• Korean Journal of Community Nutrition
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• v.3 no.2
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• pp.218-227
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• 1998

This study was performed to investigate the effects of dietary protein and calcium levels on iron and zinc balance in eight healthy Korean young women. The 20-day metabolic study consisted of a 2-day adaptation period followed by three 6-day experimental periods. Three experimental diets were the low protein-low calcium(LProLCa ; protein 44g, Ca 422mg), the high protein-low calcium(HProLCa ; 'protein 85g, Ca 365mg) and the high protein-high calcium (HProHCa ; protein 84g, Ca 727mg). Apparent absorption and balance of iron and zinc were significantly higher when subjects were fed high protein-low calcium diet than low protein-low calcium diet. The elevation of dietary calcium significantly depressed the apparent absorption of iron and zinc. The levels of serum iron and zinc were likely to be increased with a high protein diet, but the differences were not significant. There was a strong correlation(r=O.99) between the iron intake and serum iron concentration. Serum zinc concentration was not correlated with hair zinc. Study results revealed that the levels of dietary protein and calcium influence iron and zinc balance in Koreans. This study suggests that dietary recommendations for trace minerals, such as iron and zinc, should be carefully examined. In addition, there is a need to evaluate the bioavailability of milk or beverage products enriched with calcium and iron.

• Preventive Nutrition and Food Science
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• v.3 no.1
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• pp.1-9
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• 1998

Studies were performed to 1) investigate if ferric iron bound in complex with iron-solubilizing meat components is absorbable, 2) compare the relative iron-solubilizing capaicty of meats, and 3) investigate the physicochemical and compositional characteristics if meat meat has iron-solubilizing components . Iron-solubilizing components of beef were isolate from pH 2 HCL homogenates into dialysis bags(MWCO of 6-8K). Radiolabelled iron complexes were then generated using ferric iron and the isolated low-molecular-weight components(ILC) from undigested beef or ascrobate. The bioavailabilities of radioiron in these complexes or as ferric iron were measured as radioiron absorption into the blood one hour after injection into ligated duodenal lops of rats. Iron absorptions were ferrous -ascorbate complexes(18.8$\pm$2.2%)> ferric-ILC complexes(4.9$\pm$0.6%)>ferric iron (23.2$\pm$0.3%)(p<0.05). ILC from 0.1g of beef, pork, chicken, fish , or egg white were added to 400$\mu$g ferric iron in pH 2 HCL, the pH raised to 7,2, and soluble iron determined in the supernatant after centrifugation at 2,500g for 10 min. Iron solubilizing capabilities of ILC were pork (99.9$\pm$0.1%)>beef(93.6$\pm$3.5%)> chicken (75.8$\pm$1.8%) > fish(64.6%$\pm$3.6%)>egg white(50.9$\pm$0.9%)(p<0.05). The compositional and physico-chemical characteristics of the ILC from the above dietary protein sources were investigated.

• Journal of Korea Foundry Society
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• v.15 no.2
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• pp.146-155
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• 1995

This study was performed to investigate the effect of austempering temperature on the mechanical properties and fracture characteristics of the ductile cast iron with Cu, Mo and Cu, Mo, Ni. The results obtained from this study are summarized as follows; Microstructures of Cu-Mo and Cu-Mo-Ni ductile cast iron by austempering were obtained low bainite with some martensite at $250^{\circ}C$, mixture structure of upper and low bainite obtained at $300^{\circ}C$ and upper bainite obtained at $350^{\circ}C$. Tensile, impact and fracture toughness properties were remarkably controlled by retained austenite. With increasing austempering temperature, tensile and yield strength, hardness decreased, while the elongation and impact absorption energy, fracture toughness increased. With adding Ni, tensile and yield strength increased and elongation, facture toughness and impact absorption energy decreased. Retained austenite increased with increasing austempering temperature and the fracture surface were shown mixture structure of fibrous and dimple.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.558-564
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• 2003

A $3{\times}3$ (Fe$\times$VA) experiment with repeats was designed to study the interaction between iron and vitamin A in broilers. 504 broilers were divided into 9 groups (50% males, 50% femals), each group with 4 repeats. Iron supplemental amount was 0, 30 and 60 mg/kg; Vitamin A supplemental amount was 750, 1,500 and 2,700 IU/kg. Iron concentration in liver, serum, tibia and duodenum and vitamin A concentration in liver and serum were measured, and erythrocyte count was also observed. Results showed with the increase of dietary supplemental iron levels, vitamin A concentration in liver significantly decreased lineally (p<0.05) (0.861, 0.671, 0.639 mg/100 g at the end of 4th week; 0.900, 0.765, 0.739 mg/100 g at the end of 7th week), and vitamin A concentration in serum significantly increased lineally (p<0.05) (82.725, 97.842, $109.475{\mu}g/100mL$ at the end of 4th week; 62.288, 91.900, $95.117{\mu}g/100mL$ at the end of 7th week), meaning iron could promote the mobilization of vitamin A from liver to serum. With the increase of dietary supplemental vitamin A levels, liver iron concentration decreased and serum iron concentration increased, vitamin A could promote the mobilization of iron from liver to blood. Iron concentration in Duodenum and tibia and erythrocyte count increased significantly with higher dietary vitamin A supplementation (p<0.01), vitamin A could promote iron absorption, iron mobilization from liver to target tissues and erythropoiesis. Effects of the interaction between iron and vitamin A on vitamin A concentrations in liver and serum, iron concentration in tibia and erythrocyte count were significant (p<0.05).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.998-1002
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• 1997

