1.
Wrought iron
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Wrought iron is an iron alloy with a very low carbon content in contrast to cast iron. It is a mass of iron with fibrous slag inclusions which gives it a grain resembling wood. Wrought iron is tough, malleable, ductile, corrosion-resistant and easily welded, before the development of effective methods of steelmaking and the availability of large quantities of steel, wrought iron was the most common form of malleable iron. A wrought product is one that has been worked by forging, extruding, rolling, hammering, etcetera, to change its form. Wrought iron is a worked iron product that is seldom produced today as other cheaper. Historically, a modest amount of iron was refined into steel. The demand for wrought iron reached its peak in the 1860s with the adaptation of ironclad warships, however, as properties such as brittleness of mild steel improved, it became less costly and more widely available than wrought iron, whose usage then declined. Wrought iron is no longer produced on a commercial scale, many products described as wrought iron, such as guard rails, garden furniture and gates, are actually made of mild steel. They retain that description because they are made to resemble objects which in the past were wrought by hand by a blacksmith, the word wrought is an archaic past participle of the verb to work, and so wrought iron literally means worked iron. Wrought iron is a term for the commodity, but is also used more specifically for finished iron goods. It was used in that sense in British Customs records. Cast iron, unlike wrought iron, is brittle and cannot be worked either hot or cold, Cast iron can break if struck with a hammer. In the 17th, 18th, and 19th centuries, wrought iron went by a variety of terms according to its form, origin. While the bloomery process produced wrought iron directly from ore, cast iron or pig iron were the materials used in the finery forge. Pig iron and cast iron have higher content than wrought iron. Cast and especially pig iron have excess slag which must be at least partially removed to produce quality wrought iron, at foundries it was common to blend scrap wrought iron with cast iron to improve the physical properties of castings. Fusion eventually became accepted as relatively more important than composition below a given low carbon concentration. Another difference is that steel can be hardened by heat treating, historically, wrought iron was known as commercially pure iron, however, it no longer qualifies because current standards for commercially pure iron require a carbon content of less than 0.008 wt%
2.
Steel
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Steel is an alloy of iron and other elements, primarily carbon, that is widely used in construction and other applications because of its high tensile strength and low cost. Steels base metal is iron, which is able to take on two forms, body centered cubic and face centered cubic, depending on its temperature. It is the interaction of those allotropes with the elements, primarily carbon. In the body-centred cubic arrangement, there is an atom in the centre of each cube. Carbon, other elements, and inclusions within iron act as hardening agents that prevent the movement of dislocations that otherwise occur in the lattices of iron atoms. The carbon in steel alloys may contribute up to 2. 1% of its weight. Steels strength compared to pure iron is possible at the expense of irons ductility. With the invention of the Bessemer process in the mid-19th century and this was followed by Siemens-Martin process and then Gilchrist-Thomas process that refined the quality of steel. With their introductions, mild steel replaced wrought iron, further refinements in the process, such as basic oxygen steelmaking, largely replaced earlier methods by further lowering the cost of production and increasing the quality of the product. Today, steel is one of the most common materials in the world and it is a major component in buildings, infrastructure, tools, ships, automobiles, machines, appliances, and weapons. Modern steel is generally identified by various grades defined by assorted standards organizations, the noun steel originates from the Proto-Germanic adjective stakhlijan, which is related to stakhla. The carbon content of steel is between 0. 002% and 2. 1% by weight for plain iron–carbon alloys and these values vary depending on alloying elements such as manganese, chromium, nickel, iron, tungsten, carbon and so on. Basically, steel is an alloy that does not undergo eutectic reaction. In contrast, cast iron does undergo eutectic reaction, too little carbon content leaves iron quite soft, ductile, and weak. Carbon contents higher than those of steel make an alloy, commonly called pig iron, while iron alloyed with carbon is called carbon steel, alloy steel is steel to which other alloying elements have been intentionally added to modify the characteristics of steel. Common alloying elements include, manganese, nickel, chromium, molybdenum, boron, titanium, vanadium, tungsten, cobalt, and niobium. Additional elements are important in steel, phosphorus, sulfur, silicon, and traces of oxygen, nitrogen, and copper. Alloys with a higher than 2. 1% carbon content, depending on other element content, cast iron is not malleable even when hot, but it can be formed by casting as it has a lower melting point than steel and good castability properties
3.
Tin
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Tin is a chemical element with symbol Sn and atomic number 50. It is a metal in group 14 of the periodic table. It is obtained chiefly from the mineral cassiterite, which contains tin dioxide, Tin shows a chemical similarity to both of its neighbors in group 14, germanium and lead, and has two main oxidation states, +2 and the slightly more stable +4. Tin is the 49th most abundant element and has, with 10 stable isotopes, metallic tin is not easily oxidized in air. The first alloy used on a scale was bronze, made of tin and copper. After 600 BC, pure metallic tin was produced, pewter, which is an alloy of 85–90% tin with the remainder commonly consisting of copper, antimony, and lead, was used for flatware from the Bronze Age until the 20th century. In modern times, tin is used in alloys, most notably tin/lead soft solders. Another large application for tin is corrosion-resistant tin plating of steel, inorganic tin compounds are rather non-toxic. Because of its low toxicity, tin-plated metal was used for packaging as tin cans. However, overexposure to tin may cause problems with metabolizing essential trace elements such as copper and zinc, Tin is a soft, malleable, ductile and highly crystalline silvery-white metal. When a bar of tin is bent, a sound known as the tin cry can be heard from the twinning of the crystals. Tin melts at the low temperature of about 232 °C, the lowest in group 14, the melting point is further lowered to 177.3 °C for 11 nm particles. β-tin, which is stable at and above room temperature, is malleable, in contrast, α-tin, which is stable below 13.2 °C, is brittle. α-tin has a cubic crystal structure, similar to diamond. α-tin has no properties at all because its atoms form a covalent structure in which electrons cannot move freely. It is a dull-gray powdery material with no common uses other than a few specialized semiconductor applications and these two allotropes, α-tin and β-tin, are more commonly known as gray tin and white tin, respectively. Two more allotropes, γ and σ, exist at temperatures above 161 °C, in cold conditions, β-tin tends to transform spontaneously into α-tin, a phenomenon known as tin pest. Commercial grades of tin resist transformation because of the effect of the small amounts of bismuth, antimony, lead
4.
