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This report is devoted to the following plausible mechanisms of disintegration of mineral substances exposed to high-power electromagnetic pulses (HPEMP) with high electric field strength: loosening of mineral structure through electrical breakdown; disintegration due to development of mechanical stresses at the boundary between the dielectric and conductive mineral components; electromagnetic energy absorption by thin metallic films or layers thinner than the characteristic skin layer. Disintegration through these mechanisms would proceed efficiently only provided that the size of the mineral sample exposed to HPEMP exceeds a definite minimum value, which is due to low concentration of the irradiating energy.

The nonlinearity observed in piezoelectric behaviour of ferroelectrics like PZT needs to be modelled appropriately. Mainly the domain-switching phenomenon is the cause of this nonlinearity, which requires adoption of suitable switching criteria. In this paper, different domain switching criteria that describe the nonlinear behaviour are evaluated. The comparative study shows that there is considerable deviation from the experimental results. This calls for a better understanding of effects of domain parameters on the macroscopic behaviour of the ferroelectric material.

In nanomechanics, a systematic approach is required to deal with various expressions of intermolecular potential functions. A concept of universal atomic potential (UAP) is suggested in this paper to unify all the expressions of intermolecular potential functions. The UAP function aims to establish a systematic approach to express the intermolecular potential functions in terms of the UAP form. As examples, two kinds of potential function have been expressed in terms of the given UAP function.

A novel multi-scale method has been proposed for estimating the in-plane displacements of LSI lithography mask. In order to verify the applicability of proposal method, the mask of simple pattern has been simulated. The simulated results agree with experimental mask feature qualitatively. Moreover, simulation for real device pattern shows full-chip simulation can be performed in practical short time by using this method.

It is a well-known fact that ab initio programs imply a direct quantitative prediction of chemical phenomena from the first principles, thus providing most reliable and accurate results. The term ab initio (Latin) means from first principles and so ab initio quantum chemistry deals with calculations of molecular structure whereby no empirical parameters are included and all integrals are evaluated and thus is independent of any experiment. MOLPRO is an open source ab initio program which is approximately 200,000 lines of code written in Fortran. It is important to note here that an open source program MOLPRO and an open source operating system LINUX was seen as compatible. This paper presents the assessment of the implications of ab initio programs in molecular sciences and the optimized environment for MOLPRO 2000.

Molecular dynamics (MD) simulations of nanoindentation of polyhedral oligomeric silsesquioxane (POSS) materials HSiO (TH and POSS polymerized norbornene homopolymer (PNPOSS) at different temperatures were performed. Load-displacement curves were calculated, from which the hardness and elastic moduli at different temperatures were obtained. These results compare well with currently available experimental data and previous theoretical calculations. Surface adhesion and plastic deformation in POSS materials during nanoindention are investigated. The difference between the MD simulations of nanoindentaion and the actual ones are discussed as well.

Size-dependent stress concentration of nanocavities was investigated with EAM (embedded-atomic potentials) based molecular statics simulations. It was found that at nanoscale stress concentration factor of nanocavities decreases as the characteristic size decreases and this trend is not affected by grain orientations.

Three-dimensional molecular dynamics (MD) simulations of mechanical properties of copper nanowire have been carried out to study the size effects on the high strain-rate scale. It is found that the strain-rate scale of a nanosized structure is much higher than common materials. Even strain rate of 10/s can be considered as quasi-static loading rate for metal nanowires. The results from three different loading methods agree well to this finding, which proves that this high strain-rate scale can be true for small structures. The origin of such a high strain-rate scale is that structures with a length scale of nanometers can respond to the external loading very quickly.

Non-linear cable dynamics is investigated under a harmonic excitation. A set of non-linear partial differential equations is derived by the extended Hamilton’s principle. Global bifurcation cascades are provided to show the multiple solution structures with the variation of forcing amplitude. The ultimate steady state of the cable is sensitively dependent on initial conditions and evolution history of parameters. The coexistence of different solutions may induce a sudden jump in response under small perturbations, a new feature found in non-linear cable dynamics.

It is important to take into consideration the particle rotation when discussing the behaviour of deformation in granular material. A Cosserat continuum theory is suitable for the problems that include rotation of particles in granular materials because the deformation of a ground composed of granular materials is described by both displacements and rotations. In this study, laboratory tests were carried out to investigate the rotation behaviour of granular materials. Then, an elasto-plastic model for sand based on tij-sand model [1] was formulated within Cosserat continuum theory. Furthermore, the model is implemented into a finite element code for the numerical simulation of boundary value problems related to the tests. From a series of laboratory tests and simulations, results are compared and discussed in detail.