In this work, effect of various process-control agents (PCAs) on the mechanical alloying of amorphous alloy of has been investigated. The dependence of the particle shape, size and crystallization behavior of the amorphous alloy powders on the type of PCAs and their concentrations was investigated by using X-ray diffraction, field-emission scanning electron microscopy and differential scanning calorimetry. It was found that the additive of toluene could affect positively the amorphization and thermally induced crystallization processes, as well as the size refinement, morphology and particle-size distribution of as-milled powders in comparison with alloy obtained without PCA.

TiCuNiAl quaternary amorphous alloy was prepared by high-energy ball milling process. A complete amorphization was confirmed for the composition of TiCuNiAl after milling for 30hrs. Differential scanning calorimetry showed a large super-cooled liquid region (T = T T, T and T: glass transition and crystallization onset temperatures, respectively) of 80 K. Prepared amorphous powders of TiCuNiAl were consolidated by spark-plasma sintering. Densification behavior and microstructure changes were investigated. Samples sintered at higher temperature of 713 K had a nearly full density. With increasing the sintering temperature, the compressive strength increased to fracture strength of 756 MPa in the case of sintering at 733 K, which showed a 'transparticle' fracture. The samples sintered at above 693 K showed the elongation maximum above 2%.

We have studied the response of molecular clouds in the Galactic disk to a rotating bar by conducting Smoothed Particle Hydrodynamics (SPH) simulations for the Galaxy in order to understand the dynamical structures of the Galactic Center (GC) molecular clouds, and their implications. In our study it was found that the structures of GC molecular clouds could be induced by the combined effects of rotating bar potential, the hydrodynamic collisions and gravitational miss collisions between the clouds.

본 연구는 야생콩과 재배콩의 교잡 후대 집단에서 25계통을 선발하여 사료 수량 및 품질을 평가하여 사료용 콩 품종육성 가능성을 검토하였으며, 그 결과를 요약하면 다음과 같다. 먼저, 야생콩과 재배콩 교잡종의 조사료 수확시기별 수량 및 품질 검정에서 교잡종을 대조품종인 재배콩과 비교하여 보았을 때 사료의 수량이나 품질을 고려하면 협비대기인 R6에 가장 우수한 것으로 평가가 되었다.야생콩과 재배콩의 교잡후대 계통에 대한 사료 수량 및 품질평가에서 대조품종과 비슷하거나 유의적인 차이가 없는 수량이 높은 계통을 선발할 수 있었으며, 가식부위 생체중은 대조품종인 재배콩 보다 교잡종이 상대적으로 높은 것으로 평가가 되었다. 교잡종에 대한 사료품질을 평가한 결과 AFGC의 두과 건초 품질 등급기준에 따라 나누었을 때, 특등급의 조건인 조단백질 함량 19% 이상, NDF 함량 40% 미만, ADF 함량 31% 미만, DDM 65% 이상, DMI 3.0% 이상, RFV 151 이상을 모두 충족시키는 계통을 선발할 수 있었고, 이들중 몇몇 계통은 수량도 우수한 것으로 평가가 되었다. 따라서, 재배콩과 야생콩의 교잡을 통해 사료 수량 및 품질이 우수한 사료용 콩을 개발할 수 있을 것으로 판단된다.