A ceramic is an inorganic, nonmetallica hard material comprising metal, nonmetal or metalloid atoms mainly held in ionic and covalent bonds. The crystallinity of ceramic materials varies from greatly oriented to semi crystalline, and frequently totally amorphous e.G., glasses . Varying crystallinity and electron intake in the ionic and covalent bonds because most ceramic materials to be good thermal and electrical insulators and greatly researched in ceramic engineering. With such a big range of possible alternatives for the composition/structure of a ceramic e.G. almost all of the elements, almost all types of bonding, and all levels of crystallinity , the breadth of the subject is vast, and identifiable attributes e.G. Hardness, toughness, electrical conductivity, etc. Are hard to identify for the group all together. General properties like high melting temperature, high hardness, poor conductivity, high moduli of elasticity, chemical resistance and low ductility are the norm,1 with recognized exemptions to each of these rules e.G. Piezoelectric ceramics, glass transition temperature, superconductive ceramics, etc. . Many composites, like fiberglass and carbon fiber, while containing ceramic materials, aren’t considered to be part of the ceramic family.
The earliest recognized talk about of the root “ceram ” is the Mycenaean Greek ke ra me we, “workers of ceramics”, written in Linear B syllabic script.5 The word “ceramic” can be used as an adjective to describe a material, product or procedure, or it can be used as a noun, either singular, or, more usually, as the plural noun “ceramics”.
The earliest ceramics made by humans were pottery objects, as well as 27,000-year old figurines, made from clay, by itself or mixed with other materials like silica, hardened, sintered, in fire. afterward ceramics were glazed and fired to create smooth, colored surfaces, decreasing porosity through the use of glassy, amorphous ceramic coatings over the crystalline ceramic substrates.7 Ceramics now include domestic, industrial and building merchandise, also as a large range of ceramic art. In the 20th century, new ceramic materials were worked on for use in advanced ceramic engineering, like in semiconductors.
A curtain on occasion called a drape, primarily in the United States is a part of cloth meant to block or obscure light, or drafts, or water in the case of a shower curtain.1 A curtain is the movable screen or drape in a theater that separates the stage from the auditorium or that serves as a backdrop.1
Curtains hung over a doorway are called portires. Curtains are frequently hung on the inside of a building’s windows to block the passage of light, for example at night to aid sleeping, or to stop light from escaping outside the building stopping people outside from being able to see inside, frequently for privacy reasons , and in this application, they’re aka “draperies”. Curtains come in a range of shapes, materials, sizes, colors and patterns, and they frequently have their own sections inside department stores, while some shops are totally dedicated to selling curtains.
Curtains differ as indicated by cleanability, ultraviolet light deterioration, oil and dust retention, sound absorption, fire resistance, and life span. Curtains can be moved by hand, with cords, by press button pads or remote controlled computers. they’re held out of the way of the window by means of curtain tie backs. Measuring curtain sizes needed for each window differs largely as indicated by the kind of curtain needed, window size, and type and weight of curtain.
Curtains are a form of window treatment, and complete the in general look of the house. Window treatment helps control the atmosphere and flow of natural light into the room. The effect of drapery or curtains is best seen in daylight, and with correct indoor light positioning, can look nice at night.