Mixed anionic double sodium-cobalt(II) diorthodiphosphate: structure and growing of single-crystals

The solubility of cobalt oxide was determined in the melts of the system Na2O–P2O5–CoO–NaF in a wide range of molar ratios Na2O:P2O5 (0.5–2.0) and temperatures of 800–9000C at the sodium fluoride content of 10 wt.% and 20 wt.%. The region of existence and optimal conditions for growing monocrystals of complex phosphate Na4Со3(PO4)2P2O7 in the melts of the system Na2O–P2O5–CoO–NaF was found out. The synthesized compound was investigated using a number of physicochemical methods (IR spectroscopy, diffuse reflection spectroscopy, X-ray phase analysis, X-ray structure analysis and differential thermal analysis). The complete chemical analysis of the synthesized compound was performed and the melting temperature was determined 7650С, without decomposition). The X-ray diffraction analysis of Na4Со3(PO4)2P2O7 single crystals was carried out and the unit lattice parameters were determined. Phosphate crystals belong to the rhombic crystal system, sp. gr. Pna21; crystal lattice parameters are as follows: a=18.021(1) Å, b=10.389(2) Å, c=6.532(2) Å, V=1222.47(1) Å3, Z=4, сcalc=3.47 g cm–3. The following specific features of the structure of complex phosphate Na4Со3(PO4)2P2O7 have been established: the presence of conduction channels for the sodium ion along the oy axis and the presence of differently coordinated Na and Co polyhedra with an uncharacteristic coordination number. The optimal conditions for the growth of complex phosphate single crystals with a high weight yield were selected. The use of the synthesized compound Na4Со3(PO4)2P2O7 as a functional material with ion conductivity was suggested.

Quantitative estimation of complex phosphate - solubilization by immobilized or free Azospirillum Lipoferum (H3) as vital vaccine in Pikovskaya broth (PVK) medium

Azospirillum species were collected from the rhizosphere and free soil of different plants in Al-Jabal El- Akhdar region. The isolates were identified according to biochemical activities. Isolate (H3) which showed the higher solubilization efficiency (SE) on Pikovskaya medium (PVK) containing insoluble phosphate (inorganic phosphate) Ca3(po4)2 Isolate (H3) was identified as Azospirillum lipoferum (H3), which used as an inoculum as free cell suspension or as alginate formulation. Phosphate solubilization was measured by A.lipoferum (H3) as free or alginate immobilized cells in (PVK) liquid medium and recording the pH of the medium at the same time. The results showed in the phosphorus content by immobilized bacteria in liquid (PVK) broth medium from 2nd day of incubation (2.48 µg/ ml) to 10th day (3.70 µg/ ml) and the free bacteria from 2nd day (8.81 µg/ ml) to 10th day (4.49 µg/ ml). pH of the liquid (PVK) broth medium was recorded from 2nd day to 10th day after incubation which decreased by immobilized A.lipoferum (H3) from 7.00 pH to 4.47 on the 10th day and by the free A.lipoferum (H3) to 6.00, which improved the production of organic acids from sugars which was response of decreasing the pH of the medium. This present study contribute to make agriculture more productive with less harm to the environment and for developing countries where the use of fertilizers is costly, and to encourage of using the biofertilizers ‘plant growth promoting rhizobacteria’ (PGPR) instead of the chemical fertilizers to enhance the plant growth which is the main goal to increase the food production in a healthy way.

Preparation and crystal structure of K2Ce(PO4)2: a new complex phosphate of Ce(iv) having structure with one-dimensional channels

Synthesis and crystal structure of K2Ce(PO4)2, which is a new complex phosphate with Ce4+.