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Current status and prospects of research on 1,4-dioxane pollution and treatment technologies in the water environment

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Journal of Groundwater Science and Engineering 2023年第2期11卷 158-170页

作者： chun-xiao Wang Yong Qian Zhao-ji Zhang chen Yue chun-yan Guo xiang-xiang Cui Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Groundwater Contamination and Remediation China Geological Survey(CGS)&Hebei ProvinceShijiazhuang 050061China

1,4-dioxane pollution is characterized by its early identification, widespread sources and extensive distribution. The pollutant is highly mobile and persistent in the water environment and is classified as a B2(probable) human carcinogen. After reviewing recent researches on the pollution status,transport and transformation characteristics of 1,4-dioxane in the water environment, as well as the environmental pollution remediation and treatment technologies, and the status of environmental regulation,this paper addresses that the distribution of 1,4-dioxane in water bodies is significantly correlated with chlorinated hydrocarbon pollutants such as 1,1,1-trichloroethane(1,1,1-TCA) and trichloroethylene(TCE).It is noteworthy that 1,4-dioxane often occurs in symbiosis with 1,1,1-TCA and has a similarity contamination plume distribution to 1,1,1-TCA. The natural attenuation of 1,4-dioxane in groundwater environment is weak, but there is a certain degree of biological oxidation attenuation. Current methods for treating 1,4-dioxane pollution mainly include extraction-treatment technology, advanced oxidation treatment technology, modified biological treatment technology and phytoremediation technology, all of which have their limitations in practical application. Currently, there is no environmental regulation available for the 1,4-dioxane pollution worldwide, and no enforceable standard established for defining the health trigger levels of 1,4-dioxane in drinking water. Research on this contaminant in China is generally limited to the site or laboratory scale, and there are no studies on the environmental risk and quality standards for 1,4-dioxane in the water environment.

关键词： 1 4-dioxane Chlorinated hydrocarbon Environmental pollution Attenuation

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Molecular and morphological evidence for a new species of Isodon (Lamiaceae) from southern China

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Plant Diversity 2021年第1期43卷 54-62页

作者： Ya-Ping chen Cun-Zhong Huang Yue Zhao chun-Lei xiang CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Natural Resources Bureau of Guidong County Chenzhou 423000HunanChina University of Chinese Academy of Sciences Beijing 100049China

Isodon brevipedunculatus,a new species from southern China,is described and illustrated.The phylogenetic position of the new species within the genus was analyzed based on two nuclear ribosomal DNA regions and an ingroup sampling of about 80%of Asian species of Isodon.The results show that I.brevipedunculatus is recovered in a clade that consists of species mainly with glandular mericarps and that are distributed in the Sino-Japanese region.Combining molecular and geographical evidence,our study reveals that I.brevipedunculatus is most closely related to Isodon amethystoides and Isodon bifidocalyx,but differs from the former in lamina shape,number of flowers per cyme,and peduncle length,and from the latter in lamina indumentum,calyx morphology,and corolla length.

关键词： Himalaya-Hengduan Mountains region Isodoninae Mericarp Sino-Japanese region

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A preliminary phylogenetic study of Paraphlomis(Lamiaceae)based on molecular and morphological evidence

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Plant Diversity 2021年第3期43卷 206-215页

作者： Ya-Ping chen Ang Liu Xun-Lin Yu chun-Lei xiang CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina College of Forestry Central South University of Forestry and TechnologyChangsha410004HunanChina

Paraphlomis is a genus of Lamiaceae with about 30 species distributed mainly in subtropical China.In this study,we carried out the first molecular phylogenetic analyses to elucidate the relationships within the genus based on two nuclear and four plastid DNA regions.Our results,which recovered a species of Matsumurella within Paraphlomis,indicate that the genus is not monophyletic.The two sections and most of the series previously described within the genus are also shown to be polyphyletic.Combining with morphological evidence,our study indicates that nutlet morphology rather than calyx morphology is of phylogenetic value for the infrageneric classification of Paraphlomis.Moreover,P.jiangyongensis,a new species from southern China,is here described,and P.coronata,formerly treated as a variety of P.javanica,is here resurrected as a distinct species within the genus.

