The Oppo BDP-203 is an excellent high-end 4K Blu-ray disc player, but image quality improvements over cheaper players are tough to spot. Read full review Autoplay: ON Autoplay: OFF
Efflorescence is the stubborn problem that has caused confusion and trouble for masonry since the first time it appeared thousands of years ago on ancient masonry walls. Efflorescence is normally the white, powdery scum that can appear on masonry walls after construction but can also be brown green or yellow, depending on the type of salts.
When a volume of gas is opened to another volume with less pressure, the gas can either diffuse or effuse into the container. The main difference between diffusion and effusion is the barrier between the two volumes. Effusion occurs when there is a barrier with one or many small holes that prevent the gas to expand into the new volume unless a gas molecule happens to travel through the hole.