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Acoustic Plaster
Acoustic plaster is plaster which contains fibres or aggregate so that it absorbs sound. Early plasters contained asbestos, but newer ones consist of a base layer of absorptive substrate panels, which are typically mineral wool, or a non-combustible inorganic blow-glass granulate. A first finishing layer is then applied on top of the substrate panels, and sometimes a second finishing layer is added for greater sound attenuation. Pre-made acoustic panels are more commonly used, but acoustic plaster provides a smooth and seamless appearance, and greater flexibility for readjustment. The drawback is the greater level of skill required in application. Proprietary types of acoustic plaster developed in the 1920s included Macoustic Plaster, Sabinite, Kalite, Wyodak, Old Newark and Sprayo-Flake produced by companies such as US Gypsum. Basic composition Acoustic plasters are aesthetically favorable because it allows for seamless smooth application compared to panels that show visible jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plaster
Plaster is a building material used for the protective or decorative coating of walls and ceilings and for Molding (decorative), moulding and casting decorative elements. In English, "plaster" usually means a material used for the interiors of buildings, while "render" commonly refers to external applications. Another imprecise term used for the material is stucco, which is also often used for plasterwork that is worked in some way to produce relief decoration, rather than flat surfaces. The most common types of plaster mainly contain either gypsum, lime plaster, lime, or cement plaster, cement,Franz Wirsching "Calcium Sulfate" in Ullmann's Encyclopedia of Industrial Chemistry, 2012 Wiley-VCH, Weinheim. but all work in a similar way. The plaster is manufactured as a dry powder and is mixed with water to form a stiff but workable paste immediately before it is applied to the surface. The reaction with water liberates heat through crystallization and the hydrated plaster then ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absorption (acoustics)
Acoustic absorption refers to the process by which a material, structure, or object takes in sound energy when sound waves are encountered, as opposed to reflecting the energy. Part of the absorbed energy is transformed into heat and part is transmitted through the absorbing body. The energy transformed into heat is said to have been 'lost'.Acoustic Absorbers and Diffusers: Theory, Design and Applicatio.CRC Press .2009.Peter D'Antoni When sound from a loudspeaker collides with the walls of a room part of the sound's energy is reflected, part is transmitted, and part is absorbed into the walls. Just as the acoustic energy was transmitted through the air as pressure differentials (or deformations), the acoustic energy travels through the material which makes up the wall in the same manner. Deformation causes mechanical losses via conversion of part of the sound energy into heat, resulting in acoustic attenuation, mostly due to the wall's viscosity. Similar attenuation mechanisms ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asbestos
Asbestos () is a naturally occurring fibrous silicate mineral. There are six types, all of which are composed of long and thin fibrous crystals, each fibre being composed of many microscopic "fibrils" that can be released into the atmosphere by abrasion and other processes. Inhalation of asbestos fibres can lead to various dangerous lung conditions, including mesothelioma, asbestosis, and lung cancer, so it is now notorious as a serious health and safety hazard. Archaeological studies have found evidence of asbestos being used as far back as the Stone Age to strengthen ceramic pots, but large-scale mining began at the end of the 19th century when manufacturers and builders began using asbestos for its desirable physical properties. Asbestos is an excellent electrical insulator and is highly fire-resistant, so for much of the 20th century it was very commonly used across the world as a building material, until its adverse effects on human health were more widely acknowledged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral Wool
Mineral wool is any fibrous material formed by spinning or drawing molten mineral or rock materials such as slag and ceramics. Applications of mineral wool include thermal insulation (as both structural insulation and pipe insulation), filtration, soundproofing, and hydroponic growth medium. Naming Mineral wool is also known as ''mineral fiber'', ''mineral cotton'', ''mineral fibre'', ''man-made mineral fibre'' (MMMF), and ''man-made vitreous fiber'' (MMVF). Specific mineral wool products are ''stone wool'' and ''slag wool''. Europe also includes glass wool which, together with ceramic fiber, are entirely artificial fibers that can be made into different shapes and are spiky to touch. History Slag wool was first made in 1840 in Wales by Edward Parry, "but no effort appears to have been made to confine the wool after production; consequently it floated about the works with the slightest breeze, and became so injurious to the men that the process had to be abandoned". ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USG Corporation
USG Corporation, also known as United States Gypsum Corporation, is an American company which manufactures construction materials, most notably drywall and joint compound. The company is the largest distributor of wallboard in the United States and the largest manufacturer of gypsum products in North America. It is also a major consumer of synthetic gypsum, a byproduct of flue-gas desulfurization. Its corporate offices are located at 550 West Adams Street in Chicago, Illinois. Together with other construction products, USG's most significant brands are: :* Sheetrock Brand Gypsum Panels :* Securock Brand Glass-Mat Sheathing :* Sheetrock Brand All Purpose Joint Compound In December 2013, Warren Buffett's Berkshire Hathaway became the largest shareholder in the company (holding roughly 30%) when it converted USG convertible notes it had acquired in 2008 to common stock. In June 2018, USG entered into an agreement to be purchased by the German building materials company Knauf. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composition Of Plaster Layers
