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Multi-performance evaluation of high-throughput accelerated corrosion test for high-strength low-alloy 921A steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1260-1278页

作者： Cong-cong Du Ming-hua Qin Zhan-fang Wu dong-ling li Lei Zhao Xiang-yang li Hai-zhou Wang Beijing Advanced Innovation Center for Materials Genome Engineering National Center for Materials Service SafetyUniversity of Science and Technology BeijingBeijing100083China China Iron and Steel Research Institute Group Co. Ltd.Beijing100081China Beijing Advanced Innovation Center for Materials Genome Engineering Central Iron and Steel Research InstituteBeijing100081China

The corrosion behavior of high-strength low-alloy 921A steel in a simulated marine atmospheric environment was studied using a high-throughput experimental *** corrosion behavior,corrosion morphology,and corrosion products of 921A steels were analyzed using various techniques,including corrosion mass loss method,polarization curve,white-light interferometry,scanning electron microscopy,energy-dispersive spectrometry,microbeam X-ray fluorescence spectrometry,X-ray diffraction technique,and X-ray photoelectron *** test results indicated that 921A steel exhibits better corrosion resistance than Q450NQR1 steel in simulated harsh atmospheric environments,as evidenced by a lower corrosion mass loss rate throughout the corrosion *** corrosion products of both steels consisted ofα-FeOOH,Fe_(3)O_(4),andγ-FeOOH,withα-FeOOH being more prevalent in the rust layer of 921A steel than in Q450NQR1 *** inner rust layer of 921A steel also exhibited an appositional enrichment region of Cr,Ni,Mo,and V,leading to its superior corrosion resistance compared to that of Q450NQR1 *** efficacy of high-throughput accelerated corrosion experimental methods was highlighted for evaluating the corrosion resistance of steel materials in harsh environmental *** findings suggest that 921A steel exhibits better corrosion resistance compared to Q450NQR1 steel and has the potential to be more suitable in harsh marine atmospheric *** characterization of the rust layer structures and composition reveals the parallel enrichment of certain elements in the inner rust layer of 921A steel,which enhances its corrosion resistance.

关键词： Atmospheric corrosion High-throughput experimental method High-strength low-alloy steel Corrosion characteristics Rust layer Element enrichment

Characterization of the globular oxide inclusion ratings in steel using laser-induced breakdown spectroscopy

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Frontiers of physics 2016年第6期11卷 273-279页

作者： Yong Zhang Yun-Hai Jia Chun Yang dong-ling li Jia liu Yong-Yan Chen Ying liu Yi-Xiang Duan Research Center of Analytical Instrumentation Key Laboratory of Bio-Resource and Eco-Environment Ministry of Education College of Life Science Sichuan University Chengdu 610064 China Central Iron and Steel Research Institute Beijing 100081 China NCS Testing Technology Co. Ltd. Beijing 100094 China General Research Institute of Nonferrous Metals Beijing 100088 China

Grade assessment of steel is generally performed via the metallographic method, which is time-consuming and is not able to provide the elemental distribution information. In this paper, we present a method to measure the globular oxide inclusion ratings in steel using laser-induced breakdown spectroscopy (liBS). The measurement is performed in two basic steps: steel samples are polished using metallographic sand paper and the Al2O3 inclusion number and size distribution in a marked area are observed using scanning electron microscope/energy dispersive X-ray spectroscopy (SEM/EDS) for further liBS scanning analysis. The threshold intensity that distinguishes soluble aluminum and insoluble aluminum inclusions is determined using liBS combined with the SEM/EDS statistical data. Carbon steel (the sample number is S9256) and bearing steel (the sample number is GCr15) are analyzed in scanning mode, and the number of Al2O3 inclusions in different size ranges is obtained from the statistical information derived from the Al2O3 size calibration curve. According to heavy and thin series for globular oxide inclusions grade assessment, the method we propose is comparable to the traditional metallographic method in terms of accuracy; however, the process is simplified and the measurement speed is significantly improved.

