A thin layer of graphene paint can make impermeable and chemically resistant coatings which could be used for packaging to keep food fresh for longer and protect metal structures against corrosion, new findings from The University of Manchester show.
Nanotechnology - Technology for every facet of life
Friday, September 12, 2014
Friday, September 5, 2014
Monday, August 4, 2014
Chemists create nanofibers using unprecedented new method, reminiscent of fibers found in living cells
Researchers from Carnegie Mellon University have developed a novel method for creating self-assembled protein/polymer nanostructures that are reminiscent of fibers found in living cells. The work offers a promising new way to fabricate materials for drug delivery and tissue engineering applications. The findings were published in the July 28 issue of Angewandte Chemie International Edition.
Saturday, August 2, 2014
"Pistachio Shell Used in Production of Wood Plastic Nanocomposite"
The nanocomposite can be used in building
industry, and it is resistant to humidity, loss of color and various
types of fungi and insects.
In this research, the powder of pistachio shell was used as the filler of heavy polyethylenematrix. In addition, the effect of the presence of nano clay (cloisite 20A) and optical stabilizers was studied on tensile properties, impact, loss of color and resistance to weathering of the produced plastic wood composite.
Iran has always been among the top producers of pistachio in the world, and it annually produces and exports thousands of tons of pistachio to other countries. Therefore, it is very easy to have access to pistachio shell in the country as agricultural waste. On the other hand, the structure of pistachio shell and its components, specifically cellulose, make this material an appropriate choice for the production of composites. Pistachio shell contains cellulose, hemicelluloses and lignin.
The greatest advantage of plastic wood composite is its very good compatibility with the environment. This material is made of useless pieces of wood and recyclable plastic materials, and it has less maintenance cost in comparison with rough wood. It also has high resistance against decay, fungi and insects.
Based on the obtained results, the best increase in tensile strength and tensile module takes place when three weight sections of nanoparticles are used. When the amount increases to six, the opposite result is achieved. Tensile strength increases 27% when the amount of nanoclay increases from zero to three weight sections, while it decreases 4% when the concentration reaches six weight sections.
In this research, the powder of pistachio shell was used as the filler of heavy polyethylenematrix. In addition, the effect of the presence of nano clay (cloisite 20A) and optical stabilizers was studied on tensile properties, impact, loss of color and resistance to weathering of the produced plastic wood composite.
Iran has always been among the top producers of pistachio in the world, and it annually produces and exports thousands of tons of pistachio to other countries. Therefore, it is very easy to have access to pistachio shell in the country as agricultural waste. On the other hand, the structure of pistachio shell and its components, specifically cellulose, make this material an appropriate choice for the production of composites. Pistachio shell contains cellulose, hemicelluloses and lignin.
The greatest advantage of plastic wood composite is its very good compatibility with the environment. This material is made of useless pieces of wood and recyclable plastic materials, and it has less maintenance cost in comparison with rough wood. It also has high resistance against decay, fungi and insects.
Based on the obtained results, the best increase in tensile strength and tensile module takes place when three weight sections of nanoparticles are used. When the amount increases to six, the opposite result is achieved. Tensile strength increases 27% when the amount of nanoclay increases from zero to three weight sections, while it decreases 4% when the concentration reaches six weight sections.
Friday, August 1, 2014
"Scientists Develop Force Sensor from Carbon Nanotubes"
The scientists proposed using two nanotubes, one of which is a long cylinder with double walls one atom thick. These tubes are placed so that their open ends are opposite to each other. Voltage is then applied to
them, and a current of about 10nAflows through the circuit.
Carbon tube walls are good conductors, and along the gap between the ends of the nanotubes the current flows thanks to the tunnel effect, which is a quantum phenomenon where electrons pass through a barrier that is considered insurmountable in classical mechanics.
This current is called tunneling current and is widely used in practice. There are, for example, tunnel diodes, wherein current flows through the potential barrier of the p-n junction.
Another example is a scanning tunneling microscope (STM), in which the surface of a sample is scanned with a very sharp needle under voltage. The needle slides along the surface, and the magnitude of the current flowing through it shows the distance to the sample with such accuracy that the STM can detect protrusions one atom high.
