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84-674: Ohara Inc. ( 株式会社オハラ , Kabushiki-gaisha Ohara ) is a Japanese global glass manufacturing company. It is headquartered in Sagamihara with subsidiaries in a number of countries, including Japan, the United States, Germany, Hong Kong, Malaysia, Taiwan, and China, with Ohara Corporation being the U.S. subsidiary of the Ohara Group. Ohara manufactures glasses since 1935, the year of its founding. Their web site lists areas of specialization, including: Among other things, Ohara

168-448: A Mohs hardness of 5.5 and a standard atomic weight of 95.95 g/mol. It has a melting point of 2,623 °C (4,753 °F), sixth highest of the naturally occurring elements; only tantalum , osmium , rhenium , tungsten , and carbon have higher melting points. It has one of the lowest coefficients of thermal expansion among commercially used metals. Molybdenum is a transition metal with an electronegativity of 2.16 on

252-663: A free metal on Earth; in its minerals, it is found only in oxidized states . The free element, a silvery metal with a grey cast, has the sixth-highest melting point of any element. It readily forms hard, stable carbides in alloys , and for this reason most of the world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys . Most molybdenum compounds have low solubility in water. Heating molybdenum-bearing minerals under oxygen and water affords molybdate ion MoO 4 , which forms quite soluble salts. Industrially, molybdenum compounds (about 14% of world production of

336-642: A froth flotation process to recover molybdenite from ores; flotation remains the primary isolation process. During World War I , demand for molybdenum spiked; it was used both in armor plating and as a substitute for tungsten in high-speed steels . Some British tanks were protected by 75 mm (3 in) manganese steel plating, but this proved to be ineffective. The manganese steel plates were replaced with much lighter 25 mm (1.0 in) molybdenum steel plates allowing for higher speed, greater maneuverability, and better protection. The Germans also used molybdenum-doped steel for heavy artillery, like in

420-429: A pterin -based molybdenum cofactor (Moco) in their active site: sulfite oxidase , xanthine oxidoreductase , aldehyde oxidase , and mitochondrial amidoxime reductase . People severely deficient in molybdenum have poorly functioning sulfite oxidase and are prone to toxic reactions to sulfites in foods. The human body contains about 0.07 mg of molybdenum per kilogram of body weight, with higher concentrations in

504-401: A bank of 5–20 identical sections, each of which contains one complete set of mechanisms to make containers. The sections are in a row, and the gobs feed into each section via a moving chute, called the gob distributor . Sections make either one, two, three or four containers simultaneously (referred to as "single", "double", "triple" and "quad" gob). In the case of multiple gobs, the "shears" cut

588-670: A commodity. The Knaben mine in southern Norway, opened in 1885, was the first dedicated molybdenum mine. Closed in 1973 but reopened in 2007, it now produces 100,000 kilograms (98 long tons; 110 short tons) of molybdenum disulfide per year. Large mines in Colorado (such as the Henderson mine and the Climax mine ) and in British Columbia yield molybdenite as their primary product, while many porphyry copper deposits such as

672-403: A day 7 days a week. This means that there is little opportunity to either increase or decrease production rates by more than a few percent. New furnaces and forming machines cost tens of millions of dollars and require at least 18 months of planning. Given this fact, and the fact that there are usually more products than machine lines, products are sold from stock. The marketing/production challenge

756-447: A flame-resistant coating for other metals. Although its melting point is 2,623 °C (4,753 °F), molybdenum rapidly oxidizes at temperatures above 760 °C (1,400 °F) making it better-suited for use in vacuum environments. TZM (Mo (~99%), Ti (~0.5%), Zr (~0.08%) and some C) is a corrosion-resisting molybdenum superalloy that resists molten fluoride salts at temperatures above 1,300 °C (2,370 °F). It has about twice

840-438: A geographical business; the product is heavy and large in volume, and the major raw materials (sand, soda ash and limestone) are generally readily available. Therefore production facilities need to be located close to their markets. A typical glass furnace holds hundreds of tonnes of molten glass, and so it is simply not practical to shut it down every night, or in fact in any period short of a month. Factories therefore run 24 hours

