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Picea species from humid continental and temperate marine climates perform better in monsoonal areas of middle latitudes of China

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Journal of Forestry Research 2021年第4期32卷 1395-1408页

作者： Fangqun Ouyang Jianwei ma Junchen Wang Lisheng Kong Hanguo Zhang Mulualem Tigabu junhui Wang State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of State Forestry AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Research Institute of Forestry of Xiaolong Mountain Gansu Provincial Key Laboratory of Secondary Forest CultivationGansuPeople’s Republic of China Beijing Botanical Garden Beijing Floriculture Engineering Technology Research CentreBeijing Laboratory of Urban and Rural Ecological EnvironmentBeijingPeople’s Republic of China Department of Biology Centre for Forest BiologyUniversity of VictoriaVictoriaBCCanada State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China Swedish University of Agricultural Sciences Southern Swedish Forest Research CenterBox 4923053 AlnarpSweden

Picea spp.are a prominent component of the boreal,montane,and sub-alpine forests in the Northern Hemisphere,and have substantial economic importance due to their high quality fibre.However,performance and wood properties of the genus have not been systematically evaluated in China.This study aimed to examine genetic variations in growth traits,phenology,and wood properties of 17 Picea species,(three from North America,two from Europe,and 12 from China),in response to specific climate factors using a randomized complete block design in a monsoonal,middle latitude area of China.Results show that all growth traits and wood properties significantly varied among species(P maller cell wall thicknesses to tracheid radial lumen diameter ratios(WT/R_D1),which is favorable for pulp production.Correlation analysis revealed that height and ring width had significant positive correlations with latitude but strongly negative correlations with longitude.Height was positively correlated with average annual rainfalls,but negative correlations with average yearly sunshine.Due to the increased average annual sunshine at the China test site relative to the seed source,species such as P.abies,P.pungens,P.glauca,and P.omorika from wet,humid areas performed better than native species.Considering similar temperatures,precipitation may be the main factor affecting growth,which is beneficial for predicting the extent of spruce expansion.These results should encour

关键词： Climate Growth performance Genetic variations Picea Wood properties

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跨介质飞行器头部外形优化及入水性能分析

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兵工学报 2022年第10期43卷 2588-2597页

作者：马文朝孟繁敏马诺孟军辉邹汝平北京理工大学宇航学院北京100081 飞行器动力学与控制教育部重点试验室北京100081 中国兵器工业集团公司西安现代控制技术研究所陕西西安710003

跨介质飞行器头部外形是影响跨介质过程中运动学特性的重要因素之一。通过采用常见的双参数立方多项式曲线方程,获取跨介质飞行器头部外形曲线无量纲参数,采用任意拉格朗日-欧拉方法完成不同头部外形跨介质飞行器的流固耦合建模及性能分... 详细信息

跨介质飞行器头部外形是影响跨介质过程中运动学特性的重要因素之一。通过采用常见的双参数立方多项式曲线方程,获取跨介质飞行器头部外形曲线无量纲参数,采用任意拉格朗日-欧拉方法完成不同头部外形跨介质飞行器的流固耦合建模及性能分析,研究不同头部外形入水后末速度与入水过程中所受最大冲击应力。以最大末速度和最小冲击应力为优化目标,在保证有限元仿真精度的同时,通过径向基神经网络提升计算效率,并利用多岛遗传算法对跨介质飞行器头部外形进行多目标优化,以得到最佳的头部外形。研究结果表明,跨介质飞行器最优头部外形相对于基本外形,入水过程速度衰减量与所受冲击应力明显降低,有效地减少入水过程中跨介质飞行器的能量损失,可为跨介质飞行器的头部外形设计提供参考。

关键词：跨介质飞行器流固耦合头部外形优化设计入水性能分析

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Streak camera calibration for bunch length measurement at BEPC II

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Radiation Detection Technology and Methods 2021年第3期5卷 466-473页

作者： Wan Zhang Dechong Zhu Yanfeng Sui Huizhou ma junhui Yue Jianshe Cao Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039China

