Friday, August 31, 2007

Life source to help develop new technologies

Figure: Microscopic image of a metallised DNA strand between to electrodes. Image taken by Monika Fischler (Ulrich Simon Group, RWTH Aachen).Revolutionary science at the University of Leicester

The blueprint of life- DNA- could be used to enhance technologies in electronics and information storage following innovative and cutting edge science at the University of Leicester.
Dr Glenn Burley has been awarded one of only 8 coveted Advanced Research Fellowships in Chemistry worth £922 K, given annually by the Engineering and Physical Sciences Research Council (EPSRC).

The highly prestigious award will allow the Leicester research to use DNA, the molecule of inheritance, to help build tiny structures for use in technology processes and medicine.

Dr Burley said: “Astonishingly, strands of DNA can be programmed to self assemble into complex arrangements.

“DNA scaffolds made in this way could be used to hold molecule size electronic devices or be used to build materials with precise configurations.

‘By altering parts of their structure from one conformation to another, DNA can even be used as a machine’ says Dr Burley. ‘It’s amazing that nature’s hard drive can be so versatile. The real challenge now is to harness the potential of DNA in nanotechnology. If we can achieve this, then it will enable us to build devices much smaller than we can be achieved with today’s technology.”

Dr Burley said DNA nanotechnology combines chemistry, biochemistry and physics: “In the near future devices will contain DNA components alongside traditional electronic components. Other benefits of this technology include reduced cost of device construction and the potential for use in the early diagnosis of genetic diseases.

“We could use the technology to devise new methods of constructing DNA chips that can be used to predict whether a person will be predisposed to a particular disease.

Dr Burley who is now setting up his laboratory in Leicester, and who has in the past worked in Germany and Australia, collaborates with research groups within Leicester (Departments of Physics/Astronomy and Biochemistry) as well as maintaining links with collaborators in Germany (Walter Schottky Institute) and Italy (University of Modena). He is based in the Department of Chemistry, University of Leicester.

He added: “I’m thrilled to have been given this award that will allow me the time and resources to develop address how we will build tomorrow’s devices that will not impact heavily on the environment.

“It is feasible that by the end of this fellowship, we could be in a position to start thinking about a start up company. So the commercialization timeframe is in the region of five years.”

EPSRC Head of Chemistry John Baird said: "EPSRC Advanced Research Fellowships are designed to allow the recipient to pursue research of the very highest quality, free from normal academic duties. The combination of funding, which supports not just the Fellow's salary but also provides funding for a research project, is a very attractive package. This year, a total of 50 awards were made, of which 8 were in Chemistry."

For more information, please contact: Dr. Burley gab13@le.ac.uk, Web: University of Leicester

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Thursday, August 30, 2007

Side-to-side shaking of nanoresonators throws off impurities

Schematic of the experimental setup. A laser striking the base of a cantilever (blue) can excite vibrations either in the plane or perpendicular to it, depending on the frequency at which the laser is pulsed. A second laser (red) measures side-to-side motion as the cantilever chops through it. Rob Ilic/Cornell NanoScale Facility

Schematic of the experimental setup. A laser striking the base of a cantilever (blue) can excite vibrations either in the plane or perpendicular to it, depending on the frequency at which the laser is pulsed. A second laser (red) measures side-to-side motion as the cantilever chops through it. Rob Ilic/Cornell NanoScale Facility
Tiny vibrating silicon resonators are of intense interest in nanotechnology circles for their potential ability to detect bacteria, viruses, DNA and other biological molecules.

Cornell researchers have demonstrated a new way to make these resonators vibrate "in the plane" -- that is, side to side -- and have shown that this can serve a vital function: shaking off extraneous stuff that isn't supposed to be detected.
Scanning electron microscope photss of polystyrene spheres distributed on an array of nanofabricated silicon cantilevers, where they adhere by electrostatic forces. Making the cantilevers vibrate violently up and down won't shake such materials off, but shaking from side to side will. Rob Ilic/Cornell NanoScale Facility
Scanning electron microscope photss of polystyrene spheres distributed on an array of nanofabricated silicon cantilevers, where they adhere by electrostatic forces. Making the cantilevers vibrate violently up and down won't shake such materials off, but shaking from side to side will. Rob Ilic/Cornell NanoScale Facility
The research is reported in the July 14 online version of the journal Nano Letters and in the August print edition.

The typical resonator is a cantilever -- a narrow strip of silicon a few millionths of a meter long that can be made to vibrate up and down like a diving board just after someone jumps off. In research aimed at building the much-sought "lab on a chip," Professor Harold Craighead's group at Cornell and other researchers have shown that by binding antibodies to such resonators they can cause pathogens to attach to them. At the nanoscale, just adding the mass of one bacterium, virus or large molecule is enough to change the resonant frequency of vibration of the cantilever by a measurable amount, thereby signaling the presence of the pathogen.

But "If, for example, you are trying to detect E. coli, there will be more things in the fluid than E. coli, and they can weakly absorb on the detector by electrostatic forces.
This is a problem in any sort of biodetection," explained B. Rob Ilic, a researcher in the Cornell NanoScale Facility. The answer, he said, is to make the resonator vibrate from side to side. This will shake off loosely adhered materials, while whatever is tightly bound to an antibody will stay put.

Ilic and colleagues made cantilevers about a micron (millionth of a meter) wide, 5 or 10 microns long and 200 nanometers (billionths of a meter) thick, suspended over an empty space about a micron deep. When energy was pumped in from a laser or by an attached vibrating piezoelectric crystal, the cantilevers vibrated up and down at a resonant frequency that depended on their dimensions and mass.

Then the researchers demonstrated that in-plane motion can be created by hitting the base of the cantilever with a laser pulsed at the resonant frequency of the cantilever's in-plane vibration, which is different from the resonant frequency of its vibration perpendicular to the plane. To measure in-plane motion the researchers shined another laser on the free end of the cantilever and detected the chopping of the beam as the cantilever moved from side to side.

To show that in-plane motion could shake unwanted materials off of biosensors, the researchers distributed polystyrene spheres ranging from half a micron to a micron in diameter onto an array of cantilevers. The spheres, which attached themselves by electrostatic attraction, were removed by in-plane shaking. But when the cantilevers were made to vibrate more intensely up and down -- even so far that they bumped the "floor" below -- the spheres did not budge, nor did they during spinning of the entire chip.

