Synthesis of Silicate Zeolite Analogues Using Organic Sulfonium Compounds as Structure‐Directing Agents

A microporous crystalline silica zeolite of the MEL structure type and three other zeolite analogues composed of germanosilicate frameworks were synthesized using tributylsulfonium, triphenylsulfonium, or tri(para‐tolyl)sulfonium as the structure‐directing agent. The germanosilicates thus obtained had ISV, ITT, or a new zeolite structure depending on the synthesis conditions. The structure of the new germanosilicate was solved using X‐ray powder diffraction data with the aid of a charge‐flipping method. The solution indicated a crystal structure belonging to the P63/mmc space group with cell parameters of a=16.2003 Å and c=21.8579 Å. After calcination, the new germanosilicate material exhibited two types of accessible micropores with diameters of 0.61 and 0.78 nm.     

Polymeric photoacid generators for direct photochemical modification of surface

To achieve easy spin coating and enhanced efficiency in the photolithographic process for the direct photochemical modification of surface, we incorporated photoacid generator (PAG) into polymer backbone. Bis‐(4‐hydroxy‐phenyl)‐(4‐methoxy‐3,5‐dimethyl‐phenyl)‐sulfonium chloride was synthesized as a monomer, and was polymerized with sebacoyl chloride and terephthaloyl chloride. The resulting polymeric PAG in chloride salt form was converted to the p‐toluenesulfonate and 1‐naphthol‐5‐sulfonate forms with ion‐exchange reactions. By the photolithographic process with the polymeric PAG, the protecting groups of the linker molecules self‐assembled onto a glass plate were micropatterned to produce an amine pattern for the microarray of oligonucleotides. The acids generated from the polymeric PAG effectively deprotect the acid‐labile protecting groups of the linker molecules through a chemical amplification process in the exposed region. After the treatment of the patterned amino groups with a fluorescent dye, the pattern profiles were observed with a fluorescence scanner. The fluorescence image reveals a well‐defined pattern at a micro level, which clearly indicates that the polymeric PAGs have a great potential in photochemical surface modification for the microarray of oligonucleotides. Copyright © 2007 John Wiley & Sons, Ltd.     

Measuring efficiency of positive and negative ionic wind devices for comparison to fans and blowers

Many industries are pursuing alternate air moving devices to reduce the power consumption of their air cooled products. The literature suggests that ionic AMDs have low efficiency. The literature, however, does not define efficiency the same way the computer industry defines it for rotary AMDs. In this study, static efficiency of ionic AMDs was evaluated similar to rotary AMDs. Various emitter to collector distances and various ring lengths, were evaluated for positive and negative coronas. By controlling emitter to collector distance and collector length, efficiencies were obtained more reasonably compared to rotary devices.     

Effect of chemical structure of acrylic pressure‐sensitive adhesives for polarizing film on light leakage phenomenon in TFT‐LCDs

Increasing image quality in thin‐film transistor liquid crystal displays (TFT‐LCD) is a recognized challenge for electronic companies and specialists working in this area. One of the main problems in TFT‐LCDs is a phenomenon called “light leakage”, affecting black–white contrast and color brightness. It occurs because of a heat‐induced shrinkage and disorientation of the polarizing film of TFT‐LCD, which controls the intensity of the light from the backlight unit. Improvement of the light leakage can be achieved through using a pressure‐sensitive adhesive (PSA) used for assembling the polarizing film onto the TFT‐LCD panel. In this paper, eight acrylic/methacrylic monomers with high glass transition temperature (Tg) were employed for synthesis of the polymers for the adhesive. Effect of structure, Tg, and elasticity modulus of the synthesized polymers on the light leakage was investigated simultaneously for 2.5‐ and 7.0‐in. size samples. We demonstrated that the light leakage can be minimized through two different mechanisms—high stress relaxation of the polymers with low Tg and low modulus and high shrinkage resistance of the polymers with high Tg and high modulus. The results of this work indicate a possibility to develop a universal PSA for polarizing film in TFT‐LCDs of different sizes that will have a positive effect on manufacturing productivity and lowering prices of digital devices. Copyright © 2011 John Wiley & Sons, Ltd.     

Simultaneous control of haze and transmittance using a dye-doped cholesteric liquid crystal cell

We propose a light shutter device using dye-doped cholesteric liquid crystals for a high-visibility see-through display. In the focal-conic state, the proposed device can perfectly block the background image through simultaneous use of light scattering and absorption effects in a single-layered structure. By switching the proposed device placed at the backside of a see-through display, we can choose transparent or high-visibility display modes in a see-through display.     

On rings in which every maximal one-sided ideal contains a maximal ideal

Given a ring R, consider the condition: (^*) every maximal right ideal of R contains a maximal ideal of R. We show that, for a ring R and 0 ≠ e ² = e ∈ R such that ele ? eRe every proper ideal I of R R satisfies (^*) if and only if eRe satisfies (^*). Hence with the help of some other results, (^*) is a Morita invariant property. For a simple ring R R[x] satisfies (^*) if and only if R[x] is not right primitive. By this result, if R is a division ring and R[x] satisfies (^*), then the Jacobson conjecture holds. We also show that for a finite centralizing extension S of a ring R R satisfies (^*) if and only if S satisfies (^*).