Purpose Streak camera is an important device for bunch length measurement.The errors introduced by streak camera should be considered in measurement.In order to accurately measure bunch length,some streak camera calibrations are studied at BEPC II.Methods In this context,the point spread function,caused by the optical system,is measured at focus mode with both deflec-tions disabled.In the same conditions,the influence of camera gain on measurement is studied.For the dual sweep mode of streak camera,a calibration method using electrical delays is applied to calibrate the beam size result.Results Firstly,a point spread function calibration 1.78 ps of streak camera optical system is obtained with focus mode.Secondly,studying the effect of camera gain on measurement,an optimal camera gain range from 506 to 662 is selected,in which the bunch length measurement error is within 0.5 ps.Thirdly,a dual sweep calibration factor 1.02 is obtained.Conclusions For BEPCII bunch length,there is a little difference before and after the streak camera calibrations.However,for the accurate measurement of ultra-short bunch length,the calibrations are of great significance.

关键词： Streak camera Point spread function Photon counts Dual sweep mode Bunch length measurement

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微创置管吸引术对老年脑出血患者血清炎性因子水平及神经功能的影响

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临床医学工程 2020年第4期27卷 457-458页

作者：马军辉洛阳市汝阳县人民医院神经外科河南洛阳471200

目的探讨微创置管吸引术对老年脑出血患者血清炎性因子水平及神经功能的影响。方法70例老年脑出血患者随机分为两组各35例,对照组行传统开颅清除术治疗,观察组行微创置管吸引术治疗,比较两组手术前后的炎性因子水平及神经功能。结果术后... 详细信息

目的探讨微创置管吸引术对老年脑出血患者血清炎性因子水平及神经功能的影响。方法70例老年脑出血患者随机分为两组各35例,对照组行传统开颅清除术治疗,观察组行微创置管吸引术治疗,比较两组手术前后的炎性因子水平及神经功能。结果术后,两组的血清IL-6、TNF-α、hs-CRP水平以及NIHSS评分均显著降低,且观察组的上述各指标均显著低于对照组(均P<0.05)。结论微创置管吸引术治疗老年脑出血的效果显著,有利于降低患者的血清炎性因子水平,改善神经功能。

关键词：脑出血微创置管吸引术血清炎性因子神经功能

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新型星形负泊松比抗冲击结构设计与入水冲击

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兵工学报 2024年第5期45卷 1497-1513页

作者：金泽华刘清洋马文朝孟军辉北京理工大学宇航学院北京100081 北京理工大学重庆创新中心重庆401135

针对跨介质飞行器入水过程中受到较大冲击载荷的问题,提出一种基于工程需求的负泊松比抗冲击结构拓扑优化设计方法,通过将弹性模量和泊松比引入拓扑优化设计的目标函数,得到满足抗冲击性能需求的负泊松比星形-四边形蜂窝(Star-quadrangu... 详细信息

针对跨介质飞行器入水过程中受到较大冲击载荷的问题,提出一种基于工程需求的负泊松比抗冲击结构拓扑优化设计方法,通过将弹性模量和泊松比引入拓扑优化设计的目标函数,得到满足抗冲击性能需求的负泊松比星形-四边形蜂窝(Star-quadrangular Honeycomb,SQH)结构。在建立SQH结构理论分析模型的基础上,推导冲击载荷下的平台应力解析公式,并通过数值模拟仿真进行校验。通过与星形-圆环蜂窝(Star-circle Honeycomb,SCH)等多种负泊松比结构的比吸能进行对比,得到SQH结构在低速、中速、高速冲击下的比吸能分别高于SCH结构28.74%、45.2%、7.03%。通过流固耦合仿真分析,对所设计的SQH夹层结构进行入水冲击降载研究,进一步讨论SQH夹层结构主要尺寸参数对入水冲击特性的影响。研究结果表明,在尺寸允许范围内,SQH单元倾角和单元壁厚的增大均使得结构产生的加速度峰值减小,动能转化为结构的变形能也减小,验证了用于工程需求的负泊松比结构拓扑优化设计的有效性。

关键词：跨介质飞行器负泊松比拓扑优化冲击吸能平台应力

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Geochronology and Geochemistry of Late Devonian I- and A-Type Granites from the Xing’an Block,NE China:Implications for Slab Break-off during Subduction of the Hegenshan-Heihe Ocean

