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Roof Cleaning
Roof cleaning is the process of removing algae, mold, mildew, lichen and moss from roofs. Also cleaning oxidation on metal roofs. Cleaning can extend the duration of a roof's ability to function. Algae and other types of build-up often form on the north and west parts of roofs that are shaded or receive less sun, and can reduce a roof's life expectancy. The presence of soot, dirt, or biomass can affect how much sunlight is absorbed by a roof and thus the amount of heat a building absorbs. Cleaning may be accomplished with a bleach or sodium percarbonate solution, various cleaning products or commercial cleaning services. The Asphalt Roofing Manufacturers Association (ARMA) recommends using a 50/50 solution of household strength sodium hypochlorite (pool chlorine) and water to remove moss and algae. The addition of zinc strips near the roof's peak may reduce the regrowth of algae and moss. Zinc sulfate can also be applied on an annual basis. Cleaning apparatus One safe and effect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size.The elements are from different metal groups. See periodic table. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roofs
A roof ( : roofs or rooves) is the top covering of a building, including all materials and constructions necessary to support it on the walls of the building or on uprights, providing protection against rain, snow, sunlight, extremes of temperature, and wind. A roof is part of the building envelope. The characteristics of a roof are dependent upon the purpose of the building that it covers, the available roofing materials and the local traditions of construction and wider concepts of architectural design and practice, and may also be governed by local or national legislation. In most countries, a roof protects primarily against rain. A verandah may be roofed with material that protects against sunlight but admits the other elements. The roof of a garden conservatory protects plants from cold, wind, and rain, but admits light. A roof may also provide additional living space, for example, a roof garden. Etymology Old English 'roof, ceiling, top, summit; heaven, sky', also f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roofer
A roofer, roof mechanic, or roofing contractor is a tradesperson who specializes in roof construction. Roofers replace, repair, and install the roofs of buildings, using a variety of materials, including shingles, bitumen, and metal. Roofing work can be physically demanding because it involves heavy lifting, as well as climbing, bending, and kneeling, often in extreme weather conditions. Curled or rotten shingles, missing shingles, and blistering are all signs that roof needs attention. Global usage In Australia, this type of carpenter is called a ''roof carpenter'' and the term ''roofer'' refers to someone who installs the roof ''cladding'' (tiles, tin, etc.). In the United States and Canada, they're often referred to as roofing contractors or roofing professionals. The most common roofing material in the United States is asphalt shingles. In the past, 3-tab shingles were used; nowadays, "architectural" or "dimensional" shingles are becoming very popular. Depending on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domestic Roof Construction
Domestic roof construction is the framing (construction), framing and roof covering which is found on most detached houses in cold and temperate climates. Such roofs are built with mostly timber, take a number of different List of roof shapes, shapes, and are covered with a variety of List of commercially available roofing material, materials. Overview Modern timber roofs are mostly framed with pairs of common rafters or prefabricated wooden trusses fastened together with truss connector plates. Timber framed and historic buildings may be framed with principal rafters or timber roof trusses. Roofs are also designated as ''warm'' or ''cold roof'' depending on how they are designed and built with regard to thermal building insulation and Ventilation (architecture), ventilation. The steepness or roof pitch of a sloped roof is determined primarily by the roof covering material and aesthetic design. Flat roofs actually slope up to approximately ten degrees to shed water. Flat roofs ... [...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] |
Radioactive Contamination
Radioactive contamination, also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is unintended or undesirable (from the International Atomic Energy Agency (IAEA) definition). Such contamination presents a hazard because the radioactive decay of the contaminants, produces ionizing radiation (namely alpha, beta, gamma rays and free neutrons). The degree of hazard is determined by the concentration of the contaminants, the energy of the radiation being emitted, the type of radiation, and the proximity of the contamination to organs of the body. It is important to be clear that the contamination gives rise to the radiation hazard, and the terms "radiation" and "contamination" are not interchangeable. The sources of radioactive pollution can be classified into two groups: natural and man-made. Following an atmospheric nuclear weapon discharge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Sulfate
