• The Journal of Engineering Geology
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• v.7 no.2
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• pp.127-137
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• 1997

Bentonites that are used currently for the civil engineering puppose in our country were investigated to reveal their physico-chemical properties such as viscosity, swelling volume, cation exchange capacity (CEC) and chemical composition, and to compare the content of their constituting minerals and their characteristics using the X-ray diffraction and infrared spectrum methods. The content of montmorillonite in the hentonites ranges from 50 to 79%. As the content of montmorillonite in the hentonites increases, the viscosity, swelling volume, water content, methylene blue adsorption, CEC, and the amount of clay-size particles tend to increase in general. Because these properties also show good correlation within them, the results can he used to infer the characteristics of hentonites indirectly. However, a few samples do not show this correlation hetween the properties. This is probably due to the characteristics of constituting minerals of raw ore and manufacturing process. A saraple with lowest content of rnontrnofiiionite was shown to be inferior in the physico-chemical properties that are needed for the civil engineering-purpose bentonites.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.6 s.107
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• pp.95-102
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• 2005

This study was carried out to find out the heavy metal contents and the physico-chemical properties for the improvement of dredged soils which widely exist in lowlands of Korea. At first all the average heavy metal contents were close to background level and were much lower than concern level of the Soil Environment Conservation Act of Korea. And the results of physical analyses of soils showed on the average $2.46\~2.74 Mg/m^3$ in Particle density, $0.45\~2.45 kg/kg$ in soil water contents, $0.34\~0.90 Mg/m^3$ in bulk density, $0.67\~0.87m^3/m^3$ in porosity, $2.18\times10^{-5}\~1.20\times10^{-8} m/s$ in saturated hydraulic conductivity, R0.12\~0.65 m^3/m^3$ in available water contents. Finally the results of chemical analyses of soils showed on the average $6.5\~8.2\;in\; pH,\;5\~48 g/kg\;in\; OM,\;0.48\~4.51g/kg\;in\;T-N,\;19\~25mg/kg$ in available phosphate, $0.28\~11.80 dS/m\;in\;EC,\;8.7\~38.1cmol/kg$ in CEC, respectively Accordingly, the physicochemical properties of soils ought to be analyzed accurately before dredging for effective using of dredged soils. And it will be more effective, if the dredged soils are used with proper balance among each content of components with consideration to the physicochemical properties of common soils.

• Food Science of Animal Resources
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• v.21 no.3
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• pp.208-214
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• 2001

This study was conducted to investigate the influence of dietary oriental medicine refuse(OMR) and mugwort powder on physico-chemical characteristics of Korean Native Pork(KNP). KNP were randomly assigned to one of the three dietary treatments : 1) control (commercial feed) 2) T1 (commercial fed supplemented with 10% OMR powder) 3) T2 (commercial feed with 10% mugwort powder). 15 heads(♂) were feed one of the experimental diets for 5 months and slaughtered. In the proximate composition, moisture content showed slightly high in the T1, however, fat content were tended to be high in the control. The heating loss, shear value, WHC (water holding capacity) were not significantly between control and the treatments group. The T1 showed the lowest pH among treatments (P<0.05). In sensory evaluation, juiciness and tenderness of T1 and T2 were higher compared with that of control. Hunter a* did not show any difference among the treatments group. But Hunter L*, b* in treatment group(T1, T2) were higher than that of the control. Oleic acid, linoleic acid and unsaturated fatty acid contents of T1 and T2 were higher than the control. The total amino acid of the control, T1 and T2 were 18.290, 18.177 and 18.942mg%, respectively.

