Monday, April 30, 2007

Wood

Wood is the xylem tissue of woody plants, particularly trees but also shrubs. Wood from the latter is only formed in small sizes, reducing the diversity of uses. Wood is a hygroscopic, cellular and anisotropic material. Dry wood is composed of fibers of cellulose (40%–50%) and hemicellulose (20%–30%) held together by lignin (25%–30%).
Artists can use wood to create delicate sculptures.Wood has been used by man for millenia for many purposes, being many things to many people. One of its primary uses is as fuel. It may also be used as a material, for making artworks, boats, buildings, furniture, ships, tools, weapons, etc. Wood has been an important construction material since humans began building shelters, and remains in plentiful use today. Construction wood is usually known as timber in International English, and lumber in American English. Wood may be broken down and be made into chipboard, engineered wood, hardboard, medium-density fibreboard, oriented strand board, paper or used to make other synthetic substances.

Tuesday, April 24, 2007

White oak

The White oak is one of the most wonderful of oaks. Normally not a tall tree, typically 30m tall at maturity, it nonetheless becomes quite massive and has been known to live over five hundred years. Some very large specimens can be found, the tallest recognized being 44m tall. This species lends its name to one of the principal groups of oaks, the white oaks, Quercus subgenus Quercus section Quercus; see the list of Quercus species for the other groups.

Its wood is the best and most precious of the white oaks, although wood of most of the other white oaks may be marketed with it.
The White oak is fairly tolerant of a variety of habitats, and may be found on ridges, in valleys, and in between, and in dry and moist habitats, and in moderately acid and alkaline soils. The leaves are whole and variously lobed. Sometimes the lobes are shallow, extending less than half-way to the midrib, but sometimes they are intensely lobed, with the lobes somewhat branching. The bark is a light ash-gray and somewhat peeling, variously from the top, bottom and/or sides.

White oak foliageThe acorns are long and thin relation to most oaks, and are a valuable wildlife food. Acorns of White oak were used by Native Americans as a food; they are much less bitter than the acorns of red oaks. They also are a favorite food of turkeys, wood ducks, pheasants, grackles, jays, nuthatches, thrushes, woodpeckers, rabbits, squirrels and deer.The White oak makes an exceptional shade tree, with an extremely wide spread and almost never dropping limbs. However, it does not tolerate urban conditions well, although it may thrive in residential neighborhoods.

Wednesday, April 18, 2007

Lightning

Lightning is an influential natural electrostatic release produced during a thunderstorm. Lightning's abrupt electric release is accompanied by the emission of visible light and other forms of electromagnetic radiation. The electric current passing through the release channels quickly heats and expands the air into plasma, producing acoustic shock waves in the atmosphere.

Early lightning investigate
During early investigations into electricity via Leyden jars and other instruments, a number of people planned that small scale sparks shared some similarity with lightning.

Benjamin Franklin, who also imaginary the lightning rod, endeavored to test this theory by using a spire which was being erected in Philadelphia. Whilst he was waiting for the spire completion some others conducted at Marly in France, what became to be known as the Philadelphia experiments that Franklin had optional in his book?

Franklin typically gets the credit for being the first to perform this research. The Franklin myth goes like this:

Whilst coming up for completion of the spire, he got the idea of using a flying object, such as a kite in its place. During the next shower, in June 1752, he raised a kite, accompanied by his son as an assistant. On his end of the string he emotionally involved a key and tied it to a post with a silk thread. As time passed Franklin noticed the loose fibers on the string stretching out; he then brought his hand close enough to the key and a flash jumped the gap. The rain which had fallen during the storm had covered with water the line and made it conductive.

However, in his memoirs, Franklin obviously states that he only performed this research after those made in France.

As news of the research and its specifics spread, it was met with attempts at duplication. Experiments involving lightning are always risky and commonly fatal. The most well known death during the rash of Franklin-imitators was Professor George Richman, of Saint Petersburg, Russia. He had shaped a setup similar to Franklin's, and was attending a meeting of the Academy of Sciences, when he heard thunder. He ran home with his engraver to capture the event for posterity. While the research was underway, a large ball lightning showed up, collided with Richman's head, and killed him, leaving a red spot. His shoes were blown open, parts of his clothes singed, the engraver knocked out, the doorframe of the room was split, and the door itself ragged off its hinges.

Tuesday, April 10, 2007

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.

Friday, April 06, 2007

Recording studio

A recording studio is a ability for sound recording.Recording studios normally consist of at least two rooms: the studio itself, where the sound for the recording is created, and the control room, where the sound from the studio is recorded and manipulated. Recording studios are carefully designed so that they have good acoustics and that there is good isolation between the rooms.
Equipment found in a recording studio usually includes:Reference monitors, which are loudspeakers with a flat frequency response And may also include:
Digital Audio Workstation
Music workstation
Outboard Effects, such as compressors, reverbs, or equalizers

Monday, April 02, 2007

Banksia

Banksia is a genus of around 80 species in the plant family Proteaceae. They are native to Australia, happening in all but the most arid areas. Easily recognised by their characteristic flower spikes and fruiting "cones", Banksia are a well-known Australian wildflower and a popular garden plant. They grow in forms changeable from prostrate woody shrubs to trees up to 25 metres tall. They are generally known as Banksias or Australian Honeysuckle Trees.
Banksias grow as trees or woody shrubs. The largest trees, the Coast Banksia, B. integrifolia, and the River Banksia, B. seminuda, often grow over 15 metres tall, and may be up to 25 metres tall. Banksia species that grow as shrubs are typically erect, but there are several species that are prostrate, with branches that grow on or below the soil.