1.
National Register of Historic Places
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The National Register of Historic Places is the United States federal governments official list of districts, sites, buildings, structures, and objects deemed worthy of preservation. The passage of the National Historic Preservation Act in 1966 established the National Register, of the more than one million properties on the National Register,80,000 are listed individually. The remainder are contributing resources within historic districts, each year approximately 30,000 properties are added to the National Register as part of districts or by individual listings. For most of its history the National Register has been administered by the National Park Service and its goals are to help property owners and interest groups, such as the National Trust for Historic Preservation, coordinate, identify, and protect historic sites in the United States. While National Register listings are mostly symbolic, their recognition of significance provides some financial incentive to owners of listed properties, protection of the property is not guaranteed. During the nomination process, the property is evaluated in terms of the four criteria for inclusion on the National Register of Historic Places, the application of those criteria has been the subject of criticism by academics of history and preservation, as well as the public and politicians. Occasionally, historic sites outside the proper, but associated with the United States are also listed. Properties can be nominated in a variety of forms, including individual properties, historic districts, the Register categorizes general listings into one of five types of properties, district, site, structure, building, or object. National Register Historic Districts are defined geographical areas consisting of contributing and non-contributing properties, some properties are added automatically to the National Register when they become administered by the National Park Service. These include National Historic Landmarks, National Historic Sites, National Historical Parks, National Military Parks/Battlefields, National Memorials, on October 15,1966, the Historic Preservation Act created the National Register of Historic Places and the corresponding State Historic Preservation Offices. Initially, the National Register consisted of the National Historic Landmarks designated before the Registers creation, approval of the act, which was amended in 1980 and 1992, represented the first time the United States had a broad-based historic preservation policy. To administer the newly created National Register of Historic Places, the National Park Service of the U. S. Department of the Interior, hartzog, Jr. established an administrative division named the Office of Archeology and Historic Preservation. Hartzog charged OAHP with creating the National Register program mandated by the 1966 law, ernest Connally was the Offices first director. Within OAHP new divisions were created to deal with the National Register, the first official Keeper of the Register was William J. Murtagh, an architectural historian. During the Registers earliest years in the late 1960s and early 1970s, organization was lax and SHPOs were small, understaffed, and underfunded. A few years later in 1979, the NPS history programs affiliated with both the U. S. National Parks system and the National Register were categorized formally into two Assistant Directorates. Established were the Assistant Directorate for Archeology and Historic Preservation and the Assistant Directorate for Park Historic Preservation, from 1978 until 1981, the main agency for the National Register was the Heritage Conservation and Recreation Service of the United States Department of the Interior. In February 1983, the two assistant directorates were merged to promote efficiency and recognize the interdependency of their programs, jerry L. Rogers was selected to direct this newly merged associate directorate
2.
Historic districts in the United States
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Buildings, structures, objects and sites within a historic district are normally divided into two categories, contributing and non-contributing. Districts greatly vary in size, some have hundreds of structures, the U. S. federal government designates historic districts through the United States Department of Interior under the auspices of the National Park Service. Federally designated historic districts are listed on the National Register of Historic Places, state-level historic districts may follow similar criteria or may require adherence to certain historic rehabilitation standards. Local historic district designation offers, by far, the most legal protection for historic properties because most land use decisions are made at the local level, local districts are generally administered by the county or municipal government. The first U. S. historic district was established in Charleston, South Carolina in 1931, Charleston city government designated an Old and Historic District by local ordinance and created a board of architectural review to oversee it. New Orleans followed in 1937, establishing the Vieux Carré Commission, other localities picked up on the concept, with the city of Philadelphia enacting its historic preservation ordinance in 1955. The Supreme Court case validated the protection of resources as an entirely permissible governmental goal. In 1966 the federal government created the National Register of Historic Places, conference of Mayors had stated Americans suffered from rootlessness. By the 1980s there were thousands of federally designated historic districts, Historic districts are generally two types of properties, contributing and non-contributing. In general, contributing properties are integral parts of the historic context, in addition to the two types of classification within historic districts, properties listed on the National Register of Historic Places are classified into five broad categories. They are, building, structure, site, district and object, all but the eponymous district category are also applied to historic districts listed on the National Register. A listing on the National Register of Historic Places is governmental acknowledgment of a historic district, however, the Register is an honorary status with some federal financial incentives. The National Register of Historic Places defines a historic district per U. S. federal law, a district may also comprise individual elements separated geographically but linked by association or history. Districts established under U. S. federal guidelines generally begin the process of designation through a nomination to the National Register of Historic Places, the National Register is the official recognition by the U. S. government of cultural resources worthy of preservation. While designation through the National Register does offer a district or property some protections, if the federal government is not involved, then the listing on the National Register provides the site, property or district no protections. If, however, company A was under federal contract the Smith House would be protected, a federal designation is little more than recognition by the government that the resource is worthy of preservation. Usually, the National Register does not list religious structures, moved structures, reconstructed structures, however, if a property falls into one of those categories and are integral parts of districts that do meet the criteria then an exception allowing their listing will be made. Historic district listings, like all National Register nominations, can be rejected on the basis of owner disapproval, in the case of historic districts, a majority of owners must object in order to nullify a nomination to the National Register of Historic Places
3.
