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Influencing factors on elastic-plastic deformation of multi-layered surfaces under sliding contact

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中国有色金属学会会刊：英文版 2004年第z1期14卷 472-477页

作者： YAN li PAN xin-xiang xu Jiu-jun CHENG Dong Institute of Materials and Technology Dalian Maritime University China Institute of Materials and Technology Dalian Maritime University China Institute of Materials and Technology Dalian Maritime University China Institute of Materials and Technology Dalian Maritime University China

Stress distribution in the gradient multi-layered surface under a sliding contact was investigated using finite element method(FEM). The main structure parameters of layered surface discussed are total layer thickness,layer number and elastic modulus ratio of layer to the substrate. A model of multi-layered surface contact with rough slider was studied. The effect of the surface structure parameters on the elastic-plastic deformation was analyzed.

关键词： gradient multi-layered surface elastic-plastic deformation surface structure parameter FEM

A HIGH-SPEED PHOTOGRAPHIC STUDY OF ULTRASONIC CAVITATION NEAR RIGID BOUNDARY

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Journal of Hydrodynamics 2008年第5期20卷 637-644页

作者： BAI li-xin xu Wei-lin TIAN Zhong li Nai-wen State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China.

This article investigated an existing steady pattern of collapse and rebound （disintegration and aggregation） of cavitation bubbles near rigid boundary in acoustic field. A deformation process of cavitation bubble was accomplished in two acoustic cycles, namely, a spherical bubble collapsed towards the boundary to its minimum volume and then rebounded and grew into a toroidal bubble （or two individual bubbles） in one acoustic cycle, and the toroidal bubble （or two individual bubbles） collapsed towards the center of ring to its minimum volume, and then rebounded into a spherical bubble in the next acoustic cycle. Inertia force plays a key role in the transition between these two states. The microjet produced during the collapse of spherical bubble and the shock wave produced during the collapse of toroidal bubble （or two individual bubbles） impacts the boundary alternately. A cavitation bubble operating in this pattena can thus be an effective corrosion mechanism of rigid boundary.

关键词： cavity ultrasonic cavitation high-speed photography visualization

All-dielectric bowtie waveguide with deep subwavelength mode confinement

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Frontiers of physics 2018年第4期13卷 229-235页

作者： Wen-Cheng Yue Pei-Jun Yao li-xin xu Hai Ming Department of Optics and Optical Engineering University of Science and Technology of China Hefei 230026 China

Plasmonic waveguides and conventional dielectric waveguides have favorable characteristics in photonic integrated circuits. Typically, plasmonic waveguides can provide subwavelength mode confinement, as shown by their small mode area, whereas conventional dielectric waveguides guide light with low loss, as shown by their long propagation length. However, the simultaneous achievement of subwavelength mode confinement and low-loss propagation remains limited. In this paper, we propose a novel design of an all- dielectric bowtie waveguide, which simultaneously exhibits both subwavelength mode confinement and theoretically lossless propagation. Contrary to traditional dielectric waveguides, where the guidance of light is based on total internal reflection, the principle of the all-dielectric bowtie waveguide is based on the combined use of the conservation of the normal component of the electric displacement and the tangential component of the electric field, such that it can achieve a mode area comparable to its plasmonic counterparts. The mode distribution in the all-dielectric bowtie waveguide can be precisely controlled by manipulating the geometric design. Our work shows that it is possible to achieve extreme light confinement by using dielectric instead of lossy metals.

关键词： dielectric waveguide nanophotonics plasmonics photonic integrated circuits silicon

Raman-Assisted Passively Mode-Locked Fiber Laser

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Chinese Physics Letters 2018年第4期35卷 35-37页

作者： Lei Zhao Pei-Jun Yao Chun Gu li-xin xu Department of Optics and Optical Engineering University of Science and Technology of China

We propose and demonstrate a Raman-assisted passively mode-locked Yb-doped fiber laser in a normal dispersion regime. A section of highly nonlinear fiber is adopted to enhance the nonlinearity to extend the bandwidth of the gain spectrum by the stimulated Raman effect. The mode-locked fiber laser emits a broad spectral bandwidth of 64 nm at the-20 dB level and a highly stable pulse operation with a signal-to-noise ratio of 77 dB.

关键词： Raman-Assisted Passively Mode-Locked Fiber Laser SRS

Detection of Toxoplasma gondii in chicken and soil of chicken farms in Nanjing region,China

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Infectious Diseases of Poverty 2017年第1期6卷 532-539页

作者： xin-Chao liu Yu He Deng-Ge Han Zhen-Chao Zhang Ke li Shuai Wang li-xin xu Ruo-Feng Yan Xiang-Rui li College of Veterinary Medicine Nanjing Agricultural UniversityNanjingJiangsu 210095People’s Republic of China

Background:Soil is increasingly recognized as an important source in the transmission of Toxoplasma gondii(***).The aim of this study was to investigate the presence of *** in the soil and to grasp the relationships between the contamination of soil and chicken ***:PCR method based on ***-conserved gene internal transcribed spacer 1(ITS-1)as target gene and EliSA method(sGRA8-EliSA)using the recombinant protein of shortened GRA8 gene of *** as antigen were developed and *** April 2013 to March 2014,a total of 700 soil samples were collected at various sites located in thirty farms categorized as free range farm and scale farm in Nanjing,Jiangsu,China,in different ***,a total of 350 sera of chickens were collected from free range farms to determine the presence of antibodies against *** using ***:The serological results showed that,antibodies were found in 194 of 250(67.14%)samples from farms with *** positive in soil and 41 of 100 samples from farms with *** negative in soil(41.00%)(P<0.01).The PCR detection of soil samples showed that,7(2.0%)of 350 samples collected from feeding zone in free range farms were found positive of ***,whereas no sample was positive in scale *** the seasonal detections,*** was found in 6(3.33%)samples collected in autumn and 1(0.56%)collected in ***:The results indicated that the contamination of *** in soil in the free range farms was higher than that in the scale farms and seroprevalence of *** in chickens in the farm with soil contamination was higher than that with no soil *** soil contamination might be an effective indicator of *** infection in chickens.