924-524: A greater supply of molybdenum in the soil, people living in those areas have about 16 times greater risk for esophageal squamous cell carcinoma . Molybdenum deficiency has also been reported as a consequence of non-molybdenum supplemented total parenteral nutrition (complete intravenous feeding) for long periods of time. It results in high blood levels of sulfite and urate , in much the same way as molybdenum cofactor deficiency . Since pure molybdenum deficiency from this cause occurs primarily in adults,

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1008-436: A powder or as a fine-grained material. Systems for controlling dusty materials tend to be difficult to maintain, and given the large amounts of material moved each day, only a small amount has to escape for there to be a dust problem. Cullet (broken or waste glass) is also moved about in a glass factory and tends to produce fine glass particles when shovelled or broken. Molybdenum Molybdenum does not occur naturally as

1092-413: A process of purine catabolism , is catalyzed by xanthine oxidase , a molybdenum-containing enzyme. The activity of xanthine oxidase is directly proportional to the amount of molybdenum in the body. An extremely high concentration of molybdenum reverses the trend and can inhibit purine catabolism and other processes. Molybdenum concentration also affects protein synthesis , metabolism , and growth. Mo

1176-500: A surface or as a solid lubricant. Even when molybdena was distinguishable from graphite, it was still confused with the common lead ore PbS (now called galena ); the name comes from Ancient Greek Μόλυβδος molybdos , meaning lead . (The Greek word itself has been proposed as a loanword from Anatolian Luvian and Lydian languages). Although (reportedly) molybdenum was deliberately alloyed with steel in one 14th-century Japanese sword (mfd. c.  1330 ), that art

1260-438: A variety of faults. Typical faults include small cracks in the glass called "checks" and foreign inclusions called "stones" which are pieces of the refractory brick lining of the melting furnace that break off and fall into the pool of molten glass, or more commonly oversized silica granules (sand) that have failed to melt and which subsequently are included in the final product. These are especially important to select out due to

1344-408: A variety of ways during the history of glass . Broadly, modern glass container factories are three-part operations: the "batch house", the "hot end", and the "cold end". The batch house handles the raw materials; the hot end handles the manufacture proper—the forehearth, forming machines, and annealing ovens; and the cold end handles the product-inspection and packaging equipment. Batch processing

1428-861: Is a fission product . It is a parent radioisotope to the short-lived gamma-emitting daughter radioisotope technetium-99m , a nuclear isomer used in various imaging applications in medicine. In 2008, the Delft University of Technology applied for a patent on the molybdenum-98-based production of molybdenum-99. Molybdenum forms chemical compounds in oxidation states −4 and from −2 to +6. Higher oxidation states are more relevant to its terrestrial occurrence and its biological roles, mid-level oxidation states are often associated with metal clusters , and very low oxidation states are typically associated with organomolybdenum compounds . The chemistry of molybdenum and tungsten show strong similarities. The relative rarity of molybdenum(III), for example, contrasts with

1512-492: Is a component in most nitrogenases . Among molybdoenzymes, nitrogenases are unique in lacking the molybdopterin. Nitrogenases catalyze the production of ammonia from atmospheric nitrogen: The biosynthesis of the FeMoco active site is highly complex. Molybdate is transported in the body as MoO 4 . Molybdenum is an essential trace dietary element . Four mammalian Mo-dependent enzymes are known, all of them harboring

1596-580: Is a major supplier of optical glass. Lens design programs will typically include glasses in the Ohara catalog among their stock material choices, along with, for example, glasses in the Schott catalog. On their website, Ohara describes a line of more than 130 environmentally safe glasses, produced without lead and arsenic. They produce more than 300 tons of optical glass a month (against 10800 tons/month for Schott and over 108000 tons/month for Corning). The glass

1680-399: Is also used in steel alloys for its high corrosion resistance and weldability . Molybdenum contributes corrosion resistance to type-300 stainless steels (specifically type-316) and especially so in the so-called superaustenitic stainless steels (such as alloy AL-6XN , 254SMO and 1925hMo). Molybdenum increases lattice strain, thus increasing the energy required to dissolve iron atoms from

1764-499: Is an essential element in most organisms; a 2008 research paper speculated that a scarcity of molybdenum in the Earth's early oceans may have strongly influenced the evolution of eukaryotic life (which includes all plants and animals). At least 50 molybdenum-containing enzymes have been identified, mostly in bacteria. Those enzymes include aldehyde oxidase , sulfite oxidase and xanthine oxidase . With one exception, Mo in proteins

