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92-608: In 1984 important zinc and barium deposits were discovered in the Navarana Fjord. Australian Ironbark Zinc corporation was granted an exploration licence in 2007. This fjord was mapped by Danish Arctic explorer Eigil Knuth during the Danish Peary Land Expedition of 1947–1950. It was named after Navarana Mequpaluk (died 1921), the wife of Arctic explorer Peter Freuchen (1886–1957). Navarana had died at Upernavik in 1921 just before joining

184-409: A condenser . Some alchemists called this zinc oxide lana philosophica , Latin for "philosopher's wool", because it collected in wooly tufts, whereas others thought it looked like white snow and named it nix album . The name of the metal was probably first documented by Paracelsus , a Swiss-born German alchemist, who referred to the metal as "zincum" or "zinken" in his book Liber Mineralium II , in

276-428: A gamma ray . Zn has three excited metastable states and Zn has two. The isotopes Zn , Zn , Zn and Zn each have only one excited metastable state. The most common decay mode of a radioisotope of zinc with a mass number lower than 66 is electron capture . The decay product resulting from electron capture is an isotope of copper. The most common decay mode of

368-518: A by-product of smelting sulfide ores. Zinc in such remnants in smelting ovens was usually discarded as it was thought to be worthless. The manufacture of brass was known to the Romans by about 30 BC. They made brass by heating powdered calamine (zinc silicate or carbonate), charcoal and copper together in a crucible. The resulting calamine brass was then either cast or hammered into shape for use in weaponry. Some coins struck by Romans in

460-657: A defense mechanism". The following types of diarrhea may indicate further investigation is needed: A severity score is used to aid diagnosis in children. When diarrhea lasts for more than four weeks a number of further tests may be recommended including: A 2019 guideline recommended that testing for ova and parasites was only needed in people who are at high risk though they recommend routine testing for giardia . Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were not recommended. Worldwide in 2004, approximately 2.5 billion cases of diarrhea occurred, which resulted in 1.5 million deaths among children under

552-470: A few cases such as those who have bloody diarrhea and a high fever, those with severe diarrhea following travelling , and those who grow specific bacteria or parasites in their stool. Loperamide may help decrease the number of bowel movements but is not recommended in those with severe disease. About 1.7 to 5 billion cases of diarrhea occur per year. It is most common in developing countries , where young children get diarrhea on average three times

644-689: A frequent cause. In the elderly, particularly those who have been treated with antibiotics for unrelated infections, a toxin produced by Clostridioides difficile often causes severe diarrhea. Parasites, particularly protozoa e.g., Cryptosporidium spp., Giardia spp., Entamoeba histolytica , Blastocystis spp., Cyclospora cayetanensis , are frequently the cause of diarrhea that involves chronic infection. The broad-spectrum antiparasitic agent nitazoxanide has shown efficacy against many diarrhea-causing parasites. Other infectious agents, such as parasites or bacterial toxins, may exacerbate symptoms. In sanitary living conditions where there

736-400: A half-life of 243.66 days, is the least active radioisotope, followed by Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers , of which Zn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a metastable isotope is in an excited state and will return to the ground state by emitting a photon in the form of

828-413: A high glucose content are more absorbable and less likely to cause diarrhea. Sugar alcohols such as sorbitol (often found in sugar-free foods) are difficult for the body to absorb and, in large amounts, may lead to osmotic diarrhea. In most of these cases, osmotic diarrhea stops when the offending agent (e.g., milk or sorbitol) is stopped. Exudative diarrhea occurs with the presence of blood and pus in

920-435: A liquid, or "loose", bowel movement. Acute diarrhea is most commonly due to viral gastroenteritis with rotavirus , which accounts for 40% of cases in children under five. In travelers , however, bacterial infections predominate. Various toxins such as mushroom poisoning and drugs can also cause acute diarrhea. Chronic diarrhea can be the part of the presentations of a number of chronic medical conditions affecting

1012-515: A metal which, when oxidized, produces pushpanjan , thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period ( c.  322 and 187 BCE). The smelting of metallic zinc here, however, appears to have begun around the 12th century AD. One estimate is that this location produced an estimated million tonnes of metallic zinc and zinc oxide from

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1104-417: A metal–carbon sigma bond . Cobalticyanide paper (Rinnmann's test for Zn) can be used as a chemical indicator for zinc. 4 g of K 3 Co(CN) 6 and 1 g of KClO 3 is dissolved on 100 ml of water. Paper is dipped in the solution and dried at 100 °C. One drop of the sample is dropped onto the dry paper and heated. A green disc indicates the presence of zinc. Various isolated examples of

