• Molecular & Cellular Toxicology
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• v.1 no.3
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• pp.157-163
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• 2005

Because of their widespread occurrence and substantial biological activity, halogenated aromatic hydrocarbons are one of the important classes of contaminants in the environment. We have performed comparative molecular field analysis (CoMFA) on structurally diverse ligands of Ah (dioxin) receptor to explore the physico-chemical requirements for binding. All CoMFA models have given $q^{2}$ value of more than 0.5 and $r^{2}$ value of more than 0.83. The predictive ability of the models was validated by an external test set, which gave satisfactory predictive $r^{2}$ values. Best predictions were obtained with CoMFA model of combined modified training set ($q^{2}=0.631,\;r^{2}=0.900$), giving predictive residual value = 0.002 log unit for the test compound. We have suggested a model comprises of four structurally different compounds, which offers a good predictability for various ligands. Our QSAR model is consistent with all previously established QSAR models with less structurally diverse ligands. The implications of the CoMFA/QSAR model presented herein are explored with respect to quantitative hazard identification of potential toxicants.

• The Korea Journal of Herbology
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• v.20 no.4
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• pp.133-140
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• 2005

Objectives : We have been used many herbal medicines after processing to improve the effect, decrease toxicity and side-effect, and change property. We have studied the physico-chemical change and HPLC pattern of Morindae Radix by means of processing method. Methods : This study was investigated the contents of loss on drying, residue on ignition, residue on acid insoluble ignition, 50% ethanol extract and HPLC pattern of Morindae Radix(Morinda officinalis How.) by processed and non-processed. We have conducted Morindae Radix and Damnacanthi Radix which is circulated in herbal medicine market by forgery. Processed Morindae Radix was prepared by heating of added to salt(SP), liquor(LP) and Glycyrrhizae Radix solution(GP) for 20-40 minutes. Results and Conclusions : From this analysis, we found that the content of 50% ethanol extract was increased by processing method. And we were detected distinguishable marker of processed and non-processed from Morindae Radix(Morinda officinalis How.) by HPLC pattern analysis.

• Journal of Environmental Health Sciences
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• v.22 no.2
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• pp.83-89
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• 1996

In order to evaluate the air quality, dry and wet deposition samples were collected by deposit containers during four months in Inchon area. The samples were analyzed for its solid composition and trace elements(Ca, Cd, Cu, Fe, Mn, Ni, Pb, Zn). The main results are summarized below 1. The amounts of dry and wet deposition in Inchon area were 1.06~3.14 ton/$km^2$/month, and affected by the rainfall and suspended yellow sand. 2. Through the analysis of solid balance, we found that 50% of total solids(TS) was fixed suspend ed solids(FSS), 25% was fixed dissolved solids(FDS), and each of volatile suspended solids(VSS) and volatile dissolved solids(VDS) accounted for 12.5%. 3. The amounts collected by sampler for trace elements were 938 ~ 2,765 $\mu g$ calcium/10days sampler, 0.2 ~ 90.4 $\mu g$ cadmium/10days/sampler, 26 ~ 298 $\mu g$ copper/10days/sampler, 928 ~ 3,939 $\mu g$ iron/10days/sampler, 50 ~ 202 $\mu g$ manganese/10days/sampler, 4 ~ 37 $\mu g$ nickel/10days/sampler, 52 ~ 406 $\mu g$ lead/10days/sampler, and 97 ~ 1,317 $\mu g$ zinc/10days/sampler, respectively. 4. Using the manganese analysis, it was found that 76.1% of TS was from soil.

• 한국해양학회지
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• v.22 no.1
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• pp.34-42
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• 1987

Canonical correlation analysis was applied on phytoplankton species and associated physico-chemical environmental factors of the surface mixed-later in the southwestern waters of the East Sea (Sea of Japan), Korea. Water temperature was the most significant environmental factor for the distribution of phytoplandton species among the seven factors examined in spring, and salinity in autumn. The importance of these two environmental factors was discussed with the seasonal variations of the hydrographical regime. Kuroshio indicators' and two protoperidinium species were positively associated with high water temperatures and high salinity. Small pennate diatoms and silicoflagellates seem to prefer lower temperatures, and they might compete each other for silicate nutrient resulting in lower K value in silicoflagellate species than in small diatoms. A nitrogen fixing blue-green alga, Oscillatoria erythraea, was found to be positively associated with phosphate concentration.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.315-315
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• 2009

Component analysis and physico-chemical properties of wood and rice hull vinegars were conducted in order to promote the utilization of these environment-friendly materials. Results showed that wood vinegar had higher specific gravity (2.5) and tar content (0.3%), but lower acid content (1.0%) than rice hull vinegar (1.7, 0.05% and 4.4%, respectively). GC-MS component analysis revealed that rice vinegar had higher phenol content (34%) than wood vinegar (11.49%). Acetic acid and propionic acid were also higher in rice hull vinegar. On the contrary, wood vinegar had higher Furancarboxyl aldehyde content (41.6%) than rice hull vinegar (0.67%). Thus, different results in DPPH radical electron donating-abilities were obtained due to different percent composition of each vinegar.

• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.385-392
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• 2021

In this study, impact of Co proportion and calcination temperature of ceria on the Co/CeO₂ was analyzed by comparing nitrogen monoxide oxidation performance of various catalysts and their physico-chemical properties. The structural properties of each catalyst were studied by XRD and BET analysis, and the surface crystal states of cobalt were proposed according to the surface density. Oxidation states of elements were observed through Raman and XPS analysis, and the relationship between typical oxidation states and nitrogen monoxide oxidation performance was designed. Through H₂-TPR, oxygen-transferring capacity due to changes in the characteristics of catalysts were identified, and activation sites (Co³⁺) for oxidation were suggested.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.57-62
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• 1978

The morphology and chemical properties of bracken (Pteridium aquilinum) root starch were investigated. The starch granules were mainly sphere and cocoon with the diameter of $5-12\mu$. Polarized micrograph indicated that the starch granule had a hilum at the center of granule, showing a crossed-birefringence. X-ray diffraction pattern demonstrated that the granules showed B-type. The density of the starch was 1.49 and the amylose content was 22%. The ferricyanide number and alkali number were 0.292 and 11.03, respectively. Proximate analysis showed that the starch contained 0.52% lipid, 0.63% ash and 150ppm phosphorus of which over 80% were found in the amylopectin fraction. The iodine affinity and molecular weight of amylose were 16.1 and 83,000 respectively. The degree of branching and glucose units per segment of amylopectin were 3.7% and 27, respectively.

• Korean Journal of Medicinal Crop Science
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• v.23 no.6
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• pp.454-459
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• 2015

Background : The major compounds of Angelica species are decursin, decursinol angelate, nodakenin, umbelliferone and ${\beta}$-sitosterol, which act anti-inflammatories, reduce pains, protect the liver and enhance the immune system. This study investigated the chemical compositions, minerals, metals, sugars and overall amino acid composition in Angelica gigas Nakai. Methods and Results : Powder of Angelica roots smaller than 30 mesh were used. Physico-chemical analysis revealed the presence of carbohydrates (62.0%), crude proteins (13.9%), moisture (11.4%), crude fats (7.3%) and ash (5.4%). Results showed that potassium was present in the highest amount (1,859 ppm), followed by magnesium (214.5 ppm), calcium (147.3 ppm) and sodium (6.0 ppm). Free sugar profiles showed the presence of sucrose (29.3 g/100 g). The total amino acids concentrations was 9,752 mg/100 g, the most common and dominant amino acids were arginine (2,181 mg/100 g), glutamic acid (1,212 mg/100 g) and aspartic acid (834 mg/100 g). The total free amino acids contents was 1,476 mg/100 g, in which the most common amino acid were arginine (932 mg/100 g), glutamic acid (127 mg/100 g), and ${\gamma}$-aminobutyric acid (80.4 mg/100 g). The fatty acid composition of A. gigas showed a higher concentration of unsaturated fatty acids such as linoleic acid (443.9 mg/100 g) and palmitic acid (181.3 mg/100 g) according to gas chromatography. Conclusions : These results showed that Angelica roots can be used in various fields of foods and medicines, and in the preparation of cosmetics.

• Journal of Life Science
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• v.25 no.10
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• pp.1139-1147
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• 2015

This study was conducted to evaluate the effects of injection of red wine on physico-chemical characteristics of pork loin ham during cold storage. The pork loin hams were manufactured by injection of red wine as Control (0%), T1 (3%), T2 (6%), T3 (9%), and were analyzed, while stored at 10±1℃ for 4 weeks, respectively. As a result of the injection of red wine, the pH values of pork loin ham were reduced, whereas WHC values were increased compared to the control (p<0.05). However, there was no significant difference in cooking loss. In meat color, as injection of red wine increased, the lightness values were reduced, and redness values were increased during 4 weeks. In texture profile analysis, values in shear force, brittleness, gumminess and adhesiveness were increased as red wine injection increased (p<0.05). But, injection of red wine reduced the VBN values until 2 weeks. Treatment groups with more than 3% red wine showed lower TMC values than control until 3 weeks (p<0.05), whereas Lactobacillus counts were significantly increased by injection of red wine since 2 weeks. In conclusion, red wines showed the effect of increasing the quality characteristics related to physical and storage in pork loin ham during cold storage, and proper injection level was 3% when pork loin ham processed.

• The Korean Journal of Ecology
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• v.25 no.5
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• pp.305-313
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• 2002

The physico-chemical characteristics of water and sediment, and structures of vegetation of the vascular hydrophytes were investigated in the West Nakdong River. Water quality was eutrophic according to the mean values and the ranges of water properties such as pH, DO, BOD, chlorophyll a, total nitrogen and phosphate, and other nutrients. A few cases were hypereutrophic for chlorophyll a level in summer. Soil reaction was weak acid. Composition of sediment was mainly sand except in SI(Sinan chideung) of which was mainly clay, and SU(Suan chideung) of which was mainly silt. Flora of vascular hydrophyte had 26 species and 1 variety comprising 16 families. Trapa japonica was dominant species in the sites of DU(Dunchido), GA(Garak chideung) and SU. Nymphoides peltata and Hydrocharis dubia dominated in DA and SI, respectively. Species diversity and evenness were relatively high in SI and SU but dominance was high in DA. After June, water lettuce(Pistia stratiotes) and water hyacinth(Eichhornia crassipes) were flowed from tributary to the river. Standing crop of macrohydrophytes was high in DA from April to August, but it showed maximum standing crop (445g·dw/㎡) in DU after disturbance by explosive growth of exotic plants in October. In comparison with those in 1985, total productivities in DU and GA decreased to 33.5%, and the reduction ratio of dominant species, Trapa japonica was 56.7%. Najas marina, N. minor, Myriophyllum spicatum and Nymphoides indica have disappeared ever since the Nakdong barrage was constructed in the Nakdong river. They were divided into three groups (GA-SU-DU, DA, SI) by cluster analysis. Introduction of the exotic species in this river caused decreasing of endemic plants including endangered species Euryale ferox and rare species Hydocharis dubia, and food plants for waterfowl such as Trapa japonica, Vallisneria asiatica and Potamogeton crispus.