Word: layering
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...issue you mentioned a 60-year-old Philadelphia woman who got a skin rash after gathering cashew nuts in Ceylon. When it is picked from the tree, the cashew nut is covered with a hard tough shell that has a thin layer of black oil underneath. This oil is quite corrosive to the skin. It is in the shell, however, which is left in India -in fact is used for fuel-and is not in the kernel that...
...cost materials like foods. Another difficulty is that a considerable amount of heat (heat of sublimation) is required to evaporate the ice crystals. This heat must reach the center of the material, and in the case of most foods the evaporation of crystals near the surface forms a layer of corklike stuff that is an excellent insulator. It keeps heat of sublimation from reaching the interior unless the surface temperature is raised so high that the food spoils...
...long as these "dirty snowballs" stay far enough from the sun, as most of them do, they lead peaceful lives, but a plunge toward the center of the solar system is a wild adventure. As a comet approaches the sun, its surface is warmed by the strengthening sunlight. Layer after layer, the ices turn into gas. Soon the nucleus is surrounded by a rapidly growing cloud, of gas and dust boiled out of the solid nucleus. This cloud, the comet's head, may be many thousands of miles in diameter. It is so transparent that stars show through...
...depositing the coatings was done by the Army Engineers at Fort Belvoir, Va. Each satellite was put in a vacuum chamber and turned, like a chicken on a spit while the materials in the coatings were evaporated electrically and deposited on its surface. The final coat was a second layer of silicon monoxide...
...Freeze. The two outer layers determine the satellite's reaction to solar radiation. Silicon monoxide is transparent to visible light, so the powerful visible part of the sun's radiation penetrates to the shiny aluminum and is mostly reflected back into space. The temperature of the aluminum rises slowly, both because it is a poor absorber and because the silicon monoxide layer in contact with it is a comparatively good radiator of infra-red (heat) rays. By experimenting with different thicknesses of silicon monoxide, the Navy's scientists think they can keep the temperature of the skin...