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SOURCES OF FOREIGN LANGUAGE ANXIETY:TOWARDS A FOUR-DIMENSION MODEL

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当代外语研究 2012年第12期384卷 49-61页

作者： han luo Northwestern University

In the past three decades,the study of foreign language anxiety has attracted the attention of an increasing number of researchers and language *** in a variety of language learning contexts have found that approximately one-third of students studying a foreign language experience at least a moderate level of foreign language *** has also reported various types of negative effects of foreign language anxiety on foreign language *** foreign language anxiety is not only prevalent among language learners,but appears to interfere with language learning,it must be taken seriously in all types of language *** language teachers are interested in the causes of foreign language anxiety so that they can create more comfortable language learning *** sources of foreign language anxiety have been identified here and there across the literature,there has not been a systematic and comprehensive report of all the *** paper attempts to propose a four-dimension source model of foreign language anxiety based on a thorough literature review and the researcher' s own insights.

关键词：英语教学教学方法课堂教学阅读教学

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污泥处理与资源化虚拟仿真实验的设计与实践

造纸技术与应用 2024年第2期52卷 60-65页

作者：罗邯予李正朴海燕张兰河张庭东北电力大学化学工程学院吉林吉林132012

阐述了污泥处理与资源化虚拟仿真实验体系的设计背景、构建、实验环境及教学效果。针对好氧发酵和脱水焚烧工艺建立了虚拟仿真模块。学生操作具体分为构建工艺路线、设计计算、运行与调试仿真实验、提交操作4部分。虚拟仿真实验可以使... 详细信息

阐述了污泥处理与资源化虚拟仿真实验体系的设计背景、构建、实验环境及教学效果。针对好氧发酵和脱水焚烧工艺建立了虚拟仿真模块。学生操作具体分为构建工艺路线、设计计算、运行与调试仿真实验、提交操作4部分。虚拟仿真实验可以使学生熟悉好氧发酵和脱水焚烧工艺相关的基础知识、主要设备及工艺流程,弥补实体实验的不足。

关键词：污泥资源化利用虚拟仿真固体废物环境工程

Review on the plastic instability of medium -Mn steels for identifying the formation mechanisms of Lüders and Portevin -Le Chatelier bands

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1285-1297页

作者： Bin Hu han Sui Qinghua Wen Zheng Wang Alexander Gramlich Haiwen luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Steel Institute RWTH Aachen UniversityIntzestraße 152072 AachenGermany

Plastic instability,including both the discontinuous yielding and stress serrations,has been frequently observed during the tensile deformation of medium-Mn steels(MMnS)and has been intensively studied in recent ***,research results are controversial,and no consensus has been achieved regarding the ***,we first summarize all the possible factors that affect the yielding and flow stress serrations in MMnS,including the morphology and stability of austenite,the feature of the phase interface,and the deformation ***,we propose a universal mechanism to explain the conflicting experimental *** conclude that the discontinuous yielding can be attributed to the lack of mobile dislocation before deformation and the rapid dislocation multiplication at the beginning of plastic ***,the results show that the stress serrations are formed due to the pinning and depinning between dislocations and interstitial atoms in ***-induced martensitic transformation,influenced by the mechanical stability of austenite grain and deformation parameters,should not be the intrinsic cause of plastic ***,it can intensify or weaken the discontinuous yielding and the stress serrations by affecting the mobility and density of dislocations,as well as the interaction between the interstitial atoms and dislocations in austenite grains.

关键词： medium manganese steel discontinuous yielding stress serrations retained austenite dislocations

Effect of Zirconium on Tensile Property,Microstructure and Fracture Behaviour of Cast Ni_(3)Al Based Alloy

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Journal of Iron and Steel Research International 1997年第1期4卷 37-41页

作者： Ye Wujun, Feng Di, han Guangwei, luo Heli Central Iron and Steel Research Institute, MMI, Beijing (100081), China Ctrl. Iron and Stl. Res. Institute MMI Beijing 100081 China

The effect of Zr on tensile property, microstructure and fracture behaviour of cast Ni 3Al based alloy strengthened with carbides has been studied. It was found that Zr distributes at interdendrites and grain boundaries in the form of ZrC particle and Ni 5Zr eutectic phase which can refine microstructure. Ni 5Zr phase can alleviate the crack initiation at grain boundaries and dendrite boundaries, which helps deformation to be harmonical between matrix and precipitates at elevated temperature.

关键词： Ni 3Al alloy tensile property fracture behaviour microstructure

Counting of alpha particle tracks on imaging plate based on a convolutional neural network

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Nuclear Science and Techniques 2023年第3期34卷 52-63页

作者： Feng-Di Qin han-Yu luo Zheng-Zhong He Ke-Jun Lu Chuan-Gao Wang Meng-Meng Wu Zhong-Kai Fan Jian Shan School of Nuclear Science and Technology Hunan Provincial Key Laboratory of RadonUniversity of South ChinaHengyang 421001China School of Computer Science University of South ChinaHengyang 421001China China Institute of Atomic Energy Beijing 102413China

Imaging plates are widely used to detect alpha particles to track information,and the number of alpha particle tracks is affected by the overlapping and fading effects of the track *** this study,an experiment and a simulation were used to calibrate the efficiency parameter of an imaging plate,which was used to calculate the *** were created by using grayscale,which trained the convolutional neural network to count the alpha *** results demonstrated that the trained convolutional neural network can evaluate the alpha track counts based on the source and background images with a wider linear range,which was unaffected by the overlapping *** alpha track counts were unaffected by the fading effect within 60 min,where the calibrated formula for the fading effect was analyzed for 132.7 *** detection efficiency of the trained convolutional neural network for inhomogeneous ^(241)Am sources(2π emission)was 0.6050±0.0399,whereas the efficiency curve of the photo-stimulated luminescence method was lower than that of the trained convolutional neural network.