The authors of the article used the relationship between the tunneling current and the distance between the ends of the nanotubes to determine the relative position of the carbon nanotubes and thus to find the magnitude of the external force exerted on them.
The new sensor allows the position of coaxial cylinders in two-layer nanotubes to be controlled quite accurately. As a result, it is possible to determine the stretch of an n-scale object, to which electrodes are attached. Calculations made by the researchers showed the possibility of recording forces of a few tenths of a nN(10-10newtons). To make it clearer, a single bacterium weighs about 10-14newtons on average, and a mosquito weighs a few dozen mcN (10-5 N).However, the device developed by the physicists may find application beyond micro scales.
A double-layered coaxial nanotube is akin to a microscopic cylinder with a sliding piston. Such a system has already been considered by a number of other researchers as a potential part for various types of nanomachines. Nanotubes have been proposed for the role of micromanipulators, or connecting "studs" for complex mechanisms, and they may even be used for data storage; the position of the inner "piston" may encode one bit of information or more.
Furthermore, calculations have shown that it is possible to create a combined device, where inside a two-layer carbon nanotube there will be magnetic fullerenes. When placed in a magnetic field, a power will emerge, which could be measured by changes in the magnitude of tunneling current. This will convert the force sensor into a magnetic field sensor.
"Scientists Develop Force Sensor from Carbon Nanotubes"
Thursday, July 31, 2014
"Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer"
One pioneering approach, discussed in a review article published this week in WIREs Nanomedicine and Nanobiotechnology, uses nanoparticles to jumpstart the body's ability to fight tumors. Nanoparticles are too small to imagine. One billion could fit on the head of a pin. This makes them stealthy enough to penetrate cancer cells with therapeutic agents such as antibodies, drugs, vaccine type viruses, or even metallic particles.
Though small, nanoparticles can pack large payloads of a variety of agents that have different effects that activate and strengthen the body's immune system response against tumors.
There is an expanding array of nanoparticle types being developed and tested for cancer therapy. They are primarily being used to package and deliver the current generation of cancer cell killing drugs and progress is being made in that effort.
"Our lab's approach differs from most in that we use nanoparticles to stimulate the immune system to attack tumors and there are a variety of potential ways that can be done," said Steve Fiering, PhD, Norris Cotton Cancer Center researcher and professor of Microbiology and Immunology, and of Genetics at the Geisel School of Medicine at Dartmouth. "Perhaps the most exciting potential of nanoparticles is that although very small, they can combine multiple therapeutic agents."
The immune therapy methods limit a tumor's ability to trick the immune system. It helps it to recognize the threat and equip it to effectively attack the tumor with more "soldier" cells. These approaches are still early in development in the laboratory or clinical trials.
"Now that efforts to stimulate anti-tumor immune responses are moving from the lab to the clinic, the potential for nanoparticles to be utilized to improve an immune-based therapy approach is attracting a lot of attention from both scientists and clinicians. And clinical usage does not appear too distant," said Fiering.
Fiering is testing the use of heat in combination with nanoparticles. An inactive metallic nanoparticle containing iron, silver, or gold is absorbed by a cancer cell. Then the nanoparticle is activated using magnetic energy, infrared light, or radio waves. The interaction creates heat that kills cancer cells. The heat, when precisely applied, can prompt the immune system to kill cancer cells that have not been heated. The key to this approach is minimizing healthy tissue damage while maximizing cancerous tumor destruction of the sort that improves recognition of the tumor by the immune system
Nanotechnology Now - Press Release: "Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer"Though small, nanoparticles can pack large payloads of a variety of agents that have different effects that activate and strengthen the body's immune system response against tumors.
There is an expanding array of nanoparticle types being developed and tested for cancer therapy. They are primarily being used to package and deliver the current generation of cancer cell killing drugs and progress is being made in that effort.
"Our lab's approach differs from most in that we use nanoparticles to stimulate the immune system to attack tumors and there are a variety of potential ways that can be done," said Steve Fiering, PhD, Norris Cotton Cancer Center researcher and professor of Microbiology and Immunology, and of Genetics at the Geisel School of Medicine at Dartmouth. "Perhaps the most exciting potential of nanoparticles is that although very small, they can combine multiple therapeutic agents."
