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基于非牛顿流体的聚乙烯材料介观蠕变机制研究

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功能材料 2021年第10期52卷 10092-10097页

作者：刘铭徐献忠刘梦云李晨阳郑州大学力学与安全工程学院郑州450001

基于非牛顿流体Ostwald-de Waele方程和介观体系,提出了一种可用于分析聚乙烯材料蠕变特性的研究方法,探讨了聚乙烯材料的蠕变机制并对材料的微观形貌、力学性能和亲水性等进行了测试表征,验证了该研究方法的可行性。同时,利用稳态蠕变... 详细信息

基于非牛顿流体Ostwald-de Waele方程和介观体系,提出了一种可用于分析聚乙烯材料蠕变特性的研究方法,探讨了聚乙烯材料的蠕变机制并对材料的微观形貌、力学性能和亲水性等进行了测试表征,验证了该研究方法的可行性。同时,利用稳态蠕变本构方程与幂律流体的一致性对粘弹性材料进行了力学分析。结果表明,模型参数与非牛顿流体系数具有相似的物理意义,聚乙烯材料蠕变的主要变形机制为界面滑移产生的粘性变形,而应力松弛则为界面滑移、粘滞力和单元弹性的共同作用。使用基于稳态蠕变方程的应力松弛模型,对聚乙烯材料的应力松弛行为进行了分析,结合材料蠕变机制,提出了聚乙烯材料的介观松弛机制。

关键词：非牛顿流体聚乙烯材料介观蠕变机理应力松弛

ACBP4-WRKY70-RAP2.12 module positively regulates submergence-induced hypoxia response in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2024年第6期66卷 1052-1067页

作者： mengyun Guo Yingjun Yao Kangqun Yin† Luna Tan Meng liu Jing Hou Han Zhang Ruyun Liang Xinran Zhang Heng Yang Xiaoxiao Chen Jinrui Tan Yan Song Shangling Lou Liyang Chen Xuejing liu Si Tang Yongqi Hu Jin Yan Wensen Fu Kai Yang Ruijia Zhang Xuerui Li Yao liu Zhen Yan Wei liu Yu Han Jianquan liu Kangshan Mao Huanhuan liu Key Laboratory for Bio‐resources and Eco‐environment&State Key Lab of Hydraulics&Mountain River Engineering Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research StationKey Laboratory for Bio‐resource and Eco‐environment of Ministry of EducationCollege of Life SciencesSichuan UniversityChengdu 610065China

ACYL-CoA-BINDING PROTEINs(ACBPs)play crucial regulatory roles during plant response to hypoxia,but their molecular mechanisms remain poorly *** study reveals that ACBP4 serves as a positive regulator of the plant hypoxia response by interacting with WRKY70,influencing its nucleocytoplasmic shuttling in Arabidopsis ***,we demonstrate the direct binding of WRKY70 to the ACBP4 promoter,resulting in its upregulation and suggesting a positive feedback ***,we pinpointed a phosphorylation site at Ser638 of ACBP4,which enhances submergence tolerance,potentially by facilitating WRKY70's nuclear ***,a natural variation in this phosphorylation site of ACBP4 allowed *** to adapt to humid conditions during its historical demographic *** further observed that both phosphorylated ACBP4 and oleoyl-Co A can impede the interaction between ACBP4 and WRKY70,thus promoting WRKY70's nuclear ***,we found that the overexpression of orthologous Bna ***4and Bna ***70 in Brassica napus increases submergence tolerance,indicating their functional similarity across *** summary,our research not only sheds light on the functional significance of the ACBP4 gene in hypoxia response,but also underscores its potential utility in breeding flooding-tolerant oilseed rape varieties.

关键词： ACBP4 Arabidopsis thaliana humid adaptation natural variation RAP2.12 WRKY70

Across two phylogeographic breaks: Quaternary evolutionary history of a mountain aspen (Populus rotundifolia) in the Hengduan Mountains

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Plant Diversity 2024年第3期46卷 321-332页

作者： Jieshi Tang Xiaoyan Fan Richard I.Milne Heng Yang Wenjing Tao Xinran Zhang mengyun Guo Jialiang Li Kangshan Mao Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610065PR China Institute of Molecular Plant Sciences University of EdinburghEdinburgh EH93JHUK School of Ecology and Environment Tibet UniversityLhasa 850000PR China

