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The high frequency acoustic radiation from the boundary layer of an axisymmetric body

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Chinese Journal of Acoustics 2001年第2期20卷 103-110页

作者： LI Fuxin ma Lin (College of marine Engineering, Northwestern Polytechnical University Xi’an 710072) ma Zhiming (College oj Navy Aeronautics Engineering Qingdao 266001) College of marine Engineering Northwestern Polytechnical University Xi'an 710072 College of Navy Aeronautics Engineering Qingdao 266001

The mechanism of acoustic radiation from the boundary layer of an axisymmetric body is analyzed, and its sound pressure spectrum is predicted. It is shown that the acoustic radiation results from the transition region and the turbulent boundary layer; and that the acoustic radiation from transition region is predominant at low frequencies; while the turbulent boundary layer has the decisive effect on acoustic radiation at high frequencies. The calculated values are in good agreement with the experimental data.

关键词： The high frequency acoustic radiation from the boundary layer of an axisymmetric body high

固定矫治器联合肌功能锻炼对安氏Ⅱ类畸形患者咬合功能及口腔健康的影响分析

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中国医疗美容 2024年第1期14卷 58-61页

作者：韩晶刘梦蕾丁丹丹马海萍刘鲁慧西宁市口腔医院正畸科青海西宁810000 青海省交通医院口腔科青海西宁810000

目的探析固定矫治器与肌功能锻炼治疗安氏II类畸形患者,对其口腔健康、咬合功能的作用影响。方法项目起止时间2022年10月至2023年10月,研究对象选择在我院口腔科通过固定矫治器与肌功能联合治疗的92例安氏Ⅱ类畸形患者,对比治疗前、后... 详细信息

目的探析固定矫治器与肌功能锻炼治疗安氏II类畸形患者,对其口腔健康、咬合功能的作用影响。方法项目起止时间2022年10月至2023年10月,研究对象选择在我院口腔科通过固定矫治器与肌功能联合治疗的92例安氏Ⅱ类畸形患者,对比治疗前、后患者口腔健康、咬合功能、硬/软组织改善程度等情况。结果治疗后患者咬合功能MMCOF(指力中点最大位移)、AOF(指力不对称指数)、COF(指力中心点位置)等指标较治疗前明显降低(Poj(指覆颌)等指标水平明显降低(P<0.05);而LI-NB(指下切牙倾斜度)、LI-MP(指下中切牙与下颌平面夹角)、SNB(指下齿槽座角)等指标水平明显提高(P<0.05)。结论固定矫治器与肌功能锻炼联合治疗安氏II类畸形患者,可明显改善患者咬合功能、硬组织,对其口腔健康具有积极的影响。

关键词：固定矫治器肌功能锻炼安氏Ⅱ类畸形咬合功能口腔健康

Supercapacitor Performance of Hollow Carbon Spheres by Direct Pyrolysis of Melamine-formaldehyde Resin Spheres

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Chemical Research in Chinese Universities 2013年第4期29卷 735-742页

作者： ma Fang-wei SUN Li-ping ZHAO Hui LI Qiang HUO Li-hua XIA Tian GAO Shan Key Laboratory of Functional Inorganic material Chemistry Ministry oJ Education School of Chemistry and Material Science Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion of Heilongjiang Province Heilong/iang University Harbin 150080 P. R. China

The nitrogen and oxygen co-doped hollow carbon spheres（HCSs） were prepared via a simple pyrolysis of solid melamine-formaldhyde resin spheres. The carbonization temperature has an important influence on the specific surface area, pore-size distribution and heteroatom contents of HCSs. The synergistic effects of those physical and chemical properties on supercapacitor performance were systematically investigated. Among the HCSs obtained at different temperatures, HCSs-800（co-doped HCSs at 800℃） exhibits the best reversible specific capacitance in 2 mol/L H2SO4 electrolyte and meanwhile maintains a high-class capacitance retention capability. The nitrogen heteroatoms were confirmed to play a crucial role in improving capacitance in an acid medium. This kind of nitrogen doved HCSs is a potential candidate for an efficient electrode material for supercapacitors.

