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Comment Re:Concrete composition (Score 1) 76

Silicates, sulfates, aluminates, etc. Look up "Portland cement". The Portlandite that they're talking about is only a very small part. The cement-making process requires very high temperatures to create the calcium silicates and such that are actually hard. Limestone is not hard enough or strong enough for heavy construction. Pretty white facings, yes. Structural strength, no.

Comment Re:Donald Trump is above the Law (Score 2) 690

Too bad they don't teach American History in school any more.

The Electoral College was a compromise among those drafting the Constitution to provide more equal representation to the (very) small (sovereign) states, such as Rhode Island, to keep them from being totally overshadowed by the larger, more populous states such as New York or Virginia or Pennsylvania. Without this compromise, there would have been no acceptance of the Constitution, and hence, no Union. Remember, they were piecing together the United States from thirteen individual sovereign states, each with its own separate government.

Travel time had nothing to do with it, although it did provide that benefit. By the time anybody was coming from the Ohio Valley, the EC was a well established fact.

Comment Re:Arbitrary definitions (Score 1) 355

The entire timekeeping system for the world is based on the definition of 12:00:00 GMT (aka Zulu, aka UTC) as the time when the sun is directly overhead at the Greenwich Observatory in Greenwich, England. Hence Greenwich Mean Time. Arbitrary? Perhaps. But recognized by every standards body on the planet. History, my friend.

Comment Re:That makes zero sense (Score 5, Informative) 169

Anything beyond about 20 feet is essentially at infinity focus. What is lacking in cameras is depth perception. Try driving, or backing up, with one eye covered (caution). It's surprisingly difficult to do confidently. Until they figure out how to do 3D cameras and displays in cars, they won't replace mirrors in functionality.

Comment Depth perception? (Score 1) 290

Are these rear view cameras going to be 3D? Has anyone even considered the disadvantage of losing any depth perception to the flat, 2 dimensional presentation of a video screen? I have trouble imagining the difficulty this would present in a backing situation. With a mirror, you can get a sense of depth and perspective to judge distances. A camera would just give a flat, detached representation of what was there. And perspective would be dependent on the focal length of the lens, among other things.

Comment Re:I'd try... (Score 1) 512

Use a moderate amount of rubbing alcohol to help get the water out AFTER you flush with copious amounts of deionized (as opposed to distilled) water. As a chemist, I have cleaned up sensitive electronics that have had potentially corrosive vapors condense on them by washing thoroughly with high purity water. The important thing is to remove the ions that will be in the dirty water. Then, yes, try to remove the clean water as much as possible in a reasonable time. Rubbing alcohol will kill the surface tension of the water, along with the mold, and help the droplets of water flow out. Unfortunately, all available rubbing alcohol contains a large amount of water, so you will still have to wait until that evaporates. But deionized water should not cause any further damage to the electronics. But make sure the label of the water bottle indicates deionization - distilled water can actually still contain a fair amount of ionic material because it is done so poorly. But some "Distilled Water" will indicate "purified by deionization" in the fine print.

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