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Frontiers of Environmental Science & Engineering 2009年第2期3卷 152-170页

作者： Lutz AHRENS Merle PLASSMANN zhiyong xie Ralf EBINGHAUS Institute for Coastal Research GKSS Research Centre Geesthacht GmbHD-21502 GeesthachtGermany Institute for Ecology and Environmental Chemistry Leuphana University of LüneburgD-21335 LüneburgGermany Department of Applied Environmental Science(ITM) Stockholm UniversitySE-10691 StockholmSweden

The distribution of polyfluoroalkyl compounds(PFCs)in the dissolved and particulate phase and their discharge from the river Elbe into the North Sea were *** PFCs quantified included C_(4)-C_(8) perfluorinated sulfonates(PFSAs),6∶2 fluorotelomer sulfonate(6∶2 FTS),C_(6) and C_(8) perfluorinated sulfinates(PFSiAs),C_(4)-C_(12) perfluorinated carboxylic acids(PFCAs),perfluoro-3,7-dimethyl-octanoic acid(3,7m_(2)-PFOA),perfluorooctane sulfonamide(FOSA),and n-ethyl perfluroctane sulfonamidoethanol(EtFOSE).PFCs were mostly distributed in the dissolved phase,where perfluorooctanoic acid(PFOA)dominated with 2.9–12.5 ng/*** the suspended particulate matter FOSA and perfluorooctane sulfonate(PFOS)showed the highest concentrations(4.0 ng/L and 2.3 ng/L,respectively).The total flux ofΣPFCs from the river Elbe was estimated to be 802 kg/year for the dissolved phase and 152 kg/year for the particulate *** indicates that the river Elbe acts as a source of PFCs into the North ***,the concentrations of perfluorobutane sulfonate(PFBS)and perfluorobutanoic acid(PFBA)in the North Sea were higher than that in the river Elbe,thus an alternative source must exist for these compounds.

关键词： polyfluoroalkyl compounds(PFCs) perfluorooctane sulfonate(PFOS) perfluorooctanoic acid(PFOA) surface water water-particulate partitioning

Structure of Graphene, and Mechanical and Bonding Characteristics of Single Wall Carbon Nanotube by Linear Scaling Quantum Mechanical Method

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Journal of Materials Science & Technology 2010年第7期26卷 614-618页

作者： Jun Cai Guiqin Li Chongyu Wang zhiyong xie School of Nuclear-Science & Engineering North China Electric Power University Beijing 102206 China Department of Physics Tsinghua University Beijing 100084 China Department of Materials Science & Engineering North China Electric Power University Beijing 102206 China

Using a linear scaling self-consistent-charge density functional tight binding （SCC-DFTB） and an ab initio Omol method, the bonding characteristics and Young＇s modulus of （10, 0） and （10,10） single-walled carbon nanotubes are calculated. The structure of a graphene is also calculated. It is found that the C-C and C-H bond length, their distribution characteristics on the tube, and Young^s modulus of the tube by linear scaling SCC-DFTB are identical to those by ab initio, while the computing cost by the linear scaling SCC-DFTB is reduced by more than 30 times as compared with that by the Dmol for the （10,0） and （10,10） tubes. By computing the structure of a graphene it is also found that the linear scaling SCCDFTB is reliable and time-saving.

关键词： Single walled nanotube tube Young's modulus Linear scaling method Density functional tight-binding

Microstructure Control of Nanoporous Silica Thin Film Prepared by Sol-gel Process

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Journal of Materials Science & Technology 2007年第4期23卷 504-508页

作者： Yiqun XIAO Jun SHEN zhiyong xie Bin ZHOU Guangming WU Pohl Institute of Solid State Physics Tongji University Shanghai 200092 China

Nanoporous silica films were prepared by sol-gel process with base, acid and base/acid two-step *** electron microscope （TEM） and particle size analyzer were used to characterize the microstructure and the particle size distribution of the sols. Scanning electron microscopy （SEM）, atomic force microscopy （AFM） and spectroscopic ellipsometer were used to characterize the surface microstructure and the optical properties of the silica films. Stability of the sols during long-term storage was investigated. Moreover,the dispersion relation of the optical constants of the silica films, and the control of the microstructure and properties of the films by changing the catalysis conditions during sol-gel process were also discussed.

