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Tarnish
Tarnish is a thin layer of corrosion that forms over copper, brass, aluminum, magnesium, neodymium and other similar metals as their outermost layer undergoes a chemical reaction. Tarnish does not always result from the sole effects of oxygen in the air. For example, silver needs hydrogen sulfide to tarnish, although it may tarnish with oxygen over time. It often appears as a dull, gray or black film or coating over metal. Tarnish is a surface phenomenon that is self-limiting, unlike rust. Only the top few layers of the metal react. The layer of tarnish seals and protects the underlying layers from reacting. Tarnish preserves the underlying metal in outdoor use, and in this form is called chemical patina, an example of which is the green or blue-green form of copper(II) carbonate known as verdigris. Unlike patina advantageous in applications such as copper roofing and copper, bronze, and brass statues and fittings exposed to the elements, a chemical patina may be considered u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patina
Patina ( or ) is a thin layer that variously forms on the surface of copper, brass, bronze, and similar metals and metal alloys ( tarnish produced by oxidation or other chemical processes), or certain stones and wooden furniture (sheen produced by age, wear, and polishing), or any similar acquired change of a surface through age and exposure. Additionally, the term is used to describe the aging of high-quality leather. The patinas on leather goods are unique to the type of leather, frequency of use, and exposure. Patinas can provide a protective covering to materials that would otherwise be damaged by corrosion or weathering. They may also be aesthetically appealing. Usage On metal, patina is a coating of various chemical compounds such as oxides, carbonates, sulfides, or sulfates formed on the surface during exposure to atmospheric elements (oxygen, rain, acid rain, carbon dioxide, sulfur-bearing compounds). Patina also refers to accumulated changes in surface texture and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable, unalloyed metallic form. This means that copper is a native metal. This led to very early human use in several regions, from . Thousands of years later, it was the first metal to be smelted from sulfide ores, ; the first metal to be cast into a shape in a mold, ; and the first metal to be purposely alloyed with another metal, tin, to create bronze, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolfram Evaporated Crystals And 1cm3 Cube
Wolfram may refer to: * Wolfram (name), a Germanic masculine given name and a surname (includes a list of people with the name) * Wolfram (musician), an Austrian DJ * Wolfram (element), the original name for the chemical element best known as tungsten * Wolfram Research, a software company known for the symbolic computation program Mathematica ** Wolfram Language The Wolfram Language ( ) is a proprietary, very high-level multi-paradigm programming language developed by Wolfram Research. It emphasizes symbolic computation, functional programming, and rule-based programming and can employ arbitrary stru ..., the programming language used by Mathematica ** Wolfram code, a naming system for one-dimensional cellular automaton rules introduced by Stephen Wolfram * Wolfram syndrome, a genetic disorder * Wolfram, Queensland, a former mining town in Australia * The ''Wolfram'', a fictional military airship in the air combat video game '' The Sky Crawlers: Innocent Aces'' {{ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver
Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. Silver is found in the Earth's crust in the pure, free elemental form ("native metal, native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc Refining (metallurgy), refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes bimetallism, alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. Other than in currency and as an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Carbonate
Calcium carbonate is a chemical compound with the chemical formula . It is a common substance found in Rock (geology), rocks as the minerals calcite and aragonite, most notably in chalk and limestone, eggshells, gastropod shells, shellfish skeletons and pearls. Materials containing much calcium carbonate or resembling it are described as calcareous. Calcium carbonate is the active ingredient in agricultural lime and is produced when calcium ions in hard water react with carbonate ions to form limescale. It has medical use as a calcium supplement or as an antacid, but excessive consumption can be hazardous and cause hypercalcemia and digestive issues. Chemistry Calcium carbonate shares the typical properties of other carbonates. Notably, it: *reacts with acids, releasing carbonic acid which quickly disintegrates into carbon dioxide and water: : *releases carbon dioxide upon heating, called a thermal decomposition reaction, or calcination (to above 840 °C in the case of ), t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Bicarbonate
