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女子射箭个人项目世界竞技格局及我国备战巴黎奥运会策略研究

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体育科技文献通报 2023年第4期31卷 1-5,166页

作者：王西贝李晓峰闫育东李紫薇李凝鑫天津体育学院天津300000 北京市芦城体育运动技术学校北京射箭队女队北京102612 天津体育学院运动训练学院天津301617 天津体育学院体育教育学院天津301617

女子射箭项目是我国传统优势项目,也是有望在奥运会上夺牌的“潜优势项目”,在我国竞技体育中占有重要地位。当今世界射箭项目竞争日益激烈,我国奥运会备战形势严峻,除强势的韩国“梦之队”外,各国在射箭项目比赛中的进步有目共睹。为... 详细信息

女子射箭项目是我国传统优势项目,也是有望在奥运会上夺牌的“潜优势项目”,在我国竞技体育中占有重要地位。当今世界射箭项目竞争日益激烈,我国奥运会备战形势严峻,除强势的韩国“梦之队”外,各国在射箭项目比赛中的进步有目共睹。为实现我国2024年巴黎奥运会射箭项目取得好成绩的目标,本文以我国女子射箭项目主要竞争国家及重点运动员为研究对象,运用文献资料、比较分析、逻辑分析等研究方法,通过统计、对比1988-2020年间的九届奥运会、2012-2020年近三届奥运会、2022射箭世界杯四站比赛的成绩,对该项目世界格局及重点运动员进行全面梳理分析,结果表明:韩国、英国、中国台北、日本、美国、墨西哥、俄罗斯奥运队(ROC)和意大利是我国女子射箭项目的主要竞争国家或地区。本文最后借鉴世界强手经验,结合我国实际,提出了中国女子射箭项目的奥运备战对策建议。

关键词：巴黎奥运会主要竞争国家射箭项目备战策略

含dMAR真核表达载体的构建及影响EGFP表达的研究

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首都医科大学学报 2005年第2期26卷 159-162页

作者：孙丽翠祁雅慧张静宜闫豫东殷红首都医科大学实验中心

目的　研究dMAR对EGFP基因表达的调控作用。方法　用Kpn -I酶切pGFP/MAR,回收含MAR下游850bp的片段dMAR,与Kpn I酶切回收的pEGFP-C1 载体连接,Hind Ⅲ酶切鉴定方向,构建正向、反向连接的真核表达载体pEGFP/dMAR′和pEGFP/dMAR。将该表... 详细信息

目的　研究dMAR对EGFP基因表达的调控作用。方法　用Kpn -I酶切pGFP/MAR,回收含MAR下游850bp的片段dMAR,与Kpn I酶切回收的pEGFP-C1 载体连接,Hind Ⅲ酶切鉴定方向,构建正向、反向连接的真核表达载体pEGFP/dMAR′和pEGFP/dMAR。将该表达载体转染COS7细胞,荧光显微镜观察EGFP的表达并采用流式细胞术进行荧光定量。结果　pEGFP- C1,pEGFP/dMAR′和pEGFP/dMAR转染后48 h EGFP的表达量分别为45.1%、40.5%和11.3%。结论　pEGFP/dMAR显著抑制了EGFP的表达,pEGFP/dMAR′的增强表达作用不明显。

关键词：真核表达载体表达的研究 pEGFP COS7细胞 HindⅢ 流式细胞术调控作用基因表达酶切鉴定荧光定量微镜观察表达作用 MAR Kpn 表达量回收连接转染

Non-negligible factors in low-pressure sprinkler irrigation:droplet impact angle and shear stress

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Journal of Arid Land 2022年第11期14卷 1293-1316页

作者： HUI Xin ZHENG yudong MUHAMMAD Rizwan Shoukat TAN Haibin yan Haijun College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Engineering Research Center of Agricultural Water-Saving and Water Resources Ministry of EducationBeijing 100083China Semi-arid Agriculture Engineering&Technology Research Center of China Shijiazhuang 050051China