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Journal of Earth Science 2022年第1期33卷 150-160页

作者： Zheng Ji Wenchun Ge Hao Yang Yanlong Zhang Yu Dong junhui Bi Xiwen Liu College of Earth Sciences Jilin UniversityChangchun 130061China Tianjin Center China Geological SurveyTianjin 300170China Jilin Provincial Water Resources and Hydropower Consultative Company Changchun 130021China

We present detailed geochronological,geochemical,and zircon Hf isotopic data for Late Paleozoic granitic rocks from Handagai and Zhonghe plutons in the Xing’an Block,NE China,aiming to provide constraints on their origin and tectonic implications.New zircon U-Pb ages indicate they were formed in the Late Devonian(ca.379 ma) immediately after a striking 50 ma magmatic lull(ca.430-380 ma) in the Xing ’ an Block.Petrological and geochemical features suggest that the Handagai monzogranites and Zhonghe alkali-feldspar granites are I- and A-type granites,respectively,although both of them have high-K calc-alkaline features and positive zircon ε_(Hf)(t) values(+3.47 to +10.77).We infer that the Handagai monzogranites were produced by partial melting of juvenile basaltic crustal materials under a pressure of materials at shallower depths(P ≤ 4 kbar).Our results,together with published regional data,indicate their generation involves a subduction-related extensional setting.Slab break-off of the Hegenshan-Heihe oceanic plate may account for the subduction-related extensional setting,as well as the transformation of arc magmatism from the Early-Middle Devonian lull to the Late Devonian-Early Carboniferous flare-up in the Xing’an Block.

关键词： Late Devonian granitoids geochemistry slab break-off Hegenshan-Heihe Ocean Xing’an Block

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Thoughts on Present Situation of Development of Rural Animal Husbandry and Its Relationship with Construction of Ecological Agriculture and Revitalization of Rural Industry

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Asian Agricultural Research 2021年第7期13卷 20-23,31页

作者： Dejun TAN Guogui WANG Yunfen ZHU Xiaofei CHEN Jin ma Rong LI junhui XIE Enshi Academy of Agricultural Sciences Enshi 445000 China

After several rounds of phased ups and downs of development,rural animal husbandry finally presents a shrinking and depressed development situation under the comprehensive action of the failure of transformation and upgrading and the increasing production costs and breeding risks.Actively exploring and guiding the healthy and sound development of rural animal husbandry is not only an important measure to promote the construction of ecological agriculture,but also the main starting point to realize the revitalization of rural industry.This paper analyzes the present situation of the development of rural animal husbandry in recent years,the influence of animal husbandry on the construction of ecological agriculture and the revitalization of rural industry,and puts forward the corresponding measures,in order to promote the steady and efficient development of animal husbandry in the grand strategy of revitalizing rural industry.

关键词： Present situation of the development of rural animal husbandry Construction of ecological agriculture Revitalization of rural industry

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Polymer Electron Acceptors Based on Fluorinated Isoindigo Unit for Polymer Solar Cells

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Chinese Journal of Chemistry 2018年第5期36卷 411-416页

作者： junhui Miao Hall Xu Bin Meng Jun Liu Lixiang Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Chang- chun Jijin 130022 China University of Science and Technology of China Hefei Anhui 230026 China Center for Advanced Optoelectronic Functional materials Research Northeast Normal University Changchun Jilin 130024 China

Most of efficient polymer electron acceptors for polymer solar cells （PSCs） are based on naphthalene diimide or perylene diimide as the electron deficient building block. In this paper, for the first time, we report polymer electron acceptors based on fluorinated isoindigo IF-lID） as the electron deficient building block. We synthesized two polymer electron acceptors consisting of alternating F-lID unit and thiophene/selenophen unit, They show low-lying LUMo/HOMO energy levels of-3.69/-5.69 eV, high electron mobilities of 1.31 ×10-5 cm2.V-1s-1 and broad absorption spectra with the optical bandgap of 1.61 eV. PSC devices using the two F-liD-based polymers as polymer electron acceptors show encouraging power conversion efficiencies （PCEs） of up to 1.50% with an open-circuit voltage （Voc） of 0.97V, a short-circuit current density （Jsc） of 2.91 ma.cm2, and a fill factor （FF） of 53.2%. This work suggests a new kind of polymer electron acceptors based on F-IID unit.

