• Particle and aerosol research
• /
• v.5 no.1
• /
• pp.1-7
• /
• 2009

Fe- and V-doped titanium dioxide nanoparticles consisting of spherical primary nanoparticles were synthesized from a mixed liquid precursor by using the flame spray pyrolysis. The effects of dopant concentration on the powder properties such as morphology, crystal structure, and light adsorption were analyzed by TEM, XRD, and UV-Vis spectrophotometer, respectively. As the V/Ti molar ratio increased, pure anatase particles were synthesized. On the contrary, rutile phase particles were synthesized as the Fe/Ti ratio increased. Photocatalytic property of as-prepared $TiO_2:Fe,V$ nanoparticles was investigated by measuring the removal efficiency for volatile organic compounds (VOCs) under the irradiation of visible light. After 2 hrs under visible light, the removal efficiencies of benzene, p-xylene, ethylbenzene, and toluene were reached to 21.9%, 21.4%, 19.8% and 17.6% respectively.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2001.05a
• /
• pp.25-30
• /
• 2001

The purpose of this study is to present a basic data about the workability of high strength concrete to apply to a field of construction work. The main parameters are as follows; environmental temperature, elapsed time and the use of mineral admixture or not under the same mixing proportions. From the result, Adding amounts of superplasticizer to get a target slump were different in the respective temperature condition. Slump loss according to elapsed time was influenced by environmental temperature. the amount of superplasticizer and the slump loss were decreased by using mineral admixture(garnet powder) and by making concrete under lower temperature.

• Transactions of the Korean hydrogen and new energy society
• /
• v.17 no.1
• /
• pp.109-116
• /
• 2006

The heat treatment characteristics of natural talc sample was investigated in diverse analytical view point. The mass decrease comes to heat treatment was resulted by the continuous and the discontinuous process and the obtained result show very similar two step profiles with 8.9 % mass decrease. The dehydroxylation of -OH groups contained talc crystal was analyzed by spectroscopic method and the crystallographic variations was also observed after heat treatment. According to XPS result, the magnesium hydroxide($Mg(OH)_2$) of untreated talc powder changed to magnesium oxides(MgO) after heat treatment.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1999.04a
• /
• pp.95-101
• /
• 1999

This study was performed to evaluate the characteristics of workability and strength of the concrete containing mineral admixtures such as flyash, blast furnace slag, zeolite powder. As a result, considering their workability and strength, the optimum replacement ratio of them to plain concrete were obtained for each ternary admixture. This increased compressive strength was ascribed to both the closer parkinof fine particles and pozzolan reactivity of powders. This work showed that could be effectively utilized as a blending material without any decrease in the strength of early hydration stage. On the other hand, we found that the compressive strength at early ages ternary ordinary and high strength concrete untill 7 days was small, but that ternary concrete at 28days was highly increased about 31% and 15% extent.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2005.05b
• /
• pp.473-476
• /
• 2005

Silica fume has merits of filling the voids, enhancement of reheological chracteristics, prduction of secondary hydrates by pozzolanic reaction in reactive powder concretes. However silica fume has been imported in high-cost in domestic industry, we need to investigate replaceable material in stead of silica fume in a view of economy Therefore, in this paper, in order to investigation replacement of silica fume in ultra-high strength SFRCC we used another mineral admixtures like that fly-ash, blast slag.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.10
• /
• pp.1453-1459
• /
• 2011

This research was performed to determine the quality characteristics of cookies made from flour added with 0, 1, 3, and 5% sea mustard (Undaria pinnatifida Suringer) powder. The quality characteristics of the cookies, including pH and density of the dough, moisture content, spread factor, loss rate, leavening rate, color, mineral content, texture properties, and sensory properties, were estimated. The density of the dough, water content, spread factor, loss rate, leavening rate, a and b values of color scale, and mineral content of the cookies significantly increased while those of pH, L value, and hardness decreased with higher content of sea mustard powder. With the exception of flavor, consumer acceptability scores in terms of appearance, taste, texture, and overall preference for cookies made from 3% sea mustard powder significantly ranked the highest. Taken together, the results of this study suggest that addition of 3% sea mustard powder to flour is effective for increasing the consumer acceptability and functionality of cookies.

