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Chinese Journal of Aeronautics 2024年第2期37卷 482-500页

作者： xiaohe wang Zengqiang CAO Yuehaoxuan wang Yingjiang GUO School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China NPU Xuhang Electromagnetic Technology Co. Ltd.Xi’an 710100China

As the controlled research of Dynamic Installation(DI)and Static Installation(SI),a new interference installation method was developed based on electromagnetic loading to enhance the mechanical properties of composite structures.Four different interference-fit sizes were considered,ranging from a net fit to 2.0%.The experiments were conducted to evaluate the installation resistance and the mechanical behavior of the joint under external loads.Meanwhile,an FFA model to model the stress distribution and damage behavior of the bolt-hole contact interface was established.The load-displacement curve and damage modes of experiments were used to verify the FEA results.The results show that the installation resistance during DI process was remarkably lower than that of SI process corresponding to all interference-fit sizes,and the stress amplitudes induced by interference were larger and widely distributed.The damage of the hole wall was positively correlated with interference fit size,but DI can significantly reduce the damage compared to SI.In performance tests,DI enhanced the static bearing capacity and extended longer fatigue life of the joints than SI.DI methods can be an effective way to achieve highly reliable interference joints in composite structures.

关键词： Carbon Fiber-Reinforced Polymer(CFRP) Bolted joints Interference-fit Electromagnetic installation Finite Element Analysis(FEA) Damage mechanics Bearing behavior

A Visualization Analysis of Medical and Prevention Fusion Research in China via CiteSpace

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China CDC weekly 2023年第23期5卷 519-524,I0001,I0002页

作者： Chen Jin Sijing Tu Yu Qian Xiaoyu Chen Zhiyi Peng xiaohe wang School of Public Health Hangzhou Normal UniversityHangzhou CityZhejiang ProvinceChina School of Public Health and Management Guangxi University of Chinese MedicineNanning CityGuangxi Zhuang Autonomous RegionChina

Since the 1990s,the acceleration of population aging has led to an increased prevalence of chronic diseases and enhanced public health awareness.Numerous countries have proposed healthcare reforms,with a focus on creating an“integrated care”model that aims to improve the quality of medical services and reduce costs(1–2).In 2008,the World Health Organization(WHO)put forward the concept of Integrated Delivery Systems(IDS),advocating for continuous,timely and integrated medical services.

关键词： services CiteSpace acceleration

Differential aluminum tolerance and absorption characteristics in Pinus massoniana seedlings colonized with ectomycorrhizal fungi of Lactarius deliciosus and Pisolithus tinctorius

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林业研究:英文版 2023年第5期34卷 1523-1533页

作者： Xirong Gu Hao Jia xiaohe wang Yanan Jiang Jie Li Xinhua He Centre of Excellence for Soil Biology College of Resources and EnvironmentSouthwest University2 Tiansheng RoadBeibeiChongqing 400715People’s Republic of China School of Biological Sciences University of Western Australia35 Stirling HighwayPerthWA 6009Australia Department of Land Air and Water ResourcesUniversity of California at DavisOne Shields AvenueDavisCA 95616USA

Plant tolerance to aluminum(Al)toxicity can be enhanced by an ectomycorrhizal(ECM)fungus through biological filtering or physical blockage.To understand the roles of ECM colonization in Al absorption with regard to Al tolerance,Pinus massoniana seedlings were inoculated with either Lactarius deliciosus(L.:Fr.)Gray isolate 2 or Pisolithus tinctorius(Pers.)Coker et Couch isolate 715 and cultivated in an acid yellow soil with or without 1.0 mM Al^(3+)irrigation for 10 weeks.Biomass production,Al bioaccumulation and transport in seedlings colonized by the two ECM fungi were compared,and the three absorption kinetics(pseudo-first order,pseudo-second order and intraparticle diffusion)models used to evaluate variances in root Al^(3+)absorption capacity.Results show that both fungi increased aboveground biomass and Al tolerance of P.massoniana seedlings,but L.deliciosus 2 was more effective than P.tinctorius 715.Lower Al absorption capacity,fewer available active sites and decreased affinity and boundary layer thickness for Al^(3+),and higher Al accumulation and translocation contributed to the increased Al tolerance in the ECM-inoculated seedlings.These results advance our understanding of the mechanisms and strategies in plant Alto lerance conferred by ECM fungi and show that inoculation with L.deliciosus will better enhance Al tolerance in P.massoniana seedlings used for forest plantation and ecosystem restoration in acidic soils,particularly in Southwest China and similar soils worldwide.

