Thallium (Tl) is a dispersed trace metal showing remarkable toxicity. Various anthropogenic activities may generate Tl contamination in river sediments, posing tremendous risks to aquatic life and human health. This p...
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Thallium (Tl) is a dispersed trace metal showing remarkable toxicity. Various anthropogenic activities may generate Tl contamination in river sediments, posing tremendous risks to aquatic life and human health. This paper aimed to provide insight into the vertical distribution, risk assessment and source tracing of Tl and other potentially toxic elements (PTEs) (lead, cadmium, zinc and copper) in three representative sediment cores from a riverine catchment impacted by multiple anthropogenic activities (such as steel-making and Pb-Zn smelting). The results showed high accumulations of Tl combined with associated PTEs in the depth profiles. Calculations according to three risk assessment methods by enrichment factor (EF), geoaccumulation index (I-geo) and the potential ecological risk index (PERI) all indicated a significant contamination by Tl in all the sediments. Furthermore, lead isotopes were analyzed to fingerprint the contamination sources and to calculate their quantitative contributions to the sediments using the IsoSource software. The results indicated that a steel-making plant was the most important contamination source (similar to 56%), followed by a Pb-Zn smelter (similar to 20%). The natural parental bedrock was found to contribute similar to 24%. The findings highlight the importance of including multiple anthropogenic sources for quantitative fingerprinting of Tl and related metals by the lead isotopic approach in complicated environmental systems. (C) 2020 Elsevier Ltd. All rights reserved.
Research about constructing multi-dimensional carbon nanomaterials is of great significance in electrocatalytic and sensing fields in order to integrate structural merits of each individual unit. Also, nano-materials ...
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Research about constructing multi-dimensional carbon nanomaterials is of great significance in electrocatalytic and sensing fields in order to integrate structural merits of each individual unit. Also, nano-materials with enzyme-like activities are prospective candidates for artificial enzyme design and electrochemical application. Herein, we fabricate Co, N co-doped hierarchical hybrid (Co@NCNTs/NC) nanozyme, which integrates of both N-doped carbon nanotubes (NCNTs) and N-doped carbon sheets (NC). The three-dimensional (3D) porous carbon composite is prepared by thermal treatment of metal-organic framework (MOF) which was synthesized by growing of ZIF-67 on ZIF-L at room temperature. The obtained nanomaterial not only possesses an improved oxidase-like activity that can catalyze 3,3',5,5'-tetramethylbenzidine (TMB) in the absence of hydrogen peroxide (H2O2), but also constructs a signal amplification platform towards dopamine (DA) due to the synergistic catalysis of Co species and N-doped porous carbon architecture. The electrocatalytic performance for DA detection shows a broad linear range from 30 nM to 710 mu M and a detection limit of 9 nM. The Co@NCNTs/NC/GCE is employed to practically detect DA in human serum and artificial cerebrospinal fluid (aCSF) samples with satisfactory results. The present work exhibits a great promising in colorimetric and electrochemical sensing fields and presents a new sight for the fabrication of MOF-derived nanozyme. (C) 2021 Elsevier Ltd. All rights reserved.
目的研究发状分裂相关增强子1(hairy and enhancer of split 1,Hes1)蛋白在经典型骨肉瘤中的表达及其与临床特征和预后的关系。方法收集本院2007年4月至2016年10月初诊初治并明确诊断的经典型骨肉瘤患者标本56例,运用免疫组织化学检测H...
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目的研究发状分裂相关增强子1(hairy and enhancer of split 1,Hes1)蛋白在经典型骨肉瘤中的表达及其与临床特征和预后的关系。方法收集本院2007年4月至2016年10月初诊初治并明确诊断的经典型骨肉瘤患者标本56例,运用免疫组织化学检测Hes1蛋白的表达,分析其表达与临床病理特征及术后转归的关系。对患者总生存和无进展生存情况进行随访,随访至术后5年,采用Kaplan-Meier法和log-rank检验进行生存分析。结果56例患者中,Hes1高表达22例(39.3%),低表达34例(60.7%)。与Hes1低表达患者比较,Hes1高表达患者的肿瘤直径更大(P=0.018),术后复发率及转移率均更高(均P<0.05)。Hes1低表达和高表达患者5年内平均总生存期为52.7个月和38.4个月(P=0.001),5年内平均无进展生存期为48.3个月和22.6个月(P<0.01)。Cox多因素回归分析提示,Hes1表达水平是患者总生存和无进展生存的预后独立风险因素(均P<0.01)。结论经典型骨肉瘤中Hes1蛋白的高表达与术后复发、转移及生存时间缩短相关。
In this study, CuFe2O4 nanocomposite loaded on natural sepiolite (CuFe2O4/SEP) was prepared by the citrate sol-gel method. CuFe2O4/SEP was characterized by X-ray diffraction, Brunauer-Emmett-Teller adsorption analysis...
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In this study, CuFe2O4 nanocomposite loaded on natural sepiolite (CuFe2O4/SEP) was prepared by the citrate sol-gel method. CuFe2O4/SEP was characterized by X-ray diffraction, Brunauer-Emmett-Teller adsorption analysis, scanning electron microscopy, and energy dispersive spectroscopy. The CuFe2O4/SEP composite was stable and showed an excellent catalytic activity for ozonation. The efficiency of quinoline mineralization in the catalytic ozonation with CuFe2O4/SEP was 90.3%, and this value was 5.4 times higher than that of the uncatalyzed ozonation (16.8%). The quinoline mineralization followed a pseudo first-order kinetics with all the catalysts. The rate constant for the mineralization of quinoline by ozonation in the presence of CuFe2O4/SEP was 0.0885 min(-1), which was 16.7 times higher than that in ozone alone (0.0053 min(-1) ). Radical scavenging tests revealed that hydroxyl radical (center dot OH) and superoxide radical (center dot O-2(-)) were the reactive oxygen species (ROS) in the quinoline degradation. In the presence of CuFe2O4/SEP, ozone and hydrogen peroxide were rapidly converted into the ROS. Although neutral and alkaline pH were more beneficial for the quinoline mineralization, CuFe2O4/SEP exhibited significant catalytic activity even under acidic conditions. Meanwhile, five-cycle successive tests suggested that CuFe2O4/SEP was recyclable and hence, stable. Furthermore, the feasibility of the catalytic ozonation for the treatment of biologically treated coking wastewater was evaluated. The catalytic ozonation resulted in 57.81% total organic carbon removal efficiency at 60 min, which was 2.9 times higher than that in the uncatalyzed ozonation (19.99%). (C) 2019 Elsevier Ltd. All rights reserved.
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