Nano On Mars
27 June 2008, 11:00
Categories: optics--photonics
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Ian Birkby recently spoke to Ola Modinger of Nanosurf about nanotechnology in space. NASA has rocketed an AFM (Atomic Force Microscope), designed by Nanosurf, across the solar system and has placed it on the surface of Mars in the search for extra terrestrial life.
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Harnessing Materials for Energy
27 June 2008, 10:56
Categories: energy
The MRS bulletin Harnessing Materials for Energy focuses on the most important materials research challenges that need to be addressed to move toward secure, affordable, and environmentally sustainable energy, to meet the world’s accelerating energy needs. The issue follows the full energy chain including production, storage, distribution, use, and efficiency. The articles are designed to present an objective and global view of the energy challenges within each energy sector and the promising transformational materials research directions for meeting these challenges as far into the future as is scientifically feasible to consider (targeting 10-, 25-, and 50-year outlooks). The issue was launched at the 2008 MRS Spring Meeting with an Energy Forum featuring presentations by leading experts in the field.
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Disruptive Technologies
27 June 2008, 10:54
Categories: other
The National Intelligence Council (NIC) is interested in disruptive technologies that have the potential to cause a noticeable, even if temporary, degradation or enhancement in one of the elements of US national power (geopolitical, military, economic, or social cohesion). According to the NIC, the six disruptive technologies most likely to enhance or degrade US national power in 2025 are in the areas of: Biogerontechnology; Energy Storage Materials; Biofuels and Bio-Based Chemicals; Clean Coal Technologies; Service Robotics; and the Internet of Things. Nanotechnology cuts across all of these.
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NanoTweezers Trap Objects
26 June 2008, 13:00
Categories: tools optics--photonics
Using laser light, researchers at the University of Manchester have made the first nano-optical tweezers that can trap and move objects on the nanoscale. The devices, which are based on “nanopillars”, offer many advantages over traditional optical tweezers; the new devices have a much bigger trapping force and provide significantly smaller trapping volumes for much less laser power than employed in conventional optical tweezers. The secret behind the new device is that it exploits “virtual” photons. The breakthrough result opens the way to manipulating fragile biological cells and making structures from nanoscale building blocks.
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Light Drives Mechanical Work
26 June 2008, 12:48
Categories: smt-polymorphic-shape-shifters smart-materials-smt
Smart materials that change shape in response to external stimuli form the basis of modern devices, and, in turn, have recently stimulated the imagination of many designers. But identifying materials that convert an input stimulus to mechanical work has been of long standing interest. There are some outstanding examples: the description of the pyroelectric effect in tourmaline by Theophrastus in 314 BC; the observation of piezoelectricity by Pierre and Jacques Curie in 1880; and the development of the bimetallic strip by John Harrison in the 1700s to measure nautical time.
Recently, researchers have shown a growing interest in the use of light (photons from lasers) as the energy input for stimulating materials. In the conversion of light to mechanical work, photons are emitted by a light source and are absorbed by a photoactive material that may produce mechanical motion, either by: (a) a reversible conformational change, or (b) a local temperature increase. When these molecular processes are amplified to macroscopic shape or volume changes, mechanical work or motion can be integrated into a range of remotely controlled devices, such as beam stirring mirrors or robots.
One of the first realizations of this idea was by Uchino in 1989, who demonstrated photostriction of PLZT (lanthanum modified lead zirconate titanate) with the intent to drive robots remotely in a non-contact, wireless mode. In contrast to thermal, electrical, or chemical approaches, a coherent and wavelength-specific photon flux enables facile ‘remote’ control of the process, as well as precise spatial localization.
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Polymers On The Move
26 June 2008, 12:12
Categories: molecular-machines--devices smt-polymorphic-shape-shifters
What is it about nanobots that captures our imagination? We are all nostalgic for the films we watched as young children, but some scientists go a step further: they take a good idea that was once considered to be science fiction and try to turn it into a reality. Two such visionaries are Anthony Ryan and Richard Jones from the University of Sheffield in the UK. In the current issue of Materials Today they discuss how their work on polymers has brought them a step closer to making a small machine that is capable of moving round the body.