Composition or Compositions may refer to: Arts and literature *Composition (dance), practice and teaching of choreography *Composition (language), in literature and rhetoric, producing a work in spoken tradition and written discourse, to include visuals and digital space *Composition (music), an original piece of music and its creation *Composition (visual arts), the plan, placement or arrangement of the elements of art in a work * ''Composition'' (Peeters), a 1921 painting by Jozef Peeters *Composition studies, the professional field of writing instruction * ''Compositions'' (album), an album by Anita Baker *Digital compositing, the practice of digitally piecing together a video Computer science *Function composition (computer science), an act or mechanism to combine simple functions to build more complicated ones *Object composition, combining simpler data types into more complex data types, or function calls into calling functions History *Composition of 1867, Austro-Hungarian/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auditorium
An auditorium is a room built to enable an audience to hear and watch performances. For movie theatres, the number of auditoria (or auditoriums) is expressed as the number of screens. Auditoria can be found in entertainment venues, community halls, and theaters, and may be used for rehearsal, presentation, performing arts productions, or as a learning space. Etymology The term is taken from Latin (from ''audītōrium'', from ''audītōrius'' ("pertaining to hearing")); the concept is taken from the Greek auditorium, which had a series of semi-circular seating shelves in the theatre, divided by broad 'belts', called ''diazomata'', with eleven rows of seats between each. Auditorium structure The audience in a modern theatre are usually separated from the performers by the proscenium arch, although other types of stage are common. The price charged for seats in each part of the auditorium (known in the industry as the house) usually varies according to the quality o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Library
A library is a collection of materials, books or media that are accessible for use and not just for display purposes. A library provides physical (hard copies) or digital access (soft copies) materials, and may be a physical location or a virtual space, or both. A library's collection can include printed materials and other physical resources in many formats such as DVD, CD and cassette as well as access to information, music or other content held on bibliographic databases. A library, which may vary widely in size, may be organized for use and maintained by a public body such as a government; an institution such as a school or museum; a corporation; or a private individual. In addition to providing materials, libraries also provide the services of librarians who are trained and experts at finding, selecting, circulating and organizing information and at interpreting information needs, navigating and analyzing very large amounts of information with a variety of resources. Li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felt
Felt is a textile material that is produced by matting, condensing and pressing fibers together. Felt can be made of natural fibers such as wool or animal fur, or from synthetic fibers such as petroleum-based acrylic or acrylonitrile or wood pulp–based rayon. Blended fibers are also common. Natural fibre felt has special properties that allow it to be used for a wide variety of purposes. "It is fire-retardant and self-extinguishing; it dampens vibration and absorbs sound; and it can hold large amounts of fluid without feeling wet..." History Felt from wool is one of the oldest known textiles. Many cultures have legends as to the origins of felt making. Sumerian legend claims that the secret of feltmaking was discovered by Urnamman of Lagash. The story of Saint Clement and Saint Christopher relates that the men packed their sandals with wool to prevent blisters while fleeing from persecution. At the end of their journey, the movement and sweat had turned the wool into f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quilt
A quilt is a multi-layered textile, traditionally composed of two or more layers of fabric or fiber. Commonly three layers are used with a filler material. These layers traditionally include a woven cloth top, a layer of batting or wadding, and a woven back combined using the techniques of quilting. This is the process of sewing on the face of the fabric, and not just the edges, to combine the three layers together to reinforce the material. Stitching patterns can be a decorative element. A single piece of fabric can be used for the top of a quilt (a "whole-cloth quilt"), but in many cases the top is created from smaller fabric pieces joined, or patchwork. The pattern and color of these pieces creates the design. Quilts may contain valuable historical information about their creators, "visualizing particular segments of history in tangible, textured ways." In the twenty-first century, quilts are frequently displayed as non-utilitarian works of art but historically quilts were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustic Tile
A dropped ceiling is a secondary ceiling, hung below the main (structural) ceiling. It may also be referred to as a drop ceiling, T-bar ceiling, false ceiling, suspended ceiling, grid ceiling, drop in ceiling, drop out ceiling, or ceiling tiles and is a staple of modern construction and architecture in both residential and commercial applications. History Dropped ceilings and ceiling tiles were used in Japan for aesthetic reasons as early as the Muromachi Period (1337 to 1573).Interview with Matthew Welch, Curator of Japanese and Korean Art, Minneapolis Institute of Arts retrieved January 12, 2014 These could be made with simple planks, or [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustics
Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an Acoustical engineering, acoustical engineer. The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries. Hearing (sense), Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture. Accordingly, the science of acoustics spreads across many facets of human society—music, medicine, architecture, industrial production, warfare and more. Likewise, animal species such as songbirds and frogs use sound and hearing as a key element of mating rituals or for marking territories. Art, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
