• Nuclear Engineering and Technology
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• 제56권9호
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• pp.3608-3615
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• 2024

This study introduces a lead-free alternative for enhanced radiation protection. While lead aprons effectively attenuate ionizing radiation, concerns regarding flexibility, weight, and environmental hazards persist. In response, the present research is focused on producing an innovative sheet shielding comprised of carefully selected dense metal oxide microparticles (DMOs-MPs) and liquid silicone rubber (LSR). To evaluate the efficacy of the LSR samples, the current study uses rigorous testing procedures, such as microstructure characterization using EDX and FESEM. Furthermore, the study investigated key attenuation parameters within the LSR samples. Radiation protection was greatly and effectively supplied using DMOs-MPs filler (Bi-1 to Bi-7) in LSR samples; this protection reached 99.9% in the X-ray energy range. Due to the unique characteristics of the Bi-7, the results demonstrated that the samples' shielding efficiency improved with the addition of high atomic number and high-density fillers. It had the greatest attenuation coefficient and density. At 60 keV, Bi-7's density was 2.980 gcm^-3, and its LAC and MAC were 19.2621 cm^-1 and 6.4638 cm²/g, respectively. It also had the lowest half-value layer values in the energy range of 60-120 keV. The LSR samples showed effective radiation absorption for different energy levels, indicating that LSR can enhance the flexibility and comfort of the apron while providing adequate radiation protection. The incorporation of the DMOs-MPs with LSR represents an effective contribution and a noteworthy stride to enhance the safety and well-being of medical professionals routinely exposed to ionizing radiation.

• 한국산림과학회지
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• 제90권4호
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• pp.495-504
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• 2001

본 연구는 포플러 4개 수종의 체내 부위별 Cd과 Pb 축적 특성을 이해하고, 균근 형성이 중금속 흡수에 미치는 영향을 밝히고자 수행하였다. 외생균근균인 모래밭버섯균(Pisolithus tinctorius)을 현사시나무(Populus alba${\times}$glandulosa), 수원포플러(P. koreana${\times}$nigra var. italica), 양황철(P. nigra${\times}$maximowiczii), 이태리포플러(P. euramericana)의 삽수에 접종하여 화분에서 생장시켰다. 화분은 균근균 접종구와 비접종구로 구분하였으며, Cd은 토양에 0, 30, 80ppm으로, 그리고 Pb은 0, 50, 300ppm으로 처리하였다. 가을까지 야외에서 생육시킨 다음, 수확 후 총 생체량, Shoot/Root율, Cd과 Pb의 농도를 부위별로 측정하였다. 모래밭버섯균을 접종한 이태리포플러는 Cd과 Pb 처리 모두에서 비접종구보다 총 생체량이 증가하였으나, 나머지 세 수종에서는 접종 효과가 없었다. 균근균 접종으로 수원포플러와 이태리포플러의 S/R율은 증가하였다. 현사시나무는 포플러 4개 수종 중 Cd을 가장 높은 농도로 축적하였으며, 균근균 접종은 Cd 축적 농도를 4배정도 증가시켰다. 현사시나무는 잎, 줄기, 뿌리 중에서 잎에 가장 높은 농도로 Cd을 축적한 반면 다른 세 수종은 뿌리에 가장 높은 농도로 축적하였다. 그러나 Pb 축적 농도는 4개 수종 중에서 현사시나무가 가장 낮았다. Pb의 축적은 포플러 4개 수종모두뿌리에서 가장 높았으나 수원포플러는 잎에도 뿌리만큼 축적하였다. 균근균을 접종하지 않은 경우 Pb의 축적은 이태리포플러에서 가장 높았으나, 균근균을 접종할 경우 수원포플러에서 Pb 축적이 2배 이상 증가하였다. 결론적으로 현사시나무는 토양으로부터 Cd을 흡수하는데 효과적인 수종이며 이태리포플러는 Pb을 효과적으로 흡수한다. 균근균을 접종하면 현사시나무의 경우 Cd을 4배, 수원포플러의 경우 Pb을 2배 이상 더 흡수할 수 있고, 이 두 수종은 잎에 중금속을 축적하므로, 낙엽을 수거한다면 중금속 오염 토양의 생물 정화용으로 이용이 가능하다고 결론 짓는다.

