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RELATION BETWEEN DYNAMIC LOSS MODULUS AND DIFFUSION COEFFICIENT IN A MODIFIED PET FIBER
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作者 于建明 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第4期366-371,共6页
The mobility of polymer chain segments is shown to play a major role in the diffusion ofdisperse dyes in a copolymerization modified PET system, monoepoxy compoundCH_3 (CH_3),OCH_2CH--CH_2 modified PET. The rate of dy... The mobility of polymer chain segments is shown to play a major role in the diffusion ofdisperse dyes in a copolymerization modified PET system, monoepoxy compoundCH_3 (CH_3),OCH_2CH--CH_2 modified PET. The rate of dye diffusion (diffusion coefficient D) hasbeen related to the time-dependent mechanical property, dynamic loss modulus E', which iscontrolled by the mobility of chain segments. In this modified copolyester system, the variance ofamount of modifier in the copolyester fibers causes the change in disperse dye diffusion coefficientto fiber, and in the dynamic loss modulus of the fibers, but the relationship between the diffusionand the dynamic loss modulus is in agreement with the theoretical relation derived by Bell andDumbleton. The relation obtained in this paper is:Ln D=-2. 28Ln E'+26. 81 展开更多
关键词 dynamic loss modulus E″ Dyeing diffusion coefficient D Modified PET fiber
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Microstructure,magnetic domain and dynamic loss of surface-textured Fe-based nanocrystalline alloy 被引量:1
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作者 Aina He Jiawei Li +9 位作者 Mingkun Wang Anding Wang Yao Xiao Yaqiang Dong Hai Guo Rongrong Jiang Weixing Xia Lihong Dong Haidou Wang Jianya Ge 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第25期1-7,共7页
Heterogeneous coarse surface crystallites induced in the industrial Fe-rich nanocrystalline alloy is an obstacle for high-frequency and high-power commercial applications.Herein,the phase,crystal orientation,nanostruc... Heterogeneous coarse surface crystallites induced in the industrial Fe-rich nanocrystalline alloy is an obstacle for high-frequency and high-power commercial applications.Herein,the phase,crystal orientation,nanostructure and magnetic domain evolution of the surface-crystallized Fe-rich alloy were systematically investigated.Microstructure and inverse pole figures analysis confirms that the DOordered dendriticcrystallites bear<001>-oriented fiber texture before and after annealing at the free surface,while ultrafine nanocrystals are randomly oriented in the interior and wheel surface after annealing.As compared to zero magnetic-field-annealing,the transverse magnetic-field-annealing induces weakly oriented fiber texture and relatively uniform dendritic-crystallites at the surface,and uniform anisotropy in the interior and surface,which promotes smooth wall motion at the surface and magnetization rotation in the interior.This synergetic effect reduces the excess loss and leads reduction in dynamic loss at 1.0 T and10 kHz by 36%. 展开更多
关键词 Nanocrystalline alloy CRYSTALLIZATION TEXTURE Magnetic domain dynamic loss
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COMPUTATIONAL FLUID DYNAMICS RESEARCH ON PRESSURE LOSS OF CROSS-FLOW PERFORATED MUFFLER 被引量:15
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作者 HU Xiaodong ZHOU Yiqi +2 位作者 FANG Jianhua MAN Xiliang ZHAO Zhengxu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第2期88-93,共6页
The pressure loss of cross-flow perforated of physical modeling, simulation and data processing. muffler has been computed with the procedure Three-dimensional computational fluid dynamics (CFD) has been used to inv... The pressure loss of cross-flow perforated of physical modeling, simulation and data processing. muffler has been computed with the procedure Three-dimensional computational fluid dynamics (CFD) has been used to investigate the relations of porosities, flow velocity and diameter of the holes with the pressure loss. Accordingly, some preliminary results have been obtained that pressure loss increases with porosity descent as nearly a hyperbolic trend, rising flow velocity of the input makes the pressure loss increasing with parabola trend, diameter of holes affects little about pressure loss of the muffler. Otherwise, the holes on the perforated pipes make the air flow gently and meanly, which decreases the air impact to the wall and pipes in the muffler. A practical perforated muffler is used to illustrate the available of this method for pressure loss computation, and the comparison shows that the computation results with the method of CFD has reference value for muffler design. 展开更多
关键词 Perforated muffler Pressure loss Computational fluid dynamics (CFD) Porosity Flow velocity
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Effects of Interface on the Dynamic Hysteresis Loss and Static Mechanical Properties of Illite Filled SBR Composites 被引量:1
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作者 Zhe-Peng Wang Hao Zhang +2 位作者 Qiang Liu Shao-Juan Wang Shou-Ke Yan 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2022年第11期1493-1502,共10页
Despite growing interest in nano-sized fillers,micro-sized fillers with desired compatibility are still used for reinforcing rubbers,owing to their lower production cost and easier processing relative to nano-sized fi... Despite growing interest in nano-sized fillers,micro-sized fillers with desired compatibility are still used for reinforcing rubbers,owing to their lower production cost and easier processing relative to nano-sized fillers.Especially,the abundant and eco-friendly clay minerals are recognized as the materials of the twenty-first century.Herein,illite,a naturally occurring clay having dimension in micrometric scale,has been selected as filler to reinforce the SBR.To improve the compatibility of illite with SBR,the illite was modified by either bis[3-(triethoxysilyl)propyl]tetrasulfide(Si69-illite)or 3-mercaptopropyltriethoxysilane(KH580-illite).The interfacial interactions of SBR composites filled with pristine illite(illite/SBR)and Si69-illite(Si69-illite/SBR),or KH580-illite(KH580-illite/SBR)were characterized by bound rubber content and Payne effect measurements,while dynamic hysteresis losses of these uncured and cured composites were also analyzed under various strain amplitudes.It was found that the filler-rubber interactions were greatly improved for Si69-illite/SBR and KH580-illite/SBR systems compared to the illite/SBR composite.This leads to an increment of modulus at 300%strain of the composites from 3.46 MPa for illite/SBR to 7.70 MPa for Si69-illite/SBR and12.96 MPa for KH580-illite/SBR.Moreover,lower rolling resistance and better wear resistance without compromising wet traction of Si69-illite/SBR and KH580-illite/SBR have been achieved.This demonstrates the high possibility of Si69 and KH580 modified illites as promising alternative fillers for reinforcing rubbers. 展开更多