Droplet shear stress is considered as an important indicator that reflects soil erosion in sprinkler irrigation more accurately than kinetic energy,and the effect of droplet impact angle on the shear stress cannot be *** this study,radial distribution of droplet impact angles,velocities,and shear stresses were investigated using a two-dimensional video disdrometer with three types of low-pressure sprinkler(Nelson D3000,R3000,and Komet KPT)under two operating pressures(103 and 138 kPa)and three nozzle diameters(3.97,5.95,and 7.94 mm).Furthermore,the relationships among these characteristical parameters of droplet were analyzed,and their influencing factors were comprehensively *** various types of sprinkler,operating pressures,and nozzle diameters,the smaller impact angles and larger velocities of droplets were found to occur closer to the sprinkler,resulting in relatively low droplet shear *** increase in distance from the sprinkler caused the droplet impact angle to decrease and velocity to increase,which contributed to a significant increase in the shear stress that reached the peak value at the end of the ***,the end of the jet was the most prone to soil erosion in the radial direction,and the soil erosion in sprinkler irrigation could not only be attributed to the droplet kinetic energy,but also needed to be combined with the analysis of its shear *** comparing the radial distributions of average droplet shear stresses among the three types of sprinklers,D3000 exhibited the largest value(26.94-3313.51 N/m^(2)),followed by R3000(33.34-2650.80 N/m^(2)),and KPT(16.15-2485.69 N/m^(2)).From the perspective of minimizing the risk of soil erosion,KPT sprinkler was more suitable for low-pressure sprinkler irrigation than D3000 and R3000 *** addition to selecting the appropriate sprinkler type to reduce the droplet shear stress,a suitable sprinkler spacing could also provide acceptable results,because the distance

关键词： center pivot irrigation system water droplet universal model soil erosion water-saving irrigation

Warship detection in Smoke Screen Interference Based on Fractal and Rough Set Theory

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Warship detection in Smoke Screen Interference Based on Frac...

白藜芦醇抑制巨噬细胞中NF-κB通路发挥抗肝纤维化作用

2012 IEEE 11th International Conference on Signal Processing(ICSP 2012)

作者： LI Zhiguo yan Xiaoke Bai yudong Unit 91404 PLA

ISBN: (纸本)9781467321969

In IR images, the same kind of natural scenes are self-similarity statistically, namely their fractal dimension remains unchanged approximately. At edges, however, the dimension is underestimated, because edges add a deterministic component to the surface which is not assumed to be presented for the purpose of calculation of the fractal dimension. Thus, the local degree of ’fractality’ is used to differentiate the regions-of-interest （ROI） from the clutter background. Then, the warship is detected based on indiscemibility relation of Rough sets （RS） theory and is recognized based on the geometric characters of warship. Experiments on the image tracker based on TMS320C6416 were conducted, and the results demonstrated that the approach performs well in automatic recognition accuracy and computational efficiency.

关键词： Warship Smoke Screen Fractal Rough Set theory

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胃肠病学和肝病学杂志 2020年第5期29卷 576-580页

作者：闫玉栋姜海行罗薇胡榜利于冰李凡付艳君广西医科大学第一附属医院消化内科广西南宁530021 广西医科大学附属肿瘤医院实验研究部广西医科大学第二附属医院消化内科湖南省长沙市第四人民医院药剂科桂林医学院附属医院

目的探讨白藜芦醇(Resveratrol)改善肝纤维化的机制是否通过抑制NF-κB通路来调节巨噬细胞活性实现。方法将实验小鼠随机分为3组,分别给予橄榄油、橄榄油+四氯化碳(CCl4)、橄榄油+CCl4+白藜芦醇腹腔注射,用Masson三重染色法评估肝纤维... 详细信息

