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  1. Article ; Online: Double Spike-Standard Addition Technique and Its Application in Measuring Isotopes

    Lu, Zhuo / Zhu, Jian-Ming / Tan, Decan / Johnson, Thomas M. / Wang, Xiangli

    Analytical Chemistry. 2023 Jan. 13, v. 95, no. 4 p.2253-2259

    2023  

    Abstract: Double spike (DS) method has been extensively used in determining stable isotope ratios of many elements. However, challenges remain in obtaining high-precision isotope data for ultra-trace elements owing to the limitations of instrumental signal-to- ... ...

    Abstract Double spike (DS) method has been extensively used in determining stable isotope ratios of many elements. However, challenges remain in obtaining high-precision isotope data for ultra-trace elements owing to the limitations of instrumental signal-to-noise ratios and the systematics of precision of DS-based measurements. Here, the DS-standard addition (SA) (DSSA) technique is proposed to improve measurements of isotope compositions of ultra-trace elements in natural samples. According to the U-shaped relationship between DS measurement uncertainty and the spike/sample ratio, theoretical equations and an error propagation model (EPM) were constructed comprehensively. In our method, a spiked secondary standard solution with a high, precisely known spike/sample ratio is mixed with samples such that the mixtures have spike/sample ratios within the optimal range. The abundances of the samples relative to the added standards (sample fraction; f ₛₚₗ) and the samples’ isotope ratios can then be obtained exactly using a standard DS data reduction routine and the isotope binary mixing model. The accuracy and precision of the DSSA approach were verified by measurements of cadmium and molybdenum isotopes at as low as 5 ng levels. Compared with traditional DS measurements, the sample size for isotope analysis is reduced to 1/6–1/5 of the original with no loss of measurement precision. The optimal mixing range f ₛₚₗ = 0.15–0.5 is recommended. The DSSA method can be extended to isotope measurement of more than 33 elements where the DS method is applicable, especially for the ultra-trace elements such as platinum group and rare earth element isotopes.
    Keywords analytical chemistry ; cadmium ; models ; molybdenum ; platinum ; rare earth elements ; sample size ; stable isotopes ; uncertainty
    Language English
    Dates of publication 2023-0113
    Size p. 2253-2259.
    Publishing place American Chemical Society
    Document type Article ; Online
    ZDB-ID 1508-8
    ISSN 1520-6882 ; 0003-2700
    ISSN (online) 1520-6882
    ISSN 0003-2700
    DOI 10.1021/acs.analchem.2c03802
    Database NAL-Catalogue (AGRICOLA)

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  2. Article ; Online: Double Spike-Standard Addition Technique and Its Application in Measuring Isotopes.

    Lu, Zhuo / Zhu, Jian-Ming / Tan, Decan / Johnson, Thomas M / Wang, Xiangli

    Analytical chemistry

    2023  Volume 95, Issue 4, Page(s) 2253–2259

    Abstract: Double spike (DS) method has been extensively used in determining stable isotope ratios of many elements. However, challenges remain in obtaining high-precision isotope data for ultra-trace elements owing to the limitations of instrumental signal-to- ... ...

    Abstract Double spike (DS) method has been extensively used in determining stable isotope ratios of many elements. However, challenges remain in obtaining high-precision isotope data for ultra-trace elements owing to the limitations of instrumental signal-to-noise ratios and the systematics of precision of DS-based measurements. Here, the DS-standard addition (SA) (DSSA) technique is proposed to improve measurements of isotope compositions of ultra-trace elements in natural samples. According to the U-shaped relationship between DS measurement uncertainty and the spike/sample ratio, theoretical equations and an error propagation model (EPM) were constructed comprehensively. In our method, a spiked secondary standard solution with a high, precisely known spike/sample ratio is mixed with samples such that the mixtures have spike/sample ratios within the optimal range. The abundances of the samples relative to the added standards (sample fraction;
    Language English
    Publishing date 2023-01-13
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1508-8
    ISSN 1520-6882 ; 0003-2700
    ISSN (online) 1520-6882
    ISSN 0003-2700
    DOI 10.1021/acs.analchem.2c03802
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Antimony isotope fractionation and the key controls in the soil profiles of an antimony smelting area.

    Liao, Jie / Tan, Decan / Qin, Haibo / Han, Qiao / Liu, Enguang / Chen, Jingan / Ning, Zengping / Li, Shehong

    Journal of hazardous materials

    2023  Volume 454, Page(s) 131553

    Abstract: The controlling factors of antimony migration and transformation in soil profiles are still unclear. Antimony isotopes might be a useful tool to trace it. In this paper, antimony isotopic compositions of plant and smelter-derived samples, and two soil ... ...

    Abstract The controlling factors of antimony migration and transformation in soil profiles are still unclear. Antimony isotopes might be a useful tool to trace it. In this paper, antimony isotopic compositions of plant and smelter-derived samples, and two soil profiles were measured for the first time. The δ
    Language English
    Publishing date 2023-05-02
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 1491302-1
    ISSN 1873-3336 ; 0304-3894
    ISSN (online) 1873-3336
    ISSN 0304-3894
    DOI 10.1016/j.jhazmat.2023.131553
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Microscale Investigation into Selenium Distribution and Speciation in Se-Rich Soils from Enshi, China.

