Research Highlight: Nanotransfer printing (nTP) set a record low sub-100 nm feature resolution

Researchers at the University of Tennessee (UT) and Oak Ridge National Laboratory (ORNL) developed a new protocol of creating silicon stamps for highly efficient nanotransfer printing (nTP). Current approach mainly relies on in situ formation of a fluoropolymer release layer immediately following anisotropic plasma etching of silicon. The potential of a current nTP approach has been demonstrated by imprinting various functional test structures of low nanometer scale (J. Am. Chem. Soc., DOI: 10.1021/ja201497a).

Deepak Bhandari, graduate student at UT, described the findings as "a technological improvement of nTP feature resolution down to sub-100 nm".

 

A native of Nepal, Deepak obtained both his bachelor and master degree in chemistry from Tribhuvan University, Nepal. After joining UT in Fall 2006, Deepak focused his research on "surface-enhanced Raman Scattering substrates development using both conventional and nanolithographic approaches". Graduating this May 12^th, Deepak joined ORNL as a postdoctoral research associate and plans to pursue career in academia after short postdoctoral experience.

source: http://www.chem.utk.edu/news/SepaniakGroupResearchManuscriptPublishedinJACS.html

More than 1/3rd of Americans and ½ of Germans live within 75 km of a nuclear power plant

Anant Babu Marahatta
Sendai, Japan

Disaster is a disaster. This time, Japan is victimized. No one knows, such catastrophe may happen anytime, anywhere, in the world.　

The current world news is about the crippled Fukushima based Japanese nuclear power plants which was hit by a 9.0-magnitude quake on March 11 of 2011 and then, about 25 minutes later, a devastating tsunami. About 172,000 people lived in the 30-km zone of these plants.

The Japanese government has declared the 20-km evacuation area around the crippled Fukushima No. 1 nuclear power plant a “no-go zone”. It has also urged the residents to abide by the order for their own safety or possibly face fines or detention. Under a special nuclear emergency law, people who enter into the zone will now be subject to fines of up to ¥100,000 and possible detention of up to 30 days.

In order to aware this potential risk of this scenario to the world, a current study released by “Nature” on Friday, 22nd April 2011, shows that about 90 million people worldwide live within 30 kilometers of a nuclear reactor, equivalent to the exclusion zone around Japan's crippled Fukushima plants. The United States alone has nearly 16 million people within this range, followed by more than 9 million each in China, Germany and Pakistan, and 5 to 6 million in India, Taiwan and France.

When the radius is expanded to 75 km, the number of people potentially at risk in case of a nuclear accident jumps to nearly half a billion. More than 110 million are in the U.S., 73 million in China, 57 million in India, 39 million in Germany and 33 million in Japan.

Let’s look at another way; more than 1/3rd of Americans live within 75 km of a nuclear power plant, and nearly half of all Germans.

It does suggest how many people will be at risk if something does go terribly wrong, as happened in Fukushima a month ago and in Chernobyl 25 years ago.

Sources:
‘The Japan Times” daily newspaper.
www.nature.com

A Chemical to capture radioactive substances: "Fukushima-reactors issue"

Anant Babu Marahatta
Tohoku university
Japan

Nuclear energy can be both beneficial and harmful, depending on the way in which it is used. We routinely use X-rays to examine bones for fractures, treat cancer with radiation, and diagnose diseases with the help of radioactive isotopes. Approximately 17% of the electrical energy generated in the world comes from nuclear power plants. 'Nuclear reactors produce electricity so cheaply that it is not necessary to meter it. The users pay a fee and use as much electricity as they want. Atoms provide a safe, clean and dependable source of electricity. '

On the other hand, nuclear hazard which literally means “risk or danger to the human health or to the environment caused by radiation emitted by the radioactive nuclei of a given substance, or the possibility of an uncontrolled explosion originating from a nuclear fusion or fission reaction of atomic nuclei”, that appeared in the Japanese “Fukushima nuclear plants” is the latest example of its negative impact. .

The contamination of the coolant (by radioactive iodine, cesium, and strontium), a mandatory process during nuclear chain reactions, caused by the “Fukushima nuclear reactors leakage” is the current issue of the world. To remove such radioactive substances, recently, a Japanese chemist and a domestic company have jointly developed a powdery chemical that can capture and precipitate radioactive substances in water.

