• 한국수산과학회지
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• 제9권3호
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• pp.169-175
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• 1976

해수중 ppb 정도의 카드뮴, 구리, 납, 아연 및 수은 정량을 위한 용매추출-원자흡광법 및 환원기화법에 의한 무염원자흡광법을 검토했다. 용매추출 때의 최적 pH는 pH4-7였으며 용매로는 MIBK가 가장 효율이 좋았으며 킬레이트제로는 DDTC가 APDC보다 추출율 및 기타 조건이 유리했다. 즉 $1\iota$ 해수를 사용하여 pH4-5에서 DDTC-MIBK로 추출하여 아세칠렌-공기불꽃 중에 흡입시켜 흡광도를 측정하는 방법으로 해수시료를 분석한 결과 정밀저는 표준편차로 카드뮴 0.058 ppb, 구리 0.084 ppb, 납 0.44ppb였다, 아연은 $1\iota$ 시수를 사용했을 때는 블랭크값이 녀무 크게 나오고 그 정밀도가 극히 좋지 않았다. 시수량을 200ml로 했을 때는 비교적 정밀도가 좋았으며 표준편차로서 2.49 ppb였다. 수은은 시수 500ml을 황산-과망간산칼리움 분해법으로 분해시켜 염화제1주석으로 수은을 환원기화시켜 흡광도를 측정했으며 그 정밀도는 0.005 ppb였다. 이상의 방법으로 측정할 수 있는 각 금속의 정량감도는 카드뮴 $0.08\;ppb/\%$, 구리$0.15\;ppb/1\% $, 납 $0.6\;ppb/1\%$, 아연 $1.2\;ppb/1\%$, 수은 $0.01\;ppb/1\%$였다. 채수후 분석시까지의 시수보관에 따른 각 금속의 농도변화는 시수$1\iota$에 대해 질산 10ml 정도 넣어 pH 1.5 부근으로 하며 플리에칠렌병에서 보관한 결과 카드뮴, 구리, 납, 수은은 30일정도 까지는 안정하였으며 아연은 불규칙한 심한 변동을 보였다.

• 한국환경과학회지
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• 제18권12호
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• pp.1361-1368
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• 2009

The effects of $Cd^{2+}$ ions on the Chl a fluorescence of 5 hydrophytes (e.g. Lemna, Salvinia, Ricciocarp, Nymph, Typha plants) were investigated in order to select $Cd^{2+}$-sensitive plant species and to get informations on physiological responses of plants to $Cd^{2+}$ stress. Lemna plants were most sensitive to cadmium stress, while Nymph plants were tolerant. However, in all $Cd^{2+}$-treated plants, Fv/Fm, the maximum photochemical efficiency of PS II, decreased in proportion to the increase of $Cd^{2+}$ concentration and treatment time. The Chl a fluorescence transient O-J-I-P was also considerably affected by $Cd^{2+}$ ions; the fluorescence yield decreased consid- erably in steps J, I and P in $Cd^{2+}$ treated plants, although it followed a typical polyphasic rise in non-treated plants. In Lemna plants, the functional parameters, ABS/CS, TRo/CS와 ETo/CS and RC/CS, decreased in proportion to the increase of $Cd^{2+}$ concentration, while N, Mo and Kn increased. The structural parameters, ${\Phi}po$, ${\Phi}po$/($1-{\Phi}po$), Plabs, SFlabs, Kp and RC/ABS, also decreased according to the increase of $Cd^{2+}$ concentration. Consequently, Lemna plants will be useful as a experimental model system to investigate responses of plants. And several functional or structural parameters could be applied to determine quantitatively the physiological states of plants under stresses.

• Clinical and Experimental Reproductive Medicine
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• 제47권3호
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• pp.168-179
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• 2020