Biogeographical barriers to gene flow are central to plant *** East Asia,plant distribution is greatly influenced by two phylogeographic breaks,the Mekong-Salween Divide and Tanaka-Kaiyong Line,however,few studies have investigated how these barriers affect the genetic diversity of species that are distributed across *** we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia,a species that spans both the Mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern *** and migration hypotheses were tested using coalescent-based *** historical gene flow was observed between the western and eastern groups of ***,but substantial flow occurred across both the Mekong-Salween Divide and Tanaka-Kaiyong Line,manifesting in clear admixture and high genetic diversity in the central ***-borne pollen and seeds may have facilitated the dispersal of *** following prevalent northwest winds in the *** also found that the Hengduan Mountains,where multiple genetic barriers were detected,acted on the whole as a barrier between the western and eastern groups of *** niche modeling suggested that *** has undergone range expansion since the last glacial maximum,and demographic reconstruction indicated an earlier population expansion around 600 *** phylogeographic pattern of *** reflects the interplay of biological traits,wind patterns,barriers,niche differentiation,and Quaternary climate *** study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas.

关键词： Chloroplast DNA Microsatellite Phylogeographic break Populus rotundifolia Quaternary history Wind direction

The DUF579 proteins GhIRX15s regulate cotton fiber development by interacting with proteins involved in xylan synthesis

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The Crop Journal 2024年第4期12卷 1112-1125页

作者： mengyun Li Feng Chen Jingwen Luo Yanan Gao Jinglong Cai Wei Zeng Monika S.Doblin Gengqing Huang Wenliang Xu Hubei Key Laboratory of Genetic Regulation and Integrative Biology School of Life SciencesCentral China Normal UniversityWuhan 430079HubeiChina Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation School of Life SciencesTaizhou UniversityTaizhou 318000ZhejiangChina La Trobe Institute for Sustainable Agriculture&Food School of AgricultureBiomedicine and EnvironmentLa Trobe UniversityBundooraVIC 3086Australia

Cotton provides the most abundant natural fiber for the textile *** mature cotton fiber largely consists of secondary cell walls with the highest proportion of cellulose and a small amount of hemicellulose and *** dissect the roles of hemicellulosic polysaccharides during fiber development,four IRREGULAR XYLEM 15(IRX15)genes,GhIRX15-1/-2/-3/-4,were functionally characterized in *** genes encode DUF579 domain-containing proteins,which are homologs of AtIRX15 involved in xylan *** four GhIRX15 genes were predominantly expressed during fiber secondary wall thickening,and the encoded proteins were localized to the Golgi *** GhIRX15 gene could restore the xylan deficient phenotype in the Arabidopsis irx15irx15l double *** of GhIRX15s in cotton resulted in shorter mature fibers with a thinner cell wall and reduced cellulose content as compared to the wild ***,GhIRX15-2 and GhIRX15-4 formed homodimers and *** addition,the GhIRX15s showed physical interaction with glycosyltransferases GhGT43C,GhGT47A and GhGT47B,which are responsible for synthesis of the xylan backbone and reducing end ***,the GhIRX15s can form heterocomplexes with enzymes involved in xylan modification and side chain synthesis,such as GhGUX1/2,GhGXM1/2 and *** findings suggest that GhIRX15s participate in fiber xylan biosynthesis and modulate fiber development via forming large multiprotein complexes.

关键词： Cotton fiber Xylan biosynthesis GhIRX15s Protein-protein interaction Protein complexes

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黄土高原南麓县域耕地土壤速效养分时空变异

生态学报 2013年第2期33卷 554-564页

作者：陈涛常庆瑞刘京齐雁冰刘梦云西北农林科技大学资源环境学院杨凌712100 农业部西北植物营养与农业环境重点实验室杨凌712100

在生态脆弱的黄土高原南麓合阳县,以1983、2006年耕地土壤速效氮、磷、钾含量为对象,利用空间自相关、变异函数及分形维数等方法,研究县域土壤速效养分时空变异特征及主要影响因素。结果表明,从1983到2006年,除土壤速效钾外,耕地速效氮... 详细信息

