Desalination

Desalination refers to any of several processes that take away the excess salt and other minerals from water in order to obtain fresh water fit for animal consumption or irrigation, and if almost all of the salt is removed, for human consumption, sometimes producing table salt as a by-product. Desalination of brackish water is previously commonplace in the U.S., where it is used to meet treaty obligations for river water
entering Mexico. Indeed, desalination has spread into use in over a hundred countries, with Saudi Arabia accounting for about 24% of total world capacity. Kuwait built the world's first large-scale desalination plant in the 1960s. Kuwait's energy reserves are so great that Kuwait is unique in using desalinated water for agriculture. The world's largest desalination plant is in Ashkelon, Israel. It began in use on August 4, 2005, and it is capable of producing 100 million cubic meters of water per year.

Mercury (element)

Mercury also called quicksilver, is a chemical component in the periodic table that has the symbol Hg (Latinized Greek: hydrargyrum, meaning watery or liquid silver) and atomic number 80. A important, silvery transition metal, mercury is one of five elements that are liquid at or near standard room temperature and pressure (the others are the metals caesium, francium, and gallium, and the nonmetal bromine). Mercury is used in thermometers, barometers and other scientific apparatus, although the use of mercury in thermometers has been mostly phased out in clinical and scientific environments (in favor of alcohol-filled, digital or thermistor-based replacements) due to concerns about the element's toxicity. Mercury is still used in dental amalgam. Mercury is frequently obtained by reduction from the mineral cinnabar. Mercury, like lead, is a neurotoxin, and elevated blood mercury levels have led to retardation and deformities in children.

Massive stars

During their helium-burning phase, very high mass stars with more than nine solar masses increased to form red supergiants. Once this fuel is exhausted at the core, they can carry on to fuse elements heavier than helium. The core contracts until the temperature and pressure are enough to fuse carbon. This process continues, with the consecutive stages being fueled by oxygen, neon, silicon, and sulfur. Near the end of the star's life, fusion can occur along a series of onion-layer shells within the star. Each shell fuses a different element, with the outermost shell fusing hydrogen; the next shell fusing helium, and so forth.The final stage is reached when the star begins producing iron. Since iron nuclei are more tightly bound than any heavier nuclei, if they are fused they do not release energy — the process would, on the contrary, consume energy. Likewise, since they are more tightly bound than all lighter nuclei, energy cannot be free by fission.In relatively old, very massive stars, a large core of inert iron will accumulate in the center of the star. The heavier elements in these stars can work their way up to the surface, forming evolved objects known as Wolf-Rayet stars that have a dense stellar wind which sheds the outer atmosphere.

gold

Gold is a extremely sought-after valuable metal that for many centuries has been used as money, a store of value and in ornaments. The metal occurs as nugget or grains in rocks and in alluvial deposits and is one of the coinage metals. It is a soft, glossy, yellow, dense, malleable, and ductile (trivalent and univalent) change metal. Modern manufacturing uses include dentistry and electronics. Gold forms the basis for a financial typical used by the International Monetary Fund (IMF) and the Bank for International resolution (BIS). Its ISO currency code is XAU.
Gold is a tinny element with a trait yellow color, but can also be black or ruby when finely alienated, while colloidal solutions are intensely tinted and often purple. These colors are the effect of gold's plasmon frequency lying in the visible range, which causes red and yellow glow to be reflected, and blue light to be engrossed. Only silver colloids show the same interactions with light, albeit at a shorter occurrence, making silver colloids yellow in color.
Gold is a good conductor of temperature and electricity, and is not precious by air and most reagents. Heat, damp, oxygen, and most corrosive agents have very little chemical effect on gold, making it well-suited for use in coins and jewelry; equally, halogens will chemically alter gold, and aqua regia dissolve it.
Pure gold is too soft for ordinary use and is hard-boiled by alloying with silver, copper, and other metals. Gold and its lots of alloys are most often used in jewelry, coinage and as a typical for monetary exchange in various countries. When promotion it in the form of jewelry, gold is calculated in karats (k), with pure gold being 24k. However, it is more commonly sold in lower capacity of 22k, 18k, and 14k. A lower "k" indicates a higher percent of copper or silver assorted into the alloy, with copper being the more typically used metal between the two. Fourteen karat gold-copper alloy will be almost identical in color to definite bronze alloys, and both may be used to produce polish and added badges. Eighteen karat gold with a high copper content is establish in some traditional jewelry and will have a distinct, though not dominant copper cast, giving an attractively warm color. A comparable karat weight when alloyed with silvery metals will appear less humid in color, and some low karat white metal alloys may be sold as "white gold", silvery in exterior with a slightly yellow cast but far more resistant to decay than silver or sterling silver. Karat weights of twenty and higher is more general in modern jewelry. Because of its high electrical conductivity and confrontation to decay and other desirable combinations of physical and chemical properties, gold also emerged in the late 20th century as an vital industrial metal, particularly as thin plating on electrical card associates and connectors.