• Journal of Power System Engineering
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• v.9 no.4
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• pp.130-136
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• 2005

The effects of additional Mg content, the size and volume fraction of reinforcement phase on the mechanical properties of ceramic particle reinforced aluminium matrix composites fabricated by pressureless metal infiltration process were investigated. The hardness of $SiC_p/AC8A$ composites increased gradually with an increase in the additive Mg content, while the bending strength of $SiC_p/AC8A$ composites increased with an increase in additive Mg content up to 5%. However, this decreased when the level of additive Mg content was greater than 5% due to the formation of coarse precipitates by excessive Mg reaction and an increase in the porosity level. The hardness and strength of the composites increased with decreasing the size of SiC particle. It was found that the composites with smaller particles enhanced the interfacial bonding than those with bigger particles from fractography of the composites. The hardness of $Al_2O_{3p}/AC8A$ composites increased gradually with an increase in the volume fraction, however, the bending strength of $Al_2O_{3p}/AC8A$ composites decreased when the volume fraction of alumina particle was greater than 40% owing to the high porosity level.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.218-222
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• 1999

The effects of storage temperature, moisture content and the concentration of additives, such as sucrose fatty acid ester(SE), isomaltooligosaccharide(IO) and glycerin(GL), on texture properties, hardness(HA), cohesiveness(CO) and chewiness(CH) of Baikseolgi after 7 days storage were analyzed by response surface methodology(RSM). The contour values of HA of SE added Baikseolgi at 20, 50 and $80^{\circ}C$ of storage temperate were $1500{\sim}3200,\;500{\sim}1300$ and $100{\sim}400\;g_f$, respectively. The HA of IO or GL added Baikseolgi decreased with increased storage temperature, moisture content and additive concentration. The storage temperature was the most significant factor affecting the HA of Baikseolgi. However, the second and third significant factors were moisture content and additive concentration, respectively. These results imply that the control of storage temperature is the most effective method to increase the storage stability of Baikseolgi. The CO of IO or GL added Baikseolgi was increased by the change of strage temperature from $20{\circ}\;to\;50{\circ}$. While, there was no significant difference between $50{\circ}\;and\;80{\circ}$ of storage temperature. The CO of IO or GL added Baikseolgi was maximized around 40% of moisture content and that of GL added Baikseolgi was minimized around 0.5% of GL concentration. The storage temperature, additive concentration and moisture content were the first, second and third affacing factors on the CO of Baikseolgi, respectively. The CH of Baikeolgi was decreased by increasing storage temperature, moisture content and additive concentration. The storage temperature, moisture content and additive concentration were the first, second and third affacting factors on the CH of Baikseolgi, respectively.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.283-288
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• 1999

This study is performed to evaluate slump , air content, compressive strength and length change ratio of non-shrinkage high strength ocncrete is achieved by 10% expansive additive contained. The length change ration of non-shrinkage high strength concrete which is in water curing, shows 0.055% expansion in 10% expansive additive contained concrete and 0.308 expansion in 20% expansion additive contained concrete when it is curing 28 days.

• Journal of Surface Science and Engineering
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• v.36 no.6
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• pp.437-443
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• 2003

The effects of additive(grain refiner, GR) on process efficiency of the Ni-Fe-P alloy electrodeposition and the material properties of the deposit were investigated. Electrochemical properties of the deposits were investigated using polarization and electrochemical impedance techniques, and the material properties of the deposits were characterized through inductively coupled plasma(ICP), spiral contractometer, XRD, SEM and TEM. When the additive was added into the electrodeposition bath, current efficiency, Ni content and corrosion resistance of the deposit increased, whereas residual stress, surface roughness and grain size of the deposit decreased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.5
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• pp.402-410
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• 2000

The electrical properties and stability of Pr$_{6}$/O$_{11}$-based ZnO wvaristors consisting of ZnO-Pr$_{6}$/O$_{11}$-CoO-Dy$_{2}$/O$_{3}$ based ceramics were investigated in the Dy$_{2}$/O$_{3}$ additive content range o 0.0 to 2.0 mol%. The density was nearly constant 5.62 g/cm$^3$corresponding to 97% of theoretical density as Dy$_{2}$/O$_{3}$ additive content increases up to 0.5 mol%. However the density decreased as Dy$_{2}$/O sub 3/ additive content is further additive content. Pr$_{6}$/O$_{11}$-based ZnO varistors doped with 0.5mol% Dy$_{2}$/O$_{3}$ exhibited a good nonlinearity, which is 37.76 in the nonlinear exponent and 5.36 $mutextrm{A}$ in the leakage current. And they exhibited very stress (0.80 V$_{1mA}$/9$0^{\circ}C$/12h)+(0.85 V$_{1mA}$/115$^{\circ}C$/12h)+(0.95 V$_{1mA}$/1$25^{\circ}C$/12h). Consequently it was estimated that ZnO-0.5 mol% Pr$_{6}$/O$_{11}$-1.0 mol% CoO-0.5 mol% Dy$_{2}$/O$_{3}$ based ceramics will be sufficiently used as a basic composition to develop the advanced Pr$_{6}$/O$_{11}$-based ZnO varistors in the future.he future.uture.he future.

