Glass

=Glass =



===Glass is an amorphous solid that has been aorund in various forms for thousands of years and has been manufactured for human use since 12.000 BCE. Glass is one the most versatile substances on Earth, used in many applications and in a wide variety of forms, from plain clear glass to tempered and tinted varieties, and so foth. ===


 * ===Solid and hard material ===
 * ===Disordered and amorphous structure[[image:glassrecycle.jpg width="225" height="226" align="right"]] ===
 * ===Fragile and easily breakable into sharp pieces ===
 * ===Transparent to visible light ===
 * ===Inert and biologically inactive material ===
 * ===Glass is 100% recycable and one of the safest packaging materials due to its composition and properties. ===

//__ 'Ordinary' sheet glass __ //
===This glass is made by passing the molten glass through rollers; this process gives an almost flat finish but the effects of the rollers upon the molten glass makes some inevitable distortion. Sheet glasses usually use to glazing greenhouses and garden sheds where the visual distortions do not matter. ===



__ Float glass (plate) __
===Float glass gets its name from the method of production used to manufacture it. The molten glass is 'floated' onto a bed of molten tin, this produces a glass which is flat and distortion free. ===



__ //Energy efficient glass// __
===Some manufacturers produce float glass with a special thin coating on one side which allows the suns energy to pass through in one direction while reducing the thermal transfer the other way. The principle behind this is the difference in thermal wavelength of energy transmitted from the sun and that transmitted from the heat within a room. ===



//__Self cleaning glass__ //
=== Some manufacturers produce float glass with a special thin 'photocatalytic' coating on one side. This coating uses the ultraviolet rays from the sun to steadily break down any organic dirt on the surface using the photocatalytic effect and thus loosen the dirt from the glass. ===



//<span style="color: black; font-family: 'Comic Sans MS',cursive;">__Patterned (obscured glass)__ //
===<span style="color: black; font-family: 'Comic Sans MS',cursive;"> Made from flat glass, this type has a design rolled onto one side during manufacture. It can be used for decorative effect and/or to provide privacy. Patterned glass is available in a range of coloured tints as well as plain. ===



//__<span style="color: black; font-family: 'Comic Sans MS',cursive;">Toughened (Safety glass) __//
===<span style="color: black; font-family: 'Comic Sans MS',cursive;"> Toughened glass is produced by applying a special treatment to ordinary float glass after it has been cut to size and finished. The treatment involves heating the glass so that it begins to soften (about 620 degrees C) and then rapidly cooling it. This produces a glass which, if broken, breaks into small pieces without sharp edges. The treatment does increase the surface tension of the glass which can cause it to 'explode' if broken. ===



//<span style="color: black; font-family: 'Comic Sans MS',cursive;">__Mirrors__ //
===<span style="font-family: 'Comic Sans MS',cursive;"> Mirrors are usually made from float glass 4-6mm thick. It is a type of glass at least one reflective surface. The most familiar type of mirror is the plane mirror, which has a flat surface. Curved mirrors are also used, to produce magnified or diminished images or focus light or simply distort the reflected image. ===



<span style="color: #ff005d; font-family: 'Comic Sans MS',cursive;">Paragraph 3
===<span style="font-family: 'Comic Sans MS',cursive;">The use of glass in Caracas is increasingly used as a sign of architectural innovation, it is mostly used in office buildings, trying to create an atmosphere of work when you have a vision of the landscape of the city. This has been done to sell more the image of a building, but architects have neglected the problems that could bring its excessive use, such as ventilation and water filtration. For this we must know how to use glass and not abuse its use. === ===<span style="font-family: 'Comic Sans MS',cursive;"> Despite these problems that may occur, in Caracas, the architects have tried to use this material to make the city more contemporary and look more advanced in its architecture. But one negative aspect is that is has been used in a disorderly way, that is, buildings have been built with this material in spaces dominated by the use of concrete, this breaks the architectural line of the City and produces a disorder in it. === ===<span style="font-family: 'Comic Sans MS',cursive;"> All of these problems that occur with the use of glass offer us a challenge; we must not deny these innovations, we must continue working to further refine the use of this material. ===



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