• 박물관보존과학
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• 제1권
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• pp.15-26
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• 1999

국립김해박물관의 개관을 위해 전시유물 200여점을 보존처리 하였다. 처리유물은 대부분 고분출토품이며 재질은 금동, 은, 구리합금제, 철제 등 금속유물이 주종을 이루고 있다. 모두 고대 가야문화를 대표하는 문화재들이다. 유물은 상태에 따라 처리방법을 달리했다. 구리합금제 유물은 부식물의 안정성에 따라 보존과 제거를 결정했다 특히 철제품의 경우 현재 안정한 상태의 유물은 물리적인 방법으로 이물질을 제거해 원형을 찾고 방녹제[상품명:Ballistol]를 이용해 부식을 예방하는데 중점을 두었다. 부식이 진행중인 유물은 원인제거를 위해 2단계 탈염처리를 했다. 제 1단계는 0.3M NaOH 용액함침, 제 2단계는 붕사-증류수 가압탈염법이다. 이밖에 전시를 위한 특수 받침대제작 및 각종 전시보조물인 모형 등에 대한 수정작업도 지원했다.

• 식물병연구
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• 제18권3호
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• pp.194-200
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• 2012

국내 밀의 붉은곰팡이병의 효과적인 방제 약제 선발을 위하여 배지와 포장에서 Fludioxonil 등 14종의 약제에 대해 균의 생육 억제와 병 발생 감소 효과를 조사하였다. 배지상의 균사 억제 정도는 Fludioxonil 종자처리액상수화제와 액상수화제, Benomyl + Thiram 수화제가 효과적인 것으로 나타났다. 약효 성분 특성면에서는 Cyanopyrrole계(Fludioxonil)와 Dithiocarbamate계(Thiram)가 효과적이었다. 반면, 무기유기 동제(Copper hydroxide, Oxine-copper)와 Cabarmate계(Thiophanate-methyl) 등은 균의 생육 억제효과가 없는 것으로 나타났다. 포장에서의 병 방제 효과 검정을 위해 Fludioxonil 액상수화제, Captan 수화제, Difenoconazole + propiconazole 유제와 Metconazole 액상수화제 등 4종을 시험하였다. 전북 김제와 익산 두 지역의 포장에서 4월 30일과 10일 후인 5월 10일 2회 약제처리 후 밀의 붉은곰팡이병 방제 효과를 검정 하였다. 병 발생 정도는 지역간에 약간 차이를 보여 김제와 익산에서 각각 무처리에서 45.0%와 33.7%의 감염수율을 보였다. 약제별 발병률은 김제에서는 0.3-2.2%로 전체 약제에서 95% 이상의 방제가를 보였다. 익산의 경우는 김제에 비해 약제 처리구에서 약간 더 높은 발병수율을 보였으나, 방제가는 약제간에 87-90%로 좋은 효과를 보였다. 약제 처리에 의한 특이적인 약해 증상은 나타나지 않았다. 본 시험 결과로 4 종의 약제 모두 밀 붉은곰팡이병 방제에 효과적인 것으로 나타났다.

• The Plant Pathology Journal
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• 제17권5호
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• pp.249-256
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• 2001

Xanthomonas axonopodis pv. glycines 8ra produces a bacteriocin called glycinecinA, which specifically inhibits the growth of bacteria belonging to Xanthomonas species. GlycinecinA was produced by culturing Escherichia coli DH5 containing biosynthetic genes for glycinecinA, and was tested for its control effect against X. vesicatoria on red pepper and X. oryzae pv. oryzae on rice. The bacteriocin activity was much higher in the cell extract than in the supernatant. It reached a maximum level at the stationary phase, ws maintained up to 2 months at room temperature and approximately 10 months at $4^{\circ}$. The optimum concentration of glycinecinA for the control in the greenhouse and in the field was 12,800 AU/ml. In this study, the activity of glycinecinA on rice and red pepper leaves continued for 7-8 days, during which the pathogen populations remained at low levels. Bacterial leaf spot of red pepper and bacterial leaf blight of rice were significantly reduced by the bacteriocin treatments. The control efficacy was as high as, or even higher than, the chemical treatment of copper hydroxide. These results suggest that the bacteriocin is a potential control agent for bacterial diseases.

