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Acta Mechanica Sinica 2015年第5期31卷 647-652页

作者： Ling-Cheng kong Yuan-Tai Hu Department of Mechanics Huazhong University of Science and Technology

With introduction of the first-order strain-gradient of surface micro-beams into the energy density function,we developed a two-dimensional dynamic model for a compound quartz crystal resonator（QCR） system,consisting of a QCR and surface micro-beam *** frequency shift that was induced by micro-beams with consideration of strain-gradients is discussed in detail and some useful results are obtained,which have important significance in resonator design and applications.

关键词： Micro-beams Strain-gradient Quartz crystal resonator Frequency shift

Correlation between Polyphenol Contents and Antioxidant Activities in Different Echinacea Purpurea Varieties

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当代医学科学(英文) 2023年第4期43卷 831-837页

作者： Xiao-jing LIN Zheng-shi-yu LAI Qun LUO Mei kong Min-jian LIANG Hong WU Mei BAI Guangdong Technology Research Center for Traditional Chinese Veterinary Medicine and Natural Medicine South China Agricultural UniversityGuangzhou 510642China Qilu Animal Health Products Company Jinan 250033China State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources College of Life SciencesSouth China Agricultural UniversityGuangzhou 510642China

Objective:Polyphenols are complex compounds containing multiple phenolic hydroxyl *** are widely distributed in plants and have antioxidant *** the antioxidant activities of the cultivated varieties of Echinacea are similar to or better than those of the wild ones and the relationship between the accumulation of polyphenols and their antioxidant activities are still not ***:Folin-Ciocalteu method,high performance liquid chromatography(HPLC),2,2-diphenyl-1-picrylhydrazyl(DPPH)radical scavenging assay,ferric ion reducing antioxidant power(FRAP)assay,2,2'-azino-bis(3-ethylbenzothiazoline-6)-sulfonic acid(ABTS)radical scavenging assay,and Fe^(2+)chelating ability assay were used,respectively,to detect the total polyphenols and 5 kinds of caffeic acid derivatives(chicoric acid,caffeic acid,caftaric acid,chlorogenic acid,and 1,5-dicaffeoylquinic acid)in the roots,stems,leaves,and flowers,and the antioxidant activities of 3 varieties of Echinacea:*** L.,cultivar ***'Aloha',and ***'White Swan'.Results:*** *** the highest contents of total polyphenols,5 caffeic acid derivatives and antioxidant activities,followed by ***'White Swan'and ***'Aloha',***'White Swan'had the strongest ability to remove the DPPH,ABTS·^(+)and free radicals,and to chelate Fe^(2+);*** *** the strongest ability to reduce *** correlation analyses revealed that the contents of total polyphenols and caffeic acid derivatives of *** *** ***'White Swan'were correlated with their antioxidant ***:*** *** the most appropriate material for the development of medicinal ***'White Swan'could be used as a substitute for *** *** terms of its antioxidant activity.

关键词： antioxidant activity caffeic acid derivatives Echinacea purpurea medicinal plants total polyphenol

银杏叶基锂离子电池炭负极材料制备及电化学性能研究

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辽宁化工 2024年第7期53卷 990-992,996页

作者：刘大龙安玉良孙超群孔汉文谢驰袁霞沈阳理工大学材料科学与工程学院辽宁沈阳110159

以银杏叶为基质制备锂离子电池负极材料,采用活化剂FeCl_(3)对银杏叶(GL)浸渍,通过不同温度进行碳化处理,并且对于银杏叶基负极材料的电化学性能进行探究。通过FeCl_(3)活化可以改善银杏叶生物质炭的孔结构,实验考察不同活化温度考察对... 详细信息

