본 연구에서는 LiCI-KCl/Cd계의 전해제련 공정을 대상으로 악티늄 및 희토류족 원소들의 전해이동을 모텔링하고 해석하였다. 이 공정에서 용융염 전해질과 액체 카드륨 음극간의 확산 경계층 계면에서 확산제한 전기화학반웅 및 물질수지를 고려한 단순화된 통적모댐을 수립하였다 제안된 모델링 접근방법은 옴극에서 일어나는 금속엽의 반쪽 전 지 환원반용에 기초릎 둔 모델이다 이 모탤올 사용하여 정전류 전해공정에서 주어진 인가전류 조건을 만족하는 시간까지의 전해 이 동과 연계된 농도거동, 각 원소의 패러데이 전류 그리고 시간 함수의 전기화학 전위를 예측하는 가놓성을 보여주었다 선택된 5성분 원소(U , Pu, Am, La, Nd) 계의 결과를 예비 모사하여 전산모댈이 전기화학적 특성을 이해하고 개선된 전해 제련로를 개발하기 위한 정보를 제공할 수 있는가를 평가하였다.
The effects of Cd2+ ions on the Chl a fluorescence of 5 hydrophytes (e.g. Lemna, Salvinia, Ricciocarp, Nymph, Typha plants) were investigated in order to select Cd2+-sensitive plant species and to get informations on physiological responses of plants to Cd2+ stress. Lemna plants were most sensitive to cadmium stress, while Nymph plants were tolerant. However, in all Cd2+-treated plants, Fv/Fm, the maximum photochemical efficiency of PSⅡ, decreased in proportion to the increase of Cd2+ concentration and treatment time. The Chl a fluorescence transient O-J-I-P was also considerably affected by Cd2+ ions; the fluorescence yield decreased considerably in steps J, I and P in Cd2+ 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 Cd2+ concentration, while N, Mo and Kn increased. The structural parameters, Φpo, Φpo/(1-Φpo), Plabs, SFlabs, Kp and RC/ABS, also decreased according to the increase of Cd2+ 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.
본 연구는 화단국을 이용하여 미적 가치를 제공할 수 있는 관상식물의 중금속에 대한 생육 양상 및 중금속 축적 능력을 확인함으로써 오염지의 경광조성 및 환경친화적인 중금속 정화방법인 식물복원법(phytoremediation)의 가능성을 규명을 위해 화단국인 도입품종인 ‘Branivory'과 국내 육성 품종인 ‘금방울’과 ‘화이트 미리’를 공시하여 토양 내에 Cd를 처리하여 생육량과 생리적 특성을 조사하였다. 공시 3품종의 신초장은 Cd처리구에 비해 대조구에서 다소 높았고, 특히 화이트 미리’는 216mm의 가장 높은 신초장을 보였고, Cd 처리구에서는 대조 품종인 ‘Branivory'에 비해 국내 육성종인 ‘화이트 미리’는 처리구의 16주에서 높은 196mm의 신초장을 보였다. 지상부 생체중과 건물중에서도 ‘화이트 미리’는 대조구에 비해 낮은 것으로 보였으나, 다른 품종에 비해 16주의 Cd 처리구에서는 높은 23.7g의 생육반응을 나타내는 특성을 보였다. 또한 식물체 내의 생리물질의 변화에 있어서는 수용성 단백질 함량은 Cd 처리구에서는 전체적으로 대조구에서 그 함량이 증가하였으나, 수용성 탄수화물에서는 시간별 품종간 차이를 보였는데 ‘Branivory’와 ‘금방울’에서는 8주차에서 가장 높은 경향을 보였다. 엽록소 함량은‘금방울’ 품종에 있어서는 8주 대조구에서 4.81mg/g으로 가장 현저하였다. 한편 Cd 처리구에서 생육량과 생리적 양상에서 다소 저해를 보였지만 축적량이 증가하는 경향을 보였고, '금방울’에서 8주의 2.88ppm, 16주의 7.04ppm 이었고, ‘Branivory'는 1.55ppm(8주), 2.56ppm(16주)으로, ‘화이트 미리’에서는 0.31ppm(8주), 0.88ppm(16주) 순으로 품종간 차이가 현저하였다. 따라서 국내 육성품종과 도입품종의 간의 비교에서 토양오염지에서 국내 육성품종에 있어 생육상에서는 화이트 미리’가 우수한 생육반응을, 중금속 축적에서는 '금방울’에서 우수함을 나타냄으로써 경관조성이 가능한 phytoremediator로서의 가능성이 있을 것이라 생각된다. 그러나 또한 그 효과를 극대화시키기 위해 보다 많은 품종의 비교실험이 필요할 것으로 생각되며, 인산, 소석회, 토양개량제 등의 첨가를 통한 토양내 bioavailability를 높이고 활착과 보다 많은 건물생산량을 높일 수 있는 연구가 뒤따라야 할 것으로 생각된다.
