New benchtop polymer characterization method developed

ScienceDaily (Oct. 20, 2011) — Researchers at UC Santa Barbara have developed a new and highly efficient way to characterize the structure of polymers at the nanoscale -- effectively designing a routine analytical tool that could be used by industries that rely on polymer science to innovate new products, from drug delivery gels to renewable bio-materials.

Professor Omar Saleh and graduate student Andrew Dittmore of the UCSB Materials department have successfully measured the structure and other critical parameters of a long, string-like polymer molecule -- polyethylene glycol, or PEG -- by stretching it with an instrument called magnetic tweezers.

"We attach one end of the PEG molecule to a surface, and the other to a tiny magnetic bead, then pull on the bead by applying a magnetic field," explained Saleh. "The significance is that we're able to perform the elastic measurements -- force vs. length measurement -- to see aspects of polymer structure that are hard to see in any other way, and we can do it within minutes on a benchtop apparatus."

Their research to characterize this particular polymer will lay the groundwork for developing a screening tool that could be used by a number of industries, according to Saleh's research team.

"Our measurements of PEG can be used as a baseline for comparison to other polymers, including biomolecules such as DNA, RNA and proteins, which display more complex physics," said Dittmore. "We chose to study PEG because it is an inert polymer that is biocompatible, soluble in water, and used for many technological purposes. The protocols we developed will be useful for future work with a variety of polymers, greatly expanding the versatility of the magnetic tweezers technique."

PEG is one of the most frequently used polymers in creams, cosmetics, adhesives and medicines, but its application goes beyond everyday household products. As a coating, PEG can shield against an unwanted immune response to give a medicine a stealth-like quality. To this end, it is used to enhance the effectiveness of anticancer drugs by increasing the circulation time in the body. PEG repels other molecules and is often used as a nonfouling coating for biomedical implants and biosensors that detect the presence of drugs or antibodies in blood.

In 1974, Paul Flory won the Nobel Prize in Chemistry for his theories regarding polymer structure in a solvent. Inspired by the work of Flory, and theories put forth decades earlier by UCSB materials and physics professor Philip Pincus, Saleh and Dittmore set out to develop an experiment that would validate their theories.

"Flory and de Gennes taught us that the structure of a polymer in solution depends on both the quality of solvent and also the length of the chain. Pincus extended upon this theory, and brought force into the picture as an important experimental variable," said Dittmore. "Now we have a method to directly test these ideas at the single-molecule level, using a powerful and quantitative technique."

"Until now, the most general method to obtain comparable data is to use neutron or x-ray diffraction which involves expensive national facilities such as nuclear reactors or particle accelerators. Thus, this research opens up a broad area of research that can be carried out at academic and industrial laboratories with modest resources," commented Professor Philip Pincus, Chair of Biomolecular Science and Engineering at UCSB.

The findings of Dittmore et al. were published in the journal Physical Review Letters in September. The paper establishes a framework for comparing biomolecules and synthetic polymers based on chain structure that could be further refined and translated into a laboratory tool for industry.

"Many companies are looking to replace the petroleum-based polymers they use in consumer products with polymers made from biomass, such as sugar cane or cellulose," said Professor Glenn Fredrickson, Chair of Functional Materials and Founding Director of the Mitsubishi Chemical Center for Advanced Materials at UCSB. "If their methods could be made into a compact and inexpensive screening tool for polymer properties in an industrial setting, it could be important in affecting industry transformation to producing polymers from renewable resources.

Their research was made possible by support from the National Science Foundation and was carried out at the Materials Research Laboratory: an NSF MRSEC facility at UC Santa Barbara.

"This is an excellent example of high-risk, transformative research that breaks down conventional wisdom," said Craig Hawker, Director of the Materials Research Laboratory at UCSB. "The MRL is proud to have contributed to the success of this project through a Seed program designed to fund research that will revolutionize existing fields. By establishing this technique as a powerful, new strategy for characterizing synthetic polymers, countless future studies are now possible."

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Journal Reference:

Andrew Dittmore, Dustin McIntosh, Sam Halliday, Omar Saleh. Single-Molecule Elasticity Measurements of the Onset of Excluded Volume in Poly(Ethylene Glycol). Physical Review Letters, 2011; 107 (14) DOI: 10.1103/PhysRevLett.107.148301

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Cloaking magnetic fields: First antimagnet developed

ScienceDaily (Sep. 23, 2011) — Spanish researchers have designed what they believe to be a new type of magnetic cloak, which shields objects from external magnetic fields, while at the same time preventing any magnetic internal fields from leaking outside, making the cloak undetectable.

