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Manhole - Game
A manhole (utility hole, maintenance hole, or sewer hole) is an opening to a confined space such as a shaft, utility vault, or large vessel. Manholes, typically protected by a manhole cover, are often used as an access point for an underground public utility, allowing inspection, maintenance, and system upgrades. The majority of underground services have manholes, including water, sewers, telephone, electricity, storm drains, district heating, and gas. Manholes are generally found in urban areas, in streets and occasionally under sidewalks. In rural and undeveloped areas, services such as telephone and electricity are usually carried on utility poles or even pylons rather than underground. In Australia, ''manhole'' also commonly refers to an access hatch used to get access from a room or hallway into the ceiling cavity of a building. These manholes are typically around square. Construction Manhole closings are protected by a grating or manhole cover, a flat plug designe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidewalk
A sidewalk (North American English), pavement (British English, South African English), or footpath (Hiberno-English, Irish English, Indian English, Australian English, New Zealand English) is a path along the side of a road. Usually constructed of concrete, pavers, brick, stone, or asphalt, it is designed for pedestrians. A sidewalk is normally higher than the carriageway, roadway, and separated from it by a curb. There may also be a Road verge, planted strip between the sidewalk and the roadway and between the roadway and the adjacent land. Terminology The preferred term for a pedestrian path beside a road varies based on region. The term "sidewalk" is preferred in most of the United States and Canada. The term "pavement" is more common in the United Kingdom and some other members of the Commonwealth of Nations, as well as parts of the Mid-Atlantic United States such as Philadelphia and parts of New Jersey. Australia, New Zealand, and many other Commonwealth countr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is toxic, corrosive, and flammable. Trace amounts in ambient atmosphere have a characteristic foul odor of rotten eggs. Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777. Hydrogen sulfide is toxic to humans and most other animals by inhibiting cellular respiration in a manner similar to hydrogen cyanide. When it is inhaled or its salts are ingested in high amounts, damage to organs occurs rapidly with symptoms ranging from breathing difficulties to convulsions and death. Despite this, the human body produces small amounts of this sulfide and its mineral salts, and uses it as a signalling molecule. Hydrogen sulfide is often produced from the microbial breakdown of organic matter in the absence of oxygen, such as in swamps and sewers; this process is commonly known as anaerobic digestio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambridge
Cambridge ( ) is a List of cities in the United Kingdom, city and non-metropolitan district in the county of Cambridgeshire, England. It is the county town of Cambridgeshire and is located on the River Cam, north of London. As of the 2021 United Kingdom census, the population of the City of Cambridge was 145,700; the population of the wider built-up area (which extends outside the city council area) was 181,137. (2021 census) There is archaeological evidence of settlement in the area as early as the Bronze Age, and Cambridge became an important trading centre during the Roman Britain, Roman and Viking eras. The first Town charter#Municipal charters, town charters were granted in the 12th century, although modern city status was not officially conferred until 1951. The city is well known as the home of the University of Cambridge, which was founded in 1209 and consistently ranks among the best universities in the world. The buildings of the university include King's College Chap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiberglass
Fiberglass (American English) or fibreglass (English in the Commonwealth of Nations, Commonwealth English) is a common type of fibre-reinforced plastic, fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass cloth. The plastic Matrix (composite), matrix may be a thermoset polymer matrix—most often based on thermosetting polymers such as epoxy, polyester resin, or vinyl ester resin—or a thermoplastic. Cheaper and more flexible than Carbon-fiber-reinforced polymers, carbon fiber, it is stronger than many metals by weight, non-magnetic, non-conductive, transparent to electromagnetic radiation, can be molded into complex shapes, and is chemically inert under many circumstances. Applications include aircraft, boats, automobiles, bath tubs and enclosures, swimming pools, hot tubs, septic tanks, water tanks, roofing, pipes, cladding, orthopedic casts, surfboards, and external door skins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer Propene, propylene. Polypropylene belongs to the group of polyolefins and is Crystallization of polymers#Degree of crystallinity, partially crystalline and Chemical polarity#Nonpolar molecules, non-polar. Its properties are similar to polyethylene, but it is slightly harder and more heat-resistant. It is a white, mechanically rugged material and has a high chemical resistance. Polypropylene is the second-most widely produced Commodity plastics, commodity plastic (after polyethylene). History Phillips Petroleum chemists J. Paul Hogan and Robert Banks (chemist), Robert Banks first demonstrated the polymerization of propylene in 1951. The stereoselective polymerization to the isotactic was discovered by Giulio Natta and Karl Rehn in March 1954. This pioneering discovery led to large-scale commercial producti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Material