In-plane vibration also could be used to determine how strongly particles are bound to the surface by observing how hard they need to be shaken to come loose, Ilic said. The ability to excite in-plane motion also has applications in making nanoscale gyroscopes, in nano optics and for basic physics experiments, he added. ###

Co-authors with Ilic and Craighead, who is the Charles W. Lake Jr. Professor of Engineering and professor of applied and engineering physics at Cornell, are Slava Krylov, professor in the Department of Solid Mechanics, Materials and Systems at Tel Aviv University, and Marianna Kondratovich, an undergraduate researcher in Cornell's Department of Mechanical and Aerospace Engineering.

Related Information: Craighead Research Group Contact: Press Relations Office pressoffice@cornell.edu 607-255-6074 Cornell University News Service, Bill Steele(607) 255-7164 ws21@cornell.edu

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Wednesday, August 29, 2007

Researchers Directly Deposit Gold Nanoparticles in Suspension

Horacio Espinosa, Robert R. McCormick School of Engineering and Applied Science.The delivery, manipulation and assembly of functional materials such as metal nanoparticles into predefined architectures and patterns is of great interest in nanotechnology. Nanoscale patterns of nanoparticles have the potential to be used in miniature electronic circuits or in plasmon waveguides to guide the transport of electromagnetic energy below the diffraction limit.
Nanoparticles functionalized with biological materials can also be placed between electrodes for use in biosensing applications.

Researchers from Northwestern University have now demonstrated the ability of a third-generation nanofountain probe (NFP) to directly deposit gold nanoparticles, 15 nanometers in diameter, onto silicon substrates. The research is published online by the scientific journal Langmuir.

“Such a direct-write method of deposition provides better control over resultant patterns and simplifies the process of fabricating functional structures, as compared to conventional photolithographic or microstamping techniques,” said Horacio D. Espinosa, professor of mechanical engineering in the Robert R. McCormick School of Engineering and Applied Science and co-author of the paper. Espinosa’s group pioneered the development of the nanofountain probe.

The NFP is a cantilevered probe chip that can be mounted on commercial atomic force microscopy (AFM) equipment. On-chip reservoirs hold liquid inks such as nanoparticle solutions, which are delivered through enclosed channels to ring-shaped apertured tips. High throughput microfluidic transport of molecular inks to AFM tips is of great interest since fluid is a very effective medium for the direct delivery of molecules, which self-assemble on substrates with very specific nanoscale architectures.

“The ultimate goal of this project is to develop a robust microsystem platform for the mass production of nanoscale devices, sensors and structures using chemicals, biomolecules, nanoparticles, nanotubes and nanowires,” said Espinosa.

Previous versions of the nanofountain probes were shown to be capable of depositing solutions of fluorescent dyes, alkanethiols and DNA. Among several design changes, the latest nanofountain probes have deeper microchannels to allow the facile delivery of larger particles such as gold nanoparticles 15 nanometers in diameter.

Probe-based deposition techniques are amenable to high-resolution, nanoscale and flexible patterns in which the desired structure can be easily altered at any time. Dip-pen nanolithography (DPN), in which a commercial AFM probe is coated with molecules to be deposited, is capable of making high-resolution patterns of many chemicals and biological materials. However, standard DPN techniques have not been able to deposit suspensions of solid nanoparticles.

“The nanofountain probe is not only capable of delivering such solutions but can do so continuously because the inks are contained in reservoirs on the chip,” said Andrea Ho, a co-author and graduate student in Espinosa’s group.

Because NFPs are batch-fabricated using standard micromachining processes, they can easily be mass-produced. The current NFPs produce nanoscale patterns with a linear array of 12 writing tips, but their design allows for straightforward scaling up to 2D arrays of tips. This would allow for the high-throughput, parallel deposition of nanoparticles with high resolution.

In addition to Espinosa and Ho, the Langmuir paper was authored by former post-doctoral fellow Bin Wu (lead author) and former research associate Nicolaie Moldovan.

The research was supported by the Nanoscale Science and Engineering Initiative of the National Science Foundation.

Contact: Megan Fellman fellman@northwestern.edu 847-491-3115 Northwestern University

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Tuesday, August 28, 2007

Physicist Opens New Window on Glass Puzzle

For samples, the Emory lab used mixtures of water and tiny plastic balls – each about the size of the nucleus of a cell. This model system acts like a glass when the particle concentration is increased. Photo by Eric Weeks, Emory University.When most people look at a window, they see solid panes of glass. But for decades, physicists, who view window glass at the molecular level, have pondered the question of whether or not glass is a solid or merely an extremely slow-moving liquid.
An Emory University research team led by physicist Eric Weeks has yielded another clue in the glass puzzle, demonstrating that, unlike liquids, glasses aren’t comfortable in confined spaces.

The Emory team's findings are reported in the paper "Colloidal glass transition observed in confinement," published in the Physical Review Letters July 13. The Emory research adds to the evidence that some kind of underlying structure is involved in glass transition, Weeks says. "This provides a simple framework for looking at other questions about what is really changing during the transition."

Weeks has devoted his career to probing the mysteries of "squishy" substances that cannot be pinned down as a solid or liquid. Referred to as "soft condensed materials," they include everyday substances such as toothpaste, peanut butter, shaving cream, plastic and glass.

Scientists fully understand the process of water turning to ice. As the temperature cools, the movement of the water molecules slows. At 32 F, the molecules form crystal lattices, solidifying into ice. In contrast, the molecules of glasses do not crystallize. The movement of the glass molecules slows as temperature cools, but they never lock into crystal patterns. Instead, they jumble up and gradually become glassier, or more viscous. No one understands exactly why.

"One idea for why glass gets so viscous is that there might be some hidden structure," says Weeks, associate professor of physics. "If so, one question is what size is that structure?"

The Emory Physics lab began zeroing in on this question two years ago when Hetal Patel, an undergraduate who was majoring in chemistry and history, designed a wedge-shaped chamber, using glue and glass microscope slides that allowed observation of single samples of glassy materials confined at decreasing diameters.

For samples, the Emory lab used mixtures of water and tiny plastic balls – each about the size of the nucleus of a cell. This model system acts like a glass when the particle concentration is increased.

