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Ready,set,go:Medical preparations for the Paris 2024 Paralympic Games
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作者 Carolette Snyders Wayne Derman Martin Schwellnus 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期726-727,共2页
1.Introduction In August 2024,over 4400 Paralympic athletes will gather in Paris for the Paralympic Summer Games—the pinnacle of every Paralympian’s(Para athletes competing at the Paralympic Games)career to showcase... 1.Introduction In August 2024,over 4400 Paralympic athletes will gather in Paris for the Paralympic Summer Games—the pinnacle of every Paralympian’s(Para athletes competing at the Paralympic Games)career to showcase their ability and skills.Their training,preparation,and effort in the years leading up to the Games are unparalleled.To achieve success,Paralympians specifically rely on a medical support team to achieve their goals.So,what is required of the medical support team to prepare Paralympians to get ready,set,and go to Paris 2024? 展开更多
关键词 paris GAMES ATHLETES
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China Cultural Center in Paris Holds Tai Chi Workshop
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《China & The World Cultural Exchange》 2024年第6期11-11,共1页
To celebrated the World Tai Chi Day in 2024,China Cultural Center in Paris specially held a 24 Form Tai Chi workshop in the"Chinese Story"series of lectures on April 27,2024.Senior Tai Chi teacher and martia... To celebrated the World Tai Chi Day in 2024,China Cultural Center in Paris specially held a 24 Form Tai Chi workshop in the"Chinese Story"series of lectures on April 27,2024.Senior Tai Chi teacher and martial arts coach Zhang Jianyong and martial arts teacher John Huynh jointly taught the theoretical essence and essential movements,the 24 Form Tai Chi.18 Tai Chi enthusiasts from both France and Switzerland travelled to attend in the class and experience the legendary charm of this Chinese cultural treasure,injecting vitality to World Tai Chi Day celebration. 展开更多
关键词 TRAVEL jointly paris
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Early Quality Life Impairment in Alzheimer Disease’s Patients in Geriatric Department: About 214 Cases in Pitié Salpêtrière Hospital of Paris (France)
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作者 Andia Abdoulkader Audrey Rouet +4 位作者 Benedicte Dieudonné Jacque Boaddert Charlotte Tomeo Sandrine Greffard Marc Verny 《Open Journal of Internal Medicine》 2024年第1期30-42,共13页
Alzheimer’s disease (AD) is the most common neurodegenerative disease causing an alteration of life quality in the terminal stage. The purpose was to report 14 years of experience about the early impact on the qualit... Alzheimer’s disease (AD) is the most common neurodegenerative disease causing an alteration of life quality in the terminal stage. The purpose was to report 14 years of experience about the early impact on the quality of life of patients with AD. Methodology: Descriptive retrospective study over 14 years in the geriatric department of Pitié Salpêtrière Hospital, using the activity of daily living, Instrumental activity of daily living, neuropsychological inventory and Hoen Yahr scale evaluated at the time of diagnosis of AD according to the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer Disease’s and Related Disorders Association diagnostic criteria. Results: A total of 214 exploitable files had been listed. At the moment of diagnosis, the mean age was 82.1 years with extremes 68 to 95 with sex ratio 1.6 in women’s favor. The mean socio-cultural level was 4.9 with extremes about 0 to 7. There was poly pathology with a mean Cumulative Illness Rate Scale = 4.6 with extremes 0 to 16. the mean cognitive status was moderate = 22.5 with extremes 0 to 30. Quality life showed moderate impairment of IADL = 9.2 with extreme 3 to 11 compared to activity of daily living. The activity of daily living was more affected in 68 - 80-year-olds, while poly pathology impacted more on IADL in men. The cognitive impairment was more deficient in IADL when the MMSE test was low. The common disorders at the NPI were psychological, behavioral and psychotic. Conclusion: At the early diagnosis of Alzheimer’s Disease cognitive deficiencies were predominant and influenced on global Instrumental activity and psychological, behavioral disorders. 展开更多
