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石墨烯修饰电极同时测定邻苯二酚和对苯二酚

武汉工程大学学报 2013年第2期35卷 16-23页

作者：万其进廖华玲刘义魏薇舒好杨年俊武汉工程大学绿色化工过程教育部重点实验室湖北省新型反应器与绿色化学工艺重点实验室湖北武汉430074

制备石墨烯玻碳修饰电极,进而采用循环伏安法、交流阻抗等电化学方法对该电极进行表征,研究该石墨烯修饰电极在邻苯二酚和对苯二酚上的电化学行为.结果表明,在石墨烯修饰电极上邻苯二酚的氧化峰电位和还原峰电位分别是270mV和161mV,对... 详细信息

制备石墨烯玻碳修饰电极,进而采用循环伏安法、交流阻抗等电化学方法对该电极进行表征,研究该石墨烯修饰电极在邻苯二酚和对苯二酚上的电化学行为.结果表明,在石墨烯修饰电极上邻苯二酚的氧化峰电位和还原峰电位分别是270mV和161mV,对苯二酚氧化峰电位和还原峰电位分别是145mV和64mV,由于邻苯二酚和对苯二酚的氧化峰电位大约相离125mV,还原峰大约相离97mV,因此适合同时检测邻苯二酚和对苯二酚.邻苯二酚和对苯二酚的浓度在5.0×10-6～1.0×10-4 mol/L范围内与峰电流分别呈良好的线性关系;且在8.0×10-5～1.0×10-3 mol/L范围能同时检测邻苯二酚和对苯二酚,邻苯二酚的检测限可达5.0×10-7 mol/L,对苯二酚的检测限可达1.0×10-7 mol/L.该石墨烯修饰电极可作为电化学传感器用于邻苯二酚和对苯二酚的含量同时测定及环境水体中实际样品的分析.

关键词：石墨烯修饰电极示差脉冲法邻苯二酚对苯二酚

电纺聚乙烯醇纳米纤维膜无酶过氧化氢传感器的制备

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武汉工程大学学报 2013年第8期35卷 7-12页

作者：万其进尚艳利汪召豪崔晗杨年俊武汉工程大学绿色化工过程教育部重点实验室湖北省新型反应器与绿色化学工艺重点实验室湖北武汉430074

用静电纺丝的方法将聚乙烯醇(PVA)静电纺丝到裸铂电极表面,分别采用扫描电镜法、循环伏安法、电流时间曲线法、交流阻抗等方法对该电极进行表征.研究了过氧化氢在该聚乙烯醇修饰电极的电化学行为.实验结果表明:聚乙烯醇纳米纤维膜呈现... 详细信息

用静电纺丝的方法将聚乙烯醇(PVA)静电纺丝到裸铂电极表面,分别采用扫描电镜法、循环伏安法、电流时间曲线法、交流阻抗等方法对该电极进行表征.研究了过氧化氢在该聚乙烯醇修饰电极的电化学行为.实验结果表明:聚乙烯醇纳米纤维膜呈现出理想的疏松多孔的网状结构,极大地增大了电极的有效表面积;在pH=7.4的磷酸盐缓冲溶液中相比裸铂电极,聚乙烯醇纳米纤维膜修饰电极对过氧化氢的响应电流有明显的提高,过氧化氢的浓度在7.8～2 900μmol/L范围内,与其还原电流呈良好的线性关系,检测限达1.1μmol/L.该聚乙烯醇修饰电极可以作为电化学无酶传感器用于低浓度过氧化氢的检测.

关键词：聚乙烯醇静电纺丝修饰电极过氧化氢

A New Disaccharide from the Fern Macrothelypteris digophlebia

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Chinese Chemical Letters 2000年第12期11卷 1063-1064页

作者： Ming Hua qiU jin Ming GAO Hu qi LIU Jian Xi FU Kunming Institute of Botany The Chinese Academy of SciencesKunming 650204 Northwest Sci.&Tech.University of Agriculture and Forestry YanglingShaanxi 712100

A new disaccharide, digobiose 1, was isolated from the rhizomes of Macrothelypteris digophlebia (Bak.) Ching var. elegans (koidz.). Its structure which is very similar with that of sucrose was identified as alpha -D-g... 详细信息

关键词： Digobiose Disaccharide Macrothelypteris digophlebia

Symptomatic and optimal supportive care of critical COVID-19:A case report and literature review

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World Journal of Clinical Cases 2020年第23期8卷 6181-6189页

作者： qi-Lin Pang Wen-Cheng He jin-Xiu Li Lei Huang Department of Intensive Care Unit The Third People’s Hospital of ShenzhenShenzhen 518020Guangdong ProvinceChina Department of Intensive Care Unit Peking University Shenzhen HospitalShenzhen 518000Guangdong ProvinceChina

BACKGROUND Coronavirus disease 2019(COVID-19)severity is classified as asymptomatic,mild,moderate,severe,and *** cases account for a large percentage of cases in the epidemic and typically exhibit a favorable ***,a 49%-67%mortality is noted in critical *** COVID-19-specific drug has been reported to date,and symptomatic and optimal supportive care,including oxygenation,anti-coinfection treatments,and ventilation,represent the mainstay of treatment for this disease,especially in critical *** SUMMARY In the above-mentioned context,we share our experience with the treatment of one critical COVID-19 case and review the relevant *** Timely tracheal intubation,reasonable mechanical ventilation support,appropriate anti-infection treatment,and early anticoagulation and immunity support are key factors in the successful treatment of this case.