In the same issue, Wilhelm T.S. Huck, from University of Cambridge, discusses how the drive for miniaturization has resulted in a number of artifical nano- and micron-scale actuators that use responsive polymers. Some of their characteristics are based on examples in nature, where a wide range of molecular motors provide locomotion at the nano- and micron-scale. In his review, several designs based on polymer gels and brush films are highlighted. Gels are well-established materials with proven ability to actuate at macroscopic lengthscales using a wide range of external stimuli. Polymer brushes are emerging as another promising set-up for creating responsive surfaces that can transduce chemical or physical stimuli into mechanical stresses. The advantages of polymer brushes are the level of control that can be achieved over the thickness of the polymer film, as well as the wide range of possible chemical functionalities that can be introduced into the brushes.
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Transparent Nanotubes Improve Solar Cells
26 June 2008, 11:57
Categories: smt-energy-photovoltaic nanotubes-wires-fullerenes
Nanotechnology is paving the way toward improved solar cells, particularly third generation solar cells. New research shows that a film of carbon nanotubes may be able to replace two of the layers normally used in a solar cell, with improved performance at a lower cost. Researchers have found a surprising way to give the nanotubes the properties they need: add defects.
Currently, dye-sensitized solar cells have a transparent film made of an oxide that is applied to glass and conducts electricity. In addition, a separate film made of platinum acts as a catalyst to speed the chemical reactions involved. Both of these materials have disadvantages. The oxide films can’t easily be applied to flexible materials; they perform much better on a rigid and heat resistant substrate like glass. This increases costs and limits the kinds of products that can be made. Additionally, expensive equipment is necessary to create the platinum films for solar cells.
Jessika Trancik of the Santa Fe Institute, Scott Calabrese Barton of Michigan State University and James Hone of Columbia University decided to use carbon nanotubes to create a single layer that could perform the functions of both the oxide and platinum layers. They needed it to have three properties: transparency, conductivity, and catalytic activity.
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Functional Surfaces Enable Nanocubes To Self-Assemble
26 June 2008, 11:08
Categories: self-assembly
A recent paper by researchers at Washington University in St. Louis and the University of Washington in Seattle, details a general method for modifying cubic building blocks with nanoscale dimensions. The study suggests that the surfaces of the blocks can be modified to enable the controlled self-assembly of nanostructures and systems.
“While the use of hydrophobic and hydrophilic self-assembled monolayers (SAM) in self-assembly processes are known, our example is notable in the way we programmed the components and used both hydrophobic and capillary interactions for assembly,” explains Dr. Younan Xia, lead researcher. “This gave us the control to assemble structures with different geometries and sizes. Furthermore, the scale and the extent of the assembly were unusual as we could assemble 100 nm cubes into a three-dimensional cubic array over micron distances, which is something not demonstrated previously.”
Dr. Xia points out that the key concept of self-assembly is that the final structure is usually predetermined by the characteristics of the building blocks: the information that defines a self-assembly process – and thus the final structure – is often coded in the building blocks in the form of shape, topology, or surface functionality. From the possible combinations of hydrophobic and hydrophilic faces, Xia’s team generated five distinct SAM-modified silver nanocubes and assembled them into four different nanostructures and one microstructure.
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Molecular Robots Explore Cells
26 June 2008, 10:49
Categories: molecular-machines--devices
Molecular “robots” have been developed by researchers to explore the chemical environments of living cells and transmit back the results. The new molecules encrypt measurements of two different chemical features of cell membranes into light signals to be decoded by the researchers, an international group from Queen’s University, Belfast, and the University of Tokyo. One measurement is encoded in the light’s intensity, and the other in its wavelength, or color.
“Concepts of nanorobotic vehicles and of mapping out nanospaces have emerged from science fiction into experimental science for the first time,” said lead researcher A. Prasanna de Silva of Queen’s University.
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Nanoparticles Assemble To Encase Oil Drops
26 June 2008, 10:29
Categories: nanoparticles nanotubes-wires-fullerenes
In a development that could lead to new technologies for cleaning up oil spills and polluted groundwater, scientists at Rice University and Rensselaer Polytechnic Institute have shown how tiny, stick-shaped particles of metal and carbon can trap oil droplets in water by spontaneously assembling into bag-like sacs.
