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Nanometer lapping technology at high speed

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Science China(Technological Sciences) 2007年第1期50卷 27-38页

作者： yang jiandong TIAN ChunLin WANG ChangXing School of Mechanical and Electrical Engineering Changchun University of Science and TechnologyChangchun 130022China

In floating lapping with solid abrasives, the workpiece is taken as an isolated body. The forces that act on it are analyzed. A differential equation about the forces that act on it is set up, so the forces that act on it and its motion rule are received. Combining it with known lapping tool motion, the relative motion rule between the lapping tool and workpiece is determined too. According to the relative motion, the distribution of abrasives density is designed reasonably, which makes the lapping tool wear uniformly, which, in turn, avoids redressing the lapping tool, saves abra-sives, and increases machining accuracy. Combining it with advantages in high speed lapping with solid abrasives, the low cost, high efficiency nanometer lapping at high speed is realized.

关键词： nanometer machining high speed lapping solid abrasives force analyzing

BASIC EQUATIONS AND WAVE THEORY OF GAS-LIQUID TWO-PHASE TRANSIENT FLOW

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Journal of Hydrodynamics 1992年第1期4卷 83-90页

作者： yang, jiandong Wu, Rongqiao Chen, Jiznzhi Wuhan Univ of Hydraulic and Electric Engineering Wuhan China

This paper systematically discussed the equations for two-phase transient flow and pressure wave and interfacial wave. The behaviour of basic equations was analyzed. The formulas for the wave speed of the pressure wave and the interfacial wave were derived. It was proved that various mathematical models can be uniformed by the integrating model and various wave speed formulas can be uniformed by the universal formula derived. The basic equations for the separated flow model are ill-conditioned because of the unreasonable neglect of the pressure differences between the phases and interfaces. Drift flux model can improve the accuracy if some additional equations are provided. The basic equations for homogeneous flow model are well-conditioned and they can be used in two-phase transient flow, especially in the cases of no velocity slips between various phases fluid.

关键词： wave theory two-phase flow mathematical model

Microsatellite variability reveals high genetic diversity and low genetic differentiation in a critical giant panda population

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Current Zoology 2011年第6期57卷 717-724页

作者： jiandong yang Zhihe ZHANG Fujun SHEN Xuyu yang Liang ZHANG Limin CHEN Wenping ZHANG Qing ZHU Rong HOU College of Animal Science Sichuan Agricultural University Ya＇an 625014 China The Key Laboratory for Conservation Biology of Endangered Wildlife Sichuan Province Chengdu Research Base of Giant Panda Breeding Chengdu 610081 China Wildlife Conservation Division Sichuan Forestry Department Chengdu 610082 China Tangjiahe National Nature Reserve Guangyuan 628109 Sichuan China

Understanding present patterns of genetic diversity is critical in order to design effective conservation and manage- ment strategies for endangered species. Tangjiahe Nature Reserve （NR） is one of the most important national reserves for giant pandas Ailuropoda melanoleuca in China. Previous studies have shown that giant pandas in Tangjiahe NR may be threatened by population decline and fragmentation. Here we used 10 microsatellite DNA markers to assess the genetic variability in the Tang- jiahe population. The results indicate a low level of genetic differentiation between the Hongshihe and Motianling subpopulations in the reserve. Assignment tests using the Bayesian clustering method in STRUCTURE identified one genetic cluster from 42 in- dividuals of the two subpopulations. All individuals from the same subpopulation were assigned to one cluster. This indicates high gene flow between subpopulations. F statistic analyses revealed a low Fzs-value of 0.024 in the total population and implies a randomly mating population in Tangjiahe NR. Additionally, our data show a high level of genetic diversity for the Tangjiahe population. Mean allele number （A）, Allelic richness （AR） and mean expected heterozygosity （HE） for the Tangjiahe population was 5.9, 5.173 and 0.703, respectively. This wild giant panda population can be restored through concerted effort

关键词： Ailuropoda melanoleuca Microsatellite Genetic diversity Genetic differentiation Tangjiahe Nature Reserve