1196-464: A population, especially in the absence of water filtration or purification. Human feces contains a variety of potentially harmful human pathogens . Proper nutrition is important for health and functioning, including the prevention of infectious diarrhea. It is especially important to young children who do not have a fully developed immune system. Zinc deficiency , a condition often found in children in developing countries can, even in mild cases, have

1288-510: A process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques Daniel Dony built a different kind of horizontal zinc smelter in Belgium that processed even more zinc. Italian doctor Luigi Galvani discovered in 1780 that connecting

1380-596: A quantity of what he called "calay" (from the Malay or Hindi word for tin) originating from Malabar off a cargo ship captured from the Portuguese in the year 1596. Libavius described the properties of the sample, which may have been zinc. Zinc was regularly imported to Europe from the Orient in the 17th and early 18th centuries, but was at times very expensive. Metallic zinc was isolated in India by 1300 AD. Before it

1472-401: A radioisotope of zinc with mass number higher than 66 is beta decay (β ), which produces an isotope of gallium . Zinc has an electron configuration of [Ar]3d 4s and is a member of the group 12 of the periodic table . It is a moderately reactive metal and strong reducing agent . The surface of the pure metal tarnishes quickly, eventually forming a protective passivating layer of

1564-414: A result, if it is stopped, there might be a delay in recovery. They cite in support of this argument research published in 1973 that found that treating Shigella with the anti-diarrhea drug (Co-phenotrope, Lomotil ) caused people to stay feverish twice as long as those not so treated. The researchers indeed themselves observed that: "Lomotil may be contraindicated in shigellosis. Diarrhea may represent

1656-435: A series of tests of intelligence. Diarrhea can cause electrolyte imbalances , kidney impairment , dehydration , and defective immune system responses. When oral drugs are administered, the efficiency of the drug is to produce a therapeutic effect and the lack of this effect may be due to the medication travelling too quickly through the digestive system, limiting the time that it can be absorbed. Clinicians try to treat

1748-438: A significant impact on the development and proper functioning of the human immune system. Indeed, this relationship between zinc deficiency and reduced immune functioning corresponds with an increased severity of infectious diarrhea. Children who have lowered levels of zinc have a greater number of instances of diarrhea, severe diarrhea, and diarrhea associated with fever. Similarly, vitamin A deficiency can cause an increase in

1840-806: A week over the previous three months. Symptoms of diarrhea-predominant IBS can be managed through a combination of dietary changes, soluble fiber supplements and medications such as loperamide or codeine . About 30% of patients with diarrhea-predominant IBS have bile acid malabsorption diagnosed with an abnormal SeHCAT test. Diarrhea can be caused by other diseases and conditions, namely: Over 700 medications, such as penicillin , are known to cause diarrhea. The classes of medications that are known to cause diarrhea are laxatives, antacids, heartburn medications, antibiotics, anti-neoplastic drugs, anti-inflammatories as well as many dietary supplements. According to two researchers, Nesse and Williams , diarrhea may function as an evolved expulsion defense mechanism. As

1932-484: A year. Total deaths from diarrhea are estimated at 1.53 million in 2019—down from 2.9 million in 1990. In 2012, it was the second most common cause of deaths in children younger than five (0.76 million or 11%). Frequent episodes of diarrhea are also a common cause of malnutrition and the most common cause in those younger than five years of age. Other long term problems that can result include stunted growth and poor intellectual development. The word diarrhea

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2024-495: A zinc atom in the reactive center are widespread in biochemistry, such as alcohol dehydrogenase in humans. Consumption of excess zinc may cause ataxia , lethargy , and copper deficiency . In marine biomes, notably within polar regions, a deficit of zinc can compromise the vitality of primary algal communities, potentially destabilizing the intricate marine trophic structures and consequently impacting biodiversity. Brass , an alloy of copper and zinc in various proportions,

2116-430: Is isotonic with plasma even during fasting. It continues even when there is no oral food intake. Osmotic diarrhea occurs when too much water is drawn into the bowels. If a person drinks solutions with excessive sugar or excessive salt, these can draw water from the body into the bowel and cause osmotic diarrhea. Osmotic diarrhea can also result from maldigestion (e.g., pancreatic disease or coeliac disease ) in which

2208-403: Is a chalcophile , meaning the element is more likely to be found in minerals together with sulfur and other heavy chalcogens , rather than with the light chalcogen oxygen or with non-chalcogen electronegative elements such as the halogens . Sulfides formed as the crust solidified under the reducing conditions of the early Earth's atmosphere. Sphalerite , which is a form of zinc sulfide,

