• Journal of Pharmaceutical Investigation
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• 제24권3호spc1호
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• pp.11-18
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• 1994

We have studied the iron uptake by the purified brush-border membrane vesicles (BBMVs) to determine the effect of fructose on the absorption of iron. BBMVs were prepared by the modified calcium precipitation method, The degree of purification was routinely assessed by the marker enzyme, alkaline phosphatase, and the functional integrity was tested by $D-[1-^3H]glucose$ uptake. The appearance of membrane vesicles was shown by transmission electron microscopy (TEM). The uptakes of complexes of labeled iron $[^{59}Fe]$ with fructose and ascorbate were measured with a rapid filtration technique, The uptake rate and pattern of the two iron-complexes, Fe(III)-fructose and Fe(III)-ascorbate, were also observed. A typical overshooting uptake of D-glucose was observed with peak value of $2{\sim}3$ times higher concentration than that at equilibrium. This result was similar to other studies with BBMVs. TEM showed that the size of BBMVs was uniform and we can hardly find any contaminants, Fe(III)-fructose has the higher value of $V_{max}$ and the lower value of Km than those of Fe(III)-ascorbate, respectively. It may be concluded that D-fructose is more effective in promoting the iron absorption than ascorbate.

• 한국환경과학회지
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• 제9권6호
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• pp.505-509
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• 2000

The purpose of this study was to evaluate the effects of $Ca(OH)_2$ and $CO_2$ additions on the corrosion of metal coupons(ductile iron, galvanized steel, copper and stainless steel). Corrosion rate and released metal ion concentration of ductile iron and galvanized steel decreased by adjusting alkalinity, calcium hardness and pH with $Ca(OH)_2$ & $CO_2$ additions on copper and stainless steel were less than those on ductile iron and galvanized steel. When ductile iron coupon was exposed to water treated with Ca(OH)$_2$&$CO_2$, additions, the main components of corrosion product formed on its surface were $CaCO_3$ and $Fe_2 O_3 or Fe_2 O_4$ which often reduce the corrosion rate by prohibiting oxygen transport to the metal surface.

• 한국주조공학회지
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• 제6권4호
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• pp.269-276
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• 1986

The effects of Se, $CaCO_3$ and CaO addition on the first stage graphization of malleable iron were evaluated. The results obtained in this work were as follows. 1. Many gas bubbles were found in the white cast iron under Se, $CaCO_3$ addition. 2. Nodular graphite were formed by annealing of the white cast iron with remained gas bubbles. 3. When specimens were annealed, bubbles provided the nucleation sites that were needed in graphite precipitation, so the nucleation rate of graphite was increased. 4. The remained gas bubbles and defects were more effective for the graphitization than metallic compounds.

• 전기화학회지
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• 제17권3호
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• pp.149-155
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• 2014

본 연구에서는 리튬 이차전지의 양극 재료인 $Li[Ni_{0.575}Co_{0.1}Mn_{0.325}]O_2$를 공침법(Co-precipitation)으로 전구체를 합성 하였고, 철(Fe)을 도핑 함으로써 양극 활물질을 합성하였다. 합성된 양극 활물질을 시차주사현미경 (SEM, Scanning electron microscope)과 X선-회절분석(XRD, X-ray diffraction)으로 분석하였다. X선-회절분석 결과 철(Fe)을 도핑 함으로써 a축과 c축이 증가하였고, $I_{(003)}/I_{(104)}$의 비가 증가하는 것과 $I_{(006)}+I_{(102)}/I_{(101)}$비가 작아지는 것을 통해 구조적 안정성이 증가하는 것을 확인했다. 전기화학적 특성 측정 결과 사이클 특성이 향상되었고, 임피던스 측정 결과 전하 이동 저항($R_{ct}$) 값이 낮아짐을 통해 전기화학적 분석 결과에서도 철(Fe)을 도핑 하였을 때 개선 된 특성을 나타내었다. 특히, 고온 조건에서 사이클 특성이 개선되는 것을 확인 하였는데, 이는 구조적 안정성이 사이클 특성에 기여하였기 때문이다.

