• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.400-408
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• 2003

Chloride ion inside concrete destroys the so-called passive film surrounding reinforcing bars inside concrete so that the so-called salt attack accelerates corrosion which is the most critical factor for durability as well as structural safety of reinforced concrete structures. Recently, as a solution of the salt attack, the ground granulated blast-furnace slag(GGBFS) have been used as binder or blended cement more extensively. In this paper, characteristics of chloride ion diffusion for the GGBFS concrete, which is known to possess better resistance to damage due to the chloride ion penetration than ordinary portland cement(OPC) concrete possesses, are analyzed and a chloride ion diffusion model for the GGBFS concrete is proposed by modifying an existing diffusion model for the OPC concrete. The proposed model is verified by comparing diffusion analysis results using the model accelerated chloride penetration test results for concrete specimens as well as field test results for an RC bridge pier. Then, an optimal resistance condition to chloride penetration for the GGBFS concrete is obtained according to degrees of fineness and replacement ratios of the GGBFS concrete. The result shows that the GGBFS concrete has better resistance to chloride ion penetration than OPC concrete has and the resistance is more affected by the replacement ratio than the degree of fineness of the GGBFS.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.79-85
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• 2002

Ecological characteristics of microorganisms in tideland soils were studied by investigation of microbial diversity and population. Twenty soil samples were taken at surface, 10, 20 and 30 cm depth each. Bacteria, actinomycetes and fungi were isolated on each selective isolation medium containing different concentration of NaCl. Actinomycetes were the most isolated from soil samples taken at 10 cm depth and isolated by humic acid-vitamin (HV) medium without sea water or salt. Twenty nine strains of actinomycetes were isolated at surface soil and 74, 39, 37 strains were at 10, 20, and 30 cm depth, respectively. All these isolates were analysed and grouped by random amplified polymorphic DNA (RAPD)-PCR analysis. Many of the isolates were clustered into Microtetraspora and Pseudonocardia. Fungal isolates were highly distributed at the surface soil and isolated well on potato dextrose agar (PDA) medium with sea water. Bacterial isolates were higly distributed at surface soil and isolated well by nutrient medium without sea water or salt. Soil samples taken at 10 cm depth showed the highest microbial diversity and population.

• Journal of Sensor Science and Technology
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• v.5 no.3
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• pp.93-100
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• 1996

Polycrystalline $Sr_{2}(Ta_{1-x}Nbx)_{2}O_{7}$ and $La_{2}Ti_{2}O_{7}$ ceramics having very high Curie temperatures were synthesized by the conventional oxide mixing method (CON) and the molten salt synthesis method (MSS). Physical characteristics and phase relationship of calcined powders, as well as the sintering behavior, the grain-orientation and dielectric properties of sintered ceramics were investigated as a function of composition and firing temperature. The single $A_{2}B_{2}O_{7}$ phase was synthesized by using the MSS method at 100 - $150^{\circ}C$ lower temperature compared to the CON method. As Nb content increased in $Sr_{2}(Ta_{1-x}Nbx)_{2}O_{7}$ ceramics, the Curie temperature and the dielectric constant at Curie temperature were raised, and the sintering behavior and the degree of grain-orientation were also improved at the same time. The use of MSS-derived powders made it possible to lower the sintering temperature and to improve the dielectric properties of the sintering samples. However, the piezoelectric properties as well as the grain-orientation were not improved any further by the MSS route.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.107-107
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• 2017

