中国科技论文在线

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2005年09月28日

【期刊论文】聚丙烯釜内釜外成核评价*

俞建勇，张广平，朱维平

合成树脂及塑料，2004，21 (1)：15，-0001，（）：

-1年11月30日

摘要

借助于热分析和力学性能测试考察了釜内与釜外添加成核剂对聚丙烯（PP）结晶行为和力学性能的影响。研究结果表明：2种添加方式对PP结晶温度影响不大，而釜内成核方式能更进一步提高结晶速率，成核PP的弯曲模量、低温抗冲击性能和热变形温度显著提高。

聚丙烯，成核剂，结晶行为，力学性能

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2005年09月28日

【期刊论文】Allometric Scaling and Instability in Electrospinning*

俞建勇， Ji-Huan He *， *， a， b， Yu-Qin Wan b， c， Jian-Yong Yu b

International Journal of Nonlinear Sciences and Numerical Simulation 5 (3),243-252, 2004，-0001，（）：

-1年11月30日

摘要

e intriguing and enduring problems after the technology was invented by Formhals in 1934. Regulatory mechanisms for controlling the radius of electrospun fibers are clearly illustrated in the different states. Generally, the relationship between radius r of jet and the axial distance z from nozzle can be expressed as an allometric equation of the form r～zb, the values of the scaling exponent (b) for the initial steady stage, instability stage, and terminal stage are respectively-1/2, -1/4, and 0. Allometry in economy, biology, turbulence, astronomy, neural resistance, conductive textile, and macromolecule viscosity is also briefly illustrated.

electrospinning， polymer， nanofiber， allometric scaling， turbulence， intelligent textile， Mark-Houwink relationship， Hodgkin-Huxley model， neural model， resistance， modified Ohm law

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2005年09月28日

【期刊论文】Scaling law in electrospinning: relationship between electric current and solution flow rate

俞建勇， Ji-Huan He a， b， *， Yu-Qin Wan c， Jian-Yong Yu c

Polymer 46(2005)2799-2801，-0001，（）：

-1年11月30日

摘要

A modified equation for charge conservation in electrospinning is suggested, and a nonlinear relation between the electric current of charged jet and the solution flow rate is obtained.

Electrospinning， Polymer， Allometric scaling

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2005年09月28日

【期刊论文】纳米碳酸钙增强聚丙烯共聚物

俞建勇，张广平，朱维平，戴干策

合成橡胶工业，2003-05-15, 26 (3):175，-0001，（）：

-1年11月30日

摘要

在反应器原位分散共聚中加入成核剂和纳米碳酸钙制备了增强型聚丙烯共聚物。增强型共聚物的冲击强度、弯曲应力和热变形温度大幅提高，拉伸强度也有所增加。同时结晶峰温度显著升高，且半结晶时间明显减少。

聚丙烯，原位聚合，纳米增强，物理机械性能，结晶速率

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2005年09月28日

【期刊论文】Compression Force Measured by Fiber Optic Smart Cellular Textile Composites

俞建勇， BIN YANG AND XIAO MING TAO ， JIANYONG Yu AND HoILUI HO

Textile Res. J. 74 (4), 305-313 (2004)，-0001，（）：

-1年11月30日

摘要

This paper is concerned with a study of compression force measured by smart cellular textile composites integrated with fiber Bragg grating (FBG) sensors. The novel design of the cellular textile composite structures integrated with FBG sensors is reported. Unit ceils of a cylindrical composite shell are fabricated from glass and polyester woven fabrics and epoxy, and are used to measure compression loads. When the composite shell unit is under pressure, the axial strain induced in the FBG sensor can be determined by the Bragg wavelength shift obtained fi' om an optic spectrum analysis. A theoretical analysis of the fiber' s axial strain focuses on compression load. The influences of environmental tem-perature, thickness, and effective moduli of the composites, and position and direction of the FBG sensors are discussed. The sensitivity of this device is 0.42nm/N (for the polyester composite) and 0.29nm/N (for the glass composite), and the measurement range is 0-2.1 N (PET) and 0-1.3 N (glass), respectively.

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