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Effect of flame conditions on abrasive wear performance of HVOF sprayed nanostructured WC-12Co coatings

中国有色金属学会会刊：英文版 2004年第Z1期14卷 72-76页

作者： WANG Yu-yue li chang-jiu MA jian YANG Guan-jun State Key Laboratory for Mechanical Behavior of Materials Xi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China

Nanostructured WC-12Co coatings were deposited by high velocity oxy-fuel (HVOF) spraying with an agglomerated powder. The effect of flame conditions on the microstructure of the nanostructured coatings was investigated. The wear properties of the coatings were characterized using a dry rubber-wheel wear test. The results show that the nanostructured WC-Co coatings consist of WC, W2C, W and an amorphous binder phase. The microstructure of the coating is significantly influenced by the ratio of oxygen flow to fuel flow. Under the lower ratio of oxygen/fuel flow, the nanostructured coating presents a relative dense microstructure and severe decarburization of WC phase occurs during spraying. With increasing ratio of oxygen/fuel flow, the bonding of WC particles in the coating becomes loose resulting from the original structure of feedstock and the decarburization of WC becomes less owing to limited heating to the powder. Both the decarburization of WC particles in spraying and the bonding among WC particles in the coatings affect the wear performance. The examination of the worn surfaces of the nanostructured coatings reveals that the dominant wear mechanisms would be spalling from the interface of WCCo splats when spray particles undergo a limited melting. While the melting state of the spray particles is improved,the dominant wear mechanisms become the plastic deformation and plowing of the matrix and spalling of WC particles from the matrix.

关键词： high velocity oxy-fuel spraying nanostructure abrasive wear performance WC-Co coating

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The ORF 113 of Heliocoverpa armigera Single Nucleopolyhedrovirus Encodes a Functional Fibroblast Growth Factor

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Virologica Sinica 2008年第5期23卷 321-329页

作者： Xiang li chang-yong liANG jian-hua SONG Xin-wen CHEN State Key Laboratory of Virology Wuhan Institute of Virology the Chinese Academy of Sciences Wuhan430071 China

Fibroblast growth factor (FGF) is a key regulator of developmental processes. A FGF homolog (vFGF) is found in all lepidopteran baculoviruses. Autographa californica nucleopolyhedrovirus (AcMNPV) and Bombyx mori NPV (BmNPV) vFGFs are chemotactic factors. Here we analyzed the vfgf of Helicoverpa armigera NPV (HearNPV), a group II NPV. The HearNPV vfgf transcripts were detected from 18 to 96 h post-infection (hpi) of Hz-AM1 cells with HearNPV and encoded a 36 kDa protein, which was secreted into the culture medium. HearNPV vFGF had strong affinity to heparin, a property important for FGF signaling via an FGF receptor. Unlike its AcMNPV homolog, HearNPV vFGF specially chemoattracted Hz-AM1, but not other insect cells such as Sf9 and Se-UCR and not the mammalian cells 293 and HepG2. HearNPV vFGF is also associated with the envelope of BV but is absent in occlusion-derived virus, which coordinated to the chemotatic activity analysis.

关键词： Helicoverpa armigera nucleopolyhedrovirus (HearNPV) Fibroblast growth factor (FGF) Baculovirus Open reading frame 113 (ORF 113)

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Analysis of Temperature Field and Thermal Crown of Roll During Hot Rolling by Simplified FEM

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Journal of Iron and Steel Research International 2006年第6期13卷 27-30,48页

作者： GUO Zhong-feng li chang-sheng XU jian-zhong liU Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Thermal crown of roll is an important factor, which affects strip profile. It is necessary to analyze the temperature field and thermal crown of roll for hot strip mill. A new simplified finite element method （FEM） was used to analyze the temperature field and thermal crown of roll, and corresponding models were built according to the practical boundary conditions. Transient roll temperature field and thermal crown were simulated by ANSYS FEM software with considering transient thermal contact and complex boundary condition. Temperature and thermal crown variations on roll surface nodes were obtained. The thermal crown results of roll obtained by FEM simulation were in good agreement with the measured data, indicating that simplified FEM models and results were correct.

关键词： temperature field thermal crown FEM roll

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Effect of Exogenous Ammonium on GlutamineSynthetase, Glutamate Synthase, and Glutamate Dehydrogenase in the Root of Rice Seedling

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Wuhan University Journal of Natural Sciences 1999年第3期4卷 358-362页

作者： li Ze-song Zhang Chu-fu lin Qing-hua Peng Jin li chang-jian He Guang-cun Peng Shao-bing John Bennett College of life Sciences Wuhan University Wuhan China International Rice Research Institute Makati City Philippines

Root biomass of rice seedlings was increased at lower concentration of exogenous NH 4 + , but it was decreased at higher concentration of exogenous NH 4 + . The level of free NH 4 + in the roots was accumulated gradually with the increase of NH 4 + concentration in the nutrient solution. The content of the soluble proteins was essentially constant at higher NH 4 + . The activities of glutamine synthetase (GS), NADH-dependent glutamate synthase (NADH-GOGAT), and NADH-dependent glutamate dehydrogenase (NADH-GDH) were risen with exogenous NH 4 + concentration at the lower NH 4 + concentration range. But the activities of GS and NADH-GOGAT were declined, and the level of NADH-GDH activity was kept constant under higher NH 4 + concentration. The GS/GDH ratio suggested that NH 4 + was assimilated by GS-GOGAT cycle under lower NH 4 + concentration, but NADH-GDH was more important for NH 4 + assimilation and detoxifying NH 4 + to the tissue cells at the higher NH 4 + level. According to the growth and the activity changes of these ammonium-assimilating enzymes of rice seedling roots, 10. 0 μg/mL NH 4 + -N in nutrient solution was more suitable to the rice growth.

