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植物叶肉细胞的类角蛋白中间纤维   总被引:3,自引:0,他引:3  
本文根据中间纤维对非离子去垢剂与盐溶液处理高度稳定性的特点,应用选择性分级抽提技术结合整装电子显微镜制样技术,清楚地显示出在玉米与烟草的叶肉细胞内存在直径为10nm的类中间纤维构成的精细网络结构。继而用电子显微镜免疫胶体金技术进一步证实,这些类中间纤维的主要成分是类似动物细胞的角蛋白。从而首次证明植物叶肉细胞中也存在类似动物的角蛋白中间纤维体系。与此同时,在玉米与烟草的叶肉细胞内还可以观察到3nm的细纤维,它们与10nm中间纤维紧密连接。  相似文献   

3.
等离子体改性聚丙烯纤维表面的XPS研究   总被引:12,自引:0,他引:12  
用等离子体技术处理了聚丙烯纤维表面.用X-射线光电子能谱(XPS)研究了聚合物表面的元素组成、相对含量的变化、表面官能团的类型.采用曲线拟合分峰技术对谱图进行数学处理,结果表明:尽管处理气氛不同,聚丙烯纤维表面除含有C—H和C=C键外,还引入了O、N元素.形成活性基团:-OH、>C=O、-COOH、-NH2和-CONH2等,提高了聚合物表面活性。  相似文献   

4.
芳香族聚酰胺纤维改性技术进展   总被引:5,自引:0,他引:5  
分析了芳香族聚酰胺纤维目前存在的问题,在55篇参考文献的基础上,综述了间位芳香族聚酰胺、对位芳香族聚酰胺的各种改性技术的进展,探讨了芳香族聚酰胺纤维改性技术的发展前景.  相似文献   

5.
CuS表面改性聚丙烯腈纤维的结构及导电机理的研究   总被引:3,自引:0,他引:3  
研究了用一步反应法制备的CuS表面改性的聚丙烯腈导电纤维的微观结构、导电性和温度的变化规律及其导电机理,观察了CuS在纤维表面上的结晶态及晶型变化现象,证实了该导电纤维的以电子导电为主的导电机理。  相似文献   

6.
甲基磺酸对PBO纤维的表面改性   总被引:1,自引:0,他引:1  
采用甲基磺酸(MSA)溶液对PBO纤维表面进行化学改性,用单丝拔出试验测定了改性前后PBO纤维与环氧树脂基体的界面剪切强度,并通过扫描电镜(SEM)、X-射线光电子能谱(XPS)、接触角分别对处理前后纤维的表面形貌、表面组成以及表面自由能进行了表征.研究结果表明:在甲基磺酸质量分数为60%的溶液中,60℃下处理6 h的PBO纤维与环氧树脂基体的界面剪切强度比未处理的提高了81%,并且纤维表面O元素的质量分数增加了13.3%,表面自由能增加了17.3%.当溶液中甲基磺酸的质量分数、处理时间和处理温度进一步提高时,PBO纤维的皮层将遭受破坏,导致界面剪切强度下降.  相似文献   

7.
辉光放电等离子体对聚丙烯纤维的表面改性   总被引:11,自引:0,他引:11  
在对电晕、介质阻挡放电、γ射线辐射接枝对化纤改性的简要介绍基础上,重点论述了辉光放电等离子体对聚丙烯纤维的改性。并按等离子体技术的发展过程,对低压和常压辉光放电等离子体对聚丙烯纤维与织物改性的特点、原理及发展前景进行了扼要综述,指出常压辉光放电等离子体是一种很有潜力的表面改性技术。  相似文献   

8.
张勇  鄢勇气 《化学研究》2021,32(3):277-282
苎麻纤维是一种古老而极具中国特色的天然植物纤维,因其独特的形态结构和物理化学性能,在我国农业和世界纺织工业中占有重要的地位.苎麻纤维的化学改性可以改变纤维的结晶结构,提升纤维的理化性能,有利于纤维的加工处理,改善苎麻织物的服用性能.本文综述了苎麻纤维的主要化学改性方法及其在纺织工业应用的研究进展.  相似文献   

