• 한국도로학회:학술대회논문집
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• 2010.03a
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• pp.63-71
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• 2010

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.735-741
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• 1999

The effects of supplementation with nitrogen molasses mineral blocks and molasses urea mix during and immediately prior to the dry season on the production of dairy cows were studied on-station and on-farm near Morogoro, Tanzania. Supplementation of blocks to on-station cows also receiving ad libitum grass hay and 6 kg/d of maize bran increased milk production from 6.7 L/d to 11.2 L/d (p<0.05), increased dry matter intake from 10.1 kg/d to 12.0 kg/d (p<0.05), but did not significantly affect milk composition, intake of hay, and live weight changes. This increase in milk yield is mainly explained by increased intakes of energy and nitrogen. Supplementation with the molasses urea mix increased daily milk yield from 6.7 L/d to 8.8 L/d (p<0.05), but did not significantly affect the other measured production parameters. The on-farm supplementation of the blocks increased daily milk yield by 1.5 L/d in the dry season (p<0.05). This supplementation did not increase milk yields prior to the dry season, since quality forage was still available. Taking the production costs into account, supplementation with the blocks and supplementation with mix were cost effective if milk yields increased by 0.7 L/d. Hence supplementation with blocks and supplementation with mix were effective on-station, and supplementation with blocks was cost effective on-farm during the dry season.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.107-116
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• 2013

PURPOSES: The liquid-type chemical warm-mix asphalt (WMA) additive has been developed. This study evaluates the basic properties of the additive and the mechanical properties of WMA asphalt and mixture manufactured by using the newly developed chemical additive. METHODS: First, the newly developed WMA additive was applied to the original asphalt by various composition of additive components and dosage ratio of additive. These WMA asphalt binders were evaluated in terms of penetration, softening point, rotational viscosity, and PG grade. Based on the binder test results, one best candidate was chosen to apply to the mixture and then the mechanical properties of WMA mixture were evaluated for moisture susceptibility, dynamic modulus, and rutting and fatigue resistance. RESULTS : According to the binder test, WMA asphalt binders showed the similar properties to the original asphalt binder except the penetraion index of WMA additive was a little higher than original binder. From the Superpave mix design, the optimum asphalt content and volumetric properties of WMA mixture were almost the same with those of hot mix asphalt (HMA) mixture even though the production and compaction temperatures were $30^{\circ}C$ lower for the WMA mixture. From the first set of performance evaluation, it was found that the WMA mixture would have some problem in moisture susceptibility. The additive was modified to improve the resistance to moisture and the second set of performance evaluation showed that the WMA mixture with modified chemical additive would have the similar performance to HMA mixture. CONCLUSIONS : Based on the various laboratory tests, it was concluded that the newly developed chemical WMA additve could be successfully used to produce the WMA mixture with the comparable performance to the HMA mixture. These laboratory evaluations should be confirmed by applying this additive to the field and monitoring the long-term performance of the pavement, which are scheduled in the near future.

• Journal of the Korea Concrete Institute
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• v.17 no.2 s.86
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• pp.293-302
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• 2005

This study describes data from determination of the optimum mix proportion and site application of the mass concrete placed in bottom slab and side wall having a large depth and section as main structures of LNG in-ground tank. This concrete requires low heat hydration, excellent balance between workability and consistency because concreting work of LNG in-ground tank is usually classified by under-pumping, adaptation of longer vertical and horizontal pumping line than ordinary pumping condition. For this purpose, low heat Portland cement and lime stone powder as cementitious materials are selected and design factors including unit cement and water content, water-binder ratio, fine aggregate ratio and adiabatic temperature rising are tested in the laboratory and batch plant. As experimental results, the optimum unit cement and water content are selected under $270kg/m^3$ and $l55{\~}l60 kg/m^3$ separately to control adiabatic temperature rising below $30^{\circ}C$ and to improve properties of the fresh and hardened concrete. Also, considering test results of the confined water ratio($\beta$p) and deformable coefficient(Ep), $30\%$ of lime stone powder by cement weight is selected as the optimum replacement ratio. After mix proportions of 5cases are tested and compared the adiabatic temperature rising($Q^{\infty}$, r), tensile and compressive strength, modulus of elasticity, teases satisfied with the required performances are chosen as the optimum mix design proportions of the side wall and bottom slab concrete. $Q^{\infty}$ and r are proved smaller than those of another project. Before application in the site, properties of the fresh concrete and actual mixing time by its ampere load are checked in the batch plant. Based on the results of this study, the optimum mix proportions of the massive concrete are applied successfully to the bottom slab and side wall in LNG in-ground tank.

• Advances in concrete construction
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• v.12 no.6
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• pp.479-490
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• 2021

Present research is mainly focused on, microstructural and durability analysis of Graphene Oxide (GO) in Wollastonite (WO) induced cement mortar with silica fume. The study was conducted by evaluating the mechanical properties (compressive and flexural strength), durability properties (water absorption, sorptivity and sulphate resistance) and microstructural analysis by SEM. Cement mortar mix prepared by replacing 10% ordinary portland cement with SF was considered as the control mix. Wollastonite replacement level varied from 0 to 20% by weight of cement. The optimum replacement of wollastonite was found to be 15% and this was followed by four sets of mortar specimens with varying substitution levels of cementitious material with GO at dosage rates of 0.1%, 0.2%, 0.3% and 0.4% by weight. The results indicated that the addition of up to 15%WO and 0.3% GO improves the hydration process and increase the compressive strength and flexural strength of the mortar due to the pore volume reduction, thereby strengthening the mortar mix. The resistance to water penetration and sulphate attack of mortar mixes were generally improved with the dosage of GO in presence of 15% Wollastonite and 10% silica fume content in the mortar mix. Furthermore, FE-SEM test results showed that the WO influences the lattice framework of the cement hydration products increasing the bonding between silica fume particles and cement. The optimum mix containing 0.3% GO with 15% WO replacement exhibited extensive C-S-H formation along with a uniform densified structure indicating that calcium meta-silicate has filled the pores.

