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Journal of Materials Science & Technology 2021年第8期67卷 95-104页

作者： Yuting Wu Chong Li Xingchuan Xia Hongyan Liang qiqi qi Yongchang Liu State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science&EngineeringTianjin UniversityTianjin300354China School of Material Science and Engineering Hebei University of TechnologyTianjin300130China

Recently,theγ’-strengthened superalloys are of great interests in high temperature applications due to their excellent high temperature strength which is derived from theγ’strengthening *** theseγ’-strengthened superalloys,the changes in morphology,size and distribution ofγ’precipitates due to coarsening during thermal exposure have a significant impact on the properties of *** article briefly summarizes the recent advances on the coarsening behavior of gamma prime precipitates in the recently-developedγ’-strengthened superalloys and its effects on the hot deformation behavior of superalloys,drawing specific examples on Allvac^(■)718 Plus TM and Ni3 Al-based intermetallic *** is found that the particle size plays an important role in morphological evolution ofγ’*** instance,the morphology ofγ’precipitates evolves from cuboidal to strip-like or other complex structures in Ni3 Al-based intermetallic alloys,while theγ’precipitates in Allvac^(■)718 Plus alloy always present nearspherical morphology due to the relatively small initial particle *** Lifshitz-Slyozof-Wagner(LSW)theory and its modifications,as well as Trans-Interface Diffusion Controlled(TIDC)theory have been applied to describing the coarsening kinetics ofγ’***,the hot deformation behavior ofγ’-strengthened superalloy is found to be greatly influenced by the coarsening ofγ’precipitates.

关键词： γ’-strengthened superalloy Microstructure Coarsening Hot deformation

人口老龄化对农户技术采纳行为的影响 ——以我国荔枝产业为例

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人口老龄化对农户技术采纳行为的影响 ...

作者： qi qiqi 华南农业大学

学位级别：硕士

以中青年人为主的农村劳动力不断涌向城市的现象,使得农村现有劳动力年龄结构发生了巨大改变,农村人口老龄化现象严重。农业劳动力老龄化是我国经济转型过程中必须经历的阶段。我国要解决老龄化对农业生产产生的消极影响,确保农业现代... 详细信息

以中青年人为主的农村劳动力不断涌向城市的现象,使得农村现有劳动力年龄结构发生了巨大改变,农村人口老龄化现象严重。农业劳动力老龄化是我国经济转型过程中必须经历的阶段。我国要解决老龄化对农业生产产生的消极影响,确保农业现代化发展,必须依靠科技进步。随着农村劳动力老龄化程度的加深。老龄劳动力作为新技术采纳的重要群体,将对新技术采用行为产生影响。所以探讨农村人口老龄化对农户生产技术采纳行为的影响问题显得尤为重要。当前国内外对于人口老龄化对农业生产的影响的研究多集中于种粮作物（玉米、水稻）,而对于经济作物的研究则较为匮乏。荔枝是我国南方的主要经济作物之一,经济价值较高,生产特性独特,对劳动力要求较高,对生产技术要求高。本文以我国荔枝农户为研究对象,探讨农户老龄化是否对其技术采纳行为产生影响。本研究在回顾和借鉴前人已有研究的基础上,利用我国荔枝龙眼技术体系产经团队2017年及2018年暑期对广东省和广西壮族自治区荔枝种植户的实地调查获取的数据。本文对广东省和广西壮族自治区荔枝种植户生产技术采纳行为现状进行描述统计分析,并在此基础上对年龄以65岁为界进行划分为青壮年农户及老龄农户两组,分析两组农户技术采纳行为的差异。而后,本文建立GLS回归模型及面板二值选择模型探讨农村人口老龄化对农户技术采纳数量及农户采用不同类型技术的影响,运用中介效应模型检验人口老龄化对农户技术采纳数量的影响是否是通过农户是否接受过技术培训这一因素影响的。主要得出以下结论:（1）我国荔枝产业农户采用荔枝生产技术的数量平均为3种左右;（2）荔枝生产中常见的十种技术受欢迎程度从高到低依次为:回缩、环割、疏花、疏果、间伐、高接换种、滴灌喷灌、套袋、水肥药一体化、防虫网;（3）农户使用劳动密集型及技术密集型技术较多,而资本密集型技术应用较少。（4）青壮年农户（即户主年龄在65岁以内的农户）采用技术数量要略高于老龄农户（即户主年龄65岁以上农户）,两组农户的技术密集型技术与劳动密集型技术使用率差异较明显,资本密集型技术使用率较为不明显;（5）农村人口老龄化对农户是否采用技术密集型技术具有显著性负向影响;（6）农户户主年龄对农户技术采纳数量的影响呈倒“U”型,年龄拐点在61岁左右。人口老龄化对农户技术采纳数量有显著性负向影响。农户户主年龄在61岁以内的农户年龄越大采纳技术的数量越多,农户户主年龄在61岁以上的农户年龄越大采纳技术的数量越少;（7）人口老龄化对是否参加过荔枝技术培训有负向影响。农户年龄对农户采用技术采纳数量的影响总效应为9.89%,直接效应8.48%,间接效应为1.40%。人口老龄化对技术采纳数量的影响一部分是由于农户是否接受过荔枝技术培训影响,影响效应为14.16%。