The samples were packed into the wedge-shaped chambers, then placed in a confocal microscope, which digitally scanned cross-sections of the samples, creating up to 480 images per second. The result was three-dimensional digital movies, showing the movement and behavior of the particles over time, within different regions of the chamber.

"The ability to take microscopy movies has greatly improved during the past five to 10 years," Weeks says. "Back in the mid-90s, the raw data from one two-hour data set would be four gigabytes. It would have completely filled up your hard drive. Now, it's just a tiny part of your hard drive, like a single DVD."

The data showed that the narrower the sample chamber, the slower the particles moved and the closer they came to being glass-like. When the researchers increased the particle concentration in the samples, the confinement-induced slowing occurred at larger plate separations. The dimension between the plates at which the particles consistently slowed their movement was 20 particles across.

"It's like cars and traffic jams," Weeks says. "If you're on the highway and a few more cars get on, you don't really care because you can still move at the same speed. At 3 p.m., traffic gets worse and you may slow down a little bit. But at some point, your speed has to go from 40 mph to 5 mph. That's kind of what's happening with glass."

Previous research has shown groups of particles in dense suspensions move cooperatively. "Our work suggests glasses are solid-like because these groups can't move when the sample chamber is thinner than the typical size of these groups," Weeks says. "These experiments help us understand earlier work done with thin polymer films and other glassy materials, but as we use particles rather than atoms, we get to directly see how confinement influences the glass transition."

Nanotechnology is one example of a field that can benefit from research into the behavior of colloidal glass and plastics in tight spaces. 



"When making machines as small as a cell, people have found that they're even more fragile than you might expect," Weeks said. "One interesting thing is that small plastic structures become more fragile because, when they are really tiny, they're less glassy." ###

Emory University is one of the nation's leading private research universities and a member of the Association of American Universities. Known for its demanding academics, outstanding undergraduate college of arts and sciences, highly ranked professional schools and state-of-the-art research facilities, Emory is ranked as one of the country's top 20 national universities by U.S. News & World Report. In addition to its nine schools, the university encompasses The Carter Center, Yerkes National Primate Research Center and Emory Healthcare, the state's largest and most comprehensive health care system.

Contact: Beverly Clark beverly.clark@emory.edu 404-712-8780 Emory University

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Monday, August 27, 2007

FSU researchers developing diagnostic 'lab on a chip'

Caption: Thomas Fischer, Credit: Bill Lax/FSU Photo Lab, Usage Restrictions: None.TALLAHASSEE, Fla. -- If you have ever marveled over the orderly process by which cars, buses and other modes of transportation are directed toward their destinations in a big city,
you’ll really appreciate the work of one Florida State University chemist.

Thomas Fischer, an associate professor of chemistry and biochemistry at FSU, is designing a “smart” traffic system similar to those in major metropolises. A major difference, though, is its size: Fischer’s traffic grid is small enough to fit on a tiny microchip.

Working with an FSU postdoctoral associate, Pietro Tierno, and another colleague, Professor Tom H. Johansen of the University of Oslo in Norway, Fischer has designed a “lab on a chip” -- a small device that, when exposed to very low magnetic fields, might one day be used as a portable tool for quickly diagnosing a variety of human illnesses.

“Currently, a doctor seeking to help a sick patient may take a blood sample and send it out to a laboratory,” Fischer said. “In three or four days, the lab results will come back and the doctor will have a better idea of what ails the patient.

“With the ‘lab on a chip,’ however, it might be possible to take a single drop of the patient’s blood, place it on a small chip, and then be able to provide a very quick, inexpensive and -- most important -- accurate diagnosis.”

Fischer explained that the device would work by exposing the blood sample to very low magnetic field oscillations. In so doing, certain microscopic particles within the sample would be manipulated into “commuting” through an array of magnetic bubbles on the surface of the chip. Observing where various particles align themselves then would enable medical professionals to determine the nature of the patient’s illness.

“Single molecules marking the presence or absence of a disease will be attached to magnetic particles a billion times smaller than a marble,” Fischer said. “The magnetic traffic system then will guide these particles to different positions on the chip depending on their molecular marking.”

A paper describing the research of Fischer, Tierno and Johansen was recently published in the prestigious scientific journal Physical Review Letters. That paper, is titled “Localized and Delocalized Motion of Colloidal Particles on a Magnetic Bubble Lattice,”

In addition, Fischer, Tierno and another colleague, Lars Helseth, an assistant professor at Nanyang Technological University in Singapore, have submitted a patent application related to their ‘lab on a chip.’ The application, titled “Digital Transport of Paramagnetic Beads on Magnetic Garnet Films,” states that their goal is to “control the location and movement of molecular objects on a microchip by modulating magnetic domains on the surface of the microchip.”

A company, Siemens Medical Solutions, also has expressed interest in Fischer’s technique. Plans to develop the magnetic chip further in a joint effort are under way.

Much more basic research must be done before such a diagnostic tool is ready for the marketplace. Fischer stressed that science “often is a long, laborious process that can take years to generate results. However, this sort of research is essential if breakthroughs in medicine and the sciences are to occur.” ###

Contact: Thomas Fischer tfischer@chem.fsu.edu 850-645-3206 Florida State University, For more stories about FSU, visit our news site at fsu.com

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Sunday, August 26, 2007

Nanoparticle Technique Could Lead to Improved Semiconductors

Microscopic image of nanoparticles of the plastic semiconductor material F8BT. Courtesy: Rodrigo Palacios.AUSTIN, Texas—Devices made from plastic semiconductors, like solar cells and light-emitting diodes (LEDs), could be improved based on information gained using a new nanoparticle technique developed at The University of Texas at Austin.
As electrical charges travel through plastic semiconductors, they can be trapped much like a marble rolling on a bumpy surface becomes trapped in a deep hole. These traps of charges are known as “deep traps,” and they are not well understood.

Deep traps can be desired, as in the case of plastic semiconductors used for memory devices, but they can also decrease the efficiency of the material to conduct electrical charges. In the case of solar cells, deep traps can decrease the efficiency of the conversion of light into electricity.

To further explore the deep trap phenomenon, a group of scientists led by Professors of Chemistry and Biochemistry Paul Barbara and Allen Bard developed a single-particle technique to study small portions of semiconductor material at the nanoscale.