• Journal of Plant Biology
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• 제1권1호
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• pp.27-37
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• 1958

Durlng various experiments and investigations with antigrowth virus, I studied especially the infective and antiinfective process of it in small animals, and have got following results: 1. The rabbits are easily infected with this virus, having following five stages; incubation period of 2 to 3 days, stage of fever for 2 to 4 day, transient anemic stage, transient fcteric stage and stage of lasting iron-precipitation in the spleen. 2. According to the appearance of icteruis, I have divided the rabbits into following three groups, the first gorup, weighting less than 1000g, died after appearance of icterus, the second group, weighting 1000 to 1500 g. recoy ered after appearance of icterus, and the third group, weighting more than 1500 g. recovered without the appearance of jaundice. 3. In hematological study, marked decrease in R. B. C. and Hb were recognized but various leucocytes except lymphocytes slightly increased. 4. In pathological study, the spleen exhibited marked swelling with abundent blood and indistinct border between trabeculae and pulps at the initial stage of icterus and notable atrophy at the end stage of it. There are few iron-cells in the spleen histologically at the initial stage, but they increased in number with granuar appearance at the end stage. In the first group of rabbits above mentionel, the iron-cells increase suddenly with the death of animal and show diffuse precipitation of iron. The liver and indey have defferent aspects in proportion to icterus. If icterus appears, they show markel changes with turbidity and necrosis, but without icterus they present only slight changes. 5. The neutralining antibody is easily proved in the immunized rabbits for about one year. 6. The passive immunity has the defense immunability until 10\ulcorner 7. Gunia pigs are easily infected with this virus and get the immunity. On fowls this virus can be kept in the blood for about ten days by various inoculating methods, and the fowls obtain the defensive ability by reinoculation, but are unable to succeed this ability from generation to generation. 8. when young swine are infected with this virus, their growth are disturbed and result in atrophied swine. It is therofor presumed that the etiology of the antigrowth of these atrophied swine is similar morphological and functional changes observed in the above rabbits.

• Environmental Engineering Research
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• 제16권4호
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• pp.187-203
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• 2011

Chlorophenols (CPs) are widely used industrial chemicals that have been identified as being toxic to both humans and the environment. Zero valent iron (ZVI) and iron based bimetallic systems have the potential to efficiently dechlorinate CPs. This paper reviews the research conducted in this area over the past decade, with emphasis on the processes and mechanisms for the removal of CPs, as well as the characterization and role of the iron oxides formed on the ZVI surface. The removal of dissolved CPs in iron-water systems occurs via dechlorination, sorption and co-precipitation. Although ZVI has been commonly used for the dechlorination of CPs, its long term reactivity is limited due to surface passivation over time. However, iron based bimetallic systems are an effective alternative for overcoming this limitation. Bimetallic systems prepared by physically mixing ZVI and the catalyst or through reductive deposition of a catalyst onto ZVI have been shown to display superior performance over unmodified ZVI. Nonetheless, the efficiency and rate of hydrodechlorination of CPs by bimetals depend on the type of metal combinations used, properties of the metals and characteristics of the target CP. The presence and formation of various iron oxides can affect the reactivities of ZVI and bimetals. Oxides, such as green rust and magnetite, facilitate the dechlorination of CPs by ZVI and bimetals, while oxide films, such as hematite, maghemite, lepidocrocite and goethite, passivate the iron surface and hinder the dechlorination reaction. Key environmental parameters, such as solution pH, presence of dissolved oxygen and dissolved co-contaminants, exert significant impacts on the rate and extent of CP dechlorination by ZVI and bimetals.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2004년도 International Symposium
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• pp.9-28
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• 2004

Concern about arsenic is increasing throughout the world, including areas of the United States. Elevated levels of arsenic above current drinking-water regulations in ground and surface water can be the result of purely natural phenomena, but often are due to anthropogenic activities, such as mining and agriculture. The current study correlates arsenic speciation in acid mine drainage and mining influenced water with the important water-chemistry properties Eh, pH, and iron(III) concentration. The results show that arsenic speciation is generally in equilibrium with iron chemistry in low pH AMD, which is often not the case in other natural-water matrices. High pH mine waters and groundwater do not 짐ways hold to the redox predictions as well as low pH AMD samples. The oxidation and precipitation of oxyhydroxides depletes iron from some systems, and this also affects arsenite and arsenate concentrations differently through sorption processes.

