Silicon Melt in Reverse!

The fact that many materials change state at a given temperature is a basic chemistry concept. However, scientists at MIT has found that silicon can exhibit a strange property of "retrograde melting" under high concentrations of certain metals dissolved in it. Basically, the compound of silicon melts at extremely low temperatures. This implies a lowered cost of manufacturing of some sillicon-based devices, new silicon nanowire structures and etc.

Reference:
Steve Hudelson, Bonna K. Newman, Sarah Bernardis, David P. Fenning, Mariana I. Bertoni, Matthew A. Marcus, Sirine C. Fakra, Barry Lai, Tonio Buonassisi. Retrograde Melting and Internal Liquid Gettering in Silicon. Advanced Materials, 2010; DOI: 10.1002/adma.200904344

Electrical Current to Nanoscale System

Material scientists have demonstrated the transduction of optical radiation to electrical current in a molecular circuit. The system with an array of nano-sized molecules respond to electromagnetic waves. Therefore, it simplifies to a higher efficiency in energy harvesting nano-sized circuit. A potential application of photovoltaic circuits include data storage where the data corresponding to wavelengths of light. A new series of devices in which plasmon-controlled electrical properties of a single molecule can be designed with diverse applications such as plasmonic circuits and energy harvesting devices.

Reference: Science Daily

Growing Nanowires

Researchers have developed nanowire 'growing technology' which opens the door for faster, smaller microchips and lower power electronics. 3-D microchips, vertical stack of circuitry, is possible with this new discovery.

Reference: Science Daily

Paper + Nanotechnology = Greater Power

Scientists have made batteries and supercapacitors with little more than ordinary office paper and some carbon and silver nanomaterials. Lightweight printable batteries is within grasp to be molded into computers, cell phones or solar panels. At the nano-scale, paper is a tangled matrix of fibers where the surface area helps inks stick. The paper acts as a scaffold, and the carbon nanotubes act as electrodes that electrolytes in solution react with. This nanotube-paper combination offers a lightweight alternative to traditional energy storage devices that rely on metals. Calculations indicate that conductive paper coated with a kilogram of the carbon nano-tubes is more efficient than plastic-based flat energy-storage devices. Power storage is an important aspect of the power crisis.

Reference: Wired

Spot Nanoparticles

There is a growing interest in detecting nanoparticles and nanotechnologists are racing to build devices that can detect and characterise these particles. One method is having resonating devices that changes when a nanoparticle is bounced off the surface, measured by a laser. However this method is only ideal in certain cases and positions. Researchers from Washington University have a new vibrating micro-mushroom device that promises greater reliability in detecting nanoparticles.

Reference:
arxiv.org/abs/0912.0078

Medical Imaging Improvement with Nanoparticles

Researchers from National Institute of Standards and Technology have discovered a method of using nano-particles to illuminate the cellular interior to reveal its slow processes. The quantum dot nano-particle glows when exposed to light. When coated with organic materials, scientists can manipulate the particle to attract to specific proteins to be examined. The research team focused primarily on characterizing quantum dot properties to target protein inside blood cells to study. However, there are concerns about toxicity and other properties of the nano-particles.

Reference:
Kang et al. Probing dynamic fluorescence properties of single and clustered quantum dots toward quantitative biomedical imaging of cells. Wiley Interdisciplinary Reviews Nanomedicine and Nanobiotechnology, 2009 DOI: 10.1002/wnan.62

mNPs to Diagnose, Monitor and Treat

Magnetic nano-particles can play a critical role in developing one-stop tools to simultaneously diagnose, monitor and treat a range of common diseases and injuries. Multifunctional particles are being researched and developed to carry signal-generated sub-molecules and drugs. External magnetic forces create a medical means of confirming specific ailments and automatically release healing drugs within a living system.

Reference: Science Daily

Nanofibre Solar Power

Researchers found a new way to make solar power more cheaper and flexible to use. The nano-scale wires built around optical fibres allow more surface area for light to interact with, which improves cell efficiency. Using this technology, photovoltaic generators are foldable, concealable and mobile. Traditionally, silicon based solar cells are most efficient because it absorbs the most light. The new method starts with commerical optical fibre without outer layer and wraps zinc oxide nanowires around the fibre. In addition, light only needs to enter at the ends of the fibre, making it space efficient.

IBM Starts Genetic Sequencing

IBM is working on prototype DNA-processing electronics that feeds DNA through a nanopore, measuring the electrical properties of the chemicals at a more precise manner.

IBM's approach uses a flat device about 250 nanometers with a thin alternating layers of metal and a material called a dielectric. The nanopore is bored through these layers using an electron beam from a tunneling electron microscope. On one side of the layer is the DNA, unzipped from its familiar double-helix configuration with two strands of matched bases into a single strand with single bases. The strand is pulled through the nanopore by an electrical field that attracts the negatively charged strand. But in the nanopore, some layers are electrically switched on to fix the strand in place for a tick of an electronic clock while another layer makes its measurement.

Reference: Cnet

Magnetism Turns Drugs On or Off

Many medical conditions require medications that is taken over a long period of time at specific quantities. This process is time consuming and current delivery techniques are not fully reliable. Researchers have created a small device that contains the drugs in a specially engineered membrane, embedded with nano-particles with minerals that have magnetic properties. When a magnetic field is turned on outside the body, the nano-particles heat up and causes the membrane to fall apart temporally, allowing drug particles to go through. Turning the magnetic field has the opposite effect and the membrane resumes stability. This technology has the potential to provide precise, repeated, long-term, on-demand delivery of drugs for a number of medical applications.

Reference:
Todd Hoare, Jesus Santamaria, Gerardo F. Goya, Silvia Irusta, Debora Lin, Samantha Lau, Robert Padera, Robert Langer, Daniel S. Kohane. A Magnetically Triggered Composite Membrane for On-Demand Drug Delivery. Nano Letters, 2009; DOI: 10.1021/nl9018935

Graphitic Memory

Researchers have advanced graphite's potential as a mass data storage medium and potentially reprogrammable gate arrays that will revolutionize circuit logic design. In the online journal ACS Nano, Alexander Sinitskii show lithographic techniques to deposite .10-nanometer stripes of amorphous graphite onto silicon - creation of nonvolile memory. Graphite makes a good, dense, reliable memory that works at low voltages. It is also impervious to a wide temperature range and radiation (space and military uses).

Reference: Science Daily

Bicycle with Nanotechnology

There are companies that pursue high-end bicycles with nanotechnology: BH Bicycles, BMC and Pinarello. The BH G4 bike uses carbon nanotubes as filler material between the carbon fibers. There is no real evidence or claim that states that the bicycle is stronger or lighter after using nanotechnology. BMC has the same approach but vaguely states that "the carbon nanotubes are 20% stronger for practically the same weight." They did not define a definition for stronger nor is the word practically any helpful in describing the situation. Pinarello on the other hand says their bicycle can prevent impacts and sudden breakage. Where is the science and more reliable claims about the benefits of using nanotechnology on bicycles?

Reference: IEEE Spectrum

Nanolaser Key "Spaser"

It is thinnest laser that can emit visible light.

It represents an important aspect for possible future innovations and technological development. This opens the door for fields such as hyper-lenses that create more powerful sensors and microscopes branching off from nano-photonic technology. Based on clouds of electrons called "surface plasmons", tiny spasers are created.

A detailed paper describing this research is posted online in the journal Nature, reporting on work done by researchers at Purdue Norfolk State University and Cornell University.

Reference: www.sciencedaily.com