• Korean Journal of Plant Resources
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• v.22 no.6
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• pp.540-545
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• 2009

Aloe (Aloe vera L.), cucumber (Cucumis sativus L. var. tuberculatus Gabaj.) and sponge.gourd (Luffa cylindrica L.) are well utilized in Asian countries as traditional medicines and cosmetics, or foods. And we carried out an experiment to see if there are some specific ratios among trace metals on the plants. Though the metal concentrations varied significantly depending on the sampling periods, aloe gel is high in iron (Fe) and calcium (Ca). Cucumber fruit juice is also high in iron (Fe) and potassium (K). Sponge.gourd sap contains a high amount of zinc (Zn) and calcium (Ca). The uses of the previous 3 plant parts are considered to have some relations to their different ratios and of their trace metals.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.444-449
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• 2016

Industrial by-products generated by integrated iron and steel manufacture cause environmental pollution. The by-products contain not only iron element but also harmful substances. Therefore, in view of to waste recycling and environmental preservation, production of sponge iron using the by-product is considered an effective recycling method. In this study, reduction efficiency of pellets from blast furnace dust was measured. Metallization was found to be increased, as $C/Fe_{total}$ ratio and reaction time were increased. The pellets were formed into a globular shape, and calcined for 60 minutes at $1100^{\circ}C$ in an electric furnace. Phase changes were analyzed using an X-ray diffractometer. Microstructures of the pellets were observed by a scanning electron microscope.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1187-1188
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• 2006

This paper compares the effect of using different types of iron powders for the preparation of $Sm_2Fe_{17}$ by calciothermic reduction-diffusion (CRD). Three types of iron powder were used: carbonyl, sponge and water atomized. The results show that, when immediately nitrogenated after the CRD process, $Sm_2Fe_{17}$ prepared from sponge and water atomized iron powders yield $Sm_2Fe_{17}N_3$-magnets with a high degree of texture. However, after a suitable treatment with hydrogen followed by nitrogenation, $Sm_2Fe_{17}$-powders made from Carbonyl iron produce magnets with the best quality regarding coercivity, remanence and degree of texture.

• Journal of Conservation Science
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• v.18 s.18
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• pp.33-50
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• 2006

Around Yeongsan river basin, there are Yeongkwang Gundong, Muan Inpyeong Tombs, Muu Gusan-ri Tombs and Hampyeong Guksan remain from which a lot of iron artifacts were excavated. Among them, 6 iron artifacts were chosen, and their microstructures were analyzed. As a result, Iron artifacts were produced sponge iron by the low temperature reduction process and a part of microstructure have the possibility that steel made by decarburizing. And also, by tempering the parts which need high strength, the iron artifacts had high strength and by distributing the weakness of the tempered structure to the nearby untempered parts, their breaking was prevented and they had the durability. These skills were used then. Especially these skills were found to be used in the 2nd century by high skilled people because an iron axe excavated at Yeongkwang Gundong of 2nd century by the historical record showed that the skill was used. Also microstructures were found to show the possibility that the iron technology was inherited to the late 5th century. When producing iron artifacts made of sponge iron containing small amount of carbon, that was made by the production process repeating molding, carburizing, heat treatment and hammering.

• Journal of Conservation Science
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• v.17 s.17
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• pp.57-64
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• 2005

In the course of examining the micro structure of Iron chisel and Iron arrowhead, a relics of the 16th or 17th of Chosun Dynasty unearthed at near Gangsun-tower, Chengpyeong temple. Collected un-eroded samples from the relics were looked into the metallic structure through optical metallography. Non-metallic inclusions were-analysed by SEM and EDS. The micro structure examination and SEM-SDS analysis revealed that Iron chisel and Iron arrowhead had been produced from the sponge iron close to pure iron made by low temperature reducing in a solid and then the surface carbon content was increased by carburizing treatment. It was also found that Iron chisel had been hardened through the repetitive processes of quench hardening and heat treatment, after increasing carbon content to a certain level. Up to now, there have been a number of studies in the domestic academia which were studied mainly on the structure of metallic relics in the period of the Three Kingdoms or before. Although this research was limited in type and number of the relics, it turned out to be interesting in that it revealed the 16th or 17th century way of processing iron, even in fragments. It is thought to be fruitful that iron had been made even in the Chosun Dynasty from the sponge iron.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.43-54
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• 2004