• Ecology and Resilient Infrastructure
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• 제7권4호
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• pp.262-273
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• 2020

본 연구에서 사용한 바이오폴리머 (biopolymer)는 친환경 제방 건설 소재로 연구 되고 있다. 이러한 바이오폴리머를 토양에 혼합할 경우 이온결합 및 수소결합을 통해 토양의 강도 증진 효과가 잘 알려져 있지만 바이오폴리머와 혼합된 토양이 식물에 미치는 영향은 자세히 알려져 있지 않다. 본 연구는 Zn 과잉 스트레스 조건에서 바이오폴리머의 토양 혼합이 Camelina sativa L. (Camelina)에 미치는 영향을 분석 하였다. Camelina의 생장실험을 기반으로, Zn 과잉 스트레스에 대한 최적의 바이오폴리머 혼합 비율은 0.5%로 결정하여 연구를 진행하였다. Zn 과잉 스트레스 하에서, BG 또는 XG 혼합구의 Camelina는 바이오폴리머 비혼합구에 비해 높은 생장을 보였으며, Zn 과잉 스트레스 피해 지표인 Malondialdehyde (MDA) 함량과 전해질유출도의 감소를 나타냈다. 바이오폴리머의 Zn 결합능을 DTZ (1,5-diphenylthiocarbazone)을 이용하여 분석한 결과, BG 또는 XG 모두 명확한 Zn 흡착 반응을 보였다. DTZ 염색 및 ICP-OES 분석에서, Zn 과잉 스트레스에 의한 Camelina의 Zn 흡수량이 BG 또는 XG 혼합에 의해 현저히 감소함을 확인하였다. 그리고, BG 또는 XG의 혼합은 Camelina의 중금속 수송체 Heavy metal ATPase (HMA)의 발현을 유도하지 않았으며, 야생형 (wildtype, WT)보다 CsHMA3가 과발현 된 Camelina에서 BG 또는 XG 혼합구와 유사한 수준의 Zn 과잉 스트레스 저감 효과를 확인하였다. 결론적으로, 바이오폴리머의 토양 혼합은 바이오폴리머와 Zn 사이의 결합에 의해 Camelina에 과도한 Zn 이온이 흡수되는 것을 방지하여 Zn 독성 피해를 감소시키는 것으로 확인되었다. 더 나아가 바이오폴리머의 토양혼합은 제방강화뿐만 아니라 중금속으로 오염된 토양에서 식물 생존에 긍정적으로 작용할 것이라 판단된다.

• 한국환경농학회지
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• 제15권1호
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• pp.1-10
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• 1996

토양 중 중금속들의 이동성 및 식물 흡수와의 관계를 알기 위하여 제련소 매연 및 분진의 영향을 받는 논 토양을 대상으로 1982년과 1990년에 토양 시료를 표 ${\cdot}$ 심토 별로 채취하여 치환성, 묽은산, 유기물 결합형, Fe-Mn산화형결합, 잔류형(규산염형)으로 추출 방법을 달리하여 토양 중 중금속 함량 및 존재 형태를 분류하고, 1990년도 토양 시료 중 중금속 함량과, 1990년도에 채취한 수도체 중 부위별 중금속 함량과 상관관계를 조사 분석한 결과는 다음과 같다. 각 토양중 중금속 전 함량은 1990년 함량이 1982년도 함량보다 표토에서 Cd가 12%, Zn 44%, Cu가 40%, Pb가 4% 증가하였고, 심토에서는 Cd가 12%, Zn 40%, Cu가 60%, Pb가 57%로 증가되었고, 이들의 증가 비율이 Cu > Zn> Pb > Cd의 순서를 나타내었으며, Cd의 경우 잔류형(규산염형태) >치환성 >묽은산 추출형 순으로 함량 변화가 나타났고 9년 사이에 38-71%의 증가 비를 나타내었다. 산화물 및 규산염내에 결합되어 있어 비이동성인 중금속 비율은 표토에서 Cd가 31.65%, Pb가 44.22%, Cu가 76.57%, Zn이 79.49%였고 치환성, 묽은산 추출형 및 유기적 결합형 등의 이동성은 20.28% 이상으로 Cd의 경우 68.35%, Pb의 경우 55.78%, Cu 23.43%, Zn이 20.28% 순으로 나타났다. 표토 중 중금속 함량과 수도체 부위별 함량간에는 왕겨 및 현미를 제외하고, 엽신, 엽초, 줄기, 화서축과 유의성 있는 상관관계가 있었으나, 심토 중 중금속 함량과 수도체 부위별 함량간에는 유의성이 없었다. 표토 중 추출 형태별 중금속 함량과 수도체 부위 함량간의 상관관계는 묽은산 추출형 및 유기물 결합형에서 상관관계가 많이 있었으나, 심토에서는 없었다.

