• Title/Summary/Keyword: PH

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The physicochemical characteristics of silk-tofu added with medicinal herb powder preserved in kochujang and deonjang (Tofujang) (약초첨가 비단두부의 장담금에 따른 이화학적 특성)

  • Lim Ji-Suk;Cho Eun-Ja
    • Korean journal of food and cookery science
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    • v.21 no.4 s.88
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    • pp.447-458
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    • 2005
  • The effect of medicinal herb Powder addition on the Physicochemical characteristics of tofujang preserved in kochujang and deonjang was investigated. The moisture contents of tofujang decreased rapidly till 4 weeks of storage, after which they showed a slight tendency to increase. The PH values of cochujang tofujang and deonjang tofujangs showed a tendency to decrease, but then showed a tendency to increase a little. The saltiness of tofujang increased rapidly till 2 weeks of storage, and then increased gently. The chromaticity of L and a values decreased, and that of b value significantly increased, during a storage. The total microbial counts of kochujang tofujang decreased till 4 weeks of storage, and then increased a little (103 CFU/ml). The total microbial counts of deonjang tofujang were decreased during storage. The total free amino acids content of silk-tofu was extremely small $(0.16\~0.92 mg/ml)$, but after 4 weekn of preservation, that of tofujang preserved in kochujang and deonjang increased to 10mg/ml and 40mg/ml, respectively In the kochujang tofujang, the textural characteristics of hardness, gumminess and chewiness increased rapidly at initial preservation and then showed a tendency to decrease significantly. The springiness and cohesiveness values showed no specific tendency. In the deonjang toking, the textural characteristics of hardness and gumminess increased till 2 weeks of preservation, and then tended to decrease. The springiness, chewiness and cohesiveness value had a tendency to decrease significantly with preservation. In the sensory evaluation, color, aftertaste and overall acceptability of mok-k tofujang showed significantly high score, but there was no significance in nutty taste, sweet, salty and hot. Color, savory, sweet and overall acceptability of mok-d and con-d tofujang were high, and the saltiness and aftertaste of sin-d tofujang got high score.

Degradation of the Herbicide, TOK(2,4-dichloro-4'-nitro diphenyl ether) in Soil (제초제(除草劑) TOK의 토양중(土壤中) 분해(分解))

  • Lee, Jae-Koo;Kim, Ki-Cheol;Kim, Chang-Han
    • Applied Biological Chemistry
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    • v.23 no.2
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    • pp.131-139
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    • 1980
  • TOK (2,4-Dichlolo-4'-nitrodiphenyl ether) was applied to two Korean soils possessing different physico-chemical properties at a certain concentration and incubated for a certain time under flooded conditions. The metabolites and the soil microorganisms involved in the degradation of TOK are studied. Chong Ju and Chung Ju soils treated with TOK at a concentration of 500 ppm and incubated for two, four, and six months at $30^{\circ}C$ yielded 4-chloro-4'-amino diphenyl ether, 2, 4-dichloro-4'-amino diphenyl ether(amino-TOK), N-[4'-(4-chloro-phenoxy)] phenyl acetamide, and N-[4'-(4-chloro-phenoxy)] phenyl formamide as the major metabolites. TOK underwent the reduction of nitrogroup to amino group, dechlorination, acetylation, and formylation. No cleavage at the ether linkage was recognized. TOK was more readily degraded in Chung Ju soil which is characterized by the higher pH (PH 6.43), clay loam in textural class, and the higher cation exchange capacity. The toxicity of TOK as a possible environmental contaminant is expected to be considerably reduced as a result of the above degradation Twelve strains of soil bacteria were isolated from the TOK-treated Chong Ju and Chung Ju soils. As a result of the incubation of TOK in pure cultures of the isolates, T-1-1 strain isolated from Chong Ju soil had almost no degradability, whereas T-2-3 strain turned out to be the most potent. The degradation of TOK by the isolates constituted mostly the reduction of the nitro group to amino group. The citrate buffer extract of Chung Ju soil reduced TOK more readily to amino-TOK than that of Chong Ju soil.

