Happy Birth Day Bunsen: The inventor of Bunsen Burner

Watch the video.

What is Nuclear Disaster? # Nuclear Reactor Leaking in Japan# Video

Last few weeks Japan is facing natural and man made disaster. After the massive earthquake, Sendai and neighboring regions were heavily affected by Tsunami which causes huge loss of human life and other physical structures. Tsunami also damaged nuclear power plant. There are lots of rumors about harmful radiation leaking from the damaged power plant. Video below explains in simple way about nuclear power plant and its safely issues.

NCS organizing International Conference on Advanced Materials and Nanotechnology for Sustainable Development # Nepal Chemical Society

The International Conference on Advanced Materials and Nanotechnology for Sustainable Development” will be held in Kathmandu, Nepal on October 21-23, 2011. The objective of this conference is to capitalize on the rapidly growing field of advanced materials and nanotechnology, bringing together expertise from across the international and national academic communities, as well as industry. The remarkable evolution of nanotechnology has only been possible because of close collaborations between chemists, materials and biological scientists well as industrialists. This conference aims to bring together such diverse specialists, and to understand the requirements of materials science and nanotechnology research for sustainable development in an emerging country like Nepal.

This conference covers a series of symposia, which have been selected to accommodate a wide range of interests. The purpose of this meeting is to facilitate interdisciplinary interactions between scientists engaged in the full spectrum of research, development, and applications, and to discuss the current status and recent developments of these materials for the improvement of human lives.

In addition, the conference will provide an opportunity to enjoy the natural beauty and biodiversity of Nepal. The conference covers following topics but not limited to

Symposium A: Advanced Functional Nanomaterials, and Nanocomposites

Symposium B: Supramolecular Chemistry, Self-Assembly and Interfaces

Symposium C: Electrochemistry, Corrosion Science, and Materials for Energy

Symposium D: Polymers, Gels, and Aggregates

Symposium E: Microfluidics, Separation and extraction Sciences

Symposium F: Formulation and Application of Bio-Nanomaterials, Photocatalytic Materials,

Photochemistry and Elementary Process

Symposium G: Chemistry for Environment Protection and Interdisciplinary Sciences

Symposium H: Special Session for Young Scientists (PhD students and young post-docs only)

Important dates

Registration :

Opens: Feb 15, 2011

Closes: Aug 15, 2011

(Discounted rate ends)

Abstract :

Opens: Feb 28, 2011

Closes: Jun 15, 2011

Notification: Jul 15, 2011

Full paper submission for proceedings :

Opens: Jul 15, 2011

Closes: Sept 30, 2011

Hotel booking :

Opens: Jul 15, 2011

Closes: Sept 30, 2011

visit Nepal Chemical Society website for detailed information!!

DEATH BY OXALIC ACID

Anant Babu Marahatta
Tohoku University, Japan

Oxalic acid is a constituent of many house hold products. It is found in many disinfectants, household bleach, metal cleaning liquids, antirust products and furniture polishes. Oxalic acid is a crystalline, colorless substance and is efflorescent. This means it tends to become powdery on account of loss of water of crystallization. It has got its name from the Greek word Oxalis, which means sorrel. It occurs in sorrel plant and because of this the French chemist Lavoiser in 1787 named it as Oxalic acid. It occurs in the leaves and young stalk of Rhubarb, Spinach and even Cabbage. Sorrel is succulent acid herb used in salads.

Accidental poisoning has been known to occur after a hearty meal of rhubarb or sorrel .Food rich in oxalate can also lead to kidney stones because kidney stones are generally made up of oxalates. Crystals of oxalic acid are similar in appearance to those of magnesium sulphate (Epsom salt) and zinc sulphate. Because of this similarity, cases of accidental poisoning have occurred. Magnesium sulphate in doses of 15g is used as a laxative (to facilitate the evacuation of Bowels) and is non toxic. Since oxalic acid, a dangerous poison is so similar looking to Epsom salt-a commonly used drug as laxative medicine-it is necessary to be able to differentiate between the two. If the doctor or nurse fails to differentiate between the two, accidental poisonings may occur. Two patients at the mental hospital in Scotland had died in 1956 after receiving doses of oxalic acid which was mistaken for Epsom salts. Similarly zinc sulphate is also commonly used drug and looks very similar to the dangerous poison, oxalic acid. Thus in order to remain in the safe side, it is very much essential to be able to differentiate between them.

HOW DO DOCTORS DIFFERENTIATE BETWEEN THE TWO?