• 한국환경과학회지
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• 제2권2호
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• pp.123-133
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• 1993

Shingal reservoir is a relatively small (211ha) and shallow impoundment, and approximately 25 ha of its sediment is exposed after spring drawdown. At least 14 vascular p13n1 species germinate on the exposed sediment, but Persimria vulgaris Webb et Moq. quickly dominates the vegetation. In order to estimate the role of the vegetation in the dynamics of heavy metal pollutants in the reservoir, Cu concentration of water, fallout particles, exposed sediment, and tissues of p. vulgaris, Ivas analyzed. Cu content in reservoir water decreased from $13.10mg/m^2$ on May 15 (before dralvdown) to $3.08mg/m^2$ in June 1 (after drawdown), mainly due to the loiwering of water level. Average atmospheric deposition of Cu by fallout particles was $10.84 {\mu}g/m^2/day$. Cu content in the surface 15cm of exposed sediment decreased from $5.094g1m^2$ right after drawdown, to $0.530g/m^2$ in 41 days, which is a 89.6% decrease. Therefore up to 99.7% of Cu in the reservoir appears to exist in the sediment. only 0.3% in water If the rate of atmospheric Input by fallout particles is assumed to have been the same since 1958, when the reservoir was completed, cumulative input of Cu during the 38 years would have been $150.35mg/m^2$, which is only 3.0% of Cu content in sediment right after drawdown. Therefore, most of Cu in the Shingal reservoir must have been transported by the Shingal-chun flowing into the reservoir, Standing crop of vegetation on the exposed sediment 41 days after drawdown was $730.67g/m^2$, of which 630.91g/m2 was p. vulgaris alone, and Cu content in P vulgaris at this time was $6.612mg/m^2$. This was only 0.13% of Cu in the exposed sediment, but was 50.5% of Cu in water before drawdown, or 167% of the average annual input of Cu by atmospheric deposition. If other plants were assumed to absorb Cu to the same concentration as p. vulgaris, total amount of Cu absorbed in 41 days by vegetation on the exposed sediment is estimated to be 1913.3 g, which is a considerable contribution to the purification of the reservoir water.

• 한국환경과학회지
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• 제2권2호
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• pp.29-29
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• 1993

Shingal reservoir is a relatively small (211ha) and shallow impoundment, and approximately 25 ha of its sediment is exposed after spring drawdown. At least 14 vascular p13n1 species germinate on the exposed sediment, but Persimria vulgaris Webb et Moq. quickly dominates the vegetation. In order to estimate the role of the vegetation in the dynamics of heavy metal pollutants in the reservoir, Cu concentration of water, fallout particles, exposed sediment, and tissues of p. vulgaris, Ivas analyzed. Cu content in reservoir water decreased from $13.10mg/m^2$ on May 15 (before dralvdown) to $3.08mg/m^2$ in June 1 (after drawdown), mainly due to the loiwering of water level. Average atmospheric deposition of Cu by fallout particles was $10.84 {\mu}g/m^2/day$. Cu content in the surface 15cm of exposed sediment decreased from $5.094g1m^2$ right after drawdown, to $0.530g/m^2$ in 41 days, which is a 89.6% decrease. Therefore up to 99.7% of Cu in the reservoir appears to exist in the sediment. only 0.3% in water If the rate of atmospheric Input by fallout particles is assumed to have been the same since 1958, when the reservoir was completed, cumulative input of Cu during the 38 years would have been $150.35mg/m^2$, which is only 3.0% of Cu content in sediment right after drawdown. Therefore, most of Cu in the Shingal reservoir must have been transported by the Shingal-chun flowing into the reservoir, Standing crop of vegetation on the exposed sediment 41 days after drawdown was $730.67g/m^2$, of which 630.91g/m2 was p. vulgaris alone, and Cu content in P vulgaris at this time was $6.612mg/m^2$. This was only 0.13% of Cu in the exposed sediment, but was 50.5% of Cu in water before drawdown, or 167% of the average annual input of Cu by atmospheric deposition. If other plants were assumed to absorb Cu to the same concentration as p. vulgaris, total amount of Cu absorbed in 41 days by vegetation on the exposed sediment is estimated to be 1913.3 g, which is a considerable contribution to the purification of the reservoir water.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2010년도 제3회 국제학회
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• pp.40-40
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• 2010

