The crystallization mechanism of zeolites remains unclarified to date because of lack of effective techniques in characterizing the local structures of amorphous precursors under synthetic conditions. Herein, in situ high-energy X-ray total scattering measurement with pair distribution function analysis is performed throughout the hydrothermal synthesis of SSZ-13 zeolite to investigate the amorphous-to-crystalline transformation at the sub-nano level in real time. Ordered four-membered rings (4Rs) are dominantly formed during the induction period, prior to the significant increase in the number of symmetric six-and eightmembered rings (6Rs and 8Rs) in the crystal growth stage. These preformed ordered 4Rs contribute to the formation of d6r and cha composite building units containing 6Rs and 8Rs with the assistance of the organic structure-directing agent, leading to the construction of embryonic zeolite crystallites, which facilitate the crystal growth through a particle attachment pathway. This work enriches the toolbox for better understanding the crystallization pathway of zeolites.

CON-type zeolites have great potential as highly propene-selective catalysts in methanol-to-olefins reactions; however, their insufficient lifetime is a major limitation. This study demonstrates the remarkably prolonged lifetime of CON-type zeolite...

This paper summarizes the results of an investigation on the viewing angle requirements for large flat-panel television displaysas well as on screen tilting as a means of reducing glare in accordance with the "Ergonomic Design Guidelines for Flat Panel Display Televisions" established by a special committee of the Japan Ergonomics Society. First, taking into account screen size, we investigated viewing angle requirements through a field survey of household television viewing conditions. We then evaluated the influence of the size, mounting height, and tilt of the screen on the occurrence of glare. Next, we conducted laboratory experiments to investigate the allowable tilt angle for ensuring acceptable viewing comfort and the optimum screen tilt angle for each mounting height. The results can be used as guidelines for adjusting viewing conditions as well as for ergonomic design of flat-panel television displays.

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