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Chinese Journal of Aeronautics 2023年第7期36卷 257-267页

作者： Yuqing mao Ping YANG Wenyan ZHANG ning LI Hao NIE Danyang LIN Liming KE National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology Nanchang Hangkong UniversityNanchang 330063China

To improve tensile-shear properties of fiction stir lap welded(FSLW) dissimilar Al/Mg joints, pin-tip profiles were innovatively designed and welding speed was optimized, and effects of them on formation, interface microstructure and mechanical properties of different FSLW joints were investigated. With increasing the welding speed, the tensile-shear load of FSLW joints produced by three pins presents an increasing firstly and then decreasing trend. Compared with Rpin, the hook and hole defect in the joints made by S-pin and T-pin are eliminated owing to additional eccentric force. Moreover, the joints obtained by T-pin at 75 mm/min have the highest tensile-shear load, and a maximum value of 3.425 kN is produced, which increases by 96.8%.Meanwhile, the pin-tip profile improves significantly the interface reaction depending on the welding temperature. For R-pin, thick brittle intermetallic compounds of about 6.9 μm Al3Mg2and 13.3 μm Al12Mg17layers at the welding interface derived from diffusion reaction are formed, resulting in continuous cracks. However, using T-pin can raise the interface temperature, and which makes the interface liquefy locally to generate only 2.2 μm Al3Mg2layer and dispersive(Al12-Mg17+Mg) eutectic structure. This can release high residual stress and remove welding crack, consequently enhancing the interface properties of T-pin joints.

关键词： Dissimilar Al/Mg alloys Friction stir lap welding Hook defect Interface microstructure Tensile-shear properties

口腔幽门螺杆菌与胃幽门螺杆菌相关性的研究进展

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湖北中医药大学学报 2024年第3期26卷 116-120页

作者：毛宁锋黄超群吕文亮湖北中医药大学中医临床学院湖北武汉430061 湖北省中医院湖北武汉430074

口腔是幽门螺杆菌(Hp)传播的必经关卡,也是除胃外的第二大定植地,口腔Hp可以影响胃内Hp的根除率以及复发率,在Hp的预防和治疗中至关重要。本文通过文献整理探讨口腔Hp与胃Hp之间的相互作用和影响,以期为临床防治Hp感染提供新的治疗思路。

关键词：幽门螺杆菌口腔幽门螺杆菌相关性综述

Research on Hydrodynamic Interference Suppression of Bottom-Mounted Monitoring Platform with Fairing Structure

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China Ocean Engineering 2018年第1期32卷 51-61页

作者： WANG Zhen ZHENG Yi mao Yu-feng WANG Ya-zhou YU Yan-ting LIU Hong-ning Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China Shandong Provincial Key Laboratory of Ocean Environmental Monitoring Technology Qingdao 266061China National Engineering and Technological Research Center of Marine Monitoring Equipment Qingdao 266061China

In the disturbance of unsteady flow field under the sea, the monitoring accuracy and precision of the bottom-mounted acoustic monitoring platform will decrease. In order to reduce the hydrodynamic interference, the platform wrapped with fairing structure and separated from the retrieval unit is described. The suppression effect evaluation based on the correlation theory of sound pressure and particle velocity for spherical wave in infinite homogeneous medium is proposed and the difference value between them is used to evaluate the hydrodynamic restraining performance of the bottom-mounted platform under far field condition. Through the sea test, it is indicated that the platform with sparse layers fairing structure(there are two layers for the fairing, in which the inside layer is 6-layers sparse metal net, and the outside layer is 1-layer polyester cloth, and then it takes sparse layers for short) has no attenuation in the sound pressure response to the sound source signal, but obvious suppression in the velocity response to the hydrodynamic noise. The effective frequency of the fairing structure is decreased below 10 Hz, and the noise magnitude is reduced by 10 d B. With the comparison of different fairing structures, it is concluded that the tighter fairing structure can enhance the performance of sound transmission and flow restraining.

关键词： bottom-mounted fairing hydrodynamic interference acoustic impedance transmission loss

Molten salt synthesis of Z-scheme CeO_(2)/C_(3)N_(4) photocatalysts with excellent properties for removal of organic pollutants:Characterization,kinetics and mechanisms

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Journal of Rare Earths 2023年第8期41卷 1153-1162,I0002页

作者： Deyang ning Junqi Li Yuanpei Lan Hong Yong Sohn Jian Yang Chaoyi Chen Zhiyao Chu Xisong mao Department of Metallurgical Engineering College of Materials and MetallurgyGuizhou UniversityGuiyang 550025China Guizhou Province Key Laboratory of Metallurgical Engineering and Process Energy Saving Guiyang 550025China Department of Materials Science&Engineering University of UtahSalt Lake CityUT84112USA College of Materials Science and Engineering Chongqing UniversityChongqing 40044China

