Calcium crystal

Gogolewski et al. " combined Pluronic F-68(poly(ethylene-propylene-ethylene oxide) with PCL within the same soft segment. BD or 2-amino-l-butanol was used as the chain extender and HDI as the hard segment. They observed that all the materials calcified and calcification increased with material hydrophilicity. The stmcture and composition of the calcium crystals formed on the materials depended on the PU chemistry. 

Carr, G., Simmons, N.L., and J.A. Sayer, 2006, Disruption of clc-5 leads to a redistribution of annexin A2 and promotes calcium crystal agglomeration in collecting duct epithelial cells. Cell Mol Life Sci. 63(3) 367-77. 

When the equilibrium mixture is permitted to cool rapidly, the heavier salt phase settles and solidifies, thus leaving the lighter metal phase on top as a liquid. Inasmuch as calcium metal starts to precipitate and settle before the solidification point of the salt phase is reached, some of the calcium is trapped in the salt phase and, together with the calcium which is dissolved by the molten salt, is not recovered in the following synthesis. Once the sodium chloride-calcium chloride layer has solidified, however, the precipitating calcium remains trapped in the metal layer. When the metal layer freezes, its composition consists of calcium crystals embedded in a sodium matrix which may be removed by preferential reaction with a lower alcohol.9... 

Calcium crystallizes from sodium solution in flat platelets that have a beautiful, although irregular, dendritic structure. The particle size depends on the rate of cooling, but under ordinary circumstances varies between about 0.01 and 2.0 mm. The apparent density of the isolated powder is about 0.5. Its finely divided nature enhances its reactivity in most of the reactions wherein it is used. 

A sodium-calcium mixture collects at the cathode, but the solubility of calcium in sodium decreases with decreasing temperatures so that the heavier calcium crystals, which form as the mixture is cooled, settle back into the bath. The crude sodium is filtered at 105 to 110°C, giving sodium of 99.9% purity that is run molten into a nitrogen-filled tank car and allowed to solidify. 

If the calcium phosphate fibers grown from ultraphosphate melts are slurried with a solution of sodium ethylene diamine tartaric acid the calcium crystals can be converted to a sodium phosphate glass that dissolves very slowly yielding very long chains. 

Calcium crystallizes with a body-centered cubic structure. 

The sandfish (Scincus scincus) can be cited as a further example whose characteristics could one day be implemented in textile fagades. The skin of this reptile, hving in the deserts of North Africa, is insensitive to abrasion, which results from the surface structure. It is equipped with tiny minerals, e.g. silicon or calcium crystals, embedded in the keratin. The minerals are arranged wavelike at very small distances apart. Contact with the ground always happens to be by these minerals [33, p. 166]. By implementing this functional principle in architecture, the life expectancy of exterior elements such as fagade systems could be considerably increased. 

Calcification involves the seeding of the calcium apatite crystal and the growth of the crystals. It would be more convenient to review the second of these mechanisms first. This can best be done by assuming for the moment that the bone matrix, connective or cartilaginous, is bathed in a medium supersaturated in calcium phosphate. Intrinsic to the matrix, there is a mechanism that precipitates calcium phosphate in the form of tiny apatite crystals. If there is no interference with the process of calcification, either by deficient absorption of calcium (vitamin D deficiency) or by active dissolution of the calcium crystals (parathormone), most of the process of mineralization can probably be explained by the physicochemical properties of the apatite crystals. Thus, the divalent cations and anions, PO4 and calcium, penetrate the hydration shell reaching the surface of the crystals where they are crystallized, thereby increasing the size of the crystals. As mineralization proceeds, the amount of bound... 

Mammalian organisms, including humans, have learned to deal with solutes by maintaining them in various levels of solubility. Thus, calcium crystallizes to form calcium apatite in a very organized fashion to build bones. Lipid molecules of the cell membranes exist in a fluid crystal structure and play a key role in their properties. 

Carbasalate calcium is irritating to the gastric mucosa. Therefore, it cannot be administered in capsules. It is administered as single-dose powders in sachets instead. The powders should be dissolved in a glass of water before ingestion. When carbasalate calcium powders are prepared in a pharmacy, the poor flow properties of the active substance may result in a relatively low uniformity of mass. The poor flow of the powder is probably due to an irregular shape of the carbasalate calcium crystals and perhaps also to a relatively wide size distribution of the raw material. 

How would a particulate-level illustration differ if you were to draw a calcium crystal instead of a potassium crystal ... 

Muhammad A F, Micko M M 1984 Accumulation of calcium crystals in the decayed wood of aspen attacked by Pomes ignarious. lAWA Bull 5 237-241... 

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