9.
以Ce~(4+)引发丙烯腈与罗布麻纤维接枝共聚反应,用红外光谱表征了接枝纤维的结构。并探讨了接枝纤维皂化物时汞离子的吸附性能。C_(AN)为1.2×10~(-1)mol/L、C_(Ce)~(4+)为10×10~(-3)mol/L时接枝率较高,该接枝共聚物经皂化后能有效地吸附汞离子,pH值在10~11时吸附率最高,达0.583mg Hg~(2+)/g。  相似文献   

10.
活性炭纤维经改性剂浸渍,水蒸气高温活化后,增大了其对水中多环芳烃的选择性和吸附量,提高了检出限。活性炭纤维活化的最佳条件:在45%磷酸中浸渍6 h,水蒸气中活化30 min,活化温度为500℃。与未改性炭纤维相比,改性后的炭纤维经固相微萃取技术与气相色谱联用测定16种多环芳烃(PAHs),检出限由0.5~50μg/L降至0.01~0.5μg/L,加标回收率由46%~112%增至74%~124%。方法的灵敏度和准确性得到明显的改善,提高了该技术的实际应用价值。  相似文献   

11.
The application of modulated temperature programming to thermomechanical analysis affords a method for measuring the ‘true’ thermal expansion coefficients of materials that deform irreversibly during normal TMA. This may arise from creep under the applied load or changes in dimensions due to relaxation of orientation. Acrylic fibres made with various degrees of orientation shrink to different extents on heating but all show the same ‘true’ thermal expansion coefficients using this approach. The application of modulated temperature programming to Dynamic Mechanical Analysis is also discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

12.
聚丙烯酰胺双向凝胶电泳法分析变色人发角蛋白组成   总被引:1,自引:0,他引:1  
报道了一种用双向聚丙烯酰胺凝胶电泳分析经S-羧甲基化修饰的变色人发角蛋白样品的方法,以含8mo1/L脲变性凝胶电泳做第一向,SDS-PAGE做第二向。不同处理的变色人发得到有差别的双向电泳图谱,即不同处理方法得到的人发蛋白质组成有差异。以此可做为人发变色处理的一个定性方法。  相似文献   

13.
The effect of AMP.PNP on the thermal stability and dynamics of myosin head were investigated by using DSC and different spin label technique for chemically skinned muscle fibres prepared from rabbit. The thermal unfolding of the fibres in rigor, strong as well as weak-binding state showed a complex process characterizing at least three discrete domain regions with different stability (T m =54, 58.4 and 62.3°C). The unfolding at 54°C refers to the catalytic domain of myosin, whereas transition at T m =58.4°C represents the rod-like region. In the presence of AMP.PNP only the parameters of the last transition changed significantly (T m =70.4°C) showing an increased interaction between actin and myosin heads being attached to actin. Measurements on MSL-fibres (labelled at Cys-707 of myosin) in the presence of AMP.PNP showed that about half of the cross-bridges dissociated from actin. This fraction had a dynamic disorder, the other population had the same spectral feature as in rigor. In contrast, on TCSL-fibres AMP.PNP increased the orientational disorder of myosin heads, a random population of spin labels was superimposed on the ADP-like spectrum showing conformational and motional changes in the internal structure of myosin heads. ST EPR measurements reported increased rotational mobility of spin labels in the presence of AMP.PNP. The DSC and EPR results suggest that in the presence of AMP.PNP the attached heads have the same global orientation as in rigor, but the internal structure undergoes a local conformational change. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
角蛋白系硬蛋白之一,广泛存在于动物的毛发及皮肤的衍生物中。目前,从毛发和羽毛中提取角蛋白常用的化学方法有酸碱水解法、还原法和氧化法等。作为天然生物分子,角蛋白具有优异的生物活性、生物相容性、生物降解性、良好的材料力学性能以及自然丰度等特性,在生物医学领域有很多潜在的应用。本文介绍了角蛋白的结构以及主要的提取方法,并展望了角蛋白的生物医学应用前景。  相似文献   

