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Ultra-sensitive detection of uranyl ions with a specially designed high-efficiency SERS-based microfluidic device

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Science China Chemistry 2019年第8期62卷 1064-1071页

作者： Xuan He shaofei wang Yu Liu Xiaolin wang College of Chemistry Sichuan UniversityChengdu 610064China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Institute of Materials China Academy of Engineering PhysicsMianyang 621907China China Academy of Engineering Physics Mianyang 621900China

The uranyl ion(UO22+) poses high risks to human health and the environment, hence its detection and monitoring is of utmost significance. However, the development of an ultra-sensitive, high-efficiency and convenient approach for on-site detection of UO22+ remains a challenge. Herein, a reliable and reusable surface-enhanced Raman spectroscopy(SERS)-based microfluidic biosensor was developed for rapid detection of UO22+ in real samples. The detection protocol involved the reaction of 5′-Rhodamine B(RhB)-labeled double-stranded DNA for UO22+-specific DNAzyme-cleavage reaction in a U-shaped microchannel. Then, the reaction products were delivered into three parallel samples for high-throughput tests by SERS biochips,where 3 D ZnO-Ag mesoporous nanosheet arrays(MNSs) were modified with a single-stranded DNA(ssDNA). The ssDNAwas sequence-complementary with the 5′-RhB-labeled cleaved-stranded DNA(csDNA) from the reaction products. By the hybridization of ssDNA and csDNA, the signal probe RhB was fixed close to the surface of the ZnO-Ag MNSs to enhance the Raman signal. The limit of detection for UO22+ with the microfluidic-SERS biosensor was 3.71×10-15 M. An over 20,000-fold selectivity towards UO22+ response was also achieved in the presence of 15 other metal ions. The high-throughput microfluidicSERS biosensor operated well for practical UO22+ detection, with excellent recoveries in contaminated river and tap water from95.2% to 106.3%(relative standard deviation(RSD)<6.0%, n=6). Although the SERS-based microfluidic biosensor developed in this study was deployed for the detection of UO22+, the reusable and high-efficiency system may be expanded to the detection of other analytes on-site.

关键词： uranyl ion DNAzyme SERS microfluidic device high-throughput reusable

Water quality,natural chemical weathering and ecological risk assessment of the contaminated area of vanadium ore in Yinhua River,China:Evidence from major ions and trace elements

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Acta Geochimica 2022年第1期41卷 84-99页

作者： Delu Li Yong Xu Xiaotuan Zhang Zhidong Yang shaofei wang Qianyang He Zhe Jia Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi’an University of Science and TechnologyXi’an 710054China Geological Research Institute for Coal Green Mining Xi’an University of Science and TechnologyXi’an 710054China College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China Shaanxi Institute of Geological Survey Xi’an 710054China College of Geomatics Xi’an University of Science and TechnologyXi’an 710054China

There are abundant vanadium ores in the Cambrian strata in southern Shaanxi,*** years of mining activities and surface leaching have polluted the surface water to a certain extent,but the researches on the water quality characteristics and pollution degree are relatively *** contribution was organized to investigate the surface water quality by general parameters,including TDS,Eh,pH,DO,TOC,COD,and EC,in the vanadium ore belt(Yinhua River basin).Major ions were determined to detect the water type and natural chemical weathering,while trace elements were used to illustrate their geochemical characteristics and ecological risk assessment of heavy *** study found that the surface water was weakly alkaline and mainly dominated from normal to pool *** particle size with1000–10,000 nm of suspended particles was the main carrier of organic *** concentration of HCO_(3)^(-)and SO_(4)^(2-)in the anions and Ca^(2+)and Mg^(2+)ions in the cations were relatively high,and the water type was Ca-Mg-HCO_(3)-SO_(4) *** weathering had a great influence on surface water,and the weathering products were mainly silicate and *** with the Type river,the contents of V elements showed an obvious positive anomaly,which may be affected by mining activities of vanadium ore and the annual leaching of the tailings *** and Cd in the surface water was polluted *** integrated pollution index suggested that the surface water pollution was serious,and the main stream was more serious with the increasing tailings ponds.

关键词： Vanadium ore belt Surface water Water contamination Major ions Trace elements

The contribution of photoinduced charge-transfer enhancement to the SERS of uranyl(Ⅵ) in a uranyl-Ag_2O complex

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Science Bulletin 2019年第5期64卷 315-320页

作者： shaofei wang Shanli Yang Haoxi Wu Jiaolai Jiang Lang Shao Yiming Ren Yingru Li Chuanhui Liang Mingfu Chu Xiaolin wang Institute of Materials China Academy of Engineering Physics China Academy of Engineering Physics

Charge-transfer(CT) is an important enhancement mechanism in the field of surface-enhanced Raman scattering(SERS) that typically increases the Raman intensity of molecules by as much as 10–100 ***, a low-cost Ag_2O aggregates substrate was prepared via a facile chemical precipitation method,and the calculated CT-based enhancement factor of the uranyl ions adsorbed on it reached as high as 10~5, a metal-comparable value. The efficient photoinduced CT process from the valence band of Ag_2O to the LUMO of uranyl ions under appropriate excitation sources resulted in the repulsion of the axial oxygen atoms of the O=U=O bond, which enhanced its polarizability, creating a more intense Raman mode. To the best of our knowledge, this study firstly reports such a strong photoinduced CT enhancement of uranyl ions, with concentrations of 10^(-8) mol L^(-1) or lower being detected using this Ag_2O substrate. Most importantly, this research has shown that the photoinduced CT enhancement also contributes to the SERS of uranyl ions on pure Ag substrates which have often been ascribed to the electromagnetic enhancement in previous studies. In addition, Ag_2O can be used to selectively detect uranyl ions without interference from many other molecules or ions because of the energy matching rule of the photoinduced CT process, which was readily available for uranyl detection in the environmental aqueous solution.

关键词： Photoinduced charge-transfer Uranyl SERS Ag2O aggregates Trace analysis

Tailoring interphase structure to enable high-rate, durable sodium-ion battery cathode

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Journal of Energy Chemistry 2022年第5期31卷 564-571页

作者： Na Li shaofei wang Enyue Zhao Wen Yin Zhigang Zhang Kang Wu Juping Xu Yoshihiro Kuroiwa Zhongbo Hu Fangwei wang Jinkui Zhao Xiaoling Xiao College of Materials Science and Opto-electronic Technology Center of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803GuangdongChina Songshan Lake Materials Laboratory Dongguan 523808GuangdongChina Department of Physical Science Hiroshima UniversityHigashihiroshimaHiroshima 739-8526Japan Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Na-based layered transition metal oxides with O_(3)-type structure have been considered to be promising cathodes for Na-ion batteries. However, the intrinsically limited Na-ion conductivity induced by the Otype Na-coordinate environment compromises their rate and cycle capability, hindering their practical application. Here, we report an interphase-structure tailoring strategy that improves the electrochemical properties of O_(3)-type layered cathodes achieved through surface coating and doping ***, a Zr-doped interphase structure is designed in the model compound NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2) using the ionic conductor Na_(3)Zr_(2)Si_(2)PO_(12) as the surface coating material and Zr-dopant provider. We discover that the modified NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2)cathode shows a stable Na-storage structure as well as an enhanced rate/cycle capability. Combined with theoretical calculations, it is suggested that the superior electrochemical performances originate from the Zr-doped interphase structure, which has an enlarged Na layer spacing that forms favorable Na-ion diffusion channels. This work highlights a general material interface optimization method which opens a new perspective for fabricating high-performance electrodes for Na-ion batteries and beyond.

