Thermal degradation of cereal straws in air and nitrogen

Multigram quantities (2.5-10 g) of highly purified IgG were obtained within 4 h from serum by using Avid AL packed in a radial-flow column. Avid AL is an affinity gel containing a synthetic, low-mol-wt ligand capable of selectively binding IgG from serum of all animal species tested. By packing the gel in a radial-flow column up to 500 mL, a high flow rate of 50 mL/min can be achieved without adversely affecting the performance of the gel and the purity of the isolated antibody.     

Amelioration of methane yield in cheese whey fermentation by controlling the pH of the methanogenic stage

A two-stage, no-mix anaerobic digester of 145 L capacity was used to investigate the effect of controlling the pH of the methanogenic stage on the biogas production and the pollution potential reduction of acid cheese whey. The digester was operated at a 15-d hydraulic retention time, and a temperature of 35°C. Controlling the pH of the methanogenic stage increased the biogas production rate and methane yield by 77.77 and 289.00%, respectively. Reductions of up to 32.19, 44.44, and 35.86% in the COD, solids and nitrogen were achieved.     

Kinetics of batch production of single-cell protein from cheese whey

A kinetic model for single-cell protein batch fermentation was developed using the numerical simultaneous integration approach of the fourth-order Runge-Kutta method. The model takes into account the effect of substrate inhibtion, maintenance energy, and cell death on the cell growth and substrate utilization during the fermentation process. The theoretical results obtained from the model compared well with the experimental data. The model was used to study the effect of the initial substrate concentration on the lag period, fermentation time, specific growth rate, population size, and cell productivity of batch fermentation. Increasing the initial substrate concentration increased the lag period and fermentation time and decreased the specific growth rate and cell yield. The growth limiting substrate concentration was 2.9 g/L, whereas the growth inhibiting substrate concentration was 69.0 g/L. Increasing the initial substrate concentration above 150 g/L significantly decreased the yeast population size.     

Destabilizing effect of time-dependent oblique magnetic field on magnetic fluids streaming in porous media

The present work studies Kelvin-Helmholtz waves propagating between two magnetic fluids. The system is composed of two semi-infinite magnetic fluids streaming throughout porous media. The system is influenced by an oblique magnetic field. The solution of the linearized equations of motion under the boundary conditions leads to deriving the Mathieu equation governing the interfacial displacement and having complex coefficients. The stability criteria are discussed theoretically and numerically, from which stability diagrams are obtained. Regions of stability and instability are identified for the magnetic fields versus the wavenumber. It is found that the increase of the fluid density ratio, the fluid velocity ratio, the upper viscosity, and the lower porous permeability play a stabilizing role in the stability behavior in the presence of an oscillating vertical magnetic field or in the presence of an oscillating tangential magnetic field. The increase of the fluid viscosity plays a stabilizing role and can be used to retard the destabilizing influence for the vertical magnetic field. Dual roles are observed for the fluid velocity in the stability criteria. It is found that the field frequency plays against the constant part for the magnetic field.     

Growth rate determination of heterogeneous microbial population in swine manure

The effect of manure concentration on the growth of the heterogeneous microbial population under batch condition was studied. Four manure concentrations were used in the study. The dehydrogenase activity was used as a measure of the active biomass in the manure. The chemical oxygen demand test was used to measure the change in organic material caused by biological activities. The growth curve of the heterogeneous microbial population in swine manure was essentially similar to that of a pure culture grown batchwise in that it had the four principle phases: lag, exponential growth, stationary, and death. The exponential growth phase followed a diauxic growth pattern. High concentration of manure had an inhibitory effect on the microbial growth. Manure diluted less than 1:3 (manure:water) depressed the specific growth rate of the microbial population.     

Continuous production of biogas from dairy manure using an innovative no-mix reactor

Applied Biochemistry and Biotechnology - A 25 L no-mix anaerobic digester was designed and fabricated. The digester was designed to act as liquid-solid separator. The sludges obtained from the...     

Gamma-radiation combined with tricycloazole to protect tempera paintings in ancient Egyptian tombs (Nile Delta,Lower Egypt)

In order to comprehensively understanding the metabolism process of fluvastatin, the stable isotope-labeled (3R, 5S)-fluvastatin and (3S, 5R)-fluvastatin were required. Both of (3R, 5S)-fluvastatin and (3S, 5R)-fluvastatin were synthesized via a seven steps procedure starting from aniline and [²H₆] 2-bromopropane. Two versions of deuterium labeled compound revealed over 98% deuterium enrichment, using as an internal standard.

     

Determination of reaction kinetics of wheat straw using thermogravimetric analysis

A simple rapid method of enzyme labeled anti-isotype assay (ELIA) for detection of monoclonal isotype on hybridoma cells is proposed. This alternative method was first carried out on hybridoma cell lines 147C11 and 257C11 produced against Trypanosoma cruzi and male accessory secretion of Panstrongylus megistus, respectively. The monoclonal antibodies produced by these hybridoma were characterized by this method as IgM (147C11) and IgG1 (257C23) isotypes, allowing evaluation of isotype without having to wait until the concentration of antibody present in the supernatant itself rises. Results were confirmed by Ouchterlony immunodiffusion. The proposed method offers the advantages of a permanent rapid procedure for light microscopy.     

Modeling batch production of single cell protein from cheese whey

A mathematical model was developed to describe the growth and death of the yeastKluyveromyces fragilis in cheese whey under aerobic batch fermentation. The model is capable of determining the lengths of the lag, exponential, stationary, and death phases as well as the number of yeast cells during these phases. It predicted the experimental results withR ² value of 0.99. The total number of yeast cells synthesized in the fermenter was reduced to 55% after 52 h (46 h from the beginning of the death phase). The high percentage of curvival was attributed to the fact that the yeastK. fragilis reproduced by sporulation (each ascus had 8–10 spores) during the death phase owing to the lack of nutrient. The spores protected the yeast from dying. The maximum specific growth rate (during exponential phase) was 0.23 h^?1, whereas the maximum specific death rate (during the death phase) was ?0.32 h^?1.