• Journal of Magnetics
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• v.19 no.1
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• pp.49-54
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• 2014

The influence regarding the dehydrogenation speed, at the desorption-recombination state during the hydrogenation-disproportionation-desorption-recombination (HDDR) process, on the microstructure and magnetic properties of Nd-Fe-B magnetic powders has been studied. Strip cast Nd-Fe-B-based alloys were subjected to the HDDR process after the homogenization heat treatment. During the desorption-recombination stage, both the pumping speed and time of hydrogen were systematically changed in order to control the speed of the desorption-recombination reaction. The magnetic properties of HDDR powders were improved as the pumping speed of hydrogen at the desorption-recombination stage was decreased. The lower pumping speed resulted in a smaller grain size and higher DoA. The coercivity and the remanence of the 200-300 ${\mu}m$ sized HDDR powder increased from 12.7 to 14.6 kOe and from 8.9 to 10.0 kG, respectively. In addition, the remanence was further increased to 11.8 kG by milling the powders down to about 25-90 ${\mu}m$, resulting in $(BH)_{max}$ of 28.8 MGOe.

• Journal of Powder Materials
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• v.15 no.4
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• pp.292-296
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• 2008

The electromagnetic (EM) wave absorption properties of the $Fe_{73}Si_{16}B_7Nb_3Cu_1$ nanocrystalline powder mixed with 5 to 20 vol% of Ni-Zn ferrites has been investigated in a frequency range from 100MHz to 10GHz. Amorphous ribbons prepared by a planar flow casting process were pulverized and milled after annealing at 425 for 1 hour. The powder was mixed with a ferrite powder at various volume ratios to tape-cast into a 1.0mm thick sheet. Results showed that the EM wave absorption sheet with Ni-Zn ferrite powder reduced complex permittivity due to low dielectric constant of ferrite compared with nanocrystalline powder, while that with 5 vol% of ferrite showed relatively higher imaginary part of permeability. The sheet mixed with 5 vol% ferrite powder showed the best electromagnetic wave absorption properties at high frequency ranges, which resulted from the increased imaginary part of permeability due to reduced eddy current.

• Korean journal of food and cookery science
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• v.30 no.4
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• pp.419-427
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• 2014

This study was carried out to evaluate the effects of stevia leaf powder on bread quality. Different breads were prepared by the addition of 0%, 0.5%, 1.0%, 1.5% and 2.0% stevia leaf powder to wheat flour. The weight of the breads containing stevia leaf powder ranged from 525.0~543.5 g, while that of the control was 548.8 g. The volume of the breads prepared by adding stevia leaf powder was 2225.0~2278.8 mL, while that of the control was 2307.5 mL. The height and specific volume of the breads decreased with the addition of stevia leaf powder. The Hunter L values of the breads also decreased, whereas a and b values increased with the addition of stevia leaf powder. The L and b values of the bread decreased continuously during storage. The hardness, springiness, cohesiveness and chewiness all increased with the addition of stevia leaf powder. Overall the acceptability and taste determined by sensory evaluation of the bread with 1.5% stevia leaf powder were better than that of the control.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.190-199
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• 2016

This study was conducted to evaluate the effect of mugwort powder on the quality characteristics of sponge cake. Mugwort powder sponge cake was prepared with different ration of mugwort powder(0, 5, 10, 15, 20%). The specific gravity, baking loss rate and cake weight increases as the ration of mugwort powder. The sponge cake's a, b level increased with the increasing level of mugwort powder 20% appeared to be the highest. In terms of textural characteristics, the samples containing 5, 10, and 20% mugwort powder had significantly higher hardness than the control samples. The substance's level of springiness, and cohesiveness decreased as the mugwort powder added. In sensory evaluation, overall acceptability and taste of the cake was better than the others when 10% mugwort powder was added. The results indicated that substituting 10% mugwort powder to sponge cake is optimal for quality and provides a product with reasonable high overall acceptability.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.855-863
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• 2006

The purpose of this study was to provide the basic information on the functional cookies with pumpkin and ginseng powder. Pumpkin cookies with ginseng powder were prepared at various additions adding (0 g, 3 g, 6 g, 9 g). With increasing As the addition of ginseng powder additionincreased, there were significant decrease in the water contents and crude protein were significantly decreased (p<0.05). The spread factor and Hunter color's L, a, and b values in th dough and cookies were significantly decreased with increasing as the addition level of ginseng powder content was increased(p<0.05). Hardness measured using rheometer and onset, peak, and closing temperatures and gelatinization enthalpy using DSC showed significantly the higher values with increasing more additions of ginseng powder content. In sensory evaluation, surface cracking, and pumpkin flavor were decreased with lower levels of ginseng powder. Ginseng flavor and hardness were increased with lower levels of ginseng powder Overall desirability of cookies with addition of 3 g added ginseng powder was the highest of the four samplesproduction. Surface crakcracking washadhighly positively correlated with spread factor, a (redness) (p<0.01)and but negatively correlated with carbohydrate content (p<0.05). Ginseng aroma showed negative correlation to the water contents, crude protein, spread factor, and Hunter's a (redness) and b (yellowness) values (p<0.05).