Solder
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Solder is a fusible metal alloy used to create a permanent bond between metal workpieces. The word solder comes from the Middle English word soudur, via Old French solduree and soulder, from the Latin solidare, meaning to make solid. In fact, solder must be melted in order to adhere to and connect the pieces together, whenever possible, the solder should also be resistant to oxidative and corrosive effects that would degrade the joint over time. Solder that is intended for use in making connections between electronic components also usually has favorable electrical characteristics. Soft solder typically has a melting point range of 90 to 450 °C, and is used in electronics, plumbing. Manual soldering uses an iron or soldering gun. Alloys that melt between 180 and 190 °C are the most commonly used, soldering performed using alloys with a melting point above 450 °C is called hard soldering, silver soldering, or brazing. In specific proportions, some alloys can become eutectic — that is, non-eutectic alloys have markedly different solidus and liquidus temperatures, and within that range they exist as a paste of solid particles in a melt of the lower-melting phase. In electrical work, if the joint is disturbed in the pasty state before it has solidified totally, for electrical and electronics work, solder wire is available in a range of thicknesses for hand-soldering, and with cores containing flux. It is also available as a paste or as a preformed foil shaped to match the workpiece, alloys of lead and tin were commonly used in the past, and are still available, they are particularly convenient for hand-soldering. Lead-free solders have been increasing in use due to regulatory requirements plus the health and they are almost exclusively used today in consumer electronics. Plumbers often use bars of solder, much thicker than the used for electrical applications. Jewelers often use solder in thin sheets, which cut into snippets. In the US, manufacturers may receive tax benefits by reducing the use of lead-based solder, lead-free solders in commercial use may contain tin, copper, silver, bismuth, indium, zinc, antimony, and traces of other metals. Most lead-free replacements for conventional 60/40 and 63/37 Sn-Pb solder have melting points from 5 to 20 °C higher and it may be desirable to use minor modification of the solder pots used in wave-soldering, to reduce maintenance cost due to increased tin-scavenging of high-tin solder. Lead-free solder may be desirable for critical applications, such as aerospace and medical projects. Tin-Silver-Copper solders are used by two-thirds of Japanese manufacturers for reflow and wave soldering, tin-based solders readily dissolve gold, forming brittle intermetallics, for Sn-Pb alloys the critical concentration of gold to embrittle the joint is about 4%. Indium-rich solders are more suitable for soldering thicker gold layer as the rate of gold in indium is much slower
5.
Rust
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Rust is an iron oxide, usually red oxide formed by the redox reaction of iron and oxygen in the presence of water or air moisture. Several forms of rust are distinguishable both visually and by spectroscopy, and form under different circumstances, Rust consists of hydrated iron oxides Fe2O3·nH2O and iron oxide-hydroxide. Given sufficient time, oxygen, and water, any iron mass will eventually convert entirely to rust, surface rust is flaky and friable, and it provides no protection to the underlying iron, unlike the formation of patina on copper surfaces. Rusting is the term for corrosion of iron and its alloys. Many other metals undergo similar corrosion, but the resulting oxides are not commonly called rust, other forms of rust exist, like the result of reactions between iron and chloride in an environment deprived of oxygen. Rebar used in concrete pillars, which generates green rust, is an example. Rust is another name for iron oxide, which occurs when iron or an alloy that contains iron, like steel, is exposed to oxygen and moisture for a long period of time. Over time, the oxygen combines with the metal at a level, forming a new compound called an oxide. Although some people refer to rust generally as oxidation, that term is more general, although rust forms when iron undergoes oxidation. Only iron or alloys that contain iron can rust, but other metals can corrode in similar ways, the main catalyst for the rusting process is water. Iron or steel structures might appear to be solid, but water molecules can penetrate the microscopic pits, the hydrogen atoms present in water molecules can combine with other elements to form acids, which will eventually cause more metal to be exposed. If chloride ions are present, as is the case with saltwater, meanwhile, the oxygen atoms combine with metallic atoms to form the destructive oxide compound. As the atoms combine, they weaken the metal, making the structure brittle, when impure iron is in contact with water, oxygen, other strong oxidants, or acids, it rusts. If salt is present, for example in seawater or salt spray, iron metal is relatively unaffected by pure water or by dry oxygen. As with other metals, like aluminium, a tightly adhering oxide coating, the conversion of the passivating ferrous oxide layer to rust results from the combined action of two agents, usually oxygen and water. Other degrading solutions are sulfur dioxide in water and carbon dioxide in water, under these corrosive conditions, iron hydroxide species are formed. Unlike ferrous oxides, the hydroxides do not adhere to the bulk metal, when iron rusts, the oxides take up more volume than the original metal, this expansion can generate enormous forces, damaging structures made with iron. See Economic effect for more details, the rusting of iron is an electrochemical process that begins with the transfer of electrons from iron to oxygen
6.
