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The conversion of furfuryl alcohol (FA) and selectivity towards dimers (C9-C10) and trimers (C14-C15) were investigated over molybdenum oxide (MoO3) catalyst. It was observed that FA conversion increased as an increase of reaction time. However, longer reaction time tended to limit the selectivity to dimers and trimers. Characterization data obtained from XRD, Raman, and XPS showed that after the reaction the terminal Mo O bond was elongated and the oxidation state was changed from Mo6+ to Mo5+. This was likely caused by the delocalization of extra electron to the Mo center during the activation of FA on MoO3 surface, instead of the formation of oxygen vacancy. After a proper regeneration process, the structure distortion caused by the elongation of Mo O bond was fully restored, however, the oxidation state were only restored to Mo5+/6+. Recyclability test using regenerated MoO3 indicates Mo5+/6+ can be as active as Mo6+.

Optical and photocatalytic properties were determined for the solid solution series (GaN)1–x(ZnO)x synthesized at high pressure over the entire compositional range (x = 0.07 to 0.9). We report for the first time photocatalytic H2 evolution activity from water for (GaN)1–x(ZnO)x without cocatalysts, pH modifiers and sacrificial reagents. Syntheses were carried out by reacting GaN and ZnO in appropriate amounts at temperatures ranging from 1150 to 1200 °C, and at a pressure of 1 GPa. ZnGa2O4 was observed as a second phase, with the amount decreasing from 12.8 wt% at x = 0.07 to ∼0.5 wt% at x = 0.9. The smallest band gap of 2.65 eV and the largest average photocatalytic H2 evolution rate of 2.31 μmol h−1 were observed at x = 0.51. Samples with x = 0.07, 0.24 and 0.76 have band gaps of 2.89 eV, 2.78 eV and 2.83 eV, and average hydrogen evolution rates of 1.8 μmol h−1, 0.55 μmol h−1 and 0.48 μmol h−1, respectively. The sample with x = 0.9 has a band gap of 2.82 eV, but did not evolve hydrogen. An extended photocatalytic test showed considerable reduction of activity over 20 hours.

Different structural phases (e.g., TT, T, and H) of niobium oxide were synthesized, characterized by XRD and Raman, and utilized for the furfuryl alcohol dehydration and condensation under mild conditions (100 °C and ambient pressure). Furfuryl alcohol conversion was dependent on reaction time and niobium oxide phase. Niobic acid and T/H phase transitional niobium oxide showed higher catalytic activity in comparison to a single crystalline phase niobium oxide. While T/H phase transitional niobium oxide showed higher conversion than that of niobic acid and TT phase niobium oxide, higher C 9 -C 15 products' selectivity (> 60%) was obtained with the latter catalysts.

Primary hyperparathyroidism (PHPT) due to parathyroid adenoma presenting as recurrent acute pancreatitis is a rare entity. A 17-year-old male presented with recurrent attacks of pancreatitis and was found to have elevated serum calcium and Parathyroid hormone levels, 11.9mg/dL (8.5-10.2 mg/dL) and 396 pg/ml (10-65pg/ml) respectively. USG neck showed a 1.1 x 0.9 cm hypoechoic nodule in the superior aspect of left thyroid lobe. Parathyroid scintigraphy findings were consistent with parathyroid adenoma. After recovery of pancreatitis, surgical excision of the adenoma was done and the histopathological findings confirmed parathyroid adenoma. There were no further recurrence of pancreatitis following the excision.Asian Journal of Medical Sciences Vol.8(1) 2017 98-100

Optical and photocatalytic properties were determined for the solid solution series (GaN)

We employed ab initio evolutionary algorithm USPEX to speed up the discovery of a novel oxynitride in the binary system of GaN-TiO2 using high-pressure synthesis. A 1:2 mixture of GaN and nanocrystalline TiO2 (anatase) was reacted under 1 GPa of pressure and at 1200 °C in a piston cylinder apparatus to produce a mixture of TiO2 (rutile) and an unknown phase. From the initial analysis of high resolution neutron and X-ray diffraction data, it is isomorphic with monoclinic V2GaO5 with a unit cell composition of Ga10Ti8O28N2 with the following parameters: monoclinic, space group C2/m, a = 17.823(1) Å, b = 2.9970(1) Å, c = 9.4205(5) Å, β = 98.446(3)°; Volume = 497.74(3) Å3. Further, a joint rietveld refinement revealed two distinct regimes—A Ti-rich block and a Ga-rich block. The Ti-rich block consists of four edge-shared octahedra and contains a site which is about 60% occupied by N; this site is bonded to four Ti. The remainder of the block consists of edge linked Ti-octahedral chains linked to the TiN/TiO fragments at octahedral corners partially occupied by nitrogen. The Ga-block contains two symmetry independent octahedral sites, occupied mostly by Ga, and a pure Ga-centered tetrahedral site bonded mostly to oxygen.