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In May 2009 , the IUPAC / IUPAP Joint Working Party reported on the discovery of copernicium and acknowledged the discovery of the isotope 283Cn . This implied the de facto discovery of the livermorium @-@ 291 isotope , from the acknowledgment of the data relating to its granddaughter 283Cn , although the livermorium ... |
In recent years , the synthesis of livermorium has been separately confirmed in two other laboratories .
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= = = Naming = = =
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Using Mendeleev 's nomenclature for unnamed and undiscovered elements , livermorium is sometimes called eka @-@ polonium . In 1979 IUPAC recommended that the placeholder systematic element name ununhexium ( with the corresponding symbol of Uuh ) be used until the discovery of the element was confirmed and a name was d... |
According to IUPAC recommendations , the discoverer or discoverers of a new element have the right to suggest a name . The discovery of livermorium was recognized by the Joint Working Party ( JWP ) of IUPAC on 1 June 2011 , along with that of flerovium . According to the vice @-@ director of JINR , the Dubna team orig... |
= = Predicted properties = =
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= = = Nuclear stability and isotopes = = =
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Livermorium is expected to be near an island of stability centered on copernicium ( element 112 ) and flerovium ( element 114 ) . The reasons for the presence of this island are still not well understood . Due to the expected high fission barriers , any nucleus within this island of stability exclusively decays by alp... |
Superheavy elements are produced by nuclear fusion . These fusion reactions can be divided into " hot " and " cold " fusion , depending on the excitation energy of the compound nucleus produced . In hot fusion reactions , very light , high @-@ energy projectiles are accelerated toward very heavy targets ( actinides ) ... |
Important information could be gained regarding the properties of superheavy nuclei by the synthesis of more livermorium isotopes , specifically those with a few neutrons more or less than the known ones – 286Lv , 287Lv , 288Lv , 289Lv , 294Lv , and 295Lv . This is possible because there are many reasonably long @-@ l... |
The synthesis of 294Lv and 295Lv could be accomplished by fusing the heavy curium isotope curium @-@ 250 with calcium @-@ 48 . The cross section of this nuclear reaction would be about 1 picobarn . After a few alpha decays , these livermorium isotopes would reach nuclides at the line of beta stability . Additionally ,... |
Other possibilities to synthesize nuclei on the island of stability include quasifission ( partial fusion followed by fission ) of a massive nucleus . Such nuclei tend to fission , expelling doubly magic or nearly doubly magic fragments such as calcium @-@ 40 , tin @-@ 132 , lead @-@ 208 , or bismuth @-@ 209 . Recentl... |
= = = Physical and atomic = = =
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In the periodic table , livermorium is a member of group 16 , the chalcogens , in the periodic table , below oxygen , sulfur , selenium , tellurium , and polonium . Every previous chalcogen has six electrons in its valence shell , forming a valence electron configuration of ns2np4 . In livermorium 's case , the trend ... |
1 / 27p2
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3 / 2 .