关键词 Alzheimer’s Disease IADL ADL NPI paris FRANCE
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Hierarchical Media Ethics in the Digital Age: An Analysis of the “Primary School Student Lost Homework in Paris” Incident
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作者 ZHAO Yifei 《Journalism and Mass Communication》 2024年第3期205-208,共4页
In the digital age,traditional media ethics norms lack sufficient explanatory power and binding force in practice.This paper uses the“Primary School Student Lost Homework in Paris”incident as a case study to explore... In the digital age,traditional media ethics norms lack sufficient explanatory power and binding force in practice.This paper uses the“Primary School Student Lost Homework in Paris”incident as a case study to explore the ethical controversies surrounding the dissemination of this event.By adopting a hierarchical media ethics perspective,the paper dynamically examines the ethical conduct of various communicators,elucidates the ethical responsibilities of each party involved,and reveals the complexity of communication ethics in the digital age. 展开更多
关键词 media ethics information dissemination self-media ethics norms “Primary School Student Lost Homework in paris
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PARIS原则:开放协作环境下科学数据的可用性 被引量:2
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作者 沈志宏 张晓林 郑晓欢 《大数据》 2023年第4期172-188,共17页
科学数据利用的需求日益迫切,且在“第四范式”“融合科学”等新型科研范式带来的开放协作环境下,呈现出跨边界、端到端、动态性和协作化的特征。作为“数据仓储时代”的产物,FAIR、TRUST原则已无法为开放协作环境下科学数据的高效利用... 科学数据利用的需求日益迫切,且在“第四范式”“融合科学”等新型科研范式带来的开放协作环境下,呈现出跨边界、端到端、动态性和协作化的特征。作为“数据仓储时代”的产物,FAIR、TRUST原则已无法为开放协作环境下科学数据的高效利用提供深入的指导。详细分析了科学数据利用的典型场景,提出开放协作环境下促进科学数据利用的PARIS原则:可处理(processable)、可问答(askable)、可信赖(reliable)、可联合(incorporable)与可供给(suppliable),并重点分析了PARIS原则对科学数据可用性的促进作用。最后,探讨了实现PARIS原则可参考的技术路径。作为FAIR、TRUST原则的有益扩展,期望PARIS原则能有效提升科学数据的可用性。 展开更多
关键词 FAIR原则 TRUST原则 paris原则 数据利用 数据可用性
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Temporal transcriptomics reveal the molecular mechanism of dormancy and germination regulated by temperature in Paris polyphylla seed 被引量:2
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作者 Dengqun Liao Yalan Chen +4 位作者 Jianjun Qi Hongliang Zhang Peng Sun Caixia Chen Xian'en Li 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第4期848-866,共19页
The mature seed of Paris polyphylla var.chinensis(PPC)is morphophysiologically dormant and develops differently under warm and cold temperatures.To elucidate the molecular mechanisms underlying temperature-dependent r... The mature seed of Paris polyphylla var.chinensis(PPC)is morphophysiologically dormant and develops differently under warm and cold temperatures.To elucidate the molecular mechanisms underlying temperature-dependent regulation of PPC seed dormancy and germination,we investigated the dynamic changes in PPC seed transcript levels under warm and cold temperature stratifications(WS and CS,respectively)by time-resolved RNA sequencing,focusing on genes related to hormone metabolism and signaling and cell wall remodeling(CWRM)and encoding transcription factors/regulators(TFs/TRs).A total of 48765 and 47836 differentially expressed genes(DEGs)were associated with WS and CS,respectively.Of these,17581 and 16652 DEGs,respectively,unique to WS and CS,and 5386 were common to both temperature stratifications across nine analyzed growth stages.The expression of hormone metabolism and signaling,TF/TR,and CWRM genes were closely associated with temperature.More genes related to gibberellin(GA),cytokinin,auxin,and brassinosteroid biosynthetic were upregulated in WS as compared to CS seeds,while genes related to dormancy release and germination were downregulated in WS seeds.However,only GA and abscisic acid levels were altered in PPC seeds breaking morphophysiological dormancy(MPD).Overall,37 TF and five TR families were upregulated whereas 24 TF and 16 TR families were downregulated in WS as compared to CS seeds.Most CWRM families were highly expressed under WS as compared to CS,suggesting that they promote endosperm weakening and embryo growth of WS seeds and facilitate MPD release and germination.A coexpression analysis revealed positive correlations between TFs/TRs and DEGs involved in hormone metabolism and signaling and CWRM.These results provided a basis for investigating the interaction between the endosperm and underdeveloped embryo in the regulation of PPC seed germination and seedling emergence. 展开更多
