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Evaluation of thermotherapy against Huanglongbing (citrus greening) in the greenhouse

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Journal of Integrative Agriculture 2016年第1期15卷 111-119页

作者： fan guo-cheng XIA Yu-lu LIN Xiong-jie HU Han-qing WANG Xian-da RUAN Chuan-qing LU Lian-ming LIU Bo Fruit Research Institute Fujian Academy of Agricultural Sciences Fuzhou 350013 P.R. China National Science Foundation Center for Integrated Pest Management North Carolina State University Raleigh NC 27606 USA Agricultural Bio-Resources Research Institute Fujian Academy of Agricultural Sciences Fuzhou 350003 P.R. China Zhejiang Citrus Research Institute Taizhou 318020 P.R. China

Huanglongbing （HLB, or citrus greening） is the most destructive disease of citrus, which is associated with Candidatus Liberibacter asiaticus （Las）. Few management options are available, aside from preventive measures such as removing infected plants, planting disease-free seedlings, and managing the insect vector. In this study, we assessed the efficacy of thermotherapy against HLB under controlled greenhouse conditions. A total of 60 two-year-old, graft-infected Citrus reticulata Blanco plants were used. The plants were randomly divided into three groups （45℃, 48℃, and untreated control）, with five plants/replicate （rep） and four reps/treatment. The treated plants were placed in phytotrons for a 4-h treatment session, repeated once per week for three consecutive weeks. Disease remission was observed eight weeks post-treatment. Real-time PCR assays revealed that Las titers in HLB-affected seedlings were significantly reduced in both 45 and 48℃ treatments four weeks after treatment, with the exception of eight plants. In contrast, Las titers in the untreated control plants increased significantly during the same period, with a maximum increase of 28-fold. Except for seven plants, Las titers in the new flushes of treated plants decreased more than 90% eight weeks after treatment. Las titers in mature leaves of treated plants decreased 56 and 60% in average at 45 and 48℃, respectively, eight weeks after treatment. The HLB symptoms and Las titer of seedings were markedly alleviated eight weeks after treatment in both 45 and 48℃ treatments. Our results laid a good foundation for the further development of citrus free-disease seedling cultivation and Huanglongbing control in the field. The whole plants were replaced for scion or branch in previous as the research object in this study, and the expression of Huanglongbing symptoms combined with real-time polymerase chain reaction （PCR） were used to evaluate the effect of heat treatment in the greenhouse.

关键词： Candidatus Liberibacter asiaticus Citrus reticulata thermotherapy bacterial titer

Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： fan YANG Zhaoyang MA Xingming guo Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University Shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

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度尾文旦柚辨形疏果最佳FSI阈值研究

福建农业学报 2020年第3期35卷 280-285页

作者：王贤达范国成李健福建省农业科学院果树研究所福建福州350013

【目的】根据裂果率(FCR)与果形指数(FSI)负相关原理,研究FSI辨形疏果的最佳FSI阈值。【方法】由2016-2018年于仙游县度尾文旦柚主产区采集n=8660的果实裂宽(FCW)与FSI数据,对果实FSI及其裂顶与否的分布进行分析,研究FSI辨形疏果的报酬... 详细信息

【目的】根据裂果率(FCR)与果形指数(FSI)负相关原理,研究FSI辨形疏果的最佳FSI阈值。【方法】由2016-2018年于仙游县度尾文旦柚主产区采集n=8660的果实裂宽(FCW)与FSI数据,对果实FSI及其裂顶与否的分布进行分析,研究FSI辨形疏果的报酬与降低裂果率代价。【结果】FSI=0.90是疏果报酬盈亏拐点,疏果FSI阈值的上限为0.90。经迭代回归模拟Logistic累积曲线,FSI≤0.83区间疏除裂果效率相对较高;当FSI≤0.80时,疏果量约20%,疏果报酬>2.0;若FSI>0.80时,疏果量将陡增,疏果报酬<2.0,反之FSI<0.80裂果疏除效率降低。据试验总体与3年裂果率Logistic累积曲线变率的峰值评估,FSI≤0.80疏果阈值可靠安全,无过度误导疏果可能。【结论】为降低疏果对产量的影响,提高疏果FSI阈值的可靠性,本文推荐最佳疏果阈值为FSI≤0.80,丰产年份可考虑提升疏果阈值为FSI≤0.83。

关键词：度尾文旦柚果实裂顶果形指数辨形疏果阈值

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散射线光源作参光的投影彩虹全息术

四川大学学报（自然科学版） 1992年第1期29卷 66-71页

作者：江朝川范诚郭履容四川大学信息光学研究所

给出了一种用散射线光源作参光记录投影彩虹全息图的方法.实现了狭缝在景物后面的大量展宽,可不通过狭缝实象观察到全景虚象.

