• 한국세라믹학회지
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• 제34권4호
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• pp.413-419
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• 1997

The specimens which were prepared from cokes with additions of 0~25 wt% B4C were sintered in Ar atmosphere at 220$0^{\circ}C$. The effects of B4C content on graphitization and oxidation resistance of cokes were investigated. B4C accelerates the graphitization of cokes and at 220$0^{\circ}C$ the degree of graphitization increased from 0.33 which is the value of pure carbon to 0.56, which increased bluk density and porosity. Especially bending strength increased as th graphitization temperature increased. Oxidation resistance property was greatly improved when B4C was added more than 10wt% at 80$0^{\circ}C$ and when B4C was added more than 20wt% at 100$0^{\circ}C$. This was because that the thin layer of B2O3 glass phase on the surface of the composite could be identified to increase the oxidation resistance.

• Nuclear Engineering and Technology
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• 제29권4호
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• pp.299-309
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• 1997

The neutronic feasibility of typical Korean three-loop 900MWe class PWR core loaded with mixed oxide fuels for both annual and 18-month cycle strategies has been investigated as a means for spent fuel management. For this study, a method of determining equivalent plutonium content was developed under the equivalence concept which gives the same cycle length as uranium fuel. Optimal plutonium zoning within the MOX assembly was also designed with the aim of minimizing the peak md power. Conceptual core designs hate hen developed for equilibrium cycle with the following variations: annual and 18-month cycle, 1/3 and full MOX loading schemes, and typical and high moderation lattice. The analysis of key core physics parameters shows that in all cases considered satisfactory core designs seem to be feasible, though addition of control rod system and change in Technical Specification for soluble boron concentration are required for full MOX loading in order to meet the current design requirements.

• 한국표면공학회지
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• 제32권2호
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• pp.172-181
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• 1999

The effect of the DMAB concentration, temperature, deposition time, and stabilizer concentration on the precipitation reaction of the electroless nickel plating using dimethylamine borane (DMAB) as reducing agent was investigated to by the weight gain and electrochemical method. The deposition rate was dependent with DMAB concentration. The polarization resistance of the precipitation reaction was reduced with DMAB concentration. The precipitation reaction rate of Ni-B deposits was controlled by the oxidation rate of DMAB as the source of electron. The boron content of the deposit was constant at about 5.5wt%, even when DMAB concentration in the solution was increased. The effect of temperature and stabilizer ($Pb(NO_3)_2$) concentration on deposition rate was shown to have co-dependent behaviors.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1033-1034
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• 2006

Metallic compound of ternary Al-B-C system was prepared by mechanical alloying (MA) using Al, boron and graphite powders as starting materials. MA was carried out using Spex 8000 mixer/mill for 50 hours in an argon atmosphere without process control reagent such as methyl alcohol. The MA powders obtained were heat-treated in vacuum at the temperature of 873 and 1273 K for 5 hour. Pure ternary Al-B-C compound was obtained in the chemical content of Al:B:C=55:27:18. The ternary compound obtained in this study has a new phase whose crystal structure is not identified yet.

• Carbon letters
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• 제5권3호
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• pp.113-117
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• 2004

The mesophase pitch was prepared by adding 1~10 wt% of the borane-pyridine complex (BPC) to decant oil. It was prepared in a reactor held at $450^{\circ}C$ for 2 h in $N_2$ atmosphere. The mesophase pitches were analyzed using thermogravimetric analyzer (TGA), melting point apparatus, X-ray diffraction (XRD) and polarized optical microscope. The coke yield, softening point, toluene insoluble, density and content of anisotropy in the mesophase pitches were increased with BPC contents. The XRD profiles did not show any effect of addition of BPC on the formation of mesophase pitch, while the crystallinity of mesophase pitches was increased when the materials were heat treated with boron compound.

• 마이크로전자및패키징학회지
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• 제6권4호
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• pp.35-39
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• 1999

The $Li_2O-MgO-MgF_2-SiO_2$glasses with addition of $B_2O_3$ were investigated in order to make glass-ceramics for low temperature firing substrate. Glasses were made by melting at $1450^{\circ}C$ in the electronic furnace and crystallized at $750^{\circ}C$. The crystal phases were polycrystalline of lithium boron fluorphlogopite and lithium fluorhectorite. The crystal shape was chanced to granule type from needle type with increasing $B_2O_3$ content. Average particle size of the glass-ceramics after water swelling was 3.77$\mu\textrm{m}$. The optimum sintering temperature and sintering shrinkage of the substrate were $900^{\circ}C$ and 13.4%, respectively.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.79-80
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• 2019

