稀土荧光聚酰胺6固相缩聚前后的等温结晶动力学研究

通过原位聚合制备稀土荧光聚酰胺6(PA6)预聚体,再通过固相缩聚进一步提高其相对分子质量,利用示差扫描量热仪(DSC)对固相缩聚前后的样品进行等温结晶动力学研究.结果表明稀土荧光PA6的结晶速率随相对分子质量的增加而减小.而荧光粉在PA6等温结晶过程中,荧光粉起到了异相成核的作用,使得PA6的结晶速率增加.通过Arrhenius方程求得PA6和稀土荧光PA6的活化能.发现由于固相缩聚后样品的相对分子质量变大,分子问的作用力增大.固相缩聚前样品的活化能要比固相缩聚后的活化能高.而荧光粉限制了PA6大分子链的运动,稀土荧光PA6的结晶活化能要比PA6的活化能高.     

STS:从SSK到SEE

STS自SSK以来的显著特点是从规范走向描述,从重构走向解构。不过,这个领域的关注点近来转向研究如何积极介入公共领域的科学争论,规范问题重新受到重视。一种引起广泛讨论的规范性方案是SEE,它代表了STS最新的努力方向。     

三角异形丝的不对称传热模型的建立及分析

在分析了丝条传热过程的基础上，以三角形作为微分单元，详细分析了各微分单元之间的传热情况，建立了三角异形丝的传热模型，通过热平衡方程定量分析了各单元间的传热情况，进而可推导出各单元内部的温度分布，这里考虑了不对称传热系数对丝条冷却过程的影响，在丝条的迎风面和背风面采用不同的值，这可使得三角单元内部的温度分布更加接近实际情况，为计算机模拟出温度分布的结果提供了理论依据。     

高职《传感器与检测技术》课程教学的比较与改革

《传感器与检测技术》隶属于控制学科与工程学科,是理工类专业的一门重要课程。在中职、高职、本科院校的相关自动化类专业都有相应专业课程的设置,但在课程内容、实验、实训、教学效果等方面,有不同的编排和侧重,通过比较,我们将进一步领会高职教育为社会培养高素质技能型人才的目标,我们对该课程的教学内容、教学方法进行了大胆的改革和实践,使学生的学习积极性、技能及分析问题、解决问题的能力得到了较大提高,课程改革获得了很好的效果。     

[Bmim]BF4离子液体中丙烯腈-丙烯酸甲酯共聚物的合成及序列结构

以离子液体1-丁基-3-甲基咪唑氟硼酸盐（[Bmim]BR）作为溶剂，采用丙烯腈（AN）、丙烯酸甲酯（MA）作为单体，偶氮二异丁腈（AIBN）作为引发荆进行自由基共聚反应．利用^13C—NMR谱分析了共聚物中各三单元序列组的摩尔分数与单体投料摩尔分数的关系．通过计算得到的三单元序列摩尔分数推算得两单体的竞聚率为rA=0．33，rM=0．89．同时发现，[Bmim]BF4中AN和MA的链增长过程与Bernoulli模型有较大偏离，说明AN和MA在离子液体中的聚合过程中，增长链邻位上的链节对端基的选择性有较大影响，聚合物的各序列增长与反应时阀、单体摩尔分数及单体转化率有较大关系，并计算了受邻位链节影响的丙烯腈及丙烯酸甲酯的竞聚率：rMM=0．73，rAM=1．79，rAA=0．27，rMA=0．64．     

关于跳跃图的注记

证明若G是连通图,则J(G)≌G当且仅当G是G或Cor(K3)．通过引进边度概念,讨论连通图G的跳跃图J(C)是Hamilton图的一些充分条件．     

Alignment of Multi-walled Carbon Nanotubes in Polyacrylonitrile Fibers by Mechanical Drawing

Polyacrylonitrile(PAN)/multi-walled carbon nanotubes(MWNTs)nanocomposites were prepared by an in-situ polymerization method and the fibers from these composites were obtained by a wet-spinning process.The orientation behavior of MWNTs in the PAN fibers was investigated by X-ray diffraction and sound velocity methods.The dispersion and the alignment of the nanotubes were also studied by scanning electron microscopy.     

Atom Transfer Radical Polymerization of Acrylonitrile in Ionic Liquids

The controllable molecular weight and polydispersity of polyacrylonitriles(PANs) were synthesized in ionic liquids(ILs) by atom transfer radical polymerization(ATRP) using ethyl-2 bromopropionate(EPN-Br) as initiator and CuBr/pentamethyldiethylenetria-mine(PMDETA) as catalyst.The polydispersity index(PDI) in the ATRP of acrylonitriel(AN) in ILs is lower than 1.3.From the polymerization kinetics,plots of ln([M]0/[M]) with time show a linear dependence at the early stage of polymerization while the deviation ...     

STUDIES ON SEQUENCE STRUCTURE OF PET/PHB COPOLYESTERS

In this paper,the sequence distribution in the copolyester made from polyethyleneterephthalate (PET) and p-hydroxybenzoic acid (PHB) at 290℃has been investigated by 400MHz ~1H-NMR.It has been found that reference factor m of PET/PHB copo!yester linearly de-creases when PHB molar fraction increases.In addition,a series of sequence structure parameters,such as PET,PHB segment mean length,randomness,etc.are calculated from a probability modelby m,X_(PHB)%.This copolyester made at 290℃ is found to be nearer to that of completely randomcopolymer compared with that of the eopolyester made at 270℃,as in the case of the generalcopolycondensation.PHB-rich phase is formed only when PHB per number≥4,basing on thisconclusion,we establish the relationship between theoretical contents of PHB-rich phaseW_(PHB)% and PHB contents X_(PHB)% :W_(PHB)%=104.0X_(PHB)~(4.40) The minimum PHB-rich phase con-tent forming liquid crystal phase is 1.1% wt.     

HMLS纤维模量应变曲线的多项式模拟

对HMLS纤维应力应变曲线取得的关键数据点采用多项式模拟，应用误差理论检验其合理性，得到合理优化的应力应变曲线，经求导后，用MATLAB语言模拟出模量应变曲线。