Monthly Archives: February 2017

Longer lasting batteries

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This is a guest blogpost by Aya Nader.

Using two dimensional oxide anodes with a controlled number of atomic layers is an effective way to prolong the cycle life of Na (sodium) ion batteries, scientists from Saudi Arabia have revealed in a new research. The advancement carries great potential for grid storage.

Batteries normally have two electrodes: anode and cathode. Anodes can be manufactured from different materials, including oxides, sulfides, and phosphides. Usually, oxide anodes such as tin monoxide (SnO) go through massive volume change and degrade significantly after use, seriously shortening the life cycle of a sodium ion battery. Typically, researchers mixed the oxide anodes with carbon-based materials such as graphene to mitigate this large volume change.

“However, the new approach stacks few atomic layers of two dimensional SnO anodes to suppress this volume change, making batteries that last more than 1000 cycles,” explains Husam N. Alshareef, principal investigator of the study and professor of functional nanomaterials and devices at King Abdullah University of Science and Technology (KAUST), Saudi Arabia.

They used two dimensional materials made up of sheets of atoms, or atomic layers, stacked on top of each other. The thinnest SnO nanosheet anodes (two to six SnO monolayers) exhibited the best performance according to their study, published in the journal Nano Letters. As the average number of atomic layers in the anode sheets increased (beyond 10), the battery performance degraded proportionally and remarkably, the study found.

Now, the researchers are trying to combine the SnO anodes with suitable cathode materials to create full cell sodium ion batteries. The idea is to use these batteries to power small devices, such as phones and other electronic devices, and test their cycling performance in more realistic conditions.

In addition, the scientists plan to try charging up the batteries using solar power. Practically, sodium ion batteries are candidates to replace lithium ion batteries, especially in stationary storage applications, as sodium is cheaper and more available than lithium.

“Our progress using SnO anodes has resulted in stable sodium ion batteries that offer competitive capacity for grid scale applications,” says Fan Zhang, PhD researcher and lead author of the study. “This is exciting because it means a more effective storage solution has been identified for grid storage applications.”

UAE’s first nanosatellite launched

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Nayif-1 before it was shipped out of the UAE for the launch.

Nayif-1 before it was shipped out of the UAE for the launch.{credit}@Nayifone on Twitter{/credit}

The United Arab Emirates first ever nanosatellite, Nayif-1, was launched a few hours earlier – it was among 104 satellites propelled into outer space on board the PSLV-C37 rocket from Satish Dhawan Space Centre in India.

It’s the Gulf country’s first CubeSat mission led by seven Emirati engineering students from the American University of Sharjah, in collaboration with the Mohammad bin Rashid Space Centre. The first signal was heard in North America during the night hours (local time), roughly 18 minutes into the launch.

The AUS team will monitor the satellite’s direction and control until it’s switched to autonomous mode.

An educational CubeSat project, Nayif-1 will send and receive messages that will be picked up by amateur radio frequencies; it’s programmed to transfer messages in Arabic, also a first.

A CubeSat is a type of miniaturized satellite for space research that is made up of small cubic units, with a mass that typically doesn’t exceed 1.33 kilograms per unit. They often use commercial off-the-shelf components for their electronics and structure.

According to its makers, the Emirati CubeSat also holds an active control system board that is being launched in space for the first time.

Nanotechnology-armed green tea can battle cancer

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The green tea compounds are encapsulated in nanoparticles.

The green tea compounds are encapsulated in nanoparticles.{credit}Getty Images/TongRo Image Stock RF/Thinkstock Images{/credit}

This is a guest blogpost by Aya Nader

Researchers discovered that they can inhibit the growth of prostate cancer cells using nanotechnology to properly deliver a green-tea-based polyphenol.

To improve the outcome of compounds used to inhibit, delay, or reverse carcinogenesis, an international research team shows that adding nanotech materials to a drug delivery system can aid both prevention and therapy of prostate cancer.

“We formed a basis for the use of nanoparticle-mediated delivery to enhance bioavailability (absorbtion) and limit any unwanted toxicity of chemopreventive agents,” explains Imtiaz Siddiqui, lead researcher of the study, published last week in Scientific Reports.

The green tea polyphenols are encapsulated in nanoparticles. The polyphenol used here is epigallocathechin-3-gallate, better known as EGCG; it’s the most active green tea polyphenol component, according to the research team.

Through stopping the formation of blood vessels which nourish cancer cells, the nanoparticles-coated tea polyphenol starves the ‘bad’ cells to death.

The new study is an extention of a 2009 one where the same research team, including an Egyptian researcher from Al-Azhar University, introduced the concept of utilizing nanotechnology for enhancing the effects of chemoprevention by encapsulating bioactive agents – compounds (green tea polyphenol in this case) that have an effect on living organisms.

The 2009 study “was the first one on the subject and since then the concept has been used worldwide by different researchers and is currently a developing field in cancer management,” says Siddiqui.

The nanoformulation containing EGCG also inhibits the growth of new blood vessels, through which tumors get more blood supply to grow and develop; ultimately allowing the cancer cells to move to other parts of the body.

“There will be no side effects with stopping the formation of blood vessels,” says Siddiqui, adding that the effects will be tumor-specific and in turn will not affect the normal growth and formation of the blood vessels.

While there are some other publications which have suggested a similar mechanism, the data in the new study suggests that nanoparticles raised inhibition of cancer cell growth from 10% with 20 µM EGCG, to up to 50% at the same dose when delivering EGCG by nanoparticles.

In response to a question about dosage, Siddiqui says “It was earlier thought that 12 cups of green tea a day will be good however with our approach I am assuming that one or two capsules a day will suffice”. Siddiqui is referring to his encapsulated green tea formula, not regular green tea pills.

Most of the natural agents have shown “wonderful results” in cell culture and animal model testing, but these effects have yet to be translated to clinical studies because previously, the delivery system was still a work-in-progress and absorption of the drug was relatively low, according to the study, something that Siddiqui and his colleagues say they ‘fixed’ in their new study.

“Our study has paved a way for a different outlook to enhance the effects and will possibly lead to a better outcome clinically. It is difficult to mention how long it will take before initiating a clinical trial but it appears that we are on the right path,” he concludes.