The development of such a device, described as an 'antimagnet', could offer many beneficial applications, such as protecting a ship's hull from mines designed to detonate when a magnetic field is detected, or allowing patients with pacemakers or cochlear implants to use medical equipment.

In their study, published Sept. 23, in the Institute of Physics and German Physical Society's New Journal of Physics, researchers have proved that such a cloak could be built using practical and available materials and technologies, and used to develop an array of applications.

Take, for example, a patient with a pacemaker undergoing an MRI scan. If an MRI's large magnetic field interacts with the pacemaker, it can cause serious damage to both the device and the patient. The metal in the pacemaker could also interact with and distort the MRI's large magnetic field, affecting the machine's detection capabilities.

The researchers, from Universitat Autònoma de Barcelona, are aware that the technology could also be used by criminals to dodge security systems, for example in airports and shops, but they are confident that the new research could benefit society in a positive way, while the risks could be minimized by informing security officials about potential devices, enabling them to anticipate and neutralize problems.

Lead author, Professor Alvar Sanchez, said, "The ideas of this device and their potential applications are far-reaching; however it is conceivable that they could be used for reducing the magnetic signature of forbidden objects, with the consequent threat to security. For these reasons, this research could be taken into account by security officials in order to design safer detection systems and protocols."

The antimagnet has been designed to consist of several layers. The inner layer would consist of a superconducting material that would function to stop a magnetic field from leaking outside of the cloak, which would be very useful to cloak certain metals.

A downside to using this material, however, is that it would distort an external magnetic field placed over the cloak, making it detectable, so the device would need to be combined with several outer layers of metamaterials, which have varying levels of magnetic field permeability, to correct this distortion and leave the magnetic field undisturbed.

The researchers demonstrated the feasibility of the cloak using computer simulations of a ten-layered cylindrical device cloaking a single small magnet.

Impressively, the researchers also showed that the cloak could take on other shapes and function when the cylinder was not fully enclosed, meaning that applications for pacemakers and cochlear implants are even more feasible, given that they require wires to connect to other parts of the body.

"We indeed believe, and hope, that some laboratories could start constructing an antimagnet soon. Of the two components, superconductors are readily available, for example in cylindrical shape, and the key point would be to make the magnetic layers with the desired properties. This may take a bit of work but in principle the ingredients are there," continued Professor Sanchez.

An Institute of Physics spokesperson said, "The research group have put forward a novel and, most importantly, conceivable plan for a magnetic cloak. The obvious next step will be to translate design into fabrication so some of the wide-ranging applications can be realised."

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Institute of Physics, via EurekAlert!, a service of AAAS.

Journal Reference:

Alvaro Sanchez, Carles Navau, Jordi Prat-Camps, Du-Xing Chen. Antimagnets: controlling magnetic fields with superconductor–metamaterial hybrids. New Journal of Physics, 2011; 13 (9): 093034 DOI: 10.1088/1367-2630/13/9/093034

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

Cloaking magnetic fields: First antimagnet developed

ScienceDaily (Sep. 23, 2011) — Spanish researchers have designed what they believe to be a new type of magnetic cloak, which shields objects from external magnetic fields, while at the same time preventing any magnetic internal fields from leaking outside, making the cloak undetectable.

The development of such a device, described as an 'antimagnet', could offer many beneficial applications, such as protecting a ship's hull from mines designed to detonate when a magnetic field is detected, or allowing patients with pacemakers or cochlear implants to use medical equipment.

In their study, published Sept. 23, in the Institute of Physics and German Physical Society's New Journal of Physics, researchers have proved that such a cloak could be built using practical and available materials and technologies, and used to develop an array of applications.

Take, for example, a patient with a pacemaker undergoing an MRI scan. If an MRI's large magnetic field interacts with the pacemaker, it can cause serious damage to both the device and the patient. The metal in the pacemaker could also interact with and distort the MRI's large magnetic field, affecting the machine's detection capabilities.

The researchers, from Universitat Autònoma de Barcelona, are aware that the technology could also be used by criminals to dodge security systems, for example in airports and shops, but they are confident that the new research could benefit society in a positive way, while the risks could be minimized by informing security officials about potential devices, enabling them to anticipate and neutralize problems.