关键词：人口老龄化技术采纳行为荔枝农户

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卫生经济学评价报告指南及应用现状

中华预防医学杂志 2017年第3期51卷 276-280页

作者：肖军孙谨芳王琦琦亓晓么鸿雁中国疾病预防控制中心流行病学办公室北京102206 北京市朝阳区左家庄社区卫生服务中心

运用卫生经济学评价报告指南,可规范卫生经济评价的报告内容,提升卫生经济评价研究的质量.本文简要概述了卫生经济学评价报告指南的发展历史,并详细介绍了卫生经济研究质量评价（QHES）工具和卫生经济学评价报告标准共识（CHEERS）清单... 详细信息

运用卫生经济学评价报告指南,可规范卫生经济评价的报告内容,提升卫生经济评价研究的质量.本文简要概述了卫生经济学评价报告指南的发展历史,并详细介绍了卫生经济研究质量评价（QHES）工具和卫生经济学评价报告标准共识（CHEERS）清单两类指南的具体评价内容、应用现况和存在的优缺点.CHEERS清单只针对研究报告本身进行评价,而QHES工具对经济学研究的质量进行定量评价.两类指南虽侧重点不同,但在实际应用中可互为补充.

关键词：经济学,医学指南质量保证,卫生保健

基于Dubins曲线的轮式机旋耕作业CCPP算法

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农业装备与车辆工程 2024年第5期62卷 9-13页

作者：孙柱吕宪勇孙凯信李佩霏齐琪琪潍柴动力股份有限公司山东潍坊261000

针对轮式机在无人农场自主作业下的全覆盖路径规划(CCPP)问题,提出了一种基于Dubins曲线的轮式机旋耕作业全覆盖路径规划算法。对作业地块边界进行内缩处理后,采用梭形法作业形式将全覆盖规划路径分为正常作业规划与封圈作业规划2部分,... 详细信息

针对轮式机在无人农场自主作业下的全覆盖路径规划(CCPP)问题,提出了一种基于Dubins曲线的轮式机旋耕作业全覆盖路径规划算法。对作业地块边界进行内缩处理后,采用梭形法作业形式将全覆盖规划路径分为正常作业规划与封圈作业规划2部分,计算出的全覆盖规划路径通过关键控制点(进弯点与出弯点)表示。通过Dubins曲线对关键控制点拟合出满足车辆运动学的最短作业路径点,根据不同的作业形式与农艺要求在每个路径点上规划速度、机具状态以及当前航向角信息,以满足自主作业整体功能。实验结果表明,该算法在凸边形常见地块下的作业覆盖率达到95%以上,满足农艺要求。研究表明,该算法能够根据不同的作业机具参数与车辆运动学参数规划凸边形地块下从三角形地块到十边形地块下的全覆盖路径。

关键词： Dubins曲线全覆盖路径规划算法轮式机

_D-Proline capped gold nanoclusters for turn-on detection of serum Raltitrexed

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Chinese Chemical Letters 2019年第9期30卷 1627-1630页

