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基于导纳响应的左特征结构配置振动主动控制

船舶力学 2024年第8期28卷 1277-1286页

作者：夏茂龙徐强李永正张彤彤张晓飞江苏科技大学船舶与海洋工程学院江苏镇江212000 中国船舶科学研究中心江苏无锡214082 陆军军事交通学院江苏镇江212003

主动控制可以通过施加控制力作用于结构系统来有效控制结构低频振动噪声,在振动噪声控制领域具有重要的意义。本文提出一种基于导纳响应配置左特征向量的主动控制方法,通过实际测量的结构导纳响应,利用振动系统左特征向量与激励之间的... 详细信息

主动控制可以通过施加控制力作用于结构系统来有效控制结构低频振动噪声,在振动噪声控制领域具有重要的意义。本文提出一种基于导纳响应配置左特征向量的主动控制方法,通过实际测量的结构导纳响应,利用振动系统左特征向量与激励之间的关系来实现结构振动主动控制。首先,基于导纳响应推导特征值与左特征向量的配置,无需建立结构的系统模型,或知道原结构系统的M、C、K矩阵;其次,利用左特征向量的冗余空间,将闭环系统的左特征向量配置成与激励力向量正交的形式,实现结构振动的主动控制;最后,通过数值算例验证此方法的有效性和正确性。

关键词：主动控制导纳响应左特征向量结构振动

Study on the Overload and Dwell-Fatigue Property of Titanium Alloy in Manned Deep Submersible

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China Ocean Engineering 2020年第5期34卷 738-745页

作者： WANG Ke WU li li yong-zheng SUN Xiao-peng School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

With the rapid development of ocean technology, the deep-sea manned submersible is regarded as a high-tech equipment for the exploration and exploitation of ocean resources. The safety of manned cabin has a decisive effect on the whole system. Ti-6 Al-4 V with the superior strength-to-weight ratio and corrosion resistance has been used for the manned cabin. The manned cabin experiences loading spectrum with different maximum stresses and different dwell time during their service life. The load sequence effects on dwell fatigue crack growth behavior of Ti-6 Al-4 V under different dwell time are investigated experimentally in this paper. The experimental results show that the crack tip plastic zone is enlarged by the dwell time and the overload retardation zone increases with dwell time under the same overload rate. A dwell fatigue crack growth model is proposed by modifying the crack tip plastic zone under the loading history with combinations of the single overload and dwell time factors are included in the modified model. Based on the experimental data, the overload retardation zone and the crack growth rates of Ti-6 Al-4 V are predicted by the modified model. A reasonable model for the load sequence effect on the dwell fatigue crack growth rates of Ti-6 Al-4 V is verified.

关键词： manned cabin dwell fatigue crack growth rate Ti-6Al-4V load sequence effect

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Ka频段100 W空间行波管研制

真空电子技术 2024年第4期 33-36页

作者：李泳铮赵树利马讯北京真空电子技术研究所北京100015

主要介绍了Ka频段100 W空间行波管最新研制情况,通过长寿命与高流通电子光学系统设计、高效率与高线性注波互作用综合优化技术、高效率能量回收多级降压收集极设计等措施,研制出带宽2 GHz、P≥100 W、η≥60%、饱和相移≤50°的数传用K... 详细信息

主要介绍了Ka频段100 W空间行波管最新研制情况,通过长寿命与高流通电子光学系统设计、高效率与高线性注波互作用综合优化技术、高效率能量回收多级降压收集极设计等措施,研制出带宽2 GHz、P≥100 W、η≥60%、饱和相移≤50°的数传用Ka频段频段空间行波管,并完成了鉴定试验。

关键词： Ka频段高效率高线性

Numerical Modelling of Wash Waves Generated by Ships Moving over An Uneven Bottom

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China Ocean Engineering 2023年第1期37卷 145-153页

