Showing Spotlights 1433 - 1440 of 2428 in category All (newest first):
A problem with conventional photolithography techniques is that they cannot achieve the small size requirement of nanoholes and nanopillars, required for various nanofabrication applications, because of the wavelength limitation of the exposure light source. Other nanolithography techniques, such as electron-beam lithography, focused ion beam milling, and x-ray lithography, have the high resolution to form these nanoholes and nanopillars. However, these techniques are all very expensive or have too low a throughput to fabricate a large area of repetitive nanopatterns. A low cost nanosphere lithography method for patterning and generation of semiconductor nanostructures provides a potential alternative to conventional top-down fabrication techniques.
Aug 16th, 2010
Spin coating has been the dominant fabrication method for polymer electronics. However, it is not a high-throughput process and numerous research groups are trying to find a scalable fabrication method for polymer solar cells. One such method, spray coating, is capable of delivering large-area, uniform polymer thin films through a relatively simple process, while offering ample processing possibilities of engineering the film structure. Spray-coating is a high-rate, large-area deposition technique that ensures an ideal coating on a variety of surfaces with different morphologies and topographies. It is frequently used for industrial coating and in-line deposition processes. In spray-coating systems, the ink is atomized at the nozzle by pressure or ultrasound and then directed toward the substrate by a gas. An added advantage of spray-coating is that it is efficient: compared to other techniques only a small amount of the solutions are wasted.
Aug 13th, 2010
A new 290-page tome titled 'Strategic impact, no revolution' is the result of a year-long effort to study the strategic value and impact of NMP in its wider European and international context, with special focus on the ERA dimension, against the general policy objectives of FP6 and against the specific objectives of NMP. The title of this report refers to the general finding that the third thematic priority in FP6 strategically affected Europe's competitive position and was an important programme which also influenced Member States' policies and research agendas. However, it cannot be directly linked to a revolution with regard to creating substantial scientific or industrial breakthroughs although these were among the explicitly targeted objectives. The program strengthened Europe's position as one of the world leaders in the respective scientific and industrial fields, but did not enable Europe to outperform other key actors such as the United States or Japan.
Aug 12th, 2010
Delivering healthy proteins directly into human cells to replace malfunctioning proteins is considered one of the most direct and safe approaches for treating diseases. Controlled and long-term protein drug delivery has also been considered as one of the most promising biomedical applications of nanotechnology. So far, though, the effectiveness of protein therapy has been limited by low delivery efficiency and the poor stability of proteins, which are frequently broken down and digested by cells' protease enzymes before they reach their intended target. This not only makes the drugs ineffective, it can also cause unpredictable side effects such as inflammation, toxicity, and immune responses. The best way for the delivery of protein drugs without denaturation might be possible by exploiting the passive diffusion through a membrane without physical and chemical stresses. This can be achieved when pore sizes in a membrane are controlled to satisfy the single-file diffusion condition of protein drugs.
Aug 10th, 2010
With fully conclusive findings about the toxicity of carbon nanotubes (CNTs) still up in the air, research on biomedical applications of CNTs is pushing full steam ahead. Adding to the list of potential concerns, a recent nanotoxicology study by a U.S.-Chinese research team looked into the impact of carbon nanotubes on male reproductive health. The translocation and biodistribution of nanoparticles are key factors in their toxicity evaluation in vivo. Although other nanoparticles such as gold and magnetic nanoparticles have been reported to enter testes in small quantities, it had not been established whether CNTs could enter or accumulate in the testis. This pilot study investigated the effects of intravenous injection of single and multiple doses of water-soluble multiwalled carbon nanotubes on the reproductive systems of male mice.
Aug 9th, 2010
Bullet-proof vests are basically made from high stiffness and toughness, woven or laminated, polymeric fibers stacked in a number of layers. Upon impact of the striking bullet, the fabric material absorbs the energy by stretching of the fibers and the stiff fibers ensure that the load is dispersed over a large area throughout the material. Carbon nanotube is an ideal candidate material for bulletproof vests due to its unique combination of exceptionally high elastic modulus and high yield strain. If one compares these values with those for other fibers suitable for ballistic applications, the enormous potential of CNTs as a candidate material for bullet-proof armor system is quite evident.
Aug 6th, 2010
Solar cells that convert sunlight to electric power traditionally have been dominated by solid state junction devices, often made of silicon wafers. Thanks to nanotechnology, this silicon-based production technology has been challenged by the development of a new generation of solar cells based on thin film materials, nanocrystalline materials and conducting polymeric films. These offer the prospects of cheaper materials, higher efficiency and flexible features. Thanks to a highly efficient polymer solar cell fabrication method by a novel coating process - roller painting - even the mass production of polymer solar cells is now within reach. A particular advantage of roller painting compared to other coating processes is ease of control of the film thickness and uniformity.
Aug 4th, 2010
Sophisticated molecular-size motors have evolved in nature, where they are used in virtually every important biological process. Some fascinating examples in nature are DNA and RNA polymerase, rotary motors such as ATP synthase, and flagella motors. In contrast, the development of synthetic nanomotors that mimic the function of these amazing natural systems and could be used in man-made nanodevices is in its infancy. Nevertheless, scientists are making good progress in achieving cargo transport by artificial nanomachines although often these advances are handicapped by several drawbacks. Researchers in Germany have now demonstrated the directed loading and transport of microobjects by high propulsion powered tubular microbots driven by a microbubble propulsion mechanism.
Aug 3rd, 2010