• 자원리싸이클링
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• 제31권3호
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• pp.73-80
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• 2022

폐리튬이온전지를 고온에서 용융환원하면 금속혼합물을 얻을 수 있다. 금속혼합물을 황산이나 염산으로 침출한 다음 용매추출로 분리한 여액에는 니켈(II), 코발트(II), 망간(II)과 실리케이트(IV)가 함유되어 있다. 본 논문에서는 양이온교환수지인 Diphonix와 P204를 사용하여 황산과 염산 합성용액에 함유된 상기 이온들의 이온교환거동을 조사했다. 용액의 pH가 3인 황산용액에서 니켈(II), 코발트(II)와 망간(II)이 선택적으로 Diphonix에 흡착되었다. 용액의 pH가 6인 염산용액에서는 망간(II)이 P204수지에 선택적으로 흡착되어 분리가 가능했다. Diphonix와 P204에 흡착된 금속이온은 황산이나 염산용액으로 세출할 수 있었다.

• 한국약용작물학회지
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• 제12권3호
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• pp.243-248
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• 2004

인간 면역 세포 중 하나인 T세포에 대한 각 시료의 생육촉진 활성은 시료의 1.0 g/l에서 기준물질로 사용한 유향열매의 정유 성분이 T세포의 생육촉진 활성 측정에서 가장 좋은 활성을 나타내었으며, 노간주나무의 열매의 정유성분이 줄기 부분의 정유 성분보다 높은 생육 촉진 활성을 보였다. T 세포의 각 cell 당 $TNF-{\alpha}$의 분비량을 살펴보면 모든 시료의 정유 성분들이 배양 2일째 최대분비량을 나타내었고, IL-6의 경우는 모든 시료들이 배양 시간 의존적으로 증가하는 경향을 나타내었다. 유방암 세포인 MCF-7에 대한 각 시료의 생육 억제 활성은 각 정유 성분에 대하여 농도 의존적인 경향을 나타내었으며, 가장 좋은 활성을 나타낸 시료는 노간주나무 열매의 정유 성분으로 약 84%의 높은 생육 억제 활성을 나타내었으며, 유향 열매와 노간주나무 줄기의 정유 성분들도 약 80%에 가까운 높은 생육 억제 활성을 나타내었다. 간암 세포인 Hep3B에 대한 각 정유 성분들의 암세포 생육 억제 활성도 유방암 세포와 같이 각 정유 성분에 대하여 농도 의존적인 경향을 나타내었으며, 유향 열매의 정유 성분이 약 83%의 높은 생육 억제 활성을 나타내어 가장 좋은 활성을 나타내었다. 항암 및 면역기능의 역할에 대한 분자수준에서의 검증을 위해 HL-60 세포의 분화도를 살펴본 결과, 배양 시간 의존적으로 분화도가 증가하는 경향을 나타내었으며, 유향열매의 정유 성분이 Control 군에 비하여 1.38배의 증진활성을 나타내어 가장 높은 분화도를 나타내었으며, 노간주 열매의 정유 성분이 줄기의 정유 성분에 비하여 높은 분화도를 나타내었다.

• 대한소아치과학회지
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• 제37권3호
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• pp.381-386
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• 2010

수직적으로 치관-치근 파절된 전치부에서 파절은 치근을 따라 다양한 부위에서 일어나기 때문에 그 깊이에 따라 치료 방법이 결정된다. 파절선이 치관부에 근접한 경우 치은 판막을 형성하여 파절 부위를 노출시키거나 교정적 또는 외과적으로 치아를 정출시키는 방법 등을 고려해 볼 수 있지만, 파절선의 위치가 깊은 경우 그 예후는 불량하며 치근의 1/3 이상을 넘어선 경우에는 발치가 일반적이다. 그러나 성장기 아동에서 상악 중절치의 발치는 심미적 문제, 치조골 흡수, 발음 문제 등 여러 합병증을 초래하게 되므로 성장기 동안 치아를 보존하는 것을 최우선의 목표로 한다. 그러므로 수직 치관-치근 파절된 전치부 치아의 치료 시 발치 대신 복합레진으로 파절선을 수복한 후 재식하는 의도적 재식술을 대안으로 선택할 수 있다. 본 증례에서는 외상으로 인하여 상악 중절치의 치관-치근 파절이 치근 1/2 정도로 깊게 발생한 혼합치열기 환아에서 해당치아를 의도적으로 발치하고 복합레진으로 파절 부위를 수복한 후 재식하였다. 이후 2년 동안 관찰한 결과 특이한 임상적 증상 없이 유지되고 있으며 심미적으로도 만족할 만한 결과를 얻을 수 있었다. 이 방법은 술식에 민감하며 장기적 예후에 대한 보고는 부족하지만, 치아를 보존할 수 있는 새로운 방법이라는 점에서 가치가 있다고 사료된다.