在生态脆弱的黄土高原南麓合阳县,以1983、2006年耕地土壤速效氮、磷、钾含量为对象,利用空间自相关、变异函数及分形维数等方法,研究县域土壤速效养分时空变异特征及主要影响因素。结果表明,从1983到2006年,除土壤速效钾外,耕地速效氮、磷的平均含量分别提高73.98%和92.69%;土壤速效养分全局Moran’s I指数和空间相关距均呈递减变化、分维数增加,预示其空间结构减弱,随机变异性增强。土壤速效氮、磷含量在绝大部分研究区域内呈现不同程度累积,而速效钾含量则在59.65%的耕地上减少;导致其不同变化的因素有耕地利用方式、施肥管理、灌溉、土壤类型等,其中以土地利用方式和施肥管理措施的影响最大。

关键词：土壤速效养分时空变异特征空间自相关变异函数分形维数

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基础刚度对框架墩地震响应的影响

高速铁路技术 2016年第5期7卷 16-19,24页

作者：刘孟云铁道第三勘察设计院集团有限公司天津300142

文章以京沈客专某跨线框架墩为研究对象,运用有限元软件Midas/civil建立框架墩的三维空间动力分析模型,研究了基础刚度对框架墩地震反应的影响。对该框架墩在0.5倍基础刚度、1倍基础刚度、2倍基础刚度、3倍基础刚度条件下分别进行多遇... 详细信息

文章以京沈客专某跨线框架墩为研究对象,运用有限元软件Midas/civil建立框架墩的三维空间动力分析模型,研究了基础刚度对框架墩地震反应的影响。对该框架墩在0.5倍基础刚度、1倍基础刚度、2倍基础刚度、3倍基础刚度条件下分别进行多遇地震作用下的弹性时程反应分析,分析基础刚度的变化对框架墩地震反应的影响并总结影响规律。结果表明:(1)框架墩的基础刚度对其自振特性影响显著,自振频率随着基础刚度的增大而增大;(2)基础刚度的变化对框架墩的地震响应影响显著,尤其是对框架墩墩柱的地震响应影响更加明显,其地震响应随着框架墩基础刚度的增加而增加;(3)框架墩的地震响应并不是随着基础刚度线性变化的,当基础刚度较小时框架墩的地震响应变化更明显。

关键词：框架墩基础刚度时程反应分析地震反应

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老字号品牌情感化设计策略研究及应用

品牌与标准化 2023年第S1期 22-26页

作者：刘孟昀湘潭大学艺术学院

随着市场竞争的激烈化，老字号品牌如何保持市场优势成了设计领域的研究热点。本文以湖南龙牌酱油为例，基于情感化设计三层次理论探讨情感化设计对老字号品牌的助推作用，并确立设计原则，通过对湖南龙牌酱油的文化背景和行业现状进行... 详细信息

随着市场竞争的激烈化，老字号品牌如何保持市场优势成了设计领域的研究热点。本文以湖南龙牌酱油为例，基于情感化设计三层次理论探讨情感化设计对老字号品牌的助推作用，并确立设计原则，通过对湖南龙牌酱油的文化背景和行业现状进行分析，结合情感化设计理论，探索龙牌酱油情感化设计创新思路，提出老字号品牌感官外形情感化、使用体验情感化、文化反思情感化三个层次的情感化设计策略，并以此为基础展开设计实践，以期为老字号品牌情感化设计提供新思路和实践参考，为老字号品牌创新设计注入新的活力和动力。

关键词：情感化设计三层次理论老字号品牌龙牌酱油

Leisure-time physical activity and all-cause mortality and cardiovascular disease in adults with type 2 diabetes:Cross-country comparison of cohort studies

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Journal of Sport and Health Science 2024年第2期13卷 212-221页

作者： Jakob Tarp mengyun Luo Miguel Adriano Sanchez-Lastra Knut Eirik Dalene Borja del Pozo Cruz Mathias Ried-Larsen Reimar Wernich Thomsen Ulf Ekelund Ding Ding Department of Clinical Epidemiology Aarhus University&Aarhus University HospitalAarhus 8200Denmark Prevention Research Collaboration Sydney School of Public HealthThe University of SydneyCamperdownNSW 2006Australia Charles Perkins Centre the University of SydneyCamperdownNSW 2050Australia Department of Sports Medicine Norwegian School of Sports SciencesOslo 0806Norway Department of Special Didactics Faculty of Education and Sports SciencesUniversity of VigoPontevedra 36005Spain Well-Move Research Group Galicia Sur Health Research Institute(IIS Galicia Sur)SERGAS-UVIGOVigo 36213Spain Department of Chronic Diseases Norwegian Institute of Public HealthOslo 0473Norway Centre for Active and Healthy Ageing Department of Sports Science and Clinical BiomechanicsUniversity of Southern DenmarkOdense 5230Denmark Faculty of Education University of CadizCadiz 11519Spain Biomedical Research and Innovation Institute of Cadiz(INiBICA)Research Unit Puerta del Mar University HospitalUniversity of CadizCadiz 11009Spain The Centre of Inflammation and Metabolism&the Centre for Physical Activity Research RigshospitaletUniversity of CopenhagenCopenhagen 2100Denmark Department of Sports Science and Clinical Biomechanics University of Southern DenmarkOdense 5230Denmark