Sodium bicarbonate ( IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda (or simply “bicarb” especially in the UK) is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cation ( Na+) and a bicarbonate anion (). Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda ( sodium carbonate). The natural mineral form is nahcolite, although it is more commonly found as a component of the mineral trona. As it has long been known and widely used, the salt has many different names such as baking soda, bread soda, cooking soda, brewing soda and bicarbonate of soda and can often be found near baking powder in stores. The term ''baking soda'' is more common in the United States, while ''bicarbonate of soda'' is more common in Australia, the United Kingdom, and New Zealand. Abbreviated colloquial forms such as '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polishing
Polishing is the process of creating a smooth and shiny surface by rubbing it or by applying a chemical treatment, leaving a clean surface with a significant specular reflection (still limited by the index of refraction of the material according to the Fresnel equations). In some materials (such as metals, glasses, black or transparent stones), polishing is also able to reduce diffuse reflection to minimal values. When an unpolished surface is magnified thousands of times, it usually looks like a succession of mountains and valleys. By repeated abrasion, those "mountains" are worn down until they are flat or just small "hills". The process of polishing with abrasives starts with a coarse grain size and gradually proceeds to the finer ones to efficiently flatten the surface imperfections and to obtain optimal results. Mechanical properties The strength of polished products can be higher than their unpolished counterparts owing to the removal of stress concentrations pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emery Paper
upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)) Sandpaper, also known as coated abrasive or emery paper, is a type of material that consists of sheets of paper or cloth with an abrasive substance glued to one face. In the modern manufacture of these products, sand and glass have been replaced by other abrasives such as aluminium oxide or silicon carbide. It is common to use the name of the abrasive when describing the paper, e.g. "aluminium oxide paper", or "silicon carbide paper". There are many varieties of sandpaper, with variations in the paper or backing, the material used for the grit, grit size, and the bond. Sandpaper is produced in a range of grit sizes and is used to remove material from surfaces, whether to make them smoother (for example, in painting and wood finishing), to remove a layer of material (such as old paint), or sometimes to make the surface rougher (for example, as a preparation for gluing). The grit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel Wool
Steel wool, also known as iron wool or wire sponge, is a bundle of very fine and flexible sharp-edged steel filaments. It is the most common type of wire wool and is often the type meant when wire wool is mentioned. It was described as a new product in 1896.''Iron Age'', Vol. LVII, p.871, cited by ''Journal of the Iron and Steel Institute'', Volume 50, Issue 2, p.48/ref> It is used as an abrasive in finishing and repair work for polishing wood or metal objects, cleaning household cookware, cleaning windows, and sanding surfaces. Steel wool is made from low-carbon steel in a process similar to broach (metalworking), broaching, where a heavy steel wire is pulled through a toothed die that removes thin, sharp, wire shavings. Uses Steel wool is commonly used by woodworkers, metal craftsmen, and jewelers to clean and smooth working surfaces and give them shine. However, when used on oak, remaining traces of iron may react with tannins in the wood to produce blue or black iron stain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
File (tool)
A file is a tool used to remove fine amounts of material from a workpiece. It is common in woodworking, metalworking, and other similar trade and hobby tasks. Most are hand tools, made of a case hardened steel bar of rectangular, square, triangular, or round cross-section, with one or more surfaces cut with sharp, generally parallel Tine (structural), teeth. A narrow, pointed Tang (tools), tang is common at one end, to which a handle may be fitted.. A rasp is a form of file with distinct, individually cut teeth used for coarsely removing large amounts of material. Files have also been developed with abrasive surfaces, such as natural or synthetic diamond tool, diamond grains or silicon carbide, allowing removal of material that would dull or resist steel files, such as ceramic. History Early filing or rasping has prehistoric roots and grew naturally out of the blending of the twin inspirations of cutting with stone cutting tools (such as hand axes) and abrasive, abrading u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