• Food Science of Animal Resources
• /
• v.36 no.3
• /
• pp.397-404
• /
• 2016

The objective of this study was to determine the effect of dietary supplementation with whey powder (WP, 1g/kg feed) from weaning to slaughter (150 d) on dry-aged loin quality of pigs. Fifty-eight pigs were randomly divided into two dietary treatment groups (seven replications of four pigs per treatments). Basal diet with 0.1% whey powder was supplied to the WP group. Basal diet was used for the control group (CON). Diet whey protein did not appear to influence the moisture or protein contents. However, ash and fat contents were significantly (p<0.05) decreased in the WP group compared to the control group. Drip loss was significantly (p<0.05) lower in the WP group than that of the control group. Increasing redness with decreasing lightness was found in the inner loin of the WP group. Calcium and iron contents in the WP group were significantly higher than those in the control group. Protein degradation was higher in the WP group than that in the control group (p<0.05), whereas shear force was lower in the WP group than that in the control group (p<0.05). In conclusion, the basal diet supplemented with 0.1% whey powder influence negatively the lipid oxidation of meat whereas the texture property and mineral composition of meat from whey powder fed pigs are developed.

• Food Science and Preservation
• /
• v.13 no.6
• /
• pp.697-702
• /
• 2006

This study investigated the quality characteristics of sulgidduck prepared by the addition of astringent persimmon powder. For Sulg : dduck, the amounts of added astringent persimmon powder were 0, 5, 10, 15, 20%. With the addition of astringent persimmon powder content the moisture content of persimmon sulgidduck (sulgidduck prepared by adding astringent persimmon powder) decreased. With increasing addition of those, Reducing sugar, free sugar and mineral (Ca, K and Mg) of persimmon sulgidduck were increased significantly. L-value in color decreased whereas a- and b-values were increased. Adhesiveness, cohesiveness, gumminess and chewiness in textural profile analysis were decreased. However, there is no respective comparison hole. These result suggest that persimmon sulgidduck can be used as rice cakes commercially desired.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.04a
• /
• pp.441-444
• /
• 2008

Ultra high performance concrete (UHPC) in this study is composed of sand, cement, silica fume, siliceous powder, superplasticizer and steel fiber. UHPC is composed of fine mineral particles below 0.5mm in diameter. In general, siliceous powder improves the mechanical properties of concrete by physical and chemical effect. Physical effect is related with filling interior voids which weaken the mechanical properties and chemical effect with reaction of $SiO_2$ with cement hydrates in a condition of high temperature and pressure. We evaluated the effect of siliceous powder's particle size on the mechanical properties of ultra high performance concrete in air pressure and $90^{\circ}C$ steam curing condition. siliceous powder's particle size in this study is in the range of $2{\mu}m$ to $26{\mu}m$. Fluidity in a fresh concrete, compressive strength, ultimate strain, elastic modulus and flexural strength in a hardened concrete was evaluated. We could find out that the smaller siliceous powder's particle size is, the better the fluidity and strength properties.

• Fire Science and Engineering
• /
• v.32 no.3
• /
• pp.27-34
• /
• 2018

A Semi-Incombustible Composite Insulation Board (SICIB) that can be applied to building construction and ships was developed. The SICIBs comprised of pine leaf powder, vermiculite. The incombustibility, semi-incombustibility, and U-factor of the developed SICIBs were measured. The incombustibility of the each SICIB was determined by the proportion of combustible flexible binder and pine leaf powder. SICIB satisfied the incombustibility test without a combustible flexible binder and pine leaf powder. In addition, SICIB with 6% of pine leaf ensured its semi-incombustible performance. A combustible flexible binder or pine leaf powder over 6% failed the fire-resistant performance of SICIB. In addition, SICIBs with incombustible/semi-incombustible finishing and a 200 mm insulating layer (glass wool and sprayed poly urethane foam) met the U-factor of an external wall for buildings described in the Korean building code.