作者： li Ming-xin YUAN Zhi-ming BAI Xu li yong-zheng CHENG yong TAO Long-bin School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Department of Naval Architecture Ocean and Marine EngineeringUniversity of StrathclydeGlasgow G11XQUK

Unsteady wash waves generated by a ship with constant speed moving across an uneven bottom topography are investigated by numerical simulations based on a Mixed Euler–Lagrange(MEL) method. The transition is accomplished by the ship traveling from the depth h1 into the depth h2 via a step bottom. A small tsunami would be created after this transition. However, the unsteady wave-making resistance induced by this new phenomenon has not been well documented by literature. Therefore, the main purpose of the present study is to quantify the effects of an uneven bottom on the unsteady wash waves and wave-making resistance acting on the ship. An upwind differential scheme is commonly used in the Euler method to deal with the convection terms under free-surface condition to prevent waves in the upstream. Evidently, it cannot be applied to the present problem due to upstream waves generated by the ship would be dampened by the upwind scheme. The central differential scheme provides more accurate results,but it is not unconditionally stable. An MEL method is therefore employed to investigate the upstream wave generated by the ship moving over the uneven bottom. Simulation results show that the hydrodynamic interaction between the ship and the uneven bottom could initiate an upstream tsunami, as well as unsteady wave-making resistance on *** unsteady wave-making resistance oscillates periodically, and the amplitude and period of the oscillations are highly dependent on speed and water depth.

关键词： uneven bottom upstream wave unsteady wave resistance numerical simulation periodic oscillation

Electroless deposition of Ni on template of halloysite and its magnetic property

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中国有色金属学会会刊：英文版 2004年第z1期14卷 152-156页

作者： FU Yu-bin ZHANG li-de zheng Ji-yong Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China Luoyang Ship Material Research Institute Luoyang 471039 China Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China Luoyang Ship Material Research Institute Luoyang 471039 China

Halloysite template, a ceramic substrate, is of a hollow cylindric structure, on which the fine Pd nanoparticles are uniformly formed by the reduction of palldate chloride to initiate electroless deposition. The electroless deposition of Ni is catalyzed by the Pd particles, which results in a uniform layer of Ni-P alloy on halloysite. The alloy is of a nanocrystalline structure, of which the average diameter is about 6 nm. After being heat-treated at 400 ℃, it contains both Ni and Ni12P5 crystal, meanwhile, the Ni crystal gets larger with an average size of 51.9 *** content of phosphorous in the Ni layer has a great influence on crystal structure. The metallized halloysite has a higher inherent coercive force, and a much lower saturation magnetization in its as-plated state, while after heattreatment, the inherent coercive force decreases drastically. These magnetic properties have great relationship with the superparamagnetism of Ni nanocrystalline and the stress anisotropy in Ni layer.

关键词： halloysite template electroless deposition Ni nanocrystalline inherent coercive force

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复合材料无人艇碰撞动力学数值仿真

舰船科学技术 2024年第6期46卷 81-85页

作者：李永正张思远李清张剑孔志宏崔凯江苏科技大学江苏镇江212100 上海外高桥造船海洋工程有限公司上海200120 华润燃气(上海)有限公司上海200120 陕西柴油机重工有限公司陕西兴平713105

针对复合材料无人艇碰撞损伤特性及耐撞性能优化问题,首先开展无人艇用复合材料力学性能试验研究,得到复合材料各项基本力学性能参数;在确保材料参数合理性的基础上,开展不同复合材料铺层角度下复合材料无人艇的耐撞性能数值仿真研究,... 详细信息

针对复合材料无人艇碰撞损伤特性及耐撞性能优化问题,首先开展无人艇用复合材料力学性能试验研究,得到复合材料各项基本力学性能参数;在确保材料参数合理性的基础上,开展不同复合材料铺层角度下复合材料无人艇的耐撞性能数值仿真研究,获得复合材料无人艇的碰撞力、位移、加速度以及主要构件的吸能,从而确定耐撞性能较优的复合材料无人艇材料铺层方案,为分析复合材料无人艇碰撞及优化无人艇耐撞性能提供了研究基础。