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Forest Vegetation and Soil Environment on Mt. Paekun (백운산의 삼림식생과 토양환경)

  • 이호준;배병호;정흥락;전영문;홍문표
    • Korean Journal of Environmental Biology
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    • v.17 no.1
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    • pp.35-50
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    • 1999
  • The relationship between floristic composition and soil environmental conditions was investigated in the forest vegetation of Mt. Paekun. The forest vegetation unit of Mt. Paekun was divided into six plant communities by Zurich-Montpellier method, such as Quercus mongelica community (Typical subcommunity, Rhododendron schlippenbaohii subcommunity), Q. variabilis community, Fraxinus rhynchophylla community, Pinus densiflora community, Larix Eeptolepis community and Pinus koraiensis community. Q. mongolica community group was distributed at the altitude over 500 meter, Q. variabilis and P. densiflora communities appeared on the southwestern slope at the altitudes of 600 ~ 700 m and 290 ~ 700 m. However, L. leptolepis and P. koraiensis plantation were distributed at lower altitude, on hillside or around homestead. The DBH class distribution of dominant species in each community showed that Q. mongolica had 10.9 individuals/a at 6~10 cm class, Q. variabilis 2.5 individuals/a at 11~15 cm class, P. densiflora 1.8 individuals/a at 26~30 cm class, F. rhynchophylla 3.3 individuals/a at 2~5 cm class, and L. leptolepis 5.9 individuals/a at 11~ 15 cm class. Q. mongolica and Q. variabilis communities showed a stable bell-shaped pattern of distribution. The contents of organic matters and soil water, and cation exchange capacity of the soil increased, and the pH decreased as the altitude gets higher increased altitude at the each communities. The contents of the soil water and organic matters of the forest soil collected in Q. mongolica community were in the 17.81% to 51.20% and 5.51% to 14.90%, respectively. These tendency is similar to the contents of N, P and K, but those of Ca, Mg, and CEC was lower than in other communities. Cation exchange capacity was suspected to be correlated to the pH. The hypothetical successional sere of the forest vegetation of Mt. Paekun is as follows: Pinus densiflora community longrightarrowQ. variabilis community longrightarrowQ. mongolica community.

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Le Lien de Causalit$\acute{e}$ et la Prescription Extinctive en Mati$\acute{e}$re de Responsabilit$\acute{e}$ M$\acute{e}$dicale en Droit Français (프랑스법상 의사책임분야(醫事責任分野)에서의 인과관계와 소멸시효론에 관한 소고)

  • Park, Soo-Gon
    • The Korean Society of Law and Medicine
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    • v.15 no.2
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    • pp.367-397
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    • 2014
  • Dans le contentieux m$\acute{e}$dical, il est difficile de prouver l'existence d'un lien de causalit$\acute{e}$ entre la faute m$\acute{e}$dicale et les pr$\acute{e}$judices subis par la victime. R$\acute{e}$partir bien de façon raisonnable la charge de la preuve du lien causal est alors une des questions pr$\acute{e}$occup$\acute{e}$es par la doctrine cor$\acute{e}$enne. La Cour supr$\hat{e}$me cor$\acute{e}$enne semble toutefois facilliter l'indemnisation des victimes dans les cas o$\grave{u}$ la responsabilit$\acute{e}$ du m$\acute{e}$decin a ${\acute{e}}t{\acute{e}}$ mise en cause, et cela en admettant des fois une solution op$\acute{e}$rant un renversement de la charge de la preuve du lien causal. Une telle attitude a ${\acute{e}}t{\acute{e}}$ m$\hat{e}$me affirm$\acute{e}$e dans un arr$\hat{e}$t rendu r$\acute{e}$cemment en cas de dommage caus$\acute{e}$ par le fait du produit de sant$\acute{e}$, notamment pour le cas de contamination virale par voie de transfusion. La Cour a $\acute{e}$galement reconnu que l'action se pr$\acute{e}$scrit $\grave{a}$ partir du moment de la consolidation du pr$\acute{e}$judice. Aux termes de cette $\acute{e}$tude, on pourra constater que le juge français reconna$\hat{i}$t aussi l'assouplissement de la charge de la preuve du lien de causalit$\acute{e}$ en mati$\acute{e}$re d'action m$\acute{e}$dicale. Il faudra toutefois souligner que le ph$\acute{e}$nom$\acute{e}$ne ne soit pas g$\acute{e}$n$\acute{e}$ralis$\acute{e}$ en droit français, d'autant plus que la pr$\acute{e}$somption de l'existence de la causalit$\acute{e}$ en la mati$\grave{e}$re a $\acute{e}$t$\acute{e}$ admise de mani$\grave{e}$re restrictive par la l$\acute{e}$gislation sp$\acute{e}$cifique. Tel $\acute{e}$tait notamment le cas pour les accidents de la contamination par le virus du sida ou de l'h$\acute{e}$patite C survenus apr$\grave{e}$s la transfusion. En d$\acute{e}$finitive, on peut dire qu'en droit français, le principe est maintenu en cas de manquement $\grave{a}$ une obligation de r$\acute{e}$sultat n$\acute{e}$e du contrat m$\acute{e}$dical, tandis que la Cour de cassation admet parfois en mati$\grave{e}$re de droit commun de la responsabilit$\acute{e}$ contractuelle la pr$\acute{e}$somption de causalit$\acute{e}$ en cas d'inex$\acute{e}$cution des obligations de r$\acute{e}$sultat. En fait, la pr$\acute{e}$somption de causalit$\acute{e}$ dans le contentieux m$\acute{e}$dical pourra mener les m$\acute{e}$decins $\grave{a}$ se diriger vers les traitements d$\acute{e}$fensifs. Cette situation peut m$\hat{e}$me conduire $\grave{a}$ emp$\hat{e}$cher le d$\acute{e}$veloppement de la science m$\acute{e}$dicale, enfin $\grave{a}$ une situation d$\acute{e}$savantageuse aux patients. Il y a alors lieu de se m$\acute{e}$fier des int$\acute{e}$r$\hat{e}$ts d$\acute{e}$s$\acute{e}$quilibr$\acute{e}$s entre le m$\acute{e}$decin et le patient. De ce point de vue, on peut estimer que le droit français donne des suggestions aux juristes cor$\acute{e}$ens dans la recherche des solutions plus ad$\acute{e}$quates en ce qui concerne la charge de la preuve du lien causal en mati$\acute{e}$re de responsabilit$\acute{e}$ m$\acute{e}$dicale.

