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Chinese Chemical Letters 2014年第4期25卷 505-510页

作者： Yuan-Yuan Yao Long Zhang zi-fei Wang Jing-Kun xu Yang-Ping Wen Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University College of Science Jiangxi Agricultural University

A simple and sensitive platinum nanoparticles/poly（hydroxymethylated-3,4-ethylenedioxylthiophene） nanocomposite （PtNPs/PEDOT-MeOH） modified glassy carbon electrode （GCE） was successfully developed for the electrochemical determination of quercetin. Scanning electron microscopy and energy dispersive X-ray spectroscopy results indicated that the PtNPs were inserted into the PEDOT- MeOH layer. Compared with the bare GCE and poly（3,4-ethylenedioxythiophene）（PEDOT） electrodes, the PtNPs/PEDOT-MeOH/GCE modified electrode exhibited a higher electrocatalytic ability toward the oxidation of quercetin due to the synergic effects of the electrocatalytic activity and strong adsorption ability of PtNPs together with the good water solubility and high conductivity of PEDOT-MeOH. The electrochemical sensor can be applied to the quantification of quercetin with a linear range covering 0.04-91μmol L-1 and a low detection limit of 5.2 nmol L-1. Furthermore, the modified electrode also exhibited good reoroducibilitv and long-term stability, as well as high selectivity.

关键词： Poly( 3 4-ethylenedioxylthiophene methanol) Platinum nanoparticles Electropolymerization Differential pulse voltammetryQuercetin

Synthesis and Characterization of Tungsten Doped Vanadium Dioxide Nanopowders by Thermolysis

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Chinese Chemical Letters 2006年第10期17卷 1417-1420页

作者： zi fei PENG Wei JIANG Department of Chemistry Shanghai Normal University Shanghai 200234

As far as we known, with white powdery tungstic acid （WPTA） used as the dopant for the first time, tungsten-doped vanadium dioxide （VO2） nanopowders were synthesized through thermolysis at low temperature. The products were characterized by XRD, TEM and DSC. When WPTA was added into V205 （with W/V = 2 atom %）, the phase transition temperature （Tc） of VO2 decreased markedly from 67.15℃ to 26.46℃ after annealing at 500℃. Such a low Tc is beneficial to the application and development of smart windows materials.

关键词： Vanadium dioxide white powdery tungstic acid phase transition thermolysis

Infinitely Many Solutions for a Class of Fourth Order Elliptic Equations in R^N

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Acta Mathematica Sinica,English Series 2008年第8期24卷 1269-1278页

作者： Min Bo YANG zi fei SHEN Department of Mathematics Zhejiang Normal University Jinhua 321004 P. R. China

With the aids of variational method and concentration-compactness principle, infinitely many solutions are obtained for a class of fourth order elliptic equations with singular potentialΔ^2u=μ｜u｜^2＊＊（s）-2u/｜x... 详细信息

关键词： biharmonic operator Hardy-Sobolev critical exponent Palais-Smale condition

New lobane-type diterpenoids from the Xisha soft coral Sinularia polydactyla

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Chinese Journal of Natural Medicines 2020年第11期18卷 839-843页

作者： YE fei CHEN zi-Hui GU Yu-Cheng GUO Yue-Wei LI xu-Wen State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203.China Open Studio for Druggability Research of Marine Natural Products Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237.China University of Chinese Academy of Sciences Beijing 100049China Syngenta Jealott's Hill International Research CentreBracknellBerkshire RG426EYUnited Kingdom

Lobane-type diterpenoids are not frequently discovered from marine soft corals. In this paper, three new lobane type diterpenes, 13-methoxyloba-8,10,15(16),17(18)-tetraene(1), 8,10,13(15)Z,16 E-lobatetraene(2) and 19-hydroxy-lobatetraene(3), and a new natural compound, 17,18-epoxyloba-16-acetoxy-8,10,13(15)-trien(4), co-occurring with a known related diterpenoid, 18-methoxyloba-8,10,13(15),16(17)-tetraene(5), were isolated from the South China Sea soft coral Sinularia polydactyla. The structures of new compounds were determined by extensive spectroscopic analysis and by comparison with those reported in the literature. In bioassay, all the isolates were inactive on antibacterial, PTP1 B inhibitory, and immunological activities. This study increased the chemical diversity of marine diterpenoids.

