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Communications in Theoretical Physics 2006年第6X期46卷 1091-1100页

作者： ZHANG Wei-Guo dong chun-yan FAN En-Gui College of Science University of Shanghai for Science and Technology Shanghai 200093 China Institute of Mathematics Fudan University Shanghai 200433 China

In this paper, we discuss conditional stability of solitary-wave solutions in the sense of Liapunov for the generalized compound KdV equation and the generalized compound KdV-Burgers equations. Linear stability of the exact solitary-wave solutions is proved for the above two types of equations when the small disturbance of travelling wave form satisfies some special conditions.

关键词： generalized compound KdV equation generalized compound KdV-Burgers equation

Reactive Plasma Sprayed TiN Coating and Its Thermal Stability

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Journal of Iron and Steel Research International 2007年第5期14卷 71-75页

作者： ZOU dong-li yan Dian-ran HE Ji-ning LI Xiang-zhi dong yan-chun ZHANG Jian-xin School of Materials Hebei University of Technology Tianjin 300132 China School of Materials Science andEngineering Harbin Institute of Technology Harbin 150001 Heilongjiang China

TiN coating was prepared by reactive plasma spraying in the Ar and N2 containing plasma jet. The resuits of XRD show that the TiN coating consists of TiN and Ti3 O, neither Ti2 N nor TiO2 phases. The toughening mechanism was characterized by analyzing the SEM morphologies of the TiN coating＇s indentation of microhardness and fracture surfaces. The results indicate that the coating possesses a high toughness. The adhesion strength among the TiN layers is 25.88 MPa, which is slightly lower than that of the Ni/AI bonding coating. The oxidation process of the RPS TiN coating is TiN→Ti3 O→TiO2.

关键词： plasma spraying reactive plasma spraying TiN coating

Assessment of sediment yield in a small karst catchment by using 137Cs tracer technique

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International Journal of Sediment Research 2012年第4期27卷 547-554页

作者： dong-chun yan Xin-bao ZHANG An-bang WEN Xiu-bin HE Yi LONG Key Laboratory of Mountain Environment Evolution and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences Graduate University of Chinese Academy of sciences

There is very thin soil layer in karst rocky desertification areas in Southwest China,sediment deposition and sediment yield in the karst area affects the development of vegetation *** the present study,the137Cs technique was used to assess the rate of sediment deposition and sediment yield in a small karst ***137Cs inventory within the depression varied between 800 m-2and 2,200 Bq m-2,with the mean value of 1,500.1 Bq ***137Cs reference inventory at a nearby reference site was 805.9 Bq *** could be inferred to that sediment deposition had occurred in the *** mean depth of sediments deposition in the depression was 6 cm and the deposition rate was approximately 0.13 cm *** analysis of the topographic characteristics of the catchment revealed that the sediment deposition occurred mainly at the lower part of the small ***,there was a sinkhole in the depression,little sediment had drained out with runoff through the sinkhole,because the local people built ridges around the sinkholes for storing *** to this,sediment yield rate in the small catchment was estimated to be approximately 19.25 to 27.5 t km-2yr-1,and the extremely low sediment yield was maybe the main obstacle to vegetation restoration in karst rocky desertification areas.

关键词： 137Cs Sediment deposition Sediment yield Karst depression Southwest China

Synthesis and Self-assembling of Coumarin-based Low-molecular Weight Organogelators

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Chemical Research in Chinese Universities 2009年第2期25卷 178-182页

作者： CHEN Guo-jun XUE Peng-chong LU Ran SONG dong-po BAO chun-yan XU Ting-hua ZHAO Ying-ying College of Chemistry Jilin University Changchun 130012 P. R. China

Four coumarin derivatives（4a-4d） with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organogels in various organic fluids via ultrasound treatment or heating-cooling process, whereas compound 4c could only gel in a few mixed solvents and compounds 4a, 4b could not form organogel. The results from fluorescent and FT-IR spectra indicate that π-π interaction had an effect on the formation of the organogels of compound 4d besides H-bonding and van der Waals interaction, which were the driving forces for the self-assembling of compound 4c in gel state. The gel of compound 4d in toluene could emit strong fluorescence under UV irradiation and the [2＋2] cyclo-addition was suggested by ^1H NMR and fluorescence spectroscopy. This light-sensitive organogel might find application in optical materials.

关键词： Coumarin Organogelator Self-assembling [2+2] Cyclo-addition

基于专利分析的CO_(2)氧化乙苯脱氢技术研究进展及趋势

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现代化工 2024年第10期44卷 8-14页

作者：董雁春中石化(上海)石油化工研究院有限公司上海201208

在当今石化产业链、供应链加速重构的大背景下,全球能源化工均聚焦于绿色化工,作为绿色低碳发展路径之一的CO_(2)氧化乙苯脱氢技术备受瞩目。通过对CO_(2)氧化乙苯脱氢技术的技术特点、专利技术发展趋势、研究现状进行分析发现,高性能... 详细信息

在当今石化产业链、供应链加速重构的大背景下,全球能源化工均聚焦于绿色化工,作为绿色低碳发展路径之一的CO_(2)氧化乙苯脱氢技术备受瞩目。通过对CO_(2)氧化乙苯脱氢技术的技术特点、专利技术发展趋势、研究现状进行分析发现,高性能催化剂研发是该领域的研究重点,其中,钒基、铁基催化剂是其重点发展方向。应加强高性能催化剂研发、优化工艺路线、设计节能反应器等方面工作,促进高校院所与企业合作,加快CO_(2)氧化乙苯脱氢技术工业化步伐。

