Тишакова Татьяна Станиславовна канд хим н., ассистент; Левашова Ольга Леонидовна канд фарм н., ассистент; Савельева Елена Валерьевна ассистент. В сборнике представлены тезисы
DOLOMITE Sukhdeep Singh, group 17. Scientific adviser is Tatyana Tishakova
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DOLOMITESukhdeep Singh, group 17. Scientific adviser is Tatyana TishakovaDolomite is an anhydrous carbonate material composed of calcium magnesium carbonate. [CaMg(CO3)2] Sedimentary carbonate rocks with majority of concentration as dolomite are called Dolostone. It was first described by Carl Linnaeus in 1768 andnamed by Nicolas de Saussure in 1792 after De Dolomieuwho found it in 1791. Properties: Crystal structure – Trigonal-rhombohedral. Color – White, Tan, Gray to Pink. Crystal twinning present. Poor solubility in dilute HCl. It does not dissolve in dilute hydrochloric acid rapidly. Double carbonate with alternating structural arrangement of Calcium and Magnesium ions. Solid solution between dolomite, ankerite and kutnohorite. Iron gives yellow to brown tint and Manganese gives rosy pink color. Brittle, vitreous to pearly luster. White to pink fluorescence under UV light, triboluminescent. Uses: Flux for smelting of iron and steel. Float glass production. In horticulture, it is used as pH buffer and Magnesium source. In marine aquariums, it is used to help buffer changes in pH of water Motorcycle speedway tracks, concrete aggregates. It is used as covering for particle detectors as it has minor quantities of radioactive material and can shield against cosmic radiation without adding to background radiation levels. Source of magnesium oxide in Pidgeon process. Dolomite can be used as a calcium supplement but unregulated doses can cause complications. AMETHYSTAshish Joseph, group 19. Scientific adviser is Tatyana TishakovaAmethyst is a violet variety of quartz often used in jewellery. The ancient Greeks wore amethyst and made drinking vessels of it in the belief that it would prevent intoxification. Amethyst is a semiprecious stone and is the traditional birthstone for February. Amethyst owes its violet colour to irradiation, iron impurities, transition elements, and the presence of trace elements, which result in complex crystal lattice substitution. The hardness of the mineral is the same as quartz, thus it is suitable for use in jewellery. Synthetic amethyst is produced by gamma-rays, X-ray or electron beam irradiation of clear quartz which has been first doped with ferric impurities. On exposure to heat, the irradiation effects can be partially cancelled and amethyst generally becomes yellow or even green, and much of the citrine, cairngorm, or yellow quartz of jewellery is said to be merely "burnt amethyst”. Brandberg Amethyst, Chevron Amethyst, Ametrine,”Rutilated” Amethyst are different types of Amethyst found around the world. Amethyst is one of the most effective crystals for healing people, plants and animals. Natural unpolished Amethysts or geodes are particularly helpful placed where plants will not grow or animals refuse to sit. It also counteracts negative earth energies beneath buildings or anywhere that feels hostile. Referred to as “nature’s tranquilizer,” Amethyst calms and soothes, assisting the transmission of neural signals through the brain. It relieves obsessive compulsive disorder and hyperactivity in children and animals. Place under the pillow or mattress, or rub the center of the forehead counter-clockwise to cure insomnia and stimulate pleasant dreams. It is especially effective for children’s recurring nightmares and fears of the dark, and may help alleviate homesickness. Amethyst boosts the production of hormones, and stimulates the sympathetic nervous system and endocrine glands to optimum performance. It supports oxygenation in the blood, and aids in treatments of the digestive tract, heart, stomach, and skin. Amethyst also strengthens the immune system and reduces bruising, pain and swellings. It has been used with excellent results as an elixir in the treatment of arthritis. Amethyst is thought to relieve the symptoms of tinnitus and other hearing disorders, and is highly beneficial in treating insomnia, especially when caused by an overactive mind. It is calming and soothing to the neural impulses in the brain. Its energy ameliorates the pain of headaches and migraines, and reduces stress and nervous tension. It may be used to treat psychic disturbances and to stabilize brain imbalances, but should not be used in cases of paranoia or schizophrenia. Amethyst is produced in abundance from the state of Minas Gerais in Brazil where it occurs in large geodes within volcanic rocks. It is also found and mined in South Korea. . Much fine amethyst comes from Russia. Many localities in south India yield amethyst. One of the largest global amethyst producers is Zambia in southern Africa.
Harish Kumar Naik, group19. Scientific adviser is Tatyana Tishakova• Catarory – Silicate Mineral. • Strunz – 09.DP.20 • Crystal – Orthorhombic-Pyramidal • Specific Gravity – 2.8–2.95 • Fluorescence – White mild peach, Long UV=yellow Prehnite is a inosilicate of calcium and aluminium with the formula: Ca2Al(AlSi3O10)(OH)2. Limited Fe3+ substitutes for aluminium in the structure.Prehnite crystallizes in the orthorhombic crystal system, and most oftens forms as stalactitic or botryoidal aggregates, with only just the crests of small crystals showing any faces, which are almost always curved or composite. Very rarely will it form distinct, well individualized crystals showing a square-like cross-section, like those found at the Jeffrey Mine in Asbestos, Quebec, Canada. It was first described in 1788 for an occurrence in the Karoo dolerites of Cradock, Eastern Cape Province, South Africa.It was named for ColonelHendrik Von Prehn (1733–1785), commander of the military forces of theDutch colony at the Cape of Good Hope from 1768 to 1780. Prehnite is a highly desired mineral among collectors, especially intriguing well-shaped form and pseudomorphs. Prehnite is used as a minor gemstone. One of its strongest assets is to put you in touch with beings in spirit. It will help you to learn to be psychic...and it is very useful used in meditation. жүктеу/скачать 1.64 Mb. Достарыңызбен бөлісу:
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