关键词： Sol-gel Nanoporous Microstructure Optical constants Silica Thin Film

Bioaccumulation and changes of trace metals over the last two decades in marine organisms from Guangdong coastal regions, South China

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Journal of Environmental Sciences 2020年第12期32卷 103-108页

作者： Lulu Zhang Wen Yan zhiyong xie Guanqiang Cai Wenying Mi Weihai Xu Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Helmholtz-Zentrum Geesthacht Centre for Materials and Coastal ResearchInstitute of Coastal ResearchGeesthacht 21502Germany Guangzhou Marine Geological survey Guangzhou 510760China MINJIE Institute of Environmental Science and Health Research Geesthacht 21502Germany Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Science Beijing 100049China

Trace metal(Cr, Ni, Cu, Zn, Cd and Pb) exposures, distribution and bioaccumulation were investigated in marine organisms from Guangdong coastal regions, South China. The results showed that all of the selected metals were observed in marine organisms with a predomination of Cu and Zn. The metal exposure levels exhibited obvious variations between species with the decreasing order of crab > shellfish > shrimp > fish. The higher metals enrichment seen in shellfish and crab species primarily attributed to their living habits and the higher sediment background values of trace metals. Endpoint bioaccumulation factor(BAFfd) was used to characterize the bioaccumulation potentials of marine organisms to trace metals, of which Cu and Zn were the most accumulated elements. The exposure of trace metals in the cultured organisms was far lower than those in wild marine organisms, which is probably due to the effect of growth dilution. Comparisons with previous studies demonstrated that the concentration profiles of most trace metals declined over the last one to two decades, except Cu, that increased indistinctively.

关键词： Trace metal Bioaccumulation Marine organism South China

The differential requirement of mushroom body α/β subdivisions in long-term memory retrieval in Drosophila

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Protein & Cell 2013年第7期4卷 512-519页

作者： Cheng Huang Pengzhi Wang zhiyong xie Lianzhang Wang Yi Zhong School of Life Sciences Tsinghua UniversityBeijing 100084China Cold Spring Harbor Laboratory Cold Spring HarborNY 11724USA Present address:Department of Biological Sciences Stanford UniversityStanfordCA 94305USA Present address:Department of Bioengineering University of CaliforniaSan DiegoLa JollaCA 92093USA

The mushroom body(MB),a bilateral brain structure pos-sessing about 2000-2500 neurons per hemisphere,plays a central role in olfactory learning and memory in Dros-ophila *** studies have demonstrat-ed that three major types of MB neurons(α/β,α’/β’andγ)exhibit distinct functions in memory processing,including the critical role of approximately 1000 MBα/βneurons in retrieving long-term *** by recent fi ndings that MBα/βneurons can be further divided into three subdivisions(surface,posterior and core)and wherein theα/βcore neurons play an permissive role in long-term memory consolidation,we examined the functional differ-ences of all the three morphological subdivisions of MBα/βby temporally precise manipulation of their synaptic outputs during long-term memory *** found the normal neurotransmission from a combination of MBα/βsurface and posterior neurons is necessary for retrieving both aversive and appetitive long-term memory,whereas output from MBα/βposterior or core subdivision alone is *** results imply a specifi c requirement of about 500 MBα/βneurons in supporting long-term memory retrieval and a further functional partitioning for memory processing within the MBα/βregion.

关键词： memory retrieval neural circuits aversive olfactory conditioning appetitive olfactory conditioning mush-room body

Influence of Preparation Technology on the Structure and Phase Composition of MoSi_2-Mo_5Si_3 /SiC Multi-coating for Carbon/Carbon Composites

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Journal of Materials Science & Technology 2010年第2期26卷 106-112页

作者： Xin Yang Yanhong Zou Qizhong Huang Zhean Su Mingyu Zhang Xin Chang zhiyong xie State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China Materials Science and Engineering Post-doctoral Research Center Central South University Changsha 410083 China

Oxidation protective MoSi2-MosSi3/SiC multi-coatings for carbon/carbon composites were prepared by chemical vapor reaction and slurry-sintering method. The influence of preparation technology on the structure and phase composition of the coating was investigated by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD） analyses, and then their relationship was discussed. The results indicate that the Si/Mo ratio of the slurry and sintering processing were two main factors that significantly affected the structure and phase composition of the multi-coating. Appropriate sintering process and relatively high Si/Mo ratio were essential for preparing the multi-coating with dense structure and favorable phase composition. After being sintered at 1723 K for 2 h and with the Si/Mo ratio of the slurry being 4.5 （weight ratio）, a dense structure accompanied by favorable phase composition of the coating can be obtained. When heat treated at 2373 K for I h, this coating became more compact and continuous. Oxidation tests （performed at 1623 and 1823 K） demonstrated that both of these two obtained multi-coatings exhibited better anti-oxidation property than single layer SiC coating.