关键词： laser-induced breakdown spectroscopy (liBS) globular oxide inclusion steel grade assessment elemental distribution

SYNTHESIS OF DERIVATIVES OF 3-β-D-XYLOPYRANOSYL-1,2,4-OXADIAZOLES

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Chinese Chemical Letters 1992年第8期3卷 597-600页

作者： ling Jiao dong li li ling Tai MA li He ZHANG School of Pharmaceutical Sciences,Beijing Medical University,Beijing 100083

The synthesis of derivatives of 3-β-D-xylopyranosyl-1,2,4-oxadiazoles is accomplished by condensing protected β-D-xylopyranosyl amidoxime with acid anhydrides or various substituted benzoyl chlorides in good *** structures of now derivatives were identified by spectra and elemental analysis. The stability of 1,2,4-oxadiazole ring and mechanism of cyclization were. investigated.

关键词： D-XYLOPYRANOSYL-1,2,4-OXADIAZOLES SYNTHESIS OF DERIVATIVES OF 3 台五

Isolation,Identification and Pathogenic Characteristics of Duck Hepatitis Virus Isolates

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Animal Husbandry and Feed Science 2010年第8期2卷 37-39页

作者： GAO Ya-dong ling Hong-li dong Rui-e SUN Hai-xin Qingdao Contient Pharmaceutical Group Boitech Biopharmaceutical Co. Ltd. Qingdao 266114 China

[ Objective] The aim of this study was to determine and analyze the pathogen and the reasons of duck viral hepatitis which is prevalent recently and difficult to control. [Method] Viruses were isolated from livers and spleens of ducks with typical clinical symptoms in linyi, Weifang, Binzhou and other regions of Shandong Province. The pathogenic characteristics were observed by inoculation in chicken or duck embryo, RT- PCR, serological test, and duck regression. [ Result] Four duck hepatitis virus （DHV） strains were isolated, and the 5th passage allantoic fluid contained 10^3.41 -10^5.20 ELD50/mI. The serum cross protection rate was 20% -80% between the DHV stains and DHV type I. The mortalities of 4- day-old healthy ducks challenged by these four stains were 50% -100%. All challenged ducks had typical lesions of duck viral hepatitis, and the death peak appeared after 24-48 h. [Conclusion] The virulence of different DHV isolates has regional difference.

关键词： Duck hepatitis virus Identification Isolation Virulence

呈现框架与消费者选择:消费者知识与促销的作用——以延保产品为例

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经济经纬 2012年第6期29卷 97-100页

作者：董伶俐河南财经政法大学工商管理学院河南郑州450002 上海财经大学国际工商管理学院上海200433

笔者采用2个组间实验设计,研究呈现框架对消费者选择的影响,并以前景理论和心理账户理论为基础,研究消费者知识和促销活动的不同调节作用。结果表明:呈现框架对消费者购买意愿影响显著。相比减法呈现框架,加法呈现框架下消费者知识的调... 详细信息

笔者采用2个组间实验设计,研究呈现框架对消费者选择的影响,并以前景理论和心理账户理论为基础,研究消费者知识和促销活动的不同调节作用。结果表明:呈现框架对消费者购买意愿影响显著。相比减法呈现框架,加法呈现框架下消费者知识的调节作用显著;当主体产品进行促销时,无论是在加法框架下还是在减法框架下,消费者购买延保产品的意愿都明显增强。因此企业应根据这些特点制定相应营销策略,以提高新产品的销量。

关键词：呈现框架消费者选择消费者知识促销延保产品

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河南吸引外商直接投资的决定因素分析

经济经纬 2008年第5期25卷 61-63页

作者：董伶俐河南财经学院工商管理学院河南郑州450011

近年来,在开放带动经济发展的战略下,河南利用外商直接投资呈逐年上涨趋势。本文利用河南省1985年至2007年FDI的数据表明了这一趋势,并借助于"河南最佳投资城市"推介评选活动的实证结果分析了河南吸引外商直接投资的决定因素:区位和自... 详细信息

近年来,在开放带动经济发展的战略下,河南利用外商直接投资呈逐年上涨趋势。本文利用河南省1985年至2007年FDI的数据表明了这一趋势,并借助于"河南最佳投资城市"推介评选活动的实证结果分析了河南吸引外商直接投资的决定因素:区位和自然资源、基础设施和经济发展环境、以及产业集群等。

关键词：河南 FDI 决定因素

触觉体验对消费者购买决策判断的影响:兼论NFT与决策环境的调节作用

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经济经纬 2017年第5期34卷 123-127页

作者：董伶俐河南财经政法大学工商管理学院河南郑州450002

旨在研究触觉体验对于消费者购买决策的影响,并进一步研究了NFT和决策环境的不同调节作用。结果表明:触觉体验对消费者购买决策判断有显著的正向影响;NFT的调节作用显著,相比低NFT消费者,高NFT消费者的购买决策判断受触觉体验影响更显著... 详细信息

