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Study on energy threshold and spectral characteristics with spot radius based on LIBS technology

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Optoelectronics Letters 2021年第9期17卷 558-563页

作者： LI Honglian wang hongbao ZHANG Shizhao KANG Shasha wang Fan FANG Lide LI Xiaoting College of Quality and Technology Supervising Hebei UniversityBaoding 071000China National and Local Joint Engineering Center of Measuring Instruments and Metrology Systems Baoding 071000China

The aim of this study is to investigate the relationship between the laser-induced optical breakdown energy threshold and the spectral signal changes with the spot *** of all,using the avalanche breakdown threshold theory calculates the threshold avalanche ionization rateη*** with the theory of light intensity distribution and the relationship between pulse energy and peak power,numerical calculations have obtained the law of change of spot radius and threshold laser ***,the variation of the spectral signal-to-noise ratio(SNR)with the laser energy is measured according the experimental measurement,and the threshold laser energy required for optical breakdown at different spot radius is *** theoretical threshold model of the relationship between the threshold laser energy and the quadratic function of the spot radius obtained by numerical calculation is verified,and it is revised,the results show that the relative error between the revised theoretical threshold model and the experimental threshold model is less than 5.3%.At last,the influence of the spot radius on the spectral signal and electron density is also analyzed,it is found that both the spectral intensity and the electron density have a maximum at the spot radius of 11μ*** results show that it is necessary to find the best spot radius during the laser induced breakdown spectroscopy(LIBS)*** provides a reliable theoretical basis and experimental reference for further study of the influence of spot radius on LIBS technology measurement.

关键词： breakdown radius spectral

Continuous cropping of alfalfa (Medicago sativa L.) reduces bacterial diversity and simplifies cooccurrence networks in aeolian sandy soil

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Soil Ecology Letters 2022年第2期4卷 131-143页

作者： Yanxia Xu Junjie Liu Xuefeng Liu Hong Li Zhao Yang hongbao wang Xinyu Huang Lan Lan Yutong An Lujun Li Qin Yao Guanghua wang Branch of Animal Husbandry and Veterinary of Heilongjiang Academy of Agricultural Sciences Qiqihar 230202China Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 130102China University of Chinese Academy of Sciences Beijing 100049China

Alfalfa is a perennial herbaceous forage legume that is remarkably and negatively affected by ***,the contribution of the changes in bacterial communities to soil sickness in alfalfa have not been ***,we investigated bacterial community structures in response to monocropped alfalfa along the *** cropping remarkably reduced bacterial alpha diversity and altered community structures,and soil pH,total P and available P were strongly associated with the changes of bacterial diversity and community ***,10 years of monocropped alfalfa might be a demarcation point separating soil bacterial community structures into two obvious groups that containing soil samples collected in less and more than 10 *** relative abundances of copiotrophic bacteria of Actinobacteria and Gammaproteobacteria significantly increased with the extension of continuous cropping years,while the oligotrophic bacteria of Armatimonadetes,Chloroflexi,Firmicutes and Gemmatimonadetes showed the opposite changing *** those altered phyla,Actinobacteria,Chloroflexi,Alphaproteobacteria and Acidobacteria were the most important bacteria which contributed 50.86%of the community variations. Additionally, the relative abundances of nitrogen fixation bacteria ofBradyrhizobium and Mesorhizobium obviously increased with continuous cropping years, while theabundances of Arthrobacter, Bacillus, Burkholderiaceae and Microbacterium with potential functionsof solubilizing phosphorus and potassium remarkably decreased after long-term continuouscropping. Furthermore, bacterial cooccurrence patterns were significantly influenced by continuouscropping years, with long-term monocropped alfalfa simplifying the complexity of the cooccurrencenetworks. These findings enhanced our understandings and provided references for forecasting howsoil bacterial communities responds to monocropped alfalfa.

