Articles from November 2011



Nanoparticles like a LEGO game

New processes that allow nanoparticles to assemble themselves into designer materials could solve some of today's technology challenges. Alex Travesset, Associate Professor at Iowa State University and the Ames Laboratory, writes in the Journal Science (Oct. 14 issue) that  the controlled self-assembly of nanoparticles could help researchers create new materials with unique electrical, optical, mechanical or transport properties

"Nanoparticle self-assembly has entered the LEGO era," Travesset said. "You can really work with nanoparticles in the same way you can work with LEGOs. This represents a breakthrough in the way we can manipulate matter. Really revolutionary applications will come".

Let's remind how Dr Ralph Merkle presents in his blog  the new nanotechnologies:

Manufactured products are made from atoms. The properties of those products depend on how those atoms are arranged.

If we rearrange the atoms in coal we can make diamond..

If we rearrange the atoms in sand (and add a few other trace elements) we can make computer chips.

If we rearrange the atoms in dirt,  water and air we can make potatoes..

Todays manufacturing methods are very crude at the molecular level. Casting, grinding, milling and even lithography move atoms in great thundering statistical herds. It's like trying to make things out of LEGO blocks with boxing gloves on your hands. Yes, you can push the LEGO blocks into great heaps and pile them up, but you can't really snap them together the way you'd like.

 

Transparent material ‘Best Invention of 2011’

Drs Ali Aliev, Yuri Gartstein and Ray Baughman, of the University of Texas at Dallas (UTD), have succeeded in producing what is technically referred to as the "mirage effect from thermally modulated transparent carbon nanotube sheets," or, as some in the popular press have termed it: an 'invisibility cloak'." The key to this breakthrough are carbon nanotubes—the successful result of another ongoing AFOSR-funded UTD program—that have the ability to disappear when rapidly heated. In reality, this effect is due to photothermal deflection, or a mirage effect, quite similar to what a driver may experience when a highway in the distance becomes so hot that a section of the road may look like a pool of water. This is due to the bending of the light around the hot road surface wherein the driver actually sees the reflected sky in place of the pavement. The carbon nanotubes create much the same effect when heated.

The Air Force Office of Scientific Research – ASFOR –, located in Arlington, Virginia, continues to expand the horizon of scientific knowledge through its leadership and management of the Air Force's basic research program. As a vital component of the Air Force Research Laboratory, AFOSR's mission is to discover, shape and champion basic science that profoundly impacts the future Air Force.
Transparent material breakthrough: One of Time magazine's 'Best Inventions of 2011'
Source: http://nanotech.utdallas.edu/personnel/staff/aliev.html

Nanowrinkles make smaller, more flexible electronic devices

Wrinkles and folds are ubiquitous. They occur in furrowed brows, planetary topology, the surface of the human brain, even the bottom of a gecko's foot. In many cases, they are nature's ingenious way of packing more surface area into a limited space. Scientists, mimicking nature, have long sought to manipulate surfaces to create wrinkles and folds to make smaller, more flexible electronic devices, fluid-carrying nanochannels or even printable cell phones and computers

"Wrinkles are everywhere in science," said Kyung-Suk Kim, professor of engineering at Brown University. "But they hold certain secrets. With this study, we have found mathematically how the wrinkle spacings of a thin sheet are determined on a largely deformed soft substrate and how the wrinkles evolve into regular folds."
Source; http://news.brown.edu/pressreleases/2011/11/wrinkles

A nano car with molecular 4-wheel drive

Scientists at the University of Groningen (Netherlands) and at Empa (Switzerland) have successfully taken “a decisive step on the road to artificial nano-scale transport systems”. They have synthesised a molecule from four rotating motor units, i.e. wheels, which can travel straight ahead in a controlled manner. “To do this, our car needs neither rails nor petrol; it runs on electricity. It must be the smallest electric car in the world – and it even comes with 4-wheel drive” comments Empa researcher Karl-Heinz Ernst. Reduced to the max: the emission-free, noiseless 4-wheel drive car, jointly developed by Empa researchers and their Dutch colleagues, represents lightweight construction at its most extreme. The nano car consists of just a single molecule and travels on four electrically-driven wheels in an almost straight line over a copper surface. The “prototype” can be admired on the cover of the latest edition of «Nature».

