• Journal of the Mineralogical Society of Korea
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• v.23 no.2
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• pp.151-159
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• 2010

The effect of calcite and gypsum on the hydration of Portland cement was investigated using GEM-PSI, a geochemical model. Addition of calcite and gypsum up to 5 wt% of total cement clinker into Portland cement was found to influence the hydrate assemblage of the hydrated cement in different ways. The results of geochemical modelling showed that the fraction of calcium monocarbonate increased by the hydration of cement with the increase of calcite addition. The results of modelling also indicated that gypsum increased the fraction of ettringite in the assemblage of hydrated cement as the amount of gypsum added increases. This study showed that porosity generated by the hydration of cement had a significant relation with the amount of calcite and gypsum added. The porosity of hydrated cement was lower when calcite added up to 3 wt% of cement clinker compared to the hydrated cement with the same amount of gypsum addition. However, when calcite added more than 3% of cement clinker, the porosity of hydrated cement were higher than that of hydrated cement with the same amount of gypsum addition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.908-913
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• 2008

This study was carried out to investigate the effects of Salicornia herbacea L. on baking properties of white breads. Crude fiber and crude ash contents of Salicornia herbacea L. powder were 70.02% and 25.6%, respectively. Fe and Ca contents of Salicornia herbacea L. were 176 ppm and 1,175 ppm, respectively. The pH of dough with Salicornia herbacea L. powder was similar to that of control. Salinity contents did not show any significantly differences between bread added Salicornia herbacea L. powder and control. L (lightness) and b (yellowness) value of the dough were decreased by the addition of Salicornia herbacea L., but a (redness) value was increased. The volume of dough during fermentation and the baking loss did not show significant difference between treatments and control. The weight of bread was increased by the addition of Salicornia herbacea L. but the volume was not.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.401-407
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• 2017

This study investigated the effect of roasted rice bran (RRB) on bread quality. Bread containing RRB showed small and specific loaf volumes. Baking and cooling loss rates of bread with RRB were lower than bread without RRB. The pH of bread decreased and total titratable acidity increased with increase in the amount of RRB. Water activity (Aw) and moisture contents of bread increased with RRB levels in bread. Bread containing RRB presented lower L value and higher redness (a) and yellowness (b) values. Crumb hardness, springiness, and gumminess increased, whereas cohesiveness decreased upon addition of RRB. Addition of 5% RRB resulted in higher scores in sensory evaluation than the control, however, bread with 15% RRB had the lowest score. Therefore, 5% RRB can be used in bread production.

• Korean Journal of Environmental Biology
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• v.31 no.2
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• pp.69-77
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• 2013

Toxic effects of arsenic (As) and chromium (Cr) has been investigated using the sea urchin (Hemicentrotus pulcherrimus) germ cell and pluteus-larvae. The gametotoxic and embryotoxic effects of As and Cr on H. plucherrimus were each investigated at 6.25, 12.5, 25, 50, 100. Spawning was induced by 0.5 M KCl solution and the normal fertilization and embryogenesis rates were performed for 10 min and 64 hrs after fertilization, respectively. The normal fertilization and embryogenesis rates in the control condition (not including As and Cr) were greater than 94% and 93%, respectively. The fertilization rate was not significantly changed compared with control but embryogenesis rate was significantly decreased with concentration-dependent manner. As and Cr reduced normal embryogenesis rates and a significant reduction occurred at concentration greater than 6.25 ppb (P<0.01) and 25 ppb (P<0.05), respectively. The lowest-observedeffect- concentration (LOEC) of normal embryogenesis rate in As and Cr were each 6.25 and 25 ppb, respectively. From these results, normal embryogenesis rate of H. pulcherrimus have toxic effect at greater than the 6.25 ppb concentration of As and 25 ppb concentration of Cr in marine ecosystems. These results suggest that the normal embryogenesis rates of H. pulcherrimus are very useful test method for the toxicity assessment of heavy metal as As and Cr in marine ecosystems.

• Journal of Aquaculture
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• v.21 no.4
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• pp.213-217
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• 2008

This study investigated the effect of supplement of the pigment source in diets on body color for round tailed paradise fish Macropodus chinensis and the pale chub Zacco platypus. Fish (the round tailed paradise fish: 1.6 g/ fish, pale chub: 2.4 g/fish) were fed diets containing various pigment sources (Porphyra powder, Spirulina powder. yeast astaxanthin and paprika extract) twice a day for 6 weeks. Survival of all treatments was above 80%. Weight gain and total carotenoid contents of round tailed paradise fish fed the diet containing Porphyra powder was higher than that of fish fed the other diets. The apparent redness of skin and fin in round tailed paradise fish fed the diets containing paprika extract and yeast astaxanthin was better than that of fish fed the diets containing Porphyra powder, Spirulina powder and the control diet. Weight gain and total carotenoid contents of pale chub fed the diet containing paprika extract were higher than that of fish fed the containing Porphyra powder, yeast astaxanthin, Spirulina powder and the control diet. The apparent redness of skin and fin in pale chub fed the diets containing parika extract and yeast astaxanthin was better than that of fish fed the diets containing Porphyra powder, Spirulina and the control diet. The results of this study suggest that dietary supplementation with paprika extract and yeast astaxanthin can improve redness of skin and fin of round tailed paradise fish and pale chub.