    Qin, Hai-Bo / Zhu, Jian-Ming / Tan, Decan / Xu, Wen-Po / Liang, Dong-Xu / Takahashi, Yoshio

    Bulletin of environmental contamination and toxicology

    2021  Volume 106, Issue 1, Page(s) 40–43

    Abstract: In this study, we investigated the distribution and chemical speciation of Se in Se-rich soil by using micro-focused X-ray absorption near-edge structure (μ-XANES) spectroscopy coupling with X-ray fluorescence (μ-XRF) mapping. The microscale distribution ...

    Abstract In this study, we investigated the distribution and chemical speciation of Se in Se-rich soil by using micro-focused X-ray absorption near-edge structure (μ-XANES) spectroscopy coupling with X-ray fluorescence (μ-XRF) mapping. The microscale distribution showed that Se is heterogeneously distributed in the soil from seleniferous areas in Enshi, China. Se K-edge μ-XANES analysis suggested that Se is mainly present as Se(IV), organic Se(-II) or Se(0) species in Se-rich agricultural soil. The findings from this study would help improve the understanding of the fate, mobility, bioavailability, and biogeochemical cycling of Se in the seleniferous soil environment.
    MeSH term(s) China ; Selenium/analysis ; Soil ; Soil Pollutants/analysis ; X-Ray Absorption Spectroscopy
    Chemical Substances Soil ; Soil Pollutants ; Selenium (H6241UJ22B)
    Language English
    Publishing date 2021-01-16
    Publishing country United States
    Document type Journal Article
    ZDB-ID 6895-0
    ISSN 1432-0800 ; 0007-4861
    ISSN (online) 1432-0800
    ISSN 0007-4861
    DOI 10.1007/s00128-020-03090-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Microscale Investigation into Selenium Distribution and Speciation in Se‐Rich Soils from Enshi, China

    Qin, Hai-Bo / Zhu, Jian-Ming / Tan, Decan / Xu, Wen-Po / Liang, Dong-Xu / Takahashi, Yoshio

    Bulletin of environmental contamination and toxicology. 2021 Jan., v. 106, no. 1

    2021  

    Abstract: In this study, we investigated the distribution and chemical speciation of Se in Se-rich soil by using micro-focused X-ray absorption near-edge structure (μ-XANES) spectroscopy coupling with X-ray fluorescence (μ-XRF) mapping. The microscale distribution ...

    Abstract In this study, we investigated the distribution and chemical speciation of Se in Se-rich soil by using micro-focused X-ray absorption near-edge structure (μ-XANES) spectroscopy coupling with X-ray fluorescence (μ-XRF) mapping. The microscale distribution showed that Se is heterogeneously distributed in the soil from seleniferous areas in Enshi, China. Se K-edge μ-XANES analysis suggested that Se is mainly present as Se(IV), organic Se(-II) or Se(0) species in Se-rich agricultural soil. The findings from this study would help improve the understanding of the fate, mobility, bioavailability, and biogeochemical cycling of Se in the seleniferous soil environment.
    Keywords X-radiation ; X-ray absorption spectroscopy ; agricultural soils ; bioavailability ; chemical speciation ; edaphic factors ; fluorescence ; pollution ; selenium ; toxicology ; China
    Language English
    Dates of publication 2021-01
    Size p. 40-43.
    Publishing place Springer US
    Document type Article
    Note NAL-AP-2-clean
    ZDB-ID 6895-0
    ISSN 1432-0800 ; 0007-4861
    ISSN (online) 1432-0800
    ISSN 0007-4861
    DOI 10.1007/s00128-020-03090-7
    Database NAL-Catalogue (AGRICOLA)

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  6. Article ; Online: Adsorption of cadmium on clay-organic associations in different pH solutions: The effect of amphoteric organic matter.

    Xu, Wenpo / Liu, Chengshuai / Zhu, Jian-Ming / Bu, Hongling / Tong, Hui / Chen, Manjia / Tan, Decan / Gao, Ting / Liu, Yizhang

    Ecotoxicology and environmental safety

    2022  Volume 236, Page(s) 113509

    Abstract: Clay minerals are important soil components and usually coexist with organic matter, forming mineral-organic associations (MOAs), which control the speciation, mobility, and bioavailability of heavy metals. However, the adsorption mechanism of cadmium ( ... ...

