Friday, July 31, 2009

One of the first things that come to mind when thinking about Harry Potter and his cloak is … invisibility. Now researchers in Spain have developed a device that makes objects invisible under a certain kind of light. Called 'dc metamaterial', the device brings the inside of the magnetic field down to zero but does not change the exterior field.

Staying in the realm of fantasy and science fiction, ‘transparent aluminium’ previously only existed in the movie Star Trek IV, but the real material is an exotic new state of matter with implications for planetary science and nuclear fusion. Oxford scientists have created a transparent form of aluminium by bombarding the metal with the world’s most powerful soft X-ray laser.

By studying gold nanoparticles with highly uniform sizes and shapes, scientists now understand how they lose energy, a key step towards producing nanoscale detectors for weighing any single atom. Such ultrasensitive measurements could ultimately be used in areas such as medical research and diagnostics, enabling the detection of minuscule disease-causing agents such as viruses and prions at the single molecule level.

An interesting development in nanoparticle synthesis is the concept of an 'evolutionary tree'. The tree not only displays the relationship between different shapes, but also offers designing principles for producing more complex shapes by crossing over different pathways during nanoparticle growth.

evolutionary tree for nanoparticles

Driven by the vision of our society one day being basically self-propelled, a team of University of Houston scientists has set out to both amplify and provoke that potential in materials known as piezoelectrics, which naturally produce electricity when literally subjected to strain. The goal is to use piezoelectrics to create nanodevices that can power electronics, such as cell phones, MP3 players and even biomedical implants.

Researchers are working on ways to make lasers smaller and smaller. This ultimately opens up possibilities for using nanoscale lasers to significantly improve the performance of computers and speed up Internet access.

Researchers at UC Riverside report the first direct observation and controlled creation of one- and two-dimensional ripples in graphene sheets. This study is first to experimentally quantify thermal contraction of graphene. Using simple thermal manipulation, the researchers produced the ripples, and controlled their orientation, wavelength and amplitude. Another research team provides two new reasons for using graphene ribbons as interconnects in future computer chips. They found that in widths as narrow as 16 nanometers, graphene has a current carrying capacity approximately a thousand times greater than copper – while providing improved thermal conductivity.

Nanoparticles are being developed to perform a wide range of medical uses – imaging tumors, carrying drugs, delivering pulses of heat. Rather than settling for just one of these, researchers at the University of Washington have combined two nanoparticles in one tiny package. The result is the first structure that creates a multipurpose nanotechnology tool for medical imaging and therapy.

In the classic fairy tale, “The Emperor’s New Clothes,” Hans Christian Andersen uses the eyes of a child to challenge conventional wisdom and help others to see more clearly. In similar fashion, researchers at the University of Illinois have now revealed the naked truth about a classic bell-shaped curve used to describe the motion of a liquid as it diffuses through another material ('Brownian motion').

A team of Japanese scientists have developed a biodegradable nanosheet of only about 20 nanometers thickness that could replace surgical stitches and result in scar-free wound healing. In experiments they found that the sealing operation repaired the incision completely without scars and tissue adhesion. This approach would constitute an ideal candidate for an alternative to conventional suture/ligation procedures, from the perspective not only of a minimally invasive surgical technique but also reduction of operation times.