• 한국잠사곤충학회지
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• 제40권1호
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• pp.17-22
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• 1998

To investigate the detoxificative effect of tea, five kinds of tea(mulberry, anaerobic treated mulberry, green, barly tea and corm tea) were selected and determined their dotoxication activities for Cd and Pb in drinking water. The effect of tea on the removal of Cd and Pb were increased proportionally to the contents of teas. Anaerobic treated mulberry leaf tea showed stronger detoxication activity than the others. In drinking water contaminated with Cd, the removal effect of Cd was high 27% by anaerobic treated mulberry leaf tea and 14% by mulberry leaf tea as compared to green tea. Also, in drinking water with Pb, the removal effect of anaerobic treated mulberry leaf tea was the best among five kinds of tea. Pretreatment method on the removal effect of Cd was better than post-treatment method in the treatment method.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.285-288
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• 2012

• 자원리싸이클링
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• 제27권4호
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• pp.36-43
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• 2018

폐 니켈-카드뮴 전지의 재활용을 위하여 효율적으로 카드뮴과 니켈을 분리할 수 있도록 이온치환 반응을 이용하여 선택적으로 카드뮴을 분리하였다. 폐 니켈-카드뮴 전지 내의 전극을 분쇄하여 얻은 전극 분말을 황산에 침출시킨 니켈-카드뮴 용액에 황화나트륨을 첨가하여 CdS로 침전시켰다. 다양한 조건에서 이온치환실험을 실시하였으며, 최적조건으로는 상온에서 용액의 pH = -0.1, $Na_2S/Cd=2.3$일 때 용액 내 잔존하는 Cd은 약 100 ppm으로 대부분 CdS로 침전된 결과를 얻을 수 있었다.

• 한국환경농학회지
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• 제27권4호
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• pp.382-388
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• 2008

This study was initiated to elucidate the relation between the toxicity of $Cr^{6+}$, $Zn^{2+}$, and $Cd^{2+}$ and sludge age (Solids retention time, SRT). The effect of SRT on the toxicity of $Cr^{6+}$, $Zn^{2+}$, and $Cd^{2+}$ in activated sludge system was investigated with INT-dehydrogenase assay. Experimental results showed that the inhibitory effects of $Cr^{6+}$, $Zn^{2+}$, and $Cd^{2+}$ were reduced as the sludge age increased from SRT 5 d to SRT 25 d. It is noteworthy that the experimental results enabled to determine the relative toxicity of the tested metals depending on the sludge age. At the SRT of 5 and 9 days, the order of toxicity of the three metals to the activated sludge was $Cr^{6+}$ > $Zn^{2+}$ > $Cd^{2+}$ (the $IC_{50}$ value of $Cr^{6+}$, $Zn^{2+}$, and $Cd^{2+}$ was 16.15, 25.90, and 32.49 mg/L, respectively) and $Zn^{2+}$ > $Cr^{6+}$ > $Cd^{2+}$ (the $IC_{50}$ value of $Cr^{6+}$, $Zn^{2+}$, and $Cd^{2+}$ was 39.12, 27.93, and 42.31 mg/L, respectively), respectively. However, the toxicity of three metals was almost same at the SRT of 14 and 25 days (the range of $IC_{50}$ in SRT 14 and 25 days was from 49.80 mg/ L to 53.44 mg/L among three heavy metals). This results would be explained by that the quantity of biopolymer formed in short SRT was small, whereas that in long SRT was large. Consequently, it is recommended that sludge age be maintained at long SRT in order to avoid the toxicity inhibition of heavy metals such as $Cr^{6+}$, $Zn^{2+}$, and $Cd^{2+}$.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2003년도 학술대회지
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• pp.27-27
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• 2003

• The Korean Journal of Ecology
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• 제27권4호
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• pp.231-237
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• 2004

In this research we determined the levels of heavy metals in soil and metal-accumulating plants from a D military shooting site in the Kyungkido district of Korea. The data obtained may be useful in the development of methods for the efficient phytoremediation of contaminated soil. The total Cd, Cu, Pb, and Zn concentrations in the soil were found to be 1.67-5.04 mg/kg, 52.51-106.26 mg/kg, 37.24-90.32mg/kg, and 111.45-188.19mg/kg, respectively. These results show that the soil is contaminated with Cd and Cu, and this contamination is particularly severe in the case of Cd because of its high bioavailability (25-57% of the total metal in the soil is exchangeable). The high concentrations of heavy metals in the shoots of Persicaria thunbergii and Artemisia princeps var. orientalis indicate that these plants (all perennial herbs) accumulate heavy metal efficiently. Further, these plants were found to contain more Cd in its shoots (＞60% of the total metal found in the plant) than any other plant; these results indicate that these native species are particularly suited to use in Cd phytoextraction.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제27권3호
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• pp.146-157
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• 2024

Purpose: Celiac disease (CD) is one of the most prevalent food-related illnesses in children, with a global prevalence of approximately 1.4%. CD can create an emotional burden, particularly on mothers, who are mainly responsible for managing challenges related to adherence to a gluten-free diet, high food costs, and food problems in schools and social areas. There is a gap in the literature, and parental experiences of raising children with CD should be explicitly examined. This qualitative study sought to provide insights into the experiences of parents raising a child with CD in the Turkish context. Methods: This study used a descriptive qualitative research methodology and conducted individual semi-structured video-based dyadic interviews with 19 parents. Results: Participants experienced both challenges and motivators through management of their children's CD. Analyses of the interview transcripts through the data uncovered three main themes focusing primarily on parental concerns: (1) parental challenges in child's disease management, (2) supportive care needs, and (3) parental expectations. Conclusion: A multidisciplinary team should approach the child and family immediately after diagnosis, and facilities should support parents with continuing education and psychological, financial, and social assistance.