The scientists reported their findings in the advanced online issue of the journal Nature Materials.

“Our results strongly suggest that deep traps are formed in plastic semiconductors by a charge induced chemical reaction,” says Dr. Rodrigo Palacios, lead author and post-doctoral fellow at the Center for Nano and Molecular Science and Technology. “These traps were not there in the uncharged pristine material.”

Deep traps could be caused by defects in the semiconductor material—either native to the material or introduced impurities—with special properties that encourage charge trapping. The traps also could develop over the life of the semiconductor.

Previous techniques used to study deep traps have generally involved completed semiconductor devices, which Palacios says creates complications due to the complexity of a functional device.

For the current study, Palacios used a conjugated polymer (plastic semiconductor) material known as F8BT, which is commercially available and has promising applications in organic LEDs and solar cells.

He produced particles of F8BT with diameters about one-ten thousandth that of a human hair. He then shone light on the nanoparticles and measured changes in intensity of the resulting fluorescence. (This type of semiconductor material takes in light energy and releases part of this energy as light of a different color.)

Palacios observed deep traps forming as he electrochemically charged and discharged the semiconductor nanoparticles. The deep traps led to decreases in light emission from the material.

“With our new technique, we got detailed information on how these deep traps are formed and how long they live,” says Palacios. “In principle, this kind of information can be used to improve devices made out of these conjugated polymers, designing new materials that can avoid these deep traps or materials that might be able to form these deep traps better.”

Contacts: Dr. Rodrigo Palacios, Center for Nano and Molecular Science and Technology, 512-471-5535, rodpalacios@mail.utexas.edu; Lee Clippard, Public Affairs, 512-232-0675, news@cns.utexas.edu Web: University of Texas at Austin

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Saturday, August 25, 2007

Beyond batteries: Storing power in a sheet of paper VIDEO

Researchers turn everyday paper into resilient, rechargeable energy storage device

Troy, N.Y. – Researchers at Rensselaer Polytechnic Institute have developed a new energy storage device that easily could be mistaken for a simple sheet of black paper.
Caption: A sample of the new nanocomposite paper developed by researchers at Rensselaer Polytechnic Institute. Infused with carbon nanotubes, the paper can be used to create ultra-thin, flexible batteries and energy storage devices for next-generation electronics and implantable medical equipment. Credit: Rensselaer/Victor Pushparaj. Usage Restrictions: Please include credit line.The nanoengineered battery is lightweight, ultra thin, completely flexible, and geared toward meeting the trickiest design and energy requirements of tomorrow’s gadgets,
implantable medical equipment, and transportation vehicles.
Caption: A sample of the new nanocomposite paper developed by researchers at Rensselaer Polytechnic Institute. Infused with carbon nanotubes, the paper can be used to create ultra-thin, flexible batteries and energy storage devices for next-generation electronics and implantable medical equipment. Credit: Rensselaer/Victor Pushparaj. Usage Restrictions: Please run photo credit with image.Along with its ability to function in temperatures up to 300 degrees Fahrenheit and down to 100 below zero, the device is completely integrated and can be printed like paper.
The device is also unique in that it can function as both a high-energy battery and a high-power supercapacitor, which are generally separate components in most electrical systems. Another key feature is the capability to use human blood or sweat to help power the battery.

Details of the project are outlined in the paper “Flexible Energy Storage Devices Based on Nanocomposite Paper” published Aug. 13 in the Proceedings of the National Academy of Sciences.

The semblance to paper is no accident: more than 90 percent of the device is made up of cellulose, the same plant cells used in newsprint, loose leaf, lunch bags, and nearly every other type of paper.

Rensselaer researchers infused this paper with aligned carbon nanotubes, which give the device its black color. The nanotubes act as electrodes and allow the storage devices to conduct electricity. The device, engineered to function as both a lithium-ion battery and a supercapacitor, can provide the long, steady power output comparable to a conventional battery, as well as a supercapacitor’s quick burst of high energy.

The device can be rolled, twisted, folded, or cut into any number of shapes with no loss of mechanical integrity or efficiency. The paper batteries can also be stacked, like a ream of printer paper, to boost the total power output.

“It’s essentially a regular piece of paper, but it’s made in a very intelligent way,” said paper co-author Robert Linhardt, the Ann and John H. Broadbent Senior Constellation Professor of Biocatalysis and Metabolic Engineering at Rensselaer.

“We’re not putting pieces together – it’s a single, integrated device,” he said. “The components are molecularly attached to each other: the carbon nanotube print is embedded in the paper, and the electrolyte is soaked into the paper. The end result is a device that looks, feels, and weighs the same as paper.”

The creation of this unique nanocomposite paper drew from a diverse pool of disciplines, requiring expertise in materials science, energy storage, and chemistry. Along with Linhardt, authors of the paper include Pulickel M. Ajayan, professor of materials science and engineering, and Omkaram Nalamasu, professor of chemistry with a joint appointment in materials science and engineering. Senior research specialist Victor Pushparaj, along with postdoctoral research associates Shaijumon M. Manikoth, Ashavani Kumar, and Saravanababu Murugesan, were co-authors and lead researchers of the project. Other co-authors include research associate Lijie Ci and Rensselaer Nanotechnology Center Laboratory Manager Robert Vajtai.

The researchers used ionic liquid, essentially a liquid salt, as the battery’s electrolyte. It’s important to note that ionic liquid contains no water, which means there’s nothing in the batteries to freeze or evaporate. “This lack of water allows the paper energy storage devices to withstand extreme temperatures,” Kumar said.

Along with use in small handheld electronics, the paper batteries’ light weight could make them ideal for use in automobiles, aircraft, and even boats. The paper also could be molded into different shapes, such as a car door, which would enable important new engineering innovations.

“Plus, because of the high paper content and lack of toxic chemicals, it’s environmentally safe,” Shaijumon said.

Paper is also extremely biocompatible and these new hybrid battery/supercapcitors have potential as power supplies for devices implanted in the body. The team printed paper batteries without adding any electrolytes, and demonstrated that naturally occurring electrolytes in human sweat, blood, and urine can be used to activate the battery device.

