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Surface destructive mechanism on high-temperature ablation, supersonic-erosion, dreg-adherence and corrosion

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中国有色金属学会会刊：英文版 2004年第z1期14卷 429-434页

作者： XIAO Jun CHEN Jian-min ZHOU hui-di LI Tie-hu ZHANG qiu-yu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China College of Materials Science and Engineering Northwestern Polytechnic University Xi''an 710072 China State Key Laboratory of Solid LubricationLanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Solid LubricationLanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China College of Materials Science and EngineeringNorthwestern Polytechnic University Xi''an 710072 China College of Materials Science and EngineeringNorthwestern Polytechnic University Xi''an 710072 China

The exhaust and flame from a supersonic airborne missile high-energy smoke-born engine (SAMHSE) may lead to high-temperature ablation, supersonic-erosion, dreg-adherence (HTASED) and corrosion on the launcher slide track, causing serious problems to the operation and decreasing the lifetime of the launcher. Therefore, it is imperative to study the destructive mechanism so as to guarantee the smooth operation and increase the lifetime of military equipments. Accordingly, HTASED and corrosion were systematically observed and analyzed with the emphasis placed on the mechanism investigations making use of a series evaluation tests, typical missile engine simulation tests, national military standard methods, scanning electron microscopy and electrochemical corrosion tests. It is found that the thermal impact of high-temperature flame and supersonic erosion of corrosive melting particle jet of the SAMHSE lead to surface defects of micro-cracks, denudation and corrosive residue. Some defects reach to metal base becoming to "corrosive channels". Repetitive HTASED may cause ablation-adhesion fatigue stress, which enhances the surface corrosion and destruction. HTASED and corrosion are related to the type of a SAMHSE fuel and experience of the launcher. Surface destruction is related to synergistic effects of the HTASED. The ablated and failed Al or steel surface is liable to electrochemical corrosion characterized by pitting in humid and salt-spray environment.

关键词： high-temperature ablation supersonic-erosion dreg-adherence simulating test supersonic airborne missile high-energy smoke-born engine corrosion

Friction of low-dimensional nanomaterial systems

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Friction 2014年第3期2卷 209-225页

作者： Wanlin GUO Jun YIN hu qiu Yufeng GUO Hongrong WU Minmin XUE Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of Education State Key Laboratory of Mechanics and Control of Mechanical Structuresand Institute of NanoscienceNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing 210016China

When material dimensions are reduced to the nanoscale,exceptional physical mechanics properties can be obtained that differ significantly from the corresponding bulk *** we review the physical mechanics of the friction of low‐dimensional nanomaterials,including zero‐dimensional nanoparticles,one‐dimensional multiwalled nanotubes and nanowires,and two‐dimensional nanomaterials-such as graphene,hexagonal boron nitride(h‐BN),and transition‐metal dichalcogenides-as well as topological *** between solid surfaces can serve as rolling and sliding lubrication,while the interlayer friction of multiwalled nanotubes can be ultralow or significantly high and sensitive to interwall spacing and chirality matching,as well as the tube *** interwall friction can be several orders of magnitude higher in binary polarized h‐BN tubes than in carbon nanotubes mainly because of wall ***,current extensive studies on two‐dimensional nanomaterials are comprehensively reviewed *** contrast to their bulk materials that serve as traditional dry lubricants(e.g.,graphite,bulk h‐BN,and MoS_(2)),large‐area high‐quality monolayered two‐dimensional nanomaterials can serve as single‐atom‐thick coatings that minimize friction and *** addition,by appropriately tuning the surface properties,these materials have shown great promise for creating energy‐efficient self‐powered electro‐opto‐magneto‐mechanical ***‐of‐the‐art experimental and theoretical methods to characterize friction in nanomaterials are also introduced.

关键词： friction nanomaterials two‐dimensional materials nanotubes nanoparticles energy dissipation

Nitrogen availability mediates the effects of roots and mycorrhizal fungi on soil organic carbon decomposition:A meta-analysis

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Pedosphere 2024年第2期34卷 289-296页

作者： Tongshuo BAI Yunpeng qiu Shuijin hu Ecosystem Ecology Laboratory College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Department of Entomology&Plant Pathology North Carolina State UniversityRaleigh NC 27695USA

Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain *** on a synthesis of 596 paired observations from both field and greenhouse experiments,we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%,but low soil nitrogen(N)availability(i.e.,high soil C:N ratio)critically mitigated this promotion *** addition,the positive effects of living roots and/or mycorrhizal fungi on organic C decomposition were higher under herbaceous and leguminous plants than under woody and non-leguminous plants,***,there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C ***,roots and/or mycorrhizal fungi significantly enhanced the decomposition of leaf litter but not root *** findings advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.

