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Friction Wear Property of Brake Materials by Copper-based Powder Metallurgy With Various Brake Speeds

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材料热处理学报 2004年第5期25卷 126-129页

作者： LIUJian-xiu GAOHong-xia weiXiu-lan ZhengzhouUniversityofLightIndustry. MechanicalEngineeringInstituteZhengzhouChina

The experiment is conducted on MM-1000 friction test machine, which tests friction wear property of copper-based brake materials by powder metallurgy at different brake speeds. It shows that the coefficient of friction and wear volume are greatly influenced by brake speed. When the brake speed is 4000 r/min, which is a bit higher, the material still has a higher coefficient of friction with 0.47. When the brake speed is over 4000r/min, the coefficient of friction decreased rapidly. When the brake speed is 3000r/min, the material’s wear is in its minimum. That is to say no matter how higher or lower the brake speed is the wear volume is bigger relatively. With the brake speed of the lower one it mainly refers to fatigue wear; while of higher one it mainly refers to abradant and oxidation wear.

关键词：粉末冶金刹车铜材料磨损

Roles of Fas signaling pathway in vitamin E succinateinduced apoptosis in human gastric cancer SGC-7901 cells

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World Journal of Gastroenterology 2002年第6期8卷 982-986页

作者： Kun Wu Yao Li Yan Zhao Yu-Juan Shah wei xia lan Zhao,Department of Nutrition and Food Hygiene,Public Health School,Harbin Medical University,Harbin 150001,Heilongjiang Province,China wei-Ping Yu,Genetics Institute,Texas University of USA,Austin,USA Department of Nutrition and Food Hygiene Public Health School Harbin Medical University Heilongjiang Province China. wukun@***

AIM: To investigate the roles of Fas signaling pathway in vitamin E succinate-induced apoptosis in human gastric cancer SGC-7901 ***: Human gastric cancer SGC-7901 cells were treated with VES at 5, 10, 20 mg@L-1, succinic acid and vitamin E as vehicle control and condition media only as untreated (UT) control. Apoptotic morphology was observed by DAPI staining. Western blot analysis was applied to measure the expression of Fas, FADD and caspase-8 proteins. After the cells were transiently transfected with Fas and FADD antisense oligonucleotides, respectively, caspase-8 activity was determined by flurometric ***: The morphologically apoptotic changes were observed after VES treatment by DAPI staining. 23.7 % and 89.6 % apoptosis occurred after 24 h and 48 h of 20 mg@L-1 VES treatment, respectively. The protein levels of Fas, FADD and caspase-8 were evidently increased in a dose-dependent manner after 24 h of VES treatment. The blockage of Fas by transfection with Fas antisense oligonucleotides obviously inhibited the expression of FADD protein. After SGC-7901 cells were transfected with Fas and FADD antisense oligonucleotides, caspase-8 activity was obviously decreased (P＜0.01), whereas Fas blocked more than ***: VES-induced apoptosis in human gastric cancer SGC-7901 cells involves Fas signaling pathway including the interaction of Fas, FADD and caspase-8.

关键词：人胃癌细胞 SGC-7091细胞系 Ve琥珀酸酯维生素E 诱发凋亡 Fas信号通路作用机制

Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期68卷 111-127页

作者： Zhi-wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing xia xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

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洪湖历史时期人类活动的湖泊沉积环境响应

长江流域资源与环境 2005年第4期14卷 475-480页

作者：姚书春薛滨夏威岚中国科学院南京地理与湖泊研究所湖泊沉积与环境重点实验室

以洪湖北部和南部两个短柱钻孔(HN和HS)研究湖泊沉积,采用137Cs定年,沉积速率为0.155cm/a。沉积物的总有机碳、总氮、磷以及元素和磁化率等指标分析表明:1840年前洪湖地区人类活动较弱,在湖泊沉积物中基本没有早期的人类活动信号的记录;... 详细信息

以洪湖北部和南部两个短柱钻孔(HN和HS)研究湖泊沉积,采用137Cs定年,沉积速率为0.155cm/a。沉积物的总有机碳、总氮、磷以及元素和磁化率等指标分析表明:1840年前洪湖地区人类活动较弱,在湖泊沉积物中基本没有早期的人类活动信号的记录;1840年以后由于人口大量增加,人类活动增强,湖泊的营养水平有所增加,尤其是1950年以来沉积物中营养元素急剧增加;近50年来的湖泊营养程度的加重主要与流域内大量营养物质进入湖泊,以及大面积的围垦造成湖泊面积减小、自我调节能力降低有关。洪湖两孔的对比研究表明,不同区域之间存在着差异,可能与洪湖湖流作用及人类活动的影响差异有关。