“It’s a way to power a small device such as a pacemaker without introducing any harsh chemicals – such as the kind that are typically found in batteries – into the body,” Pushparaj said.

The materials required to create the paper batteries are inexpensive, Murugesan said, but the team has not yet developed a way to inexpensively mass produce the devices. The end goal is to print the paper using a roll-to-roll system similar to how newspapers are printed.

“When we get this technology down, we’ll basically have the ability to print batteries and print supercapacitors,” Ajayan said. “We see this as a technology that’s just right for the current energy market, as well as the electronics industry, which is always looking for smaller, lighter power sources. Our device could make its way into any number of different applications.”

The team of researchers has already filed a patent protecting the invention. They are now working on ways to boost the efficiency of the batteries and supercapacitors, and investigating different manufacturing techniques.

"Energy storage is an area that can be addressed by nanomanufacturing technologies and our truly inter-disciplinary collaborative activity that brings together advances and expertise in nanotechnology, room-temperature ionic liquids, and energy storage devices in a creative way to devise novel battery and supercapacitor devices," Nalamasu said. ###

The paper energy storage device project was supported by the New York State Office of Science, Technology, and Academic Research (NYSTAR), as well as the National Science Foundation (NSF) through the Nanoscale Science and Engineering Center at Rensselaer.

About Rensselaer: Rensselaer Polytechnic Institute, founded in 1824, is the nation’s oldest technological university. The university offers bachelor’s, master’s, and doctoral degrees in engineering, the sciences, information technology, architecture, management, and the humanities and social sciences. Institute programs serve undergraduates, graduate students, and working professionals around the world.

Rensselaer faculty are known for pre-eminence in research conducted in a wide range of fields, with particular emphasis in biotechnology, nanotechnology, information technology, and the media arts and technology. The Institute is well known for its success in the transfer of technology from the laboratory to the marketplace so that new discoveries and inventions benefit human life, protect the environment, and strengthen economic development.

Contact: Michael Mullaney mullam@rpi.edu 518-276-6161 Rensselaer Polytechnic Institute

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Hangings, Executions and other good stuff Excerpt: Iran has hanged up to 30 people in the past month amid a clampdown prompted by alleged U.S.-backed plots to topple the regime, while the EU urges Texas to end executions. Iran: (here via here) Many executions have been carried Weblog: Right Truth Tracked: 08.26.07 - 12:39 pm

When Fake News is Presented as Truth by the Main S Excerpt: Its a mystery to me as to why the Old Media insists on reporting the amateurish propaganda that comes out of the middle east while ignoring reporting any news stories that promote the best interest of the United States. Its a very strange phenomena t... Weblog: Blue Star Chronicles Tracked: 08.26.07 - 4:46 pm

Americans, Iraqis interact at historical monument Excerpt: It has been more than 10 years since any Iraqi native has been allowed to visit the Ziggurat of Ur, which is the most dominant landmark on Ali Base, because during the reign of Suddam Hussein the installation was used by the Iraqi army.Weblog: Rosemary's Thoughts Tracked: 08.26.07 - 7:13pm

Adam's Blog The Trouble With Huckabee… Mike Huckabee is a decent man, but his fiscal record dooms his ability to bring Conservatives together. Also, Howard Dean and the DNC doing something right for a change, the Deficit’s falling but a Democrat tax and spending increase could make i… 08.26.07 - 11:08pm

Adeline and Hazel Owen Wilson Hospitalized Following Possible Suicid… The National Enquirer later revealed that he had been found by a family member after he had sliced his left wrist and taken an undetermined number of pills. His condition was listed as very serious and his prognosis grim. He has sense been upgraded a….. 08.27.07 1.00am

Right Voices Hey MSM You Forgot To Report That France’s Health Care System Broken and Should Copy US!… French Expert Details Failures in System, Compares to U.S. In a nutshell, the system is not sustainable anymore. “It’s true we really have good access, but what if the system is not sustainable anymore?” says Teil. “It’s … 08.27.07 1:21pm

Leaning Straight Up Says: More cartoon “Dhimmitude”: Newspapers refuse to print Opus cartoon Mocking Islam I have avoided the use of this term in the past as it is pejorative and far too convenient for my tastes. But more and more, the ass kissing of Muslim hyper-sensitivity has been irking me, so I see no reason to continue ignoring it for what it is. August 27th, 2007 at 4:57 pm

Friday, August 24, 2007

Scientists train nano-'building blocks' to take on new shapes

Caption: Transmission electron microscopy image of one-dimensional assembled structures created by a research team from the University of Delaware and the University of Washington in St. Louis. Credit: Darrin Pochan/University of Delaware. Usage Restrictions: Image must include credit to University of Delaware.Scientists train nano-'building blocks' to take on new shapes, as reported in Science

Researchers from the University of Delaware and Washington University in St. Louis have figured out how to train synthetic polymer molecules to behave--to literally “self-assemble”
-- and form into long, multicompartment cylinders 1,000 times thinner than a human hair, with potential uses in radiology, signal communication and the delivery of therapeutic drugs in the human body.

The discovery, a fundamental new tool for nanotechnology, is reported in the Aug. 3 issue of the prestigious journal 'Science.'
Caption: Darrin Pochan, University of Delaware associate professor of materials science and engineering. Credit: Kathy F. Atkinson/University of Delaware. Usage Restrictions: Photo must include credit to University of Delaware.Darrin Pochan, associate professor of materials science and engineering at the University of Delaware, and Karen Wooley, the James S. McDonnell Distinguished Professor of Arts & Sciences at Washington University in St. Louis,
led the research effort, which also involved co-authors Honggang Cui, a recent doctoral graduate, and doctoral student Sheng Zhong at UD, and Zhiyun Chen, a doctoral advisee of Wooley's. The research was supported by a Nanoscale Interdisciplinary Research Team (NIRT) grant from the National Science Foundation.

The focus of the research was block copolymers, which are synthetic molecules that contain two or more chemically different segments bonded together. Block copolymers are used to make a variety of materials such as plastics, rubber soles for shoes, and more recently, portable memory sticks (“flash drives”) for computers.

“A block copolymer is a long-chain molecule, a length of which, or block, that is chemically different than the other,” Pochan said. “In our case, we took one block that loves water, and another part that does not. So when you put them in solution, the water-hating blocks try to get away from the water, and that's how you get different shapes, called micelles, to form.”