作者： Weifei Lan qiqi Tan Juan qiao Gangyi Shen Li qi Beijing National Laboratory of Molecular Sciences Key Laboratory of Analytical Chemistry for Living Bio-systems Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China Department of Chemical Engineering Beijing Institute of Petro-chemical Technology Beijing 102617 China School of Pharmacy Minzu University of China Beijing 100081 China

With _D-proline as the reducing and capping agent, fluorescent gold nanoclusters were rapidly prepared(_D-Pro@AuNCs) within 10 min at 100℃. In the present of gold nanoparticles, the fluorescence of _DPro@AuNCs was remarkably quenched. Interestingly, based on the electrostatic interaction between anticancer drug Raltitrexed and gold nanoparticles induced fluorescence "turn-on" principle, a high selective assay for detection of Raltitrexed was established with the probe associating the fluorescence emission at 435 nm. The fluorescence intensity of _D-Pro@AuNCs linearly correlated with the concentration of Raltitrexed in the range from 5.0 mmol/L to 40.0 mmol/L(R^2= 0.999) and the limit of detection was 1.9 mmol/L. Further, after Raltitrexed was abdominal injected in rats, a metabolic approach was constructed with the prepared fluorescent probe. It showed great potential of AuNCs-based sensing probes for application in analysis of serum anticancer drugs.

关键词： D-Pro capped gold nanoclusters Fluorescent probe Turn on Sensing Serum RTX

A Catalog of Quasar Candidates Identified by Astrometric and Mid-infrared Methods in Gaia EDR3

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Research in Astronomy and Astrophysics 2023年第2期23卷 82-98页

作者： qiqi Wu Shilong Liao Zhaoxiang qi Hao Luo Zhenghong Tang Zihuang Cao Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories Chinese Academy of SciencesBeijing.100101China

Quasars are very important in materializing the reference *** excess emission of active galactic nuclei(AGNs) in the mid-infrared band can be used to identify quasar *** extremely distant and point-like objects,quasars also could be further selected by an astrometry *** the number of reliable quasar candidates is necessary in characterizing the properties of Gaia astrometric solution and evaluating the reliability of Gaia’s own quasars *** identify quasars by using appropriate All WISE [W1-W2] color and different combinations of astrometric *** with the contamination and completeness,the magnitude,astrometric properties,density distribution,and the morphological indexes of these selected quasars are *** obtain a quasar candidate catalog of 1,503,373 sources,which contains 1,186,690 candidates(78.9%) in common with the Gaia EDR3_AGN catalog and 316,683 newly identified quasar *** completeness of this catalog is around 80% compared to LQAC5,and the purity of the overall catalog is about 90%.We also found that the purity of quasar candidates selected by this method will decrease in the crowded sky area and the region with less WISE observations.

关键词： (galaxies:)quasars general-parallaxes-catalogs-astrometry

Direct Synthesis of Co-doped Graphene on Dielectric Substrates Using Solid Carbon Sources

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Nano-Micro Letters 2015年第4期7卷 368-373页

作者： qi Wang Pingping Zhang qiqi Zhuo Xiaoxin Lv Jiwei Wang Xuhui Sun Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Institute of Functional Nano & Soft Materials Soochow University

Direct synthesis of high-quality doped graphene on dielectric substrates without transfer is highly desired for simplified device processing in electronic ***,graphene synthesis directly on substrates suitable for device applications,though highly demanded,remains unattainable and ***,a simple and transfer-free synthesis of high-quality doped graphene on the dielectric substrate has been developed using a thin Cu layer as the top catalyst and polycyclic aromatic hydrocarbons as both carbon precursors and doping sources.N-doped and N,F-co-doped graphene have been achieved using TPB and F16Cu Pc as solid carbon sources,*** growth conditions were systematically optimized and the as-grown doped graphene were well *** growth strategy provides a controllable transfer-free route for high-quality doped graphene synthesis,which will facilitate the practical applications of graphene.

