I don't think even if the Library of Congress digitized and put online every book with an expired copyright, or even somehow every book in their collection that they would render the public library obsolete to 50-70% of the public. As long as we are only talking about books with expired copyrights, I can't see how this would render the public library obsolete to any of the public. My wife is a public librarian, one of her jobs is to periodically weed out books. Due to the limited shelf space, buying new books implies discarding a similar number of older books. By the time the copyright expires, many of the books are no longer in your library (but probably obtainable by interlibrary loan) That said, I can see the reason for digitizing some of the other (unique)source material first. What I objected to was not wanting to digitze the books at all.
Another benefit is increased life for a given battery size - the heat pipe is a passive device, and allows you to eliminate the cpu fan that would otherwise be required. Heat pipes are very simple, and very reliable. The ones used in laptop are a sealed copper tube containing a wick and a small amount of water. Heat vaporizes some of the liquid, which travels to the other end of the tube, where it condenses. Capillary forces return the liquid water - no outside power (or pump) required. They're probably a lot more reliable than the rest of the laptop - some have been operated continuously for 20 years.
One wonders if the cooling unit mentioned is really a heat pipe. The problem with this is that a heat pipe needs to have a gravity assist to work correctly No, many heat pipes contain a wick that returns the condensed liquid to the CPU by capillary action. Some of the heat pipes can operate with the laptop in any orientation. Maximum adverse elevation for heat pipe technology with water is on the order of 10 meters.
Its pure water, heat pipes can stand being frozen. Alcohol is not added, you would start distilling the alcohol, and end up with a poorly perfoming heat pipe. Distilled water is used because the system is operating a pressure less than atmospheric, and is sensitive to non-condensible gases. For example, copper is used with water in heat pipes, but aluminum is not - the water reacts with the aluminum to form small amounts of alumina, releasing hydrogen - this can impair heat pipe performance.
Actually invented by Gaugler (General Motors) in 1942. Reinvented at Los Alamos in the 60's for cooling thermionic devices (sort of a vacuum tube run "backwards" to generate electricity from heat). I'm somewhat surprised that this came up now. Water heat pipes have been used to cool chips in laptops for 4 to 5 years now. They basically spread out the high heat flux at the cpu to a lower heat flux, that can be more easily dissipated. Big advantage is longer battery life, since you don't need a fan
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I don't think even if the Library of Congress digitized and put online every book with an expired copyright, or even somehow every book in their collection that they would render the public library obsolete to 50-70% of the public. As long as we are only talking about books with expired copyrights, I can't see how this would render the public library obsolete to any of the public. My wife is a public librarian, one of her jobs is to periodically weed out books. Due to the limited shelf space, buying new books implies discarding a similar number of older books. By the time the copyright expires, many of the books are no longer in your library (but probably obtainable by interlibrary loan) That said, I can see the reason for digitizing some of the other (unique)source material first. What I objected to was not wanting to digitze the books at all.
Another benefit is increased life for a given battery size - the heat pipe is a passive device, and allows you to eliminate the cpu fan that would otherwise be required. Heat pipes are very simple, and very reliable. The ones used in laptop are a sealed copper tube containing a wick and a small amount of water. Heat vaporizes some of the liquid, which travels to the other end of the tube, where it condenses. Capillary forces return the liquid water - no outside power (or pump) required. They're probably a lot more reliable than the rest of the laptop - some have been operated continuously for 20 years.
One wonders if the cooling unit mentioned is really a heat pipe. The problem with this is that a heat pipe needs to have a gravity assist to work correctly No, many heat pipes contain a wick that returns the condensed liquid to the CPU by capillary action. Some of the heat pipes can operate with the laptop in any orientation. Maximum adverse elevation for heat pipe technology with water is on the order of 10 meters.
Its pure water, heat pipes can stand being frozen. Alcohol is not added, you would start distilling the alcohol, and end up with a poorly perfoming heat pipe. Distilled water is used because the system is operating a pressure less than atmospheric, and is sensitive to non-condensible gases. For example, copper is used with water in heat pipes, but aluminum is not - the water reacts with the aluminum to form small amounts of alumina, releasing hydrogen - this can impair heat pipe performance.
Actually invented by Gaugler (General Motors) in 1942. Reinvented at Los Alamos in the 60's for cooling thermionic devices (sort of a vacuum tube run "backwards" to generate electricity from heat). I'm somewhat surprised that this came up now. Water heat pipes have been used to cool chips in laptops for 4 to 5 years now. They basically spread out the high heat flux at the cpu to a lower heat flux, that can be more easily dissipated. Big advantage is longer battery life, since you don't need a fan