关键词 paris polyphylla var.chinensis Morphophysiologically dormant seed Temperature stratification Time transcriptome PHYTOHORMONE Transcription factor Cell wall remodeling gene
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基于修正Paris法则的沥青混合料抗疲劳开裂性能分析 被引量:1
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作者 马子嵘 《福建交通科技》 2023年第4期1-4,共4页
疲劳开裂是沥青路面常见的病害,它的出现会显著降低路面承载力并加速水损害、车辙等其他病害产生,影响路面服役耐久性与行车安全性,因此准确评价沥青混合料的抗疲劳开裂性能至关重要。研究以损伤密度作为表征变量,通过能量平衡方程及修... 疲劳开裂是沥青路面常见的病害,它的出现会显著降低路面承载力并加速水损害、车辙等其他病害产生,影响路面服役耐久性与行车安全性,因此准确评价沥青混合料的抗疲劳开裂性能至关重要。研究以损伤密度作为表征变量,通过能量平衡方程及修正Paris法则建立可准确描述沥青混合料内部众多裂缝无规则发展的抗疲劳方程,并提出采用Paris模型参数n′进行沥青混合料抗疲劳开裂性能评价;进而选取4种类型沥青混合料,进行2种应变水平下的重复拉伸力学试验,计算获取各沥青混合料损伤状态下的动态模量与相位角以及破损密度曲线,最终通过修正Paris模型拟合获取抗开裂性能评价指标,并以此量化4种沥青混合料的抗疲劳开裂性能。 展开更多
关键词 疲劳开裂 沥青混合料 损伤密度 修正paris法则 能量平衡方程
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Comparison of polysaccharides from 10 species of genera Paris,Trillium,Aspidistra,and Polygonatum
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作者 Cheng-Cheng Zhao Ping Zhao +4 位作者 Ying Wang Ying Wang Xiao-Xiao Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2023年第5期21-30,共10页
Background:The genera Paris,Trillium,Aspidistra,and Polygonatum originally belonged to the family Liliaceae;however,recently,in the APG system,the genera Polygonatum and Aspidistra were placed in the family Asparagace... Background:The genera Paris,Trillium,Aspidistra,and Polygonatum originally belonged to the family Liliaceae;however,recently,in the APG system,the genera Polygonatum and Aspidistra were placed in the family Asparagaceae and the genera Paris and Trillium were placed in the family Melanthiaceae.Methods:To study the application of polysaccharide chemotaxonomy in Asparagaceae and Melanthiaceae,we extracted polysaccharides from the rhizomes of plants,including Paris polyphylla var.yunnanensis,Paris daliensis,Paris polyphylla var.chinensis,Trillium tschonoskii,Aspidistra elatior,Aspidistra sichuanensis,Aspidistra caespitosa,Polygonatum sibiricum,Polygonatum cyrtonema,and Polygonatum kingianum.Physicochemical and structural characterization of these polysaccharides was performed using molecular weight,monosaccharide composition,Fourier-transform infrared spectroscopy,nuclear magnetic resonance spectroscopy,and scanning electron microscopy.The immunomodulatory activities were evaluated using the macrophage cell line,RAW264.7.Results:In this study,we found that the polysaccharides from the genus Polygonatum and Aspidistra were mainly comprised of fructose and glucose;the molecular weights were mostly concentrated between 4.6-6.2 kDa.The polysaccharides from species of genus Polygonatum differed in that they contained acetyl groups,while polysaccharides from species of genus Aspidistra did not.Paris and Trillium species polysaccharides mainly consisted of glucose and mannose;the molecular weights of the two major peaks were 6.3-13 kDa and 1-1.5 kDa,respectively;the main differences between polysaccharides were the ratio of glucose and mannose and the degree of branching.These results suggest that fructans might be the main feature of the family Asparagaceae and fructans with acetyl groups might be the main feature of the genus Polygonatum which is consistent with the results of previous studies.Additionally,all polysaccharides from the 10 plants promoted phagocytic activity.Some of them exhibited strong activity,including nitrogen monoxide release and TNF-αsecretion by RAW264.7 macrophages,indicating that they could be used as potential immunomodulatory agents.Conclusion:The molecular weight distribution,monosaccharide composition,and surface morphology of the polysaccharides of the Polygonatum and Aspidistra plants were similar,while those of Paris and Trillium plants were similar.These results support the APG classification system,which placed the genera Polygonatum and Aspidistra in the Asparagaceae family and placed the genera Paris and Trillium in the Melanthiaceae family. 展开更多
关键词 paris Trillium Aspidistra POLYGONATUM POLYSACCHARIDES
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Texworld Paris celebrates 25 years!