Wire
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A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads or electricity and telecommunications signals, Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Wire gauges come in standard sizes, as expressed in terms of a gauge number. The term wire is used more loosely to refer to a bundle of such strands, as in multistranded wire. Wire comes in solid core, stranded, or braided forms, edge-wound coil springs, such as the Slinky toy, are made of special flattened wire. In some cases, strips cut from metal sheet were made into wire by pulling them through perforations in stone beads and this causes the strips to fold round on themselves to form thin tubes. This strip drawing technique was in use in Egypt by the 2nd Dynasty, from the middle of the 2nd millennium BCE most of the gold wires in jewellery are characterised by seam lines that follow a spiral path along the wire. Such twisted strips can be converted into solid round wires by rolling them between flat surfaces or the wire drawing method. The strip twist wire manufacturing method was superseded by drawing in the ancient Old World sometime between about the 8th and 10th centuries AD, there is some evidence for the use of drawing further East prior to this period. Square and hexagonal wires were made using a swaging technique. In this method a metal rod was struck between grooved metal blocks, or between a punch and a grooved metal anvil. Swaging is of great antiquity, possibly dating to the beginning of the 2nd millennium BCE in Egypt and in the Bronze and Iron Ages in Europe for torcs, twisted square-section wires are a very common filigree decoration in early Etruscan jewelry. In about the middle of the 2nd millennium BCE, a new category of decorative tube was introduced which imitated a line of granules. True beaded wire, produced by mechanically distorting a round-section wire, appeared in the Eastern Mediterranean and Italy in the seventh century BCE, a forerunner to beaded wire may be the notched strips and wires which first occur from around 2000 BCE in Anatolia. Wire was drawn in England from the medieval period, the wire was used to make wool cards and pins, manufactured goods whose import was prohibited by Edward IV in 1463. The first wire mill in Great Britain was established at Tintern in about 1568 by the founders of the Company of Mineral and Battery Works, apart from their second wire mill at nearby Whitebrook, there were no other wire mills before the second half of the 17th century. Despite the existence of mills, the drawing of wire down to fine sizes continued to be done manually. Wire is usually drawn of cylindrical form, but it may be made of any desired section by varying the outline of the holes in the draw-plate through which it is passed in the process of manufacture
7.
Electrical conductor
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In physics and electrical engineering, a conductor is an object or type of material that allows the flow of an electrical current in one or more directions. Materials made of metal are common electrical conductors, Electrical current is generated by the flow of negatively charged electrons, positively charged holes, and positive or negative ions in some cases. In order for current to flow, it is not necessary for one charged particle to travel from the producing the current to that consuming it. Instead, the particle simply needs to nudge its neighbor a finite amount who will nudge its neighbor and on and on until a particle is nudged into the consumer. Essentially what is occurring here is a chain of momentum transfer between mobile charge carriers, the Drude model of conduction describes this process more rigorously. Insulators are non-conducting materials with few mobile charges that support only insignificant electric currents, the resistance of a given conductor depends on the material it is made of, and on its dimensions. For a given material, the resistance is proportional to the cross-sectional area. For example, a copper wire has lower resistance than an otherwise-identical thin copper wire. Also, for a material, the resistance is proportional to the length, for example. The resistance R and conductance G of a conductor of uniform cross section, therefore, the resistivity and conductivity are proportionality constants, and therefore depend only on the material the wire is made of, not the geometry of the wire. Resistivity and conductivity are reciprocals, ρ =1 / σ, resistivity is a measure of the materials ability to oppose electric current. This formula is not exact, It assumes the current density is uniform in the conductor. However, this still provides a good approximation for long thin conductors such as wires. Another situation this formula is not exact for is with alternating current, then, the geometrical cross-section is different from the effective cross-section in which current actually flows, so the resistance is higher than expected. Similarly, if two conductors are each other carrying AC current, their resistances increase due to the proximity effect. Aside from the geometry of the wire, temperature also has a significant effect on the efficacy of conductors, temperature affects conductors in two main ways, the first is that materials may expand under the application of heat. The amount that the material will expand is governed by the expansion coefficient specific to the material. Such an expansion will change the geometry of the conductor and therefore its characteristic resistance, however, this effect is generally small, on the order of 10−6
8.
Redox
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Redox is a chemical reaction in which the oxidation states of atoms are changed. Any such reaction involves both a process and a complementary oxidation process, two key concepts involved with electron transfer processes. Redox reactions include all chemical reactions in which atoms have their oxidation state changed, in general, the chemical species from which the electron is stripped is said to have been oxidized, while the chemical species to which the electron is added is said to have been reduced. It can be explained in terms, Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom. Reduction is the gain of electrons or a decrease in state by a molecule, atom. As an example, during the combustion of wood, oxygen from the air is reduced, the reaction can occur relatively slowly, as in the case of rust, or more quickly, as in the case of fire. Redox is a portmanteau of reduction and oxidation, the word oxidation originally implied reaction with oxygen to form an oxide, since dioxygen was historically the first recognized oxidizing agent. Later, the term was expanded to encompass oxygen-like substances that accomplished parallel chemical reactions, ultimately, the meaning was generalized to include all processes involving loss of electrons. The word reduction originally referred to the loss in weight upon heating a metallic ore such as an oxide to extract the metal. In other words, ore was reduced to metal, antoine Lavoisier showed that this loss of weight was due to the loss of oxygen as a gas. Later, scientists realized that the atom gains electrons in this process. The meaning of reduction then became generalized to all processes involving gain of electrons. Even though reduction seems counter-intuitive when speaking of the gain of electrons, it help to think of reduction as the loss of oxygen. Since electrons are charged, it is also helpful to think of this as reduction in electrical charge. The electrochemist John Bockris has used the words electronation and deelectronation to describe reduction and oxidation processes respectively when they occur at electrodes and these words are analogous to protonation and deprotonation, but they have not been widely adopted by chemists. The term hydrogenation could be used instead of reduction, since hydrogen is the agent in a large number of reactions. But, unlike oxidation, which has been generalized beyond its root element, the word redox was first used in 1928. The processes of oxidation and reduction occur simultaneously and cannot happen independently of one another, the oxidation alone and the reduction alone are each called a half-reaction, because two half-reactions always occur together to form a whole reaction
9.
