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  • Guldborg Armstrong posted an update 3 months, 2 weeks ago

    The development of sustainable and innovative products through solving the constantly raising demands of end users is one of the significant parts of research and development. Herein, the development of a green composite is reported with the reinforcement of naturally originated flax and artificial glass woven fabrics through incorporating with the methylene diphenyl diisocyanate (MDI) resin. The glass fabrics were treated with silane and flax fabrics by using NaOH before the composite production to increase the affinity of fibers toward the resin. Composite panels were developed with four different ratios of glass and flax woven fabric reinforcement (100/0, 83.33/16.67, 50/50, and 0/100) to investigate their performance with the MDI resin. The composites were characterized by tensile and flexural analysis to investigate the mechanical performances. The thermogravimetric characteristics of the composites were examined for checking the thermal stability of the produced composites. The surface morphology was investigated for observing the surfaces of the composites before and after applying tensile loads. Scanning electron microscopy (SEM) deployed EDX linear scanning was used for ensuring about the signals of different chemical constituents into the matrix. Fourier transform infrared spectroscopy (FTIR) was conducted for finding out the fingerprint of the chemical elements of the produced composites. Besides, the water absorption and moisture content tests were also conducted to examine the moisture absorption by the pure glass, flax, and hybrid composites. Tween 80 solubility dmso Further, statistical analysis of variances was performed to test the significance of the differences in the mechanical properties of the individual types of the composites developed. For investigating the relationship between the proportion of woven glass fabric in the reinforcement and the mechanical properties, regression analysis was used. The ANOVA test was also examined for checking the significance of the mechanical properties of the composites.Colombia is experiencing significant growth in its agricultural areas, its diverse production chains make the country an excellent candidate in the development of biorefineries, and as a result, there is an increasing need to take full advantage of biomass and obtain high value-added by-products from waste. In this sense, biorefineries are presented as a great alternative for the use of biomass; however, the methodologies of biorefinery synthesis lack a parameter that limits the growth of production lines under incremental exergetic and economic returns. This research develops a biorefinery synthesis methodology using an African palm biorefinery as a case study; a novel approach is developed to facilitate a stop criterion for biorefinery expansion through a combined consideration of economic incremental returns (IROI) and exegetical returns of investment (ExROI), avoiding unnecessary plant expansions or new processes that are not profitable or adequate in terms of useful energy. The development of this methodnew alternative for decision-making in regard to plant design, plant expansion projects, and implementation of subprocesses.G9a protein methyltransferase is a potential epigenetic drug target in different cancers and other disease conditions overexpressing the enzyme. G9a is responsible for the H3K9 dimethylation mark, which epigenetically regulates gene expression. Arg8 and Lys9 of the H3 substrate peptide are the two crucial residues for substrate-specific recognition and methylation. Several substrate competitive inhibitors are reported for the potent inhibition of G9a by incorporating lysine mimic groups in the inhibitor design. In this study, we explored the concept of arginine mimic strategy. The hydrophobic segment of the reported inhibitors BIX-01294 and UNC0638 was replaced by a guanidine moiety (side-chain moiety of arginine). The newly substituted guanidine moieties of the inhibitors were positioned similar to the Arg8 of the substrate peptide in molecular docking. Additionally, improved reactivity of the guanidine-substituted inhibitors was observed in density functional theory studies. Molecular dynamics, molecular mechanics Poisson-Boltzmann surface area binding free energy, linear interaction energy, and potential mean force calculated from steered molecular dynamics simulations of the newly designed analogues show enhanced conformational stability and improved H-bond potential and binding affinity toward the target G9a. Moreover, the presence of both lysine and arginine mimics together shows a drastic increase in the binding affinity of the inhibitor towards G9a. Hence, we propose incorporating a guanidine group to imitate the substrate arginine’s side chain in the inhibitor design to improve the potency of G9a inhibitors.A novel series of copper-activatable drugs intended for use against methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) were synthesized, characterized, and tested against the MSSA strain Newman and the MRSA Lac strain (a USA300 strain), respectively. These drugs feature an NNSN structural motif, which enables the binding of copper. In the absence of copper, no activity against MSSA and MRSA at realistic drug concentrations was observed. Although none of the novel drug candidates exhibits a stereocenter, sub-micromolar activities against SA Newman and micromolar activities against SA Lac were observed in the presence, but not in the absence, of bioavailable copper. Copper influx is a component of cellular response to bacterial infections, which is often described as nutritional immunity.Methanol and biodiesel are both alternative fuels of diesel engines. In order to study the effects of methanol on the microstructure of particulates produced from the diesel engine fueled with a methanol/biodiesel blend, the methanol/biodiesel blend fuels with 0, 10, and 20% methanol were prepared (named B100, BM10, and BM20, respectively). SEM and TG experiments have been carried out, and the structural and oxidative characteristics of particulates for the methanol/biodiesel blend were investigated. The results showed that the average diameters of B100, BM10, and BM20 particulates were 35, 32.6, and 31.2 nm, respectively. With the increase of methanol blending ratio, the H2O and SOF (soluble organic fraction) contents were increased and the soot content in particulates was reduced slightly. In addition, the activation energy of the particulate pyrolysis reaction was reduced with the increase of methanol mixing ratio, and the oxidative reaction of particulates was easier to carry out.

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