Nanotextured Surface Dramatically Improve Solar Cell Efficiency. The Engineer posted on January 22, 2015 | | 4074 views. Reducing the amount of sunlight that bounces off the surface of solar cells helps maximize the conversion of the sun's rays to electricity, so manufacturers use coatings to cut down on reflections.
The main entry door must conform to IRC specifications. Exterior doors often are the most visible parts of a house and like interior doors, are available in standard sizes. They range in width from 2 feet to more than 3 feet, and in height from 6 feet, 8 inches to more than 8 feet. Standard thickness is 1 3/4 inches.
Solid wood doors. The standard exterior door material, solid wood, is still the most popular. It may be flush, paneled, and with or without glass. The most common materials for solid wood doors are oak, fir, and pine, along with cherry, walnut, mahogany, and maple. The standard entry door is 3 feet wide and 6 feet 8 inches tall.