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Chinese Physics B 2012年第11期21卷 306-320页

作者：李凤臣蔡伟华张红娜王悦 School of Energy Science and Engineering Harbin Institute of Technology

Direct numerical simulations （DNS） were performed for the forced homogeneous isotropic turbulence （FHIT） with/without polymer additives in order to elaborate the characteristics of the turbulent energy cascading influenced by drag-reducing effects. The finite elastic non-linear extensibility-Peterlin model （FENE-P） was used as the conformation tensor equation for the viscoelastic polymer solution. Detailed analyses of DNS data were carried out in this paper for the turbulence scaling law and the topological dynamics of FHIT as well as the important turbulent parameters, including turbulent kinetic energy spectra, enstrophy and strain, velocity structure function, small-scale intermittency, etc. A natural and straightforward definition for the drag reduction rate was also proposed for the drag-reducing FHIT based on the decrease degree of the turbulent kinetic energy. It was found that the turbulent energy cascading in the FHIT was greatly modified by the drag-reducing polymer additives. The enstrophy and the strain fields in the FH1T of the polymer solution were remarkably weakened as compared with their Newtonian counterparts. The small-scale vortices and the small-scale intermittency were all inhibited by the viscoelastic effects in the FHIT of the polymer solution. However, the scaling law in a fashion of extended self-similarity for the FHIT of the polymer solution, within the presently simulated range of Weissenberg numbers, had no distinct differences compared with that of the Newtonian fluid case.

关键词： forced homogenous isotropic turbulence polymer additives turbulent energy cascading drag reduction

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梁板类构件焊接残余应力测试的试验方法研究

哈尔滨工程大学学报 2009年第5期30卷 501-507页

作者：田石柱李凤臣哈尔滨工业大学土木工程学院黑龙江哈尔滨150090 东华理工大学土工与环境工程学院江西抚州344000

针对焊接梁板类构件内部残余应力分布规律难以确定的问题,基于屈服及刚度衰减条件,提出了一种测定焊接残余应力分布的试验方法.该方法以对接焊钢板及焊接工字型梁为对象,进行了纵向焊接残余应力分布的试验测试研究,并将试验结果与有限... 详细信息

针对焊接梁板类构件内部残余应力分布规律难以确定的问题,基于屈服及刚度衰减条件,提出了一种测定焊接残余应力分布的试验方法.该方法以对接焊钢板及焊接工字型梁为对象,进行了纵向焊接残余应力分布的试验测试研究,并将试验结果与有限元数值模拟结果进行了对比分析,二者吻合较好.研究结果表明,该方法能够很好地确定板类及梁类焊接构件的纵向焊接残余应力分布规律,为钢结构设计提供一定的依据.同时该方法简单、精确,具有很强的工程实用和推广价值.

关键词：屈服及刚度衰减条件残余应力焊接梁板构件有限元分析

Expression of insulin-like growth factor 1 and insulin-like growth factor 1 receptor and its intervention by interleukin-10 in experimental hepatic fibrosis

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World Journal of Gastroenterology 2003年第6期9卷 1287-1291页

作者： Xiao-Zhong Wang Zhi-Xin chen li-Juan Zhang Yun-Xin chen Dan li feng-lin chen Yue-Hong Huang Department of Gastroenterology,Affiliated Union Hospital,Fujian Medical University,Fuzhou,350001,Fujian Province,China Department of Gastroenterology Affiliated Union Hospital Fujian Medical University Fuzhou 350001 Fujian Province China. drwangxz@***

AIM: To study the expression of IGF-1 and IGF-1R and its intervention by interleuldn-10 in the course of experimental hepatic ***: Hepatic fibrosis was induced in rats by carbon tetrachloride intoxication and liver specimens were taken from the rats administered CCl4 with or without IL-10 treatment and the animals of the control *** for insulin-like growth factor-1 (IGF-1)and IGF-1 receptor(IGF-1R) were demonstrated by immunohistochemistry, and their intensities were evaluated in different animal ***: The positive levels for IGF-1 and IGF-1R were increased with the development of hepatic fibrosis, with the positive signals localized in cytoplasm and/or at the plasmic membrane of hepatocytes. The positive signals of IGF-1 and IGF-1R were observed more frequently (Pliver tissue seems to be up-regulated during development of hepatic fibrosis induced by CC14, and exogenic IL-10 inhibits the responses.

