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Determination of Cadmium in TSP, PM10 in urban areas by hydride generation atomic fluorescence spectrometry

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Journal of Environmental Science and Engineering 2007年第1期1卷 39-43,54页

作者： liANG Shu-xuan li ling zhou Wei-jing LV Tian-feng SUN Han-wen Key Laboratory of Analytical Science and Technology of Hebei Province College of Chemistry and Environmental Science Hebei University Baoding 071002 China

In this paper, two different diameter particles （TSP, PM10） were collected by TH-16A four-channels classification air sampler. The samples were treated by HNO3. Analysis of cadmium was carried out by hydride generation atomic fluorescence spectrometry （HG-AFS） method, and distribution proportions of elements in four phases were calculated. This method was based on the reaction of cadmium with 1.5% （m/v） KBH4 solution and 0.5% KOH（m/v） solution to form the hydride gas in medium of 2% （v/v） HCl. The detection limit for cadmium as low as 0.008μg/L was obtained. The lineally correlation coefficient was 0.99992. The relative standard deviation （n=5, C=1.00μg/L） was 3.26%. The proposed method was applied for the determination of cadmium in atmosphere aerosol samples and the recoveries in the range of 95-102.2% were obtained. This method was simple, rapid, less matrix interference and high sensitivity.

关键词： hydride generation atomic fluorescence spectrometry atmosphere aerosol Cadmium

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei li Xiaoxiao Xu xuan Wu Jiarui li Shiling Chen Danyang Chen Gaigai li zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao zhou Xiongbin Luo Hang li Shan Guo Zhuang Tong Xiaotao zhou Xu li Zhaohui Hou Shuquan liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

ON THE OCCURRENCE OF Sewardiodendron laxum FLORIN (TAXODIACEAE) IN THE MIDDLE JURASSIC FROM YIMA, HENAN

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Chinese Science Bulletin 1989年第23期34卷 1980-1982页

作者：姚宣丽周志炎章伯乐 Nanjing Institute of Geology and Palaeontology Academia Smica Nanjing 210008 PRC Fourth Team of Jiangsu Bureau of Coal Geology

Since Florin proposed the generic name Sewardiodendron for some Jurassic confierous shoots from Yorkshire in 1958, no reproductive organs of this genus have ever been found. Harris, therefore, was disposed to reject t... 详细信息

关键词： Middle Jurassic Taxodlaceae Sewardiodendron male and female cones

Fine-tuning the spatial allocation of phytohormones for smart canopy, smart breeding, and smart agriculture

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Science China life Sciences 2025年第1期 309-310页

作者： Tao zhou lin li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University HuBei HongShan Laboratory

The dual challenges of global climate change and population growth have increased demand for higher crop yields per unit area. The innovative technology of smart agriculture aims to synergize breeding, cultivation, and production through the application of biological and informatics technologies. Historically, the “Green Revolution” introduced semidwarf varieties of certain key crops by utilizing mutations affecting gibberellin pathways, which significantly increased planting densities and yields.

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Wafer-Scale Vertical 1D GaN Nanorods/2D MoS₂/PEDOT:PSS for Piezophototronic Effect-Enhanced Self-Powered Flexible Photodetectors

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Tang, Xin Jiang, Hongsheng lin, Zhengliang Wang, xuan Wang, Wenliang li, Guoqiang South China Univ Technol State Key Lab Luminescent Mat & Devices Guangzhou 510640 Peoples R China South China Univ Technol Sch Mat Sci & Engn Dept Elect Mat Guangzhou 510640 Peoples R China

Vertical 1D GaN nanorod arrays/2D MoS2/PEDOT:PSS heterostructures in wafer scale have been fabricated for flexible photodetection ***-powered flexible photodetector at compressive strain reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1 and response times of 40/45 mu s, which are superior to the state-of-the-art flexible *** work not only provides a valuable strategy for the design and construction of tunable van der Waals heterostructures, but also opens a new opportunity for flexible sensors. van der Waals (vdW) heterostructures constructed by low-dimensional (0D, 1D, and 2D) materials are emerging as one of the most appealing systems in next-generation flexible photodetection. Currently, hand-stacked vdW-type photodetectors are not compatible with large-area-array fabrication and show unimpressive performance in self-powered mode. Herein, vertical 1D GaN nanorods arrays (NRAs)/2D MoS2/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly. The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W-1 and a high detectivity of 1.2 x 1011 Jones, as well as a fast response speed of 54/71 mu s, thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction. Notably, the strain-tunable photodetection performances of device have been demonstrated. Impressively, the device at - 0.78% strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1, a detectivity of 2.6 x 1011 Jones, and response times of 40/45 mu s, which are superior to the state-of-the-art self-powered flexible photodetectors. This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection, which performs well in flexible sensors.

关键词： Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors

TC4合金表面Zr增效硅化物涂层的组织结构及韧性

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材料热处理学报 2017年第7期38卷 132-137页

作者：李轩周立玉谢文玲李寅凤王凯强四川理工学院机械工程学院四川自贡643000 材料腐蚀与防护四川省重点实验室四川自贡643000

采用扩散共渗的方法在TC4合金表面制备了Zr增效的硅化物涂层,研究了涂层的组织形成机制和韧性。结果表明,所制备的涂层具有多层结构,由外向内分别由(Ti,X)Si_2(X代表Zr、Al和V)外层、TiSi中间层和Ti_5Si_4+Ti_5Si_3内层组成。涂层的形... 详细信息

采用扩散共渗的方法在TC4合金表面制备了Zr增效的硅化物涂层,研究了涂层的组织形成机制和韧性。结果表明,所制备的涂层具有多层结构,由外向内分别由(Ti,X)Si_2(X代表Zr、Al和V)外层、TiSi中间层和Ti_5Si_4+Ti_5Si_3内层组成。涂层的形成主要受Si向基体合金内的扩散控制,Zr在渗包内的卤化物气相分压虽然较Si的高,但扩散速率较慢,在涂层内的含量较低。与TC4合金表面单一硅化物涂层相比,Zr增效硅化物涂层具有更优良的韧性。

关键词： TC4合金 Zr增效硅化物涂层组织结构韧性

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi li Yang Wei Kang zhou Xin Huang Xing zhou Jie Xu Taoyi Kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （lic *** three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

Recent development in electrode design for wide-temperature supercapacitors

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Science China Chemistry 2025年第1期 96-117页

作者： Jianhong liu Qiang zhou Yuxiao lin Xinsheng Zhao Guangmin zhou Xiaoxiao li School of Physics and Electronic Engineering Jiangsu Normal University Tsinghua-Berkeley Shenzhen Institute & Tsinghua Shenzhen International Graduate School Tsinghua University

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(SCs). The active electrode is one of the most important parts of SC, which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the SC electrodes aimed for room-temperature application, the SC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of SC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature SC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature SCs are also proposed.

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