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The inert pair effects in livermorium should be even stronger than for polonium and hence the + 2 oxidation state becomes more stable than the + 4 state , which would be stabilized only by the most electronegative ligands ; this is reflected in the expected ionization energies of livermorium , where there are large ga... |
= = = Chemical = = =
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Livermorium is projected to be the fourth member of the 7p series of chemical elements and the heaviest member of group 16 ( VIA ) in the Periodic Table , below polonium . While it is the least theoretically studied of the 7p elements , its chemistry is expected to be quite similar to that of polonium . The group oxid... |
Livermorane ( LvH2 ) would be the heaviest chalcogen hydride and the heaviest homolog of water ( the lighter ones being H2S , H2Se , H2Te , and PoH2 ) . Polane ( polonium hydride ) is a more covalent compound than most metal hydrides because polonium straddles the border between metals and metalloids and has some nonm... |
= = Experimental chemistry = =
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Unambiguous determination of the chemical characteristics of livermorium has not yet been established . In 2011 , experiments were conducted to create ununtrium , flerovium , and ununpentium isotopes in the reactions between calcium @-@ 48 projectiles and targets of americium @-@ 243 and plutonium @-@ 244 . The target... |
= American white ibis =
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The American white ibis ( Eudocimus albus ) is a species of bird in the ibis family , Threskiornithidae . It is found from North Carolina via the Gulf Coast of the United States south through most of the coastal New World tropics . This particular ibis is a medium @-@ sized bird with an overall white plumage , bright ... |
Their diet consists primarily of small aquatic prey , such as insects and small fishes . Crayfish are its preferred food in most regions , but it can adjust its diet according to the habitat and prey abundance . Its main foraging behavior is probing with its beak at the bottom of shallow water to feel for and capture ... |
During the breeding season , the American white ibis gathers in huge colonies near water . Pairs are predominantly monogamous and both parents care for the young , although males tend to engage in extra @-@ pair copulation with other females to increase their reproductive success . Males have also been found to pirate... |
Human pollution has affected the behavior of the American white ibis via an increase in the concentrations of methylmercury , which is released into the environment from untreated waste . Exposure to methylmercury alters the hormone levels of American white ibis , affecting their mating and nesting behavior and leadin... |
= = Taxonomy = =
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The American white ibis was one of the many bird species originally described by Carl Linnaeus in the 1758 10th edition of his Systema Naturae , where it was given the binomial name of Scolopax albus . The species name is the Latin adjective albus " white " . Alternative common names that have been used include Spanis... |
Johann Georg Wagler gave the species its current binomial name in 1832 when he erected the new genus Eudocimus , whose only other species is the scarlet ibis ( E. ruber ) . There has long been debate on whether the two should be considered subspecies or closely related species , and the American Ornithologists ' Union... |
However , in a field study published in 1987 , researchers Cristina Ramo and Benjamin Busto found evidence of interbreeding in a population where the ranges of the scarlet and white ibises overlap along the coast and in the Llanos region of Colombia and Venezuela . They observed individuals of the two species mating a... |
Ornithologists James Hancock and Jim Kushlan also consider the two to be a single species , with the differences in plumage , size , skin coloration and degree of bill darkening during breeding season forming the diagnostic characters . They have proposed the populations recontacted in northwestern South America after... |
= = Description = =
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The white plumage and pink facial skin of adult American white ibises are distinctive . Adults have black wingtips that are usually only visible in flight . In non @-@ breeding condition the long downcurved bill and long legs are bright red @-@ orange . During the first ten days of the breeding season , the skin darke... |
The newly hatched American white ibis is covered with purple down feathers , deepening to dark brown or black on the head and wings . The chest is often bare and there can be a white tuft on the head . The irises are brown . The exposed skin is pinkish initially , apart from the tip of the bill which is dark gray , bu... |
Like other species of ibis , the American white ibis flies with neck and legs outstretched , often in long loose lines or V formations — a 1986 field study in North Carolina noted over 80 % of adult ibis doing so , while juveniles rapidly took up the practice over the course of the summer . The resulting improvement i... |
The main call of the American white ibis is a honking sound , transcribed as urnk , urnk , or hunk , hunk . The call is used in flight , courtship or when disturbed . Birds also utter a muted huu @-@ huu @-@ huu call while foraging , and make a squealing call in courtship . Young in the nest give a high @-@ pitched zz... |
= = = Similar species = = =
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Immature American white and scarlet ibises are very difficult to tell apart , although scarlet ibises tend to have darker legs and bare skin around the face . An immature American white ibis could be mistaken for an immature glossy ibis , but the latter is wholly dark brown and lacks the white belly and rump . The adu... |
= = Distribution and habitat = =
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The American white ibis is most common in Florida , where over 30 @,@ 000 have been counted in a single breeding colony . It also occurs throughout the Caribbean , on both coasts of Mexico ( from Baja California southwards ) and Central America , and as far south as Columbia and Venezuela . The non @-@ breeding range ... |
The species is known to wander , and has been sighted , sometimes in small flocks , in states far out of its usual range .