Wire connector
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An electrical connector, is an electro-mechanical device used to join electrical terminations and create an electrical circuit. Electrical connectors consist of plugs and jacks, the connection may be temporary, as for portable equipment, require a tool for assembly and removal, or serve as a permanent electrical joint between two wires or devices. An adapter can be used to bring together dissimilar connectors. There are hundreds of types of electrical connectors, connectors may join two lengths of flexible copper wire or cable, or connect a wire or cable to an electrical terminal. In computing, a connector can also be known as a physical interface. Cable glands, known as cable connectors in the US, connect wires to devices rather than electrically and are distinct from quick-disconnects performing the latter. It is usually desirable for a connector to be easy to visually, rapid to assemble, require only simple tooling. In some cases an equipment manufacturer might choose a connector specifically because it is not compatible with those other sources. No single connector has all the properties, the proliferation of types is a reflection of differing requirements. Fretting is a failure mode in electrical connectors that have not been specifically designed to prevent it. Many connectors are keyed, with some mechanical component which prevents mating except with a correctly oriented matching connector, some connector housings are designed with locking mechanisms to prevent inadvertent disconnection or poor environmental sealing. Locking mechanism designs include locking levers of various sorts, screw locking, a terminal is a simple type of electrical connector that connects two or more wires to a single connection point. Wire nuts are another type of single point connector, terminal blocks provide a convenient means of connecting individual electrical wires without a splice or physically joining the ends. They are usually used to connect wiring among various items of equipment within an enclosure or to make connections among individually enclosed items. Since terminal blocks are available for a wide range of wire sizes and terminal quantity. One type of terminal block accepts wires that are prepared only by removing a short length of insulation from the end, another type accepts wires that have ring or spade terminal lugs crimped onto the wires. Printed circuit board mounted terminal blocks allow individual wires to be connected to the circuit board, a general type of connector that simply screws or clamps bare wire to a post, such connectors are frequently used in electronic test equipment and audio. Many, but not all binding posts will also accept a banana connector plug, since stripping the insulation from wires is time-consuming, many connectors intended for rapid assembly use insulation-displacement connectors so that insulation need not be removed from the wire
10.
Twist-on wire connector
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Twist-on wire connectors are a type of electrical connector used to fasten two or more low-voltage electrical conductors. They are widely used in North America, twist-on connectors are also known as wire nuts, wire connectors, cone connectors, or thimble connectors. One trade name for such connectors, Marrette, is derived from the name of their inventor, in the UK, items similar to those used in North America, but made from ceramic materials, were sold under the brand Scruit. Such ceramic connectors are currently sold in South Africa under the name Porcelain Scruits, twist-on wire connectors are available in a variety of sizes and shapes. While their exterior covering is made from insulating plastic, their means of connection is a tapered coiled metal insert. When such a connector is twisted onto the stripped and twisted-together ends of wires, Electrical continuity is maintained by both the direct twisted wire-to-wire contact and by contact with the metal insert. Twist-on wire connectors are typically installed by hand and they may have external grooves to make them easier to handle and apply. Winglike extensions are commonly molded into higher quality connectors to reduce muscle fatigue when installing a large number of the connectors. Such extensions also allow these connectors to be installed with a common nut driver or a specialized tool, twist-on wire connectors are commonly color-coded to indicate the connector size and, hence, their capacity. Twist-on connectors are not often used on wire gauges thicker than AWG #10, instead, set screw connectors, clamps or crimp connectors are used. Ceramic twist-on connectors are made for applications, such as heating appliances. Ordinary twist-on connectors are not rated for wet use, special gel-filled connectors must be used in this circumstance. Twist-on wire connectors are not generally recommended for use with aluminum wire, the US Consumer Product Safety Commission does not approve of their use with aluminum wire, and approves of only two methods of connection. In spite of this, several companies manufacture twist-on connectors which they claim are designed specifically for, special feedthrough twist-on wire connectors differ from standard wire connectors in that they have an additional opening at the top of the insulated cap. This allows a single-conductor bare wire to be pushed through the hole and these feedthrough connectors are typically green, and are also called screw-on grounding connectors. Another specialized connector version has an attached wire pigtail protruding from the top of the insulated cap. The pigtail may be unterminated, or it may end in a preinstalled spade lug, if colored white, it typically may be used for splicing neutral wires in a device box, while leaving a pigtail free for connection to a device. If colored green, the assembly is intended to be used as a grounding pigtail, william P. Marr emigrated from Scotland to Ontario, Canada early in the twentieth century
11.
Binding post
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A binding post is a connector commonly used on electronic test equipment to terminate a single wire or test lead. They are also found on loudspeakers and audio amplifiers as well as electrical equipment. A binding post contains a central threaded metal rod and a cap that screws down on that rod. The cap is commonly insulated with plastic and color-coded, red commonly means an active or positive terminal, black indicates an inactive or negative terminal, bare wire inserted through the same hole and clamped, or Wrapped around the metal post and clamped. A lug terminal, with a 1/4-inch inner diameter, inserted around the metal post, the binding post was a commercial invention of the General Radio Corporation. Even so-called isolated binding posts are not sufficiently isolated to protect users from coming into contact with their metal parts carrying voltage. As such they are not suitable to be used for carrying dangerous voltages, on several types of equipment it has been becoming common to no longer use the traditional binding posts, but safety banana jacks. The universal property of binding posts is lost here, since safety banana jacks can only be used with traditional and safety banana plugs. But this also impaired safety as two wires or pin connectors could be inserted from opposite sides of two binding posts and the tips of the wires or probes might inadvertently short together, holes are now normally aligned in such a fashion that such shorts cannot occur. In order to permit the use of double banana plugs, the distance between the positive and negative plugs should be 3/4 inch, fahnestock clip — an earlier device, now largely supplanted by binding posts Banana connector About. com glossary definition
12.
