Grain Relativity Humidity Real-Time Prediction Based on Different Saturated Humidity Models in the Process of Storage
A mathematical model was selected and established based on the granary internal temperature and humidity real-time monitoring. In the experiment, the relative humidity of different water content corns were predicted by using different saturated vapor pressure formula and select the fittest model by comparing with the calculations and the test results. The humidity calculated by the saturated vapor pressure at formula 3 was closest to the actual measurement in them. Using the model it was possible to predict the evolution of grain relativity humility. During the experiment process, the calculation appeared the fluctuation because the internal humidity of grain was greatly influenced by the temperature and relativity humidity of the environment.
The selection of sorption isotherm equations for wheat based on the fitting of available data
Abstract Thirty-three sources of EMC/ERH data for wheat were identified, from which 1109 experimental points were extracted. Nineteen sources covered a range of temperatures. Five commonly cited EMC/ERH equations, Chen-Clayton, Modified-Chung-Pfost, Modified-Henderson, Modified-Oswin and Strohman-Yoerger, were compared for their ability to fit 29 sets of wheat data from these 19 sources. The Modified-Chung-Pfost and the Modified-Oswin equations gave the best fit for r.h. = f ( M , T ) and M = f (r.h., T ) respectively. Both equations were then used to fit sub-sets of the data comparing adsorption, desorption, low temperature, hard, soft and durum varieties with the overall fit to the data. The adsorption and desorption equations gave quite distinct curves. The low temperature fit did not differ greatly from the overall. Amongst the varieties, the hard wheat at low temperature showed the greatest difference from the overall fit. The larger data set than previously available and the equations fitted provide a sound basis for future work on the drying and storage of wheat.
Inhibition of Mild Steel Corrosion Using L-tryptophan and Synergistic Surfactant Additives
The corrosion inhibition characteristics of nitrogen containing amino acid L-tryptophan on mild steel in 0.1 M HCl solution, in the temperature range of 30-50 o C, was studied by weight loss and potentiodynamic polarization measurements. L-tryptophan significantly reduces the corrosion rates of mild steel; the maximum inhibition efficiency being 83% at 50 o C in presence of inhibitor concentration of 500 ppm. The effect of the addition of very small concentrations of anionic surfactant, sodium dodecyl sulfate (SDS), and of cationic surfactant, cetyl trimethyl ammonium bromide (CTAB), on the corrosion inhibition behavior of L-tryptophan was also studied. The inhibition efficiency (IE) of L-tryptophan significantly improved in presence of both surfactants. The effect of SDS and CTAB on the corrosion inhibition behavior of L-tryptophan appears to be synergistic in nature, the values of synergism parameter being greater than unity. The adsorption of inhibitors on mild steel surface obeyed Langmuir’s adsorption isotherm. The calculated thermodynamic parameters for adsorption reveal a strong interaction between the inhibitors and the mild steel surface. The results obtained by electrochemical studies are consistent with the results of the weight loss measurements. L-tryptophan acts more anodic than cathodic inhibitor.