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1848-425: Is applied either using a safe organic compound or inorganic stannic chloride . Tin based systems are not the only ones used, although the most popular. Titanium tetrachloride or organo titanates can also be used. In all cases the coating renders the surface of the glass more adhesive to the cold end coating. At the cold end a layer of typically, polyethylene wax , is applied via a water based emulsion . This makes

1932-473: Is available in a variety of forms, including strip, slab, cut blanks, and pressings. Ohara includes in its catalog the famous E6 borosilicate (similar to Corning's Pyrex), ClearCeram-Z (a vitroceramic similar to Schott's Zerodur), and two well-known low dispersion glasses: FPL51 (the UD glass used by Canon) and FPL53 showing properties close to fluorite. Ohara supplied over 23.5 tons of their E6 borosilicate glass ,

2016-402: Is believed to contain either Mo(III) or Mo(IV). By contrast Mo(VI) and Mo(IV) are complexed with molybdopterin in all other molybdenum-bearing enzymes. Molybdenum is an essential element for all higher eukaryote organisms, including humans. A species of sponge , Theonella conica , is known for hyperaccumulation of molybdenum. In its pure form, molybdenum is a silvery-grey metal with

2100-433: Is bound by molybdopterin to give the molybdenum cofactor. The only known exception is nitrogenase , which uses the FeMoco cofactor, which has the formula Fe 7 MoS 9 C. In terms of function, molybdoenzymes catalyze the oxidation and sometimes reduction of certain small molecules in the process of regulating nitrogen , sulfur , and carbon . In some animals, and in humans, the oxidation of xanthine to uric acid ,

2184-441: Is common, however the environmental impact of washing containers as against remelting them is uncertain. Factors to consider here are the chemicals and fresh water used in the washing, and the fact that a single-use container can be made much lighter, using less than half the glass (and therefore energy content) of a multiuse container. Also, a significant factor in the developed world's consideration of reuse are producer concerns over

2268-406: Is created by the forming machines. Operated by compressed air, they can produce noise levels of up to 106 dBA . How this noise is carried into the local neighborhood depends heavily on the layout of the factory. Another factor in noise production is truck movements. A typical factory will process 600 T of material a day. This means that some 600 T of raw material has to come onto the site and

2352-678: Is limited only by the quality of the furnace’s superstructure material and by the glass composition. Types of furnaces used in container glass making include "end-port" (end-fired), "side-port", and "oxy-fuel". Typically, furnace size is classified by metric tons per day (MTPD) production capability. Modern furnaces use electric heating methods that improve energy efficiency compared to traditional fossil fuel systems, contributing to reduced pollution and emissions. Electrodes made from molybdenum , graphite , or alloys are used in glass furnaces to conduct electricity and generate energy. There are currently two primary methods of making glass containers:

2436-406: Is one of the initial steps of the glass-making process. The batch house simply houses the raw materials in large silos (fed by truck or railcar), and holds anywhere from 1–5 days of material. Some batch systems include material processing such as raw material screening/sieve, drying, or pre-heating (i.e. cullet ). Whether automated or manual, the batch house measures, assembles, mixes, and delivers

2520-510: Is one step to initialize industries 2.0 in this branch. Furnaces, compressors, and forming machines generate large quantities of waste heat which are generally cooled by water. Hot glass which is not used in the forming machine is diverted and this diverted glass (called "cullet") is generally cooled by water, and sometimes even processed and crushed in a water bath arrangement. Often cooling requirements are shared over banks of cooling towers arranged to allow for backup during maintenance. After

2604-566: Is perceived as a "premium" quality packaging format. Glass containers are wholly recyclable and the glass industries in many countries have a policy, sometimes required by government regulations, of maintaining a high price on cullet to ensure high return rates. Return rates of 95% are not uncommon in the Nordic countries (Sweden, Norway, Denmark and Finland). Return rates of less than 50% are usual in other countries. Of course glass containers can also be reused , and in developing countries this

