Volume 12, Issue 3, 2012 July-September

Volume 12, No 3 Pages:
2012 July-September Articles: 6

Measurement of radon concentration in dwellings from the affected landslide area of Mamit town, Mizoram, India

Radon concentration in dwellings in Mamit town area has been observed for about two years from May 2009 to February 2011. Seasonal variations of these radon concentration levels were observed for a year and after which landslide took place in a part of Mamit town and indoor radon concentration levels were also measured in landslide affected area. Pre- and post-landslide radon data are compiled and compared. For this, indoor radon concentration measurement, a time integrated method was employed by using a solid state nuclear track detector (SSNTD) type (LR-115films) kept in a twin cup dosimeter. It was found that the radon concentration level during pre-landslide was more than that of the post-landslide level. This behaviour is similar to the changes of concentrations in soil-gas radon which is associated with the earthquake activities as observed in Garhwal Himalayas. The radon content in the soil gas measured using RAD7 even after the landslide phenomena was found to be not so high.

Introduction to band structure calculations using the LAPW method

This paper is a discussion on a brief introduction to the density functional theory (DFT). The formalism and the approximations made for easy computation has been mentioned along with the two theorems of Hohenberg and Kohn on which the density functional theory is based. In the end, the Kohn-Sham equation which turned density functional theory into a practical tool to obtain the ground state density has been explained along with the LAPW method.

Surface tension study of concentration dependent cluster breaking in acetone-alcohol systems

Alcohols are well-known for the formation of clusters due to hydrogen bonds. When a second molecular species such as acetone is added to an alcohol system, the hydrogen bonds are broken leading to a destruction of the molecular clusters. In this paper we report the findings of surface tension study over the entire concentration region of acetone and six alcohol systems over the entire concentration range. The alcohols chosen were methanol, ethanol, isopropanol, butanol, hexanol and octanol. Surface tension was measured using the pendent drop method. Our study showed a specific molecular interaction near the 1:1 concentration of lower alcohols and acetone whereas the higher alcohols did not exhibit the same.

Application of mathematics in business appraisal

Important mathematical tools/techniques for appraisal of business projects under certainty, risk and uncertainty conditions are discussed in this paper, including certainty equivalent method, risked adjusted discount rate method, expected monetary value (EMV) method, expected opportunity loss (EOL) method, criterion of optimism, criterion of pessimism and criterion of realism. Under Certainty equivalent and risked adjusted discount rate methods net present value (NPV) of the project/investment project is find out to enable the decision maker or the project manager whether to continue or reject or select the best among the alternatives. In cases of the business decision making under risk or probabilistic decision situations EMV and EOL are suitably used. In the absence of knowledge about the probability of any state of nature (future) occurring, the decision maker must base his decision only on the actual conditional pay off values. In such situations criterion of optimism, criterion of pessimism and criterion of realism as Hurwicz criterion are usefully applied.

Stress-strain in anisotropic solid medium

The numbers of elastic constants in the anisotropic medium has been investigated through the Cartesian co-ordinate plane symmetry. We have observed different types of anisotropic medium have different number of elastic constants. These constants are related with the properties of the medium.

Two interesting numbers π (pi) and φ (phi) [Nambar ngaihnawm pahnih – π (pi) leh φ (phi)]

The history and applications of π (pi) and φ (phi) are discussed.

MIPOGRASS Annual Report

Mizo Post Graduate Science Society (MIPOGRASS) hi June 10, 1995 khan NEHU, Shillong-ah din a ni a, Registration No. chu S.R. 42/96/MZ-RFZ of 1996 a ni. Mizoram in Science lamah hma a sawn theih nan sorkarah rawtna chi hrang hrang leh thurawnte pein theihtâwp a chhuah ve ṭhin a, tûnah hian a hlawhtlinna tam tak kan hmu mêk zêl a ni. Kum 2011-2012 chhûnga MIPOGRASS hmalakna leh hnathawh tlângpui report hetiang hi a ni.