[en] A process for extracting uranium from a crude wet process phosphoric acid containing uranium is claimed. The process comprises treating the crude acid, which contains 35-60% by weight of P₂O₅ and uranium, at least some of which is in the hexavalent state, with a solution in an inert non polar water immiscible organic solvent of a neutral phosphorus compound and in the presence of nitrate ion to form an organic extract containing uranium and an aqueous phosphoric acid

[en] Highlights: • Pristine BP with ten layers or more possesses a strong stability. • The stability of pure BP is dependent on the native phosphorus oxide. • The plasma-induced phosphorus oxide is not dense enough. • The density of the oxide layer plays a vital role in the stability of BP. It has been a long-standing challenge to produce air-stable few-layer black phosphorus (BP) because BP degrade rapidly in ambient atmosphere. Here we demonstrate that the pristine BP with ten layers or more possesses a strong stability and can be stored in air for two weeks. The physical mechanism can be ascribed to the native phosphorus oxide formed on the surface, which act as a stable and protective capping layer and prevent the underlying layer from further oxidation. The pristine 10-layer BP FET device can maintain a high mobility value of around 220 cm² V^-1s⁻¹ in air for 2 weeks. By contrast, the plasma-induced phosphorus oxide is not dense or robust enough to protect the underlying sample from oxidation. These results suggest that the density of the oxide layer on the surface plays a vital role in the stability of BP flakes. This work offers new perspectives for probing the stability of BP based electronic and optoelectronic devices.

[en] The change of the viscoelastic flow near the imprinting temperature was analyzed by a penetration method with a commercial TMA and the result was compared with thermally-imprinted SnO-P₂O₅ (SP) and SnO-B₂O₃-P₂O₅ (SBP) glass samples by an imprint apparatus. The viscosity of SP glass increases monotonically with increasing SnO content and the specific movement is shown in viscoelastic flow under the optimized thermal imprinting temperature for SP glasses.

[en] The influence of several ions in the flotation of phosphorus - uraniferous ore from Itataia were evaluated. Testing with distillated water, water from Itataia region and water prepared in laboratory by nitrate ion addition were done. (E.G.)

[en] Highlights: • Perennial forb or grass had higher stability than legume or annual and biennial. • High N and P increased annual and biennial dominance, but decreased its stability. • Diversity decline negatively affected community stability only in annual grassland. • Functional group shift was the main driver of perennial grassland stability. Exogenous fertilization could efficiently improve grassland productivity and promote grassland restoration. Increasing fertilization may profoundly affect community stability, whereas the underlying compensatory dynamics among functional groups in regulating grassland stability remain unclear. Three different grasslands, annuals forb (AF) community, perennial grass (PG) community and perennial forb (PF) community, on semiarid Loess Plateau were selected. We designed a 3-year split-plot experiment (main-plot: 0, 25, 50, and 100 kg N ha⁻¹ yr⁻¹; subplot: 0, 20, 40 and 80 kg P₂O₅ ha⁻¹ yr⁻¹) to explore how N and P addition affects community stability and its relationship with species richness, species asynchrony and functional group stability. Temporal stability differed largely between functional groups under N and P addition, perennial forbs or grasses had higher stability than perennial legumes or annuals and biennials. Decreased stability of PG and PF communities was primarily due to reduced species asynchrony under N addition alone, while it attributed to increased dominance of perennial legumes after P addition alone. 50 and 100 kg N ha⁻¹ yr⁻¹ combined with P addition significantly increased dominance of annuals and biennials, but decreased stability of annuals and biennials, which caused significant declines in stability of the three communities. Significant species richness decline induced by N and P addition only occurred in AF community, which suppressed AF community stability through reducing species asynchrony. AF community stability was regulated by additively negative effect of diversity decline and decreased annuals and biennials stability. Whereas, in PG and PF communities, nutrient-induced changes of functional groups stability were the main driver of community stability rather than diversity. Our study highlights the role of functional group composition and dynamics in regulating the effects of diversity on community stability and rational N and P combined addition was essential for conserving stability of different grasslands on semiarid Loess Plateau.

[en] Short communication

[en] We present the effect of P₂O₅ addition on barium calcium aluminum borosilicate BCABS glasses of composition (mol %) 35BaO-15CaO-5Al₂O₃-(37-x)SiO₂-8B₂O₃-xP₂O₅ (0≤x≤5). The incorporation of P₂O₅ increased network polymerization and crystallization tendency. However, addition of P₂O₅ leads to the formation of Cr₂O₃ at the interface, saturating it in the ions of the metal. This improves glass-to-metal bonding. (author)

[en] Lithium disilicate glass-ceramics derived from the SiO₂-Li₂O-K₂O-Al₂O₃-ZrO₂-P₂O₅ system with different P₂O₅ content (from 0.5 mol.% to 2.0 mol.% at a step of 0.5 mol.%) were prepared for dental restorative application. Flexural strength of final glass-ceramics and translucent characteristics expressed in term of contrast ratio (CR) were measured. The interrelations between P₂O₅ content, microstructure and properties were discussed. Glass-ceramic with a P₂O₅ content of 1.0 mol.%, in which elongated rod-like Li₂Si₂O₅ crystals formed an interlocking microstructure, showed the highest flexural strength and suitable contrast ratio for dental restorative application.

[en] Results are cited of laboratory research into the possibility of radiometric determination of P₂O₅ in phosphorites of Polpinsky deposit. On the basis of the studies performed, a plant and methods have been developed for the continuous control of P₂O₅ content in ore. The plant has been tested at the Bryansk phosphorite works. The accuracy of analysis is 0.8 percent

[en] We evaluated the effect of nicotinamide on cellular O₂ consumption and metabolic status i.e., adenylate phosphates and NAD+ in-vitro, and changes in blood flow in-vivo, to determine whether changes in cellular metabolism or increased oxygen availability, was responsible for increased tumor oxygenation. Thirty min. Pre-incubation of cells with ∼ 4mM (=500mg/kg) nicotinamide resulted in no change in cellular O₂consumption. Similarly, neither the adenylate phosphates nor the cellular NAD+ levels were altered in the presence of ∼ 4mM nicotinamide. In-vivo, nicotinamide (500mg/kg) increased O₂ availability as estimated by changes in relative tumor blood flow (RBC flux). The changes in RBC flux measured by the laser Doppler method, were tumor volume dependent and increased from ∼ 35% in ∼ 150mm³tumors to ∼ 75% in ∼ 500mm³ tumors. In conclusion, these observations indicate a reduction in local tissue O₂ consumption is not a mechanism of improved tumor oxygenation by nicotinamide in Fsa II murine tumor model. The primary mechanism of increased pO₂ appears to be an increased local tumor blood flow