目的探讨白藜芦醇(Resveratrol)改善肝纤维化的机制是否通过抑制NF-κB通路来调节巨噬细胞活性实现。方法将实验小鼠随机分为3组,分别给予橄榄油、橄榄油+四氯化碳(CCl4)、橄榄油+CCl4+白藜芦醇腹腔注射,用Masson三重染色法评估肝纤维化严重程度,NF-κBmRNA及蛋白表达水平用RT-PCR和Westernblotting法测定;用RAW264.7巨噬细胞分别建立M0型、M1型和白藜芦醇干预的M1型巨噬细胞模型,再测定各组模型中NF-κBmRNA和蛋白表达水平。结果 Masson染色结果提示,白藜芦醇有改善小鼠肝纤维化的作用。RT-PCR和Westernblotting方法显示肝纤维化组织中NF-κBmRNA和蛋白表达水平升高,而白藜芦醇干预后表达水平下降。NF-κBmRNA和蛋白质的表达量在M1型巨噬细胞中较M0型明显升高,其表达水平在白藜芦醇干预M1型巨噬细胞模型后下降。结论 NF-κB通路活性在纤维化的肝组织及M1型巨噬细胞中明显增高,白藜芦醇可通过降低两者中NF-κB通路活性达到抗肝纤维化的作用。

关键词：肝纤维化巨噬细胞白藜芦醇 NF-κB通路

A separation column for liquid mixture based on phase transform:Experiment and simulation

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Chinese Journal of Chemical Engineering 2024年第10期74卷 144-153页

作者： Mengjie Liu Weiqun Gao Kexin yan yudong Li Bihong Li Jiating Zhang Weizhen Sun Ling Zhao State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

The concentric internally heat-integrated distillation column(HIDi C) has advantages of low energy consumption and high thermodynamic efficiency. However, its drawbacks of limited heat transfer area,complex internal structure, and large number of control parameters hinder its widespread industrial applications. To solve these challenges, in this work a novel sleeve-like concentric heat-integrated separation column, namely temperature-controlled phase change column(TCPC), was developed to separate liquid mixtures in a more effective and energy-saving way with reflux section being moved and trays being replaced with spiral corrugation blades. The comprehensive performances of TCPC in ethanol-water system was firstly evaluated by experiments. The results showed that TCPC performs well in ethanol-water separation due to the internal spiral corrugation significantly reducing the vapor-liquid contact in separation section. Meanwhile, compared to the concentric HIDi C, TCPC has a higher total heat transfer coefficient due to the larger heat transfer area. Computational fluid dynamics simulation reveals the internal design of TCPC inducing secondary vortices of the vapor, enhancing condensation heat transfer and separation efficiency. Further, increasing the mass flow rate within a certain range would enhance the comprehensive performance factor and lead to more effective separation.

关键词： Temperature-controlled phase change column Spiral corrugation blade Heat integration Computational fluid dynamics

Probing martensitic transformation,kinetics,elastic and magnetic properties of Ni2-xMn1.5In0.5Cox alloys

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Journal of Materials Science & Technology 2020年第9期44卷 31-41页

作者： Xinzeng Liang Jing Bai Jianglong Gu Haile yan yudong Zhang Claude Esling Xiang Zhao Liang Zuo Key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao066004China Hebei Provincial Laboratory for Dielectric and Electrolyte Functional Materials Qinhuangdao066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China Laboratoire d’étude des Microstructures et de Mécanique des Matériaux LEM3 CNRSUMR 7239University of Lorraine57045MetzFrance

The martensitic transformation,kinetics,elastic and magnetic properties of the Ni2-xMn1.5In0.5Cox(x=0-0.33)ferromagnetic shape memory alloys were investigated experimentally and theoretically by first-principles ***-principles calculations show that Co directly occupies the site of Ni sublattice,and Co atoms prefer to distribute evenly in the *** optimized lattice constants are consistent with the experimental *** martensitic transformation paths are as follows:PA↔FA↔6MFIM↔NMFIM when 0≤x<0.25;PA↔FA↔6MFM↔NMFIM with 0.25≤x<0.3 and PA↔FA↔NMFM with 0.3≤x≤0.33 for Ni2-xMn1.5In0.5Cox(x=0-0.33)*** fundamental reasons for the decrease of TM with increasing Co content are explained from the aspects of first-principles calculations and martensitic transformation *** component interval of the magnetostructural coupling is determined as 0≤x≤0.25 by first-principles ***,the origin of the demagnetization effect during martensitic transformation is attributed to the shortening of the nearest neighboring distances for Ni-Ni(Co)and *** the theoretical calculations with experimental results,it is verified that the TM of the Co6 alloy is near room temperature and its magnetization differenceM is 94.6 emu/***,magnetic materials with high performance can be obtained,which may be useful for new magnetic applications.