Objective: This study investigated testicular oxidative stress status and physiomorphological function in Wistar rats fed with yaji and cadmium chloride (CdCl₂). Methods: Sixty male albino Wistar rats (12 per group) were randomly assigned to five groups: group I (control), group II (300 mg/kg.bw of yaji), group III (500 mg/kg.bw of yaji), group IV (2.5 mg/kg.bw of CdCl₂), and group V (2.5 mg/kg.bw of yaji+4 mg/kg.bw omega-3). Each group was evenly subdivided into two subgroups and treatment was administered for 14 days and 42 days, respectively. Semen quality (sperm count, progressive motility, normal morphology, and gonadosomatic index), hormones (testosterone, follicle-stimulating hormone, and luteinizing hormone), testicular oxidative stress markers (superoxide dismutase, catalase, glutathione peroxidase, and malonaldehyde) and testicular histomorphological features were examined. Results: Yaji caused significant (p< 0.05) dose- and duration-dependent reductions in semen quality, the gonadosomatic index, testosterone, follicle-stimulating hormone, and luteinizing hormone. Yaji also caused significant (p< 0.05) dose- and duration-dependent decreases in superoxide dismutase, catalase, and glutathione peroxidase activity, as well as increased testicular malonaldehyde levels. Yaji induced distortions in the testicular histological architecture. CdCl₂ damaged testicular function by significantly (p< 0.05) reducing semen quality, reproductive hormone levels, and oxidative stress markers in albino Wistar rats. CdCl₂ also altered the histology of the testis. Conclusion: This study shows that yaji sauce has similar anti-fertility effects to those of CdCl₂, as it adversely interferes with male reproduction by impairing oxidative stress markers and the function and morphological features of the testis.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.143-146
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• 2004

Natural zeolites have exhibited high sorption capacity for inorganic cations including heavy metals and ammonium. Moreover, they were proven to be effective for environmental applications such as permeable barriers for controlling the spread of cation-contaminated groundwater. However zeolites have little or no affinity for anionic species like chromium, as they possess a net negative structural charge. To achieve the simultaneous sorption for anionic contaminants, surfactant-modified zeolite (SMZ) has been employed as the possible sorbents. Current study focuses on simultaneous removal of heavy metals having different ionic form in aqueous solution, cadmium (C $d^{2+}$) and chromium (Cr $O_{4}$$^{2-}$), using newly developed materials, ZanF. ZanF, a potential alternative to SMZ, was derived from zeolite modified by Fe(II) chloride followed by reduction with sodium borohydride. Batch experiments were performed to estimate the removal efficiency of ZanF at different conditions. Under different pH ranging from 2 to 6, removal efficiency was investigated. And C $d^{2+}$ removal efficiency was estimated by varying background concentration of Cr $O_{4}$$^{2-}$, and vice versa. With the test results, ZanF was expected to be a possible reactive materials alternative to SMZ in permeable reactive barriers (PRBs) for treating the contaminated groundwater with cationic and anionic heavy metals.als.

• 대한화학회지
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• 제19권6호
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• pp.428-433
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• 1975

물중에 ppb 정도로 존재하는 구리, 납, 카드뮴 및 아연을 동시에 정량하기 위하여 디티존-클로로포름 抽出法으로 농축하여 短形波폴라로그래피法으로 측정하는 방법을 검토했다.디티존鹽으로 클로로포름層에 추출된 이들 이온을 , 디티존보다 약간 과량의 수은(II)이온을 함유하는 염산으로 역추출한 후 支持電解質로서 염화칼륨을 가하고 순수한 클로로포름으로 두번 씻은 다음 短形波폴라로그램을 기록한다. 이 방법으로 구리, 납 및 카드뮴은 3ppb까지, 아연은 14ppb까지 상대오차 10%이내로 할 수 있었다.

• Nuclear Engineering and Technology
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• 제54권2호
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• pp.653-660
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• 2022

The interaction between UN and CdCl₂ in the LiCl-KCl molten eutectic was studied at 1023 K. The chlorination was monitored by sampling and recording the redox potential of the medium. At 1023 K the chlorination of UN with cadmium chloride in the molten LiCl-KCl eutectic proceeds completely and results in the formation of uranium chlorides. The melts of the LiCl-KCl-UCl₃ or LiCl-KCl-UCl₄ compositions can be obtained by the end of experiment depending on the presence of metallic cadmium in the reaction zone. The higher the concentration of the chlorinating agent, the faster the reaction rate. At [CdCl₂]/[UN] = 1.65 (10% excess) the reaction proceeds to completion in about 7.5 h. At [CdCl₂]/[UN] = 7 the complete chlorination takes 2.5-3 h.

• 대한화학회지
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• 제57권3호
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• pp.316-321
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• 2013

Electrocoagulation (EC) technique is applied for the treatment of wastewater containing heavy metals ions such as nickle (Ni), lead (Pb) and cadmium (Cd) by using sacrificial anodes corrode to release active coagulant flocs usually aluminium or iron cations into the solution. During electrolytic reactions hydrogen gas evolve at the cathode. All the experiments were carried out in Batch mode. The tank was filled with synthetic wastewater containing heavy metals and efficiency of electro-coagulation in combination with aluminum and iron electrodes were investigated for removal of such metals. Several parameters, such as contact time, pH, electro-coagulant concentration, and current density were optimized to achieve maximum removal efficiency (%). The concentrations of heavy metals were determined by using Atomic Absorption Spectroscopy (AAS). It is found that the electro-coagulation process has potential to be utilized for the cost-effective removal of heavy metals from wastewater specially using iron electrodes in terms of high removal efficiencies and operating cost.