• Journal of Environmental Science International
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• v.31 no.2
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• pp.215-218
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• 2022

This study investigated the effect of adding poultry litter additive containing probiotics and amino acids to the litter on weight gain in ducks and ammonia content in poultry litter. Nine hundred 1-day-old ducks (Pekin) were randomly distributed into three groups (300 birds per treatment divided into three replicates) using a randomized block design. Treatments were top-dressed on the litter surface at rates of 2 kg poultry litter additives (T1) and 2 kg macsumsuk (T2) per m², and untreated poultry litter was used as the control. Overall, a significant difference (p<0.05) in weight gains was observed at 3 and 4 weeks, but not at 5 and 6 weeks. After 4 weeks, when compared to other treatments, the addition of poultry litter additive tended to increase the average body weight gain (90-130 g). The ammonia content was affected by all treatments (p<0.05) over time except at 3 weeks, however, compared to other treatments, the poultry litter additive decreased the ammonia content. In particular, the rate of ammonia reduction by the poultry litter additives over time was approximately 20.2%-49.2%. Regarding temperature, a significant difference was observed in all treatment groups (p<0.05), except at 3 weeks. In conclusion, considering poultry litter additives and temperature, the increase in duck weight gain was associated with a decrease in ammonia content in the poultry litter.

• Journal of the Korea Institute of Building Construction
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• v.7 no.3
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• pp.123-130
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• 2007

This study investigated the fundamental properties and shrinkage properties of high performance concrete with water/binder ratio of 0, 30 and with combination of expansive additive and shrinkage reducing agent. According to the results, the fluidity of high performance concrete showed lower the using method in combination with expansive additive and shrinkage reducing agent than the separately using method of that, so the amount of superplasticizer increased when the adding ratio of expansive additive and shrinkage reducing agent increased. However the air content of concrete increased when used in combination with expansive additive and shrinkage reducing agent, so the amount of AE agent decreased. The compressive strength showed the highest at 5% of expansive additive, and decreased with an increase of the amount of shrinkage reducing agent. Furthermore, in order to reduce the shrinkage of high performance concrete, it was found that the using method in combination with expansive additive and shrinkage reducing agent was more effective than separately using method of that. Autogenous shrinkage was predicted using JCI model. Because JCI model is unable to consider the effect of EA and SRA, correction factor should be added to enhance the accuracy.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.58-64
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• 2004

The shrinkages of injection molded parts are different in molding operational conditions, resins and additives. The shrinkage of injection molded part for crystalline polymer, PBT (polybutylene terephthalate) has been studied for various operational conditions of injection molding and content of additives. Mica was used as a additive to PBT to examine the part shrinkage according to the mica content. The part shrinkages of mica contained PBT decreased as mica content increases. Higher injection temperature and injection pressure resulted in a lower shrinkage. As mold temperature increases the part shrinkage decreased. The part shrinkage of flow direction was less than that of the perpendicular direction to the flow for both pure and mica contained PBT. However the shrinkage difference between flow and perpendicular to flow directions decreased as mica content increased.

• Electrical & Electronic Materials
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• v.9 no.6
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• pp.542-550
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• 1996

ZnO-based ceramic varistors containing NiO range 0.5 mol% to 4.0 mol% were fabricated by standard ceramic techniques. The influence of NiO on the microstructure and electrical behavior of ZnO varistor was investigated. As the content of NiO additive increases, average grain size decreased from 16.5.mu.m to 13.2.mu.m, and the amount of NiO existing in the grain interior and grain boundary region was approximately equal. NiO acted as an acceptor which decreases donor concentration due to the increase of Zn vacancy in the grain, and as a driver which migrates Zn interstitial in the depletion region toward the interface of grain boundary, which resulted in the decrease of interface state density. As a result, increasing the content of NiO additive, barrier height, nonlinear exponent, and varistor voltage decreased, and leakage current increased. Wholly, the physical and electrical properties of the ZnO varistor can be said to be affected by the NiO additive.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.6
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• pp.115-121
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• 2000

The purpose of this research is to investigate properties and field application of non-shrinkage high strength concrete containing expansive additive. Before the field applications, several basic laboratory test are performed to evaluate the characteristics of air content, workability and strength of the concrete using calcium sulfa aluminate(CSA) expansive additive. As a result, high strength concrete using CSA expansive additive show similar workability and compressive strength to that normal concrete, and the optimum replacement ratio of them is obtained by 10% CSA expansive additive. Accordingly, it can be concluded that the use of CSA expansive additive is effective to prevent shrinkage crack and to achieve volume stability of concrete structure.