• 농업과학연구
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• 제44권2호
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• pp.211-220
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• 2017

We conducted this study to determine the recommended application rate of fertilizer for Houttuynia cordata Thunb cultivation. The effects of various application levels of N, $P_2O_5$, and $K_2O$ fertilizers on the growth of this plant were investigated and the associated changes in soil properties were evaluated in the field. Soil pH at harvest time of Houttuynia cordata Thunb did not differ from that before fertilization, whereas EC tended to decrease during cultivation. The soil organic matter (SOM) and available phosphorus increased after treatment, and the amount of applied fertilizer ($P_2O_5$) and available phosphorus were proportional. The nitrogen absorption amount increased in N 100% treatment, but decreased in N 150% treatment. The phosphorus absorption amount rose with the fertilizer treatment concentration until $P_2O_5$ 150% treatment. The amount of absorbed potassium decreased in treatments with $K_2O$ 150% and $K_2O$ 200%. The plant length was the longest in N 100%, $P_2O_5$ 150%, and $K_2O$ 200%. The stem diameter was estimated to be 3.46 - 3.67 mm in N 100 - 200% treatment, 3.55 - 3.67 mm in $P_2O_5$ 100 - 150%, and 3.79 mm in $K_2O$ 200%. The number of tillers did not differ amongst fertilization treatments. The fresh weight was summed to be 3.67 ton/10 a in N 100% treatment, 3.79 Mg/10 a in $P_2O_5$ 150%, and 3.83 Mg/10 a in $K_2O$ 150%. Thus, the relationship between the fertilizer amount and yields of the plant showed that the most economical quantity of fertilizers should be 10.2 N kg/10 a, 5.5 $P_2O_5$ kg/10 a, and 8.2 $K_2O$ kg/10 a for Houttuynia Cordata Thunb.

• 공업화학
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• 제18권4호
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• pp.356-360
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• 2007

나노 다공질 $TiO_2$ 전극막, 광 감응형 염료, 전해질 그리고 상대전극으로 구성된 염료감응형 태양전지(Dye-Sensitized Solar Cells, DSSCs)는 최근에 많은 관심을 받아오고 있다. 염료감응형 태양전지에서 $TiO_2$ 전극막은 태양광의 흡수량을 증가시키기 위해 가능한 많은 양의 Ru 착물을 표면에 흡착시켜야 하는데 이를 위해 높은 비표면적과 나노 다공성 입자로 구성된 광전극이 요구된다. 또한 에너지 전환 효율을 증가시키기 위한 방법으로 $TiO_2$ 페이스트의 제작시 산을 첨가 후 열처리하는 방법이 보고되고 있다. 이 논문에서는 산이 첨가된 페이스트로 제조한 $TiO_2$ 광전극이 염료감응형 태양전지의 에너지 변환 효율에 미치는 영향을 체계적으로 이해하기 위해 FE-SEM, XPS, EXAFS 그리고 AFM 등을 이용하여 제조된 광전극의 물리적 화학적 특성을 조사하였다. 또한 광전류-전압 곡선으로부터 산처리된 페이스트를 이용하여 제조한 염료감응형 태양전지의 에너지 전환효율을 평가하였다. 산처리된 페이스는 염료감응형 태양전지의 에너지 전환효율에 크게 영향을 미침을 알 수 있었다.

• 대한화학회지
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• 제40권2호
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• pp.109-116
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• 1996

물시료 중 존재하는 흔적량 게르마늄을 전열 원자흡수 분광광도법으로 정랑하기 위해 사용되는 매트릭스 개선제의 종류와 사용량, 이에 따를 회화 및 원자화 온도의 변화, 보조제의 사용여부 및 양에 관하여 연구하였다. 게르마늄은 회화단계에서 이산화 게르마늄이 흑연로 성분인 탄소로 인해 휘발성 일산화 게르마늄으로 환원되에 감도 및 재현성을 저하시킨다. 따라서 개선제를 사용하여 게르마늄을 열적 및 화학적으로 안정화시켜야 한다. 이를 위해 단일 개선제를 사용할 경우 파라듐이 가장 좋은 효과를 나타내었다. 이 경우 원자화온도는 변화시키지 않지만, 회화온도는 800.deg.C에서 1, 000.deg.C로 올릴수 있었고 흡광도도 증가하였다. 이런 조건에서 팔라듐의 농도가 게르마늄에 대해 몰비로 14-100인 10-70.mu.g/mL까지 흡광도가 일정하였다. 보조개선제의 사용도 검토하였는데, 1% 수산화암모늄을 가하여 회화온도를 1, 000.deg.C까지 증가시켰다. 이제까지 검토한 최적조건을 바탕으로 광천수 3가지를 분석한 결과 게르마늄이 2.46, 1.60 및 0.020.mu./mL이었다. 끝으로, 시료에 일정량의 게르마늄을 첨가하여 얻은 회수율은 모두 95%이상으로 정량적이라고 할 수 있고, 검출한계는 6.9ng/mL로 흔적량 게르마늄 분석에 유용한 것으로 판단되었다.

