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191.
用ATRP法构筑核壳型梯度极性的多羟基多臂星状超支化聚合物及聚合物刷——双层聚合物刷的合成与表征 总被引:3,自引:0,他引:3
设计并通过原子转移自由基聚合方法 (ATRP)合成了核壳型多羟基多臂星状超支化聚合物刷 .以 2 溴异丁基酰溴封端的超支化聚 (3 乙基 3 羟甲基氧杂环丁烷 ) (HP Br)作为大分子引发剂 ,采用Cu(I)Br和N ,N ,N′ ,N′ ,N″ 五甲基二乙基三胺 (PMDETA)催化体系 ,在丁酮与丙醇的混和溶液中 ,通过甲基丙烯酸羟乙酯(HEMA)的ATRP溶液聚合 ,得到了一系列含有大量羟基的多臂星状超支化聚合物刷 (HP g PHEMA) ,并考察了其羟基的活性 ,发现羟基还可以与苯甲酰氯发生反应 .产物的结构和热性能用1 H NMR、FTIR、GPC、TGA、DSC等进行了表征和测试 . 相似文献
192.
Fabrication of hexaphenylsilole nanowires and their morphology-tunable photoluminescence. 总被引:1,自引:0,他引:1
Liping Heng Jin Zhai Anjun Qin Yuqi Zhang Yongqiang Dong Ben Zhong Tang Lei Jiang 《Chemphyschem》2007,8(10):1513-1518
Immersion of nanoporous alumina membranes into saturated solutions of hexaphenylsilole with subsequent solvent evaporation affords aligned organic nanowires. The luminescent properties of the hexaphenylsilole nanowires can be manipulated by varying their morphologies, which were controlled by changing the channel sizes of the alumina templates. 相似文献
193.
A simply fabricated microfluidic device using a green organic light emitting diode (OLED) and thin film interference filter as integrated excitation source is presented and applied to fluorescence detection of proteins. A layer-by-layer compact system consisting of glass/PDMS microchip, pinhole, excitation filter and OLED is designed and equipped with a coaxial optical fiber and for fluorescence detection a 300 microm thick excitation filter is employed for eliminating nearly 80% of the unwanted light emitted by OLEDs which has overlaped with the fluorescence spectrum of the dyes. The distance between OLED illuminant and microchannels is limited to approximately 1 mm for sensitive detection. The achieved fluorescence signal of 300 microM Rhodamine 6G is about 13 times as high as that without the excitation filter and 3.5 times the result of a perpendicular detection structure. This system has been used for fluorescence detection of Rhodamine 6G, Alexa 532 and BSA conjugates in 4% linear polyacrymide (LPA) buffer (in 1 x TBE, pH 8.3) and 1.4 fmol and 35 fmol mass detection limits at 0.7 nl injection volume for Alexa and Rhodamine dye have been obtained, respectively. 相似文献
194.
Zhengping Hao Lidun An Junling Zhou Hongli Wang 《Reaction Kinetics and Catalysis Letters》1996,59(2):295-300
Supported gold catalyst for eliminating hydrogen from CO2 feed gas in the production of urea is found to be superior to other industrial catalysts (e.g. Pt/Al2O3 and PdPt/Al2O3) in catalytic activity and resistance to sulfur poisoning. 相似文献
195.
196.
1 INTRODUCTION The infinite networks constructed from transition metal complexes have attracted considerable current interest in recent years. The motivation behind this activity has been stimulated by their potential appli- cations in selective inclusion of ions, molecular re- cognition, host-guest chemistry, ion exchange, cata- lysis, electrical conductivity, magnetism, optics and so on[1~4]. It is well known that the diversity in structures and topologies of supramolecules is attri- b… 相似文献
197.
Lei JD Tong AJ 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(6):1029-1033
An integrated microchip was presented for selective recognition of Z-L-Phe-OH-NBD, using molecular imprinting technique. Molecularly imprinted polymer (MIP) were prepared by copolymerization in the presence of template molecule Z-L-Phe-OH-NBD, in which methacrylic acid and 4-vinylpyridine were used as functional monomers and ethylene dimethacrylate used as crosslinker. Imprinted polymer particles were introduced into a microchannel fabricated with a new material i.e. poly(methylvinylsiloxane) by simply rapid prototyping method. Imprinted effects were evaluated by laser-induced fluorescence (LIF) detection where the results indicated that good selective recognition for Z-L-Phe-OH-NBD in the imprinted polymer was obtained; the adsorption percentage of Z-L-Phe-OH-NBD was 61%. In contrast to conventional molecular imprinting analysis, integration shortened overall analysis time from 4h to 10 min. 相似文献
198.
199.
ICP激发光源以其独特的功能使ICP/AES技术在稀土分析中的应用日益广泛,在一定程度上取代了经典的直流电弧光谱法,但应指出,由于常规雾化器的低雾化效率(≤5%)和试样的高倍稀释,ICP/AES技术的实际检测能力的改善并不明显,本文用ICP光谱法测定了 相似文献
200.