Terminal block
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A screw terminal is a type of electrical connector where a wire is held by the tightening of a screw. The wire may be stripped of insulation and inserted under the head of a screw or into the terminal. Otherwise, it may be either inserted first into a ferrule, depending on the design, a flat-blade screwdriver, a cross-blade screwdriver, hex key, Torx key, or other tool may be required to properly tighten the connection for reliable operation. Screw terminals are used to connect a chassis ground, such as on a record player or surge protector. Most public address systems in buildings also use them for speakers, alarm systems and building sensor and control systems have traditionally used large numbers of screw terminations. Grounding screws are often color-coded green and, when used on consumer electronics and these are known as connector strips or chocolate blocks in the UK. These are often used to light fixtures and are shown at the right. Alternatively, terminals can also be arranged as a strip or terminal block. This creates a bus bar for power distribution, and so may include a master input connector. Assembly of a screw connection requires some care in workmanship to ensure removal of insulation, containment of all wire strands. If the wire diameter is small in relation to the size of the screw and this is less likely to occur when a wire is clamped between two plates by the action of a screw. Screw connectors sometimes come loose if not done up tightly enough at fitting time, verifying adequate tightening torque requires calibrated installation tools and proper training. In the UK, all screw connectors on fixed mains installations are required to be accessible for servicing, the terminals easily can be re-used in the field, allowing for the replacement of wires or equipment, generally with standard hand tools. Screw terminals usually avoid the requirement for a mating connector to be applied to the ends of wires. When properly tightened, the connections are physically and electrically secure because they firmly contact a large section of wire, the terminals are relatively low cost compared with other types of connector, and a screw terminal can easily be integrated into the design of a building wiring device. This procedure is time consuming than using a plug-in connector - thus making screw connections uncommon for portable equipment. The screw mechanism limits the physical size of a terminal. It is difficult to automate multiple terminations with screw connections, vibration or corrosion can cause a screw connection to deteriorate over time
13.
Short circuit
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A short circuit is an electrical circuit that allows a current to travel along an unintended path with no or a very low electrical impedance. The electrical opposite of a circuit is an open circuit. It is common to misuse short circuit to describe any electrical malfunction, a short circuit is an abnormal connection between two nodes of an electric circuit intended to be at different voltages. This results in an electric current limited only by the Thévenin equivalent resistance of the rest of the network and potentially causes circuit damage, overheating. Although usually the result of a fault, there are cases where short circuits are caused intentionally, for example, in circuit analysis, a short circuit is a connection between two nodes that forces them to be at the same voltage. In an ideal circuit, this means there is no resistance. In real circuits, the result is a connection with almost no resistance, in such a case, the current is limited by the rest of the circuit. A common type of short circuit occurs when the positive and negative terminals of a battery are connected with a low-resistance conductor, with low resistance in the connection, a high current exists, causing the cell to deliver a large amount of energy in a short time. Overloaded wires can also overheat, sometimes causing damage to the wires insulation, in mains circuits, short circuits may occur between two phases, between a phase and neutral or between a phase and earth. Such short circuits are likely to result in a high current. However, it is possible for circuits to arise between neutral and earth conductors, and between two conductors of the same phase. Such short circuits can be dangerous, particularly as they may not immediately result in a current and are therefore less likely to be detected. Possible effects include unexpected energisation of a circuit presumed to be isolated, to help reduce the negative effects of short circuits, power distribution transformers are deliberately designed to have a certain amount of leakage reactance. The leakage reactance helps limit both the magnitude and rate of rise of the fault current, a short circuit may lead to formation of an electric arc. The arc, a channel of hot ionized plasma, is highly conductive, surface erosion is a typical sign of electric arc damage. Even short arcs can remove significant amount of materials from the electrodes, a short circuit fault current can, within milliseconds, be thousands of times larger than the normal operating current of the system. Damage from short circuits can be reduced or prevented by employing fuses, circuit breakers, or other overload protection, overload protection must be chosen according to the current rating of the circuit. Circuits for large home appliances require protective devices set or rated for higher currents than lighting circuits, wire gauges specified in building and electrical codes are chosen to ensure safe operation in conjunction with the overload protection
14.
Tin can
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A tin can, tin, steel can, steel packaging or a can, is a container for the distribution or storage of goods, composed of thin metal. Many cans require opening by cutting the end open, others have removable covers, cans hold diverse contents, foods, beverages, oil, chemicals, etc. Steel cans are made of tinplate or of tin-free steel, in some locations, even aluminum cans are called tin cans. The tin canning process was created by Frenchman Philippe de Girard. The canning concept was based on food preservation work in glass containers the year before by the French inventor Nicholas Appert. By 1813 they were producing their first tin canned goods for the Royal Navy, early tin cans were sealed by soldering with a tin-lead alloy, which could lead to lead poisoning. Infamously, in the 1845 Arctic expedition of Sir John Franklin, crew members suffered from lead poisoning. More recent research suggests the lead poisoning was likely to have been caused by the water pipe system on the two ships. In 1901 in the United States, the American Can Company was founded, most cans are right circular cylinders with identical and parallel round tops and bottoms with vertical sides. However, where the volume to be contained and/or the shape of the contents suggests it. Other contents may justify a can that is somewhat conical in shape. The fabrication of most cans results in at least one rim, such cans have a single rim at the top. Some cans have a cover that slides onto the top or sometimes is hinged. Two piece steel cans can be made by drawing to form the bottom and sides and adding an end at the top, cans can be fabricated with separate slip-on, or friction fit covers and with covers attached by hinges. Various easy opening methods are available, concern arose that the milk contained unsafe levels of lead leached from this solder plug. Depending on the contents and available coatings, in some locations any metal can, even aluminium, might be called a tin can. Use of aluminium in cans began in 1957, a can usually has a printed paper or plastic label glued to the outside of the curved surface, indicating its contents. Some labels contain additional information, such as recipes, on the reverse side, a label can also be printed directly onto the metal
15.
