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30-597: [REDACTED] Look up pandy in Wiktionary, the free dictionary. A pandy is a Welsh name for a fulling mill , and may refer to: Places in Wales [ edit ] Pandy, Bryn-crug, a location in Gwynedd Pandy, Dolgellau, a location in Gwynedd Pandy, Llanuwchllyn, a location in Gwynedd Pandy, Conwy, an electoral ward near Llanfairfechan , Conwy Pandy Tudur ,

60-404: A nitrogen source often must invest into more extensive root systems due to ammonium's limited mobility in soils compared to other nitrogen sources. Ammonium deposition from the atmosphere has increased in recent years due to volatilization from livestock waste and increased fertilizer use. Because net primary production is often limited by nitrogen , increased ammonium levels could impact

90-661: A British children's television series Pandya dynasty , ancient Indian dynasty of southern India Pandya (surname) , Indian surname Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Pandy . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Pandy&oldid=1214173511 " Categories : Disambiguation pages Place name disambiguation pages Disambiguation pages with surname-holder lists Hidden categories: Short description

120-437: A brown color precipitate known as the iodide of Million's base in basic medium. Ammonium ion when added to chloroplatinic acid gives a yellow precipitate of ammonium hexachloroplatinate(IV) . Ammonium ion when added to sodium cobaltinitrite gives a yellow precipitate of ammonium cobaltinitrite. Ammonium ion gives a white precipitate of ammonium bitartrate when added to potassium bitartrate . The lone electron pair on

150-431: A fulling mill is pandy , which appears in many place-names, for example Tonypandy ("fulling mill lea"). Ammonium Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged ( cationic ) molecular ion with the chemical formula NH + 4 or [NH 4 ] . It is formed by the addition of a proton (a hydrogen nucleus) to ammonia ( NH 3 ). Ammonium

180-515: A proton from the ammonium ion, generating ammonia. Formation of ammonium compounds can also occur in the vapor phase; for example, when ammonia vapor comes in contact with hydrogen chloride vapor, a white cloud of ammonium chloride forms, which eventually settles out as a solid in a thin white layer on surfaces. Ammonium cation is found in a variety of salts such as ammonium carbonate , ammonium chloride , and ammonium nitrate . Most simple ammonium salts are very soluble in water. An exception

210-408: A tiny amount of it converts to ammonium ions: The degree to which ammonia forms the ammonium ion depends on the pH of the solution. If the pH is low, the equilibrium shifts to the right: more ammonia molecules are converted into ammonium ions. If the pH is high (the concentration of hydrogen ions is low and hydroxide ions is high), the equilibrium shifts to the left: the hydroxide ion abstracts

240-584: A village in Conwy Pandy, Monmouthshire , a village near Abergavenny Pandy, Powys , a village in Powys Pandy, Ceiriog Valley , a village between Glyn Ceiriog and Llanarmon Dyffryn Ceiriog Pandy, Gwersyllt , a village near Gresford and Wrexham Pandy, Hanmer, a hamlet near Halghton, English Maelor, Wrexham Other uses [ edit ] András Pándy (1927–2013), Belgian-Hungarian serial killer See also [ edit ] Andy Pandy ,

270-492: A way for living organisms to access nitrogen for growth in a process known as assimilatory nitrate reduction. Once assimilated, it can be incorporated into proteins and DNA . Ammonium can accumulate in soils where nitrification is slow or inhibited, which is common in hypoxic soils. For example, ammonium mobilization is one of the key factors for the symbiotic association between plants and fungi, called mycorrhizae . However, plants that consistently utilize ammonium as

300-466: Is ammonium hexachloroplatinate , the formation of which was once used as a test for ammonium. The ammonium salts of nitrate and especially perchlorate are highly explosive, in these cases, ammonium is the reducing agent. In an unusual process, ammonium ions form an amalgam . Such species are prepared by the addition of sodium amalgam to a solution of ammonium chloride. This amalgam eventually decomposes to release ammonia and hydrogen. To find whether

