• Title/Summary/Keyword: Ferric oxide

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Removal Nitrogen and Phosphorus from Wastewater using Natural Zeolite and Iron Oxide (천연 Zeolite와 산화철을 이용한 폐수 중 질소 및 인의 처리)

  • Weon, Seung-Yeon;Lee, Sang-Ill
    • Journal of Korean Society on Water Environment
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    • v.20 no.2
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    • pp.104-109
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    • 2004
  • Removal of nutrients from domestic sewage or industrial wastewater is needed to protect surface waters from eutrophication. This research was carried out to remove the nitrogen (N) and phosphorus (P) from the wastewater using the iron oxide obtained from the steel industry and the natural zeolite, respectively. This research was conducted in both batch and continuous systems. The removal efficiency of the nutrients was evaluated in the batch system using the varying concentrations of zeolite and iron oxide added. The removal efficiency of N was 60% at the 8g of zeolite added. In the same condition, the removal efficiencies of N were 76% and 82% at 12g and 16g of zeolite added, respectively. Removal efficiency of P was 80% as 8g of iron oxide was added. The removal efficiency of P was correspondingly increased as the concentration of iron oxide was increased. Continuous column system was also used to evaluate the removal efficiency of N and P by the addition of zeolite and ferric oxide, respectively. Removal efficiencies of N were compared in the mixed packing, two stage, and four stage columns, respectively. The removal efficiencies (80%) of N in the separate packed columns (two and four stages) were higher than the mixed packing column (400%) after 90 hr. Whereas, the removal efficiencies of P were similar to each other in the three columns.

Effect of FeOOH on Burn Rate for AP Propellant (AP계 추진제에서 황색산화철의 연소촉매 효과)

  • Yim, Yoo-Jin;Kim, Jun-Hyung;Yoo, Ji-Chang
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.05a
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    • pp.390-393
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    • 2010
  • The thermal decomposition rate of ammonium perchlorate with 3% of yellow iron oxide, FeOOH was found to be much faster than with red iron oxide, $Fe_2O_3$. By applying yellow and red iron oxide as a burning rate modifier to HTPB/AP propellant, burning rate of the HTPB/AP propellant with yellow iron oxide was shown to be 10 ~ 25% faster than with red iron oxide. There was no special difference in viscosity and hardness buildup of yellow and red oxide added HTPB/AP formulations.

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Solid Propellants for Propulsion System Including A Yellow Iron Oxide (황색산화철을 포함하는 혼합형 추진제의 특성에 관한 연구)

  • Park, Sungjun;Choi, Sunghan;Won, Jongung;Park, Jungho;Park, Euiyong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.498-503
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    • 2017
  • There is no unusual difference in the initial viscosity of the propellant applied with yellow iron oxide and red iron oxide. In addition, the thermal decomposition rate of the material added with yellow iron oxide is faster than that of the addition of red iron oxide. Especially, it was confirmed that the pressure exponent was 18% lower at high temperature and high pressure. The initial viscosity was lowest at 71% of large particle/small particle ratio

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Bioconversion of nitrogen oxides and reduction of ferric ions by probiotic lactic acid bacteria (프로바이오틱스 유산균에 의한 질소 산화물 전환 및 철 이온 환원활성)

  • Kim, Selim;Hong, Jungil
    • Korean Journal of Food Science and Technology
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    • v.53 no.6
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    • pp.785-791
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    • 2021
  • Many lactic acid bacteria (LAB) have probiotic properties that exert various health benefits. In this study, the reduction potential of nitrogen oxide compounds and ferric ions by six LAB, including Lactobacillus kimchicus, L. lactis, L. casei, L. plantarum, L. rhamnosus GG, and Leuconostoc mesenteroides were evaluated. The L. kimchicus strain produced a substantial amount of nitrite reduced from nitrate added to the media, whereas the other five LAB strains did not. L. kimchicus also showed the most potent reducing activity of ferric to ferrous ions. However, the reduction potential of the autoclaved L. kimchicus was little pronounced. The scavenging activities of viable LAB or their cell lysates against different radicals were not consistent with the potency of the LAB's reducing ability. The present results indicate that L. kimchicus has a strong reduction potential for nitrogen oxides in viable status, and that this ability can be used as a probiotic property for various health benefits.