关键词：肝纤维化胰岛素样生长因子-1 受体白细胞介素-10

Development of Multilayer Optics for the EUV, Soft X-ray and X-ray Regions in Tongji University

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光机电信息 2005年第12期22卷 12-21页

作者： WANG Zhan-shan ZHU Jing-tao WANG Hong-chang WANG feng-li chen ling-yan Institute of Precision Optical Engineering Department of Physics Tongji University Shanghai 200092 China

In EUV and X- ray regions, multilayer mirrors are the essential and necessary optics elements. The good prospects of the EUV and X- rays for next generation lithography system, microscopy in the “water windows”, astro- nomical telescope, spectroscopy, plasma diagnostics, and X- ray laser have impelled the development of multilayer optics. The paper introduces the recent results of the multilayer optics elements in Tongji University, including beam splitters, broadband/angular polarizers, supermirrors and high- reflectance mirrors. The product of reflectivity and transmissivity is above 4% for the Mo/Si multilayer beam splitter. Over the 15￣17 nm wavelength range, the s- re- flectivity of the non- periodic Mo/Si broadband multilayer polarizers is reasonably constant, as high as 36.6%, and the degree of polarization is more than 97.8%. At the fixed energy of 8 keV (Cu Kαline), the W/Si supermirror has the reflectivity of above 30% in the angle range of 0.4°￣0.85°, and a W/B4C supermirror has the reflectivity of about 20% in the angle range of 0.9°￣1.2°, and the reflectivity of W/C supermirror working in the grazing incident angle range of 0.9°￣1.2°is about 20%. The experimental results of some high- reflectance mirrors in our lab are also pre- sented, such as Mo/Si, Mo/Y, Cr/C, La/B4C, Si/C and Si/SiC. The reflectivity of Mo/Si multilayer is as high as 61.1% at wavelength of 13.4 nm.

关键词： EUV 软X射线同济大学多层膜应用光学电子束宽带偏振器

New Labdane Diterpenoids from Croton laui and Their Antiinflammatory Activities

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New Labdane Diterpenoids from Croton laui and Their Antiinfl...

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

中国化学会第十一届全国天然有机化学学术会议

作者： li Yang Yu-Bo Zhang li-feng chen Neng-Hua chen Zhong-Nan Wu Yao-Lan li Guo-Cai Wang Institute of Traditional Chinese Medicine ＆ Natural Products College of Pharmacy Jinan University

＜正＞Croton laui belongs to the genus Croton（Euphorbiaceae）,and is specially distributed in Hainan Province of *** plants of the genus Croton are used as folk medicines to treat stomachache,abscesses,malaria,and inflammation,ect.1 Previous phytochemical investigations have demonstrated that the plants of genus Croton are rich in diterpenoids,including clerodane,labdane,ent-kaurane,tigliane,and cembrane *** diterpenoids

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： feng Zhang chenyang Zhang linlin Wu Wei Sun Hongliang Zhang Jianhua chen Yong Pei Songjiang li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

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破损舰船剩余承载能力分析

大连海事大学学报 2008年第1期34卷 10-14页

作者：任慧龙李陈峰哈尔滨工程大学船舶工程学院哈尔滨150001

为对破损舰船剩余承载能力进行评估,采用Smith方法,给出了一种基于材料机械特性、板厚尺寸、破口尺寸等多种不确定性因素的破损舰船剩余承载能力的计算方法.对Reckling 23的仿真结果证明了该方法的准确性.实船条件下对不同破口位置和横... 详细信息

为对破损舰船剩余承载能力进行评估,采用Smith方法,给出了一种基于材料机械特性、板厚尺寸、破口尺寸等多种不确定性因素的破损舰船剩余承载能力的计算方法.对Reckling 23的仿真结果证明了该方法的准确性.实船条件下对不同破口位置和横倾角的剩余承载能力的计算表明:材料屈服限的变异性对破损舰船剩余承载能力的变异性影响最大,底部破损对其剩余承载能力的折减影响较大,横倾角的改变也将影响破损舰船的剩余承载能力.

