Monday, October 4, 2010

'DRY WATER' COULD MAKE A BIG SPLASH COMMERCIALLY

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An unusual substance known as "dry water," which resembles powdered sugar, could provide a new way to absorb and store carbon dioxide, the major greenhouse gas that contributes to global warming, scientists reported at the 240th National Meeting of the American Chemical Society.

The powder shows bright promise for a number of other uses, they said. It may, for instance, be a greener, more energy-efficient way of jump-starting the chemical reactions used to make hundreds of consumer products. Dry water also could provide a safer way to store and transport potentially harmful industrial materials.

Carter explained that the substance became known as "dry water" because it consists of 95 percent water and yet is a dry powder. Dry water was discovered in 1968 and got attention for its potential use in cosmetics. Scientists at the University of Hull, U.K. rediscovered it in 2006 in order to study its structure, and Cooper's group at the University of Liverpool has since expanded its range of potential applications. One of the most recent involves using dry water as a storage material for gases, including carbon dioxide. In laboratory-scale research, Cooper and co-workers found that dry water absorbed over three times as much carbon dioxide as ordinary, uncombined water and silica in the same space of time.

In another potential new application, the scientists also showed that dry water is a promising means to speed up catalyzed reactions between hydrogen gas and maleic acid to produce succinic acid, a feedstock or raw material widely used to make drugs, food ingredients, and other consumer products. "There's nothing else quite like it," said Ben Carter, Ph.D., researcher for study leader Professor Andrew Cooper. "Hopefully, we may see 'dry water' making waves in the future."

(Photo: Ben Carter)

American Chemical Society

NEW DRUG COULD HELP STOP THE SPREAD OF DISEASE DURING COUGH

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What if there was a drug that could completely eliminate airborne disease transmission that occurs when someone coughs? Researchers at the University of Alberta believe they have found a way to achieve this.

The idea behind this work came from Malcolm King and his research associate Gustavo Zayas, who work in the Division of Pulmonary Medicine at the U of A's Faculty of Medicine & Dentistry. King and Zayas developed a drug that, when inhaled, would reduce or eliminate the amount of droplets, called bioaerosol, coming out of the mouth when a disease-infected person coughs. These airborne particles can stay in the air for minutes and sometimes even hours.

In order to help perfect this drug King and Zayas enlisted in the expertise of PhD student Anwarul Hasan and associate professor Carlos Lange, both from the Faculty of Engineering's mechanical engineering department. It was Hasan and Lange's role to find out how the size and amount of the cough-emitted droplets are affected by the new drug.

After five years of research, using a simulated cough machine, Hasan discovered how the new drug can manipulate the properties of the lung fluid to almost completely suppress the emission of droplets, a research first. This discovery provides a clear target for the new drug in its early phases of development.

King and Zayas are moving forward to develop the drug in the form of a spray and plan to perform clinical trials in hopes that one day this drug could not only help stop the spread of a pandemic outbreak, but also protect nurses, doctors and other front-line health care professionals.

University of Alberta

SMOKING DURING PREGNANCY MAY HARM THE CHILD'S MOTOR CONTROL AND COORDINATION

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Women who smoke during pregnancy run the risk of adversely affecting their children's coordination and physical control according to a new study from Örebro University, Sweden, published in the Journal of Epidemiology and Community Health.

Moreover, we discovered that boys' abilities may be affected to a greater extent than those of girls, says Professor Scott Montgomery at Örebro University.

There is a link between nicotine and testosterone. Nicotine can influence development of the brain and interacts with testosterone particularly during the foetal stage, and this could make boys extra susceptible to foetal nicotine exposure, says Matz Larsson, researcher in medicine and consultant physician at Örebro University Hospital.

The results are based on a study of over 13,000 children taking part in the National Child Development Study. The children, all born in Great Britain in the same week in March 1958, are followed throughout their lives. The smoking habits of the mothers during pregnancy were also recorded.

– At the age of eleven, the children were tested by a school doctor in terms of physical control and coordination. They were set the task of picking up 20 matches against time – both with their left and right hand. They had to tick up to 200 squares against time and copy a simple figure.

– The children with mothers who had smoked at least nine cigarettes a day during pregnancy had greater difficulty completing the tests – especially when using their non-dominant hand, which for most of us is the left hand.

