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Recrystallization nucleation under close-setδphase in a nickel-based superalloy during annealing

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Journal of Materials Science & Technology 2022年第20期115卷 166-176页

作者： Guanqiang Wang mingsong chen Yongcheng Lin Hongbin Li Yuqiang Jiang Yanyong Ma chengxu Peng Jinliang Cai Quan chen School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China Light Alloy Research Institute Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Changsha 410083China College of metallurgies and energy North China University of Science and TechnologyTangshan 063009China

Annealing is one of the most efficient heat treatment to refine the grain microstructure in metal alloys.Prior to the annealing,an aging treatment can be implemented to precipitate the second phases for more nucleation sites in deformed mixed grains during subsequent recrystallization.However,the underlying mechanism behind the second phases and recrystallization has not yet been fully understood.Taking a typical deformed nickel(Ni)-based(GH4169)superalloy as an exapmle,this research aims to clairfy the connections between the recrystallization and delta(δ)phase(Ni_(3)Nb) during annealing.All deformed samples were also treated by aging and then annealing.The results show that the microstructure and component ofδphase dominated the recrystallization nucleation in the Ni-based alloy.Moreover,there was the presence of theδphase interval limiting nucleation(PILN)andδphase protecting nucleation(PPN),when a high content of close-set phase was precipitated from the matrix.The PILN determined the primary condition for the recrystallization nucleation that happended at the interval ofδphase larger than the critical nucleation size.The peak nucleation occurred in the PPN,where the recrystallization nucleus were free of the penetration by the adjacent grains,before the nucleation incubation time was reached.Thus,a new feasible JNtheory was proposed to determine the maximum domain of recrystallization nucleation under close-set precipitated phases.All the possible nucleation sites were assumed under PPN in the JNtheory.As such,the original microstructure can be expected to design for the annealing via the aging process.A quantitative evaluation of recrystallization nucleation can also achieved in the Ni-based alloys during aging.

关键词： Nickel-based superalloy δphase Recrystallization Nucleation Metal alloys

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Development and validation of a novel criterion of histologic healing in ulcerative colitis defined by inflammatory cell enumeration in lamina propria mucosa: A multicenter retrospective cohort in China

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中华医学杂志(英文版) 2024年第11期137卷 2024 May 13页

作者： Gao Han Peng Kangsheng Shi Yadi Zhu Shenshen Sun Ruicong Xu Chunjin Liu Ping Pang Zhi Zhu Lanxiang chen Weichang Feng Baisui Wu Huili Zhou Guangxi Li mingsong Li Junxiang Ding Baijing Liu Zhanju Department of Gastroenterology The Third Affiliated Hospital of Guangzhou Medical University Guangzhou Guangdong China Department of Gastroenterology Dongfang Hospital of Beijing University of Chinese Medicine Beijing China Center for IBD Research and Department of Gastroenterology Shanghai Tenth People’s Hospital Tongji University School of Medicine Shanghai China Clinical Medicine Sanquan College of Xinxiang Medical University Xinxiang Henan China Department of Gastroenterology The First People’s Hospital of Shangqiu City Affiliated to Xinxiang Medical University Shangqiu Henan China Department of Gastroenterology Wuhu First People’s Hospital Wuhu Anhui China Department of Gastroenterology Suzhou Municipal Hospital Affiliated to Nanjing Medical University Suzhou Jiangsu China Department of Gastroenterology The First Affiliated Hospital of Soochow University Suzhou Jiangsu China Department of Gastroenterology The Second Affiliated Hospital of Zhengzhou University Zhengzhou Henan China Department of Gastroenterology Zhengzhou Central Hospital Affiliated to Zhengzhou University Zhengzhou Henan China Department of Gastroenterology The Affiliated Hospital of Jining Medical College Jining Shandong China