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2688-570: Is reduced by the aluminothermic reaction with addition of iron to produce ferromolybdenum . A common form of ferromolybdenum contains 60% molybdenum. Molybdenum had a value of approximately $ 30,000 per tonne as of August 2009. It maintained a price at or near $ 10,000 per tonne from 1997 through 2003, and reached a peak of $ 103,000 per tonne in June 2005. In 2008, the London Metal Exchange announced that molybdenum would be traded as

2772-418: Is referred to as a "tear". In the "press and blow" forming, if a plunger and mould are out of alignment, or heated to an incorrect temperature, the glass will stick to either item and become torn. In addition to rejecting faulty containers, inspection equipment gathers statistical information and relays it to the forming machine operators in the hot end. Computer systems collect fault information and trace it to

2856-400: Is separated at this stage by treatment with hydrogen sulfide . Ammonium molybdate converts to ammonium dimolybdate , which is isolated as a solid. Heating this solid gives molybdenum trioxide: Crude trioxide can be further purified by sublimation at 1,100 °C (2,010 °F). Metallic molybdenum is produced by reduction of the oxide with hydrogen: The molybdenum for steel production

2940-675: Is the Applied Ceramic Labelling process (ACL). This is screen-printing of the decoration onto the container with a vitreous enamel paint, which is then baked on. An example of this is the original Coca-Cola bottle. Glass containers are packaged in various ways. Popular in Europe are bulk pallets with between 1000 and 4000 containers each. This is carried out by automatic machines (palletisers) which arrange and stack containers separated by layer sheets. Other possibilities include boxes and even hand-sewn sacks. Once packed,

3024-420: Is therefore to predict demand both in the short 4- to 12-week term and over the 24- to 48-month-long term. Factories are generally sized to service the requirements of a city; in developed countries there is usually a factory per 1–2 million people. A typical factory will produce 1–3 million containers a day. Despite its positioning as a mature market product, glass does enjoy a high level of consumer acceptance and

3108-482: Is unstable. Molybdenum-98 is the most abundant isotope, comprising 24.14% of all molybdenum. Molybdenum-100 has a half-life of about 10   y and undergoes double beta decay into ruthenium-100. All unstable isotopes of molybdenum decay into isotopes of niobium , technetium , and ruthenium . Of the synthetic radioisotopes , the most stable is Mo, with a half-life of 4,839 years. The most common isotopic molybdenum application involves molybdenum-99 , which

3192-527: Is used as the valve body of torpedo engines, rocket nozzles and gas pipelines, where it can withstand extreme thermal and mechanical stresses. It is also used as radiation shields in nuclear applications. Other molybdenum-based alloys that do not contain iron have only limited applications. For example, because of its resistance to molten zinc, both pure molybdenum and molybdenum- tungsten alloys (70%/30%) are used for piping, stirrers and pump impellers that come into contact with molten zinc. Molybdenum

3276-609: Is used for the spectroscopic detection of phosphorus. The broad range of oxidation states of molybdenum is reflected in various molybdenum chlorides: The accessibility of these oxidation states depends quite strongly on the halide counterion: although molybdenum(VI) fluoride is stable, molybdenum does not form a stable hexachloride, pentabromide, or tetraiodide. Like chromium and some other transition metals, molybdenum forms quadruple bonds , such as in Mo 2 (CH 3 COO) 4 and [Mo 2 Cl 8 ] . The Lewis acid properties of

3360-1166: The Bingham Canyon Mine in Utah and the Chuquicamata mine in northern Chile produce molybdenum as a byproduct of copper-mining. About 86% of molybdenum produced is used in metallurgy , with the rest used in chemical applications. The estimated global use is structural steel 35%, stainless steel 25%, chemicals 14%, tool & high-speed steels 9%, cast iron 6%, molybdenum elemental metal 6%, and superalloys 5%. Molybdenum can withstand extreme temperatures without significantly expanding or softening, making it useful in environments of intense heat, including military armor, aircraft parts, electrical contacts, industrial motors, and supports for filaments in light bulbs . Most high-strength steel alloys (for example, 41xx steels ) contain 0.25% to 8% molybdenum. Even in these small portions, more than 43,000 tonnes of molybdenum are used each year in stainless steels , tool steels , cast irons, and high-temperature superalloys . Molybdenum