– Our findings suggest that women who smoke during pregnancy run the risk of harming the child's motor ability. There may be several reasons behind this. The nicotine interacts with acetylcholine, which is an important neurotransmitter and messenger when the brain is developing during the foetal stage. But it might also be the case that the mother's smoking leads to a form of foetal malnutrition, says Matz Larsson.

– We believe this is an interesting study as it is based on physical tests rather than cognitive, which are dependent on, for example, elements of learning. That makes our results less sensitive to the influence of social and economic factors. Other factors linked to the mother's smoking may still have affected the result, but the difference in motor abilities remained even after a check for such factors, says Scott Montgomery.

– These findings also help us to understand why neurological function in childhood is linked with adverse health outcomes in later life such as obesity and type 2 diabetes, as these are also associated with maternal smoking during pregnancy. In addition, it is important to take note of even a slight impairment in childhood. Quite often it can be linked to a more rapid decline in motor function and health later on in life, says Scott Montgomery.

(Photo: Örebro University, Sweden)

Vetenskapsradet

SCIENTISTS USING LASERS TO COOL AND CONTROL MOLECULES

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Ever since audiences heard Goldfinger utter the famous line, “No, Mr. Bond; I expect you to die,” as a laser beam inched its way toward James Bond and threatened to cut him in half, lasers have been thought of as white-hot beams of intensely focused energy capable of burning through anything in their path.

Now a team of Yale physicists has used lasers for a completely different purpose, employing them to cool molecules down to temperatures near what’s known as absolute zero, about -460 degrees Fahrenheit. Their new method for laser cooling, described in the online edition of the journal Nature, is a significant step toward the ultimate goal of using individual molecules as information bits in quantum computing.

Currently, scientists use either individual atoms or “artificial atoms” as qubits, or quantum bits, in their efforts to develop quantum processors. But individual atoms don’t communicate as strongly with one another as is needed for qubits. On the other hand, artificial atoms—which are actually circuit-like devices made up of billions of atoms that are designed to behave like a single atom—communicate strongly with one another, but are so large they tend to pick up interference from the outside world. Molecules, however, could provide an ideal middle ground.

“It’s a kind of Goldilocks problem,” said Yale physicist David DeMille, who led the research. “Artificial atoms may prove too big and individual atoms may prove too small, but molecules made up of a few different atoms could be just right.”

In order to use molecules as qubits, physicists first have to be able to control and manipulate them—an extremely difficult feat, as molecules generally cannot be picked up or moved without disturbing their quantum properties. In addition, even at room temperature molecules have a lot of kinetic energy, which causes them to move, rotate and vibrate.

To overcome the problem, the Yale team pushed the molecules using the subtle kick delivered by a steady stream of photons, or particles of light, emitted by a laser. Using laser beams to hit the molecules from opposite directions, they were able to reduce the random velocities of the molecules. The technique is known as laser cooling because temperature is a direct measurement of the velocities in the motion of a group of molecules. Reducing the molecules’ motions to almost nothing is equivalent to driving their temperatures to virtually absolute zero.

While scientists had previously been able to cool individual atoms using lasers, the discovery by the Yale team represents the first time that lasers have just as successfully cooled molecules, which present unique challenges because of their more complex structures.

The team used the molecule strontium monofluoride in their experiments, but DeMille believes the technique will also prove successful with other molecules. Beyond quantum computing, laser cooling molecules has potential applications in chemistry, where near absolute zero temperatures could induce currently inaccessible reactions via a quantum mechanical process known as “quantum tunneling.” DeMille also hopes to use laser cooling to study particle physics, where precise measurements of molecular structure could give clues as to the possible existence of exotic, as of yet undiscovered particles.

“Laser cooling of atoms has created a true scientific revolution. It is now used in areas ranging from basic science such as Bose-Einstein condensation, all the way to devices with real-world impacts such as atomic clocks and navigation instruments,” DeMille said. “The extension of this technique to molecules promises to open an exciting new range of scientific and technological applications.”

(Photo: Yale U.)

Yale University

HUMAN-POWERED ORNITHOPTER BECOMES FIRST EVER TO ACHIEVE SUSTAINED FLIGHT

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Aviation history was made when the University of Toronto's human-powered aircraft with flapping wings became the first of its kind to fly continuously.