关键词：人类活动环境响应历史时期 ^137Cs 自我调节能力湖泊沉积物沉积速率总有机碳洪湖地区营养水平营养元素营养物质湖泊面积对比研究 40年 50年分析表磁化率南部总氮

新建本科院校大学英语教学改革——《大学英语课程教学要求》与毕节学院校本研究

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毕节学院学报（综合版） 2007年第1期25卷 100-102页

作者：夏蔚兰毕节学院外语系贵州毕节551700

《大学英语课程教学要求》的颁行,引发了大学英语教学与研究的历史性变革,不同处境的院校虽有不同的起跑线,但却有共同的理念和方向——立足实际,关注个体,多管齐下,授之以渔。基于此,校本研究真正成为毕节学院大学英语教学改革与实践... 详细信息

《大学英语课程教学要求》的颁行,引发了大学英语教学与研究的历史性变革,不同处境的院校虽有不同的起跑线,但却有共同的理念和方向——立足实际,关注个体,多管齐下,授之以渔。基于此,校本研究真正成为毕节学院大学英语教学改革与实践的推动力。

关键词：毕节学院大学英语校本研究

商务合同英语句子结构特征及写作教学模式思考

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毕节学院学报（综合版） 2009年第5期27卷 73-76页

作者：林蔚夏蔚兰六盘水师专外语系贵州六盘水553004 毕节学院外语系贵州毕节551700

商务英语写作能力是从事对外贸易工作的重要技能之一。通过从分析国际商务合同句子结构特征入手,强调组句规范、符合契约文体,并推崇"以写促学"的教学理念。旨在提高学生草拟英语合同的准确性和规范性。

关键词：商务英语写作合同英语句子结构特征写作教学

Evaluation of left ventricular global systolic dysfunction on patients with hypertrophic remodeling by two-dimensional motion tracking of mitral annular displacement

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Evaluation of left ventricular global systolic dysfunction o...

CoTCPP integrates with BiOBr microspheres for improved solar-driven CO_(2)reduction performance

第二届长三角超声医学论坛暨2009年浙江省超声医学学术年会

作者： Department of Echocardiography,Chest Hospital of Shanghai Jiao Tong University Shanghai 200030,China Yan HUANG wei-hua WU Jing LU Song-xia wei lan MA xiao-yi XIE

Objective To investigate the preliminary value of mitral annular displacement(MAD) by twodimensional speckle tracking in evaluating left ventricular systolic dysfunction on patients with hypertrophic remodeling. Methods Thirty-seven patients with left ventricular hypertrophy(28 cases with hypertrophic cardiomyopathy,6 cases with hypertension and 3 cases with aortic valve stenosis) were studied as hypertrophic

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Green Energy & Environment 2025年第1期10卷 193-202页

作者： Lina Li Yi Zhang Gaopeng Liu Tiange wei Junze Zhao Bin Wang Mengxia Ji Yuanbin She Jiexiang xia Huaming Li School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu University301 Xuefu RoadZhenjiang212013China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse ***,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr *** as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO_(2) conversion into CO and CH_(4) upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,*** introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO_(2) *** metal Co^(2+) at the center of the porphyrin molecules also acts as adsorption center for CO_(2) molecules,accelerating the CO_(2) conversion into CO and *** possible mechanism of CO_(2) photoreduction was explored by in-situ FT-IR *** work offers a new possibility for the preparation of advanced photocatalysts.

关键词： BiOBr CoTCPP CO_(2)photoreduction Carriers transfer CO_(2)adsorption-activation

NF-κB和PTEN在子宫内膜异位症中的表达及其意义

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实用医学杂志 2013年第12期29卷 1939-1940页

作者：夏伟兰张广亮李娟南方医科大学南方医院妇产科广州市510515 广州市计生所 510510

目的:探讨NF-κB及PTEN在子宫内膜异位症中的表达及其意义。方法:采用免疫组化技术SP法检测异位内膜组(40例),在位内膜组(40例)及正常内膜组(30例)中NF-κB及PTEN蛋白的表达水平。结果:NF-κB在三组内膜中表达强弱依次为异位内膜>在位内... 详细信息

目的:探讨NF-κB及PTEN在子宫内膜异位症中的表达及其意义。方法:采用免疫组化技术SP法检测异位内膜组(40例),在位内膜组(40例)及正常内膜组(30例)中NF-κB及PTEN蛋白的表达水平。结果:NF-κB在三组内膜中表达强弱依次为异位内膜>在位内膜>正常内膜,其差异有显著统计学意义(P<0.01);PTEN在三组内膜中表达强弱依次为异位内膜<在位内膜<正常内膜,其差异有显著统计学意义(P<0.01)。结论:NF-κB和PTEN可能与子宫内膜异位症发生发展密切相关。

关键词：子宫内膜异位症 NF—κB PTEN