The solubility of potassium dihydrogen phosphate (KDP) was determined for five different temperatures. Metastable zone width of aqueous solutions of KDP saturated at different temperatures was determined by nucleation method in pure form and adding a well-known chelating agent ethylenediaminetetraacetic acid (0.5 mol% EDTA). The induction period was measured, experiments were performed at selected degrees of supersaturation (), and the critical nucleation parameters like interfacial energy () were calculated, based on the classical theory of nucleation. The structural and optical properties of the grown crystals have been investigated. FTIR analysis has been carried out to characterize the grown crystals. Band gap has been calculated from transmission spectra.

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Pin reinforced foam cores with composite facesheets offer a viable means of structural construction owing to their low weight and high stiffness and strength. In this paper, various models are introduced to estimate the stiffness and strengths of such a sandwich structure, called K-Cor™, under out-of-plane compressive loading conditions. ince the reinforcing pins have a high modulus compared to the modulus of the facesheet in the transverse direction, the pins indent into the facesheets affecting the overall compressive stiffness of the sandwich structures. Models incorporating this interaction are constructed and their compressive properties are compared with experimental results for various sandwich specimens. The effect of pin locations and size of the sandwich on its compressive properties is also investigated. Nomenclature= Cross sectional area of facesheet = Cell spacing = Young's modulus of pin = Core stiffness = Modulus of facesheet = Stiffness of the sandwich structure = Core stiffness of infinite panel = Spring constant of model 2 = Spring constant of model 3 = Core thickness = Facesheet thickness = Thickness of the sandwich structure = Pin spring constant = Spring constant of core = Spring constant of facesheet = Spring constant of the sandwich structure = Interaction spring constant of a spring attached to a single pin = Interaction spring constant of the spring for entire core = Compressive spring constant of a single pin model = Number of active pins in the structures

Considering that the correct quantification of fatigue damage involves two load parameters, the available load ratio data on polymeric materials are analyzed. It is shown that crack growth can be characterized by two parameters, ΔK and K , without the need for any crack closure concept. The crack growth rates, starting from the threshold can be represented by the L-shaped curves in the ΔK-K plane defining two limiting variables, ΔK* and K *. Crack growth trajectory maps for various materials are developed by plotting ΔK* versus K *, as a function of crack growth rate. The trajectory defines the crack growth resistance curve providing a measure of material resistance to increasing crack tip driving forces.