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Dynamical Mechanisms of Effects of Landslides on Long Distance Oil and Gas Pipelines

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 820-824页

作者： ma qingwen WANG Chenghua KONG Jiming Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China Graduate University of Chinese Academy of Sciences Beijing 100049 China

According to the investigations on the oil and gas pipelines such as the Lan-Cheng-Chong pipeline and the Southwest pipeline, there are two ways of laying pipeline： pipelines paralleling （approximately） to the main slide direction and pipelines perpendicular （approximately） to the main slide direction. If earth-retaining walls have been built for pipelines paralleling to the main slide direction, they will prevent the lands from sliding; On the contrary, without earth-retaining walls, the sharp broken rocks in the backfilling soil will scratch the safeguard of the pipeline when the landslides take place. Pipelines perpendicular to the main slide direction can be classified into four types according to the relative positions between pipelines and landslides： Pipelines over the slide planes, pipelines inside the fracture strips of slide planes, pipelines below the slide planes and pipelines behind the backsides of landslides. The different dynamical mechanisms of the process in which landslide acts against pipelines are analyzed based on whether the pipelines are equipped with fixed frusta, because the sliding resistance depends on whether and how many fixed frusta are equipped and the distance between frusta.

关键词： landslide long distance oil and gas pipeline dynamical mechanism

Criterions and Measures of Route Selection of Shallowly Embedded Long-Distance Oil and Gas Pipeline in Mountain Areas

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 787-792页

作者： WANG Chenghua ma qingwen KONG Jiming CHEN Zefu LI Xiuzhen Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China Graduate university of Chinese Academy of Sciences Beijing 100049 China

According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows： the flat landform is the first choice in route alignment. The foot of mountain is the first choice when the route passes by the valley. The route should pass by but the shady and deposited slope and not in sunny and erosive slope as possible as it can. The pipeline should be vertical to contour climbing and descending the mountain except steep slope. Tunnel can be used in crossing foothill. Perpendicularly traversing the river is better than beveling; the worst choice is to put the pipeline along the river. Bypass is the best choice in karsts area. The order of route selection should be pre-choosing, investigation, optimization and adjustment.

关键词： shallowly embedded long-distance oil and gas pipeline criterions and measures of route selection avoiding geological hazards

A Profile of Native Integration Sites Used by φC31 Integrase in the Bovine Genome

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Journal of Genetics and Genomics 2012年第5期39卷 217-224页

作者： Lijuan Qu qingwen ma Zaiwei Zhou Haiyan ma Ying Huang Shuzhen Huang Fanyi Zeng Yitao Zeng Shanghai Institute of Medical Genetics Children＇s Hospital of Shanghai Shanghai Jiao Tong University School of Medicine 24/1400 West Beijing Road Shanghai 200040 China Key Lab of Medical Embryo Molecular Biology Ministry of Health Shanghai 200040 China Shanghai Key Lab of Embryo and Reproduction Engineering Shanghai Municipal Committee of Science and Technology Shanghai 200040 China Institute of Medical Science Shanghai Jiao Tong University School of Medicine 280 South Chongqing Road Shanghai 200025 China

The Streptomyces phage φC31 integrase can efficiently target attB-bearing transgenes to endogenous pseudo attP sites within mammalian genomes. To better understand the activity of φC31 integrase in the bovine genome, DNA sequences of 44 integration events were analyzed, and 32 pseudo attP sites were identified. The majority of these sites share a sequence motif that contains inverted repeats and has similarities to wild-type attP site. Genomic DNA flanking these sites typically contained repetitive sequence elements, such as short and long interspersed repetitive elements. These sequence features indicate that DNA sequence recognition plays an important role in guiding φC31-mediated site-specific integration. In addition, BF27 integration hotspot sites were identified in the bovine genome, which accounted for 13.6% of all isolated integration events and mapped to an intron of the deleted in liver cancer 1 （DLC1） gene. Also we found that the pseudo attP sites in the bovine genome had other features in common with those in the human genome. This study represents the first time that the sequence features of pseudo attP sites specific integrase system has great potential for applied modifications in the bovine genome were analyzed. We conclude that this site- of the bovine genome.

