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The present study reports a comprehensive molecular dynamics simulation of the effect of a) temperature (300–1073 K at intervals of every 100 K) and b) point defect on the mechanical behaviour of single (armchair and zigzag direction) and bilayer layer graphene (AA and AB stacking). Adaptive intermolecular reactive bond order (AIREBO) potential function was used to describe the many-body short-range interatomic interactions for the single layer graphene sheet. Moreover, Lennard Jones model was considered for bilayer graphene to incorporate the van der Waals interactions among the interlayers of graphene. The effect of temperature on the strain energy of single layer and bilayer graphene was studied in order to understand the difference in mechanical behaviour of the two systems. The strength of the pristine single layer graphene was found to be higher as compared to bilayer AA stacked graphene at all temperatures. It was observed at 1073 K and in the presence of vacancy defect the strength for single layer armchair sheet falls by 30% and for bilayer armchair sheet by 33% as compared to the pristine sheets at 300 K. The AB stacked graphene sheet was found to have a two-step rupture process. The strength of pristine AB sheet was found to decrease by 22% on increase of temperature from 300 K to 1073 K.

The phenomenon of self healing of cracks in bilayer graphene sheet has been studied using molecular dynamics simulations. The bilayer graphene sheet was subjected to uniaxial tensile load resulting in initiation and propagation of cracks on exceeding the ultimate tensile strength. Subsequently, all forces acting on the sheet were removed and sheet was relaxed. The cracks formed in the graphene sheet healed without any external aid within 0.4 ps The phenomenon of self healing of the cracks in graphene sheet was found to be independent of the length of the crack, but occurred for critical crack opening distance less than 5 A for AA stacked sheet and 13 A for AB stacked bilayer graphene sheet. Self healing was observed for both AB (mixed stacking of armchair and zigzag graphene sheet) and AA (both sheets of similar orientation i.e. either armchair-armchair or zigzag-zigzag) stacking of bilayer graphene sheet.

Molecular Dynamics simulations revealed the phenomena of self healing of cracks which were generated in graphene on application of tensile load exceeding its ultimate tensile strength. The phenomenon of self healing was observed when the system was studied at a very slow rate of 0.05 ps. Cracks initiated in the graphene sheet was allowed to propagate till it reached a critical length following which the load was removed and the sheet was relaxed. The study revealed that self healing of cracks took place within a critical crack opening displacement range of 0.3–0.5 nm in absence of any external stimulus. However, the self healing phenomenon was found to be independent of crack length. This self healing phenomenon occurred not only in pristine graphene sheet, but also in presence of pre-existing vacancies. The mechanism of self healing has been explained by detailed bond length/angle distribution analysis.

Retailing is not only an important aspect of the economic structure but very much a part of our lives. Its current contribution which is 10% of the country's GDP, proves its significance towards the growth of country's GDP. For centuries now, India has been operating within its own unique concept of retailing. In the words of David Gilbert retail is a business that guides its marketing effort towards the final consumer satisfaction primarily based upon the organization of selling goods and services as a way of distribution. It is sure and certain that India will be the destination for retailing as existing Indian middle class purchasing power is increasing at a rapid pace. Rural India can be considered as heart land of retailing. But according to Indian Market Research Bureau (IMRB) study 0.6 million villages in India did not have a retail outlet of any kind. Further, the outlet density in rural India is lower than that of urban India. It indicates a lot of potential being left untapped. The retail companies are rising in India at a remarkable rate year after year. And, they have brought upon a striking change in the shopping attitude of the Indian customer. Many major international retail enterprises such as TESCO, METRO AG, WAL-MART have already recognised the scope of growth in Indian retail industry. As India is the second fastest growing economy in the world, it provides plethora of opportunities and increasing scope for the Indian retail market. Investor have outstanding investment options in Indian retail segment and allied sectors. India has the uppermost shop compactness in the entire world with around 1, 20,000 shops diagonally the country. Furthermore over, India has been rated surrounded by the top 10 FDI destinations of the world.