• Journal of the Korean Magnetics Society
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• v.9 no.4
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• pp.217-222
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• 1999

The pick up impurity was studied for preparing the NiCuZn ferrite powder by a ball milling method that usually uses in the industrial ceramic process. The raw materials of NiO, CuO, ZnO, and $Fe_2O_3$ powder were weighted according to various spinel composition and mixed for 18 hrs by a wet ball milling method after that the slurry was followed by spray dried and calcined at $700^{\circ}C$ 3 hrs. The calcined NCZF powder was finally ball milled during 65 hrs as same method. The stainless steel ball and jar are used as mixing and milling equipment and the solid concentration of the slurry was 25 vol%. The impurities, stainless steel pickup, were effected by the composition of raw materials especially iron oxide, nickel oxide in the mixing process and by the rate of calcine of NiCuZn ferrite in final milling process. The empirical equation of stainless steel pickup was driven in the wet ball milling system. Finally, the composition of NiCuZn ferrite could be controlled by the empirical equation.

• Journal of Powder Materials
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• v.16 no.5
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• pp.316-325
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• 2009

Fe based (Fe$_{68.2}$C$_{5.9}$Si$_{3.5}$B$_{6.7}$P$_{9.6}$Cr$_{2.1}$Mo$_{2.0}$Al$_{2.0}$) amorphous powder, which is a composition of iron blast cast slag, were produced by a gas atomization process, and sequently mixed with ductile Cu powder by a mechanical ball milling process. The experiment results show that the as-prepared Fe amorphous powders less than 90 $\mu$m in size has a fully amorphous phase and its weight fraction was about 73.7%. The as-atomized amorphous Fe powders had a complete spherical shape with very clean surface. Differential scanning calorimetric results of the as-atomized Fe powders less than 90 $\mu$m showed that the glass transition, T$_g$, onset crystallization, T$_x$, and super-cooled liquid range $\Delta$T=T$_x$-T$_g$ were 512, 548 and 36$^{\circ}C$, respectively. Fe amorphous powders were mixed and deformed well with 10 wt.% Cu by using AGO-2 high energy ball mill under 500 rpm.

• Journal of Powder Materials
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• v.28 no.6
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• pp.483-490
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• 2021

A new Fe-Cr-Mo-B-C amorphous alloy is designed, which offers high mechanical strength, corrosion resistance as well as high glass-forming ability and its gas-atomized amorphous powder is deposited on an ASTM A213-T91 steel substrate using the high-velocity oxygen fuel (HVOF) process. The hybrid coating layer, consisting of nanocrystalline and amorphous phases, exhibits strong bonding features with the substrate, without revealing significant pore formation. By the coating process, it is possible to obtain a dense structure in which pores are hardly observed not only inside the coating layer but also at the interface between the coating layer and the substrate. The coating layer exhibits good adhesive strength as well as good wear resistance, making it suitable for coating layers for biomass applications.

• The Korean Journal of Food And Nutrition
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• v.34 no.6
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• pp.593-603
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• 2021

In this study, Korean Hallabong produced in Jeju Island and coffee were grafted to prepare coffee containing Hallabong extract and the nutritional components were analyzed. As the amount of Hallabong extract increased, the water content and total polyphenol content increased. However, the crude flour, crude protein, and total flavonoid content decreased significantly. The selenium content per 100 g was 91.28 mg in the 1% Hallabong group, and the iron content was 6.84 mg in the 3% Hallabong group. As the content of Hallabong extract in coffee increased, the L-value (brightness) and b-value (yellowness) increased, but the a-value (redness) showed a tendency to decrease. In the case of DPPH(2,2-Diphenyl-1-picrylhydrazyl) radical scavenging activity, the group containing 9% of Hallabong extract showed the highest value at 47.20 μmol/g of TEAC. In particular, the ABTS(2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonate)) and DPPH radical scavenging activity were significantly increased from coffee powder containing 6% or more of Hallabong extract(p<0.05). The caffeine content decreased as the amount of Hallabong extract added to coffee increased. Therefore, when making powder coffee with Hallabong extract added, it is recommended to set the content of Hallabong extract to 6%.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.753-758
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• 2007

This study was conducted to investigate the antioxidant activity of paprika in the lard-pork model system adding ground fresh paprika (3%) and paprika powders (5%). Paprika powders were obtained through 4 drying methods (freeze, vacuum, far infrared-ray, and hot-air). In the lard and meat-fat mixture (containing lard 30%) containing paprika powders, the rate of increase in the peroxide value (POV) and thiobarbituric acid (TBA) value decreased notably during the refrigerated storage ($4^{\circ}C$) compared to the control without paprika. Therefore, paprika powders showed potent antioxidant activity and especially the freeze dried paprika powder revealed the most effective activity among them. However, its antioxidant activity was still lower than that of the fresh paprika because the addition of fresh paprika in the lard and meat-fat mixture merely increased the POV and TBA value. In linoleic acid oxidation, the addition of capsanthin 500 ppm to mixed linoleic acid and 10 ppm of $FeCl_3$ (LF) inhibited the formation of peroxides by 15.2% compared to LF, showing its iron scavenging ability. When mixed antioxidants (${\beta}$-carotene 200 ppm + ascorbic acid 100 ppm, capsanthin 200 ppm + ascorbic acid 100 ppm) were added in LF, synergistic effects were obtained with 57.7 and 60.4% of inhibition of peroxide formation, respectively.