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《China Textile》 2023年第2期46-47,共2页
Texworld Paris celebrates 25 years!The anniversary edition of Texworld Evolution Paris will take place this summer from 3 to 5 July 2023 at the Porte de Versailles Exhibi­tion Centre.For the first time,this event... Texworld Paris celebrates 25 years!The anniversary edition of Texworld Evolution Paris will take place this summer from 3 to 5 July 2023 at the Porte de Versailles Exhibi­tion Centre.For the first time,this event will be held downtown Paris.1,300 exhibitors from some twenty countries have already confirmed their presence. 展开更多
关键词 paris FIR celebrate
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基于临界曲面的改进Paris定律球轴承疲劳寿命预测方法 被引量:14
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作者 徐东 徐永成 +2 位作者 陈循 李兴林 杨拥民 《机械工程学报》 EI CAS CSCD 北大核心 2011年第2期51-57,共7页
通过场发射扫描电镜对球轴承疲劳故障点微观结构进行观察,发现裂纹总是沿着某个曲面进行萌生和扩展,扩展到一定程度后发生断裂形成近似椭圆形状的剥落点,随着球轴承的运转,不仅断裂后的裂纹发生二次剥落,而且剥落点将在新的曲面上发生... 通过场发射扫描电镜对球轴承疲劳故障点微观结构进行观察,发现裂纹总是沿着某个曲面进行萌生和扩展,扩展到一定程度后发生断裂形成近似椭圆形状的剥落点,随着球轴承的运转,不仅断裂后的裂纹发生二次剥落,而且剥落点将在新的曲面上发生多次剥落,形成断层形貌。基于此种现象,提出球轴承临界曲面的概念,假定裂纹的萌生和扩展均在此临界曲面上,将三维裂纹扩展问题转化为二维裂纹扩展问题进行分析。在临界曲面概念的基础上,提出改进的Paris疲劳寿命预测模型,将疲劳寿命分为裂纹扩展和剥落点增大两部分,分段采用改进的Paris定律预测球轴承的疲劳寿命。通过多套SKF 6205深沟球轴承疲劳寿命试验数据进行验证,与传统的SKF L-P公式预测结果相比,提出的方法能够较好地预测球轴承的疲劳寿命。 展开更多
关键词 临界曲面 paris 定律 疲劳寿命预测 预测模型 球轴承
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钛合金疲劳裂纹扩展速率Paris区中的转折点 被引量:16
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作者 马英杰 刘建荣 +3 位作者 雷家峰 李玉兰 刘羽寅 杨锐 《金属学报》 SCIE EI CAS CSCD 北大核心 2008年第8期973-978,共6页
通过对比钛合金不同显微组织下疲劳裂纹扩展速率Paris区转折点的位置,发现原始β晶粒尺寸是影响Paris区转折点位置的主要因素,晶团尺寸以及片层厚度对转折点位置没有影响.并且通过分析转折点前、后疲劳裂纹扩展微观阶段的转变及断裂方... 通过对比钛合金不同显微组织下疲劳裂纹扩展速率Paris区转折点的位置,发现原始β晶粒尺寸是影响Paris区转折点位置的主要因素,晶团尺寸以及片层厚度对转折点位置没有影响.并且通过分析转折点前、后疲劳裂纹扩展微观阶段的转变及断裂方式变化,得出转折点的出现是疲劳裂纹尖端塑性区尺寸超过晶粒尺寸所致,具有β晶粒的马氏体组织疲劳裂纹扩展速率Paris区并不存在转折点,说明转折点的出现不仅仅是由于原始β晶粒的存在,还和显微组织类型有关.通过分析还发现,钛合金片层组织中裂纹尖端塑性区实际尺寸大于计算得到的单向塑性区尺寸以及循环塑性区尺寸. 展开更多
关键词 钛合金 疲劳裂纹扩展 paris区转折点 裂纹尖端塑性区尺寸
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基于SCB和3D-DIC技术的既有沥青路面剩余寿命预估
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作者 胡洪龙 江臣 +2 位作者 杨洋 程龙 张定一 《公路交通科技》 CAS CSCD 北大核心 2024年第2期48-56,78,共10页
