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基于耕地质量评价的鄱阳湖区耕地整理规划

农业工程学报 2007年第5期23卷 75-80页

作者：蔡海生林建平朱德海中国农业大学信息与电气工程学院北京100083 江西农业大学国土资源与环境学院南昌330045

区域耕地质量评价是耕地整理的基础工作,为耕地整理专项规划、耕地整理项目设计提供了科学依据。从耕地整理的基本要求出发,选取耕地自然条件和耕地利用条件2个基本因素,土层厚度、土壤质地、土壤有机质、土壤侵蚀、地形坡度、排灌状况... 详细信息

区域耕地质量评价是耕地整理的基础工作,为耕地整理专项规划、耕地整理项目设计提供了科学依据。从耕地整理的基本要求出发,选取耕地自然条件和耕地利用条件2个基本因素,土层厚度、土壤质地、土壤有机质、土壤侵蚀、地形坡度、排灌状况、田间道路状况、田块规整度等8个影响因子,建立耕地质量评价指标体系。采用多因素综合评判法将环鄱阳湖区12县(市)的耕地分成4个等级,分析其空间分异特征,并结合各区域耕地质量主要限制因子,提出可行性耕地整理措施,为区域耕地整理宏观控制提供了一种新思路。

关键词：耕地质量评价空间分异耕地整理鄱阳湖区

列车车轮踏面制动温度循环试验与温度场仿真分析

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中国铁道科学 2010年第3期31卷 70-75页

作者：应之丁李小宁林建平朱建安同济大学铁道与城市轨道交通研究院上海200092 同济大学机械工程学院上海200092

在分析货物列车踏面制动方式下车轮踏面热振裂纹和车轮热疲劳裂纹产生机理的基础上,以国内碾钢车轮材料为对象进行踏面制动温度场试验,重点研究制动过程中摩擦热源向转动车轮踏面表面传热的关系,模拟车轮旋转周期内闸瓦摩擦生热和对流... 详细信息

在分析货物列车踏面制动方式下车轮踏面热振裂纹和车轮热疲劳裂纹产生机理的基础上,以国内碾钢车轮材料为对象进行踏面制动温度场试验,重点研究制动过程中摩擦热源向转动车轮踏面表面传热的关系,模拟车轮旋转周期内闸瓦摩擦生热和对流换热交替变化的规律,建立车轮制动过程瞬态温度场三维有限元模型,改进以整体输入热流和对流换热的简化模式为基础的传统理论的热应力计算方法。通过在摩擦制动动力试验台进行的制动试验,证明计算模型从宏观和细节方面比较完整地反映了车轮踏面制动热温度场的实际工况。为确定车轮踏面制动极限和作用方式、列车制动距离等技术规范提供计算依据。

关键词：踏面制动热疲劳温度场有限元模型试验研究

基于改进全卷积神经网络的图像单像素边缘提取

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计算机工程 2020年第1期46卷 262-270页

作者：刘畅张剑林建平同济大学机械与能源工程学院

为实现复杂背景图像中高精度边缘的准确提取,提出一种改进的单像素边缘提取算法。在改进的全卷积神经网络中,通过添加辅助输出层与采取多尺度输入的方式初步提取图像多像素边缘,并利用分水岭算法对多像素边缘进行细化重定位,从而获取图... 详细信息

为实现复杂背景图像中高精度边缘的准确提取,提出一种改进的单像素边缘提取算法。在改进的全卷积神经网络中,通过添加辅助输出层与采取多尺度输入的方式初步提取图像多像素边缘,并利用分水岭算法对多像素边缘进行细化重定位,从而获取图像单像素边缘。磁瓦图像上的应用结果表明,该算法具有较强的鲁棒性,能提取高精度且完整连续的单像素边缘。

关键词：单像素边缘检测全卷积神经网络分水岭算法距离误差磁瓦图像

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钢/FRP复合板的力学性能

同济大学学报（自然科学版） 2019年第S1期47卷 43-48页

作者：林野闵峻英林建平李永记徐南婕滕昊同济大学机械与能源工程学院上海201804 同济大学上海市地面交通工具空气动力与热环境模拟重点试验室上海201804

对由高强钢DP980和碳纤维(CF)或芳纶纤维(AF)单向布通过环氧树脂粘贴制成钢/纤维增强复合材料(FRP)复合板,在拉伸、弯曲和压缩条件下进行了力学性能试验研究.通过单向拉伸、单向压缩和三点弯曲试验,获得了包含不同FRP种类、纤维方向的钢... 详细信息

对由高强钢DP980和碳纤维(CF)或芳纶纤维(AF)单向布通过环氧树脂粘贴制成钢/纤维增强复合材料(FRP)复合板,在拉伸、弯曲和压缩条件下进行了力学性能试验研究.通过单向拉伸、单向压缩和三点弯曲试验,获得了包含不同FRP种类、纤维方向的钢/FRP复合板的承载-位移关系.与单一高强钢板DP980比较,钢/FRP复合板具有更高的刚度、承载能力以及抗屈曲失稳能力.粘贴300 g碳纤维单向布的钢/FRP复合板在拉伸、压缩及弯曲条件下最大载荷较单一高强钢板DP980分别提升了44.0%、104.9%和170.1%,初始刚度分别提升了20.5%、28.7%和126.8%.

