Sand

Sand is an example of a class of materials called granular matter. Sand is a obviously occurring, finely divided rock, comprising particles or granules ranging in size from 1/16 to 2 millimeters. An individual element in this range size is termed a sand grain. The next smaller size class in geology is silt: particles below 1/16 mm down to 1/256 mm (0.004 mm) in size. The next larger size class above sand is gravel, with particles ranging up to 64 mm The most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide), usually in the form of quartz which because of its chemical inertness and substantial hardness is quite resistant to weathering. However, the composition of sand varies according to local rock sources and conditions. The bright white sands found in tropical and subtropical coastal settings are ground-up limestone. Arkose is a sand or sandstone with considerable feldspar content which is derived from the weathering and erosion of a usually nearby granite. Some locations have sands that have magnetite, chlorite, glauconite, or gypsum. Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts. The chlorite-glauconite bearing sands are typically green in color, as are sands derived from basalts (lavas) with a high olivine content. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, white color. Sand deposits in some areas contain garnets and other resistant minerals, including some small gemstones.
Sand is transported by wind or water and deposited in the form of beaches, dunes, sand spits, sand bars, and the like. In most deserts, sand is a dominant constituent of the soil.
The study of sand is called arenology.

Mainframe computer

Mainframes are large and "expensive" computers used mainly by government institutions and large companies for mission critical applications, characteristically bulk data processing such as censuses, industry/consumer statistics, ERP, and financial transaction processing.
The term originated through the early 1970s with the introduction of smaller, less complex computers such as the DEC PDP-8 and PDP-11 series, which became known as minicomputers or just minis. The industry/users then coined the term "mainframe" to describe larger, earlier types (previously known simply as "computers").
Modern mainframe computers contain abilities not so much defined by their performance capabilities as by their high-quality internal engineering and resulting proven reliability, expensive but high-quality technical support, top-notch security, and strict backward compatibility for older software. These machines can and do run successfully for years with no interruption, with repairs taking place whilst they continue to run. Mainframe vendors offer such services as off-site redundancy — if a machine does break down, the vendor offers the option to run customers' applications on their own machines (often without users even noticing the change) whilst repairs go on.

Polymer

A polymer is a general term used to explain a substantially long molecule. This long molecule consists of structural units and repeating units strung together throughout chemical bonds. The process of converting these units to a polymer is called polymerization. These units are called monomers, which are characteristically small molecules of low molecular weight.
The monomers can be identical, or they can have one or more substituted chemical groups. These differences between monomers can have an effect on properties such as solubility, flexibility, or strength. In proteins, these differences can give the polymer the ability to preferentially adopt one conformation over another, as opposed to adopting a random coil (see self-assembly). Although most polymers are organic (based on carbon chains), there are also inorganic polymers, mainly based on a silicon backbone.
The term polymer covers a large, diverse group of molecules, including substances from proteins to high-strength kevlar fibres. A key feature that distinguishes polymers from other large molecules is the repetition of units of atoms (monomers) in their chains. This occurs during polymerization, in which many monomer molecules link to each other.

Geography of Aruba

Aruba is an island in the Caribbean Sea, just a short distance north of the Venezuelan Paraguaná Peninsula, and it forms a part of the Kingdom of the Netherlands. Unlike much of the Caribbean region, it has a dry climate and an arid, cactus-strewn landscape. This climate has helped tourism, however, as visitors to the island can consistently expect warm, sunny weather
Aruba is a generally flat, riverless island famous for its white sand beaches. Most of these are situated on the western and southern coasts of the island, which are comparatively sheltered from fierce ocean currents. The northern and eastern coasts, absence of this protection, are significantly more battered by the sea and have been left largely untouched by humans. The center of the island features some rolling hills, the better two of which are called Hooiberg at 165 m (541 ft) and Mount Jamanota, which is the uppermost on the island, at 188 m (617 ft) above sea level.
As a separate part of the Kingdom of the Netherlands, the island has no administrative subdivisions. On the east are Curaçao and Bonaire, which form the southwest part of the Netherlands Antilles; the three islands are well-known collectively as the ABC islands.
The local climate is a pleasant tropical marine clime. Little seasonal temperature difference exists, which helps Aruba to attract tourists all year round. Temperatures are almost constant at about 28 degrees Celsius (85 degrees Fahrenheit), moderated by constant trade winds from the Atlantic Ocean. Yearly precipitation barely reaches 500 mm (20 inches), the majority of it falling in late autumn.

Ice

Ice is the name given to any one of the 14 known solid phases of water. However, in non-scientific contexts, it usually describes ice Ih , which is the most abundant of these phases in Earth's biosphere. This type of ice is a soft, delicate, crystalline solid, which can appear transparent or an opaque bluish-white color depending on the presence of impurities such as air. The addition of other materials such as soil may further alter appearance. The most general phase transition to ice Ih occurs when liquid water is cooled below 0 °C (273.15 K, 32 °F) at standard atmospheric pressure. However, it can also deposit from a vapor with no intervening liquid phase such as in the creation of frost. Ice appears in various forms such as hail, ice cubes, and glaciers. It plays an important role with many meteorological phenomena. The ice caps of the polar regions are of significance for the global climate and mainly the water cycle.

Amazon Rainforest

From the east of the Andes, the Amazon Rainforest begins. It is the biggest rainforest in the world and is of great ecological significance, as its biomass is capable of absorbing enormous amounts of carbon dioxide. Conservation of the Amazon Rainforest has been a main issue in recent years.
The rainforest is supported by the extremely wet climate of the Amazon basin. The Amazon, and its hundreds of tributaries, flow gradually across the landscape, with an enormously shallow gradient sending them towards the sea: Manaus, 1,600 km (1,000 mi) from the Atlantic, is only 44 m (144 ft) above sea level.
The biodiversity within the rainforest is extraordinary: the region is home to at least 2.5 million insect species, tens of thousands of plants, and some 2,000 birds and mammals. One fifth of all the world's species of birds can be found in the Amazon rainforest.
The diversity of plant species in the Amazon basin is the highest on Earth. Some experts estimate that one square kilometre may contain over 75,000 types of trees and 150,000 species of higher plants. One square kilometre of Amazon rainforest can contain about 90,000 tons of living plants.

Morello Cherry

The Sour Cherry or Morello Cherry, (Prunus cerasus) is a class of Prunus in the subgenus Cerasus (cherries), native to much of Europe and southwest Asia. It is closely related to the Wild Cherry (P. avium), also known as sweet cherry, but has a fruit which is more acidic, and so is useful mainly for culinary purposes.
The tree is smaller than the Wild Cherry, increasing up to 4-10 m tall, and has twiggy branches, whilst the crimson to black fruit is borne on shorter stalks.
Sour Cherries require comparable cultivation conditions to pears, that is, they prefer a rich, well-drained moist soil, although they demand more nitrogen and water than sweet cherries. Trees will do badly if waterlogged, but have larger tolerance of poor drainage than sweet varieties. As with sweet cherries, Morellos are usually cultivated by budding onto strong growing rootstocks, which produce trees too large for most gardens, although newer dwarfing rootstocks such as Colt and Gisella are now available. During spring, flowers should be sheltered, and trees weeded, mulched and sprayed with seaweed solution. This is also the time when any required pruning should be carried out (note that cherries should not be pruned during the dormant winter months). Morello cherry trees fruit on younger wood than sweet varieties, and thus can be pruned harder. They are usually grown as standards, but can be fan trained, cropping well even on cold walls, or grown as low bushes.