Moisture influence on fungal growth in black pepper

The moisture content at which fungal growth proliferated on black pepper was determined at different relative humidities. At 18% moisture content, fungal growth occurred but this was not recorded at the next lower moisture content of 13.9%. Microscopic examination of infected fresh green pepper showed the presence of species of Trichothecium, Colletotrichum and Fusarium. In black pepper, species of Aspergilli and Penicillium were observed.     

Thermodynamic stability of Sb2O4 by a solid oxide electrolyte e.m.f. method

The standard Gibbs energy change for the reaction Sb₂O₃ (orthorhombic) (orthorhombic) was measured using the following galvanic cell: Pt, Sb₂O₃(ortho), Sb₂O₄ (ortho), platinum black |15 Wt % Y₂O₃-stabilized ZrO₂|O₂(air,P _{o 2} = 0.21 atm), Pt over the range 585 to 828K. Reproducible e.m.f. values were obtained only when the otherwise poorly electronic conducting oxide mixture was blended with platinum black. The standard Gibbs energy change forthis reaction was found to be (G_R ^o ± 0.81) (kJ) = –16833 + 0.0S019T/K. This yielded thestandard Gibbsenergy offormation G_R ^o of Sb₂O₄ (ortho) to be as follows: [\gDG₁ ^o(Sb₂O₄, ortho) \+- 1.61] (kJ) \s= \t-854.89 \s+ 0.33614T/K. A third-law treatment yielded a value of \t-880.55 (\+-1.21) kJmol^\t-1 for \gDH _1,298 ^o of Sb₂O₄ (ortho).     

Estimation of Periodically Changing Failure Rate

This paper considers two life testing procedures (progressively censored samples and Bartholomew's experiment) under the assumption that the life of an item follows the exponential distribution. The failure rates are different under n different conditions of usage of the item at regular intervals of time. The maximum likelihood estimates of the n failure rates have been derived along with their asymptotic variances for both types of data (when failure times are recorded and when only the number of items failing in each interval are recorded). A numerical example illustrates the type of data and relevant calculations for the experiment involving progressively censored samples.     

Factors affecting the functioning of solid state fluoride galvanic cells

Fluoride galvanic cells employing CaF₂ as electrolyte have not been as extensively employed for thermodynamic characterization of alloys and compounds as the oxide electrolyte cells based on stabilized zirconia. However, CaF₂ galvanic cells have many advantages over oxide electrolyte cells. These advantages, as well as the factors affecting the proper functioning of the CaF₂ cells, are discussed, highlighting the experimental aspects, such as the interfence by the gas phase, choice of the reference electrode, and the volatility and compatibility of the materials.     

Thermal behaviour of strontium tartrate single crystals grown in gel

Thermal behaviour of strontium tartrate crystals grown with the aid of sodium metasilicate gel is investigated using thermogravimetry (TG) and differential thermal analysis (DTA). Effect of magnetic field and dopant (Pb)²⁺ on the crystal stability is also studied using thermal analysis. This study reveals that water molecules are locked up in the lattice with different strengths in the grown crystals.     

Oxygen Potential in the System UMoO6/UMoO5 by the Solid Oxide Electrolyte Emf Method

The emf of the galvanic cell Pt|UMoO₆UMoO₅|ZrO₂-Y₂O₃|O₂(air, Po₂=0.21 atm)|Pt, measured from 776 to 1127 K, was determined to be E = 751.7−0.4909 ±4.3 mV. Using the standard Gibbs energy of formation, ^fΔG°, for UMoO₆ reported in the literature from transpiration studies, the ^fΔG° for UMoO₅ is calculated to be ^fΔG°〈UMoO₅〉=−1816.9+0.3748T±6.0 U-mol⁻¹ The magnitudes of the standard entropies of formation, ^fΔS°, for UMoO₆ and UMoO₅ were evaluated from those values reported for the binary oxides which constitute the ternary compounds.