关键词：无人艇复合材料耐撞性能复合材料铺层角度

Combustion Synthesis of h-BN-SiC Ceramic Composites

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Chinese Journal of Aeronautics 2006年第B12期19卷 51-54页

作者： li Hong-bo zheng yong-ting ZHOU li-juan HANJie-cai Center for Composite Materials Harbin Institute of Technology Harbin 150001 China

The feasibility was demonstrated to fabricate h-BN-SiC ceramics through combustion synthesis of the mixture of boron carbide and silicon powders under 100 MPa nitrogen pressure. The mass fraction of BN and SiC in the combustion products were found to be 72 % and 28 % respectively. The thermodynamics of the synthesis reaction and the adiabatic combustion temperature were calculated on the theoretical ground. The bending strengths of the ceramics were measured to be 65.2 MPa at room temperature and 55 MPa at 1350℃ The phase composition and microstructure of the combustion products were identified by X-ray diffraction （XRD） and scanning electron microscopy （SEM）.

关键词： combustion synthesis high-temperature ceramic h-BN-SiC

Syntheses and Biological Activities of Ethyl N-Hydroxy-N-(substituted)phenyloxamates as KARI Inhibitors

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Chemical Research in Chinese Universities 2007年第3期23卷 280-283页

作者： WANG Bao-lei li zheng-ming li yong-hong WANG Su-hua Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

Nine ethyl N-hydroxy-N-（substituted） phenyloxamates （2a-2i）, based on the structure of the KARI inhibitor IpOHA, were synthesized. Their structures were established on the bases of 1^H NMR, IR, ESI-MS and elemental analyses. Among the nine compounds, four show in vitro inhibitory activity on rice KARI, with 2c and 2g[ Ki values of （35.2±4.9） and （49.4 ±6. 3） μmol/L] having similar activity to the precursor of IpOHA（A, Ki =34. 1±6. 7 μmol/L）. The results will be helpful to further molecular design of more potent KARI inhibitors.

关键词： KARI inhibitor IpOHA Phenyloxamate Synthesis Biological activity

带软骨膜的肋软骨支架在鼻综合整形术中的应用

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局解手术学杂志 2024年第8期33卷 727-731页

作者：钟爱李正勇陈俊杰四川大学华西医院美容整形烧伤外科四川成都610041

目的探讨一种全新的带软骨膜的肋软骨支架预搭建鼻综合整形术的临床应用效果。方法回顾性分析2017年12月至2022年12月我院采用带软骨膜的肋软骨支架预搭建行鼻综合整形术的40例患者临床资料。观察患者术后鼻尖张力及鼻小柱皮瓣血运、围... 详细信息

目的探讨一种全新的带软骨膜的肋软骨支架预搭建鼻综合整形术的临床应用效果。方法回顾性分析2017年12月至2022年12月我院采用带软骨膜的肋软骨支架预搭建行鼻综合整形术的40例患者临床资料。观察患者术后鼻尖张力及鼻小柱皮瓣血运、围术期并发症发生情况。基于患者手术前后的面部照片测量鼻背长度、鼻尖高度、鼻唇角变化,评价患者主观满意度。结果40例患者手术进展顺利,术中出血量少,无围术期并发症,术后伤口均一期愈合。随访12~36个月,未发现假体移位、假体脱出、软骨支架移位变形或弯曲;1例患者发生细菌感染,经对症治疗后伤口愈合。与术前比较,患者术后鼻背长度、鼻尖高度明显增加,鼻唇角明显增大,差异均有统计学意义(P<0.001)。在形态效果方面,患者术后主观满意度为97.5%。结论预搭建带软骨膜的肋软骨支架应用于鼻综合整形术安全可靠,效果较好,并发症少,患者满意度高。

关键词：鼻整形肋软骨支架鼻中隔鼻唇角鼻小柱