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sequential extraction of Natural Surface Coatings: Comparison with Single Stage extraction and Its Application in Investigating Adsorption Characteristics of Surface Coating Components for Metals

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Chemical Research in Chinese Universities 2012年第1期28卷 41-46页

作者： HUA Xiu-yi, LIU Xiao-xue, DONG De-ming, LI Ming and LI Yao-rui Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Key Lab of Water Resources and Aquatic Environment of Jilin Province, College of Environment and Resources, Jilin University, Changchun 130012, P. R. China College of Environment and Resources Jilin University Key Laboratory of Groundwater Resources and Environment Ministry of Education Key Lab of Water Resources and Aquatic Environment of Jilin Province Changchun 130012

Multistage sequential extraction with different sequences was applied to extracting natural surface coa tings（NSCs）, and the results were compared with those by single stage extraction technique. The optimal sequential extraction scheme with the best performance was selected and incorporated into the method of selective extraction followed by adsorption and statistic analyses to study the adsorption parameters of Fe oxides, Mn oxides and organic matters in NSCs for Pb and Cd, to validate the applicability of the sequential extraction scheme. The Langmuir ad sorption parameters of each component of surface coating estimated according to the adsorption data of single stage extraction of NSCs were all similar to those of sequential extraction of NSCs, and the maximum difference between the metal adsorption abilities of the components estimated via the two extraction techniques was only about 20%, in dicating that either extraction techniques could be used. The optimal sequential extraction scheme obtained was first extracted with NH2OH·HCl, then with Na2S2O4, and finally with oxalic acid.

关键词： Natural surface coating(NSC) sequential extraction Single stage extraction Adsorption Component

sequential extraction of RNA,DNA and protein from cultured cells of the same group

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World Journal of Methodology 2023年第5期13卷 484-491页

作者： Ying-Yu Cui Department of Cell Biology Institute of Medical GeneticsKey Laboratory of Arrhythmias of the Ministry of Education of ChinaTongji University School of MedicineShanghai 200331China

BACKGROUND Efficient extraction of nucleic acids and proteins(ENAP)from cells is a prerequisite for precise annotation of gene function,and has become laboratory routine for revealing the mysteries of ***,cell samples are often from different culture dishes,resulting in inevitable experimental errors and sometimes poor *** To explore a method to improve the efficiency of ENAP,minimizing errors in ENAP processes,enhancing the reliability and repeatability of subsequent experimental *** A protocol for the sequential isolation of RNA,DNA,and proteins from the same cultured HepG2 cells using RNAzol reagent is presented *** first step involves culturing HepG2 cells to the exponential phase,followed by the sequential isolation of RNA,DNA,and proteins from the same cultured cells in the second *** yield of nucleic acids and proteins is detected in the third step,and their purity and integrity are verified in the last *** The procedure takes as few as 3-4 d from the start to quality verification and is highly *** contrast to the existing kits and reagents,which are primarily based on independent isolation,this RNAzol reagent-based method is characterized by the sequential isolation of RNA,DNA,and proteins from the same cells,and therefore saves time,and has low cost and high *** The RNA,DNA,and proteins isolated using this method can be used for reverse transcription-polymerase chain reaction,polymerase chain reaction,and western blotting,respectively.

关键词： sequential extraction Ribonucleic acid Deoxyribonucleic acid Protein Cultured cells

sequential extraction on Oil Sandstones from TZ401 Well-A Case Study on Filling History of Hydrocarbon Reservoir

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Journal of China University of Geosciences 2008年第6期19卷 656-664页

作者：潘长春刘大永 State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences

sequential extraction was performed on two oil sandstones from the Upper Carboniferous oil columns of TZ401 well. The free oils of these two oil sandstones and a crude oil from the Lower Carboniferous oil column of this well have low ratios of C28/（C27 ＋ C28＋ C29） steranes and gammacerane/C31 hopanes, ranging of 0.11-0.16 and 0.09-0.15, respectively, similar to those from the Middle-Upper Ordovician source rock. However, these two ratios for the adsorbed and inclusion oils of these two oil sandstones are relatively high, ranging of 0.29-0.31 and 0.26-0.40, respectively, similar to those of the Cambrian-Lower Ordovician source rock. This result demonstrates that the initial oil charging the reservoirs was derived from the Cambrian-Lower Ordovician source rock, whereas the later charging oil was derived from the Middle-Upper Ordovician source rock.