Lead author, Professor Alvar Sanchez, said, "The ideas of this device and their potential applications are far-reaching; however it is conceivable that they could be used for reducing the magnetic signature of forbidden objects, with the consequent threat to security. For these reasons, this research could be taken into account by security officials in order to design safer detection systems and protocols."

The antimagnet has been designed to consist of several layers. The inner layer would consist of a superconducting material that would function to stop a magnetic field from leaking outside of the cloak, which would be very useful to cloak certain metals.

A downside to using this material, however, is that it would distort an external magnetic field placed over the cloak, making it detectable, so the device would need to be combined with several outer layers of metamaterials, which have varying levels of magnetic field permeability, to correct this distortion and leave the magnetic field undisturbed.

The researchers demonstrated the feasibility of the cloak using computer simulations of a ten-layered cylindrical device cloaking a single small magnet.

Impressively, the researchers also showed that the cloak could take on other shapes and function when the cylinder was not fully enclosed, meaning that applications for pacemakers and cochlear implants are even more feasible, given that they require wires to connect to other parts of the body.

"We indeed believe, and hope, that some laboratories could start constructing an antimagnet soon. Of the two components, superconductors are readily available, for example in cylindrical shape, and the key point would be to make the magnetic layers with the desired properties. This may take a bit of work but in principle the ingredients are there," continued Professor Sanchez.

An Institute of Physics spokesperson said, "The research group have put forward a novel and, most importantly, conceivable plan for a magnetic cloak. The obvious next step will be to translate design into fabrication so some of the wide-ranging applications can be realised."

Recommend this story on Facebook, Twitter,
and Google +1:

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Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Institute of Physics, via EurekAlert!, a service of AAAS.

Journal Reference:

Alvaro Sanchez, Carles Navau, Jordi Prat-Camps, Du-Xing Chen. Antimagnets: controlling magnetic fields with superconductor–metamaterial hybrids. New Journal of Physics, 2011; 13 (9): 093034 DOI: 10.1088/1367-2630/13/9/093034

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

High performance electric motorcycle developed

ScienceDaily (May 23, 2011) — A group of engineers at Carlos III University of Madrid (UC3M) has developed a prototype of a high-performance electric motorcycle, which has recently participated in the first electric motorcycle world championship.

This project, known as e-Moto, was created and developed by LGN Tech Design, a spin-off company that has its origins in a line of research begun in the Laboratorio de Máquinas (MAQLAB -- Machine Laboratory) of UC3M and receives support from the University's Vice-Chancellor's Office of Research through the Business Incubator UC3M Science Park. "The technology that we have developed is a result of the design of a platform for the modeling, analysis and evolution of racing motorcycles, which was then applied to the development of the e-Moto," comments the head of the MAQLAB, Professor Juan Carlos García Prada, of the Mechanical Engineering Department at UC3M.

The prototype of the e-Moto recently participated in the first FIM E-Power electric motorcycle world championship (100% electric), organized by the International Motorcycling Federation. The model came in third, a position of merit according to its creators, who point out that, although there were only three contestants on the track at the Magny-Cours circuit in France, the motorcycle managed to finish the race with no mechanical problems whatsoever.

This is a vehicle that was conceived as an electric motorcycle from the very beginning, with battery recharging systems that offer quite remarkable results, and which are similar to those of an automobile. Among the technical features of the prototype, its light weight (145 Kg.) in comparison with other existing models stands out, as does its alternating current motor, which boasts a maximum 95 horsepower. It also features a system for recharging its batteries when braking and an innovative front suspension based on a system that has already been tested in other research projects.

A global e-motorcycle

This first prototype, according to its promoters, is the beginning of the worldwide development of electric motorcycles that goes beyond current electric motorcycles, the majority of which are of the scooter type. The creators of this project recognize that in this phase of the development of Spanish electric motorcycles, the support of public and private institutions is needed, in order to allow for the evolution of what will be the first Spanish company to develop high performance electric motorcycles.

The idea is that an electric motorcycle offers great advantages over a conventional motorcycle. "The most important thing, when considering its use in society, is the nearly complete elimination of gasses and the considerable reduction of noise and vibrations," explains Juan Carlos García Prada. Summing up, this is a Spanish research project that attempts to take advantage of advanced technology in order to create a more sustainable future.

