Papers by Author: J.R. Martinelli

Abstract: Selective internal radiotherapy is used to treat hepatocellular carcinoma. Glass microspheres containing β^- particle emitter radionuclides are introduced into the liver close to the tumor. The microspheres are trapped in the arterioles which feed the tumor. The irradiation with β^- particles can cause the death of cancer cells. In this work the development of phosphate glass microspheres containing holmium is proposed. ¹⁶⁵Ho has a high cross section for neutron absorption enabling the production of ¹⁶⁶Ho which decays to ¹⁶⁶Er by emitting a β^- particle. The microspheres were produced using the flame method and characterized by different techniques to evaluate their potential use in radiotherapy. Microspheres with suitable morphology, size, density, and holmium concentration were obtained.

Abstract: Cr3C2-NiCr coatings have been used for corrosion and wear resistant applications. In the last decade, thermal sprayed coatings using nanostructured feed stock of other materials has exhibited higher hardness, strength and corrosion resistance. Hence, it is anticipated that nanostructured Cr3C2-NiCr coatings will also exhibit these properties and therefore posses improved performance characteristics. Preparation of nanostructured feed stock powders is the first step in the synthesis of nanostructured coatings and mechanical milling is an effective process to obtain the powders. Preliminary studies in which commercial Cr3C2-NiCr powders were milled in hexane and gaseous nitrogen revealed that particle and crystallite size were significantly smaller in powders milled in nitrogen. This paper presents the effect of hexane content and milling parameters on Cr3C2-Ni20Cr powder characteristics. Use of just sufficient hexane as the milling media reduced significantly the particle and crystallite sizes.