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Ultratrace-level determination of N-Nitrosodimethylamine, N-Nitrosodiethylamine, and N-Nitrosomorpholine in waters by solid-phase extraction followed by liquid chromatography-tandem mass spectrometry 固相萃取-液相色谱-串联质谱法测定水中n -亚硝基二甲胺、n -亚硝基二乙胺和n -亚硝基somorpholine
Pub Date : 2014-09-01 DOI: 10.2478/s11532-014-0537-z
Y. Kadmi, L. Favier, I. Soutrel, M. Lemasle, D. Wolbert
N-nitrosamines are a new class of emerging nitrogenous drinking water disinfection by-products. These compounds are probably carcinogenic which could seriously affect the safety of drinking water consumers. The aim of this study is to develop a simple, fast, and specific analytical method for the routine determination of low part per trillion levels of N-nitrosamines in waters. An ultra high pressure liquid chromatography coupled with tandem mass spectrometry (UHPLC/MS/MS) method was developed for the qualitative and quantitative analysis of N-nitrosamines in waters. N-nitrosamines were extracted, purified and concentrated from water samples in one step using a solid-phase extraction (SPE). The compounds were detected in multiple reaction monitoring via electrospray ionisation source with positive ionisation mode. To achieve symmetrical peak shapes and a short chromatographic analysis time, the mobile phase consisting of acetonitrile, water and formic acid (60:40:0.1, v/v/v) was used in the experiment. Chromatographic separation of N-nitrosamines was done in less than two minutes. All calibration curves had good linearity (r2≥ 0.9989). The intra- and inter-day precision of the assay ranged from 0.59% to 3.11% and accuracy ranged from 99.66% to 104.1%. The mean recoveries of N-nitrosamines in spiked water were 98%-101%. The reproducability was acceptable with relative standard deviations of less than 3.53%. The proposed method yielded detection limits very low which ranges from 0.04 to 0.16 ng L−1. Finally, the developed analytical method was successfully applied to the analysis of N-nitrosamines in natural water sample
n -亚硝胺是一类新兴的含氮饮用水消毒副产物。这些化合物可能具有致癌性,会严重影响饮用水消费者的安全。本研究的目的是建立一种简单、快速、特异的分析方法,用于常规测定水中低万亿分之一水平的n -亚硝胺。建立了超高压液相色谱-串联质谱法(UHPLC/MS/MS)对水体中n -亚硝胺进行定性和定量分析的方法。采用固相萃取法(SPE)一步提取、纯化和浓缩水样中的n -亚硝胺。采用电喷雾电离源,采用正电离模式对化合物进行多反应监测。为了达到峰形对称和色谱分析时间短,实验采用乙腈、水和甲酸(60:40:1 . 0,v/v/v)为流动相。n -亚硝胺的色谱分离在不到两分钟的时间内完成。所有校准曲线线性良好(r2≥0.9989)。日内、日间精密度为0.59% ~ 3.11%,准确度为99.66% ~ 104.1%。n -亚硝胺在加样水中的平均回收率为98% ~ 101%。重现性可接受,相对标准偏差小于3.53%。该方法的检测限非常低,范围为0.04至0.16 ng L−1。最后,将所建立的分析方法成功地应用于天然水样中n -亚硝胺的分析
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引用次数: 17
Removal of zinc ions as zinc chloride complexes from strongly acidic aqueous solutions by ionic exchange 离子交换法去除强酸性水溶液中锌离子作为氯化锌络合物的研究
Pub Date : 2014-08-01 DOI: 10.2478/s11532-014-0504-8
Emilia Gîlcă, A. Măicăneanu, P. Ilea
The aim of this study was to compare several anion exchangers and to investigate the capacity of Amberlite IRA410 to remove zinc as chloride [ZnCl3]− from hydrochloric solutions (1 M). Influence of the process parameters such as stirring rate, resin quantity and zinc initial concentration over the removal process, was considered. The highest experimental ionic exchange capacity between the considered anionic exchangers, in the same working conditions (500 rpm, 5 g resin and 500 mg L−1), was obtained for Amberlite IRA410, 8.34 mg g−1. With an increase of zinc ions concentration, ionic exchange capacity increased up to 19.31 mg g−1 (1100 mg L−1). The experimental data were analysed using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. The results were also analyzed using sorption kinetics models, pseudo-first-, pseudo-second-order, intra-particle and film diffusion models. From the Dubinin-Radushkevich and Temkin isotherm models the mean free energy and heat of sorption were calculated to be 7.45 kJ mol−1, respectively 1×10−4 kJ mol−1, which indicates that zinc sorption is characterized by a physisorption process. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model.