关键词： Acidic soil Aluminum accumulation Absorption characteristics Ectomycorrhizal fungi Pinus massoniana

Estimating the thickness of diffusive solid electrolyte interface

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Science China(Physics,Mechanics & Astronomy) 2017年第6期60卷 61-68页

作者： xiaohe wang WenHao Shen XianFu Huang JinLiang Zang YaPu Zhao State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

electrolyte. The properties of lithium-ion (Li-ion) battery, such as cycle life, irreversible capacity loss, self-discharge rate, electrode corrosion and safety are usually ascribed to the quality of the SEI, which are highly dependent on the thickness. Thus, understanding the formation mechanism and the SEI thickness is of prime interest. First, we apply dimensional analysis to obtain an explicit relation between the thickness and the number density in this study. Then the SEI thickness in the initial charge-discharge cycle is analyzed and estimated for the first time using the Cahn-Hilliard phase-field model. In addition, the SEI thickness by molecular dynamics simulation validates the theoretical results. It has been shown that the established model and the simulation in this paper estimate the SEI thickness concisely within order-of-magnitude of nanometers. Our results may help in evaluating the performance of SEI and assist the future design of Li-ion battery.

关键词：界面厚度固体电解质分子动力学模拟锂离子电池不可逆容量损失估算扩散时间估计

Reclassification of Oligodon ningshaanensis Yuan, 1983(Ophidia:Colubridae) into a New Genus, Stichophanes gen. nov. with Description on Its Malacophagous Behavior

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Asian Herpetological Research 2014年第3期5卷 137-149页

作者： xiaohe wang Kevin MESSENGER Ermi ZHAO Chaodong ZHU Chengdu Institute of Biology Chinese Academy of Sciences Department of Biological and Environmental Sciences Alabama A and M University Institute of Zoology Chinese Academy of Sciences

The complete mitochondrial cytb gene and the partial nuclear c-mos gene of Oligodon ningshaanensis Yuan, 1983 were sequenced and used for reconstructing the phylogenetic relationship of this taxon amongst alethinophidian snakes. Its strong affinity to the New World subfamily Dipsadinae and the Old World species Thermophis baileyi was inferred. Hemipenial morphology found by authors conflicts with the original description and its similarity with those of the dipsadid snakes is in accordance with our molecular results. Feeding tests show that O. ningshaanensis is a malacophagous predator, which is another matchless character for this species. This behavior is described and compared with other known slug- and snail-feeding snakes. The discovery of the particular position of our subject indicates that erecting a new genus is necessary accommodate this unique species.

关键词： Stichophanes gen. nov. ningshaanensis Dipsadinae molecular phylogeny hemipenial morphology,mollusks -predator

基于持续改进的师范专业课程评价有效性提升路径

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平顶山学院学报 2024年第3期39卷 103-109页

作者：王小鹤平顶山学院教师教育学院河南平顶山467036

师范专业认证背景下,大多数高校虽然进行了课程体系合理性评价和课程目标达成情况评价,却存在流于形式、持续改进机制不健全等问题,没有真正发挥评价在促进课程体系和课程教学持续改进中的作用。根据师范专业认证理念和课程评价的价值追... 详细信息

师范专业认证背景下,大多数高校虽然进行了课程体系合理性评价和课程目标达成情况评价,却存在流于形式、持续改进机制不健全等问题,没有真正发挥评价在促进课程体系和课程教学持续改进中的作用。根据师范专业认证理念和课程评价的价值追求,课程评价的有效性主要体现在课程评价自身的科学性、合理性及其对人才培养持续改进作用的发挥。为有效提升课程评价有效性,一要优化课程评价标准,提升评价的科学性水平;二要改革评价方式,提升评价的合理性水平;三要构建基于持续改进的课程评价运行机制和监督机制,从科学性、合理性、可行性三个方面三位一体提升课程评价的有效性。

