Carbon nanotubes improve metal’s longevity under radiation

One of the main reasons for limiting the operating lifetimes of nuclear reactors is that metals exposed to the strong radiation environment near the reactor core become porous and brittle, which can lead to cracking and failure. Now, a team of researchers at MIT and elsewhere has found that, at least in some reactors, adding a tiny quantity of carbon nanotubes to the metal can dramatically slow this breakdown process.

For now, the method has only proved effective for aluminum, which limits its applications to the lower-temperature environments found in research reactors. But the team says the method may also be usable in the higher-temperature alloys used in commercial reactors.

The findings are described in the journal Nano Energy, in a paper by MIT Professor Ju Li, postdocs Kang Pyo So and Mingda Li, research scientist Akihiro Kushima, and 10 others at MIT, Texas A&M University, and universities in South Korea, Chile, and Argentina.

Aluminum is currently used in not only research reactor components but also nuclear batteries and spacecraft, and it has been proposed as material for storage containers for nuclear waste. So, improving its operating lifetime could have significant benefits, says Ju Li, who is the Battelle Energy Alliance Professor of Nuclear Science and Engineering and a professor of materials science and engineering.

The metal with carbon nanotubes uniformly dispersed inside “is designed to mitigate radiation damage” for long periods without degrading, says Kang Pyo So.

Helium from radiation transmutation takes up residence inside metals and causes the material to become riddled with tiny bubbles along grain boundaries and progressively more brittle, the researchers explain. The nanotubes, despite only making up a small fraction of the volume — less than 2 percent — can form a percolating, one-dimensional transport network, to provide pathways for the helium to leak back out instead of being trapped within the metal, where it could continue to do damage.

Testing showed that after exposure to radiation, the carbon nanotubes within the metal can be chemically altered to carbides, but they still retain their slender shape, “almost like insects trapped in amber,” Ju Li says. “It’s quite amazing — you don’t see a blob; they retain their morphology. It’s still one-dimensional.” The huge total interfacial area of these 1-D nanostructures provides a way for radiation-induced point defects to recombine in the metal, alleviating a process that also leads to embrittlement. The researchers showed that the 1-D structure was able to survive up to 70 DPA of radiation damage. (DPA is a unit that refers to how many times, on average, every atom in the crystal lattice is knocked out of its site by radiation, so 70 DPA means a lot of radiation damage.)

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Mint can as anti-cancer drug!

Mint is known for its health benefits. Rich in antioxidants, this versatile herb is an integral part of Indian cuisine.

Apart from giving a distinctively tangy taste, this herb can now also be used as an anti-cancer drug!


Recently scientists at Central Institute of Medicinal and Aromatic Plants (CIMAP) Lucknow discovered that mint plant has medicinal values and can be used to cure cancer.

According to this incredible discovery, L-menthol compound derived from Mentha plant (scientific name of Mint) can be used in anti-cancer drugs.


The research, published in OMICS: A Journal of Integrative Biology, revealed that the compound can kill colon cancer cell line without affecting the normal cell line.



Cancer is a deadly disease which is not directly curable. L- Menthol not only stops the division of cancer cells but also prevents its growth and spread to other organs of the body.


CIMAP scientists also claims that the production of L-menthol is cost-effective and can be derived easily without damaging the plants.

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New Way Could Boost Battery Performance using Bee Pollen

Pollen — the pesky, sneeze-inducing stuff that makes allergy sufferers everywhere miserable — could be the next greatest thing in battery research, according to a new study.

Scientists at Purdue University, in West Lafayette, Indiana, have been researching ways to make better batteries, and recently discovered that pollen grains, and their unique microstructures, could be put to use as a more efficient type of energy storage unit.

Batteries are made up of three main parts: electrodes, an electrolyte and a separator. Each battery has two electrodes. One is the cathode, which is the positively charged end of the battery. The other is the anode, or the negatively charged end of the battery. The electrolyte runs through the anode and the cathode, divided by a separator, to create a current of electricity.


The scientists were trying to improve on conventional lithium-ion batteries, which are the types of batteries typically used in cellphones and laptops. A lithium-ion battery has an anode made of carbon — usually graphite — and a cathode made of lithium cobalt oxide. The electrolyte that runs through the battery is made of lithium salts, said Vilas Pol, lead author of the new study and an associate professor in the School of Chemical Engineering and the School of Materials Engineering at Purdue University.

"This is just the beginning of better batteries," Pol said.

The researchers found that if they could turn pollen into a carbon anode with a more useful microstructure than graphite, they might be able to create a battery with the ability to store more energy. The scientists took pollen from honeybees and pollen from cattails, a common plant found near many bodies of water in North America, and turned them into little pieces of carbon. They did this by superheating a section of bee pollen and a section of cattail pollen to 1,112 degrees Fahrenheit (600 degrees Celsius) in a space that was filled with argon gas, which stops the carbon from burning up like it would if it was just heated by itself in a conventional oven, Pol said.

The scientists then reheated the pollen-based carbon pieces to create more empty pockets in the pollen structure, which increases their capacity to store energy, Pol said.

The researchers tested both types of pollen-based carbons in lithium-ion batteries and found that cattail pollen-based carbon had more energy-storing capacity than the bee pollen-based carbon, according to the study. This could be because cattail pollen has a more uniform structure, since it is made up of only one kind of pollen, the scientists said. Bee pollen, on the other hand, comes from the many different plants visited by honeybees and has a more irregular structure.

Next, Pol and his colleagues are planning to investigate how to create a better cathode (to go along with the new anode) to further improve a battery's energy storage.

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ZIKA VIRUS USED TO SPREAD COMPUTER VIRUS [Really]

A malicious spam campaign has been set up by criminals seeking to capitalize on fears surrounding the Zika virus in Brazil.

Researchers at the security firm Symantec discovered an email purporting to be from Saúde Curiosa (Curious Health), a health and wellness website in Brazil. Within the email are links and attachments claiming to be instructions on how to eliminate the virus and the mosquitos that spread it.

One of the links, which causes computers to be infected with a form of malware called JS.Downloader, has been clicked more than 1,500 times.

The outbreak of the Zika virus has been declared a Public Health Emergency of International Concern (PHEIC) by the World Health Organization (WHO) following a significant spike in birth defects in South America.

The email discovered by Symantec attracts the recipient’s attention with the subject line “Zika virus! Isso mesmo, matando com agua!, which translates to: “Zika Virus! That’s right, killing it with water.”

“Newsworthy events on a regional or global level often provide fertile ground for cyber-criminals seeking to capitalize on the interest in these events,” Satnam Narang, a senior security response manager at Symantec, said in a blogpost describing the spam campaign.

“In this case, the Zika virus’ impact in countries like Brazil is being leveraged, while the potential impact in other countries makes it a prime candidate for more malicious spam.”

In order to mitigate against such threats, Narang warns web users to be aware of unsolicited messages about the Zika virus and avoid clicking on links or opening attachments.

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