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Toward deeper development of Biogeochemical-Argo floats

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Atmospheric and Oceanic Science Letters 2018年第3期11卷 287-290页

作者： xing xiao-Gang CLAUSTRE Hervé BOSS Emmanuel CHAI Fei Second Institute of Oceanography State Oceanic AdministrationHangzhouChina Laboratoire d'Océanographie de Villefranche Sorbonne UniversitésVillefranche-sur-MerFrance School of Marine Sciences University of MaineOronoMEUSA

The Biogeochemical-Argo （BGC-Argo） Program aims at operating a network of profiling floats equipped with sensors of key biogeochemical variables for support- ing research activities that address impacts of climate c... 详细信息

关键词： BiogeochemicaI-Argo Argo project marine biogeochemistry phytoplankton dissolved oxygen nitrate pH particle

A NEW WAKE OSCILLATOR MODEL FOR PREDICTING VORTEX INDUCED VIBRATION OF A CIRCULAR CYLINDER

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Journal of Hydrodynamics 2010年第3期22卷 381-386页

作者： XU Wan-hai WU Ying-xiang, ZENG xiao-hui ZHONG xing-fu YU Jian-xing Key Laboratory of Port and Ocean Engineering Tianjin University Tianjin 300072 China Key Laboratory for Hydrodynamics and Ocean Engineering Institute of Mechanics Chinese Academy ofSciences Beijing 100190 China Key Laboratory of Port and Ocean Engineering Tianjin University Tianjin 300072 China

This article proposes a new wake oscillator model for vortex induced vibrations of an elastically supported rigid circular cylinder in a uniform current. The near wake dynamics related with the fluctuating nature of vortex shedding is modeled based on the classical van der Pol equation, combined with the equation for the oscillatory motion of the body. An appropriate approach is developed to estimate the empirical parameters in the wake oscillator model. The present predicted results are compared to the experimental data and previous wake oscillator model results. Good agreement with experimental results is found.

关键词： vortex induced vibration wake oscillator model circular cylinder van der Pol equation

Fe-N-C core-shell catalysts with single low-spin Fe(Ⅱ)-N_(4)species for oxygen reduction reaction and high-performance proton exchange membrane fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 538-546,I0013页

作者： Yan Wan Linhui Yu Bingxin Yang Caihong Li Chen Fang Wei Guo Fang-xing xiao Yangming Lin Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021FujianChina CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021FujianChina Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002FujianChina College of Materials Science and Engineering Fuzhou UniversityNew CampusMinhou 350108FujianChina College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117FujianChina

Fe-N-doped carbon materials(Fe-N-C)are promising candidates for oxygen reduction reaction(ORR)relative to Pt-based catalysts in proton exchange membrane fuel cells(PEMFCs).However,the intrinsic contributions of Fe-N_(4)moiety with different chemical/spin states(e.g.D1,D2,D3)to ORR are unclear since various states coexist *** the present work,Fe-N-C core-shell nanocatalyst with single lowspin Fe(Ⅱ)-N_(4)species(D1)is synthesized and identified with ex-situ ultralow temperature Mossbauer spectroscopy(T=1.6 K)that could essentially differentiate various Fe-N_(4)states and invisible Fe-O *** quantifying with CO-pulse chemisorption,site density and turnover frequency of Fe-N-C catalysts reach 2.4×10^(-9)site g^(-1)and 23 e site~(-1)s^(-1)during the ORR,***-wave potential(0.915V_(RHE))of the Fe-N-C catalyst is more positive(approximately 54 mV)than that of Pt/***,we observe that the performance of PEMFCs on Fe-N-C almost achieves the 2025 target of the US Department of Energy by demonstrating a current density of 1.037 A cm^(-2)combined with the peak power density of 0,685 W cm^(-2),suggesting the critical role of Fe(Ⅱ)-N_(4)site(D1).After 500 h of running,PEMFCs still deliver a power density of 1.26 W cm^(-2)at 1.0 bar H_(2)-O_(2),An unexpected rate-determining step is figured out by isotopic labelling experiment and theoretical *** work not only offers valuable insights regarding the intrinsic contribution of Fe-N_(4)with a single spin state to alkaline/acidic ORR,but also provides great opportunities for developing high-performance stable PEMFCs.