关键词 ILLITE SBR Composite dynamic hysteresis loss Static mechanical properties
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Dendritic Learning and Miss Region Detection-Based Deep Network for Multi-scale Medical Segmentation
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作者 Lin Zhong Zhipeng Liu +2 位作者 Houtian He Zhenyu Lei Shangce Gao 《Journal of Bionic Engineering》 SCIE EI CSCD 2024年第4期2073-2085,共13页
Automatic identification and segmentation of lesions in medical images has become a focus area for researchers.Segmentation for medical image provides professionals with a clearer and more detailed view by accurately ... Automatic identification and segmentation of lesions in medical images has become a focus area for researchers.Segmentation for medical image provides professionals with a clearer and more detailed view by accurately identifying and isolating specific tissues,organs,or lesions from complex medical images,which is crucial for early diagnosis of diseases,treatment planning,and efficacy tracking.This paper introduces a deep network based on dendritic learning and missing region detection(DMNet),a new approach to medical image segmentation.DMNet combines a dendritic neuron model(DNM)with an improved SegNet framework to improve segmentation accuracy,especially in challenging tasks such as breast lesion and COVID-19 CT scan analysis.This work provides a new approach to medical image segmentation and confirms its effectiveness.Experiments have demonstrated that DMNet outperforms classic and latest methods in various performance metrics,proving its effectiveness and stability in medical image segmentation tasks. 展开更多
关键词 Medical image segmentation Dendritic learning Deep supervision dynamic focal loss
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RF thermal and new cold part design studies on a TTF-Ⅲ input coupler for Project-X 被引量:2
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作者 PEI Shi-Lun Chris E Adolphsen +2 位作者 LI Zeng-Hai Nikolay A Solyak Ivan V Gonin 《Chinese Physics C》 SCIE CAS CSCD 2012年第2期173-178,共6页
An RF power coupler is one of the key components in a superconducting (SC) linac. It provides RF power to the SC cavity and interconnects different temperature layers (1.8 K, 4.2 K, 70 K and 300 K). The TTF-Ⅲ cou... An RF power coupler is one of the key components in a superconducting (SC) linac. It provides RF power to the SC cavity and interconnects different temperature layers (1.8 K, 4.2 K, 70 K and 300 K). The TTF-Ⅲ coupler is one of the most promising candidates for the High Energy (HE) linac of Project X, but it cannot meet the average power requirements because of the relatively high temperature rise on the warm inner conductor, so some design modifications will be required. In this paper, we describe our simulation studies on the copper coating thickness on the warm inner conductor with RRR values of 10 and 100. Our purpose is to rebalance the dynamic and static loads, and finally lower the temperature rise along tbe warm inner conductor. In addition, to get stronger coupling, better power handling and less multipacting probability, one new cold part design was proposed using a 60 mm coaxial line; the corresponding multipacting simulation studies have also been investigated. 展开更多
关键词 RF thermal effect TTF-Ⅲ input coupler multipacting dynamic RF power loss static thermal loss
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Characteristics of motorized spindle supported by active magnetic bearings 被引量:6
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作者 Xie Zhenyu Yu Kun +2 位作者 Wen Liantang Wang Xiao Zhou Hongkai 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1619-1624,共6页
A motorized spindle supported by active magnetic bearings(AMBs) is generally used for ultra-high-speed machining. Iron loss of radial AMB is very great owing to high rotation speed, and it will cause severe thermal ... A motorized spindle supported by active magnetic bearings(AMBs) is generally used for ultra-high-speed machining. Iron loss of radial AMB is very great owing to high rotation speed, and it will cause severe thermal deformation. The problem is particularly serious on the occasion of large power application, such as all electric aero-engine. In this study, a prototype motorized spindle supported by five degree-of-freedom AMBs is developed. Homopolar and heteropolar AMBs are independently adopted as radial bearings. The influences of the two types of radial AMBs on the dynamic characteristics of the motorized spindle are comparatively investigated by theoretical analysis, test modal analysis and actual operation of the system. The iron loss of the two types of radial AMBs is analyzed by finite element software and verified through run-down experiments of the system. The results show that the structures of AMB have less influence on the dynamic characteristics of the motorized spindle. However, the homopolar structure can effectively reduce the iron loss of the radial AMB and it is useful for improving the overall performance of the motorized spindle. 展开更多
关键词 dynamic characteristics Finite element analysis loss Magnetic bearings Modal analysis Spindle design
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