• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.159-163
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• 2001

Si3N4 powder has been analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). The sample was dissolved by high-pressure acid digestion with HF, H2SO4 (1+1), and HNO3 mix ture. This technique is well suited for the impurity analysis of Si3N4 because the matrix interference is eliminated. A round-robin samples trace elements, such as Ca, W, Co, Al, Fe, Mg, and Na, were determined. For the direct analysis, slurry nebulization of 0.96 mm Si3N4 powder also has been studied by ICP-AES. Emission intensities of Fe were measured as ICP operational conditions were changed. Significant signal difference between slurry particles and aqueous solution was observed in the present experiment. Analytical results of slurry injection and high-pressure acid digestion were compared. For the use of aqueous standard solution for calibration, k-factor was determined to be 1.71 for further application.

• Korean journal of food and cookery science
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• 제25권2호
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• pp.134-142
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• 2009

This study was conducted to identify the optimal mixing ratios of pomegranate powder or Opuntia humifusa powder for the production of jelly. To establish the amount of pomegranate powder or Opuntia humifusa powder that could be added to jelly, physicochemical sensory characteristics and textural properties were measured. Specifically, jellies were prepared using gelatin that contained a ratio of 0.5, 1, 1.5 and 2%(w/w) pomegranate powder or Opuntia humifusa powder. Sensory evaluation of the sweetness, chewiness, springiness, hardness, transparency and overall acceptability of jelly prepared using 0.5% pomegranate powder resulted in a high score. Similarly, the appearance, sweetness, chewiness, springiness, hardness, transparency and overall acceptability of jelly prepared using 0.5% Opuntia humifusa powder received a high score. Taken together, the results of this study suggest that pomegranate and Opuntia humifusa can be useful in the production of high quality jelly.

• Food Science and Preservation
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• 제23권4호
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• pp.488-494
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• 2016

Cheonggukjang was prepared by addition of peanut (Arachis hypogaea L.) powder in order to improve its quality and functional properties. The physicochemical and sensory properties of Cheonggukjang added peanut powder were investigated, after adding the peanut powder with the amount of 5, 15 and 25% (w/w). The proximate composition of peanut powder was as follows: moisture, 1.80%; crude protein, 24.9%; crude lipid, 48.3%; crude ash, 2.90%; and carbohydrates, 22.1%. Crude protein and lipid content of Cheonggukjang increased with increaes in the amounts of peanut powder, while the moisture content decreased. Calcium and amino acid contents showed disparity depending on the increasing addition of peanut powder. Cheonggukjang containing 15% (w/v) peanut powder was found to be highest calcium contents. The major amino acids of Cheonggukjang were glutamic acid, aspartic acid, lysine, leucine, arginine and proline. Depending on increasing amounts of peanut powder, the L and b values (measured using Hunter's color values) were decreased, while the a value was increased. In addition, pH was decreased as the amount of peanut powder was increased. Sensory scores of Cheonggukjang containing 15% (w/v) peanut powder were best when considering both quality characteristics and sensory evaluation. This study suggested that peanut powder could enhance the quality and functionality of Cheonggukjang further.

• Journal of Industrial Technology
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• 제24권B호
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• pp.65-71
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• 2004

The ultra fine gamma-alumina powder was prepared via ammonium aluminium carbonate hydroxide (AACH). The XRD, SEM, BET, thermal analysis were used to characterize the samples. The effects of various reaction parameters as concentration, of solution, anion on specific area, PH, aging time and thermal decomposition condition on the produced AACH and alumina were discussed.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.829-830
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• 2006

Recent research at Harbin Institute of Technology on the synthesis of nanocrystalline and untrafine grained materials by mechanical alloying/milling is reviewed. Examples of the materials include aluminum alloy, copper alloy, magnesium-based hydrogen storage material, and $Nd_2Fe_{14}B/{\alpha}-Fe$ magnetic nanocomposite. Details of the processes of mechanical alloying and consolidation of the mechanically alloyed nanocrystalline powder materials are presented. The microstructure characteristics and properties of the synthesized materials are addressed.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2003년도 international symposium on advanced powder metallurgy
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• pp.12-24
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• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.432-432
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• 2006