Unincorporated area
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Occasionally, municipalities dissolve or disincorporate, which may happen if they become fiscally insolvent, and services become the responsibility of a higher administration. In some countries, such as in Brazil, Japan, France or the United Kingdom, unlike many other countries, Australia has only one level of local government immediately beneath state and territorial governments. A local government area often contains several towns and even entire cities, thus, aside from very sparsely populated areas and a few other special cases, almost all of Australia is part of an LGA. Unincorporated areas are often in locations, cover vast areas or have very small populations. Postal addresses in unincorporated areas, as in parts of Australia. Thus, there is any ambiguity regarding addresses in unincorporated areas. The Australian Capital Territory has no municipalities and is in some sense an unincorporated area, the territorial government is directly responsible for matters normally carried out by local government. The far west and north of New South Wales constitutes the Unincorporated Far West Region, a civil servant in the state capital manages such matters as are necessary. The second unincorporated area of state is Lord Howe Island. In the Northern Territory,1. 45% of the area and 4. In South Australia, 60% of the area is unincorporated and communities located within can receive services provided by a state agency. Firstly, the remote area that is unincorporated is the Abrolhos Islands. Secondly, the unincorporated areas are A-class reserves either in, or close to. In Canada, depending on the province, a settlement is one that does not have a municipal council that governs solely over the settlement. It is usually, but not always, part of a municipal government. This can range from hamlets to large urbanized areas that are similar in size to towns. In British Columbia, unincorporated settlements lie outside municipal boundaries entirely, Unincorporated settlements with a population of between 100 and 1,000 residents may have the status of designated place in Canadian census data. In some provinces, large tracts of undeveloped wilderness or rural country are unorganized areas that fall directly under the provincial jurisdiction
4.
Miami-Dade County, Florida
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Miami-Dade County is a county located in the southeastern part of the U. S. state of Florida. It is the southeasternmost county on the U. S. mainland, according to a 2015 census report, the county had a population of 2,693,117, making it the most populous county in Florida and the seventh-most populous county in the United States. It is also Floridas third-largest county in terms of land area, Miami-Dade County is included in the Miami-Fort Lauderdale-West Palm Beach, FL Metropolitan Statistical Area. The county is home to 34 incorporated cities and many unincorporated areas, southern Miami-Dade County includes the Redland and Homestead areas, which make up the agricultural economy of Miami. Agricultural Redland makes up one third of Miami-Dade Countys inhabited land area, and is sparsely populated. The western portion of the county extends into the Everglades National Park and is populated only by a Miccosukee tribal village, East of the mainland in Biscayne Bay is also Biscayne National Park and the Biscayne Bay Aquatic Preserves. The earliest evidence of Native American settlement in the Miami region came from about 12,000 years ago, the first inhabitants settled on the banks of the Miami River, with the main villages on the northern banks. The Tequesta Indians fished, hunted, and gathered the fruit and roots of plants for food and they buried the small bones of the deceased with the rest of the body, and put the larger bones in a box for the village people to see. The Tequesta are credited with making the Miami Circle, Juan Ponce de León was the first European to visit the area in 1513 by sailing into Biscayne Bay. His journal records that he reached Chequescha, a varianth of Tequesta and it is unknown whether he came ashore or made contact with the natives. Pedro Menéndez de Avilés and his men made the first recorded landing when they visited the Tequesta settlement in 1566 while looking for Avilés missing son, shipwrecked a year earlier. Spanish soldiers led by Father Francisco Villarreal built a Jesuit mission at the mouth of the Miami River a year later, after the Spaniards left, the Tequesta Indians were left to fend themselves from European-introduced diseases like smallpox. By 1711, the Tequesta sent a couple of local chiefs to Havana, Cuba, the Cubans sent two ships to help them, but Spanish illnesses struck and most of the Indians died. The first permanent European settlers arrived in the early 19th century, people came from the Bahamas to South Florida and the Keys to hunt for treasure from the ships that ran aground on the treacherous Great Florida Reef. Some accepted Spanish land offers along the Miami River, at about the same time, the Seminole Indians arrived, along with a group of runaway slaves. The area was affected by the Second Seminole War, during which Major William S. Harney led several raids against the Indians, most non-Indian residents were soldiers stationed at Fort Dallas. It was the most devastating Indian war in American history, causing almost a total loss of population in Miami, after the Second Seminole War ended in 1842, William English, re-established a plantation started by his uncle on the Miami River. He charted the “Village of Miami” on the bank of the Miami River
5.