Holloware
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Holloware is constructed to last a long time. It differs from some other silverplated items in being made with thicker walls, dining car holloware is a type of railroad collectible. The relative value of pieces depends on their scarcity, age and condition, holloware is the traditional gift in the UK and the modern gift in the US for the 16th wedding anniversary. Holloware is the gift for jubilee or wedding in Russia
16.
Tinware
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Tinware is any item made of prefabricated tinplate. Usually tinware refers to kitchenware made of tinplate, often crafted by tinsmiths, many cans used for canned food are tinware as well. Something that is tinned after being shaped and fabricated is not considered tinware, tinware is strong, easily shaped, solder able, and is non-toxic. In addition, it has an appearance which can be further enhanced by lacquering it. Of extreme importance is its property of corrosion resistance, especially against attack by food products and these properties are due to the properties of tinplate, as tinware is made of tinplate. Tinplate originated in Bohemia in the Middle Ages, sources differ as to when this happened, ranging from the late thirteenth century to the fourteenth century. The technique for how to make tinplate spread to regions of Germany. Tinsmiths throughout Europe were dependent on German suppliers of tinplate, and this caused many European nations, including Great Britain, to attempt to start tinplate manufacturing industries. Successful creation of a non-German tinplate industry was hampered by technical difficulties and the cheapness of German tinplate. Tinplate became a British dominated industry until 1890, with an output exceeding 13 million boxes of plate and this may help explain why the United States passed the McKinley Tariff bill, which placed a tariff of 2.2 cents per pound on tinplate. After this tariff, and with other causes, the US tinplate industry became the largest in the world, tinware production in the United States is widely acclaimed to have started when a Scottish immigrant named Edward Pattison settled in Berlin, Hartford Country, Connecticut. During the Industrial Revolution, many turned their attention to tinware. A good example of this is the invention of the circular shears by Calvin Whiting in 1804, tinware was often sold by traveling salesmen called Yankee Peddlers. These Yankee Peddlers were both employees of tinware shops and independent, often, tinware was traded for “Truck”, or bartered items, which were sold at the tinware shop. In fact, it was preferable for Yankee Peddlers to get truck, as written by Harvey Filley in 1822, “I don’t take but a little cash when I can get truck. Most all the truck is in demand, more can be made by having quantities and knowing the market. ”Most kitchenware items that are made of aluminum and plastic in the 20th and its uses range from ale tasters and coffee pots to cookie cutters and boxes. There is an advertisement for tinware posted by Thomas Passmore on November 30,1793 in the Federal Gazette that is unique because of the arrangement of his tinware goods. 19 letters of the alphabet are represented in this list, showcasing the variety of tinware goods
17.
Bessemer process
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The Bessemer process was the first inexpensive industrial process for the mass-production of steel from molten pig iron before the development of the open hearth furnace. The key principle is removal of impurities from the iron by oxidation with air being blown through the molten iron, the oxidation also raises the temperature of the iron mass and keeps it molten. Related decarburizing with air processes had been used outside Europe for hundreds of years, one such process has existed since the 11th century in East Asia, where the scholar Shen Kuo describes its use in the Chinese iron and steel industry. In the 17th century, accounts by European travelers detailed its possible use by the Japanese, the modern process is named after its inventor, the Englishman Henry Bessemer, who took out a patent on the process in 1856. The process was said to be discovered in 1851 by the American inventor William Kelly. The process using a basic refractory lining is known as the basic Bessemer process or Gilchrist–Thomas process after the English discoverers Percy Gilchrist and these oxides either escape as gas or form a solid slag. The refractory lining of the converter also plays a role in the conversion — clay linings are used there is little phosphorus in the raw material - this is known as the acid Bessemer process. When the phosphorus content is high, dolomite, or sometimes magnesite and these are also known as Gilchrist-Thomas converters, after their inventor, Sidney Gilchrist Thomas. In order to produce steel with desired properties, additives such as spiegeleisen, when the required steel had been formed, it was poured into ladles and then transferred into moulds while the lighter slag was left behind. The conversion process, called the blow, was completed in approximately 20 minutes, during this period the progress of the oxidation of the impurities was judged by the appearance of the flame issuing from the mouth of the converter. The modern use of methods of recording the characteristics of the flame greatly aided the blower in controlling final product quality. After the blow, the metal was recarburized to the desired point and other alloying materials were added. A Bessemer converter could treat a heat of 5 to 30 tons at a time and they were usually operated in pairs, one being blown while another was being filled or tapped. Before the Bessemer process, Western Europe and the United States relied on the process to reduce the carbon content of white cast iron. It was possible to make low-quality puddled steel, but the process was difficult to control, high-quality steel was made by the reverse process of adding carbon to carbon-free wrought iron, usually imported from Sweden. The manufacturing process, called the process, consisted of heating bars of wrought iron together with charcoal for periods of up to a week in a long stone box. The blister steel was put in a crucible with wrought iron and melted, up to 3 tons of expensive coke was burnt for each ton of steel produced. Such steel when rolled into bars was sold at £50 to £60 a long ton, the most difficult and work-intensive part of the process, however, was the production of wrought iron done in finery forges in Sweden
18.