The results of the different projects carried out within the university setting have lead to the creation of the UC3M LGN Tech Design Chaired Professorship. "We have created this professorship in order to offer technological support to the students who have developed this project and who have carried out other research projects as well," comments Professor García Prada. A direct consequence of all of this interrelated activity by the university and the productive world is the stimulation of new teaching (through students' final projects, practicums, etc), as well as of R + D within UC3M in the automobile components area, within the context of the potentially huge market, considering both the institutional demand and that of society at large.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Universidad Carlos III de Madrid - Oficina de Información Científica.

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Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

'Biological circuit' components developed; New microscope technique for measuring them

ScienceDaily (June 9, 2011) — Electrical engineers have long been toying with the idea of designing biological molecules that can be directly integrated into electronic circuits. University of Pennsylvania researchers have developed a way to form these structures so they can operate in open-air environments, and, more important, have developed a new microscope technique that can measure the electrical properties of these and similar devices.

The research was conducted by Dawn Bonnell, Trustee Chair Professor and director of the Nano/Bio Interface Center, graduate students Kendra Kathan-Galipeau and Maxim Nikiforov and postdoctoral fellow Sanjini Nanayakkara, all of the Department of Materials Science and Engineering in Penn's School of Engineering and Applied Science. They collaborated with assistant professor Bohdana Discher of the Department of Biophysics and Biochemistry at Penn's Perelman School of Medicine and Paul A. O'Brien, a graduate student in Penn's Biotechnology Masters Program.

Their work was published in the journal ACS Nano.

The development involves artificial proteins, bundles of peptide helices with a photoactive molecule inside. These proteins are arranged on electrodes, which are common feature of circuits that transmit electrical charges between metallic and non-metallic elements. When light is shined on the proteins, they convert photons into electrons and pass them to the electrode.

"It's a similar mechanism to what happens when plants absorb light, except in that case the electron is used for some chemistry that creates energy for the plant," Bonnell said. "In this case, we want to use the electron in electrical circuits."

Similar peptide assemblies had been studied in solution before by several groups and had been tested to show that they indeed react to light. But there was no way to quantify their ambient electrical properties, particularly capacitance, the amount of electrical charge the assembly holds.

"It's necessary to understand these kinds of properties in the molecules in order to make devices out of them. We've been studying silicon for 40 years, so we know what happens to electrons there," Bonnell said. "We didn't know what happens to electrons on dry electrodes with these proteins; we didn't even know if they would remain photoactive when attached to an electrode."

Designing circuits and devices with silicon is inherently easier than with proteins. The electrical properties of a large chunk of a single element can be measured and then scaled down, but complex molecules like these proteins cannot be scaled up. Diagnostic systems that could measure their properties with nanometer sensitivity simply did not exist.

The researchers therefore needed to invent both a new way of a measuring these properties and a controlled way of making the photovoltaic proteins that would resemble how they might eventually be incorporated into devices in open-air, everyday environments, rather than swimming in a chemical solution.

To solve the first problem, the team developed a new kind of atomic force microscope technique, known as torsional resonance nanoimpedance microscopy. Atomic force microscopes operate by bringing an extremely narrow silicon tip very close to a surface and measuring how the tip reacts, providing a spatial sensitivity of a few nanometers down to individual atoms.

"What we've done in our version is to use a metallic tip and put an oscillating electric field on it. By seeing how electrons react to the field, we're able to measure more complex interactions and more complex properties, such as capacitance," Bonnell said.

Bohdana Discher's group designed the self-assembling proteins much as they had done before but took the additional step of stamping them onto sheets of graphite electrodes. This manufacturing principle and the ability to measure the resulting devices could have a variety of applications.

"Photovoltaics -- solar cells -- are perhaps the easiest to imagine, but where this work is going in the shorter term is biochemical sensors," Bonnell said.

Instead of reacting to photons, proteins could be designed to produce a charge when in the presence of a certain toxins, either changing color or acting as a circuit element in a human-scale gadget.

This research was supported by the Nano/Bio Interface Center and the National Science Foundation.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Pennsylvania.