关键词： CO_(2) 乙苯苯乙烯催化剂工艺专利分析

微型中空纤维生物反应器肝细胞培养技术及其在药物肝毒性研究中的应用

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中国药理学与毒理学杂志 2009年第2期23卷 157-160页

作者：董春燕马璟上海医药工业研究院国家上海新药安全评价研究中心上海201203

传统的细胞培养方法中,肝细胞在体外不能实现高活性高密度的生长,因而无法模拟体内的三维立体生长环境,从而制约了药物肝毒性的体外评价;利用微型中空纤维凝胶包埋技术可以在体外固定肝细胞而模拟体内的立体环境。本文综述了微型中空纤... 详细信息

传统的细胞培养方法中,肝细胞在体外不能实现高活性高密度的生长,因而无法模拟体内的三维立体生长环境,从而制约了药物肝毒性的体外评价;利用微型中空纤维凝胶包埋技术可以在体外固定肝细胞而模拟体内的立体环境。本文综述了微型中空纤维凝胶包埋技术的发展及其在体外药物肝毒性方面的应用。

关键词：肝/毒性细胞培养中空纤维生物反应器

镉胁迫对三叶草种子形态指标、光合色素含量及酶活性的影响

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西部林业科学 2018年第6期47卷 35-39,44页

作者：董春燕青州市亚泰农业科技有限公司山东青州262500

采用水培试验研究不同浓度的镉胁迫对三叶草种子萌发、幼苗生长、光合色素含量及保护酶系统的影响,以探究三叶草对镉胁迫的敏感性和耐性。结果表明:镉能够抑制三叶草种子萌发和幼苗生长,在低浓度镉0. 5mmol/L时种子的发芽率、发芽势、... 详细信息

采用水培试验研究不同浓度的镉胁迫对三叶草种子萌发、幼苗生长、光合色素含量及保护酶系统的影响,以探究三叶草对镉胁迫的敏感性和耐性。结果表明:镉能够抑制三叶草种子萌发和幼苗生长,在低浓度镉0. 5mmol/L时种子的发芽率、发芽势、发芽指数、活力指数、苗长、芽长、胚轴长和根长均被抑制,较对照差异达极显著水平(P<0. 01),其浓度至3. 5mmol/L时三叶草种子的发芽势、活力指数和幼苗生长被完全抑制。叶绿素a、叶绿素b、叶绿素(a+b)和类胡萝卜素随镉浓度的增加而降低,与对照差异极显著(P<0. 01)。在镉浓度0-1. 5mmol/L范围内,保护酶SOD、CAT和POD活性升高,较对照分别提高36. 02%、33. 53%和93. 55%,继续增加镉浓度至2. 5mmol/L时酶活性呈下降趋势; APX活性在镉浓度0. 5mmol/L时最高,较对照提高80. 80%,继续增加镉浓度其活性开始下降,表明在低浓度镉(0-0. 5mmol/L)胁迫下,三叶草幼苗具有较强的抗氧化能力。

关键词：镉胁迫三叶草种子萌发幼苗生长光合色素保护酶

广义组合KdV方程与广义组合KdV-Burgers方程孤波解的条件稳定性

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上海理工大学学报 2006年第4期28卷 307-316页

作者：张卫国东春彦上海理工大学理学院上海200093

讨论了广义组合KdV方程和广义组合KdV Burgers方程的孤波解,在Liapunov意义下的条件稳定性.证明了当行波形式的微小扰动满足一定条件时,这两类方程的精确孤波解具有线性稳定性.

关键词：广义组合KdV方程广义组合KdV—Burgers方程孤波解条件稳定性 Liapunov特征指数

一类害虫流行病控制模型非常数正平衡解的存在性

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山东大学学报（理学版） 2011年第3期46卷 80-88页

作者：董春燕伏升茂西北师范大学数学与信息科学学院甘肃兰州730070

研究一类具有交错扩散的害虫流行病控制模型。讨论反应扩散系统惟一的正常数平衡解的全局稳定性,建立正平衡解上下界的先验估计,证明了交错扩散系统非常数正平衡解的存在性。

关键词：害虫控制模型交错扩散全局稳定性平衡解

等离子喷涂Al_2O_3与Al_2O_3/TiO_2涂层中的相变及涂层的耐腐蚀行为

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金属热处理 2005年第8期30卷 46-48页

作者：何继宁阎殿然董艳春李香芝刘艳改河北工业大学材料学院天津300130

研究了采用等离子喷涂法制备Al2O3涂层与Al2O3/TiO2复合涂层,以及喷涂前后涂层中相变及涂层的腐蚀行为。结果表明,在喷涂过程中有9%的-αAl2O3及45%的-βAl2O3转变成为-γAl2O3;机械混合的Al2O3与TiO2之间没有新相Al2TiO5形成,但有39%的... 详细信息

研究了采用等离子喷涂法制备Al2O3涂层与Al2O3/TiO2复合涂层,以及喷涂前后涂层中相变及涂层的腐蚀行为。结果表明,在喷涂过程中有9%的-αAl2O3及45%的-βAl2O3转变成为-γAl2O3;机械混合的Al2O3与TiO2之间没有新相Al2TiO5形成,但有39%的TiO2由金红石晶型转变为锐钛矿晶型。在5%沸腾的HCl内γ-Al2O3及-βAl2O3较-αAl2O3被优先腐蚀,TiO2相也同时被腐蚀。

关键词：等离子喷涂陶瓷涂层相变腐蚀