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Gwihabaite
Gwihabaite is a rare ammonium potassium nitrate mineral (NH4,K)(NO3). It is orthorhombic in form, colorless with a vitreous luster. It has a Mohs hardness of 5 and a specific gravity of 1.77. It is deliquescent and water-soluble. The mineral is also known as ''nitrammite''. It was first described in 1996 for an occurrence in Gcwihaba Caves (Drotsky's Cavern, type locality), Maun, North-West District, Botswana. The spelling of the name was simplified, omitting the "c", which represents the "click" sound used by the San people. It occurs as incrustations and efflorescences on cave surfaces formed by bacterial action on bat guano Guano (Spanish from qu, wanu) is the accumulated excrement of seabirds or bats. As a manure, guano is a highly effective fertilizer due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. .... References {{mineral-stub Nitrate minerals Orthorhombic minerals Minerals in space group 62 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gcwihaba
Gcwihaba is a cave in Botswana located in Okavango Delta region. The Gcwihaba Caves were part of the Kalahari landscape around 2 million years ago, at least for the entire period of the Pleistocene. The name of the cave is a San word and stands for "hyena's lair". The cave is situated 10 km away from the Namibian border. In 1932 it was first shown to a European, Ghanzi region farmer Martinus Drotsky, and the main cavern was named Drotsky's cavern after him. Gwchihaba is a Botswana National Monument under the Monuments, Relics and Antiquities Act, and has been put forward to become a UNESCO World Heritage Site in 1999. It is the type locality of the mineral gwihabaite (IMA1994-011). Even though nothing was found in the first 50 cm of cave during the excavations to affirm that the cave was settled as a camp, 51 stone artefacts (33 of them made from travertine) were released in the upper 50 cm of the cave. 50–80 cm of the cave is called The Terminal Pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium
The ammonium cation is a positively-charged polyatomic ion with the chemical formula or . It is formed by the protonation of ammonia (). Ammonium is also a general name for positively charged or protonated substituted amines and quaternary ammonium cations (), where one or more hydrogen atoms are replaced by organic groups (indicated by R). Acid–base properties The ammonium ion is generated when ammonia, a weak base, reacts with Brønsted acids (proton donors): :H+ + NH3 -> H4 The ammonium ion is mildly acidic, reacting with Brønsted bases to return to the uncharged ammonia molecule: : H4 + B- -> HB + NH3 Thus, treatment of concentrated solutions of ammonium salts with strong base gives ammonia. When ammonia is dissolved in water, a tiny amount of it converts to ammonium ions: :H2O + NH3 OH- + H4 The degree to which ammonia forms the ammonium ion depends on the pH of the solution. If the pH is low, the equilibrium shifts to the right: more ammonia molecules are co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Botswana
Botswana (, ), officially the Republic of Botswana ( tn, Lefatshe la Botswana, label=Setswana, ), is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory being the Kalahari Desert. It is bordered by South Africa to the south and southeast, Namibia to the west and north, and Zimbabwe to the northeast. It is connected to Zambia across the short Zambezi River border by the Kazungula Bridge. A country of slightly over 2.3 million people, Botswana is one of the most sparsely populated countries in the world. About 11.6 percent of the population lives in the capital and largest city, Gaborone. Formerly one of the world's poorest countries—with a GDP per capita of about US$70 per year in the late 1960s—it has since transformed itself into an upper-middle-income country, with one of the world's fastest-growing economies. Modern-day humans first inhabited the country over 200,000 years ago. The Tswana ethnic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrate Minerals
Nitrate is a polyatomic ion with the chemical formula . Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate. Structure The ion is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a formal charge of −1. This charge results from a combination formal charge in which each of the three oxygens carries a − charge, whereas the nitrogen carries a +1 charge, all these adding up to formal charge of the polyatomic nitrate ion. This arrangement is commonly used as an example of resonance. Like the isoelectronic carbonate ion, the nitrate ion can be represented by resonance structures: Dietary nitrate A rich source of inorganic nitrate in the human diets come from leafy green foods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bat Guano
Guano (Spanish from qu, wanu) is the accumulated excrement of seabirds or bats. As a manure, guano is a highly effective fertilizer due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. Guano was also, to a lesser extent, sought for the production of gunpowder and other explosive materials. The 19th-century seabird guano trade played a pivotal role in the development of modern input-intensive farming. The demand for guano spurred the human colonization of remote bird islands in many parts of the world. Unsustainable seabird guano mining processes can result in permanent habitat destruction and the loss of millions of seabirds. Bat guano is found in caves throughout the world. Many cave ecosystems are wholly dependent on bats to provide nutrients via their guano which supports bacteria, fungi, invertebrates, and vertebrates. The loss of bats from a cave can result in the extinction of species that rely on their guano. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea caves, rock shelters, and grottos, that extend a relatively short distance into the rock and they are called ''exogene'' caves. Caves which extend further underground than the opening is wide are called ''endogene'' caves. Speleology is the science of exploration and study of all aspects of caves and the cave environment. Visiting or exploring caves for recreation may be called ''caving'', ''potholing'', or ''spelunking''. Formation types The formation and development of caves is known as ''speleogenesis''; it can occur over the course of millions of years. Caves can range widely in size, and are formed by various geological processes. These may involve a combination of chemical processes, erosion by water, tectonic forces, microorgani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Efflorescence