关键词： Graphene Solid carbon sources Transfer-free Doping and co-doping

Survey of Residents’ Satisfaction with the Environmental Sanitation of Key Public Places Under the Background of National Healthy City-China, 2021

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China CDC weekly 2023年第3期5卷 51-55页

作者： Jiaxin Dong qiqi Wang Jue Liu Hongyan Yao Xiao qi Jianjun Liu Chinese Center for Disease Control and Prevention BeijingChina School of Public Health Peking UniversityBeijingChina

National healthy city establishment is an urban construction activity with Chinese *** an essential part of establishing national healthy cities,environmental sanitation covers many environmental hygiene-related *** them,public place sanitation has been the focus and difficulty in China for many years,especially in key public places(small restaurants,small“internet cafes,”small hairdressers,small dance halls,small hotels,and small bathrooms),which are ubiquitous.

关键词： establishing restaurant faction

MEMS Huygens Clock Based on Synchronized Micromechanical Resonators

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Engineering 2024年第5期36卷 124-131页

作者： Xueyong Wei Mingke Xu qiqi Yang Liu Xu a Yonghong qi Ziming Ren Juan Ren Ronghua Huan Zhuangde Jiang State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710049China School of Construction Machinery Chang’an UniversityXi’an 710064China Department of Mechanics Zhejiang UniversityHangzhou 310027China

With the continuous miniaturization of electronic devices,microelectromechanical system(MEMS)oscillators that can be combined with integrated circuits have attracted increasing *** study reports a MEMS Huygens clock based on the synchronization principle,comprising two synchronized MEMS oscillators and a frequency compensation *** MEMS Huygens clock improved shorttime stability,improving the Allan deviation by a factor of 3.73 from 19.3 to 5.17 ppb at 1 s.A frequency compensation system based on the MEMS oscillator’s temperature-frequency characteristics was developed to compensate for the frequency shift of the MEMS Huygens clock by controlling the resonator *** effectively improved the long-term stability of the oscillator,with the Allan deviation improving by 1.6343105 times to 30.9 ppt at 6000 *** power consumption for compensating both oscillators simultaneously is only 2.85 mW·℃^(-1).Our comprehensive solution scheme provides a novel and precise engineering solution for achieving high-precision MEMS oscillators and extends synchronization applications in MEMS.

关键词： Frequency stability Huygens clock MEMS Oscillator Synchronization

Universal synthesis of metallophthalocyanine covalent organic frameworks as ultra-sensitive multifaceted electrochemical sensor

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Science China Chemistry 2024年第6期67卷 2092-2101页

作者： qi Liu qiqi Sun Yuming Zhang Hao Li Wenmiao Chen Yuexing Zhang Sirong Yu Yanli Chen Jianzhuang Jiang School of Materials Science and Engineering China University of Petroleum(East China)Qingdao266580China Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials School of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing100083China College of Chemistry and Chemical Engineering Dezhou UniversityDezhou253023China

The universal synthesis of highly stable covalent organic frameworks(COFs)for ultra-sensitive and multi-component electrochemical detection in different scenarios remains a great ***,a series of metallophthalocyanine-based twodimensional(2D)dioxin(DXI)-linked metalophthalocyanine(MPc)-n DXI-COFs(M=Ni,Zn;n=1,2)are afforded in high yield(80%-96%)by a facile trace-quinoline assisted one-pot condensation of tetracarbonitrile *** X-ray diffraction and electron microscopy investigations disclose their lamellar texture 2D network with AA stacking *** and calculation results elucidate that the 2DXI-linked MPc-2DXI-COFs provide the stronger built-in electronic field and more electrostatic/hydrogen bonding adsorption sites than DXI-linked MPc-DXI-COFs,and the lower electrode reaction Gibbs free energy and stronger adsorption of analytes at Ni Pc than Zn Pc unit,which grants Ni Pc-2DXI-COF excellent sensing properties for various analytes including neurotransmitters,organic pollutants,and heavy metal ions,with high sensitivity and low detection limit of 0.53 to 25.66 *** in binary and ternary systems and even in real-world conditions,simultaneous multi-component detection could be achieved.

关键词： covalent organic framework metallophthalocyanine 2D materials electrochemical sensors multi-component detection