本研究的目的是比较几种阴离子交换剂,并研究Amberlite IRA410从盐酸溶液(1m)中以氯化锌[ZnCl3]−的形式去除锌的能力。研究了搅拌速率、树脂用量和锌的初始浓度等工艺参数对去除过程的影响。在相同的工作条件下(500 rpm, 5 g树脂和500 mg L−1),Amberlite IRA410的实验离子交换容量最高,为8.34 mg g−1。随着锌离子浓度的增加,离子交换容量增加到19.31 mg g−1 (1100 mg L−1)。实验数据采用Langmuir、Freundlich、Temkin和Dubinin-Radushkevich等温线模型进行分析。采用吸附动力学模型、伪一阶、伪二阶、颗粒内和膜内扩散模型对结果进行了分析。根据Dubinin-Radushkevich和Temkin等温线模型计算出锌吸附的平均自由能和平均吸附热分别为7.45 kJ mol−1 1×10−4 kJ mol−1,表明锌的吸附是物理吸附过程。动力学研究表明,吸附符合准二级动力学模型。
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引用次数: 12
Polyphenols in Coreopsis tinctoria Nutt. fruits and the plant extracts antioxidant capacity evaluation 山茱萸中的多酚类物质。水果及植物提取物抗氧化能力评价
Pub Date : 2014-08-01 DOI: 10.2478/s11532-014-0539-x
C. Zălaru, C. C. Crisan, I. Călinescu, Z. Moldovan, Isabela Tarcomnicu, S. Lițescu, R. Tatia, L. Moldovan, D. Boda, M. Iovu
The aim of this research was to investigate the chemical composition of Coreopsis tinctoria Nutt. fruits extract, to highlight the potential of ultrasound assisted extraction in the fast preparation of extracts rich in polyphenols using different solvents (55%, 78% and 96% hydrous ethanol) and to evaluate the antioxidant potential of formulated extracts. LC-MS/MS was used to characterize the ethanolic extract from Coreopsis tinctoria Nutt. dried fruits. The extract contains different flavonoids (marein, flavanomarein, quercetagetin-7-O-glucoside, okanin aurone, leptosidin, luteolin, apigenin) and phenolic acids (chlorogenic acid, caffeic acid). Several parameters that could affect extraction efficiency were evaluated. Finally, this study focused on determination of plant extracts total phenolic content and their antioxidant capacity. The experimental results allowed the selection of the optimum operating parameters leading to the highest total polyphenolic content, expressed as gallic acid equivalents, and avoiding the degradation of phenolic compounds (ethanol 55%; extraction temperature 323.15 K, extraction time 30 min, liquid/solid ratio 20/1). A good relationship between total phenolic content and antioxidant capacity was obtained.