• International Journal of Quality Innovation
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• 제6권2호
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• pp.105-115
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• 2005

In recent years, high-speed recording CD-R has already become the mainstream of CD-R market. Therefore, to promote the efficiency of recording CD-R is of significant importance. This study uses Taguchi's parameter design to improve the yield rate for the process of CD-R substrate. We have found 13 three-level controllable factors from the fishbone diagram, repeated 10 times the experiment with the L27(313) orthogonal array, and measured seven quality characteristics. We employ four general methods to find the optimal parameter conditions individually. Then, we perform the confirmation experiment and compare the results. Finally, we obtain the optimal parameter conditions. According to the analysis of benefits, the optimal parameter conditions can reduce the quality loss of CD-R substrate to about 21%. In the future, the results can be extended to other research of DVD-R substrate.

• 한국환경농학회지
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• 제12권2호
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• pp.105-111
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• 1993

경상북도 울진군 북면 덕구동과 칠곡군 동명면 덕명동에 소재한 2개 아연광산 인근 지역에서 채취한 토양과 야생식물체중의 Cd, Cu, Zn의 함량을 조사한 결과는 다음과 같다. 1. 생육기간에 따른 야생식물체중 중금속함량은 Cd는 다년생, 월년생, 1년생의 순위로, Cu는 1년생, 다년생, 월년생의 순위로 낮았으며, Zn은 다년생, 월년생, 1년생 모두 비슷하였다. 2. 중금속함량이 가장 높은 야생식물은 Cd의 경우 고비(다년생)였으며, Cu의 경우는 쇠뜨기(월년생), Zn의 경우는 고마리(1년생)이었지만, 조사된 식물체중 Cd, Cu, Zn 각 함량이 다 높았던 것은 고마리였다. 3. 야생식물의 과별 중금속함량은 Cd는 고사리과에서, Cu는 속새과에서, Zn는 마디풀과에서 가장 높았다. 4. 고마리와 망초의 식물체 부위별로 Cd 와 Zn의 함량은 잎, 줄기, 뿌리의 순위로 낮았는데 반하여, Cu는 뿌리, 잎, 줄기의 순위로 낮았다. 5. 토양중 Cd, Cu, Zn의 평균함량(범위)은 칠곡지역에선 1.27($0.45{\sim}2.75$)ppm, 12.04($3.00{\sim}33.20$)ppm, 64.28($8.14{\sim}209.79$)ppm 이었으며, 울진지역에선 3.30($0.50{\sim}9.52$)ppm, 72.93($47.75{\sim}118.35$)ppm, 194.04($41.37{\sim}520.96$)ppm이었다. 6. 토양중의 중금속(Cd, Cu, Zn 등) 함량과 식물체중 중금속 함량간에는 유의성은 없었으나, 정의 상관관계를 보였다. 7. 고비, 고마리, 쇠뜨기 등은 중금속(Cd, Cu, Zn)의 흡수력이 큰 야생식물로서 중금속 및 Zn 오염토양에서 중금속 제거에 효과가 클 것으로 사료된다.

• 태양에너지
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• 제11권3호
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• pp.74-83
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• 1991

본 논문은 substrate의 온도를 $200{\pm}1^{\circ}C$ 정도로 유지하며 진공저항 가열 증착법을 이용하여 (p)ZnTe/(n)Si 태양전지와 (n)CdS-(p)ZnTe/(n)Si 복접합 박막을 제작한 후 그 전기적 특성을 조사, 비교하였다. 제작한 (p)ZnTe/(n)Si 태양전지와(n)CdS-(p)ZnTe/(n)Si 복접합 박막에 대하여 $100[mW/cm^2]$의 광조사 하에서 특성을 조사한바 다음과 같은 결과를 얻었다. 단략전류$[mA/cm^2]$ (p)ZnTe/(n)Si:28 (n)CdS-(p)ZnTe/(n)Si:6.5 개방전압[mV] (p)ZnTe/(n)Si:450 (n)CdS-(p)ZnTe/(n)Si:250 충실도, FF (p)ZnTe/(n)Si:0.65 (n)CdS-(p)ZnTe/(n)Si:0.27 변환효율[%] (p)ZnTe/(n)Si:8.19 (n)CdS-(p)ZnTe/(n)Si:2.3 제작된 박막은 열처리에 의해 성능이 향상되지만 (p)ZnTe/(n)Si 태양전지는 약 $470^{\circ}C$ 이상의 온도와 15분 이상의 열처리 시간에서 그리고 (n)CdS-(p)ZnTe/(n)Si 복접합 박막은 약 $580^{\circ}C$ 이상의 온도와 15분 이상의 열처리 시간에서는 박막의 각종 구조결함으로 인한 감소현상을 나타내었다. 열처리 온도의 증가에 따라 박막의 표면저항은 감소하였다.