• Food Science of Animal Resources
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• v.26 no.2
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• pp.236-240
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• 2006

This study was conducted to manufacture new value-added corn dog using potato, milk powder and egg as nutritious and surplus agricultural and livestock products. A typical corn dog was manufactured with corn dog powder, potato, milk powder and egg as the same method of conventional corn dog. Corn dogs were divided into four groups; control group A [conventional corn dog], group B [corn dog manufactured with the fixed content of corn dog powder, milk powder, and egg, potato, water (3: 3: 1: 1: 2)], group C [corn dog manufactured with the fixed content of corn dog powder, milk powder, and egg, potato, water (3: 3: 2: 1: 2)], group D [corn dog manufactured with the fixed content of corn dog powder, milk powder, and egg, potato, water (3: 3: 1: 2: 2)], Viscosity of corn dog batter, pH of corn dog, rheology and sensory evaluation were measured. There were no significant differences for viscosity and pH between original corn dog and manufactured corn dog (p>0.05). However, hardness and brittleness of manufactured corn dog D were superior to the other groups (p<0.05). Also, manufactured corn dog D was superior to the other groups by the results of sensory evaluation. Therefore, these results suggest that it may be possible to manufacture new value-added corn dog which can help to stimulate the consumption of nutritious and surplus agriculture and livestock products.

• Journal of the Korean Ceramic Society
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• v.29 no.12
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• pp.942-948
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• 1992

Ultrafine iron oxide powder, {{{{ gamma }}-Fe2O3 and $\alpha$-Fe2O3, were prepared by the thermal decomposition of organometallic compounds. The formation process of powder includes the thermal decomposition and oxidation of the organometallic precursors, Fe(N2H3COO)2(N2H4)2 (A) and N2H5Fe(N2H3COO)3.H2O (B). The organometallic precursors, A and B, were synthesized by the reaction of ferrous ion with hydrazinocarboxylic acid, and characterized by quantitative analysis and infrared spectroscopy. The mechanistic study for the thermal decomposition was performed by DAT-TG. The iron oxide powder was obtained by the heat treatment of the precursors at 20$0^{\circ}C$ and $600^{\circ}C$ for half an hour in air. The phases of the resulting product were proved {{{{ gamma }}-Fe2O3 and $\alpha$-Fe2O3 respectively. The particle shape was equiaxial and the particle size was less than 0.1 ${\mu}{\textrm}{m}$. Magnetic properties of the {{{{ gamma }}-Fe2O3 powder obtained from A and B was 234 Oe of coercivity, 64.26 emu/g of saturation magnetization, 23.59 emu/g of remanent magnetization and 24.1 Oe, 47.27 emu/g, 3.118 emu/g respectively. The value of $\alpha$-Fe2O3 powder was 1.494 Oe, 0.4862 emu/g, 0.1832 emu/g and 1,276 Oe, 0.4854 emu/g, 0.1856 emu/g respectively.

• Food Engineering Progress
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• v.15 no.1
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• pp.85-89
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• 2011

Freeze-dried Ecklonia cava powder was incorporated into cookie dough at 5 levels (0%, 1.5%, 3%, 4.5%, and 6%, w/w) by replacing equivalent amount of wheat flour of the cookie dough. After aging and sheeting, cookies were baked at $185^{\circ}C$ for 14 min in a convection oven. The baked cookies were cooled to room temperature for 30 min and packed in airtight bags prior to all measurements. Lightness $(L^*)$ decreased significantly as the E. cava powder content increased (p<0.05) and a decreasing trend in both redness ($a^*$-value) and yellowness ($b^*$-value) was observed. On the other hand, firmness increased significantly with an increase in E. cava powder content (p<0.05). Increases in E. cava powder concentration up to 6% in the cookie formulation significantly increased the intensities of all sensory attributes such as color, flavor, taste, and firmness (p<0.05). Correlation analysis indicated that the E. cava concentration correlated significantly with most of the properties except for $a^*$-value (p<0.01, 0.05, or 0.001). Properties such as firmness and sensory color and firmness correlated positively while $L^*$- and $b^*$-value correlated negatively with E. cava concentration. Sensory color correlated negatively with $L^*$- and $b^*$-value. Sensory firmness correlated positively with mechanically measured firmness.

• Journal of the Korean institute of surface engineering
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• v.50 no.3
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• pp.177-182
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• 2017

The properties of electroless Ni-B thin film on diamond powder with different parameters (temperature, pH, surfactant etc.) were studied. The surface morphology, structure and composition distribution of the Ni-B film were observed by field effect scanning electron microscope (FE-SEM), energy-dispersive spectrometer (EDS), X-ray diffraction (XRD) and Auger electron spectroscopy (AES). The growth rate of Ni-B film was increased with increase of bath temperature. The B content in Ni-B film was reduced with increase of bath pH. As a result the structure of Ni-B film was changed from amorphous to crystalline structure. The PVP in solution plays multi-functional roles as a dispersant and a stabilizer. The Ni-B film deposited with adding 0.1 mM-PVP was strongly introduced an amorphous structure with higher B content (25 at.%). Also the crystallite size of Ni-B film was reduced from 12.7 nm to 5.4 nm.

• Progress in Superconductivity
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• v.13 no.3
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• pp.184-188
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• 2012

$MgB_2$ superconducting sheets have been fabricated by powder rolling method using mixture of Mg and B powders. Sheet-type $MgB_2$ bulk samples of ~10 mm width and 50-100 mm long were squeezed out after compacted by two rotating rolls of 130 mm diameter with gap distance of 0.5 mm and speed of ~40 cm/min (~1 rpm). The nominal composition of Mg, which is ductile metal, was added up to 30% to facilitate forming the $MgB_2$ sheets. The annealed samples at $900^{\circ}C$ and 3 hrs showed superconducting transition temperature of ~32 K and critical current densities at zero fields were ${\sim}10^5A/cm^2$ at 5 K and ${\sim}5{\times}10^4A/cm^2$ at 20 K.