关键词： polymer solar cells polymer electron acceptor fluorinated isoindigo n-type conjugated polymer

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Final-stage Southward Subduction of the Eastern Paleo-Asian Ocean:Evidence from the Middle Permian mafic Intrusions in the Northern margin of the North China Craton

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 81-99页

作者： JING Yan GE Wenchun DONG Yu YANG Hao JI Zheng BI junhui ZHOU Hongying XING Dehe College of Earth Sciences Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and Resources of ChinaChangchun 130026China Tianjin Center China Geological SurveyTianjin 300170China Shenyang Center China Geological SurveyShenyang 110034China

The northern margin of the North China Craton(NCC)contains widespread Permian magmatic rocks,but the origin of these rocks remains controversial.This uncertainty hampers us from better understanding of tectonic framework and evolution of the eastern Paleo-Asian Ocean,particularly with respect to its final-stage subduction and closure time.To address these questions,this study presents petrological,zircon U-Pb geochronological,whole-rock geochemical and in situ zircon Hf isotopic data for these Permian mafic intrusions in the northern margin of the NCC.Precise zircon U-Pb dating results indicate that these mafic intrusions were emplaced in the Middle Permian(ca.260 ma).Geochemically,the studied mafic intrusions have high MgO and transition metals element contents,with high Mg^(#) values,indicating a mantle origin.These mafic intrusions are characterized by enrichments in large ion lithophile elements(LILEs;e.g.,Rb,Ba,and K)and light rare earth elements(LREEs),and depletions in high field strength elements(HFSEs;e.g.,Nb,Ta,and Ti)and heavy rare earth elements(HREEs),indicating that they were formed in a subduction-related setting.These geochemical features,together with zircon ε_(Hf)(t)values(-1.1 to+11.2),indicate that their parental magmas were derived from partial melting of heterogeneous mantle wedge metasomatized by subduction-related fluids,with the contributions of slab sediments.The studied mafic intrusions also show wide range of major and trace elements contents,and variable Mg^(#) values,Eu and Sr anomalies,suggesting that their parental magmas had undergone variable degrees of fractional crystallization.Together with the E-W trending Permian continental arc along the northern margin of the NCC,we confirm that the generation of the Middle Permian mafic intrusions was related to southward subduction of the Paleo-Asian oceanic lithosphere beneath the NCC and the Paleo-Asian Ocean had not closed prior to the Middle Permian.

关键词： Middle Permian mafic intrusions subduction metasomatism northern margin of the North China Craton Paleo-Asian Ocean

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时滞效应对弹性地基上梁主共振响应影响分析

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力学季刊 2022年第2期43卷 366-371页

作者：童俊辉彭剑孙洪鑫马建军湖南科技大学土木工程学院湖南湘潭411201 河南科技大学土木工程学院河南洛阳471023

本文研究了弹性地基上梁主共振响应的时滞效应.基于Hamilton原理,建立了时滞影响下弹性地基上梁的非线性运动微分方程,采用多尺度法,求得了时滞效应下主共振响应调制方程以及稳定性条件.通过数值算例,分析了时滞和调谐参数影响下主共振... 详细信息

本文研究了弹性地基上梁主共振响应的时滞效应.基于Hamilton原理,建立了时滞影响下弹性地基上梁的非线性运动微分方程,采用多尺度法,求得了时滞效应下主共振响应调制方程以及稳定性条件.通过数值算例,分析了时滞和调谐参数影响下主共振响应的峰值及幅频响应特性.结果表明,地基反力中的时滞效应对主共振响应影响较大,会导致共振域偏移,在一定区间内,响应幅值随时滞变化先减小再增大,呈现出周期性,并导致幅频曲线弯曲程度增大.

关键词：弹性地基梁主共振时滞稳定性

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