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Journal of Advanced Ceramics 2024年第5期13卷 590-601页

作者： Hui Chen Yulei Zhang Yanqin Fu Wenhan Gai junhao zhao Haohui Zhang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China

Ultra-high-temperature ceramic nanowires have shown increasing potential for use as thermal structural ***,novel single-crystal Hf_(0.5)Ta_(0.5)C solid solution nanowires were synthesized and incorporated with a HfC coating to construct a robust structure with Hf_(0.5)Ta_(0.5)C solid solution nanowires uniformly distributed and interconnected within the *** novel Hf_(0.5)Ta_(0.5)C solid solution nanowires could effectively hinder crack propagation through crack tip pinning and crack *** mechanism substantially enhanced the elastic modulus and fracture toughness of the HfC coating by 53.29%and 59.67%,*** toughened HfC coating displayed superior fracture toughness and good interfacial binding strength with the substrate to resist severe oxidation and ***,the high thermal conductivity of the toughened HfC coating promoted heat ***,in comparison to the pure HfC coating,the toughened HfC coating displayed smaller mass and linear ablation rates of−0.35 mg·s^(−1)and−0.46μm·s^(−1),which decreased by 39.66%and 36.98%,*** work not only simultaneously enhances the mechanical properties and ablation resistance of HfC-coated carbon/carbon(C/C)composites but also provides novel prospects for advanced ultrahigh-temperature ceramic nanowires under extreme conditions.

关键词： Hf_(x)Ta_(1−x)C solid solution nanowires HfC coating carbon/carbon(C/C)composites mechanical performance ablationresistance

Superior synergistic oxidation resistance of medium-entropy carbide ceramic powders rather than multi-phase carbide ceramic powders

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Journal of Advanced Ceramics 2024年第8期13卷 1223-1233页

作者： Jiachen Li Fanyu Lu Tao Li Yanqin Fu junhao zhao Junshuai Lv Yulei Zhang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi'an 710072China

To date,some questions about medium-entropy carbide ceramics and the corresponding multi-phase carbide ceramics with the same cations and proportions remain *** oxidation behavior,do both have synergistic oxidation abilities and what role does entropy stabilization play in medium-entropy carbides?In this work,the oxidation behaviors of HfC-ZrC-TiC multi-phase carbide(HZT-MPC)and(Hf_(1/3)Zr_(1/3)Ti_(1/3))C medium-entropy carbide(HZT-MEC)powders were *** thermogravimetry(TG)oxidation,the TG curve of HZT-MPC had a bimodal ***"preferential oxidation"of HfC/ZrC occurred within HZT-MPC,followed by the formation of multi-phase oxides(HfO_(2),ZrO_(2),and TiO_(2)).The uneven compositional distribution slowed their solid solution reactions to form Ti-doped(Hf,Zr)O_(2) and(Hf,Zr)TiO_(4).The TG curve of HZT-MEC had a single peak.A uniform compositional distribution at the atomic scale promoted the rapid interdiffusion of oxides,forming Ti-doped(Hf,Zr)O_(2) and(Hf,Zr)TiO_(4) without ZrO_(2),HfO_(2),and TiO_(2) after TG ***,HZT-MEC had a higher onset oxidation temperature(To;470℃)than did HZT-MPC(430℃),and the TG single peak of HZT-MEC was between the TG bimodal peaks of ***,HZT-MEC showed superior oxidation resistance compared to HZT-MPC,which was attributed to the entropy stabilization effect of HZT-MEC suppressing the"preferential oxidation"of HfC/ZrC and the"delayed oxidation"of TiC,promoting the synergistic oxidation ability of multiple principal elements.

关键词： medium-entropy carbide multi-phase carbide synergistic oxidation ability oxidation resistance

Single-source precursor derived high-entropy metal–carbide nanowires:Microstructure and growth evolution

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Journal of Advanced Ceramics 2023年第11期12卷 2041-2052页

作者： junhao zhao Yulei Zhang Hui Chen Yanqin Fu Qing Miao Jiachen Meng Jiachen Li Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China

In recent years,high-entropy metal carbides(HECs)have attracted significant attention due to their exceptional physical and chemical *** combination of excellent performance exhibited by bulk HEC ceramics and distinctive geometric characteristics has paved the way for the emergence of one-dimensional(1D)HECs as novel materials with unique development ***,we successfully fabricated novel(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires derived via Fe-assisted single-sourced precursor *** to the synthesis of the nanowires,the composition and microstructure of(Ti,Zr,Hf,Nb,Ta)-containing precursor(PHECs)were analyzed,and divinylbenzene(DVB)was used to accelerate the conversion process of the precursor and contribute to the formation of HECs,which also provided a partial carbon source for the nanowire ***,multi-branched,single-branched,and single-branched bending nanowires were synthesized by adjusting the ratio of PHECs to *** obtained single-branched(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires possessed smooth surfaces with an average diameter of 130–150 nm and a length of several tens of micrometers,which were a single-crystal structure and typically grew along the[11¯1]***,the growth of the(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires was in agreement with top-type vapor–liquid–solid *** work not only successfully achieved the fabrication of HEC nanowires by a catalyst-assisted polymer pyrolysis,but also provided a comprehensive analysis of the factors affecting their yield and morphology,highlighting the potential application of these attractive nano-materials.