This study has been performed to predict beam absorption with analysis of temperature field by using a FEM in co /sab 2/ laser hardening and to invesrigate into some effects of power density and travel speed of laser beam on the microstructure and hardness of ductile cast iron treated by laser surface hardening technique. Optical micrograph has shown that large martensite and small amount of retained austenite appear in inside hardened zone. Hardness measurement has revealed that the range of maximum hardness value is Hv=415 .+-. 10. The power density increases and the travel speed decreases, the depth of hardened zone increases due to increase of input power density.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.399-403
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• 2002

The complex of iron(II) tris(3-Br-phen) (3-Br-phen; 3-bromo-1,10-phenanthroline) was prepared as a precursor of electropolymerization and the crystal structure of [Fe(3-Br-phen)3]($PF_6$)2${\cdot}$CH3CN with a distorted octahedral geometry has been investigated. The reductive electropolymerization of $>[Fe(3-Br-phen)3]^{2+}$ complex onto the surface of a glassy carbon electrode and indium tin oxide (ITO) optically transparent electrode were performed in acetonitrile at room temperature. Thin film of poly-$>[Fe(3-Br-phen)3]^{2+}$ formed was adherent, electroactive and stably deposited on a glassy carbon disk electrode. The thin metallopolymeric film formed was also confirmed by absorption spectroscopy.

• Korean Journal of Veterinary Service
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• v.35 no.4
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• pp.307-312
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• 2012

Iron deficiency anemia is also recognized as a serious disorder in many livestock, especially, piglets. We previously studied that the iron-fortified yeast (Saccharomyces cerevisiae) producing Sus scrofa ferritin heavy-chain (FER) was bioavailable to mice with iron deficiency. In this study, we determined whether FER could improve iron deficiency in piglets. The bioavailability of FER was examined by measuring body weight gain, hemoglobin concentration and hematocrit value in suckling and weaning piglets. We found that FER significantly increased hemoglobin value and the hematocrit ratio in suckling piglets (P<0.05). Furthermore, FER treatment significantly enhanced body weight gain in both groups of the suckling and weaning piglets (P<0.05). These results suggest that the iron-fortified recombinant yeast strain is helpful in iron absorption in piglets.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.5
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• pp.418-428
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• 1990

This study measured each daily intake and excretion of iron copper and cobalt of eight 20-26 years old college men during four weeks by means of analyzing their food intake urine and feces keeping their normal living pattern and maintenance body weight. This study also compared the actual measurement value of iron intake by atomic absorption spectrophoto-meter with the conversion value of it by food table. The results were as follows. Each person's average intake daily was iron 9.19±0.32mg/day, copper 0.56±0.06mg/day and cobalt 1.86±0.18mg/day. Each person's average urinary excretion daily was iron 0.53±0.07mg/day, copper 0.07±0.03mg/day and cobalt 0.13±0.01mg/day. Each person's average fecal excretion daily was iron 1.73±0.14mg/day copper 0.16±0.01mg/day and cobalt 0.46±0.08mg/day. The actual measurement value was 9.19±0.32mg/day and its conversion value 14.07±0.29mg/day : the former was 35% lower than the latter.

• Journal of Preventive Medicine and Public Health
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• v.22 no.4 s.28
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• pp.486-494
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• 1989

Lead, iron, and zinc concentrations in whole blood were determined by atomic absorption spectrophotometry, using a simple one-step dilution procedure, which were measured in 3 groups, 98 officers unexposed to dust or to metal, 58 coal miners without pneumoconiosis, and 113 coal workers' pneumoconiosis (CWP) patients. The results were as follows : 1. The precisions (C. V.%) of lead, iron, and zinc in blood were $12.65{\pm}6.95%,\;1.47{\pm}1.25%\;and\;6.35{\pm}3.34%$, respectively. 2. Lead and zinc in blood showed the log-normal distribution unlike iron in blood which showed normal distribution. 3. Lead, iron, and zinc concentrations in blood of 3 groups were follows : There was significant difference of concentration for zinc in blood by groups statistically. 4. The difference of lead, iron, and zinc concentrations in blood was not significant (p>0.05) by profusion on chest radiographs.

• Current Applied Physics
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• v.18 no.11
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• pp.1410-1414
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• 2018

Magnetic nanoparticles (MNP) have attracted considerable interest in many fields of research and applied science due to their impressive properties. In the past, especially biomedical problems have promoted the development of MNPs. For technical applications e.g. wastewater treatment and absorption of electromagnetic waves, the existing synthesis approaches are too expensive and/or the producible quantities are too low. In this work we present a method for simple preparation of size-controlled magnetic iron oxide nanoparticles by electroerosion dispersion (EED) of carbon steel in water. We describe the synthesis method, the laboratory installation and discuss the structural, chemical and electromagnetic properties of the synthetized EED powders as well as their applicability for microwave absorption compared to other available ferrite powders.