  

The downside: the small car, which measures approximately 4×2 nanometres – about one billion times smaller than a VW Golf – needs to be refuelled with electricity after every half revolution of the wheels – via the tip of a scanning tunnelling microscope (STM). Furthermore, due to their molecular design, the wheels can only turn in one direction. “In other words: there’s no reverse gear”, says Ernst, who is also a professor at the University of Zurich, laconically.
Source: http://www.empa.ch/plugin/template/empa/3/114118/—/l=2

Nanotechnology helps to produce plastics from bananas

The project led by Cidetec-IK4 scientists aims to develop plastics derived from waste organic material. This employment of raw materials from organic waste such as the banana plant, almond nut shells or crustacean shells has additional advantages, such as it does not influence the final price of foodstuffs and does not directly affect the environment. 

 

These new plastics, aimed at cleaner and more sustainable alternative to petroleum oil-derived ones, will have advanced properties using nanotechnology-based methods.
The Cidetec-IK4 technological centre, is based at the Donostia-San Sebastián Technological Park in Spain, and is a major European project for developing new plastics from organic waste.
Source: http://www.cidetec.es/noticias/03noticias_leer.php?id=297

Nanoparticles to improve cancer diagnostics

A Singapore research team led by Associate Professor Xiaogang Liu from  National University of Singapore’s (NUS) Department of Chemistry and its co-researchers from Saudi Arabia and China succeeded in developing an efficient upconversion process in nanoparticles, ensuring a broad tunability of light emission that could be used in imaging applications.

They found a chemical structure that can exhibit efficient upconversion properties through a special arrangement of energy levels. Their synthesis of lanthanide-doped core-shell nanocrystals which resulted in advanced optical properties that can control light, proved to be a novel approach, espacially potential application in cancer diagnostics, medical imaging and therapeutic delivery.
Source:  Nature Materials journal. Link: http://www.nature.com/nmat/journal/v10/n12/full/nmat3149.html

 

 

Promises and Perils in Nanomedecine

Ruth Duncan (Polymer Therapeutics Lab.Valencia, Spain) and Rogerio Gaspar (Faculty of Pharmacy of the University of Lisbon, Portugal) explain in a recent post to the American Chemical Association that nanomedicine — the application of nanotechnology to health care — often is overhyped as cure-alls or a potential danger. The concept debuted with the visionary notion that robots and electronic devices so tiny that dozens would fit across the width of a human hair could be built and put into the human body to treat disease and repair damaged organs. About 40 nano health care products actually are in use and nano-sized drugs, drug delivery devices, imaging agents, and other products are on the horizon.

But as well nanomedecine portends the release of dangerous nanoparticles, nanorobots or nanoelectronic devices that will wreak havoc in the body. In this review the two scientists just state where the knowledge of today can say about the future benefits and the dangers of nanomedicine.
Source: Ruth Duncan, Rogerio Gaspar. Nanomedicine(s) under the Microscope. Molecular Pharmaceutics, 2011. Link:    10.1021/mp200394t

Phone batteries ten times more powerful

 

A team of engineers from McCormick School of Engineering and Applied Science and  led by Professor Harold Kung, has created an electrode for lithium-ion batteries — rechargeable batteries such as those found in cellphones and iPods — that allows the batteries to hold a charge up to 10 times greater than current technology. Batteries with the new electrode also can charge 10 times faster than current batteries. “We have found a way to extend a new lithium-ion battery’s charge life by 10 times,” said Kung. 

