Calcium-deficient apatitic (cd-HA) crystals with core-shell nanostructure with needlelike shape, 5-10nm in diameter and 20-80nm in length, were prepared via an in situ formation in the presence of polyacrylic acid (PAA) under aqueous solution of different pH values, ranging from 9 to 11. Nanostructure of the resulting crystals showing a core-shell configuration with a thin layer of PAA shell of...

The problem of crystal sizes is one of the central problems of differentiation of a terrestrial magma ocean and it has been an arbitrary parameter in previous models. The crystal sizes are controlled by kinetics of nucleation and crystal growth in a convective magma ocean. In contrast with crystallization in magma chambers, volcanic lavas, dikes, and other relatively well studied systems, nucle...

Ice-templating techniques, including freeze-drying and freeze casting, are extremely versatile and can be used with a variety of materials systems. The process relies on the freezing of a water based solution. During freezing, ice nucleates within the solution and concentrates the solute in the regions between the growing crystals. Once the ice is removed via sublimation, the solute remains in ...

Potassium tetraborate tetrahydrate (KTBTH) single crystals were grown by slow evaporation solution growth method at room temperature. The grown crystal was characterized by single crystal X ray diffraction analysis. FT – IR and FT – Raman spectra were recorded to identify the functional groups. Optical transmission and absorption spectral studies were carried out to test the transmittance of th...

Antifreeze proteins (AFPs) are a subset of ice-binding proteins that control ice crystal growth. They have potential for the cryopreservation of cells, tissues, and organs, as well as for production and storage of food and protection of crops from frost. However, the detailed mechanism of action of AFPs is still unclear. Specifically, there is controversy regarding reversibility of binding of A...

well-defined crystalline pbse nanocubes and nanospheres have been synthesized through a simple hydrothermal method by using pb2+- edta and pb2+- oleylamine complexes at 180°c for different reaction times. composition and morphology of the samples have been characterized by means of xrd and sem. gradual release process of pb2+ from pb2+-edta and pb2+-oleylamine complexes can adjust the growth ra...

Equations are presented that model diffusion of a protein to the surface of a growing crystal in a convection-free environment. The equations apply to crystal growth solutions that contain both a protein and a protein precipitant. The solutions are assumed ternary and the equations include all four diffusion coefficients necessary for the full description of the diffusion process. The four diff...

Nucleation parameters such as surface energy per unit area, energy per unit volume, radius of critical nucleus, critical free energy barrier, number of molecules in the critical nucleus and nucleation rate have been evaluated for L-arginine maleate dihydrate single crystals. The theoretical predictions of optimized growth conditions were confirmed by growing the crystal using solution growth te...

It has been observed that sugar crystals growing in solution exhibit growth rate dispersion, that is, variation in growth rate from one crystal to the next. We consider the problem of estimating the distribution of growth rates in batch-grown crystals, given only samples of their sizes at a number of fixed points in time. The problem can be expressed as a tomographic image reconstruction proble...