Edward Leedskalnin
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Leedskalnin was also known for developing theories of magnetism. Edward Leedskalnin was born on January 12,1887 in Stāmeriena parish, little is known of his childhood, aside from the fact that his parents were not wealthy, he received only a fourth-grade formal education. Edward was a boy who often spent time reading books. It was suggested that he learned stonemasonry from his father and practiced this craft in Latvia after coming of age, at the age of 26 he was engaged to marry Agnes Scuffs who was ten years younger. However, the girl who Leedskalnin later referred to as his Sweet Sixteen broke the engagement, on April 7,1912 Leedskalnin arrived in New York City. After looking for work at the East Coast till August, he relocated to the Pacific Northwest. On June 5,1917 he filled in his registration in Oregon stating that he was self-employed and engaged in ax-handle manufacturing. The 1920 census data reveal that he resided in Reedsport, Oregon, on February 27,1923 The Homestead Enterprise newspaper published a notice that E. Leedskalnin a Californian has purchased an acre of the R. L. Moser homestead and is planning to erect a home soon. Over the next 20 years, Leedskalnin constructed a structure that he called Rock Gate and dedicated, in his own words. He used various basic tools available under his modest means including salvaged timber, first, he built a house out of limestone blocks and wood, then he gradually constructed a stone structure for which he is now famous. Despite his reserved personality, he opened the Coral Castle to the public. On November 9,1951 he checked himself into Jackson Memorial Hospital in Miami, apparently, Leedskalnin suffered a stroke either before he left for the hospital or at the hospital. He died twenty-eight days later of pyelonephritis at the age of 64 and his death certificate noted that his death was a result of uremia, failure of kidneys, as a result of the infection and abscess. The Coral Castle During his lifetime Leedskalnin published five pamphlets on various subjects, the Author In the first section, Leedskalnin vents his anger at his Sweet Sixteen, arguing that girls should be kept pure, and that boys are primarily a soiling influence upon them. On page 4 of A Book in Every Home, Leedskalnin writes, Everything we do should be for good purpose. When a girl is sixteen or seventeen years old, she is as good as she ever will be, but when a boy is sixteen years old, he is then fresher than in all his stages of development. He is then not big enough to work but he is too big to be kept in a nursery, now I will tell you about soiling. The second section continues along the theme of education, with several aphorisms aimed at parents regarding the proper way to raise children
6.
Megalith
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A megalith is a large stone that has been used to construct a structure or monument, either alone or together with other stones. The word megalithic describes structures made of large stones without the use of mortar or concrete. For later periods, the monolith, with an overlapping meaning, is more likely to be used. The word megalith comes from the Ancient Greek μέγας and λίθος, megalith also denotes an item consisting of rock hewn in definite shapes for special purposes. It has been used to describe buildings built by people from parts of the world living in many different periods. A variety of stones are seen as megaliths, with the most widely known megaliths not being sepulchral. The construction of these took place mainly in the Neolithic and continued into the Chalcolithic. At a number of sites in eastern Turkey, large ceremonial complexes from the 9th millennium BC have been discovered and they belong to the incipient phases of agriculture and animal husbandry. Large circular structures involving carved megalithic orthostats are a feature, e. g. at Nevalı Çori. Although these structures are the most ancient megalithic structures known so far, at Göbekli Tepe, four stone circles have been excavated from an estimated 20. Some measure up to 30 metres across, as well as human figures, the stones carry a variety of carved reliefs depicting boars, foxes, lions, birds, snakes and scorpions. Dolmens and standing stones have been found in areas of the Middle East starting at the Turkish border in the north of Syria close to Aleppo. They can be encountered in Lebanon, Syria, Iran, Israel, Jordan, the largest concentration can be found in southern Syria and along the Jordan Rift Valley, however they are being threatened with destruction. They date from the late Chalcolithic/Early Bronze Age, megaliths have also been found on Kharg Island and pirazmian in Iran, at Barda Balka in Iraq, and at Jaintapur in Bangladesh. A semicircular arrangement of megaliths was found in Israel at Atlit Yam and it is a very early example, dating from the 7th millennium BC. The most concentrated occurrence of dolmens in particular is in an area on both sides of the Jordan Rift Valley, with greater predominance on the eastern side. They occur first and foremost on the Golan Heights, the Hauran, and in Jordan, in Saudi Arabia, only very few dolmen have been identified so far in the Hejaz. They seem, however, to re-emerge in Yemen in small numbers, the standing stone has a very ancient tradition in the Middle East, dating back from Mesopotamian times
7.
