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NUMERICAL SOluTION OF 2-D INCOMPRESSIBLE VISCOUS FLOW WITH HIGH ORDER COMPACT SCHEME USING DOMAIN DECOMPOSITION AND MATCHED METHOD

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Journal of Hydrodynamics 2001年第4期13卷 79-82页

作者： Ren, An-lu lu, xiao-dong Zou, Jian-Feng Zhou, Yong-Xia Dept. of Mech. Zhejiang Univ. Hangzhou 310027 China

This paper presents a high-accuracy method for solving 2-D incompressible viscous N-S equations in tensor forms. A domain decomposition method was used to divide the computational domain into several regular blocks with the overlapping grid in order to transfer data between sub-domains and to remove numerical singularity caused by domain decomposition. Using the method and algorithm presented above, the flow passing an ellipse was computed and the formation and evolution of the vortex shedding was successfully simulated.

关键词： Computational fluid dynamics Computational methods Incompressible flow Navier Stokes equations

On Minor Left Prime Factorization Problem for Multivariate Polynomial Matrices

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Journal of Systems Science & Complexity 2024年第3期37卷 1295-1307页

作者： lu dong WANG Dingkang xiao Fanghui School of Mathematics Southwest Jiaotong UniversityChengdu 610031China KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China MOE-LCSM School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China

A new necessary and sufficient condition for the existence of minor left prime factorizations of multivariate polynomial matrices without full row rank is *** key idea is to establish a relationship between a matrix and any of its full row rank *** on the new result,the authors propose an algorithm for factorizing matrices and have implemented it on the computer algebra system *** examples are given to illustrate the effectiveness of the algorithm,and experimental data shows that the algorithm is efficient.

关键词： Free modules Grobner bases minor left prime(MLP) multivariate polynomial matrices polynomial matrix factorizations

可控设计的Co-N/C电催化剂及其氧还原反应活性

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化学试剂 2024年第2期46卷 74-79页

作者：胡鹏张琪婧路肖栋左自豪黄淮学院化学与制药工程学院河南驻马店463000 沈阳化工大学理学院辽宁沈阳110142

能源问题是事关国家发展和安全的重大问题,氧还原反应作为燃料电池阴极半反应近年来成为能源和电催化领域的研究热点之一。通过利用2,9-二甲基-1,10-邻菲啰啉与钴离子的配位形成配合物,将该配合物与炭黑混合均匀,经过中温热解和浓硝酸... 详细信息

能源问题是事关国家发展和安全的重大问题,氧还原反应作为燃料电池阴极半反应近年来成为能源和电催化领域的研究热点之一。通过利用2,9-二甲基-1,10-邻菲啰啉与钴离子的配位形成配合物,将该配合物与炭黑混合均匀,经过中温热解和浓硝酸氧化后得到钴、氮表面修饰的碳负载纳米催化剂Co-N/C。实验首先利用旋转圆盘电极和旋转环盘电极(RRDE)考察了催化剂在不同pH值下的电催化氧还原性能。电化学测试结果表明,在碱性条件下,该催化剂具有与商业Pt/C相近的4电子氧还原催化性能。随后,通过SEM、TEM、XPS、XRD和FT-IR等设备对催化剂进行表征,以揭示Co-N/C催化剂4电子氧还原催化活性增强的来源。运用功能化修饰策略调控碳材料表面的催化活性位点和碳的电子结构,克服了本征碳材料催化活性不高的缺陷,为设计新型非贵金属氧还原反应催化剂提供了一种新的思路。

关键词： Co-N/C 热解表面调控电催化剂氧还原反应

Fully differential optoelectronic integrated receiver implemented by 0.35μm standard CMOS process

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Optoelectronics Letters 2008年第6期4卷 395-398页

作者： YU Chang-liang MAO lu-hong xiao Xin-dong XIE Sheng ZHANG Shi-lin School of Electronic Information Engineering Tianjin University Tianjin 300072 China

A high-bandwidth, high-sensitivity fully differential optoelectronic integrated receiver is implemented in a chartered 3.3 V standard 0.35μm analbg CMOS process. To convert the incident light into a pair of fully differential photo-currents, a novel fully differential photodetector is proposed, which is composed of two completely identical photodiodes. The mea- surement results show that the receiver achieves a 1.11 GHz 3 dB bandwidth and a -13 dBm sensitivity for a 10-12 bit error at 1.5 Gb/s data rate under illumination by 850 nm incident lights.