Studies on the Phenolic Compound Content and Antioxidant Efficacy of Rubus idaeus (Raspberry) Cultivar 'Willamette' Fruit Extract Using n-Hexane and Ethyl Acetate (n-Hexane 및 Ethyl Acetate를 이용한 Willamette 품종 라즈베리추출물의 페놀 화합물 함량 및 항산화 효능 연구)

  • Park, Kyu Kun;Yoon, Year Pill
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.46 no.4
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    • pp.329-337
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    • 2020
  • In this study, Rubus idaeus (Raspberry) cultivar 'Willamette' fruit extract(RIFE) was prepared from the freeze-dried raspberry powder, n-hexane and ethyl acetate, and then the phenolic compound content, ferric reducing ability, and radical scavenging ability were measured. The raspberry cultivar 'willamette', 'polka', and 'polana' compound fruit extract did not show cytotoxicity up to the concentration of 10%. As a result of conducting an experiment at the concentration, it was confirmed that the total phenolic compound content was 375.3 ppm, and the total flavonoid content was 43.46 ppm, and the ferric reducing ability by ferric reducing antioxidant power (FRAP) reagent was equivalent to FeSO4 0.532 mM. It was confirmed that 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability was 94.5 ± 0.7%, and the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging ability was 99.4 ± 2.82%, and the nitric oxide (NO) radical scavenging activity was 88.5 ± 0.4%. When compared with the L-ascorbic acid 'standard' solution, DPPH radical scavenging ability was between 25 - 50 ppm / ABTS radical scavenging ability was close to 100 ppm / NO radical scavenging ability was more than 1,000 ppm. These results suggest that the raspberry cultivar 'willamette' fruit extract could be applied as an effective cosmetic material with antioxidant activity.

ABTS+ Radical, Hydroxy Radical (OH), Nitric Oxide (NO), and Ferric Ion Reducing Antioxidant Power (FRAP) Effects of Ethanol Extracts from Four Seaweed Species for Noodles (국수에 대한 4종 해조류 에탄올 추출물에 의한 ABTS+, OH 라디칼, NO 라디칼, 철 이온 환원력)

  • Cho, Kyung-Soon
    • Journal of Life Science
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    • v.27 no.10
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    • pp.1121-1129
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    • 2017
  • The authors evaluated the scavenging activities of ABTS+ radical, hydroxy radical (OH), nitric oxide (NO), and ferric ion reducing antioxidant power (FRAP) from ethanol extracts of four edible alga, Enteromorpha linza, Porphyra tenera, Sargassum fusiforme, and Undaria pinnatifida. ABTS+ scavenging activity was analyzed according to the method of Brand-Williams et al. ABTS+ scavenging activity of S. fusiforme was evaluated to 61.8% at 8.0 mg/ml. ABTS+ scavenging activity of P. tenera was evaluated to 35.7% at 8.0 mg/ml. P. tenera and U. pinnatifida showed similar inhibitions of ABTS+ scavenging activity. According to the results of the OH assay in seaweed, inhibitory activities were in the order of S. fusiforme > P. tenera > U. pinnatifida > E. linza. The results showed scavenging activity for NO in the following order of potency: S. fusiforme > P. tenera > U. pinnatifida > E. linza with concentration values of 8.0 mg/ml. The NO scavenging activities of dough, which was instant noodles mixed with S. fusiforme and 3.5% salt, were 27.2% at 8.0 mg/ml. After boiling for 5 minutes, FRAP scavenging activity of instant noodles mixed with extracts of U. pinnatifida was evaluated to 31.5% at 8.0 mg/ml. S. fusiforme showed the highest inhibition activity of ABTS+, OH, NO, and FRAP among the four algae. Thus, these findings provide evidence that P. tenera, U. Pinnatifida, S. fusiforme, and E. linza extracts could become sources of natural antioxidants.

Characteristics of the TCE removal in FeO/Fe(II) System (FeO/Fe(II) 시스템에서 TCE의 제거 특성)