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Characterization of InAs Quantum Dots in InGaAsP Quantum Well Grown by MOCVD for 1.55 ${\mu}m$

  • Choe, Jang-Hui;Han, Won-Seok;Song, Jeong-Ho;Lee, Dong-Han
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.134-135
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    • 2011
  • 양자점은 전자와 양공을 3차원으로 속박 시키므로 기존의 bulk나 양자우물보다 양자점을 이용한 레이저 다이오드의 경우 낮은 문턱 전류, 높은 미분이득 및 온도 안전성의 장점이 있을 거라 기대되고 있다. 그러나, 양자점은 낮은 areal coverage 때문에 높은 속박효율을 얻지 못하고 있다. 이러한 양자점의 문제점을 해결하기 위해 양자점을 양자우물 안에 성장시켜 운반자들의 포획을 향상시키는 방법들이 연구되고 있다. 양자우물 안에 양자점을 넣으면 양자우물이 운반자들의 포획을 증가 시키고, 열적 방출도 억제하여 온도 안정성이 향상 되는 것으로 알려져 있다. 광통신 대역의 1.3 ${\mu}m$ 경우, GaAs계를 이용하여 InAs 양자점을 strained InGaAs 박막을 우물층으로 한 dot-in-a-well 구조의 연구는 몇몇 보고된 바 있다. 그러나 InP계를 사용하는 1.55 ${\mu}m$ 대역에서 dot-in-a-well구조의 연구는 아직 미미하다. 본 연구에서는 유기 금속 화학 증착법(metal organic chemical vapor deposition)을 이용하여 InP 기판 위에 InAs 양자점을 자발성장법으로 성장하였으며 dot-in-a-well 구조에서 우물층으로 1.35 ${\mu}m$ 파장의 $In_{0.69}Ga_{0.31}As_{0.67}P_{0.33}$ (1.35Q)를, 장벽층으로는 1.1 ${\mu}m$ 파장의 $In_{0.85}Ga_{0.15}As_{0.32}P_{0.68}$(1.1Q)를 사용하였다. 양자우물층과 장벽층은 모두 InP 기판과 격자가 일치하는 조건으로 성장하였다. III족 원료로는 trimethylindium (TMI)와 trimethylgalium (TMGa)을 사용하였으며 V족 원료 가스로는 $PH_3$ 100%, $AsH_3$ 100%를, carrier gas로는 $H_2$를 사용하였다. InP buffer층의 성장 온도는 640$^{\circ}C$이며 양자점 성장 온도는 520$^{\circ}C$이다. 양자점 형성은 원자력간 현미경(Atomic force microscopy)를 이용하여 확인하였으며, 박막의 결정성은 쌍결정 회절분석(Double crystal x-ray deffractometry)를 이용하여 확인하였다. 확인된 성장 조건을 이용하여 양자점 시료를 성장하였으며 광여기분광법(Photoluminescence)을 이용하여 광특성을 분석하였다. Fig. 1은 dot in a barrier 와 dot-in-a-well 시료의 성장구조이다. Fig. 1(a)는 일반적인 dot-in-a-barrier 구조로 InP buffer층을 성장하고 1.1Q를 100 nm 성장한 후 양자점을 성장하였다. 그 후 1.1Q 100 nm와 InP 100 nm로 capping하였다. Fig. 1(b)는 dot-in-a-well 구조로 InP buffer층을 성장하고 1.1Q를 100 nm 성장 후 1.35Q 우물층을 4 nm 성장하였다. 그 위에 InAs 양자점을 성장하였다. 그 후에 1.35Q 우물층을 4 nm 성장하고 1.1Q 100 nm와 InP 100 nm로 capping하였다. Fig. 2는 dot-in-a-barrier 시료와 dot-in-a-well 시료의 상온 PL data이다. Dot-in-a-barrier 시료의 PL 파장은 1544 nm이며 반치폭은 79.70 meV이다. Dot-in-a-well 시료의 파장은 1546 nm이며 반치폭은 70.80 meV이다. 두 시료의 PL 파장 변화는 없으며, 반치폭은 dot-in-a-well 시료가 8.9 meV 감소하였다. Dot-in-a-well 시료의 PL peak 강도는 57% 증가하였으며 적분강도(integration intensity)는 45%가 증가하였다. PL 데이터에서 높은 에너지의 반치폭 변화는 없으며 낮은 에너지의 반치폭은 8 meV 감소하였다. 적분강도 증가에서 dot-in-a-well 구조가 dot-in-a-barrier 구조보다 전자-양공의 재결합이 증가한다는 것을 알 수 있으며, 반치폭 변화로부터 특히 높은 에너지를 갖는 작은 양자점에서의 재결합이 증가 된 것을 알 수 있다. 이는 양자우물이 장벽보다 전자-양공의 구속력을 증가시키기 때문에 양자점에 전자와 양공의 공급을 증가시키기 때문이다. 따라서 낮은 에너지를 가지는 양자점을 모두 채우고 높은 에너지를 가지는 양자점까지 채우게 되므로, 높은 에너지를 가지는 양자점에서의 전자-양공 재결합이 증가되었기 때문이다. 뿐만 아니라 파장 변화 없이 PL peak 강도와 적분강도가 증가하고 낮은 에너지 쪽의 반치폭이 감소한 것으로부터 에너지가 낮은 양자점보다는 에너지가 높은 양자점에서의 전자-양공 재결합율이 급증하였음을 알 수 있다. 우리는 이와 같은 연구에서 InP계를 이용해 1.55 ${\mu}m$에서도 dot in a well구조를 성장 하여 더 좋은 특성을 낼 수 있으며 앞으로 많은 연구가 필요할 것이라 생각한다.

