|
Sand Flat, Van Zandt County, Texas
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass. The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non- tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz. Calcium carbonate is the second most common type of sand, for example, aragonite, which has mostly been created, over the past 500million years, by various forms of life, like coral and shellfish. For example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Somewhat more rarely, sand may be composed o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Libya 4608 Idehan Ubari Dunes Luca Galuzzi 2007
Libya (; ar, ليبيا, Lībiyā), officially the State of Libya ( ar, دولة ليبيا, Dawlat Lībiyā), is a country in the Maghreb region in North Africa. It is bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad to the south, Niger to the southwest, Algeria to the west, and Tunisia to the northwest. Libya is made of three historical regions: Tripolitania, Fezzan, and Cyrenaica. With an area of almost 700,000 square miles (1.8 million km2), it is the fourth-largest country in Africa and the Arab world, and the 16th-largest in the world. Libya has the 10th-largest proven oil reserves in the world. The largest city and capital, Tripoli, is located in western Libya and contains over three million of Libya's seven million people. Libya has been inhabited by Berbers since the late Bronze Age as descendants from Iberomaurusian and Capsian cultures. In ancient times, the Phoenicians established city-states and trading posts i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. Alabaster, a fine-grained white or lightly tinted variety of gypsum, has been used for sculpture by many cultures including Ancient Egypt, Mesopotamia, Ancient Rome, the Byzantine Empire, and the Nottingham alabasters of Medieval England. Gypsum also crystallizes as translucent crystals of selenite. It forms as an evaporite mineral and as a hydration product of anhydrite. The Mohs scale of mineral hardness defines gypsum as hardness value 2 based on scratch hardness comparison. Etymology and history The word ''gypsum'' is derived from the Greek word (), "plaster". Because the quarries of the Montmartre district of Paris have long furnished burnt gypsum (calcined gypsum) used for various purposes, this dehydrated gypsum became known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Atterberg
Albert Mauritz Atterberg (19 March 1846 – 4 April 1916) was a Swedish chemist and agricultural scientist who created the Atterberg limits, which are commonly referred to by geotechnical engineers and engineering geologists today. In Sweden he is equally known for creating the Atterberg grainsize scale, which remains the one in use. Atterberg received his Ph.D. in chemistry from Uppsala University in 1872 and then stayed there as a lecturer in analytical chemistry until 1877, during which time he traveled across Sweden and abroad to study the latest developments in organic chemistry. He then went on to become the principal of the Chemical Station and Seed Control Institute at Kalmar, publishing numerous papers on agricultural research dealing with the classification of varieties of oats and corn between 1891 and 1900. It was towards the age of fifty-four that Atterberg, while continuing his work on chemistry, began to focus his efforts on the classification and plasticity of so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Springer Verlag
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second largest academic publisher with 65 staff in 1872.Chronology ". Springer Science+Business Media. In 1964, Springer expanded its business internationally, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