3D bioprinting is a technology to produce complex tissue constructs through printing living cells with hydrogel in a layer-by-layer process. To produce more stable 3D cell-laden structures, various materials have been developed such as alginate, fibrin and gelatin. However, most of these hydrogels are chemically bound using crosslinkers which can cause some problems in cytotoxicity and cell viability. On the other hand, thermosensitive hydrogels are physically cross-linked by non-covalent interaction without crosslinker, facilitating stable cytotoxicity and cell viability. The examples of currently reported thermosensitive hydrogels are poly(ethylene glycol)/poly(propylene glycol)/poly(ethylene glycol) (PEG-PPG-PEG) and poly(ethylene glycol)/poly(lactic acid-co-glycolic acid) (PEG/PLGA). Chitosan, which have been widely used in tissue engineering due to its biocompatibility and osteoconductivity, can be used as thermosensitive hydrogels. However, despite the many advantages, chitosan hydrogel has not yet been used as a bioink. The purpose of this study was to develop a bioink by chitosan hydrogel for 3D bioprinting and to evaluate the suitability and potential ability of the developed chitosan hydrogel as a bioink. To prepare the chitosan hydrogel solution, ${\beta}-glycerolphosphate$ solution was added to the chitosan solution at the final pH ranged from 6.9 to 7.1. Gelation time decreased exponentially with increasing temperature. Scanning electron microscopy (SEM) image showed that chitosan hydrogel had irregular porous structure. From the water soluble tetrazolium salt (WST) and live and dead assay data, it was proven that there was no significant cytotoxicity and that cells were well dispersed. The chitosan hydrogel was well printed under temperature-controlled condition, and cells were well laden inside gel. The cytotoxicity of laden cells was evaluated by live and dead assay. In conclusion, chitosan bioink can be a candidate for 3D bioprinting.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.726-731
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• 2003

The aim of this research was to identify candidate probiotic lactic bacteria among indigenous dadih lactic isolates. Dadih is an Indonesian traditional fermented milk of West Sumatra which is fermented naturally. Viability of the strain is critical in determining the capacity of lactic bacteria to induce immune stimulation as well as to colonize in the intestinal tract. Therefore, LAB are proposed to exert health promoting or probiotic effects in human, such as inhibition of pathogenic microflora, antimutagenic, and the reduction of cholesterol levels. This manuscript reports in vitro probiotic properties of indigenous dadih lactic bacteria, especially some important colonization factors in GI tract, such as lysozyme, acid and bile tolerance. Bile Salt Hydrolase (BSH) activity, spectrum of bacteriocin, and antimutagenic activity of bacterial cells were also assessed. Twenty dadih lactic isolates were screened further for their tolerance to low pH, at pH 2 and 3 as well as their bile tolerance. There were ten isolates classified as acid and bile acid tolerant, and further screened for lysozyme tolerance, BSH activity. The spectrum of bacteriocin activity of isolates was assayed using cell-free neutralized supernatants by agar spot test against variety of pathogens. Lc. lactis subsp. lactis IS-10285, IS-7386, IS-16183, IS-11857 and IS-29862, L. brevis IS-27560, IS-26958 and IS-23427, Leu.mesen.mesenteroides IS-27526, and L. casei IS-7257 each has good survival rate at low pH values and in the presence of lysozyme, and short lag time in the presence of 0.3 % oxgall. Lc. lactis subsp. lactis IS-11857 and IS-29862 each has high BHS activity, Lc. lactis subsp. lactis IS-10285 and IS-16183 each had a positive spectrum of bacteriocin activity against E. coli 3301 and Lysteria monocytogenes ATCC 19112, while L. brevis IS-26958 has high BHS activity as well as positive spectrum of bacteriocin against E. coli 3301, Lysteria monocytogenes ATCC 19112, and S. aureus IFO 3060. All of the ten dadih lactic strains performed in vitro acid and bile tolerance, indicating a possibility to reach the intestine alive, and display probiotic activities.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.105-119
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• 1976