Since if we taste a small amount of crystal of each, oxalic acid is sour in taste and magnesium sulphate is nauseatingly bitter and zinc sulphate is metallic bitter. But surely, this is not the best method to find out the poison. The reaction of oxalic acid is strongly acidic but that of zinc sulphate is slightly acidic and magnesium sulphate is neutral. On application of heat, Oxalic acid sublimes while the rest of the two salts remain fixing. When each salt is allowed to react with sodium carbonate, oxalic acid shows effervescence but no precipitate while the other two salts show no effervescence but a give white precipitate of metal carbonates. But perhaps the easiest test is to see whether stains of ink will disappear by a solution of one of these salts or not. Since, a solution of oxalic acid makes the stain disappear ,the other two salts can not do that That is why oxalic acid is used in products like ink removers and furniture polishes. It is also used in households as a “bleach” to remove stains or to clean metals notably brass or leather and also used in calico-printing (cotton cloth especially plain white and unbleached).

CAN OXALIC ACID BE USED FOR HOMICIDE?

No that is not possible .because of its sour taste; it has not been used for homicide. Oxalates have however been used to procure abortion by vaginal injection.

HOW DOES OXALIC ACID AFFECT THE HUMAN BODY?

Oxalic acid has both a local and systemic action on the body. By local action, i.e. the action on stomach and intestinal walls with which it comes in contact. By systemic effect i.e. remote effects on organs with which it does not really come in contact. Oxalic acid readily corrodes the mucus membrane of the digestive tract. Unlike corrosive mineral acids and alkalis, oxalates do not lose their poisonous properties when diluted. On the contrary, dilute solution of oxalates can cause grave systemic effects. Oxalic acid however rarely damages the skin.

As far as systemic effects are concerned, large doses of oxalic acid can cause death due to shock. Oxalates can readily combine with the Calcium ion in the body tissues, causing a precipitous fall in the level of ionized calcium. This can cause muscle irritability, tetany and convulsions and irregular action and slowing of the heart. Since all muscle cells in the body are very much dependent on calcium for their proper functioning and it includes heart muscle too.

WHAT ARE THE SIGNS AND SYMPTOMS OF OXALIC ACID POISONING?

The symptoms of the oxalic acid poisoning depend on the size and concentration of the dose. A large concentrated dose would kill with in a couple of hours by shock or hypocalcaemia (lowering of calcium levels in the blood).A large dilute dose would cause kidney failure. There is immediate sour or bitter taste associated with a burning sensation in the mouth, throat and food pipe because of the corrosive action of the oxalic acid. There is eructation (formal belching-emit wind noisily through the mouth), distension(Swell out by pressure) of abdomen, thirst, nausea and vomiting. The vomit has a coffee ground appearance because the oxalic acid badly corrodes the stomach walls. There may be bloody vomiting for the same reason. Finally shock supervenes and death occurs. Acute poisoning occurs when the moderately large dose is taken and in such cases, the person survives up to 48 hrs. The symptoms are muscle irritability, tenderness, tetany, convulsions, numbness (paralyzed) and tingling (feel a slight stinging) of the finer tips and legs, cardiac irregularity, slowing of the heart, ventricular fibrillation (irregular and fast beating of the ventricles of the hearts).Delayed poisoning may occur when a smaller dose is taken. This may lead to renal failure and uremia. Death occurs with in 5-14 days.

HOW EXACTLY DID THE DOCTOR MAKE OUT THAT IT WAS THE CASE OF OXALIC ACID POISONING?

The person poisoned with the oxalic acid runs down the strange streaks from the angles of the mouth. Due to corrosion, there is whitening or yellow-white discoloration of the lips, lining of the mouth and upper surface of the tongue. The lining of the stomach in oxalic acid poisoning is blackened by the production of acid haematin. There may be superficial corrosion. The stomach may contain fresh or altered blood. Furthermore crystals of calcium oxalate can be demonstrated in scrapings of the stomach mucosa. The kidneys of a person dying of oxalic acid poisoning are congested and swollen with oedema (accumulation of excess fluid in body tissues). The renal tubules even contain the oxalate crystals. Thus doctors may sure it is the case of oxalic acid poisoning.

Chemistry Beyond the Textbook: 16 Nobel Laureates Speak

Learn about chemistry's many facets as explained by Nobel Laureates and discover why would one claim that chemistry is the 'queen of all sciences'. This video is one in a series of four, short educational videos capturing 16 Nobel Laureates' opinions on why chemistry matters.

