This paper establishes an infrared spectral identification key for five natural resins (shellac, sandarac, mastic, copal and rosin) based on their absorbance band positions. These resins may be identified when used in mixtures, such as furniture finishes, at concentrations as low as 1%. Computer methods of deconvolution and spectral subtraction are used to augment this process. The method was v...

A new analytical approach to optimize the thicknesses of a two-layer absorbing structure constituted by graphene-based composite and polymer dielectric spacer backed metallic layer acting as perfect electric conductor (PEC) is proposed. The lossy sheet made an epoxy-based vinyl ester resin filled with graphene nanoplatelets (GNPs) characterized known frequency spectra complex permittivity. opti...

Epoxy – Polysulfide copolymers without or with low amounts of epoxy in their structure have poor mechanical properties in oxidative curing system.To strengthen the mechanical properties of polysulfide elastomer inclusion of epoxy resin (Epon828) as hard segment was studied. FT-IR spectroscopy and rheometry were used to verify the formation of epoxy-polysulfide copolymer.  Results obtained f...

The energy release rate for propagation of a debond in either a single-fiber pull-out test or a microbond test was derived analytically. The key finding was that an accurate analysis can be derived by a global energy analysis that includes effects of residual stresses and interfacial friction but does not need to include the details of the stress state at the interfacial crack tip. The analytic...

The current route in the UK for the conditioning and immobilization of most intermediate level waste for interim storage and geological disposal is to encapsulate in a cementitious matrix. However, certain waste materials, such as those containing reactive metals (e.g. uranium and aluminium), can corrode in the presence of the highly alkaline water in a cementitious environment. In their initia...

Chemical exfoliation of graphite under strong oxidizing conditions yields graphene oxide nanosheets with oxy functional groups on the carbon basal plane. The importance of ozone in the chemical oxidation mechanism of graphite by the widely-used Hummers' method has been largely overlooked. Herein we demonstrate that the ozonolysis of graphite leads to the formation of secondary epoxy and peroxym...

This paper investigated the effect of the amine-functionalized carbon nanotubes (CNTs) on the thermomechanical properties of CNT/epoxy nanocomposites. Mechanical stirring and ultra-sonication were utilized to uniformly disperse CNTs into the epoxy matrix. Non-functionalized and amine-functionalized CNTs with different weight percentages (wt. %) were mixed into the epoxy resin. Using standard te...

epoxy – polysulfide copolymers without or with low amounts of epoxy in their structure have poor mechanical properties in oxidative curing system.to strengthen the mechanical properties of polysulfide elastomer inclusion of epoxy resin (epon828) as hard segment was studied. ft-ir spectroscopy and rheometry were used to verify the formation of epoxy-polysulfide copolymer.  results obtained from ...

This study concerns a 69-year-old female patient with a longstanding history of venous ulcerations on both lower legs and multiple sensitivities, who developed eczematous lesions with the hydrocolloid dressing Combiderm (Convatec Ltd., a Bristol-Myers Squibb division, Ickenham, Middlesex, UK). Epicutaneous tests were positive to this dressing and to a modified colophonium derivative, i.e. glyce...