3444-493: The gob cutting shear blades . This oil-laden water mixes with the water outflow stream, thus polluting it. Factories usually have some kind of water processing equipment that removes this emulsified oil to various degrees of effectiveness. Nitrogen oxides are a natural product of the burning of gas in air and are produced in large quantities by gas-fired furnaces. Some factories in cities with particular air pollution problems will mitigate this by using liquid oxygen , however

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3528-431: The "blow and blow" method for narrow-neck containers only, and the "press and blow" method used for jars and tapered narrow-neck containers. In both methods, a stream of molten glass at its plastic temperature (1,050–1,200 °C [1,920–2,190 °F]) is cut with a shearing blade to form a solid cylinder of glass, called a "gob". The gob is of predetermined weight just sufficient to make a bottle. Both processes start with

3612-400: The "blowhead", blows the glass out, expanding into the mould, to make the final container shape. In the press and blow process, the parison is formed by a long metal plunger which rises up and presses the glass out, in order to fill the ring and blank moulds. The process then continues as before, with the parison being transferred to the final-shape mould, and the glass being blown out into

3696-509: The Earth's crust with an average of 1.5 parts per million and the 25th most abundant element in the oceans, with an average of 10 parts per billion; it is the 42nd most abundant element in the Universe. The Soviet Luna 24 mission discovered a molybdenum-bearing grain (1 × 0.6 μm) in a pyroxene fragment taken from Mare Crisium on the Moon . The comparative rarity of molybdenum in

3780-478: The Earth's crust is offset by its concentration in a number of water-insoluble ores, often combined with sulfur in the same way as copper, with which it is often found. Though molybdenum is found in such minerals as wulfenite (PbMoO 4 ) and powellite (CaMoO 4 ), the main commercial source is molybdenite (Mo S 2 ). Molybdenum is mined as a principal ore and is also recovered as a byproduct of copper and tungsten mining. The world's production of molybdenum

3864-565: The Mo cation is known to form under carefully controlled conditions. Gaseous molybdenum consists of the diatomic species Mo 2 . That molecule is a singlet , with two unpaired electrons in bonding orbitals, in addition to 5 conventional bonds. The result is a sextuple bond . There are 39 known isotopes of molybdenum, ranging in atomic mass from 81 to 119, as well as 13 metastable nuclear isomers . Seven isotopes occur naturally, with atomic masses of 92, 94, 95, 96, 97, 98, and 100. Of these naturally occurring isotopes, only molybdenum-100

3948-471: The Pauling scale. It does not visibly react with oxygen or water at room temperature, but is attacked by halogens and hydrogen peroxide. Weak oxidation of molybdenum starts at 300 °C (572 °F); bulk oxidation occurs at temperatures above 600 °C, resulting in molybdenum trioxide . Like many heavier transition metals, molybdenum shows little inclination to form a cation in aqueous solution, although

4032-466: The air used in the forming process (that is, during the final blow of the container), or through a nozzle directing a stream of the gas into the mouth of the bottle after forming. The treatment renders the container more resistant to alkali extraction, which can cause increases in product pH, and in some cases container degradation. As glass cools, it shrinks and solidifies. Uneven cooling may make glass more susceptible to fracture due to internal stresses:

4116-471: The alloys on a large scale were hampered with inconsistent results, a tendency toward brittleness, and recrystallization. In 1906, William D. Coolidge filed a patent for rendering molybdenum ductile , leading to applications as a heating element for high-temperature furnaces and as a support for tungsten-filament light bulbs; oxide formation and degradation require that molybdenum be physically sealed or held in an inert gas. In 1913, Frank E. Elmore developed

4200-484: The butyrate and perfluorobutyrate dimers, Mo 2 (O 2 CR) 4 and Rh 2 (O 2 CR) 4 , have been reported. The oxidation state 0 and lower are possible with carbon monoxide as ligand, such as in molybdenum hexacarbonyl , Mo(CO) 6 . Molybdenite —the principal ore from which molybdenum is now extracted—was previously known as molybdena. Molybdena was confused with and often utilized as though it were graphite . Like graphite, molybdenite can be used to blacken

