Metal
In chemistry, a metal is a ingredient that readily loses electrons to form positive ions and has metallic bonds between metal atoms. Metals form ionic bonds with non-metals. They are sometimes described as a web of positive ions surrounded by a cloud of delocalized electrons. The metals are one of the three groups of elements as eminent by their ionization and bonding properties, along with the metalloids and nonmetals. On the periodic table, a diagonal line drawn from boron separates the metals from the nonmetals. Most elements on this line are metalloids, sometimes called semi-metals; elements to the lower left are metals; elements to the upper right are nonmetals.
Monday, September 24, 2007
Monday, September 17, 2007
Pollination
Pollination is an important step in the reproduction of seed plants: the transfer of pollen grains (male gametes) to the plant carpel, the organization that contains the ovule (female gamete). The accessible part of the carpel is called a stigma in the flowers of angiosperms and a micro Pyle in gymnosperms. The study of pollination brings mutually many disciplines, such as botany, horticulture, entomology, and ecology. Pollination is significant in horticulture because most plant fruits will not develop if the ovules are not fertilized. The pollination process as communication between flower and vector was first addressed in the 18th century by Christian Konrad Sprengel.
Pollination is an important step in the reproduction of seed plants: the transfer of pollen grains (male gametes) to the plant carpel, the organization that contains the ovule (female gamete). The accessible part of the carpel is called a stigma in the flowers of angiosperms and a micro Pyle in gymnosperms. The study of pollination brings mutually many disciplines, such as botany, horticulture, entomology, and ecology. Pollination is significant in horticulture because most plant fruits will not develop if the ovules are not fertilized. The pollination process as communication between flower and vector was first addressed in the 18th century by Christian Konrad Sprengel.
Monday, September 10, 2007
Troposphere
From the Greek word "τρέπω" importance to turn or mix. The troposphere is the lowest layer of the atmosphere; it starts at the surface and extends to between 7 km (23,000 ft) at the poles and 17 km (60,000 ft) at the equator, with some distinction due to weather factors. The troposphere has a enormous deal of vertical mixing due to solar heating at the surface. This heating warms air masses, which makes them less intense so they rise. When an air mass raises the force upon it decreases so it expands, doing work against the contrasting pressure of the surrounding air. To do work is to use energy, so the temperature of the air mass decreases. As the temperature decreases, water vapor in the air mass may concentrate or solidify, releasing latent heat that further uplifts the air mass. This process determines the maximum rate of refuse of temperature with height, called the adiabatic lapse rate.
From the Greek word "τρέπω" importance to turn or mix. The troposphere is the lowest layer of the atmosphere; it starts at the surface and extends to between 7 km (23,000 ft) at the poles and 17 km (60,000 ft) at the equator, with some distinction due to weather factors. The troposphere has a enormous deal of vertical mixing due to solar heating at the surface. This heating warms air masses, which makes them less intense so they rise. When an air mass raises the force upon it decreases so it expands, doing work against the contrasting pressure of the surrounding air. To do work is to use energy, so the temperature of the air mass decreases. As the temperature decreases, water vapor in the air mass may concentrate or solidify, releasing latent heat that further uplifts the air mass. This process determines the maximum rate of refuse of temperature with height, called the adiabatic lapse rate.
Tuesday, September 04, 2007
water taxi
A water taxi or river taxi or aquatically disposed taxi is a boat used for public transportation in cities with plentiful water channels. Many cities, including New York City, Boston, Baltimore, Fort Lauderdale, Winnipeg, Vancouver, London, and Tokyo have planned water taxis that operate in a similar manner to ferries or buses. Others, like Venice, have for-hire boats like to traditional taxis. Venice also has a vaporetto or waterbus system that operates in the same way to American "water taxis" (image).
Water taxis also activate in cottage areas where some cottages are available only by water. Visitors can drive to a local marina and take a water taxi to the final purpose.
On March 6, 2004, a "Seaport Taxi," a water taxi service operated by the Living Classrooms Foundation, capsized through a storm near Baltimore's Inner Harbor; 5 passengers died in the accident.
A water taxi or river taxi or aquatically disposed taxi is a boat used for public transportation in cities with plentiful water channels. Many cities, including New York City, Boston, Baltimore, Fort Lauderdale, Winnipeg, Vancouver, London, and Tokyo have planned water taxis that operate in a similar manner to ferries or buses. Others, like Venice, have for-hire boats like to traditional taxis. Venice also has a vaporetto or waterbus system that operates in the same way to American "water taxis" (image).
Water taxis also activate in cottage areas where some cottages are available only by water. Visitors can drive to a local marina and take a water taxi to the final purpose.
On March 6, 2004, a "Seaport Taxi," a water taxi service operated by the Living Classrooms Foundation, capsized through a storm near Baltimore's Inner Harbor; 5 passengers died in the accident.
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