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Thermo-mechanical properties of RTM-made carbon fibre/polyimide composite attaching collar under transient heating

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Chinese Journal of Aeronautics 2023年第3期36卷 393-405页

作者： Shengda jiang Chuyang LUO Peng ZHANG jianwen BAO Peipei CAI Xufeng XIA Shanghai High Performance Fibers and Composites Center(Province-Ministry Joint) Center for Civil Aviation CompositesDonghua UniversityShanghai 201620China AVIC Composite Technology Center Science and Technology on Advanced Composites LaboratoryBeijing 101300China Luoyang Optoelectro Technology Development Center Luoyang 471009China

This study focuses on the thermo-mechanical properties of Carbon Fibre/Polyimide Composite(CFPC)attaching collars under transient heating.The CFPC attaching collars were fabricated by a high-temperature resin transfer moulding process,and their thermo-mechanical properties under the conditions of simultaneous transient heating and bending load were investigated.The results show that the attaching collar tends to fail at 118% of the limit load.The failure mode includes the fracture of the connecting screws,local extrusion damage of the hole edges,and slight ablation damage at the outer plies.And there is no observable residual deformation in the composite attaching collar.Furthermore,considering that the material properties vary with temperature,a progressive damage model based on the sequential thermo-mechanical coupling method was established to study the failure mechanism of the attaching collar.Finally,the damage factor of the CFPC was calculated to assess the safety status of the attaching collar.The results show that the primary damage modes of the composite attaching collar are intralaminar failure,which mainly occurs at the heat insulation layer and the hole edges,and these slightly affect the structural bearing capacity.A good correlation between the experiment and FEA is obtained.The test methods and analysis models proposed contribute to the safety assessment of composite structures under transient heating.

关键词： Polyimide composites Progressive damage model Resin transfer moulding Thermo-mechanical properties Transient heating

Structural shifts in the intestinal microbiota of rats treated with cyclosporine A after orthotropic liver transplantation

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Frontiers of Medicine 2019年第4期13卷 451-460页

作者： Junjun Jia Xinyao Tian Jianwen Jiang Zhigang Ren Haifeng Lu Ning He Haiyang Xie Lin Zhou Shusen Zheng Department of Hepatobiliary and Pancreatic Surgery the First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China Key Laboratory of Combined Multi-Organ Transplantation Ministry of Public Health Collaborative Innovation Center for Diagnosis and Treatment ofInfectious Diseases the First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases the First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China

Understanding the effect of immunosuppressive agents on intestinal microbiota is important to reduce the mortality and morbidity from orthotopic liver transplantation (OLT). We investigated the relationship between the commonly used immunosuppressive agent cyclosporine A (CSA) and the intestinal microbial variation in an OLT model. The rat samples were divided as follows:(1) N group (normal control);(2) I group (isograft LT, Brown Norway [BN] rat to BN);(3) R group (allograft LT, Lewis to BN rat);and (4) CSA group (R group treated with CSA). The intestinal microbiota was assayed by denaturing gradient gel electrophoresis profiles and by using real-time polymerase chain reaction. The liver histopathology and the alanine/aspartate aminotransferase ratio after LT were both ameliorated by CSA. In the CSA group, the numbers of rDNA gene copies of Clostridium cluster I, Clostridium cluster XIV, and Enterobacteriaceae decreased, whereas those of Faecalibacterium prausnitzii increased compared with the R group. Cluster analysis indicated that the samples from the N, I, and CSA groups were clustered, whereas the other clusters contained the samples from the R group. Hence, CSA ameliorates hepatic graft injury and partially restores gut microbiota following LT, and these may benefit hepatic graft rejection.

关键词： microbial community liver transplantation immunosuppressive agents cyclosporine A

Metal-Organic Frameworks for Energy, Environmental and Pharmaceutical Applications: A Computational Perspective

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Metal-Organic Frameworks for Energy, Environmental and Pharm...

Research on monitoring strategy of loess landslide with GNSS meteorology

The 1st International Congress on Advanced Materials 2011

作者： Jianwen Jiang Department of Chemical and Biomolecular Engineering National University of Singapore