2300-475: Is a chemical element with the symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table . In some respects, zinc is chemically similar to magnesium : both elements exhibit only one normal oxidation state (+2), and the Zn and Mg ions are of similar size. Zinc

2392-646: Is a symptom of, among others, Shigella , Entamoeba histolytica , and Salmonella . Diarrheal disease may have a negative impact on both physical fitness and mental development. "Early childhood malnutrition resulting from any cause reduces physical fitness and work productivity in adults", and diarrhea is a primary cause of childhood malnutrition. Further, evidence suggests that diarrheal disease has significant impacts on mental development and health; it has been shown that, even when controlling for helminth infection and early breastfeeding, children who had experienced severe diarrhea had significantly lower scores on

2484-479: Is ample food and a supply of clean water, an otherwise healthy person usually recovers from viral infections in a few days. However, for ill or malnourished individuals, diarrhea can lead to severe dehydration and can become life-threatening. Open defecation is a leading cause of infectious diarrhea leading to death. Poverty is a good indicator of the rate of infectious diarrhea in a population. This association does not stem from poverty itself, but rather from

2576-442: Is an increase in the active secretion, or there is an inhibition of absorption. There is little to no structural damage. The most common cause of this type of diarrhea is a cholera toxin that stimulates the secretion of anions , especially chloride ions (Cl ). Therefore, to maintain a charge balance in the gastrointestinal tract , sodium (Na ) is carried with it, along with water. In this type of diarrhea intestinal fluid secretion

2668-535: Is an infection of the intestines due to a virus , bacterium , or parasite —a condition also known as gastroenteritis . These infections are often acquired from food or water that has been contaminated by feces , or directly from another person who is infected. The three types of diarrhea are: short duration watery diarrhea, short duration bloody diarrhea, and persistent diarrhea (lasting more than two weeks, which can be either watery or bloody). The short duration watery diarrhea may be due to cholera , although this

2760-546: Is being smelted. In Britain, John Lane is said to have carried out experiments to smelt zinc, probably at Landore , prior to his bankruptcy in 1726. In 1738 in Great Britain, William Champion patented a process to extract zinc from calamine in a vertical retort -style smelter. His technique resembled that used at Zawar zinc mines in Rajasthan , but no evidence suggests he visited the Orient. Champion's process

2852-584: Is best known in humans, it affects many other species, notably among primates . The cecal appendix , when present, appears to afford some protection against diarrhea to young primates. Numerous studies have shown that improvements in drinking water and sanitation ( WASH ) lead to decreased risks of diarrhoea. Such improvements might include for example use of water filters, provision of high-quality piped water and sewer connections. In institutions, communities, and households, interventions that promote hand washing with soap lead to significant reductions in

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2944-539: Is defined by the World Health Organization as having three or more loose or liquid stools per day, or as having more stools than is normal for that person. Acute diarrhea is defined as an abnormally frequent discharge of semisolid or fluid fecal matter from the bowel, lasting less than 14 days, by World Gastroenterology Organization . Acute diarrhea that is watery may be known as AWD (Acute Watery Diarrhoea.) Secretory diarrhea means that there

3036-674: Is from the Ancient Greek διάρροια from διά dia "through" and ῥέω rheo "flow". Diarrhea is the spelling in American English , whereas diarrhoea is the spelling in British English . Slang terms for the condition include "the runs", "the squirts" (or "squits" in Britain ) and "the trots". The word is often pronounced as / ˌ d aɪ ə ˈ r iː ə / DY -ə- REE -ə . Diarrhea

3128-527: Is hard and brittle at most temperatures but becomes malleable between 100 and 150 °C. Above 210 °C, the metal becomes brittle again and can be pulverized by beating. Zinc is a fair conductor of electricity . For a metal, zinc has relatively low melting (419.5 °C) and boiling point (907 °C). The melting point is the lowest of all the d-block metals aside from mercury and cadmium ; for this reason among others, zinc, cadmium, and mercury are often not considered to be transition metals like

3220-464: Is implicated by the formation of a yellow diamagnetic glass by dissolving metallic zinc in molten ZnCl 2 . The [Zn 2 ] core would be analogous to the [Hg 2 ] cation present in mercury (I) compounds. The diamagnetic nature of the ion confirms its dimeric structure. The first zinc(I) compound containing the Zn–Zn bond, (η -C 5 Me 5 ) 2 Zn 2 . Binary compounds of zinc are known for most of