在改扩建项目中准确评价超服役周期高速公路沥青路面的剩余寿命,对于合理制订既有高速公路沥青路面的利用策略至关重要。从服役周期超过20 a的高速公路上钻取27个沥青混凝土芯样,并制作成54个半圆试件,分别进行半圆弯曲(SCB)断裂和半圆... 在改扩建项目中准确评价超服役周期高速公路沥青路面的剩余寿命,对于合理制订既有高速公路沥青路面的利用策略至关重要。从服役周期超过20 a的高速公路上钻取27个沥青混凝土芯样,并制作成54个半圆试件,分别进行半圆弯曲(SCB)断裂和半圆弯曲(SCB)疲劳试验,评价既有沥青混凝土路面的抗疲劳特性和剩余寿命。为解决传统测试方法无法实时捕捉沥青混凝土在高周疲劳试验中试件表面裂缝拓展问题,引入立体数字图像关联(3DDIC)技术监测试件表面应变场以及裂缝长度随疲劳荷载次数的演化趋势,结合K-d tree算法计算了每个疲劳荷载循环对应DIC图像中裂缝长度的变化。同时,采用双线性软化内聚区模型(CZM)确定沥青混凝土裂缝的应变阈值,从而保证了K-d tree算法计算裂缝长度的准确性。构建了Paris方程主曲线消除沥青混凝土开裂参数在不同应力比下的不一致性,在宽荷载域范围内表征各种路段沥青混凝土的抗疲劳性能。结果表明:既有沥青混凝土裂缝的应变阈值为1980με;随着应力比的增大,Paris方程A和n参数分别表现出波动增加和平稳下降趋势,而应力强度因子阈值呈平稳上升趋势;K84,K124,K165路段沥青面层剩余寿命分别为2.13E+08,3.57E+08,1.02E+07,除K165路段外,其他路段的剩余疲劳寿命均满足路面设计年限内交通量要求。 展开更多
关键词 道路工程 剩余疲劳寿命 SCB试验 既有沥青路面 CZM paris方程
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TA17钛合金板状连接件的疲劳裂纹扩展行为研究
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作者 匡格平 王群 +2 位作者 黄学伟 刘彬 徐文涛 《宇航材料工艺》 CAS CSCD 北大核心 2024年第2期75-81,共7页
TA17钛合金是航空航天等工程中重要的结构材料,其疲劳裂纹扩展性能直接影响整体结构的安全性和完整性。本文基于Cr2Ni2MoV钢材紧凑拉伸试样斜裂纹疲劳裂纹扩展的试验结果,验证了ABAQUS软件XFEM模块用于分析平面应力状态下疲劳裂纹扩展... TA17钛合金是航空航天等工程中重要的结构材料,其疲劳裂纹扩展性能直接影响整体结构的安全性和完整性。本文基于Cr2Ni2MoV钢材紧凑拉伸试样斜裂纹疲劳裂纹扩展的试验结果,验证了ABAQUS软件XFEM模块用于分析平面应力状态下疲劳裂纹扩展的有效性,然后采用XFEM模块分析了TA17钛合金及其连接件的疲劳裂纹扩展性能。结果表明降低最大荷载、减小加载比和采用长圆孔型均可有效提高TA17钛合金连接件的疲劳寿命。采用XFEM模块可以预测连接件疲劳寿命的S-N曲线,预测TA17钛合金结构载荷增大33.3%,疲劳寿命减小为原来的1/4,可为工程疲劳设计提供参考依据。 展开更多
关键词 钛合金 疲劳裂纹扩展 断裂力学 XFEM paris公式
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疲劳裂纹扩展规律Paris公式的一般修正及应用 被引量:40
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作者 倪向贵 李新亮 王秀喜 《压力容器》 北大核心 2006年第12期8-15,19,共9页
介绍了疲劳裂纹扩展规律Paris公式及其与传统应力疲劳S-N曲线的关系,分析了计算疲劳裂纹扩展寿命的一般过程。阐述了当前Paris公式在工程中的一般修正,具体描述了不同的修正形式及其主要特征,简要介绍了Paris公式在弹塑性断裂力学和连... 介绍了疲劳裂纹扩展规律Paris公式及其与传统应力疲劳S-N曲线的关系,分析了计算疲劳裂纹扩展寿命的一般过程。阐述了当前Paris公式在工程中的一般修正,具体描述了不同的修正形式及其主要特征,简要介绍了Paris公式在弹塑性断裂力学和连续损伤力学中的修正及应用。各种应用实践表明,对于不同要求的工程问题要采用相应的修正形式。 展开更多
关键词 疲劳裂纹 扩展速率 paris公式
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广义Paris公式预测沥青路面的疲劳寿命 被引量:9
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作者 曾梦澜 马正军 易昕 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第6期20-23,共4页