Journal Reference:

Kendra Kathan-Galipeau, Sanjini Nanayakkara, Paul A. O’Brian, Maxim Nikiforov, Bohdana M. Discher, Dawn A. Bonnell. Direct Probe of Molecular Polarization inDe NovoProtein–Electrode Interfaces. ACS Nano, 2011; 110603081000090 DOI: 10.1021/nn200887n

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

'Biological circuit' components developed; New microscope technique for measuring them

ScienceDaily (June 9, 2011) — Electrical engineers have long been toying with the idea of designing biological molecules that can be directly integrated into electronic circuits. University of Pennsylvania researchers have developed a way to form these structures so they can operate in open-air environments, and, more important, have developed a new microscope technique that can measure the electrical properties of these and similar devices.

The research was conducted by Dawn Bonnell, Trustee Chair Professor and director of the Nano/Bio Interface Center, graduate students Kendra Kathan-Galipeau and Maxim Nikiforov and postdoctoral fellow Sanjini Nanayakkara, all of the Department of Materials Science and Engineering in Penn's School of Engineering and Applied Science. They collaborated with assistant professor Bohdana Discher of the Department of Biophysics and Biochemistry at Penn's Perelman School of Medicine and Paul A. O'Brien, a graduate student in Penn's Biotechnology Masters Program.

Their work was published in the journal ACS Nano.

The development involves artificial proteins, bundles of peptide helices with a photoactive molecule inside. These proteins are arranged on electrodes, which are common feature of circuits that transmit electrical charges between metallic and non-metallic elements. When light is shined on the proteins, they convert photons into electrons and pass them to the electrode.

"It's a similar mechanism to what happens when plants absorb light, except in that case the electron is used for some chemistry that creates energy for the plant," Bonnell said. "In this case, we want to use the electron in electrical circuits."

Similar peptide assemblies had been studied in solution before by several groups and had been tested to show that they indeed react to light. But there was no way to quantify their ambient electrical properties, particularly capacitance, the amount of electrical charge the assembly holds.

"It's necessary to understand these kinds of properties in the molecules in order to make devices out of them. We've been studying silicon for 40 years, so we know what happens to electrons there," Bonnell said. "We didn't know what happens to electrons on dry electrodes with these proteins; we didn't even know if they would remain photoactive when attached to an electrode."

Designing circuits and devices with silicon is inherently easier than with proteins. The electrical properties of a large chunk of a single element can be measured and then scaled down, but complex molecules like these proteins cannot be scaled up. Diagnostic systems that could measure their properties with nanometer sensitivity simply did not exist.

The researchers therefore needed to invent both a new way of a measuring these properties and a controlled way of making the photovoltaic proteins that would resemble how they might eventually be incorporated into devices in open-air, everyday environments, rather than swimming in a chemical solution.

To solve the first problem, the team developed a new kind of atomic force microscope technique, known as torsional resonance nanoimpedance microscopy. Atomic force microscopes operate by bringing an extremely narrow silicon tip very close to a surface and measuring how the tip reacts, providing a spatial sensitivity of a few nanometers down to individual atoms.

"What we've done in our version is to use a metallic tip and put an oscillating electric field on it. By seeing how electrons react to the field, we're able to measure more complex interactions and more complex properties, such as capacitance," Bonnell said.

Bohdana Discher's group designed the self-assembling proteins much as they had done before but took the additional step of stamping them onto sheets of graphite electrodes. This manufacturing principle and the ability to measure the resulting devices could have a variety of applications.

"Photovoltaics -- solar cells -- are perhaps the easiest to imagine, but where this work is going in the shorter term is biochemical sensors," Bonnell said.

Instead of reacting to photons, proteins could be designed to produce a charge when in the presence of a certain toxins, either changing color or acting as a circuit element in a human-scale gadget.

This research was supported by the Nano/Bio Interface Center and the National Science Foundation.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Pennsylvania.

Journal Reference:

Kendra Kathan-Galipeau, Sanjini Nanayakkara, Paul A. O’Brian, Maxim Nikiforov, Bohdana M. Discher, Dawn A. Bonnell. Direct Probe of Molecular Polarization inDe NovoProtein–Electrode Interfaces. ACS Nano, 2011; 110603081000090 DOI: 10.1021/nn200887n

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

Hardware encryption developed for new computer memory technology

ScienceDaily (May 18, 2011) — Security concerns are one of the key obstacles to the adoption of new non-volatile main memory (NVMM) technology in next-generation computers, which would improve computer start times and boost memory capacity. But now researchers from North Carolina State University have developed new encryption hardware for use with NVMM to protect personal information and other data.