Metal-organic frameworks (MOFs) have emerged as a new class of hybrid nanoporous materials. Composed of metal-oxide clusters and organic linkers, MOFs possess extremely large surface area (up to 6000 m 2 /g) and high porosity (up to 90%) ever recorded for crystalline materials. The judicious choice of controllable organic linkers and the variation of metal oxides allow the pore sizes, volumes and functionalities of MOFs to be tailed in a rational way for designable architectures. MOFs provide a wealth of opportunities for engineering new functional materials and are considered as versatile candidates for storage, separation, sensing, catalysis, and other important applications. An overview will be presented for the recent state-of-the-art computational studies on energy, environmental and pharmaceutical applications of MOFs. A few typical examples will be given: (1) CO 2 storage is examined in a series of MOFs by varying metal center, organic linker, functional group and framework topology. The affinity with CO 2 is enhanced by the addition of functional groups and the formation of constricted pores;both lead to a stronger adsorption at low pressures. The organic linker plays a critical role in tuning the free volume and accessible surface area, and thus largely determines CO 2 adsorption at high pressures. The capacities at high pressures correlate well with framework density, free volume, porosity and accessible surface area of MOFs. These molecular-based structure-function correlations are useful for a priori prediction of CO 2 capacity and for rational screening of MOFs toward the high-efficacy CO 2 storage. (2) The separation of CO 2 /CH 4 mixture is studied in MOFs with unique characteristics such as exposed metals, catenation and extra-framework ions. The catenated MOFs have a higher selectivity than their non-catenated counterparts. CO 2 /CH 4 selectivity in charged MOF is substantially higher than in neutral MOFs, and the highest among various MOFs reported to date. The study reveals that the selectivity

关键词： Metal-Organic Frameworks CO2 Storage and Capture Drug Delivery.

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Research on monitoring strategy of loess landslide with GNSS...

Effect of substrate cooling on the epitaxial growth of Ni-based single-crystal superalloy fabricated by direct energy deposition

第十三届中国卫星导航年会

作者： Jianwen Jiang Shuangcheng Zhang Cunpeng Jia Xuqiao Wang Xinrui Li College of Geology Engineering Chang'an University State Key Laboratory of Geo-Information Engineering Lanzhou Petrochemical University of Vocational Technology

Landslide is a common geological disaster with wide distribution and great harmfulness, which poses a serious threat to the safety of human life and property. Rainfall is the biggest influencing factor of loess landslide. Since rainfall is closely related to the PWV content, the Global Navigation Satellite System（GNSS） can not only obtain the three-dimensional deformation information of the location of the observation station, It can also be used to invert the moisture content. In order to make GNSS play a better role in landslide monitoring, based on the landslide event in Linxia city, In this paper, GAMIT software is used to calculate the data of three IGS stations combined with the monitoring station in Linxia city, and the PWV is inverted and compared with the rainfall, The PWV value accumulates continuously from low to high, and when it reaches a certain peak value and lasts for a period of time, rainfall events will occur. The results show that PWV has an obvious correspondence with actual rainfall, which proves the feasibility of ground-based GNSS inversion of moisture content. The three-dimensional surface deformation information obtained by the universal receiver is analyzed synthetically. The experimental results show that there is a correlation between the shape variables, PWV and rainfall, which proves the feasibility of GNSS meteorology for loess landslide monitoring. By analyzing the historical meteorological data of Linxia city, the rainy season is concentrated in May to September, during which the real-time calculation scheme can be adopted. When there is less rainfall from October to April of the next year, sky solution or weekly solution can be adopted. In addition, when the PWV is greater than 20 mm, real-time calculation can be performed to monitor landslide conditions. The cumulative PROCESS of PWV before rainfall is of great significance for monitoring loess landslide. Therefore, GNSS inversion of PWV provides a new monitoring strategy for loess landslide.

关键词： Loess Landslide Global Navigation Satellite System Precipitable Water Vapor Universal receiver

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Journal of Materials Science & Technology 2021年第3期62卷 148-161页

作者： jianwen Nie Chaoyue Chen Longtao Liu Xiaodong Wang Ruixin Zhao Sansan Shuai jiang Wang Zhongming Ren State Key Laboratory of Advanced Special Steels School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The columnar-to-equiaxed transition(CET)or the formation of stray grains in the laser melting deposition is the least desirable for the repair of single-crystal blades.In this work,the forced water-cooling was conducted on a single-crystal Rene N5 substrate during the direct energy deposition(DED).The single track remelting,one-layer,two-layer,and eight-layer depositions were investigated to explore the grain growth mechanism.The solidification conditions of the DED process,including temperature field,temperature gradient,and solidification speed,were numerically analyzed by a finite element model.The single-track remelting results showed that the fraction of columnar crystal regions increases from55.81%in the air-cooled sample to 77.14%in the water-cooled one.The single-track deposits of one-and two-layer have the same trend,where the proportion of columnar crystal height was higher under the forced water-cooled condition.The electron backscattered diffraction(EBSD)grain-structure maps of an eight-layer deposit show that the epitaxial growth height increases from 1 mm in the air-cooling sample to 1.5 mm in the water-cooling one.The numerical results showed that the tempe rature gradient in[0011 direction was significantly increased by using forced water-cooling.In conclusion,the in-situ substrate cooling can become a potential method to promote epitaxial growth during DED via the influence on CET occurrence.

