• Korean journal of food and cookery science
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• v.9 no.4
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• pp.261-265
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• 1993

For the purpose of supplying the information to improve the acceptability of soy paste as the condi-ment, the changes of peptide were determined. The results were as follows; Average peptide length were decreased. It was 102 at 0 day, 15 at 10 day and 4.1 at 180 day. Peptide fraction were the same as in 60 day and 180 day. Low molecular weight peptide were not changed greatly during fermention. Peptide identified in 180 day fermentation were Ala-Ser, Gly-Glu, Glu-Ser, Asp-Glu, Asp- Tyr, Asp-Ala-Ser, Ala-Ser-Glu, Glu-Ser-Ala, and Ala-Lys-Met. In the characteristics of bitter peptide in 180 day fermentation, soy paste itself didn't show bitter taste', solvent extration fraction I'showed bitter taste. After gel chromatography, fraction I, fraction II and fraction III were obtained and fraction II were bitter peptide of low molecular weight. After gel chromatography', solvent extration fraction 2'(water extration) were divided into fraction IV, V, VI,VII and VIII. Fraction IV, V and VI showed bitter taste. Amino acids composition of the fractions showing bitter taste were like that; fr. 1: Glu- (Asp, Pro, Val, lie or Leu)-Met fr. II Pro-(Glu, Val, Phe)-lle or Leu fr. IV: Glu-(Asp, Ala, Tyr, Leu of lie)-Phe fr. V: Ala-(Met, Glu, Pro)-lle or Leu fr. VI: Asp-(Phe, Ser, fly)-Val.

• Korean Journal of Animal Reproduction
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• v.26 no.2
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• pp.105-110
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• 2002

The objective of this study was to determine the developmental competence of in vitro matured oocytes after intracytoplasmic sperm injection(ICSI) with epididymal spermatozoa. The ovaries were obtained from slaughtered small species dogs. Oocytes matured in vitro for 24 hrs were fertilized by ICSI with epididymal spermatozoa. After ICSI, one group of oocytes was activated with 2.0 mM dimethylaminopurine or 7% ethanol for 5 min. and second group was not activated. The follicular oocytes were cultured in synthetic oviductal fluid(SOF) and TCM-199 medium containing hormones and 10% FCS for 24~48 hrs in a incubator with 5% $CO_2$ in air at 38.5$^{\circ}C$. 1. Results of IVM showed that the percentage of oocytes reaching MII after 24 h and 48 hrs of incubation were significantly higher(p<0.05) after culture with 48 hrs(9/30, 30.0%) than that after culture with 24hrs(a/30, 26.7%). 2. Results of IVM showed that the percentage of oocytes reaching MII after 48 hrs of incubation were significantly higher(p<0.05) after culture with SOF media(10/30, 30.3%) than TCM-199 media (7/30, 23.3%). 3. The rate of cleavaged embryos to blastocyst obtained by ICSI treated activation oocytes was significantly higher(p<0.05) than that of nonactivation oocytes(5/16, 25.0% vs 1/13, 5.0%). 4. The rates of development of cleavaged embryos to blastocyst obtained by ICSI treated sperm of fresh, epididymal and frozen-thawed epididymal were 8/18(44.43%), 5/16(31.3%), 2/14(14.3%), respectively. and these values of frozen-thawed epididymal sperm injection were lower than fresh sperm injection.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.2
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• pp.94-101
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• 2016

This paper presents an investigation into the durability alkali-activated materials(AAM) mortar and paste samples manufactured using fly-ash(FA) and ground granulated blast furnace slag(GGBFS) exposed to a sulfate environment with different GGBFS replace ratios(0, 30, 50 and 100%), sodium silicate modules($Ms[SiO_2/Na_2O]$ 1.0, 1.5 and 2.0) and initial curing temperatures($23^{\circ}C$ and $70^{\circ}C$). The tests involved immersions for a period of 6 months into 10% solutions of sodium sulfate and magnesium sulfate. The evolution of compressive strength, weight, length expansion and microstructural observation such as x-ray diffraction were studied. As a results, as higher GGBFS replace ratio or Ms shown higher compressive strengths on 28 days. In case of immersed in 10% sodium sulfate solution, the samples shows increase in long-term strength. However, for samples immersed in magnesium sulfate solutions, the general observation was that the compressive strength decreased after immersion. The most drastic reduction of compressive strength and expansion of weight and length occurred when GGBFS or Ms ratios were higher. Also, the XRD analysis of samples immersed in magnesium sulfate indicated that expansion of AAM caused by gypsum($CaSO_4{\cdot}2H_2O$); the gypsum increased up to 6 months continuously.