3312-410: Is known as Special High Grade, often abbreviated SHG , and is 99.995% pure. Worldwide, 95% of new zinc is mined from sulfidic ore deposits, in which sphalerite (ZnS) is nearly always mixed with the sulfides of copper, lead and iron. Zinc mines are scattered throughout the world, with the main areas being China, Australia, and Peru. China produced 38% of the global zinc output in 2014. Zinc metal

3404-545: Is necessary for prenatal and postnatal development. It is the second most abundant trace metal in humans after iron and it is the only metal which appears in all enzyme classes . Zinc is also an essential nutrient element for coral growth as it is an important cofactor for many enzymes. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children, deficiency causes growth retardation, delayed sexual maturation, infection susceptibility, and diarrhea . Enzymes with

3496-524: Is necessary for the leaching process. If deposits of zinc carbonate , zinc silicate , or zinc-spinel (like the Skorpion Deposit in Namibia ) are used for zinc production, the roasting can be omitted. For further processing two basic methods are used: pyrometallurgy or electrowinning . Pyrometallurgy reduces zinc oxide with carbon or carbon monoxide at 950 °C (1,740 °F) into

3588-437: Is produced using extractive metallurgy . The ore is finely ground, then put through froth flotation to separate minerals from gangue (on the property of hydrophobicity ), to get a zinc sulfide ore concentrate consisting of about 50% zinc, 32% sulfur, 13% iron, and 5% SiO 2 . Roasting converts the zinc sulfide concentrate to zinc oxide: The sulfur dioxide is used for the production of sulfuric acid, which

3680-437: Is rare in the developed world. If blood is present, it is also known as dysentery . A number of non-infectious causes can result in diarrhea. These include lactose intolerance , irritable bowel syndrome , non-celiac gluten sensitivity , celiac disease , inflammatory bowel disease such as ulcerative colitis , hyperthyroidism , bile acid diarrhea , and a number of medications. In most cases, stool cultures to confirm

3772-642: Is the 24th most abundant element in Earth's crust and has five stable isotopes . The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting , and final extraction using electricity ( electrowinning ). Zinc is an essential trace element for humans, animals, plants and for microorganisms and

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3864-554: Is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin with loss of the normal stretchiness of the skin and irritable behaviour. This can progress to decreased urination , loss of skin color , a fast heart rate , and a decrease in responsiveness as it becomes more severe. Loose but non-watery stools in babies who are exclusively breastfed , however, are normal. The most common cause

3956-473: Is the most common cause in children under five years old. Adenovirus types 40 and 41, and astroviruses cause a significant number of infections. Shiga-toxin producing Escherichia coli , such as E coli o157:h7 , are the most common cause of infectious bloody diarrhea in the United States. Campylobacter spp. are a common cause of bacterial diarrhea, but infections by Salmonella spp., Shigella spp. and some strains of Escherichia coli are also

4048-532: Is the most heavily mined zinc-containing ore because its concentrate contains 60–62% zinc. Other source minerals for zinc include smithsonite (zinc carbonate ), hemimorphite (zinc silicate ), wurtzite (another zinc sulfide), and sometimes hydrozincite (basic zinc carbonate ). With the exception of wurtzite, all these other minerals were formed by weathering of the primordial zinc sulfides. Identified world zinc resources total about 1.9–2.8 billion tonnes . Large deposits are in Australia, Canada and

4140-515: The Paleozoic Franklinian Basin . Navarana Fjord is part of an escarpment at the northern edge of a Silurian limestone shelf with a fault running for 500 km (310 mi) reaching Nyeboe Land . Sisamatispongia is a genus of fossil sponges whose spicules are only recorded from Navarana Fjord. This Greenland location article is a stub . You can help Misplaced Pages by expanding it . Zinc Zinc

4232-469: The metalloids and all the nonmetals except the noble gases . The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric , dissolving in both strong basic and acidic solutions. The other chalcogenides ( ZnS , ZnSe , and ZnTe ) have varied applications in electronics and optics. Pnictogenides ( Zn 3 N 2 , Zn 3 P 2 , Zn 3 As 2 and Zn 3 Sb 2 ),

4324-518: The spinal cord of a freshly dissected frog to an iron rail attached by a brass hook caused the frog's leg to twitch. He incorrectly thought he had discovered an ability of nerves and muscles to create electricity and called the effect " animal electricity ". The galvanic cell and the process of galvanization were both named for Luigi Galvani, and his discoveries paved the way for electrical batteries , galvanization, and cathodic protection . Galvani's friend, Alessandro Volta , continued researching