4284-413: The details (such as cap sealing surface, screw threads, retaining rib for a tamper-proof cap, etc.) at the open end of the container. Then compressed air is blown through the glass, which results in a hollow and partly formed container. Compressed air is then blown again at the second stage to give final shape. Containers are made in two major stages. The first stage moulds all the details ("finish") around

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4368-486: The element) are used as pigments and catalysts . Molybdenum-bearing enzymes are by far the most common bacterial catalysts for breaking the chemical bond in atmospheric molecular nitrogen in the process of biological nitrogen fixation . At least 50 molybdenum enzymes are now known in bacteria, plants, and animals, although only bacterial and cyanobacterial enzymes are involved in nitrogen fixation. Most nitrogenases contain an iron–molybdenum cofactor FeMoco , which

4452-402: The fact that they can impart a destructive element to the final glass product. For example, since these materials can withstand large amounts of thermal energy, they can cause the glass product to sustain thermal shock resulting in explosive destruction when heated. Other defects include bubbles in the glass called "blisters" and excessively thin walls. Another defect common in glass manufacturing

4536-400: The forming process, some containers—particularly those intended for alcoholic spirits—undergo a treatment to improve the chemical resistance of the inside, called "internal treatment" or dealkalization . This is usually accomplished through the injection of a sulfur- or fluorine-containing gas mixture into bottles at high temperatures. The gas is typically delivered to the container either in

4620-469: The furnace, then passes to the forming process, internal treatment, and annealing. The following table lists common viscosity fixpoints, applicable to large-scale glass production and experimental glass melting in the laboratory : The batch is fed into the furnace at a slow, controlled rate by the batch processing system. The furnaces are natural gas - or fuel oil -fired, and operate at temperatures up to 1,575 °C (2,867 °F). The temperature

4704-411: The glass raw material recipe (batch) via an array of chutes, conveyors, and scales to the furnace. The batch enters the furnace at the "dog house" or "batch charger". Different glass types, colours, desired quality, raw material purity/availability, and furnace design will affect the batch recipe. The hot end of a glassworks is where the molten glass is manufactured into glass products. The batch enters

4788-507: The glass slippery, protecting it from scratching and stopping containers from sticking together when they are moved on a conveyor . The resultant invisible combined coating gives a virtually unscratchable surface to the glass. Due to reduction of in-service surface damage, the coatings often are described as strengtheners, however a more correct definition might be strength-retaining coatings. Glass containers are 100% inspected; automatic machines, or sometimes persons, inspect every container for

4872-417: The gob falling, by gravity, and guided, through troughs and chutes, into the blank moulds, two halves of which are clamped shut and then sealed by the "baffle" from above. In the "blow and blow" process, the glass is first blown through a valve in the baffle, forcing it down into the three-piece "ring mould" which is held in the "neckring arm" below the blanks, to form the "finish". The term "finish" describes

4956-401: The gobs simultaneously, and they fall into the blank moulds in parallel. Forming machines are largely powered by compressed air and a typical glass works will have several large compressors (totaling 30k–60k cfm) to provide the necessary compressed air. However in recent times servo drives have been implemented in the machines which achieve a better digital control of the forming process. It

5040-585: The liver and kidneys and lower in the vertebrae. Molybdenum is also present within human tooth enamel and may help prevent its decay. Acute toxicity has not been seen in humans, and the toxicity depends strongly on the chemical state. Studies on rats show a median lethal dose (LD 50 ) as low as 180 mg/kg for some Mo compounds. Although human toxicity data is unavailable, animal studies have shown that chronic ingestion of more than 10 mg/day of molybdenum can cause diarrhea, growth retardation, infertility , low birth weight, and gout ; it can also affect

5124-430: The logic of this given the cost in carbon of (1) not using regenerators and (2) having to liquefy and transport oxygen is highly questionable. Sulfur oxides are produced as a result of the glass melting process. Manipulating the batch formula can effect some limited mitigation of this; alternatively exhaust plume scrubbing can be used. The raw materials for glass-making are all dusty material and are delivered either as

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5208-415: The lungs, kidneys, and liver. Sodium tungstate is a competitive inhibitor of molybdenum. Dietary tungsten reduces the concentration of molybdenum in tissues. Low soil concentration of molybdenum in a geographical band from northern China to Iran results in a general dietary molybdenum deficiency and is associated with increased rates of esophageal cancer . Compared to the United States, which has