Limestone
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Limestone is a sedimentary rock, composed mainly of skeletal fragments of marine organisms such as coral, forams and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate, about 10% of sedimentary rocks are limestones. The solubility of limestone in water and weak acid solutions leads to karst landscapes, most cave systems are through limestone bedrock. The first geologist to distinguish limestone from dolomite was Belsazar Hacquet in 1778, like most other sedimentary rocks, most limestone is composed of grains. Most grains in limestone are skeletal fragments of organisms such as coral or foraminifera. Other carbonate grains comprising limestones are ooids, peloids, intraclasts and these organisms secrete shells made of aragonite or calcite, and leave these shells behind when they die. Limestone often contains variable amounts of silica in the form of chert or siliceous skeletal fragment, some limestones do not consist of grains at all, and are formed completely by the chemical precipitation of calcite or aragonite, i. e. travertine. Secondary calcite may be deposited by supersaturated meteoric waters and this produces speleothems, such as stalagmites and stalactites. Another form taken by calcite is oolitic limestone, which can be recognized by its granular appearance, the primary source of the calcite in limestone is most commonly marine organisms. Some of these organisms can construct mounds of rock known as reefs, below about 3,000 meters, water pressure and temperature conditions cause the dissolution of calcite to increase nonlinearly, so limestone typically does not form in deeper waters. Limestones may also form in lacustrine and evaporite depositional environments, calcite can be dissolved or precipitated by groundwater, depending on several factors, including the water temperature, pH, and dissolved ion concentrations. Calcite exhibits a characteristic called retrograde solubility, in which it becomes less soluble in water as the temperature increases. Impurities will cause limestones to exhibit different colors, especially with weathered surfaces, Limestone may be crystalline, clastic, granular, or massive, depending on the method of formation. Crystals of calcite, quartz, dolomite or barite may line small cavities in the rock, when conditions are right for precipitation, calcite forms mineral coatings that cement the existing rock grains together, or it can fill fractures. Travertine is a banded, compact variety of limestone formed along streams, particularly there are waterfalls. Calcium carbonate is deposited where evaporation of the leaves a solution supersaturated with the chemical constituents of calcite. Tufa, a porous or cellular variety of travertine, is found near waterfalls, coquina is a poorly consolidated limestone composed of pieces of coral or shells. During regional metamorphism that occurs during the building process, limestone recrystallizes into marble
8.