摘要本研究的目的是研究黄菖蒲的化学成分。研究了超声辅助提取在不同溶剂(55%、78%和96%的含水乙醇)下快速制备富含多酚的提取物中的潜力,并评价了配方提取物的抗氧化潜力。采用液相色谱-质谱联用技术(LC-MS/MS)对Coreopsis tinctoria Nutt乙醇提取物进行表征。干果。该提取物含有不同的黄酮类化合物(马柳苷、黄柳苷、槲皮素-7- o -葡萄糖苷、山核桃素、金酮、瘦素、木犀草素、芹菜素)和酚酸(绿原酸、咖啡酸)。对影响提取效率的几个参数进行了评价。最后,对植物提取物的总酚含量及其抗氧化能力进行了研究。实验结果允许选择最佳操作参数,从而获得最高的总多酚含量,以没食子酸当量表示,并避免酚类化合物(乙醇55%;提取温度323.15 K,提取时间30 min,液固比20/1)。总酚含量与抗氧化能力之间存在良好的关系。
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引用次数: 30
AlZn based Co and Ni catalysts for the partial oxidation of bioethanol — influence of different synthesis procedures AlZn基Co和Ni催化剂对生物乙醇部分氧化的影响-不同合成工艺的影响
Pub Date : 2014-06-07 DOI: 10.2478/s11532-014-0573-8
H. Ehrich, E. Kraleva
The catalytic performance of Co and Ni catalysts on AlZn mixed oxide supports depends on the synthesis procedure used for their preparation. For this study CoAlZn and NiAlZn catalysts were prepared by conventional sol-gel synthesis of the mixed oxide and subsequent impregnation of the support with the transition metal (SG = sol gel method) as well as by a single-step method were a gel is formed based on salts of all components using citric acid as chelating agent (CM = citrate method). The structure and morphology of the catalysts were characterized by nitrogen sorption, XRD and TPR measurements. They showed high activity in the partial oxidation of ethanol at 600–750 °C, but their properties depend on the preparation method. The higher performance of the catalysts prepared by the citrate method, where the transition metal is incorporated into the crystal structure of the support during preparation, is based on a change in morphology and structure, resulting in more active sites exposed on the surface. Compared to the Co catalysts, Ni catalysts showed a higher performance. This might be due to the higher reducibility and the smaller Ni particles size, which allows a better interaction with the support in NiAlZn catalysts.
Co和Ni催化剂在AlZn混合氧化物载体上的催化性能取决于其制备的合成工艺。本研究采用常规的混合氧化物溶胶-凝胶合成法,然后用过渡金属浸渍载体(SG =溶胶-凝胶法),以及采用柠檬酸作为螯合剂(CM =柠檬酸盐法),用所有组分的盐形成凝胶的单步法制备了CoAlZn和NiAlZn催化剂。通过氮吸附、XRD和TPR测试对催化剂的结构和形貌进行了表征。在600 ~ 750℃条件下,它们对乙醇的部分氧化表现出较高的活性,但其性能与制备方法有关。柠檬酸盐方法制备的催化剂性能更高,在制备过程中过渡金属被纳入载体的晶体结构中,是基于形态和结构的变化,导致更多的活性位点暴露在表面上。与Co催化剂相比,Ni催化剂表现出更高的性能。这可能是由于更高的还原性和更小的Ni颗粒尺寸,这使得在NiAlZn催化剂中与载体有更好的相互作用。
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引用次数: 5
Recent progress in the application of glow-discharge electrolysis plasma 辉光放电电解等离子体的应用进展
Pub Date : 2014-06-07 DOI: 10.2478/s11532-014-0575-6
Jie Ren, M. Yao, Wu Yang, Yan Li, Jinzhang Gao
Non-equilibrium plasma makes it is possible to modify surface chemistry, synthetize polymer materials, and oxidize some organic compounds completely by generation of energetic and chemically active species in gas or liquid phases. Glow-discharge electrolysis plasma (GDEP) has been intensely studied for applications in chemistry and in material, environmental, and biomedical engineering during the last few years because of the very highly active chemical species produced during the glow-discharge electrolysis (GDE) process. A brief review is already available regarding applications of glow-discharge electrolysis plasma technique in chemistry and environmental science during the past decade. For convenience of discussion, some papers from prior years are also cited. The contents of this review are focused on the degradation of persistent pollutants, surface modification of materials, and preparation of functional polymers.
非平衡等离子体可以通过在气相或液相中产生能量和化学活性物质来修饰表面化学,合成高分子材料和完全氧化某些有机化合物。辉光放电电解等离子体(GDEP)由于在辉光放电电解(GDE)过程中产生非常高活性的化学物质,近年来在化学、材料、环境和生物医学工程等领域的应用得到了广泛的研究。本文对近十年来辉光放电电解等离子体技术在化学和环境科学中的应用作了简要综述。为了讨论方便,也引用了往年的一些论文。本文就持久性污染物的降解、材料的表面改性以及功能聚合物的制备等方面进行了综述。
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引用次数: 21
Kinetic study of wood pyrolysis in presence of metal halides 金属卤化物存在下木材热解动力学研究
Pub Date : 2014-06-07 DOI: 10.2478/s11532-014-0577-4
Vladimir A. Beliy, E. Udoratina
The purpose of this work was to study the kinetics of wood pyrolysis in the presence of inorganic salts, representatives of classes of alkali and alkaline earth metal halides (NaCl, KCl, KBr, CaCl2, BaCl2·2H2O) and Lewis acids (AlCl3·6H2O, FeCl3·6H2O, CuCl2, CuBr2, ZnCl2·1.5H2O, NiCl2·6H2O, SnCl2·2H2O) using TG-DSC. The activity of these catalysts was estimated by the temperature of the beginning of pyrolysis, charcoal yield and kinetic parameters, such as energy of activation and reaction order. Using the Lewis acids as catalysts for pyrolysis leads to a decrease in the temperature of the process beginning and the activation energy. In the presence of other catalysts activation energy does not significantly change. The increase of a seeming reaction order in the presence of Lewis acids possibly is a consequence of complication of the thermodestruction mechanism, with the appearance of new parallel competing stages.
