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滚动轴承表面损伤故障智能诊断新方法

仪器仪表学报 2009年第1期30卷 44-49页

作者：陈果南京航空航天大学民航学院南京210016

本文针对目前基于小波变换的滚动轴承故障诊断研究中普遍存在小波变换参数选取和故障特征计算无法自动完成的问题,提出了一种基于小波包变换的滚动轴承故障特征自动提取技术,实现了小波函数参数的自动选取和故障特征的自动提取。最后,... 详细信息

本文针对目前基于小波变换的滚动轴承故障诊断研究中普遍存在小波变换参数选取和故障特征计算无法自动完成的问题,提出了一种基于小波包变换的滚动轴承故障特征自动提取技术,实现了小波函数参数的自动选取和故障特征的自动提取。最后,基于结构自适应神经网络方法建立了滚动轴承的集成神经网络智能诊断模型,利用实际的滚动轴承实验数据进行了验证,结果表明了本文方法的有效性。

关键词：滚动轴承小波包变换神经网络特征提取智能诊断

Cold sintering process for fabrication of a superhydrophobic ZnO-polytetrafluoroethylene(PTFE)ceramic composite

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Journal of Advanced Ceramics 2023年第9期12卷 1758-1766页

作者： Xuetong Zhao Yang Yang Li Cheng Jing guo Shenglin Kang Yuchen Li Xilin Wang Lijun Yang Ruijin Liao State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400044China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

Composite coatings or films with polytetrafluoroethylene(PTFE)are typically utilized to offer superhydrophobic ***,the superhydrophobic surfaces usually have limited durability and require complicated fabrication ***,we report the successful integration of PTFE with ZnO ceramics to achieve superhydrophobicity via a one-step sintering method,cold sintering process(CSP),at 300℃.(1–x)ZnO–x PTFE ceramic composites with x ranging from 0 to 70 vol%are densified with relative density of over 97%.Micro/nano-scale PTFE polymer is dispersed among ZnO grains forming polymer grain boundary phases,which modulate surface morphology and surface energy of the ZnO–PTFE ceramic *** the 60 vol%ZnO–40 vol%PTFE ceramic composite,superhydrophobic properties are optimized with static water contact angles(WCAs)and sliding angles(SAs)of 162°and 7°,*** abrading into various thicknesses(2.52,2.26,and 1.99 mm)and contaminating with graphite powders on the surface,WCA and SA are still maintained with a high level of 157°–160°and 7°–9.3°,*** work indicates that CSP provides a promising pathway to integrate polymers with ceramics to realize stable superhydrophobicity.

关键词： cold sintering process(CSP) ZnO-polytetrafluoroethylene(PTFE)ceramic composites contact angles sliding angles(SAs) superhydrophobicity

基于小波分析的转子故障信号自适应降噪技术研究

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航空动力学报 2008年第1期23卷 9-16页

作者：陈果南京航空航天大学民航学院南京210016

在转子故障信号的小波降噪研究中,降噪效果常常依赖小波分解层数、故障转子转速和信号的采样频率,难于自动完成.针对该问题,提出了一种转子故障信号的自适应小波降噪新方法,该方法先对原始数据进行重采样,然后将重采样信号用小波变换分... 详细信息

在转子故障信号的小波降噪研究中,降噪效果常常依赖小波分解层数、故障转子转速和信号的采样频率,难于自动完成.针对该问题,提出了一种转子故障信号的自适应小波降噪新方法,该方法先对原始数据进行重采样,然后将重采样信号用小波变换分解到规定的层数,最后运用Donoho软阈值法实现降噪.该方法无需人为选取小波分解层数,降噪过程自动完成.大量的仿真和实验算例验证了方法的正确有效性.