关键词： Hollow carbon sphere Pyrolysis Melamine-formaldehyde resin Supercapacitor Nitrogen-dope

Multiscale carbon foam confining single iron atoms for efficient electrocatalytic CO2 reduction to CO

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Nano Research 2019年第9期12卷 2313-2317页

作者： Zheng Zhang Chao ma Yunchuan Tu Rui Si Jie Wei Shuhong Zhang Zhen Wang Jian-Feng Li Ye Wang Dehui Deng State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry far Energy Materials (iChEM)College oj Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Catalysis iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China College of materials Science and Engineering Hunan UniversityChangsha 410082China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China materials and Structural Analysis Division Thermo Fisher ScientificInternational BioislandGuangzhou 510320China

Electrocatalytic CO2 reduction to CO is a sustainable process for energy ***,this process is still hindered by the diffusi limited mass transfer,low electrical conductivity and catalytic ***,new strategies for catalyst design should be adopted to solve these problems and improve the electrocatalytic performa nee for CO ***,we report a multiscale carb on foam confining〔single iron atoms prepared with the assistant of S1O2 *** pore-enriched environment at the macro-scale facilitates the diffusion of reacta nts and *** graphe ne nano sheets at the nano-scale promote the charge tran sfer duri ng the *** single iron atoms con fined in carb on matrix at the atomic-scale provide the active sites for electrocatalytic CO2 reductio n to *** optimized catalyst achieves a CO Faradaic efficiency of 94.9%at a moderate potential of-0.5 V ***,the performance can be maintained over 60 hours due to the stable single iron atoms coordi nated with four n itroge n atoms in the carb on *** work provides a promising strategy to improve both the activity and stability of single atom catalysts for electrocatalytic CO2 reduction to CO.

关键词： CO2 reduction electrocatalysis multiscale structure carbon foam single iron atoms

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鉴别辐照液态食品的电化学方法

江苏农业学报 1988年第4期 40-44页

作者：谢宗传马力师双平江苏省农业科学院原子能农业利用研究所

应用60Co-γ射线辐照薯干白酒、红萄萄酒、酱油、醋、苹果、糖水桔子等14种食品,分析辐照前后的电化学特性.其电位值有明显变化,特别是薯干白酒,辐照前后可相差5倍,并且在辐照85天仍比对照高3倍;其电阻率辐照组也比对照组高20％左右。增... 详细信息

应用60Co-γ射线辐照薯干白酒、红萄萄酒、酱油、醋、苹果、糖水桔子等14种食品,分析辐照前后的电化学特性.其电位值有明显变化,特别是薯干白酒,辐照前后可相差5倍,并且在辐照85天仍比对照高3倍;其电阻率辐照组也比对照组高20％左右。增加0.1％H2O2再辐照,其电位值的变化与对照相比,差异更大。

关键词：辐照食品电化学电导

分子氧在锐钛矿型TiO2表面的光助吸附和光助脱附

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感光科学与光化学 1988年第2期 7-12页

作者：王利盛马福泰俞稼镛杭州大学化学系中国科学院感光化学研究所杭州浙江工学院化工系杭州北京

本文采用真空-质谱技术研究了紫外线照射下分子氧在锐钛矿型TiO2表面的吸附和脱附机理。氧光助吸附后,锐钛矿表面成为活化表面。活化表面的O2-（分子氧在锐钛矿表面的吸附态）在1.33×10-3Pa的真空中,在能量大于锐钛矿禁带宽度2.9eV的... 详细信息

本文采用真空-质谱技术研究了紫外线照射下分子氧在锐钛矿型TiO2表面的吸附和脱附机理。氧光助吸附后,锐钛矿表面成为活化表面。活化表面的O2-（分子氧在锐钛矿表面的吸附态）在1.33×10-3Pa的真空中,在能量大于锐钛矿禁带宽度2.9eV的紫外线照射下成为分子氧脱附,氧脱附后的表面在无紫外线照射的氧气氛中对分子氧有吸附作用,该O2-饱和吸附量大于相同氧压下紫外线照射下O2的饱和吸附量。在氧压和光强度相同的条件下,O2-吸附量与表面羟基化程度呈线性关系。

关键词：锐钛矿分子氧光助吸附光助脱附

Structure and material Design of High Performance Functional Refractories for High-speed Continuous Casting

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China's Refractories 2012年第1期21卷 1-5页