본 연구는 환경친화적인 중금속 정화방법인 식물복원법(phytoremediation)의 적합성 규명을 위해 경관적 가치를 제공할 수 있는 조경수인 개나리(Forsythia koreana Nakai), 명자나무(Chaenomeles speciosa Koidz) 와 쥐똥나무(Ligustrum obtusifolium )Sieb. et Zucc.의 Cd처리에 따른 생육량과 생리적 특성을 조사하였고, 식물체내의 중금속 축적량을 확인하여 중금속 오염지에 대한 식물복원 개량대책을 위한 가능성을 알아보고자 실시하였다. 생장반응에 있어 Cd의 영향은 생장량의 감소현상은 뚜렷하였으며, 쥐똥나무 경우 6월 7일경에 무처리구는 신초장 60.10cm를 보였으나, Cd 처리구는 11.50cm로 생육이 감소하였다. 한편 명자나무에서는 Cd 처리구에서 가장 생육이 극히 부진하여 Cd에 내성이 약한 것으로 나타났다. 또한 Cd 처리에 따른 생리적 특성에 있어 엽록소 함량은 개나리에 있어 Cd 처리구에서 3.36 mg/g으로 4.85 mg/g인 대조구에 비해 현저하게 감소하였고, 쥐똥나무에서도 4.17mg/g에서 2.57mg/g으로 현저한 감소하는 경향을 보였다. 또한 TSC 함량의 변화는 엽록소의 변화에 매우 유사한 경향을 보였다. Cd 처리에 따른 전 질소 함량의 변화는 쥐똥나무의 Cd 처리구에서 가장 낮은 6.82를 보였다. 한편 soluble protein 함량에 있어서는 모두 Cd 처리구에서는 대조구와 큰 차이가 없었다. 한편 Cd에 대한 조사대상 식물들의 축적정도는 개나리에 있어 10.36ppm인 지하부의 Cd 중금속의 축적량은 2.37ppm인 지상부에 비해 4.3배 정도 많았고, 명자나무는 지상부 1.06ppm에 비해 지하부가 7.17ppm로 6.7배이며, 쥐똥나무는 지상부 함량이 3.23ppm인 반면에, 지하부가 5.12 ppm으로 1.5배로 높게 나타냄을 알 수 있다. 식물체의 지하부 축적량을 비교하면 개나리>명자나무> 쥐똥나무 순으로 볼 수 있으나, 지상부에서는 쥐똥나무>개나리>명자나무 순으로 중금속의 축적량이 가장 많았다.
This study was performed to examine the accumulated concentrations (conc.) of cadmium (Cd) in the organs of Arabidopsis thaliana grown in the soil with different conc. of Cd. The official standard conc. of Cd of pollutant exhaust notified by the Korean ministry of environment (0.1 mg/L) and ten times higher (1 mg/L) and fifty times higher (5 mg/L) conc. and no Cd in the soil as control were used for this investigation. The results showed that accumulated conc. of Cd in the stems of plant grown in the soil with different conc. (0.1, 1 and 5 mg/L) were increased 9%, 24% and 286% respectively, compared with normal plant stem. The accumulated conc. of Cd in the leafs of plant grown in the soil with official standard conc. and conc. ten times higher and conc. fifty times higher were increased 3%, 22% and 453%, respectively, compared with normal plant leaf. The accumulated conc. of Cd in the root of plant grown in the soil with 0.1 and 1 mg/L conc. of Cd were increased 6%, 19%, respectively, compared with normal plant root. However, it was observed about 84% of increased accumulation of the Cd in the root of plant, when highest (5 mg/L) conc. was used. The accumulated conc. of Cd in the different organs of Arabidopsis thaliana were increased according to increase of Cd conc. in the soil. When official standard conc. and ten times higher conc. of Cd were used, the accumulated conc. of Cd increased average 6%, 21%, respectively, compared with normal plant organ, and the accumulated conc. of Cd between leaf, stem and root were not significant. However, the accumulated conc. of Cd in the plant organs grown in the conc. fifty times higher were increased about 285%, compared with normal plant. In addition, the accumulated conc. of Cd in different organs of Arabidopsis thaliana exhibited wide differences between organs, that is, stem was increased 118% than root, leaf was increased 256%, 64% than root and stem, respectively. These results show that accumulated conc. of Cd in Arabidopsis thaliana with highest (5 mg/L) conc. of Cd in soil, were much higher in the leaf than the stem or root in proportion to the conc. of Cd contaminated within the soil.