Background: Histological healing is closely associated with improved long-term clinical outcomes and lowered relapses in patients with ulcerative colitis (UC). Here, we developed a novel diagnostic criterion for assessing histological healing in UC patients.Methods: We conducted a retrospective cohort study in UC patients, whose treatment was iteratively optimized to achieve mucosal healing at Shanghai Tenth People’s Hospital of Tongji University from January 2017 to May 2022. We identified an inflammatory cell enumeration index (ICEI) for assessing histological healing based on the proportions of eosinophils, CD177+ neutrophils, and CD40L+ T cells in the colonic lamina propria under high power field (HPF), and the outcomes (risks of symptomatic relapses) of achieving histological remissionvs. persistent histological inflammation using Kaplan-Meier curves. Intrareader reliability and inter-reader reliability were evaluated by each reader. The relationships to the changes in the Nancy index and the Geboes score were also assessed for responsiveness. The ICEI was further validated in a new cohort of UC patients from other nine university hospitals.Results: We developed an ICEI for clinical diagnosis of histological healing, i.e., Y = 1.701X1 + 0.758X2 + 1.347X3 - 7.745 (X1, X2, and X3 represent the proportions of CD177+ neutrophils, eosinophils, and CD40L+ T cells, respectively, in the colonic lamina propria under HPF). The receiver operating characteristics curve (ROC) analysis revealed that Y <-0.391 was the cutoff value for the diagnosis of histological healing and that an area under the curve (AUC) was 0.942 (95% confidence interval [CI]: 0.905-0.979) with a sensitivity of 92.5% and a specificity of 83.6% (P <0.001). The intraclass correlation coefficient (ICC) for the intrareader reliability was 0.855 (95% CI: 0.781-0.909), and ICEI had good inter-reader reliability of 0.832 (95% CI: 0.748-0.894). During an 18-month follow-up, patients with histological healing had a substantially better outcome compared with

关键词： Ulcerative colitis Histological healing Inflammatory cell enumeration index Prognosis

A Soy Protein-Based Composite Film with a Hierarchical Structure Inspired by Nacre

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Journal of Renewable Materials 2022年第3期10卷 639-652页

作者： Yecheng Xu Chaojie Xu mingsong chen Jianzhang Li Ling Zeng Jing Luo Qiang Gao Sheldon Q.Shi Beijing Key Laboratory of Wood Science and Engineering&MOE Key Laboratory of Wooden Material Science and Application Beijing Forestry UniversityBeijing100083China Nanning SCISKY Waterborne Technologies Co. Ltd.Nanning530105China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing210037China College of Engineering Department of Mechanical and Energy EngineeringUniversity of NorthTexasDenton76207-7102USA

Soy protein-based composite film is a potential replacement for petroleum-based film with multipurpose applica-tions and cleaner production.It is difficult to improve both the tensile strength and toughness of a protein-based film without sacrificing its elongation.In this study,inspired by the hierarchical structure of nacre,a facile yet delicate strategy was developed to fabricate a novel bio-based film with excellent toughness and high strength.Triglycidylamine(TGA)crosslinked soy protein(SPI)as hard phase and thermoplastic polyurethane elastomer(TPU)as soft phase comprise an alternative lay-up hierarchical structure.The interface of these two phases is enhanced using triglycidylamine(TGA)surface-modified TPU(MTPU).The tensile strength of SPI/MTPU/TGA films increases by 392%to 7.78 MPa and their toughness increases by 391%to 8.50 MJ/m^(3) compared to soy protein/glycerol film.The proposed hierarchical structure can also be extended to other high-performance materials and polymers.

关键词： Soy protein-based composite film hierarchical structure TPU enhancement mechanism

A proof-based method of hybrid systems development using differential invariants

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Frontiers of Computer Science 2018年第5期12卷 1026-1028页

作者： Jie LIU Jing LIU Miaomiao ZHANG Haiying SUN Xiaohong chen Dehui DU mingsong chen Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai 200062 China School of Computer Science and Technology University of South China HengYang 421001 China School of Software Engineering Tongji University Shanghai 201804 China

1 Introduction Event-B is a widely applied and proof-based language for incremental development via refinement [1]. Hybrid systems exhibit hybrid characteristics of discrete control and real-time continuous behaviors. However, Event-B is a discrete modeling language. It does not support the development of hybrid systems. So, the researchers are currently trying to make the extension of Event-B for the refinement development of hybrid systems [2, 3].

关键词：

A novel requirement analysis approach for periodic control systems

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Frontiers of Computer Science 2013年第2期7卷 214-235页

作者： Zheng WANG Geguang PU Jiangwen LI Yuxiang chen Yongxin ZHAO mingsong chen Bin GU Mengfei YANG Jifeng HE Shanghai Key Laboratory of Trustworthy Computing Software Engineering Institute East China Normal UniversityChina Shanghai 200241 Beijing Institute of Control Engineering China Beijing 100080 School of Computing National University of SingaporeSingapore Singapore 119077 China Academy of Space Technology China Beijing 100094

Periodic control systems （PCSs） are widely used in real-time embedded system domain. However, traditional manual requirement analysis assumes the expert knowledge, which is laborious and error-prone. This paper proposes a novel requirement analysis approach, which supports the automated validation of the informal requirement specifi- cations. Based on the normalized initial requirement docu- ments, our approach can construct an intermediate SPARDL model with both formal syntax and semantics. To check the overall system behaviors, our approach can transform the SPARDL models into executable code for simulation. The derived prototype simulator from SPARDL models enables the testing-based system behavior validation. Moreover, our approach enables the analysis of the dataflow relations in SPARDL models. By revealing input/output and affecting re- lations, our dataflow analysis techniques can help software engineers to figure out the potential data dependencies be- tween SPARDL modules. This is very useful for the module reuse when a new version of the system is developed. A study of our approach using an industry design demonstrates the practicality and effectiveness of our approach.

