The,nature,and,purpose,element business, insurance The nature and purpose of elemental boron
Small offices have unique needs, and thatincludes document shredding. Designed with the smaller business inmind, the Dahle 20314 is a cross-cut shredder that offers Level 3security and brings you into compliance with federal regulations. The As we all know to live in this world we have to perform some activity by which we can earn money. There are many activities by which we can earn money and meet the standards to live in this society. And from one of them is franchise. Franc
The natural boron has two isotopes:boron 10 and boron 11, boron 10 is the most important. Boron is non-metallic element.Elemental boron has amorphous boron powder andcrystalline boron two kinds. The former is brownish black to black powder; the latterwas jet-black to silver-gray, remarkable metallic luster, close to the hardnessof diamond, but there is a very high resistance, the electrical conductivityincreases with the increasing temperature. Amorphous boron powder density is 2.3 g / cm 3 (25-27 ° C); crystallineelemental boron density is 2.31 g / cm 3. Boronsmelting point is 2300°C,boiling point is 2550°C.Boron has extensive application. Boron in combination with plastic or aluminumis an effective neutron shielding material; boron steel used in the reactor asa control rod; boron fibers for manufacturing a composite material and so on.Boron is relatively stable at roomtemperature, even long-term boiling in hydrochloric acid or hydrofluoric aciddoes not work. Boron can combine with halogen group elements to form a boronhalide. Boron in 600 ~ 1000°Ccan react with sulfur, tin, phosphorus, arsenic; in 1000 to 1400°C, react with the nitrogen, carbon,silicon effects, under high temperature boron also react with many metals andmetal oxides, formed metal borides. These compounds are generally with high hardness,resistance to melt, high electrical conductivity, and chemically inertsubstances, often with special properties. 1702 French doctors first from boraxmade of boric acid, called sedation salt. In 1741, French chemist pointedout that the borax react with sulfuric acid not only get boric acid, but alsoget sodium. In 1789, scientists included boric acid group in the table ofelements. 1808 British chemist and France chemist use potassium torestore boric acid obtained boron.Amorphous boron powder at room temperatureoxidized in air slowly, at about 800can be spontaneous firing. Boron with hydrochloric acid or hydrofluoric acid,even though long-term boiling could not react. It can be slow eroded and oxidizedby a mixture of hot concentrated nitric acid and sodium dichromate and sulfuricacid. Hydrogen peroxide and ammonium persulfate also can be slow oxidizedcrystalline boron. These reagents react with amorphous boron is fierce.Eutectic with the alkali metal carbonates and hydroxides mixture, all thevarious forms of boron are completely oxidized. Chlorine, bromine, fluorine reactwith boron to form the corresponding boron halide. Boron and sulfur intense reactionat 600 to form a sulfurized boron mixture. Boronin a nitrogen or ammonia gas heated to above 1000can form boron nitride, above 1800-2000boron and hydrogen is still not react, boron and silicon above2000 can react to generate boride silicon. At high temperatures, theboron can react with many metal powder and metal oxides to generatemetal boride.Boron is mainly used in metallurgy (eg, inorder to increase the hardness of steel) produce borax and boric acid andelemental boron, because it absorb neutrons ability is strong. Boron at hightemperatures is particularly lively, so it was used for metallurgical heattreatment getter, wrought iron heated process, increased high temperature alloysteel rugged, boron is also used in nuclear reactors and high-temperaturetechnology. Rod and strip boron steel is widely used as control rods in anuclear reactor. Due to the nature of boron has low density, high strength anda high melting point, it can be used to produce some of the structuralmaterials in missile rocket. Boron compounds in agriculture, medicine, glassindustry is widely used. Therefore, boron resources development, utilization,for the development of modern industry has an increasingly important role.Source:http://www.mhcmp.com
The,nature,and,purpose,element