In chemistry, efflorescence (which means "to flower out" in French) is the migration of a salt to the surface of a porous material, where it forms a coating. The essential process involves the dissolving of an internally held salt in water, or occasionally in another solvent. The water, with the salt now held in solution, migrates to the surface, then evaporates, leaving a coating of the salt. In what has been described as "primary efflorescence", the water is the invader and the salt was already present internally, and a reverse process, where the salt is originally present externally and is then carried inside in solution, is referred to as "secondary efflorescence". Efflorescences can occur in natural and built environments. On porous construction materials it may present a cosmetic outer problem only (primary efflorescence causing staining), but can sometimes indicate internal structural weakness (migration/degradation of component materials). Efflorescence may clog the po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San People
The San peoples (also Saan), or Bushmen, are members of various Khoe, Tuu, or Kxʼa-speaking indigenous hunter-gatherer cultures that are the first cultures of Southern Africa, and whose territories span Botswana, Namibia, Angola, Zambia, Zimbabwe, Lesotho and South Africa. In 2017, Botswana was home to approximately 63,500 San people (roughly 2.8% of the population) making it the country with the highest number of San people. Definition The term "San" has a long vowel and is spelled Sān (in Khoekhoegowab orthography). It is a Khoekhoe exonym with the meaning of "foragers" and was often used in a derogatory manner to describe nomadic, foraging people. Based on observation of lifestyle, this term has been applied to speakers of three distinct language families living between the Okavango River in Botswana and Etosha National Park in northwestern Namibia, extending up into southern Angola; central peoples of most of Namibia and Botswana, extending into Zambia and Zimbabwe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Click Language
Click consonants, or clicks, are speech sounds that occur as consonants in many languages of Southern Africa and in three languages of East Africa. Examples familiar to English-speakers are the '' tut-tut'' (British spelling) or '' tsk! tsk!'' (American spelling) used to express disapproval or pity, the '' tchick!'' used to spur on a horse, and the '' clip-clop!'' sound children make with their tongue to imitate a horse trotting. Anatomically, clicks are obstruents articulated with two closures (points of contact) in the mouth, one forward and one at the back. The enclosed pocket of air is rarefied by a sucking action of the tongue (in technical terminology, clicks have a lingual ingressive airstream mechanism). The forward closure is then released,This is the case for all clicks used as consonants in words. Paralinguistically, however, there are other methods of making clicks: ''under'' the tongue or as above but by releasing the rear occlusion first. See #Places of articul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maun, Botswana
Maun is the fifth-largest town in Botswana. As of 2011, it had a population of 55,784. Maun is the "tourism capital" of Botswana and the administrative centre of Ngamiland district. Francistown and Maun are linked by the A3 highway. It is also the headquarters of numerous safari and air-charter operations who run trips into the Okavango Delta. Although officially still a village, Maun has developed rapidly from a rural frontier town and has spread along the Thamalakane River. It now has shopping centres, hotels and lodges as well as car hire, although it retains a rural atmosphere and local tribesmen continue to bring their cattle to Maun to sell. The community is distributed along the wide banks of the Thamalakane River where red lechwe can still be seen grazing next to local donkeys, goats and cattle. History The settlement was founded in 1915 as the tribal capital of the Batawana people, it has had a reputation as a hard-living 'Wild West' town helping the local cattle ran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North-West District (Botswana)
The North-West District or Ngamiland is one of the first-level administrative subdivisions of Botswana. For census and administrative purposes Ngamiland is subdivided into Ngamiland East, Ngamiland West and Ngamiland Delta (Okavango). It is governed by a District Commissioner, appointed by the national government, and the elected North-West District Council. The administrative centre is Maun. As of 2011, the total population of the district was 175,631 compared to 142,970 in 2001. The growth rate of population during the decade was 2.08. The total number of workers constituted 32,471 with 16,852 males and 15,621 females, with a majority of them involved in agriculture. Maun, the Tsodilo Hills, the Moremi Game Reserve, the Gchwihaba (Drotsky's) Caves, the Aha Hills (on the border with Namibia), the Nhabe Museum in Maun, and Maun Educational Park are the major tourist attractions in the district. History In the late 18th century, the Tswana people, primarily herders, began exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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