    Abstract Clay minerals are important soil components and usually coexist with organic matter, forming mineral-organic associations (MOAs), which control the speciation, mobility, and bioavailability of heavy metals. However, the adsorption mechanism of cadmium (Cd) by MOAs is still unclear, especially for the associations of amphotericorganic matter and clay minerals. In this study, 12-aminododecanoic acid (ALA) and montmorillonite (Mt) were chosen to prepare MOAs via intercalation (Mt-ALA composite) and physical mixing (Mt-ALA mixture). Batch experiments were conducted to investigate the adsorption mechanism of Cd(II) by MOAs under different pH values and initial Cd(II) concentrations. The results showed that the Cd(II) adsorption capacities followed as Mt > Mt-ALA mixture > Mt-ALA composite under acidic conditions, Mt-ALA mixture > Mt > Mt-ALA composite under neutral conditions, and Mt-ALA mixture > Mt-ALA composite > Mt under alkaline conditions, suggesting the adsorption behaviors of Cd(II) by MOAs were primarily constrained by the speciation of ALA and solution pH. Under acidic conditions, cationic HALA
    MeSH term(s) Adsorption ; Bentonite/chemistry ; Cadmium ; Clay ; Hydrogen-Ion Concentration ; Minerals ; Soil/chemistry ; Soil Pollutants/chemistry
    Chemical Substances Minerals ; Soil ; Soil Pollutants ; Cadmium (00BH33GNGH) ; Bentonite (1302-78-9) ; Clay (T1FAD4SS2M)
    Language English
    Publishing date 2022-04-11
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 436536-7
    ISSN 1090-2414 ; 0147-6513
    ISSN (online) 1090-2414
    ISSN 0147-6513
    DOI 10.1016/j.ecoenv.2022.113509
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Active methanogenesis during the melting of Marinoan snowball Earth.

    Zhao, Zhouqiao / Shen, Bing / Zhu, Jian-Ming / Lang, Xianguo / Wu, Guangliang / Tan, Decan / Pei, Haoxiang / Huang, Tianzheng / Ning, Meng / Ma, Haoran

    Nature communications

    2021  Volume 12, Issue 1, Page(s) 955

    Abstract: Geological evidence indicates that the deglaciation of Marinoan snowball Earth ice age (~635 Myr ago) was associated with intense continental weathering, recovery of primary productivity, transient marine euxinia, and potentially extensive ... ...

    Abstract Geological evidence indicates that the deglaciation of Marinoan snowball Earth ice age (~635 Myr ago) was associated with intense continental weathering, recovery of primary productivity, transient marine euxinia, and potentially extensive CH
    Language English
    Publishing date 2021-02-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-021-21114-6
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Selenium speciation in seleniferous agricultural soils under different cropping systems using sequential extraction and X-ray absorption spectroscopy.

    Qin, Hai-Bo / Zhu, Jian-Ming / Lin, Zhi-Qing / Xu, Wen-Po / Tan, De-Can / Zheng, Li-Rong / Takahashi, Yoshio

    Environmental pollution (Barking, Essex : 1987)

    2017  Volume 225, Page(s) 361–369

    Abstract: Selenium (Se) speciation in soil is critically important for understanding the solubility, mobility, bioavailability, and toxicity of Se in the environment. In this study, Se fractionation and chemical speciation in agricultural soils from seleniferous ... ...

    Abstract Selenium (Se) speciation in soil is critically important for understanding the solubility, mobility, bioavailability, and toxicity of Se in the environment. In this study, Se fractionation and chemical speciation in agricultural soils from seleniferous areas were investigated using the elaborate sequential extraction and X-ray absorption near-edge structure (XANES) spectroscopy. The speciation results quantified by XANES technique generally agreed with those obtained by sequential extraction, and the combination of both approaches can reliably characterize Se speciation in soils. Results showed that dominant organic Se (56-81% of the total Se) and lesser Se(IV) (19-44%) were observed in seleniferous agricultural soils. A significant decrease in the proportion of organic Se to the total Se was found in different types of soil, i.e., paddy soil (81%) > uncultivated soil (69-73%) > upland soil (56-63%), while that of Se(IV) presented an inverse tendency. This suggests that Se speciation in agricultural soils can be significantly influenced by different cropping systems. Organic Se in seleniferous agricultural soils was probably derived from plant litter, which provides a significant insight for phytoremediation in Se-laden ecosystems and biofortification in Se-deficient areas. Furthermore, elevated organic Se in soils could result in higher Se accumulation in crops and further potential chronic Se toxicity to local residents in seleniferous areas.
    MeSH term(s) Agriculture/methods ; Biodegradation, Environmental ; Biological Availability ; Chemical Fractionation ; Crops, Agricultural ; Selenium/analysis ; Selenium/chemistry ; Soil/chemistry ; Soil Pollutants/analysis ; Soil Pollutants/chemistry ; X-Ray Absorption Spectroscopy ; X-Rays
    Chemical Substances Soil ; Soil Pollutants ; Selenium (H6241UJ22B)
    Language English
    Publishing date 2017-06
    Publishing country England
    Document type Journal Article
    ZDB-ID 280652-6
    ISSN 1873-6424 ; 0013-9327 ; 0269-7491
    ISSN (online) 1873-6424
    ISSN 0013-9327 ; 0269-7491
    DOI 10.1016/j.envpol.2017.02.062
    Database MEDical Literature Analysis and Retrieval System OnLINE

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