关键词： (Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires high-entropy metal carbides(HECs) (Ti,Zr,Hf,Nb,Ta)-containing precursors vapor–liquid–solid(VLS)mechanism

Long-Lasting Filtration of Oily Water by Anti-Fouling Underwater Oleophobic Sand Particles

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Journal of Bionic Engineering 2024年第2期21卷 913-923页

作者： Xingyu Liu Junxu Chen Rui Wang Yifan Su Zhangheng Zhou Zezhong Hou Zhuoran Li junhao zhao Weicai Shi Xinquan Yu zhaopeng Yu Youfa Zhang State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu233000China Jiangsu Key Laboratory of Advanced Metallic Materials School of Materials Science and EngineeringSoutheast UniversityNanjing211189China Research Institute of Petroleum Engineering Technology of Jiangsu Oilfield Yangzhou225009China Kunshan Industrial Technology Research Institute Kunshan215300SuzhouChina School of Automotive Engineering Changshu Institute of TechnologyChangshu215500SuzhouChina

The produced water from the oilfield was purified with filter material and then injected back into the *** serpentine filter material was easy to harden with the increase in filtration amount,which affected the water quality.A superhydrophilic/underwater oleophobic serpentine filter material was successfully prepared by a simple method of coating modification,which exhibited long-lasting filtration of oily water,good filtration and anti-fouling properties,and resistance to *** film-forming material of the superhydrophilic/underwater oleophobic coating was composed of SiO_(2) particles with small size,which could completely and evenly cover the filter *** weight loss was only 7.6%after mechanical stirring for 90 *** with the original filter material,the superhydrophilic/underwater oleophobic serpentine filter material showed a better anti-fouling ability and resistance to *** filtration of crude oil emulsion and oil slick sewage showed a better backwashing *** 35 cycles of continuous filtration of suspended solids in wastewater,the backwashing rate reached 78.4%.The results provided an effective method for the filtration of oily wastewater in the oilfield.

关键词： Serpentine Underwater oleophobic Water immersion resistance Anti-fouling Hardening resistance

An improved long-term correlation tracking method with occlusion handling

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Chinese Optics Letters 2019年第3期17卷 36-41页

作者： junhao zhao Gang Xiao Xingchen Zhang D· P· Bavirisetti School of Aeronautics and Astronautics Shanghai Jiao Tong University

By improving the long-term correlation tracking(LCT) algorithm, an effective object tracking method, improved LCT(ILCT), is proposed to address the issue of occlusion. If the object is judged being occluded by the designed criterion, which is based on the characteristic of response value curve, an added re-detector will perform re-detection, and the tracker is ordered to stop. Besides, a filtering and adoption strategy of re-detection results is given to choose the most reliable one for the re-initialization of the tracker. Extensive experiments are carried out under the conditions of occlusion, and the results demonstrate that ILCT outperforms some state-of-the-art methods in terms of accuracy and robustness.

关键词： improved long-term correlation tracking method occlusion handling

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Adverse Effects of Inactivated Foot-and-Mouth Disease Vaccine—Possible Causes Analysis and Countermeasures

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World Journal of Vaccines 2018年第4期8卷 81-88页

作者： Keshan Zhang Bingzhou Lu Huanan Liu junhao zhao Haixue Zheng Xiangtao Liu State Key Laboratory of Veterinary Etiological Biology National Foot and Mouth Disease Reference Laboratory Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Lanzhou China

Foot-and-mouth disease (FMD) is an infectious and sometimes fatal viral disease that affects cloven-hoofed animals, and Chinese government adopts compulsory immunization measures for FMD. The adverse effects of FMD vaccine to pigs, cattle and goats have been reported increasingly frequent during the spring and autumn seasons when large numbers of farm livestock are vaccinated. The financial losses caused by vaccine adverse effects have been a serious concern for both farmers and primary prevention personnel. There are various causative factors reported to involve into adverse effect of FMD vaccine, including the inappropriate vaccine production, transportation and storage, livestock poor tolerance, and unqualified vaccinating manipulations. Symptomatic treatment and early drug prevention have a certain effect on the adverse effects. To analyze causes and propose countermeasures, in the current study possible reasons during the production and processing procedures of inactivated FMD vaccine were reviewed and corresponding countermeasures were recommended. The review may provide references for better use of vaccine to prevent FMD.

