Thermal effects in high density polyethylene and low density polyethylene at high hydrostatic pressures

The temperature changes as a result of rapid hydrostatic pressure applications are reported for high density polyethylene (HDPE) and low density polyethylene (LDPE) in the reference temperature range from 298 to 423 K and in the pressure range from 13.8 to 200 MN m −2 . The adiabatic temperature changes were found to be a function of pressure and temperature. A curve fitting analysis showed that the empirical curve (∂/∂ P ) = ab (Δ P ) b−1 described the experimental thermoelastic coefficients obtained from the experiments. The data were analyzed by determining the predicted thermoelastic coefficients derived from the Thomson equation (∂/∂ P ) θ = α T 0 /ϱ C p . The experimental and predicted Grüneisen parameter γ T were also determined.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44687/1/10853_2005_Article_BF01132919.pd

Fracture behaviour of unmodified and rubber-modified epoxies under hydrostatic pressure

The fracture toughness and uniaxial tensile yield strengths of unmodified and CTBN-rubber-modified epoxies were measured under hydrostatic pressure. The purpose of these experiments was to learn how suppressing cavitation in rubber particles affects the deformation mechanisms and the fracture toughness of rubber-modified epoxy. It was found that the cavitation of CTBN-rubber could be suppressed at a relatively low pressure (between 30 and 38 M Pa). With cavitation suppressed, the rubber particles are unable to induce massive shearyielding in the epoxy matrix, and the fracture toughness of the rubber-modified epoxy is no higher than that of the unmodified epoxy in the pressure range studied. Unmodified epoxy shows a brittle-to-ductile transition in fracture toughness test. The reason for this transition is the postponement of the cracking process by applied pressure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44734/1/10853_2005_Article_BF01154701.pd

Determining Shapes and Sizes Using TEM Images: Functionalized Nanoparticles

none7siFunctionalized nanoparticles to be used for drug delivery must undergo specific verifications in accordance to preestablished requirements. Acquiring TEM (transmission electron microscopy) imaging dealing with nanoparticles functionalization, it is possible to encounter possible faults in the shape of the nanoparticles due to surplus of materials or loss in doses of the materials. Even if the functionalizing instrumentation is equipped with dedicated systems acting accordingly, a further 'check and balance' process could be useful using for instance imaging. The paper illustrates the application of an optimized and automatic segmentation technique for determining shapes and sizes the aforementioned nanoparticles.restrictedLay-Ekuakille A.; Di Paola M.; Conversano F.; Casciaro S.; Sommella P.; Liguori C.; Bhateja V.Lay-Ekuakille, A.; Di Paola, M.; Conversano, F.; Casciaro, S.; Sommella, P.; Liguori, C.; Bhateja, V

Determining Shapes and Sizes Using TEM Images: Functionalized Nanoparticles

Functionalized nanoparticles to be used for drug delivery must undergo specific verifications in accordance to preestablished requirements. Acquiring TEM (transmission electron microscopy) imaging dealing with nanoparticles functionalization, it is possible to encounter possible faults in the shape of the nanoparticles due to surplus of materials or loss in doses of the materials. Even if the functionalizing instrumentation is equipped with dedicated systems acting accordingly, a further 'check and balance' process could be useful using for instance imaging. The paper illustrates the application of an optimized and automatic segmentation technique for determining shapes and sizes the aforementioned nanoparticles

Advanced imaging processing for extracting dynamic features of gas turbine combustion chamber

Many industrial and transportation applications use combustion in dedicated chambers. Combustion implies, depending upon the nature and the amount of precursors, production of carbon dioxide, pollutants and dusts in terms of particulate matters. With the aim of reducing emission, lean combustion is of great interest. However flame stability within the combustor chamber is a key issue under lean conditions. In fact under lean conditions burners exhibit flame instability, flashback or lean blow out, until the flame extinction. Hence the online monitoring of these phenomena related to combustion instability is essential. One the most used techniques is to check temperature and flame stability by means of sensing probes resisting to high temperatures. Increasing the number of probes, it is possible to perform a 2D and 3D monitoring. However since these probes are costly and require heavy maintenance procedures, it could be wise to exploit imaging processing through cameras directed to portholes across which we can see inner parts, and atmosphere of the furnace/chamber. This paper illustrates findings related to monitoring the flame behaviour different operating conditions chamber by an advanced image processing. A specific algorithm has been developed to characterize the flame, hence, to perform measurements. Myriad filters have been utilized to enhance flame features