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Okra, of high nutritional potential, is one of the underutilized indigenous vegetables in Ethiopia. A food based-intervention specifically dietary diversification is an affordable and sustainable strategy to meet the demand of adequate food supply and population growth. One way of ensuring dietary diversity is to search and promote underutilized indigenous plant species such as okra. Therefore, the objective of this study was to determine nutritional and anti-nutritional factors content of the seeds of eight okra accessions (OPA#1, OPA#2, OPA#3, OPA#4, OPA#5, OPA#6, OPA#7 and OPA#8) grown at Assosa Agricultural Research Center in Benishangul Gumuz region, Ethiopia. Molar ratios of the seeds were also calculated and compared to the critical values to predict the mineral bioavailability. All the analyses were conducted using official standard procedures and grade standard reagents. The results of this study revealed that the proximate composition (g/100 g) of the seed accessions varied significantly (P Key words: Okra, Seed, Accession, Proximate composition, Minerals, Anti-nutritional factors, INTRODUCTION Okra (Abelmoschus esculentus) is a vegetable crop that belongs to the Malvaceae family and which originated in Ethiopia [1]. Okra is now widely spread and grown in tropical, sub-tropical [...]

Thermodynamic studies on CaLaFe11O19(s) were carried out using Knudsen effusion mass spectrometry and calorimetry, viz. differential scanning calorimetry and high temperature oxide melt solution calorimetry. Standard molar Gibbs free energy of formation (Δ f G 0 m ), enthalpy of formation and heat capacity (C 0 p, m ) of the compound were calculated as a function of temperature for the first time. C 0 p, m (CaLaFe11O19) was determined and used for second law analysis, from which enthalpy and entropy of formation of the compound were calculated and the respective values are: Δ f H 0 m (298.15K)/kJmol−1=−6057(±8) and S 0 m (298.15K)/JK−1 mol−1=427(±5). Δ f H 0 m (298.15K)/kJmol−1: −6055(±6) was also calculated using oxide melt solution calorimetry, which is in close agreement with the second law value. A heat capacity anomaly was also observed at T=684K. A table of thermodynamic data from 298.15K to 1000K for CaLaFe11O19(s) was also constructed to represent an optimized set of data. [ABSTRACT FROM AUTHOR]

Abstract: Three ternary oxides LiAl5O8(s), LiAlO2(s) and Li5AlO4(s) in the system Li–Al–O were prepared by solid-state reaction route and characterized by X-ray powder diffraction method. Equilibrium partial pressure of CO2(g) over the three-phase mixtures {LiAl5O8(s)+Li2CO3(s)+5Al2O3(s)}, {LiAl5O8(s)+5LiAlO2(s)+2Li2CO3(s)} and {LiAlO2(s)+Li5AlO4(s)+2Li2CO3(s)} were measured using Knudsen effusion quadrupole mass spectrometry (KEQMS). Solid-state galvanic cell technique based on calcium fluoride electrolyte was used to determine the standard molar Gibbs energies of formations of these aluminates. The standard molar Gibbs energies of formation of these three aluminates calculated from KEQMS and galvanic cell measurements were in good agreement. Heat capacities of individual ternary oxides were measured from 127 to 868K using differential scanning calorimetry. Thermodynamic tables representing the values of Δf H 0(298.15K), S 0(298.15K) S 0(T), C p 0(T), H 0(T), {H 0(T)–H 0(298.15K)}, G 0(T), Δf H 0(T), ΔfG0(T) and free energy function (fef) were constructed using second law analysis and FACTSAGE thermo-chemical database software. [Copyright &y& Elsevier]

Abstract: Rare-earth orthoferrites, RFeO3, and rare-earth iron garnets (RIGs) R 3Fe5O12 (R=rare-earth elements) were prepared by citrate–nitrate gel combustion method and characterized by X-ray diffraction method. Isobaric molar heat capacities of these oxides were determined by using differential scanning calorimetry from 130 to 860K. Order–disorder transition temperatures were determined from the heat capacity measurements. The Néel temperatures (T N) due to antiferromagentic to paramagnetic transitions in orthoferrites and the Curie temperatures (T C) due to ferrimagnetic to paramagnetic transitions in garnets were determined from the heat capacity data. Both T N and T C systematically decrease with increasing atomic number of R across the series. Lattice, electronic and magnetic contributions to the total heat capacity were calculated. Debye temperatures as a function of absolute temperature were calculated for these compounds. Thermodynamic functions like , , H o, G o, , , , , and have been generated for the compounds RFeO3(s) and R 3Fe5O12(s) based on the experimental data obtained in this study and the available data in the literature. [Copyright &y& Elsevier]