关键词： Carbon/carbon composites Anti-oxidation coating SiC

Performance of an elliptical crystal spectrometer for SGⅡX-ray opacity experiments

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High Power Laser Science and Engineering 2018年第1期6卷 13-19页

作者： Ruirong Wang Honghai An zhiyong xie Wei Wang Shanghai Institute of Laser Plasma Shanghai 201800 China

A new crystal spectrometer for application in X-ray opacity experiments is proposed. The conditions necessary to yield broad spectral coverage with a resolution >500, strong rejection of hard X-ray backgrounds and negligible source broadening for extended sources are formulated. In addition, the design, response modeling and reporting of an elliptical crystal spectrometer in conjunction with a linear detector are presented. The measured results demonstrate the performance of the new crystal spectrometer with a broad energy coverage range, high spectral resolution, and high luminosity(good collection efficiency). This spectrometer can be used in combination with point-projection backlighting techniques as utilized in X-ray opacity experiments. Specifically, the X-ray source, transmission and self-emission spectra of the sample can be measured simultaneously in a single shot, which can reduce the experimental uncertainties from shot-to-shot fluctuations. The new crystal spectrometer has been used in the X-ray opacity experiment to precisely measure the aluminum K-absorption edge shift in the energy range around 1.560 keV in strongly compressed matter. It is demonstrated that the spectrometer can be used to realize measurements of new and unpredictable physical interactions of interest, as well as basic and applied high-energy-density science.

关键词： high energy density physics inertial confinement fusion ultra-intense ultra-short pulse laser interaction with matters

Acceleration-Level Inverse-Free G2 Scheme for Inverse Kinematics Path Tracking of Robot Manipulators 36

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Acceleration-Level Inverse-Free G2 Scheme for Inverse Kinema...

2-O-β-D-Glucopyranosyl-L-ascorbic acid,an ascorbic acid derivative isolated from the fruits of Lycium barbarum L.,ameliorates high fructose-induced neuroinflammation in mice:involvement of gut microbiota and leaky gut

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作者： Jiawei Luo Jun Zhang zhiyong xie Xiaoyin Zhang Lin Xiao Xiao Su Pingxiang University Jiangxi Vocational College of Industry and Engineering College of Information Science and Engineering Jishou University

ISBN: (纸本)9781538629185

The mature analysis formula has been well used in the robotic forward kinematics for redundant manipulators,but the inverse-kinematics（IK） question is *** methods have been adopted to resolve the complicated inverse-kinematics problem;for example,the previous pseudo-inverse based（PIB） method that have to calculate the computationally expensive inverse（specifically,pseudo-inverse） of Jacobian ***,this method brings a lot of defects and *** that,to drastically avoid the Jacobian inversion and also to obtain the accurate solution of the time-varying IK problem for redundant robot manipulators,it is necessary to indagate other inverse-kinematics schemes through applying the related dynamic *** on many previously excellent researches,the dynamic methods used in this paper consist of gradient dynamics（GD）.By using GD kinematic method twice,a scheme called G2 is studied for solving the redundancy question of robot manipulators in an inverse-free *** a representative application of GD method,the G2 scheme,which is exploited at the acceleration level instead of the velocity ***,we conduct the end-effector path-tracking simulations performed on planar robot manipulators of different links to substantiate the effectiveness and accuracy of the proposed inverse-free G2 *** results illustrate the physical reahzability of the proposed novel solution for handling the time-varying IK problem of the redundant robot manipulator（s） in an inverse-free manner.