关键词： Na-ion battery NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2)cathode Interphase structure Zr doping Surface interface modification

Constraints of palaeoenvironment on organic matter of Benxi Formation shale and discussion on enrichment mechanism under different facies

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Frontiers of Earth Science 2024年第1期18卷 148-171页

作者： Qianyang HE Delu LI Qiang SUN Jianwen GAO Haibin LI Xinhu LI Xiaochen ZHAO shaofei wang Gaozhe JI College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi’an University of Science and TechnologyXi’an 710054China Geological Research Institute for Coal Green Mining Xi’an University of Science and TechnologyXi’an 710054China Research Institute of Exploration and Development PetroChina Changqing Oilfield CompanyXi’an 710018China School of Civil Engineering and Architecture Shaanxi University of TechnologyHanzhong 723001China

As a hydrocarbon-rich sedimentary basin in China,the Ordos Basin has enormous potential for shale gas *** shale of the Upper Carboniferous Benxi Formation is rich in organic matter,however,its palaeoenvironment and organic matter enrichment mode are yet to be *** this study,the geochemical characteristics of the shale of the Benxi Formation in the east-central part of the Ordos Basin were analyzed to investigate its *** the same time,the organic matter enrichment modes in different sedimentary facies were compared and *** results indicate that:1)the shale of the Benxi Formation was mainly deposited on the continental margin and strong terrestrial clastic input;2)the deposition period of the Benxi Formation shale had a hot and humid climate with high palaeoproductivity and local volcanic hydrothermal fluid,and a high sedimentation rate with the strong stagnant *** bottom water was in dysoxic conditions and a semi-saline deposition environment;3)multiple factors,such as palaeoproductivity,volcanic hydrothermal,redox conditions,and palaeosalinity interact to influence the enrichment of shale organic matter in Benxi Formation;4)the organic matter enrichment modes of continental,marine-continental transitional,and marine shales can be classified into three types:“production mode”,“hybrid mode of preservation and production”,and“preservation mode”,*** study provides a reference for the organic matter enrichment mode,shale gas formation conditions,and core area evaluation in these marine-continental transitional shales,and also offers new guidance for exploration ideas for shale gas in different sedimentary facies.

关键词： Benxi Formation shale palaeoenvironment organic matter enrichment facies

Electrospinning in membrane contactor:manufacturing Elec-PVDF/SiO2 superhydrophobic surface for efficient flue gas desulphurization applications

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Green Chemical Engineering 2021年第1期2卷 111-121页

作者： Qingping Xin Kaiqiang Xie Qingqing Liang Xu Li Yinan Zeng Yuhang Zhao Lei Zhang shaofei wang Hong Li Yuzhong Zhang State Key Laboratory of Separation Membranes and Membrane Processes School of Materials Science and EngineeringTiangong UniversityTianjin300387China Department of Chemical Engineering Massachusetts Institute of TechnologyCambridgeMA02139United States

In membrane contactors,maintaining a high SO_(2)absorption flux and an excellent wetting resistance are crucial for hazardous gas *** this study,we adopted an electrospinning strategy to fabricate highly robust superhydrophobic dual-layer Elec-PVDF/SiO_(2)composite membrane contactors used for flue gas *** composite membrane contactor consisted of a durable and ultrathin three-dimensional(3D)superhydrophobic surface and a porous supporting layer,where the formulation was optimized by regulating the PVDF concentration,solvent ratio and SiO_(2)particles content in electrospinning *** scanning electronic microscopy(SEM),EDS-mapping,water contact angle(WCA)and surface roughness of as-prepared Elec-PVDF/SiO_(2)composite membrane contactors were conducted to explore the physical and chemical *** SiO_(2)nanoparticles were uniformly loaded in ElecPVDF/SiO_(2)composite membrane contactor,and constructed micro-nano dual-coarse lotus-leaf-like morphology,which noticeably elevated surface roughness(Ra).The SiO_(2)nanoparticles also functioned as hydrophobic modifiers,which boosted the WAC up to 155.The SO_(2)absorption fluxes and SO_(2)removal efficiencies were *** particular,the membrane contactor doped with 20 wt%SiO_(2)nanoparticles significantly elevated the stability of desulfurization ***,the membrane mass transfer coefficient(Km)and corresponding membrane mass transfer resistance(H/Km)were explored.