Purpose:This study aimed to quantify the dose-response association and the minimal effective dose of leisure-time physical activity(PA)to prevent mortality and cardiovascular disease in adults with type 2 ***:Cross-country comparison of 2 prospective cohort studies including 14,913 and 17,457 population-based adults with type 2 diabetes from the UK and *** leisure-time PA was self-reported and categorized by metabolic equivalent hours per week(MET-h/week)according to World Health Organization recommendations:none,below recommendation(>0-7.49 MET-h/week);at recommended level(7.5-14.9 MET-h/week);above recommendation(>15 MET-h/week).Mortality and cardiovascular disease data were obtained from national ***:During a median follow-up of 12.4 and 9.7 years,in the UK and China cohorts,repectively,higher levels of leisure-time PA were inversely associated with all-cause(1571 and 2351 events)and cardiovascular mortality(392 and 1060 events),mostly consistent with a linear dose-response *** below,at,and above recommendations,compared with no activity,yielded all-cause mortality hazard ratios of0.94(95%confidence interval(95%CI):0.79-1.12),0.90(95%CI:0.74-1.10),and 0.85(95%CI:0.70-1.02)in British adults and 0.87(95%CI:0.68-1.10),0.88(95%CI:0.74-1.03),and 0.77(95%CI:0.70-0.85)in Chinese *** with cardiovascular mortality were more pronounced in British adults(0.80(95%CI:0.58-1.11),0.75(95%CI:0.52-1.09),and 0.69(95%CI:0.48-0.97))but less pronounced in Chinese adults(1.06(95%CI:0.76-1.47),1.01(95%CI:0.80-1.28),and 0.79(95%CI:0.69-0.92)).PA at recommended levels was not associated with lower rates of major adverse cardiovascular events(2345 and 4458 events).Conclusion:Leisure-time PA at the recommended levels was not convincingly associated with lower mortality and had no association with risk of major adverse cardiovascular events in British or Chinese adults with type 2 ***-time PA above current recom

关键词： Complications Epidemiology Exercise Prevention

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冷冻干燥制备聚酰亚胺气凝胶微观形态的调控

高分子材料科学与工程 2018年第9期34卷 115-119页

作者：彭黎莹王怡星吉剑奇刘梦云秦家强刘向阳四川大学高分子科学与工程学院高分子材料工程国家重点实验室四川成都610065

将一定浓度的水溶性聚酰胺酸盐(PAAS)溶液先通过冷冻干燥制备PAAS气凝胶,再经热酰亚胺化得到聚丙烯酰胺(PI)气凝胶。通过调控PAAS溶液固含量、冻干溶剂组成及聚酰亚胺链结构,成功实现了对PI气凝胶微观形态的调控。研究发现,以纯水作为... 详细信息

将一定浓度的水溶性聚酰胺酸盐(PAAS)溶液先通过冷冻干燥制备PAAS气凝胶,再经热酰亚胺化得到聚丙烯酰胺(PI)气凝胶。通过调控PAAS溶液固含量、冻干溶剂组成及聚酰亚胺链结构,成功实现了对PI气凝胶微观形态的调控。研究发现,以纯水作为冻干溶剂,得到孔径为110μm左右的蜂窝状结构,随着固含量的增加,孔壁厚度增加。以叔丁醇替代部分水作为冻干剂,随着叔丁醇含量增加,孔洞尺寸先减小后增加,在水和叔丁醇共晶点(20%)附近孔洞尺寸最小。当叔丁醇质量分数为50%时,所得PI链结构刚性不同,其微观形态也不同。进一步研究链柔顺性和微观形态对气凝胶压缩性能的影响发现,气凝胶微观形态对其抗压能力起主要作用。

关键词：聚酰亚胺气凝胶形态调控冷冻干燥压缩性能