关键词： COVID-19 Critical case Supportive treatment Mechanical ventilation support Case report Literature review

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不同绣球品种耐寒性评价及主要指标筛选

植物资源与环境学报 2024年第2期33卷 41-49页

作者：陈慧杰严子桢齐香玉陈双双冯景金玉妍苗艳华邓衍明江苏省农业科学院休闲农业研究所江苏省高效园艺作物遗传改良重点实验室江苏南京210014 淮阴工学院生命科学与食品工程学院江苏淮安223001

为了明确绣球〔Hydrangea macrophylla(Thunb.)Ser.〕品种的耐寒性及筛选耐寒性评价主要指标,对40个绣球品种的低温半致死温度(LT_(50))进行比较和耐寒性分级,在此基础上,对5℃、0℃、-5℃、-10℃、-15℃、-20℃下耐寒品种‘小町’(‘Ko... 详细信息

为了明确绣球〔Hydrangea macrophylla(Thunb.)Ser.〕品种的耐寒性及筛选耐寒性评价主要指标,对40个绣球品种的低温半致死温度(LT_(50))进行比较和耐寒性分级,在此基础上,对5℃、0℃、-5℃、-10℃、-15℃、-20℃下耐寒品种‘小町’(‘Komachi’)、‘佳澄’(‘Kasumi’)、‘无尽夏’(‘Endless Summer’)和不耐寒品种‘甜蜜幻想’(‘Sweet Fantasy’)、‘灵感’(‘Inspiration’)、‘你我的情感’(‘You and Me Feelings’)叶的抗氧化酶活性及丙二醛(MDA)和渗透调节物质含量进行比较,并对这些耐寒指标进行相关性分析和主成分分析。结果表明:供试绣球品种LT 50的波动较大,变化范围为-36.68℃~-1.87℃,其中,‘小町’的LT_(50)最低,‘佳澄’、‘平瓣’(‘Flat’)、‘蒂亚娜’(‘Tijana’)、‘塞尔玛’(‘Selma’)、‘含羞叶’(‘Elbtal’)、‘花手鞠’(‘Stockings’)、‘蓝色多瑙河’(‘Blue Danube’)和‘无尽夏’的LT_(50)均低于-20℃。40个绣球品种的耐寒性被分成不耐寒、较耐寒、耐寒和强耐寒4个等级,分别包含13、18、8和1个品种。6个代表品种的过氧化氢酶(CAT)、多酚氧化酶(PPO)和超氧化物歧化酶活性及MDA、脯氨酸(Pro)、可溶性蛋白质(SP)和可溶性糖含量随温度降低基本呈先升高后降低的变化趋势。相关性分析结果表明PPO活性和Pro含量与LT_(50)呈极显著(P<0.01)负相关。主成分分析结果表明:前4个主成分的累计贡献率为81.212%,说明这4个主成分基本能够反映绣球品种的耐寒性;PPO活性、CAT活性、Pro含量和SP含量的负荷量绝对值分别在第1、第2、第3和第4主成分中最高。研究结果显示:供试绣球品种间的耐寒性差异较大,‘小町’等9个品种的耐寒性较强,能够在冬季温度偏低地区露天栽培,并可作为绣球耐寒品种选育的亲本。PPO活性、CAT活性、Pro含量和SP含量为绣球耐寒性评价的主要指标,尤其是PPO活性和Pro含量。

关键词：绣球耐寒性低温半致死温度(LT_(50)) 相关性分析主成分分析

Relative importance of spatial processes and environmental factors in shaping alpine meadow communities

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Journal of Plant Ecology 2011年第4期4卷 249-258页

作者： qi Li Xue Yang Janne Soininen Cheng-jin Chu Jie-qi Zhang Kai-Liang Yu Gang Wang MOE Key Laboratory of Arid and Grassland Ecology Lanzhou UniversityLanzhou 730000China Department of Environmental Sciences University of HelsinkiHelsinkiPO Box 65FI 00014Finland