• Culinary science and hospitality research
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• v.21 no.3
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• pp.1-12
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• 2015

The purpose of this study was to investigate the quality characteristics of muffins prepared with saccharin. The effect of saccharin was evaluated in terms of height, weight, volume, specific volume, baking loss rate, image analysis, color, texture, moisture contents and acceptance test. Height, weight, volume and specific volume of muffins increased with the addition of saccharin. The baking loss rate of the samples containing saccharin was lower than those of the control group. Crust thickness of muffins containing saccharin evaluated with crumbScan decreased as the content of saccharin increased. Lightness of crust decreased significantly as contents of saccharin decreased, whereas lightness of crumb increased. Control without saccharin showed the most hardness by TPA. During storage, moisture contents increased significantly as the amount of saccharin increased. According to the acceptance test, muffins with saccharin exhibited higher scores than muffins with sugar except for color of crust and flavor. In particular, Samples 1 and 2 had the highest scores. Based on the above results, the addition of saccharin would be appropriate for making muffins.

• Journal of Aquaculture
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• v.11 no.1
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• pp.83-90
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• 1998

The effects of Obosan in the diet on growth, percent weight gain, specific growth rate, feed conversion ration and body composition of nile tilpia were investigated. First feeding fry average weighing 11.0 mg were fed the diets containing 0%, 0.25%, 0.5%, 1.0% and 2.0% Obosan for 7 weeks. Body weight, percent weight gain, specific growith rate of fish fed the diets containing 0.25%, 0.5% and 1.0% Obosan were significantly higher than control diet (P<0.05). Feed conversion ratio of fish fed the diets containing 0.25% and 0.5% Obosan showed best results compare to other experimental groups (P<0.05). Juvenile average weighing 281.0g and adult fish average weighing 563.0g were fed control and 0.3% Obosan supplemented diet for 30 days and 175 days, respectively. Body weight, percent weight gain and specific growth rate were significantly higher in the fish fed Obosan supplemented diet than control diet (P<0.05). Crude protein, crude lipid, crude ash and moisture of dorsal muscle and liver were not significantly different between two experimental groups.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.203-209
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• 2021

The quality characteristics of yellow layer cakes produced by different methods of buckwheat powder addition (0, 10, 20, 30, 40) were investigated. The specific gravity of the dough increased as the amount of buckwheat powder added increased. Regarding the color of the crumb of cake, the L value and b value(yellowness) were lower as the amount of buckwheat powder added increased, but the a value(redness) increased. The cake volume tended to decrease as the amount of buckwheat powder added increased. The cake symmetry index and uniformity index were not significantly different from those of the control group, but the baking loss rate was slightly lower when buckwheat powder was added. The hardness was significantly higher than that of the control as the amount of buckwheat powder added increased. A sensory test showed that the taste had a high score when 20% buckwheat powder was added, and texture and overall acceptance were not significantly different from the control group until 20% buckwheat powder was added. Therefore, when a part of wheat flour is replaced with buckwheat powder to produce a yellow layer cake, it is possible to produce a product with improved cake quality and symbolic characteristics when a buckwheat powder 20% level is added.

• Journal of the Korean Wood Science and Technology
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• v.39 no.4
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• pp.359-369
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• 2011

The study was carried out to investigate the quality characteristics of pellets manufactured with adding soybean oil, waste soybean oil, ozonized soybean oil and ozonized waste soybean oil to Larix kaemferi Carr sawdust. The characteristics of pellet included moisture contents, heating value, ash contents, apparent densities, durabilities, absorption ratio and elementary analysis. Moisture contents were shown 7.66~9.48% which satisfied the first grade (less than 10%) of quality standard of wood pellets announced by Korea Forest Research Institute. The heating value of the manufactured wood pellets in this study exceeded the first grade of quality standard (more than 4,300 kcal/kg) and it appeared that the pellets manufactured with adding oils and ozonized oils had more heating value than the control pellets. Ash contents 0.34~0.42% also passed the first grade (less than 0.7%) of quality standard and apparent densities were adequate for the first grade (640 kg/$m^3$) on the quality standard. Durabilities of the pellets manufactured with adding soybean oil and ozonized waste soybean oil were shown over the first grade (97.5 kg/$m^3$) of quality standard. In the general results of durabilities, the pellets manufactured with additives had better values than the control pellets. After 24 hours absorption ratio experiment, absorption ratio of pellets manufactured with additives also appeared much lower moisture absorption than the control pellets and they still had the same results after 5days absorption ratio experiment. Elementary analysis of the sulfur content was satisfied the first grade (less than 0.05%) of quality standard of wood pellets and the nitrogen content was also adequate for the first grade (less than 0.3%) of quality standard of wood pellets.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.129-133
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• 1997

본 연구에서는 LiNbO$_3$ 단결정 소재의 광손상에 대한 저항성을 향상시키는 첨가물로 잘 알려져 이쓴 MgO 및 ZnO를 첨가하여 육성한 조화용융조성(congruent melting composition)의 LiNbO$_3$ 단결정의 domain 구조는 이들 dopants를 첨가함에 따라 single domain에서 ring 형태의 주기적인 domains으로 변화함을 확인하였고, 첨가된 이온이 domain 형성에 미치는 영향을 전자현미경(SEM-WDS)으로 관찰하였다. 또한, 육성한 [Li1-5xNb5(x-y)Mg(or Zn)5y]Nb1-4x+3yO3 단결정들의 유전율(전이온도) 변화 및 광학적 특성[광투과율, 굴절률]을 측정하여 undoped LiNbO$_3$단결정과 비교하였다. 첨가물을 첨가함에 따라 전이온도는 약 20~3$0^{\circ}C$정도 증가하였으며, 10-3 order의 굴절률 변동치를 나타내었다. 또한, 육성된 결정들의 투과율은 대체로 70~80%를 나타내었고, 첨가물을 첨가함에 따라 흡수단과 OH- 흡수 band는 단파장쪽으로 각각 약 5~10nm, 40nm이동됨을 확인하였다. 이는 LiNbO$_3$단결정의 광손상 저항성이 향상되었음을 간접적으로 보여주는 결과이다.