关键词：纤维增强复合材料(FRP) 复合板力学性能轻量化

Improved 5-Aminolevulinic Acid Production with Recombinant Escherichia coli by a Short-term Dissolved Oxygen Shock in Fed-batch Fermentation

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Chinese Journal of Chemical Engineering 2013年第11期21卷 1291-1295页

作者：杨俊朱力傅维琦林逸君林建平岑沛霖 Key Laboratory of Biomass Chemical Engineering of Ministry of Education Departnaent of Chemical and BiologicalEngineering Zhejiang University Hangzhou 310027 China Center for Systems Biology University of Iceland Reykjavik Iceland

5-Aminolevulinic acid （ALA） is a common precursor for tetrapyrrole compounds in all kinds of organ isms and has wide applications in agriculture and medicines. In this study, a new strategy, i.e. short-term dissolved oxygen （DO） shock during aerobic fermentation, was introduced to produce 5-aminolevulinic acid with a recombi-nant E. coli. Effects of duration time of DO shock operation on plasmid concentration, intracellular ALA synthase （ALAS） activity and ALA production were investigated in Erlenmeyer shake flasks. The results indicated that both ALAS activity and ALA yield were enhanced in an anaerobic operation of 45 rain in the early exponential phase during fermentation, while they decreased when the anaerobic operation time was further increased to 60 rain. The DO shock protocol was confirmed with the fed-batch fermentation in a 15 L fermenter and the ALA production achieved 9.4 g.L-1 （72 mmol.L-1）, which is the highest yield in the fermentation broth reported up to now.

关键词： 5-aminolevulinic acid synthase activity dissolved oxygen shock fed-batch fermentation recombinantE. coli

Composition,function,and timing:exploring the early‑life gut microbiota in piglets for probiotic interventions

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Journal of Animal Science and Biotechnology 2024年第2期15卷 659-678页

作者： jianping Quan Cineng Xu Donglin Ruan Yong Ye Yibin Qiu Jie Wu Shenping Zhou Menghao Luan Xiang Zhao Yue Chen Danyang lin Ying Sun Jifei Yang Enqin Zheng Gengyuan Cai Zhenfang Wu Jie Yang College of Animal Science and National Engineering Research Center for Breeding Swine Industry South China Agricultural UniversityGuangzhouGuangdongPeople’s Republic of China Guangdong Provincial Key Laboratory of Agro‑Animal Genomics and Molecular Breeding South China Agricultural UniversityGuangzhouGuangdongChina Yunfu Subcenter of Guangdong Laboratory for lingnan Modern Agriculture YunfuGuangdongChina National Engineering Research Center for Breeding Swine Industry Wens Foodstuff Group Co.Ltd.YunfuGuangdongPeople’s Republic of China

Background The establishment of a robust gut microbiota in piglets during their early developmental stage holds the potential for long-term advantageous ***,the optimal timeframe for introducing probiotics to achieve this outcome remains *** In the context of this investigation,we conducted a longitudinal assessment of the fecal microbiota of 63 piglets at three distinct pre-weaning time ***,we gathered vaginal and fecal samples from 23 *** 16S rRNA gene and metagenomic sequencing methodologies,we conducted a comprehensive analysis of the fluctuation patterns in microbial composition,functional capacity,interaction networks,and colonization resistance within the gut microbiota of *** the piglets progressed in age,discernible modifications in intestinal microbial diversity,composition,and function were observed.A source-tracking analysis unveiled the pivotal role of fecal and vaginal microbiota derived from sows in populating the gut microbiota of neonatal *** D21,the microbial interaction network displayed a more concise and efficient configuration,accompanied by enhanced colonization resistance relative to the other two time ***,we identified three strains of Ruminococcus *** D10 as potential candidates for improving piglets’weight gain during the weaning *** The findings of this study propose that D10 represents the most opportune juncture for the introduction of external probiotic interventions during the early stages of piglet *** investigation augments our comprehension of the microbiota dynamics in early-life of piglets and offers valuable insights for guiding forthcoming probiotic interventions.

