The pore sizes of microporous surfaces are comparable to the size of molecules. Water management, gas separation, oil recovery and the removal of organic and metal contaminants from process streams all use microporous surfaces. Macroporous surfaces have large pores that allow the smooth movement of water and air. In plating, the base metal is exposed through pores. The degree of porosity depends on plating thickness, application method, base metal roughness and base metal cleanliness.
Porosity decreases with the increase of plating thickness. Rough metal surfaces, and dirt or oxide on the surface of the base metal lead to the appearance of pores. Pore corrosion results when the base metal is exposed to a corrosive environment through these pores. This may cause base metal corrosion or the corrosion product may creep across the surface. This corrosion can be minimized by using thicker coatings. PM stainless steels have weak corrosion resistance due to porosity, and this leads to crevice corrosion.
This corrosion resistance is improved when a greater percentage of the porosity is sealed. Surface porosity can be reduced by using a chemical vapor deposition CVD process. Holes, hollows and dips.
You can also find related words, phrases, and synonyms in the topics: Weakness and vulnerability. Examples of porous. X-ray streak camera is used for evaluation of the speed of energy transfer through the porous foam material. From the Cambridge English Corpus. Effects of salt concentration changes during freezing on the unfrozen water content of porous materials. Discussion was itself understood as enacting social change - it was the sign of a more porous but also more rational society.
They did not necessarily halt the traffic- porous borders and administrative graft militated against the effectiveness of bans and controls-but prices were usually not left unaffected. In general, the evidence is that biofilm that is closest to the substratum has the highest density, while the top layers remain "fluffy" and porous. Coupled parallel flows in a channel and bounding porous medium of finite thickness.
Experimentally, it has been proven that the fine porous nano-structure of aerogels does not affect the ion energy loss and charge state distribution. The porous medium is endowed with a heterogeneous microstructure. The dissolution and precipitation of crystals in porous media have been studied also in [7, 12] and [14, 17]. In such systems the initial sample would be prepared and separated by standard electrophoretic or porous membrane techniques.
A rock with good porosity is an important characteristic for an oil well. When oil or gas is exposed to a porous rock, it seeps through the holes in the rock and becomes contained between the grains. Due to this, there is actually no "ocean of oil" beneath ground—rather it is trapped within porous rocks such as sandstone. Fossil Fuels.
Nuclear Fuels. Acid Rain. English Language Learners Definition of porous. Kids Definition of porous. Medical Definition of porous. Get Word of the Day daily email! Test Your Vocabulary. Test your vocabulary with our question quiz! Love words? Need even more definitions? Homophones, Homographs, and Homonyms The same, but different.
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