Preparation of a Resorbable Osteoinductive Tricalcium Phosphate Ceramic

Over the past decade we have demonstrated numerous times that calcium phosphates can be rendered with osteoinductive properties by introducing specific surface microstructures1. Since most of these calcium phosphates contained hydroxyapatite, they are either slowly or not resorbable2. Resorbability is an often sought after characteristic of calcium phosphates so that they can be gradually replaced by newly formed bone. The objective of this study was to prepare a resorbable surface microstructured tricalcium phosphate (TCP) ceramic and evaluate its osteoinductive property and resorption rate after intramuscular implantation in dogs. This material was then compared to the established and slowly resorbable osteoinductive biphasic calcium phosphate ceramic (BCP)

Adsorbent phosphates

An adsorbent which uses as its primary ingredient phosphoric acid salts of zirconium or titanium is presented. Production methods are discussed and several examples are detailed. Measurements of separating characteristics of some gases using the salts are given

Phytic acid degradation by phytase – as viewed by 31P NMR and multivariate curve resolution

The 31P NMR method is a most direct and useful method to describe the degradation of phytic acid to lower inositol phosphates by the action of the enzyme phytase. The use of chemometric and CARS visualizes and helps in the interpretation of the results. By means of LatentiX it has been possible to visualize the time-dependent hydrolysis of phytic acid and by PCA the complexity of the phytic acid is shown in the score plots. By modeling the spectra in CARS it is possible to identify and quantify each of the inositol phosphates

Soil bacteria and phosphates

Cover title.Includes bibliographical references

Assessment of in situ immobilization of Lead (Pb) and Arsenic (As) in contaminated soils with phosphate and iron: solubility and bioaccessibility

The effect of in situ immobilization of lead (Pb) and arsenic (As) in soil with respectively phosphate and iron is well recognized. However, studies on combined Pb and As-contaminated soil are fewer, and assessment of the effectiveness of the immobilization on mobility and bioaccessibility is also necessary. In this study, a Pb and As-contaminated soil was collected from an abandoned lead/zinc mine in Shaoxing, Zhejiang province of China, which has been treated with three phosphates, i.e., calcium magnesium phosphate (CMP), phosphate rock, and single super-phosphate (SSP) for 6 months in a field study. The ferrous sulfate (FeSO4) at 20 g kg-1 was then amended to the soil samples and incubated for 8 weeks in a greenhouse. The solubility and bioaccessibility tests were used to assess the effectiveness of the in situ immobilization. The result showed that phosphates addition decreased the concentrations of CaCl2-extractable Pb; however, the concentrations of water-soluble As increased upon CMP and SSP addition. With the iron addition, the water-soluble As concentrations decreased significantly, but CaCl2-extractable Pb concentrations increased. The bioaccessibility of As and Pb measured in artificial gastric and small intestinal solutions decreased with phosphate and iron application except for the bioaccessibility of As in the gastric phase with SSP addition. Combined application of phosphates and iron can be an effective approach to lower bioaccessibility of As and Pb, but has opposing effects on mobility of As and Pb in contaminated soil

I-Xe analysis of a magnetic separate from Lodranite GRA95209

I-Xe dating of a magnetic mineral separate from lodranite GRA95209 suggests that peak temperatures (and therefore melt migration) occurred early, at least a few million years before closure of the I-Xe system in phosphates from Acapulco

The Mineralogy, Geochemistry and Phosphate Paragenesis of the Palermo #2 Pegmatite, North Groton, New Hampshire

An investigation of the beryl-phosphate subtype Palermo #2 pegmatite, located in the Grafton pegmatite field of New Hampshire, has revealed a large number of phosphate species. Late-stage, carbonate-bearing aqueous fluids have metasomatically altered primary phosphates producing a suite of nearly forty species of secondary phosphates. The secondary phosphates at Palermo #2 are a result of alteration of primary phosphates and associated silicate, carbonate, sulfide, arsenide and oxide minerals locally present in the core margin. Concomitant alteration of these associated minerals contributes the necessary ions to the hydrothermal fluids responsible for the formation of the diverse suite of secondary phosphates. Alteration of the mineral assemblage occurring in a given area creates a collection of secondary phosphates characteristic of that specific assemblage, whereas a completely different collection of secondary phosphates may appear only a few centimeters away. Thus, each suite of secondary phosphates is the product of its specific microenvironment of alteration

The Mineralogy, Geochemistry and Phosphate Paragenesis of the Palermo #2 Pegmatite, North Groton, New Hampshire

An investigation of the beryl-phosphate subtype Palermo #2 pegmatite, located in the Grafton pegmatite field of New Hampshire, has revealed a large number of phosphate species. Late-stage, carbonate-bearing aqueous fluids have metasomatically altered primary phosphates producing a suite of nearly forty species of secondary phosphates. The secondary phosphates at Palermo #2 are a result of alteration of primary phosphates and associated silicate, carbonate, sulfide, arsenide and oxide minerals locally present in the core margin. Concomitant alteration of these associated minerals contributes the necessary ions to the hydrothermal fluids responsible for the formation of the diverse suite of secondary phosphates. Alteration of the mineral assemblage occurring in a given area creates a collection of secondary phosphates characteristic of that specific assemblage, whereas a completely different collection of secondary phosphates may appear only a few centimeters away. Thus, each suite of secondary phosphates is the product of its specific microenvironment of alteration

The Effects Of Triphenylphosphate and Recorcinolbis(Diphenylphosphate) on the Thermal Degradation Of Polycarbonate in Air

The thermal degradation of polycarbonate/triphenylphosphate (PC/TPP) and PC/resocinolbis(diphenylphosphate) (PC/RDP) in air has been studied using TGA/FTIR and GC/MS. In PC/phosphate blends, the phosphate stabilizes the carbonate group of polycarbonate from alcoholysis between the alcohol products of polycarbonate degradation and the carbonate linkage. Thus, the evolution of bisphenol A, which is mainly produced via hydrolysis/alcoholysis of the carbonate linkage, is significantly reduced, while, the evolution of various alkylphenols and diarylcarbonates increases. The bonds that are broken first in the thermal degradation of both the carbonate and isopropylidene linkages of polycarbonate are the weakest bonds in each, when a phosphate is present. Triphenylphosphate and resocinolbis(diphenyl-phosphate), even though they exhibit a significant difference in their volatilization temperature, appear to play a similar role in the degradation pathway of polycarbonate