• Journal of Welding and Joining
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• 제25권3호
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• pp.64-71
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• 2007

The dissolution phenomenon of the solid phase powder and base metal by liquid phase insert metal during Transient Liquid Phase bonding using the mixed powder composed of the modified GTD111(base metal) powder and the GNi3 (Ni-l4Cr-9.5Co-3.5Al-2.5B) powder was investigated. In case of the mixed powder contains modified GTD111 powder 50wt%, all of the powder was melted by liquid phase at 1423K. At the temperature between solidus and liquidus of GNi3, liquid phase penetrated into the boundary of the modified GTD111 powder and solid particle separated from powder was melted easily because area of reaction was increased. With increasing mixing ratio of the modified GTD111, it needed the higher temperature to melt all of the modified GTD111 powder. During Transient Liquid Phase bonding using the mixed powder composed of the modified GTD111 50wt% and GNi3 50wt% as insert metal, width of the bonded interlayer was increased with increasing bonding temperature by reaction of the base metal and liquid phase in insert metal. Dissolution of the base metal and modified powder by liquid phase progressed all together and after all of the powder was melted nearly, the dissolution of the base metal occurred quickly.

• The Korean Journal of Community Living Science
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• 제22권2호
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• pp.257-265
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• 2011

To find the optimum proportion of Hydrangea serrata Seringe(HSS) powder, rice cakes were prepared with different quantities of Hydrangea serrata Seringe powder instead of sugar. Technical and sensory examinations were then conducted. The proximate components of the HSS leaves were 3.48% crude protein, 6.45% crude lipid, 7.98% crude fiber and 9.32% crude ash. The pH values of samples which replaced 25%, 50%, 75% and 100% of sugar with the HSS powder were significantly decreased(p<0.05). The groups with HSS powder showed a lower L value(lightness) and a value(redness) than that of the control group. The B value(yellowness) of the Sulgidduk containing the HSS powder was higher than that of the control group. The hardness of HS2 and HS3 was increased by the addition of the HSS powder. The adhesiveness of Sulgidduk groups with the HSS powder was higher than that of the control group. Springiness was not changed by adding the HSS powder. The cohesiveness of the Sulgidduk was significantly reduced by adding the HSS powder(p<0.001). The groups with no sugar showed the highest gumminess and chewiness. The added HSS powder caused both a darker color and a stronger odor, but the sweetness of the Sulgidduk which replaced the sugar with the HSS powder was decreased compared to the control group. The moisture content and the hardness was not affected by the addition of the HSS powder. The preference of color and taste was not changed by adding the HSS powder. The preference of flavor of the Sulgidduk with the HSS powder showed higher than that of the control. Overall acceptability of the Sulgidduk did not show any significant differences. As a result, Sulgidduk can be replaced 25% and 50% of sugar with the Hydrangea serrata Seringe powder.

• Journal of the East Asian Society of Dietary Life
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• 제27권3호
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• pp.304-312
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• 2017

This study was carried out to evaluate the effects of yam powder addition (0~40%) on the quality characteristics and oxidative stability of yackwa made with rice flour. While most rice flour (34.35%) had a particle size more than $250{\mu}m$, 75% of yam powder had a particle size less than $65{\mu}m$. Width, height, and volume of rice yackwa added with yam powder increased with increasing yam powder content. While L and b values of rice yackwa added with yam powder decreased with increasing yam powder content, a value increased. Hardness and chewiness of rice yackwa added with yam powder increased as storage period increased at $25^{\circ}C$ for 9 days, whereas they decreased with increasing yam powder content. In a discrimination test, brown color, flavor, sweetness, and bitterness increased with increasing yam powder content, whereas hardness decreased. In a preference test, taste, texture, and overall acceptance increased with increasing yam powder content. The acid and thiobarbituric acid (TBA) values of rice yackwa added with yam powder increased as storage period increased. However, acid and TBA values of the treated groups decreased with increasing yam powder content compared to the control group. Although 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activities decreased with increasing storage period, values increased with increasing yam powder content. It was found that yackwa quality, preference, and oxidative stability increased during storage with increasing yam powder content. From these results, addition of 40% yam powder would be the optimal conditions for making rice yackwa.