In this work,we firstly synthesized a CeO_(2)/C_(3)N_(4) photocatalyst with Z-scheme heterojunction by a facile LiC-KCI molten salt *** synthesized catalyst has an excellent quality for removing organic pollution of dyes and antibiotics in *** an example,the CeCN-1:5 prepared with a mass ratio of Ce_(2)(CO_(3))_(3)·xH_(2)O:C_(3)H_(3)N_(6)=1:5 exhibits a methylene blue(MB)removal capacity of 100%within 90 min and tetracycline(TC)removal capacity of 94.6%.After 4 cycles,the CeCN-1:5 keeps a removal efficiency of nearly 100%in 150 min for MB and 85.7%for *** kinetics study reveals that the MB removal process with the CeCN-1:5 fits the modified Elovich model with strong adsorption while TC removal fits the first-order *** large surface area(238 m^(2)/g)and negative zeta potential(-39.3 mV)of CeCN-1:5 contribute to superior adsorption capacity to ***,the adsorption of TC is restricted due to the positive surface/pore potential in acidic ***-1:5has combined Z-scheme heterojunction and exhibits a low recombination rate of electrons(e^(-))/holes(h^(+))and the photo-generated active radicals of·OH/·O_(2)^(-)that promotes the photocatalytic *** novel CeO_(2)/C_(3)N_(4) photocatalyst with an excellent photocatalysis removal activity has an enormous potential for photocatalytic applications.

关键词： Molten salt synthesis CeO_(2)/C_(3)N_(4)composite Kinetic modeling Adsorption Photodegradation Rare earths

Protein tyrosine phosphatase 1B inhibitory activities of ursane-type triterpenes from Chinese raspberry, fruits of Rubus chingii

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Chinese Journal of Natural Medicines 2019年第1期17卷 15-21页

作者： ZHANG Xiang-Yu LI Wei WANG Jian LI ning CHENG mao-Sheng KOIKE Kazuo Key Laboratory of Structure-Based Drug Design&Discovery Ministry of EducationShenyang Pharmaceutical University School of Pharmaceutical Engineering Shenyang Pharmaceutical University Faculty of Pharmaceutical Sciences Toho University

Protein tyrosine phosphatase 1 B(PTP1 B) has led to an intense interest in developing its inhibitors as anti-diabetes, anti-obesity and anti-cancer agents. The fruits of Rubus chingii(Chinese raspberry) were used as a kind of dietary traditional Chinese medicine. The methanolic extract of R. chingii fruits exhibited significant PTP1 B inhibitory activity. Further bioactivity-guided fractionation resulted in the isolation of three PTP1 B inhibitory ursane-type triterpenes: ursolic acid(1), 2-oxopomolic acid(2), and 2α, 19α-dihydroxy-3-oxo-urs-12-en-28-oic acid(3). Kinetics analyses revealed that 1 was a non-competitive PTP1 B inhibitor, and 2 and 3 were mixed type PTP1 B inhibitors. Compounds 1-3 and structurally related triterpenes(4-8) were further analyzed the structure-activity relationship, and were evaluated the inhibitory selectivity against four homologous protein tyrosine phosphatases(TCPTP, VHR, SHP-1 and SHP-2). Molecular docking simulations were also carried out, and the result indicated that 1, 3-acetoxyurs-12-ene-28-oic acid(5), and pomolic acid-3β-acetate(6) bound at the allosteric site including α3, α6, and α7 helix of PTP1 B.

关键词： Protein tyrosine phosphatase 1B Raspberry Rubus chingii Triterpene Ursane

Separation-enrichment method for airborne disease spores based on microfluidic chip

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 199-205页

作者： Yafei Wang Xiaodong Zhang ning Yang Guoxin Ma Xiaoxue Du Hanping mao School ofAgricultural Engineering Jiangsu UniversitZhenjiang 212013JiansiChina Key Laboratory of Moderm Agricultural Equipment and Techmology Ministry of EducationJiangsu UniversitZhenjiang 212013JiangsuChina School of Electrical and Informnation Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Airborne diseases are likely to cause crop yield reduction,which has aroused widespread *** this study,a two-stage separation-enrichment structure microfluidic chip with a compound field for separation and enrichment of the greenhouse crops airborne disease spores directly from gas flow was *** chip is mainly composed of three parts:arc structure pretreatment channel,semicircular electrode structure and collection *** 5.1 software was used to simulate the designed microfluidic chip.30μm particles were used to represent *** spores,25μm particles were used to represent *** spores,and 16μm particles were used to represent *** *** simulation results showed that the separation and enrichment efficiency of 16μm particles,25μm particles,and 30μm particles was 88%,91%,and 94%,*** experimental verification results were observed under a *** results showed that the separation and enrichment efficiency of *** spores,*** spores and *** spores was 75.7%,83.8%and 89.4%,*** a result,the designed microfluidic chip can be used to separate and enrich the spores of airborne diseases of greenhouse crops,which can provide a basis for the research of real-time monitoring technology for greenhouse airborne diseases.