330-448: Is also a general name for positively charged (protonated) substituted amines and quaternary ammonium cations ( [NR 4 ] ), where one or more hydrogen atoms are replaced by organic or other groups (indicated by R). Not only is ammonium a source of nitrogen and a key metabolite for many living organisms, but it is an integral part of the global nitrogen cycle . As such, human impact in recent years could have an effect on

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360-640: Is available for nitrification by microbes varies depending on environmental conditions. For example, ammonium is deposited as a waste product from some animals, although it is converted into urea in mammals, sharks, and amphibians, and into uric acid in birds, reptiles, and terrestrial snails. Its availability in soils is also influenced by mineralization , which makes more ammonium available from organic nitrogen sources, and immobilization , which sequesters ammonium into organic nitrogen sources, both of which are mitigated by biological factors. Conversely, nitrate and nitrite can be reduced to ammonium as

390-576: Is different from Wikidata All article disambiguation pages All disambiguation pages Fulling mill Waulking could be done with the hands and feet. In medieval Europe, it was done in water-powered fulling mills. After the Industrial Revolution , coal and electric power were used. Felting refers more generally to the interlocking of loose wool fibers; they need not be spun and woven first. Fulling involves two processes: scouring (cleaning) and milling (thickening). Removing

420-408: Is that between dimethylamine , (CH 3 ) 2 NH , and an acid to give the dimethylammonium cation, [(CH 3 ) 2 NH 2 ] : Quaternary ammonium cations have four organic groups attached to the nitrogen atom, they lack a hydrogen atom bonded to the nitrogen atom. These cations, such as the tetra- n -butylammonium cation, are sometimes used to replace sodium or potassium ions to increase

450-482: The nitrogen atom (N) in ammonia, represented as a line above the N, forms a coordinate bond with a proton ( H ). After that, all four N−H bonds are equivalent, being polar covalent bonds . The ion has a tetrahedral structure and is isoelectronic with methane and the borohydride anion. In terms of size, the ammonium cation ( r ionic  = 175 pm) resembles the caesium cation ( r ionic  = 183 pm). The hydrogen atoms in

480-500: The solubility of the associated anion in organic solvents . Primary, secondary, and tertiary ammonium salts serve the same function but are less lipophilic . They are also used as phase-transfer catalysts and surfactants . An unusual class of organic ammonium salts is derivatives of amine radical cations, [•NR 3 ] such as tris(4-bromophenyl)ammoniumyl hexachloroantimonate . Because nitrogen often limits net primary production due to its use in enzymes that mediate

510-482: The 5th century BC. Scotland, then a rather remote and un-industrialized region, retained manual methods into the 1700s. In Scottish Gaelic tradition, this process was accompanied by waulking songs , which women sang to set the pace. From the medieval period, the fulling of cloth was often done in a water mill , known as a fulling mill, a walk mill, or a tuck mill, and in Wales , a pandy. They appear to have originated in

540-708: The 9th or 10th century in Europe. The earliest known reference to a fulling mill in France, which dates from about 1086, was discovered in Normandy . There was a fulling mill established at Temple Guiting , Gloucestershire which was documented in the Domesday Book (also 1086). E. A. Lewis (possibly Welsh historian Edward Arthur Lewis ) observed: By the time of the Crusades in the late eleventh century, fulling mills were active throughout

570-425: The ammonium ion can be substituted with an alkyl group or some other organic group to form a substituted ammonium ion ( IUPAC nomenclature: aminium ion ). Depending on the number of organic groups, the ammonium cation is called a primary , secondary , tertiary , or quaternary . Except the quaternary ammonium cations, the organic ammonium cations are weak acids. An example of a reaction forming an ammonium ion

600-549: The ammonium ion is present in the salt, first, the salt is heated in presence of alkali hydroxide releasing a gas with a characteristic smell, which is ammonia . To further confirm ammonia, it is passed through a glass rod dipped in an HCl solution ( hydrochloric acid ), creating white dense fumes of ammonium chloride . Ammonia, when passed through CuSO 4 ( copper(II) sulfate ) solution, changes its color from blue to deep blue, forming Schweizer's reagent . Ammonia or ammonium ion when added to Nessler's reagent gives