• Magazine of the Korea Concrete Institute
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• v.11 no.2
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• pp.139-145
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• 1999

The objective of this study is to provide the information on the small-scale model mix proportion when the behavior of prototype concrete pavement is studied through small-scale model experiments. However it is difficult to obtain a model material to simulate the prototype concrete by scaling the individual components according to the laws of similitude. In this paper, the stress-strain behavior in uniaxial compression is used as a means to correlate material similitude between the prototype and the model concrete. Based on the results of experiments, we compared the stress-strain curves of prototype and model concrete mixes using a nondimensional basis. In order to simulate the stress-stain curves of prototype concrete, it is important that various mix proportions of model concrete selected properly which are varied from aggregate grading, cement-aggregate and sand-aggregate ratio.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.643-649
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• 2004

Pork was cooked using three kinds of instrument [electric pill (EG) for 5min., microwave oven (MW) for 6min. and reheated using a MW] and then extracted with $80\%$ methanol. The Ames test was performed on the methanol extracts, employing the S. typhimurium tester strain, TA100. The methanol extract of cooked pork showed high mutagenicity ion the 5.0 mg/plate without the S9 mix, but a higher mutagenicity was induced with the S9 mix With increasing refrigeration $(4^{\circ}C)$ and freezing $(-18^{\circ}C)$ periods the extracts showed higher mutagenicities and TBA values, and the same results where shown with reheating. Correlations of the mutagenicity (-S9 mix) and rancidity of the pork cooked by EG, according to storage at and $-18^{\circ}C$ and reheated by MW (1 min), were r=0.85, 0.86, 0.98 and 0.83, respectively. When the MW was used for reheating, the refrigeration storage (r=0.98) showed a higher correlation coefficient than for that stored frozen (r=0.83). From the structure of cooked pork, as observed by SEM, many vapor pathways were viewed in the pork reheated using themicrowave oven.

• Korean Journal of Pharmacognosy
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• v.30 no.1
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• pp.12-17
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• 1999

The youngkaechulgamtang (Y) composed of four herb drugs, including Hoelen (H). Cinnamomi Ramulus (C). Atractylodis Rhizoma Alba (A) and Glycyrrhizae Radix (G). In oriental medicine literatures, Youngkaechulgamtang is described to be effective in headache, inflammation, uremia, gastritis, diarrhea and hypertension. To estimate the clinical effectiveness of Youngkaechulgamtang, several pharmacological experiments were carried out. The results are summerized as follows; On acetaminophen-induced hepatotoxicity, C+A, Y-G, Y-H, MIX and Y showed the significant elevation of glutathione-S-transferase. But, C+A, Y-G, Y-H, MIX and Y showed the significant suppression of serum aminotransferases. On ANIT-induced cholestasis, U (Ursodesoxycholic acid 50 mg/kg)+$Y_l$ (760 mg/kg) showed the significant increase of bile juice volume. $Y_l,\;Y_2$ (1520 mg/kg), U, $U+Y_l$ showed the remarkable increase of cholic acid. U and $U+Y_l$ showed the significant decrease of total bilirubin. From these results, it is suggest that Y shows liver protective effect against various hepatic injury. Especially, Youngkaechulgamtang was more effective than mixture of 4 ingredients in the elevation of glutathione-S-transferase in acetaminophen-induced hepatotoxicity.

• Korean Journal of Medicinal Crop Science
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• v.19 no.3
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• pp.170-176
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• 2011

This study was carried out to investigate whether Chrysanthermum zawadskii var. latilobum Kitamura (C. zawadskii) extracts has an inhibitory effect against the mutagenicity by cigarette smoke condensates (CSC). C. zawadskii was extracted with 70% ethanol and the yield was 18.5%. We further fractioned 70% ethanol extract sequentially to diethylether, chloroform, dichloromethane, and aqueous water, and gained the yield of 17.5%, 5.6%, 5.8%, 32.8% and 35.5%, respectively. In the Ames test, there was no mutagenic effect of crude extract and its solvent fractions up to 2 mg/plate toward Salmonella typhimurium TA 98 with or without S-9 mix metabolic activations. On the contrary, the crude extract showed an inhibitory activity against the mutagenicity of CSC in the presence of S-9 mix metabolic activation. Diethyl ether layer among five solvent fractions showed the highest inhibitory activity. The inhibitory activity of diethyl ether fraction was also increased in a dose-dependent manner and the inhibitory rate was about 97.7% at the concentration of 1 mg/plate. In this study, we conclude that crude extract of C. zawadskii itself is potentially safe for mutagenicity, and the diethyl ether fraction has an inhibitory effect against the mutagenicity of CSC.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.445-448
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• 2006

Mix design of C80A which is applied to the vertical members of The Burj Dubai Tower, the tallest building of the world, was performed so as to meet the requirements of rheological property, mechanical properties & construction sequences based on material analysis in Dubai, UAE. Experimental investigations were carried out to evaluate & optimize the quantities of total binders, the proportions of Micro Silica, Dune Sand & PFA, changes of S/a and the comparison of chemical admixture, etc. Approximately $65,000m^3$ of C80A concrete has been poured to the vertical members since 16-Apr-2006. In the actual application, it was showed that C80A has proper early strength achievement, excellent mechanical properties and satisfactory flowability & workability. The results of extensive site testing can be summarized that the average compressive strength at 28days is 98.8MPa, the average elastic modulus at 28days is 47.8GPa, the flow of concrete after pumping at the height of 250m (L72) was over 500mm.