The "Snowbird" performed its record-breaking flight on August 2 at the Great Lakes Gliding Club in Tottenham, Ont., witnessed by the vice-president (Canada) of the Fédération Aéronautique Internationale (FAI), the world-governing body for air sports and aeronautical world records. The official record claim was filed this month, and the FAI is expected to confirm the ornithopter's world record at its meeting in October.

For centuries engineers have attempted such a feat, ever since Leonardo da Vinci sketched the first human-powered ornithopter in 1485.

But under the power and piloting of Todd Reichert, an Engineering PhD candidate at the University of Toronto Institute for Aerospace Studies (UTIAS), the wing-flapping device sustained both altitude and airspeed for 19.3 seconds, and covered a distance of 145 metres at an average speed of 25.6 kilometres per hour.

"The Snowbird represents the completion of an age-old aeronautical dream," says lead developer and project manager Reichert. "Throughout history, countless men and women have dreamt of flying like a bird under their own power, and hundreds, if not thousands have attempted to achieve it. This represents one of the last of the aviation firsts."

The Snowbird weighs just 94 lbs. and has a wing span of 32 metres (105 feet). Although its wingspan is comparable to that of a Boeing 737, the Snowbird weighs less than all of the pillows on board. Pilot Reichert lost 18 lbs. of body weight this past summer to facilitate flying the aircraft.

With sustainability in mind, Aerospace Engineering graduate students of UTIAS learned to design and build lightweight and efficient structures. The research also promoted "the use of the human body and spirit," says Reichert.

"The use of human power, when walking or cycling, is an efficient, reliable, healthy and sustainable form of transportation. Though the aircraft is not a practical method of transport, it is also meant to act as an inspiration to others to use the strength of their body and the creativity of their mind to follow their dreams."

The Snowbird development team is comprised of two University of Toronto Engineering graduate students: Reichert, and Cameron Robertson (MASc 2009) as the chief structural engineer; UTIAS Professor Emeritus James D. DeLaurier as faculty advisor; and community volunteers Robert and Carson Dueck. More than 20 students from the University of Toronto and up to 10 exchange students from Poitiers University, France, and Delft Technical University, Netherlands, also participated in the project.

"This achievement is the direct result of Todd Reichert's dedication, perseverance, and ability and adds to the already considerable legacy of Jim DeLaurier, UTIAS's great ornithopter pioneer," said Professor David Zingg, Director of UTIAS. "It also reflects well on the rigorous education Todd received at the University of Toronto. We're very proud of Todd and the entire team for this outstanding achievement in aviation history."

University of Toronto

ELECTRICITY COLLECTED FROM THE AIR COULD BECOME THE NEWEST ALTERNATIVE ENERGY SOURCE

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Imagine devices that capture electricity from the air — much like solar cells capture sunlight — and using them to light a house or recharge an electric car. Imagine using similar panels on the rooftops of buildings to prevent lightning before it forms. Strange as it may sound, scientists already are in the early stages of developing such devices, according to a report at the 240th National Meeting of the American Chemical Society.

"Our research could pave the way for turning electricity from the atmosphere into an alternative energy source for the future," said study leader Fernando Galembeck, Ph.D. His research may help explain a 200-year-old scientific riddle about how electricity is produced and discharged in the atmosphere. "Just as solar energy could free some households from paying electric bills, this promising new energy source could have a similar effect," he maintained.

Scientists once believed that water droplets in the atmosphere were electrically neutral, and remained so even after coming into contact with the electrical charges on dust particles and droplets of other liquids. But new evidence suggested that water in the atmosphere really does pick up an electrical charge. Galembeck and colleagues confirmed that idea, using laboratory experiments that simulated water's contact with dust particles in the air. They used tiny particles of silica and aluminum phosphate, both common airborne substances, showing that silica became more negatively charged in the presence of high humidity and aluminum phosphate became more positively charged. In the future, he added, it may be possible to develop collectors, similar to the solar cells that collect the sunlight to produce electricity, to capture hygroelectricity and route it to homes and businesses. Just as solar cells work best in sunny areas of the world, hygroelectrical panels would work more efficiently in areas with high humidity, such as the northeastern and southeastern United States and the humid tropics.

American Chemical Society

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