关键词： Ni-Mn-In-Co First-principles calculations Martensitic transformation Kinetics Elastic and magnetic property

Investigation of martensitic transformation behavior in Ni-Mn-In Heusler alloy from a first-principles study

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Journal of Materials Science & Technology 2020年第23期58卷 100-106页

作者： Jinlong Wang Jing Bai Jianglong Gu Haile yan yudong Zhang Claude Esling Xiang Zhao Liang Zuo Key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China Laboratoire d’Étude des Microstructures et de Mécanique des Matériaux LEM3CNRSUMR 7239University of Lorraine57045MetzFrance Hebei Provincial Laboratory for Dielectric and Electrolyte Functional Materials Qinhuangdao066004China

Composition dependence of martensitic transformations as well as the magnetic properties for the Ni_2 Mn_(1+x)In_(1-x)(0.25≤x≤0.58)alloys were investigated by using the first-principles *** results demonstrate that the stability of parent austenite(A)decreases gradually with increasing Mn content whilst it is opposite for the martensitic *** causes the total energy difference between the austenite and martensite phases increscent with increasing Mn *** x=0.33,the martensite transformation during cooling is PA→FA→*** x≥0.42,an intermartensitic transformation occurs from modulated 6 M martensite to non-modulated(NM)martensite with the martensite transformation sequence of PA→FA→6 M→*** martensitic transformation from austenite to martensite accompanies the transition from ferromagnetic to ferrimagnetic *** is a typical magneto-structural coupling *** analysis of the density of states demonstrates that the Ni 3 d state plays an important role in the phase stability.

关键词： Ni-Mn-In Shape memory alloy Martensitic transformation Magnetic properties First-principles calculations

Multifunctional MgF_2/Polydopamine Coating on Mg Alloy for Vascular Stent Application

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Journal of Materials Science & Technology 2015年第7期31卷 733-743页

作者： Xiaoli Liu Zhen Zhen Jing Liu Tingfei Xi yudong Zheng Shaokang Guan Yufeng Zheng yan Cheng School of Materials Science and Technology University of Science and Technology Beijing Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking University Shenzhen Research Institute Peking University Materials Research Center School of Materials Science and EngineeringZhengzhou University

Mg alloy is of great potential in the application of vascular stent due to its degradation in physical environment and proper mechanical property. However its mechanical integrity does not meet the clinical requirement clue to relatively fast degradation. Besides, in order to accelerate the re- endothelialization of Mg-based stents, it needs surface modification to improve the attachment, growth and adhesion of endothelial cells （ECs）. To solve the main obstacles, an anti-corrosion and quick endothelialization coating was prepared on novel Mg-Zn-Y-Ncl alloy via a simple two-step immersion method in the present study, first in hydrofluoric acid （HF） then in dopamine tris-Hydrochloric acid （tris -HCI） solution. The coating was uniform and thin, which consisted of two layers--the upper was pol- yclopamine （PDA） layer and the lower was MgF2 layer. The alloy with the coating demonstrated dramatic corrosion resistance enhancement in vitro by immersion test and electrochemical test. Moreover the HF- PDA-treated Mg alloy exhibited great performance of cell adhesion and proliferation. The coating created a favorable environment for ECs to have a competitive advantage over vascular smooth muscle ceils （VSMCs）, which was preferable for re-enclothelialization. The results suggest that HF-PDA-treatecl Mg -Zn-Y-Nd alloy has great potential in the application of vascular stent and the surface coating method is of great aPPlication value in biodegraclable Mg alloy stent clue to its simplicity and effectiveness.

关键词： Mg-Zn-Y-Nd alloyVascular stentHF converted layerPolydopamineCorrosion resistanceRe-endotheliazation