Sucrose, glucose, starches hydrolyzates and raw starchy materials hydrolyzates were caramelized using various catalysis and the caramel products were analysed, in order to carry out the basic research for the replacement of caramel coloring. The results obtained were summarized as follows. 1. The caramel which was manufactured by sucrose syrup being pH 3.5 adjusted by sulfuric acid showed strong color intensity and hue as well as good stability in the solutions of table salt, tannin and alcohol. 2. The product caramelized from sucrose syrup being pH 9.5 adjusted by sodium carbonate showed very strong color intensity and black color component, and was quite stable in alcohol solution but not in table salt and tannin solutions. 3. The caramel products made from sucrose syrup using ammonium salts of strong acid like $NH_4Cl$ and $(NH_4)_2SO_4$ as catalyst showed strong color intensity and black color component but hazy apparence in solution of table salt, tannin and alcohol. 4. The product caramelized from glucose syrup being pH 9.5 adjusted by sodium carbonate indicated strong color intensity but weak red color component and was transparent in solution of table salt and alcohol but hazy in tannin solution. 5. In glucose caramel using $NH_4Cl$, $(NH_4)_2SO_4$, $(NH_4)_2CO_3$ and $(NH_4)_2SO_3$ as catalyst, $NH_4Cl$ plot was very weak in color intensity and insufficient in red color component but stable in solution of table salt, tannin and alcohol. In the case of $(NH_4)_2CO_3$, $(NH_4)_2SO_4$ and $(NH_4)_2SO_3$ plots, all products were strong in color intensity but little insufficient in red color component. On the stability in solutions, $(NH_4)_2SO_3$ plot was stable in two solutions expect tannin solution, $(NH_4)_2CO_3$ plot was only stable in alcohol solution and $(NH_4)_2SO_3$ plot was only stable in table salt solution. 6. When the acid hydrolyzed starch syrups without neutralization were caramelized using $(NH_4)_2SO_4$ as catalyst, the potato starch hydrolyzate caramel showed higher in color intensity being similar to its of glucose caramel than sweet potato starch hydrolyzate caramel and corn starch hydrolyzate caramel. 7. Dried sweet potato powder, dried acorns powders, the acorns (from Q. serrata THUNB and Q. acutissima CARR.) powders extracted with water for 7 days and with 50% alcohol solution for 24 hrs were hydrolyzed by sulfuric acid in autoclave at $3.5kg/cm^2$ as pressure for 60 mins, and were caramelized using $(NH_4)_2SO_4$ as catalyst. It was supposed that all of those products were poor quality on color and stability in solutions at the viewpoint of food coloring matter.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.26-37
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• 2015

Halophyte distribution pattern and area in the Suncheon-bay and Beolgyo estuary coastal wetlands were analyzed using KOMPSAT-2 landsat images were taken in 2008 and 2009, and field investigations were fulfilled for confirming the precise boundaries of individual halophyte areas. The salt-marsh vegetation in those areas can be classified mainly into two dominant communities: Suaeda japonica-dominant and Phragmites communis-dominant communities. In order to identify sedimentary characteristics, tidal-flat surface leveling and sedimentary facies analysis had been conducted. The sedimentary facies of marsh area are mostly silty clayey and clay facies with a little seasonal change and its slope is very gentle (0.0007~0.002 in gradient). Phragmites communis and Suaeda japonica communities were distributed in the mud-flat zone between 0.7 m and 1.8 m higher than MSL (mean sea level): zone of 1.1~1.8 m in the former and zone of 0.7~1.3 m in the latter. In the Suncheon-bay estuarine wetland, on the basis of 2009 distribution, Phragmites communis-dominant and Suaeda japonica-dominant communities are about $0.79km^2$ and $0.22km^2$ in distribution area, respectively. On the other hand, Bulgyo estuarine marsh shows that the distribution areas of Phragmites communis-dominant and Suaeda japonica-dominant communities are about $0.31km^2$ and 0.031km2 in distribution area, respectively. Individual 105 and 60 dominant community areas and their distribution patterns can be well defined and indicated in the Suncheon-bay and Bulgyo estuarine marshes, respectively. The distribution pattern and area of hylophyte communities analyzed in this study based on 2008/2009 satellite images would be valuable as a base of future monitoring of salt-marsh related studies in the study area which is the most important salt-marsh research site in Korea.

• The Korean Journal of Petroleum Geology
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• v.4 no.1_2 s.5
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• pp.27-39
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• 1996