• Journal of the Korea Concrete Institute
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• v.24 no.6
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• pp.715-726
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• 2012

Since strength and diffusion coefficient of concrete, representative concrete properties that in change with age, the time effect must be considered in the analysis of chloride penetration. In this study, an evaluation of correlation between accelerated diffusion coefficient, apparent diffusion coefficient, and compressive strength in high performance concrete with various mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume was performed. For this work, thirty mix proportions were prepared. Accelerated diffusion coefficients at the age of 28, 91, 180, and 270 days were evaluated. For apparent diffusion coefficient, submerging test for 6 months was performed. For evaluation of compressive strength with ages, the compressive strength test was carried out at an age of 7, 28, 91, 180 days. The results of accelerated diffusion coefficient, apparent diffusion coefficient, and strength were compared, and the correlation was analyzed considering time dependency. From this study, linear relationship between accelerated diffusion and apparent diffusion coefficient were obtained regardless of concrete age. The linear relations were also observed in strength-accelerated diffusion coefficient and strength-apparent diffusion coefficient regardless of concrete age.

• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.43-51
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• 2003

Recently, to consider financial and constructive aspect usage of Admixture such as Blast-Furnace Slag and Fly-Ash, are increased. Also the use of cold-weather-concrete is increased. Blast-Furnace Slag, a by-product of steel industry, have many advantage to reduce the heat of hydration, increase in ultimate strength and etc. But it also reduces early-age strength, so it is prevented from using of Blast-Furnace Slag at cold-weather-concrete. In this study, for the purpose of increasing usage of Blast-Furnace Slag at cold-weather-concrete, it is investigated the strength properties of concrete subjected to frost damage for the cause of early age curing. The factors of this experience to give early frost damaged were Freezing temperature(-1, -10, $-15^{\circ}C$), Early curing age(0, 12, 24, 48hour), Freezing times(0, 12, 24, 48hour). According to this study, if early curing is carried out before haying frost damage, the strength of concrete used admixture, subjected to frost damage, is recovered. And that properties are considered, the effect of using admixture like blast-furnace-slag, is very high

• Journal of Energy Engineering
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• v.21 no.2
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• pp.119-123
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• 2012

Although LNG storage tanks are very delicate with chloride attack owing to its operating inshore location, specific integrity management system for chloride attack has not been studied so far. As the design warranty life time, about 25 years, has come, to prevent paying huge amount of construction cost and required resources for new alternative storage tanks and manage the life time of operating storage tanks, the basic data of chloride attack is necessary. This study intended to build up basic data for following detailed study to develop technologies for life time management of LNG storage tanks, NT Build 492 method in North Europe was used to test chloride diffusion coefficient for the newly-constructing concrete outer tank. Results of these tests lead us to the conclusion that 90 days diffusion coefficients show 46% of 28 days' due to a large quantity of fly ash mixing and much similar to estimation from concrete process table. It seems resonable to conclude that 90 days specimens are recommended estimating the chloride diffusion coefficient for LNG storage tanks to enhance the reliabilities.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.3
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• pp.255-262
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• 2020