Nepalese Chemists Get Together in Kansas, USA

Some Nepalese Chemists in the USA had informal get together in Manhattan, KS last weekend. Kansas State University has more than one dozen Nepalese Chemists working as graduate student and post doctoral research associate. Possibly this is the largest number of Nepalese Chemists in any single University. I headed from Wyoming to Manhattan, KS driving ~11 hours. Binod Pandey, Surendra Dawadi, Mahesh Poudel, Sitaram Acharya and their family members joined us from University of Missouri, St. Louis. In the Manhattan, Kansas State University: we were received by Nepalese Chemists and their family. It was a very nice get together. I was amazed by the hospitality we received from all Manhattan Chemists family.

We talked about chemistry in Nepal along with our research. It was very nice get-together. KSU has following Nepalese Chemists: Bhanu Bhakta Neupane, Bipin Pandey, Keshar Prasain, Khadga Man Shrestha, Khem Prasad Acharya, Laxman Pokhrel, Lila Ballav Pandey, Mahendra Thapa, Raj Kumar Dani, Dr. Damber Hamal, Dr. Tej Shrestha, Amita Neupane. I may not have remembered some of the names. These bright names have shown that Nepalese Chemists are competitive in the world by winning variety of awards and publishing research results in peer reviewed journals.

We will probably meet again in ACS national meeting-fall 2011 in Denver.

Here are some pictures from the get-together.

Kansas State Premises

In front of Chemistry Building

@ Tuttle Creek Lake

-------------------

Basant

Three post-doctoral positions available in Chemistry at Trinity University, TX USA

The Department of Chemistry at Trinity University has three post-doctoral positions openings in following categories. This university is in San Antonia, TX USA. Chemistry department in this university is primarily undergraduate education. If you are interested working on small department for undergraduate students and small research group, follow following links.

• Analytical Chemistry: 

 Candidates must have a Ph.D with a specialization in analytical chemistry. The ideal candidate will have experience in at least one of three areas: the development of porous polymer monoliths, capillary separations, or chromatographic theory development. The ideal candidate will have an interest in pursuing a career at a Predominantly Undergraduate Institution (PUI) with both teaching and research expectations. Assistance with the supervision of undergraduate researchers, and the presentation of research results is expected. 

Teaching opportunities, of up to one course per semester, at both the lower and upper division, in laboratories and lecture courses are provided and such participation is encouraged. Participation in departmental and university mentoring and professional development activities is encouraged. 

Applicants should send a letter of application indicating current career plans, vitae, (unofficial) undergraduate and graduate transcripts, evidence of teaching effectiveness (if available), and arrange for us to receive two letters of reference upon request. Review of applications will begin immediately and will continue until the position is filled. The start date is flexible and is as early as 5/1/2011. Trinity University is an equal opportunity employer. 

Women and minorities are encouraged to apply. Send materials to Dr. Michelle Bushey, Department of Chemistry, Trinity University, One Trinity Place, San Antonio, Texas 78212-7200. 

Application materials may be sent via e-mail to:  mbushey@Trinity.edu. Inquiries can also be addressed to mbushey@trinity.edu. Electronic submissions must be followed by mailed hard copies. Further information is available at http://web.trinity.edu/x5065.xml and http://www.trinity.edu/mbushey/

• Biochemistry

Applicants must have a PhD in chemistry or biochemistry, and have a genuine interest in working with and mentoring talented undergraduate researchers.  The Hunsicker-Wang group works on Rieske proteins, specifically using mutatgenesis and chemical modification to understand the pH-dependent reduction potential.  This is a full-time research position and does not require a teaching commitment.  However, there will likely be opportunities to gain classroom or laboratory teaching experience.  This position is ideal for individuals interested in pursuing a career at a primarily undergraduate institution.  A background in chemistry or biochemistry is needed, with experience in any one of the following fields preferred: protein purification, site-directed mutagenesis, electrochemistry or protein crystallography. 

Applications should include a complete curriculum vita, 2-3 letters of recommendation, (unofficial) undergraduate and graduate transcripts, and a brief statement of why this position is of value to the applicant. The start date is flexible but could begin as early as 5/1/2011.  The position will remain open until filled, but interested candidates are encouraged to apply soon.    Trinity University is an equal opportunity employer. Women and minorities are encouraged to apply. Send materials to Dr. Laura Hunsicker-Wang, Department of Chemistry, Trinity University, One Trinity Place, San Antonio, Texas 78212-7200. 

Application materials may also be sent via e-mail to Dr. Hunsicker-Wang, lhunsick@trinity.edu.

