• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.109-112
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• 2000

Long chain fatty acids (LCFA) are potential inhibitors of bacteria involved in anaerobic digestion because of their surface activity. Precipitation of long-chain fatty acids with iron can improve the anaerobic degradation due to their precipitation and reducing surface properties. Degradation of stearic acid was improved in the presence of iron (II). The methane production was increased 1.6 times as compared to control. Iron-containing soil was applied for degradation of vegetable oil as model case. The methane production was increased 1.5 times as compared to control. Yield of methane production was 0.09 and 0.06L/g COD in experiment and control respectively. Optimum COD/Fe ratio was found 20 mg/mg. Iron (II) can be produced in the treatment system from iron (III) hydroxide or iron containing minerals.

• Environmental Engineering Research
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• v.18 no.4
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• pp.267-276
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• 2013

This study presents a comparison of different protocols for the synthesis of iron-loaded zeolites, and the results of their application, as well as that of zeolite-A (Z-A), to the removal of ammonium and phosphate from aqueous media. Zeolites prepared by three methods were evaluated: iron-incorporated zeolites (IIZ), iron-exchanged zeolites (IEZ), and iron-calcined zeolites (ICZ). The optimal iron content for preparing of IIZ, as determined via scanning electron microscopy and X-ray photoelectron spectroscopy analyses, expressed as molar ratio of $SiO_2:Al_2O_3:Fe$, was below 0.05. Ammonia removal revealed that the iron-loaded zeolites have a higher removal capacity than that of Z-A due, not only to ion-exchange phenomena, but also via adsorption. Greater phosphate removal was achieved with IEZ than with ICZ; additionally, no sludge production was observed in this heterogeneous reaction, even though the coagulation process is generally accompanied by the production of a large amount of undesired chemical sludge. This study demonstrates that the developed synthetic iron-loaded zeolites can be applied as a heterogeneous nutrient-removal materials with no sludge production.

• Journal of Conservation Science
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• v.35 no.4
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• pp.317-329
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• 2019

Slag was collected from the iron-producing furnace site in Saengsoegol, Baegun mountain, where iron was manufactured by a righteous army against Japan in the Gwangyang region; then, the iron-manufacturing technique of the early modern period was investigated through scientific analysis. In the microstructure analysis results of the selected samples, iron bloom was mainly observed together with magnetite and fayalite. In the component analysis results of the compounds, it was confirmed that the furnace was built by using gangue of alkali feldspar or plagioclase series, and the ironmaking work was performed at a high temperature of at least 1050℃, because mullite was identified together with cristobalite and hercynite. Based on the chemical composition, it was speculated that low-grade iron ores were used as raw materials, and it seemed that the yield was low, because the total Fe content of the smelting slag samples was 37.72-49.93%. It was difficult to confirm whether a slag former was used, and it seemed that materials easily obtained nearby were used when the furnace was built, without considering the corrosion resistance. It appeared that the ironmaking work was performed at the Gwangyang Saengsoegol iron-producing furnace based on the direct ironmaking method in an environment that could escape the vigilance of the Japanese Empire to produce weapons that would be used for the resistance against Japan. It seemed that there was neither an advanced ironware production system nor a mass production system, and small-scale works were performed in short periods of time.

• Journal of Microbiology
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• v.44 no.5
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• pp.537-547
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• 2006

This study was designed to determine whether or not Vibrio vulnificus metalloprotease VvpE can promote iron uptake via the proteolytic cleavage of human hemoglobin. We found that V. vulnificus utilized hemoglobin as an iron source more efficiently via the vulnibactin-mediated iron-uptake system than via the HupA-mediated iron-uptake system and, of the proteases produced by V. vulnificus, VvpE was found to be the only protease capable of destroying hemoglobin. However, VvpE expression, on both the transcriptional and protein levels, was suppressed in iron-limited media. However, vvpE transcription, but not extracellular VvpE production, was reactivated by the addition of hemoglobin or inorganic iron into iron-limited media. Moreover, vvpE transcription began only in the late growth phase when V. vulnificus had already consumed most of the iron for growth. In addition, neither vvpE mutation nor in trans vvpE complementation affected the ability of V. vulnificus to acquire iron or to grow in iron-limited media or in cirrhotic ascites containing hemoglobin. Hemoglobin added into iron-limited media was not destroyed, but gradually formed an insoluble aggregate during culture; this aggregation of hemoglobin occurred regardless of vvpE mutation or complementation. These results indicate that VvpE is not required for efficient iron uptake from hemoglobin. On the contrary, hemoglobin or iron is required for efficient vvpE transcription. In addition, a discrepancy exists between vvpE transcription and extracellular VvpE production in iron-limited media containing inorganic iron or hemoglobin, which suggests that additional unknown posttranscriptional events may be involved in the extracellular production of VvpE.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.1
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• pp.103-106
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• 2008

