Description and applications of a 3D mathematical model for horizontal anode baking furnaces

In aluminum industry, carbon anodes are consumed continuously during alumina reduction in the electrolysis cells. Anodes are made of calcined coke, butt, and recycled anode particles and pitch as the binder. Green anodes are baked in large furnaces where they attain specific properties in terms of density, mechanical strength, and electrical conductivity. Baking is an important and costly step in carbon anode production. The proper operation of the furnace provides the required anode quality. Mathematical modeling allows the prediction of the heating profile of anodes during baking. Taking into account all the relevant phenomena, a 3D transient mathematical model was developed to simulate the different stages of the baking process in the furnace. The predictions give a detailed view of the furnace operation and performance. In this article, the 3D model is described, and the results on the impact of various parameters on furnace behavior are presented

Polysulfates block SARS‐CoV‐2 uptake through electrostatic interactions

Here we report that negatively charged polysulfates can bind to the spike protein of SARS-CoV-2 via electrostatic interactions. Using a plaque reduction assay, we compare inhibition of SARS-CoV-2 by heparin, pentosan sulfate, linear polyglycerol sulfate (LPGS) and hyperbranched polyglycerol sulfate (HPGS). Highly sulfated LPGS is the optimal inhibitor, with a half-maximal inhibitory concentration (IC50) of 67 μg/mL (approx. 1.6 μM). This synthetic polysulfates exhibit more than 60-fold higher virus inhibitory activity than heparin (IC50: 4084 μg/mL), along with much lower anticoagulant activity. Furthermore, in molecular dynamics simulations, we verified that LPGS can bind stronger to the spike protein than heparin, and that LPGS can interact even more with the spike protein of the new N501Y and E484K variants. Our study demonstrates that the entry of SARS-CoV-2 into host cells can be blocked via electrostatic interaction, therefore LPGS can serve as a blueprint for the design of novel viral inhibitors of SARS-CoV-2

A dynamic process model for predicting the performance of horizontal anode baking furnaces

Anode manufacturing is an important step during the production of primary aluminum, and baking is the costliest stage of the anode manufacturing process. The industrial challenge resides in obtaining a good anode quality while keeping the energy consumption, environmental emissions, and cost to minimum. A dynamic process model has been developed for horizontal anode baking furnaces. It covers all important phenomena such as fuel combustion, generation and combustion of volatiles (tar, methane, and hydrogen), air infiltration, and heat losses to the atmosphere and the foundation. The model was built using two coupled sub-models of the flue and the pit and was validated using the plant data. It simulates the dynamic behavior of the furnace and gives a prediction of its operation and performance. In this article, the modelling approach will be described, and the results of a number of case studies will be presented

Dendrimers as anti-inflammatory agents

Dendrimers constitute an intriguing class of macromolecules which find applications in a variety of areas including biology. These hyperbranched macromolecules with tailored backbone and surface groups have been extensively investigated as nanocarriers for gene and drug delivery, by molecular encapsulation or covalent conjugation. Dendrimers have provided an excellent platform to develop multivalent and multifunctional nanoconjugates incorporating a variety of functional groups including drugs which are known to be anti-inflammatory agents. Recently, dendrimers have been shown to possess anti-inflammatory properties themselves. This unexpected and intriguing discovery has provided an additional impetus in designing novel active pharmaceutical agents. In this review, we highlight some of the recent developments in the field of dendrimers as nanoscale anti-inflammatory agents

Computer simulation of an aluminum casting furnace

A dynamic model has been built to simulate the heat transfer in an aluminum casting furnace. Each furnace component (roof, floor, metal, gas) is treated as 1-D heat conduction medium except the gas which is treated as a single control volume. The model accounts for heat transfer by radiation, convection and conduction. The melting, known as Stefan problem, is solved by the enthalpy method. For purpose of validation, a complete batch on a 72-ton melter-holder is simulated. Satisfactory predictions are obtained for temperatures, heat fluxes as well as furnace efficiency