作者： LI Hongxia,LIU Guoqi,YANG Wengang,YU Jianbin,ma Tianfei,QIAN Fan State Key Laboratory of Advanced Refractories,Sinosteel Luoyang Institute of Refractories Research Co. ,Ltd. ,Luoyang 471039,China State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research Co. Ltd Luoyang 471039 China

Functional refractories, including submerged entry ,mzzle （SEN） , ladle shroud and monolithic stopper, are ,he key refractories for continuous casting. Drh,en by the demand （f high-speed continuous casting, traditional （unetional refractories ji,il to meet the needs of long span life, and high perfomance .[imctional refractories for continuous casting are hwreasingly required. Through structure and material ***, the performance of functional refiactories is significant5 improved. In this paper, some research adt,ances on functional refractories for continuous casting wetr mentiotted. Through numerical qmdeling and hot simulation, the service life of non-pretreating ladle shroud u,as increased front 8 h to more ＇ban 12 h. Thraugh the water modeling, the flow patterns in the mold wetr significantly improved attd through hot simulation and material design, the sen;ice liJb and eliability oj SEN were also significantly improved.

关键词： functional refractories continuous casting hotsimulation

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系统性血管炎肺受累

中国实用内科杂志 2020年第4期40卷 270-274页

作者：张莉芸马丹山西白求恩医院山西医学科学院风湿免疫科山西太原030032

系统性血管炎是风湿性疾病乃至内科领域最具有挑战性、最复杂,也是最常见的一类疑难性疾病,可累及全身多系统。肺脏作为人体最重要的器官之一,有丰富的血管床,是系统性血管炎最常累及的部位,可表现为间质性肺疾病、弥漫性肺泡出血、肺... 详细信息

系统性血管炎是风湿性疾病乃至内科领域最具有挑战性、最复杂,也是最常见的一类疑难性疾病,可累及全身多系统。肺脏作为人体最重要的器官之一,有丰富的血管床,是系统性血管炎最常累及的部位,可表现为间质性肺疾病、弥漫性肺泡出血、肺部结节、肺动脉高压、肺动脉瘤、肺动静脉血栓形成等,易与感染、肿瘤等疾病相混淆。由于其发生率高,临床表现复杂,诊断鉴别困难,预后差,因此正确认识系统性血管炎肺受累的表现,早期诊断,积极治疗,将有助于显著改善患者的预后。

关键词：血管炎间质性肺疾病弥漫性肺泡出血结节肺动脉高压动脉瘤血栓

黑木耳多糖对梗阻性黄疸大鼠肝脏功能的保护作用

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中华中医药杂志 2014年第12期29卷 3985-3987页

作者：孙湛姚雪萍于文燕马琪马小娟新疆医科大学基础医学院乌鲁木齐830054

目的:探讨黑木耳多糖对梗阻性黄疸(oj)大鼠模型肝脏功能的保护作用。方法:48只健康雄性Wistar大鼠,随机抽取12只为假手术组,其余大鼠用胆总管结扎横断法制作大鼠梗阻性黄疸动物模型,将造模大鼠分为模型组及黑木耳多糖低、高剂量组(各12... 详细信息

目的:探讨黑木耳多糖对梗阻性黄疸(oj)大鼠模型肝脏功能的保护作用。方法:48只健康雄性Wistar大鼠,随机抽取12只为假手术组,其余大鼠用胆总管结扎横断法制作大鼠梗阻性黄疸动物模型,将造模大鼠分为模型组及黑木耳多糖低、高剂量组(各12只),分别给予0.9%氯化钠溶液及不同浓度黑木耳多糖灌胃干预7d。观察动物一般情况、下腔静脉采血检测血清胆红素、肝功能指标[谷丙转氨醇(ALT)、谷草转氨酶(AST)]、内毒素(ET)、肿瘤坏死因子(TNF-α)、白介素-6(IL-6)、取肝、小肠标本做病理分析。结果:应用黑木耳多糖干预后,大鼠的一般状态好于模型组,血清中胆红素、ALT、AST、ET、TNF-α、IL-6水平均显著低于模型组(P<0.05);肝、肠组织病理改变减轻。结论:黑木耳多糖通过抑制炎性介质释放、保护肠黏膜屏障对梗阻性黄疸大鼠肝脏有保护作用。

关键词：黑木耳多糖梗阻性黄疸肝功能肠黏膜屏障全身炎性反应