关键词： sequential extraction oil sandstone oil-bearing fluid inclusion Tarim basin

Sorption mechanisms of diphenylarsinic acid on natural magnetite and siderite:Evidence from sorption kinetics,sequential extraction and extended X-ray absorption fine-structure spectroscopy analysis

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Frontiers of Environmental Science & Engineering 2022年第9期16卷 39-52页

作者： Meng Zhu Yuhuan He Xiaobao Wei Haoran Qi Yunpeng Zhang Yijun Zhang Ruyi Yang Yongming Luo School of Ecology and Environment Anhui Normal UniversityWuhu 241002China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Anhui Provincial Engineering Laboratory of Water and Soil Pollution Control and Remediation Anhui Normal UniversityWuhu 241002China Center of Cooperative Innovation for Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt Anhui Normal UniversityWuhu 241002China

Diphenylarsinic acid(DPAA)is both the prime starting material and major metabolite of chemical weapons(CWs).Because of its toxicity and the widespread distribution of abandoned CWs in burial site,DPAA sorption by natural Fe minerals is of considerable *** we report the first study on DPAA sorption by natural magnetite and siderite using macroscopic sorption kinetics,sequential extraction procedure(SEP)and microscopic extended X-ray absorption fine-structure spectroscopy(EXAFS).Our results show that the sorption pseudo-equilibrated in 60 minutes and that close to 50%and 20%–30%removal can be achieved for magnetite and siderite,respectively,at the initial DPAA concentrations of 4–100 mg/*** sorption followed pseudo-secondary and intra-particle diffusion kinetics models,and the whole process was mainly governed by intra-particle diffusion and chemical *** and EXAFS results revealed that DPAA mainly formed inner-sphere complexes on magnetite(>80%),while on siderite it simultaneously resulted in outer-sphere and inner-sphere *** analysis further confirmed the formation of inner-sphere bidentate binuclear corner-sharing complexes(^(2)C)for *** of these results with previous studies suggests that phenyl groups are likely to impact the sorption capacity and structure of DPAA by increasing steric hindrance or affecting the way the central arsenic(As)atom maintains charge *** results improve our knowledge of DPAA interactions with Fe minerals,which will help to develop remediation technology and predict the fate of DPAA in soil-water environments.

关键词： Diphenylarsinic acid(DPAA) Sorption Magnetite Siderite sequential extraction EXAFS

Assessment of selective sequential extraction procedure for determining arsenic partitioning in copper slag

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Transactions of Nonferrous Metals Society of China 2020年第10期30卷 2823-2835页

作者： Hui-bin ZHANG Yu-zheng HE Jing-jing HU Ya-nan WANG Hua-zhen CAO Jun ZHOU Guo-qu ZHENG College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China Tongling Nonferrous Metals Group Tongling 244000China

An optimized selective sequential extraction(SSE)procedure was developed to assess the arsenic(As)partitioning in copper *** potential As species in copper slag are partitioned into the readily soluble As,dissolvable arsenates,sparingly soluble arsenates,As residing in sulfides,arsenopyrite and metal As,as well as As incorporated into glassy *** inductively coupled plasma atomic emission spectrometry(ICP-AES),scanning electronic microscopy(SEM),transmission electron microscope(TEM),X-ray diffractometry(XRD)and Fourier transform infrared spectroscopy(FTIR)were used to characterize the leachates and residues produced from the operation *** selectivity and recovery of extractants were evaluated through single-phase extraction *** data of As in slag samples show good agreement with the reported works and the total As recovery of each operation is over 90%.This suggests that the optimized SEE scheme can be reliably employed for As partitioning in As-bearing byproducts from copper smelting.

关键词： arsenic copper slag sequential extraction waste management copper smelting

Assessment of heavy metal pollution in sediments from Xiangjiang River(China) using sequential extraction and lead isotope analysis

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Journal of Central South University 2014年第6期21卷 2349-2358页

作者：蒋博峰孙卫玲 Key Laboratory of Water and Sediment Sciences of Ministry of Education(Peking University) Department of Environmental Engineering Peking University

The heavy metal(such as Cr,Ni,Cu,Cd,Pb,and Zn)concentration,speciation,and pollution source in 43 sediment samples from the Xiangjiang River were investigated using sequential extraction combined with Pb isotope ***,Cd,Pb,and Zn concentrations are higher than their background values,while Cr and Ni concentrations are close to *** extraction demonstrates that heavy metals have different fractions,showing different *** w(206Pb)/w(207Pb)ratio increases with decreasing bioavailability in the order of exchangeable

