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成人女性拔牙正畸治疗后软硬组织变化的三维研究

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口腔医学研究 2024年第4期40卷 337-342页

作者：陈晓波余诚诚朱紫茹何洁厦门医学院附属口腔医院正畸科厦门市口腔疾病诊疗重点实验室福建厦门361008 厦门医学院福建厦门361023

目的:回顾性研究成年女性拔牙正畸治疗后软硬组织三维方向的改变,并分析其相关性以提供临床决策的循证证据。方法:本研究共纳入40例女性患者,用Dolphin软件对正畸治疗前后的锥形束断层扫描(cone-beam computed tomography,CBCT)数据进... 详细信息

目的:回顾性研究成年女性拔牙正畸治疗后软硬组织三维方向的改变,并分析其相关性以提供临床决策的循证证据。方法:本研究共纳入40例女性患者,用Dolphin软件对正畸治疗前后的锥形束断层扫描(cone-beam computed tomography,CBCT)数据进行定量分析。结果:上下唇以及鼻唇沟区软组织治疗前后在矢状向差异均有统计学意义,鼻唇沟区(nasolabial folds,NLF)软组织从上往下变化量逐渐增大(NFL3>NLF2>NFL1),从内往外逐渐减小(L2>NLF2>L1)。切牙内收量与唇组织变化之间存在中度正相关(r=0.52),上尖牙内收量与鼻唇沟区软组织变化之间也存在中度正相关(r=0.63)。结论:成年女性拔牙正畸治疗可以有效改善凸面型和唇形态,其切牙和尖牙内收量可用于预测唇及鼻唇沟区软组织矢状向的改变。尽管鼻唇沟区软组织发生了负向改变,但鼻唇沟皱褶是否会加深仍需进一步研究。

关键词：拔牙锥形束断层扫描鼻唇沟软组织正畸

Engineering three-layer core–shell S-1/TS-1@dendritic-SiO_(2) supported Au catalysts towards improved performance for propene epoxidation with H_(2) and O_(2)

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Green Energy & Environment 2020年第4期5卷 473-483页

作者： Zhaoning Song Juncong Yuan Zhenping Cai Dong Lin Xiang Feng Nan Sheng Yibin Liu xiaobo chen Xin Jin De chen Chaohe Yang State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao266580China Department of Chemical Engineering Norwegian University of Science and TechnologyTrondheim7491Norway State Key Laboratory of Safety and Control for Chemicals SINOPEC Qingdao Research Institute of Safety Engineering218 Yanansan RoadQingdao266580China

The advocacy of green chemical industry has led to the development of highly efficient catalysts for direct gas-phase propene epoxidation with green,sustainable and simple essence.The S-1/TS-1@dendritic-SiO_(2) material with three-layer core–shell structure was developed and used as the support for Au catalysts,which showed simultaneously fantastic PO formation rate,PO selectivity and stability(over 100 h)for propene epoxidation with H_(2) and O_(2).It is found that silicalite-1(S-1)core and the middle thin layer of TS-1 offer great mass transfer ability,which could be responsible for the excellent stability.The designed dendritic SiO_(2) shell covers part of the acid sites on the external surface of TS-1,inhibiting the side reactions and improving the PO selectivity.Furthermore,three kinds of SiO_(2) shell morphologies(i.e.,dendritic,net,mesoporous shell)were designed,and relationship between shell morphology and catalytic performance was elucidated.The results in this paper harbour tremendous guiding significance for the design of highly efficient epoxidation catalysts.

关键词： Propene epoxidation Selectivity Core-shell Dendritic SiO_(2)shell TS-1

Microwave absorption of aluminum/hydrogen treated titanium dioxide nanoparticles

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Journal of Materiomics 2019年第1期5卷 133-146页

作者： Michael Green Peng Xiang Zhanqiang Liu James Murowchick Xinyu Tan Fuqiang Huang xiaobo chen Department of Chemistry University of MissourieKansas CityKansas CityMO64110USA College of Materials and Chemical Engineering Hubei Provincial Collaborative Innovation Center for New Energy MicrogridChina Three Gorges UniversityYichang443002China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Department of Geosciences University of MissourieKansas CityKansas CityMO64110USA State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