关键词： φC31 integrase Pseudo attP sites Sequence motif Repetitive elements Bovine genome

Association between mitochondrial DNA haplotype compatibility and increased efficiency of bovine intersubspecies cloning

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Journal of Genetics and Genomics 2011年第1期38卷 21-28页

作者： Hao Yan Zhonghai Yan qingwen ma Fei Jiao Shuzhen Huang Fanyi Zeng Yitao Zeng Shanghai Institute of Medical Genetics Shanghai Jiao Tong University 24/1400 West Beijing Road Shanghai 200040 China The Key Lab of Embryo Molecular Biology Ministry of Health China and Shanghai Lab of Embryo and Reproduction Engineering 24/1400 West Beijing Road Shanghai 200040 China Institute of Medical Science Shanghai Jiao Tong University School of Medicine 280 South Chongqing Road Shanghai 200025 China

Reconstructed embryos derived from intersubspecies somatic cell nuclear transfer （SCNT） have poorer developmental potential than those from intrasubspecies SCNT. Based on our previous study that Holstein dairy bovine （HD） mitochondrial DNA （mtDNA） haplotype compatibility between donor karyoplast and recipient cytoplast is crucial for SCNT embryo development, we performed intersubspecies SCNT using HD as donor karyoplast and Luxi yellow heifer （LY） as recipient cytoplast according to mtDNA haplotypes determined by polymerase chain reaction- restriction fragment length polymorphism （PCR-RFLP） analysis. The results demonstrated that intersubspecies mtDNA homotype SCNT embryos had higher pre- and post-implantation developmental competence than intrasubspecies mtDNA heterotype embryos as well as improved blastocyst reprogramming status, including normal H3K9 dimethylation pattern and promoter hypomethylation of pluripotent genes such as Oct4 and Sox2, suggesting that intersubspecies SCNT using LY oocytes maintains HD cloning efficiency and may reprogram HD nuclei to develop into a normal cloned animal ultimately. Our results indicated that karyoplast-cytoplast interactions and mtDNA haplotype compatibility may affect bovine intersubspecies SCNT efficiency. This study on bovine intersubspecies SCNT is valuable for understanding the mechanisms of mtDNA haplotype compatibility between karyoplast and cytoplast impacting the bovine SCNT efficiency, and provides an alternative and economic resource for HD cloning.

关键词： Somatic cell nuclear transfer (SCNT) Mitochondria mtDNA haplotype Epigenetic modification Bovine Intersubspecis Intrasubspecis Developmental competence

Rapid surface texturing to achieve robust superhydrophobicity,controllable droplet impact,and anti-frosting performances

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Friction 2024年第2期12卷 291-304页

作者： qingwen DAI Lei CHEN Jiabao PAN Liping SHI Dameng LIU Wei HUANG Xiaolei WANG College of Mechanical and Electrical Engineering Nanjing University of Aeronautics&AstronauticsNanjing 210016China State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China School of Mechanical Engineering Anhui Polytechnic UniversityWuhu 241000China School of Mechanical Engineering Anhui University of TechnologyMa’anshan 243032China

Robust superhydrophobic surfaces with excellent capacities of repelling water and anti-frosting are of importance for many mechanical *** this work,wear-resistant superhydrophobic surfaces were fabricated by curing a mixture of polyurethane acrylate(PUA)coating and 1H,1H,2H,2H-Perfluorodecyltrichlorosilane(HFTCS)on titanium alloy(TC4)surfaces decorated with micropillars pattern,thus,composite functional surfaces with PUA coating in the valleys around the micropillars pattern of TC4 were *** contact angle on fabricated surfaces could reach 167°.Influences of the geometric parameters of micropillars pattern on the apparent contact angle were investigated,and the corresponding wear-resistant property was *** impact and anti-frosting performances on the prepared surfaces were *** optimized design of surface texture with robust superhydrophobicity,controllable droplet impact,and anti-frosting performances was *** design principle is of promising prospects for fabricating superhydrophobic surfaces in traditional mechanical systems.

关键词： surface texture robust superhydrophobic wear-resistant droplet impact anti-frosting

Activation of proHGF by St14 induces mouse embryonic stem cell differentiation

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Protein & Cell 2016年第8期7卷 601-605页

作者： Yan, Xiaoshuang Xue, Yan Zhou, Yiye Cheng, Yan Yin, Shang ma, qingwen Zeng, Fanyi Shanghai Jiao Tong Univ Sch Med Inst Med Sci Shanghai 200025 Peoples R China Shanghai Jiao Tong Univ Shanghai Childrens Hosp Shanghai Inst Med Genet Shanghai 200040 Peoples R China Minist Hlth Key Lab Med Embryo Mol Biol Shanghai 200040 Peoples R China Shanghai Lab Embryo & Reprod Engn Shanghai 200040 Peoples R China

Embryonic stem cells （ESCs） are capable of unlimited selfrenewal and differentiation, thus generating remarkable interest in their potential therapeutic use in cell-based tissue engineering and regeneration. Stem cell based therapy has been considered as the most promising therapeutic strategy for a range of debilitating diseases （Reynolds and Lamba, 2014）.

