• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.175-176
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• 2006

The filling property of the binder treated iron based powder made of atomized iron powder was compared with that of the one made of reduced iron powder. The latter one showed a better filling property than the former one, although the original reduced powder showed a worse flow rate. Changing the particle size distribution of the original atomized powder from wide to narrow like the original reduced iron powder, improved the filling property of the binder treated powder. As a result, the particle size distribution of the original iron powder was found to strongly affect the filling property of the binder treated powder.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.173-174
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• 2006

X-ray analysis on iron ores and reduced iron powders revealed that the main acid-insoluble substances were hexagonal and tetragonal quartz, another substances were sillimanite, alumina-silicate, an unnamed zeolite, all contained Si and Al. Their particle size was in the range of $3{\sim}7\;{\mu}m$. Statistics analysis showed that the AIC for high-grade magnetite powder was $(0.130{\pm}0.010)%$) during the latest five months. The predicting value for reduced iron powder should be 0.179%. However, the testing value for reduced iron powder was $(0.192{\pm}0.014)%$. The limited difference of 0.013% might imply rare pollution coming from the reduction and milling processes. The most important step for control AIC should be the separation process of iron ore powders.

• Journal of Powder Materials
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• v.20 no.1
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• pp.43-47
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• 2013

The extraction of metallic pure vanadium powder from raw oxide has been tried by Mg-reduction. In first stage, $V_2O_5$ powders as initial raw material was reduced by hydrogen gas into $V_2O_3$ phase. $V_2O_3$ powder was reduced in next stage by magnesium gas at 1,073K for 24 hours. After reduction reaction, the MgO component mixed with reduced vanadium powder were dissolved and removed fully in 10% HCl solution for 5 hours at room temperature. The oxygen content and particle size of finally produced vanadium powders were 0.84 wt% and 1 ${\mu}m$, respectively

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.7
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• pp.736-747
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• 2011

This study investigates the current status and dyeing properties of various natural indigo powder dyes in the domestic market. Products from India, China, Europe are sold in the market and only a few manufacturers provide recommendation for the method of dyeing and information on the additives. Through the market research and the preliminary investigation on 21 products, 11 were selected for the dyeing experiment which include 3 Indian, 3 Chinese, 2 German, and 1 Pakistani origin indigo reduced powders, and 2 Indian origin dried indigo leaf powder. The two dyeing methods used were the precipitation method and the fresh juice method, both at $10^{\circ}C$, $25^{\circ}C$, and $60^{\circ}C$. Color difference, K/S value, and colorfastness of dyed cotton fabrics were examined. Indian reduced indigo powder showed the highest K/S value, deep dyeing, and the best color fastness. Chinese reduced indigo powder resulted in a more greenish and bluish color. Powders of dried indigo leaves were easy to use but resulted in a pale color due to low dye uptake.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.561-564
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• 2006

This study is aimed for investigating the engineering properties of concrete containing fly ash, slag powder and limestone powder. The results of this study are as follows; As limestone powder is incresed, slump, air loss and strength is reduced, variation ratio of length is reduced, dynamic modulus of elasticity and neutralization depth is incresed.

• Culinary science and hospitality research
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• v.19 no.4
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• pp.13-24
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• 2013

This research intends to examine the quality characteristics of madeleines after adding drying frozen mulberries by freeze drying and hot-air drying, making them powdered. The general ingredients and physiochemical characteristics of each specimen were measured, compared and analyzed. Madeleines were made based on the recipe set in practical examination of bakery technicians, in which each specimen is added with 0%(control), 1%, 3%, 5%, 7% of mulberry powder depending on the quantity of flour. And then, pH, chromaticity and texture were measured and consumer preferences were grasped by sensory testing. The test results are as follows. First of all, pH was low in the group added with hot-air drying mulberry powder. In chromaticity, brightness(L value) was reduced in comparison with the control group as the addition rates of freeze-drying mulberry powder and hot-air drying mulberry powder increased. Red chromaticity(a value) increased more when adding hot-air drying mulberry powder rather than freeze-drying mulberry powder. Yellow chromaticity(b value) was reduced as addition of mulberry powder increased. Hardness and elasticity of the group added with freeze-drying mulberry powder showed significant differences as addition of mulberry powder increased. Cohesiveness and gumminess was reduced as the addition increased. Hardness of madeleines added with hot-air drying mulberry powder showed significant differences by addition rates of mulberry powder. Elasticity increased by the quantity of mulberry addition. Cohesiveness was reduced as the addition was reduced. Gummines increased as the addition increased. As the result of sensory test on preference, the preferences of the group added with 5% of freeze-drying mulberry powder and the group added with 7% of hot-air drying mulberry powder were the highest.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.593-600
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• 2008