• Archives of Plastic Surgery
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• 제36권5호
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• pp.531-537
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• 2009

Purpose: Alveolar bone grafting has become an essential process in the treatmemt of alveolar cleft patient for stabilization of the maxillary arch, elimination of oronasal fistula, the reconstruction of the soft tissue nasal base support, and creation of bony support for tooth eruption for implant. The use of Autologous iliac cancellous bone is preferable because of the adequate quantity and high osteoinductive potential. However, even with iliac bone, insufficient osteoregeneration and absorption occur due to several factors such as the patient's age, cleft width, functional stress, and others. In order to increase osteoregeneration where the iliac bone is placed, the present study is associated with bone marrow aspirate (BMA). The experimental study evaluated the efficacy of osteoregeneration in normal cleft rabbits when alveolar bone grafting was performed with autologous iliac corticocancellous bone. Methods: Twenty - four New Zealand White rabbits were divided randomly into 2 groups (BMA, control). All animals underwent harvesting of corticocancellous bone graft from the right posterior iliac crest via standard surgical technique. $1m{\ell}$ of BMA were obtained by scraping the needle and aspirate with $10m{\ell}$ syringe from the contralateral iliac bone wall. The muco - periosteal flap on the palate was elevated. A mixture of Equal bone's volumes with BMA and saline as its control was inserted into the cleft. Animals were sacrificed at 2, 4, and 8 weeks and maxilla was harvested for dental peri - apical X-ray, bone matrix density (BMD),and histologic analysis. Result: BMD of regenerated bone to the cleft in the rabbits was higher than that of the control rabbits. X-ray, histologic analysis showed that increased osteoregeneration and low absorption rate were observed in the BMA group. Conclusion: Our experimental study showed BMA enhanced the osteoregeneration and survival rate of alveolar bone grafting. BMA is easy to extract & cost - time effective. So it can be an effective enhancers for bone grafting mixtures.

• 한국세라믹학회지
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• 제45권8호
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• pp.459-463
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• 2008

$P_2O_5-SnO_2$ system $0.5SnO_2-xP_2O_5-(0.5-x)B_2O_3$(x=0.1, 0.2, 0.3, 0.4, 0.5) glasses have been prepared for Pb-free low temperature glass frit. A investigation about the effect of $B_2O_3$ substitution on properties of $P_2O_5$ glasses, including glass structure properties, thermal properties, and mechanical properties was presented. Substance that is responsible for in moisture absorption existing circumstances supposes by phosphate, and excess moisture tolerance that state funeral's structure is improved breaking does not affect in state funeral bond that only most single bond remains, and can know that does not suffer big impact in boric oxide anomaly present state. This phenomenon estimates that connect with structure change. It is thought according to link this result the phosphoric acid happened structural change. $B_2O_3$ displacement quantity 0.3 mole put out $BO_4$ structures, but above 0.3 mole it changed with the case $BO_3$ structure which it displaces.

• 대한치과보철학회지
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• 제33권2호
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• pp.317-334
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• 1995

The purpose of this study was to compare the bone formation, maturation around HA-and titaniumcoated dental implants in dog. 5 hydroxyapatite coated IMZ implants and 5 titanium coated IMZ implants were placed into the previously extracted site in the mandible of 5 adults dogs. All dogs were injected intravenously Tetracycline, Alizalin red S, and Calcein for bone fluorescent labelling, After the experimental period of 16weeks, the dogs were sacrificed and tissue samples around the implants were obtained. Microscopic observations(ligth, polariged and fluorescence microscope), morphometric analysis, line profile with EPMA, and quantitative analysis for Ca,P, and Ti were performed. The results were as follows ; 1. Bone maturations around the implants were relatively lower than those of natural teeth. No significant differences in bone maturation and remodeling patterns were observed between the two implants groups. 2. Calcification of bone surrounding the implants was initiated in 8-11 weeks for HA-coated implants, while it took 11 weeks or more for Ti-coated implants. 3. Bone-to-implants contact ratio of 82.63% was recorded for HA-coated group and 72.25% for titanium coated group, with no significant difference between the two groups. 4. Bone around the implants exhibited reduced quantity of Ca and P in the $100{\mu}m$ region relative to natural teeth, while the rest of the regions showed no statistical differences. No significant differences were found between the two implant groups. 5. There was a separation of HA layer from the implant core and subsequent infiltration of inflammatory cells into the resulting space in the HA-coated implants, and evidences of phagocytosis of HA particles by macrophages. Bone calcification was more rapid around HA-coated implants compared to titanium-coated implants, but HA coated implants did not show any significant differences either in the degree of calcification or the bone-to-implant contact ratio over Ti coated implants. HA coated implants may have complications associated with HA absorption and separation of HA layer from the implant core.