A broiler experiment was conducted to compare the effects of supplementary iron sources and levels on the iron content of broiler meat. Two hundred and fifty hatched Ross broiler chickens were randomly assigned to 5 dietary treatments. Each treatment had 5 replicates of 10 birds (5 males and 5 females). Birds were housed in raised floor batteries and fed traditional broiler diets ad libitum for 5 weeks. Dietary treatments were as follows: Control, Fe-Met 100 (100 ppm iron as Fe-methionine), Fe-Met 200, $FeSO_4$ 100 (100 ppm iron as $FeSO_4{\cdot}7H_2O$) and $FeSO_4\;200$. There were no significant differences among treatments in parameters related to production performance. Liver contained approximately 10 times more iron than the leg muscle which contained approximately 3 times more iron than either breast muscle or wing muscle. Significant differences in iron content in the broiler meat were observed. In the breast meat, Fe-Met treatments were significantly (p<0.05) higher than other treatments in iron content. In the leg meat, Fe-Met treatments and $FeSO_4\;200$ treatment were significantly higher than the control in iron content. In the wing muscle, Fe-Met 200 treatment was significantly higher than other treatments in iron content. Iron content in the liver was significantly influenced by source and supplementation level of iron. Fe-Met treatments were higher than $FeSO_4$ treatments and 200 ppm treatments were higher than 100 ppm treatments in iron content in the liver. It is concluded that iron-methionine chelate is more efficient than iron sulfate and 200 ppm iron supplementation as Fe-Met is recommended for maximum iron enrichment in broiler meat.

• Journal of Microbiology
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• v.43 no.1
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• pp.54-61
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• 2005

In this study, we attempted to determine the effects of iron-availability and the activity of the bacterial iron-uptake system (IUS) on the growth of Staphylococcus aureus in human peritoneal dialysate (HPD) solution. A streptonigrin-resistant S. aureus (SRSA) strain, isolated from S. aureus ATCC 6538, exhibited defective siderophore production, thereby resulting in ineffective uptake of iron from low iron-saturated transferrin. The growth of both strains was stimulated in HPD solution supplemented with FeCl_3 and holotransferrin, but growth was inhibited in HPD solution which had been supplemented with apotransferrin and dipyridyl. The SRSA strain grew less robustly than did its parental strain in both iron-supplemented HPD solution and regular HPD solution. These results indicate that iron-availability and siderophore-mediated IUS activity in particular, the ability to produce siderophores and thus capture iron from low iron-saturated transferrin play critical roles in the growth of S. aureus in HPD solution. Our results also indicated that the possibility of using iron chelators as therapeutic or preventive agents warrants further evaluation.

• The Korean Journal of Archival Studies
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• no.24
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• pp.215-274
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• 2010

Iron-making industries of the country, regardless of age has been the focus. This makes the iron production technology and production techniques that result in increased economic activity and because of the central charge. Therefore, the social development of ancient iron-making technology is based on phase-sensitive. Modern steel making up the monopoly of the country's target under the strict control of production, distribution was. It is essential to produce iron weapons was a threat is because you can keep the throne in the hands of the forces that can cause side effects when I went was to block. This study created a rail Cholbi(iron monument) and the regional distribution pattern of the production, construction background, looked on. Cholbi(iron monument) for the production and recording "the Annals of the Joseon Dynasty" often appear in history books and many academic interests, but was off target. Compared to a stone monument that was not generally as well as the Japanese colonial period and over the course of modernization destroyed, damaged a lot of cases the cause may be found in front. Cholbi(iron monument), except for the gravestones of the Joseon Dynasty monument erected in honor of virtue, as an example of content that dominated a packman business, founding of the school and confirmed that a few were built as a special purpose. Cholbi(iron monument) compared to the production technology or the cost of the monument's difficulty in financing follows. Therefore Cholbi(iron monument) the establishment of the Joseon Dynasty through the background of the economic situation and the local government can look. And iron technology began complaining about the object of history, economic conditions, with the change of season has been a change in people's consciousness tells you. Important data of ancient history as an epigraph that has been as important, the Middle Ages to modern times ranging from newly born to the time Cholbi(iron monument) in the development of the country's documentary subject to change should have been brought. Based on these discussions changes the identity of the hero monument and production inspector, review of production through the Joseon Dynasty period Cholbi (iron monument) contemplated the significance is reflected in production.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.134-149
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• 2013

