Synthesis and spectroscopic characterization of binaphthol aminosugars for stimulation of DNA strand slippage synthesis

Expansion of DNA repeat sequences is associated with many human genetic diseases. Bulged DNA structures have been implicated as intermediates in DNA slippage within the DNA repeat regions. Two new binaphthol aminosugars were first synthesized as DNA bulge binders to study the triplet repeat expansion due to the wedge-shaped structure of 1,1′-bi-2-naphthol. Both compounds were structurally characterized by 1- and 2-D NMR. They showed remarkable fluorescence enhancement when binding with bulge DNA and they exhibited stimulation for ATT·AAT trinucleotide repeat DNA sequence slippage synthesis.     

Novel techniques of PDLC film preparation furnishing manifold properties in a single device

Three novel techniques of polymer dispersed liquid crystal (PDLC) film preparation have been proposed to obtain/induce systematically varying manifold properties in a single device. These three techniques were used to prepare ‘wedge-shaped’, ‘multi-channelled’ and ‘grating type’ PDLC films. Arrangement and configuration of liquid crystal (LC) microstructures inside these PDLC films, which were conveniently divided into different zones, have been investigated using a polarising optical microscope (POM) and scanning electron microscope (SEM). POM images indicate a predominant bipolar structure in all zones of different types of PDLC films but with varying size and density. Further, the electro-optical (EO) properties of PDLC films for different zones have different morphological characteristics as indicated (observed) in POM and SEM images and were dependent on LC droplet shape, size and distribution. Also different zones show different absorbance/transmittance characteristics in the visible range. Thus, our study proposes a single device with manifold properties. Also, the desired properties can be obtained by selecting the suitable zone from the PDLC composite film.     

Buckle morphologies of wedge-shaped Fe films quenched by silicone oil during deposition

A characteristic wedge-shaped iron (Fe) film system, deposited on glass substrates by a DC-magnetron sputtering method and quenched by silicone oil during deposition, has been successfully fabricated. Telephone cord buckles induced by residual compressive stress can be widely observed in the samples. They are shown to nucleate and grow slowly in the atmosphere, but propagate rapidly after disturbance of the film by an external force. Various buckling phenomena, such as generation of disordered telephone cord networks on a isotropic substrate, formation of parallel wavy buckle and circular blister lines on a patterned substrate, partial healing of buckling by pushing the film back to the substrate during the propagation process, occurrence of straight-sided blisters near a step edge, are present in this paper.     

Fabrication of 3D inverse opal structured photonic crystal by using wedge-shaped cell method

A simple and low cost fabrication method for three dimensional inverse opal structured photonic crystal by using wedge-shaped cell (WSC) was suggested and demonstrated. The key idea of our method in the infiltration process was that the opal template was attached on the upper plate of the WSC, by which we could prevent the surface sedimentation of suspension. The micro shape and the transmission spectrum of the fabricated inverse opal structured photonic crystal were measured and discussed.     

高功率楔形介质填充天线设计

 针对高功率超宽带天线应用中的绝缘性及方向性等关键问题,设计了一种基于TEM喇叭天线形式的楔形介质填充天线,并利用时域有限差分数值方法分析了这种新型介质填充天线的辐射性能。数值模拟与测试结果表明,所设计的这种楔形介质填充天线不仅可以满足高功率天线的绝缘性要求,而且在主轴方向上具有较强的辐射场。