• Particle and aerosol research
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• v.4 no.2
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• pp.51-67
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• 2008

In this study, we devoted to kinetic measurement of the catalytic oxidation of iron-containing flame soot particles and better understanding the role of catalytic particles on carbon oxidation in particular at low temperature, targeting on autothermal regeneration of diesel particulate filter by diesel exhaust gas. Carbon-based Fe-containing particles generated by spraying ferrocene-doped diesel fuel in an oxy-hydrogen flame are tested and compared with a commercial carbon black powder for thermogravimetric analysis (TGA), secondary ion mass spectrometry (SIMS), Fourier-transform infrared spectroscopy (FTIR), Induced coupled plasma-Atomic emission spectroscopy (ICP-AES), and High-resolution transmission electron microscopy (HR-TEM). As a result, we found that a small amount of the ferrocene addition led to significant reductions in a on-set temperature and an activation energy of the carbon oxidation as well. An oxygenated surface complex forming at the particle surface could be thought as active species that would be readily consumed in particular at low temperature.

• Journal of the Korean Home Economics Association
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• v.41 no.8
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• pp.55-62
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• 2003

Natural dyes generally fan into two categories; organic dyes coming from animals and plants and inorganic dyes obtained from various minerals such as bengala, loess, ultramarine, prussian blue and etc. The main components of volcanic ash is clay mineral such as kaolinite, illite, quartz. Clay minerals Composing volcanic ash are kaolinite［$Al_4Si_4O_{10}{(OH)_{8}}$］, illite［$K_{X}Al_2(Si,\;Al)_4O_{10}{(OH)}_2$］, quartz［$SiO_2$］, homblende［$Na_{0-1}\;Ca_2{(Mg,\;Fe,\;Al)}_5{(Si,\;Al)}_{8}O_{22}{(OH)}_2$］and etc. And the redish color mainly comes from iron oxide. In this paper, two different classes of dyeing process were tested; dyeing with volcanic ash only and cationic agent pre-treatment followed by dyeing with volcanic ash. The compositions of the volcanic ash powder and the volcanic ash deposited on the cotton knitted fabrics identified by energy dispersive spectrometer and XRD analysis. The major chemical components of volcanic ash deposited on the cotton knitted fabrics were confirmed to be the saicon oxide, iron oxide, and aluminum oxide and etc. According to the analysis by XRD and EDS-SEM, kaolinite, illite and quartz were also identified.

• Journal of Forest and Environmental Science
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• v.32 no.2
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• pp.103-112
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• 2016

To compare seed components of plus trees, seed powder ground after seedcoat removal was analyzed for two oak species, i. e., Quercus monglica (white oak) and Quercus variabilis (red oak), which are typical oak trees in Korea but have different fruiting characteristics. Thus we aimed at analyzing and comparing many ingredients including minerals, sugars, etc. Two species were similar to each other in the content of water, crude ash, crude protein and carbohydrates, but crude lipid content in Q. variabilis was 2.5 times higher than that in Q. mongolica. Crude proteins of Clone 124 was 1.5 times higher than that of Clone 75 in Q. mongolica. Crude lipid content showed the highest value in Clone 0511 of Q. variabilis, and more phosphate and iron was found in Q. monglica than in Q. variabilis. Glucose showed 85.4% and 88.3% on average of the total monosacchrides in two species, and galactose and arabinose were also found. In the content of phosphate, iron, and crude lipid, differences were found between two species and among clones of two species.

• Journal of the Mineralogical Society of Korea
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• v.14 no.2
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• pp.111-118
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• 2001

The use of bacteria as a novel biotechnology to facilitate the production of nanoparticles is in its infancy. Cobalt-substituted magnetite nanoparticles were synthesized by a thermophilic iron(III)-reducing bacterium, TOR-39, under anaerobic conditions using amorphous Fe(III) oxyhydroxides plus cobalt ( $Co^{2+}$ and $Co^{3+}$ ) as an electron acceptor and organic carbon as an electron donor. Microbial processes produced copious amounts of nm-sized cobalt substituted magnetites. Chemical analysis and X-ray powder diffraction analysis showed that cobalt was substituted into biologically facilitated magnetites. Microbially facilitated synthesis of the cobalt-substituted magnetites may expand the possible use of the specialized ferromagnetic particles.

• Advances in Traditional Medicine
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• v.7 no.5
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• pp.466-476
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• 2008

We have developed the tablet formulation of Triticum aestivum (wheatgrass) and investigated clinically, its effects in patients suffering from b-thalassemia (major) at K. T. Children Hospital, Civil Hospital, Rajkot. The tablets (wheatgrass powder 250 mg.) were given 3 times in a day for 9 months. Blood samples were collected at the start, after 6 months and 9 months and analyzed for various biochemical and hematological parameters. Treatment with wheatgrass formulation for 9 months produced significant decrease in hemoglobin, total RBC, eosinophil and reticulocyte counts. The mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) were significantly increased was significantly increased. The serum ferritin was also significantly decreased. There was no influence on serum magnesium, serum iron and Thiobarbituric acid reacting substances (TBARS). Our data indicate that treatment with wheatgrass on patients with $\beta$-thalassemia (major) may have beneficial effects in the form of a decrease in ineffective erythropoiesis, stimulation of hemoglobin synthesis in RBC, decrease in iron load and decrease in eosinophil count.