말차, 오룡차, 홍차 및 보이차로 제조한 음료가 Cd에 중독된 SD계 흰쥐의 해독에 미치는 영향을 조사하였다. 관능검사 결과 일반 물 추출물에 비하여 색상, 향, 맛에 대한 기호도가 현저하게 향상되었으며, 종합적 기호도는 오룡차 음료가 4.18점, 홍차음료가 4.14점으로 말차음료나 보이차 음료의 점에 비하여 높았다. SD계 흰쥐를 정상군 (NC), Cd 대조군(Cd-Co), Cd투여 말차음료 15% 급여군 (Cd-Gt), Cd투여 오룡차음료 1
This experiment was carried out to investigate the effects of cadmium on the growth of Arabidopsis thaliana when they were treated with different concentrations of cadmium. The growth of stem was stimulated in the concentrations up to fifty times higher than the official standard concentration of cadmium of pollutant exhaust notified by the Ministry of Environment, but it decreased in the concentration one hundred fifty times or more higher in proportion to the degree of concentration. The growth of root was similar to that of stem, except that the decrease was gradual in the concentration fifty times or more higher. The growth of leaf was almost the same as that of stem, that is, it was stimulated the increase of leaf surface area in the concentration fifty times higher, but decreased in the concentration one hundred fifty times or more higher in proportion to the degree of concentration. The fresh weights of the plants were increased in accord with the degree of growth of the stem and leaf. Concentration of cadmium accumulated in the plants was increased in proportion to the concentration of cadmium. These results show that the growth of plants was stimulated in the soil polluted by cadmium up to fifty times higher than the official standard concentration, but it was decreased in proportion to the degree of concentration in the plants grown in the presence of cadmium more than one hundred fifty times
Heavy metals like Mercury and Cadmium cause various kinds of toxicities in the organs of Liver and Kidney. To observe the results of toxicity in the liver, kidney, and serum when the rats were injected subcutaneously with HgCl2 and CdCl2 and sacrificed after 24 hours and 72 hours from the last injection, we measured variation of lipidperoxide values in rat liver homogenate, variation of aspartate aminotransferase and alanine aminotransferase in rat serum. Variation of lipidperoxide values in rat kidney homogenate and variation of BUN in rat serum.
It was found that Mercury and Cadmium administered subcutaneously to the skin in the air could cause the damages of liver and kidney.
The biosorption and desorption of Cd were carried out using brown marine algae, known as the good biosorbent of heavy metals. The content of alginate bound to light metals could be changed by the physical and the chemical pretreatment of Sargassum fluitans biomass. The Cd uptake was independent of the alginate content. In case of protonated biomass, Cd uptake was the lowest because the alginic acid of biomass was dissolved to cadmium solution during the biosorption. The maximum Cd uptake of Sargassum biomass was ranged from 79㎎/g to 139㎎/g. In case of raw biomass, the higher the alginate content of biomass, the higher was the Cd uptake. 100% of Cd and light metals sorbed in the biomass were eluted at 0.1N HCl(pH 1.1). However, the elution efficiency in CaCl2 and Ca(NO3)2 solution was varied by the concentration, the solid to liquid ratio and the pH of calcium solution. The distribution coefficient between Cd and protons in the desorption solution at pH ranged from 1.6 to 2.9 was observed on the constant stoichometric coefficient(1.3).
To investigate the cadmium (Cd) toxicity on the testis, male rats were treated with 1, 2, 4 and 8 mg/kg of Cd by IP. According to histochemical studies, Cd-treated testis tissue showed death of spermatozoa, death of Sertoli cells, death of all the spermatogenic cells, and finally disappearance of basal lamina of seminiferous tubules with increasing doses, and showed decreased ground substances and Leydig cells, increased inflammatory cells and fibroblasts, and fibroblasts, and finally disappearance of ground substances and all the cells except fibroblasts within interstitial tissues with increasing doses. According to biochemical studies, two kinds of proteins, 25 and 45 kDa, were dramatically disappeared from the total protein of rat testis treated with Cd comparing to normal testis. The result of electrophoresis of total protein suggests that actin (45 kDa), presumed on its mmolecular weight and amount, in the testis-cells is the primary target of Cd poisoning. Although its exact mechanism is not clear, the disappearance of two proteins when testis is exposed to Cd should give some clues to understnad the mechanism of necrosis of testis tissue crumbling by heavy metal pollutant such as Cd.