关键词：破损舰船剩余承载能力 Smith法 Rosenbluthe法

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye li Shuang Pan Yihuang chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

Overexpression of low-density lipoprotein receptor prevents neurotoxic polarization of astrocytes via inhibiting NLRP3 inflammasome activation in experimental ischemic stroke

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Neural Regeneration Research 2025年第2期20卷 491-502页

作者： Shuai feng Juanji li Tingting liu Shiqi Huang Xiangliang chen Shen liu Junshan Zhou Hongdong Zhao Ye Hong Department of Neurology Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Jinling HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina

Neurotoxic astrocytes are a promising therapeutic target for the attenuation of cerebral ischemia/reperfusion ***-density lipoprotein receptor,a classic cholesterol regulatory receptor,has been found to inhibit NLR family pyrin domain containing protein 3(NLRP3)inflammasome activation in neurons following ischemic stroke and to suppress the activation of microglia and astrocytes in individuals with Alzheimer’s ***,little is known about the effects of low-density lipoprotein receptor on astrocytic activation in ischemic *** address this issue in the present study,we examined the mechanisms by which low-density lipoprotein receptor regulates astrocytic polarization in ischemic stroke ***,we examined low-density lipoprotein receptor expression in astrocytes via immunofluorescence staining and western blotting *** observed significant downregulation of low-density lipoprotein receptor following middle cerebral artery occlusion reperfusion and oxygen-glucose deprivation/***,we induced the astrocyte-specific overexpression of low-density lipoprotein receptor using astrocyte-specific adeno-associated ***-density lipoprotein receptor overexpression in astrocytes improved neurological outcomes in middle cerebral artery occlusion mice and reversed neurotoxic astrocytes to create a neuroprotective ***,we found that the overexpression of low-density lipoprotein receptor inhibited NLRP3 inflammasome activation in oxygen-glucose deprivation/reoxygenation injured astrocytes and that the addition of nigericin,an NLRP3 agonist,restored the neurotoxic astrocyte *** findings suggest that low-density lipoprotein receptor could inhibit the NLRP3-meidiated neurotoxic polarization of astrocytes and that increasing low-density lipoprotein receptor in astrocytes might represent a novel strategy for treating cerebral ischemic stroke.

关键词： inflammation ischemia/reperfusion injury ischemic stroke low-density lipoprotein receptor neuroprotective astrocytes neurotoxic astrocytes NLRP3 inflammasome polarization

Ru doping triggering reconstruction of cobalt phosphide for coupling glycerol electrooxidation with seawater electrolysis

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Journal of Energy Chemistry 2025年第1期100卷 317-326页

作者： Binglu Deng Jie Shen Jinxing Lu Chuqiang Huang Zhuoyuan chen feng Peng Yunpeng liu School of Materials Science and Hydrogen Energy Foshan University School of Chemistry and Chemical Engineering Guangzhou University Guangdong Key Laboratory for Hydrogen Energy Technologies

Seawater electrolysis is a promising approach for sustainable energy without relying on precious ***,the large-scale seawater electrolysis is hindered by low catalytic efficiency and severe anode corrosion caused by the harmful *** contrast to the oxygen evolution reaction （OER）and chlorin ion oxidation reaction （ClOR）,glycerol oxidation reaction （GOR） is more thermodynamically and kinetically favorable ***,a Ru doping cobalt phosphide （Ru-CoP2） is proposed as a robust bifunctional electrocatalyst for seawater electrolysis and GOR,for the concurrent productions of hydrogen and value-added *** in situ and ex situ characterization analyses demonstrated that Ru doping featured in the dynamic reconstruction process from Ru-CoP2to Ru-CoOOH,accounting for the superior GOR *** coupling GOR with hydrogen evolution was realized by employing Ru-CoP2as both anode and cathode,requiring only a low voltage of 1.43 V at 100 mA cm-2,which was 250 m V lower than that in alkaline *** work guides the design of bifunctional electrocatalysts for energy-efficient seawater electrolysis coupled with biomass resource upcycling.

关键词： Glycerol electrooxidation Hydrogen evolution Ru doping Cobalt phosphide Bifunctional electrocatalysts