The tiny particles were found to assemble spontaneously by the tens of millions into spherical sacs as large as BB pellets around droplets of oil in water. In addition, the scientists found that ultraviolet light and magnetic fields could be used to flip the nanoparticles, causing the bags to instantly turn inside out and release their cargo—a feature that could ultimately be handy for delivering drugs.
“The core of the nanotechnology revolution lies in designing inorganic nanoparticles that can self-assemble into larger structures like a ‘smart dust’ that performs different functions in the world – for example, cleaning up pollution,” said lead researcher Pulickel Ajayan. “Our approach brings the concept of self-assembling, functional nanomaterials one step closer to reality.”
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Nano Vent-Skin
26 June 2008, 00:23
Categories: designers energy
Nano Vent-Skin (NVS) is a project that aims to trigger new approaches to greener, more energy efficient structures. Conceived by Agustin Otegui, a designer in London, the NVS system consists of micro-scale wind turbines that are integrated into buildings and other structures to generate electricity.
There are three main aspects to the NVS systems, which involve interactions with sunlight, wind, and carbon dioxide. The outer surface of the structure absorbs sunlight through an organic photovoltaic skin and transfers electricity through nano-wires to storage units at the end of each panel. Small wind turbines on the panel are also used to generate electricity, and the inner skin of each turbine absorbs CO2 as wind passes through it.
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A Flagellum in Neutral
22 June 2008, 15:37
Categories: molecular-machines--devices biomimicry
It has been long been known that bacteria swim by rotating their tail-like structure called the flagellum. Now, a paper by researchers at the University of Indiana and Harvard University describes how the flagellum’s rotations are stopped so that bacteria stop moving. While a bacterium is swimming, it releases a protein that flows between its gear and molecular engine, detaching the gear and thereby stops the delivery of power to its flagellum.
This improved understanding of how flagella work may give nanotechnologists ideas about how to regulate tiny engines of their own creation. The flagellum is one of nature’s smallest and most powerful motors. The flagellum of some bacteria can, for example, rotate more than 200 times per second.
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Luminescent Polymer Explosives Detector
19 June 2008, 06:01
Categories: smt-luminescent-light-emit sensors
A new, easy-to-use explosives detector developed by RedXDefense could provide a quick, simple visual diagnostic for plastic explosives. The device is portable and designed for use by non-scientists at security checkpoints and under harsh conditions. The product, called the XPak, is currently undergoing field tests in Iraq.
“Most explosives-detection methods go after sensing vapors,” says William Trogler, a chemistry professor at the University of California, San Diego, who developed the technology behind the device. This works well for detecting buried land mines and other devices that use volatile explosives, such as TNT, that form a gas that can be detected in the air. But the plastic explosives often used by terrorists are not very volatile, and technologies for their detection usually require dislodging the explosive from a surface, such as with a puff of air, before running a chemical analysis. And these systems are not portable.
Trogler developed a sprayable polymer that fluoresces blue-green under ultraviolet (UV) light, unless in the presence of explosive molecules, including PETN and TNT, that turn off this fluorescence. When the polymer is sprayed on a surface and examined under UV light, explosives appear as black spots.
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Nanotube Super-Bridges
19 June 2008, 05:04
Categories: nanotubes-wires-fullerenes
Carbon nanotube bundles could be used to extend the main span of suspension bridges by up to three times, according to new work by researchers in Italy. Nicola Pugno and Alberto Carpinteri of Turin Polytechnic have calculated that the main span of the Messina bridge could be increased to more than 6 km from a possible 2 km today. The result might also allow “superbridges” to be built in the future at reduced cost, say the researchers.
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NanoSoccer
18 June 2008, 11:15
Categories: NEMS--MEMS molecular-machines--devices
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If you love soccer but don’t want to wait until the next World Cup to satisfy your appetite for the most popular game on Earth, the National Institute of Standards and Technology (NIST) has the answer—though the nourishment comes in very small bites.
Nanosoccer — the Lilliputian competition where computer-driven nanobots the size of dust mites challenge one another on fields no bigger than a grain of rice — will celebrate its first birthday this summer, and NIST is marking the anniversary with a new web site. Highlighting the site is a link to the recently produced video, “Bend It Like NIST: Tiny Soccer Players Pave Way for Microbots,” a two-minute program that demonstrates how nanosoccer tests agility, maneuverability, response to computer control, and the ability to move objects—all skills that future miniaturized robot workers will need for tasks such as microsurgery within the human body or the manufacturing of atom-sized components for microscopic electronic devices.
