Wood is the xylem tissue of woody plants, especially 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 make delicate sculptures.Wood has been used by man for millenia for lots of purposes, being many things to many people. One of its main uses is as fuel. It might 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 normally known as timber in International English, and lumber in American English. Wood can 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.
Thursday, March 29, 2007
Monday, March 26, 2007
Banksia
Banksia is a genus of around 80 species in the plant family Proteaceae. They are native to Australia, occurring in all but the most arid areas. Easily recognized by their characteristic flower spikes and fruiting "cones", Banksia are a well-known Australian wildflower and a popular garden plant. They grow in forms varying from prostrate woody shrubs to trees up to 25 metres tall. They are normally 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 some species that are prostrate, with branches that grow on or below the soil.
The leaves of Banksia vary greatly among species. Sizes vary from the narrow, 1–1½ centimetre long leaves of the Heath-leaved Banksia, B. ericifolia, to the very large leaves of the Bull Banksia, B. grandis, which may be up to 45 centimetres long. The leaves of most species have serrated edges, but a few, such as B. integrifolia, do not. Leaves are usually arranged along the branches in irregular spirals, but in some species they are crowded together in whorls.
Banksias are most without difficulty recognised by their characteristic flower spike, and the woody fruiting structures that appear after flowering. The flower spike consists of a central woody axis with a furry coating; it is usually held erect, but hangs down in a few species. This axis is enclosed in tightly-packed pairs of flowers, which are attached to the axis at right angles. A single flower spike may have over a thousand flowers.
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 some species that are prostrate, with branches that grow on or below the soil.
The leaves of Banksia vary greatly among species. Sizes vary from the narrow, 1–1½ centimetre long leaves of the Heath-leaved Banksia, B. ericifolia, to the very large leaves of the Bull Banksia, B. grandis, which may be up to 45 centimetres long. The leaves of most species have serrated edges, but a few, such as B. integrifolia, do not. Leaves are usually arranged along the branches in irregular spirals, but in some species they are crowded together in whorls.
Banksias are most without difficulty recognised by their characteristic flower spike, and the woody fruiting structures that appear after flowering. The flower spike consists of a central woody axis with a furry coating; it is usually held erect, but hangs down in a few species. This axis is enclosed in tightly-packed pairs of flowers, which are attached to the axis at right angles. A single flower spike may have over a thousand flowers.
Wednesday, March 21, 2007
Nectarines
Nectarine tree in full flower The nectarine is a variation of peach that has a fuzzless skin. Though grocers treat fuzzy peaches and nectarines as dissimilar fruits, they belong to the same species. Nectarines have arisen many times from fuzzy peaches, often as bud sports. Nectarines can be white, yellow, clingstone, or freestone. Regular peach trees infrequently produce a few nectarines, and vice versa. Nectarines are more simply damaged than fuzzy peaches. The history of the nectarine is unclear; the first recorded mention is from 1616 in England, but they had probably been grown very much earlier in central Asia.
Friday, March 16, 2007
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.
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.
Sunday, March 11, 2007
Kullu
Kullu is the capital town of the Kullu district, in the state of Himachal Pradesh, India. It is situated on the banks of the Beas River in the Kullu Valley about ten kilometres north of the airport at Bhuntar. In the nearby Lug valley are placed the main forest contractors who have been extracting timber from the forests for the last 150 years and continue to do so today.
Kullu is the administrative capital with the offices of District Collector, the Superintendent of Police and the District courts. It is also the biggest and the most varied constituency for the lower house of the parliament.
As of 2001 India census,GRIndia Kullu had a population of 18,306. Males constitute 54% of the population and females 46%. Kullu has an average literacy rate of 81%, higher than the national average of 59.5%: male literacy is 84%, and female literacy is 77%. In Kullu, 10% of the population is under 6 years of age.
Kullu is the administrative capital with the offices of District Collector, the Superintendent of Police and the District courts. It is also the biggest and the most varied constituency for the lower house of the parliament.
As of 2001 India census,GRIndia Kullu had a population of 18,306. Males constitute 54% of the population and females 46%. Kullu has an average literacy rate of 81%, higher than the national average of 59.5%: male literacy is 84%, and female literacy is 77%. In Kullu, 10% of the population is under 6 years of age.
Tuesday, March 06, 2007
Science and technology in Japan
Japan is a foremost nation in the fields of scientific research, technology, machinery and medical research with the world's third biggest budget for research and development at US$130 billion, and over 677,000 researchers.
Some of Japan's more important technological contributions are found in the fields of electronics, machinery, industrial robotics, optics, chemicals, semiconductors and metals. Japan leads the world in robotics, possessing more than half (402,200 of 742,500) of the world's industrial robots used for manufacturing.It also produced QRIO, ASIMO, and Aibo. Japan is also home to six of the world's 15 biggest automobile manufacturers and seven of the world 20 largest semiconductor sales leaders.
Japan has also made headway into aerospace research and space exploration. The Japan Aerospace Exploration Agency (JAXA) conducts space and planetary research, aviation research, and growth of rockets and satellites. It also built the Japanese Experiment Module, which is slated to be launched and added to the International Space Station during Space Shuttle assembly flights in 2007 and 2008.
Some of Japan's more important technological contributions are found in the fields of electronics, machinery, industrial robotics, optics, chemicals, semiconductors and metals. Japan leads the world in robotics, possessing more than half (402,200 of 742,500) of the world's industrial robots used for manufacturing.It also produced QRIO, ASIMO, and Aibo. Japan is also home to six of the world's 15 biggest automobile manufacturers and seven of the world 20 largest semiconductor sales leaders.
Japan has also made headway into aerospace research and space exploration. The Japan Aerospace Exploration Agency (JAXA) conducts space and planetary research, aviation research, and growth of rockets and satellites. It also built the Japanese Experiment Module, which is slated to be launched and added to the International Space Station during Space Shuttle assembly flights in 2007 and 2008.
Thursday, March 01, 2007
Constituents of sand
The most common constituent of sand, in inland continental settings and non-tropical coastal settings, is silica (silicon dioxide, or SiO2), typically in the form of quartz, which, because of its chemical inertness and considerable hardness, is resistant to weathering. The composition of sand varies according to local rock sources and conditions. The bright white sands originate in tropical and subtropical coastal settings are ground-up limestone. Arkose is a sand or sandstone with significant feldspar content which is derived from the weathering and erosion of a (usually nearby) granite. Some locations have sands that contain magnetite, chlorite, glauconite or gypsum. Sands rich in magnetite are dark to black in color, as are sands derivative from volcanic basalts. The chlorite-glauconite bearing sands are usually 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 have garnets and other resistant minerals, with some small gemstones.
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