630-440: The biochemical reactions that are necessary for life, ammonium is utilized by some microbes and plants. For example, energy is released by the oxidation of ammonium in a process known as nitrification , which produces nitrate and nitrite . This process is a form of autotrophy that is common amongst Nitrosomonas , Nitrobacter , Nitrosolobus , and Nitrosospira , amongst others. The amount of ammonium in soil that

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660-399: The biological communities that depend on it. The ammonium ion is generated when ammonia, a weak base, reacts with Brønsted acids ( proton donors): The ammonium ion is mildly acidic, reacting with Brønsted bases to return to the uncharged ammonia molecule: Thus, the treatment of concentrated solutions of ammonium salts with a strong base gives ammonia. When ammonia is dissolved in water,

690-413: The biological communities that rely on it. For example, increasing nitrogen content has been shown to increase plant growth, but aggravate soil phosphorus levels, which can impact microbial communities. The ammonium cation has very similar properties to the heavier alkali metal cations and is often considered a close equivalent. Ammonium is expected to behave as a metal ( [NH 4 ] ions in

720-404: The case of woollens , made from carded wool , but not for worsted materials made from combed wool. After this stage, water was used to rinse out the foul-smelling liquor used during cleansing. Felting of wool occurs upon hammering or other mechanical agitation because the microscopic scales on the surface of wool fibres hook together, somewhat like hook and loop fixings. Originally, fulling

750-424: The foot (the head of the hammer) struck the cloth almost horizontally. The stock had a tub holding the liquor and cloth. This was somewhat rounded on the side away from the hammer, so that the cloth gradually turned, ensuring that all parts of it were milled evenly. However, the cloth was taken out about every two hours to undo plaits and wrinkles. The 'foot' was approximately triangular in shape, with notches to assist

780-418: The medieval world. The mills beat the cloth with wooden hammers, known as fulling stocks or fulling hammers. Fulling stocks were of two kinds, falling stocks (operating vertically) that were used only for scouring, and driving or hanging stocks. In both cases the machinery was operated by cams on the shaft of a waterwheel or on a tappet wheel, which lifted the hammer. Driving stocks were pivoted so that

810-513: The oils encourages felting, and the cloth is pounded to clean it and to encourage the fibers to felt, so in practice the processes overlap. Urine was so important to the fulling business that it was taxed in Ancient Rome . Stale urine, known as wash or lant , was a source of ammonium salts and assisted in cleansing and whitening the cloth and having its fibers intertwined. By the medieval period, fuller's earth had been introduced for use in

840-399: The process. This is a soft clay-like material occurring naturally as an impure hydrous aluminium silicate . Worked through the cloth, it absorbs oils and dirt. It was used in conjunction with wash. More recently, soap has been used. The second function of fulling was to thicken cloth by matting the fibres together to give it strength and increase waterproofing ( felting ). This was vital in

870-563: The turning of the cloth. After fulling, cloth was stretched on great frames known as tenters, to which it is attached by tenterhooks (whence the phrase being on tenterhooks ). The area where the tenters were erected was known as a tenterground . Cloth would also have the nap raised by napping or gigging . The surface would then be sheared smooth. The process might be repeated for a smoother finish. The names for workers who performed these tasks ( fuller , tucker , and walker ) have become common surnames . The Welsh word for

900-485: Was carried out by the pounding of the woollen cloth with a club, or the fuller's feet or hands. In Roman times, fulling was conducted by slaves working the cloth while ankle deep in tubs of human urine . There are several Biblical references to fulling ( 2 Kings 18:17 ; Isaiah 7:3 and 36:2 ; Malachi 3:2 ; Mark 9:3 ). In addition to this, at least one reference appears in the speeches of Lysias , written in Athens during

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