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Influence of Si content and heat treatment on microstructure of Al-Fe-Si alloys

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China Foundry 2014年第5期11卷 418-422页

作者： Zhao Yuhua wang xiubin Liu Yulin wang Chao School of Materials Science and Engineering Shenyang Aerospace University

The effect of Si addition and heat treatment on the Al-5wt.%Fe al oy has been investigated by OM, SEM-EDS and XRD. The results show that the Si plays a significant role in refining the primary Al3Fe phase. It was found that the addition of 3.0wt.% Si made the al oy present the finest and wel -distributed primary Al3Fe phase, but the Al3Fe phase almost disappeared when 5wt.% Si was added. With further increase in the Si content, some Fe-rich phases appeared in the inter-grains and coarsened. In addition, the heat treatments exert a significant impact on the microstructural evolution of the Al-5wt.%Fe-5wt.%Si al oy. After heat treatment for 28 hours at 590 oC, the coarse platelet or blocky Fe-rich phase in Al-5wt.%Fe-5wt.%Si al oys was granulated; the phase transformation from metastable platelet Al3FeSi and blocky Al8Fe2Si to stable Al5FeSi had occurred. With the extension of heat treatment, the Si phase coarsened gradual y.

关键词： Al-Fe alloy Fe-rich primary phase silicon heat treatment

Planation Surfaces on the Tibet Plateau,China

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Journal of Mountain Science 2008年第4期5卷 310-317页

作者： ZHANG Xinbao HE xiubin wang Yangchun LONG Yi Institute of Mountain Hazards and Environment CAS Chengdu 610041 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment GAS Xi＇an 710075 China Graduate University of the Chinese Academic of Sciences Beijing 100039 China

A planation hypothesis is proposed to explain landform evolution of the Tibet Plateau. A denudation threshold （T）, the maximum potential denudation rate for a certain type of rock, is introduced to explain the combined effects of lithology and tectonics on landform evolution. If the tectonic uplifting rate （U） is equal to or less than the threshold rate （U ≤ T）, the tectonic uplifting and terrain denudation are in dynamic equilibrium, and landforms are in a steady state. The end product should be planation surfaces whether the original landforms are flat plains or deeply dissected mountains. If U 〉 T, uplift and denudation are not able to reach a dynamic equilibrium state. The plateau surface is mostly underlain by soft rocks, such as the Mesozoic epimetamorphic argillites and Tertiary sedimentary rocks, while the mountain ranges comprise hard rocks, such as granite, gneiss and limestone. In soft rock regions, hills are low with a relative relief of mostly less than 100 m and the slopes are gentle at a gradient of 〈200. In contrast, hills can maintain steep slopes in hard rock regions. The Tibet Plateau has been under an equilibrium condition between tectonic uplifting and denudation except for the mountain ranges. The plateau might have reached the present altitudes before the Quaternary.

关键词： planation denudation threshold landform evolution Tibet Plateau China

Hyperbaric oxygen therapy improves cognitive functioning after brain injury

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Neural Regeneration Research 2013年第35期8卷 3334-3343页

作者： Su Liu Guangyu Shen Shukun Deng xiubin wang Qinfeng Wu Aisong Guo Department of Rehabilitation Medicine Affiliated Hospital of Nantong University Department of Imaging Affiliated Hospital of Nantong University

Hyperbaric oxygen therapy has been widely applied and recognized in the treatment of brain injury; however, the correlation between the protective effect of hyperbaric oxygen therapy and changes of metabolites in the brain remains unclear. To investigate the effect and potential mechanism of hy- perbaric oxygen therapy on cognitive functioning in rats, we established traumatic brain injury models using Feeney＇s free falling method. We treated rat models with hyperbaric oxygen therapy at 0.2 MPa for 60 minutes per day. The Morris water maze test for spatial navigation showed that the average escape latency was significantly prolonged and cognitive function decreased in rats with brain injury. After treatment with hyperbaric oxygen therapy for 1 and 2 weeks, the rats＇ spatial learning and memory abilities were improved. Hydrogen proton magnetic resonance spectroscopy analysis showed that the N-acetylaspartate/creatine ratio in the hippocampal CA3 region was sig- nificantly increased at 1 week, and the N-acetylaspartate/choline ratio was significantly increased at 2 weeks after hyperbaric oxygen therapy. Nissl staining and immunohistochemical staining showed that the number of nerve cells and Nissl bodies in the hippocampal CA3 region was significantly increased, and glial fibrillary acidic protein positive cells were decreased after a 2-week hyperbaric oxygen therapy treatment. Our findings indicate that hyperbaric oxygen therapy significantly im- proves cognitive functioning in rats with traumatic brain injury, and the potential mechanism is me- diated by metabolic changes and nerve cell restoration in the hippocampal CA3 region.