关键词： SPARDL simulation dataflow analysis codegeneration

控制棒驱动机构楔形迷宫密封组件设计与密封性能研究

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机电工程 2024年第4期41卷 666-673页

作者：武铭松魏世军李征姜楚华陈俊华谭杨宁波大学机械工程与力学学院浙江宁波315211 宁波天生密封件有限公司浙江宁波315302 宁波大学科学技术学院浙江宁波315300

控制棒驱动机构(CRDM)与压力容器管座之间通常采用焊接连接,针对堆芯换料导致的拆卸不便以及二次焊接时密封性能变差等问题,对控制棒驱动机构的连接形式进行了研究,提出了一种便于维修和利于拆卸的楔形迷宫密封结构。首先,引入了迷宫密... 详细信息

控制棒驱动机构(CRDM)与压力容器管座之间通常采用焊接连接,针对堆芯换料导致的拆卸不便以及二次焊接时密封性能变差等问题,对控制棒驱动机构的连接形式进行了研究,提出了一种便于维修和利于拆卸的楔形迷宫密封结构。首先,引入了迷宫密封的设计理念,加入了楔形密封结构,采用钢制压力容器的设计标准,计算了工况下控制棒驱动机构所需的最小壁厚和热压载荷耦合作用下的临界屈服温度;然后,应用有限元方法模拟了C形环工作状态,研究了金属C形环的回弹特性及密封面状态;最后,针对楔形迷宫密封组件开展了泄漏率试验和热循环试验。研究结果表明:工况下的最小壁厚为10 mm,临界屈服温度为72.5℃;C形环尺寸越大,最大线比压值越小,密封面的贴合程度越高;楔形迷宫密封组件的泄露率小于1.0×10-6 Pa·m 3/s,能够满足多次拆卸工况下的密封要求。

关键词：控制棒驱动机构楔形迷宫密封可拆卸密封结构密封性能泄露率最小壁厚临界屈服温度

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旋转生物反应器内球形体培养对人胎盘间充质干细胞炎症因子分泌的影响

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中国组织工程研究 2024年第19期28卷 3012-3017页

作者：张萍萍梁婷婷范明松陈黎张世昌南京医科大学第一附属医院检验学部江苏省南京市210029 南京医科大学第一附属医院产科江苏省南京市210029 南方医科大学深圳医院妇产科广东省深圳市518110 南方医科大学深圳医院检验科广东省深圳市518110

背景:生物反应器内球形体培养是既能维持间充质干细胞干性又能大规模扩增的体外培养方法,明确其对干细胞免疫调节作用的影响有利于指导临床应用。目的:探讨旋转生物反应器内球形体培养对人胎盘间充质干细胞炎症因子分泌的影响。方法:从... 详细信息

背景:生物反应器内球形体培养是既能维持间充质干细胞干性又能大规模扩增的体外培养方法,明确其对干细胞免疫调节作用的影响有利于指导临床应用。目的:探讨旋转生物反应器内球形体培养对人胎盘间充质干细胞炎症因子分泌的影响。方法:从人胎盘组织中分离培养人胎盘间充质干细胞,分别进行二维培养和旋转生物反应器培养,利用倒置相差显微镜、免疫组化染色和CCK-8实验观察细胞形态与增殖能力,RT-qPCR和流式荧光法检测多种炎症因子基因表达与蛋白分泌量。结果与结论:①旋转生物反应器内培养的人胎盘间充质干细胞聚集成多细胞球形体,数量与体积逐渐增加;②苏木精-伊红染色可见旋转生物反应器内培养4 d的人胎盘间充质干细胞在球形体内分布均匀,形态正常;③免疫组化染色显示球形体内有大量人胎盘间充质干细胞的细胞核Ki-67阳性;④CCK-8实验结果显示,生物反应器内球形体培养的人胎盘间充质干细胞活力显著高于二维培养的细胞;⑤RT-qPCR和流式免疫荧光法检测结果显示,旋转生物反应器内球形体培养的人胎盘间充质干细胞中白细胞介素1β、白细胞介素4、白细胞介素6、白细胞介素8、白细胞介素10、白细胞介素17、肿瘤坏死因子α和干扰素α的基因表达量和蛋白分泌量显著高于二维培养的细胞;⑥结果表明,旋转生物反应器内球形体培养能显著提高人胎盘间充质干细胞分泌多种炎症因子的能力,加强人胎盘间充质干细胞的免疫调节作用。