重复作用的交通荷载可以在路面沥青混合料细微缺陷或裂缝的尖端造成应力集中并以复杂的形式自上而下扩展,最终导致路面的疲劳开裂破坏.本文应用断裂力学的原理探讨沥青路面疲劳寿命的预测方法.计算与分析表明:广义Paris公式可以考虑沥... 重复作用的交通荷载可以在路面沥青混合料细微缺陷或裂缝的尖端造成应力集中并以复杂的形式自上而下扩展,最终导致路面的疲劳开裂破坏.本文应用断裂力学的原理探讨沥青路面疲劳寿命的预测方法.计算与分析表明:广义Paris公式可以考虑沥青路面结构内材料复杂的裂缝扩展;沥青面层的疲劳寿命随着面层厚度的增加以近似线性的幂函数的形式增加;另一方面,沥青面层的疲劳寿命随着面层材料模量的降低以负指数的幂函数的形式增加. 展开更多
关键词 道路工程 沥青路面 疲劳寿命 断裂力学 paris公式
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Q235材料的Paris常数C、m及ΔK_(th)值测试 被引量:14
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作者 董达善 梅潇 《机械强度》 CAS CSCD 北大核心 2003年第2期215-218,共4页
以大型机械结构最常用的Q2 3 5板材 (等同于ASTMA3 6)为研究对象 ,在实验室条件下测取裂纹扩展速率的Paris常数C、m ,并验证与轧制方向垂直的裂纹受平行于轧制方向应力作用时最易扩展的结论。同时以应力比R =0 .1加载试验数据外延计算... 以大型机械结构最常用的Q2 3 5板材 (等同于ASTMA3 6)为研究对象 ,在实验室条件下测取裂纹扩展速率的Paris常数C、m ,并验证与轧制方向垂直的裂纹受平行于轧制方向应力作用时最易扩展的结论。同时以应力比R =0 .1加载试验数据外延计算获得其门槛值ΔKth(da dN =0 .5× 10 - 6 mm cycle时 )。 展开更多
关键词 裂纹 疲劳裂纹扩展 门槛值 paris常数 断裂 Q235钢
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Primary Comments on Chemotaxonomy of Paris spp. Based on Saponins Analysis 被引量:6
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作者 黄芸 王强 崔力剑 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第3期176-180,共5页
Aim The several species of the genus Paris called "Chonglou" are famous traditional Chinese herbal medicines. We established the quantitative analysis method of the steroidal saponins in some species of the genus Pa... Aim The several species of the genus Paris called "Chonglou" are famous traditional Chinese herbal medicines. We established the quantitative analysis method of the steroidal saponins in some species of the genus Paris and discussed their relations. Methods We detected the contents of 11 steroidal saponins in Paris samples with a Kromasel C18 ( 150 mm× 4.6 mm ID, 5μm) column which was subjected to gradient elution with acetonitrile-water (30:70- 60:40, V/V) at a flow rate of 1 mL· min^-1 by HPLC-ELSD and established chemical cluster tree using SPSS 11 software. Results All the samples could be separated and calibration curves of 11 saponins were prepared. We successfully detected the contents of 11 steroidal saponins in 14 Paris spp. in 30 min. The recovery for the assay of saponins was between 95 % and 97 %. The RSD of precision of 11 saponins and stability of samples were below 3 %. Chemical phylogenetic tree based on saponin contents indicated that 17 samples of Paris spp. clustered separately. Conclusion The established method is accurate and convenient, and suitable for the quantitative analysis of these 11 steroidal saponins in Paris spp.. The chemical phylogenetic tree is in accordance with Takhtajian classical taxonomy. 展开更多
