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A majority of nanomechanical deformation simulations of nanostructured components such as nanowires or nanocrystalline materials are regularly carried out using the classical molecular dynamics (MD). Due to the fundamental reason that the MD simulations must resolve atomic level vibrations, the microsecond scale nanomechanical deformation cannot be analyzed using MD with resulting disparity in experimental and nanomechanical simulation results. In this investigation a modified Hybrid Monte Carlo (HMC) method that can be used to analyze time-dependent atomistic mechanical deformation at higher timescales than currently possible using MD is established. For the purpose of comparison HMC analyses of a nanocrystalline Ni sample at a strain rate of 109 s–1 with three different timesteps, viz. 2 fs, 4 fs, and 8 fs, are compared with the analyses based on MD simulations at the same strain rate and with a MD timestep of 2 fs. It is found that the HMC simulation with a timestep of 8 fs correctly reproduces defect formation and the stress-strain response observed during MD simulations with an approximate speedup of 4 times in the simulation time. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

India is the world's dominant producer of crude Mentha arvensis oil, and exporter of its processed derivative, natural menthol. This status has been achieved through superior product price competitiveness resulting from progressive agronomic improvements that include a transition from cultivation of this mint as a semi-perennial to an annual crop. This paper describes and analyses recent developments in Indian M. arvensis cultivation. Observations were made during 1998/99 and 1999/2000 in the fields of 295 farmers in the central Indo-Gangetic plains area. The criteria recorded included: mint cultivars used; the planting, weeding, irrigation, pesticide application and harvesting schedules; crop health in relation to diseases and pests; yields of the harvested herb and the distilled essential oil; the oil menthol content; and the net income. Most of the farmers used the cultivar, Kosi. The performance and returns of Kosi transplanted in April had proved superior to Kosi and Shivalik suckers and to transplanted Shivalik. The returns from late-transplanted Kosi were in the range of Rupees (Rs) 25 000 to Rs 40 000 ha−1 (Rs 50≈US$1), similar to those from Kosi suckers and much higher than for both transplanted and suckers of Shivalik. This survey revealed that rotations of rice (Oryza sativa) with chickpea (Cicer arietinum) and mint, and pigeonpea (Cajanus cajan) with wheat (Triticum aestivum) and mint could be profitable in the central Indo-Gangetic plains. They also conserved inputs and were preferable to the conventional rice-wheat rotation. A re-survey in the summer of 2002 confirmed that recommendations made to farmers have led to the adoption of the Kosi and Himalaya cultivars in 80% of the survey region and that 70% of mint cultivation in the area occurs in the summer season.