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Research on the Fatigue Flexural Performance of RC Beams Attacked by Salt Spray

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China Ocean Engineering 2018年第2期32卷 179-188页

作者： MAO Jiang-hong XU Fang-yuan JIN Wei-liang ZHANG Jun WU Xi-xi chen cai-sheng Ningbo Institute of Technology Zhejiang UniversityNingbo 315100China Zhejiang Institute of Communications Hangzhou 311112China Institute of Structural Engineering Zhejiang UniversityHangzhou 310058China

The fatigue flexural performance of RC beams attacked by salt spray was studied. A testing method involving electro osmosis, electrical accelerated corrosion and salt spray was proposed. This corrosion process method effectively simulates real-world salt spray and fatigue loading exerted by RC components on sea bridges. Four RC beams that have different stress amplitudes were tested. It is found that deterioration by corrosion and fatigue loading reduces the fatigue life of the RC and decreases the ability of deformation. The fatigue life and deflection ability could be reduced by increasing the stress amplitude and the corrosion duration time. The test result demonstrates that this experimental method can couple corrosion deterioration and fatigue loading reasonably. This procedure may be applied to evaluate the fatigue life and concrete durability of RC components located in a natural salt spray environment.

关键词： reinforced concrete fatigue loading concrete durability coupling interaction evaluation

Genotypic Differences in Growth and Physiological Responses to Transplanting and Direct Seeding Cultivation in Rice

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Rice science 2009年第2期16卷 143-150页

作者： chen Song cai sheng-guan chen Xin ZHANG Guo-ping Agronomy Department Huajiachi Campus Zhejiang University Hangzhou 310029 China

The field experiments were conducted to investigate the growth and physiological responses of six super hybrid rice combinations to two planting methods, transplanting （TP） and direct seeding （DS） during 2006-2007 and 2007-2008. The 1000-grain weight and number of tillers per plant at the early growth stage, the maximum quantum yield of PSII （Fv/Fm） and transpiration rate （Tr） were higher in DS plants than in TP ones, whereas the grain yield, number of panicles per square meter, seed setting rate, net photosynthetic rate （Po） and stomatal conductance were lower in DS plants. However, little difference was detected in number of grains per panicle, stem （shoot） and leaf weight between the combinations in the two planting methods. The responses of plant growth and physiological traits to planting method differed greatly among the six combinations. In both planting methods, Chouyou 58 and Yongyou 6 had the highest and lowest panicle biomass and Pn, respectively. The higher yield of Chunyou 58 was associated with more numbers of panicles per square meter and grains per panicle in both planting methods. The results indicate that lower grain yield in DS relative to TP is attributed to more excessive tillers at the early stage, lower leaf biomass and photosynthetic rate at the late stage.

关键词： rice Oryza sativa direct seeding transplanting genotypic difference photosynthesis biomass

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密尔防范“社会暴虐”思想探微

河南大学学报（社会科学版） 2008年第2期48卷 148-152页

作者：陈胜才天津师范大学政治文化研究中心

密尔站在时代的高度,认为大众化民主内在的弊端可能会给个人自由带来严重的危害。为维护个人自由,人们不仅要防御政府专制,而且更要抗拒"社会暴虐"。他提出了对个人自由与社会控制进行划界的两条原则,这种群己权界的观点也是防范"社会暴... 详细信息

密尔站在时代的高度,认为大众化民主内在的弊端可能会给个人自由带来严重的危害。为维护个人自由,人们不仅要防御政府专制,而且更要抗拒"社会暴虐"。他提出了对个人自由与社会控制进行划界的两条原则,这种群己权界的观点也是防范"社会暴虐"的基本原则;包括思想自由、个性自由等在内的社会自由是防范"社会暴虐"的根本出路。

关键词：密尔社会暴虐群己权界社会自由

含有非局部项抛物型方程整体解的不存在性(英文)

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南京大学学报（自然科学版） 2007年第4期43卷 411-418页

作者：陈才生王辉河海大学数学系南京210098

本文研究一类含有非线性局部顶的抛物型m-Laplacian方程的柯西初值问题ut=div(|u|m-2u)+∫RNK(x,y)up(y,t)dyx∈RN,t>0u(x,0)=u0(x),x∈RN,u(x,t)≥0(x,t)∈RN×R+(0.1)的非负整体解的不存在性问题.从两个角度出发,研究参数p,β,m和初始条件u0(x)在无穷远处的渐近行为对问题(0.1)解的不存在性的影响.采用的方法是"试验函数法".该方法是由Mitidieri和Pohozaev在研究一类椭圆型不等式时首先提出.为了使该方法能够用于问题(0.1),需要作些修正.主要结果的证明是通过对解的先验估计,然后应用反证法提出.通过选择适当的试验函数以及变量伸缩,得到解的一个渐近估计和一个上界估计.这些估计依赖于参数T和ρ.最后让ρ→∞和对上界极小化,得出问题(0.1)的非负解的不存在性.作如下假设:(H1)存在α0∈(0,1/2),使得当α∈(-α0,0),成立u0(x)≥0,u0∈Ll1oc+α(RN);(H2)存在K0>0,00,γ≥0使得K(x)≥K0(1+|x|2)-γ,x∈RN.主要结果是:定理1假设2≤mm-1和条件(H1),(H2)成立.进一步,如果下列条件之一满足:(H4)p0,使得liminf|x|→∞(u0(x)|x|m+βp+1-m-α)≥β0;那么初值问题(0.1)不存在整体的非负解.当K(x,y)只是一个变量y的函数时,有定理2假设2≤mm-1和条件(H1),(H3)成立.进一步,如果下列条件之一满足:(H6)0≤γ0,使得liminf|x|→∞(u0(x)|x|m+N-2γp+1-m-α)≥β2;那么问题ut=div(|u|m-2u)+∫RNK(y)up(y,t)dyx∈RN,t>0u(x,0)=u0(x),x∈RN不存在整体有界的非负解.

关键词：抛物型的m-拉普拉斯方程非局部顶整体解不存在性

Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

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Neural Regeneration Research 2025年第2期20卷 548-556页

作者： Zhihui Ren Tian Li Xueer Liu Zelin Zhang Xiaoxuan chen Weiqiang chen Kangsheng Li Jiangtao sheng Department of Microbiology and Immunology Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular ImmunopathologyShantou University Medical CollegeShantouGuangdong ProvinceChina Department of Neurosurgery First Affiliated Hospital of Shantou University Medical CollegeShantouGuangdong ProvinceChina

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system *** neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types ***-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related ***,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain *** this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from *** found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 *** VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical *** findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological ***,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

关键词： central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui chen Zuo-Tang Liang Yu-Gang Ma Xin-Li sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation