Endeavours leading to the study of glycerol oxidation result from the imperative necessity for wise utilization of surplus glycerine generated as by-product from biodiesel manufacture. The oxidation of glycerol is one of the most promising reactions as it leads to the generation of valuable glycerol derivatives that find broad application in pharmaceutical, polymer, and food industries. This review highlights the processing alternatives for glycerol by means of biocatalyst-mediated, heterogeneous, homogeneous, and electrochemical oxidation. The current state of the art is evaluated and recommendations for further research and future directions are included.

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In the present paper, a Visual Basic program was developed by describing the set of equations required to determine the value of seven different psychrometric properties (partial pressure of water vapor, absolute humidity, percentage humidity, relative humidity, dew point temperature, humid heat, humid volume or adiabatic saturation temperature) for mixtures of water vapor in air given the dry bulb temperature, the total atmospheric pressure and one additional parameter. Eight different cases are studied according to the corresponding input parameters. ß 2015 Wiley Periodicals, Inc. Comput Appl Eng Educ 24:39-43, 2016; View this article online at wileyonlinelibrary.com/journal/cae;

& An HPLC method for the separation of glycerol oxidation products, namely glyceraldehyde, dihydroxyacetone, mesoxalic, tartronic, and glycolic and glyceric acids on an ion-exchange 8% cross-linked calcium sulfonated divinylbenzene-styrene resin column was developed and validated. The conditions reported include temperature (70 C), flow rate (0.5 mL=min) and concentration of the mobile phase (3 mM H 2 SO 4 ) using isocratic elution with ultraviolet and refractometric detectors. The effect of the mobile phase flow rate and concentration as well as column temperature on the resolution of peaks is described. Excellent correlation coefficient in the calibration model was observed for all analytes over the concentration range of 0.5 to 10 mg=mL. The method was also validated in terms of intra-day precision, sensitivity, accuracy, and detection and quantification limits. The method conditions were applied to the identification of products derived from the chemical oxidation of glycerol.

In this research, rheological parameters of cement suspensions modified with different doses of two types of superplasticizers (SPs) were evaluated with an alternative method of centrifugation. It was determined that the critical normal and shear stresses (yield values), and the water/solid ratio alter with the additive dose, the additive type as well and the magnitude of centrifugal forces. The results obtained reveal that the method of centrifugation might serve for determination of dispersing effectiveness of SPs and rheological parameters of suspensions in general.

Review: 167 refs.

<span><p class="TTPAbstract"><span lang="EN-US">A three electrode system was used for the analysis of potentiodynamic polarization studies of glycerin in platinum electrodes. Particular attention was devoted to the estimation of diffusion coefficient of glycerin in platinum electrodes by the use of electrochemical techniques such as the sweep of the potential. Cyclic voltammograms were recorded at different sweep rates (0.01 and 0.07 V·s-1). Randles-Sevcik equation was taken into consideration and a linear relationship was found between </span><span lang="DE">the peak current and the square root of the voltage sweep rate from where the value of diffusion coefficient could be determined. The values of Tafel constants, useful in the understanding of electrochemical reaction kinetics are also reported in the present paper.</span><b><span lang="EN-US"><o:p></o:p></span></b></p>

Over the years, many of the most demanding industries have relied on fluid flow analysis and process design to ensure proper operation and to maximize profitability and operational safety. It is well known that many of the fluids used in industrial applications behave in turbulent regime. As a result, clear and proper understanding of parameters such as transitional flow, measurement of instantaneous velocity in a fluid stream, flow behavior at lower and higher velocities inside tubes or pipes and resistance of an object in a fluid environment is important. In the present paper we study the laminar boundary layer on a flat plate and also discuss the case of turbulent flow using integral momentum balance for the boundary layer to obtain a general momentum integral relation after using an empirical or assumed velocity distribution. Furthermore, we determine the boundary layer thickness and discuss two methods to estimate drag coefficient at different distances from the leading edge. Results from the current research can be applied by the industry to model complex parameter dependencies and to estimate and simulate the presence of drag on solids with particular geometrical properties of size and shape.