Coral
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Corals are marine invertebrates in the class Anthozoa of phylum Cnidaria. They typically live in colonies of many identical individual polyps. The group includes the important reef builders that inhabit tropical oceans, a coral group is a colony of myriad genetically identical polyps. Each polyp is an animal typically only a few millimeters in diameter. A set of tentacles surround a central mouth opening, an exoskeleton is excreted near the base. Over many generations, the colony creates a large skeleton that is characteristic of the species. Individual heads grow by reproduction of polyps. Corals also breed sexually by spawning, polyps of the same species release gametes simultaneously over a period of one to several nights around a full moon and these are commonly known as zooxanthellae and the corals that contain them are zooxanthellate corals. Such corals require sunlight and grow in clear, shallow water, other corals do not rely on zooxanthellae and can live in much deeper water, with the cold-water genus Lophelia surviving as deep as 3,000 metres. Some have been found on the Darwin Mounds, north-west of Cape Wrath, Corals have also been found as far north as off the coast of Washington State and the Aleutian Islands. In his Scala Naturae, Aristotle classified corals as zoophyta, animals that had characteristics of plants and were therefore hypothetically in between animals and plants, the Persian polymath Al-Biruni classified sponges and corals as animals, arguing that they respond to touch. The phylogeny of Anthozoans is not clearly understood and a number of different models have been proposed, within the Hexacorallia, the sea anemones, coral anemones and stony corals may constitute a monophyletic grouping united by their eight-fold symmetry and cnidocyte trait. The Octocorallia appears to be monophyletic, and primitive members of this group may have been stolonate, the cladogram presented here comes from a 2014 study by Stampar et al. which was based on the divergence of mitochondrial DNA within the group and on nuclear markers. Corals are classified in the class Anthozoa of the phylum Cnidaria and they are divided into three subclasses, Hexacorallia, Octocorallia, and Ceriantharia. The Hexacorallia include the stony corals, the sea anemones and the zoanthids and these groups have polyps that generally have 6-fold symmetry. The Octocorallia include blue coral, soft corals, sea pens and these groups have polyps with 8-fold symmetry, each polyp having eight tentacles and eight mesenteries. Fire corals are not true corals, being in the order Anthomedusa of the class Hydrozoa, Corals are sessile animals in the class Anthozoa and differ from most other cnidarians in not having a medusa stage in their life cycle. The body unit of the animal is a polyp, most corals are colonial, the initial polyp budding to produce another and the colony gradually developing from this small start
9.
Latvia
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Latvia, officially the Republic of Latvia, is a country in the Baltic region of Northern Europe, one of the three Baltic states. It is bordered by Estonia to the north, Lithuania to the south, Russia to the east, Latvia has 1,957,200 inhabitants and a territory of 64,589 km2. The country has a seasonal climate. Latvia is a parliamentary republic established in 1918. The capital city is Riga, the European Capital of Culture 2014, Latvia is a unitary state, divided into 119 administrative divisions, of which 110 are municipalities and 9 are cities. Latvians and Livs are the people of Latvia. Latvian and Lithuanian are the two surviving Baltic languages. Despite foreign rule from the 13th to 20th centuries, the Latvian nation maintained its identity throughout the generations via the language, Latvia and Estonia share a long common history. Until World War II, Latvia also had significant minorities of ethnic Germans, Latvia is historically predominantly Protestant Lutheran, except for the Latgale region in the southeast, which has historically been predominantly Roman Catholic. The Russian population has brought a significant portion of Eastern Orthodox Christians. The Republic of Latvia was founded on 18 November 1918, however, its de facto independence was interrupted at the outset of World War II. The peaceful Singing Revolution, starting in 1987, called for Baltic emancipation of Soviet rule and it ended with the Declaration on the Restoration of Independence of the Republic of Latvia on 4 May 1990, and restoring de facto independence on 21 August 1991. Latvia is a democratic and developed country and member of the European Union, NATO, the Council of Europe, the United Nations, CBSS, the IMF, NB8, NIB, OECD, OSCE, and WTO. For 2014, Latvia was listed 46th on the Human Development Index and it used the Latvian lats as its currency until it was replaced by the euro on 1 January 2014. The name Latvija is derived from the name of the ancient Latgalians, one of four Indo-European Baltic tribes, henry of Latvia coined the Latinisations of the countrys name, Lettigallia and Lethia, both derived from the Latgalians. The terms inspired the variations on the name in Romance languages from Letonia. Around 3000 BC, the ancestors of the Latvian people settled on the eastern coast of the Baltic Sea. The Balts established trade routes to Rome and Byzantium, trading local amber for precious metals, by 900 AD, four distinct Baltic tribes inhabited Latvia, Curonians, Latgalians, Selonians, Semigallians, as well as the Livonians speaking a Finnic language
10.
United States
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Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography, climate and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations. In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
11.