• Korean journal of food and cookery science
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• v.32 no.2
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• pp.204-210
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• 2016

Purpose: This study analyzed and compared the physico-chemical and affective properties between mackerels cooked by an electric pan and under superheated steam. Methods: Mackerel were cooked by an electric pan ($95^{\circ}C$) for 10 min and mackerel cooked under superheated steam ($250^{\circ}C$) for 5 min to be internal temperatures of $75{\pm}5^{\circ}C$ and tests to measure proximate composition, color values, texture profiles, microorganism counts and sensory acceptance were performed. Results: The moisture contents were 60.30% and 73.81% in mackerels cooked by electric pan and under superheated steam, respectively. The rate of weight loss in mackerel cooked by electric pan was 39%, whereas it was 29% in mackerel cooked under superheated steam. Mackerel cooked under superheated steam exhibited more yellowness, higher springiness, cohesiveness, gumminess, chewiness, and resilience with more acceptable preferences (appearance, odor, taste, and texture) compared to the mackerel cooked by electric pan. Conclusion: The application of superheated steam technology to fish products could reduce the cooking time and nutritional loss. Also, it could produce highly preferred fish products compared to that prepared by conventional electric pan.

• Geomechanics and Engineering
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• v.1 no.4
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• pp.291-306
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• 2009

One-dimensional soil-column studies were carried out to understand the interaction of three industrial effluents namely amino acid ('highly acidic'), surfactant ('highly organic') and pharmaceutical ('organic and toxic') on the physicochemical behavior, index properties and shear strength of bentonite due to artificial contamination extending to nearly 300 days. Changes in inorganic and organic pollutants present in the effluents due to the interaction of the above effluents and soil were assessed to understand the physico-chemical behaviour. Batch and continuous modes of operation, 8 hrs and 16 hrs Hydraulic Retention Time [HRT] and 25%, 50% concentrations of effluents, were the parameters considered. Amino acid, surfactant and pharmaceutical effluents have shown a high variation in pH (7 to 8) after artificial contamination on bentonite that is their original characteristics of the above effluents have been completely reversed. Further, it is found that the shear strength of bentonite has reduced by about 20%, and with respect to liquid limit and plastic limit shows an increasing trend with time within the period of contamination.

• Journal of Ginseng Research
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• v.37 no.1
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• pp.124-134
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• 2013

The authentication of the physico-chemical properties of ginsenosides reference materials as well as qualitative and quantitative batch analytical data based on validated analytical procedures is a prerequisite for certifying good manufacturing practice (GMP). Ginsenoside Rb1 and Rg1, representing protopanaxadiol and protopanaxatriol ginsenosides, respectively, are accepted as marker substances in quality control standards worldwide. However, the current analytical methods for these two compounds recommended by Korean, Chinese, European, and Japanese pharmacopoeia do not apply to red ginseng preparations, particularly the extract, because of the relatively low content of the two agents in red ginseng compared to white ginseng. In manufacturing fresh ginseng into red ginseng products, ginseng roots are exposed to a high temperature for many hours, and the naturally occurring ginsenoside Rb1 and Rg1 are converted to artifact ginsenosides such as Rg3, Rg5, Rh1, and Rh2 during the heating process. The analysis of ginsenosides in commercially available ginseng products in Korea led us to propose the inclusion of the (20S)- and (20R)-ginsenoside Rg3, including ginsenoside Rb1 and Rg1, as additional reference materials for ginseng preparations. (20S)- and (20R)-ginsenoside Rg3 were isolated by Diaion HP-20 adsorption chromatography, silica gel flash chromatography, recrystallization, and preparative HPLC. HPLC fractions corresponding to those two ginsenosides were recrystallized in appropriate solvents for the analysis of physico-chemical properties. Documentation of those isolated ginsenosides was achieved according to the method proposed by Gaedcke and Steinhoff. The ginsenosides were subjected to analyses of their general characteristics, identification, purity, content quantification, and mass balance tests. The isolated ginsenosides showed 100% purity when determined by the three HPLC systems. Also, the water content was found to be 0.534% for (20S)-Rg3 and 0.920% for (20R)-Rg3, meaning that the net mass balances for (20S)-Rg3 and (20R)-Rg3 were 99.466% and 99.080%, respectively. From these results, we could assess and propose a full spectrum of physico-chemical properties of (20S)- and (20R)-ginsenoside Rg3 as standard reference materials for GMP-based quality control.

• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.239-247
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• 2022

The physico-chemical properties of agricultural soil are factors that affect crop productivity and soil fertility. In Korea, agricultural environment change surveys have been conducted every four years since 1999. The purpose of this study is to investigate the status and changes in the physico-chemical properties of agricultural soil in Chungcheongnam-do. Samples were collected from the exact location of the aforementioned environment survey, and environmental variables (land use, type of crop cultivated) were investigated in relation to the samples. Soil collection was conducted using a core sampler and a single gouge auger. The bulk density of the soil generally increased up to a depth of sampling of 40 cm but decreased thereafter to a depth of 60 cm. Additionally, the bulk density was highest in the upland soil case and stood at 1.59 g·cm^-3, while the lowest value of 1.52 g·cm^-3 was obtained from orchard soil samples. Conversely, the porosity and moisture gradually decreased at soil depths of 0 - 40 cm and increased at depths of 40 - 60 cm. Most of the soil chemical properties generally decreased with an increase the soil depth from 0 to 70 cm, but electrical conductivity (EC) increased up to a depth of 40 cm. Therefore, it is judged that it is necessary to lower the bulk density by supplying organic matter for agricultural land in Chungcheongnam-do.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.2
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• pp.103-108
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• 1995

Antibiotic and physico-chemical properties of an active compound from actinomycetes isolate G-37, of which the culture filtrate had an inhibitory effect against tobacco mosaic virus(W) infection, were examined. The active compound, which was purified by ethylacetate extraction, silica gel column chromatography, preparative thin layer chromatography, and high performance liquid chromatography, showed strong antibacterial activities especially against Gram-positive bacteria including Bacillus subtillis, Sarcina lutea and Staphylococcus aureus. From the IH-NMR, FAB/RfS, UV spectral data, and physicochemical properties, the active compound of G-37 appears to belong to a peptide antibiotic group. Among the known peptide antibiotics in the antibiotic group, No. 280, A-30912, and Taitomycin showed molecular weights and ultra violet spectrum similar to those of the active compound from G-37, but was not identical to the compound, which suggests that it may be a new peptide antibiotics.

• Journal of the Mineralogical Society of Korea
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• v.1 no.1
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• pp.32-39
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• 1988

The effect of soil forming factors on the pedogenesis of basaltic volcanic ash soils and the influence of allophane material on soil properties have been investigated on 5 chronosequence soils situated from at the near sea coast up to the foot slope of Mt. Halla in Jeju Island. Time seems to be the important soil forming factor which today differentiates soil of the Island. Songag and Donghong soils developed in lower elevations are older and somewhat less influenced by ash shower. However, soils developed at higher elevations, Pyeongdae and Heugag, are rather younger and strongly influence by the ash. It is also proved that the parent materials are very heterogeneous. They mainly are basaltic with some contamination of acidic volcanic ashes and continental aeolian deposits where a considerable amount of quartz encountered in most soils studied. Many physico-chemical properties of soil, such NaF pH, phosphate sorption power, pH and extractable acidity are parameters to differentiate andepts and non-andeptic soils.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.212-217
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• 2002

This study was conducted to investigate the influence of dietary mugwort on physico-chemical characteristics and processing characteristics in meat sample of chicken meat. Broilers were randomly assigned to one of four dietary treatments: 1) Control(commercial feed) 2) T1(commercial feed supplemented with 1% mugwort) 3) T2(commercial feed with 3% mugwort) and 4)T3(commercial feed with 5% mugwort). They were fed one of the experimental diets for five weeks and slaughtered. After that, the meat samples were vacuum packaged and stored at 4${\pm}$1$^{\circ}C$. The physico-chemical characteristics and processing characteristics were analyzed for meat samples stored over a period of 0, 1, 2, 3 and 4 weeks. The pH of all treatments significantly increased during the storage periods(U<0.05). The pH of the thigh was rather higher than that of the breast. The drip loss and heating loss tend to decrease in dietary mugwort group(p<0.05). The WHC(water holding capacity) of all treatment was significantly increased during storage(p<0.05). The meat color was increased during storage.