关键词：全息术散射线光源彩虹全息术

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叶梁热压面温度均匀性分析及仿真模拟

机械设计与制造 2009年第1期 15-17页

作者：岳鹏高殿斌范国成杨涛天津工业大学机械电子学院天津300160

利用有限元软件ANSYS模拟仿真叶梁热压成型过程中热压面温度变化,分析热压面温度不均匀的原因。通过实验得到的预测性数据,为叶梁热压设备加热机构的分布改进提供了一些必要的参考数据和设计依据。实验得到的叶梁成型温度均匀一致,总体... 详细信息

利用有限元软件ANSYS模拟仿真叶梁热压成型过程中热压面温度变化,分析热压面温度不均匀的原因。通过实验得到的预测性数据,为叶梁热压设备加热机构的分布改进提供了一些必要的参考数据和设计依据。实验得到的叶梁成型温度均匀一致,总体误差在±0.5℃,最高温度和最低温度之差小于0.2%。

关键词：热压面温度仿真模拟叶梁

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大梁带铺放设备概念设计

机械设计与制造 2009年第1期 7-9页

作者：范国成高殿斌杨涛岳鹏天津工业大学机械电子学院天津300160

论述了飞机上大梁带铺放机构的工作原理及设计方法。采用集成化设计概念,将铺放机的放料、除膜、张力控制、施压、剪切等必要装置集中组成铺放头机构;同时吸收缠绕技术中在线固化的技术,提出了逐层铺放,一步到位的理念,通过840D控制铺... 详细信息

论述了飞机上大梁带铺放机构的工作原理及设计方法。采用集成化设计概念,将铺放机的放料、除膜、张力控制、施压、剪切等必要装置集中组成铺放头机构;同时吸收缠绕技术中在线固化的技术,提出了逐层铺放,一步到位的理念,通过840D控制铺放头按规划的轨迹运动以实现精确铺层,提高产品质量。

关键词：大梁带铺放铺放头 840D 伺服驱动张力

柑橘黄龙病菌核糖体蛋白基因的多态性及系统发育分析

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浙江大学学报（农业与生命科学版） 2011年第2期37卷 125-132页

作者：鹿连明范国成姚锦爱胡秀荣陈国庆浙江省柑橘研究所浙江台州318020 福建省农业科学院果树研究所福建福州350013 福建省农业科学院植物保护研究所福建福州350013

通过PCR扩增6个不同地区柑橘黄龙病（citrus huanglongbing，HLB）病原茵的核糖体蛋白基因，采用4种不同的限制性内切酶对PCR产物进行限制性片段长度多态性（RFLP）分析；并对核糖体蛋白基因克隆和测序后，使用DNAman和NCBI Blast等软... 详细信息

通过PCR扩增6个不同地区柑橘黄龙病（citrus huanglongbing，HLB）病原茵的核糖体蛋白基因，采用4种不同的限制性内切酶对PCR产物进行限制性片段长度多态性（RFLP）分析；并对核糖体蛋白基因克隆和测序后，使用DNAman和NCBI Blast等软件对基因序列进行比对分析，并通过软件Mega4．1构建其系统发育树．结果表明：6个分离物核糖体蛋白基因的RFLP指纹图谱有所差异，表现出一定的多态性；不同分离物核糖体蛋白基因的核酸序列和氨基酸序列均存在差异，但相互之间同源性很高，其中核酸序列与数据库中亚洲种（CandidatusLiberibacterasiaticus）的同源性高达99％～100％，与非洲种（***）的同源性为85％，与美洲种（***）的同源性为77％～80％；系统发育分析显示所有的***亲缘关系极近，归为一个类群，而后与***和***组成韧皮部杆菌属（CandidatusLiberibacter）一个大的类群．

关键词：亚洲种黄龙病菌核糖体蛋白基因多态性系统发育分析

Fluid evolution in the Rushan lode gold deposit of Jiaodong Peninsula,eastern China

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Fluid evolution in the Rushan lode gold deposit of Jiaodong ...

中国科学院地质与地球物理研究所2006学术年会

作者： fang-fang Hu,Hong-Rui fan,Ming-guo Zhai,cheng-Wei Jin Key Laboratery of Mineral Resources,Institute of Geoloogy and Geophysics,Chinese Academy of Sciences, Beijing 100029,China

The Rushan gold deposit in the Jiaodong Peninsula is currently the largest lode gold in *** occurs mainly in pyrite- and polymetallic sulfide-quartz vein/veinlet stockworks. Fluid inclusions in the deposit are divided into three main types,namely CO2-H2O, H2O-CO2±CH4 and aqueous *** data show that the pre-gold fluids were CO2-dominant(XCO2 up to 0.53),and the total homogenization temperatures fall in the range of 298～377℃.These fluids,modified by fluid/wallrock reactions,gradually evolved into fluids with less CO2(XCO2=0.01～0.19) in the main ore-forming stage,and the total homogenization temperatures range from 170～32℃.Hydrogen and oxygen stable isotope data suggest that ore-forming fluids were mixture of magmatic and meteoritic ***-occurrence of gold and sulfides implies that gold was most likely transported in the form of gold-sulfide *** wide distribution of CO2 inclusions mean that the pH variation during gold transportation was controlled by CO2 buffering.

关键词： Fluid inclusion Stable isotope Rushan lode gold deposit Jiaodong Peninsula

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文旦柚品种群果实裂果研究概况

东南园艺 2019年第6期7卷 60-65页

作者：王贤达范国成福建省农业科学院果树研究所福建福州350013

我国柚类主要有三大品种群:沙田柚、文旦柚和种间杂交品种群,其中以文旦柚品种群裂果最严重。裂果是一种生理病害,主要由遗传特性决定,但同时受果皮结构特征、矿质营养、激素和外界环境影响。裂果易腐烂,不易储运,进而降低果实的商品价... 详细信息

我国柚类主要有三大品种群:沙田柚、文旦柚和种间杂交品种群,其中以文旦柚品种群裂果最严重。裂果是一种生理病害,主要由遗传特性决定,但同时受果皮结构特征、矿质营养、激素和外界环境影响。裂果易腐烂,不易储运,进而降低果实的商品价值,产生巨大的经济损失。本文就裂果形态与时期、裂果影响因素和防裂技术措施等3方面进行综述,以期为文旦柚品种群果实裂果研究与栽培提供参考。

关键词：文旦柚裂果水分矿质营养激素