4416-403: The 12th to 16th centuries. Another estimate gives a total production of 60,000 tonnes of metallic zinc over this period. The Rasaratna Samuccaya , written in approximately the 13th century AD, mentions two types of zinc-containing ores: one used for metal extraction and another used for medicinal purposes. Zinc was distinctly recognized as a metal under the designation of Yasada or Jasada in

4508-619: The 16th century. The word is probably derived from the German zinke , and supposedly meant "tooth-like, pointed or jagged" (metallic zinc crystals have a needle-like appearance). Zink could also imply "tin-like" because of its relation to German zinn meaning tin. Yet another possibility is that the word is derived from the Persian word سنگ seng meaning stone. The metal was also called Indian tin , tutanego , calamine , and spinter . German metallurgist Andreas Libavius received

4600-422: The 24th most abundant element. It also makes up 312 ppm of the solar system, where it is the 22nd most abundant element. Typical background concentrations of zinc do not exceed 1 μg/m in the atmosphere; 300 mg/kg in soil; 100 mg/kg in vegetation; 20 μg/L in freshwater and 5 μg/L in seawater. The element is normally found in association with other base metals such as copper and lead in ores . Zinc

4692-570: The Christian era are made of what is probably calamine brass. The oldest known pills were made of the zinc carbonates hydrozincite and smithsonite. The pills were used for sore eyes and were found aboard the Roman ship Relitto del Pozzino , wrecked in 140 BC. The Berne zinc tablet is a votive plaque dating to Roman Gaul made of an alloy that is mostly zinc. The Charaka Samhita , thought to have been written between 300 and 500 AD, mentions

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4784-573: The Fifth Thule Expedition with her husband. Her death came at the time of the influenza epidemic that ravaged indigenous populations in Greenland in the early 1920s. Navarana Fjord is located in the northeastern part of Freuchen Land , western Peary Land. It is the only significant branch of J.P. Koch Fjord , with the junction about 45 km (28 mi) east of the mouth in the southern shore. The fjord runs roughly southwards in

4876-478: The United States, with the largest reserves in Iran . The most recent estimate of reserve base for zinc (meets specified minimum physical criteria related to current mining and production practices) was made in 2009 and calculated to be roughly 480 Mt. Zinc reserves, on the other hand, are geologically identified ore bodies whose suitability for recovery is economically based (location, grade, quality, and quantity) at

4968-610: The age of five. Greater than half of these were in Africa and South Asia. This is down from a death rate of 4.5 million in 1980 for gastroenteritis. Diarrhea remains the second leading cause of infant mortality (16%) after pneumonia (17%) in this age group. The majority of such cases occur in the developing world, with over half of the recorded cases of childhood diarrhea occurring in Africa and Asia , with 696 million and 1.2 billion cases, respectively, compared to only 480 million in

5060-419: The basic zinc carbonate , Zn 5 (OH) 6 (CO 3 ) 2 , by reaction with atmospheric carbon dioxide . Zinc burns in air with a bright bluish-green flame, giving off fumes of zinc oxide . Zinc reacts readily with acids , alkalis and other non-metals. Extremely pure zinc reacts only slowly at room temperature with acids. Strong acids, such as hydrochloric or sulfuric acid , can remove

5152-419: The bloodstream via the intestinal tract in the small intestine. Prior to defecation, the large intestine reabsorbs the water and other digestive solvents in the waste product in order to maintain proper hydration and overall equilibrium. Diarrhea occurs when the large intestine is prevented, for any number of reasons, from sufficiently absorbing the water or other digestive fluids from fecal matter, resulting in

5244-420: The chromate ZnCrO 4 (one of the few colored zinc compounds) are a few examples of other common inorganic compounds of zinc. Organozinc compounds are those that contain zinc– carbon covalent bonds. Diethylzinc ( (C 2 H 5 ) 2 Zn ) is a reagent in synthetic chemistry. It was first reported in 1848 from the reaction of zinc and ethyl iodide , and was the first compound known to contain

5336-455: The conditions under which impoverished people live. The absence of certain resources compromises the ability of the poor to defend themselves against infectious diarrhea. "Poverty is associated with poor housing, crowding, dirt floors, lack of access to clean water or to sanitary disposal of fecal waste ( sanitation ), cohabitation with domestic animals that may carry human pathogens, and a lack of refrigerated storage for food, all of which increase