In the Cretaceous, the Gulf Coast Basin evolved as a marginal sag basin. Thick clastic and carbonate sequences cover the disturbed and diapirically deformed salt layer. In the Cretaceous the salinities of the Gulf Coast Basin probably matched the Holocene Persian Gulf, as is evidenced by the widespread development of supratidal anhydrite. The major Lower Cretaceous reservoir formations are the Cotton Valley, Hosston, Travis Peak siliciclastics, and Sligo, Trinity (Pine Island, Pearsall, Glen Rose), Edwards, Georgetown/Buda carbonates. Source rocks are down-dip offshore marine shales and marls, and seals are either up-dip shales, dense limestones, or evaporites. During this period, the entire Gulf Basin was a shallow sea which to the end of Cretaceous had been rimmed to the southwest by shallow marine carbonates while fine-grained terrigengus clastics were deposited on the northern and western margins of the basin. The main Upper Cretaceous reservoir groups of the Gulf Coast, which were deposited in the period of a major sea level .rise with the resulting deep water conditions, are Woodbinefruscaloosa sands, Austin chalk and carbonates, Taylor and Navarro sandstones. Source rocks are down-dip offshore shales and seals are up-dip shales. Major trap types of the Lower and Upper Cretaceous include salt-related anticlines from low relief pillows to complex salt diapirs. Growth fault structures with rollover anticlines on downthrown fault blocks are significant Gulf Coast traps. Permeability barriers, up-dip pinch-out sand bodies, and unconformity truncations also play a key role in oil exploration from the Cretaceous Gulf Coast reservoirs. The sedimentary sequences of the major Cretaceous reseuoir rocks are a good match to the regressional phases on the global sea level cuwe, suggesting that the Cretaceous Gulf Coast sedimentary stratigraphy relatively well reflects a response to eustatic sea level change throughout its history. Thus, of the three main factors controlling sedimentation (tectonic subsidence, sediment input, and eustatic sea level change) in the Gulf Coast Basin, sea-level ranks first in the period.

• Journal of agriculture & life science
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• v.50 no.4
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• pp.91-98
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• 2016

This aim of the present study was to evaluate the effects of phosphate on the quality properties of the surimi-like materials. Surimi-like materials as a control was prepared with beef heart by three times of washing treatment. Three types of surimi-like materials were manufactured by different conditions(T1: 2% salt, T2: 1.95% salt+0.05% phosphate, T3: 1.90% salt+0.10% phosphate). The moisture content was significantly lower in T1 than the control, and T3 sample had the highest crude protein content(P<0.05). The cooking loss was significantly lower in T2 than the control, and T2 sample had the highest water-holding capacity(P<0.05). The lightness and whiteness values were significantly lower in the treatment samples compared to the control sample; whereas redness values was higher than the control(P<0.05). Beef heart surimi-like materials added with salt and phosphate had higher in texture properties in the control, and T3 sample had the highest hardness, cohesiveness, gumminess and chewiness values(P<0.05). Therefore, the addition of phosphate could increase the protein content and gel properties as well as water-holding capacity of surimi-like materials from beef heart.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.65-72
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• 2001

Four newly isolated bacteria from soil were used to manufacture microbial inoculum to compost food waste. The bacteria, GM103, V25, V31, and V35, were identified as Bacillus licheniformis, B. subtilis, B. stearothermophilius, and B, subtilis, respectively. The bacterial strains were efficient to degrade protein and starch and also able to inhibit the growth of plant pathogenic fungus Rhizopus stronifer. The GM103 showed distinct capability in degrading starch, but grow only aerobically. The other three bacterial strains. V25, V31, and V35, could grow both aerobically as well as anaerobically, in 10%(w/v) salt, at $50^{\circ}C$, and had good viability and survival rate in soil. These characteristics of the bacterial strains are very adquate in Korean food composting containing high concentration of salt, especially at home. By mixing the 4 bacterial culture broth with molasses, beet pulp, zeolite, The bacterial inoculum for food waste composting-BIOTOP-CLEAN-was made. The performance of food waste composting by the BIOTOP-CLEAN was compared with that by control(not treated) and HS(other demestic company's inoculum product for food waste composting). The maximum temperature of the food waste during the composting with the BIOTOP-CLEAN was $50^{\circ}C$, while those of the control and HS were $30^{\circ}C$ and $35^{\circ}C$, respectively. The BIOTOP-CLEAN gave the good smell and showed dark brown color, while the control gave bad smell and HS gave less bad smell. These indicates that the food waste composting by the BIOTOP-CLEAN had been well accomplished. The culture broth of V25, V31, V35 were sparyed to the plants of tomato, chinese cabbage, raddish, red pepper every month and the spraying the culture broth to these plant significantly improved the production yield of the crops, due to the control effect of the bacterial strains against the plant pathogens.