• Journal of Microbiology and Biotechnology
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• 제19권5호
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• pp.520-524
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• 2009

Two isolates, Bacillus sp. BS87 and RK1, selected from soil in strawberry fields in Korea, showed high levels of antagonism towards Fusarium oxysporum f. sp. fragariae in vitro. The isolates were identified as B. velezensis based on the homology of their gyrA sequences to reference strains. BS87 and RK1 were evaluated for control of Fusarium wilt in strawberries in pot trials and field trials conducted in Nonsan, Korea. In the pot trials, the optimum applied concentration of BS87 and RK1 for pre-plant root-dip application to control Fusarium wilt was $10^5$ and $10^6$ colony-forming units (CFU)/ml, respectively. Meanwhile, in the 2003 and 2005 field trials, the biological control efficacies of formulations of RK1 were similar to that of a conventional fungicide (copper hydroxide) when compared with a non-treated control. The RK1 formulation was also more effective than BS87 in suppressing Fusarium wilt under field conditions. Therefore, the results indicated that formulations of B. velezensis BS87 and RK1 may have potential to control Fusarium wilt in strawberries.

• Advances in nano research
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• 제3권3호
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• pp.169-176
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• 2015

Iron nanoparticles were made by using the modified coprecipitation technique. Usually the characteristics of synthesised particles depend upon the process parameters such as the ratio of the iron ions, the pH of the solution, the molar concentration of base used, type of reactants and temperature. A modified coprecipitation method was adopted in this study. A magnetic stirrer was used for mixing and the morphology and nature of particles were observed after synthesis. Nanoparticles were characterised through XRD. Obtained nanoparticles showed the formation of magnetite and maghemite under citric acid and oxalic acid as stabilisers respectively. The size of nanoparticle was greatly affected by the use of different types of stabilisers. Results show that citric acid greatly reduced the obtained particle size. Particle size as small as 13 nm was obtained in this study. The effects of different kinds of nucleating agents were also observed and two different types of nucleating agents were used i.e. potassium hydroxide (KOH) and copper chloride ($CuCl_2$). Results show that the use of nucleating agent in general pushes the growth phase of nanoparticles towards the end of coprecipitation reaction. The particles obtained after addition of nucleating agent were greater in size than particles obtained by not utilising any nucleating agent. These particles have found widespread use in medical sciences, energy conservation and electronic sensing technology.

• 한국표면공학회지
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• 제43권1호
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• pp.1-6
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• 2010

The effect of organic additives, 1-(3-sulfoproyl)-2-vinylpyridineium hydroxide (SVH) and thiourea (TU), on the precision copper electrodeposition was investigated with optical, electrochemical and x-ray diffraction techniques. It was found that SVH played a r ole as a n accelerator and TU as an i nhibitor during the electroreduction of cupric ions in acidic Cu electroplating solution. Through electrochemical measurements, TU showed more strong interaction with cupric ions than SVH and dominated overall Cu electroplating process when both additives were present in the solution. In the case of three dimensional Cu electrodeposition on the 20 ${\mu}m$-patterned Ni substrates, SVH controlled the upright growth of Cu electrodeposits and so determined its flatness, while TU prohibited the lateral spreading of Cu in the course of pulse-reverse pulse current adaptation. With microscopic observation, we obtained the optimum organic additives composition, that is, 100 ppm SVH and 200 ppm TU during the current pulsation.

• 한국토양비료학회지
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• 제43권6호
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• pp.872-879
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• 2010