关键词： Fuel cells Oxygen reduction reaction Non-platinum group metals(PGMs) Isotopic labelling Active site TOF

Clinical application value of long non-coding RNAs signatures of genomic instability in predicting prognosis of hepatocellular carcinoma

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2386-2392页

作者： xiao-Wen xing xiao Huang Wei-Peng Li Ming-Ke Wang Ji-Shun Yang Department of Disease Control and Prevention Naval Medical CenterNaval Medical UniversityShanghai 200052China Medical Care Center Naval Medical UniversityShanghai 200052China

Hepatocellular carcinoma(HCC)presents challenges due to its high recurrence and metastasis rates and poor *** current clinical diagnostic and prognostic indicators exist,their accuracy remains imperfect due to their biol-ogical ***,there is a quest to identify improved biomarkers for HCC diagnosis and *** combining long non-coding RNA(lncRNA)expression and somatic mutations,Duan et al identified five representative lncRNAs from 88 lncRNAs related to genomic instability(GI),forming a GI-derived lncRNA signature(LncSig).This signature outperforms previously re-ported LncSig and TP53 mutations in predicting HCC *** this editorial,we comprehensively evaluate the clinical application value of such prognostic evaluation model based on sequencing technology in terms of cost,time,and ***,we provide an overview of various prognostic models for HCC,aiding in a comprehensive understanding of research progress in pro-gnostic evaluation methods.

关键词： Hepatocellular carcinoma Prognosis Prognostic model Biomarkers Genomic instability long non-coding RNA Clinical application value

Poly(vinylidene fluoride) membrane based thin film microextraction for enrichment of benzoylurea insecticides from water samples followed by their determination with HPLC

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Chinese Chemical Letters 2014年第12期25卷 1625-1629页

作者： Chen-Huan Wang xiao-xing Ma Chun Wang Qiu-Hua Wu Zhi Wang College of Science Agricultural University of Hebei No 1 High School of Baoding

Thin-film microextraction（TFME）,a new geometry for solid-phase microextraction,has become an attractive sample-preparation *** to other microextraction approaches,the sensitivity of this technique was enhanced without sacrificing the sampling time due to the high surface area-tovolume ratio together with the increase of extraction-phase *** this paper,a new TFME method based on poly（vinylidene fluoride） membrane was developed for the extraction of benzoylurea insecticides（diflubenzuron,triflumuron,hexaflumuron and teflubenzuron） from water samples followed by their determination with high performance liquid chromatography-diode array *** the optimal conditions,good linearity was observed over the concentration range of 0.5-100.0 ng/mL with correlation coefficient greater than *** limits of detection（S/N = 3） of the method for the target analytes were 0.1 ng/*** recoveries ranged from 87.7% to 103.9% with relative standard deviations lower than 6.5%.The results indicated that the developed TFME method is simple,efficient,and cost effective.

关键词： Thin film microextraction Poly(vinylidene fluoride) membrane Benzoylurea insecticides High performance liquid chromatography

Mesenchymal stem cells from human umbilical cord ameliorate testicular dysfunction in a male rat hypogonadism model

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Asian Journal of Andrology 2017年第5期19卷 543-547页

作者： Zhi-Yuan Zhang xiao-Yu xing Guan-Qun Ju Liang Zhong Jie Sun Department of Urology Shanghai Children's Medical Center Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200127 China.

Androgen deficiency is a physical disorder that not only affects adults but can also jeopardize children＇s health. Because there are many disadvantages to using traditional androgen replacement therapy, we have herein attempted to explore the use of human umbilical cord mesenchymal stem cells for the treatment of androgen deficiency. We transplanted CM-Dil-labeled human umbilical cord mesenchymal stem cells into the testes of an ethane dimethanesulfonate （EDS）-induced male rat hypogonadism model. Twenty-one days after transplantation, we found that blood testosterone levels in the therapy group were higher than that of the control group （P= 0.037）, and using immunohistochemistry and flow cytometry, we observed that some of the CM-Dil-labeled cells expressed Leydig cell markers for cytochrome P450, family 11, subfamily A, polypeptide 1, and 3-β-hydroxysteroid dehydrogenase. We then recovered these cells and observed that they were still able to proliferate in vitro. The present study shows that mesenchymal stem cells from human umbilical cord may constitute a promising therapeutic modality for the treatment of male hypogonadism patients.