15.
Metal cations are valuable antimicrobial additives for controlling of bacteria growth on textile fibres. By means of multiple actions they are able to suppress the undesirable microbe action also during wound healing. Dry-wet shaping technology offers numerous opportunities for implementation of antimicrobial activities into textile structures (fibres, yarn, fabrics). The degree of load, insertion step as well as type of additive (Ag, Cu, Zn) presents a broad field of physical modification of dry-wet spun cellulose fibres. The investigation of antimicrobial activities of manufactured fibres and yarns exhibit bactericide or bacteriostatic effects against typical pathogenic germs. Ag contents higher than 30 ppm in fibres and 0.06 per cent in yarns as well as Cu contents higher than 100 ppm in fibres and about 0.5 per cent in yarns are fairly effective for a permanent antimicrobial effect. Fabrics based on the developed fibres and yarns could already been successfully commercialised by innovative small and medium sized enterprises (SME).  相似文献   

16.
耐高温改性环氧树脂粘接剂的制备及改性机理研究   总被引:10,自引:0,他引:10  
采用新型固化体系和端羧基丁腈橡作为环氧树脂的改性剂,制备了一种具有耐高温、高强度、韧性好等特点的环氧树脂粘接材料。同 时对改性机理及增韧机理进行了初步探讨。  相似文献   

17.
有机硅改性有机合成树脂的研究状况   总被引:1,自引:0,他引:1  
有机硅聚合物具有优异的耐候性、耐玷污性和耐高低温性,高度的疏水性,良好的透气性等被广泛应用.各种有机合成树脂有各自的优点和缺点,它们的缺点正好是有机硅聚合物的优点.将有机硅引入有机合成树脂,利用有机硅优点改进有机合成树脂的不足,使有机硅和有机合成树脂的性能更加完善,这对有机硅和有机合成树脂工业发展具有重大的意义.因此有机硅改性有机树脂是近年来研究的热点.本文简单综述了几种有机硅化学改性有机合成树脂的性能特点、制备方法及研究发展状况.  相似文献   

18.
丙烯酸酯类与亚麻纤维接枝共聚反应的研究   总被引:3,自引:0,他引:3  
Abou-Zeid等人曾报道以Fe(~2+)-H_2O_2体系引发丙烯腈等单体与黄麻纤维的接枝共聚反应,Misra等人报道了以S_2O_8_2-TU为引发体系,甲基丙烯酸甲酯与黄麻纤维的接枝共聚,最近,我们报道了以Ce(Ⅳ)引发甲基丙烯酸甲酯、丙烯酸乙酯(EA)分别与苧麻及亚麻纤维的接枝共聚。亚麻纤维与丙烯酸酯类单体接枝改性后,仲长率有所提高,加强了结合力,改善了成纱品质,因此引起人们的重视。本文以过硫酸钾-硫脲(KPS-TU)为引发体系,研究丙烯酸甲酯(MA)、EA及丙烯酸丁酯(BA)与亚麻纤维的接枝共聚反应规律,用IR、SEM、X射  相似文献   

19.
氮酮对鼠角质层角蛋白作用的光谱证据   总被引:2,自引:0,他引:2  
应用13CNMR和ATR-FTIR为测试手段,探讨角蛋白的分子运动自由度与堆积结构,以及氮酮对鼠角质层角蛋白的作用.经氮酮处理后,角蛋白主侧链碳的自旋晶格弛豫时间t1从7.9,8.2和2.1s分别减小到5.4,3.6和1.6s,表明氮酮作用加快了角蛋白所有碳的运动,获得了氮酮对鼠角质层角蛋白作用的确凿证据.同时,ATR-FTIR结果显示,经氮酮处理后,角蛋白的酰胺吸收峰带的峰位从1544.7cm-1向低波数位移到1541.4cm-1.结果表明氮酮可使部分角蛋白从α-螺旋型结构向β-折叠型结构和无规则卷曲型结构转变,导致角蛋白的堆积结构疏松,增大了角蛋白碳运动的自由度  相似文献   

20.
We report for the first time the stabilization of silver nanoparticles in good yield, average diameter 3.5 nm, using wool keratin hydrolysates as stabilizers. The nanoparticles are extremely stable as a suspension and can be lyophilized into a powder and easily reconstituted in solvent with no change in spectral properties relative to the initial suspension. The nanoparticles interact with nitrogen and oxygen moieties of the keratin hydrolysates under the pH conditions used in the synthesis and appear to act as cross-linkers between adjacent chains. The product has excellent handling properties which we believe will make it a very attractive biocompatible coating/additive, providing prolonged antimicrobial efficacy to a wide variety of products such as textiles, plastics, paints, orthopedic devices and others.  相似文献   

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