Evaluation of greenhouse residues gasification performance in hydrogen production

In this study, a modeling study was carried out to investigate the potential of hydrogen production from greenhouse tomato and pepper residues blending in different rates (0%, 25%, 50%, 75% and 100%) by air-steam gasification. The numerical model developed for the gasification system assumes that all carbon in the mixture is gasified. Air to fuel rate and steam to fuel rates are 0.05 due to high content of O₂ in biomass residues. The gasifier temperature is 877 °C (1150 K) for developed model. According to the result of this study, increasing tomato residues blending rate increases hydrogen content of syngas. It is mainly caused by the content of O₂ in tomato residues being higher than content of O₂ in pepper residues. This study shows that the O₂ content of greenhouse residues is an important factor in syngas production, especially in H₂ production.     

Angle of Hertzian Cone Cracks

This paper discusses the difference between the experimentally observed angle of Hertzian cone cracks and the angle defined by the trajectories of the preexisting stress fields. It is argued that there is no reason why these angles should be the same, as has usually been assumed. A finite element method has been used to model the growth of cracks in the Hertzian stress fields. In this model, the crack is incrementally advanced along the direction of maximum strain energy release, as calculated by the evolving, rather than the preexisting, stress fields. For the modeled Hertzian indentation system, a cone crack is observed to grow, but at an angle which is significantly different from that defined by the normal to the maximum preexisting tensile stress. The angle of the cone crack, as grown in the model, is in excellent agreement with observations on experimentally grown cone cracks in glass, with the same Poisson's ration. It is proposed that, in general, cracks will grow along paths that result in the maximum release of strain energy. For asymmetric, nonuniform preexisting stress fields, such paths do not necessarily coincide with the normal to the maximum preexisting tensile stress.     

Polymeric antimicrobial N-halamine epoxides

A new N-halamine copolymer has been prepared, characterized, and evaluated for antimicrobial efficacy, stability toward hydrolyses, and stability toward UVA degradation when covalently bound to cellulose fibers. A copolymer of 3-chloro-2-hydroxypropylmethacrylate and glycidyl methacrylate was coated onto cotton, and, after curing, was treated with an aqueous solution containing the potassium salt of 5,5-dimethylhydantoin to form a coating which became antimicrobial upon exposure to househod bleach (sodium hypochlorite). The coating inactivated S. aureus and E. coli O157:H7 within minutes of contact time and was quite stable toward washing and UVA photodegradation.     

N-halamine copolymers for use in antimicrobial paints

A series of copolymers containing units of a novel hydantoinylacrylamide and the sodium salt of 2-(acrylamido)-2-methylpropanesulfonic acid have been synthesized. The homopolymer of the hydantoinylacrylamide compound was insoluble in water, while the copolymers with the sulfonic acid sodium salt were water-dispersible/soluble, with the solution becoming completely transparent when the feed ratio for the copolymer contained 7 parts of the hydantoin moiety to 3 parts of the sodium sulfonate moiety. The polymers were added into a commercial water-based latex paint, and upon drying, the painted surfaces treated with the water-miscible copolymers were rendered antimicrobial following chlorination with dilute household bleach. The chlorinated homopolymer failed to provide an antimicrobial property for the paint because of its tendency to isolate into aggregates in the paint, while the completely miscible copolymers were capable of 6-log inactivation of Staphylococcus aureus and Escherichia coli O157:H7 within 5 min of contact time.     

Antimicrobial polyester

Two N‐halamine siloxane precursors, 5,5‐dimethyl‐3‐(3′‐triethoxysilylpropyl)hydantoin and 3‐(3′‐triethoxysilylpropyl)‐7,7,9,9‐tetramethyl‐1,3,8‐triazaspiro[4.5]decane‐2,4‐dione, have been synthesized and coated onto polyester fiber surfaces. The coated polyester was rendered biocidal after exposure to household bleach solution by converting the heterocyclic precursors to N‐halamine moieties. The thermal properties of these coated polyester samples were determined with differential scanning calorimetry. The chlorinated polyester swatches were challenged with Staphylococcus aureus (ATCC 6538) and Escherichia coli O157 : H7 (ATCC 43895) with contact times ranging from 1 to 30 min. The biocidal testing showed that the chlorinated samples inactivated S. aureus and E. coli O157 : H7 within 5 and 30 min of contact, respectively. Standard washing tests indicated that the chlorinated coated fibers were very resistant to loss of the coating through hydrolyses. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

N‐(hydroxymethyl) acrylamide as a multifunctional finish to cotton and a tether for grafting methacrylamide for biocidal coatings