关键词： ammonium glutamine synthetase glutamate synthase glutamate dehydrogenase rice root

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湿天然气凝结流动的双组分模型

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工程热物理学报 2018年第4期39卷 817-822页

作者：李长俊葛健西南石油大学石油与天然气工程学院成都610500

基于气液相间滑移的影响,建立了适用于湿天然气凝结系统的水蒸气-甲烷双组分自发凝结流动数理模型,研究了水蒸气在以甲烷为载气的超声速流动中的凝结规律,对比了不考虑相间滑移的单流体模型与加入了相间滑移因素的双组分模型在自发凝结... 详细信息

基于气液相间滑移的影响,建立了适用于湿天然气凝结系统的水蒸气-甲烷双组分自发凝结流动数理模型,研究了水蒸气在以甲烷为载气的超声速流动中的凝结规律,对比了不考虑相间滑移的单流体模型与加入了相间滑移因素的双组分模型在自发凝结过程中的凝结规律的区别,分析了压力、温度对湿天然气在Laval喷管中自发凝结的影响.结果表明,湿天然气中相间滑移作用对凝结参数影响较大,本文建立的包含相间滑移因素的双组分模型能更准确的预测湿天然气的凝结特性;在凝结初始阶段相间滑移速度较大达到7.2 m/s,对湿天然气的自发凝结规律影响较大,随凝结过程的不断进行气液两相逐渐达到平衡,相间滑移速度逐渐降低至1.8 m/s;随入口温度的降低、入口压力的升高最大凝结成核率位置向入口方向移动。

关键词：超音速凝结相间滑移双组分

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分子包埋纳米粒子薄膜阻变特性研究进展

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物理学报 2017年第1期66卷 1-18页

作者：李建昌邵思佳东北大学真空与流体工程技术研究中心沈阳110819

有机分子包埋纳米粒子阻变薄膜是信息存储领域的研究热点之一,本文从器件电极、介质层结构、纳米粒子种类、阻变机理和柔性弯折等方面,综述了其近年来的研究进展.电极/分子及分子/纳米粒子界面性质对器件阻变特性影响较大,但影响规律及... 详细信息

有机分子包埋纳米粒子阻变薄膜是信息存储领域的研究热点之一,本文从器件电极、介质层结构、纳米粒子种类、阻变机理和柔性弯折等方面,综述了其近年来的研究进展.电极/分子及分子/纳米粒子界面性质对器件阻变特性影响较大,但影响规律及界面调控机理仍待探究;分子结构与纳米粒子的种类、尺度及分布可改变膜内界面性质进而影响阻变特性;器件阻变机理主要包括导电细丝、电荷俘获与释放和电荷转移三种,其中导电细丝又分金属、氧空位和碳细丝.分子包埋纳米粒子薄膜阻变研究现多停留在小规模和静态器件方面,下一步应从连续卷绕制备、纳米粒子分布精确控制和耐弯扭特性等方面深入研究,为实现大面积、低成本、高柔性阻变存储器奠定基础.

关键词：阻变存储有机薄膜有机/无机界面柔性电子

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Long-term results of single-procedure catheter ablation for atrial fibrillationin pre-and post-menopausal women

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Journal of Geriatric Cardiology 2014年第2期11卷 120-125页

作者： Tao liN Xing DU Rong BAI Ying-Wei CHEN Rong-Hui YU De-Yong LONG Ri-Bo TANG Cai-Hua SANG Song-Nan li chang-Sheng MA jian-Zeng DONG Department of Cardiology Beijing Anzhen Hospital Capital Medical University Anzhen Road Chao Yang District Beijing 100029 China

Objectives To address whether menopause affects outcome of catheter ablation （CA） for atrial fibrillation （AF） by comparing the safety and long-term outcome of a single-procedure in pre-and post-menopausal women. Methods A total of 743 female patients who underwent a single CA procedure of drug-refractory AF were retrospectively analyzed. The differences in clinical presentation and outcomes of CA for AF between the pre-menopausal women （PreM group, 94 patients, 12.7%） and the post-menopausal women （PostM group, 649 patients, 87.3%） were assessed. Results The patients in the PreM group were younger （P＆lt;0.001） and less likely to have hypertension （P＆lt;0.001） and diabetes （P=0.005） than those in the PostM group. The two groups were similar with regards to the proportion of concomitant mitral valve regurgitation coronary artery disease, left atrium dimensions, and left ventricular ejection fraction. The overall rate of complica-tions related to AF ablation was similar in both groups （P=0.385）. After 43 （16-108） months of follow-up, the success rate of ablation was 54.3%in the PreM group and 54.2%in the PostM group （P=0.842）. The overall freedom from atrial tachyarrhythmia recurrence was simi-lar in both groups. Menopause was not found to be an independent predictive factor of the recurrence of atrial tachyarrhythmia. Conclusions The long-term outcomes of single-procedure CA for AF are similar in pre-and post-menopausal women. Results indicated that CA of AF appears to be as safe and effective in pre-menopausal women as in post-menopausal women.