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The spore densities of Arbuscular mycorrhizal fungi related to the Soils collected from Polluted and Unpolluted areas (오염지역과 비오염지역의 토양에 관한 Arbuscular mycorrhizal fungi의 포자밀도)

  • Shim, Jae-Ouk;Lee, Sang-Sun;Chang, Young-Soo
    • The Korean Journal of Mycology
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    • v.24 no.1 s.76
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    • pp.56-66
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    • 1996
  • Ecological variations of Arbuscular mycorrhizal (AM) fungi were determined from the soils collected from different sites of the polluted and unpolluted areas related to the soil pollutions. Average 24.5 spores $(per\;20g)^{-1}$ soil of AM fungal spore were counted from the 32 sites of soils collected from On-san (polluted), whereas average 4.1 spores $(per\;20g)^{-1}$ soil from the 18 sites of those from Mt. Kwanak (polluted); Average 23.6 spores $(per\;20g)^{-1}$ soil of AM fungal spore were also counted from the 30 sites of soils collected from Chung-mu (unpolluted), whereas average 15.8 spores $(per\;20g)^{-1}$ soil from the 14 sites of those from Mt. Chungwang (unpolluted).The spores of AM fungi were the species of Glomus, Gigaspora, Acaulospora and Scutellospora. Among the above four genera, the species of Glomus were observed to be more abundant than the other genera in the soils collected from On-san, Chung-mu and Mt. Chungwang whereas the species of Gigaspora in those from Mt. Kwan-ak. The parameters of soils measured showed some variations between the polluted and unpolluted areas; 12.9 to 16.4% in the soil moisture, 5.6 to 8.3% in the organic matter and 4.3 to 5.7 at soil pH (polluted to unpolluted areas, respectively). The soils collected, thereby, appeared to be more strongly acidic and also lower in the contents of soil moisture or organic matter at the polluted area than unpolluted area. Based on the ecological criteria, the species richness or species diversity had significant differences (p<0.05) between polluted and unpolluted area. The spore density of genus Glomus or Gigaspora was significantly different (p<0.05) among the soils of three different plant vegetations (conifer plants, broad leaf plants, and grass plants). Also, there were significant differences (p<0.05) in the species evenness or species diversity among the soils referring to three different plant vegetations. There was a direct relationship $(r^2=0.38)$ between soil moisture and organic matter measured from 94 soil samples. Since there was a direct relationship $(r^2=0.22)$ between organic matter and total spores, it seems to be likely to presume that mycorrhizal spores can be increased in proportion to enhanced organic matters in soils. The species richness or species diversity was inclined to increase in proportion to enhanced soil pH and total spores in soils.