关键词： Ajugoides Infrageneric classification Matsumurella Nutlet Paraphlomideae

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Effect of vortex dynamics and instability characteristics on the induced drag of trailing vortices

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Chinese Journal of Aeronautics 2022年第9期35卷 160-173页

作者： Zepeng chenG Shiyan ZHANG Yang xiang chun SHAO Miao ZHANG Hong LIU Yingchun chen School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China Ltd.Shanghai 201210China

In this paper, trailing vortices generated by three wingtip configurations, namely the M6wing and the M6 wing with a blended or split winglet, are experimentally investigated using the Stereo Particle Image Velocimetry(SPIV) technology. Then, linear stability analysis is performed to investigate instability characteristics. Three corresponding trailing vortex patterns, including the isolated trailing vortex without wake(pattern v) and with wake(pattern v-w), co-rotating vortex pair(pattern v-v), are observed in experiments. The strength of trailing vortices, characterized by circulation, is reduced after installing winglets as expected, and the strength of pattern v-v can be further suppressed compared with pattern v-w. Moreover, instability characteristics, such as the eigenvalue spectrum and perturbation mode, are distinctive among these three vortex patterns.The distribution of eigenvalue spectrums indicates that pattern v and pattern v-w are temporally“marginally stable”, while pattern v-v is temporally “unstable.” The primary perturbation mode of pattern v and pattern v-w is the m =-1 helical mode, while |m|>1 for the case of pattern v-v.The effect of vortex dynamics and instability characteristics can be concluded in two aspects.Firstly, the value of induced drag is polluted by about 3% from vortex wandering since vortex wandering affects the tangential velocity and streamwise vorticity of trailing vortices. Secondly, the growth rate and penetration depth perturbation mode affect trailing vortex evolution and further affect induced drag. Specifically, the larger the growth rate and penetration depth are, the more turbulence injects inside the vortex core, thus leading to a quicker and more intense attenuation of trailing vortex, as well as a smaller induced drag. This finding can guide us to manipulate the induced drag in flow control.

关键词： Induced drag Linear stability analysis SPIV Trailing vortex Vortex flow Winglet

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On-demand inverse design of acoustic metamaterials using probabilistic generation network

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Science China(Physics,Mechanics & Astronomy) 2023年第2期66卷 87-94页

作者： Ze-Wei Wang An chen Zi-xiang Xu Jing Yang Bin Liang Jian-chun cheng Key Laboratory of Modern Acoustics MOEInstitute of Acoustics Department of PhysicsNanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing University.Nanjing 210093China

On-demand inverse design of acoustic metamaterials(AMs),which aims to retrieve the optimal structure according to given requirements,is still a challenging task owing to the non-unique relationship between physical structures and spectral responses.Here,we propose a probabilistic generation network(PGN) model to unveil this implicit relationship and implement this concept with an acoustic magic-cube absorber.By employing the auto-encoder-like configuration composed of a gate recurrent unit(GRU) and a deep neural network,our PGN model encodes the required spectral response into a latent space.The memory or feedback loop contained in the proposed GRU allows it to effectively recognize sequence characteristics of a spectrum.The method of modeling the inverse problem and retrieving multiple meta structures in a probabilistic generative manner skillfully solves the one-to-many mapping issue that is intractable in deterministic models.Moreover,to meet different sound absorption requirements,we tailored several representative spectra with low-frequency sound absorption characteristics,generating highprecision(MAE<0.06) predicted spectra with multiple meta structures.To further verify the effective prediction of the proposed PGN strategy,the experiment was carried out in a tailored broadband example,whose results coincide with both theoretical and numerical ones.Compared with other 5 networks,the PGN model exhibits higher accuracy and efficiency.Our work offers flexible and diversified solutions for multivalued inverse problems,opening up avenues to realize the on-demand de sign of AMs.

