• Tribology and Lubricants
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• v.15 no.1
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• pp.77-82
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• 1999

The processing conditions fur the synthesis of platelet W $S_2$ lubricant powder through a solid-gas reaction were optimized. The mixture of tungsten and sulfur powders were sealed in a vacuum of 10$^{-6}$ torr, prior to heat-treating at 85$0^{\circ}C$ fur 8 days. The reaction product showed a well-developed platelet W $S_2$ powder with an average size of 3.8 ${\mu}{\textrm}{m}$. The TGA/DTA analysis of the synthesized W $S_2$ powder was performed up to 120$0^{\circ}C$ at a rate of 1$0^{\circ}C$/min in flowing air (100 ${\mu}{\textrm}{m}$/min) atmosphere. The weight loss was about 6% up to 120$0^{\circ}C$ compared to the original weight. A rapid weight loss of about 5% occurred in the temperature range of 44$0^{\circ}C$ to 66$0^{\circ}C$ and an exothermic peak observed due to the transition of W $S_2$ to W $O_3$. The synthesized W $S_2$powder was coated on the commercial deep grooved ball bearing (No. 6203) to examine the effect of W $S_2$, coating layer on the noise and endurance of the ball bearing. The level of noise obtained from W $S_2$, coated-ball bearing (56 ㏈) was higher. than the value (32 ㏈) occurred in the case of greece lubrication. The endurance of the ball-bearing assembled after the coating of W $S_2$ powder onto each part increased 50 times compared to the non-coated ball-bearing..

• Journal of Powder Materials
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• v.16 no.4
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• pp.249-253
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• 2009

3-D shape soft magnetic composite parts can be formed by general compaction method of powder metallurgy. In this study, the results on the high density nanostructured Fe-Si/Fe composite prepared by a warm compaction method were presented. Ball-milled Fe-25 wt.%Si powder, pure Fe powder and Si-polymer were mixed and then the powder mixture was compacted at various temperatures and pressures. Pore free density of samples up to 95% theoretical value has been obtained. The warm compacted sample prepared at 650 MPa and 240$^{\circ}C$ had highest compaction properties in comparison with other compacts prepared at 300, 400 MPa and room temperature and 120$^{\circ}C$. The magnetic properties such as core loss, magnetization saturation and coercivity were measured by B-H curve analyzer and vibration sample magnetometer.

• Journal of Powder Materials
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• v.21 no.6
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• pp.422-428
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• 2014

In this study, the reduction kinetics and behaviors of oxides in the water-atomized iron powder have been evaluated as a function of temperature ranging $850-1000^{\circ}C$ in hydrogen environment, and compared to the reduction behaviors of individual iron oxides including $Fe_2O_3$, $Fe_3O_4$ and FeO. The water-atomized iron powder contained a significant amount of iron oxides, mainly $Fe_3O_4$ and FeO, which were formed as a partially-continuous surface layer and an inner inclusion. During hydrogen reduction, a significant weight loss in the iron powder occurred in the initial stage of 10 min by the reduction of surface oxides, and then further reduction underwent slowly with increasing time. A higher temperature in the hydrogen reduction promoted a high purity of iron powder, but no significant change in the reduction occurred above $950^{\circ}C$. Sequence reduction process by an alternating environment of hydrogen and inert gases effectively removed the oxide scale in the iron powder, which lowered reduction temperature and/or shortened reduction time.

• Korean journal of food and cookery science
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• v.21 no.4 s.88
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• pp.416-421
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• 2005

This study was conducted to investigate the effect of the addition of moroheiya powder on the baking qualities of the bread. Three different powder concentration levels of $0.2\%,\;0.5\%\;and\;1.0\%$ were added to flour to make the bread. The volume of the bread dough containing moroheiya powder tended to be increased compared to that of control during the fermentation period. The percentage of baking loss of the bread containing moroheiya powder tended to be less than that of control. In the texture analyzer measurement, the hardness of the bread was significantly increased by adding the moroheiya powder Springiness, gumminess and brittleness of the bread tended to increase and were all higher in the bread containing $0.5\%$ moroheya powder than in the other breads. In sensory evaluation, the bread containing $0.2\%$ moroheiya powder showed a similar tendency with control and showed the best scores, especially in taste.

• Journal of Powder Materials
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• v.14 no.5
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• pp.298-302
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• 2007

In recent years, a rapid increase in demands for the soft magnetic composite parts has been created and it has been tried to improve their properties by various processing methods, alloying elements and compaction parameters. Warm compaction method has been used for the reduction of residual stress, the improvement of magnetic properties and the higher densities. In this work, the effects of warm compaction and polymer binder on magnetic properties of Fe powder core were investigated. The sintering powder, Fe oxide, was ball-milled for 30n hours. And then ball-milled Fe oxide powder was reduced through hydrogen reduction process. The hydrogen reduced Fe powder and polymer binder were mixed by 3-D turbular mixer. And then the mixed powder was warm-compacted. The magnetic properties such as core loss and permeability were measured by B-H curve analyzer.

