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For the elucidation of the mechanism of calcium phosphate formation on commercially pure titanium (CP Ti) in the human body, rutile TiO2 single crystal plates with (001), (110), and (111) facets, n...

In this work, ultrathin nanosheet-assembled, phosphate ion-functionalized NiO (P-NiO) microspheres were prepared via a facile hydrothermal reaction and subsequent thermal annealing. The formation m...

Phase transition of crystals is one of the most important topics in condensed matter physics, chemistry, and materials sciences in which the basic physical and chemical properties of the crystals t...

We describe the design, synthesis, and characterization of a chiral hexacoordinated phosphate ion that features an octahedral P(V) core consisting of two N,N,O-tridentate backbones. We further demonstrate that the corresponding hydrogen phosphate acts as an effective catalyst for a highly enantioselective Pictet-Spengler-type reaction, wherein the relationship between the structure of the chiral phosphate ion and its ability to dictate the absolute stereochemistry is revealed in conjunction with precise structural elucidation of the phosphate ion.

Hydroxyapatite is an inorganic mineral closely resembling the mineral phase in bone. However, as a biological mineral, it is highly disordered, and its composition and atomistic structure remain poorly understood. Here, synchrotron X-ray total scattering and pair distribution function analysis methods provide insight into the nature of atomistic disorder in a synthetic bone mineral analogue, chemically substituted hydroxyapatite. By varying the effective hydrolysis rate and/or carbonate concentration during growth of the mineral, compounds with varied degrees of paracrystallinity are prepared. From advanced simulations constrained by the experimental pair distribution function and density functional theory, the paracrystalline disorder prevalent in these materials appears to result from accommodation of carbonate in the lattice through random displacement of the phosphate groups. Though many substitution modalities are likely to occur in concert, the most predominant substitution places carbonate into the mirror plane of an ideal phosphate site. Understanding the mineralogical imperfections of a biologically analogous hydroxyapatite is important not only to potential bone grafting applications but also to biological mineralization processes themselves.

The tetrakisquinoline ligand HT(6-MeO8Q)HPN (N,N,N′,N′-tetrakis(6-methoxy-8-quinolylmethyl)-2-hydroxy-1,3-propanediamine) exhibited Zn2+-induced fluorescence enhancement with high specificity and sensitivity (IZn/I0 = 57 and ICd/IZn = 6% in the presence of 2 equiv of Zn2+; LOD (limit of detection) = 15 nM). This ligand also exhibited fluorescence enhancement specific to inorganic phosphate (PO43–) in DMF–HEPES buffer (50 mM HEPES, 100 mM KCl, pH = 7.5) (1:1) in the presence of 2 equiv of Zn2+. The structure of the unprecedented tetranuclear zinc complex with a μ4-PO4 bridge was elucidated by X-ray crystallography as the key species responsible for fluorescence enhancement.

Here, we demonstrate an effective strategy to constitutionally increase the conductivity and electrocatalytic property of NiFe

Earlier work leading to the standard potential of the Ag/AgCl electrode in 20 and 50 mass% 1-propanol/water solvents at temperatures ranging from 37 to −10°C has been extended to study the dissociation constants of the primary phosphate ion (H 2 PO 4 − ) in the same media at this temperature range

Le phosphate est reduit en phosphine par le borohydrure de sodium dans des conditions seches. Limite de detection 0,1 ng de phosphate avec un detecteur a photometrie de flamme

Utilisation de la theorie de perturbation mecanique statistique et d'une simulation par ordinateur de la dynamique moleculaire pour obtenir les potentiels de force moyenne du systeme sodium-dimethylphsphate. Presentation des resultas des potentiels de force moyenne pour deux types de geometrie intermoelculaire

The ultraviolet induced photodecomposition of ammonium oxalate has been studied. The rate-time plots show an initial deceleration region which leads to a final constant value. The intensity dependence of the photorate can be represented by an equation of the type R = AI + BP. The photolysis was found to be sensitized by precompression and desensitized by ageing. Similarly the photolytic rate of ammonium oxalate crystallized from solutions containing phosphate ion and chloride ion impurity showed a sensitization and desensitization, respectively.

Polarographic data are obtained for three niobium-citrate complexes and one niobium-EDTA complex. EDTA medium is not considered suitable for determination of Nb, but the use of strong citric acid medium at pH 3 yields reproducible results. Niobium is polarographically determined in the presence of phosphate ion, Ta, Mo, and Tl. (auth)

In this experiment the cell glass electrode | aqueous solution in 0.01 M NaCl | AgCl; Ag is used for the direct determination of the acidity function.