• 한국재료학회지
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• 제16권11호
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• pp.687-691
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• 2006

Synthesis of Iron oxides by air oxidation of $FeSO_4$ solutions in the presence of NaOH, Diethylenetriamine (DETA), Butylamine (BA) and influence of ultrasonic wave were investigated by XRD, SEM and particle size analyzer. As the DETA addition increased to 0.05 mol, $Fe_3O_4$ was formed with goethite($\alpha$- FeOOH) and $Fe_3O_4$ single phase was formed above 0.18mol of DETA. As the BA addition increased, the XRD peak intensity of (020) face of lepidocrocite($\gamma$-FeOOH) was developed until the formation of $Fe_3O_4$ and reduced the size of the iron oxide particles formed. Ultrasonic wave reduced the size of the iron oxide particles but gave little effects on the iron oxide particles synthesized by amine.

• 한국환경보건학회지
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• 제36권6호
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• pp.502-509
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• 2010

In this study, the (phosphorous removal) the characteristics of phosphorous removal due to (the iron compound precipitated) iron compound precipitation by iron electrolysis in (the anoxic. oxic process) anoxic and oxic processes (equipped with the) in an iron precipitation device were analyzed. During the device operation period, the average concentration of BOD, T-N, and T-P were 219.9 mg/l, 54.6 mg/l and 6.71 mg/l, respectively. The BOD/$COD_{Cr}$ ratio was 0.74, and the BOD/T-N and BOD/T-P ratios were 4.0 and 32.8, respectively. The removal rate of (the organic matters) organic matter (BOD and $COD_{Cr}$) was very high at 91.6% or higher, and that of nitrogen was 80.5%. The phosphorous concentration (of the final) in the treated water was 0.43 mg/l (0.05-0.74 mg/l) on average, and the removal efficiency was high at 90.8%. The soluble T-P concentrations in (an) the anoxic reactor, oxic reactor (II) and final treated water were 1.99 mg/l, 0.79 mg/l and 0.43 mg/l, respectively, which indicated that the phosphorous concentration in the treated water was very low. Regardless of the changes in the concentrations of (organic matters) organic matter, nitrogen and phosphorous in the influent, the quality of the treated water was relatively stable and high. The removal rate of T-P somewhat increased with the increase in the F/M ratio in the influent, and it also linearly increased in proportion to the T-P loading rate in the influent. In the treatment process used in this study, phosphorous was removed (using) by the precipitated iron oxide. Therefore, the consumption of organic (matters) matter for biological phosphorus removal was minimized and (most of the organic matters were) was mostly used as the organic carbon source for the denitrification in the anoxic reactor. This (can be an economic) treatment process (without the need for the supply of additional organic matters) is economic and does not require the supply of additional organic matter.

• Applied Biological Chemistry
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• 제44권4호
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• pp.219-223
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• 2001

Hemoglobin(Hgb)의 효소 가수분해액으로부터 고농도 heme-iron의 분리에 영향을 주는 기질의 농도, 가수분해도 (DH, degree of hydrolysis) 및 분리 pH의 효과 등을 조사하였으며, pilot scale에서 고농도 heme-iron을 생산하였다. 최적 반응조건(pH 10.0, $50^{\circ}C$, 5 hr)에서의 Esperase에 의한 Hgb의 DH는 $24{\sim}25%$였다. Hgb의 농도는 heme-iron의 분리에 영향을 미쳐서 Hgb의 농도가 2.5%, 5.0%, 10.0%로 증가할수록 heme-iron/peptide(heme-iron의 분리도)는 각각 47.4%, 35.6%, 21.8%로 감소하였으며, 이에 따라 농축율도 감소하였다. Hgb의 가수분해액으로부터 고농도 heme-iron의 분리에 효율적인 pH 영역은 DH에 따라 달라졌으며, DH가 6.3%의 경우는 pH $5.0{\sim}6$에서 heme-iron/peptide의 비가 8.92%, DH가 14.5%인 경우는 pH $4.0{\sim}6.0$에서 $12.1{\sim}19.5%$였으며, DH가 24.3%인 경우는 pH $3.0{\sim}5.0$에서 $34.7{\sim}36.4%$로 가수분해도가 높을수록 고농도 heme-iron의 분리시 최적 PH 범위가 산성 영역으로 이동되었으며, 이 영역의 pH에서 peptide의 용해도 증가로 분리도가 증가되었다. 가수분해액으로부터 분리된 heme-iron의 분자량은 약 1 kDa정도로 hematin과 유사한 분리패턴을 보였다. Pilot scale로 제조한 고농도 heme-iron 제품에서의 heme-iron 함량은 27.1%, heme-iron/peptide 비는 38.7%, 생산수율은 9.3%이었다.