Abstract: Ternary oxides such as BaFe12O19(s), BaFe2O4(s), Ba2Fe2O5(s), Ba3Fe2O6(s) and Ba5Fe2O8(s) of Ba–Fe–O system were synthesized by solid-state reaction route taking stoichiometric proportions of preheated BaCO3(s) and Fe2O3(s) powders of high purities. The standard molar heat capacities of these ternary oxides were determined using differential scanning calorimetry from 310 to 850K. A heat capacity anomaly was observed for BaFe12O19(s), a member of magnetoplumbite group and largely used as hard ceramic magnet exhibited a heat capacity anomaly at 725K in differential scanning calorimetric result. This anomaly is due to the magnetic order–disorder transition from ferrimagnetic state to paramagnetic state of the compound and the transition temperature has been termed as Curie temperature (T C). Thermodynamic functions such as , , , , , , , fef (free energy function), and for these ternary oxides were also calculated from 298 to 1000K using the second law analysis. [Copyright &y& Elsevier]

Abstract: The citrate–nitrate gel combustion route was used to prepare SrFe2O4(s), Sr2Fe2O5(s) and Sr3Fe2O6(s) powders and the compounds were characterized by X-ray diffraction analysis. Different solid-state electrochemical cells were used for the measurement of emf as a function of temperature from 970 to 1151K. The standard molar Gibbs energies of formation of these ternary oxides were calculated as a function of temperature from the emf data and are represented as (SrFe2O4, s, T)/kJmol−1 (±1.7)=−1494.8+0.3754(T/K) (970⩽T/K⩽1151). (Sr2Fe2O5, s, T)/kJmol−1 (±3.0)=−2119.3+0.4461(T/K) (970⩽T/K⩽1149). (Sr3Fe2O6, s, T)/kJmol−1 (±7.3)=−2719.8+0.4974(T/K) (969⩽T/K⩽1150). Standard molar heat capacities of these ternary oxides were determined from 310 to 820K using a heat flux type differential scanning calorimeter (DSC). Based on second law analysis and using the thermodynamic database FactSage software, thermodynamic functions such as Δf H°(298.15K), S°(298.15K) S°(T), Cp °(T), H°(T), {H°(T)–H°(298.15K)}, G°(T), free energy function (fef), Δf H°(T) and Δf G°(T) for these ternary oxides were also calculated from 298 to 1000K. [Copyright &y& Elsevier]

Abstract: The thermodynamic properties of three different types of ternary oxides RFeO3(s), R 3Fe5O12(s) and RFe2O4(s) (where R=Ho and Er) have been determined by calorimetric and solid-state galvanic cell methods. Heat capacities of RFeO3(s) and R 3Fe5O12(s) have been determined by differential scanning calorimetry from 130 to 860K. Heat capacity measurements from 130 to 860K revealed λ-type anomalies for RFeO3(s) and R 3Fe5O12(s) compounds which are assigned due to magnetic order–disorder transitions. The oxygen chemical potentials corresponding to the three-phase equilibria involving these ternary oxides have been determined by using solid-state electrochemical cells. The standard molar Gibbs energies of formation of RFeO3(s), R 3Fe5O12(s) and RFe2O4(s) have been computed from the oxygen potential data. Based on the thermodynamic information, oxygen potential diagrams have been computed for the systems R–Fe–O (R=Ho and Er) at two different temperatures: and 1450K. Thermodynamic functions like , , H o, G o, , , , , and have been generated for the compounds RFeO3(s) and R 3Fe5O12(s) based on the experimental data obtained in this study and the available data in the literature. [Copyright &y& Elsevier]

Abstract: Two compounds, BaNd2Fe2O7(s) and BaNdFeO4(s) in the quaternary system Baph name="sbnd" />Feepared by citrate–nitrate gel combustion route and characterized by X-ray diffraction analysis. Heat capacities of these two oxides were measured in two different temperature ranges: (i) 130–325K and (ii) 310–845K, using a heat flux type differential scanning calorimeter. Two different types of solid-state electrochemical cells with CaF2(s) as the solid electrolyte were employed to measure the e.m.f. as a function of temperature. The standard molar Gibbs energies of formation of these quaternary oxides were calculated as a function of temperature from the e.m.f. data. The standard molar enthalpies of formation from elements at 298.15K, (298.15K) and the standard entropies, (298.15K) of these oxides were calculated by the second law method. The values of (298.15K) and (298.15K) obtained for BaNd2Fe2O7(s) are: −2756.9kJmol−1 and 234.0JK−1 mol−1 whereas those for BaNdFeO4(s) are: −2061.5kJmol−1 and 91.6JK−1 mol−1, respectively. [Copyright &y& Elsevier]