  • Sung, Dong Jun;Lee, Yun Mo;Choi, Won Ho;Park, Joo yang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.1B
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    • pp.149-152
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    • 2008
  • The reaction between iron oxide and ferrous iron is known to be the adsorption of ferrous iron onto the oxide surfaces that produces Fe(II)-Fe(III) (hydr)oxides and ferrous oxide oxidized to ferric ion which is the reducing agent of the target compounds. In our investigations on DS/S using ferrous modified steel slag, the results did not follow the trends. FeO and Fe(II), the major component of steel slag, were used to investigate the degradation of TCE. Degradation did not take place for the first and suddenly degraded after awhile. Degradation of TCE in this system was unexpected because Fe(II)-Fe(III) (hydr)oxides could not be produced in absence of ferric oxide. In this study, the characteristics of FeO/Fe(II) system as a reducing agent were observed through the degradation of TCE, measuring byproducts of TCE and the concentration of Fe(II) and Fe(III). Adsorption of ferrous ion on FeO was observed and the generation of byproducts of TCE showed the degradation of TCE by reduction in the system is obvious. However it did not correspond with the typical reducing mechanisms. Future research on this system needs to be continued to find out whether new species are generated or any unknown mineral oxides are produced in the system that acted in the degradation of TCE.

Dual positional substrate specificity of rice allene oxide synthase-1: insight into mechanism of inhibition by type II ligand imidazole

  • Yoeun, Sereyvath;Rakwal, Randeep;Han, Oksoo
    • BMB Reports
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    • v.46 no.3
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    • pp.151-156
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    • 2013
  • Phylogenetic and amino acid sequence analysis indicated that rice allene oxide synthase-1 (OsAOS1) is CYP74, and is clearly distinct from CYP74B, C and D subfamilies. Regio- and stereo-chemical analysis revealed the dual substrate specificity of OsAOS1 for (cis,trans)-configurational isomers of 13(S)- and 9(S)-hydroperoxyoctadecadienoic acid. GC-MS analysis showed that OsAOS1 converts 13(S)- and 9(S)-hydroperoxyoctadecadi(tri)enoic acid into their corresponding allene oxide. UV-Visible spectral analysis of native OsAOS1 revealed a Soret maximum at 393 nm, which shifted to 424 nm with several clean isobestic points upon binding of OsAOS1 to imidazole. The spectral shift induced by imidazole correlated with inhibition of OsAOS1 activity, implying that imidazole may coordinate to ferric heme iron, triggering a heme-iron transition from high spin state to low spin state. The implications and significance of a putative type II ligand-induced spin state transition in OsAOS1 are discussed.

Fabrication of Transition Metal doped Sapphire Single Crystal by High Temperature and Pressure Acceleration Method

  • Park, Eui-Seok;Jung, Choong-Ho;Kim, Moo-Kyung;Kim, Hyung-Tae;Kim, Yoo-Taek;Hong, Jung-Yoo
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1998.09a
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    • pp.97-102
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    • 1998
  • Transition metal Cr3+ and Fe3+ ion was diffused in white sapphire {0001}, {1010} crystal plane which were grown by the Verneuil method. It enhanced and changed the physical, electrical and optical properties of sapphires. After mixing the metallic oxide and metal powder, it were used for diffusion. Metallic oxide was synthesized by precipitation method and it's composition was mainly alumina which doped with chromium or ferric oxide. In case using metallic oxide, the dopping was slowly progressed and it needed the longer duration time and higher temperature, relatively. Metallic powder was vapoured under 1x10-4 torr of vacuum pressure at 1900(iron metal) and 2050(chromium)℃, first step. Diffusion condition were kept by 6atm of N2 accelerating pressure at 2050∼2150℃. Each surface density of sapphire crystal are 0.225(c) and 0.1199atom/Å2(a). The color of the Cr-doped sapphires was changed to red. Dopping reaction was come out more deep in th plane of {1010} than {0001}. It was speculated that the planar density was one of the factors to determine diffusion effect.

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Qualitative comparison of chemical and green synthesized Fe3O4 nanoparticles

  • Gokila, V.;Perarasu, V.T.;Rufina, R. Delma Jones
    • Advances in nano research
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    • v.10 no.1
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    • pp.71-76
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    • 2021
  • Synthesis of nanoparticles using green technology using plants is gaining significant attention as it is an environmentally friendly substitute to conventional physical and chemical methods. The present study was focused on the chemical and green synthesis of Iron Oxide nanoparticles from ferric chloride. The green synthesis was achieved by utilizing the bio components of Hibiscus rosa-sinensis. The Fe3O4 nanoparticles with the size range of 87-400 nm were synthesized by wet chemical reduction technique which are unstable, prone to aggregation while in green synthesis the phytochemicals present in the leaf extract acts as the capping as well as the reducing agent thus the green synthesized iron (III) oxide nanoparticles were naturally stabilized, spherical shaped and are in the size range of 2-80 nm. The results of both the protocols are compared and presented briefly.