• 한국진공학회지
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• 제10권1호
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• pp.104-111
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• 2001

$SiH_4$, $CH_4$, $B_2H_6$ 혼합기체를 이용하여 플라즈마 화학증착법으로 비정질 탄화실리콘(a-SiC:H) 박막을 증착하였다. 기상 doping 농도를 0에서 $2.5\times10^{-2}$ 범위에서 변화시켜 얻은 박막의 물성을 SEM, XRD, Raman 분광법, FTIR, SIMS, 광흡수도와 전기전도도 분석을 통하여 살펴보았다. $B_2H_6$/($CH_4+SiH_4$) 기체유량비가 증가할수록 붕소의 도핑효율와 미세결정성은 감소하였다. 증착 중 $B_2H_6$ 기체가 첨가됨에 따라 비정질 탄화실리콘 박막의 Si-C-H 결합기의 강도는 감소하였으며, 이의 영향으로 박막내의 수소함량은 $B_2H_6/(SiH_4+CH_4$) 기체 유량비가 증가함에 따라 16.5%에서 7.5%로 단조감소하였다. $B_2H_6(CH_4+SiH_4$) 기체유량비가 증가할수록 a-SiC:H 박막의 광학적 밴드갭과 전기활성화 에너지는 감소하였고, 전기전도도는 증가하였다.

• 공업화학
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• 제16권3호
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• pp.317-322
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• 2005

오늘날 대규모 건설사업에 따른 골재의 고갈과 환경보호 측면에서 폐콘크리트 골재의 재활용이 절실히 요구되고 있다. 본 연구에서는 페콘크리트의 분쇄공정에서 발생되는 페콘크리트 미분말을 폴리머 모르타르의 충전재 대용으로 재활용하고자 하였다. 폴리머 모르타르의 공시체는 폴리머 결합재의 첨가율을 9~15 wt%, 실리카 미분말 충전재 대용의 폐콘크리트 미분말 치환율을 0~20 wt%, 0.1~0.3 mm 잔골재(21~24 wt%)와 0.7~1.2 mm 잔골재(44~47 wt%)의 첨가율을 65~71 wt% 범위로 다양하게 변화시켜 제조하였다. 폴리머 모르타르의 물성을 평가하기 위하여 압축 및 휨강도, 흡수율, 내열수성, 내산성, 세공분포특성, 전자현미경에 의한 미세조직 관찰시험을 행하였다. 시험결과, 폴리머 모르타르의 물성은 폴리머 결합재의 첨가율 증가에 따라 현저히 증가되었으나 페콘크리트 미분말의 치환율 증가에 따라서는 크게 저하되었다.

• 한국수산과학회지
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• 제41권6호
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• pp.458-465
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• 2008

The nutritional contribution of mideodeok extracts (ME) on rockfish (Sebastes schlegelii) feed and fish muscle was investigated. Different concentrations of the ME mixed with commercial diet were fed to mature rockfish for 8 weeks. The lipid and ash contents of the formulated diets were relatively similar to the control diet, while increasing the extract concentration increased the moisture content and decreased the protein contents. Major fatty acid components (C18:1n-9, 16:0, C20:5n-3, C22:6n-3) were of comparable quantity. High presence of C18:2n-6 was attributed to soybean oil incorporated in the diets, while the essential fatty acids were within limits (0.9-1.0%). The diet fortified with 6% ME produced the highest feed efficiency, with increased protein content in the muscle as well as lipid content for both muscle and liver. Hepato- and visceral-somatic index values were elevated with increasing ME concentration Muscle fatty acid contents were mostly C18:1n-9 and C16:0, with low absorption of C18:2n-6 in both the muscle and liver. Total highly unsaturated fatty acid content was significantly reduced in the fish muscle, but the values were higher for fish fed with a ME-fortified diet. An increasing trend for eicosapentaenoic acid and docosahexaenoic acid was also observed with increased ME fortification, with liver levels of these compounds remaining within range throughout the duration of the experiment.

• 한국전자파학회논문지
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• 제26권5호
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• pp.506-513
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• 2015

본 논문에서는 메타물질 흡수체를 사용한 새로운 에탄올 농도 검출 센서를 제안한다. 메타물질 흡수체는 분할고리십 자공진기(SRCR: Split Ring Cross Resonator) 구조와 미세유체 채널로 구성되어 있다. SRCR 구조는 capacitive 간극 부근의 실효 유전율에 민감하게 반응하는 LC 공진을 발생시킨다. 미세유체 채널은 마이크로 리터 단위의 극미량 액체를 사용하여 유전체 기판의 실효 유전율을 변화시킬 수 있다. 본 연구에서 제안한 미세유체 메타물질 흡수체는 미세유체 채널에 주입된 에탄올의 농도에 따른 전기적 특성을 감지하여 그 농도를 검출할 수 있다. 제안된 흡수체는 도파관 측정법을 사용하여 측정하였고, 미세유체 채널에 각기 다른 농도의 에탄올이 흐를 때 공진 주파수가 이동하는 것을 확인하였다. 또한, 시뮬레이션과 측정 결과 사이에 높은 일치율을 보인다.