Coke (fuel)
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Coke is a fuel with few impurities and a high carbon content, usually made from coal. It is the carbonaceous material derived from destructive distillation of low-ash. Cokes made from coal are grey, hard, and porous, while coke can be formed naturally, the commonly used form is man-made. The form known as coke, or pet coke, is derived from oil refinery coker units or other cracking processes. Coke is used in preparation of producer gas which is a mixture of carbon monoxide, producer gas is produced by passing air over red-hot coke. Coke is also used to water gas. Historical sources dating to the 4th century describe the production of coke in ancient China, the Chinese first used coke for heating and cooking no later than the ninth century. By the first decades of the century, Chinese ironworkers in the Yellow River valley began to fuel their furnaces with coke. In 1589 a patent was granted to Thomas Proctor and William Peterson for making iron and steel and melting lead with earth-coal, sea-coal, turf, the patent contains a distinct allusion to the preparation of coal by cooking. In 1590 a patent was granted to the Dean of York to purify pit-coal, in 1620 a patent was granted to a company composed of William St. John, Robert Follensbee and other knights, mentioning the use of coke in smelting ores and manufacturing metals. In 1627 a patent was granted to Sir John Hacket and Octavius de Strada for a method of rendering sea-coal and pit-coal as useful as charcoal for burning in houses, without offense by smell or smoke. In 1603 Hugh Plat suggested that coal might be charred in an analogous to the way charcoal is produced from wood. In 1709 Abraham Darby I established a coke-fired blast furnace to produce cast iron, cokes superior crushing strength allowed blast furnaces to become taller and larger. The ensuing availability of iron was one of the factors leading to the Industrial Revolution. Before this time, iron-making used large quantities of charcoal, produced by burning wood, in the late 18th century, brick beehive ovens were developed, which allowed more control over the burning process. In 1768 John Wilkinson built a more practical oven for converting coal into coke, with greater skill in the firing, covering and quenching of the heaps, yields were increased from about 33 per cent to 65 per cent by the middle of the 19th century. The Scottish iron industry expanded rapidly in the second quarter of the 19th century. In 1802 a battery of beehives was set up near Sheffield, by 1870, there were 14,000 beehive ovens in operation on the West Durham coalfields, capable of producing 4.2 million tons of coke
19.
Meat
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Meat is animal flesh that is eaten as food. Humans have hunted and killed animals for meat since prehistoric times, the advent of civilization allowed the domestication of animals such as chickens, sheep, pigs and cattle. This eventually led to their use in production on an industrial scale with the aid of slaughterhouses. Meat is mainly composed of water, protein, and fat and it is edible raw, but is normally eaten after it has been cooked and seasoned or processed in a variety of ways. Unprocessed meat will spoil or rot within hours or days as a result of infection with and decomposition by bacteria, most often, meat refers to skeletal muscle and associated fat and other tissues, but it may also describe other edible tissues such as offal. The word meat comes from the Old English word mete, which referred to food in general, the term is related to mad in Danish, mat in Swedish and Norwegian, and matur in Icelandic and Faroese, which also mean food. The word mete also exists in Old Frisian to denote important food, differentiating it from swiets, paleontological evidence suggests that meat constituted a substantial proportion of the diet of even the earliest humans. Early hunter-gatherers depended on the hunting of large animals such as bison. Several breeds of sheep were established in ancient Mesopotamia and Egypt by 3500–3000 BC, today, more than 200 sheep-breeds exist. Cattle were domesticated in Mesopotamia after settled agriculture was established about 5000 BC, modern domesticated cattle fall into the groups Bos taurus and Bos indicus, both descended from the now-extinct aurochs. The breeding of cattle, cattle optimized for meat production as opposed to animals best suited for draught or dairy purposes. Domestic pigs, which are descended from boars, are known to have existed about 2500 BC in modern-day Hungary and in Troy, earlier pottery from Jericho. Pork sausages and hams were of commercial importance in Greco-Roman times. Pigs continue to be bred intensively as they are being optimized to produce meat best suited for meat products. Other animals are or have raised or hunted for their flesh. The type of meat consumed varies much between different cultures, changes over time, depending on such as tradition and the availability of the animals. The amount and kind of meat consumed also varies by income, horses are commonly eaten in France, Italy, Germany and Japan, among other countries. Horses and other mammals such as reindeer were hunted during the late Paleolithic in western Europe
20.
Fish
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A fish is any member of a group of animals that consist of all gill-bearing aquatic craniate animals that lack limbs with digits. They form a group to the tunicates, together forming the olfactores. Included in this definition are the living hagfish, lampreys, and cartilaginous, tetrapods emerged within lobe-finned fishes, so cladistically they are fish as well. However, traditionally fish are rendered obsolete or paraphyletic by excluding the tetrapods, because in this manner the term fish is defined negatively as a paraphyletic group, it is not considered a formal taxonomic grouping in systematic biology. The traditional term pisces is considered a typological, but not a phylogenetic classification, the earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts, fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators, the first fish with jaws appeared in the Silurian period, after which many became formidable marine predators rather than just the prey of arthropods. Fish are abundant in most bodies of water and they can be found in nearly all aquatic environments, from high mountain streams to the abyssal and even hadal depths of the deepest oceans. With 33,100 described species, fish exhibit greater species diversity than any group of vertebrates. Fish are an important resource for humans worldwide, especially as food, commercial and subsistence fishers hunt fish in wild fisheries or farm them in ponds or in cages in the ocean. They are also caught by fishers, kept as pets, raised by fishkeepers. Fish have had a role in culture through the ages, serving as deities, religious symbols, fish do not represent a monophyletic group, and therefore the evolution of fish is not studied as a single event. Early fish from the record are represented by a group of small, jawless. Jawless fish lineages are mostly extinct, an extant clade, the lampreys may approximate ancient pre-jawed fish. The first jaws are found in Placodermi fossils, the diversity of jawed vertebrates may indicate the evolutionary advantage of a jawed mouth. It is unclear if the advantage of a hinged jaw is greater biting force, improved respiration, fish may have evolved from a creature similar to a coral-like sea squirt, whose larvae resemble primitive fish in important ways. The first ancestors of fish may have kept the form into adulthood. Fish are a group, that is, any clade containing all fish also contains the tetrapods
21.