关键词： Soft coral Sinularia polydactyla Lobane Diterpenes

The Rearrangement of 2-Benzothiazolylthioacetyl Hydrazide in Synthesis of s-Triazolo[3,4-b]benzothiazole-3-thiol

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Chinese Chemical Letters 2002年第4期13卷 287-289页

作者： Yan ZHANG Ren Zhong QIAO Chao Feng DAI Peng fei xu zi Yi ZHANG National Laboratory of Applied Organic Chemistry Department of ChemistryLanzhou UniversityLanzhou 730000

The rearrangement reaction of 2-benzothiazolylthioacetyl hydrazide 1 with potassium hydroxide and carbon disulfide in ethanol to produce s-triazolo[3, 4-b]benzothiazole-3-thiol 3 was described. 3 also can be obtained from 2-benzothiazolylhydazine 2 and the two methods for getting 3 were compared. Mannich reaction of compounds 3 was reported too.

关键词： Rearrangement s-triazolo[3, 4-b]benzothiazole-3-thiol Mannich reaction.

Predictive value of red blood cell distribution width and hematocrit for short-term outcomes and prognosis in colorectal cancer patients undergoing radical surgery

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World Journal of Gastroenterology 2024年第12期30卷 1714-1726页

作者： Dong Peng zi-Wei Li fei Liu xu-Rui Liu Chun-Yi Wang Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Previous studies have reported that low hematocrit levels indicate poor survival in patients with ovarian cancer and cervical cancer,the prognostic value of hematocrit for colorectal cancer(CRC)patients has not been *** prognostic value of red blood cell distribution width(RDW)for CRC patients was *** To investigate the impact of RDW and hematocrit on the short-term outcomes and long-term prognosis of CRC patients who underwent radical *** Patients who were diagnosed with CRC and underwent radical CRC resection between January 2011 and January 2020 at a single clinical center were *** short-term outcomes,overall survival(OS)and disease-free survival(DFS)were compared among the different *** analysis was also conducted to identify independent risk factors for OS and *** There were 4258 CRC patients who underwent radical surgery included in our study.A total of 1573 patients were in the lower RDW group and 2685 patients were in the higher RDW *** were 2166 and 2092 patients in the higher hematocrit group and lower hematocrit group,*** in the higher RDW group had more intraoperative blood loss(P<0.01)and more overall complications(P<0.01)than did those in the lower RDW ***,patients in the lower hematocrit group had more intraoperative blood loss(P=0.012),longer hospital stay(P=0.016)and overall complications(P<0.01)than did those in the higher hematocrit *** higher RDW group had a worse OS and DFS than did the lower RDW group for tumor node metastasis(TNM)stage I(OS,P<0.05;DFS,P=0.001)and stage II(OS,P=0.004;DFS,P=0.01)than the lower RDW group;the lower hematocrit group had worse OS and DFS for TNM stage II(OS,P<0.05;DFS,P=0.001)and stage III(OS,P=0.001;DFS,P=0.001)than did the higher hematocrit *** hematocrit was an independent risk factor for OS[P=0.017,hazard ratio(HR)=1.256,95%confidence interval(CI):1.041-1.515]and DFS(P=0.035,HR=1.194

关键词： Colorectal cancer Red blood cell distribution width Survival Short-term outcomes

A kinetic study and factor analysis of solar thermochemical membrane reactors for syngas production

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Science China Technological Sciences 2025年第1期 207-221页

作者： Jiaxin XING Chao xu Xiangyu SUN Xin XIA fei JIN Qiongqiong JIANG Jiale GAO Key Laboratory of Power Station Energy Transfer Conversion and System of MOE School of Energy Power and Mechanical EngineeringNorth China Electric Power University Department of Chemistry University College London School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyState Ethnic Affairs CommissionNorth Minzu University