The system used by the scientists consisted of a tri-block copolymer composed of polyacrylic acid, polymethylacrylate, and polystyrene introduced into a solution of tetrahydrofuran and water, and organic diamines. The technique relied on divalent organic counter ions and solvent mixtures to drive the organization of the block copolymers down specific pathways into snake-like, one-dimensional structures.

Much of the research was conducted using the high-powered microscopes in the UD College of Engineering's W. M. Keck Electron Microscopy Facility, which is under the direction of Chaoying Ni. Technician Frank Kriss assisted the research team.

Wooley, who is an expert in polymer chemistry, and Pochan, who is a material scientist, met at research conferences, where they discussed their respective projects. She had been designing sphere-shaped micelles for use in drug delivery and radiology, but noticed under some solution conditions that her students could produce different shapes.

Although their labs are located some 900 miles apart, the scientists say their research has been a “great and synergistic collaboration.”

“In the world of self-assembly for nanotechnology, it's challenging to make something other than the shape of a ball,” Pochan noted. “If you put little balls full of a drug into the bloodstream, the body's organs and immune system will get rid of them in around a day. But if you place the molecules into long, floppy cylinders, they may stay in the body for weeks,” Pochan noted.

Changing the shape of the micelle could carry a drug in the human body for a long period of time, according to Pochan, potentially providing the sustained delivery of chemotherapy from a single injection.

“Moving from a sphere to a cylinder, you could conceivably deliver two or three or four different drugs in one injection, one to one part of the body and others to other parts of the body all through the same self-assembly,” he said.

Although the research is far from practical applications, the team's discovery has yielded a new, fundamental “bottom-up” technique for building nanostructures.

“It's all about constructing materials and nanostructures in an easy way,” Pochan said. “The goal is to design a molecule with all the rules--all the information it needs--to zip up into the desired shape and size that you want. Then you throw them in the water and see what you get--hopefully the desired, complex nanostructure.”

Ironically, Pochan thought he was done working with block copolymers when he was in graduate school years ago.

“I'm now building on stuff I did in grad school in the '90s on rubber and plastics,” he said. “However, if you look at block copolymers as a tool for self-assembly, there are many more potential applications than rubber for your boot or plastic coating for your floor,” he noted.

“We can use those same molecules, but train them to get something very useful as far as high technology goes,” he said. “It's funny how research comes back in style, and we find new uses for 'old tools.'” ###

Contact: Tracey Bryant tbryant@udel.edu 302-831-8185 University of Delaware
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Thursday, August 23, 2007

Nano-layer of ruthenium stabilizes magnetic sensors

Caption: A thin layer of ruthenium (green in the cartoon) improves magnetic sensors by modulating interactions between a nickel/iron film (blue) that responds to external magnetic fields and an iridium/manganese stabilizer film (pink). The ruthenium aligns its electron spins, indicated by arrows, with the nearest layers in both films. Credit: NIST. Usage Restrictions: None.A layer of ruthenium just a few atoms thick can be used to fine-tune the sensitivity and enhance the reliability of magnetic sensors, tests at the National Institute of Standards and Technology (NIST) show.*
The nonmagnetic metal acts as a buffer between active layers of sensor materials, offering a simple means of customizing field instruments such as compasses, and stabilizing the magnetization in a given direction in devices such as computer hard-disk readers.

In the NIST sensor design, ruthenium modulates interactions between a ferromagnetic film (in which electron “spins” all point in the same direction) and an antiferromagnetic film (in which different layers of electrons point in opposite directions to stabilize the device). In the presence of a magnetic field, the electron spins in the ferromagnetic film rotate, changing the sensor’s resistance and producing a voltage output. The antiferromagnetic film, which feels no force because it has no net magnetization, acts like a very stiff spring that resists the rotation and stabilizes the sensor. The ruthenium layer (see graphic) is added to weaken the spring, effectively making the device more sensitive. This makes it easier to rotate the electron spins, and still pulls them back to their original direction when the field is removed.

NIST tests showed that thicker buffers of ruthenium (up to 2 nanometers) make it easier to rotate the magnetization of the ferromagnetic film, resulting in a more sensitive device. Thinner buffers result in a device that is less sensitive but responds to a wider range of external fields. Ruthenium layers thicker than 2 nm prevent any coupling between the two active films. All buffer thicknesses from 0 to 2 nm maintain sensor magnetization (even resetting it if necessary) without a boost from an external electrical current or magnetic field. This easily prevents demagnetization and failure of a sensor.

The mass-producible test sensors, made in the NIST clean room in Boulder, Colo., consist of three basic layers of material deposited on silicon wafers: The bottom antiferromagnetic layer is 8 nm of an iridium/manganese alloy, followed by the ruthenium buffer, and topped with 25 nm of a nickel/iron alloy. The design requires no extra lithography steps for the magnetic layers and could be implemented in existing mass-production processes. By contrast, the conventional method of modulating magnetoresistive sensors—capping the ends of sensors with magnetic materials—adds fabrication steps and does not allow fine-tuning of sensitivity. The new sensor design was key to NIST’s recent development of a high-resolution forensic tape analysis system for the Federal Bureau of Investigation (see Magnetic Tape Analysis “Sees” Tampering in Detail).

* S.T. Halloran, F.C. da Silva, H.Z. Fardi and D.P. Pappas. Permanent-magnet-free stabilization and sensitivity tailoring of magneto-resistive field sensors, Journal of Applied Physics. August 1, 2007

Contact: Laura Ost laura.ost@nist.gov 303-497-4880 National Institute of Standards and Technology (NIST)

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Tuesday, August 21, 2007

IED Nanotech Research

Mizzou Engineering Professor Shubhra Gangopadhyay and her research team have been selected to receive a nanotechnology award in November. Photo courtesy of MU PublicationsMizzou nanotechnology research team wins industry award By Vicki Hodder, CoE senior information specialist

Mizzou Engineering Professor Shubhra Gangopadhyay and her research team have won an industry award for combining nanotechnology with microchip–based technology to generate powerful shock waves and energy.
Nanotech Briefs magazine, a three–year–old monthly digital publication for nanotechnology researchers, has selected the Mizzou team’s work as one of the year’s top 50 technologies or innovations in the nanotechnology field. Gangopadhyay, an electrical and computer engineering faculty member, will officially receive the “Nano 50” award during a Nov. 14–15 nanotechology conference in Boston, Mass

“This is fantastic recognition for you and for nanoscience at MU,” said Jim Coleman, MU’s vice chancellor for research.