The principal objective of this study was to evaluate the quality characteristics of dried noodles when different concentrations of Lotus root powder were added to the wheat flour. The cooking quality, mechanical textural properties, and viscosity were measured, and a sensory evaluation was conducted with the prepared noodles. The gelatinization points of the composite Lotus root powder-wheat flours were shown to have increased and the viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity values of those samples were reduced, as the Lotus root powder content was increased as measured via amylography. As increasing amounts of Lotus root powder were added, the L and b values were reduced, and the color values, weight, and volume of the cooked noodles increased, as did the turbidity of the soup. With regard to the textural characteristics, the Lotus root powder additive increased hardness and reduced adhesiveness, cohesiveness, and springiness. Overall, the noodles prepared with 15% Lotus root powder were preferred more than the other noodles, according to the results of our sensory evaluation.

• Journal of Powder Materials
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• v.9 no.5
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• pp.329-335
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• 2002

Recently, the fabrication process of the W-Cu nanocomposite powders has been studied to improve the sinterability through the mechanical alloying and reduction of W and Cu oxide mixtures. In this study. the W-Cu composites were produced by mechanochemical process (MCP) using $WO_3-CuO$ mixtures with two different milling types of low and high energy, respectively. These ball-milled mixtures were reduced in $H_2$ atmosphere. The ball-milled and reduced powders were analyzed through XRD, SEM and TEM. The fine W-Cu powder could be obtained by the high energy ball-milling (HM) compared with the large Cu-cored structure powder by the low energy ball-milling (LM). After the HM for 20h, the W grain size of the reduced W-Cu powder was about 20-30 nm.

• The Korean Journal of Food And Nutrition
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• v.21 no.3
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• pp.306-311
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• 2008

The principal objective of this study was to assess the effects of bread supplemented with silkworm powder and cholesterol on the lipid metabolism in rats. When the rats were fed on bread supplemented with silkworm powder and cholesterol, their net weight tended to decrease as compared with the controls. Although the rats' food intake was increased, it did not increase significantly, but the feed efficiency ratio was substantially reduced. The levels of total and LDL-cholesterols were reduced, but the levels of HDL-cholesterol were increased. The HDL-cholesterol to total cholesterol ratio and level of triglyceride level were increased substantially. The atherogenic index was reduced when rats were fed on bread supplemented with silkworm powder, and thus we concluded that the bread caused an improvement in symptoms associated with high-cholesterol.

• Journal of Powder Materials
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• v.10 no.6
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• pp.422-429
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• 2003

The reduction mechanism of the composite powders mixed with $WO_3$ and CuO has been studied by using thermogravimetry (TG), X-ray diffraction, and microstructure analyses. The composite powders were made by simple Turbula mixing, spray drying, and ball-milling in a stainless steel jar with the ball to powder ratio of 32 to 1 at 80 rpm for 1 h without process controlling agents. It is observed that all the oxide composite powders are converted to W-coated Cu composite powder after reducing treatment under hydrogen atmosphere. For the formation mechanism of W-coated Cu composite powder, the sequential reduction steps are proposed as follows: CuO contained in the ball-milled composite powder is initially reduced to Cu at the temperature range from 20$0^{\circ}C$ to 30$0^{\circ}C$. Then, $WO_3$ powder is reduced to W $O_2$ via W $O_{2.9}$ and W $O_{2.72}$ at higher temperature region. Finally, the gaseous phase of $WO_3(OH)_2$ formed by reaction of $WO_2$ with water vapour migrates to previously reduced Cu and deposits on it as W reduced by hydrogen. The proposed mechanism has been proved through the model experiment which was performed by using Cu plate and $WO_3$ powder.