Hydrogen
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Hydrogen is a chemical element with chemical symbol H and atomic number 1. With a standard weight of circa 1.008, hydrogen is the lightest element on the periodic table. Its monatomic form is the most abundant chemical substance in the Universe, non-remnant stars are mainly composed of hydrogen in the plasma state. The most common isotope of hydrogen, termed protium, has one proton, the universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, since hydrogen readily forms covalent compounds with most nonmetallic elements, most of the hydrogen on Earth exists in molecular forms such as water or organic compounds. Hydrogen plays an important role in acid–base reactions because most acid-base reactions involve the exchange of protons between soluble molecules. In ionic compounds, hydrogen can take the form of a charge when it is known as a hydride. The hydrogen cation is written as though composed of a bare proton, Hydrogen gas was first artificially produced in the early 16th century by the reaction of acids on metals. Industrial production is mainly from steam reforming natural gas, and less often from more energy-intensive methods such as the electrolysis of water. Most hydrogen is used near the site of its production, the two largest uses being fossil fuel processing and ammonia production, mostly for the fertilizer market, Hydrogen is a concern in metallurgy as it can embrittle many metals, complicating the design of pipelines and storage tanks. Hydrogen gas is flammable and will burn in air at a very wide range of concentrations between 4% and 75% by volume. The enthalpy of combustion is −286 kJ/mol,2 H2 + O2 →2 H2O +572 kJ Hydrogen gas forms explosive mixtures with air in concentrations from 4–74%, the explosive reactions may be triggered by spark, heat, or sunlight. The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C, the detection of a burning hydrogen leak may require a flame detector, such leaks can be very dangerous. Hydrogen flames in other conditions are blue, resembling blue natural gas flames, the destruction of the Hindenburg airship was a notorious example of hydrogen combustion and the cause is still debated. The visible orange flames in that incident were the result of a mixture of hydrogen to oxygen combined with carbon compounds from the airship skin. H2 reacts with every oxidizing element, the ground state energy level of the electron in a hydrogen atom is −13.6 eV, which is equivalent to an ultraviolet photon of roughly 91 nm wavelength. The energy levels of hydrogen can be calculated fairly accurately using the Bohr model of the atom, however, the atomic electron and proton are held together by electromagnetic force, while planets and celestial objects are held by gravity. The most complicated treatments allow for the effects of special relativity
12.
Everglades
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The Everglades is a natural region of tropical wetlands in the southern portion of the U. S. state of Florida, comprising the southern half of a large drainage basin and part of the neotropic ecozone. The system begins near Orlando with the Kissimmee River, which discharges into the vast but shallow Lake Okeechobee. Water leaving the lake in the wet season forms a slow-moving river 60 miles wide, the Everglades experience a wide range of weather patterns, from frequent flooding in the wet season to drought in the dry season. Human habitation in the portion of the Florida peninsula dates to 15,000 years ago. Before European colonization, the region was dominated by the native Calusa, with Spanish colonization, both tribes declined gradually during the following two centuries. The Seminole formed from mostly Creek people who had been warring to the North, they assimilated other peoples and created a new culture. After being forced from northern Florida into the Everglades during the Seminole Wars of the early 19th century, migrants to the region who wanted to develop plantations first proposed draining the Everglades in 1848, but no work of this type was attempted until 1882. Canals were constructed throughout the first half of the 20th century, in 1947, Congress formed the Central and Southern Florida Flood Control Project, which built 1,400 miles of canals, levees, and water control devices. The Miami metropolitan area grew substantially at this time and Everglades water was diverted to cities, portions of the Everglades were transformed into farmland, where the primary crop was sugarcane. Approximately 50 percent of the original Everglades has been developed as agricultural or urban areas, following this period of rapid development and environmental degradation, the ecosystem began to receive notable attention from conservation groups in the 1970s. Internationally, UNESCO and the Ramsar Convention designated the Everglades a Wetland Area of Global Importance, the construction of a large airport 6 miles north of Everglades National Park was blocked when an environmental study found that it would severely damage the South Florida ecosystem. With heightened awareness and appreciation of the region, restoration began in the 1980s with the removal of a canal that had straightened the Kissimmee River, however, development and sustainability concerns have remained pertinent in the region. The deterioration of the Everglades, including water quality in Lake Okeechobee, was linked to the diminishing quality of life in South Floridas urban areas. In 2000 the Comprehensive Everglades Restoration Plan was approved by Congress to combat these problems, to date, it is the most expensive and comprehensive environmental restoration attempt in history, but its implementation has faced political complications. The first written record of the Everglades was on Spanish maps made by cartographers who had not seen the land and they named the unknown area between the Gulf and Atlantic coasts of Florida Laguna del Espíritu Santo. The area was featured on maps for decades without having been explored, British surveyor John Gerard de Brahm, who mapped the coast of Florida in 1773, called the area River Glades. Both Marjory Stoneman Douglas and linguist Wallace McMullen suggest that cartographers substituted Ever for River, the name Everglades first appeared on a map in 1823, although it was also spelled as Ever Glades as late as 1851. The Seminole call it Pa-hay-okee, meaning Grassy Water, the region was labeled Pa-hai-okee on an American military map from 1839, although it had earlier been called Ever Glades throughout the Second Seminole War
