Kinetics of ethanol fermentation with high biomass concentration considering the effect of temperature

A model of ethanol fermentation considering the effect of temperature was developed and validated. Experiments were performed in a temperature range from 28 to 40°C in continuous mode with total cell recycling using a tangential microfiltration system. The developed model considered substrate, product and biomass inhibition, as well as an active cell phase (viable) and an inactive (dead) phase. The kinetic parameters were described as functions of temperature.     

Measurement of radon concentrations and their annual effective doses in soils and rocks of Jaintiapur and its adjacent areas,Sylhet, North-east Bangladesh

Journal of Radioanalytical and Nuclear Chemistry - The study investigates the measurement of radon concentration in soils and rocks as a natural tracer for exploring uranium mineralization, first...     

Regular groups on generalized quadrangles and nonabelian difference sets with multiplier -1

This is a first approach to the study of regular generalized quadrangles (i.e. generalized quadrangles with an automorphism group sharply 1-transitive on points). In this paper we point out how the problem is connected to the theory of difference sets with multiplier-1. First, some of the results in [3] on difference sets with multiplier-1 are extended to the nonabelian case; then, these new results on difference sets are used to prove nonexistence theorems for regular GQs of even order s=t.Dedicated to Otto Wagner on the occasion of his 60th birthday     

Extended partial geometries with minimal μ

Recently Fisher and Hobart extended the original work of Buekenhout and Hubaut on extended generalized quadrangles with a certain minimal value (minimal ) for the nonempty residue intersections. We show that there is another minimal which is sometimes better than the earlier one, and we extend all this to the case of extended partial geometries. We examine especially the triangular case, and find only a few new possibilities, which we are unable to settle, although some of these look extremely interesting.     

Hydration of Portland cement with red mud as mineral addition

Journal of Thermal Analysis and Calorimetry - The use of red mud from Bayer process in association with Portland cement has been shown to be promising because of its good performance on the...     

Electronic energy transfer in benzophenone adlayer

The extent to which energy transfer occurs in electronically excited organic adlayer films on dielectric surfaces is investigated. Migration and subsequent trapping of the energy in the film are observed by pumping the singlet state of an organic adlayer of benzophenone and by monitoring the phosphorescence and fluorescence lifetimes. To observe the effects of adsorption, benzophenone was chosen as the adlayer because the energies of its well characterizedn, carbonyl states are remarkably sensitive to solvent interactions. Upon excitation with a nitrogen laser, the perturbation on the electronic states of benzophenone by the substrate caused the emergence of the normally absent fluorescence from the adlayer traps at the interface between the surface of the dielectric substrate and the adlayer. Energy transfer to this interface was observed as a function of film thickness. On the surface of a single crystal of an organic crystal, naphthalene, energy transfer from the adlayer to the substrate was observed, whereas such transfer was not energetically possible with the other dielectric surfaces.     

Synthesis and characterization of Al2O3/Cr2O3-based ceramic pigments

The synthesis and the characterization of Al₂O₃-based nanocrystalline inorganic pigments are reported. The pigments were synthesized by the polymeric precursor (Pechini method) using Cr₂O₃ as chromophore. XRD results only evidenced the corundum phase. The average particle size was about 34 nm. The samples were also characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG), and CIE-L*a*b* calorimetry. The pigments obtained in this work presented different colors, ranging from green to rose. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis,catalytic properties and biological activity of new water soluble ruthenium cyclopentadienyl PTA complexes [(C5R5)RuCl(PTA)2] (R = H,Me; PTA = 1,3,5-triaza-7-phosphaadamantane)

The new water soluble ruthenium complexes [(C5R5)RuCl(PTA)2] (R = H, Me; PTA = 1,3,5-triaza-7-phosphaadamantane) were synthesised and characterised. Their evaluation as regioselective catalysts for hydrogenation of unsaturated ketones in aqueous biphasic conditions and as cytotoxic agents towards the TS/A adenocarcinoma cell line is briefly presented.