12/31/2013

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Basis Polyurethane Curing the film in air can side reaction of isocyanate groups with water, leading eventually to the formation of urea linkages. The industry can be one and the same method to obtain different PU coating materials. For example, in the same pattern of production coatings, moisture curing, can be obtained on the basis of products alcoholysis of castor oil and glycerin, respectively, triethanolamine odnoupakovochnye dvuhupakovochnye and materials. To obtain two-component systems have found applications such as polyisocyanates, biuret-polyisocyanate how to cure without heating only in the presence of catalysts (octoate and naphthenate zinc). Coatings based on this have a lower hardness, but a good color - and weatherproof. The domestic industry produces aliphatic poliizo - cyanate, biuret based on hexamethylene diisocyanate and water. But they do not mix, so the water injected into the mixture with a solvent (dioxane or acetone). In the commercially available two-component system consisting of semi-finished products of enamel and a polyisocyanate curing agent mixed before use. Semi-finished enamel - suspension of pigments and fillers, additives to the target in a solution of resin. Hardeners are available in sets. Relatively new type of polyurethane coatings are aqueous compositions that are growing application, staining wood, plastic, metal and other materials. Especially popular are water dvuhupakovochnye polyurethanes. They are ideally suited for corrosion resistant coatings on metal. The major consumers of such materials are the automotive, automobile repair sector, as well as manufacturers of military equipment that use dvuhupakovochnye polyurethane dispersion with a volatile content less than 180 g / l, allowing form a thermo - and chemically resistant topcoat for aircraft and tactical weapons. The most common type of water paint for wood is a mixture of polyurethane dispersions and acrylic latexes, hybrid akriluretanovye dispersion and composition based on akriluretanov with particles of the core / shell....
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Ancient Egyptian Civilization Religious aspects: the Egyptian cosmogony. They are not projects of men that are made, but the will of Dios Ptahotep NACK 1996: 110 in the religious life of the Egyptians, we get to meet a chaotic multiplicity of names and figures of divinities. This is due to that before the unification of the Kingdom, each one of the tribes that inhabited the oasis of the Nile had his own God guard and that Egyptian religion Furthermore, resting on a multiplicity of divine powers, since they believed that the soul separated from matter acts as Rector of organic existence. These souls live in all things and all beings and are the cause of natural phenomena. The Egyptians are the most religious men, said Herodotus. The creation of the world - as the majority of primitive peoples, also the Egyptians tried to explain the origin of the universe, which can be summarized this way explanation: said that only initially there was the ocean. The chaos of the waters immense emerged coordinated worldwide. An egg emerges from the sea, and he was born the Sun God, Ra. It has four children: Sju and Sefnut, Geb and Nut. GEB, God of the Earth, has the shape of a rough man, which corresponds to the Strait and length of the Nile Valley; plants grow on his back. Nut is lifted into space on top of her husband and becomes the goddess of heaven, which leans on the Earth. GEB and Nut then are the parents of two couples of divine Osiris and Isis, Set and Nephtys. So, the Egyptian cosmogonic myth not is the creation of the world from nothing, but a separation and sorting of chaos. This creation myth resulted in the conception of the Ennead, a group of nine deities, and the triad,...