This powder, made of various chemicals and minerals, including zeolite, can remove radioactive substances such as iodine, cesium and strontium, a professor at Kanazawa University said. The powder was able to remove almost 100 percent of cesium when 1.5 grams of the powder were mingled with 100 milliliters of water in which cesium had been dissolved at a density of 1-10 ppm. It has been confirmed to have the ability to remove iodine even at a density of 100 ppm. It is reminded that the densities of radioactive substances seeping into the water at the Fukushima No. 1 nuclear complex are estimated at around 10 ppm. This powder could be used in the ongoing effort to deal with contaminated water at the crippled Fukushima nuclear plant

Regional Chemistry Seminar in Biratnagar on May 7-8, 2011

INVITATION

We are delighted to inform you that Department of Chemistry, Mahendra Morang Adarsh Multiple Campus (Tribhuvan University), Biratnagar with collaboration of Nepal Chemical Society organizing the Regional Chemistry Seminar in Biratnagar, Nepal from May 7- 8, 2011.

We would like to invite you to attend the Seminar and make a grand success.

We look forwards to welcoming you soon in Biratnagar, Nepal

Post Graduate Department of Chemistry
Mahendra Morang Adarsh Multiple Campus, Biratnagar, Nepal

Chemistry Matters: Beauty

From molecules to equations to experiments, learn how and why chemistry is beautiful to Nobel Laureates. This video is one in a series of four, short educational videos capturing 16 Nobel Laureates' opinions on why chemistry matters. 

Chemists Can DANCE!

Potentiometry in Analytical Chemistry

This article was published in SPECTRUM, a science magazine published by ChemSA-Central Department of Chemistry, TU in 2005. I do not know whether this magazine is still being published or not. Since this magazine was published in printed copy only and I had its electronic copy, I want to share it with wide range of readers through NepaChem.-Basant Giri

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Potentiometry is one of the methods used for quantitative analysis in analytical chemistry. Here potential of an electrode in equilibrium with an ion to be determined is measured. There are two ways to quantify the given substance using potentiometry. One is direct Potentiometry and other is potentiometric titration. In direct potentiometry a single measurement of electrode potential is used to determine the concentration of an ionic species in solution.

Potentiometric Titration

In potentiometric titration, the end point is determined by measuring the potential of an indicator electrode as a function of the volume of titrant added. Beherend, in 1893 performed potentiometric titration of chloride, bromide and iodide with mercurous nitrate.

In a simple arrangement for a manual potentiometric titration a reference electrode (e.g. saturated calomel electrode or silver-silver chloride) is coupled with an indicator electrode, which is reversible with one of the ions involved in the titration. The emf of the cell containing the initial solution is determined and emf of the cell after each addition of titrant solution is also measured. Sufficient time should be allowed after each addition for the indicator electrode to reach a reasonably constant potential (~ 1-2 mV) before the next increment is introduced. In this procedure, we are concerned with changes in emf of the cell which is due to the change in concentration of ions reversible to the indicator electrode. Advantages of potentiometric titrations over 'classical' visual indicator methods are:

1. Can be used for coloured, turbid or fluorescent analyte solution.
2.  Can be used if there is no suitable indicator or the colour change is difficult to ascertain.
3. Can be used in the titration of polyprotic acids, mixtures of acids, mixtures of bases or mixtures of halides.

Polychar 19 Successfully Held in Kathmandu, Nepal

Polychar 19 was held in Kathmandu, Nepal on 20-24 ^th March 2011.

The conference was inaugurated by Nepali Prime Minister Jhal Nath Khanal on Sunday of 20^th March 2011.Prof. Witold Brostow, President of Polychar, University of North Texas, USA, Dr. Rameshwar Adhikari, Polychar 19, Convener, Tribhuvan University, Nepal

I found the Polychar 19 International Conference was the Biggest Scientific Gathering for Nepal. The gathering made a history for Nepal. Renowned Scientists from 50 Countries discussed the recent trends and new avenues of Advanced Materials during the meeting. The technical Program was 162 oral presentations including 6 plenary lectures and 180 posters.