• Weed & Turfgrass Science
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• 제4권2호
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• pp.144-150
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• 2015

규산질 비료는 잔디에 있어서 생육과 밀도 향상 효과가 인정되고 있다. 대부분 슬래그 규산질 비료를 사용하고 있지만 최근에는 수용성 규산염을 원료로 한 규산질 등이 개발되어 시판되고 있다. 본 연구에서는 수용성 규산염에 대한 연구가 미흡한 실정으로 수용성 규산 시용에 따른 한국 잔디의 생육과 토양화학성 변화를 알아보고자 수용성 규산($SiO_2$) 함량별 처리 후 와그너포트 시험과 잔디 재배지 포장시험을 수행하였다. 수용성 규산 무처리구에 비해 수용성 규산 함량이 높을수록 근장, 지상부와 포복경의 생체중과 건물중, 한국잔디의 밀도가 유의성 있게 증가하였으며, 식물체내 조규산 함량은 유의하게 증가하였으나 토양 화학성에는 유의한 차이가 없었다. 수용성 규산 함량 18과 $36{\mu}lml^{-1}$ 처리구간의 유의한 차이가 크지 않아 적정 수용성 규산 함량은 $18{\mu}lml^{-1}$으로 판단되었고, 식물체 내 조규산의 공급원으로서 수용성 규산을 토양에 직접시비보다는 엽면시비로 한국잔디의 생장에 기여할 수 있을 것으로 판단된다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.676-678
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• 2004

In order to develop new yellow phosphor that emit efficiently under the 450 - 470 nm excitation range, we have synthesized a $Eu^{2+}$-activated $Sr_3SiO_5$ yellow phosphor and investigated an attempt to develop white LEDs by combining it with a InGaN blue LED chip (460 nm). Two distinct emission bands from the InGaN-based LED and the $Sr_3SiO_5$:Eu phosphor are clearly observed at 460 nm and at 570 nm, respectively. These two emission bands combine to give a spectrum that appears white to the naked eye. Our results showed that InGaN (460 nm chip)-based $Sr_3SiO_5$:Eu exhibits a better luminous efficiency than that of the industrially available product InGaN (460 nm chip)-based YAG:Ce.

• 한국안광학회지
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• 제3권1호
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• pp.217-222
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• 1998

$SiO_2-TiO_2-AgO$ 코팅박막을 졸-겔법으로 현미경용 슬라이드 유리판과 씰리콘 기판에 제조하였다. 이 박막의 열처리온도는 $500^{\circ}C$가 적절하였으며 5회 반복코팅한 박막의 두께는 310nm였다. AgO가 10mol% 첨가된 박막의 표면은 균일한 구조를 보였으나 첨가량이 많아질수록 박막의 표면에 pin hole과 AgO의 석출에 기인한 cluster를 보였다. 열처리온도의 증가에 따라 IR흡수의 정도가 점차 감소하였고, AgO 첨가량의 증가에 따라 반사율은 점차 감소하였으며 색상은 light yellow에서 무채색 쪽으로 점차 전이하였다.

• 한국세라믹학회지
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• 제15권4호
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• pp.199-204
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• 1978

In the present investigation, refined alumina obtained from alunite locally available was used as a aluminous source to synthesize monocalcium aluminate $(CA)_3$ the major mineral constituent of alumina cement. The influence of $SiO_2$ and $Fe_2O_3$ contents on the formation of monocalcium aluminate was studied by X-ray diffraction analysis mainly. About 0.8-1.0 of $Al_2O_3/C_3O$ mol ratio and less than 4 percent of $SiO_2$ were desirable for the effective formation of CA. The small amount of alkali and sulphur contents contained in refined alumina from alunite as the impurities were affected to form $C_4A_3S$ and $C_3S_2$, disadvantageous compounds for the alumina cement, therefore the impurities should be restricted in minimum content as possible.

• Transactions on Electrical and Electronic Materials
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• 제16권5호
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• pp.227-233
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• 2015

To reduce the cost of solar electricity, the crystalline-silicon (c-Si) photovoltaic industry is moving toward the use of thinner wafers (100 μm to 200 μm) to achieve a high efficiency. In this field, it is imperative to achieve an effective passivation method to reduce the electronic losses at the c-Si interface. In this article, we review the most promising surface passivation schemes that are available for high-efficiency solar cells.

• 한국작물학회지
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• 제31권2호
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• pp.238-241
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• 1986

규산 시용에 의한 하고기 오챠드그라스의 고온장해 경감 효과를 구명하기 위하여 온냉조절 온실에서 식양질토로서 Pot 재배하여 정상 관리한 상태하에서 오챠드그라스의 생육, 규산흡수능력 및 엽신중 에틸렌 생성량을 분석한 후 재배환경(온도, 토양수분등)이 불량한 야산지 토양에서 실증시험하여 하고기의 수양성과 식료영양가를 검토한 결과 ; 1. Pot 재배에서는 규산 시용량 증가로 오챠드그라스의 초장이 길어졌고 직립화 되었으며 생률중 및 건초중이 증가되었다. 또한 엽신중 규산함량은 증가된 반면 에틸렌 생성은 줄어들어 엽신고사율도 낮아졌다. 2. 야산지 토양에서도 규산 시용으로 에틸렌생성이 현저히 줄었고 사료생산에 있어서도 사료가를 낮추지 않으면서 하고기 이전에는 11 %, 하고기에는 9 %의 증수를 가져와 하고경감(고온장해) 효과가 인정되었다.