关键词：光电子联合接收器 CMOS 高灵敏度光电二极管

Microarray-bioinformatics analysis of altered genomic expression profiles between human fetal and infant myocardium

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Chinese Medical Journal 2008年第14期121卷 1257-1264页

作者： KONG Bo LIU Ying-long lu xiao-dong Pediatric Cardiac Center Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background The physiological differences between fetal and postnatal heart have been well characterized at the cellular level. However, the genetic mechanisms governing and regulating these differences have only been partially elucidated. Elucidation of the differentially expressed genes profile before and after birth has never been systematically proposed and analyzed. Methods The human oligonucleotide microarray and bioinformatics analysis approaches were applied to isolate and classify the differentially expressed genes between fetal and infant cardiac tissue samples. Quantitative real-time PCR was used to confirm the results from the microarray. Results Two hundred and forty-two differentially expressed genes were discovered and classified into 13 categories, including genes related to energy metabolism, myocyte hyperplasia, development, muscle contraction, protein synthesis and degradation, extracellular matrix components, transcription factors, apoptosis, signal pathway molecules, organelle organization and several other biological processes. Moreover, 95 genes were identified which had not previously been reported to be expressed in the heart. Conclusions The study systematically analyzed the alteration of the gene expression profile between the human fetal and infant myocardium. A number of genes were discovered which had not been reported to be expressed in the heart. The data provided insight into the physical development mechanisms of the heart before and after birth.

关键词： oligonucleotide microarrays bioinformatics gene ontology heart development

On the Monge–Kantorovich Mass Transfer Problem in Higher Dimensions

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1989-2004页

作者： xiao Jun lu School of Mathematics Southeast UniversityNanjing 210096P.R.China

This paper mainly investigates the approximation of a global maximizer of the Monge–Kantorovich mass transfer problem in higher dimensions through the approach of nonlinear partial differential equations with Dirichlet *** an approximation mechanism,the primal maximization problem can be transformed into a sequence of minimization *** applying the systematic canonical duality theory,one is able to derive a sequence of analytic solutions for the minimization *** the final analysis,the convergence of the sequence to an analytical global maximizer of the primal Monge–Kantorovich problem will be demonstrated.

关键词： Monge-Kantorovich mass transfer singular variational problem canonical duality theory

Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China

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Petroleum Science 2024年第3期21卷 1488-1507页

作者： Gang Li Xian-Ming xiao Bo-Wei Cheng Chen-Gang lu Yue Feng dong-Sheng Li School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing100083 China

The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well *** the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were *** results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM *** pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,*** methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,*** with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption *** GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas *** the geological and geochemical conditions of shale gas formation a

关键词： Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content Controlling factor

Decreased expression of neurotrophic tyrosine receptor kinase 3 is associated with the outflow tract defect of human tetralogy of Fallot

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Chinese Medical Journal 2009年第2期122卷 153-157页

Background The molecular mechanism of human tetralogy of Fallot （TOF） is incompletely defined. Animal models have suggested that neurotrophic tyrosine receptor kinase 3 （NTRK3） might be associated with the outflow tract defect, similar to that seen in human TOF, however, the expression pattern of NTRK3 in human TOF heart tissues has never been investigated. Methods Quantitative real-time PCR （qRT-PCR） and immunohistochemistry were applied to detect NTRK3 mRNA and protein levels in right ventricular outflow tract tissue samples of TOF patients, ventricular septal defect （VSD） patients and normal control infants （n=10 in each group）. Results qRT-PCR analysis indicated that NTRK3 mRNA levels were significantly decreased in the TOF group compared to the VSD group （0.024±0.003 vs 0.085±0.004, P=0.022） and the normal control group （0.024±0.003 vs 0.091±0.002, P=0.006）. Quantitative immunohistochemical analysis showed that NTRK3 protein was mainly localized in the myocardium cytoplasm in all 3 groups. The immunoreactivity of NTRK3 protein was again significantly lower in the TOF group compared to the VSD group （1.42±0.62 vs 14.12±1.83, P=0.023） and the control group （1.42±0.62 vs 16.25±2.31, P=-0.008）. The expression of NTRK3 in the VSD group and in the control group showed no significant differences at both mRNA and protein levels. Conclusions Insufficient expression of NTRK3 is associated with the outflow tract defect of human tetralogy of Fallot and may contribute to the progression of this defect. Chin Med J 2009; 122（2）： 153-157

关键词： tetralogy of Fallot receptor, trkC gene expression

Recent progress of pediatric cardiac surgery in China

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Chinese Medical Journal 2006年第23期119卷 2005-2012页

作者： WU Kai-hong lu xiao-dong LIU Ying-long Pediatric Cardiac Center Department of Surgery CardiovascularInstitute and Fuwai Hospital Chinese Academy of MedicalSciences and Peking Union Medical College Beijing 100037China

Pediatric cardiac surgery in China has madegreat progress since the first successful open heart operation for correction of ventricular septal defect （VSD） with an artificial heart-lung machine in 1958.1 In recent years, the state has paid much attention to both the basic research and the primary, secondary and tertiary prevention of congenital heart disease. The surgical treatment for congenital heart diseases in infancy was listed as one of the Family Planning Technology Specific Projects among the Key Tasks in the Tenth Five-Year Plan. Due to economic and social conditions in China primary or secondary prevention and treatment of congenital heart disease are still in the early phase of development. Therefore, tertiary prevention -- surgical treatment--is still of crucial importance. Here we review the current status of pediatric cardiac surgery in China and highlight the latest advances in this exciting field.

关键词： cardiac surgery cardiopulmonary bypass congenital heart defect pediatrics