The Sudang-ri Site in Geumsan is considered the historic site where Baekje dominated the inland traffic route to Gaya through Geumsan and Jinan in the 5th Century. This study identified the production techniques of iron by conducting an analysis of metallographical microstructure of the artifacts such as an iron sword and an iron sickle that were excavated in Sudang-ri Site, Geumsan, one of the regions ruled by Baekje, and tried to figure out the characteristics and the technical systems of Baekje's ironmaking around the 5th Century by comparing them with other iron artifacts produced around the same time. The analysis showed that various production techniques were applied to the artifacts excavated in Sudang-ri Site, Geumsan. Depending on the production techniques, they can be divided largely into three methods: the simple shape-forging method, the steel manufacture method after forging, and the steel manufacture & heat-treatment method after forging. The iron sickle from the stone chamber tomb No. 1, which was produced only through forging, is mostly composed of soft ferrite at both edges of the blade and at the rear making the use of the weapon impractical. From this fact, it is presumed that they were produced as burial objects or ceremonial accessories for the person buried. The iron axe from the outer stone coffin tomb No. 1 and the iron swords and sickle from the outer stone coffin tomb No. 12, which were produced through the steel manufacture method after forging such as carburizing, did not go through the heat treatment such as quenching, but applied different production processes to each part. Therefore, it is deemed that they were produced as daily tools for cultivation rather than burial objects or ceremonial accessories. The production techniques following the forging process - carburizing and heat treatment - can be found on the iron swords from the outer stone coffin tomb No. 5 and the outer stone coffin tomb No. 12. The sturdy structure of the blade part and the durable structure of the rear processed with heat are deemed to have been produced as weaponry and used by the person buried. Based on the analysis of the iron artifacts excavated from Sudang-ri Site in Geumsan, the characteristics of iron production techniques were investigated by comparing them with the artifacts from Yongwon-ri Site in Cheonan, Bongseon-ri Site in Seocheon, and Bujang-ri Site in Seosan that were made around the same time as the cluster of Baekje tombs examined by the metallographical microstructure analysis of this study. For the iron artifacts analyzed here, the changes in the techniques were investigated using the iron swords common in all of the tombs. In the case of the iron swords, it was identified the heat treatment technique called tempering was applied from the 4th Century.

• KSBB Journal
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• v.14 no.2
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• pp.241-247
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• 1999

Experimental studies were carried out to optimize the culture conditions of Corynebacterium diphtheriae for the production of diphtheria toxin. A new media which does not contain any meat digest products was selected. The main ingredient of new medium was enzymatic digests of casein known as NZ-Case. In fermenter experiments, the toxin production was increased with the increase of cell growth. The optimum initial pH of media, air flow rate and agitation speed were 7.0, 0.22, vvm and 400 rpm, respectively. The contents of iron and calcium-phosphate precipitate were important for maximal cell growth and toxin production. The optimum concentration of iron was 0.3 mg/L and calcium-phosphate precipitate could serve in gradual supply of iron to maintain the optimal culture condition which is required for enhanced yield of toxin production. In potency test, the potency of toxoid from fermentor culture was higher than that from static culture. When diphtheria toxin is produced by fermentor culture, it is possible to produce higher levels of toxin and better toxoid quality in terms of safety, yield, productivity and immunity.

• Journal of architectural history
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• v.25 no.5
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• pp.27-40
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• 2016

The purpose of this study was to comprehend the procurement system of iron materials and the production process of ironwork in royal tombs constructions in the later Joseon period. For this purpose, sixteen Sanneung-uigwes were analyzed. The following conclusions have been reached through the study. First, it was procuring five types of iron materials in constructions of royal tombs. Sincheol had been supplied up to the mid-18th century. On the other hand, the amount of jeongcheol was increased rapidly. Because of the procurement system of initial tools was changed from bokjeong(a kind of tribute) to self-production in the Noyaso. Second, the government stockpiles were utilized as much as possible than bokjeong to manage the limited construction period and sudden construction start. Third, before moving the site of tombs, the melting furnace was installed in the Gungisi(armament factory). The amount of the melting furnace was increased from 5 to 8 since producing the initial tools in the Noyaso. Fourth, six kinds of master artisans were worked in the field of producing ironwork. Metal worker was assigned to one person per melting furnace. Fifth, the quality of final iron materials was controlled by use. Since the 19th century, it had been produced enhanced ironwork.