Abstract: Antimicrobial effect of chitosan edible film incorporating garlic oil (GO) was compared with conventional food preservative potassium sorbate (PS) and bacteriocin nisin (N) at various concentrations. This activity was tested against food pathogenic bacteria namely Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Listeria monocytogenes and Bacillus cereus. Mechanical and physical properties were characterized and Fourier Transform Infrared (FTIR) was also performed to determine functional groups interactions between the matrix and added agent. Incorporation of GO up to levels at least 100μl/g, PS at 100mg/g or N at 51,000IU/g of chitosan were found to have antimicrobial activity against S. aureus, L. monocytogenes, and B. cereus. At these levels, the films were physically acceptable in term of appearance, mechanical and physical properties. GO components did not affect the physical and mechanical properties of chitosan films as it did not have any interaction with the functional groups of chitosan as measured by FTIR. [Copyright &y& Elsevier]

Abstract: The citrate–nitrate gel combustion route was used to prepare SrFe12O19(s) powder sample and the compound was characterized by X-ray diffraction analysis. A solid-state electrochemical cell of the type: (−)Pt, O2(g)/{CaO(s)+CaF2(s)}//CaF2(s)//{SrFe12O19(s)+SrF2(s)+Fe2O3(s)}/O2(g), Pt(+) was used for the measurement of emf as a function of temperature from 984 to 1151K. The standard molar Gibbs energy of formation of SrFe12O19(s) was calculated as a function of temperature from the emf data and is given by: (SrFe12O19, s, T)/kJmol−1 (±1.3)=−5453.5+1.5267×(T/K). Standard molar heat capacity of SrFe12O19(s) was determined in two different temperature ranges 130–325K and 310–820K using a heat flux type differential scanning calorimeter (DSC). A heat capacity anomaly was observed at 732K, which has been attributed to the magnetic order–disorder transition from ferrimagnetic state to paramagnetic state. The standard molar enthalpy of formation, (298.15K) and the standard molar entropy, (298.15K) of SrFe12O19(s) were calculated by second law method and the values are −5545.2kJmol−1 and 633.1JK−1 mol−1, respectively. [Copyright &y& Elsevier]

Cellular components of thermophilic organisms (enzymes, proteins and nucleic acids) are also thermostable. Apart from high temperature they are also known to withstand denaturants of extremly acidic and alkaline conditions. Thermostable enzymes are highly specific and thus have considerable potential for many industrial applications. The use of such enzymes in maximising reactions accomplished in the food and paper industry, detergents, drugs, toxic wastes removal and drilling for oil is being studied extensively. The enzymes can be produced from the thermophiles through either optimised fermentation of the microorganisms or cloning of fast-growing mesophiles by recombinant DNA technology. In this review, the source microorganisms and properties of thermostable starch hydrolysing amylases, xylanases, cellulases, chitinases, proteases, lipases and DNA polymerases are discussed. The industrial needs for such specific thermostable enzyme and improvements required to maximize their application in the future are also suggested. [Copyright &y& Elsevier]

Highly oxidizing nature of electronically excited uranyl ion has been utilized to degrade thionine dye with the aim of developing a new methodology for degradation of organic pollutants/waste. In this connection, photo-degradation of thionine has been studied under different conditions. It was found that in HClO4 medium photo-degradation is faster than in H2SO4 medium on photolysis with 254 nm light. Experiments with visible light irradiation of the same system were studied in the presence of H2O2. In the presence of H2O2, hydroxyl radicals formed during oxidation of U(IV)/U(V) were found to enhance the rate of photo-degradation. [Copyright &y& Elsevier]

Abstract: Solid state reactions of UO2 and ZrO2 in mild oxidizing condition followed by reduction at 1673K showed enhanced solubility up to 35mol% of zirconium in UO2 forming cubic fluorite type Zr y U1− y O2 solid solution. The lattice parameters and O/M (M=U+Zr) ratios of the solid solutions, Zr y U1− y O2+ x , prepared in different gas streams were investigated. The lattice parameters of these solid solutions were expressed as a linear equation of x and y: a 0 (nm)=0.54704−0.021x –0.030y. The oxidation of these solid solutions for 0.1⩽ y ⩽0.2 resulted in cubic phase MO2+ x up to700K and single orthorhombic zirconium substituted α-U3O8 phase at 1000K. The kinetics of oxidation of Zr y U1− y O2 in air for y =0–0.35 were also studied using thermogravimetry. The specific heat capacities of Zr y U1− y O2 (y =0–0.35) were measured using heat flux differential scanning calorimetry in the temperature range of 334–860K. [Copyright &y& Elsevier]