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Relation Between the Eventual Continuity and the E-property for Markov-Feller Semigroups

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 1-16页

作者： Yong liu zi-yu liu LMAM School of Mathematical SciencePeking UniversityBeijing100871China

We investigate some relations between two kinds of semigroup regularities, namely the e-property and the eventual continuity, both of which contribute to the ergodicity for Markov processes on Polish *** precisely, we prove that for Markov-Feller semigroup in discrete time and stochastically continuous MarkovFeller semigroup in continuous time, if there exists an ergodic measure whose support has a nonempty interior,then the e-property is satisfied on the interior of the support. In particular, it implies that, restricted on the support of each ergodic measure, the e-property and the eventual continuity are equivalent for the discrete-time and the stochastically continuous continuous-time Markov-Feller semigroups.

关键词： Markov-Feller semigroup ergodicity e-property eventual continuity

Palladium-catalyzed allylic alkylation enabled by ketone umpolung via Pudovik addition/[1,2]-phospha-Brook rearrangement

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Science China Chemistry 2023年第10期66卷 2810-2816页

作者： jian Zhang Jia-Yi Su Yang-zi liu Hao Li Quannan Wang Wei-Ping Deng College of Chemistry and Materials Science Zhejiang Normal UniversityJinhua 321004China School of Pharmacy East China University of Science and TechnologyShanghai 200237China

Palladium-catalyzed allylic alkylation enabled by ketone umpolung via Pudovik addition/[1,2]-phospha-Brook rearrangement with phosphites has been *** protocol offers a straightforward method for the synthesis of potentially bioactive homoallylic alcohol phosphonates in an efficient and economical *** cascade reaction proceeds under mild conditions with excellent functional group ***,the catalytic asymmetric version has also been explored.

关键词： palladium umpolung allylic alkylation Pudovik addition -phospha-Brook rearrangement

Enhanced switching electric field and breakdown strength of epoxy composites with core-shell silicon carbide nanoparticles

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High Voltage 2023年第3期8卷 583-589页

作者： Yongsen Han zi Wang jian Sun Zhonghua Li Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbinHeilongjiangChina

Silicon carbide(SiC)is widely used to improve the non-linear conductivity of non-linear resistive field grading *** this paper,the SiC nanoparticles are modified into core-shell nanoparticles with silica(SiO_(2))coating on the surface and are characterised by transmission electron microscopy and X-ray diffraction,*** 7 wt%SiC@SiO_(2)/epoxy nanocomposite is then prepared,and the pure epoxy and 7 wt%SiC/epoxy nanocomposite are prepared as a *** relative permittivity,thermally stimulated current,conductivity and breakdown strength are studied,*** presence of SiO_(2)shell around SiC nanoparticles has a great effect on the relative permittivity and trap *** epoxy nanocomposites show non-linear conductivity characteristics,compared with pure *** 7 wt%SiC@SiO_(2)/epoxy nanocomposite has higher switching electric field and breakdown strength than the 7 wt%SiC/epoxy nanocomposite,which is helpful for the application of non-linear resistive field grading composite in higher-voltage equipment or components.

关键词： nanoparticles composites composite

Experimental investigation on pressure-buildup characteristics of a water lump immerged in a molten lead pool

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Nuclear Science and Techniques 2023年第3期34卷 25-39页

作者： zi-jian Deng Song-Bai Cheng Hui Cheng Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

Motivated to understand the pressure-buildup characteristics in a circumstance of a water droplet immerged inside a heavy liquid metal pool,which is a key phenomenon during a Steam Generator Tube Rupture accident of Lead-cooled Fast Reactor,many experiments have been conducted by injecting water lumps into a molten lead pool at Sun Yat-sen *** order to deepen the understanding of the influence of melt material,this lead experiment was compared with a Lead-Bismuth-Eutectic(LBE)experiment in the *** both experiments,a steam explosion occurred in a small part of the experi-mental runs,which generally leads to strengthened pressure *** the non-explosion experimental cases,the impact of all parameters employed in lead experiments(i.e.,water lump volume,water lump shape,molten pool depth,and temperature of water and melt)on the pressure buildup is non-negligible and similar to that in our previous experiments using ***,limited pressure buildup with an increase in water lump volume was also observed.A slightly more violent pressure buildup tends to appear in the lead experiments than in the LBE experiments under the same experimental conditions,which may be due to the higher thermal conductivity of lead than of *** a few experimental runs with a relatively low melt temperature close to the melting point of lead,local solidification of liquid lead was observed,restricting pressure *** the lead and LBE experiments,the calculated melt kinetic energy conversion efficiencyηhas a relatively small value(not exceeding 1.6%),and theηvalues have an overall positive correlation with the impulse on the molten pool.

