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August 31, 2006, 5:39 AM CT

A New Water Test

A New Water Test
Water is essential for life. Nevertheless, even small amounts of water in the wrong places such as fuels, lubricants, or organic solvents can cause motors to sputter, metal parts to rust, or chemical reactions to go awry. That's why one of the most common lab tests performed in industry is one that looks for traces of water in other substances, even though the test itself is complicated and time-consuming.

A new method for detection and measurement of small amounts of water, developed in the lab of Dr. Milko van der Boom in the Weizmann Institute's Organic Chemistry Department, might allow such tests to be performed accurately and quickly. Van der Boom and postdoctoral fellow Dr. Tarkeshwar Gupta created a versatile film on glass that is only 1.7 nanometers thick. The film can measure the number of water molecules in a substance even when it contains only a few parts per million.

"The problem," says van der Boom, "is that water is hard to detect and to quantify." His method is a departure from prior sensing techniques. In general, such sensor systems are based on relatively weak but selective "host-guest" interactions. In the Weizmann Institute team's sensor, metal complexes embedded in the film steal electrons from the water molecules. When the number of electrons in the metal complexes changes, so does their color, and this change can be read optically. Devices based on optical readout do not need to be wired directly to larger-scale electronics an issue that's still a tremendous challenge for much of molecular-based electronics.........

Posted by: John      Permalink         Source


August 29, 2006, 6:35 PM CT

Acer e310 GPS

Acer e310 GPS
Acer showed off its new e310 GPS system today at the IFA 2006 Germany. The e310 is a portable handheld GPS device that runs on the Microsoft Windows CE. NET 5,0 software and boasts a 2.8-inch large 320 x 240 QVGA Touchscreen display with insight angle. The GPS is powered by a Samsung S3C2442XL processor that runs at a clock speed of 300MHz and also incorporates an integrated SiRF star iii LP government inspection department antenna.

Measuring 5.8 x 10.3 x 1.8 cm, it is absolutely hassle free to carry around and fits your palm with ease, as it is just about the size of cigarette box or may be a touch bigger. It includes a 64MB RAM 64MB of flash ROM. It houses special keys like navigation menu key, two volume keys, and the RESET key. If that's not all, it includes an MP3 player and a photo viewer as well. on the connectivity side, it comes with a USB2.0 and autoloading cable. The GPS can deliver upto 4 hours running time with navigation and a staggering 8 hours when in normal use.........

Posted by: John      Permalink         Source


August 29, 2006, 5:58 PM CT

Sparganium Erectum

Sparganium Erectum
Thanks again to marcella2@Flickr for sharing a photograph (original image | BPotD Flickr Group Pool). The last time a photograph from marcella2@Flickr was featured on BPotD, over three dozen images of plants were available by clicking on the marcella2@Flickr link - now there's over five dozen, so you might like to revisit them.

I should first of all note that I've changed the name of the plant posted by marcella2 from Sparganium ramosum to the catch-all Sparganium erectum (a number of Sparganium are listed as being synonymous to Sparganium erectum). I'm following the nomenclature suggested by Missouri Botanical Garden's TROPICOS database, but with reservation. In a conversation with Richard Lansdown ten days ago or so, Richard expressed the opinion that many of the less-examined plants sharing the same name in both Europe and North America are actually quite different from one another. Even the Flora of North America expresses reservation about the nomenclature within this genus, because the last work done on it (in the mid 1980s) did not contain detailed studies of the species across their complete ranges. A grain of salt is required, it seems.

I've an inexplicable soft spot for plants in the genus Sparganium, despite the fact that some have been declared a noxious weed. It may be that the soft spot stems from the exotic appearance - exotic, at least, to someone first learning plants through observing the native plants of Manitoba. I still find them interesting, and I know if I encountered some similar to these, I'd spent quite a bit of time photographing them.........

Posted by: Edwin      Permalink         Source


August 29, 2006, 5:15 AM CT

Acoustic data may reveal hidden oil supplies

Acoustic data may reveal hidden oil supplies
Just as doctors use ultrasound to image internal organs and unborn babies, MIT Earth Resources Laboratory scientists listen to the echoing language of rocks to map what's going on tens of thousands of feet below the Earth's surface.

With the help of a new $580,000 US Department of Energy (DOE) grant, the earth researchers will use their skills at interpreting underground sound to seek out "sweet spots"--pockets of natural gas and oil contained in fractured porous rocks--in a Wyoming oil field. If the method proves effective at determining where to drill wells, it could eventually be used at oil and gas fields across the country.