以银杏叶为基质制备锂离子电池负极材料,采用活化剂FeCl_(3)对银杏叶(GL)浸渍,通过不同温度进行碳化处理,并且对于银杏叶基负极材料的电化学性能进行探究。通过FeCl_(3)活化可以改善银杏叶生物质炭的孔结构,实验考察不同活化温度考察对产物结构和性能的影响,得到最优活化温度为600℃。制备出的产品在电流密度0.1A·g^(-1),电压为0.01~3.0V条件下首次放电比容量和首次库伦效率分别为:941 mAh·g^(-1),61.63%。30圈充放电循环后的放电比容量和库伦效率分别为:453.5 mAh·g^(-1),98.75%。

关键词：银杏叶活化负极材料 FeCl_(3)

Time Series Analysis for Vibration-Based Structural Health Monitoring:A Review

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Structural Durability & Health Monitoring 2018年第3期12卷 129-147页

作者： kong Fah Tee School of Engineering University of GreenwichKentUK.

Structural health monitoring(SHM)is a vast,interdisciplinary research field whose literature spans several decades with focusing on condition assessment of different types of structures including aerospace,mechanical and civil *** need for quantitative global damage detection methods that can be applied to complex structures has led to vibration-based *** time series methods for SHM form an important and rapidly evolving category within the broader vibration-based *** the literature on the structural damage detection,many time series-based methods have been *** a considered time series model approximates the vibration response of a structure and model coefficients or residual error are obtained,any deviations in these coefficients or residual error can be inferred as an indication of a change or damage in the *** on the technique employed,various damage sensitive features have been proposed to capture the *** paper reviews the application of time series analysis for *** different types of time series analysis are described,and the basic principles are explained in ***,the literature is reviewed based on how a damage sensitive feature is *** addition,some investigations that have attempted to modify and/or combine time series analysis with other approaches for better damage identification are presented.

关键词： Time series snalysis structural health monitoring structural damage detection autoregressive model damage sensitive features

带线锚钉穿骨张力带与高强线环扎双重固定治疗髌骨骨折的疗效观察

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中国骨与关节杂志 2024年第2期13卷 118-122页

作者：孔嘉琛柳直王猛姚五平李玉吉甘肃中医药大学兰州730000 甘肃省中医院兰州730000

目的观察带线锚钉穿骨张力带与高强线环扎双重固定治疗髌骨骨折的临床疗效,分析该术式对于治疗髌骨骨折的安全性、可行性。方法回顾分析2021年4月1日至2021年12月1日在甘肃省中医院门、急诊确诊为髌骨骨折并使用带线锚钉穿骨张力带与高... 详细信息

目的观察带线锚钉穿骨张力带与高强线环扎双重固定治疗髌骨骨折的临床疗效,分析该术式对于治疗髌骨骨折的安全性、可行性。方法回顾分析2021年4月1日至2021年12月1日在甘肃省中医院门、急诊确诊为髌骨骨折并使用带线锚钉穿骨张力带与高强线环扎双重固定治疗的20例患者的资料。其中男12例,女8例,平均年龄(46.7±11.8)岁,均为新鲜的单纯髌骨骨折且无其它部位复合伤及内科严重疾患,于我院行带线锚钉穿骨张力带与高强线环扎双重固定治疗。记录患者术后不良反应发生情况,于术后、术后12周常规拍摄膝关节正侧位X线片、观察记录术后骨折愈合时间、术后有无并发症及是否需要二次手术。并在术后12周对患者进行膝关节Lysholm评分及美国特种外科医院膝关节评分(Hospital For Special Surgery Knee Score,HSS)。结果所有患者术后无并发症发生,骨折愈合良好,内固定无松动或再骨折。患者术后12周Lysholm评分优12例,良8例,平均(94.95±3.87)分;HSS评分优19例,良1例,平均(90.80±3.87)分。结论带线锚钉穿骨张力带与高强线环扎双重固定治疗髌骨骨折可获得较好的疗效,能够准确复位骨折端,促进骨折愈合,尤其是粉碎性骨折块,减轻术后疼痛,无需二次手术取出内植物。