5292-412: The manufacturing process: spray on a polyethylene coating for abrasion resistance and increased lubricity, inspect the containers for defects, label the containers, and package the containers for shipment. Glass containers typically receive two surface coatings, one at the hot end , just before annealing and one at the cold end just after annealing. At the hot end a very thin layer of tin(IV) oxide

5376-453: The mineral in which it resided, and from which it might be isolated. Peter Jacob Hjelm successfully isolated molybdenum using carbon and linseed oil in 1781. For the next century, molybdenum had no industrial use. It was relatively scarce, the pure metal was difficult to extract, and the necessary techniques of metallurgy were immature. Early molybdenum steel alloys showed great promise of increased hardness, but efforts to manufacture

5460-446: The mould that produced the container. This is done by reading the mould number on the container, which is encoded (as a numeral, or a binary code of dots) on the container by the mould that made it. Operators carry out a range of checks manually on samples of containers, usually visual and dimensional checks. Sometimes container factories will offer services such as "labelling". Several labelling technologies are available. Unique to glass

5544-404: The mould. The container is then picked up from the mould by the "take-out" mechanism, and held over the "deadplate", where air cooling helps cool down the still-soft glass. Finally, the bottles are swept onto a conveyor by the "push out paddles" that have air pockets to keep the bottles standing after landing on the "deadplate"; they're now ready for annealing. The forming machines hold and move

5628-405: The new "stock units" are labelled, warehoused, and ultimately shipped. Glass container manufacture in the developed world is a mature market business. World demand for flat glass was approximately 52 million tonnes in 2009. The United States, Europe and China account for 75% of demand, with China's consumption having increased from 20% in the early 1990s to 50%. Glass container manufacture is also

5712-416: The opening, but the body of the container is initially made much smaller than its final size. These partly manufactured containers are called "parisons", and quite quickly, they are blow-molded into final shape. The "rings" are sealed from below by a short plunger. After the "settleblow" finishes, the plunger retracts slightly, to allow the skin that's formed to soften. "Counterblow" air then comes up through

5796-410: The parts that form the container. The machine consists of 19 basic mechanisms in operation to form a bottle and generally powered by compressed air (high pressure – 3.2 bar and low pressure – 2.8 bar), the mechanisms are electronically timed to coordinate all movements of the mechanisms. The most widely used forming machine arrangement is the individual section machine (or IS machine). This machine has

5880-554: The past. This method gives the sheet uniform thickness and very flat surfaces. Modern windows are made from float glass. Most float glass is soda–lime glass , but relatively minor quantities of special borosilicate and flat panel display glass are also produced using the float glass process. The float glass process is also known as the Pilkington process , named after the British glass manufacturer Pilkington , who pioneered

5964-414: The pervasiveness of the chromium(III) compounds. The highest oxidation state is seen in molybdenum(VI) oxide (MoO 3 ), whereas the normal sulfur compound is molybdenum disulfide MoS 2 . From the perspective of commerce, the most important compounds are molybdenum disulfide ( MoS 2 ) and molybdenum trioxide ( MoO 3 ). The black disulfide is the main mineral. It is roasted in air to give

6048-415: The plunger, to create the parison. The baffle rises and the blanks open. The parison is inverted in an arc to the "mould side" by the "neckring arm", which holds the parison by the "finish". As the neckring arm reaches the end of its arc, two mould halves close around the parison. The neckring arm opens slightly to release its grip on the "finish", then reverts to the blank side. "Final blow", applied through

6132-756: The purest optical glass in the world, to be cast into the blank of the primary and tertiary mirror of the Large Synoptic Survey Telescope . E6 glass was also used to manufacture the mirror of the Giant Magellan Telescope and the Large Binocular Telescope , both having a primary mirror 8.4 m wide. Glass production Glass production involves two main methods – the float glass process that produces sheet glass, and glassblowing that produces bottles and other containers. It has been done in

6216-403: The rest of Asia (mostly Armenia, Russia, Iran and Mongolia) produce the remainder. In molybdenite processing, the ore is first roasted in air at a temperature of 700 °C (1,292 °F). The process gives gaseous sulfur dioxide and the molybdenum(VI) oxide : The resulting oxide is then usually extracted with aqueous ammonia to give ammonium molybdate: Copper, an impurity in molybdenite,