A composite or composite material (also composition material) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Composite materials with more than one distinct layer are called ''composite laminates''. Typical engineered composite materials are made up of a binding agent forming the ''matrix'' and a Filler (materials), filler material (particulates or fibres) giving ''substance'', e.g.: * Concrete, reinforced concrete and masonry with cement, lime or Mortar (masonry), mortar (which is itself a composite material) as a binder * Composite wood such as glulam and plywood with wood glue as a binder * Reinforced plastics, such as fiberglass and fibre-rein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass Reinforced Plastic
Fiberglass (American English) or fibreglass (Commonwealth English) is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass cloth. The plastic matrix may be a thermoset polymer matrix—most often based on thermosetting polymers such as epoxy, polyester resin, or vinyl ester resin—or a thermoplastic. Cheaper and more flexible than carbon fiber, it is stronger than many metals by weight, non- magnetic, non-conductive, transparent to electromagnetic radiation, can be molded into complex shapes, and is chemically inert under many circumstances. Applications include aircraft, boats, automobiles, bath tubs and enclosures, swimming pools, hot tubs, septic tanks, water tanks, roofing, pipes, cladding, orthopedic casts, surfboards, and external door skins. Other common names for fiberglass are glass-reinforced plastic (GRP), glass-fiber reinforced plastic (GF ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precast Concrete
Precast concrete is a construction product produced by casting concrete in a reusable molding (process), mold or "form" which is then cured in a controlled environment, transported to the construction site and maneuvered into place; examples include precast beam (structure), beams, and wall panels, floors, roofs, and piles. In contrast, cast-in-place concrete is poured into site-specific forms and cured on site. Recently lightweight expanded polystyrene foam is being used as the cores of precast wall panels, saving weight and increasing thermal insulation. Precast stone is distinguished from precast concrete by the finer construction aggregate, aggregate used in the mixture, so the result approaches the natural product. Overview Precast concrete is employed in both interior and exterior applications, from highway, bridge, and high-rise projects to parking structures, K-12 schools, warehouses, mixed-use, and industrial building construction. By producing precast concrete in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grating
A grating is any regularly spaced collection of essentially identical, parallel, elongated elements. Gratings usually consist of a single set of elongated elements, but can consist of two sets, in which case the second set is usually perpendicular to the first (as illustrated). When the two sets are perpendicular, this is also known as a grid (as in grid paper) or a mesh. As filters A grating covering a drain (as illustrated) can be a collection of iron bars (the identical, elongated elements) held together (to ensure the bars are parallel and regularly spaced) by a lighter iron frame. Gratings over drains and air vents are used as filters, to block movement of large solids (e.g. people) and to allow movement of liquids. A register is a type of grating used in heating, ventilation, and air conditioning, which transmits air, while stopping solid objects. File:Vindobona Hoher Markt-71.JPG, Grating - drain cover, ancient Roman architecture at Vindobona, Austria. File:Montr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manhole Covers In Sidewalk (42839905802)
A manhole (utility hole, maintenance hole, or sewer hole) is an opening to a confined space such as a shaft, utility vault, or large vessel. Manholes, typically protected by a manhole cover, are often used as an access point for an underground public utility, allowing inspection, maintenance, and system upgrades. The majority of underground services have manholes, including water, sewers, telephone, electricity, storm drains, district heating, and gas. Manholes are generally found in urban areas, in streets and occasionally under sidewalks. In rural and undeveloped areas, services such as telephone and electricity are usually carried on utility poles or even pylons rather than underground. In Australia, ''manhole'' also commonly refers to an access hatch used to get access from a room or hallway into the ceiling cavity of a building. These manholes are typically around square. Construction Manhole closings are protected by a grating or manhole cover, a flat plug des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Access Hatch
A trapdoor or hatch is a sliding or hinged door that is flush with the surface of a floor, ceiling, or roof. It is traditionally small in size. It was invented to facilitate the hoisting of grain up through mills, however, its list of uses has grown over time. The trapdoor has played a pivotal function in the operation of the gallows, cargo ships, trains, booby traps, and more recently theatre and films. History Originally, trapdoors were sack traps in mills, and allowed the sacks to pass up through the mill while naturally falling back to a closed position. Many buildings with flat roofs have hatches that provide access to the roof. On ships, hatches—usually not flush, and never called trapdoors—provide access to the deck. Cargo ships, including bulk carriers, have large hatches for access to the holds. Gallows Most 19th- and early 20th-century gallows featured a trapdoor, usually with two flaps. The condemned was placed at the join. The edge of a trapdoor furthest f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
