In this paper, the corrosion behavior of the filled epoxy paint with the rice husk ash RHA on steel substrates in two different corrosive environments natural sea water and 2M sulfuric acid has been studied. Electrochemical impedance spectroscopy EIS was used to evaluate protective properties of different organic coating systems due to the different filler composition. RHA was prepared by heati...

[3H]Squalene 2,3(S);22(S),23-dioxide was prepared by incubation of [3H]mevalonate with S10 rat liver homogenate in the presence of 4,4,10 beta-trimethyl-trans-decal-3 beta-ol, a specific inhibitor of oxidosqualene cyclase (EC 5.4.99.7). Aerobic incubation of [3H]squalene 2,3(S);22(S),23-dioxide with S10 rat liver homogenate affords 24(S),25-epoxycholesterol with an efficiency comparable to that...

Molecular Dynamics simulations are used to study cross-linking of an epoxy polymer. OPLS force field parameters are used for modeling a 2:1 stoichiometric mixture of epoxy resin and the cross-linking agent. The model has 17,928 united atoms and a static cross-linking method is used along with molecular minimization and molecular dynamics techniques to achieve two different cross-link densities....

A simple measurement system is described for evaluating damage to graphite-epoxy panels, such as those used in high-performance aircraft. The system uses a heating laser and infrared imaging system to measure thermal performance. Thermal conductivity or diffusivity is a sensitive indicator of damage in materials, allowing this thermal measurement to show various degrees of damage in graphite-ep...

For the first time, repeatable self-healing was achieved in a cross-linked epoxy polymer by incorporating 2-ethyl-4-methylimidazole (24-EMI) into the matrix as a latent polymerization initiator. Upon material damage and infiltration of liquid EPON 8132 epoxy monomer healing agent into the crack plane, polymerization occurs in the damaged region with a moderate application of heat in the presenc...

Plastic deformation in the form of slip lines is observed in front of notches in pure epoxy and robber-toughened epoxy specimens under four-point bending. In contrast to the case for pressure-insensitive materials, the angles between two families of slip lines emanating from notch surfaces are not 90°: they are smaller than 90 ° under tension, but they are larger than 90 ° under compression. Fo...

The use of epoxy resins in metal structures for adhesive reasons is getting wider. Epoxy resins possess enhanced mechanical, chemical and physical properties, i.e. increased shear and compression strength, resistance in solvents, as well as at high temperatures. Tensile tests were carried out with standard aluminium tension specimens glued with epoxy resins. The thickness of the glue and the ac...

A series of metal-containing epoxy polymers have been synthesized by the condensation of epichlorohydrin (1-chloro-2,3-epoxy propane) with Schiff base metal complexes in alkaline medium. Schiff base was initially prepared by the reaction of 2,6 dihydroxy 1-napthaldehyde and o-phenylenediamine in 1 : 2 molar ratio and then with metal acetate. All the synthesized compounds were characterized by e...

A reaction of methyl (4R,5R)-4,5-epoxy-2(E)-hexenoate 1 with N-benzylmethylamine gave a diastereomerically pure methyl (4R,5R)-4,5-epoxy-(3S)-N-benzylmethylamino hexanoate 6 and methyl (4S,5R)-4-N-benzyl-methylamino-5-hydroxy-2(E)-hexenoate 7. The former was chemoenzymatically converted to (-)-osmundalactone 11, which is an aglycone of osmundalin. On the other hand, the directly conjugated addi...