关键词： Aeolian sandy soil Continuously cropped alfalfa Cooccurrence networks 10 years Functional bacteria

Pollination Effects of Pear Trees by Honeybee and Its Influencing Factors

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Asian Agricultural Research 2023年第8期15卷 59-62页

作者： Jin wang Yaru wang hongbao wang Xiao LI Yingtao wang Yongbo wang Yong LI Shijiazhuang Pomology Institute Hebei Academy of Agricultural and Forestry SciencesShijiazhuang 050061China

[Objectives]To improve the yield and quality of different pear varieties by supplementary pollination.[Methods]The effects of bee pollination were compared with other pollination methods,and the effects of different factors on honeybee pollination were studied through experiments.[Results]Honeybee pollination significantly increased the number of fruit per *** addition,it could improve the single fruit weight,fruit shape and other quality indicators of *** pollination effect of honeybee was the best in all supplementary pollination *** pollination had good fruit setting effect on different pear varieties,but there were some differences in the effect of quality *** lime sulfur mixture and other measures could significantly affect the effects of honeybee pollination.[Conclusions]The research results prove the effectiveness of honeybee pollination technology in Hebei Province,and provide a certain reference for the establishment of a simple and practical artificial assisted pollination technology system.

关键词： Pear Honeybee Pollination

Effects of Bovine Embryos at Different Developmental Stages on Bisection Effect

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Agricultural Biotechnology 2021年第5期10卷 60-62页

作者： Guizhi TONG Yongsheng HAN hongbao wang Xintao LI Weixia wang Xueying SONG Branch of Animal Husbandry and Veterinary Heilongjiang Academy of Agricultural SciencesQiqihar 161005China Jilin Academy of Agricultural Sciences Changchun 136100China

[Objectives]This study was conducted to explore the effects of embryos at different developmental stages on the bisection effect of embryos,improve the efficiency of bovine embryo bisection,and facilitate the application of embryo bisection technology in cattle breeding.[Methods]The effects of two different bisection solutions on the bisection of morulae and blastocysts in vitro were *** morulae and blastocysts produced in vitro from cattle that developed to the 6th to 8th d were bisected by hands,and demi-embryos were cultured in *** development was observed.[Results]Morulae were bisected in PBS solution and PBS+0.2 mol/L sucrose,and the success rates of bisection were 50%and 95.2%,*** success rate of bisecting morulae in PBS+0.2 mol/L sucrose was significantly higher than that in PBS(P0.05).The success rates of blastocyst bisection in PBS solution and PBS+0.2 mol/L sucrose were 51.6%and 95.1%,*** success rate of blastocyst bisection in PBS+0.2 mol/L sucrose was significantly higher than that in PBS(P0.05).[Conclusions]There were no significant differences between the success rates of bisecting bovine morulae and blastocysts in PBS+0.2 mol/L sucrose,which were both significantly better than those in pure PBS bisection solution,proving that PBS+0.2 mol/L sucrose bisection solution is suitable for bovine embryo bisection.

关键词： Cattle Embryo division Success rate Development rate Morula Blastocyst

Performance and Cultivation Techniques of a New Pear Variety‘Jixiu’in Central Hebei Province

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Asian Agricultural Research 2022年第7期14卷 55-57页

作者： Yongbo wang Yaru wang Xiao LI Yingtao wang hongbao wang Jin wang Yong LI Shijiazhuang Fruit Research Institute Hebei Academy of Agricultural and Forestry SciencesShijiazhuang 050061China

‘Jixiu’is a new early ripening pear variety bred by‘Jimi’×‘Xinhang’,and its fruit quality is *** has performed well in central and southern *** paper introduces its botanical characteristics,growth phenology,growth and fruiting habits,pollination characteristics and disease resistance in central and southern Hebei.A set of suitable cultivation techniques for Jixiu pear were summarized,including pruning,fruit thinning and bagging,water and fertilizer management,pest and disease control and so on,which provided theoretical support for the popularization and demonstration of this new variety.

关键词： Pear New varieties Jixiu Precocity

上海市嘉定区全科医生工作满意度、心理资本和工作投入的调查及相关性分析

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中国全科医学 2020年第9期23卷 1144-1150页

作者：焦洁王宏保同济大学医学院上海市200092 上海市嘉定区外冈镇社区卫生服务中心 201806 同济大学附属杨浦医院上海市200090

背景全科医生是全科医疗服务的主要提供者。全科医生扮演的角色有临床医生、教育者、沟通者、守门人、管理者、组织协调者。我国的全科医学起步较晚,关于全科医生的研究不多。目的对上海市嘉定区的全科医生开展工作满意度、心理资本和... 详细信息