The Gangopadhyay team’s invention of a nanotechnology process for creating shock waves that can be integrated with microchip technology has broad potential defense, commercial and medical applications.

Energy generated by the process may initiate explosions or create electrical power, Gangopadhyay said. In the medical field, the process’ shock waves may be used to increase the effectiveness of anti–cancer drugs and help deliver other medicines as well, she said.

Shubhra Gangopadhyay, LaPierre Chair and Professor. 243 Engineering Building West University of Missouri Columbia , Missouri 65211. Phone: (573) 882-4070 Fax: (573) 882-0397 Email: mailto:facultyname@missouri.edu. Website: The Gangopadhyay Research Group

Posted July 3, 2007 Copyright © 2006 — Curators of the University of Missouri DMCA and other copyright information. All rights reserved, Please send comments or questions to engineering@missouri.edu

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Rosemary's Thoughts, The Random Yak, Jeanette's Celebrity Corner, Nuke's News & Views, Stuck On Stupid, Webloggin, The Bullwinkle Blog, The Amboy Times, Conservative Cat, Conservative Thoughts, Inside the Northwest-Territory, third world county, The World According to Carl, The Pink Flamingo, Planck's Constant, Dumb Ox Daily News, The Yankee Sailor, and Gone Hollywood, thanks to Linkfest Haven Deluxe. Trackposted to Perri Nelson's Website, Rosemary's Thoughts, DeMediacratic Nation, Big Dog's Weblog, Right Truth, Leaning Straight Up, Conservative Cat, Conservative Thoughts, Faultline USA, Right Celebrity, , The World According to Carl, Pirate's Cove, The Pink Flamingo, The Yankee Sailor, and Gone Hollywood, thanks to Linkfest Haven Deluxe.

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The Petraeus Report, Part II: The Pigeon's Response Excerpt: Success in Iraq depends on a stable, strong, and secure government: three ingredients the al-Maliki administration's lacking. Weblog: Diary of the Mad Pigeon Tracked: 08.22.07 - 2:33 am

CommonSenseAmerica Says: Death Toll and Crime Rate Rises . . .
While our elected officials enjoy their August vacation, Americans are left defenseless against criminal illegal aliens.Maryland:The man alleged to be responsible for a fatal hit-and-run collision along Route 29 is in the country illegally, authoriti… August 22, 2007 at 5:53 am

Blog at MoreWhat.com » Blog Archive » On FISA: Who Invited the ACLU? Says: It seems reasonable that part of why FISA was established includes providing another layer of oversight within government on sensitive issues. August 22, 2007 at 7:22 am

Let the screaming and caterwauling begin... Excerpt: Or at least the usual fallacies, shallow dismissals, sneers and dogmatism continue. A new movie is set to premiere next year on that holy day for some ... Weblog: Mark My Words Tracked: 08.22.07 - 4:35 pm

Masked Men Set Iraqi Child on Fire Excerpt: Masked men pour gasoline on a 5-year-old Iraqi boy and set him on fire for no apparent reason. This is the kind of enemy our Soldiers are fighting in Iraq. These terrorists prey on the most vulnerable and least able to defend themselves. Weblog: Blue Star Chronicles Tracked: 08.22.07 - 5:24 pm

The world's irony meter just exploded Excerpt: I'm not sure if it was because of what Hillary! Clinton just said or due to a jihadi jackass doubling over in laughter over what she said ... Weblog: Mark My Words Tracked: 08.22.07 - 6:11 pm

Geraldo Rivera, new spokesman for criminal illegal aliens Excerpt: Today Geraldo took the leader of Mothers Against Illegal Aliens on Fox on Your World With Neil Cavuto. Geraldo also took on Tom Tancredo on Hannity and Colmes. I guess he is Fox's token 'balanced' commenter who is FOR criminal Weblog: Right Truth Tracked: 08.22.07 - 8:18 pm

Amazing Angels (and OTB) Excerpt: Just in case you have not heard, there is an organization called Soldiers' Angels. You may have noticed that I've added a link to the Project Valour IT donations. These men and women are absolutely outstanding, and these Angels', working behind the ... Weblog: Rosemary's Thoughts Tracked: 08.22.07 - 9:24 pm

Rhymes With Right Says: Zero Tolerance = Zero Sense In Arizona… As a teacher, my only reaction is scorn for those who made this absurd decision. Chandler school officials have suspended a 13-year-old boy for sketching a picture that resembled a gun, saying it posed a threat to classmates. But parents…… August 22nd, 2007 at 11:44 pm

Rhymes With Right Says: Romney Outlines Federalist Stance On Abortion… Within the GOP, there is a wide-range of positions on abortion. And while the official platform position is one supportive of a Human Life Amendment to the Constitution, there is a sizable group that simply believes that Roe v. Wade…… August 22nd, 2007 at 11:49 pm

Conservative Cat Says: Michelle Obama’s Inexperience Gets Her Hammered…
The Obama campaign has issued a clarification to the effect that Michelle Obama was not attacking Hillary Clinton when she talked about the important of "running your own house" if you hope to run the White House. It’s obvious that…… August 23rd, 2007 at 1:00 am

CommonSenseAmerica Says: Jihad: The Musical, ABC News asks, “Will it Bomb?”:‘Jihad: the Musical’ Hits Edinburgh FestivalWith songs like “I Wanna Be Like Osama” and “Building a Bomb Today” set to jaunty tunes and a high-kicking chorus line, “… August 23th, 2007 at 3:52 am

Those Notorious Greeley Girls Excerpt: Who, then, are these mysterious golden-agers? And what did they do that so infuriated the peaceful Muslim ummah and set the Middle East ablaze?They are, God bless them, the Notorious Greeley Girls. Weblog: Faultline USA Tracked: 08.23.07 - 4:50 am

Manly Men & Womanly Ladies (OTB) Excerpt: Dear Men, Speaking for myself, I was raised by a very strong Father. Regardless as to whether he was right or wrong, us children knew where we stood. One time I asked him how to the difference between right and wrong and he ... Weblog: Rosemary's Thoughts Tracked: 08.23.07 - 6:53 am