5428-637: The diarrheas by reducing the dosage of medication, changing the dosing schedule, discontinuation of the drug, and rehydration. The interventions to control the diarrhea are not often effective. Diarrhea can have a profound effect on the quality of life because fecal incontinence is one of the leading factors for placing older adults in long term care facilities (nursing homes). In the latter stages of human digestion, ingested materials are inundated with water and digestive fluids such as gastric acid , bile , and digestive enzymes in order to break them down into their nutrient components, which are then absorbed into

5520-569: The effect and invented the Voltaic pile in 1800. Volta's pile consisted of a stack of simplified galvanic cells , each being one plate of copper and one of zinc connected by an electrolyte . By stacking these units in series, the Voltaic pile (or "battery") as a whole had a higher voltage, which could be used more easily than single cells. Electricity is produced because the Volta potential between

5612-469: The exact cause are not required. Diarrhea can be prevented by improved sanitation , clean drinking water , and hand washing with soap. Breastfeeding for at least six months and vaccination against rotavirus is also recommended. Oral rehydration solution (ORS)—clean water with modest amounts of salts and sugar —is the treatment of choice. Zinc tablets are also recommended. These treatments have been estimated to have saved 50 million children in

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5704-439: The formation of Zn 2 Cl 2 , a zinc compound with a +1 oxidation state. No compounds of zinc in positive oxidation states other than +1 or +2 are known. Calculations indicate that a zinc compound with the oxidation state of +4 is unlikely to exist. Zn(III) is predicted to exist in the presence of strongly electronegative trianions; however, there exists some doubt around this possibility. But in 2021 another compound

5796-504: The frequency of diarrhea   ... Poverty also restricts the ability to provide age-appropriate, nutritionally balanced diets or to modify diets when diarrhea develops so as to mitigate and repair nutrient losses. The impact is exacerbated by the lack of adequate, available, and affordable medical care." One of the most common causes of infectious diarrhea is a lack of clean water. Often, improper fecal disposal leads to contamination of groundwater. This can lead to widespread infection among

5888-461: The hydroxide Zn(OH) 2 forms as a white precipitate . In stronger alkaline solutions, this hydroxide is dissolved to form zincates ( [Zn(OH) 4 ] ). The nitrate Zn(NO 3 ) 2 , chlorate Zn(ClO 3 ) 2 , sulfate ZnSO 4 , phosphate Zn 3 (PO 4 ) 2 , molybdate ZnMoO 4 , cyanide Zn(CN) 2 , arsenite Zn(AsO 2 ) 2 , arsenate Zn(AsO 4 ) 2 ·8H 2 O and

5980-429: The intestine. Common causes include ulcerative colitis , Crohn's disease , microscopic colitis , celiac disease , irritable bowel syndrome , and bile acid malabsorption . There are many causes of infectious diarrhea, which include viruses , bacteria and parasites. Infectious diarrhea is frequently referred to as gastroenteritis . Norovirus is the most common cause of viral diarrhea in adults, but rotavirus

6072-459: The medical Lexicon ascribed to the Hindu king Madanapala (of Taka dynasty) and written about the year 1374. Smelting and extraction of impure zinc by reducing calamine with wool and other organic substances was accomplished in the 13th century in India. The Chinese did not learn of the technique until the 17th century. Alchemists burned zinc metal in air and collected the resulting zinc oxide on

6164-450: The metal, which is distilled as zinc vapor to separate it from other metals, which are not volatile at those temperatures. The zinc vapor is collected in a condenser. The equations below describe this process: In electrowinning , zinc is leached from the ore concentrate by sulfuric acid and impurities are precipitated: Diarrhea Diarrhea ( American English ), also spelled diarrhoea or diarrhœa ( British English ),

6256-557: The middle fjord zone, deeply dividing the Freuchen Land Peninsula. It is about 40 km (25 mi) in length and high mountains rise on both sides of the shore, with impressive up to 1,300 m (4,300 ft) high cliffs in some places. There is a fairly large glacier , the Navarana Fjord Glacier, at the head of the fjord discharging from the southeast. Geologically this fjord is located in

6348-575: The nutrients are left in the lumen to pull in water. Or it can be caused by osmotic laxatives (which work to alleviate constipation by drawing water into the bowels). In healthy individuals, too much magnesium , vitamin C or undigested lactose can produce osmotic diarrhea and distention of the bowel. A person who has lactose intolerance can have difficulty absorbing lactose after an extraordinarily high intake of dairy products. In persons who have fructose malabsorption , excess fructose intake can also cause diarrhea. High-fructose foods that also have