LCHs는 높은 구리함량 뿐만 아니라 고결정도, 음이온교환능력 및 규칙적인 층상 구조 등을 가지고 있어 살균제로 활용가능성이 높다. 본 연구에서는 최초로 고농에서 LCHs를 합성하였으며, 다양한 반응인자에 따른 결정학적 및 물리적 특성을 규명하여 최적조건을 설정하였다. $Cu(NO_3)_2$ 용액에 NaOH 용액을 첨가하여 합성된 LCHs의 결정성은 후숙시간에 따라 약간 증가하였으나, 0.5시간 이후에는 거의 변화가 없었다. 반응온도에 따른 LCHs의 XRD 피크의 강도 및 패턴은 매우 유사하였으나, LCHs 현탁액의 안정성은 반응온도가 증가할수록 감소하는 경향을 나타내었다. LCHs의 결정성은 반응용액의 pH가 높아질수록 증가하였으나, pH 9.0 이상에서는 오히려 감소하는 경향을 나타내었다. 또한, 반응용액의 pH에 따라 LCHs 현탁액의 색상과 안정성이 다양하게 변화되었다. $Cu(NO_3)_2$ 농도가 증가할수록 반응용액의 점성이 증가되었으며, LCHs의 결정성은 상대적으로 낮아졌다. NaOH 용액 5.0 M에서 합성된 LCHs의 결정성은 뚜렷하게 감소하였으나, 현탁액의 안정성은 NaOH 농도가 높아질수록 증가하였다. 그러므로 LCHs의 최적 합성조건은 후숙 2시간, 반응온도 $25^{\circ}C$, 반응용액의 pH 6.0, $Cu(NO_3)_2$ 및 NaOH 용액의 농도는 3.0 M 이었다. 최적 반응조건에서 합성된 LCHs는 골격구조를 형성하는 OH, 층간의 $H_2O$ 및 $NO_3$로부터 기인하는 흡수 band가 FT-IR 분석에서 뚜렷하게 나타났다. LCHs의 탈수 및 결정구조의 파괴는 $206{\sim}246^{\circ}C$의 매우 좁은 온도범위에서 발생하였으며, 무게감량이 31.8%로서 이론적인 값인 33.6%와 비슷하게 나타났다. $25^{\circ}C$에서 합성된 LCHs는 0.2~0.8 ${\mu}m$ 크기의 plate 형태를 나타내었으나, 반응온도 및 반응용액의 pH가 증가할수록 입자 크기가 증가할 뿐만 아니라 그들의 입자모양도 변화되었다. 무기 구리제의 병원균에 대한 작용기작은 식물체 표면에 처리된 구리제가 건조 후 엷은 막을 형성하고, 공기 중의 이산화탄소나 탄산을 함유한 빗물, 이슬, 식물체 또는 미생물의 분비물에 의해 가용성의 구리염으로 변화되어 방출된 구리이온이 병원균과 접촉하여 효과를 발현한다. 따라서 작물보호제 처리 시 식물체 표면 흡착이 증가할수록 방제효율은 증가되며, 일반적으로 입자의 크기가 작을수록 식물표면 흡착은 증가한다. 그러므로 본 연구에서 합성된 HDCS는 합성공정이 간단하며, 고농도에서도 합성이 가능할 뿐만 아니라 입자크기가 작고 현탁액의 안정성이 높기 때문에 구리 살균제로서의 활용가능성이 높은 것으로 판단되었다.

• 한국광물학회지
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• 제23권4호
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• pp.305-313
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• 2010

콩고민주공화국의 중앙아프리카 구리광화대에서 수입하는 Cu-Co 광석의 광물학적 특성을 X-선 회절 분석, 2차원 X-선 회절 분석과 전자현미분석에 의하여 연구하였다. 검은색 광석은 코발트 광석광물인 헤테로제나이트와 구리 광석광물인 공작석, 초록색 광석은 공작석으로 주로 구성된다. 헤테로제나이트는 반사 현미경 하에서 매우 밝은 흰색을 나타내며 X-선 회절 분석에서는 $4.39{\AA}$과 $2.316{\AA}$ 피크를 가지는 3R 다형으로 확인된다. 그러나 전형적인 3R형에 비하여 낮은 NiO와 $Fe_20_3$의 함량으로 미루어 보아, 3R 다형 이외에 2H 다형도 일부 존재하는 것으로 판단된다. 공작석은 반사 현미경하에서 밝은 회색을 나타내며, 화학식은 $Cu_{1.97}Co_{0.02}Fe^{2+}{_{0.01}}CO_3(OH)_2$이다. 헤테로제나이트와 공작석은 중앙아프리카 구리광화대의 광화작용 중 최후기인 표성부화기에 형성되었으며, 코발트는 일차 광석보다는 표성작용에 의하여 형성된 (산)수산화 광석에 더 많이 부화되었을 것으로 추정된다.