关键词 paris steroidal saponin cluster analysis HPLC-ELSD
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PARIS出血评分对急性心肌梗死药物支架术后患者院内出血的预测价值--中国急性心肌梗死注册研究 被引量:4
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作者 赵雪燕 杨进刚 +14 位作者 范肖雪 张峻 吴元 王杨 许海燕 高晓津 窦克非 唐熠达 乔树宾 苏淑红 杨红梅 张旭霞 袁晋青 李卫 杨跃进 《中国循环杂志》 CSCD 北大核心 2018年第2期110-116,共7页
目的:评估支架术后抗血小板药物停药模式(PARIS)出血评分对我国使用药物洗脱支架(DES)并应用双联抗血小板治疗(DAPT)的急性心肌梗死(AMI)患者住院期间出血的预测价值。方法:中国急性心肌梗死(CAMI)注册研究在2013-01-01至2014-09-30期间... 目的:评估支架术后抗血小板药物停药模式(PARIS)出血评分对我国使用药物洗脱支架(DES)并应用双联抗血小板治疗(DAPT)的急性心肌梗死(AMI)患者住院期间出血的预测价值。方法:中国急性心肌梗死(CAMI)注册研究在2013-01-01至2014-09-30期间107家医院连续入选了27 594例AMI患者,其中14 625例在住院期间成功置入DES并接受DAPT,分别采用出血学术研究联合会(BARC)3型和5型及BARC 2型、3型和5型做为出血的终点事件,评价我国置入DES术后接受DAPT的AMI患者住院期间出血发生情况、临床特征和PARIS出血评分对这两种出血终点事件的预测价值。结果:出血患者的PARIS评分明显高于无出血患者(P<0.001)。按照PARIS评分的危险分层,以BARC 3型和5型为出血终点时,共有77例(0.53%)患者出现出血事件,高危、中危、低危患者之间的PARIS评分差异有统计学意义(P<0.001)。出血中危患者出血风险是低危患者的2.38倍(P=0.006);出血高危患者出血风险是低危患者的4.78倍(P<0.001)。以BARC 2型、3型和5型为出血终点,共有223例(1.52%)出现出血事件。出血中危患者出血风险是低危患者的1.64倍(P=0.002);出血高危患者出血风险是低危患者的2.23倍(P=0.001)。受试者工作特征(ROC)曲线分析显示,PARIS出血评分对以BARC 3型和5型或BARC 2型、3型和5型为出血事件终点均有预测价值。对以BARC 3型和5型为终点的预测价值[曲线下面积(AUC):0.672]高于以BARC 2型、3型和5型为出血事件终点的预测价值(AUC:0.596;z=2.079,P=0.038),即PARIS出血评分对严重出血的预测价值更优。结论:PARIS出血评分对置入DES并接受DAPT的AMI患者住院期间出血具有预测价值,并可用于危险分层。PARIS出血评分对严重出血作为终点事件的预测价值更优。 展开更多
关键词 paris出血评分 心肌梗死 药物支架
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Different Understory Cultivation Techniques of Paris polyphylla Smith 被引量:4
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作者 龚舟 龚范武 +1 位作者 彭静 罗先权 《Agricultural Science & Technology》 CAS 2016年第2期353-357,共5页