关键词： Direct energy deposition Epitaxial growth Columnar-to-equiaxed transition(CET) Temperature gradient

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文登圣经山《太上老子道德经》摩崖年代考

中国道教 2022年第3期 45-49页

作者：费建文姜生威海市文登区博物馆四川大学文化科技中心

山东省威海市文登区圣经山上著名的早期全真道文物《太上老子道德经》摩崖刻石,位于文登区西北20公里的葛家镇,2006年6月公布为第六批全国重点文物保护单位。区域内主要有分布于山巅的《太上老子道德经》摩.崖石刻、圣经山记事石刻、岩... 详细信息

山东省威海市文登区圣经山上著名的早期全真道文物《太上老子道德经》摩崖刻石,位于文登区西北20公里的葛家镇,2006年6月公布为第六批全国重点文物保护单位。区域内主要有分布于山巅的《太上老子道德经》摩.崖石刻、圣经山记事石刻、岩顶桃形水池和分布于半山的龙王庙、洞天刻石、福地刻石、混元殿、众仙坟、朝阳洞等多处早期全真道遗存。

关键词：老子道德经早期全真道全国重点文物保护单位朝阳洞山东省威海市圣经龙王庙洞天

Managing chronic wounds during novel coronavirus pneumonia outbreak

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Burns & Trauma 2020年第1期8卷 347-350页

作者： Rui Wang Yanzhen Peng Yufeng jiang jianwen Gu Wound Healing Department PLA Strategic Support Force Characteristic Medical CenterBeijing 100101China Center of Minimally Invasive Gynecological Surgery of Beijing Obstetrics and Gynecology Hospital Affiliated to Capital Medical University Beijing 10006China Prevention and Control Group of COVID-19 PLA Strategic Support Force Characteristic Medical CenterBeijing 100101China

To the Editor In December of 2019,a widespread outbreak of novel coro-navirus pneumonia(NCP)occurred in Wuhan,China.On January 12,2020,the virus causing NCP was named as“2019-nCoV”by the World Health Organization[1,2].The World Health Organization renamed NCP as“COVID-19”.COVID-19 is a highly contagious respiratory virus that poses a serious threat to human health worldwide.At present,COVID-19 has been classified as a Class B infectious disease in China,and management of Class A infectious diseases has been adopted.As of March 10,2020,80932 cases were diagnosed and confirmed as COVID-19 in China,with 60002 cured cases and 3140 death.Meanwhile,34656 cases were diagnosed and confirmed as COVID-19 abroad.

关键词： China. fir aging

税法总则目标下税收效率原则的功能定位与制度保障

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税务研究 2023年第8期 67-75页

作者：刘剑文江利杰辽宁大学法学院

凝聚改革共识、实现税法体系融贯、指引税法规则完善,是税法总则制定的基础。既往学术界对税收效率原则疏于关照,相关论述多借鉴自税收学成果,未在税法领域进行充分的体系构建,难以权衡实践中税收效率原则与税收法定原则、税收公平原则... 详细信息

凝聚改革共识、实现税法体系融贯、指引税法规则完善,是税法总则制定的基础。既往学术界对税收效率原则疏于关照,相关论述多借鉴自税收学成果,未在税法领域进行充分的体系构建,难以权衡实践中税收效率原则与税收法定原则、税收公平原则间的冲突。税收效率原则以“弃实就虚”为特征,是资源有限背景下实现民主目标的漏洞填补方式,即:对税收法定进行“目的性扩张”,导向一种相对法定主义;对税收公平进行“目的性限缩”,体现为相对公平的要求。在建制逻辑上,既要遵循比例原则的理论检验,也要经由立法程序的共识凝聚与个案平衡的制度保障,实现税收效率原则与税收法定原则、税收公平原则的统一。

关键词：税法总则税收效率原则技术正义比例原则税收法定原则

纵向磁场中触头材料和直径对中频真空电弧特性的影响

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中国电机工程学报 2015年第20期35卷 5367-5374页

作者：蒋原武建文北京航空航天大学自动化科学与电气工程学院北京市海淀区100191

利用振荡回路在杯状纵磁灭弧室中产生频率400 Hz的中频真空电弧,在开距为3mm的条件下,选取触头材料为纯Cu、Cu-W-WC合金和Cu Cr50合金,直径为41 mm和58 mm的灭弧室进行不同电流等级的实验,对比分析电弧电压和电弧形态的变化。实验结果表... 详细信息

利用振荡回路在杯状纵磁灭弧室中产生频率400 Hz的中频真空电弧,在开距为3mm的条件下,选取触头材料为纯Cu、Cu-W-WC合金和Cu Cr50合金,直径为41 mm和58 mm的灭弧室进行不同电流等级的实验,对比分析电弧电压和电弧形态的变化。实验结果表明:中频真空电弧的特性和真空灭弧室的开断性能,与触头材料和直径有密切的关系;对直径相同的触头,Cu Cr50合金触头的开断能力强于纯Cu和Cu-W-WC合金;随着触头直径的增大,电弧电压减小,电弧扩散均匀且更稳定,灭弧室的开断能力更强。

关键词：纵向磁场触头材料触头直径中频真空电弧