本研究的目的是利用TG-DSC研究木材在无机盐、碱金属卤化物(NaCl、KCl、KBr、CaCl2、BaCl2·2H2O)和路易斯酸(AlCl3·6H2O、FeCl3·6H2O、CuCl2、CuBr2、ZnCl2·1.5H2O、NiCl2·6H2O、SnCl2·2H2O)存在下的热解动力学。通过热解起始温度、炭产率和活化能、反应顺序等动力学参数来评价催化剂的活性。采用Lewis酸作为催化剂,可以降低热解起始温度和活化能。在其它催化剂的存在下,活化能没有明显变化。在路易斯酸的存在下,表面上反应级数的增加可能是热破坏机制复杂化的结果,出现了新的平行竞争阶段。
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引用次数: 10
Biosorption of toxic metals using freely suspended Microcystis aeruginosa biomass 自由悬浮铜绿微囊藻生物量对有毒金属的生物吸附
Pub Date : 2014-06-07 DOI: 10.2478/s11532-014-0576-5
P. Rzymski, P. Niedzielski, J. Karczewski, B. Poniedziałek
This paper describes the potential application of a freely suspended cyanobacterial biomass of Microcystis aeruginosa as a sorption material for toxic metals, cadmium (Cd) and lead (Pb) from aqueous solutions. In order to identify the most suitable conditions for removal of these elements (concentration range: 1–20 mg L−1), the laboratory experiments were carried out during different incubation times (1–48 h) and under various temperatures (10–40°C), pH (5–9) and with or without light irradiance. Competitive biosorption of Cd and Pb was also investigated. We found that M. aeruginosa demonstrates high efficiency in removing both of the studied metals from aqueous solutions. Sorption of Pb occurred, however, more rapidly and effectively, and was less disturbed by changes in physico-chemical conditions. Under pH=7, 25°C and light, the removal rates after 3 h and 6 h of incubation, were 90–100% for Pb and 79.5–100% for Cd, respectively. The co-occurrence of the metals decreased the rate of metal biosorption. Pb was sequestered preferentially over Cd. From the results we conclude that freely suspended M. aeruginosa can constitute a promising low-cost, easy-producible biosorbent material for toxic metals in contaminated wastewater.
本文介绍了铜绿微囊藻(Microcystis aeruginosa)自由悬浮蓝藻生物量作为水溶液中有毒金属镉(Cd)和铅(Pb)的吸附材料的潜在应用。为了确定去除这些元素的最合适条件(浓度范围:1 - 20 mg L−1),在不同的孵育时间(1 - 48 h)、不同的温度(10-40°C)、pH(5-9)和光照或不光照下进行了实验室实验。对镉和铅的竞争性生物吸附也进行了研究。我们发现铜绿假单胞菌对这两种金属的去除率很高。然而,铅的吸附速度更快,效果更好,受物理化学条件变化的干扰较小。在pH=7、25℃和光照条件下,培养3 h和6 h后,对Pb和Cd的去除率分别为90-100%和79.5-100%。金属的共存降低了金属的生物吸附速率。结果表明,自由悬浮的M. aeruginosa可作为一种低成本、易生产的吸附废水中有毒金属的生物吸附材料。
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引用次数: 18
Voltammetric behavior and quantitative determination of ambazone concentrations in urine and in a pharmaceutical formulation 尿中和制剂中氨bazone浓度的伏安行为和定量测定
Pub Date : 2014-06-07 DOI: 10.2478/s11532-014-0574-7
S. Smarzewska, Dariusz Guziejewski, M. Skowron, S. Skrzypek, W. Ciesielski
The use of square wave adsorptive stripping voltammetry (SWAdSV) in conjunction with a cyclic renewable silver amalgam film electrode (Hg(Ag)FE) for the analytical determination of ambazone in urine samples and pharmaceutical formulations is described. A single reduction peak in Britton-Robinson buffer at pH 4.0 was detected at about −1.4 V versus Ag/AgCl. Mechanistic studies have shown that the compound can act as an electrocatalyst. The method was validated. The analytical curve was linear in the concentration range from 1.0×10−9 to 1.0×10−7 mol L−1. The detection and quantification limits were found to be 3.0×10−10 mol L−1 and 1.0×10−9 mol L−1, respectively. The proposed method was successfully applied to ambazone determination in real samples.