关键词： inverse probabilistic network

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Social functions of relaxed open-mouth display in golden snub-nosed monkeys(Rhinopithecus roxellana)

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Zoological Research 2019年第2期40卷 113-120页

作者： You-Ji Zhang Yi-Xin chen Hao-chun chen Yuan chen Hui Yao Wan-Ji Yang xiang-Dong Ruan Zuo-Fu xiang Institute of Evolutionary Ecology and Conservation Biology Central South University of Forestry & Technology College of Life Science and Technology Central South University of Forestry and Technology Shennongjia National Park National Forest Inventory and Design Institute

Relaxed open-mouth display serves important social functions in relation to submission, reconciliation affiliation and reassurance among non-human primate societies; however, quantitative evidence on this behavior remains insufficient among multi-level social groups. From July to November 2016, we examined four potential functions of the relaxed open-mouth display during pairwise, intra-unit social interactions among 18 free-ranging adult and sub-adult golden snub-nosed monkeys(Rhinopithecus roxellana) who belonged to three one-male, multi-female units(OMU) at Dalongtan, Shennongjia National Park China. Results showed that: compared with no relaxed open-mouth display,(1) the occurrence of displacement by a dominant individual approaching a subordinate was lower and the distance of the subordinate to the approaching dominant was shorter when the subordinate showed open-mouth display;(2) relaxed open-mouth display reduced the probability of continued attack for victims of aggression and allowed victims to achieve closer proximity to the aggressor during post-conflict periods;(3) relaxed open-mouth display by dominant individuals allowed them to achieve closer proximity to subordinates; and(4) the exchange of relaxed open-mouth display had a greater impact on the outcome of interactions than one individual alone giving this signal. These findings suggest that relaxed open-mouth display serves important functions regarding submission, reconciliation, affiliation and reassurance in coordinating social interactions within OMUs in golden snub-nosed monkeys.

关键词： Golden snub-nosed monkey Open- mouth Submission Reconciliation Affiliation Reassurance

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间充质干细胞治疗肝纤维化的现况和前景（英文）

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2016年第11期17卷 831-841页

作者： Yang GUO Bo chen Li-jun chen chun-feng ZHANG Charlie xiang State Key Laboratory for Diagnosis and Treatment of Infectious Diseases and Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University

许多慢性肝病发展到终末阶段形成肝纤维化进而转变成肝硬化,严重威胁人们的健康。目前临床治疗肝纤维化的有效方法是肝移植,但由于供体缺乏、免疫排斥和治疗费用昂贵等诸多缺陷,这种疗法并不是一种理想的治疗途径。近些年细胞治疗研究火... 详细信息

许多慢性肝病发展到终末阶段形成肝纤维化进而转变成肝硬化,严重威胁人们的健康。目前临床治疗肝纤维化的有效方法是肝移植,但由于供体缺乏、免疫排斥和治疗费用昂贵等诸多缺陷,这种疗法并不是一种理想的治疗途径。近些年细胞治疗研究火热,间充质干细胞作为一种来源广泛、可定向迁移和多向分化的治疗载体,在肝纤维化治疗上具有广阔的应用前景。本文对间充质干细胞治疗肝纤维化的现状进行归纳,并对其可行性、局限性及应用前景进行分析。

关键词：间充质干细胞肝纤维化细胞治疗

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Triggering heteroatomic interdiffusion in one-pot-oxidation synthesized NiO/CuFeO_(2) heterojunction photocathodes for efficient solar hydrogen production from water splitting

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Rare Metals 2023年第3期42卷 853-861页

作者： Fei Han Wei Xu chun-Xu Jia xiang-Tao chen Ying-Peng Xie Chao Zhen Gang Liu Key Laboratory of Resources Chemicals and Materials(Shenyang University of Chemical Technology) Ministry of EducationShenyang 110142China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China

