information about forms of phosphorus (p) is important for the evaluation of p status in soil and also understanding of the soil fertility and plant nutrition. to obtain such information and to determine the relationship between the p forms from soil characteristics, amount of different organic and inorganic p forms of 20 soil composite samples of eastern azerbaijan province, iran were determin...

Recent experimental evidence suggests that octacalcium phosphate (OCP) is a necessary precursor to hydroxyapaptite in the amorphous-crystalline transformation that occurs after the spon..: taneous precipitation of calcium phosphate in the pH range 7.00-9.25. The transformation appears to occur by heterogeneous nucleation of OCP by the initially formed amorphous calcium phosphate (ACP) phase. AC...

This study aimed at preparing and studying the properties of nanoparticles of calcium phosphate (nCaP) with Ca/P ratios ranging from 1.0 to 1.67 using a spray-drying technique. Micro-structural analyses suggested that the nCaPs with Ca/P ratios of 1.67 to 1.33 were nano-sized amorphous calcium phosphate (ACP) containing varying amounts of acid phosphate and carbonate. The nCaP with Ca/P ratio o...

The driving force and nucleation rate of calcium phosphate (Ca-P) precipitation in simulated body fluid (SBF) were analyzed based on the classical crystallization theory. SBF supersaturation with respect to hydroxyapatite (HA), octacalcium phosphate (OCP) and dicalcium phosphate (DCPD) was carefully calculated, considering all the association/dissociation reactions of related ion groups in SBF....

Formation of hydroxylapatite through the precipitation and evolution of calcium phosphate precursor phases under varying conditions of temperature (25–90 °C), pH (6.5–9.0), and calcium to phosphorus ratio (1.0, 1.33, 1.5, and 1.67) comparable to those found in many sediments and soils were studied. The products of low-temperature precipitation were analyzed by ex situ X-ray diffraction and SEM,...

We investigate O’Raifeartaigh-type models for F-term supersymmetry breaking in gauge mediation scenarios in the presence of gravity. It is pointed out that the vacuum structure of those models is such that in metastable vacua gravity mediation contribution to scalar masses is always suppressed to the level below 1 percent, almost sufficient for avoiding FCNC problem. Close to that limit, gravit...

Calcium phosphate precipitation obtained from aqueous solutions at room and body temperature and pH 5.5-7.5 were investigated by high-resolution transmission electron microscopy (HRTEM), transmission electron diffraction, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Supersaturated solutions of calcium phosphates were prepared by different methods of mixing of the stock soluti...

The surfaces of hydoxyapatite ceramics were modified by the precipitation of octacalcium phosphate coating from aqueous solution and the biomimetic method synthesized nanohydroxyapatite coatings. Both coatings were deposited as continuous and uniform layers. It was demonstrated that the octacalcium phosphate coating was inappropriate for in-vitro osteoblast proliferation despite of good initial...

It was demonstrated that octacalcium phosphate collagen composite achieved notable bone regeneration in bone defects in preclinical studies. On the basis of the research results, an investigator-initiated exploratory clinical trial was conducted after approval from a local Institutional Review Board. This clinical study was performed as a single-arm non-randomized intervention study. Octacalciu...