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Durable water repellent, or DWR, is a coating added to fabrics at the factory to make them water-resistant (hydrophobic). Most factory-applied treatments are fluoropolymer based; these applications are quite thin and not always effective.
Waterproof paper uses special coatings (plastic-coated paper) and fibers to enhance durability, dimensional stability, tear resistance and resistance to changing shape or texture when exposed to water.
J-B Weld epoxy is a two-part adhesive that can bond various surfaces and withstand high temperatures up to 500 °F (260 °C) constantly and 600 °F (316 °C) for short periods. It is water-resistant, petroleum/chemical-resistant, acid-resistant, and resists shock, vibration, and temperature fluctuations.
For gases (e.g. nitrogen, sulfur hexafluoride) it normally decreases with increased humidity as ions in water can provide conductive channels. For gases it increases with pressure according to Paschen's law; For air, dielectric strength increases slightly as the absolute humidity increases but decreases with an increase in relative humidity [2]
Besides its water resistance, glass is also robust when exposed to certain chemically-aggressive liquids or gases. Glass disease is the corrosion of silicate glasses in aqueous solutions . It is governed by two mechanisms: diffusion - controlled leaching (ion exchange) and hydrolytic dissolution of the glass network. [ 16 ]
Nichrome (also known as NiCr, nickel-chromium or chromium-nickel) is a family of alloys of nickel and chromium (and occasionally iron [1]) commonly used as resistance wire, heating elements in devices like toasters, electrical kettles and space heaters, in some dental restorations (fillings) and in a few other applications.
Water is also central to acid-base neutrality and enzyme function. An acid, a hydrogen ion (H +, that is, a proton) donor, can be neutralized by a base, a proton acceptor such as a hydroxide ion (OH −) to form water. Water is considered to be neutral, with a pH (the negative log of the hydrogen ion concentration) of 7 in an ideal state.
The SI unit of absolute thermal resistance is kelvins per watt (K/W) or the equivalent degrees Celsius per watt (°C/W) – the two are the same since the intervals are equal: ΔT = 1 K = 1 °C. The thermal resistance of materials is of great interest to electronic engineers because most electrical components generate heat and need to be cooled.