A major domestic source of natural gas is low-permeability or "tight" gas formations. Oil and gas come from organic materials that have been cooked for eons under the pressure and high heat of the Earth's crust. Some underground reservoirs contain large volumes of oil and gas that flow easily through permeable rocks, but sometimes the fluids are trapped in rocks with small, difficult-to-access pores, forming separate scattered pockets. Until recently, there was no technology available to get at tight gas.

Tight gas is now the largest of three unconventional gas resources, which also include coal beds and shale. Production of unconventional gas in the United States represented around 40 percent of the nation's total gas output in 2004, as per the DOE, but could grow to 50 percent by 2030 if advanced technologies are developed and implemented.........

Posted by: John      Permalink         Source


August 29, 2006, 4:44 AM CT

Fuel Cells To Power Unmanned Aerial Vehicle

Fuel Cells To Power Unmanned Aerial Vehicle Thomas Bradley and Reid Thomas go through the procedure of starting up the fuel cell aircraft
Georgia Institute of Technology scientists have conducted successful test flights of a hydrogen-powered unmanned aircraft thought to bethe largest to fly on a proton exchange membrane (PEM) fuel cell using compressed hydrogen.

The fuel-cell system that powers the 22-foot wingspan aircraft generates only 500 watts. "That raises a lot of eyebrows," said Adam Broughton, a research engineer who is working on the project in Georgia Tech's Aerospace Systems Design Laboratory (ASDL). "Five hundred watts is plenty of power for a light bulb, but not for the propulsion system of an aircraft this size." In fact, 500 watts represents about 1/100th the power of a hybrid car like a Toyota Prius.

A collaboration between ASDL and the Georgia Tech Research Institute (GTRI), the project was spearheaded by David Parekh, GTRI's deputy director and founder of Georgia Tech's Center for Innovative Fuel Cell and Battery Technologies.

Parekh wanted to develop a vehicle that would both advance fuel cell technology and galvanize industry interest. While the automotive industry has made strides with fuel cells, apart from spacecraft, little has been done to leverage fuel cell technology for aerospace applications, he noted.

"A fuel cell aircraft is more compelling than just a lab demonstration or even a fuel cell system powering a house," Parekh explained. "It's also more demanding. With an airplane, you really push the limits for durability, robustness, power density and efficiency."........

Posted by: John      Permalink         Source


August 28, 2006, 9:08 PM CT

Nanocantilevers Yield Surprises

Nanocantilevers Yield Surprises
Scientists at Purdue University have made a discovery about the behavior of tiny structures called nanocantilevers that could be crucial in designing a new class of ultra-small sensors for detecting viruses, bacteria and other pathogens.

The nanocantilevers, which resemble tiny diving boards made of silicon, could be used in future detectors because they vibrate at different frequencies when contaminants stick to them, revealing the presence of dangerous substances. Because of the nanocantilever's minute size, it is more sensitive than larger devices, promising the development of advanced sensors that detect minute quantities of a contaminant to provide an early warning that a dangerous pathogen is present.

The scientists were surprised to learn that the cantilevers, coated with antibodies to detect certain viruses, attract different densities - or quantity of antibodies per area - depending on the size of the cantilever. The devices are immersed into a liquid containing the antibodies to allow the proteins to stick to the cantilever surface.

"But instead of simply attracting more antibodies because they are longer, the longer cantilevers also contained a greater density of antibodies, which was very unexpected," said Rashid Bashir, a researcher at the Birck Nanotechnology Center and a professor of electrical and computer engineering and biomedical engineering at Purdue University. The research also shows that the density is greater toward the free end of the cantilevers.........

Posted by: John      Permalink         Source


August 27, 2006, 9:18 PM CT

Low Altitude Flying With Coarse Maps

Low Altitude Flying With Coarse Maps This image provides views of Earth from the Moon on 2 September
What exactly determines the time of the SMART-1 impact? What causes the uncertainty in the impact time?

The SMART-1 spacecraft is currently expected to impact the Moon's surface on 3 September 2006, at 07:41 CEST (05:41 UT). However, it is also possible that the small satellite hits the Moon on the previous orbit at 02:37 CEST (00:37 UT). Why?

The time of impact has been determined by orbit predictions following the major thruster manoeuvres performed from 23 June to 2 July 2006 (plus a few trajectory correction manoeuvres performed on 27 and 28 July 2006) - aimed at changing the impact site from the lunar far-side to the lunar near-side, taking into account the Sun-Earth-Moon gravity perturbations. These make the SMART-1 orbit perilune (point of closest approach to the lunar surface) naturally drift down about one kilometre per orbit.