6440-420: The organic laboratory. Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure , with a distorted form of hexagonal close packing , in which each atom has six nearest neighbors (at 265.9 pm) in its own plane and six others at a greater distance of 290.6 pm. The metal

6532-417: The other types of diarrhea can be found in this type of diarrhea. It can be caused by bacterial infections, viral infections, parasitic infections, or autoimmune problems such as inflammatory bowel diseases. It can also be caused by tuberculosis, colon cancer, and enteritis. If there is blood visible in the stools, it is also known as dysentery . The blood is a trace of an invasion of bowel tissue. Dysentery

6624-525: The passivating layer and the subsequent reaction with the acid releases hydrogen gas. The chemistry of zinc is dominated by the +2 oxidation state. When compounds in this oxidation state are formed, the outer shell s electrons are lost, yielding a bare zinc ion with the electronic configuration [Ar]3d . In aqueous solution an octahedral complex, [Zn(H 2 O) 6 ] is the predominant species. The volatilization of zinc in combination with zinc chloride at temperatures above 285 °C indicates

6716-403: The past 25 years. When people have diarrhea it is recommended that they continue to eat healthy food, and babies continue to be breastfed. If commercial ORS is not available, homemade solutions may be used. In those with severe dehydration, intravenous fluids may be required. Most cases, however, can be managed well with fluids by mouth. Antibiotics , while rarely used, may be recommended in

6808-406: The peroxide ( ZnO 2 ), the hydride ( ZnH 2 ), and the carbide ( ZnC 2 ) are also known. Of the four halides , ZnF 2 has the most ionic character, while the others ( ZnCl 2 , ZnBr 2 , and ZnI 2 ) have relatively low melting points and are considered to have more covalent character. In weak basic solutions containing Zn ions,

6900-512: The potential for increased risk of disease contraction. Malabsorption is the inability to absorb food fully, mostly from disorders in the small bowel, but also due to maldigestion from diseases of the pancreas . Causes include: The two overlapping types here are of unknown origin: Another possible cause of diarrhea is irritable bowel syndrome (IBS), which usually presents with abdominal discomfort relieved by defecation and unusual stool (diarrhea or constipation ) for at least three days

6992-399: The remainder, have been found that are 2,500 years old. A possibly prehistoric statuette containing 87.5% zinc was found in a Dacian archaeological site. Strabo writing in the 1st century BC (but quoting a now lost work of the 4th century BC historian Theopompus ) mentions "drops of false silver" which when mixed with copper make brass. This may refer to small quantities of zinc that is

7084-541: The reserve lifetime for zinc has remained unchanged. About 346 million tonnes have been extracted throughout history to 2002, and scholars have estimated that about 109–305 million tonnes are in use. Five stable isotopes of zinc occur in nature, with Zn being the most abundant isotope (49.17% natural abundance ). The other isotopes found in nature are Zn (27.73%), Zn (4.04%), Zn (18.45%), and Zn (0.61%). Several dozen radioisotopes have been characterized. Zn , which has

7176-497: The rest of the d-block metals. Many alloys contain zinc, including brass. Other metals long known to form binary alloys with zinc are aluminium , antimony , bismuth , gold , iron, lead , mercury, silver , tin , magnesium , cobalt , nickel , tellurium , and sodium . Although neither zinc nor zirconium is ferromagnetic , their alloy, ZrZn 2 , exhibits ferromagnetism below 35  K . Zinc makes up about 75  ppm  (0.0075%) of Earth's crust , making it

7268-751: The rest of the world. Infectious diarrhea resulted in about 0.7 million deaths in children under five years old in 2011 and 250 million lost school days. In the Americas, diarrheal disease accounts for a total of 10% of deaths among children aged 1–59 months while in South East Asia, it accounts for 31.3% of deaths. It is estimated that around 21% of child mortalities in developing countries are due to diarrheal disease. The World Health Organization has reported that "deaths due to diarrhoeal diseases have dropped by 45%, from sixth leading cause of death in 2000 to thirteenth in 2021." Even though diarrhea

7360-529: The same crystal structure , and in other circumstances where ionic radius is a determining factor, the chemistry of zinc has much in common with that of magnesium. In other respects, there is little similarity with the late first-row transition metals. Zinc tends to form bonds with a greater degree of covalency and much more stable complexes with N - and S - donors. Complexes of zinc are mostly 4- or 6- coordinate , although 5-coordinate complexes are known. Zinc(I) compounds are very rare. The [Zn 2 ] ion