6300-467: The risk and consequential product liability of using a component (the reused container) of unknown and unqualified safety. How glass containers compare to other packaging types ( plastic , cardboard , aluminium ) is hard to say; conclusive lifecycle studies are yet to be produced. Float glass is a sheet of glass made by floating molten glass on a bed of molten metal, typically tin , although lead and various low melting point alloys were used in

6384-411: The same off the site again as finished product. Water is used to cool the furnace, compressor and unused molten glass. Water use in factories varies widely; it can be as little as one tonne water used per melted tonne of glass. Of the one tonne, roughly half is evaporated to provide cooling, the rest forms a wastewater stream. Most factories use water containing an emulsified oil to cool and lubricate

6468-409: The strength of pure Mo, and is more ductile and more weldable, yet in tests it resisted corrosion of a standard eutectic salt ( FLiBe ) and salt vapors used in molten salt reactors for 1100 hours with so little corrosion that it was difficult to measure. Due to its excellent mechanical properties under high temperature and high pressure, TZM alloys are extensively applied in the military industry. It

6552-420: The super-heavy howitzer Big Bertha , because traditional steel melts at the temperatures produced by the propellant of the one ton shell. After the war, demand plummeted until metallurgical advances allowed extensive development of peacetime applications. In World War II , molybdenum again saw strategic importance as a substitute for tungsten in steel alloys. Molybdenum is the 54th most abundant element in

6636-409: The surface cools first, then as the interior cools and contracts it creates tension. Even cooling is achieved by annealing . An annealing oven (known in the industry as a lehr ) heats the container to about 580 °C (1,076 °F), then cools it, depending on the glass thickness, over a 20 – 60 minute period. The role of the cold end of glass container production is to complete the final tasks in

6720-453: The surface. Molybdenum is also used to enhance the corrosion resistance of ferritic (for example grade 444) and martensitic (for example 1.4122 and 1.4418) stainless steels. Because of its lower density and more stable price, molybdenum is sometimes used in place of tungsten. An example is the 'M' series of high-speed steels such as M2, M4 and M42 as substitution for the 'T' steel series, which contain tungsten. Molybdenum can also be used as

6804-506: The technique (invented by Sir Alastair Pilkington ) in the 1950s. As with all highly concentrated industries, glassworks suffer from moderately high local environmental impacts. Compounding this is that because they are mature market businesses, they often have been located on the same site for a long time and this has resulted in residential encroachment. The main impacts on residential housing and cities are noise, fresh water use, water pollution, NOx and SOx air pollution, and dust. Noise

6888-678: The trioxide: The trioxide, which is volatile at high temperatures, is the precursor to virtually all other Mo compounds as well as alloys. Molybdenum has several oxidation states , the most stable being +4 and +6 (bolded in the table at left). Molybdenum(VI) oxide is soluble in strong alkaline water, forming molybdates (MoO 4 ). Molybdates are weaker oxidants than chromates . They tend to form structurally complex oxyanions by condensation at lower pH values, such as [Mo 7 O 24 ] and [Mo 8 O 26 ] . Polymolybdates can incorporate other ions, forming polyoxometalates . The dark-blue phosphorus -containing heteropolymolybdate P[Mo 12 O 40 ]

6972-640: Was 250,000 tonnes in 2011, the largest producers being China (94,000 t), the United States (64,000 t), Chile (38,000 t), Peru (18,000 t) and Mexico (12,000 t). The total reserves are estimated at 10 million tonnes, and are mostly concentrated in China (4.3 Mt), the US (2.7 Mt) and Chile (1.2 Mt). By continent, 93% of world molybdenum production is about evenly shared between North America, South America (mainly in Chile), and China. Europe and

7056-482: Was never employed widely and was later lost. In the West in 1754, Bengt Andersson Qvist examined a sample of molybdenite and determined that it did not contain lead and thus was not galena. By 1778 Swedish chemist Carl Wilhelm Scheele stated firmly that molybdena was (indeed) neither galena nor graphite. Instead, Scheele correctly proposed that molybdena was an ore of a distinct new element, named molybdenum for

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