Three New Ranidae Mitogenomes and the Evolution of Mitochondrial Gene Rearrangements among Ranidae Species

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维普期刊数据库

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Asian Herpetological Research 2018年第2期9卷 85-98页

作者： jiandong yang Jiaojiao YU Jiabin LIU Ming ZHOU Biao LI Bo OUyang College of Animal Science and Technology Sichuan Agricultural University Sichuan Key Laboratory of Conservation Biology for Endangered Wildlife Chengdu Research Base of Giant Panda Breeding

Various types of gene rearrangements have been discovered in the mitogenoes of the frog family Ranidae. In this study, we determined the complete mitogenome sequence of three Rana frogs. By combining the available mitogenomic data sets from GenBank, we evaluated the phylogenetic relationships of Ranidae at the mitogenome level and analyzed mitogenome rearrangement cases within Ranidae. The three frogs shared an identical mitogenome organization that was extremely similar to the typical Neobatrachian-type arrangement. Except for the genus Babina, the monophyly of each genus was well supported. The genus Amnirana occupied the most basal position among the Ranidae. The [Lithobates ＋ Rana] was the closest sister group of Odorrana. The diversity of mitochondrial gene arrangements in ranid species was unexpectedly high, with 47 mitogenomes from 40 ranids being classified into 10 different gene rearrangement types. Some taxa owned their unique gene rearrangement characteristics, which had significant implication for their phylogeny analysis. All rearrangement events discovered in the Ranidae mitogenomes can be explained by the duplication and random loss model.

关键词： mitochondrial genomes gene rearrangement molecular phylogeny Ranidae

Protective effects of sodium butyrate on rotavirus inducing endoplasmic reticulum stress-mediated apoptosis via PERK-eIF2αsignaling pathway in IPEC-J2 cells

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Journal of Animal Science and Biotechnology 2021年第4期12卷 1543-1554页

作者： Ye Zhao Ningming Hu Qin Jiang Li Zhu Ming Zhang Jun Jiang Manyi Xiong Mingxian yang jiandong yang Linyuan Shen Shunhua Zhang Lili Niu Lei Chen Daiwen Chen College of Animal Science and Technology Sichuan Agricultural UniversityHuimin Road 211#ChengduSichuan Province 611130P.R.China Institute of Animal Nutrition Sichuan Agricultural UniversityHuimin Road 211#ChengduSichuan Province 611130P.R.China Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education Sichuan Agricultural UniversityChengduSichuan 611130P.R.China

Background:Rotavirus(RV)is a major pathogen that causes severe gastroenteritis in infants and young *** reticulum(ER)stress and subsequent apoptosis play pivotal role in virus ***,the protective mechanisms of intestinal damage caused by RV are poorly defined,especially the molecular pathways related to enterocytes ***,the aim of this study was to investigate the protective effect and mechanism of sodium butyrate(SB)on RV-induced apoptosis of IPEC-J2 ***:The RV infection led to significant cell apoptosis,increased the expression levels of ER stress(ERS)markers,phosphorylated protein kinase-like ER kinase(PERK),eukaryotic initiation factor 2 alpha(eIF2α),caspase9,and *** PERK pathway using specific inhibitor GSK subsequently reversed RV-induced cell *** SB treatment significantly inhibited RV-induced ERS by decreasing the expression of glucose regulated protein 78(GRP78),PERK,and eIF2α.In addition,SB treatment restrained the ERS-mediated apoptotic pathway,as indicated by downregulation of C/EBP homologous protein(CHOP)mRNA level,as well as decreased cleaved caspase9 and caspase3 protein ***,siRNA-induced GPR109a knockdown significantly suppressed the protective effect of SB on RV-induced cell ***:These results indicate that SB exerts protective effects against RV-induced cell apoptosis through inhibiting ERS mediated apoptosis by regulating PERK-eIF2αsignaling pathway via GPR109a,which provide new ideas for the prevention and control of RV.