关键词：骨折髌骨骨折固定术内治疗结果

凡纳对虾高低繁殖力群体卵巢组织学观察及相关候选基因的表达分析

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渔业科学进展 2024年第5期45卷 183-194页

作者：张建春孔杰曹家旺谭建代平孟宪红罗坤傅强陈宝龙刘东亚邢群隋娟栾生中国水产科学研究院黄海水产研究所、农业农村部海洋渔业与可持续发展重点实验室、青岛海洋科技中心海洋渔业科学与食物产出过程功能实验室山东青岛266071 上海海洋大学水产与生命学院上海201306 邦普种业科技有限公司山东潍坊261312

在生产中,凡纳对虾(Penaeus vannamei)雌虾的繁殖性能表现出巨大差异。本研究以一个生产周期中雌虾产卵频次为繁殖力指标性状,以高繁殖力和低繁殖力雌虾为研究对象,对雌虾不同卵巢发育阶段(增殖期、小生长期、大生长期和成熟期)进行组... 详细信息

在生产中,凡纳对虾(Penaeus vannamei)雌虾的繁殖性能表现出巨大差异。本研究以一个生产周期中雌虾产卵频次为繁殖力指标性状,以高繁殖力和低繁殖力雌虾为研究对象,对雌虾不同卵巢发育阶段(增殖期、小生长期、大生长期和成熟期)进行组织学观察。针对在前期选择清除分析中筛选到的繁殖候选基因TRX2、PARD3、PLCβ4和RERE,在高、低繁殖力雌虾不同卵巢发育阶段,采用实时荧光定量PCR方法,首次分析比较这些基因在卵巢、眼柄组织中的表达规律。组织观察结果显示,低繁殖力雌虾卵巢在整个生产周期中无法发育至成熟期,高繁殖力雌虾卵巢在卵黄颗粒的形成和积累、皮质棒形成等关键过程的速度要快于低繁殖力雌虾。基因表达检测结果显示,在卵巢小生长期和大生长期,TRX2、PLCβ4和RERE基因在高繁殖力组卵巢的表达量均显著高于低繁殖力组卵巢(P<0.05),4个基因在高繁殖力组成熟期卵巢中均维持较高的表达水平;在不同时期的眼柄组织中,低繁殖力组中TRX2、PARD3、PLCβ4和RERE基因的表达量均高于高繁殖力组。研究表明,上述4种基因可能在凡纳对虾卵巢发育过程中发挥重要作用。以上结果为深入研究凡纳对虾雌虾繁殖力产生差异的分子机制以及分子辅助育种提供了重要参考。

关键词：凡纳对虾繁殖卵巢组织学基因表达模式

Analysis of relative error in detection caused by signal-induced noise in Na lidar system

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Science China Earth Sciences 2018年第1期61卷 109-118页

作者： ZHANG YunPeng YI Fan kong Wei School of Electronic Information Wuhan University

Signal-induced noise(SIN) in a photomultiplier tube(PMT) introduces bias into the Na density results that are retrieved from the backscattered signals of Na resonance fluorescence lidar systems. The response characteristics of a PMT when stimulated by a series of light pulses with a fixed width of 1 μs are therefore used to develop a precise SIN model to estimate the relative error caused by SIN. Unless the strong signals that are returned from the lower atmosphere are excluded, the measured density results are always smaller than the actual values, and the resulting relative error may be 50% or more. Three potential solutions to reduce the SIN were quantified for comparison, including use of a chopper system, use of a gated circuit, and separation of the laser beam and the telescope receiver. When optimized parameters are used for these technologies, the relative error can then be reduced to less than 2%.

