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While Austria tapped into its natural gas stocks amid the recent stoppage of Russian gas supplies, engineers in the Austrian town of Guessing were busy producing an alternative: natural gas from wood. With the help of Swiss and Austrian scientists, the European Centre for Renewable Energy Guessing produced so-called synthetic natural gas for the first time outside a laboratory in December

One big advantage of this process is that this method can extract synthetic natural gas from renewable natural resources, said Christian Keglovits, the spokesperson of the centre that is located in a rural area in eastern Austria, some 10 kilometres from the Hungarian border

The process of turning trees into gas is done in two stages. First, wood chips are made into gas at a temperature of 900 degrees. In a second step, this gas is converted into methane that can be used to heat homes or fuel cars

Currently, the pilot facility in Guessing can turn 360 kilograms of wood into 120 cubic metres of gas within an hour - the energy equivalent of 120 litres of heating oil or 1,200 kilowatt hours. As the town does not have a gas heating system, the product is used for cars that run on natural gas

The Austrian 1-megawatt plant is too small to turn a profit, said Alfred Waser at the Paul Scherrer Institute in Villigen, Switzerland, which developed the technology together with scientists at the Vienna University of Technology

There is already interest from Sweden and Germany for larger facilities up to a capacity of 100 megawatts. "We assume that we enter an economically interesting range starting from 10 megawatts," Waser said

But the gas plants should not be too big, either. Scientists and engineers involved in the project want to avoid building plants that would be so big that they would cause more traffic from trucks bringing in wood from further away

In Guessing, the energy centre takes care to use only old or sick trees from the surrounding forests for its gas production, and not wood that is grown for other purposes

Synthetic gas is unlikely to become a full alternative to supplies from Russia and elsewhere, experts in Austria and Switzerland said. In Switzerland, around 10 per cent the country's primary energy could be produced with man-made gas if all available biomass such as animal waste, surplus wood or grass cuttings were used, Waser said

But Keglovits said the technology would help to make his small community of 3,800 less dependent of foreign suppliers. "It will make us independent from Russian natural gas to some extent, because we can draw on our local resources," he said

The gas crisis might also help the European Centre for Renewable Energy Guessing win additional research grants, Keglovits said. The funds might also help one of the centre's other (projects: turning wood into liquid fuel for cars. dpa)

موضوع مطالب:خبرها - مقالات و مطالب به زبان انگلیسی

Click on the links below or scroll down for pictures and descriptions of typical wood-destroying organisms

Subterrean Termites Dampwood Termites Drywood Termites Anobiid Beetles Wood Decay Fungus Carpenter Ants

Subterranean Termites

This species is restricted to the West, ranging from British Columbia to Mexico. These insects are swarmers. They are about 3/8" long including wings. Bodies are dark brown to almost black. Fontanelle (frontal gland pore) is present and they have front wings with two dark, hardened veins in the front portion. The wings are brownish gray with a few barely visible hairs. Their front wing scale is distinctly larger than the hind wing scale. Legs have a slightly darkened tibia and a pale tarsus.

Dampwood Termites

As their name implies, dampwood termites locate their colonies in damp, sometimes decaying wood. Representatives of three termite families (Kalotermitidae, Rhinotermitidae, Termopsidae) are included in this distinct habitat group. These termites vary in appearance from family to family. Almost all are larger than the eastern/western, desert subterranean termites with the nymphs being up to 3/4" (20 mm) long and the swarmers up to 1" (25 mm) long, including wings. They occur in the Pacific Coastal and adjacent states, the desert or semi-arid Southwest, and Southern Florida.

Drywood Termites

These insects live in wood which has a relatively low moisture content (12% or less), in the Western United States, Northwestern Mexico, and Florida. They are swarmers 7/16" to 1/2 " long including wings. Their heads and pronotums are orange brown, abdomens are dark brown, and wing membranes and hardened veins are blackened. They have Antenna with 10-11 segments. They are not hairy, their tibia exhibit no spines along their length and they have no pad between their claws.

Carpenter Ants

Several species of carpenter ants, Camponotus spp., are capable of damaging wood in buildings and other structures. Carpenter ants cause problems mainly in mountainous areas and in forested rural areas along the central and northern coastlines of California; they may also invade buildings in urban locations.

