• Journal of the Korean Ceramic Society
• /
• v.43 no.11 s.294
• /
• pp.728-733
• /
• 2006

The equilibrium or growth shape of ceramic materials is classified largely into two categories according to the thermodynamic conditions imposed. One is a polyhedral shape where the surface free energy is anisotropic, and the other a spherical shape where the surface free energy is isotropic. In the case of grains with a polyhedral shape of anisotropic surface free energy, socalled abnormal grain growth usually takes place due to a significant energy barrier for a growth unit to be attached to the crystal surface. In the case of grains with a spherical shape of isotropic surface free energy, however, normal grain growth with a uniform size distribution takes place. In this contribution, the state-of-the-art of our current understanding of the relationship between the crystal shape and the microstructure evolution during the sintering of ceramic materials in the presence of a liquid phase was discussed.

• Nuclear Engineering and Technology
• /
• v.54 no.9
• /
• pp.3478-3487
• /
• 2022

In this study, we incorporate an anisotropic scattering scheme involving spherical harmonics into the method of characteristics (MOC). The neutron transport solution in a light water reactor can be significantly improved because of the impact of an anisotropic scattering source with the MOC flat source approximation. Several problems are selected to verify the proposed scheme and investigate its effects and accuracy. The MOC anisotropic scattering source is based on the expansion of spherical harmonics with Legendre polynomial functions. The angular flux, scattering source, and cross section are expanded in terms of the surface spherical harmonics. Later, the polynomial is expanded to achieve the odd and even parity of the source components. Ultimately, the MOC angular and scalar fluxes are calculated from a combination of two sources. This paper presents various numerical examples that represent the hot and cold conditions of a reactor core with boron concentration, burnable absorbers, and control rod materials, with and without a reflector or baffle. Moreover, a small critical core problem is considered which involves significant neutron leakage at room temperature. We demonstrate that an anisotropic scattering source significantly improves solution accuracy for the small core high-leakage problem, as well as for practical large core analyses.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2008.11a
• /
• pp.5.2-5.2
• /
• 2008

• Proceedings of the Korean Magnestics Society Conference
• /
• 2007.05a
• /
• pp.280.1-280.1
• /
• 2007

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1994.11a
• /
• pp.151-151
• /
• 1994

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1999.11a
• /
• pp.106-106
• /
• 1999

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1997.10a
• /
• pp.101-101
• /
• 1997

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1997.05a
• /
• pp.26-26
• /
• 1997

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1998.11a
• /
• pp.81-81
• /
• 1998

• Journal of the Microelectronics and Packaging Society
• /
• v.17 no.4
• /
• pp.41-48
• /
• 2010

To improve the pot life of one-part in-house anisotropic conductive paste (ACP) formulations, 2-methyl imidazole curing accelerator powders were encapsulated with five agents. Through measuring the melting point of the five agents using DSC, it was confirmed that a encapsulation process with liquid-state agents is possible. Viscosity of ACP formulations containing the encapsulated imidazole powders was measured as a function of storage time from viscosity measurements. As a result, pot life of the formulations containing imidazole powders encapsulated with stearic acid and carnauba wax was improved, and these formulations indicated similar curing behaviors to a basic formulation containing rare imidazole. However, the bondlines made of these formulations exhibited low average shear strength values of about 37% level in comparison with the basic formulation.