This study was intended to examine the possibility of reducing hydration heat by FA substitution and combination of slag (CGS) from coal gasification power generation (IGCC) with mixed aggregate for concrete. The analysis results showed good results if liquidity increases as the ratio of CGS increases, air volume decreases, and compressive strength is mixed up to 25% in the residual aggregate. The results showed that the heat of hydration was reduced compared to plain due to the boron content of CGS as the CGS substitution rate increased, but it was larger due to the combination with FA substitution. It was found that the heat of hydration was reduced.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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• pp.52-57
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• 1996

The coolant void reactivity is positive for CANDU reactor loaded with DUPIC fuel which has more fissile content compared to natural uranium. A parametric study was done to reduce the void reactivity of the fuel bundle and loss in discharge burnup was estimated. It is observed that the burnable absorbers like gadolinium, boron, europium are not able to keep the reduction in void reactivity uniform throughout fuel burnup. Dysprosium and erbium can keep the void reactivity reduction uniform throughout. fuel burnup but toss in discharge burnup for erbium case is more compared to that of dysprosium case.

• 한국환경농학회지
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• 제17권3호
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• pp.189-194
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• 1998

토양반응이 산성이고 붕소함량이 낮은 사양질 밭에서 토양개량제로 석탄회와 석고, 패각을 석탄회80, 패각4, 석탄회56+석고24, 석탄회40+석고24+패각0.8ton/㏊ 수준으로 시용하고 가을배추 재배에 이어서 2년차 봄배추를 재배하여 배추생육과 품질에 대한 시용잔효를 검토하였다. 개량제 시용에 따른 배추의 수확물은 대조구의 8.7ton/㏊을 기준으로 석탄회+석고+패각 혼용구에서 834%, 석탄회+석고 혼용구에서 786%, 석탄회 단용구에서 755%, 패각 단용구에서 193% 증가하였다. 수확된 배추체내 환원당과 비타민-C, 전질소 함량은 처리별 수량 성적 경향과 일치하였고 조섬유는 반대경향을 보였다. 또한 석탄회가 시용된 구에서는 개량제 무시용구 및 패각단용구를 달리 붕소결핍증이 없었고 유해 중금속의 식물체 잔류량이 감소되거나 자연함량 이하였다. 그리고, 이들 토양개량제를 상용할 경우에는 작물의 균형있는 양분흡수를 위해 3요소비료와 함께 마그네슘을 별도 시용하는 것이 바람직할 것으로 생각되었다.

• 한국토양비료학회지
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• 제30권2호
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• pp.161-167
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• 1997

석탄 화력발전소에서 생산되는 석탄회를 비료자원 및 토양 개량제로 활용하기 위한 기초자료를 얻기 위해서 배추를 공시작물로 하여 석탄회(유연탄회, 무연탄회)를 수준별(5%, 10%, 15%)로 시용하고 배추의 생육 및 수량, 식물체중 무기성분 함량, 토양의 이화학적 성질에 미치는 영향 등을 조사한 결과를 요약하면 다음과 같다. 1. 석탄회의 화학적 조성은 알칼리성 물질로서 규소와 알루미늄을 75%($SiO_2$:50.3-54.7%, $Al_2O_3$:21.9-25.3%)이상 함유하고 있어 규산염광물과 유사한 특성을 지니며, 작물생육에 필요한 여러 가지 다량원소(인산, 가리, 석회, 고토) 및 미량원소(붕소, 동, 아연, 철, 망간)를 함유하고 있었으며, 인산, 석회, 고토 등은 유연탄회에서, 가리, 붕소 함량등은 무연탄회에서 높았다. 2. 배추의 생체수량은 무시용구인 대조구보다 석탄회 시용으로 유의한 수량 증가를 보였으며, 석탄회 종류별로 볼 때 유연탄회는 최고 시용수준인 15%, 무연탄회는 시용수준 10%에서 최고수량을 보였으나 유연탄회 및 무연탄회 공히 시용수준간에는 유의한 수량차이가 없었다. 3. 수확기 식물체중 대부분의 무기성분 함량은 석탄회 시용으로 감소하였으나, 붕소 함량만은 증가하였다. 석탄회 종류별로 보면 유연탄회 시용량에 따라 질소, 인산, 석회 등이, 무연탄회의 경우에는 질소, 인산 등이 증가하였다. 4. 토양중 무기성분 함량은 대조구에 비해 유연탄회 시용으로 토양의 pH와 인산, 석회, 고토, 아연, 동 및 붕소 함량이, 무연탄회 시용은 토양의 pH와 인산 및 붕소 함량이 높은것으로 보아 토양산도의 교정효과와 함께 이들 성분에 대한 잔효가 기대된다. 5. 수확기 식물체중 크롬, 카드뮴, 납 등의 함량과 시험후 토양중 카드뮴 함량은 유연탄회나 무연탄회의 시용에 관계없이 흔적으로 나타났으나, 크롬 및 납 등의 함량은 유연탄회 및 무연탄회 모두 미량으로 함유되어 있었다.