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部分螺旋桨工作状态下的船舶性能仿真研究 被引量:1
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作者 郝璇 赵玉娇 王兴龙 《设备管理与维修》 2020年第20期103-105,共3页
为预测部分螺旋桨工作状态下的船机桨特性,针对缺乏水动力实验数据的多机多桨船舶,区分内桨、外桨,分别估算锁轴、脱轴工况下螺旋桨的推力和扭矩;根据船机桨数学模型,在Matlab/Simulink中建立相应仿真模型,组成船舶运动模型。开发GUI界... 为预测部分螺旋桨工作状态下的船机桨特性,针对缺乏水动力实验数据的多机多桨船舶,区分内桨、外桨,分别估算锁轴、脱轴工况下螺旋桨的推力和扭矩;根据船机桨数学模型,在Matlab/Simulink中建立相应仿真模型,组成船舶运动模型。开发GUI界面,能灵活设置船机桨参数和外部环境参数。以某四机四桨船为仿真对象,设计典型工况实验,预测非正常情况下的船机桨匹配特性。 展开更多
关键词 锁轴 脱轴 GUI界面 仿真
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一种连接水轮发电机主轴“炮弹”螺栓的运用
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作者 李辉 刘继永 罗黎 《云南水力发电》 2023年第6期21-22,共2页
绿水河发电厂二级站1972年投产发电。额定容量:16 MW/台,类型为立式混流式。转速为750 r/min。机组与普通水轮发电机组不同之处在于整个发电机组由3段轴组成。转子与水轮机轴之间有一段连接,俗称中间轴。发电厂机组检修时,脱轴和连轴是... 绿水河发电厂二级站1972年投产发电。额定容量:16 MW/台,类型为立式混流式。转速为750 r/min。机组与普通水轮发电机组不同之处在于整个发电机组由3段轴组成。转子与水轮机轴之间有一段连接,俗称中间轴。发电厂机组检修时,脱轴和连轴是必不可少的重要工作。结合现场实际,绿水河检修班组制作出一种类似于“炮弹”的螺栓专用工具,在运用中取得较好效果。 展开更多
关键词 水电厂 水轮发电机组检修 连轴 脱轴 专用工具
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Research advancements of axonal remyelination in spinal cord injury 被引量:1
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作者 吴波 任先军 郭树章 《Journal of Medical Colleges of PLA(China)》 CAS 2007年第4期250-254,共5页
Spinal cord injuries(SCI)usually result in impairment of axonal conduction and sensorimotor function.There are no effective therapy to completely repair SCI.Axonal demyelination is very common as a pathologic change i... Spinal cord injuries(SCI)usually result in impairment of axonal conduction and sensorimotor function.There are no effective therapy to completely repair SCI.Axonal demyelination is very common as a pathologic change in SCI,and demyelination partly contributes to neural function impairment.So,it may be reasonable that remyelination of demyelinated axons become one of effective therapeutic targets for SCI treatment. Demyelination involves myelin breakdown and loss of myelin-forming cells(oligodendrocytes).The death of oligodendrocytes plays a key role in axonal demyelination in SCI.Recently a number of studies demonstrate that cell replacements could facilitate axonal remyelination and restore axonal conductive func- tion.Thus,it is expected that myelinogenetic cell transplantation(oligodendroglial lineage)will have good prospect as an effective therapy to improve axonal remyelination and restore neural function for SCI treat- ment in the near future. 展开更多
关键词 spinal cord injury DEMYELINATION axonal remyelination
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Recent advances in direct dehydrogenative biphenyl couplings
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作者 Fei Lv Zhu-Jun Yao 《Science China Chemistry》 SCIE EI CAS CSCD 2017年第6期701-720,共20页
Biphenyl moiety represents a unique structural motif of many natural and unnatural products with biological interests, and dehydrogenative couplings of two aryl C–H bonds under oxidative conditions is unambiguously t... Biphenyl moiety represents a unique structural motif of many natural and unnatural products with biological interests, and dehydrogenative couplings of two aryl C–H bonds under oxidative conditions is unambiguously the most efficient and direct preparation of these compounds. However, higher oxidation potential of benzene derivatives makes such oxidative couplings much more difficult than other arenes. Only very limited advances have been achieved on direct formation of the crucial C–C bond between two phenyl derivatives by dehydrogenative phenyl coupling in the last two decades. This article briefly summarized and commented a number of representative recent achievements in this attractive field, including homo-, cross-and intramolecular rearrangement and couplings, as well as their applications in organic synthesis. 展开更多
关键词 biphenyl dehydrogenative coupling oxidation arene C–H bond activation
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