关键词：航空航天推进系统小波分析降噪转子故障诊断

The phage T4 DNA ligase mediates bacterial chromosome DSBs repair as single component non-homologous end joining

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Synthetic and Systems Biotechnology 2019年第2期4卷 107-112页

作者： Tianyuan Su Fapeng Liu Yizhao Chang Qi guo Junshu Wang Qian Wang Qingsheng Qi State Key Laboratory of Microbial Technology Shandong UniversityQingdao266237People's Republic of China National Glycoengineering Center Shandong UniversityQingdao266237People's Republic of China CAS Key Lab of Biobased Materials Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao266101People's Republic of China

DNA double-strand breaks(DSBs)are one of the most lethal forms of DNA damage that is not efficiently repaired in *** microorganisms can handle chromosomal DSBs using the error-prone non-homologous end joining(NHEJ)system and ultimately cause genome ***,we demonstrated that Enterobacteria phage T4 DNA ligase alone is capable of mediating in vivo chromosome DSBs repair in Escherichia *** ligation efficiency of DSBs with T4 DNA ligase is one order of magnitude higher than the NHEJ system from Mycobacterium *** process introduces chromosome DNA excision with different sizes,which can be manipulated by regulating the activity of host-exonuclease *** DNA deletion length reduced either by inactivating recB or expressing the RecBCD inhibitor Gam protein fromλ***,we also found single nucleotide substitutions at the DNA junction,suggesting that T4 DNA ligase,as a single component non-homologous end joining system,has great potential in genome mutagenesis,genome reduction and genome editing.

关键词： T4 DNA ligase DNA double-strand breaks Non-homologous end joining CRISPR-Cas9

Interruption of bile acid enterohepatic circulation inhibits glycogen synthesis and promotes hepatocellular carcinoma progression

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Genes & Diseases 2023年第6期10卷 2218-2221页

作者： Jiyan Wang Xintong Dai Hongkai Chang Qingle Gao Jianshuang guo Juze Yang Shuai Zhang Changliang Shan State Key Laboratory of Medicinal Chemical Biology College of Pharmacy and Tianjin Key Laboratory of Molecular Drug ResearchNankai UniversityTianjin 300350China Department of Respiratory Medicine Sir Run Run Shaw Hospital and Institute of Translational MedicineZhejiang University School of MedicineHangzhouZhejiang 310016China School of Integrative Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China

In recent years,increasing attention has been given to public *** and obesity are hot topics,in which glucose and lipid metabolism play an important *** synthase GYS2 has been found to regulate glycogen metabolism in hepatocellular carcinoma(HcC)and is a potential prognostic factor and therapeutic target.i Excessive bile acids induce intestinal injury and inflammatory bowel disease,and targeting bile acid receptors(FXRs)can regulate inflammation and repair damaged intestinal epithelial barriers.2 However,the research model of metabolic pathways focuses on the key enzymes,while ignoring the overall ***,we targeted the glycogen anabolism pathway and screened the upstream factor,bile acid transporter ***10A1 participates in the enterohepatic circulation of bile acids and regulates the transcriptional activity of the bile acid receptor ***,we found that diazinon could bind NTCP and inhibit glycogen synthesis by mimicking the disordered bile acid enterohepatic ***,enterohepatic circulation of bile acids coordinates lipid metabolism and glucose metabolism and draws the metabolic crosstalk network,which provides a new perspective for the clinical treatment of HCC.

关键词： metabolism bile hepatic

In-situ controllable synthesis of carbon dots for patterned ﬂuorescent wood ﬁlms rapid fabrication strategy

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Aggregate

Aggregate 2024年第3期5卷 362-373页

作者： Xueqi Chen Jie Zhang Lei Zhang Qiheng Tang Yongping Chen Wenjing guo Liang Chang Wood Composites Laboratory Research Institute of Wood IndustryChinese Academy of ForestryBeijingP.R.China

Fluorescent-patterned materials are widely used in information storage and ***,preparing a patternedﬂuorescent display on a matrix currently requires a time-consuming(hours or even days)and complex multi-step ***,a rapid and mild technique developed for the in-situ controllable synthe-sis ofﬂuorescent nitrogen-doped carbon dots(NCDs)on eco-friendly transparent woodﬁlms(TEMPO-oxidized carboxyl woodﬁlm[TOWF])within a few min-utes was developed.A wood skeleton was employed as the carbon precursor for NCD synthesis as well as the matrix for the uniform and controlled distribution of ***,the in-situ synthesis mechanism for preparing NCDs in TOWF was *** resultingﬂuorescent woodﬁlms have excellent tensile strength(310.0015.57 MPa),high transmittance(76.2%),high haze(95.0%),UV-blocking±properties in the full ultraviolet(UV)range,andﬂuorescent performance that can be modiﬁed by changing the heating *** patterning was sim-ply achieved by regulating the in-situ NCD synthesis regions,and theﬂuorescent patterns were formed within 10 ***ﬂuorescent-patterned woodﬁlms can effec-tively store and encrypt information,and they can interact with external information through a transparent *** work provides a green and efﬁcient strategy for fabricatingﬂuorescent information storage and encryption materials.