• Korean journal of food and cookery science
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• v.31 no.6
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• pp.703-717
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• 2015

In this study, when we reflect the preference of consumers who wish to receive their health through natural materials, and whose purpose is to receive good quality and good tasting cookies made from ginger. After 0%, 2%, 4%, 6%, 8% of flour was replaced by ginger powder for making cookies, a comparative analysis of quality characteristics and QDA was completed. Adding ginger powder caused a decrease in the density of the cookie dough, moisture content, loss rate and leavening rate of cookie (p<0.05), but the hardness of the ginger cookie increased. As a result of the description analysis of adding ginger powder, adding ginger powder increases, cookie color, crispiness, acid taste, flavor, and an after taste, but not the sweetness of the cookie. In terms of cookie color, crispiness, taste, flavor and overall acceptability, adding 4% ginger powder received high reviews. Also as a result of measuring DPPH radical elimination, ginger powder shows to have good antioxidant activity. So their anti-cancer activity is better than cookies without ginger powder. Therefore, we expect that we can fulfill the overall acceptability.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.799-804
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• 2008

This study was performed to determine physicochemical and sensory quality of low-fat pork loaf containing silkworm powder and vegetable worm (Paecilomyces japonica). Total 2% of fat replacer (soy protein isolate:maltodextrin:$\kappa$-carrageenan:water=1:0.5:0.5:10, w/v) was added. The loaf was separated into CTL (control), T1 (0.2% silkworm powder), T2 (0.2% vegetable worm), T3 (0.4% silkworm powder), T4 (0.4% vegetable worm), T5 (0.1% silkworm powder+0.1% vegetable worm), and T6 (0.2% silkworm powder+0.2% vegetable worm). Pork loaf of T3 showed the highest pH value and cooking loss of pork loaves containing silkworm and vegetable worm was higher than control at day 5. 2-Thiobarbituric acid reactive substances of T2 and T5 showed significantly lower values than control and those additives may reduce lipid oxidation of meat. Overall acceptability was not adversely influenced by silkworm powder and vegetable worm at day 0 and 5. These results indicated that those silkworm powder and vegetable worm could be utilized for pork product industry.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.1087-1095
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• 2017

We examined the quality characteristics of pound cake with prepared Aronia melanocarpa powder, which included the physical characteristics, antioxidant activity and sensory evaluation in this study. Pound cakes were prepared with various ratios of Aronia powder (0, 5, 10, 15, 20%). No significant difference in loss rate or weight was found from increased Aronia powder concentration. The color of pound cake was darker and reddish with the addition of Aronia powder. Lightness (L) and yellowness (b) significantly decreased with the addition of Aronia powder, whereas redness (a) increased (p<0.05). the qualities of hardness, cohesiveness, gumminess and chewiness of the pound cake prepared with the addition of Aronia powder were significantly increased when compared to control(p<0.05), with exception of 20% addtion. Total phenolic contents and DPPH radical scavenging activity was significantly elevated by the addition of Aronia powder(p<0.05). The pound cake with 10% Aronia powder showed the strongest positive sensory properties with regard to taste and overall palatibility. These results suggest that the addition of 10 % Aronia to pound cake batter could well serve to improve the overall quality, texture and taste of the final product.

• The Korean Journal of Food And Nutrition
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• v.34 no.1
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• pp.1-14
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• 2021

This study evaluated the antioxidant activity and quality characteristics of rice cookie with added butterbur powder in a ratio of 0, 5, 10, 15, and 20% to confirm the possibility of butterbur as a functional food. The moisture content, spread factor, leavening rate, and hardness of rice cookies increased with an increase in the amount of butterbur powder; whereas a decrease in the pH and baking loss rate was observed. The L and b values decreased as the amount of butterbur powder increased, but the value was the lowest when 5% of butterbur powder was added. The sensory liking score showed the highest preference for 10% butterbur powder regarding appearance, flavor, taste, texture, and overall preference. In the principal component analysis (PCA), the addition of 10% butterbur powder positively affected the measure of food acceptance in terms of organoleptic properties of butterbur. Besides, as the amount of added butterbur powder increased, the antioxidant activity of rice cookies increased. Based on these results, it appears that the addition of butterbur powder to rice cookies in a 10% ratio can produce rice cookies with excellent antioxidant activity, overall quality, and high preference.

• Journal of the Korean Society of Food Culture
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• v.38 no.6
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• pp.425-433
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• 2023

We determined physicochemical characteristics and antioxidant activities of cookies prepared by replacing wheat flour with 0, 3, 6, and 9% freeze-dried burdock powder instead of wheat flour. The leavening and loss rates of the cookies decreased in proportion to the amount of burdock powder added to the dough. The moisture content of the cookies increased in proportion to the amount of burdock powder added and the crude protein and hardness were higher in the burdock-added group compared to the control. The lightness and yellowness of the cookies decreased, and the redness increased in proportion to the amount of burdock powder added. The total flavonoid and polyphenol compounds in the cookies increased in proportion to the amounts of burdock powder added. The antioxidant activities also tended to increase in proportion to the amount of burdock powder added. Based on the above results, adding burdock powder to cookies can increase antioxidant activity by increasing the content of antioxidant components, such as polyphenols and flavonoids. In addition, it is believed that adding burdock powder at levels of 3 to 9% of the weight of flour would result in cookies with spreadability, swelling power, and hardness similar to those of regular cookies.