• 천문학회보
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• 제40권1호
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• pp.59.2-59.2
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• 2015

We present the results of simultaneous observations of the H2O and SiO masers emitted from the circumstellar envelopes of the late-type stars. These observations have been carried out at the K and Q bands using KVN since 2014 August and were scheduled to test the feasibility of multi-frequency phase referencing analysis on the maser lines. In order to increase the accuracy of group delay solution in the fringe search on the continuum source, the IF channels were randomly distributed within the available bandwidth of 500 MHz in each band. The positions of all maser spots are relatively described with respect to the position of the reference continuum source through the source frequency phase referencing technique, and this provides the astrometric position accuracy. Therefore, the relative locations of the H2O maser spots with respect to the SiO maser spots are determined from our observations, and the capability of the simultaneous multi-band observation of KVN is proved to be powerful to study the maser pumping mechanism around the late-type stars.

• 한국토양비료학회지
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• 제19권1호
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• pp.32-37
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• 1986

벼에 대(對)한 규회석(硅灰石) 및 광재규산질비료(鑛滓珪酸質肥料)의 시용효과(施用效果)를 검토(檢討)하기 위(爲)해 유효규산함량(有效珪酸含量)이 56ppm정도(程度)인 사양토(砂壤土)에서 3년간(年間) 포장시험(圃場試驗)을 실시(實施)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 규회석(硅灰石) 및 광재규산질비료시용(鑛滓硅酸質肥料施用)은 생육초기(生育初期)에는 분얼(分蘖) 및 초장(草長)을 억제(抑制)하나 생육후기(生育後期)에는 분얼수(分蘖數)를 늘리고 초장(草長)을 길게 했었다. 2. 규회석(硅灰石) 및 광재규산질비료시용(鑛滓硅酸質肥料施用)으로 수량(收量)은 증대(增大)되었으며 규회석(硅灰石) 및 광재규산질비료(鑛滓硅酸質肥料施)를 동일량(同一量)으로 시용(施用)했을 때의 수량증대효과(收量增大效果)는 같았다. 3. 수확기(收穫期) 식물체(植物體)의 규산흡수이용율(珪酸吸收利用率)은 광재규산질비료(鑛滓硅酸質肥料) 시용(施用)보다 규회석시용(硅灰石施用)에서 더 높았다. 4. 시험후(試驗後) 토양중(土壤中) 유효규산잔존율(有效珪酸殘存率)은 규회석시용(硅灰石施用)보다 광재규산질비료(鑛滓硅酸質肥料施) 시용(施用)에서 높았다. 5. 시험후(試驗後) 토양중(土壤中)의 유효규산함량증가(有效珪酸含量增加)는 규회석(硅灰石) 및 광재규산질비료(鑛滓硅酸質肥料施)에 관계(關係)없이 0.5N-HCl 가용규산성분함량(可溶珪酸成分含量)으로 1kg/10a 시용시(施用時) 약(約) 2.3ppm 증가(增加)되었다. 6. 식물체(植物體)의 $SiO_2/N$비(比)가 클수록 목도열병(稻熱病) 이병율(罹病率)은 감소(減少)하는 경향(傾向)이었다.

• 한국세라믹학회지
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• 제26권5호
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• pp.625-630
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• 1989

Aluminium silicate gels were prepared by gel-technique using Al(OH)3 and TEOS as starting materials. Aluminium silicate gel as formed mullite at 120$0^{\circ}C$. From this method, homogeneous mullite was formed available needle-like shaped and close compacted. As excess SiO2 mullite composition, the needle-like shaped crystal, size according to increased with SiO2, was increased from 3${\mu}{\textrm}{m}$ to 7${\mu}{\textrm}{m}$ but liquid phase did not affect the formation of needle-like shaped mullite. As excess Al2O3 mullite composition, the needle-shape mullite crystal could not be detected because Al2O3 acted as chunky behavior.

• 보존과학회지
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• 제38권4호
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• pp.289-300
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• 2022

In the 6^th and 7^th centuries, 5 iron artifacts excavated form the Baekje Stone Tomb in Guryong-ri site, Ungcheon, Boryeong, were studied. The sample were metal microscopic observation, SEM-EDS analysis and Raman micro-spectroscopy analysis were conducted to understand the metallurgical characteristics. The microstructure observation showed the presence of ferrite and pearlite throughout, and differences in carbon content existed depending on the direction. Non-metallic inclusions were in the form of long lines, and most of them were wüstite, fayalite. It is indicated that the artifacts were forge welded using hypoeutectoid steel, with signs of carburizing and decarburizing processes. Some crystals with high P₂O₅, TiO₂, CaO content were identified as sarcopside, ulvöspinel, and perovskite, respectively, through Raman spectroscopy. A comparison of the results with previous studies on the sites of Bujang-ri site in Seosan and Bongseon-ri site in Seocheon, which are adjacent sites in the coastal area, revealed that, while heat treatment technology was available, the artifacts were not heat-treated considering the purpose for use for these artifacts. The chemical composition of the non-metallic inclusions P₂O₅, TiO₂, CaO were plotted in proportions to SiO₂ and compared with adjacent sites. Considering that the P₂O₅/SiO₂ ratio was widely distributed, the refining technology was not uniform. In addition, the TiO₂/SiO₂ ratio was found to be higher than that of other sites, meaning that a titanium-containing ore was used to manufacture the artifacts, unlike in surrounding sites, but it is not detected in all artifacts, so it may have been affected by various factors such as furnace walls in addition to raw materials. Although slag formers were used, considering the CaO/SiO₂ ratio and the (Al₂O₃/SiO₂)/(CaO/SiO₂) ratio, which appear to be similar to the surrounding sites, but it is possible that CaO containing raw ore was used because it is also affected by the components of raw ore. As a result of the study, it is highly likely that ore different from that of the surrounding sites was used for production, but a more comprehensive comparative study with the surrounding sites is needed in the future.