7452-598: The second known zinc-containing enzyme in 1955. Zinc is the fourth most common metal in use, trailing only iron , aluminium , and copper with an annual production of about 13 million tonnes. The world's largest zinc producer is Nyrstar , a merger of the Australian OZ Minerals and the Belgian Umicore . About 70% of the world's zinc originates from mining, while the remaining 30% comes from recycling secondary zinc. Commercially pure zinc

7544-432: The severity of diarrheal episodes. However, there is some discrepancy when it comes to the impact of vitamin A deficiency on the rate of disease. While some argue that a relationship does not exist between the rate of disease and vitamin A status, others suggest an increase in the rate associated with deficiency. Given that estimates suggest 127 million preschool children worldwide are vitamin A deficient, this population has

7636-415: The stool. This occurs with inflammatory bowel diseases , such as Crohn's disease or ulcerative colitis , and other severe infections such as E. coli or other forms of food poisoning. Inflammatory diarrhea occurs when there is damage to the mucosal lining or brush border, which leads to a passive loss of protein-rich fluids and a decreased ability to absorb these lost fluids. Features of all three of

7728-533: The time of determination. Since exploration and mine development is an ongoing process, the amount of zinc reserves is not a fixed number and sustainability of zinc ore supplies cannot be judged by simply extrapolating the combined mine life of today's zinc mines. This concept is well supported by data from the United States Geological Survey (USGS), which illustrates that although refined zinc production increased 80% between 1990 and 2010,

7820-423: The two metal plates makes electrons flow from the zinc to the copper and corrode the zinc. The non-magnetic character of zinc and its lack of color in solution delayed discovery of its importance to biochemistry and nutrition. This changed in 1940 when carbonic anhydrase , an enzyme that scrubs carbon dioxide from blood, was shown to have zinc in its active site . The digestive enzyme carboxypeptidase became

7912-498: The use of impure zinc in ancient times have been discovered. Zinc ores were used to make the zinc–copper alloy brass thousands of years prior to the discovery of zinc as a separate element. Judean brass from the 14th to 10th centuries BC contains 23% zinc. Knowledge of how to produce brass spread to Ancient Greece by the 7th century BC, but few varieties were made. Ornaments made of alloys containing 80–90% zinc, with lead, iron, antimony , and other metals making up

8004-593: Was isolated in Europe, it was imported from India in about 1600 CE. Postlewayt 's Universal Dictionary , a contemporary source giving technological information in Europe, did not mention zinc before 1751 but the element was studied before then. Flemish metallurgist and alchemist P. M. de Respour reported that he had extracted metallic zinc from zinc oxide in 1668. By the start of the 18th century, Étienne François Geoffroy described how zinc oxide condenses as yellow crystals on bars of iron placed above zinc ore that

8096-477: Was known to the ancient Romans and Greeks. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. The oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called " philosopher's wool " or "white snow". The element

8188-786: Was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion -resistant zinc plating of iron ( hot-dip galvanizing ) is the major application for zinc. Other applications are in electrical batteries , small non-structural castings, and alloys such as brass. A variety of zinc compounds are commonly used, such as zinc carbonate and zinc gluconate (as dietary supplements), zinc chloride (in deodorants), zinc pyrithione (anti- dandruff shampoos), zinc sulfide (in luminescent paints), and dimethylzinc or diethylzinc in

8280-421: Was reported with more evidence that had the oxidation state of +3 with the formula ZnBeB 11 (CN) 12 . Zinc chemistry is similar to the chemistry of the late first-row transition metals, nickel and copper, though it has a filled d-shell and compounds are diamagnetic and mostly colorless. The ionic radii of zinc and magnesium happen to be nearly identical. Because of this some of the equivalent salts have

8372-539: Was used as early as the third millennium BC in the Aegean area and the region which currently includes Iraq , the United Arab Emirates , Kalmykia , Turkmenistan and Georgia . In the second millennium BC it was used in the regions currently including West India , Uzbekistan , Iran , Syria , Iraq, and Israel . Zinc metal was not produced on a large scale until the 12th century in India, though it

8464-507: Was used through 1851. German chemist Andreas Marggraf normally gets credit for isolating pure metallic zinc in the West, even though Swedish chemist Anton von Swab had distilled zinc from calamine four years previously. In his 1746 experiment, Marggraf heated a mixture of calamine and charcoal in a closed vessel without copper to obtain a metal. This procedure became commercially practical by 1752. William Champion's brother, John, patented

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