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Material Balance and Properties of Compost during Composting of Household Food Wastes Blended with Waste Newspapers (신문지 첨가에 의한 음식쓰레기 퇴비화 과정 중 물질수지 및 퇴비의 성분)

  • Han, Jong-Phil;Park, Ju-Won;Seo, Jeoung-Yoon
    • Korean Journal of Environmental Agriculture
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    • v.19 no.1
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    • pp.51-57
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    • 2000
  • Waste newspapers was used as an amendment to adjust the moisture of household food wastes for composting. The mixture of household food wastes and waste newspapers was composted in an especially designed small home composter, where the early fed composting materials were discharged early. The temperature inside composting materials was influenced very much by that of outside, because the composter was not insulated. Accordingly, the higher the outside temperature was, the higher the decomposition rate was. The temperature inside composting materials did not reach to optimum, because the amount of composting materials added in the composter everyday was too little, and it caused too high water content of discharged compost after 15 weeks. Therefore, it was required that the composter must be insulated to maintain the higher temperature. The inorganic compounds$(K_2O,\;CaO,\;MgO,\;P_2O_5)$ and heavy metals(Zn, Cu, Cr, Cd, Hg, As) were accumulated obviously in produced compost, when dry recycled compost was reused as the amendment for adjusting the moisture.

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Effect of reducing components in spice oils on the nitrite role in model meat systems (육가공 모델 시스템에서 아질산염의 역할에 미치는 향신료 환원성분의 영향)

  • Kim, In-Ho;Lee, Seong-Ki;Kim, Ze-Uook
    • Applied Biological Chemistry
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    • v.33 no.2
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    • pp.147-153
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    • 1990
  • To investigate the effect of spice oils on the nitrite role in processed meat products, eight spice oils, ascorbic acid, and nitrite at different combinations were added to marcerated pork, and cooked at $70^{\circ}C$ lot 30min or $121^{\circ}C$ for 15min. The cooked sample were stored at $5.5^{\circ}C$ for 12days and pH, residual nitrite, redness, TBA value, and antimicrobial activity were analyzed. pH of the uncooked samples were stable at $5.6{\sim}5.8$ except in samples with nitrite alone, anise, ascorbic acid, and black pepper in which pH increased to $6.7{\sim}7.8$ after 5 days of storage. The pH of the cooked samples were stable at $5.9{\sim}6.1$ during the storage. Residual nitrite decreased rapidly on the first day of storage in each model. Residual nitrite decreased rapidly on the first day of storage in each model. The nitrite reducing effect was greatest in sample with ascorbic acid, followed by clove eugenol and thyme, but was small with peppermint. The redness of the sample was increased with ascorbic acid, colve, eugenol, thyme, anise, black pepper, coriander and rosemary except peppermint, specially samples with ascorbic acid, clove and eugenol were prominent. The TBA values of the samples with cloves, eugenol and ascorbic acid, stored after nine days, were $4{\sim}6.5$ lower than that of nitrite added sample and indicated strong antioxidant activity. The antimicrobial activity determined by inhibition zone, was strong in samples with clove, eugenol, peppermint, thyme, coriander, black pepper, rosemary and anise had antimicrobial activity to the Penicillium sp. Specially with clove, eugenol, peppermint and thyme, while all the samples showed $7{\sim}10mm$ inhibition zone to the Salmonella sp. The above results suggest that addition of eugenol, clove and thyme oil to the processed meat may increased the antioxidant, antimicrobial activity, and redness of the product so that could provide a way of reducing nitrite addition into meat products.