关键词： Leydig cells stem cells testicular dysfunction

Infrared Photodissociation Spectroscopy of Ti＋（CO2）2Ar and Ti＋（CO2）n （n=3-7） Complexes

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Chinese Journal of Chemical Physics 2013年第6期26卷 687-693,I0004页

作者： xiao-peng xing Guan-jun Wang Cai-xia Wang Ming-fei Zhou Department of Chemistry Tongji University Shanghai 200092 China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysts and Innovative MaterialsFudan University Shanghai 200433 China

Ti＋（CO2）2Ar and Ti＋（CO2）n （n=3-7） complexes are produced by laser vaporization in a pulsed supersonic expansion. The ion complexes of interest are each mass-selected in a time- of-flight spectrometer, and studied with infrared photodissociation spectroscopy. For each complex, a sharp band in the CO stretching frequency region is observed, which confirms the formation of the OTi＋CO（CO2）~_l oxide-carbonyl species. Small OTi＋CO（CO2）~_1 complexes （n_〈5） exhibit CO stretching and antisymmetric CO2 stretching vibrational bands that are blue-shifted from those of free CO and CO2. The experimental observations indicate that the coordination number of CO and CO2 molecules around TiO＋ is five. Evidence is also observed for the presence of another electrostatic bonding Ti＋（CO2）2 structural isomer for the Ti＋（CO2）2Ar complex, which is characterized to have a bent OCO-Ti＋-OCO structure stabilized by argon coordination.

关键词： Infrared photodissociation spectroscopy Carbon dioxide complex Titanium Insertion reaction Density functional calculation

Estimation of lunar FeO abundance based on imaging by LRO Diviner

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Research in Astronomy and Astrophysics 2016年第2期16卷 27-32页

作者： xiao Tang xiao-xing Luo Yun Jiang Ao-Ao Xu Zhen-Chao Wang Xue-Wei Zhang Yuan Chen xiao-Meng Zhang Wei Cai Yun-Zhao Wu School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China Key Laboratory of Planetary Sciences Chinese Academy of SciencesNanjing 210008China East China Mineral Exploration and Development Bureau Nanjing 210007China Macao University of Science and Technology MacaoChina School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Understanding the abundance and distribution characteristics of FeO on the surface of the Moon is important for investigating its evolution. The current high resolution maps of the global FeO abundance are mostly produced with visible and near infrared reflectance spectra. The Christiansen Feature （CF） in mid-infrared has strong sensitivity to lunar minerals and correlates to major elements composing minerals. This paper investigates the possibility of mapping global FeO abundance using the CF values from the Diviner Lunar Radiometer Experiment aboard the Lunar Reconnaissance Orbiter （LRO） mission. A high correlation between the CF values and FeO abundances from the Apollo samples was found. Based on this high correlation, a new global map （±60°） of FeO was produced using the CF map. The results show that the global FeO average is 8.2 wt.%, the highland average is 4.7 wt.%, the global modal abundance is 5.4 wt.% and the lunar mare mode is 15.7 wt.%. These results are close to those derived from data provided by Clementine, the Lunar Prospector Gamma Ray Spectrometer （LP-GRS） and the Chang＇e-1 Interference Imaging Spectrometer （IIM）, demonstrating the feasibility of estimating FeO abundance based on the Diviner CF data. The near global FeO abundance map shows an enrichment of lunar major elements.

关键词： astrochemistry -- planets and satellites detection -- methods data analysis -- infrared general

HYDRODYNAMIC ANALYSIS AND SIMULATION OF A SWIMMING BIONIC ROBOT TUNA

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Journal of Hydrodynamics 2007年第4期19卷 412-420页

作者： CHEN Hong ZHU Chang-an YIN Xie-zhen xing xiao-zheng CHENG Gang College of Mechatronics and Control Engineering Shenzhen University Shenzhen 518060 China School of Engineering Science University of Science and Technology of China Hefei 230027 China

A dynamic model for undulatory locomotion was proposed to study the swimming mechanism of a developed bionic robot tuna. On the basis of inviscid hydrodynamics and rigid-body dynamics, the momentum and propulsive force required for propelling the swimming robot tuna＇s flexible body was calculated. By solving the established dynamic equations and efficiency formula, the swimming velocity and propulsive efficiency of the bionic robot tuna were obtained. The relationship between the kinematic parameters of the robot tuna＇s body curve and the hydrodynamic performances was established and discussed after hydrodynamic simulations. The results presented in this article can be used to increase the swimming speed, propulsive thrust, and the efficiency of underwater vehicles effectively.

关键词： undulatory locomotion swimming propulsive force efficiency body curve hydrodynamic simulations