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以3,5-二羟基苯甲醇和4-羟基-4’-硝基偶氮苯为原料合成一种新的含氨基的偶氮中间体,然后与1,6,7,12-四(4-叔丁基苯氧基)-3,4,9,10-苝四甲酸二酐缩合得到新型偶氮-苝酰亚胺二元染料(AZO-PTCDI)。采用紫外可见-吸收光谱和荧光光谱研究UV光照时间和浓度等因素对AZO-PTCDI光响应行为的影响。研究结果表明:AZO-PTCDI的浓度越大,偶氮基团在353 nm处的特征吸收峰强度随UV光照时间的延长而下降越缓慢,表明偶氮生色团由反式结构向顺式结构的转变速度越慢;对于相转移法组装形成的AZO-PTCDI聚集体结构,两相溶剂甲醇与三氯甲烷的体积比越大,越容易组装形成较规整的类纤维状结构;将未光照和UV光照后的AZO-PTCDI三氯甲烷溶液快速扩散到甲醇中所得到的聚集体形貌结构存在明显差异,前者表现为短的一维结构,后者为不规则的类球状结构,表明光照驱动偶氮基团的反式结构向顺式结构的转变导致苝酰亚胺的N-取代基的几何空间构型发生改变,削弱了分子间的π-π作用和烷基链的疏水作用力,致使聚集体分子排列无序化。 相似文献
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随着我国经济的不断进步,工业发展十分迅速,工业企业的发展速度有了很大的提高,为了适应现代化的社会生产,工业企业内部进行着不断地创新,随着电气自动化的控制技术引进,工厂的生产效率得到了大幅度的提高,目前,这项技术在工厂内部备受青睐,得到了最广泛的应用,并逐渐在工厂普及。在工厂生产和发展中,电气化自动控制技术是一项十分重要的技术,本文对工厂中的电气自动化控制技术进行分析,希望可以为这项技术在工业生产中的创新和实施提供帮助。 相似文献
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在氢化物发生和火焰原子吸收分光光度法中使用的同心双毛细管喷雾器被应用于测定头发、食盐,醋和鱼露中的铅含量.让一根毛细管吸喷1%KBH4溶液,另一根吸喷含有1%K3[Fe(CN)6]和 0.3mol·L-1HNO3的铅溶液.用装有微分放大器的简易型火焰原子吸收分光光度计测量在空气-乙炔焰中产生的原子吸收信号.使方法的灵敏度明显提高.所建立的标准曲线的线性范围为0.016-0.56ppmPb.当8次测定0.032ppmPb时,相对标准偏差小于4%. 相似文献
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The random amplified polymorphic DNA analysis was used to estimate genetic diversity in one successively cultivated stock and three wild stocks of Penaeus chinensis shrimp, two of which were collected from the spawning and wintering grounds in the west coast of Korean Peninsula, and one from the feeding ground in the China coast of the Yellow Sea. A random primer kit was employed to scan the genomic DNA in 20 individuals of each index stock. A total of 110 reproducible RAPD markers were obtained, 68.2 % of which showed a sound eonformability within all the individuals detected, implying that the genetic variability in P. chinensis is relatively low. The proportions of polymorphic loci among these four stocks ranged from 20% to 33.3%, while the degrees of genetic polymorphisms varied from 0.0093 to 0.0307. The genetic variability of inter-stocks was higher than that of intra-stock. The genetic diversity in different stocks differed from each other; that is, a less genetic differentiation in the spawning and wintering stocks from the west coast of Korean Peninsula was revealed and their genetic diversities were higher than that of the spawning stock in the Bohai Sea and the China coast of the Yellow Sea. As detected, the genetic diversity in the successively cultivated stock was the lowest among these four stocks. Through genetic distance analysis between a random pair of individuals, a dendrogram of the above-mentioned four stocks was constructed by unweighted pair group method with arithmetic mean. The results based on cluster analysis well fitted with the geographical distribution of P. chinensis in the Bohai and Yellow Seas. 相似文献
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中国对虾遗传多样性的RAPD分析 总被引:19,自引:0,他引:19
采用随机扩增多态DNA技术,对中国对虾的3个野生地理群体--朝鲜半岛西海岸产卵群体及其越冬群体、黄渤海中国沿岸群体和一个人工累代养殖群体进行了遗传多样性研究.用一组随机引物,对每个群体各20尾对虾的基因组DNA进行扩增,共获得110个重复性好且谱带清晰的RAPD标记,68.2%的标记在所有个体间保持稳定的一致性,表明中国对虾的遗传多样性水平偏低.4个群体的多态位点比例在20%~33.3%之间,群体内的遗传多态度为0.0093~0.0307.群体间遗传变异高于群体内.不同群体间遗传变异水平不同,朝鲜半岛西海岸产卵群体及其越冬群体相近且高于黄渤海沿岸群体,累代养殖群体遗传变异度最低.通过成对的遗传距离分析,用非加权的组平均法构建了上述4个群体中国对虾的谱系关系图,该聚类分析的结果与中国对虾在黄渤海的地理分布相吻合. 相似文献
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