A semi-batch crystallization system is used to determine growth kinetics and morphology of barium carbonate crystals, under a constant pH value and constant temperature in the various relative supersaturations. Results show that crystal growth rate satisfies a first-order kinetic expression at high relative supersaturation, while at relative supersaturation values lower than 3,  the k...

A new method is described for studying reproducibly, the kinetics of crystallization of calcium fluoride under conditions of constant solution composition. The method can be used even at very low supersaturation. The rate is proportional to the square of the supersaturation, over the range of relative supersaturation, S = 0.20 1.66. The results point to a surface controlled crystallization. The...

High-quality protein crystals of suitable size are an important prerequisite for applying X-ray crystallography to determine the 3-dimensional structure of proteins. However, it is often difficult to obtain protein crystals of appropriate size and quality because nucleation and growth processes can be unsuccessful. Here, we show that by adsorbing proteins onto porous polystyrene-divinylbenzene ...

Solubility of UO(3) x nH(2)O and sorption of U(VI) onto ferric (hydr)oxides were measured at pH 5.9, 6.8, and 7.8 at 10(-3.5)atm CO(2) using reaction times up to 48 days. Precipitation was fastest in the presence of hydrous ferric oxide and slower with hematite or without an initial solid phase. Solubility after 48 days was statistically similar for low to intermediate initial supersaturation c...

The mechanism of the formation of a self-aligned hydroxyapatite (HAP) nanocrystallite structure was examined. It is found that the highly ordered HAP nanocrystallite assembly is attributed to the so-called self-(homo)epitaxial nucleation and growth. On the other hand, according to this mechanism, a high supersaturation will give rise to a random assembly of HAP crystallites. The effects of ions...

Potassium citrate is prescribed to decrease stone recurrence in patients with calcium nephrolithiasis. Citrate binds intestinal and urine calcium and increases urine pH. Citrate, metabolized to bicarbonate, should decrease calcium excretion by reducing bone resorption and increasing renal calcium reabsorption. However, citrate binding to intestinal calcium may increase absorption and renal excr...

In this study, amorphous solid dispersions containing dutasteride and various excipients, manufactured by spray-drying processes, were characterized to determine the effects on their ability to form supersaturated solutions and to identify the effects of supersaturation on increasing the bioavailability of dutasteride. The excipients included Eudragit E, hydroxypropyl-β-cyclodextrin (HP-β-CD), ...

The circadian rhythm of the urinary saturation of uric acid, sodium acid urate, and ammonium acid urate was studied in 5 normal healthy male volunteers before and during 5 days of treatment with sodium-potassium citrate (1 g t.i.d., 1 g q.i.d., or 3 g t.i.d.). Urinary saturation was estimated on the relative supersaturation scale of Marshall and Robertson. Uric acid relative supersaturation var...

At fast rotation rates, the coronal activity of Gand K-type stars has been observed to ‘saturate’ and then decline again at even faster rotation rates – a phenomenon dubbed ‘supersaturation’. In this paper, we investigate coronal activity in fast-rotating M-dwarfs using deep XMM–Newton observations of 97 low-mass stars of known rotation period in the young open cluster NGC 2547 and combine thes...

eries, water in egg-hatching or fry-rearing tanks may have a condition called “gas supersaturation” that is harmful to fish. Gas supersaturation means that the water contains more gas at a certain air (barometric) pressure and water temperature than would normally occur if the water was allowed to come to equilibrium with the atmosphere. Fish living in such waters may develop a stressful or let...