Blended cement with fly ash and bottom ash from Circulating Fluidized Bed Combustor boiler(CFBC) burned at a low temperature, can be high heat of hydration and abnormal setting caused by higher volumn contents of Fe₂O₃, free-CaO, SO₃. In this study, the ground CFBC bottom ash powder mixed with blast furnace slag was used as substitute activator of gypsum and recycled iron slag was produced from mix and pulverized by ball mill to increase the recycling rate. The effect on compressive strength of cements with the mixture of original and hydrated bottom ash mixtures with BFS with small water, respectively, was analyzed, and it was found that the hydrated bottom ash activator was more effective in initial strength development. To improve the initial strength of blended cement, an activator mixed with a blast furnace slag and bottom ash mixing ratio of 5:95 and 10:90, respectively, the slag cement by about 6%, and it was analyzed to develop an initial strength similar to gypsum as a conventional activator.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.233-236
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• 1983

Results obtained from the experiment conducted to determine the potential distribution of greenhouse white flies are summerized as follows; Hatching rate of eggs were significantly decreased when eggs were treated under $-5^{\circ}C$ for three days and no eggs were hatched when 4he eggs were treated at $10^{\circ}C$. for three days. Kate of pupation was also decreased when larvae were subjected to $-5^{\circ}C$ for three days and no pupation of larvae was of served when the larvae were under $-20^{\circ}C$ for three days. Emergency rate of pupae was decreased when pupae were under $-20^{\circ}C$. for three days and no emergence was observed when pupae were treated at the temperature of $-20^{\circ}C$ for three days. Survival rate of adults were greatly decreased when they were under $-7.5^{\circ}C$. for three days and the adults were completely dead when they were subjected to $-10^{\circ}C$. for three days. Therefore, it may be concluded that the greenhouse white flies may be overwintered, in the from of pupae at the middle-southern part of Korea, while they may overwinter in all developmental stages in Jeju Island and in southern tip coast area of Korea.

• Analytical Science and Technology
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• v.25 no.6
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• pp.421-428
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• 2012

In this study, PCDD/PCDFs, PAHs and PCBs in wastes from metal, plastic and wastewater treatment facilities were analyzed. The concentrations of PCDD/PCDFs ranged from 7.37~432.20 ng-TEQ/kg in fly ash, 0.51~855.01 ng-TEQ/kg in incinerated ash and 0.37~385.81 ng-TEQ/kg in dust. Dioxin content was lower, compared to data in foreign countries. PAHs concentration was in the range of 0.0075~2.9225 mg/kg for process sludge and 0.0035~1.6716 mg/kg for wastewater sludge, which satisfied all of the two standards (Nap, Ant, B(a)F:4/0.8, Phen, B(a)A:5/1, Flt:10/2.5, B(a)P:4.5/0.9) of the Marine Environment Management Act. PAHs concentration in process sludge and wastewater sludge were slightly lower than those abroad. According to the analysis of seven types of PCBs (in comparison with the first standard, 0.15 mg/kg), concentration was found in the range of 0.0~0.65 mg/kg, while PCB-52, PCB-101, PCB-138, PCB-153 and PCB-180 isomers were detected in excessive value in some machine oil and hydraulic fluid.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.421-428
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• 2016

In this work, pozzolanic activities of various waste materials were compared with those of well-known by-product pozzolanic materials. Undensified and densified silica fume, ASTM class F and class C fly ash, and metakaolin were chosen as well-known pozzolanic materials, and bentonite powder, ceramic powder obtained from wash basin, and waste glass wool, which can possibly possess pozzolanic property, were chosen for comparison. Drop in electrical conductivity at $40^{\circ}C$ saturated lime solution was measured for each materials. The amount of Ca(OH)2 decomposed from cement paste at $450{\sim}500^{\circ}C$ was also measured to evaluate pozzolanic activity. The 28 day compressive strength were used to observe the mechanical property enhanced by incorporation of various waste materials. According to the experimental results, using "difference between maximum conductivity value and conductivity value at 4 hour" was found to be a reasonable approach to determine pozzolanic activity of a material. Pozzolanic activity measured using electrical conductivity correlates very well with that measured using the amount of Ca(OH)2 remained in the cement paste. Relatively good agreement was also found with electrical conductivity and 28 day compressive strength. It was found that electrical conductivity measurement can be used to evaluate pozzolanic activity of unknown materials.