关键词：激光雷达导致信号的噪音光电倍增管试管

Evaluation of the effect of wall boundary conditions on numerical simulations of circulating fluidized beds

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Particuology 2014年第2期12卷 114-123页

作者： Lei kong Chao Zhang Jesse Zhu Department of Mechanical and Materials Engineering The University of Western OntarioLondonOntarioN6A 5B9Canada Department of Chemical and Biochemical Engineering The University of Western OntarioLondonOntarioN6A 5B9Canada

A computational fluid dynamics （CFD） modeling of the gas-solids two-phase flow in a circulating fluidized bed （CFB） riser is carried out. The Eularian-Eularian method with the kinetic theory of granular flow is used to solve the gas-solids two-phase flow in the CFB riser. The wall boundary condition of the riser is defined based on the Johnson and Jackson wall boundary theory （Johnson ＆ Jackson, 1987） with specularity coefficient and particle-wall restitution *** numerical results show that these two coefficients in the wall boundary condition play a major role in the predicted solids lateral velocity, which affects the solid particle distribution in the CFB riser. And the effect of each of the two coefficients on the solids distribution also depends on the other one. The generality of the CFD model is further validated under different operatin~ conditions of the CFB riser.

关键词： CFD Circulating fluidized bed Gas-solids two-phase flowWall boundary conditionSpecularity coefficientParticle-wall restitution coefficient

Engineering Geology of Limestone in Malaysia

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Acta Geologica Sinica(English Edition) 2001年第3期75卷 316-324页

作者： TAN Boon-kong Geology Programme Faculty of Science & Technology Universiti Kebangsaan Malaysia Bangi Malaysia

This paper provides an overview of the engineering geology of limestone. Limestone is of rather wide occurrence in Malaysia. It is interesting in view of the unique landforms and karstic features that are encountered in limestone terrains, e.g. steep, subvertical limestone cliffs rising abruptly and majestically above the ground surface and highly variable and pinnacled subterranean limestone bedrock. The karstic features and associated engineering geological problems of both the limestone hills and the bedrock are discussed in the paper. Rockfalls, sinkholes, cavities, etc. are some of the common engineering geological problems associated with limestone terrains. Some local case studies are provided as illustrations. Finally the rock mechanical properties of limestone is discussed at the end of the paper.

关键词： engineering geology limestone Malaysia

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亚洲象保护区外的栖息地偏好空间模拟评估

林业建设 2024年第2期42卷 7-14页

作者：文芒才陈颖宗春淼丁念繁陶庆西双版纳州亚洲象保护管理中心云南景洪666100 云南西双版纳国家级自然保护区科学研究所云南景洪666100 北京林业大学生态与自然保护学院北京100083 香港大学生物科学学院中国香港999077 云南西双版纳国家级自然保护区管护局云南景洪666100

栖息地丧失和破碎化已成为野生动物和生物多样性保护面临的最大威胁之一。本研究基于3年(2019—2021)无人机调查收集到的亚洲象分布数据,构建了多变量多尺度物种分布模型,评估了地形地貌、土地利用、线性基础设施和居民点等环境变量对... 详细信息

栖息地丧失和破碎化已成为野生动物和生物多样性保护面临的最大威胁之一。本研究基于3年(2019—2021)无人机调查收集到的亚洲象分布数据,构建了多变量多尺度物种分布模型,评估了地形地貌、土地利用、线性基础设施和居民点等环境变量对亚洲象分布的影响。在研究期间无人机共监测到10719个亚洲象分布位点,其中旱季共收集到5088个分布点,雨季5630个分布点。研究结果显示,海拔、橡胶林延展度、农田延展度、森林延展度、景观延展度、荒地破碎度、农田破碎度、密林破碎度和道路密度,共9个变量对亚洲象分布的影响比较大。2021年,西双版纳州面积的27%,约5181 km^(2)为亚洲象适宜栖息地,可容纳约347(187—554)头亚洲象;适宜栖息地主要分布在与普洱临界区域的西双版纳州北部,以及呈斑块状分布在西双版纳州南部的尚勇保护区的西部、东北部和勐腊保护区周边,但北部适宜栖息地内的农田被亚洲象觅食或踩踏的概率高,南部适宜栖息地被橡胶林蚕食的风险高,处于中老缅边境的布龙州级保护区和易武州级保护区分布有少量的亚洲象适宜栖息地。研究结果将为云南亚洲象国家公园的规划和亚洲象种群管理提供有价值的科技支撑。

关键词：亚洲象栖息地破碎化人象冲突无人机