhancement during the YS periods is then calculated by subtracting the simulated PM₁₀ from the observed PM₁₀ levels. Based on our calculations, the PM₁₀ enhancement in the maximum hour of each event ranged from 51 to 82%. Moreover, in the eight events identified in 2001, it was estimated that a total amount of 7,210 tons of PM₁₀ were transported by yellow sand to Taipei. Thus, in this study, we demonstrate that an integration of factor analysis with ANN model could provide a very useful method in identifying YS periods and in determining PM₁₀ enhancement caused by yellow sand.     

Elution of p-Dichlorobenzene through compacted soil with alcohol-water mixtures

p-Dichlorobenzene (p-DCB) was eluted through a compacted ferruginous clay with dilute aqueous solutions of methanol, ethanol, n- and i-propanols, and n- and i-butanols. The presence of the alcohols results in very marked increases in the concentrations of p-DCB in the effluents from the clay-packed columns. Flux of p-DCB through the columns increases with increasing chain length of the alcohol, and normal alcohols increase the flux somewhat more than corresponding branched alcohols. Flux increases with increasing mole fraction of the alcohol. Flux enhancement is due almost exclusively to enhancement of the solubility of p-DCB.     

太湖流域果园种植面源氮磷输出强度及其定量评估方法

以太湖流域上游地区无锡阳山地区果园种植典型区域为研究对象,通过现场试验,调查了果园种植面源氮磷输出动态变化过程,计算并分析了氮磷输出强度,构建了果园种植面源氮磷输出强度定量评估模型。结果表明:取样监测期间,果园种植径流及淋溶氮磷指标变化幅度均超过200%;果园种植面源氮磷径流输出强度与其淋溶输出的变化一致,径流总氮的输出强度最高(13.201 kg/hm~2),淋溶硝酸盐输出强度最大(4.077 kg/hm~2);所建立的评估方程能较好地反映降雨量等环境因素对果园种植面源氮磷径流及淋溶输出强度的影响情况,模拟方程的复相关系数均在0.9左右。     

Assessment of cyclodextrin-enhanced extraction of crude oil from contaminated porous media

The purpose of this study was to evaluate the effects of cyclodextrin (CD) on the extraction of Macondo well oil from contaminated porous media over a range of hydroxypropyl-β-CD (HPβCD) concentrations. To our knowledge, this is the first dataset on this type of CD yet assembled for an actual crude oil. The results showed that HPβCD can significantly increase oil extraction efficiency, demonstrated by increasing concentrations of all tested normal alkanes (nC(15)-nC(35)) and polyaromatic hydrocarbons (PAHs) in the aqueous phase with increasing CD concentration. A linear relationship between the extraction enhancement effect and CD concentration were verified experimentally and high correlation coefficients for total PAHs (R(2) = 0.82) and alkanes (R(2) = 0.99) were determined. For a 20% CD solution, 3.13 wt% of alkanes and 32.12 wt% of total PAHs were extracted to the aqueous phase, which was significantly more than what was extracted with water only (0.04% and 0.21% for alkanes and PAHs, respectively). This result shows that the remediation of oil contaminated media can be significantly enhanced through the use of HPβCD solutions in flushing or pump and treat operations to remove sorbed oil. The CD extraction enhancement effect decreases with increasing n-alkane chain length for the carbon number range tested. CD significantly enhanced PAH extraction from sand and the enhancement effect increased in the order of parent compounds < C-1 substituted < C-2 substituted < C-3 substituted for most PAHs tested. This study provides important information to assess the feasibility of using CD as a near-shore agent to enhance the cleanup of oil contaminated porous media.     

Influencing factors of carbon emissions in transportation industry based on CD function and LMDI decomposition model: China as an example

Globally, the transportation industry is one of the leading fields that generate the largest share of greenhouse gas emissions. While undergoing rapid development, countries worldwide aim to solve the problems involved in high energy consumption. Taking China as an example, this paper studies the main factors of carbon emissions in the transport sector and analyses the decoupling states between carbon emission and economic growth, making energy efficiency policies accordingly. In order to better demonstrate the dependence of the economy on the carbon emissions in China's transportation industry comprehensively, combined with the CD production function, this paper develops the decomposition and decoupling technology based on the LMDI approach. Additionally, it quantifies seven effects: energy emission intensity effect, energy structure effect, energy intensity effect, transportation intensity effect, technology state effect, labor input effect and capital input effect. The results show three major points: (1) From 2001 to 2018, the cumulative carbon emissions of China's transportation industry increased by 633.46 million tons, in which the capital input effect is the key factor driving carbon emissions, accounting for 157.70% of the total cumulative increased emissions, followed by energy structure effect at 10.39%. The labor input effect accounted for the smallest proportion at 2.26%. In this case, the technology state effect is the primary factor in restraining carbon emissions. During the study period, it reduced carbon emissions by 292.27 million tons, accounting for 46.14%. To a certain extent, energy intensity effect, transportation intensity effect and energy emission intensity inhibited carbon emissions, representing 16.67%, 5.32% and 2.22%, respectively. (2) During the research period, two decoupling states existed between carbon emissions and economic growth in China's transportation industry, specifically weak decoupling and expansive coupling. (3) The analysis of decomposition and decoupling state of influencing factors of carbon emissions shows that, on the one hand, factors promoting carbon emissions (capital input effect, energy structure effect and labor input effect) hinder the decoupling process. On the other hand, factors restraining carbon emissions (technology state effect, transportation intensity effect, energy intensity effect and energy emission intensity effect) accelerate the decoupling process. The research findings provide a new perspective for achieving carbon emission reduction in the transportation industry and curbing energy consumption growth.