Solar thermochemical conversion technologies are promising for effectively utilizing solar energy by capturing the full spectrum of solar radiation. To overcome the challenges of low energy conversion efficiency and intermittency faced by solar thermochemical conversion, these technologies can be effectively integrated with membrane reactor technology. Although the performance of solar thermochemical membrane reactors has been experimentally tested, the chemical reactions and oxygen transport mechanisms during the energy conversion process remain poorly understood. This study introduces a resistance network model to elucidate the interactions between interfacial reactions and bulk diffusion during simultaneous oxidationreduction reactions on both sides of the membrane. We analyzed the oxygen flux of the membrane reactor under various operating conditions using this model to identify the reaction/transport-limiting side of the overall process. The most effective solar membrane reactor configuration utilizes natural gas and CO2, facilitating clean conversion of fossil fuels with significant advantages in fuel production and energy efficiency. Introducing CH4lowers the overall reaction temperature, maintains low oxygen partial pressure on the sweep side, and produces a synthesis gas with a 2:1 H2/CO molar ratio. Finally, a sensitivity analysis was used to explore the relationship between overall fuel production performance and operational parameters,highlighting the critical role of this research in enhancing the reaction and transport performance of membrane reactors and advancing the development of solar-driven thermochemical fuel production technologies.

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The Decay Rate of Patterson–Sullivan Measures with Potential Functions and Critical Exponents

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Acta Mathematica Sinica,English Series 2019年第12期35卷 1937-1944页

作者： zi Qiang FENG fei LIU Fang WANG College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590P.R.China School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China

Basing upon the recent development of the Patterson–Sullivan measures with a H¨older continuous nonzero potential function,we use tools of both dynamics of geodesic flows and geometric properties of negatively curved manifolds to present a new formula illustrating the relation between the exponential decay rate of Patterson–Sullivan measures with a H¨older continuous potential function and the corresponding critical exponent.

关键词： Geodesic flows Patterson-Sullivan measures critical exponent

Numerical and experimental study on the response characteristics of warhead in the fast cook-off process

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Defence Technology（防务技术） 2021年第4期17卷 1444-1452页

作者： Min Zhu Sheng-ao Wang Huang Huang Gui Huang fei Wu Shao-hua Sun Biao Li zi-jian xu College of Nuclear Science and Technology Naval University of EngineeringWuhan430033China

The response characteristics of the warhead under thermal stimuli conditions are important to the safety *** goal of this study is to obtain data on the warhead in the fast cook-off *** this paper,a numerical calculation method is proposed,whose reliability is supported by comparison with experimental *** the numerical calculation,the temperature distribution,temperature change,and ignition time are *** numerical results show that the ignition time is 76 s after the warhead started to burn and that the maximum temperature of the explosive’s outer surface is 238.3℃ at the ignition *** fast cook-off experiment of the warhead is implemented so as to get the flame temperature and reaction grades that are not available through numerical *** experimental results show that the overpressure fails to reach the preset minimumvalue which is equivalent to 6 kg of TNT and that the reaction grade is *** research results have reference value for the design of the warhead and the reduction of detonation risks.

关键词： Warhead Explosives Fast cook-off Numerical calculations

Gait Analysis of Quadruped Robot Using the Equivalent Mechanism Concept Based on Metamorphosis

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Chinese Journal of Mechanical Engineering 2019年第1期32卷 31-41页

作者： Kun xu Peijin zi Xilun Ding Robotics Institute School of Mechanical Engineering & Automation Beihang University

The previous research regarding the gait planning of quadruped robot focuses on the sequence for lifting o and placing the feet, but neglects the influence of body height. However, body height a ects gait performance significantly, such as in terms of the stride length and stability margin. We herein study the performance of a quadruped robot using the equivalent mechanism concept based on metamorphosis. Assuming the constraints between standing feet and the ground with hinges, the ground, standing legs and robot body are considered as a parallel mechanism, and each swing leg is regarded as a typical serial manipulator. The equivalent mechanism varies while the robot moves on the ground. One gait cycle is divided into several periods, including step forward stages and switching stages. There exists a specific equivalent mechanism corresponding to each gait period. The robot's locomotion can be regarded as the motion of these series of equivalent mechanisms. The kinematics model and simplified model of the equivalent mechanism is established. A new definition of the multilegged robot stability margin, based on friction coe cient, is presented to evaluate the robot stability. The stable workspaces of the equivalent mechanism in the step forward stage of trotting gait under di erent friction coe cients are analyzed. The stride length of the robots is presented by analyzing the relationship between the stable workspaces of the equivalent mechanisms of two adjacent step forward stages in one gait cycle. The simulation results show that the stride length is larger with increasing friction coe cient. We herein propose a new method based on metamorphosis, and an equivalent mechanism to analyze the stability margin and stable workspace of the multilegged robot.

关键词： Quadruped robot Gait transference Metamorphosis Metamorphic mechanism Stability Stride length