Studies on interstitial carbon doping from a Ti precursor in a hierarchical TiO2 nanostructured photoanode by a single step hydrothermal route.

Carbon doping from a Ti precursor in TiO2 synthesized by a hydrothermal method was studied. The structural, optical and morphological study of the deposited material was carried out using X-ray diffraction, UV-vis spectroscopy and scanning electron microscopy characterization techniques. The elemental composition of the TiO2 deposited with different precursor concentrations was studied using X-ray photoelectron spectroscopy and electron dispersive X-ray spectroscopy. The amount of elemental carbon in the TiO2 matrix is found to be increased as the Ti precursor concentration is increased, which strengthens the proposed idea of carbon doping via a Ti precursor.

Studies on effect of temperature on synthesis of hierarchical TiO2 nanostructures by surfactant free single step hydrothermal route and its photoelectrochemical characterizations.

Exotic hierarchical rutile TiO2 nanostructures are synthesized by surfactant free single step hydrothermal route. The effect of reaction temperature, ranging from 140°C to 200°C on the properties of the synthesized rutile-TiO2 is investigated. The synthesized rutile-TiO2 nanostructures are characterized using X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, UV-vis spectroscopy and scanning electron microscopy techniques. The deposited TiO2 samples are found to be photoelectrochemically active and the best photoelectrochemical performance (0.95±0.05%) is obtained for the sample deposited at 180°C. A possible temperature dependent growth mechanism resulting in photochemically active TiO2 nanostructure thin films is proposed.

Clinical profile of non-O1 strain-O139 of Vibrio cholerae in the region of Ambajogai, Maharashtra.

OBJECTIVES: To study clinical profile of the newly emerged novel strain non-O1, O139 of Vibrio cholerae, in the region of Ambajogai, District Beed of Maharashtra. METHODS: Out of 208 patients of acute gastroenteritis, 41 revealed to be positive for Vibrio cholerae by recommended method of stool examination. All the strains were sent to National Institute of Cholera and Infectious Diseases, Calcutta for confirmation. RESULTS: Out of 41 cases, 12 were of Vibrio cholerae O1, 29 Non-O1, of which nine found to be O139 strain. All patients were from 2-80 years of age with low-socioeconomic status and maximum incidence was in August (64.70%), presented with severe rice watery loose motions. Vomiting was observed in 26 (63.41%), more so in patients of O139 infection (88.88%) than four (33.33%) of O1 infection. Sweating was observed in three patients (33.33%) of O139 infection, cramps in gastrocnemis muscles in three patients (33.33%) of O139 infection and two (16.66%) of O1 infection. Signs of dehydration were mild to moderate in four patients (33.33%) of O1 infection; severe dehydration in six (66.66%), moderate in two (22.22%) and mild in one patient (11.11%) of O139 infection. While dehydration was severe in four (20%), moderate in one (5%) and mild in three patients (15%) of Non-O1 infection (excluding O139 cases). Clinical features were more severe in patients of serotype O139 than the patients of O1 and Non-O1 (excluding O139 cases). However all patients responded to intravenous fluids, oral rehydration and antibiotics (tetracycline) within 24-48 hours without any mortality. CONCLUSIONS: This study reflects the first emergence of Non-O1, strain O139 during the year 1997 with severe and critical clinical features in Ambajogai region causing high morbidity in the form of severe dehydration and peripheral circulatory collapse which requires early and correct diagnosis and prompt treatment.