关键词： Toxoplasma gondii Chickens farms Soil Chicken

Synchronously Pumped Mode-Locked 1.89 μm Tm-Doped Fiber Laser with High Detuning Toleration

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Chinese Physics Letters 2018年第11期35卷 35-37页

作者： Gen li Yong Zhou Shu-aie li PeiJun Yao Wei-qing Gao Chun Gu li-xin xu Department of Optics and Optical Engineering University of Science and Technology of China

We propose and demonstrate a synchronously pumped mode-locked Tm-doped fiber（TDF） laser without any extra mode-locking elements. Pumped by a 1.56 μm pulse fiber laser, the TDF laser generates 1.17 ps pulses with a spectral width of 9.7 nm and a repetition rate of 9.33 MHz. The emission wavelength is tunable along with the cavity length detuning in a wide range of 3 mm. The high detuning toleration is beneficial to achieve high temperature and vibration stability in all-fiber configuration lasers.

关键词： TDF RBW kHz m Tm-Doped Fiber Laser with High Detuning Toleration Synchronously Pumped Mode-Locked 1.89 Tm

Joint Analysis Method for Major Genes Controlling Multiple Correlated Quantitative Traits

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Agricultural Sciences in China 2006年第3期5卷 179-187页

作者： XIAO Jing WANG xue-feng HU Zhi-qiu TANG Zai-xiang SUI Jiong-ming li xin xu Chen-wu Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology Yangzhou University Yangzhou 225009 P.R.China

Based on the major gene and polygene mixed inheritance model for multiple correlated quantitative traits, the authors proposed a new joint segregation analysis method of major gene controlling multiple correlated quantitative traits, which include major gene detection and its effect and variation estimation. The effect and variation of major gene are estimated by the maximum likelihood method implemented via expectation-maximization （EM） algorithm. Major gene is tested with the likelihood ratio （LR） test statistic. Extensive simulation studies showed that joint analysis not only increases the statistical power of major gene detection but also improves the precision and accuracy of major gene effect estimates. An example of the plant height and the number of tiller of F2 population in rice cross Duonieai x Zhonghua 11 was used in the illustration. The results indicated that the genetic difference of these two traits in this cross refers to only one pleiotropic major gene. The additive effect and dominance effect of the major gene are estimated as -21.3 and 40.6 cm on plant height, and 22.7 and -25.3 on number of tiller, respectively. The major gene shows overdominance for plant height and close to complete dominance for number of tillers.

关键词： multiple correlated quantitative traits major gene joint segregation analysis maximum likelihood estimation,EM algorithm

Microalbuminuria associated with systolic blood pressure and arterial compliance in Chinese metabolic syndrome patients

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Chinese Medical Journal 2007年第16期120卷 1395-1399页

作者： li xin-li xu Qiong LU xin-zheng ZHANG Hai-feng ZHOU Yan-li CAO Ke-jiang HUANG Jun Department of Cardiology First Aftiliated Hospital of Nanjing Medical University Nanjing 210029 China

Background There is significant evidence showing that microalbuminuria and arterial compliance are sensitive markers for early cardiovascular diseases. However, whether microalbuminuria is associated with reduced arterial compliance in Chinese metabolic syndrome （MS） patients remains unknown. Methods According to the definition of MS proposed by ATPⅢ in 2001, USA, subjects （n=362） were divided into three groups according to the number of risk factors： group 1 （control）, group 2 （medium, 〈 3 risk factors） and group 3 （MS, ≥ 3 risk factors）. Both large artery compliance （C1） and small artery compliance （C2） were measured with the CVProfilor DO-2020 Cardiovascular Profiling System, and microalbuminuria was evaluated with the ratio of albumin to urine creatinine. Results （1） As C1 and C2 levels elasticity decreased, albumin creatinine ratio （ACR） and the prevalence of microalbuminuria increased within those groups with MS risk factors. C1 and C2 were negatively correlated with the ranking of MS risk factors, ACR was positively correlated with the ranking of MS risk factors （all P〈0.05）. （2） Subjects were also categorized into a microalbuminuria group and a normal group, C1 and C2 in the microalbuminuria group were lower than in the normal group. （3） Multivariate regression analysis showed that increased systolic blood pressure （SBP） and reduced arterial compliance were the main risk factors for microalbuminuria in the MS group. Conclusions The risk of developing microalbuminuria was higher in the subjects with multiple metabolic abnormalities. Increased systolic blood pressure and reduced arterial compliance may be the main predictors for microalbuminuria in MS.

关键词： metabolic syndrome microalbuminuria arterial elasticity

Higher Education Reform for Computer Major Students in Open and Research Environments

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计算机教育 2012年第10期 57-60页

作者： li xin xu xin-shun JIA Zhi-ping MENG Xiang-xu School of Computer Science and Technology Shandong University Jinan 250101 China

This paper analyzes the requirement of professional computer talents in Chinese universities,and introduces the practice in innovative educational methods taken by Shandong University in an open and research *** order to improve educational quality,we have carried out a serial of reforms,including "Four Experiences" aiming at diversifying study environments and fostering their adaptability and extending their *** are encouraged to join "Research Assistant" program and participate in scientific projects to improve their ability in research and *** also conduct "Engineering Practice" to learn latest modeling and programming *** talents characterized of solid foundation,high quality and strong practical ability are shaped through these initiatives.

关键词： Innovation Education Reform Computer Open Research