本文描述了方波吸附溶出伏安法(SWAdSV)与循环可再生银汞合金薄膜电极(Hg(Ag)FE)联合用于尿液样品和药物配方中氨bazone的分析测定。在pH为4.0的布列顿-罗宾逊缓冲液中,在约−1.4 V时检测到Ag/AgCl的单个还原峰。机理研究表明,该化合物可作为电催化剂。对该方法进行了验证。浓度在1.0×10−9 ~ 1.0×10−7 mol L−1范围内呈线性关系。检测限和定量限分别为3.0×10−10 mol L−1和1.0×10−9 mol L−1。该方法可用于实际样品中氨bazone的测定。
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引用次数: 11
Editorial preface for the special issue “Catalysis for Renewable Sources: Fuel, Energy, Chemicals” 特刊“可再生能源的催化:燃料、能源、化学品”社论序言
Pub Date : 2014-06-07 DOI: 10.2478/S11532-014-0578-3
V. Yakovlev
FOR RENEWABLE SOURCES: FUEL, ENERGY, CHEMICALS (CRS-2) was held on July 22-28, 2013 at the old university town Lund, situated in the southern Sweden. The First conference CRS-1 took place in St. Petersburg on 2010, and had a great response as an event which demonstrated a high interest to the highly actual and developing trends in science and technology. The First conference collected about 200 participants from 27 countries all over the world. Among the conference organizers were Missouri University of Science and Technology, USA and Petrobras, Brazil. The selection of CRS-2 venue was based on the intensive development of biochemical technology in Scandinavia and on the opportunity to visit the power plants, as well as the objects on production and of the biological materials, the products of fine and organic synthesis from renewable raw materials in Sweden and other neighboring countries. The Lund University was the co-organizer of the conference; the members of the Chemical Technology faculty of the University actively participated in the scientific program of the CRS-2. The conference was devoted to a discussion of the fundamental approaches to the processes of catalytic processing of plant renewable raw materials. The main objective of this discussion is the solution of the most important and especially actual problems today the complex and deep processing of vegetable raw materials to obtain valuable chemicals and fuels. The use of the renewable resources for energy can not only reduce the growth of consumption of traditional fossil fuels, but also reduce human impacts on the environment, including carbon dioxide emissions. Much attention was paid to the discussion of the pyrolysis, gasification, and fermentation technologies for the production of biofuels. The emphasis was made on catalytic methods to address these issues. CRS-2 conference was attended by about 100 participants from 28 countries. The conference program included seven plenary lectures, five keynote presentations, 38 oral and 30 poster presentations. The Plenary session was opened by a recognized expert in the field of chemical engineering from Sweden, Professor Jan Brandin (Linnaeus University). He presented an overview lecture on the current state of development of the new technologies for energy production from renewable raw materials, processes, deep processing of plant materials in Sweden. Traditionally, much attention was attracted by the lecture of one of Russia’s leading scientists in the field of biotechnology, director of the Institute of Biochemical Physics. NM Emanuel, Professor S.D. Varfolomeev. He spoke about the current approaches to the solution of technological problems waste into energy and fuels. The lecture by Professor Tapio Salmi (Åbo Akademi University, Turku, Finland) was devoted to the application of the principles of chemical engineering for low temperature biomass conversion. Interesting results was showed by Professor Jean Carlos SerranoCentral Eu
