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UC Santa Barbara researchers (see story below) were able to link Einstein’s general theory of relativity to a totally different area of physics and hope the tools will one day shed light on new types of superconductors. Credit: Jorge Santos.

Check ‘em out:

How to outshine a quantum dot using inorganic silica shields to prevent photobleaching of organic dyes

Unusual strategies for using indium gallium nitride grown on silicon (111) for solid-state lighting

Superconductivity, Einstein team up

Penn engineers: Two-dimensional graphene metamaterials and one-atom-thick optical devices

With a new printing technique, researchers can now make enough metamaterials to begin fabricating invisibility cloaks and superlenses

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R50 vacuum insulation panel, 30×48x1 inch. Credit: ThermalVisions.

Nano R&D is opening up new energy-conservation vistas, but a new report from Lux Research claims that the adoption of existing nano-enabled products, such as aerogels, low-friction coatings and quantum dot LEDs, could yield a huge energy-consumption reduction in three countries representative of nations with developed economies: Japan, Germany and the United States.

How huge? Lux, which provides strategic advice and intelligence on emerging technologies, says that these nano products could cut energy consumption by 12%. No one is advocating this (settle down Ohio and West Virginia), but Lux says that is the equivalent of shutting down all of the coal-powered generation plants in the U.S.

Lux researcher and lead author of the report David Hwang says researchers examined energy usage in residential, commercial, industrial and transportation sectors, and then interviewed nanotech product developers, manufacturers and end users. Generally speaking, they discovered that the U.S. would benefit most from nano in the automobile sector, Germany from heating application for residential and commercial use and Japan from lighting applications. Here is how Lux summarized its observations:

• “The ubiquitous American automobile drives most energy consumption in the U.S. Hence, low-friction tribological coatings and lightweight nanocomposites offer the biggest opportunities — 1.8% and 3.6%, respectively — for reducing energy consumption. With 3.9% total energy spent on lighting in the commercial, industrial, and residential sectors, QD-enabled LED lighting could cut another 2.5% from the U.S.’s energy consumption in 2020.”

• “Germany’s energy consumption is dominated by space heating. In 2009, 28.9% of the country’s total consumption went to heating living and work spaces in the residential and commercial sectors. Consequently, nano-enabled insulation could help lower countrywide consumption by 6.8%, representing almost half of Germany’s total potential savings. Adoption of tribological coatings and nanocomposites in German automobiles could cut another 3.8% from the country’s total consumption by 2020.

• “In 2009, 4.6% of Japan’s energy was used for general space illumination. With the large efficiency increases that QD-enabled LEDs deliver, the country could shave off 3.3% of total consumption by 2020.”

Hwang says the reference to nano-enabled insulation includes things such as aerogels, vacuum insulated panels with aerogel and other foam cores, polyurethane foams and coated glasses, although he says that coated glass, thermochromic glass, etc., will play a bigger role in locales where cooling is more important than heating. He mentions that Cabot and Aspen are finding significant sales success in the European insulation market.

In addition, he notes predicts that ceramic materials can play a big role in energy savings in the automotive composites field.

Regarding QD-enabled LEDs makers, Hwang says that joint efforts in the field, for example between Nexxus Lighting and QD Vision, NN Labs and Renaissance, and Nanosys and Samsung.

Nexxus/QD Vision introduced the first commercial LED lamp line that uses QDs in May 2009, and actually started to ship the bulbs in March 2010. The allure of QDs is that it improves the color quality and warms LED light, thereby avoiding some of the pitfalls that have limited the acceptance of CFL bulbs. The Nexxus/QD Vision approach is to apply a thin film of QD to the external face of LEDs. The companies say their “Array Quantum LED” bulbs are six times more efficient than incandescent ones. They aren’t cheap, with some online suppliers selling them for $100+ per bulb.

NN Lab’s angle is that it’s QDs are made from indium phosphide. It describes this as an environment-friendly alternative to the typical cadmium selenide-based QDs, developed in collaboration with the University of Arkansas. NNCrystal, a wholly owned subsidiary of Hangzhou Najing Technology Co., has licensed NN Lab’s Qshift Lucid and Coral technologies and is working with Renaissance Lighting to introduce a line of Solia-branded lighting products. This is also a coating-on-LED approach.

Hwang says that the 12% cut in energy use is an extremely optimistic number based on a 10-year model. He cautions that 1.6% is a more realistic energy decrease, but says several external factors, such as government policy and the price of oil, can significantly influence the adoption of these technologies. He also says the five-year cycle for automotive development will introduce a lag between adoption of a technology and a product hitting that marketplace.

Hwang also tells me that they chose the three countries because they were good proxies for developed economies in the Americas, Europe in Asia.

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Microneedles fabricated with two-photon polymerization:
Credit: Royal Society of Chemistry

I first covered ACerS member Roger Narayan’s work in the field of two-photon polymerization a little more than a year ago in a story for ACerS’ membership magazine, the Bulletin. For several years, Narayan, a professor in the Joint Biomedical Engineering Department that is connected with NC State’s College of Engineering and the University of North Carolina at Chapel Hill, has been examining the use of this rapid prototyping approach using ceramic–polymer hybrid materials to create patient-specific microscale medical prostheses, scaffolds for tissue engineering and microscale medical devices.

One of set of applications he has been working on, in particular, is using two-photon polymerization to create arrays of fine microneedles. (Conceptually, Narayan’s polymerization process is like a 3D ink jet process that builds up structures on the nanoscale.)

Recently, Narayan coauthored a paper on the novel use of microneedles to deliver quantum dots into the skin. “Our findings are significant, in part, because this technology will potentially enable researchers to deliver quantum dots, suspended in solution, to deeper layers of skin. That could be useful for the diagnosis and treatment of skin cancers, among other conditions,” Narayan says in a news release from NCSU.

QDs, sometimes called “artificial atoms,” are semiconductor materials that fall into the category of nanocrystals, and they contain a variable number of electrons that occupy well-defined, discrete quantum states.

This groups is attracted to the use of QDs because of their ability to serve as fluorophores and also work as drug delivery vehicles. QD-based fluorescent probes can be engineered to be superior to organic dye fluorophore by being brighter and having better photostability (can fluoresce after one hour of continuous excitation), signal-to-noise ratio, emission ranges and fluorescent lifetimes. Researchers report they can use their intense fluorescence to track individual molecules.

Sample quantum dot with bio coating. Credit: Histesh R. Patel

At this point, Narayan and the other researchers just are using the microneedles on pig skin and can capture images of the quantum dots entering the skin using multiphoton microscopy. Although this work is still preliminary, these images allow the researchers to verify the basic effectiveness of the microneedles as a delivery mechanism for quantum dots.

The hope is that multiphoton microscopy will have clinical applications using real-time imaging materials such as the quantum dots for faster diagnosis of cancers or other medical problems.

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