The soccer nanobots are operated by remote control under an optical microscope. They move in response to changing magnetic fields or electrical signals transmitted across the microchip arena. Although the bots are a few tens of micrometers to a few hundred micrometers long, they are considered “nanoscale” because their masses range from a few nanograms to a few hundred nanograms. They are manufactured from materials such as aluminum, nickel, gold, silicon and chromium.
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Solar Cells Spiked With Nanowires
18 June 2008, 10:57
Categories: nanotubes-wires-fullerenes smt-energy-photovoltaic
University of California, San Diego electrical engineers have created experimental solar cells spiked with nanowires. The indium phosphide nanowires were grown directly on an electrode, greatly increasing the flow of electrons through a polymer film to the electrode. Although still at the proof of concept stage, this nanotech innovation could ultimately lead to more efficient thin-film solar cells.
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Green Nano For Construction
18 June 2008, 10:57
Categories: other
How green nanotechnology enables sustainable construction, is the theme of an upcoming one-day workshop in Copenhagen. The workshop will take place on September 25th in connection with the 2008 Nanotech Northern Europe Conference (NTNE), the largest annual nanotech conference in Europe. The event is a unique opportunity to bring together nanoscientists and different stakeholders from the construction sector to discuss technology developments and find potential applications and new business solutions.
The workshop features a series of selected presentations from the perspective of businesses and science, covering a wide variety of topics such as smart windows, green cement, self-cleaning materials, high-performance insulation materials, solutions for indoor climate, health and risk related issues, and more.
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The Science of Probability or Exactability
18 June 2008, 10:46
Categories: scientists quantum-mechanics
Traditional, scholarly scientific theory which revolves around Albert Einstein and his assertion that “God does not play dice with the universe,” or the probability concept taught by academic institutions, is certainly improbably wrong, affirms New Quantum Mechanics Foundation founder Kwaku Boateng.
For centuries, the study of the behaviors of microscopic particles using the science of mathematics has attempted to explain the foundation of all existence, all the while being only able to investigate properties of the tiniest of building blocks indirectly such as with readings across the visual spectrum. Purports Boateng, any examination in science falls flat without Erwin Schrodinger, a colleague of Einstein’s, and acceptance of Schrodinger’s wave equation.
According to Boateng, understanding the universe involves expanding the concept of dimensions and waving goodbye to the common Big Bang theory. Scientific enlightenment involves embracing a mathematically sound atomic theory which accurately predicts movement of electrons in an atom without probability, which can be visualized according to Schrodinger’s description. Boateng contends established, sanctioned education goes too far in simplifying reality by teaching a mathematical description of nature based on the original architects of quantum mechanics, when inner atomic orbits really consist of highly complex and variable configurations.
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Self-Regulating Photoprotection
18 June 2008, 10:11
Categories: molecular-machines--devices biomimicry
Arizona State University chemists have demonstrated a nanotech version of molecular self-regulation. The ASU researchers have designed a molecule that mimics the way in which plants defend themselves from an overload of sunshine, by draining away the excess light energy as heat so that it can not generate destructive high energy intermediates. The nanotech molecule is composed of five components, one of which responds to light by reversibly changing shape.
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Janus Particles Make Zippers For Membranes
18 June 2008, 10:02
Categories: membranes nanoparticles
Nanotech researchers have appropriated the name of Janus – the Roman god of gates and doorways, usually depicted with two heads looking in opposite directions – to name a class of particles that consist of two hemispheres that are fused together. The amphiphilic particles, otherwise known as Janus particles, contain both hydrophobic and hydrophilic regions, as each of the two hemispheres is made from a different substance.
Their particular structure makes Janus particles an intriguing subject for exploring new applications for their novel properties. University of Pittsburgh researchers have now isolated a means of using them to make ‘re-sealable’ pores in lipid bilayer membranes. The localization of the nanoparticles in the pore can be thought of as the placement of a zipper, which allows a specific slit to be opened or closed at will.
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