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11.
A new method is described for the electroless deposition of copper onto glass.Commercially available glass slide was modified with γ-aminopropyltrimethoxysilane to form self-assembled monolayer (SAM) on it .Then it was dipped directly into PdCl2 solution instead of the conventional SnCl2 sensitization followed by PdCl2 activation.Experimental results showed that the Pd^2 ions from PdCl2 solution were coordinated to the amino groups on the glass surface resulting in the formation of N-Pd complex.In an electroless copper bath containin a formaldehyde reducing agent,the N-Pd complexes were reduced to Pd^0 atoms,which then acted as catalysts and initiated the deposition of copper metal.Although the copper deposition rate on SAM-modified glass was slow at the beginning,it reached to that of conventional method in about 5min.  相似文献   
12.
Based on the standard phosphoramidites chemistry protocol, two oligonucleotides synthetic routes were studied by contact stamping reactants to a modified glass slide. Route A was a contact coupling reaction, in which a nucleoside monomer was transferred and coupled to reactive groups (OH) on a substrate by spreading the nucleoside activated with tetrazole on a polydimethylsiloxane (PDMS) stamp. Route B was a contact detritylation, in which one nucleoside was fixed on the desired synthesis regions where dimethoxytrityl (DMT) protecting groups on the 5'-hydroxyl of the support-bound nucleoside were removed by stamping trichloroacetic acid (TCA) distributed on features on a PDMS stamp. Experiments showed that the synthetic yield and the reaction speed of route A were higher than those of route B. It was shown that 20 mer oligonucleo-tide arrays immobilized on the glass slide were successfully synthesized using the PDMS stamps, and the coupling efficiency showed no difference between the PDMS stamping and the co  相似文献   
13.
研究了分子印章法DNA芯片在片合成技术中的压印化学合成过程,提出了压印偶联反应和压印脱二对甲氧基三苯基阳离子(DMT)反应合成寡核苷酸的2种方案,并对其合成产率的差异进行了比较.由于单次压印偶联反应比压印脱DMT反应合成效率高且所需时间短,故选择压印偶联反应来合成寡核苷酸及其阵列并对其工艺进行了优化.实验表明压印偶联反应的合成效率高,从第6个核苷开始偶联效率接近100%;压印 2次比压印 1次的偶联效率高且更均匀;压印 3次及3次以上除更均匀外对偶联效率的改善不明显;玻璃载片经多次压印后对偶联反应的影响不大.用压印偶联反应的方法成功合成出 20 mer的寡核苷酸探针.  相似文献   
14.
根据高光谱遥感图像的特点及二维Gabor滤波器纹理分割的原理,提出了一种基于三维Gabor滤波器的高光谱遥感图像分类方法。三维Gabor滤波器能够对高光谱遥感图像所有波段同时进行滤波,将大量的图像信息抽取为少量的不同尺寸、方向和波谱的响应,极大减少了高光谱遥感图像纹理信息提取的计算量。利用不同方向和尺寸的三维Gabor滤波器对祁连山黑河流域上游地区的Hyperion影像全波段进行滤波处理,获取26个纹理响应特征,并分析不同纹理对不同地物的区分度。利用自动子空间划分的波段指数(BI)进行波段选择,选取不同的波段组合进行试验,寻找最佳降维幅度。按照纹理对不同地物响应的区分度逐一加入三维Gabor纹理特征,利用三维Gabor纹理辅助光谱信息,运用支持向量机(SVM)的方法进行监督分类。结果表明,基于三维Gabor纹理和自动子空间BI波段选择的SVM分类方法能够在有效降低光谱维数的同时,提高高光谱遥感图像分类的精度和效率。  相似文献   
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