Belgian Muslims Want a Ban on Easter eggs Excerpt: Yes, Easter eggs. Add this to pork, hot cross buns, alcohol, Jewish cookies, Coca Cola and all the other food related grievences, and the menu for dhimmis is getting mighty slim.JW: If headscarves are banned for employees who work at Weblog: The Amboy Times Tracked: 08.23.07 - 8:01 pm

CommonSenseAmerica Says, Well, here’s a shocker. The Washington Times is reporting that there may be yet another reason this administration has refused to enforce our immigration laws, especially our laws that fine employers of illegal aliens. Tracked August 23rd, 2007 at 12:35 pm

The Arrogance Of Mexico Rhymes With Right Says: A Mexican Senate committee passed a measure Wednesday urging President Felipe Calderon to send a diplomatic note to the United States protesting the deportation of an illegal migrant who took refuge in a Chicago church for a year. 08.23.07 02:41 PM

Right Voices Says:What Short Memories The MSM Have….TV News and Terror in Cambodia’ The media is having a field day with Bush’s speech yesterday, in which he said Vietnam. Vietnam, that’s right. Vietnam, as in we fled and millions are now dead. The left has pounced on this with their usual obtuse efforts to miss the cle... August 24th, 2007 at 9:56 am

Levitating Nanomachines Excerpt: The total FY'08 federal budget request for nanotechnology was $1.44 billion (across all agencies). By their nature, nano items will stick together. However, physicists at the University of St. Andrews (Scotland) have discovered a way to to turn that e... Weblog: Stormwarning's Counterterrorism Tracked: 08.25.07 - 4:03 pm

Using a magnet to tune a magnet

Caption: The technical use of the magnet is determined by the ease with which the walls can be moved, or equivalently, by the force with which they are pinned. Strong pinning gives a hard magnet, soft pinning a soft magnet. The distance between the walls is 100 nanometers or 10 millionths of a centimeter. Credit: Y-A. Soh and G. Aeppli, Usage Restrictions: None. An international research team, led by scientists at the London Centre for Nanotechnology (LCN), has found a way to switch a material’s magnetic properties from ‘hard’ to ‘soft’ and back again – something which could lead to new ways of controlling electromagnetic devices.
The research will appear in the journal Nature on August 2nd and shows how a magnet can be ‘tuned’ by subjecting it to a second magnetic field, perpendicular to the original.

Magnets can be classified by their ‘hard’ or ‘soft’ magnetic properties. Hard magnets, sometimes called ‘permanent’ magnets, have fixed or ‘pinned’ domain walls which mean the material stays magnetised for a long time. Soft magnets have moveable domain walls that can be easily flipped. These materials exhibit impermanent magnetic properties.

Professor Gabriel Aeppli, Director of the LCN and a senior member of the research team, explained the significance of the research: “Whether a magnet is hard or soft determines what you can use it for. Typically, you would use a permanent magnet to fix a note to the door of your refrigerator because you want it to stay there for a long time. On the other hand, you might use a soft magnet in a motor or transformer because it would be better at adapting to the rapid changes in alternating current and would dissipate much less energy than a hard magnet.

“It is very rare to be able to continuously tune wall pinning in a magnet but we have now shown how it can be done in a model magnet at a low temperature. In the process, we demonstrate a new route to applications of magnets at higher temperatures and show how chemical disorder at the nanometre (one billionth of a meter) scale can have a huge effect on the properties of a macroscopic (centimetre scale) magnet.”

Most physical and biological systems can be thought of as disordered. Semiconductors rely on randomly placed impurities for their electrical properties and uses, while the chemical and structural impurities in magnets determine the domain wall pinning and therefore how easily their polarity can be changed.

“From a theoretical point of view, it’s been really interesting for us to see the properties of a large, disordered system being dominated to such an extent by a rare configuration of impurities,” says Professor Aeppli. “Unlike biological systems, in materials science we are used to seeing behaviour which is dominated by the average characteristics of the system. Here we can observe the massive influence of a miniscule number of chemical and structural defects.” ###

Contact: Dave Weston d.weston@ucl.ac.uk 44-020-767-97678 University College London

Work at the London Centre for Nanotechnology was funded by the UK Engineering and Physical Sciences Research Council and a Wolfson-Royal Society Research Merit Award. Additional research was also carried out at the University of Chicago.

About the London Centre for Nanotechnology: The London Centre for Nanotechnology is a joint enterprise between University College London and Imperial College London. In bringing together world-class infrastructure and leading nanotechnology research activities, the Centre aims to attain the critical mass to compete with the best facilities abroad.

Furthermore by acting as a bridge between the biomedical, physical, chemical and engineering sciences the Centre will cross the 'chip-to-cell interface' - an essential step if the UK is to remain internationally competitive in biotechnology. Website: london-nano.ucl.ac.uk

About UCL: Founded in 1826, UCL was the first English university established after Oxford and Cambridge, the first to admit students regardless of race, class, religion or gender, and the first to provide systematic teaching of law, architecture and medicine. In the government’s most recent Research Assessment Exercise, 59 UCL departments achieved top ratings of 5* and 5, indicating research quality of international excellence.

UCL is the fourth-ranked UK university in the 2006 league table of the top 500 world universities produced by the Shanghai Jiao Tong University. UCL alumni include Mahatma Gandhi (Laws 1889, Indian political and spiritual leader); Jonathan Dimbleby (Philosophy 1969, writer and television presenter); Junichiro Koizumi (Economics 1969, Prime Minister of Japan); Lord Woolf (Laws 1954, Lord Chief Justice of England & Wales); Alexander Graham Bell (Phonetics 1860s, inventor of the telephone), and members of the band Coldplay.

About the University of Chicago: Founded by oil magnate John D. Rockefeller, the University of Chicago is a private, nondenominational institution of higher learning. Scientists at the University are working at the cutting edge of virtually every field of science, from cosmological astrophysics to molecular genetics and from high-energy particle physics to psychoneuroimmunology. Seventy-nine recipients of the Nobel Prize have been researchers, students or faculty members at the University at some point in their careers. Website: uchicago.edu

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