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1.
Surface of Ultra-high molecular weight polyethylene (UHMWPE) fiber were treated by chromic acid chemical etching, pyrrole chemical vapour phase deposition and the complex of these two methods, respectively. The change of surface properties and structure of fibers were discussed by Fiour Transform Infrared Spectroscope (FTIR), Dynamic Mechanical Analysis (DMA) and Scanning Electron Microscope (SEM). The results show that some new oxygenous groups could be found on surface of UHMWPE fiber after chromic acid chemical etching, which enhanced intemolecular interaction with polypyrrcle. The adhesion of the fiber and resin natrix increased after pyrrole chemical vapour deposition. When chromic acid etching combined with pyrrole chemical vapor deposition, the treated fiber not only has the same properties as original fiber bat also outstanding adhesion to epoxy resin matrix, and its composites have better mechanic properties shear strength), resulting from intemolecular interaction treated fiber and polypyrrole.  相似文献   
2.
Two aromatic polyimides were prepared by twostep way.Firstly,the poly (amic acid) s were synthesized from 1,3-bis(4-amiaophenoxy)benzene and two difierent aromatic dianhydrides.Secondly,polyimides were prepared via thermal imidization of poly(amic acid) precursors.The polyimides prepared were insoluble in cammon organic solvents such as tetrahydrofuran,chloroform and N,Ndimethylformamide.The inherent viscosities of poly(amic acid)s were 1.82 dL/g and 2.67 dL/g.The high inherent viscosities were due to the strong intra-or intermoleeular hydrogen interaction.The polyimides were characterized by mechanical and thermal analysis.It was found that the samples are of excellent thermal stability,higher glasstransition temperature and excellent dynamic mechanical andthermal properties.  相似文献   
3.
春秋时的赋诗、言语引诗 ,展现了诗、乐、舞、礼由合而分的演变过程。春秋时的赋诗 ,既反映出诗与礼、乐、舞的统一 ,同时也呈现了诗在演变中与礼、乐、舞的分离。春秋盛行的言语引诗是诗与礼、乐、舞走向分离的产物。这一演示过程呈现出中国早期诗歌的礼用本质。孔子的《诗》论 ,与春秋赋诗、言语引诗体现出的诗学观念是一致的 ,它较为全面地阐发了以礼为核心的《诗》的功能  相似文献   
4.
将以ATP6作为诱饵蛋白,应用酵母双杂交(Yeast Two Hybrid,Y2H)已筛选到的3′端含有终止密码子的一个片段,通过5′RACE获得该基因全长并,命名为Bn-Zn,其编码氨基酸序列中含有一个RINGv(RINGvariant)结构.通过构建该基因的真核正向表达载体pCAMBIA2301G-Bn-Zn,以农杆菌(Agrobacterium tumefaciens)介导转入细胞质雄性不育恢复系油菜8410018幼苗下胚轴,经过诱导愈伤和再分化,成功得到了转基因植株.  相似文献   
5.
本文介绍了商种纯相位锁定电路及其实验结果。这种锁定具有许多奇异的特性,有广泛的应用。  相似文献   
6.
Cooling function is definitely one of the most desirable attributes of clothing. In spite of the recent progress on phase changing material (PCM) research, the final products with sufficient amount of cooling capability have not yet to be developed in market. A new concept of cooling fabrics has been proposed by applying "Peltier effect" to textile materials. It occurs whenever electrical current flows through two dissimilar conductors t depending on the direction of current flow, the junction of the two conductors will either absorb or release heat. This effect has been tested on P-type and N-type conducting polymers. A P-type conductive polypyrrole coated fabric was synthesized by in- situ polymerization on plain weave PET to make conductive fabrics. And an N.typo electrically conductive material was synthesized by treatment of MWNT and polyethyleneimine (PEI). A noticeable amount of temperature difference has been found in the fabric.  相似文献   
7.
Fabrication of a Polyamide/Polysulfone Hollow Fiber Composite Membrane   总被引:1,自引:0,他引:1  
Introduction Appliedtomembraneseparationtechnology,components canbeseparatedmechanicallywhenasolutiongoesthrough asemipermeablemembrane.Themembranecanbesheet,spiralwound,tubeorhollowfiber,amongwhichhollow fiberisofthehighestspecificsurfaceandthusthemost effective.Thebestknownliquid phasemembraneprocessesare reverseosmosis(RO),ultrafiltration(UF),microfiltration(MF),dialysis,andelectrodialysis(ED).However,over thepastfewyears,anewmembraneprocesscalled nanofiltration(NF)hasemergedthatpromise…  相似文献   
8.
详细研究了具有限时滞van der pol方程在经历Hopf分支时,小周期扰动对系统的影响,特别讨论了扰动频率与Hopf分支固有频率在次调和共振的情形,表明了在某些参数区域内,系统存在次调和分支,并且讨论了其分支解的稳定性.  相似文献   
9.
给出了闭值域定理在局部凸空间中的推广  相似文献   
10.
湖南省大气污染特征与防治研究   总被引:7,自引:0,他引:7  
根据近两年《环境保护报》每周一次的湖南省主要城市空气质量周报资料,采用综合污染指数法,统计分析出湖南省13个主要城市空气质量总体较好,在Ⅱ级标准以内,TSP为首要污染物,SO2为第二污染物,NOx污染轻微,且冬季污染高于夏季;同时大气环境质量与城市工业化水平和以煤为主的能源结构密切相关,并具有区域性和季节性的差异。长沙、株洲、湘潭和娄底污染严重,趋于Ⅲ级标准,永州、张家界空气质量较优,接近Ⅰ级标准,其它城市居中。在分析湖南省大气污染原因和特征的基础上,提出调整能源结构,加强污染治理以及城市绿化等措施,以提高城市大气环境质量,保证经济可持续发展。  相似文献   
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