Studies on attractive color changing property of dye chromophore and fluorophore have been greatly enjoyed in the related industrial and research fields such as optoelectronics, chemosensor, biosensor and so on. The optical property based on D-$\Pi$-A intramolecular charge transfer (ICT) system of chromophore molecules can be utilized as suitable sensing probes for checking media polarity and determining colorimetric chemosensing effect, especially heavy metal detection. These finding are obtained by absorption and emission properties. In this work, donor-acceptor D-$\Pi$-A type fluorescent dyes were designed and synthesized with the corresponding donor and acceptor groups. The selected donor moieties might be provided prominent amorphous properties which are very useful in designing and synthesizing functional polymers and in fabricating devices. Another reasons to choose are commercial availabilities in high purity and low price. Donor-bridge-acceptor (D-A) type dyes can produce impressive optical-physical properties, yielding them potentially suitable for applications in the synthesis of small functional organic molecules. Small organic functional molecules have unique advantages, such as better solubility, amorphous character, and represent an area of research which needs to be explored and developed. Currently, their applications in metalorganic compounds is rapidly expanding and becoming widespread in self-assembly processes, photoluminescence applications, chiral organocatalysts, and ingrafts with nanomaterials. Colloidal nanoparticles have received great attentions in recent years. The photophysical properties of nanoparticles, particularly in terms of brightness, photostability, emission color purity and broad adsorption range, are very attractive functions in many applications. To our knowledge background, colloidal nanoparticles have been enjoyed their applications in bio-probe research fields. This research interest can be raised by the advantages of the materials such as high photoluminescence quantum yields, sharp emission band, long-term photostability and broad excitation spectra. In recent, the uses of nanoparticles being embedded in a polymer matrix and binded on polymer surface have been explored and their properties such as photo-activation and strong photoluminescence have been proposed. The prepared chromophores and nanoparticles were investigated with absorption and emission properties, solvatochromic behaviors, pH induced color switching effects, chemosensing effects and HOMO/LUMO energy potentials with computer simulation. In addition, synthesized fluorophore dyes and particles were applied onto PE/Aramid fiber fluorescing colorations. And the related details were then discussed.

• 한국자원식물학회지
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• 제26권1호
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• pp.68-74
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• 2013

본 연구는 중금속으로 오염된 논토양에서 비소 흡수능이 우수한 봉의꼬리(Pteris multifuda)를 재배할 때 차광처리가 봉의꼬리의 생육과 토양 내 비소 흡수에 미치는 영향을 분석하기 위하여 수행하였다. 비소로 오염된 (구)장항제련소 인근의 논토양에서 수행하였으며, 각 실험구의 크기를 $2{\times}2m$로 조성하였고, 동일한 생육단계의 봉의꼬리를 $20{\times}20cm$ 간격으로 식재하여 24주간 재배하였다. 차광조건에 따른 봉의꼬리의 생육을 조사하였고, 식물체 내 비소 축적량 및 토양의 비소 변화량은 ICP를 이용하여 분석하였다. 연구의 결과, 중금속으로 오염된 논토양에서 차광에 의한 봉의꼬리의 생육은 무차광에 비해 차광 처리구에서 왕성하였다. 봉의꼬리 지상부의 비소 축적량은 차광($140.9mg{\cdot}kg^{-1}$)에 비해 무차광 처리구($169.8mg{\cdot}kg^{-1}$)에서 다소 높았으며, 지하부의 비소 축적량은 비슷한 경향을 보였다. 그러나 생육은 70% 차광 처리구에서 월등히 우수하여, 토양에서 흡수한 비소의 함량은 차광처리구에서 오히려 더 많았다. 봉의꼬리의 비소 이동계수(TR)는 차광처리에 관계없이 0.87~0.89로 매우 높아 흡수한 비소를 지상부로 빠르게 이동시키므로 생육 후 지상부의 제거처리에 의해 토양 내의 비소를 효과적으로 제거할 수 있으리라 생각된다.