NVMM technologies, such as phase-change memory, hold great promise to replace conventional dynamic random access memory (DRAM) in the main memory of computers. NVMM would allow computers to start instantly, and can fit more memory into the same amount of space used by existing technologies. However, NVMM poses a security risk.

Conventional DRAM main memory does not store data once the computer is turned off. That means, for example, that it doesn't store your credit card number and password after an online shopping spree. NVMM, on the other hand, retains all user data in main memory even years after the computer is turned off. This feature could give criminals access to your personal information or other data if your laptop or smart phone were stolen. And, because the data in the NVMM is stored in main memory, it cannot be encrypted using software. Software cannot manage main memory functions, because software itself operates in main memory.

NC State researchers have developed a solution using a hardware encryption system called i-NVMM.

"We could use hardware to encrypt everything," explains Dr. Yan Solihin, associate professor of electrical and computer engineering at NC State and co-author of a paper describing i-NVMM, "but then the system would run very slowly -- because it would constantly be encrypting and decrypting data.

"Instead, we developed an algorithm to detect data that is likely not needed by the processor. This allows us to keep 78 percent of main memory encrypted during typical operation, and only slows the system's performance by 3.7 percent."

The i-NVMM tool has two additional benefits as well. First, its algorithm also detects idleness. That means any data not currently in use -- such as your credit card number -- is automatically encrypted. This makes i-NVMM even more secure than DRAM. Second, while 78 percent of the main memory is encrypted when the computer is in use, the remaining 22 percent is encrypted when the computer is powered down.

"Basically, unless someone accesses your computer while you're using it, all of your data is protected," Solihin says.

i-NVMM relies on a self-contained encryption engine that is incorporated into a computer's memory module -- and does not require changes to the computer's processors. That means it can be used with different processors and different systems.

"We're now seeking industry partners who are interested in this technology," Solihin says.

The paper, "i-NVMM: A Secure Non-Volatile Main Memory System with Incremental Encryption," will be presented June 6 at the International Symposium on Computer Architecture (ISCA) in San Jose, Calif. The paper was co-authored by Dr. Siddhartha Chhabra, a former Ph.D. student at NC State. The research was supported, in part, by the National Science Foundation.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by North Carolina State University.

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

Hardware encryption developed for new computer memory technology

ScienceDaily (May 18, 2011) — Security concerns are one of the key obstacles to the adoption of new non-volatile main memory (NVMM) technology in next-generation computers, which would improve computer start times and boost memory capacity. But now researchers from North Carolina State University have developed new encryption hardware for use with NVMM to protect personal information and other data.

NVMM technologies, such as phase-change memory, hold great promise to replace conventional dynamic random access memory (DRAM) in the main memory of computers. NVMM would allow computers to start instantly, and can fit more memory into the same amount of space used by existing technologies. However, NVMM poses a security risk.

Conventional DRAM main memory does not store data once the computer is turned off. That means, for example, that it doesn't store your credit card number and password after an online shopping spree. NVMM, on the other hand, retains all user data in main memory even years after the computer is turned off. This feature could give criminals access to your personal information or other data if your laptop or smart phone were stolen. And, because the data in the NVMM is stored in main memory, it cannot be encrypted using software. Software cannot manage main memory functions, because software itself operates in main memory.

NC State researchers have developed a solution using a hardware encryption system called i-NVMM.

"We could use hardware to encrypt everything," explains Dr. Yan Solihin, associate professor of electrical and computer engineering at NC State and co-author of a paper describing i-NVMM, "but then the system would run very slowly -- because it would constantly be encrypting and decrypting data.

"Instead, we developed an algorithm to detect data that is likely not needed by the processor. This allows us to keep 78 percent of main memory encrypted during typical operation, and only slows the system's performance by 3.7 percent."

The i-NVMM tool has two additional benefits as well. First, its algorithm also detects idleness. That means any data not currently in use -- such as your credit card number -- is automatically encrypted. This makes i-NVMM even more secure than DRAM. Second, while 78 percent of the main memory is encrypted when the computer is in use, the remaining 22 percent is encrypted when the computer is powered down.

"Basically, unless someone accesses your computer while you're using it, all of your data is protected," Solihin says.

i-NVMM relies on a self-contained encryption engine that is incorporated into a computer's memory module -- and does not require changes to the computer's processors. That means it can be used with different processors and different systems.