关键词： Hepatocyte Growth Factor Pluripotent Gene Protease System Hepatocyte Growth Factor Activator Transmembrane Serine Protease

公路梁桥支座脱空度预测模型及优化算法应用研究

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振动与冲击 2024年第15期43卷 218-227,243页

作者：马世纪乔兰邓乃夫李庆文陈璐北京科技大学城市地下空间工程北京市重点实验室北京100083 北京科技大学土木与资源工程学院北京100083 矿冶科技集团有限公司北京102628

桥梁支座脱空度是桥梁结构的常见病害,对桥梁的安全性和使用寿命产生严重影响。因此,准确获取支座的脱空信息成为一个重要的研究课题。该研究提出了一种两阶段的支座脱空检测方法,第一阶段,基于柔度矩阵对角差值比指标(flexibility diag... 详细信息

桥梁支座脱空度是桥梁结构的常见病害,对桥梁的安全性和使用寿命产生严重影响。因此,准确获取支座的脱空信息成为一个重要的研究课题。该研究提出了一种两阶段的支座脱空检测方法,第一阶段,基于柔度矩阵对角差值比指标(flexibility diagonal matrix change rate,FDMCR)实现脱空支座定位,第二阶段采用BP(back propagation)神经网络进行支座脱空度的预测。研究针对单跨简支梁桥和三跨连续梁桥,通过有限元模拟实现了梁桥理论振型、自振频率的获取,并利用激光多普勒测振系统对室内单跨梁桥开展模态测试,获取实测数据,验证了所提方法的可行性。此外,针对单跨梁桥,分析了单目标粒子群优化算法、混合蛙跳算法、人工蜂群算法(artificial bee colony,ABC)优化算法和多目标非支配排序遗传算法(NSGA-II)优化所构建BP模型的效果。研究结果表明,两阶段的方法可以有效地实现脱空定位和脱空度预测,而优化算法则能够提高预测模型的预测效果,尤其是ABC算法在单跨梁桥脱空度预测模型上表现出更低的预测误差,同时基于支座位置属性构建多目标函数能够缓解单目标中各支座预测效果不均匀的问题。该研究对于预测公路梁桥支座脱空度具有重要的实际意义,并为类似问题的解决提供了新的思路和方法。

关键词：桥梁支座支座脱空度预测柔度矩阵 BP神经网络优化算法

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地面无人平台集群协同控制的研究进展

无人系统技术 2022年第5期5卷 1-11页

作者：马清文徐昕张荣华国防科技大学智能科学学院长沙410073

梳理了近几年来国内外关于地面无人平台集群协同控制几个问题的研究进展。首先,引入典型的地面无人平台模型,并介绍协同控制中处理其非完整约束的几种方法;其次,介绍了地面无人平台集群的协同控制任务;再次,回顾了在建模不确定性、外界... 详细信息

梳理了近几年来国内外关于地面无人平台集群协同控制几个问题的研究进展。首先,引入典型的地面无人平台模型,并介绍协同控制中处理其非完整约束的几种方法;其次,介绍了地面无人平台集群的协同控制任务;再次,回顾了在建模不确定性、外界扰动、地面无人平台发生打滑和侧滑等条件下地面无人平台集群的几种鲁棒协同控制方法。然后,从事件触发控制的角度出发,综述了在通信网络和计算资源受限条件下地面无人平台集群协同控制最新研究成果。最后,给出了地面无人平台集群协同控制中几个值得研究的问题,并对地面无人平台集群协同控制的发展进行展望。

关键词：地面无人平台集群协同控制鲁棒性资源受限事件触发控制

在浸入式冷却中添加新型翅片的混合电池热管理系统

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电气工程学报 2022年第4期17卷 113-121,132页

作者：刘家豪马晴雯上海海事大学海洋科学与工程学院上海201306

为了有效地控制电池的最高温和温差,设计一种冷却系统,采用创新型的螺旋翅片,将其和浸入式冷却系统结合,在该系统下研究了翅片宽度、螺旋圈数、冷却介质流速对电池散热的影响。结果表明增加翅片宽度和螺旋圈数都可以使电池温度得到有效... 详细信息

为了有效地控制电池的最高温和温差,设计一种冷却系统,采用创新型的螺旋翅片,将其和浸入式冷却系统结合,在该系统下研究了翅片宽度、螺旋圈数、冷却介质流速对电池散热的影响。结果表明增加翅片宽度和螺旋圈数都可以使电池温度得到有效降低,翅片宽度从2 mm增加到8 mm时,电池的最高温下降了1.33℃。在此基础上继续讨论螺旋圈数的影响,当圈数从2 Q增加到8 Q时,电池的最高温下降了0.84℃。在翅片宽度为8 mm、螺旋圈数为6 Q时,继续研究冷却介质流速对电池温度的影响,当流速为0.064 m/s时,电池的最高温仅为28.64℃,当流速超过0.024 m/s时,电池的温差呈先上升后下降的趋势,且都小于5℃,压降范围为10.96~93.73 Pa。上述发现为油浸式电池冷却系统提供了更多见解,证明在系统中加入翅片可以有效降低电池的最高温和温差,为强化系统的传热设计提供了参考。

关键词：锂离子电池热管理浸入式系统螺旋翅片

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