关键词：课程评价有效性持续改进师范专业

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疏枝和刻伤对山莓果实产量和品质的影响

西北农林科技大学学报（自然科学版） 2024年第4期52卷 117-126页

作者：李杰辜夕容崔瑶胡佳王小河西南大学资源环境学院重庆北碚400716

【目的】探讨疏枝和刻伤对山莓果实产量和品质的影响,寻找适宜的整形修剪方式,为山莓的树体管理提供参考。【方法】以野生山莓2年生枝为试验对象,设置3种疏枝水平(不疏枝、疏除一级侧枝总数的1/5(轻度疏枝)和1/3(重度疏枝))和3种刻伤水... 详细信息

【目的】探讨疏枝和刻伤对山莓果实产量和品质的影响,寻找适宜的整形修剪方式,为山莓的树体管理提供参考。【方法】以野生山莓2年生枝为试验对象,设置3种疏枝水平(不疏枝、疏除一级侧枝总数的1/5(轻度疏枝)和1/3(重度疏枝))和3种刻伤水平(不刻伤、对1/2(轻度刻伤)和全部(重度刻伤)一级侧枝基部进行刻伤)的二因素三水平交叉分组试验,共9个处理,每个处理15株。在果熟期采集成熟果实,测定不同处理的单株产量、单果质量和果实有效成分含量,并采用隶属函数法评价疏枝和刻伤的综合效应。【结果】与不疏枝、不刻伤的对照相比,山莓单果质量和单株产量在除轻度疏枝结合重度刻伤外的其余处理下均显著增加;可溶性糖、可滴定酸和Vc含量在除轻度刻伤外的其余处理下均显著增加;SOD活性在除重度刻伤外的其余处理下均显著增加;总黄酮含量在各处理下均显著增加;鞣花酸含量仅在重度刻伤处理下显著增加,在其余处理下均显著降低;可溶性固形物含量仅在轻度疏枝结合轻度刻伤处理下显著增加,在其余处理下无显著改变;糖酸比和固酸比仅在轻度刻伤时显著增加,在其余处理下均显著降低;单果质量、单株产量和可溶性糖、可滴定酸、Vc、总黄酮含量以及SOD活性在疏枝和刻伤后的最大增幅分别达到36.3%,36.4%,24.5%,66.3%,29.6%,30.4%和40.5%。相比于对照,疏枝和刻伤的8种组合均显著提高了山莓果实的综合品质,其中以重度疏枝结合轻度刻伤后得到的果实综合品质最优,其总隶属函数值是对照的3.06倍。【结论】疏枝和刻伤技术均能提高山莓果实的产量和品质,其中疏除2年生枝上一级侧枝总数的1/3,同时对1/2一级侧枝基部上方进行刻伤后获得的果实综合品质最优,可推荐使用于山莓栽培实践。

关键词：果树修剪刻伤果实品质果实产量山莓栽培隶属函数

GNSS+1588v2高精度时间同步技术实现

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现代电子技术 2024年第5期47卷 42-45页

作者：王潇禾李雪梅廖麒成都理工大学机电工程学院四川成都610059

5G高精度时间同步是作为5G基站建设的重要要求之一,但随着5G室内基站数量呈现几何级数增长,使用GNSS授时同步时钟势必会存在很多限制,比如容易受场地环境的影响无法获取卫星信号、GNSS接收机的成本突增,所以使用GNSS时钟同步技术不适合5... 详细信息

