896 research outputs found
Syntheses and Evaluation of Phthalocyanine Derivatives for Applications in Photodynamic and Boron Neutron Capture Therapies for Cancer
Chapter I introduced the background of phthalocyanines including its physical properties and various synthetic methods of free-base and metallo-phthalocyanines. The background of PDT and BNCT was introduced and the objective of ideal sensitizers was described. Chapter II described the synthesis and characterization of a series of pyridiloxy-substituted zinc phthalocyanines with different length of alkyl groups. Pyridiloxy-substituted silica phthalocyanines bearing different associated axial ligands, were alkylated with methyl or PEG chains. Biological study was performed on these cationic pyridiloxy-substituted zinc phthalocyanines. Chapter III introduced the synthesis and photophysical properties of A3B-type zinc phthalocyanines conjugated with one or two cobalta-carborane cages. They are highly soluble in polar solvents such as methanol, acetone, DMF and DMSO. Their absorption and emission properties are solvent-dependent, and had ~0.1 fluorescence quantum yields. These Pcs may have potential application as dual sensitizers in the PDT and BNCT treatment of tumors. Chapter IV introduced the synthesis and characterization of octa, tetra and dihdroxy-substituted phthalocyanines using different synthetic strategies. Chapter V introduced the synthesis and characterization of octaphosphonate-substituted zinc phthalocyanine
Modeling of convective heat transfer coefficient of graphite foam and effective young\u27s modulus of short fiber-reinforced composite
The present work can be divided into two parts: (1) the analytical modeling on the overall convective heat transfer coefficient of porous graphite foam, developed at the Oak Ridge National Laboratory, and (2) the finite element analysis on effective Young\u27s modulus of short fiber-reinforced composite. The present efforts focus on the relationship between the vital microstructural parameters (e.g., pore size, porosity, fiber aspect ratio, etc.) and overall properties (eg, convective heat transfer coefficient and effective Young modulus) of novel graphite foams and discontinuous fiber-reinforced composites
The graphite foam developed at the Oak Ridge National Laboratory is a promising candidate for the core material in heat exchangers. To develop graphite foams that exhibit high thermal conductivities, high convective heat transfer coefficients, and acceptable pressure drop across the foam, one must have a clear delineation of the interaction between overall properties and foam microstructure, which in turn, is related to the processing of foam. To this end, an analytical model is developed to explicitly include vital microstructural parameters such as foam porosity and pore size, and properties and free stream velocities of cooling fluids, and to predict the overall convective heat transfer coefficient as well as pressure drop of the graphite foam. The predictions agree well with experimental results.
Not a lot of analytical models are available for estimating the effective properties and the stress transfer in short fiber-reinforced or whisker composites. The most popular ones are shear-lag based models The validity of the predicted effective Yung moduli of short fiber-reinforced composites obtained by the modified shear-lag model is verified by the present finite element analysis In particular, the effects of fiber volume fraction and fiber aspect ratio on the effective Young modulus of short fiber-reinforced composite are examined. It is concluded that the modified shear-lag model generally provides very accurate estimates on effective longitudinal Young\u27s moduli of short fiber- reinforced composite
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