2013年7月22日至28日,可再生能源:燃料、能源、化学品(CRS-2)在瑞典南部的老大学城隆德举行。第一届CRS-1会议于2010年在圣彼得堡举行,作为一个对科学技术的高度实际和发展趋势表现出高度兴趣的事件,得到了很大的反响。第一届会议聚集了来自世界27个国家的约200名与会者。会议的组织者包括美国密苏里科技大学和巴西国家石油公司。CRS-2场地的选择是基于斯堪的纳维亚生化技术的密集发展,并有机会参观发电厂,以及瑞典和其他邻国的生物材料,可再生原料精细和有机合成产品的生产和对象。隆德大学是这次会议的协办方;我校化工系教师积极参与CRS-2科研项目。会议专门讨论了植物可再生原料催化加工过程的基本方法。本次讨论的主要目的是解决当今最重要和特别实际的问题,即对蔬菜原料进行复杂的深加工,以获得有价值的化学品和燃料。利用可再生资源作为能源,不仅可以减少传统化石燃料消费的增长,还可以减少人类对环境的影响,包括二氧化碳的排放。重点讨论了生物燃料的热解、气化和发酵技术。重点讨论了解决这些问题的催化方法。来自28个国家的约100名代表出席了CRS-2会议。会议计划包括7场全体演讲、5场主题演讲、38场口头演讲和30场海报演讲。全体会议由瑞典化学工程领域公认的专家Jan Brandin教授(林奈大学)主持开幕。他就瑞典利用可再生原料、工艺、植物材料深加工生产能源的新技术的发展现状作了概述讲座。传统上,俄罗斯生物技术领域的顶尖科学家之一、生物化学物理研究所所长的演讲吸引了很多注意力。NM Emanuel, S.D. Varfolomeev教授。他谈到了目前将废物转化为能源和燃料的技术问题的解决方法。Tapio Salmi教授(Åbo芬兰图尔库学术大学)的讲座专门讨论了化学工程原理在低温生物质转化中的应用。Jean Carlos serra教授在《中欧化学杂志》上发表了有趣的研究结果
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引用次数: 1
Geochemical investigation of alluvial sediments: validation of ICP-OES determination of heavy metals. A case study from the Utrata River Valley (central Poland) 冲积沉积物的地球化学研究:ICP-OES测定重金属的验证。乌特拉塔河谷(波兰中部)案例研究
Pub Date : 2014-06-01 DOI: 10.2478/s11532-014-0520-8
M. Biro, Darja Kavšek, J. Karasiński, P. Szwarczewski, E. Bulska, D. Vončina
The development and validation of a reliable analytical procedure for the determination of selected metals (Cd, Cr, Cu, Pb, Zn and Mn) in sediments accumulated in the Utrata River (Poland) is described. The aqua regia extraction followed by inductively coupled plasma optical emission spectrometry (ICP-OES) was used for this purpose. The optimized analytical procedure was validated, and adequate quality control actions were implemented in order to provide reliable data. The precision under’ within-laboratory’ reproducibility conditions was estimated from duplicate analysis. Certified reference material (CRM) was used in order to evaluate the accuracy of the results regarding the sewage sludge amended soil CRM 143R. The detection limits for all elements of interest were well-below their content in the investigated sediment samples. The obtained reliable data could be used for assessment of the relationship between human economic activity in the past and the geochemical features of the sediments.
描述了一种可靠的分析方法的开发和验证,用于测定乌特拉塔河(波兰)沉积物中选定的金属(Cd, Cr, Cu, Pb, Zn和Mn)。采用王水萃取后电感耦合等离子体发射光谱法(ICP-OES)测定。验证了优化的分析方法,并实施了充分的质量控制措施,以提供可靠的数据。“实验室内”重现性条件下的精密度由重复分析估计。采用标准物质(CRM)对污水污泥改性土壤CRM 143R测定结果的准确性进行了评价。所有感兴趣的元素的检出限都远低于所调查的沉积物样品中的含量。所获得的可靠数据可用于评价过去人类经济活动与沉积物地球化学特征之间的关系。
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引用次数: 9
期刊
Central European Journal of Chemistry
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