• Restorative Dentistry and Endodontics
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• 제39권2호
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• pp.89-94
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• 2014

Objectives: The aim of this study was to evaluate the cytotoxicity, setting time and compressive strength of MTA and two novel tricalcium silicate-based endodontic materials, Bioaggregate (BA) and Biodentine (BD). Materials and Methods: Cytotoxicity was evaluated by using a 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-((phenylamino)carbonyl)-2H-tetrazolium hydroxide (XTT) assay. Measurements of 9 heavy metals (arsenic, cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc) were performed by inductively coupled plasma-mass spectrometry (ICP-MS) of leachates obtained by soaking the materials in distilled water. Setting time and compressive strength tests were performed following ISO requirements. Results: BA had comparable cell viability to MTA, whereas the cell viability of BD was significantly lower than that of MTA. The ICP-MS analysis revealed that BD released significantly higher amount of 5 heavy metals (arsenic, copper, iron, manganese, and zinc) than MTA and BA. The setting time of BD was significantly shorter than that of MTA and BA, and the compressive strength of BA was significantly lower than that of MTA and BD. Conclusions: BA and BD were biocompatible, and they did not show any cytotoxic effects on human periodontal ligament fibroblasts. BA showed comparable cytotoxicity to MTA but inferior physical properties. BD had somewhat higher cytotoxicity but superior physical properties than MTA.

• 한국환경농학회지
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• 제19권5호
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• pp.401-418
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• 2000

1. Production of the artificial zeolite from coal ash Coal fly ash is mainly composed of several oxides including $SiO_2$ and $Al_2O_3$ derived from inorganic compounds remained after burning. As minor components, $Fe_2O_3$ and oxides of Mg, Ca, P, Ti (trace) are also contained in the ash. These components are presented as glass form resulting from fusion in the process of the combustion of coal. In other word, coal ash may refer to a kind of aluminosilicate glass that is known to easily change to zeolite-like materials by hydrothermal reaction. Lots of hot seawater is disposing near thermal power plants after cooling turbine generator periodically. Using seawater in the hydrothermal reaction caused to produce low price artificial zeolite by reduction of sodium hydroxide consumption, heating energy and water cost. As coal ash were reacted hydrothermally, peaks of quartz and mullite in the ash were weakened and disappeared, and new Na-Pl peaks were appeared strengthily. Si-O-Si bonding of the bituminous coal ash was changed to Si-O-Al (and $Fe^{3+}$) bonding by the reaction. Therefore the produced Na-Pl type zeolite had high CEC of 276.7 $cmol^+{\cdot}kg^{-1}$ and well developed molecular sieve structure with low concentration of heavy metals. 2. Utilization of the artificial zeolite in agro-environment The artificial zeolite(1g) could remove 123.5 mg of zinc, 164.7 mg copper, 184.4 mg cadmium and 350.6 mg lead in the synthetic wastewater. The removability is higher 2.8 times in zinc, 3.3 times in copper, 4.7 times in cadmium and 4.8 times in lead than natural zeolite and charcoal powder. When the heavy metals were treated at the ratio of 150 $kg{\cdot}ha^{-1}$ to the rice plant, various growth inhibition were observed; brownish discoloration and death of leaf sheath, growth inhibition in culm length, number of panicles and grains, grain ripening and rice yield. But these growth inhibition was greatly alleviated by the application of artificial zeolite, therefore, rice yield increased $1.1{\sim}3.2$ times according to the metal kind. In addition, the concentration of heavy metals in the brown rice also lowered by $27{\sim}75%$. Artificial Granular Zeolites (AGZ) was developed for the purification of wastewater. Canon exchange capacity was 126.8 $cmol^+{\cdot}kg^{-1}$. AGZ had Na-Pl peaks mainly with some minor $C_3S$ peaks in X-ray diffractogram. In addition, AGZs had various pore structure that may be adhere the suspended solid and offer microbiological niche to decompose organic pollutants. AGZ could remove ammonium, orthophosphate and heavy metals simultaneously. Mixing ratio of artificial zeolite in AGZs was related positively with removal efficiency of $NH_4\;^+$ and negatively with that of $PO_4\;^{3-}$. Root growth of rice seedling was inhibited severely in the mine wastewater because of strong acidity and high concentration of heavy metals. As AGZ(1 kg) stayed in the wastewater(100L) for 4days, water quality turned into safely for agricultural usage and rice seedlings grew normally.