关键词： Lead-cooled fast reactor Steam generator tube rupture accident Pressure-buildup characteristics Experimental study Melt material

Assessment of mouse BMMNC DNA damage with a two-tailed comet assay after X-ray and carbon ion total body irradiation

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Nuclear Science and Techniques 2018年第6期29卷 1-8页

作者： Fang liu Zhuan-zi Wang Wen-jian Li Wei Wei Bing-Rong Dang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049China

The two-tailed comet assay(2T-comet assay) is a method for simultaneously evaluating DNA single-strand breaks(SSBs) and double-strand breaks(DSBs). In the present study, the endonuclease DNase I and hydrogen peroxide were used to induce DSBs and SSBs in bone marrow mononuclear cells(BMMNCs) from mice, and the damaged DNAs were assessed with a 2T-comet assay. The results demonstrated that this method can detect and discriminate between BMMNC DNA SSBs and DSBs simultaneously. Using this method, we studied DNA damage in BMMNCs from female BALB/c mice after total body irradiation with X-rays and carbon ions. The results indicated that these two types of radiation induced serious DNA damage in BMMNCs in a dose-dependent *** DNA damage induced by carbon ions was more severe than that induced by X-rays at the same dose, and a high dose of carbon ion radiation was more likely to cause death in mice. The DSBs and SSBs induced by X-rays were the highest on the 3rd day post-IR. For carbon ion radiation,DSBs were the most serious on the 3rd day, while SSBs were more obvious on the 3rd day and 13th day *** ratio of DSBs/SSBs was clearly related to the different types of radiation.

关键词： DNA 碳离子损坏彗星尾巴身体金鼠标

Prognostic value of c-Met in colorectal cancer:A metaanalysis

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World Journal of Gastroenterology 2015年第12期21卷 3706-3710页

作者： Yan liu Xiao-Feng Yu jian Zou zi-Hua Luo Department of Gastroenterology Huadong Hospital Fudan University

AIM: To assess the prognostic value of c-Met status in colorectal cancer. METHODS: We conducted a search in Pub Med, Web of Science, and the Cochrane Library covering all published papers up to July 2014. Only studies assessing survival in colorectal cancer by c-Met status were included. This meta-analysis was performed by using ***: Ultimately, 11 studies were included in this analysis. Meta-analysis of the hazard ratios(HR)indicated that patients with high c-Met expression have a significantly poorer overall survival(OR)(HR = 1.33, 95%CI: 1.06-1.59) and progression-free survival(PFS)(HR = 1.47, 95%CI: 1.03-1.91). Subgroup analysis showed a significant association between high c-Met expression and poorer overall survival in the hazard ratio reported(HR = 1.41, 95%CI: 1.08-1.74).CONCLUSION: The present meta-analysis indicated that high c-Met expression was associated with poor prognosis in patients with colorectal cancer.

关键词： Colorectal cancer Prognosis c-Met Metaanalysis Ove

人脐带间充质干细胞抑制脓毒症小鼠肺组织细胞的焦亡

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中国组织工程研究 2025年第31期29卷 6642-6648页

作者：何长良王炎罗玲刘坚中山市古镇人民医院呼吸与危重症医学科广东省中山市528400 湘潭市中心医院/湖南大学附属医院综合ICU 湖南省湘潭市411100

背景:急性肺损伤是脓毒症患者的常见严重并发症,其发病机制复杂,目前尚无有效的药物治疗方案。人脐带间充质干细胞通过抑制细胞过度焦亡从而改善脓毒症急性肺损伤的作用机制愈发受到重视。目的:探索人脐带间充质干细胞对脓毒症所致急性... 详细信息

背景:急性肺损伤是脓毒症患者的常见严重并发症,其发病机制复杂,目前尚无有效的药物治疗方案。人脐带间充质干细胞通过抑制细胞过度焦亡从而改善脓毒症急性肺损伤的作用机制愈发受到重视。目的:探索人脐带间充质干细胞对脓毒症所致急性肺损伤小鼠肺组织细胞焦亡的影响及机制。方法:48只Balb/c雄性小鼠按随机数字法分为假手术组、模型组、治疗组(n=16)。模型组、治疗组行盲肠结扎穿孔建立脓毒症所致急性肺损伤模型,假手术组仅开腹后缝合。治疗组术后6 h尾静脉注射200μL人脐带间充质干细胞悬液(5×105个细胞),模型组及假手术组术后6 h尾静脉注射200μL生理盐水。术后28 h,各组随机取5只小鼠予以尾静脉注射伊文思蓝检测肺血管通透性;收集各组剩余小鼠肺泡灌洗液和肺组织,ELISA检测肺泡灌洗液中白细胞介素1β、白细胞介素18水平,计数肺泡灌洗液中细胞总数及巨噬细胞数;苏木精-伊红染色观察肺组织病理学形态,TUNEL染色观察肺组织细胞焦亡情况,RT-PCR、Western blot检测肺组织中Toll样受体4、GSDMD及Caspase-11的mRNA和蛋白表达。结果与结论:与模型组相比,治疗组术后28 h肺血管通透性显著下降(P<0.05),肺泡灌洗液中白细胞介素1β、白细胞介素18水平降低(P<0.05),细胞总数及巨噬细胞数降低(P<0.05),肺损伤程度减轻,肺组织细胞焦亡指数降低(P<0.05),肺组织Toll样受体4、GSDMD、GSDMD-N及Caspase-11 mRNA及蛋白表达水平均显著下降(P<0.05)。结果表明,人脐带间充质干细胞可能通过抑制Toll样受体4/Caspase-11/GSDMD信号通路活化,改善肺组织细胞焦亡,从而在一定程度上改善脓毒症小鼠肺损伤的严重程度。