Delafossite CuFeO_(2) is a promising photocathode material for cost-efficiently photoelectrochemical(PEC)water splitting,but the unfavorable conductivity and fast recombination dynamics of photogenerated carriers limit its PEC activity for water reduction.Here,we developed a heterostructure photocathode consisting of the Cu-doped NiO(Cu:NiO)hole selective layer(HSL)and Ni-doped CuFeO_(2)(Ni:CuFeO_(2))active layer by simply annealing a homogeneous Cu-Fe oxalate layer grown on the Ni film deposited on the fluorine doped tin oxide(FTO)substrate.The obtained heterostructure of Cu:NiO/Ni:CuFeO_(2) with enhanced charge carrier transportability and high-quality interface greatly promotes the separation of photogenerated carriers.Accordingly,the Cu:NiO/Ni:CuFeO_(2) photocathode exhibits a high photocurrent density of~0.9 mA·cm^(-2 )at 0.2 V(vs.reversible hydrogen electrode,RHE),outperforming most of the reported bare CuFeO_(2) photocathodes in the literature.And the photocurrent density can be further improved to 1.2 mA·cm^(-2) after decorating NiSx cocatalyst.

关键词： Photoelectrochemical(PEC)water splitting NiO/CuFeO_(2)hybrid photocathode Heteroatomic interdiffusion

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Enantioselective Diels-Alder reactions with left-handed G-quadruplex DNA-based catalysts

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Chinese Chemical Letters 2021年第5期32卷 1701-1704页

作者： Kun chen Zhiyong He Wei Xiong chun-Jiang Wang xiang Zhou College of Chemistry and Molecular Sciences Key Laboratory of Biomedical Polymers of Ministry of EducationWuhan UniversityWuhan 430072China

Since the discovery of left-handed G-quadruplex(L-G4)structure formed by natural DNA,there has been a growing interest in its potential functions.This study utilised it to catalyse enantioselective Diels-Alder reactions,considering its different optical rotation compared to an ordinary G4.It was determined that when L-G4 was used with a combination of copper(Ⅱ)ions,there was a good enantioselectivity(-52%ee)without further addition of ligands.When further consideration was given by adding G4 ligands,G4 was further stabilised,even obtaining a better enantioselectivity(up to-80%ee).Moreover,when using ligands that have regulatory effects on G4,the ee value can be adjusted.In this work,a minimal left-handed G4 was reported.A follow-up study was also con ducted,which recovers that the minimal left-handed G4 remains its catalytic effect and enantioselectivity,but is not so effective as the former case.This indicates that a complete G4 structure is relatively conducive to chiral catalysis.

关键词： Diels-Alder reaction Left-handed G-quadruplex Asymmetric catalysis Enantioselectiv ity G-quadruplex ligand

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Proprotein convertase 1/3-mediated down-regulation of brain-derived neurotrophic factor in cortical neurons induced by oxygen-glucose deprivation

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Neural Regeneration Research 2020年第6期15卷 1066-1070页

作者： xiang-Yang Zhang Feng Liu Yan chen Wei-chun Guo Zhao-Hui Zhang Department of Orthopedics Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Brain-derived neurotrophic factor(BDNF)has robust effects on synaptogenesis,neuronal differentiation and synaptic transmission and plasticity.The maturation of BDNF is a complex process.Proprotein convertase 1/3(PC1/3)has a key role in the cleavage of protein precursors that are directed to regulated secretory pathways;however,it is not clear whether PC1/3 mediates the change in BDNF levels caused by ischemia.To clarify the role of PC1/3 in BDNF maturation in ischemic cortical neurons,primary cortical neurons from fetal rats were cultured in a humidified environment of 95%N_2 and 5%CO_2 in a glucose-free Dulbecco's modified Eagle's medium at 37℃for3 hours.Enzyme-linked immunosorbent assays and western blotting showed that after oxygen-glucose deprivation,the secreted and intracellular levels of BDNF were significantly reduced and the intracellular level of PC1/3 was decreased.Transient transfection of cortical neurons with a PC1/3 overexpression plasmid followed by oxygen-glucose deprivation resulted in increased PC1/3 levels and increased BDNF levels.When levels of the BDNF precursor protein were reduced,the concentration of BDNF in the culture medium was increased.These results indicate that PC 1/3 cleavage of BDNF is critical for the conversion of pro-BDNF in rat cortical neurons during ischemia.The study was approved by the Animal Ethics Committee of Wuhan University School of Basic Medical Sciences.

关键词： cortical neuron ischemia neurotrophin oxygen-glucose deprivation precursor protein of brain-derived neurotrophic factor proprotein convertase proprotein convertase 1/3

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