This study was conducted for the purposes of reducing consumption of wild resources of Paris polyphylla Smith, satisfying the market demand, saving the production cost, improving utilization rate of forest land, incre... This study was conducted for the purposes of reducing consumption of wild resources of Paris polyphylla Smith, satisfying the market demand, saving the production cost, improving utilization rate of forest land, increasing income of foresters and protecting ecological environment. Three types of fores{ land, i.e., the evergreen forest land (China fir forest), deciduous forest land (walnut forest) and shrub land (honey suckle forest.) were selected, and seeds and cut rhizomes of Paris polyphylla Smith produced in Bamian Mountain, Hunan, were used in the study on understory seedling raising and cultivation techniques. The results showed that: when using different propagation materials, seed propagation could be adopted to reduce the consumption of wild resources and provide a large number of seedlings, and was beneficial to large-scale planting; and when conducing seedling and plantlet raising followed by transplanting and direct seeding and planting using different propagation materials in large-scale understory cultivation, direct seeding/ planting was appropriate for saving save production cost with the advantage of early production. Among the 3 different types of forest land, the best choice was broad- leaved forest land, which could achieve better economic benefit because of con- forming with the ecological habit and growth and development law of Paris poly- phylla Smith. 展开更多
关键词 paris polyphylla Smith PROPAGATION Seedling raising Direct seeding Understory cultivation
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杂质磷对单晶硅微结构疲劳特性的影响——基于Paris公式的分析 被引量:2
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作者 刘彬 陶俊勇 +2 位作者 张云安 陈循 王晓晶 《机械工程学报》 EI CAS CSCD 北大核心 2014年第24期86-92,共7页
硅基微机电系统中的单晶硅微结构常工作于循环加载状态,易发生疲劳失效。单晶硅微结构疲劳寿命的分散度较大,难以根据不同掺磷浓度试样的疲劳寿命测试数据对比分析出杂质磷对单晶硅微梁弯曲疲劳特性的影响规律,针对此问题进行研究。设... 硅基微机电系统中的单晶硅微结构常工作于循环加载状态,易发生疲劳失效。单晶硅微结构疲劳寿命的分散度较大,难以根据不同掺磷浓度试样的疲劳寿命测试数据对比分析出杂质磷对单晶硅微梁弯曲疲劳特性的影响规律,针对此问题进行研究。设计一种弯曲测试结构,该结构可同时对四根微梁进行疲劳测试;设计一种简易的弯曲测试装置,该装置在满足测试精度的同时有效地控制了成本。用各向异性湿法工艺制备6组不同掺磷浓度的试样,并在常温空气环境中对试样进行弯曲疲劳测试。基于Paris公式建立一种微结构疲劳寿命预测的概率模型,用模型对测试数据进行拟合计算,得到材料常数C和n。C随掺磷浓度降低近3个量级,而n增量较小,表明C的变化占主导。所以疲劳裂纹扩展速率有随掺磷浓度增高而降低,这可为硅基微机电系统的疲劳可靠性设计提供有价值的参考。 展开更多
关键词 微机电系统 单晶硅微梁 弯曲疲劳寿命 掺磷 paris公式
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