关键词： Foot-and-Mouth Disease Inactivated Vaccine Adverse Effects Causes Analysis and Countermeasures

基于改进MVCNN的IFC构件分类识别审查方法

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湖南大学学报（自然科学版） 2023年第11期50卷 216-223页

作者：王茹胡芸浩黄炜赵俊浩西安建筑科技大学土木工程学院陕西西安710055 结构工程与抗震教育部重点实验室陕西西安710055

为实现IFC构件精确、高效分类,提出一种改进的多视图卷积神经网络(Multiview Convolutional Neural Network,MVCNN)模型,该模型引入了自注意力模块和长短期记忆(LongShort-termMemory,LSTM)网络,针对MVCNN模型特征融合的局限性,设计了LS... 详细信息

为实现IFC构件精确、高效分类,提出一种改进的多视图卷积神经网络(Multiview Convolutional Neural Network,MVCNN)模型,该模型引入了自注意力模块和长短期记忆(LongShort-termMemory,LSTM)网络,针对MVCNN模型特征融合的局限性,设计了LSTM_ATT模块;通过对各视图数据特征关系的自适应调整,并结合注意力权重对输入的各视图数据进行融合,得到一个更具辨识性的3D形状描述符,从而提高模型对各相似IFC构件的分类检测性能.使用IFCNet数据集对建筑领域20个主要类别的IFC构件进行训练并在测试集上对改进MVCNN模型与MVCNN模型进行实验对比.实验结果表明,改进模型的分类准确率和F1值分别达到了88.27%、86.72%,相比改进前准确率提高了9.46%,对相似构件之间的分类识别效果明显.

关键词： IFC构件分类识别多视图卷积神经网络深度学习审查

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中国经济发展方式转变指标体系的构建与测度

统计与决策 2017年第23期33卷 36-39页

作者：邹一南赵俊豪中共中央党校经济学教研部北京100091 中共中央党校研究生院北京100091

文章在分析了经济发展方式转变内涵的基础上,从创新发展、协调发展、绿色发展、开放发展、共享发展五个方面,构建了中国经济发展方式转变的指标体系,并综合利用德尔菲法和熵值法,对"十一五"至"十二五"期间经济发展方式的转变程度进行测算。

关键词：发展方式转变指标体系熵值法

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基于循环提取有效信息的主轴承故障特征增强方法

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仪器仪表学报 2024年第3期45卷 251-262页

作者：栾孝驰赵俊豪沙云东佟鑫宇张振鹏沈阳航空航天大学航空发动机学院辽宁省航空推进系统先进测试技术重点实验室沈阳110136

针对航空发动机主轴承发生故障时特征信息提取不充分的问题,提出一种基于循环提取有效信息的主轴承故障特征增强方法。该方法首先对原始振动信号进行小波包分解,计算得到各个节点分量的相关系数值和峭度值,将其进行归一化融合为一个综... 详细信息

针对航空发动机主轴承发生故障时特征信息提取不充分的问题,提出一种基于循环提取有效信息的主轴承故障特征增强方法。该方法首先对原始振动信号进行小波包分解,计算得到各个节点分量的相关系数值和峭度值,将其进行归一化融合为一个综合参数P i;其次根据特征信息循环提取准则定义一个置信区间,该区间将所有节点分量划分为高信噪比信号、低信噪比信号和高噪信号3个部分;然后不断筛选出高信噪比信号直至达到终止条件;最后重构所有高信噪比信号,并进行包络解调提取出轴承微弱故障特征。经仿真信号验证,去噪信号的信噪比相对于去噪前提升了11.31 dB。基于航空发动机中介轴承模拟试验台所测数据开展了特征信息循环提取方法有效性的综合验证,并对某型航空发动机主轴承振动信号进行了分析。实践表明:该方法适用于强背景噪声干扰工况下滚动轴承的特征提取,能准确诊断航空发动机主轴承故障。

关键词：滚动轴承航空发动机小波包分解特征信息循环提取准则故障特征增强

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社会主义新时代高职院校体育工作的重难点

湖北水利水电职业技术学院学报 2019年第4期 26-30页

作者：赵俊浩湖北水利水电职业技术学院湖北武汉430070

文章重点论述了社会主义新时代高职院校体育工作的重难点,结合新时代的特点展开深层次剖析,找出高职体育教育的不足及问题,并相应地提出解决建议及对策。

关键词：社会主义新时代高职院校体育重难点建议及对策