关键词： arbuscular mycorrhizal fungi ectomycorrhizal fungi leaf litter leguminous plant mycorhizosphere rhizosphere root litter soil C:N ratio

Microstructure and mechanical properties stability of pre-hardening treatment in Al-Cu alloys for pre-hardening forming process

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 539-551页

作者： Liping Tang Pengfei Wei Zhili hu qiu Pang hubei Longzhong laboratory Xiangyang 441000China hubei Key Laboratory of Advanced Technology for Automotive Components School of Automotive EngineeringWuhan University of TechnologyWuhan 430070China hubei Engineering Research Center for Green&Precision Material Forming Wuhan University of TechnologyWuhan 430070China Key Laboratory of Metallurgical Equipment and Control Technology of Ministry of Education School of Machinery and AutomationWuhan University of Science and TechnologyWuhan 430081China

The stability of the microstructure and mechanical properties of the pre-hardened sheets during the pre-hardening forming(PHF)process directly determines the quality of the formed *** microstructure stability of the pre-hardened sheets was in-vestigated by differential scanning calorimetry(DSC),transmission electron microscopy(TEM),and small angle X-ray scattering(SAXS),while the mechanical properties and formability were analyzed through uniaxial tensile tests and formability *** results in-dicate that the mechanical properties of the pre-hardened alloys exhibited negligible changes after experiencing 1-month natural aging(NA).The deviations of ultimate tensile strength(UTS),yield strength(YS),and sheet formability(Erichsen value)are all less than 2%.Also,after different NA time(from 48 h to 1 month)is applied to alloys before pre-hardening treatment,the pre-hardened alloys possess stable microstructure and mechanical properties as ***,with the extension of NA time before pre-hardening treatment from 48 h to 1 month,the contribution of NA to the pre-hardening treatment is *** a yield strength increment of 20 MPa is achieved,with no loss in *** limited enhancement is mainly attributed to the fact that only a limited number of clusters are transformed into Guinier-Preston(GP)zones at the early stage of pre-hardening treatment,and the formation ofθ''phase inhibits the nucleation and growth of GP zones as the precipitated phase evolves.

关键词： Al-Cu alloy pre-hardened alloy natural aging mechanical properties microstructure

Application of Feedforward and Feedback Control Strategy for Wire Rod Hot Rolling Line

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Journal of Iron and Steel Research International 2005年第5期12卷 21-23页

作者： Zhu Hong-xiang HAO Xiao-hong WEN Zhia hu Ze-qiang ZHANG Yao-gen CHEN hu-qiu University of Science and Technology Beijing Beijing 100083 China Baoshan Iron and Steel Co Ltd Shanghai 201900 China

The feedforward and feedback control strategy of water flowrate based on the analysis of thermal process in water cooling box was proposed, and the control strategy was applied to wire rod hot rolling at Baosteel Co. The operation has proved that the strategy can control water flowrate in the cooling water box reasonably to ensure the temperature requirement of the wire discharged from the cooling water box.

关键词： wire feedforward feedback controlled cooling

Clinical operational tolerance in liver transplantation:state-of-the-art perspective and future prospects

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Hepatobiliary & Pancreatic Diseases International 2013年第1期12卷 12-33页

作者： Xi-Qiang Liu Zhi-qiu hu Yao-Fei Pei Ran Tao Center for Organ Transplantation and Department of Surgery Ruijin HospitalShanghai Jiaotong University School of Medicine Department of Surgery Central Hospital of Minghang District

BACKGROUND:Liver transplantation is the definite treatment for end-stage liver diseases with satisfactory ***,untoward effects of life-long immunosuppression prevent the development of alternative strategies to achieve better longterm *** clinical operational tolerance is the ultimate *** SOURCES:A PubMed and Google Scholar search using terms:"immune tolerance","liver transplantation","clinical trial","operational tolerance" and "immunosuppression withdrawal" was performed,and relevant articles published in English in the past decade were ***-text publications relevant to the field were selected and relevant articles from reference lists were also *** was given to those articles which are relevant to the ***:Because of the inherent tolerogenic property,around 20%-30% of liver transplantation recipients develop spontaneous operational tolerance after immunosuppression withdrawal,and the percentage may be even higher in pediatric living donor liver transplantation *** natural killer and γδT cell related markers have been identified to be associated with the tolerant state in liver transplantation *** the progress,clinical operational tolerance is still rare in liver *** the recipient immune system by creating chimerism and regulatory cell therapies is among newer promising means to achieve clinical liver transplantation tolerance in the ***:Although clinical operational tolerance is still rare in liver transplantation recipients,ongoing basic research and collaborative clinical trials may help to decipher the mystery of transplantation tolerance and extend the potential benefits of drug withdrawal to an increasing number of patients in a more predictable fashion.