In the course of examining the metallic structure of Iron chisel and Iron arrowhead, a relics of the 16th or 17th of Chosun Dynasty unearthed at near Gangsun-tower, Chengpyeong temple, we collected un-eroded samples from the relics and looked into the metallic structure through mounting, grinding and polishing, and etching, while analyzing non-metallic inclusion via SEM and EDS. The research metallic structure and SEM-SDS analysis, found that Iron chisel and Iron arrowhead had been produced from sponge iron close to pure Iron made by solid low heat reducing and then increased in rate of carbon by carburizing, It also found that Iron chisel had been hardened through the repetitive process of quench hardening and heat treatment, after being increased in amount of carbon to a certain level. Up to now, there have been a number of studies in the domestic academia which were made primarily of the structure of metallic relics of three countries the period or tile era before that. Although this research was limited in type and number of the relics, it turned out to be Interesting in that it revealed the 16thor 17th century way of processing iron, even in fragments. It is thought to be fruitful that we found iron had been made even in the Chosun Dynasty from sponge iron. It is recommended that researches be made on the relics later to be excavated and originally made in $Kory\breve{o}$ or Chosun Dynasty, because they are important in history of metal technology.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.10
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• pp.1021-1028
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• 2004

Developed friction snubbers changes the shock or vibration into a heat energy by mechanical friction. Snubber is divided into friction snubbers and hydraulic snubbers according to the operation types. However, hydraulic snubber has a lot of problems caused by temperature, humidity, radioactivity, and viscosity of hydraulic fluid. In these respects, to solve these problems, not only do friction snubber supplement lacks of hydraulic snubber but has also simpler structure than hydraulic snubber. In this paper, friction snubber used sponge iron by friction material is experimentally compared with general friction snubber In this results, the experiment verifies friction function and produce the manufacture condition for the effective friction snubber development.

• Conservation and Restoration of Cultural Heritage
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• v.1 no.1
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• pp.9-22
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• 2012

The most widely excavated iron artifacts used as weapons or farm tools from central southern regions of Korea were subjects of non-metallic inclusion analysis through metallographic examination, microhardness measurement, and scanning electron microscopy with energy dispersive X-ray spectroscopy. Through metallographic interpretation and study of the analyzed results, the steel manufacturing and iron smelting using heat processing in the iron artifacts excavated from the central southern region of the ancient Korean peninsula was studied, and the analysis of the non-metallic inclusions mixed within the metallic structures was interpreted as the ternary phase diagram of the oxide to infer the type of iron ores for the iron products and the temperature of the furnace used to smelt them. Most of the ancient forged iron artifacts showed $Al_2O_3/SiO_2$ with high $SiO_2$ contents and relatively low $Al_2O_3$ contents for iron ore, indicating t hat for $Al_2O_3$ below 5%, it is presumed that magnetic iron ores were reduced to bloom iron (sponge iron) with direct-reduction process for production. The temperature for extraction of wustite for $Al_2O_3$ below 1% was found to be $1,020{\sim}1,050^{\circ}C$. Considering the oxide ternary constitutional diagram of glassy inclusions, the steel-manufacturing temperature was presumed to have been near $1,150{\sim}1,280^{\circ}C$ in most cases, and minimum melting temperature of casting iron part excavated in Daeseong-ri. Gyeonggi was near $1,400^{\circ}C$, and it is thought that hypoeutectic cast iron of about 2.3% carbon was casted and fragility of cast iron was improved by decarburizing in solid state.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.67-69
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• 1996

Some physical properties and inorganic components of sap from sponge-gourd(Luffa cylindrica L.) were investigated for their changes affected as collection time. Huter valves, pH, turbidity and viscosity of the sap were not different. pH value was indicated at slightly alkalinity and decreased by culturing period. Potassium, calcium and magnesium were major inorganic components of the sap and podium, zinc and iron were minor components. Copper was not detected in open culturing and also manganes way not detected in all samples.

• Environmental Engineering Research
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• v.24 no.1
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• pp.173-179
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• 2019

Prussian blue (PB) is known to be an effective material for radioactive cesium adsorption, but its nano-range size make it difficult to be applied for contaminated water remediation. In this study, a simple and versatile approach to immobilize PB in the supporting matrix via surface functionalization was investigated. The commercially available poly vinyl alcohol (PVA) sponge was functionalized by acrylic acid (AA) to change its major functional group from hydroxyl to carboxylic, which provides a stronger ionic bond with PB. The amount of AA added was optimized by evaluating the weight change rate and iron(III) ion adsorption test. The FTIR results revealed the surface functional group changing to a carboxyl group. The surface functionalization enhanced the attachment of PB, which minimized the leaching out of PB. The $Cs^+$ adsorption capacity significantly increased due to surface functionalization from 1.762 to 5.675 mg/g. These findings showed the excellent potential of the PB-PAA-PVA sponge as a cesium adsorbent as well as a versatile approach for various supporting materials containing the hydroxyl functional group.