Cationization of cotton using cattle hoof and horn for salt-free reactive dyeing

Cattle hoof and horn keratin hydrolysate from cattle hoofs and horns were successfully extracted and used to cationize cotton fabric. The effect of cationization was tested by dyeing the cationized cotton fabric using reactive dyes (cationized sample). The results were compared to conventionally dyed cotton fabric sample without cationization. The UV/VIS absorption result showed 6% improvement in exhaustion; the Color Eye K/S result gave 4.5% improvement in fixation and 6.8% in dye utilization for reactive dye (H-Reactive Red). Acceptable color fastness to washing (4/5) and light fastness (7) were achieved on cationized sample.     

Steady state inferential modeling of temperature and pressure in an air-swept coal pulverizing ball mill

Mill discharge temperature and differential pressure have a strong effect on efficiency and safety of a coal fired power plant. Therefore, it is imperative that they are closely monitored and controlled during mill operation to keep their levels within a predetermined safe and efficient operating range regardless of the rate at which the raw coal is fed to the mill. One way to achieve this is through a control schedule that compares the value obtained from the process to the stored set-point value to determine if there is any deviation that requires correction. This paper describes a steady state model that could be used alongside conventional controllers as an on-line shadow that provides inferential estimates of desired temperatures and pressure drops in the mill circuit which can be continuously compared with the actual values for adjustment. This would not only help to avoid the difficulties associated with direct measurement but also provide a means for early detection of drifts and failing sensors and serve as a temporal back-up for the out-of-order sensors. The model was tested using industrial data collected from four ball mills at a coal fired power plant in South Africa and the results show a reasonable agreement between the measured data and model predictions both qualitatively and quantitatively within a 5% error margin. The model outputs were found to be highly sensitive to the variation in mill loading, the primary air (PA) flow and the mill channel dimensions. Therefore, for validity of this model, accurate determination of all significant parameters is essential. For now, the model is only valid for the ball mills involved in the current study, but with availability of data it can be reproduced elsewhere.     

Modeling the RTD of an industrial overflow ball mill as a function of load volume and slurry concentration

The role of residence time distribution (RTD) in the accuracy of milling simulation is well appreciated in literature. Accordingly, the development of models that can accurately predict the RTD at various mill operating conditions would be of considerable benefit to the milling industry. In this paper, a 3-parameter RTD model has been derived using the concept of serial stirred mixers with a dead zone. The model parameters were optimized by minimizing the error between experimental tracer response data and model predictions using a MATLAB algorithm. Based on the optimum values of the model parameters, the mean residence time of slurry was evaluated and the effects of ball load volume and slurry concentration examined. The results revealed that the mean residence time of slurry inside the mill is affected to a larger extent by slurry concentration than the ball load volume. An empirical correlation was developed to predict the mean residence time as a function of slurry concentration, ball load volume and slurry feed rate. Over the range of conditions investigated, the mean residence time was observed to vary linearly with slurry concentration and ball load volume but inversely with feed flow rate. Lastly, a test case of the simulated mill product size distribution using the predicted RTD is presented displaying a close match with experimental data.     

Dyeing of male silk fibers with reactive dyes

A study of the dyeing behavior of male silk fibers (obtained from silk cocoons spun by male worms) was undertaken. Normal silk (composed of filaments made by male and female worms) was also dyed for comparison purposes. Physical and chemical characteristics of silk which may affect dyeing behavior were also investigated using scanning electron microscope (SEM) and Fourier transform infrared (FT‐IR) spectroscopy. From the results obtained in this research work, it can be concluded that male silk fibers tend to be finer than the normal silk fibers. The male silk fibers’ dye uptake was tested and found to be lower than that of normal silk. Adjustment of exhaustion salt and dyeing temperature to higher levels had significant improvement on dye uptake and K/S value for male silk.     

So-called "white bile" (clinico-experimental study)]

Based on clinical (37 cases of "white bile") and experimental (20 experiments) findings obtained by the authors, the characteristic of the so-called "white bile", observed in mechanic jaundice of various etiology, is given. It is pointed out that "white-bile" is the secretion of bile ducts and gallbladder mucous membrane--a colorless liquid, this secretion is permanently excreted and is a constant ingradient of colored bile while obturation of bile outflow ducts contributed only to its accumulation and detection.     

Removal of Pb(II) from aqueous media using adsorption onto polyaniline coated sisal fibers

Lead is one of the toxic metals that cause detrimental health disorders. Polyaniline (PAni) coated sisal fibers were prepared via in situ polymerization and used to remove Pb(II) from wastewater. PAni/SF was investigated on batch experiment to remove Pb(II) from wastewater as a function of contact time, pH, particle size, adsorbent, and adsorbate dose. Studies on kinetics revealed adsorption of Pb(II) obeyed pseudo second order. Adsorption equilibrium was suitably fitted in Langmuir isotherm with linear coefficient 0.99. Finally, PAni/SF composites show appreciable removal efficiency with a maximum adsorption capacity of 6.53 mg/g, consistent with adsorption capacity obtained from pseudo second order. J. VINYL ADDIT. TECHNOL., 25:189–197, 2019. © 2018 Society of Plastics Engineers