关键词： Imaging plate Convolutional neural network Alpha tracks counting

Acid-catalyzed ring-expansion of 4-(1-hydroxycyclobutyl)-1,2,3-triazoles

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Organic Chemistry Frontiers 2022年第4期9卷 1065-1069页

作者： Mingchuan Xu Lei Liu Tao Wang han luo Meili Hou Luan Du Xiaolan Xin Qixing Lu Baosheng Li School of Chemistry and Chemical Engineering Chongqing University174 Shazheng StreetChongqing400044P.R.China

We here report a direct ring-opening/semipinacol rearrangement reaction of 4-(1-hydroxycyclobutyl)-1,2,3-triazole,in which N-acyl substituted 1,2,3-triazole was generated in situ and would trigger thermo-dynamically controlled electrocyclization ring-opening to afford a rearrangement precursor(α-diazo-ol).This strategy avoided the usage of metal catalysts and the reservation of sulfonyl groups on the N^(1)-posi-tion of 1,2,*** final cycloenaminone product is highly reactive and could be commonly used as a dinucleophilic acceptor to synthesize structurally diverse fused bicyclic products.

关键词： triazole rearrangement catalyzed

水杨醛席夫碱类聚集诱导发光分子的制备、表征及应用研究

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化学教育（中英文） 2024年第10期45卷 36-42页

作者：罗寒非阿克加依·哈尔肯别克刘迪炯胥艳子张雯党东锋西安交通大学化学学院陕西西安710049

现有实验教学中使用的醛胺缩合反应普遍存在反应时间长、反应程度低及制备过程略微复杂等问题,阻碍了该类实验在本科教学中的开展,影响了相关知识点的生动呈现。同时,现有实验主要围绕亚胺的合成过程进行教学,较少探究物质的功能特性,... 详细信息

现有实验教学中使用的醛胺缩合反应普遍存在反应时间长、反应程度低及制备过程略微复杂等问题,阻碍了该类实验在本科教学中的开展,影响了相关知识点的生动呈现。同时,现有实验主要围绕亚胺的合成过程进行教学,较少探究物质的功能特性,导致其实验设计在性能测试及应用呈现上存在一定的限制。针对上述问题,通过选择合适的反应底物,介绍了2种简单绿色的席夫碱实验合成方法,有效优化了相关实验内容,简化了实验过程,利于结合醛胺缩合等相关知识点进行本科教学实验的开发设计。此外,也结合“聚集诱导发光”这一国人引领的前沿研究领域,以席夫碱的合成反应为切入点,促进学生更好地了解国际学术发展前沿,激发学生学习兴趣,开拓学生科研视野。同时,根据不同层次的教学需求,本实验还可进一步引入核磁共振波谱、高分辨质谱、紫外吸收光谱以及荧光发射光谱等多种表征方法,为全面提高学生的综合实验素养提供支撑。

关键词：聚集诱导发光水杨醛席夫碱化学实验改进与创新

Applications of human amniotic fluid stem cells in wound healing

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Chinese Medical Journal 2022年第19期135卷 2272-2281页

作者： han luo Zhen Wang Fang Qi Dali Wang Department of Plastic Surgery and Burns The Affliated Hospital of Zunyl Medical UniversityZunylGuizhou 563003China Department of Plastic Surgery and Burns Fuling Central HospitalChongqing 408000China

Complete wound regeneration preserves skin structure and physiological functions,including sensation and perception of stimuli,whereas incomplete wound regeneration results in fibrosis and *** fluid stem cells(AFSCs)would be a kind of cell population with self-renewing and non-immunogenic ability that have a considerable role in wound *** are easy to harvest,culture,and store;moreover,they are non-tumorigenic and not subject to ethical *** can differentiate into different kinds of cells that replenish the skin,subcutaneous tissues,and accessory ***,AFSCs independently produce paracrine effectors and secrete them in exosomes,thereby modulating local immune cell *** demonstrate anti-inflammatory and immunomodulatory properties,regulate the physicochemical microenvironment of the wound,and promote full wound ***,AFSCs are potential resources in stem cell therapy,especially in scar-free wound *** review describes the biological characteristics and clinical applications of AFSCs in treating wounds and provide new ideas for the treatment of wound healing.

关键词： Amniotic fluid Stem cells Mesenchymal stromal cells Wound healing Cicatrix Hypertrophic Tissue engineering

A high performance frequency offset estimator for OFDM

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 2104-2109页

作者： WU Yun luo han-wen DING Ming YAN Chong-guang Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Sharp Advaneed R＆D Centre Sharp Electronics Co. Ltd Shanghai 201206 China

This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble is designed, which is composed of one regular OFDM training block with even numbers of identical parts and one irregular OFDM training block with odd numbers of identical parts. The initial estimates obtained over the two training blocks are next exploited to jointly estimate the CFO. By elaborately selecting the numbers of identical parts for the two training blocks, the proposed CFO estimator can estimate frequency offset over tens of the subcarrier spacing. Simulation results showed that the proposed CFO estimator satisfies the estimate range requirement for the practical OFDM systems, while achieving a very good estimate performance.

关键词： OFDM Frequency offset estimation Preamble Chinese residues theorem