• 한국응용과학기술학회지
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• 제36권4호
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• pp.1088-1095
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• 2019

CKD 추출액은 시멘트공정에서 발생한 폐기물인 CKD를 시멘트 원료로 재사용하기 위해 공정 방해물질로 작용하는 KCl을 추출한 폐수이며, 폐수처리시설 증설 등의 문제로 추출액 무방류 및 이를 재이용하고자 하였다. 이온교환법을 적용하여 KCl을 제거한 결과, 이온교환 후 추출액의 pH는 12.7에서 pH 2 미만으로 감소하였으며 양이온교환수지의 H⁺가 이온교환을 거쳐 추출액에 용해되었음을 확인하였다. 이온교환의 선택성에 의해 Ca²⁺, K⁺ 순서로 제거되었으며, K⁺ 이온을 제거하기 위해 접촉시간의 증가가 필요함을 판단하였다. 이온교환수지와 직접접촉시간이 약 6배 높은 접촉시간을 갖는 회분식장치에서 연속흐름식장치 대비 4배 높은 K⁺ 제거 효율을, 7배 높은 Cl^- 제거 효율을 확인하였다. 양이온교환수지의 H⁺가 음이온교환수지의 OH^- 대비 1.2배 빠른 교환속도를 가짐을 추출액 pH 변화를 통해 확인하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권6호
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• pp.471-475
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• 2004

The Oligomeric proanthocyanidin (OPC) in green and black tea, grape seeds, grapes and wine has raised much attention but that OPC in wild grape seed remains to be intensively investigated. This study investigated the total OPC contents and total antioxidant activity of wild grape seeds and developed an efficient extraction process with various temperatures, solvent compositions and times. Also, a chromatography column packed with the Dia-ion HP-20 resin was used for further purification of the ope. The total OPC contents were determined with the Folin-Ciocalteu reagent, and the antioxidant activity using total antioxidant potential (TAP) and 1,1-dipheny|-2picrylhydrazy| (DPPH). The yield of final purified OPC was 1.78 (+)-catechin equivalent (CE) g/100 g, with $IC_{50}$ activities of TAP and DPPH of 31.60 and $15.70\;{\mu}\;g/mL$. These activi­ties of the final purified OPC were about two times higher than that of the BHA used as a refer­ence sample.

• Journal of Applied Biological Chemistry
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• 제51권1호
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• pp.36-44
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• 2008

Organic forms of arsenic (As) were determined through fractionation procedure of soil organic matter (SOM) in soil, sediments and mine tailing samples from the Myungbong, Dongil, and Okdong mining areas of southern Korea. An alkaline extraction method was applied to soil samples followed by the fractionation procedures of SOM by the DAX-8 and XAD-4 resin adsorption method. Major fraction of organic As species (42% to 98%) was found in acid-soluble fraction, whereas minor fraction (0.1 % to 67.8%) was present in the humic-associated As. In acid-soluble fractions, the transphillic- and hydrophilic-associated As were dominant in addition to As binding with humic and fulvic SOM. Arsenic binding was the strongest between pH 6 to 8 and reduced to about 70% at both low and high pH regions. The amount of both transphillic and hydrophillic associated As was less changed than humic and fulvic-associated As, in both low and high pH regions. This apparently indicates that As has stronger affinity towards hydrophillic rather than hydrophobic organics. From the experimental observation of As-binding SOM in natural soil, the ligand exchange model may be a feasible explanation of transphillic and hydrophillic affinity of As.