• 대한예방한의학회지
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• 제8권2호
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• pp.81-98
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• 2004

1. The cell viability was determined by MTT method. Their cytotoxic activities against three cancer cell lines such as A549, MDA-MB-231 and SNU-C4 cell line were tested. Among them, The methanol extract of Saururus chinensis Baill. showed the strongest cytotoxic effect against SNU-C4 cells. These results suggest that the methanol extract of Saururus Chinensis Baill. possessed a potential antitumorous agent. 2. In vitro the antitoxic activity of ethanol extract of Saururus Chinensis Bail on NIH 3T3 fibroblasts was evaluate by the MTT (3-(4,5-dimethyl- thiazol-2-yl)-2,5-diphenyl-2H-tetra캐lium bromide) and SRB (sulforhodamine B protein) assays. The number of NIH 3T3 fibroblasts were increased and tend to regenerate. These results suggest that Saururus Chinensis Bail extract retains a potential antitoxic activity. 3. Complexation of Cd (II) ion with ligands such as quercetin has been determined by UV-vis spectrophotometric method in tris buffer solution at various pH. It was found that only 1 : 1 Cd-complex is formed by the interaction between catechol moiety in ring B and cadmium [Cd(II)] in aqueous solution. The spectral parameters for Cd-complex were determined by Beer's law at various pH. It has shown that 1 : 1 Cd-complex has a maximum absorbance and red shift by the alkaline pH.

• 대한화학회지
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• 제31권5호
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• pp.444-451
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• 1987

에틸렌디아민, 프로필렌디아민 및 디에틸렌트리아민의 구리(II), 카드뮴(II) 및 아연(II)착이온의 桓元에 대하여 압력에 따른 폴라로그래피적 파라미터의 依存性을 조사하였다. 水銀滴下電極, 고인수은전극 및 나선형 백금선을 각각 作業電極, 基準電極 및 補助電極으로 사용하였다. 압력이 1기압에서 1,500기압으로 증가함에 따라 금속착이온의 還元半波電位는 陰電位 쪽으로 이동하였으며, 擴散電流는 상당히 커졌다. 이러한 현상은 전해질용액의 물리적 성질 곧 密度, 粘性度, 誘電常數, 電氣傳導度 등이 압력이 증가함에 따라 커지기 때문이다. 압력을 증가시키면 log plot의 기울기 값이 커지므로 환원반응의 可逆性은 나빠지고 있다. 25$^{\circ}$C ~ 35$^{\circ}$C의 온도범위에서 측정한 확산전류의 溫度係數가 압력을 증가시켜도 2%정도이므로 高壓下에서 폴라로그래피적 환원반응은 擴散支配的이다. 또 실험압력 범위내에서 금속착이온의 확산전류와 농도 사이에는 線形關係가 성립하였다.

• Carbon letters
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• 제10권2호
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• pp.114-122
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• 2009

Crushed, depitted peach stones were impregnated activated with 50% $H_3PO_4$ followed by pyrolysis at $500^{\circ}C$. Two activated carbons were produced, one under its own evolved gases during pyrolysis, and the second conducted with air flow throughout the carbonization stage. Physicochemical properties were investigated by several procedures; carbon yield, ash content, elemental chemical analysis, TG/DTG and FTIR spectra. Porosity characteristics were determined by the conventional $N_2$ adsorption at 77 K, and data analyzed to get the major texture parameters of surface area and pore volume. Highly developed activated carbons were obtained, essentially microporous, with slight effect of air on the porous structure. Oxygen was observed to be markedly incorporated in the carbon matrix during the air treatment process. Cation exchange capacity towards Cu (II) and Cd (II) was tested in batch single ion experimental mode, which proved to be slow and a function of carbon dose, time and initial ion concentration. Copper was up taken more favorably than cadmium, under same conditions, and adsorption of both cations was remarkably enhanced as a consequence of the air treatment procedure. Sequestration of the metal ions was explained on basis of the combined effect of the oxygen functional groups and the phosphorous-containing compounds; both contributing to the total surface acidity character.