背景全科医生是全科医疗服务的主要提供者。全科医生扮演的角色有临床医生、教育者、沟通者、守门人、管理者、组织协调者。我国的全科医学起步较晚,关于全科医生的研究不多。目的对上海市嘉定区的全科医生开展工作满意度、心理资本和工作投入方面的调查研究,为当地社区卫生服务中心留住高质量人才提供帮助,并为卫生行政部门制定有关政策提供参考。方法2018年7月,以上海市嘉定区13家社区卫生服务中心的全科医生为研究对象,根据自愿原则开展问卷调查。收集全科医生的人口学资料〔性别、年龄、婚姻状况、户籍、教育背景、是否参加过住院医师规范化培训、职称、从事全科年限〕。采用明尼苏达职业满意度短式量表(外部满意度分量表、内部满意度分量表)调查全科医生工作满意度,心理资本问卷(PCQ)(自我效能、乐观、坚韧、希望)评价心理资本,工作投入评价使用工作投入量表(UWES)(活力、奉献、专注),分析工作满意度、心理资本与工作投入几个维度的相关性。结果共发放调查问卷245份,回收有效问卷235份,有效问卷回收率为95.9%。全科医生明尼苏达职业满意度短式量表总分为(71.54±12.60)分;心理资本问卷总分为(106.63±18.05)分,平均分为(4.44±0.75)分(满分6分);工作投入量表总分为(61.37±11.94)分,平均分为(3.61±0.70)分(满分5分)。内部满意度、外部满意度与心理资本、工作投入各维度呈正相关(P<0.05);多元线性回归分析结果显示,内部满意度和心理资本均对活力、奉献、专注有影响(P<0.05)。结论上海市嘉定区全科医生内部满意度、外部满意度与心理资本、工作投入各维度有相关性,且内部满意度和心理资本对工作投入各维度有影响。

关键词：全科医生职业满意心理资本工作投入量表

Risk management of stock index futures

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Journal of Southeast University(English Edition) 2008年第S1期24卷 191-195页

作者： Lü Xiaorong wang Fusheng wang hongbao(School of Management, Harbin Institute of Technology, Harbin 150001, China)

The Hong Kong Hang Seng index futures is taken as a study object and a method of empirical analysis is adopted in order to verify the validity of the application of the value-at-risk (VaR) method in the risk measurement of the stock index futures market. The results suggest that under normal market conditions it is feasible to apply the VaR method in the measurement of the market risks of stock index futures. The daily VaR value of the stock index futures provides a foreseeable profit and loss of the stock index futures. Financial supervisors can adjust their supervising strategies according to the daily VaR value. The speculators can adjust risk capital reserve rates in the same way. The application of this method in China's stock index futures market requires the solutions to specific problems: the absence of historical data, the difficult confirmation of non-risk interest rates etc.

关键词： value-at-risk (VaR) method risk management stock index futures (SIF)

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区域旅游商品深度开发探析

改革与战略 2009年第3期25卷 135-137页

作者：王红宝李小静石家庄经济学院商学院河北石家庄050031

旅游商品是旅游业的重要组成部分,经过多年的发展,各地都有了较丰富的旅游商品。但是旅游商品在深度开发过程过程中仍然存在一些问题,本文在区域旅游商品基本理论的基础上提出一些旅游商品深度开发的相关策略。

关键词：区域旅游商品旅游商品深度开发品牌

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客车侧翻碰撞中的乘员损伤研究

汽车工程 2014年第6期36卷 683-688页

作者：曹立波阮诚心陈杰王洪宝湖南大学汽车车身先进设计制造国家重点实验室长沙410082 胡志明工业大学汽车工程系越南胡志明市

首先利用MADYMO软件建立了某客车局部车身段的有限元与多体混合侧翻模型,并进行了侧翻仿真,其变形、碰撞加速度等仿真结果与相应的有限元仿真结果基本一致,说明了用有限元与多体混合模型取代有限元模型进行侧翻分析的有效性。据此接着... 详细信息

首先利用MADYMO软件建立了某客车局部车身段的有限元与多体混合侧翻模型,并进行了侧翻仿真,其变形、碰撞加速度等仿真结果与相应的有限元仿真结果基本一致,说明了用有限元与多体混合模型取代有限元模型进行侧翻分析的有效性。据此接着采用混合模型,在碰撞侧座椅上分别放置单个和两个佩戴两点式安全带的侧碰假人Euro SID-I,研究了侧翻过程中乘员的损伤情况以及乘员间的相互作用对乘员损伤的影响。结果表明,满足ECE R66法规要求的客车在侧翻过程中仍然可能对乘员造成较严重的胸部和腹部损伤,且客车侧翻过程中乘员相互作用会加剧乘员头部、颈部、胸部和腹部的损伤。

关键词：客车侧翻乘员相互作用乘员损伤