关键词： Atrial fibrillation Catheter ablation Follow-up Menopausal woman

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中国农业补贴法律制度的具体设计——以生存权和发展权平等为中心

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河北法学 2009年第9期27卷 13-27页

作者：李长健华中农业大学文法学院湖北武汉430070

生存和发展问题是人类自身最基本的问题,"三农"问题的本质就是农民生存利益和发展利益的实现与发展。现有的农业补贴制度对发展中成员的生存权和发展关注不多,还无法实现发展中成员的生存和发展问题。我们需要以生存权和发展权平等为中... 详细信息

生存和发展问题是人类自身最基本的问题,"三农"问题的本质就是农民生存利益和发展利益的实现与发展。现有的农业补贴制度对发展中成员的生存权和发展关注不多,还无法实现发展中成员的生存和发展问题。我们需要以生存权和发展权平等为中心对农业补贴法律制度进行创新性发展。通过对国外相关制度的比较借鉴,构建以生存权和发展权平等为中心的"黄箱"农业补贴法制度;通过对多哈回合中"蓝箱"改革的研究,构建以生存权和发展权平等为中心的"蓝箱"农业补贴法制度;从"绿箱"补贴的十一个内容,结合中国实施情况,构建中国以生存权和发展权平等为中心的"绿箱"农业补贴法制度;由于现有的农业补贴制度的局限性和农业发展的需要,创新性地建构以生存权和发展权平等为中心的"白箱"农业补贴法律制度。

关键词：农业补贴生存权和发展权平等制度设计 “白箱”补贴互补性权利义务国际协调

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长江中游城市群土地利用效率测算:现实机理与时空分异

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中国人口·资源与环境 2017年第12期27卷 157-164页

作者：李长健苗苗华中农业大学文法学院湖北武汉430070 华中农业大学经济管理学院湖北武汉430070

为揭示长江中游城市群土地利用效率的现实机理与时空分异特征,探索区域协调、绿色发展、适度开放、资源共享意义下的城市土地利用思路,以四元作用异样度即经济增长度、社会发展度、资源持续度、环境友好度为效率评价法则,引入考虑非期... 详细信息

为揭示长江中游城市群土地利用效率的现实机理与时空分异特征,探索区域协调、绿色发展、适度开放、资源共享意义下的城市土地利用思路,以四元作用异样度即经济增长度、社会发展度、资源持续度、环境友好度为效率评价法则,引入考虑非期望产出的双目标DEA-SBM模型,对2001—2014年土地利用数据进行测算。结果表明:城市群土地利用效率整体上升、局部回落,"一主两副"土地利用格局分化显著,城市群内部土地利用效率离散水平较高;土地利用呈现较不稳定的空间正相关性,以低低型和低高型聚集为主,受局部不稳定因素影响的城市逐渐增多;土地利用非综合有效表现为纯技术效率有效而规模效率无效。由此,城市土地利用与社会经济效益、资源环境效益在不断的调和与适应,但区域土地利用效率发展水平并不同步,低效城市阻抑区域土地利用效率的整体发展进程,且土地要素投入规模与最优投入规模之间仍存在差距。为推动流域土地利用效率的提升,建设开放竞争、统一有序的建设用地市场,以城市群为单位进行土地功能分区,外力促进要素流动与区位互补、内力协调经济社会发展与资源环境可持续,形成以"中心+核心"城市为主体、"流域治理+部门协同"为手段的土地利用轴带。

关键词：土地利用效率时空分异双目标DEA一SBM模型四元作用异样度流域土地利用轴带

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Design of Welding with Trailing Peening System for Reaction Nitrogen Arc Welding Cladding

Design of Welding with Trailing Peening System for Reaction ...

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第三届数字制造与自动化国际会议

作者： li Xiong-zhuang Hao jian-jun li jian-chang Zhao jian-guo Ma Yue-jin Baoding Tianwei Electric Wire Co. Ltd Agriculture University of Hebei

In order to reduce welding stress, decreased welding crack and improve coating performance, a set of complete computer control system was designed and applied to prepare TiCN cermet composite coating by process. The system, which consists of PC, SCM （AT89C52）, sensor, interface circuit, pneumatic rammer, corresponding mechanism and valves, can peen the welded seam by a pneumatic rammer which is controlled by the signal from data acquisition card. The system can easily adjust the peening frequency, force, distance, and angle able. The result show that the system can make coatings more inseparable and compacter, less weld defect, and the coatings have an excellent mechanical property.

关键词： welding with trailing peening aerodynamic hammer reaction nitrogen arc welding

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