In determining the impact orbit, ESA's spacecraft control experts are also taking into account the tiny perturbations to the trajectory induced by the small hydrazine thrusters to offload the spacecraft reaction wheels, and some slight additional gravity perturbations. An additional slot is also available for a corrective manoeuvre on 1 and 2 September 2006 if needed, to maintain the impact time as planned and allow ground based observations.........

Posted by: Edwin      Permalink         Source


August 27, 2006, 9:01 PM CT

Turning Fuel Ethanol Into Beverage Alcohol

Turning Fuel Ethanol Into Beverage Alcohol
Fuel ethanol could be cheaply and quickly converted into the purer, cleaner alcohol that goes into alcoholic drinks, cough medicines, mouth washes and other products requiring food-grade alcohol, say Iowa State University researchers.

But there's still a lot of purifying and studying to be done before fuel made from corn is turned into your next vodka or mixed into your morning mouth wash.

Jacek Koziel, an Iowa State assistant professor of agricultural and biosystems engineering, is leading a research project that's attempting to develop and refine two technologies that work together to efficiently purify and remove bad-tasting components from fuel ethanol. The project is partially supported by a $79,900 grant from the state's Grow Iowa Values Fund.

Koziel is collaborating on the project with Hans van Leeuwen, the vice president of MellO3z, a Cedar Rapids company that has developed technology for purifying alcoholic beverages. Van Leeuwen is also an Iowa State professor of civil, construction and environmental engineering.

Iowa certainly has an abundance of fuel ethanol for the scientists to work with. Iowa is the country's leading producer of fuel ethanol. The Iowa Corn Promotion Board says the state has 25 plants capable of producing 1.5 billion gallons per year with more plants on the way.........

Posted by: John      Permalink         Source


August 25, 2006, 4:44 AM CT

Why Earth's Aurorae Shine

Why Earth's Aurorae Shine Aurorae over Canada
ESA's Cluster mission has established that high-speed flows of electrified gas, known as bursty bulk flows, in the Earth's magnetic field are the carriers of decisive amounts of mass, energy and magnetic perturbation towards the Earth during magnetic substorms. When substorms occur, energetic particles strike our atmosphere, causing aurorae to shine.

Such colourful aurorae regularly light the higher latitudes in the northern and southern hemisphere. They are caused mostly by energetic electrons spiralling down the Earth's magnetic field lines and colliding with atmospheric atoms at about 100 kilometres altitude. These electrons come from the magnetotail, a region of space on the night-side of Earth where the Sun's wind of particles pushes the Earth's magnetic field into a long tail.

At the tail's centre is a denser region known as the plasmasheet. Violent changes of the plasmasheet are known as magnetic substorms. They last up to a couple of hours and somehow hurl electrons and other charged particles earthwards. Apart from the beautiful light show, substorms also excite the Earth's ionosphere, perturbing the reception of GPS signals and communications between the Earth and orbiting satellites.

A key issue about substorms has been to determine how they fling material earthwards. The so called 'Bursty Bulk Flows' (BBFs), flows of gas that travel at over 300 kilometres per second through the plasmasheet, were discovered in the 1980s and became a candidate mechanism.........

Posted by: Edwin      Permalink         Source


August 24, 2006, 9:49 PM CT

Microscopic passengers to hitch ride

Microscopic passengers to hitch ride
When space shuttle Atlantis rockets into space later this week, it will take along three kinds of microbes so researchers can study how their genetic responses and their ability to cause disease change.

The 'Microbe' experiment, part of the STS-115 space shuttle mission scheduled for launch Aug. 27, will study three common microorganisms -- Salmonella typhimurium, Pseudomonas aeruginosa and Candida albicans -- that have been identified as potential threats to crew health. Sending these microbes into space will allow researchers to investigate the microbes' genetic adaptation and ability to cause infectious disease in microgravity, and to better understand the astronauts' space environment. The results of this experiment will help NASA researchers evaluate the risks to astronauts on future exploration missions planned to go to the moon and Mars.

"Spaceflight holds tremendous potential for the development of novel therapeutics, vaccines and diagnostics to treat, prevent and control infectious diseases," said Cheryl A. Nickerson, Ph.D., the experiment's principal investigator and a researcher at the Biodesign Institute at Arizona State University, Tempe. "Our Microbe experiment will be the first to investigate the effects of spaceflight on the disease-causing potential and gene expression profiles of disease-causing microbes." NASA Ames Research Center, Moffett Field, Calif., developed the Microbe payload for flight.........

Posted by: Edwin      Permalink         Source


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