"We're now seeking industry partners who are interested in this technology," Solihin says.

The paper, "i-NVMM: A Secure Non-Volatile Main Memory System with Incremental Encryption," will be presented June 6 at the International Symposium on Computer Architecture (ISCA) in San Jose, Calif. The paper was co-authored by Dr. Siddhartha Chhabra, a former Ph.D. student at NC State. The research was supported, in part, by the National Science Foundation.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by North Carolina State University.

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

High performance electric motorcycle developed

ScienceDaily (May 23, 2011) — A group of engineers at Carlos III University of Madrid (UC3M) has developed a prototype of a high-performance electric motorcycle, which has recently participated in the first electric motorcycle world championship.

This project, known as e-Moto, was created and developed by LGN Tech Design, a spin-off company that has its origins in a line of research begun in the Laboratorio de Máquinas (MAQLAB -- Machine Laboratory) of UC3M and receives support from the University's Vice-Chancellor's Office of Research through the Business Incubator UC3M Science Park. "The technology that we have developed is a result of the design of a platform for the modeling, analysis and evolution of racing motorcycles, which was then applied to the development of the e-Moto," comments the head of the MAQLAB, Professor Juan Carlos García Prada, of the Mechanical Engineering Department at UC3M.

The prototype of the e-Moto recently participated in the first FIM E-Power electric motorcycle world championship (100% electric), organized by the International Motorcycling Federation. The model came in third, a position of merit according to its creators, who point out that, although there were only three contestants on the track at the Magny-Cours circuit in France, the motorcycle managed to finish the race with no mechanical problems whatsoever.

This is a vehicle that was conceived as an electric motorcycle from the very beginning, with battery recharging systems that offer quite remarkable results, and which are similar to those of an automobile. Among the technical features of the prototype, its light weight (145 Kg.) in comparison with other existing models stands out, as does its alternating current motor, which boasts a maximum 95 horsepower. It also features a system for recharging its batteries when braking and an innovative front suspension based on a system that has already been tested in other research projects.

A global e-motorcycle

This first prototype, according to its promoters, is the beginning of the worldwide development of electric motorcycles that goes beyond current electric motorcycles, the majority of which are of the scooter type. The creators of this project recognize that in this phase of the development of Spanish electric motorcycles, the support of public and private institutions is needed, in order to allow for the evolution of what will be the first Spanish company to develop high performance electric motorcycles.

The idea is that an electric motorcycle offers great advantages over a conventional motorcycle. "The most important thing, when considering its use in society, is the nearly complete elimination of gasses and the considerable reduction of noise and vibrations," explains Juan Carlos García Prada. Summing up, this is a Spanish research project that attempts to take advantage of advanced technology in order to create a more sustainable future.

The results of the different projects carried out within the university setting have lead to the creation of the UC3M LGN Tech Design Chaired Professorship. "We have created this professorship in order to offer technological support to the students who have developed this project and who have carried out other research projects as well," comments Professor García Prada. A direct consequence of all of this interrelated activity by the university and the productive world is the stimulation of new teaching (through students' final projects, practicums, etc), as well as of R + D within UC3M in the automobile components area, within the context of the potentially huge market, considering both the institutional demand and that of society at large.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Universidad Carlos III de Madrid - Oficina de Información Científica.

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Strong, tough and now cheap: New way to process metallic glass developed

ScienceDaily (May 13, 2011) — Stronger than steel or titanium -- and just as tough -- metallic glass is an ideal material for everything from cell-phone cases to aircraft parts. Now, researchers at the California Institute of Technology (Caltech) have developed a new technique that allows them to make metallic-glass parts utilizing the same inexpensive processes used to produce plastic parts. With this new method, they can heat a piece of metallic glass at a rate of a million degrees per second and then mold it into any shape in just a few milliseconds.

"We've redefined how you process metals," says William Johnson, the Ruben F. and Donna Mettler Professor of Engineering and Applied Science. "This is a paradigm shift in metallurgy." Johnson leads a team of researchers who are publishing their findings in the May 13 issue of the journal Science.

"We've taken the economics of plastic manufacturing and applied it to a metal with superior engineering properties," he says. "We end up with inexpensive, high-performance, precision net-shape parts made in the same way plastic parts are made -- but made of a metal that's 20 times stronger and stiffer than plastic." A net-shape part is a part that has acquired its final shape.