关键词： Electrospinning Composite membrane contactor Superhydrophobic surface Flue gas desulfurization SO2 absorption flux

Precise Positioning of Pneumatic Artificial Muscle Systems

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Journal of Flow Control, Measurement & Visualization 2014年第4期2卷 138-153页

作者： shaofei wang Kaiji Sato Toshiharu Kagawa Interdisciplinary Graduate School of Science and Engineering Tokyo Institute of Technology Yokohama Japan

Pneumatic artificial muscles (PAMs) currently possess a high power-to-weight ratio, a high power-to-volume ratio, and a high degree of safety. They have therefore been applied to many power assist devices and positioning mechanisms such as bionic robots, welfare devices, and parallel manipulators. However, the significant nonlinear characteristics of PAM mechanisms limit their positioning accuracies. The accuracies are generally lower than 5 μm, which preclude the PAM from precision systems. Nevertheless, enhancing the positioning accuracy is desired to extend the application fields of PAMs. This study aims to clarify a practical controller design method to achieve the precise positioning of PAM systems. As the first step of this research, a linear motion mechanism with a pair of McKibben PAMs was constructed and a conventional dynamic model for this system is introduced. The dynamic model is used to explain the basic characteristics of the PAM mechanism and discuss the necessary characteristics for precise positioning. Then open-loop step and sinusoidal responses of the PAM mechanism were examined by experimental and simulated results. Next, for precise positioning, the practical controller design procedure is discussed and determined based on the measured open-loop responses. The proposed controller design procedure can be easily implemented into PAM mechanisms without an exact dynamic model. The positioning performance of such a system was experimentally evaluated. The experimental results show that although the positioning accuracy depends on the target position, the positioning error is lower than 1 μm even in the worst case and the positioning resolution can be set to 0.5 μm.

关键词： Precision Positioning McKibben Pneumatic Muscle Pneumatic Artificial Muscle Accuracy

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歧化及烷基转移催化剂的运行及工业再生

石油炼制与化工 2012年第7期43卷 22-25页

作者：王少飞中海石油炼化有限责任公司惠州炼油分公司广东惠州516086

介绍中海石油炼化有限责任公司惠州炼油分公司芳烃联合装置歧化及烷基转移单元高空速、低氢烃比条件下催化剂的运行及工业再生情况。采用C10+芳烃含量较高的原料,在较高空速、低氢烃比的条件下运行近2年,歧化催化剂积焦量达到39%以上,... 详细信息

介绍中海石油炼化有限责任公司惠州炼油分公司芳烃联合装置歧化及烷基转移单元高空速、低氢烃比条件下催化剂的运行及工业再生情况。采用C10+芳烃含量较高的原料,在较高空速、低氢烃比的条件下运行近2年,歧化催化剂积焦量达到39%以上,使催化剂活性下降。通过氢气汽提、低氧主烧焦和高氧清焦方法对催化剂进行再生,清除了约35.80t焦炭,再生后催化剂反应性能良好,表明催化剂具有良好的再生性能。

关键词：芳烃甲苯歧化催化剂再生

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效度概念的演进与课堂评价的效度

全球教育展望 2014年第6期43卷 87-94,102页

作者：王少非台州学院台州31700 华东师范大学课程与教学研究所

效度观经历了一个从单一概念到多种概念并存,再到一体化概念的演进过程。效度是大规模评价的一个重要的质量指标,并不完全适用于作为教学有机组成部分的课堂评价。课堂评价需要不同的效度观,课程效度和后果效度是最适合课堂评价的质量... 详细信息

效度观经历了一个从单一概念到多种概念并存,再到一体化概念的演进过程。效度是大规模评价的一个重要的质量指标,并不完全适用于作为教学有机组成部分的课堂评价。课堂评价需要不同的效度观,课程效度和后果效度是最适合课堂评价的质量标准。这需要课堂评价是基于课程标准的评价和促进学习的评价。

关键词：课堂评价效度课程效度后果效度