Spatial processes and environmental control are the two distinct,yet not mutually exclusive forces of community structuring,but the relative importance of these factors is controversial due to the speciesspecific dispersal ability,sensitivity towards environmental variables,organism’s abundance and the effect of spatial *** the present paper,we explored spatial versus environmental control in shaping community composition(i.e.b-diversity)and species turnover(*** of b-diversity)at an alpine meadow along a slope aspect gradient on the qinghai–Tibetan Plateau at different spatial scales of sampling(quadrats and plots),by taking account of seed dispersal mode and *** We examined the relative importance of spatial processes and environmental factors using all species and four additional subsets of selected ***,we attempted to explore the effect of scale(quadrat refers to scale of;0.3 m and plot of;8 m)on their counter *** data were analyzed both by variation partitioning and multiple regressions on distance *** spatial structure was modelled using Moran’s eigenvector maps(MEM).Important Findings Both spatial processes and environmental factors were important determinants of the community composition and species *** community composition in the alpine meadow was controlled by spatially structured environment(17.6%),space independent of environment(18.0%)and a negligible effect of environment independent of space(4.4%)at the scale of *** three components contributed 21.8,9.9 and 13.9%,respectively,at the scale of *** balance between the forces at different spatial scales drove community structures along the slope aspect *** importance of environmental factors on b-diversity at alpine meadow increased with scale while that of spatial processes decreased or kept steady,depending on dispersal mode and abundance of species comprising the *** the‘pure’effect of spatial processes on

关键词： alpine meadow dispersal environmental factor slope aspect spatial process spatial scale

ASYMPTOTIC SOLUTIONS OF BOUNDARY VALUE PROBLEMS FOR THIRD-ORDER ORDINARY DIFFERENTIAL EQUATIONS WITH TURNING POINTS

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Applied Mathematics and Mechanics(English Edition) 2001年第4期22卷 394-403页

作者： JIANG Fu-ru(江福汝) jin qi-nian(金其年) Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072 P R China Department of Mathematics Nanjing University Nanjing 210000 P R China

Boundary value problem; for third-order ordinary differential equations with turning points are studied as follows : epsilon gamma ' ' + f(x ; epsilon) gamma ' + g(x ; epsilon) gamma ' +h(x ; epsilon) gamma = 0 (- a < x < b, 0 epsilon 1), where f(x ; 0) has several multiple zero points in ( - n, b). the necessary conditions for exhibiting resonance is given, and the uniformly valid asymptotic solutions and the estimations of remainder terms are obtained.

关键词： boundary value problems ordinary differential equations turning points asymptotic solutions

Recent advances in anode materials for potassium-ion batteries:A review

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Nano Research 2021年第12期14卷 4442-4470页

作者： Lianbo Ma Yaohui Lv Junxiong Wu Chuan Xia qi Kang Yizhou Zhang Hanfeng Liang Zhong jin School of Materials Science and Engineering Anhui University of TechnologyMaanshan243002China Key Laboratory of Mesoscopic Chemistry of Ministry of Education(MOE) Jiangsu Key Laboratory of Advanced Organic MaterialsState Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China Shenzhen Research Institute of Nanjing University Shenzhen518063China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu610054China Department of Polymer Science and Engineering Shanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai200240China Institute of Advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials SciencesNanjing University of Information Science&TechnologyNanjing210044China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen361005China

Potassium-ion batteries(PIBs)are appealing alternatives to conventional lithium-ion batteries(LIBs)because of their wide potential window,fast ionic conductivity in the electrolyte,and reduced ***,PIBs suffer from sluggish K+reaction kinetics in electrode materials,large volume expansion of electroactive materials,and the unstable solid electrolyte *** strategies,especially in terms of electrode design,have been proposed to address these *** this review,the recent progress on advanced anode materials of PIBs is systematically discussed,ranging from the design principles,and nanoscale fabrication and engineering to the structure-performance ***,the remaining limitations,potential solutions,and possible research directions for the development of PIBs towards practical applications are *** review will provide new insights into the lab development and real-world applications of PIBs.

关键词： potassium-ion batteries anode materials nanoscale engineering electrode design

Elasto-plastic Analysis of Circular Tunnels in Jointed Rock Masses Satisfy the Hoek-Brown Failure Criterion

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Journal of China University of Mining and Technology 2007年第3期17卷 393-398页

作者： SUN jin-shan LU Wen-bo ZHU qi-hu CHEN Ming State Key Laboratory of Water Resource and Hydropower Engineering Science Wuhan University Wuhan Hubei 430072 China

The relationship between the Hoek-Brown parameters and the mechanical response of circular tunnels is il-lustrated. Closed-form and approximate solutions are given for the extent of the plastic zone and the stress and dis-placement fields under axisymmetrical and asymmetric stress conditions. For the same rock masses and under axisym-metrical stress conditions,the radius of the plastic zone in terms of Hoek-Brown criterion is generally an approximation of the radius in terms of the Mohr-Coulomb criterion. The radius in terms of the Hoek-Brown criterion is larger under low stress conditions. For poor quality rock masses (GSI<25),measures (such as grouting,setting rock bolts,etc.) that improve the GSI of rock masses are effective in improving the stability of tunnels. It is not advisable to improve the sta-bility of the tunnels by providing a small support resistance p through shotcrete,except for very poor quality jointed rock masses. Without reference to the quality of the rock mass,the disturbance factor D should not less than 0.5. Meas-ures which disturb rock masses during tunnel construction should be taken carefully when the tunnel depth increases.

关键词： jointed rock masses circular tunnel general Hoek-Brown failure criterion elasto-plastic analysis con-struction measures