Metallic glasses, which were first discovered at Caltech in 1960 and later produced in bulk form by Johnson's group in the early 1990s, are not transparent like window glass. Rather, they are metals with the disordered atomic structure of glass. While common glasses are generally strong, hard, and resistant to permanent deformation, they tend to easily crack or shatter. Metals tend to be tough materials that resist cracking and brittle fracture -- but they have limited strength. Metallic glasses, Johnson says, have an exceptional combination of both the strength associated with glass and the toughness of metals.

To make useful parts from a metallic glass, you need to heat the material until it reaches its glass-transition phase, at about 500-600 degrees C. The material softens and becomes a thick liquid that can be molded and shaped. In this liquid state, the atoms tend to spontaneously arrange themselves to form crystals. Solid glass is formed when the molten material refreezes into place before its atoms have had enough time to form crystals. By avoiding crystallization, the material keeps its amorphous structure, which is what makes it strong.

Common window glass and certain plastics take from minutes to hours -- or longer -- to crystallize in this molten state, providing ample time for them to be molded, shaped, cooled, and solidified. Metallic glasses, however, crystallize almost immediately once they are heated to the thick-liquid state. Avoiding this rapid crystallization is the main challenge in making metallic-glass parts.

Previously, metallic-glass parts were produced by heating the metal alloy above the melting point of the crystalline phase -- typically over 1,000 degrees C. Then, the molten metal is cast into a steel mold, where it cools before crystallizing. But problems arise because the steel molds are usually designed to withstand temperatures of only around 600 degrees C. As a result, the molds have to be frequently replaced, making the process rather expensive. Furthermore, at 1,000 degrees C, the liquid is so fluid that it tends to splash and break up, creating parts with flow defects.

If the solid metallic glass is heated to about 500-600 degrees C, it reaches the same fluidity that liquid plastic needs to have when it's processed. But it takes time for heat to spread through a metallic glass, and by the time the material reaches the proper temperature throughout, it has already crystallized.

So the researchers tried a new strategy: to heat and process the metallic glass extremely quickly. Johnson's team discovered that, if they were fast enough, they could heat the metallic glass to a liquid state that's fluid enough to be injected into a mold and allowed to freeze -- all before it could crystallize.

To heat the material uniformly and rapidly, they used a technique called ohmic heating. The researchers fired a short and intense pulse of electrical current to deliver an energy surpassing 1,000 joules in about 1 millisecond -- about one megawatt of power -- to heat a small rod of the metallic glass.

The current pulse heats the entire rod -- which was 4 millimeters in diameter and 2 centimeters long -- at a rate of a million degrees per second. "We uniformly heat the glass at least a thousand times faster than anyone has before," Johnson says. Taking only about half a millisecond to reach the right temperature, the now-softened glass could be injected into a mold and cooled -- all in milliseconds. To demonstrate the new method, the researchers heated a metallic-glass rod to about 550 degrees C and then shaped it into a toroid in less than 40 milliseconds. Despite being formed in open air, the molded toroid is free of flow defects and oxidation.

In addition, this process allows researchers to study these materials in their molten states, which was never before possible. For example, by heating the material before it can crystallize, researchers can examine the crystallization process itself on millisecond time scales. The new technique, called rapid discharge forming, has been patented and is being developed for commercialization, Johnson says. In 2010, he and his colleagues started a company, Glassimetal Technology, to commercialize novel metallic-glass alloys using this kind of plastic-forming technology.

The other authors on the Science paper, "Beating crystallization in glass-forming metals by millisecond heating and processing," are Caltech's Georg Kaltenboeck, Marios D. Demetriou, Joseph P. Schramm, Xiao Liu, Konrad Samwer (a visiting associate from the University of Gottingen, Germany), C. Paul Kim, and Douglas C. Hofmann. This research benefited from support by the II-VI Foundation.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by California Institute of Technology. The original article was written by Marcus Woo.

Journal Reference:

W. L. Johnson, G. Kaltenboeck, M. D. Demetriou, J. P. Schramm, X. Liu, K. Samwer, C. P. Kim, D. C. Hofmann. Beating Crystallization in Glass-Forming Metals by Millisecond Heating and Processing. Science, 2011; 332 (6031): 828 DOI: 10.1126/science.1201362

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