The application of life cycle assessment to metal casting

The thesis presents a Life Cycle Assessment (LCA) study that compares the potential environmental impacts associated with two alternative material groups. The comparison involves aluminium alloy and cast iron automotive casting components. The comparative LCA study aims to identify which system of materials, aluminium or cast iron, reduces the total burdens on the environment most throughout the entire lifecycle of a metal casting automotive application. A specialised LCA software tool (Boustead Model 4.4) has been used to compare and contrast the potential environmental impacts of the two alternative cast metal alloys and, conclusively, identify the best environmental proposition for the specific metal casting application. [Continues.

Post-consumer waste management issues in the footwear industry

Currently, 17 billion pairs of shoes are produced worldwide every year, and this figure continues to rise. This creates an enormous amount of post-consumer (end-of-life) shoe waste that is currently being disposed of in landfill sites around the world. The research reported in this paper is an initial investigation into realization of a holistic approach to application of recovery and recycling in the footwear industry. The paper provides a brief review of the trends in the footwear sector regarding the amount of end-of-life waste produced, together with existing reuse and recycling activities. It also presents an integrated waste management framework by combining a mix of design and material improvements, as well as reuse, recycling, and energy recovery activities, and concludes by examining the challenges in establishing end-of-life product recovery procedures for post-consumer shoes

Characterization of the Core-Shell Nanoparticles Formed as Soluble Hydrogen-Bonding Interpolymer Complexes at low pH

The formation of soluble hydrogen-bonding interpolymer complexes between poly(acrylic acid) (PAA) and poly(acrylic acid-co-2-acrylamido-2-methyl-1-propane sulfonic acid)-graft-poly(N, N dimethylacrylamide) (P(AA-co-AMPSA)-g-PDMAM) at pH = 2.0 was studied. A viscometric study showed that in semidilute solution a physical gel is formed, due to the interconnection of the anionic P(AA-co-AMPSA) backbone of the graft copolymer, in a transient network, by means of the complexes formed between the PDMAM side chains of the graft copolymer and PAA. Dynamic and static light scattering measurements, in conjunction with small angle neutron scattering measurements, suggest the formation of core-shell colloidal nanoparticles in dilute solution, comprised by an insoluble PAA/PDMAM core surrounded by an anionic P(AA-co-AMPSA) corona. Even if larger clusters are formed in semidilute solution, the size of the insoluble core remains practically stable. Atomic force microscopy performed under ambient conditions, reveal that the particles collapse and flatten upon deposition on a substrate, with dimensions close to the ones of the dry hydrophobic core

Oscillatory theorems of a class of even-order neutral equations

AbstractA class of even-order nonlinear neutral differential equations with distributed deviating arguments is studied, and oscillatory criteria for solutions of such equations are established

Are Two Screws Enough for Fixation of Femoral Neck Fractures? A Case Series and Review of the Literature

There is still a controversy in literature regarding the treatment of subcapital fractures of the hip with internal fixation. Different methods have been tested and studies such as in cadavers mainly prejudge the three cannulated screws application. We present a series of 20 patients in which percutaneous fixation with two parallel cannulated screws under specific technical conditions has led to an uneventful fracture union. No complications were observed at a one year follow-up. Reviewing the literature we found no previous clinical studies on the subject