关键词： greenhouse crop disease airborne spore microfluidic chip

Subtle metastability of the layered magnetic topological insulator MnBi_(2)Te_(4) from weak interactions

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npj Computational Materials 2020年第1期6卷 362-367页

作者： Jinliang ning Yanglin Zhu Jamin Kidd Yingdong Guan Yu Wang Zhiqiang mao Jianwei Sun Department of Physics and Engineering Physics Tulane UniversityNew OrleansLA 70118USA Department of Physics The Pennsylvania State UniversityUniversity ParkPA 16802USA

Layered quantum materials can host interesting properties,including magnetic and topological,for which enormous computational predictions have been *** thermodynamic stability is much less visited computationally,which however determines the existence of materials and can be used to guide experimental ***_(2)Te_(4) is one of such layered quantum materials that was predicted to be an intrinsic antiferromagnetic topological insulator,and later experimentally realized but in a thermodynamically metastable state.

关键词： synthesis state topological

联合特征概率分布和时间相关性的无线网络业务建模方法

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航空电子技术 2024年第1期55卷 23-29页

作者：王智宇王宁李波杨懋闫中江航空电子综合与体系集成全国重点实验室上海200241 中国航空无线电电子研究所上海200241 西北工业大学西安710072

民用无线网络以及航空无线网络等未来无线网络需要承载需求多样化的业务类型和信息交互。数据包尺寸特征和数据包到达间隔等不同业务特征,对无线网络有至关重要的意义。然而,当前无线网络业务建模研究鲜有同时建模业务特征和业务特征的... 详细信息

民用无线网络以及航空无线网络等未来无线网络需要承载需求多样化的业务类型和信息交互。数据包尺寸特征和数据包到达间隔等不同业务特征,对无线网络有至关重要的意义。然而,当前无线网络业务建模研究鲜有同时建模业务特征和业务特征的时间相关性,这导致对业务的建模刻画不够准确。本文提出一种联合业务特征概率分布和时间相关性的无线网络业务建模方法,保障了业务特征的概率分布和业务特征的时间相关性。本方法具有一般性,可以应用于民用无线网络的业务建模,也可以应用到航空无线领域,有利于对业务特性的把握,从而进行更加优化和确定性的资源分配。

关键词：业务建模时间相关性无线网络无线局域网

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多旋翼无人机增稳云台的优化设计

机械制造 2024年第1期62卷 1-6页

作者：毛书斌李宁王澈凌晨伟程帅栗浩齐台州学院智能制造学院浙江台州318000

针对现有无人机增稳云台在通用性、结构稳定性等方面存在的问题,优化设计了一种能够兼容大多数无人机的多旋翼无人机增稳云台。对现有无人机增稳云台的两种典型结构进行ANSYS软件仿真分析,通过改变减振球数量、分布位置和减振板外形,来... 详细信息

针对现有无人机增稳云台在通用性、结构稳定性等方面存在的问题,优化设计了一种能够兼容大多数无人机的多旋翼无人机增稳云台。对现有无人机增稳云台的两种典型结构进行ANSYS软件仿真分析,通过改变减振球数量、分布位置和减振板外形,来进行优化设计,得到多旋翼无人机增稳云台。在ANSYS软件中对优化设计的多旋翼无人机增稳云台进行静力学与预应力模态分析,数据表明强度、刚度符合要求,并且具有良好的动态性能。

关键词：无人机增稳云台设计优化

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浙西南高山樱桃番茄新优品种筛选

长江蔬菜 2024年第20期 39-42页

作者：章宁张世法毛月旺兰树珍龙泉市农业农村局经济作物服务站浙江丽水323700 龙泉市云田农业有限责任公司龙泉市蔬菜瓜果产业协会

为筛选出适合浙西南高山地区设施栽培的优质高产樱桃番茄品种,特引进13个樱桃番茄品种开展比较试验,以黄妃樱桃番茄为对照(CK),比较各品种的抗病性、果实性状、风味、产量等综合指标。结果表明,13个参试品种中,紫千禧、粉多美、黄宝珠... 详细信息

为筛选出适合浙西南高山地区设施栽培的优质高产樱桃番茄品种,特引进13个樱桃番茄品种开展比较试验,以黄妃樱桃番茄为对照(CK),比较各品种的抗病性、果实性状、风味、产量等综合指标。结果表明,13个参试品种中,紫千禧、粉多美、黄宝珠的综合性状最好,产量高,抗病强,口感及商品性好,可作为主栽品种进行推广,以满足市场不同需求。

关键词：樱桃番茄抗病性果实性状产量