关键词： sediment heavy metals sequential extraction lead isotope

Determination of Heavy Metals in Two Regions from Kirkuk City Using sequential extraction

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Journal of Geoscience and Environment Protection 2016年第2期4卷 38-45页

作者： Kameran Shukur Hussain Nursing College Kirkuk University Kirkuk Iraq

Soil is a major reservoir for heavy metals and other contamination as it possesses an ability to absorb these metals on the surface of clay minerals and bind various chemicals. These heavy metals and chemicals can exist in various forms in soil and different forces keep them bound to clay minerals and soil particles. The aim of the present work is to estimate the concentration levels of some heavy metals Zn, Cu, Pb and Cd in two sites of soil Kirkuk city. In this study the first sample was taken from inside the city of four areas around (Northern Oil Company) in Kirkuk city, while the second sample was taken from outside the city of four areas and both were randomly chosen. sequential extraction procedure was applied to fractionate heavy metals which may help in the prediction of their mobility, bioavailability and fate of the metal contaminant. Results of sequential extraction showed that Cd and Pb were mainly bound to residual fraction, Cu was mainly bound to organic fraction and Zn was bound to Fe-Mn oxide fraction in the two sites of the study. The overall mean values obtained for the metals in the fractions gave the range: inside the city Cu (28.12 ppm), Zn (77.9 ppm), Pb (21.73 ppm) and Cd(4.21 ppm), and outside the city Cu (24.65 ppm), Zn (59.28 ppm), Pb (13.25 ppm) and Cd (2.38 ppm). The extracts were analyzed for heavy metal, using flameless-atomic absorption spectrophotometers (Flameless-AAS).

关键词： Heavy Metals Soil sequential extraction Kirkuk Iraq

Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402,I0007页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China GRIREM Hi–Tech Co. Ltd.Langfang065201China GRIREM Advanced Materials Co. Ltd.Beijing100088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most common mining *** high contents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A comprehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ *** paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and *** results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare *** samples have distinct areas of enrichment for ion-exchangeable rare earths or ***-exchangeable rare earths are primary concentrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micromorphology and particle size of the clay *** inorganic hydroxy aluminum concentration in Chongzuo samples decreases continuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the concentration in Longyan samples(110.55-171.27 mg/kg)is almost independence with sampling *** results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the consumption of leaching agent.

关键词： Weathered crust elution-deposited rare earth ore sequential extraction Occurrence Aluminum Rare earth elements

Heavy Metal Remediation in AgoèNyivéLandfill Soils: Enhancing Stability through Organic Amendments

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Open Journal of Applied Sciences 2024年第4期14卷 961-975页

作者： Bassaï Magnoudéwa Bodjona Diyakadola Dihéénane Bafai Gado Tchangbedji Waste Management Treatment and Valorization Laboratory (GTVD) Faculty of Sciences University of Lom&#233 Lom&#233 Togo

The burial of waste in developing countries, which is often carried out without respect for environmental standards, constitutes a risk of contamination of soils and even groundwater given the toxic elements they contain. The objective of this work is to carry out a study of the retention of heavy metals through the contribution of cattle manure to soil samples from the final Agoè Nyivé landfill in Lomé, Togo. Soil samples from the final landfill were taken from the surface and depth at several locations to form a composite sample. The amendment of the composite sample was carried out with bovine manure on the mock-up in the Laboratory for six months. The determination of the total contents of heavy metals by the atomic absorption spectrophotometer (SAA) on the composite sample showed high contents exceeding the thresholds recommended by the AFNOR NF U 44-041 standard. sequential extraction on these composite samples showed that the mobile portions of lead, cadmium, copper and zinc are respectively estimated at 78.06%, 50%, 28.89% and 91.59%. The bovine manure used to amend the landfill samples presents physicochemical parameters that can contribute to rendering heavy metals immobile in the soil matrix under natural conditions. The addition of manure initially made it possible to increase the values of pH, electrical conductivity, cation exchange capacity and organic matter, which promote the retention of heavy metals. Secondly, the addition of manure made it possible to reduce the mobile portion of the heavy metals studied;from 78.06% to 14.39% for lead, from 50% to 11.52% for cadmium, from 28.89% to almost 0% for copper and from 91.15% to 80.58% for zinc. The use of cattle manure as an amendment on the composite sample was decisive in reducing the mobility of heavy metals in the polluted soils of the final landfill.

关键词： Pollution Heavy Metals Soil sequential extraction Discharge