关键词： Colonization resistance Intestinal microbiota Piglet Weaning Weight gain

Ordered mesoporous nanofibers mimicking vascular bundles for lithium metal batteries

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National Science Review 2024年第5期11卷 291-302页

作者： Xiaohang Zhu Mengmeng Liu Fanxing Bu Xin-Yang Yue Xiang Fei Yong-Ning Zhou Anqi Ju jianping Yang Pengpeng Qiu Qi Xiao Chao lin Wan Jiang Lianjun Wang Xiaopeng Li Wei Luo State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Institute of Functional Materials College of Materials Science and Engineering Donghua University Institute for Conservation of Cultural Heritage Shanghai University Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong University Department of Materials Science Fudan University

Hierarchical self-assembly with long-range order above centimeters widely exists in nature. Mimicking similar structures to promote reaction kinetics of electrochemical energy devices is of immense interest, yet remains challenging. Here, we report a bottom-up self-assembly approach to constructing ordered mesoporous nanofibers with a structure resembling vascular bundles via electrospinning. The synthesis involves self-assembling polystyrene（PS） homopolymer, amphiphilic diblock copolymer, and precursors into supramolecular micelles. Elongational dynamics of viscoelastic micelle solution together with fast solvent evaporation during electrospinning cause simultaneous close packing and uniaxial stretching of micelles, consequently producing polymer nanofibers consisting of oriented micelles. The method is versatile for the fabrication of large-scale ordered mesoporous nanofibers with adjustable pore diameter and various compositions such as carbon, SiO2, TiO2and WO3. The aligned longitudinal mesopores connected side-by-side by tiny pores offer highly exposed active sites and expedite electron/ion transport. The assembled electrodes deliver outstanding performance for lithium metal batteries.

关键词： ordered mesoporous nanofibers electrospinning oriented micelles lithium metal batteries

Consensus on rapid screening for prodromal Alzheimer's disease in China

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General Psychiatry 2024年第1期37卷 1-16页

作者： lin Huang Qinjie Li Yao Lu Fengfeng Pan Liang Cui Ying Wang Ya Miao Tianlu Chen Yatian Li Jingnan Wu Xiaochun Chen jianping Jia Qihao Guo Department of Gerontology Shanghai Sixth People's Hospital Afiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina Center for Translational Medicine and Shanghai Key Laboratory of Diabetes Mellitus Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina shanghai BestCovered ShanghaiChina ADepartment of Neurology Fujan Medical University Union HospitalFuzhouChina Department of Neurology National Clinical Research Center for Geriatric DiseasesBeijingChina

Alzheimer's disease(AD)is a common cause of dementia,characterised by cerebral amyloid-βdeposition,pathological tau and *** prodromal stage of AD(pAD)refers to patients with mild cognitive impairment(MCl)and evidence of AD's *** this stage,disease-modifying interventions should be used to prevent the progression to *** the inherent heterogeneity of MCl,more specific biomarkers are needed to elucidate the underlying AD's *** the uses of cerebrospinal fluid and positron emission tomography are widely accepted methods for detecting AD's pathology,their clinical applications are limited by their high costs and invasiveness,particularly in low-income areas in ***,to improve the early detection of Alzheimer's disease(AD)pathology through cost-effective screening methods,a panel of 45neurologists,psychiatrists andgerontologistswas invited to establish a formal consensus on the screening of pAD in *** supportive evidence and grades of recommendations are based on a systematic literature review andfocus group *** meetings were held to allow participants to review,vote and provide their expert opinions to reach a consensus.A majority(two-thirds)decision was used for questions for which consensus could not be *** screening methods are presented in this publication,including neuropsychological assessment,peripheral biomarkers and brain *** addition,a general workflow for Screening pAD in China is established,which will help clinicians identify individuals at high risk and determine therapeutic targets.

关键词： Alzheimer income screening

激光烧蚀铝合金表面对其胶接接头耐腐蚀性能的影响

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中国机械工程 2017年第23期28卷 2893-2897页

作者：朱传敏吕珊珊梅雨林建平同济大学机械与能源工程学院上海201804 同济大学上海市地面交通工具空气动力与热环境模拟重点实验室上海201804

采用激光对5052铝合金进行表面烧蚀处理,对其表面物化特性进行观察分析,并测试了其胶接接头在盐雾环境腐蚀后的剪切强度与失效模式。实验结果发现,经激光表面处理后,接头的剩余强度在盐雾环境腐蚀后强度增大了40%,并且失效模式由几乎完... 详细信息

采用激光对5052铝合金进行表面烧蚀处理,对其表面物化特性进行观察分析,并测试了其胶接接头在盐雾环境腐蚀后的剪切强度与失效模式。实验结果发现,经激光表面处理后,接头的剩余强度在盐雾环境腐蚀后强度增大了40%,并且失效模式由几乎完全界面失效变成内聚失效。经分析测量,处理后的铝合金表面粗糙度从0.09μm增大到1.77μm,并且在其表面形成了凹凸不平的多孔结构,胶接时发现胶粘剂渗入其中增强了胶接界面的粘接;同时,经过表面元素能谱分析,发现氧元素含量增加,铝合金表面生成氧化铝,也有利于增强铝合金基体的抗腐蚀性能,证明激光表面处理可以提高胶接接头的耐腐蚀性能。

关键词：铝合金激光烧蚀胶接接头耐腐蚀性能