7 research outputs found
Notes on the presence of Phrynarachne ceylonica (O. Pickard-Cambridge, 1884) from the Andaman and Nicobar Islands
Description of Phrynarachne ceylonica (O. Pickard-Cambridge, 1884) female from Andaman and Nicobar islands after a long gap of 124 years has been provided through the collections of fresh specimen in and around these islands. The selection of habitat and the range expansion are discussed. The distribution records of the species are mapped
New distributional report of Borboropactus bituberculatus Simon 1884 from Nicobar Islands, India
A female of Borboropactus bituberculatus Simon, 1884 has been reported from Andaman and Nicobar Islands, India for the first time. Diagnostic characters are provided for the species, as well as new photographs or illustrations of the genital organs of the species
Influence of synthesis temperature on the growth and surface morphology of Co3O4 nanocubes for supercapacitor applications
A facile hydrothermal route to control the crystal growth on the synthesis of Co3O4 nanostructures with cube-like morphologies has been reported and tested its suitability for supercapacitor applications. The chemical composition and morphologies of the as-prepared Co3O4 nanoparticles were extensively characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Varying the temperature caused considerable changes in the morphology, the electrochemical performance increased with rising temperature, and the redox reactions become more reversible. The results showed that the Co3O4 synthesized at a higher temperature (180 °C) demonstrated a high specific capacitance of 833 F/g. This is attributed to the optimal temperature and the controlled growth of nanocubes
Pathway of sucrose oxidation in manganese (Pyrolusite) nodule
Polymetallic sea nodules are the potential resources of copper, cobalt, manganese, and nickel. The exploration and exploitation of manganese nodules are necessary to meet the future demands of Mn in the world. This work describes the valuable extraction of Mn through an innovative approach of using sucrose as a reductant. The metal extraction from the nodule leaching was studied in ambient temperature (27 °C) and at an elevated temperature 90 °C with and without agitation. In both cases, 99.9% of Mn was extracted while the extraction time appears to be significantly low (2 h) at 90 °C but it requires a longer time of 24 h at 27 °C. The optimum sucrose concentration selected was 7% (w/w) of nodule for maximum metal extraction. With use of 10% (v/v) H2SO4, 7% (w/w) sucrose at 90 °C, and solid to liquid (S/L) ratio of 1:10 the achieved metal recovery figures were the following: Mn >99%, Ni 98%, Cu 87%, Co 83% in 2 h. The oxidation pathway of sucrose is outlined in this study with the aid of mass spectrometry during reductive leaching of ocean bed nodule. Sucrose in acidic environment generates 1- or 6-monoacid of sucrose with ions of m/z (mass-to-charge ratio) 355 and 127, 5-hydroxymethylfurfural (5HMF). A dehydrated glucose complex (m/z 325) was generated at elevated temperature. These released organics act as reductant for the leaching of Mn2+ from MnO2. Glucaric acid (m/z 211) is generated as the end product of the sucrose oxidation in the solution
Measurement of the branching fractions for Cabibbo-suppressed decays and at Belle
International audienceWe present measurements of the branching fractions for the singly Cabibbo-suppressed decays and , and the doubly Cabibbo-suppressed decay , based on 980 of data recorded by the Belle experiment at the KEKB collider. We measure these modes relative to the Cabibbo-favored modes and . Our results for the ratios of branching fractions are , , and , where the uncertainties are statistical and systematic, respectively. The second value corresponds to , where is the Cabibbo angle; this value is larger than other measured ratios of branching fractions for a doubly Cabibbo-suppressed charm decay to a Cabibbo-favored decay. Multiplying these results by world average values for and yields , , and , where the third uncertainty is due to the branching fraction of the normalization mode. The first two results are consistent with, but more precise than, the current world averages. The last result is the first measurement of this branching fraction