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Studies on Partition and Extraction Equilibria of Metal-Dithiocarbamate Complexes(II). Metal Complexes of Ammonium Pyrrolidine Dithiocarbamate (Dithiocarbamate 금속착물의 분배 및 추출평형(제2보). Ammonium Pyrrolidine Dithiocarbamate의 금속착물)

  • Lee, Jong-Sun;Choi, Jong-Moon;Choi, Hee-Seon;Kim, Young-Sang
    • Analytical Science and Technology
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    • v.8 no.3
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    • pp.321-334
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    • 1995
  • Basic studies for the effective extraction of ammonium pyrrolidine dithiocarbamate(APDC) complexes of Co(II), Ni(II) and Cu(II) into a solvent have been performed. The maximum distribution ratio was appeared (log D=1.3543) at pH 2.0 and the partition coefficient was 2.489 in the extraction of $4{\times}10^{-5}M$ APDC itself into chloroform. From the UV/visible spectra of metal-chelates in aqueous and organic solutions, the pH to form stable 1:2 metal-ligand complexes were Co(II):5.0, Ni(II):8.0 and Cu(II):8.0, respectively and only 1 minute was enough to be partitioned into the chloroform. Besides, the partition and extraction equilibria of the complexes were investigated by back-extracting $10.0{\mu}g/ml$ metal-chelates from the solvent into an aqueous solution beacuse of their slight solubilities in the aqueous solution. The distribution coefficients and extractabilities were as follows : at pH 6.5~8.5 of the aqueous solution, log D=2.834 : E(%)=99.9% for $Co(PDC)_2$, at pH 11, log D=5.699 E%=100 for $Ni( PDC)_2$, and at pH 6.0, log D=2.025 : E(%)=99.1% for $Cu(PDC)_2$. And the extraction and formation constants were log $K_{ex}=9.671$ : log ${\beta}_2=6.938$ for $Co(PDC)_2$, log $K_{ex}=9.646$ : log ${\beta}_2=7.071$ for $Ni( PDC)_2$, and log $K_{ex}=9.074$ : log ${\beta}_2=7.049$ for $Cu(PDC)_2$, respectively. From these results, an optimum extraction procedure can be constructed for the separative concentration of trace metallic ions, and the quantitative determination of them in advanced materials and environmental samples will be expected without any influence of sample matrixes.

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Effect of NMDA Receptor Antagonist on Local Cerebral Glucose Metabolic Rate in Focal Cerebral Ischemia (국소뇌허혈에서 NMDA 수용체 길항제가 국소 뇌포도당 대사율에 미치는 영향)

  • Kim, Sang-Eun;Hong, Seung-Bong;Yoon, Byung-Woo;Bae, Sang-Kyun;Choi, Chang-Woon;Lee, Dong-Soo;Chung, June-Key;Roh, Jae-Kyu;Lee, Myung-Chul;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.29 no.3
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    • pp.294-306
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    • 1995
  • There has recently been increasing interest in the use of NMDA receptor antagonists as potential neuroprotective agents for the treatment of ischemic stroke. To evaluate the neuroprotective effect of the selective non-competitive NMDA receptor antagonist MK-801 in focal cerebral ischemia, local cerebral glucose utilization (ICGU) was examined in 15 neuroanatomically discrete regions of the conscious rat brain using the 2-deoxy-D[$^{14}C$] glucose quantitative autoradiographic technique 24 hr after left middle cerebral artery occlusion (MCAO). Animals received MK-801 (5 mg/kg i.v.) or saline vehicle before (20-30 min) or after (30 min) MCAO. Both pretreatment and posttreatment of MK-801 increased occluded/non-occluded ICGU ratio in 7 and 5 of the 15 regions measured, respectively (most notably in cortical structures). Following MK-801 pretreatment, there was evidence of widespread increases in ICGU not only in the non-occluded hemisphere (12 of the 15 areas studied) but also in the occluded hemisphere (13 of the 15 areas studied), while MK-801 postreatment did not significantly increase ICGU both in the normal and occluded hemispheres. These data indicate that MK-801 has a neuroprotective effect in focal cerebral ischemia and demonstrate that MK-801 provides widespread alterations of glucose utilization in conscious animals.

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