• Toxicological Research
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• 제16권4호
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• pp.285-291
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• 2000

So far, investigation of environmental pollution has been achieved in field study. This remains the most exhaustive approach, current dimensions of environmental researches and their inherent complexity require that relatively inexpensive and simple laboratory procedures are developed to make possible the screening of large numbers of sites and samples. At this point. microbioassay has been high-lighted. The purpose of this study is to evaluate the water pollution using microbioassay. Two microbioassay methods were optimized and validated for the sensitive and quantitative determination of total toxic effects in the water. EROD(Ethoxyresorufin-O-deethylase) microbioassay was focused to detect PARs, PCBs and dioxinlike components in the water and E-screen assay to xenoestrogens. The EROD microbioassay was executed in rat hepatoma cell line, H4IIE and E-screen assay in MCF7-BUS cell line. Kumho river was selected for this study. 5ι of river water was extracted using combined solid-phase extraction in static adsorption mode with soxhlet extraction. Pollutants adsorbed to the XAD-4 resin were recovered by elution with ethyl acetate and methylene chloride (1 : 9). Toxic effects of extracts were determined by EROD-microbioassay and E-screen assay. EROD activities of water samples were 7.24-72.24 ng/ι MEQ. The estrogenic effect of various water samples is quantitatively evaluated by EEQ. The EEQ of samples range from 0.05 to 6.07 ng-EEQ/ι. These results suggested that Kumho river was highly polluted with organic toxic chemicals.

• 대한치과교정학회지
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• 제19권2호
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• pp.145-153
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• 1989

The causes of the missing teeth are classified as congenital missing, trauma and extraction due to dental caries, variable problems are occured clinically by the missing teeth. The missing of the upper incisors especially would assume a serious aspect, and could be treated by three methods of orthodontic treatment, prosthodontic treatment and autotransplantation of the premolar teeth. The patient of this report had the skeletal class II malocclusion with the left upper central incisor missing, and have been treated with the fixed appliance after extraction of the right upper central incisor and both lower second premolars. The results were obtained as follows: 1. Treatment was done for 1 year 6 months. 2. Normal overbite and overjet were achieved. 3. Cuspal interdigitation was obtained normally. 4. Space problem was resolved with resin restoration of the upper lateral incisors. 5. The upper canines were used as the upper laterals after cuspal contouring. 6. Retention would be required with adequate retainers for a long time to prevent relapsing after treatment.

• Journal of the Korean Wood Science and Technology
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• 제36권5호
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• pp.49-55
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• 2008

This study was carried to investigate the effects of steaming and four different drying methods on the longitudinal liquid permeability of Korean pine (Pinus koraiensis Sieb.et Zucc.) board. Four drying methods were air drying, conventional kiln drying, microwave-vacuum drying and high temperature drying. Darcy equation was used for calculating the specific permeability of the small sapwood specimens taken from the treated boards while capillary rising method was used for the heartwood specimens. The sapwood specimens were extracted with water and benzene-alcohol solution to examine the mechanism of liquid flow in treated wood. No significant correlation was found between specific permeability and the number of resin canals of the sapwood specimens. Extraction decreased the differences of specific permeabilities of the sapwood specimens between the five treatment methods. The effects of extraction on the longitudinal permeability are different between five treatments. The fluid path in heartwood was observed by dynamic observation method.

• 약학회지
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• 제28권2호
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• pp.61-67
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• 1984

A method is described for the spectrophotometric determination of platinum (IV) with 2-oximino-1-indanone based on solvent extraction of Pt:2-oximino-1-indanone complex. The 2-oximino-1-indanone reacted with Pt(IV) to form a dark-orange complex which shows a characterisic maximum absorption at 342nm. The optimum PH for the platinum extraction lies between 5.4~8.0. Beer's law obeys up to 0.98-16.3ppm of platinum (IV) and the molar absorption coefficient is $1.06{\times}10^{-4}L.mol^{-1}.cm^{-1}$. The relative standard deviation of the method was $\times2.1%$. The composition of the complex is estimated to be Pt : In= 1 : 1, by the mole ratio method and ion exchange resin experiment. The optimum condition for the determination of platinum has been studied in detail. The 2-oximin-1-indanone is found to be a selectivereagent for the determination of platinum, since the synthesixed 2-oximino-1-indanone did not react with other metals such as cobalt, cadmium, copper, manganese nickel, iron, lead and zinc, to form the complex. In this studies, we have also clarified Sindhwani and Singh's spectrophotometric determination data of various metals with acenaphthenequinone monooxime (Talanta 20,248, 1973), whose results were not correct.