关键词：胎盘间充质干细胞生物反应器球形体炎症因子免疫调节

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颅内移植人骨髓间充质干细胞减轻大鼠脑缺血再灌注损伤

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中国组织工程研究 2024年第31期28卷 5036-5041页

作者：宋文学廖益东明江何龙才陈光唐陈晨王梓力熊明松崔君拴徐卡娅贵州医科大学贵州医科大学附属医院神经外科贵州医科大学附属医院高压氧科

背景：研究发现激活Nrf2/HO-1通路可减轻脑缺血再灌注损伤引起的氧化应激，但人骨髓间充质干细胞(humanbonemarrow mesenchymal stem cells,hBMSC)是否可激活Nrf2/HO-1通路减轻脑缺血再灌注损伤目前尚缺乏相关研究。目的：探讨颅内移植h... 详细信息

背景：研究发现激活Nrf2/HO-1通路可减轻脑缺血再灌注损伤引起的氧化应激，但人骨髓间充质干细胞(humanbonemarrow mesenchymal stem cells,hBMSC)是否可激活Nrf2/HO-1通路减轻脑缺血再灌注损伤目前尚缺乏相关研究。目的：探讨颅内移植hBMSC是否通过激活Nrf2/HO-1途径减轻脑缺血再灌注模型大鼠的氧化应激损伤。方法：40只雄性SPF级SD大鼠随机分为假手术组、模型组、hBMSC移植组、hBMSC+溶剂组和hBMSC+Nrf2抑制剂组，每组8只。模型组、hBMSC移植组通过线栓法制备大脑中动脉栓塞模型，1h后取出线栓，将30μL PBS或培养至5代以后的hBMSC注入大鼠右侧皮质及纹状体内；hBMSC+Nrf2抑制剂组和hBMSC+溶剂组在造模前24 h于左侧脑室分别注射Nrf2抑制剂Brusatol或其溶剂二甲基亚砜，然后制备大脑中动脉栓塞模型，注射hBMSC。移植后3 d进行相关指标检测。结果与结论：(1)脑CT和TTC染色显示脑梗死灶面积和体积一致：模型组> hBMSC+Nrf2抑制剂组> hBMSC+溶剂组> hBMSC移植组>假手术组；(2)苏木精-伊红染色和尼氏染色显示，假手术组缺血侧脑组织形态完好和神经元正常；模型组神经元排列结构紊乱和神经元损害严重；与模型组相比，hBMSC移植组、hBMSC+溶剂组病理形态和神经元损伤有较大的改善；与hBMSC+溶剂组相比，hBMSC+Nrf2抑制剂组病理形态和神经元损伤更严重；(3)Western blot和氧化应激指标检测结果显示，与假手术组相比，模型组Nrf2和HO-1蛋白表达降低(均P <0.05)，丙二醛升高而超氧化物歧化酶降低(均P <0.05)；与模型组相比，h BMSC移植组和h BMSC+溶剂组Nrf2、HO-1蛋白表达升高(均P <0.05)，丙二醛降低而超氧化物歧化酶升高(均P <0.05)；与hBMSC+溶剂组相比，hBMSC+Nrf2抑制剂组Nrf2和HO-1蛋白表达降低(均P <0.05)，丙二醛升高而超氧化物歧化酶降低(均P <0.05)；(4)上述结果表明，hBMSC可能通过激活Nrf2/HO-1途径减轻脑缺血再灌注氧化应激损伤。

关键词：人骨髓间充质干细胞脑缺血再灌注损伤氧化应激核因子E2相关因子2 血红素加氧化酶1

Real-Time Video Transmission of Visible Light Communication Based on LED

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International Journal of Communications, Network and System Sciences 2017年第8期10卷 58-68页

作者： mingsong chen Jie Guo Xiao Xu Minglan Liang School of Information and Communication Guilin University of Electronic Technology Guilin China

In order to realize the video image transmission and the excellent lighting function of the visible light communication system, a LED-based visible light communication method and system is proposed. Based on the field programmable gate array (FPGA) hardware, the RS channel coding is applied to the visible light communication system. A pulse position decision algorithm is proposed, which is applied to the receiver of the visible light communication system to meet the error-free decision of the signal. The design of the system is based on the analog-to-digital conversion circuit, which provides a large signal dynamic range for the pulse position decision algorithm, and designs the LED driver based on the bias circuit to realize the fast broadband modulation of the signal. The test results show that the combined application of pulse position decision algorithm and Reed-Solomon codec can reduce the error of system signal and meet the real-time and reliable transmission of signal. The system can display the received video in real time from the receiver, and the whole system communication distance up to 5 m.

关键词： Visible Light Communication LED Reed-Solomon Pulse Position Decision Video Transmission