N‐(hydroxymethyl) acrylamide (NMA) was immobilized on cotton surfaces through etherification, and then methacrylamide (MA) was grafted onto the treated surface. The coatings were characterized by ATR‐IR spectroscopy and were rendered biocidal upon exposure to dilute household bleach. The treated fabrics were challenged with Gram‐negative and Gram‐positive bacteria; both NMA and NMA/MA‐treated fabrics inactivated about 8 logs of Escherichia coli O157:H7 and Staphylococcus aureus within only 5 min of contact time. The coatings were also quite stable toward ultraviolet (UVA) light exposure and repeated laundering. Moreover, a substantial improvement in wrinkle recovery angle was obtained for the NMA/MA‐treated fabrics. The new acyclic acrylamide N‐halamine coating should be less expensive to produce and use than previous cyclic N‐halamine coatings developed in these laboratories. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Thermodynamic re-assessment of the Al–Ir system

The thermodynamic assessment of the Al–Ir binary system was performed using the CALPHAD technique. The B2-AlIr phase was described, using the two sublattice model with the formula (Al,Ir,V a)_1/2(Al,Ir,V a)_1/2, while Al₉Ir₂, Al₃Ir, Al₁₃Ir₄, Al₄₅Ir₁₃, Al₂₈Ir₉, and Al_2.7Ir compounds were treated as stoichiometric compounds. The fcc-based phases (L1₀-AlIr, L1₂-Al₃Ir, L1₂-AlIr₃ and A1) were described using the four sublattice model with the formula, (Al,Ir)_1/4(Al,Ir)_1/4(Al,Ir)_1/4(Al,Ir)_1/4. From ab initio calculations (VASP) the formation enthalpies of the stable/metastable intermetallic phases involved in the Al–Ir system were estimated. The thermodynamic quantities, such as the phase equilibria, invariant reactions, and formation enthalpies of the intermetallic phases, were calculated using the obtained parameter set, and agree well with experimental data.     

Multifunctional cotton fabric: Antimicrobial and durable press

2‐Amino‐2‐methyl‐1‐propanol (AMP) was coated onto cotton fabric with 1,2,3,4‐butanetetracarboxylic acid (BTCA) as a crosslinking agent to simultaneously impart antimicrobial and durable‐press functionalities. The coatings were characterized and confirmed by attenuated total reflectance–IR and thermogravimetric analysis. The coated fabrics were rendered biocidal upon exposure to dilute household bleach, and the chlorinated swatches exhibited about 6 log reductions of Escherichia coli O157:H7 and Staphylococcus aureus within 5 min of contact time. A concentration of 1.5 wt % AMP was sufficient to produce this biocidal efficacy. Increasing the BTCA content of the coating improved the wrinkle recovery angle. The coatings were very stable toward repeated laundering, and they exhibited sufficient halogen storage stabilities for industrial applications. A photolytic decomposition was observed when the coatings were exposed to UVA light. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The Sodium-Glucose Cotransporter-2 Inhibitor Canagliflozin Alleviates Endothelial Dysfunction Following In Vitro Vascular Ischemia/Reperfusion Injury in Rats

Vascular ischemia/reperfusion injury (IRI) contributes to graft failure and adverse clinical outcomes following coronary artery bypass grafting. Sodium-glucose-cotransporter (SGLT)-2-inhibitors have been shown to protect against myocardial IRI, irrespective of diabetes. We hypothesized that adding canagliflozin (CANA) (an SGLT-2-inhibitor) to saline protects vascular grafts from IRI. Aortic rings from non-diabetic rats were isolated and immediately mounted in organ bath chambers (control, n = 9–10 rats) or underwent cold ischemic preservation in saline, supplemented either with a DMSO vehicle (IR, n = 8–10 rats) or 50µM CANA (IR + CANA, n = 9–11 rats). Vascular function was measured, the expression of 88 genes using PCR-array was analyzed, and feature selection using machine learning was applied. Impaired maximal vasorelaxation to acetylcholine in the IR-group compared to controls was significantly ameliorated by CANA (IR 31.7 ± 3.2% vs. IR + CANA 51.9 ± 2.5%, p < 0.05). IR altered the expression of 17 genes. Ccl2, Ccl3, Ccl4, CxCr4, Fos, Icam1, Il10, Il1a and Il1b have been found to have the highest interaction. Compared to controls, IR significantly upregulated the mRNA expressions of Il1a and Il6, which were reduced by 1.5- and 1.75-fold with CANA, respectively. CANA significantly prevented the upregulation of Cd40, downregulated NoxO1 gene expression, decreased ICAM-1 and nitrotyrosine, and increased PECAM-1 immunoreactivity. CANA alleviates endothelial dysfunction following IRI.