Zinc sulfate is an inorganic compound. It is used as a dietary supplement to treat zinc deficiency and to prevent the condition in those at high risk. Side effects of excess supplementation may include abdominal pain, vomiting, headache, and tiredness. The most common form includes water of crystallization as the heptahydrate, with the formula . It was historically known as "white vitriol". Zinc sulfate and its hydrates are colourless solids. Uses Medicine In medicine it is used together with oral rehydration therapy (ORT) and an astringent. Manufacturing The hydrates, especially the heptahydrate, are the primary forms used commercially. The main application is as a coagulant in the production of rayon. It is also a precursor to the pigment lithopone. It is also used as an electrolyte for zinc electroplating, as a mordant in dyeing, and as a preservative for skins and leather. Other Zinc sulfate is used to supply zinc in animal feeds, fertilizers, toothpaste, and agricul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hypochlorite
Sodium hypochlorite (commonly known in a dilute solution as bleach) is an Inorganic chemistry, inorganic chemical compound with the chemical formula, formula NaOCl (or NaClO), comprising a sodium cation () and a hypochlorite anion (or ). It may also be viewed as the sodium salt (chemistry), salt of hypochlorous acid. The anhydrous Chemical compound, compound is unstable and may decompose explosively. It can be crystallized as a hydrate, pentahydrate ·5, a pale greenish-yellow solid which is not explosive and is stable if kept refrigerated. Sodium hypochlorite is most often encountered as a pale greenish-yellow dilute solution referred to as liquid bleach, which is a household chemical widely used (since the 18th century) as a disinfectant or a bleaching agent. In solution, the compound is unstable and easily decomposes, liberating chlorine, which is the active principle of such products. Sodium hypochlorite is the oldest and still most important chlorine-releasing compounds, chl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gloeocapsa Magma On Shingles
''Gloeocapsa'' (from the Greek ''gloia'' (gelatinous) and the Latin ''capsa'' (case)) is a genus of cyanobacteria. The cells secrete individual gelatinous sheaths which can often be seen as sheaths around recently divided cells within outer sheaths. Recently divided cell pairs often appear to be only one cell since the new cells cohere temporarily. They are also known as glow caps, a term derived from the yellowish hue given off by the cap. Occurrence Some species of this genus are halophiles and hence found in hypersaline lakes and other high salinity environments. An example of such occurrence of the genus is in the Makgadikgadi Pans of Botswana Botswana (, ), officially the Republic of Botswana ( tn, Lefatshe la Botswana, label=Setswana, ), is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory being the Kalahar .... '' Gloeocapsa magma'' is noted for colonising roof shingles in the United States and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Percarbonate
Sodium percarbonate is a chemical substance with formula . It is an adduct of sodium carbonate ("soda ash" or "washing soda") and hydrogen peroxide (that is, a perhydrate) whose formula is more properly written as 2 · 3 . It is a colorless, crystalline, hygroscopic and water-soluble solid. It is sometimes abbreviated as SPC. It contains 32.5% by weight of hydrogen peroxide. The product is used in some eco-friendly bleaches and other cleaning products itation needed History Sodium percarbonate was first prepared in 1899 by Russian chemist Sebastian Moiseevich Tanatar (7 October 1849 – 30 November 1917). Structure At room temperature, solid sodium percarbonate has the orthorhombic crystal structure, with the ''Cmca'' crystallographic space group. The structure changes to ''Pbca'' as the crystals are cooled below about −30 °C. Chemistry Dissolved in water, sodium percarbonate yields a mixture of hydrogen peroxide (which eventually decomposes t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bleach
Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to a dilute solution of sodium hypochlorite, also called "liquid bleach". Many bleaches have broad spectrum bactericidal properties, making them useful for disinfecting and sterilizing. They are used in swimming pool sanitation to control bacteria, viruses, and algae, and in many places where sterile conditions are required. They are also used in many industrial processes, notably in the bleaching of wood pulp. Bleaches also have other minor uses like removing mildew, killing weeds, and increasing the longevity of cut flowers. Bleaches work by reacting with many colored organic compounds, such as natural pigments, and turning them into colorless ones. While most bleaches are oxidizing agents (chemicals that can remove electrons from other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
