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Dependence of tensile properties on microstructural features of bimodal-sized ferrite/cementite steels

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Journal of Iron and Steel Research International 2017年第1期24卷 67-76页

作者： jiang-li ning Yun-li Feng Ming-ming Wang Shen-bai Zheng Jie li College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063009HebeiChina

A medium-carbon steel was processed through different warm rolling techniques,and the microstructural features with bimodal grain size distribution were found to be *** combination of strength and ductility was ameliorated in the steel processed through warm rolling characterized by biaxial *** enhanced strength is attributed to the densely distributed fine intragranular cementite particles and the small grain size in the coarse grain *** enhanced uniform elongation is due to the improved work hardening behavior at the large-strain *** work hardening behavior is predominantly ascribed to the finely dispersed intragranular *** relatively small grain size with nearly equiaxed shape in the coarse grain regions helps stabilize the uniform deformation to a large strain.

关键词： Tensile property Ferrite/cementite steel Bimodal-sized structure Warm rolling Work hardening rate

Tension-Compression Yield Asymmetry Influenced by the Variable Deformation Modes in Gradient Structure Mg Alloys

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 252-266页

作者： jiang-li ning Bo Xu Yun-li Feng Xu-Dong li Xin-Kang li Wei-Ping Tong College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110004China

Surface mechanical attrition treatment(SMAT) was carried out on hot-rolled AZ31 Mg samples along two orthogonal directions;as a result,two types of gradient structures with different grain sizes and texture components in different layers were *** tension-compression yield asymmetry(YA) was studied using samples with different thicknesses,in order to elucidate the effect of combinations of variable deformation modes operating in different layers of the two oriented SMAT *** 0° oriented SMAT sample containing layers with strong basal texture displayed significant YA,because of either dislocation slip or extension twinning domination during tension or *** contrast,the 90° oriented SMAT sample containing layers with coexisting orthogonal texture components had an obviously weakened YA,which was attributed to the multi-deformation modes cooperating during tension or compression,i.e.,extension twinning or detwinning in conjunction with dislocation slips,leading to close yield stresses compared between tension and compression.

关键词： Mg alloy Gradient structure Yield asymmetry Texture Deformation mechanism

Intestinal permeability in patients after surgical trauma and effect of enteral nutrition versus parenteral nutrition

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World Journal of Gastroenterology 2003年第8期9卷 1878-1880页

作者： Xiao-Hua jiang ning li Jie-Shou li, Research Institute of General Surgery, Medical School of Nanjing University, Nanjing 210002, jiangsu Province, China Research Institute of General Surgery Medical School of Nanjing University Nanjing 210002 Jiangsu Province China. dr_jxh@***

AIM: To study the intestinal permeability (IP) following stress of abdominal operation and the different effects on IP of enteral nutrition (EN) and parenteral nutrition (PN).METHODS: Forty patients undergoing abdominal surgery were randomized into EN group and PN group. Each group received nutritional support of the same nitrogen and calorie from postoperative day (POD) 3 to POD 11. On the day before operation (POD-1), POD 7 and POD 12, 10 g of lactulose and 5 g of mannitol were given orally, and urine was collected for 6 hours. Urine excretion ratios of lactulose and mannitol (L/M) were ***: L/M ratios of EN group on POD-1, POD 7 and POD 12 were 0.026±0.017, 0.059±0.026, 0.027±0.017,respectively, and those of PN group were 0.025±0.013,0.080±0.032, 0.047±0.021, respectively. Patients of both groups had elevated L/M ratios on POD 7 vs. POD-1. However the ratio returned toward control level in EN group by POD *** contrast, PN group still had elevated L/M ratios on POD ***: L/M ratio increases for a period of time after surgical trauma and the loss of gut mucosal integrity can be reversed by substitution of enteral nutrition.

关键词：手术后肠内营养肠内营养肠渗透性

Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： Song jiang Congwen Zhu ning jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO

强跟踪CKF及其在惯导系统初始对准中的应用

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中国惯性技术学报 2017年第4期25卷 436-441页

作者：郭士荦许江宁李峰海军工程大学导航工程系武汉430033

容积卡尔曼滤波(CKF)是常用的惯性导航系统(INS)初始对准算法。针对在模型失配和观测噪声干扰情况下常规容积卡尔曼滤波出现精度下降甚至发散的问题,提出了一种自适应渐消滤波算法,引入多重渐消因子对预测误差协方差阵进行调整。设计了... 详细信息

容积卡尔曼滤波(CKF)是常用的惯性导航系统(INS)初始对准算法。针对在模型失配和观测噪声干扰情况下常规容积卡尔曼滤波出现精度下降甚至发散的问题,提出了一种自适应渐消滤波算法,引入多重渐消因子对预测误差协方差阵进行调整。设计了基于滤波残差序列统计特性的滤波状态x^2检验条件,检测滤波器故障并确定是否引入渐消因子,使渐消因子的引入时机更加合理,有效增强了算法的自适应性。仿真试验表明,新算法可以有效提高初始对准精度及鲁棒性。

关键词：容积卡尔曼滤波惯性导航系统初始对准自适应渐消滤波 x^2检验

考虑导热对流和辐射作用的轴对称收扩喷管壁温计算

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航空动力学报 2008年第4期23卷 635-641页

作者：刘友宏李江宁才娟北京航空航天大学能源与动力工程学院北京100083 沈阳发动机设计研究所沈阳110015

基于N-S方程求解了包括引射流、加力燃烧室在内的轴对称收扩喷管内外流一体化的流场,建立了考虑导热、对流换热和辐射换热作用的轴对称收扩喷管各层壁温分布的计算模型,包括隔热屏、喷管筒体、外调节片三层结构.对某航空发动机进行了多... 详细信息

基于N-S方程求解了包括引射流、加力燃烧室在内的轴对称收扩喷管内外流一体化的流场,建立了考虑导热、对流换热和辐射换热作用的轴对称收扩喷管各层壁温分布的计算模型,包括隔热屏、喷管筒体、外调节片三层结构.对某航空发动机进行了多工况计算,燃气的物性随压力、温度和油气比的变化采用了一系列精度较高的计算公式和计算方法.计算结果表明:基于密度求解器求解包含引射流在内的轴对称收扩喷管内外流一体化的跨声速流场是成功的.隔热屏和收扩喷管筒体沿流向温度逐渐升高,喷管筒体壁温在喉部达到最大,在扩张段逐渐降低;收扩喷管外调节片壁温与收扩喷管筒体的壁温变化规律相同,但是壁温最大值则位于喉部前某一位置.计算结果与经过试验验证程序的结果符合良好.

关键词：航空、航天推进系统收扩喷管跨声速流场壁温辐射换热导热对流换热