关键词： neural regeneration brain injury hyperbaric oxygen magnetic resonance spectroscopy astrocytes immunohistochemistry choline creatine N-acetylaspartate CA3 region Morris water maze hippocampus neuroregeneration

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铝真空包的改进及碳素包块的设计

轻金属 2000年第9期 40-41页

作者：王秀彬山东平阴铝厂 250403

阐述了铝真空包内衬结构的改进 ,以及所设计铝真空包碳素包块在铝真空包内砌筑中的应用。铝真空包寿命提高了 5

关键词：铝真空包粘土砖碳素包块电解铝生产设计

基于金属护层模型参数辨识的电缆单相故障单端测距方法

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电力系统保护与控制 2019年第21期47卷 83-91页

作者：赵铁军王秀斌虞跃国网冀北电力有限公司秦皇岛供电公司

电缆大部分故障均与金属护层相关,仅考虑缆芯电气结构参数的模型无法实现护层相关的故障测距。为解决配电网电缆单相故障测距困难的问题,提出了基于金属护层模型参数辨识的电缆单相故障单端测距方法。以配电网单相故障零模等效网络作为... 详细信息

电缆大部分故障均与金属护层相关,仅考虑缆芯电气结构参数的模型无法实现护层相关的故障测距。为解决配电网电缆单相故障测距困难的问题,提出了基于金属护层模型参数辨识的电缆单相故障单端测距方法。以配电网单相故障零模等效网络作为辨识模型,将故障距离、过渡电阻、对地电容作为模型的未知参数,利用电缆单相接地故障后缆芯和护层中的暂态信息并结合故障状态网络和零模等效模型,建立时域测距方程作为参数辨识目标函数,用最小二乘算法进行最优参数求解,得到故障距离。ATP-EMTP仿真结果验证了所提方法的有效性,且测距精度高。

关键词：配电网电缆单相故障故障测距参数辨识最小二乘算法

耦合Sasa-Satsuma方程的Darboux-穿衣变换和半有理解

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应用数学学报 2024年第1期47卷 124-138页

作者：王秀彬田守富中国矿业大学数学学院徐州221116

本文主要研究可积的耦合Sasa-Satsuma方程,它可用于描述两个超短脉冲在双折射或双模光纤中的传输动力学.通过Darboux-穿衣变换,可以得到一类半有理解.这类解能够展示出怪波与呼吸波之间各种有趣的叠加场景.这些结果将有助于丰富和解释... 详细信息

本文主要研究可积的耦合Sasa-Satsuma方程,它可用于描述两个超短脉冲在双折射或双模光纤中的传输动力学.通过Darboux-穿衣变换,可以得到一类半有理解.这类解能够展示出怪波与呼吸波之间各种有趣的叠加场景.这些结果将有助于丰富和解释出现在光纤和色散介质中一些相关的非线性现象.

关键词：可积系统耦合Sasa-Satsuma方程 Darboux-穿衣变换半有理解

非零边界条件下离散Hirota方程的反散射变换研究

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数学学报（中文版） 2024年第6期67卷 1049-1076页

作者：王贵贤王秀彬韩波江苏科技大学理学院镇江212100 中国矿业大学数学学院徐州221116 哈尔滨工业大学数学学院哈尔滨150001

本文利用反散射变换法探索了具有非零边界条件的离散Hirota方程,同时求解了分支点和谱奇异点上的任意阶极点.基于鲁棒反散射变换构造的Darboux矩阵,相较于现存研究成果,避免了对谱参数极限处理步骤,从而简化了计算过程.最终详细推导了... 详细信息

本文利用反散射变换法探索了具有非零边界条件的离散Hirota方程,同时求解了分支点和谱奇异点上的任意阶极点.基于鲁棒反散射变换构造的Darboux矩阵,相较于现存研究成果,避免了对谱参数极限处理步骤,从而简化了计算过程.最终详细推导了几种有理解的紧化表达式,其中包含W-型孤子、呼吸波、以及高阶怪波解.并且通过绘制三维图和沿空间分量波的传播图,形象地展示了上述解的显著特征,此外,它们之间的相互作用也可直观地观察到.研究结果有助于解释相关的非线性波动现象,进而揭示其产生原理与机制.

关键词：离散Hirota方程反散射变换法 Riemann-Hilbert问题 Darboux变换

聚焦Kundu-Eckhaus方程中畸形波的奇异动力学行为研究

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数学物理学报（A辑） 2023年第3期43卷 785-794页

作者：王秀彬田守富中国矿业大学数学学院江苏徐州221116

该文基于Darboux变换的相关结果,利用变量分离法推导出了聚焦Kundu-Eckhaus方程的一般高阶畸形波解.然后通过一些图形详细地讨论了这些畸形波解的动力学行为.特别地,这里可以观察到一个四瓣形畸形波和三眼形畸形波是可以共存的,这是完... 详细信息

该文基于Darboux变换的相关结果,利用变量分离法推导出了聚焦Kundu-Eckhaus方程的一般高阶畸形波解.然后通过一些图形详细地讨论了这些畸形波解的动力学行为.特别地,这里可以观察到一个四瓣形畸形波和三眼形畸形波是可以共存的,这是完全不同于之前存在的四眼形畸形波.研究结果表明,该文所研究的畸形波结构比在著名的非线性Schrödinger方程中的畸形波结构更为丰富.

关键词：聚焦 Kundu-Eckhaus 方程变量分离方法畸形波

3.5t燃油熔铝炉炉门拱塌陷原因分析及改进预防措施

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轻金属 2003年第3期 43-45页

作者：王秀彬唐志文山东平阴铝厂山东平阴250412

对 3 .5t燃油熔铝炉炉门拱塌陷原因进行了分析 ,提出了七个方面的预防措施。

关键词：燃油熔铝炉炉门拱塌陷