关键词： immune tolerance liver transplantation clinical trial

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面向时序InSAR的卫星任务规划框架设计

上海航天（中英文） 2024年第2期41卷 137-144页

作者：玉龙飞雪刘国栋邱虎孙静宜张钊屈炜白晨中国四维测绘技术有限公司北京100089 中国资源卫星应用中心北京100094 上海科学技术交流中心上海200235 上海卫星工程研究所上海200240

随着国内自主雷达卫星和差分干涉合成孔径雷达技术(D-InSAR)及衍生的时序InSAR技术的发展,以时间序列上重复观测为主的长周期形变监测的应用与日俱增。对遥感卫星地面任务规划系统来说,规划和管理大量有时序关联的重复任务,从而最大限... 详细信息

随着国内自主雷达卫星和差分干涉合成孔径雷达技术(D-InSAR)及衍生的时序InSAR技术的发展,以时间序列上重复观测为主的长周期形变监测的应用与日俱增。对遥感卫星地面任务规划系统来说,规划和管理大量有时序关联的重复任务,从而最大限度地满足观测要求,是提升以形变监测为使命的雷达卫星运控效率的关键。在综合考虑雷达差分干涉任务序列性、一致性、周期性特征的基础上,设计了一种面向雷达卫星时序InSAR类型任务的规划框架,旨在规划序列任务时,考虑序列整体特性,进行序列任务组间的冲突检测。基于此方法,对现有的地面任务规划系统进行了优化升级,验证了框架的有效性。结果证明:该方法可快速、自动进行序列任务冲突消解,可为长周期序列任务的规划和管理提供设计参考。

关键词：雷达卫星(SAR) 任务规划序列任务差分干涉合成孔径雷达(D-InSAR) 规划框架

A Rank-Sum Testing Method for Multi-Trait Comprehensive Ranking and Its Application

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Agricultural Sciences in China 2010年第8期9卷 1117-1126页

作者： LUO Ru-jiu hu Zhi-qiu KONG Wen-qian SONG Wen XU Chen-wu Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics Ministry of Education/ Yangzhou University Yangzhou 225009 P.R. China Lianyungang Technical College Lianyungang 222006 P.R.China

The rank-sum test is a nonparametric method used in variety evaluation. However, the hypothesis testing of the method hasn＇t been established for multi-trait comprehensive ranking. In this paper, under null hypothesis H0： the variety＇s ranking on each trait is random, the theoretical distribution of sum of ranks （SR） was firstly derived and further used to obtain the critical values for multi-trait comprehensive evaluation in rank-sum testing. A new C＋＋ class and its basic arithmetic were defined to deal with the miscount caused by the precision limitation of built-in data type in common statistical software under large number of varieties and traits. Finally, an application of the theoretical results was demonstrated using five starch viscosity traits of 12 glutinous maize varieties. The proposed method is so simple and convenient that it can be easily used to rank different varieties by multiple traits.

关键词： comprehensive evaluation sum of ranks theoretical distribution critical value

Self-management and self-efficacy status in liver recipients

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Hepatobiliary & Pancreatic Diseases International 2015年第3期14卷 253-262页

作者： Lei Xing Qin-Yun Chen Jia-Ning Li Zhi-qiu hu Ye Zhang Ran Tao Center for Organ Transplantation and Department of Surgery Ruijin Hospital Shanghai Jiaotong University School of Medicine Nursing School Shanghai Jiaotong University School of Medicine Department of General Surgery Central Hospital of Minhang District

BACKGROUND： Liver transplantation （LT） is a viable treatment for patients with end-stage chronic liver diseases. The main aim of LT is to prolong life and improve life quality. However, although survival after LT continues to improve, some aspects of recipient＇s health-related quality of life such as self-man- agement and self-efficacy have been largely ignored.

关键词： liver transplantation self-management self-efficacy quality of life questionnaires