关键词： carbon dots ﬂuorescent pattern information encryption in-situ synthesis woodﬁlm

Rapid Access to Chiralα-Alkylated Azacycles via NiH-Catalyzed Asymmetric Migratory Hydroalkylation of N-Heterocyclic Alkenes

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CCS Chemistry 2024年第4期6卷 898-904页

作者： Changpeng Chen Wenqing guo Deyong Qiao Junqian Zhou You Wang Shaolin Zhu State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093 School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007 Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong UniversityShanghai 200240

Asymmetric migratory hydrofunctionalization of isomeric mixtures of alkenes provides a complementary approach for the selective introduction of a functional group into a remote C(sp3)-H ***,the simultaneous control of both regio-and enantioselectivity in this migratory process is a ***α-alkyl-substituted azacycles are key motifs in pharmaceuticals,natural products,and ***,we report a NiH-catalyzed asymmetric migratory hydroalkylation process for their efficient and selective *** this process,easily available isomeric mixtures of N-heterocyclic alkenes can be directly employed as starting materials,convergently delivering a variety of enantioenrichedα-alkylated azacycles with high levels of regio-and *** synthetic utility of this transformation is demonstrated by the facile synthesis of two bioactive alkaloids,(+)-connine and(R)-*** obtained chiralα-alkylated azacycles also readily undergo diverse derivatization,such as deconstructive halogenation and ring contraction.

关键词： alkenes alkylation asymmetric catalysis isomerization nickel

神经网络规则提取及其在转子故障诊断中的应用研究

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振动与冲击 2009年第3期28卷 59-62,72页

作者：陈果南京航空航天大学民航学院南京210016

利用神经网络进行智能诊断所获取的诊断知识难于解释和理解,因此限制了其在智能诊断中的进一步应用,基于此,研究了一种新的基于功能性观点的神经网络规则提取方法,介绍了连续属性离散、训练样本产生、神经网络训练、示例样本产生及规则... 详细信息

利用神经网络进行智能诊断所获取的诊断知识难于解释和理解,因此限制了其在智能诊断中的进一步应用,基于此,研究了一种新的基于功能性观点的神经网络规则提取方法,介绍了连续属性离散、训练样本产生、神经网络训练、示例样本产生及规则提取等关键算法。并与其他方法进行了比较分析。最后,将方法应用于转子故障诊断,通过多功能转子故障模拟实验台获取故障实验样本,利用所提出的神经网络规则提取方法从故障样本中提取了诊断知识规则,并对其进行了解释,结果表明了方法的正确性和有效性。

关键词：神经网络规则提取知识获取转子故障诊断

含不平衡-碰摩-基础松动耦合故障的转子-滚动轴承系统非线性动力响应分析

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振动与冲击 2008年第9期27卷 100-104页

作者：陈果南京航空航天大学民航学院南京210016

建立了滚动轴承支承下的转子系统的不平衡-碰摩-基础松动耦合故障动力学模型。充分考虑了滚动轴承的间隙、非线性赫兹接触力以及由变柔性VC(Varying compliance)振动,综合考虑了转子不平衡、转静碰摩以及基础松动故障的耦合振动。运用... 详细信息

建立了滚动轴承支承下的转子系统的不平衡-碰摩-基础松动耦合故障动力学模型。充分考虑了滚动轴承的间隙、非线性赫兹接触力以及由变柔性VC(Varying compliance)振动,综合考虑了转子不平衡、转静碰摩以及基础松动故障的耦合振动。运用数值积分方法分析了转子旋转速度、滚动轴承间隙、碰摩刚度、转子偏心量及轴承座质量对系统动力响应的影响,并运用分叉图、相平面图、频谱图以及Poincar啨映射研究了系统分叉与混沌特征,发现了含不平衡、碰摩及基础松动耦合故障的转子-滚动轴承系统的非线性动力响应规律。

关键词：转子动力学滚动轴承不平衡碰摩基础松动