Interactions between incident electromagnetic energy and matter are of critical importance for numerous civil and military applications such as photocatalysis,solar cells,optics,radar detection,communications,information processing and transport et al.Traditional mechanisms for such interactions in the microwave frequency mainly rely on dipole rotations and magnetic domain resonance.In this study,we present the first report of the microwave absorption of Al/H2 treated TiO_(2) nanoparticles,where the A_(l)/H_(2) treatment not only induces structural and optical property changes,but also largely improves the microwave absorption performance of TiO_(2) nanoparticles.Moreover,the frequency of the microwave absorption can be finely controlled with the treatment temperature,and the absorption efficiency can reach optimal values with a careful temperature tuning.A large reflection loss of58.02 dB has been demonstrated with 3.1mm TiO_(2) coating when the treating temperature is 700℃.The high efficiency of microwave absorption is most likely linked to the disordering-induced property changes in the materials.Along with the increased microwave absorption properties are largely increased visiblelight and IR absorptions,and enhanced electrical conductivity and reduced skin-depth,which is likely related to the interfacial defects within the TiO_(2) nanoparticles caused by the Al/H2 treatment.

关键词： Microwave absorption Black TiO_(2)nanoparticles Hydrogenation Aluminum reduction

A “protector” model for membrane trafficking-regulated and NLR-mediated plant immunity

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Molecular Plant 2023年第2期16卷 303-305页

作者： xiaobo Zhu Xuewei chen State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Sichuan Agricultural University at WenjiangChengduSichuan 611130China

Plants are constantly exposed to a vast diversity of micro-organisms.They have accordingly evolved a sophisticated innate immunity system,mainly consisting of pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)(Jones and Dangl,2006)to combat microbial pathogens.Pattern-recognition receptors(PRRs)on the cell membrane sense immunogenic molecular patterns derived from microbes(pathogen-associated molecular patterns,PAMPs)and the host itself(damage-associated molecular patterns,DAMPs)to activate PTI(Zhou and Zhang,2020;Zhao et al.,2022).

关键词： immunity damage pattern

基于遗传算法的集中式传动系统齿轮修形及模态优化研究

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工程设计学报 2024年第3期31卷 340-347页

作者：余晓波陈素姣章勇华马彬隽柳工柳州传动件有限公司传动件研究所广西柳州545007 广西柳工机械股份有限公司广西柳州545007

集中式传动系统布局紧凑,部件间距小,因此对其NVH(noise,vibration,harshness,噪声、振动与声振粗糙度)控制提出了更高要求。以某工程机械的集中式传动系统为研究对象,首先,进行了其振动噪声测试,并分析了齿轮微观修形原理;其次,考虑了... 详细信息

集中式传动系统布局紧凑,部件间距小,因此对其NVH(noise,vibration,harshness,噪声、振动与声振粗糙度)控制提出了更高要求。以某工程机械的集中式传动系统为研究对象,首先,进行了其振动噪声测试,并分析了齿轮微观修形原理;其次,考虑了系统模态共振与齿轮啮合的相互耦合,建立了该传动系统的有限元模型并进行仿真,结果显示,齿轮副接触斑点和模态的仿真结果与测试结果一致,验证了建模方法的可行性;接着,基于遗传算法求解了齿轮微观修形参数,实现了齿轮微观修形的最优设计,并通过模态优化来避免系统共振;最后,进行实验验证,结果表明,齿轮修形后传动系统的噪声降低至95.2 dB,比修形前下降了4.8 dB。采用基于遗传算法的齿轮微观修形和模态优化方法可以降低传动系统的振动噪声,这为集中式传动系统的NVH控制提供了一定参考。

关键词：传动系统遗传算法微观修形模态分析传递误差

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触发闪电环境下地网冲击接地电阻特征分析

热带气象学报 2024年第2期40卷 208-216页

作者：张鹃王孝波颜旭陈绍东中山大学大气科学学院广东珠海519082 江门市气象局广东江门529030 广州市气象局广东广州511430 中国气象局广州热带海洋气象研究所广东广州510641

基于触发闪电技术,研究了2019年夏季8次触发闪电44次回击、5次初始连续电流脉冲(ICCP)和24次M分量对冲击接地电阻的影响,探索了冲击接地电阻随雷电流注入的动态变化规律。结果发现:闪电放电ICCP、M分量和回击过程冲击接地电阻均小于工... 详细信息