• 한국토양비료학회지
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• 제48권5호
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• pp.332-339
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• 2015

The objective of this study was to evaluate the effectiveness of different biochars on the removal of heavy metals from aqueous media. The experiment was carried out in aqueous solutions containing $200mg\;CdL^{-1}$ or $200mg\;PbL^{-1}$ using two different biochars derived from soybean stover and orange peel (20 mg Cd or $Pbg^{-1}$ biochar). After shaking for 24 hours, biochars were filtered out, and Cd and Pb in the filtrate were analyzed by flame atomic absorption spectrophotometer (FAAS). In order to provide information regarding metal binding strength on biochars, sequential extraction was performed by modified SM&T (formerly BCR). The results showed that 70~100% of initially added Cd and Pb was adsorbed on biochars and removed from aqueous solution. The removal rate of Pb (95%, 100%) was higher than that of Cd (70%, 91%). In the case of Cd, orange peel derived biochar (91%) showed higher adsorption rate than soybean stover derived biochar (70%). Cd was adsorbed on the biochar mainly in exchangeable and carbonates fraction (1st phase). In contrast, Pb was adsorbed on it mainly in the form of Fe-Mn oxides and residual fraction (2nd and 4th phase). The existence of Cd and Pb as a form of surface-precipitated complex was also observed on the surfaces of biochars detected by field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectrometer (EDAX).

• 한국환경보건학회지
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• 제47권1호
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• pp.64-77
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• 2021

Objective: Biological monitoring of trace elements in human blood samples has become an important indicator of the health environment. The purpose of this study was to detect and evaluate multiple metal items in blood samples based on ICP-MS, to perform comparative evaluation with the existing analysis method, and to develop and verify a new method. Methods: 100 μL of whole blood from 80 healthy subjects was used to analyze ten metals (Sb, tAs, Cd, Pb, Mn, Hg, Mo, Ni, Se, Tl) using ICP-MS. Verification of the analysis method included calculation of linearity, accuracy, precision and detection limits. In addition, a comparative test with the conventional graphite furnace atomic absorption spectroscopy (GF-AAS) method was performed. In the case of Pb, Cd, and Hg in whole blood, cross-analysis between Pb, Cd, and Hg analysis methods was performed to confirm the difference between the existing method and the new method (ICP-MS). Results: The coefficient of determination (R2) was 0.999 or higher in seven items and 0.995 or higher in three items. The Pb result showed that Pearson's correlation coefficient was very high at 0.983, and the intraclass correlation coefficient was 0.966. The Cd result showed that Pearson's correlation coefficient was 0.917 between the existing method and the new analysis concentration value. Its intraclass correlation coefficient was 0.960, and there was no significant difference between the two groups. Hg had a low correlation at 0.687, and the intraclass correlation coefficient was 0.761, which was lower than that of Pb and Cd. The intra-day and inter-day accuracy of Pd and Cd were satisfactory, but Hg did not meet the criteria for both accuracy and precision when compared with the conventional analysis method. Conclusion: This study can be meaningful in that it proposes a more efficient and feasible analysis method by verifying a blood heavy metal concentration experiment using multiple simultaneous analyses. All samples were processed and analyzed using the new ICP-MS. It was confirmed that the agreement between the two methods was very high, with the agreement between the current and new methods being 0.769 to 0.998. This study proposes an efficient simultaneous methodology capable of analyzing multiple elements with small samples. In the future, studies of various applications and the reliability of ICP-MS analysis methods are required, and research on the verification of accurate, precise, and continuous analysis methods is required.