旨在研究触觉体验对于消费者购买决策的影响,并进一步研究了NFT和决策环境的不同调节作用。结果表明:触觉体验对消费者购买决策判断有显著的正向影响;NFT的调节作用显著,相比低NFT消费者,高NFT消费者的购买决策判断受触觉体验影响更显著;决策环境对于不同NFT的消费者有着不同的调节作用,对于低NFT消费者,决策环境对触觉体验的调节作用不显著,而对于高NFT消费者,决策环境的调节作用显著。

关键词：触觉体验消费者购买决策 NFT 决策环境

Corn Heterotic Group and Model in Heilongjiang of China

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Journal of Northeast Agricultural University(English Edition) 2009年第3期16卷 93-96页

作者： JIN Yi dong ling YU Tianjiang li Yan GUO Ran College of Agriculture Northeast Agricultural University Harbin 150030 China

The concept and research achievements of the heterotic group and model in corn were introduced briefly. The results showed that the domestic corn germplasm could be divided into three main heterotic groups and two main heterotic models. The research on corn germplasm in Heilongjiang Province could be concluded as three main heterotic groups and three main heterotic models. Some new opinions about corn heterotic group and heterotic model in Heilongjiang Province were proposed such as Northeast group and NortheastxLancaster model.

关键词： corn heterosis germplasm

Fibroblast growth factor-4 and hepatocyte growth factor induce differentiation of human umbilical cord blood-derived mesenchymal stem cells into hepatocytes

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World Journal of Gastroenterology 2005年第47期11卷 7461-7465页

作者： Xin-Qin Kang Wei-Jin Zang li-Jun Bao dong-ling li Tu-Sheng Song Xiao-li Xu Xiao-Jiang Yu Department of Genetics and Molecular Biology Mcclical School of Xi'an Jiaotong UniversityXi'an 710061 Shaanxi Province China Department of Pharmacology Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education School of Medicine Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China Department of Obstetrics and Gynecology First Hospital of Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China

AIM： To investigate the differentiation of human umbilical cord blood （HUCB）-derived mesenchymal stem cells （MSCs） into hepatocytes by induction of fibroblast growth factor-4 （FGF-4） and hepatocyte growth factor （HGF）, and to find a new source of cell types for therapies of hepatic diseases. METHODS： MSCs were isolated by combining gradient density centrifugation with plastic adherence. When HUCB-derived MSCs reached 70% confluence, they were cultured in Iscove modified Dulbecco medium （IMDM） supplemented with 10 mL/L FBS, 20 ng/mL HGF and 10 ng/mL FGF-4. The medium was changed every 4 d and stored for albumin, alpha-fetoprotein （AFP） and urea assay. Expression of CK-18 was detected by immunocytochemistry. Glycogen storage in hepatocytes was determined by PAS staining. RESULTS： By combining gradient density centrifugation with plastic adherence, we could isolate MSCs from 25.6% of human umbilical cord blood. When MSCs were cultured with FGF-4 and HGF, approximately 63.6% of cells became small, round and epithelioid on d 28 by morphology. Compared with the control, the level of AFP increased significantly from d 12 to 18.20：1=1.16 μg/L （t = 2.884, P〈0.05） in MSCs cultured with FGF-4 and HGF, and was higher （54.28±3.11 μg/L） on d 28 （t = 13.493, P〈0.01）. Albumin increased significantly on d 16 （t = 6.68, P〈0.01） to 1.02±0.15 μg/mL, and to 3.63±0.30 μg/mL on d 28 （t = 11.748, P〈0.01）. Urea （4.72±1.03 μmol/L） was detected on d 20 （t = 4.272, P〈0.01）, and continued to increase to 10.28±1.06　μmol/L on d 28 （t = 9.276, P〈0.01）. Cells expressed CK-18 on d 16. Glycogen storage was observed on d 24. CONCLUSION： HUCB-derived MSCs can differentiate into hepatocytes by induction of F-GF-4 and HGF. HUCB derived MSCs are a new source of cell types for cell transplantation therapy of hepatic diseases.

关键词： Mesenchymal stem cell Differentiation Hepatocyte