关键词：人脐带间充质干细胞 Toll样受体4 Caspase-11 GSDMD 急性肺损伤急性呼吸窘迫综合征细胞焦亡脓毒症工程化干细胞

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What Caused the Inconsistency between Rb-Sr and^(40)Ar-^(39)Ar Ages of Authigenic Illites?

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Journal of Earth Science 2022年第5期33卷 1145-1151页

作者： Entao liu I.Tonguc Uysal jian-Xin Zhao zi'ao Zhang Xudong Lin Hubei Key Laboratory of Marine Geological Resources China University of GeosciencesWuhan 430074China Radiogenic Isotope Facility School of Earth and Environmental SciencesThe University of QueenslandBrisbaneQld4072Australia Department of Geological Engineering Istanbul University-CerrahpaşaIstanbul34098Turkey

Radiogenic isotope dating of illitic clays has been widely used to reconstruct thermal and fluid flow events in siliciclastic sedimentary basins,the information of which is critical to investigate mechanisms of hydrocarbon *** study carried out Rb-Sr and^(40)Ar-^(39)Ar dating of authigenic illitic clay samples separated from the Palaeogene sandstone in the northern South China *** Rb-Sr data further confirm the previously reported three periods of fluid flow events(at 34.5±0.9,31.2±0.6,and 23.6±0.8 Ma,respectively)in the northern South China Sea,which are related to regional episodic ***,^(40)Ar-^(39)Ar ages of illite obtained in this study are significantly younger than the corresponding Rb-Sr *** significantly younger^(40)Ar-^(39)Ar ages were probably due to ^(40)Ar loss caused by later dry heating events on the Hainan Island that have not affected the Rb-Sr isotopic *** inconsistency between Rb-Sr and^(40)Ar-^(39)Ar data should be attributed to different isotopic behaviors of K-Ar and Rb-Sr isotopic systematics in *** results indicate that Rb-Sr isotopic dating method may be a preferential approach for clay dating in geological settings where exist younger dry heating events.

关键词： authigenic illite isotope dating Rb−Sr isochron ^(40)Ar-^(39)Ar dating inconsistency geochemistry

Defect engineering of hierarchical porous carbon microspheres for potassium-ion storage

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Rare Metals 2022年第10期41卷 3446-3455页

作者： Xin-Fei Wu zi-jian Li Jin-Xiao liu Wen Luo Jean-Jacques Gaumet Li-Qiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China Department of Physics School of ScienceWuhan University of TechnologyWuhan430070China Laboratoire de Chimie et Physique:Approche Multi-échelles des Milieux Complexes(LCP-A2MC)Institut Jean BarriolUniversitéde LorraineMetz57070France

Owing to adjustable microstructure and stable physiochemical properties,carbon-based materials are regarded as promising materials as anodes for potassium-ion batteries(PlBs).Building amorphous structure and introducing defects are favorable methods to generate active sites and improve the electrochemical performances of carbon-based *** this work,we develop a facile carbonization method to prepare sulfur-doped amorphous carbon microspheres with hierarchical structure and modulated defects concentration(S-CM-700) for potassium *** from the special microstructure,S-CM-700 exhibits the optimal performance and obtains high reversible capacity of 199.6 mAh·g^(-1) at 100 mA·g^(-1),excellent rate property and prominent durability(0.0055%capacity decay per cycle during 1800 cycles).Kinetics analysis and electrochemical characterization are carried out to reveal that the potassium storage could be boosted by regulating the defect level,layer spacing and the content of *** work provides a general synthesis approach to prepare sustainable carbon anodes for advanced PlBs.

关键词： Potassium-ion battery(PIB) Defect engineering Amorphous carbon Hierarchical structure Anode