For more information, please see http://www.trinity.edu/lhunsick/ or http://web.trinity.edu/x5065.xml.

• Organic/Inorganic Chemistry (more information to come)

If you want to know informal details regarding the department and the place you may contact Dr. Basu Panthi @ panthibdgmail.com

Practical approaches of Quantum Chemistry [part 4] : Semi-empirical Quantum chemistry

Anant　Babu Marahatta
Ph.D. student in Chemistry
Tohoku University
Japan

(This article is intended to introduce the semi-empirical techniques of Quantum chemistry) I am a part of it and currently mastering on “Density Functional Tight Binding (DFTB) approximation with and without Gaussian” by implementing them to investigate the rotational dynamics of the “Molecular Gyroscope”.

(Interested fellows are suggested to read Part 1 to part 3 of this article before proceeding it. And if necessary, you are reminded to consult the article “Computational Chemistry” archived herewith.)

Unlike the ab initio techniques [part 3] which are based entirely on the solution of the Schrödinger equations, semi-empirical techniques employ experimental results. In order to simplify the approximation, such techniques use parameters derived from the experimental data to the Schrödinger equation.

Basically, semiempirical techniques attempt to address the limitations like slow speed and low accuracy by omitting or parameterizing certain integrals based on experimental data, such as ionization energies of atoms, or dipole moments of molecules. As a result, semi-empirical methods are very fast, computationally inexpensive and applicable to very, very large molecules, and may give accurate results. However, accuracy of such methods lacks consistency on many systems.

Following animation explains about the action of the Quantum Molecular Dynamics Simulations of Molecules on a Metal Surface.

In computational chemistry, consideration of the more accurate methods (ab initio techniques) to study the molecular systems consisting thousands of atoms is impossible. The same is valid well to the case of crystalline solid even bearing medium sized molecules due to the inclusion of periodic boundary condition (PBC). In such cases, semi-empirical techniques are the good option. Similarly, in order to obtain the starting structure for an ab initio calculations (eg. Hartree-Fock, Density functional theory etc.), one might run semi-empirical calculations. However, the limitations of them must be considered before selecting the proper one and the level of accuracy depends on the system to be studied.

Semi-empirical methods may only be used for systems where parameters have been developed for all of their component atoms.　In addition to this, types of problems on which they do not perform well include hydrogen bonding, transition structures, van der Waals type interactions and so on. AM1 (Austin Model 1), AM1* (extended AM1), PM3 (Parameterized Model number 3) and MNDO (Modified Neglect of Differential Overlap) are the best known semi-empirical methods which can be run using Gaussian scheme.

The very recent approach “DFTB technique” especially focused to the solid state science has become a very popular for exploring the solid state dynamics computationally. I am also a part of it and mastering on “DFTB with and without Gaussian” by implementing them to investigate the rotational dynamics of the crystalline “Molecular Gyroscope”.

References:
http://www.chm.bris.ac.uk/motm/pentacene/pentacene.htm

Congratulations Dr. Jiba Raj Acharya for completing his PhD

In his Defense seminar

Jiba Raj Acharya successfully defended his PhD degree at Department of Chemistry, Louisiana State University, USA. His PhD research was focused on "Design, Preparation and Studies of Ratiometric Fluorescent Chemosensors Based on the Attenuation of Excitation Energy Transfer". On behalf of all Nepalese Chemists, we would like to congratulate him for this achievement and we wish for his better future.

More about his research on his own words:

In this Ph.D. studies targeting on the control of excitation energy migration in conjugated systems, I designed surface-immobilized monodispersed oligo(p-phenylene ethynylene)s (OPEs) as general basis for thin-film ratiometric fluorescent chemosensors. The sensor molecules have been functionalized with a specific analyte receptor at one end and a linkage for the covalent attachment to a glass surface at the opposite end. Upon surface immobilization, they form a highly ordered monolayer with the receptors positioned at the monolayer surface. Analyte binding to the receptor causes attenuation of the HOMO–LUMO gap at the receptor terminus, leading to the ratiometric change in fluorescent emission. The thin-film sensors for L-cysteine, pH, Zn2+ and NO were prepared and studied in detail to uncover a number of unusual properties, thus demonstrating the potential of this platform as a universal foundation for designing a broad range of ratiometric fluorescent thin-film chemosensors. The use of two fluorophore based surface-immobilized thin-film sensor is a novel approach and provides more reliable, accurate, easy to operate, and quantify the ratiometric fluorescent signals generated upon analyte binding.

Check his paper: J. Am.Chem.Soc.2009, 131, 880-881