5G高精度时间同步是作为5G基站建设的重要要求之一,但随着5G室内基站数量呈现几何级数增长,使用GNSS授时同步时钟势必会存在很多限制,比如容易受场地环境的影响无法获取卫星信号、GNSS接收机的成本突增,所以使用GNSS时钟同步技术不适合5G基站的大规模部署。文中提出一种基于OCTEON Fusion平台的GNSS+1588v2时间同步技术实现方案,其特点在于使用层次式同步,通过GNSS给一个时钟系统同步授时,被授时的时钟系统作为主时钟系统通过1588v2地面链路给下一级时钟系统授时,实现一个GNSS给多个基站同步授时。文中对现有的GNSS时钟同步授时进行分析,在此基础上提出一种基于OCTEON Fusion平台的GNSS+1588v2时间同步方案,在对此方案的同步精度和同步稳定性的测试中,时钟同步精度达到10 ns左右,同步稳定性达到10 ns以内。

关键词： 5G 1588v2 GNSS 时间同步同步精度同步稳定性

基于IPA模型的三级公立医院绩效考核指标重要性和有效性认知分析

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中国医院管理 2024年第7期44卷 59-62页

作者：申飞虎王小合宋慧敏南方医科大学第五附属医院广东广州510900 杭州师范大学公共卫生学院浙江杭州31112 东莞城市学院广东东莞523000 澳门科技大学中国澳门999078

目的研究对三级公立医院绩效考核方案中55个三级指标重要性与有效性的认知。方法从被考核者的角度出发,采用调查问卷、重要性绩效分析(Importance Performance Analysis,IPA)和焦点小组访谈的方法对指标进行重要性和有效性认知研究。结... 详细信息

目的研究对三级公立医院绩效考核方案中55个三级指标重要性与有效性的认知。方法从被考核者的角度出发,采用调查问卷、重要性绩效分析(Importance Performance Analysis,IPA)和焦点小组访谈的方法对指标进行重要性和有效性认知研究。结果重要性和有效性整体认知较高,绩效考核指标体系能较好地评价三级公立医院的发展水平。指标的重要性和有效性认知之间普遍存在差异,部分指标存在重要性、有效性认知不足的问题。结论绩效考核政策制定方可根据政策实施情况,忽略与利益相关者关系紧密的指标后,对指标重新监测分析,进行动态调整,增减三级指标,调整指标权重,优化指标内容,使指标测量方式精准化,提高三级公立医院绩效考核评价效果。

关键词：三级公立医院绩效考核指标重要性绩效分析

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基于电磁加载的冲击测试方法及应用

航空制造技术 2024年第7期67卷 112-124页

作者：王晓荷曹增强郭映江郭程翔王玥浩轩西北工业大学西安710072 陕西大工旭航有限公司西安710072

针对国防军工和航空航天对材料、结构或产品进行冲击试验的广泛需求,以及现有冲击测试技术在加载速度、加载力、安全隐患及模式单一等方面存在的问题,提出了基于电磁加载的冲击测试方法,开发了电磁加载的冲击测试系统。电磁力驱动的冲... 详细信息

针对国防军工和航空航天对材料、结构或产品进行冲击试验的广泛需求,以及现有冲击测试技术在加载速度、加载力、安全隐患及模式单一等方面存在的问题,提出了基于电磁加载的冲击测试方法,开发了电磁加载的冲击测试系统。电磁力驱动的冲击测试方法可针对不同的试验对象和不同试验要求,通过调整电源控制参数(主要是电容值和充电电压值)实现加载脉宽、载荷幅值及加载速度的精确调整和控制;通过改变电磁加载头方向便可实现拉伸-压缩试验的快速转换。此外,针对结构受复杂冲击加载的动态测试需求,基于电磁驱动的多轴多向加载可通过控制程序精准控制多驱动头同时放电,从而实现多轴多向同步加载,保证了作用于试件材料上的各向冲击载荷的同步性。因此,基于电磁加载的测试技术具有可控性好、重复性高、测试精度和试验效率高等优势,基于电磁加载的冲击测试解决了传统测试方法加载速度范围小、测试应变率范围有限、大加载力冲击测试难等难题,实现了冲击测试试验安全、稳定、可靠及更加精确的控制和测量。

关键词：电磁加载动态冲击电磁霍普金森杆低速冲击应变率