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1.
液晶显示器用导电粉的形状、尺寸及偏差对于液晶显示屏的质量控制来说是非常重要的。论述了液晶显示器(LCD)用导电粉的作用和性能要求。给出了液晶显示器用导电粉的扫描电镜图像。该图像对观测导电粉的粒径分布、导电粉在导电点中的浓度和分析导电点缺陷、提高液晶显示器的产品质量具有一定的意义。 相似文献
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从等离子体平板显示器(PDP)的发光原理出发,分析和研究了存贮控制电路的工作原理,提出基于FPGA的电路设计方案,并给出数据整理电路和驱动信号产生电路的具体电路框图,最后给出部分仿真波形. 相似文献
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Jerman S Podgornik A Cankar K Cadet N Skrt M Zel J Raspor P 《Journal of chromatography. A》2005,1065(1):107-113
The availability of sufficient quantities of DNA of adequate quality is crucial in polymerase chain reaction (PCR)-based methods for genetically modified food detection. In this work, the suitability of anion-exchange CIM (Convective Interaction Media; BIA Separations, Ljubljana, Slovenia) monolithic columns for isolation of DNA from food was studied. Maize and its derivates corn meal and thermally pretreated corn meal were chosen as model food. Two commercially available CIM disk columns were tested: DEAE (diethylaminoethyl) and QA (quaternary amine). Preliminary separations were performed with standard solution of salmon DNA at different pH values and different NaCl concentrations in mobile phase. DEAE groups and pH 8 were chosen for further isolations of DNA from a complex matrix-food extract. The quality and quantity of isolated DNA were tested on agarose gel electrophoresis, with UV-scanning spectrophotometry, and by amplification with real-time PCR. DNA isolated in this way was of suitable quality for further PCR analyses. The described method is also applicable for DNA isolation from processed foods with decreased DNA content. Furthermore, it is more effective and less time-consuming in comparison with the existing proposed methods for isolation of DNA from plant-derived foods. 相似文献
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液晶电视由于其优异的显示性能将会越来越受到青睐。本文简要综述了近年来电视用液晶材料的研究进展,归纳总结了这些液晶材料的合成方法及其热性能、介电各向异性、双折射率、粘度等特性。 相似文献
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The disadvantages of Normally White Twisted Nematic Liquid Crystal Display (NW-TN-LCD) were discussed. The reason that the negative birefringent polyimide thin filmswere used to compensate NW-TN-LCD to decrease off-axis leakage, improve contrast ratiosand enlarge viewing angles was explained in this paper. A certain polyimide thin film wastaken as an example to show compensation effect on NW-TN-LCD. 相似文献
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Affinity Chromatography of Insulin with a Heptapeptide Ligand Selected from Phage Display Library 总被引:1,自引:0,他引:1
A heptapeptide phage display library was screened with insulin to find its ligands for affinity chromatography. The peptide was synthesized and coupled to EAH Sepharose 4B (5.4 mol mL–1 bed). Then, insulin chromatography was carried out with mobile phases of different pH values and by the addition of urea and ethylene glycol. It was found that electrostatic interactions were predominant for the affinity binding, and hydrogen bonding might also contribute somewhat to the affinity. Finally, frontal analysis was performed and the dynamic binding capacity of the affinity column for insulin at 50% breakthrough was estimated at 60.6 mg mL–1 bed, which was about two times higher than the theoretical binding capacity of the monomeric insulin. The result suggests that insulin was bound in dimer state in a stoichiometric relationship with the coupled peptide, indicating the high binding efficiency of the peptide ligand for insulin. 相似文献
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