Anobiid Beetles

Anobiids Beetles are the most commonly encountered of the powderpost beetles. They are also called Deathwatch beetles because of a tapping sound they make when mating. Heard in the quiet of the night by people sitting with an ill person, this tapping was believed to indicate that death was near. Adults are from 1/32 to 3/8" long. Their shape is variable but usually elongated and cylindrical. Their color is reddish brown to black, sometimes with lighter areas of pale hairs. Prothorax hoodlike enclosing head. Antennae are not symmetrical, last three segments lengthened and expanded. Larvae are white and C-shaped. Signs of infestation are round holes in wood with piles of powdery waste below.

Wood Decay Fungus

Wood Decay fungus (poria incrassata) For a great discussion of this problem, we recommend the following web site. More information on poria incrassata

منبع:  northwesttermite

موضوع مطالب:  آناتومی و حفاظت چوب - مقالات و مطالب به زبان انگلیسی

Scientists have found life in an ecosystem trapped underneath a glacier in Antarctica for nearly 2 million years. The microbes, they suggest, are surviving the dark, oxygen-free waters by drawing energy from sulfur and iron. The findings provide insight into how life may have survived "Snowball Earth"--periods when some scientists speculate that the planet was entombed in ice--and hint at the possibility of life in other inhospitable environments, such as Mars and Jupiter's icy moon Europa

Researchers have found microbial life surviving in the most unusual places: the depths of cold and dark oceans, seething geothermal vents, and the deepest layers of permafrost. And ever since scientists discovered Antarctica's dark and mysterious subglacial lakes in the late 1960s and early 1970s, they've wondered if microbes could make a life for themselves there too. But the challenges of drilling through kilometers of ice and concerns about contaminating these pristine lakes have curtailed previous efforts to find out.

Blood Falls, a small, saltwater outflow from Taylor Glacier's subglacial lake in Antarctica's Dry Valleys, offers an alternative. The lake sits beneath 400 meters of ice and trickles out at the glacier's end, painting an orange stain across the ice as its iron-rich waters rust upon contact with air. The subglacial lake was originally part of a marine fjord system that became trapped as Taylor Glacier enclosed it between 1.5 million and 2 million years ago. Its sporadic outflow allows researchers to explore the lake without drilling or risking contamination of the isolated environment.

Geomicrobiologist Jill Mikucki, now at Dartmouth College, collected water samples from Blood Falls over 6 years. A battery of tests revealed that its waters contained almost no oxygen and hosted a community of at least 17 different types of microorganisms. But how could they have survived for so long, with no light or oxygen? Mikucki and her team uncovered three main clues. First, a genetic analysis of the microbes showed that they were closely related to other microorganisms that use sulfate instead of oxygen for respiration. Second, isotopic analysis of sulfate's oxygen molecules revealed that the microbes were modifying sulfate in some form but not using it directly for respiration. Third, the water was enriched with soluble ferrous iron, which would happen only if the organisms had converted ferric iron, which is insoluble, to the soluble ferrous form. The best explanation, the team reports in tomorrow's issue of Science, is that the organisms use sulfate as a catalyst to "breathe" with ferric iron and metabolize the limited amounts of organic matter trapped with them years ago. Lab experiments have suggested this might be possible, but it has never been observed in a natural environment.

"I think this is a fantastic study," says Alan Kaufman, a biogeochemist at the University of Maryland, College Park. It presents "a spectacular new environment that we can explore to understand life on the edge," he says. "A place like this ... would be probably as close of an analog as we can find on this planet for subpermafrost life habitats on Mars," says glaciologist Slawek Tulaczyk of the University of California, Santa Cruz. Ultraviolet radiation and other  hazards would most likely lock life away beneath the surface of the Red Planet, he notes.

By Jackie Grom
ScienceNOW Daily News
16 April 2009

موضوع مطالب:  مقالات و مطالب به زبان انگلیسی- خبرها

True Green

Wood is the original green building material. Consider the following

Green for life - In a cradle-to-grave analysis of identically constructed wood, steel and concrete homes, the wood home was more environmentally beneficial in terms of energy consumed, air/water pollution, waste production and global warming potential.*
Demand keeps it growing - Forest growth in the U.S. has continually exceeded harvest since the 1940s. We now grow 27 percent more timber each year than is harvested.
More product, less energy - Compare the energy requirements for manufacturing one ton of wood to one ton of other building materials; it takes 5 times more energy to produce cement and 24 times more energy to produce steel.
Nature's air purifier - A 2,400 sq. ft. house locks up 28.5 tons of CO₂ - roughly 7 years of emissions from a small car.

Arm yourself with the facts. Download Wood: Sustainable Building Solutions or visit our Environmental Facts & Green Building page

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