Steam locomotive

A steam locomotive is a railway locomotive that produces its pulling power through a steam engine. These locomotives are fueled by burning combustible material—usually coal, wood, or oil—to produce steam in a boiler. The steam moves reciprocating pistons which are mechanically connected to the locomotive's main wheels (drivers). Both fuel and water supplies are carried with the locomotive, either on the locomotive itself or in wagons (tenders) pulled behind. The first steam locomotive, made by Richard Trevithick, first operated on 21 February 1804, three years after the road locomotive he made in 1801.

Steam locomotives were first developed in Great Britain during the early 19th century and dominated railway transport until the middle of the 20th century. From the early 1900s they were gradually superseded by electric and diesel locomotives, with full conversions to electric and diesel power beginning from the 1930s. The majority of steam locomotives were retired from regular service by the 1980s, though several continue to run on tourist and heritage lines.

Steam

Steam is water in the gas phase, which is formed when water boils. Steam is invisible; however, "steam" often refers to wet steam, the visible mist or aerosol of water droplets formed as this water vapor condenses. At lower pressures, such as in the upper atmosphere or at the top of high mountains, water boils at a lower temperature than the nominal 100 °C (212 °F) at standard temperature and pressure. If heated further it becomes superheated steam.

The enthalpy of vaporization is the energy required to turn water into the gaseous form when it increases in volume by 1,700 times at standard temperature and pressure; this change in volume can be converted into mechanical work by steam engines such as reciprocating piston type engines and steam turbines, which are a sub-group of steam engines. Piston type steam engines played a central role to the Industrial Revolution and modern steam turbines are used to generate more than 80% of the world's electricity. If liquid water comes in contact with a very hot surface or depressurizes quickly below its vapor pressure, it can create a steam explosion. Steam explosions have been responsible for many foundry accidents, and may also have been responsible for much of the damage to the plant in the Chernobyl disaster.

Zki & Dobre

HIDDEN ERROR: Usage of "Official_website" is not recognized

Zki & Dobre, known by many aliases, but currently most well known as Chocolate Puma (alternatively as The Good Men and as The Goodmen), are a Dutch house music duo from Haarlem, Netherlands. They comprise Gaston Steenkist ("Dobre") and René ter Horst ("DJ Zki"). They have produced multiple dance hits under various group names since the early 1990s. Their biggest international hits remains "Give It Up in 1993 credited as The Good Men and "Who Do You Love Now?" in 2001 credited to Riva featuring Dannii Minogue. They also founded their own record label Pssst Music.

Career

As the Goodmen, their biggest hit was "Give It Up", a 1993 house music track based upon samba styled percussion and the simple, repeating vocal line of the song title. The percussion for the release was inspired by an earlier recording by Sérgio Mendes.

The song hit #1 on the US Billboard Hot Dance Club Play chart in 1993 and made a brief appearance on the US Billboard Hot 100 chart, peaking at #71. After being re-released in late 1993, it reached #5 in the UK Singles Chart.

Hoist (device)

A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium. The load is attached to the hoist by means of a lifting hook.

Types of hoist

The basic hoist has two important characteristics to define it: Lifting medium and power type. The lifting medium is either wire rope, wrapped around a drum, or load-chain, raised by a pulley with a special profile to engage the chain. The power can be provided by different means. Common means are hydraulics, electrical and air driven motors. Both the wire rope hoist and chain hoist have been in common use since the 1800s, however mass production of an electric hoist did not start until the early 1900s and was first adapted by Germany. A hoist can be built as one integral-package unit, designed for cost-effective purchasing and moderate use, or it can be built as a built-up custom unit, designed for durability and performance. The built-up hoist will be much more expensive, but will also be easier to repair and more durable. Package units were once regarded as being designed for light to moderate usage, but since the 60s this has changed. Built-up units are designed for heavy to severe service, but over the years that market has decreased in size since the advent of the more durable packaged hoist. A machine shop or fabricating shop will use an integral-package hoist, while a Steel Mill or NASA would use a built-up unit to meet durability, performance, and repairability requirements. NASA has also seen a change in the use of package hoists. The NASA Astronaut training pool, for example, utilizes cranes with packaged hoists.

United States

Coordinates: 40°N 100°W / 40°N 100°W / 40; -100

The United States of America (USA), commonly referred to as the United States (U.S.) or America, is a federal republic composed of 50 states, a federal district, five major territories and various possessions. The 48 contiguous states and Washington, D.C., are in central North America between Canada and Mexico. The state of Alaska is in the northwestern part of North America and the state of Hawaii is an archipelago in the mid-Pacific. The territories are scattered about the Pacific Ocean and the Caribbean Sea. At 3.8 million square miles (9.842 million km²) and with over 320 million people, the country is the world's third or fourth-largest by total area and the third most populous. It is one of the world's most ethnically diverse and multicultural nations, the product of large-scale immigration from many countries. The geography and climate of the United States are also extremely diverse, and the country is home to a wide variety of wildlife.