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We employed an empirical molecular mechanical model and non-equilibrium molecular dynamics simulations to investigate the structure of aqueous solutions of some prototypical polar compounds upon microwave heating. Microwave irradiation has been taken into account implicitly by performing simulations at a rotational temperature exceeding the translational one (Tr> Tt). We studied aqueous solutions of 5 polar compounds (acetone, acetaldehyde, dimethylether, methanol, and acetonitrile), which have been recently classified as hydroneutral or hydrophilic, depending on their hydration number determined experimentally via dielectric spectroscopy. We have shown that the two groups of polar compounds could indeed be distinguished also based on the changes in their hydration upon a Tr increase. Moreover, we have clearly demonstrated the crucial effects of mass and charge distribution in a solute molecule on its hydration properties under the studied non-equilibrium microwave conditions.

We employed non-equilibrium molecular dynamics simulations to investigate the hydrogen-bond dynamics in bulk water upon microwave heating. Microwave irradiation has been taken into account implicitly by performing simulations at a rotational temperature exceeding the translational one (Tr > Tt). We have shown that the effect of an increased Tr results in a modified geometry of the average path for hydrogen-bond switch and in decreased characteristic decay times for the reorientation of a water molecule. We also confirmed the validity of the extended jump model to describe hydrogen-bond dynamics under the studied non-equilibrium conditions.

The query language OVAL which is intended for the integration with the database programming language based on C++ is proposed in this paper. The work addresses the impedance mismatch problem between the syntax and the semantics of the programming and query language. The query language OVAL is based on the functional query language FQL extending it for the manipulation of complex objects. The salient features of the OVAL query language are: (i) functional nature of the query language, which makes the language suitable for the integration with the procedural programming languages and provides modular style of query definition, (ii) the use of schema information for expressing queries and (iii) recursive evaluation of the algebraic operations on set structured complex objects.

The database model CDM intended for modelling design objects is presented. All properties of the design object are modeled by means of functions. For modelling dynamic dependencies among objects we introduce the notion of dynamic function . The dynamic function comprises capabilities for the description of the object static structure and algorithmic dependencies among objects. Some constraints and practical problems in using dynamic functions in the domain of geometric modelling are identified.