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In North America , breeding takes place along the Atlantic coast , from the Carolinas south to Florida and thence west along the Gulf Coast . Laguna Cuyutlán is an isolated and regionally important wetland in the state of Colima on México 's west coast where a breeding colony has been recorded . American white ibises ... |
The American white ibis is found in a variety of habitats , although shallow coastal marshes , wetlands and mangrove swamps are preferred . It is also commonly found in muddy pools , on mudflats and even wet lawns . Populations that are away from the coast and shoreline , particularly in southern Florida , often resid... |
= = = Fossil record = = =
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Remains similar to the American white ibis have been found in Middle Pliocene deposits of the Bone Valley formation in central Florida , and Lower Pliocene deposits of the Yorktown Formation at Lee Creek in North Carolina . Two species , one living and one extinct , have been recovered from the Talara Tar Seeps in nor... |
= = Behavior = =
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A field study late in the Florida nesting season revealed that on an average day , adult American white ibis spent 10 @.@ 25 hours looking for food , 0 @.@ 75 hours flying , 13 hours resting , roosting , and attending to their nests . Much of the time roosting is spent preening , biting and working their feathers with... |
The American white ibis is territorial , defending the nesting and display sites against intruders . Agonistic or threat displays include lunging forward with the bill in a horizontal posture , and standing upright and snapping the bill opposite another bird engaging in the same display . Birds also lunge and bite , o... |
= = = Breeding and lifespan = = =
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The American white ibis pairs up in spring and breeds in huge colonies , often with other waterbird species . Nesting begins as soon as suitable foraging and nesting habitat is available . The female selects the site , usually in the branches of a tree or shrub , which is often over water , and builds the nest , and m... |
Although the American white ibis is predominantly monogamous and both sexes provide parental care to their young , the male often flies off to engage in extra pair copulation with other nesting females after mating with its primary female partner . These extra @-@ pair copulations are usually done after the within @-@... |
The breeding success of the American white ibis is sensitive to the hydrological conditions of the ecosystem such as rainfall and water levels . Low and decreasing water levels predict good prey accessibility . Water level reversals , where levels rise in the breeding season , disperse prey and impact on foraging succ... |
The main cause of nest failure among the species is due to nest abandonment , the leading cause of which is inundation from extremely high tides . Parents abandoned 61 % of all nesting starts either during or immediately after extremely high tides . The eggs float out of the flooded nests , or get washed out into the ... |
The eggs hatch after about three weeks and the young are attended by both parents . Males are present around the nest for most of the day , and females most of the night . The parents exchange nest duties in the morning and in the evening . Most of the feeding of the chicks occurs during the period where they swap nes... |
Bird predators may seize anywhere from 7 % to 75 % of the progeny in a breeding colony . The fish crow ( Corvus ossifragus ) is common raider of American white ibis nests , accounting for up to 44 % of egg loss in a field study at Battery Island , North Carolina . Other predators of eggs and young include the boat @-@... |
The American white ibis begins breeding in its third summer , although birds in captivity may breed as young as nine or ten months of age . The oldest member of the species recorded in captivity was over 20 years of age , and a wild bird has been picked up 16 years and 4 months after being banded .
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= = = Diet = = =
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The American white ibis prefers to eat crayfish and other crustaceans , but also takes aquatic insects and small fish . Outside the nesting season , the diet is highly variable , as abundance and types of prey depend on the both region and habitat . In Los Llanos , located on the border of Columbia and Venezuela , the... |
The American white ibis is found in mixed @-@ species foraging flocks with the glossy ibis ( Plegadis falcinellus ) in flooded fields , and the two species select different food items with little overlap ; the former foraging for crabs and aquatic insects and the latter feeding mainly on grain . The wood stork is also... |
= = = Foraging = = =
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During the summer , the American white ibis roams along the coast of tidal flats and mangrove swamps as the inland marshes are usually flooded . However , as the water level recedes in the fall , populations at the coast shift their foraging area inland , to inland marshes and swamplands . It has become more common in... |
The American white ibis is a tactile , nonvisual forager , which limits its ability to choose from a wide variety of prey . For the most part , the American white ibis forages for food by tactile probing . It wades slowly through shallow water and sticks its long , downcurved bill into the substrate of the water body ... |
Juveniles have lower foraging efficiency compared to adults and in most feeding flocks , the juveniles are usually outnumbered by the adults . They usually tend to stay close to one another and forage for food together at the peripheral region of the group . During the breeding season , adult male ibises have been rec... |
= = Parasites and mortality = =
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