Fruit
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In botany, a fruit is the seed-bearing structure in flowering plants formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate seeds, accordingly, fruits account for a substantial fraction of the worlds agricultural output, and some have acquired extensive cultural and symbolic meanings. On the other hand, in usage, fruit includes many structures that are not commonly called fruits, such as bean pods, corn kernels, tomatoes. The section of a fungus that produces spores is called a fruiting body. Many common terms for seeds and fruit do not correspond to the botanical classifications, however, in botany, a fruit is the ripened ovary or carpel that contains seeds, a nut is a type of fruit and not a seed, and a seed is a ripened ovule. Examples of culinary vegetables and nuts that are botanically fruit include corn, cucurbits, eggplant, legumes, sweet pepper, in addition, some spices, such as allspice and chili pepper, are fruits, botanically speaking. g. Botanically, a grain, such as corn, rice, or wheat, is also a kind of fruit. However, the wall is very thin and is fused to the seed coat. The outer, often edible layer, is the pericarp, formed from the ovary and surrounding the seeds, the pericarp may be described in three layers from outer to inner, the epicarp, mesocarp and endocarp. Fruit that bears a prominent pointed terminal projection is said to be beaked, a fruit results from maturation of one or more flowers, and the gynoecium of the flower forms all or part of the fruit. Inside the ovary/ovaries are one or more ovules where the megagametophyte contains the egg cell, after double fertilization, these ovules will become seeds. The ovules are fertilized in a process starts with pollination. After pollination, a tube grows from the pollen through the stigma into the ovary to the ovule, later the zygote will give rise to the embryo of the seed, and the endosperm mother cell will give rise to endosperm, a nutritive tissue used by the embryo. As the ovules develop into seeds, the ovary begins to ripen and the ovary wall, in some multiseeded fruits, the extent to which the flesh develops is proportional to the number of fertilized ovules. The pericarp is often differentiated into two or three distinct layers called the exocarp, mesocarp, and endocarp, in some fruits, especially simple fruits derived from an inferior ovary, other parts of the flower, fuse with the ovary and ripen with it. In other cases, the sepals, petals and/or stamens and style of the fall off. When such other floral parts are a significant part of the fruit, it is called an accessory fruit, since other parts of the flower may contribute to the structure of the fruit, it is important to study flower structure to understand how a particular fruit forms. There are three modes of fruit development, Apocarpous fruits develop from a single flower having one or more separate carpels
22.
Biscuit
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Biscuit is a term used for a diverse variety of baked, commonly flour-based food products. The term is applied to two products in North America and the Commonwealth of Nations and Europe. The North American biscuit is typically a soft, leavened quick bread and this article covers the other type of biscuit, which is typically hard, flat and unleavened. In Commonwealth English and Hiberno-English, a biscuit is a baked product that would be called either a cookie or a cracker in the United States. Biscuits in the United Kingdom, the Isle of Man and Ireland are hard and may be savoury or sweet, such as biscuits, digestives, hobnobs, ginger nuts, rich tea, bourbons. In the Commonwealth Nations and Ireland, the term typically refers to only one type of biscuit, however. In the United States and some parts of English Canada, a biscuit is a bread, somewhat similar to a scone. Leavening is achieved through the use of baking powder or when using buttermilk baking soda, biscuits are usually referred to as either baking powder biscuits or buttermilk biscuits if buttermilk is used rather than milk as a liquid. A Southern regional variation using the term beaten biscuit is closer to hardtack than soft dough biscuits, the Old French word bescuit is derived from the Latin words bis and coquere, coctus, and, hence, means twice-cooked. This is because biscuits were originally cooked in a process, first baked. This term was adapted into English in the 14th century during the Middle Ages, in the Middle English word bisquite, to represent a hard. The Dutch language from around 1703 had adopted the word koekje to have a meaning for a similar hard. When continental Europeans began to emigrate to colonial North America, the two words and their same but different meanings began to clash, the words cookie or cracker became the words of choice to mean a hard, baked product. Further confusion has been added by the adoption of the word biscuit for a small leavened bread popular in the United States, according to the American English dictionary Merriam-Webster, a cookie is a small flat or slightly raised cake. In modern Italian usage, the term biscotto is used to refer to any type of hard twice-baked biscuit, and not only to the cantuccini as in the past. The need for nutritious, easy-to-store, easy-to-carry, and long-lasting foods on long journeys, however, this took up additional space on what were either horse-powered treks or small ships, reducing the time of travel before additional food was required. This resulted in early armies adopting the style of hunter-foraging, the introduction of the baking of processed cereals including the creation of flour provided a more reliable source of food. Egyptian sailors carried a flat, brittle loaf of bread called dhourra cake while the Romans had a biscuit called buccellum
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This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Tin-plate and Terne-plate". Encyclopædia Britannica. 26 (11th ed.). Cambridge University Press.
This article incorporates text from a publication now in the