关键词： Apoptosis IPEC-J2 PERK-eIF2α Rotavirus Sodium butyrate

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核燃料厂房通风机振动故障诊断分析

核动力工程 2018年第6期39卷 178-181页

作者：杨建东广西防城港核电有限公司

对防城港核电厂1号机组核燃料厂房2#通风机组实施状态监测,发现异常振动现象,结合通风机结构形式,通过优化振动数据采集参数设置,捕捉特定的故障频率信号,进行频谱分析和故障诊断,发现电机振动超标的直接原因是拍频共振,并成功识别潜在... 详细信息

对防城港核电厂1号机组核燃料厂房2#通风机组实施状态监测,发现异常振动现象,结合通风机结构形式,通过优化振动数据采集参数设置,捕捉特定的故障频率信号,进行频谱分析和故障诊断,发现电机振动超标的直接原因是拍频共振,并成功识别潜在的皮带传动缺陷。根据诊断结果可为预防性维修提供精确的处理方案,有效降低振动水平,保障设备健康稳定运行。

关键词：通风机皮带传动频谱分析拍频共振故障诊断

DISCUSSING　ON　SOLID　ABRASIVE　LAPPING　PATH

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Chinese Journal of Mechanical Engineering 1997年第2期10卷 101-105,140页

作者： yang jiandong ,Wen XuehengChangchun Institute of Optics and Fine MechanicsZhu Yanqiu, Wang Lijiang Jilin University of Technology

Relative motion path between lapping tool and workpiece in plane solid abrasive lapping is dis- cussed and its path model is set up. The paths simulate. by this model are compared with the one got in experiments. The changing relationship of workpiece rotating speed with the main spindle rotating speed and eccentricity is also discussed.

关键词： Lapping ,Path Solid abrasive

基于1D-3D耦合方法的变顶高尾水洞明满混合流的研究

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水力发电学报 2015年第5期34卷 108-113页

作者：安华杨建东武汉大学水资源与水电工程科学国家重点实验室武汉430072

水电站过渡过程中变顶高尾水洞的非恒定流通常为明满混合流,其流态较为复杂,三维流动现象较为明显。对明满混合流能否准确地模拟直接关系到机组的调节保证参数。为此本文采用1D-3D耦合方法对其进行数值模拟,并与传统的虚拟狭缝法模拟结... 详细信息

水电站过渡过程中变顶高尾水洞的非恒定流通常为明满混合流,其流态较为复杂,三维流动现象较为明显。对明满混合流能否准确地模拟直接关系到机组的调节保证参数。为此本文采用1D-3D耦合方法对其进行数值模拟,并与传统的虚拟狭缝法模拟结果进行对比。由此,探讨两种方法在模拟明满混合流分界面波动过程的差异以及对尾水管最小动水压力的影响。结果表明:虚拟狭缝法存在较明显的缺陷,需要做出相应的改进。

关键词：计算水力学变顶高尾水洞明满混合流 1D-3D耦合方法虚拟狭缝法尾水管最小动水压力

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导叶关闭规律的优化及对水力过渡过程的影响

水力发电学报 1999年第2期18卷 75-83页

作者：杨建东武汉水利电力大学

优化导叶关闭规律是解决水电站机组调节保证计算的一个重要的手段。然而面对实际工程问题时如何优化导叶关闭规律、不同的导叶关闭规律对水力过渡过程有何不同的影响、选取的导叶关闭规律能否安全有效地实现等，至今缺少明确的答案和恰... 详细信息

优化导叶关闭规律是解决水电站机组调节保证计算的一个重要的手段。然而面对实际工程问题时如何优化导叶关闭规律、不同的导叶关闭规律对水力过渡过程有何不同的影响、选取的导叶关闭规律能否安全有效地实现等，至今缺少明确的答案和恰如其分的评价，以致难以发挥导叶关闭规律应起的作用。本文从结合国内某些大型水电工程。

关键词：导叶关闭规律水力过渡过程水电站机组调节