A radically new approach to the in situ synthesis of the consituent phases of a composite structure has enabled the production of a new WC/Co materials with an ultrafine microstructure. The process for synthesizing nanophase WC/Co powders consists of spray drying from solution to form a homogeneous precursor powder, and thermochemical conversion of the precursor powder to the nanophase WC/Co powder. Near theoretical density of pure nanophase WC-10 wt%Co has been obtained in only 30 sec at 140. But WC particles were grown up very rapidly with longer sintering time to get full density. To overcome coarsening of WC particle during sintering, VC, TaC and VC/TaC were used as the grain growth inhibitor with different amount respectively. VC/TaC doped WC-10 wt%Co was shown superior hardness and TRS and microstructure was maintained ultrafine scale (average WC size is less than 0.1 ).

Browse from oriental white oak(Quercus aliena Blume) was analysed for nutritive value and biomass estimation. The content of cmde protein was high on August and September. NDF, ADF and lignin contents were increased with progressing the seasons but IVDMD,

Optimum hypering conditions are found for IIIa-J, IIIa-F, 103a-O, 103a-D, and IIa-O plates using hypersensitization machine in KAO. For every experimental plate we get speed gain, fog increment, signal to noise ratio and relative DQE according to hypering time and temperature. The hypersensitization method is baking with 8% hydrogen mixed gas. For IIIa-J, 103a-O, and 103a-D plates treated 65∘C 65∘C , 3 hours baking, the speed gains arc increased by about 10 times, 2 times, and 2 times compared to untreated plates, respectively. The fogs are increased by 0.08, 0.10, and 0.08, respectively. For IIIa-F, IIa-O plates treated 65∘C 65∘C , 2 hours baking, the speed gains are increased by about 4.7 times and 1.8 times compared to untreated plates, respectively. The fogs are increased by 0.15 and 0.04, respectively.

We have mapped the C 3 H 2 2 12 − 1 01 transition line toward the Sgr A molecular cloud on a 1' grid spacing and derived C 3 H 2 column densities of 3 \~ 7 × 10 14 c m − 2 for molecular clouds of Sgr A. The fractional abundances of C 3 H 2 relative to H 2 are obtained to be 3 \~ 6 × 10 − 9 , which are slightly lower than that for the cold dark cloud TMC-1 but are enhanced by factors of 5-60 compared to those for Sgr B2 and the Orion extended ridge. We also estimate from the C 3 H 2 column densities total masses of \~ 10 6 M ⨀ for two clouds (M - 0.13 - 0.08 and M - 0.02 - 0.07), which are thought to be close to the virial equilibrium. We suggest that the large abundance of C 3 H 2 in Sgr A may be partly due to the activities of the Galactic center.

겉뿌림 산지초지의 조성, 수량, 식생 및 목초품종등에 미치는 3요소(N--O: 0-0-0; 0-10-10; 6-15-15; 12-20-20; 24-25-20 kg/10a/year)와 소석회(0, 250kg/10g; 조성시만 시용)의 시용효과를 구명하는 10년간 시험후, 별도로 토심별 토양의 화학성(I보; pH, OM, T-N, 유효 , 흡수계수, 석회소요량. II보: 치환성 Ca, Mg, K, Na 및 CEC, 염기포화도, 토양보존)을 조사하여 검토하

전라남도 도라지역에 분포하는 개미의 종류와 그의 종조성을 조사할 목적으로 1986년, 1989년, 1990년, 1991년의 4년간 10개 도서의 31개 지역에서 740 colony를 채집하여 동정 한 결과 4아과 30속 54종이 분포하는 것을 확인하였으며, 그 중에 대흑산도 예리에서 채집한 쌍털비늘개미(신칭)와 소안도 맹선리에서 채집된 조개무늬비늘개미(신청)는 한국산 미기록종인 것으로 사료된다. 10개 도라지역에 분포하는 개미의 종조성이 밝혀졌으며 Nomura-Simpson's Coefficient(NSC) 공식에 의한 종류사도를 분석한 바 전라남도 도라지역의 개미상은 연속적이였다

(100) 실리콘 기판에 대해 깊온 비등방성 식각을 행한 경우 식각면의 가장자리에 존재하는 욜균일성은 식각 계면의 격자결함과 기계적 응력에 의한 것임을 판찰할 수 있었다.