introduction: in different investigations, the destructive effect of ultrasonic scalers on the margins of composites has been studied, but there are very few studies on the effects of ultrasonic scalers on the microleakage of poly-acid modified composite resin and resin modified glass ionomers. the main purpose of this study was to evaluate the marginal microleakage of class v preparations rest...

various scaling methods such as relative viscosity, peclet and reynolds scaling were used to find the best scaling law. scaling and modeling of the flow curves of various model emulsions consist of tragacanth gum (tg) (0.5, 1 % wt), oleic acid (5, 10% v/v) and wpi (2, 4 % wt) were investigated and the best models were selected. as these emulsions are non-newtonian, they do not obey the usual, si...

introduction: corrosion and scaling of water in distribution systems in spite of imposing economic and aesthetic problems can lead to adverse effects on consumers' health. the present study was conducted to evaluate the corrosion and scaling of water distribution system of sarableh city (ilam, iran) during summer and winter seasons in 2014. materials and methods: totally, 60 samples of wat...

Recursion relations for orthogonal polynominals, arising in the study of the one-matrix model of two-dimensional gravity, are shown to be equvalent to the equations of the Todachain hierarchy supplemented by additional Virasoro constraints. This is the case without the double scaling limit. A discrete time variable to the matrix model is introduced. The discrete time dependent partition functio...

Abstract. Matrix models of 2D quantum gravity are either exactly solvable for matter of central charge c ≤ 1, or not understood. It would be useful to devise an approximate scheme which would be reasonable for the known cases and could be carried to the unsolved cases in order to achieve at least a qualitative understanding of the properties of the models. The double scaling limit is an indicat...

How do species coexist? A framework known as modern coexistence theory can ‘measure coexistence' by partitioning invasion growth rates into mechanisms, terms which correspond to classes of explanations for coexistence. There are several reasonable ways define each depending on exactly how a perturbed low density (the invader) is compared other that remain at their typical densities residents). ...