关键词： Inverse Kinematics Question Gradient Dynamics Inverse-Free G2 Scheme Redundant Manipulators PathTracking

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Food Science and Human Wellness 2024年第1期13卷 241-253页

作者： Wei Dong Yujia Peng Guijie Chen zhiyong xie Weiqi Xu Wangting Zhou Jia Mi Lu Lu Yi Sun Xiaoxiong Zeng Youlong Cao Yamei Yan College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095China Institute of Wolfberry Engineering Technology National Wolfberry Engineering Research CenterNingxia Academy of Agriculture and Forestry SciencesYinchuan 750002China

Western diet(rich in highly refined sugar and fat)can induce a range of metabolic dysfunctions in animals and humans,including neuroinflammation and cognitive function *** and cognitive impairment,two critical pathological characteristics of Alzheimer’s disease,have been closely associated with microbial alteration via the gut-brain ***,the present study aimed to investigate the influence of 2-O-β-D-glucopyranosyl-L-ascorbic acid(AA-2βG)isolated from the fruits of Lycium barbarum on preventing the high-fructose diet(HFrD)induced neuroinflammation in *** was found that AA-2βG prevented HFr D-induced cognitive ***-2βG also predominantly enhanced the gut barrier integrity,decreased lipopolysaccharide entry into the circulation,which subsequently countered the activation of glial cells and neuroinflammatory *** beneficial effects were transmissible by horizontal fecal microbiome transplantation,transferring from AA-2βG fed mice to HFr D fed ***,AA-2βG exerted neuroprotective effects involving the enrichment of Lactobacillus and Akkermansia,potentially beneficial intestinal *** present study provided the evidence that AA-2βG could improve indices of cognition and neuroinflammmation via modulating gut dybiosis and preventing leaky *** a potential functional food ingredient,AA-2βG may be applied to attenuate neuroinflammation associated with Western-style diets.

关键词： Neuroinfl ammation Gut microbiota Leaky gut Lipopolysaccharide Fecal microbiome transplantation 2-O-β-D-Glucopyranosyl-L-ascorbic acid

Organophosphate Esters in Air and Seawater of the South China Sea:Spatial Distribution,Transport,and Air−Sea Exchange

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Environment & Health 2023年第3期1卷 191-202页

作者： Lijie Mi zhiyong xie Lulu Zhang Joanna J.Waniek Thomas Pohlmann Wenying Mi Weihai Xu Institute of Coastal Environmental Chemistry Helmholtz-Zentrum HereonGeesthacht 21502Germany Institute of Oceanography University of HamburgHamburg 20146Germany Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Sanya Institute of Ocean Eco-Environmental Engineering Sanya 572000China University of Chinese Academy of Sciences Beijing 100049China Department of Marine Chemistry Leibniz Institute for Baltic Sea Research WarnemündeRostock 18119Germany MINJIE Institute of Environmental Science and Health Research Geesthacht 21502Germany

Organophosphate esters(OPEs)have become one group of chemicals with emerging concern in the marine *** this work,we investigated OPEs in the air and seawater of the South China Sea in summer *** concentrations of∑_(10)OPEs in the atmosphere ranged from 66 to 550 pg/m^(3),with TCIPP,TNBP,TPhP,and TEP predominating in the *** total dissolved OPE concentrations(∑_(10)OPEs without TEP)measured in high-volume water samples ranged from 300 to 3600 pg/L,with a mean concentration of 1180±910 pg/*** was measured with liquid−liquid extraction(LLE),and it showed the highest concentration(average 2000±1450 pg/L)among the selected *** suspended matter associated OPEs accounted for less than 4.7%of the sum of OPE concentrations in *** fractions and air−sea exchange fluxes showed that TCEP,TCIPP,TIBP,TEHP,TPhP,and EHDPP were favored to volatilize,TEP dominated the deposition,while TPrP and TNBP varied between volatilization and *** particle deposition fluxes ranged from 5 to 71 ng/m^(2)/day with an average of 17±15 ng/m^(2)/*** input of∑OPEs to the entire South China Sea via atmospheric particle deposition was estimated to be 22±19 tons/year,while the net air−sea exchange fluxes of OPEs were volatilization from seawater to air with an average of 44±33 tons/*** work suggests that air−sea exchange and atmospheric particle deposition are significant processes interfering with the transport of OPEs in the marine environment.

关键词： Organophosphate esters South China Sea Air−sea exchange Atmospheric deposition Long-range transport