基于触发闪电技术,研究了2019年夏季8次触发闪电44次回击、5次初始连续电流脉冲(ICCP)和24次M分量对冲击接地电阻的影响,探索了冲击接地电阻随雷电流注入的动态变化规律。结果发现:闪电放电ICCP、M分量和回击过程冲击接地电阻均小于工频接地电阻,ICCP和叠加在回击回落之后连续电流上的M分量冲击接地电阻略大于回击过程,平均值分别为11.2Ω和10.8Ω。叠加在回击下降沿上的M分量冲击接地电阻平均值7.8Ω,明显小于回击过程,最小值可达2.4Ω。ICCP和M分量冲击接地电阻随电流增加而减小,回击过程与电流峰值没有明显的相关性。叠加在回击下降沿上的M分量冲击接地电阻随雷电流峰值、背景电流值的增加呈指数衰减关系,还与之前回击电流峰值成一定的反比例关系。随着闪电回击电流的注入,冲击接地电阻呈现动态变化过程,小电流在回击峰值下降后出现一个缓慢增长的过程,大电流在回击峰值下降后出现一个快速下降的过程。闪电不同物理过程火花和电感效应的作用是不同的,两者共同作用决定了土壤的电离程度,从而决定了冲击接地电阻的大小和变化。

关键词：人工触发闪电回击初始连续电流脉冲 M分量冲击接地电阻

核电厂二回路金属管道流动加速腐蚀与防护的研究进展

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腐蚀与防护 2024年第2期45卷 10-17页

作者：乔睿鑫董亮陈建栋邱晓波常州大学江苏省油气储运技术重点实验室常州213164 青岛雅合科技发展有限公司青岛266000 无锡纽思铁科能源科技有限公司无锡214187

综述了核电厂二回路管线的流动加速腐蚀研究现状。介绍了流体动力学因素、环境因素、材料因素对流动加速腐蚀的影响机理及规律,总结了流动加速腐蚀常用的研究方法和防护措施,最后对存在的问题及未来研究的方向进行了探讨。

关键词：流动加速腐蚀影响因素研究方法防护措施

New design principles for the bath towards chromate-and crack-free conversion coatings on magnesium alloys

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Journal of Magnesium and Alloys 2021年第2期9卷 505-519页

作者： Shangju Liao Baoxing Yu Xuliang Zhang Xiaopeng Lu Peng Zhou Chunyan Zhang xiaobo chen Tao Zhang Fuhui Wang Corrosion and Protection Division Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences62 Wencui RdShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Shenyang National Laboratory for Materials Science Northeastern University3-11 Wenhua RdShenyang 110819China Shanghai Spaceflight Precision Machinery Research Institute No.76 Guide RoadSongjiangShanghai 201600China School of Engineering RMIT UniversityCarltonVIC 3053Australia

Cracking and low thickness are major obstacles to the high corrosion performance of conversion coating on magnesium alloy.In this work,the ratio of total acidity to p H(TA/p H)was applied as an indicator,and new principles regarding the design of conversion bath were proposed.The treatment bath should be composed of species that can be categorized into two groups:the first group of species that react with Mg substrate to increase the local p H at the interface;the second group that precipitate and contributes to the growth of coating.The species belong to second group exists in a supersaturated state and its precipitation process is almost independent on the reactions of the species in first group.By this way,a thick and crack-free two-layered conversion coating is obtained.Moreover,the nature of the adjustment of TA/p H and the roles of the oxidizing agent and catalyst were discussed.

关键词： Phosphate conversion coating Design principles Magnesium alloy TA/pH Corrosion resistance

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炉压对齿轮离子渗氮的影响

金属热处理 2024年第6期49卷 129-134页

作者：李双喜沈亚秋白小波高洁陈琳河南机电职业学院北京首航科学技术开发有限公司信阳分公司中铁工程装备集团有限公司

向离子渗氮炉内通入氨气和氩气，保持氨气流量为0.5 L/min,通过改变氩气流量来控制炉压(氩气流量分别为0、0.45、0.60、0.85 L/min),研究炉压对小模数齿轮渗氮层均匀性和渗氮层组织的影响。结果表明，离子渗氮层均匀性随着氩气通入量的... 详细信息

向离子渗氮炉内通入氨气和氩气，保持氨气流量为0.5 L/min,通过改变氩气流量来控制炉压(氩气流量分别为0、0.45、0.60、0.85 L/min),研究炉压对小模数齿轮渗氮层均匀性和渗氮层组织的影响。结果表明，离子渗氮层均匀性随着氩气通入量的增加而增加；在540℃×8 h离子渗氮工艺下，当炉压低于180 Pa时，轮齿齿根处无法渗氮；当炉压高于330 Pa时，炉内由于辉光厚度太薄，打弧几率增加，炉温均匀性变差。随着氩气通入量的增加，化合物层厚度减少，并在一定程度上提高渗氮速率，而对渗层疏松和脉状氮化物级别无明显影响。

关键词：离子渗氮齿轮辉光厚度炉压