The researchers combined two chemical engineering approaches to address two major battery limitations — energy capacity and charge rate — in one fell swoop. In addition to better batteries for cellphones and iPods, the technology could pave the way for more efficient, smaller batteries for electric cars. The technology could be seen in the marketplace in the next three to five years, the researchers said.

Source: Advanced Energy Materials.

 

Horticultural products cleaned by nanotechnologies

Around the world nanotechnology is taking off across a broad spectrum of industries and is changing the way we bring food from the farm to table. For horticultural products, the practice of manipulating material at an atomic level can replace chemical usage in cleaning. Agronomist Alberto Popper explains  what makes nanotechnology tick and how it is implemented. Popper, an agronomist with vast experience in the produce industry in Chile and abroad, has formed a portfolio of technological solutions for agribusiness.

Unlike traditional cleaning methods, where chemicals are applied that can be toxic or contaminating, nanotechnology usually has no or few residual effects in the control of microorganisms, bringing self-cleaning to the substrates and permanent biological control. This allows for significant savings in time, energy, labor and water in the washing and cleaning processes of agriculture, facilitating water flow and preventing the formation of salt and carcareous crust. The process also prevents corrosion and the accumulation of dirt.

Source: http://www.freshfruitportal.com/2011/11/14/nanotechnology-changing-the-face-of-chilean-horticulture/

Nanoparticule to treat coronary syndrome

A targeted, nanoparticle gelatin-based clot-busting treatment dissolved significantly more blood clots than a currently used drug in an animal study of acute coronary syndrome. The new drug-delivery system used gelatin to deactivate the clot-busting drug tissue plasminogen activator, or tPA, to treat acute coronary syndrome. Soundwaves were then used to reactivate tPA once it reached the blood clot. It is considered a stealth approach because tPA doesn’t act until it has reached its target.

When tPA is mixed with gelatin and administered in the form of nanoparticles, it reduces tPA activity. Inactivation of tPA during circulation is very important to reduce bleeding complications,” said Yoshihiko Saito, M.D., senior author and professor and cardiologist at Nara Medical University in Kashihara, Japan.
This gelatin-based drug-delivery system could potentially treat patients with
chest pain en route to the hospital via ambulance.
Source: American Heart Association’s Scientific Sessions 2011.

Nanomaterials for a new generation of boats

Zyvex Technologies announced today that it has launched a new division, in order to design and build the most advanced maritime platforms in the world. Zyvex Marine shipped this month its first production boat, a lightweight 54' vessel designed with the help of various nanotechnologies.

"Our production facility is closer to rocket science than traditional boat building," said Byron Nutley, Vice President and General Manager of Zyvex Marine. "We are the only company building boats out of nanomaterials. Zyvex Marine designs and builds the most advanced maritime platforms in the world."
Source: http://www.zyvextech.com/ 

Lithium-air battery ten times more powerful

Among various electrochemical energy storage systems explored to date, the lithium-air (Li-air) battery is one of the most promising technologies, with a theoretical energy density nearly ten times that of conventional lithium-ion batteries. This is because lithium metal as an anode has a capacity ten times higher than that of conventional graphite anodes, and oxygen as the cathode of a Li-air battery can be absorbed freely from the environment leading to a significant reduction in the weight and the cost of the battery.

 

Dr. Ji-Guang Zhang, a researcher at Pacific Northwest National Laboratory's – PNNL –Transformational Materials Science Initiative, and his team, demonstrate  in a recent post, that a novel air electrode consisting of an unusual hierarchical arrangement of functionalized graphene sheets (with no catalyst) delivers an exceptionally high capacity batteries – which is the highest value ever.
The performance of Li-air batteries is affected by many factors such as electrolyte composition, the macrostructure of the air electrode, and the micro- to nanostructure of carbonaceous materials.  This recent work by the PNNL team minimizes air-electrode-blocking problem and leads to significantly increased capacities.
Source: Nano Letters ("Hierarchically Porous Graphene as a Lithium-Air Battery Electrode")