The immune therapy methods limit a tumor's ability to trick the immune system. It helps it to recognize the threat and equip it to effectively attack the tumor with more "soldier" cells. These approaches are still early in development in the laboratory or clinical trials.
"Now that efforts to stimulate anti-tumor immune responses are moving from the lab to the clinic, the potential for nanoparticles to be utilized to improve an immune-based therapy approach is attracting a lot of attention from both scientists and clinicians. And clinical usage does not appear too distant," said Fiering.
Fiering is testing the use of heat in combination with nanoparticles. An inactive metallic nanoparticle containing iron, silver, or gold is absorbed by a cancer cell. Then the nanoparticle is activated using magnetic energy, infrared light, or radio waves. The interaction creates heat that kills cancer cells. The heat, when precisely applied, can prompt the immune system to kill cancer cells that have not been heated. The key to this approach is minimizing healthy tissue damage while maximizing cancerous tumor destruction of the sort that improves recognition of the tumor by the immune system
Wednesday, July 30, 2014
Nanotechnology Now - Press Release: "Nano-supercapacitors for electric cars"
Electric cars are very much welcomed in Norway and they are a common sight on the roads of the Scandinavian country - so much so that electric cars topped the list of new vehicle registrations for the second time. This poses a stark contrast to the situation in Germany, where electric vehicles claim only a small portion of the market. Of the 43 million cars on the roads in Germany, only a mere 8000 are electric powered. The main factors discouraging motorists in Germany from switching to electric vehicles are the high investments cost, their short driving ranges and the lack of charging stations. Another major obstacle en route to the mass acceptance of electric cars is the charging time involved. The minutes involved in refueling conventional cars are so many folds shorter that it makes the situation almost incomparable. However, the charging durations could be dramatically shortened with the inclusion of supercapacitors. These alternative energy storage devices are fast charging and can therefore better support the use of economical energy in electric cars. Taking traditional gasoline-powered vehicles for instance, the action of
braking converts the kinetic energy into heat which is dissipated and unused. Per contra, generators on electric vehicles are able to tap into the kinetic energy by converting it into electricity for further usage. This electricity often comes in jolts and requires storage devices that can withstand high amount of energy input within a short period of time. In this example, supercapacitors with their capability in capturing and storing this converted energy in an instant fits in the picture wholly. Unlike batteries that offer limited charging/discharging rates, supercapacitors require only seconds to charge and can feed the electric power back into the air-
braking converts the kinetic energy into heat which is dissipated and unused. Per contra, generators on electric vehicles are able to tap into the kinetic energy by converting it into electricity for further usage. This electricity often comes in jolts and requires storage devices that can withstand high amount of energy input within a short period of time. In this example, supercapacitors with their capability in capturing and storing this converted energy in an instant fits in the picture wholly. Unlike batteries that offer limited charging/discharging rates, supercapacitors require only seconds to charge and can feed the electric power back into the air-
Rapid energy storage devices are distinguished by their energy and power density characteristics - in other words, the amount of electrical energy the device can deliver with respect to its mass and within a given period of time. Supercapacitors are known to possess high power density, whereby large amounts of electrical energy can be provided or captured within short durations, albeit at a short-coming of low energy density. The amount of energy in which supercapacitors are able to store is generally about 10% that of electrochemical batteries (when the two devices of same weight are being compared). This is precisely where the challenge lies and what the "ElectroGraph" project is attempting to address. ElectroGraph is a project supported by the EU and its consortium consists of ten partners from both research institutes and industries. One of the main tasks of this project is to develop new types of supercapacitors with significantly improved energy storage capacities. As the project is approaches its closing phase in June, the project coordinator at Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Stuttgart, Carsten Glanz explained the concept and approach taken en route to its successful conclusion: "during the storage process, the electrical energy is stored as charged particles attached on the electrode material." "So to store more energy efficiently, we designed light weight electrodes with larger, usable surfaces."
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