• Journal of Plant Biology
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• v.26 no.2
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• pp.53-71
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• 1983

Physicochemical properties of soil, mineral cyclings, production of plants, and relationship between sodium(Na) content and progresses of plant communities were studied in a coastal salt marsh in Incheon. Contents of Na, available phosphorus(A-P) and value of electric conductivity of soil decreased in order of Salicornia herbacea, Limonium tetragonum, Phragmites communis and Zoysia sinica communities, but contents of organic matter, total nitrogen(T-N) and calcium(Ca) of soil were vice versa. Specise diversity index decreased with increase of Na content of soil with correlation coefficient of -0.82. The aboveground biomass of plant communities were 2,981 g.dw/$m^2$ in P. communis, 1,471 g.dw/$m^2$ in Z. sinica, 189g.dw/$m^2$ in S. herbacea and 71 g.dw/$m^2$ L. tetragonum, respectively. Seasonal changes of contents of inorganic nutrients per unit land area coincided with those of biomass of plant communities, however, the maximum contents of K occured earlier than the maximum biomass. Amounts of inorganic nutrients absorbed by plant were directly proportion to its biomass and it was true to reverse in restored amounts of them to soil. In turnover times of nutrients of the communities, it took the shortest time for P but the longest for Ca and P. communis community took the shortest but L. tetragonum the longest. For example, in P. communis turover time of P took one year and that of Na 1,440 years. Lack of P element, therefore, was expected in this study area.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.08a
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• pp.98-102
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• 2003

$Ba_2NaNb_5O_{15}$, hereafter BNN, thin films are attractive candidates for nonvolatile memory and electro-optic devices. In the present work, thin films that have different contents of Ba, Na and Nb have been prepared by H-MOD technique on silicon and Pt substrates. XRD and SEM were used to investigate the phase evolution behavior and the microstructure of the films. It was found that the films of about 450nm thick were crack-free and uniform in microstructure. Nb content strongly influenced the phase formation of the films, where low temperature phase was always formed at the stoichiometric BNN composition. However, the amount of low temperature phase decreased with the increase of excess Nb content, and the single phase (orthorhombic tungsten bronze structure) BNN thin film was obtained at the temperature as low as $750^{\circ}C$ for samples with excess niobium. From this study, the sub-solidus phase diagram below $850^{\circ}C$ for $BaO-Na_2O-Nb_2O_5$ ternary system is proposed.

• Journal of the Korean Ceramic Society
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• v.56 no.5
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• pp.468-473
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• 2019

This study focused on manufacturing an inorganic insulation material set with various amounts of calcium-sulfoaluminate (CSA) (hauyne) content for enhancing both workability (demolding, handling) and the high thermal insulating property. To carry out the experiment, the amounts of CSA utilized were 5%, 10%, 15%, and 20%, with anhydrous gypsum added in equal proportion to produce a stable formation. As the content of CSA increased, a sinking phenomenon occurred because of the hydration reaction from the slurry, so it was difficult to utilize a retarder normally used in the cement manufacturing process. However, an RCOOM surfactant was able to solve the local clumping problem from cement and CSA and obtain a rapid retarding effect, so it was included in this process at 0.3%. Furthermore, the cement fineness was not 7000 ㎠/g but rather 3300 ~ 4000 ㎠/g to prevent a rapid temperature increase in the slurry. The specific gravity of the sample manufactured with 20% CSA was approximately 0.11 g/㎤, and its thermal conductivity was 0.041 W/m·K, providing an excellent insulating property.

• Korean journal of food and cookery science
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• v.25 no.4
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• pp.421-426
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• 2009

The objective of this study was to evaluate the antioxidant and physiological The objective of this study was to evaluate the antioxidant and physiological activities of organic and inorganic coffee based on flavonoid composition. Organic and inorganic coffee varieties were prepared with Brazil arabica bean and Columbia arabica bean, respectively. Color values (Lightness, redness, and yellowness), mineral contents, total phenol content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, individual flavonoids, and sensory characteristics were then measured in the espresso of each coffee bean. The pH, Brix, and color difference between organic coffee and inorgainc coffee did not correlate with the harvest method. Coffee varieties were more influential on physiological properties, and were markedly more influential than the mineral content. Total phenolics had a higher correlation with DPPH radical scavenging activity ($r^2$=0.832). Depending on the harvesting method, significant differences (p<0.05) were shown in aroma, color, and overall acceptability in sensory evaluation.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.1066-1072
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• 2010

In this study, the effects of replacing inorganic copper, zinc and manganese with different levels of organic complexes of the same trace minerals on the lipid peroxidation and antioxidant defense systems in broilers were investigated. Two-hundred Ross-308 one-day-old broiler chickens were placed on controlled diets until 42 d of age. The experimental animals were divided into four groups comprising three experimental groups and one control group, each consisting of 50 chickens. All groups were also divided into five subgroups each containing 10 broiler chicks. The mineral content of the control group diet was controlled using a standard inorganic mineral premix with supplement levels and sources of trace minerals typical of commercial broiler diets according to the National Research Council (NRC) (containing 8 mg Cu as $CuSO_4$, 40 mg Zn as $ZnSO_4$, and 60 mg Mn as MnO, per kg). In the experimental diets, mineral premix was also comprised of inorganic formulations, except for those of Cu, Zn and Mn. Organically-complexed Cu, Zn, and Mn were separately added to the basal diet at 1/3 (L1), 2/3 (L2) and 3/3 (L3) levels with respect to the NRC recommendation, as Bioplex $Cu^{TM}$, Bioplex $Zn^{TM}$, Bioplex $Mn^{TM}$. At the end of the trial, the plasma Zn level significantly increased when the plasma Cu level significantly decreased (p<0.05) in chickens fed at 2/3 and 3/3 levels of organically complexed minerals. The liver trace mineral concentrations were significantly higher in chickens fed inorganic trace minerals in comparison to those fed organically-complexed minerals. The plasma malondialdehyde (MDA) level of experimental chickens was decreased in groups receiving levels of organic Cu, Zn and Mn in comparison to those fed inorganic forms (p<0.01). The erythrocyte superoxide dismutase (SOD) activity was higher in all groups receiving the organic mineral supplements in comparison to those fed inorganic forms (p<0.01). No differences were observed on either the erythrocyte catalase (CAT) activity or the plasma ceruloplasmin (Cp) levels, and the liver MDA levels and liver CAT and SOD activities in any of the groups that received the organic supplements of Cu, Zn, and Mn. It was concluded that supplementation of lower levels of organically-complexed copper, zinc, and manganese instead of their inorganic forms in diets had no negative effects on the antioxidant defense system in broilers.

• Journal of Ecology and Environment
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• v.37 no.3
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• pp.131-137
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• 2014

To investigate the solute pattern of salt marsh plants in Suncheon Bay in Korea, plants and soil samples were collected at three sites from July to September 2011. The soil pH around the investigated species was weakly alkaline, 6.9-8.1. The total ion and Cl- content of site 1 gradually increased, while those of site 2 and site 3 were lowest in August and highest in September. The exchangeable $Ca^{2+}$, $Mg^{2+}$ and $K^+$ in the soil were relatively constant during the study period, but the soil exchangeable $Na^+$ content was variable. Carex scabrifolia and Phragmites communis had constant leaf water content and very high concentrations of soluble carbohydrates during the study period. However, Suaeda malacosperma and S. japonica had high leaf water content and constant very low soluble carbohydrate concentrations. Carex scabrifolia accumulated similar amounts of $Na^+$ and $K^+$ ions in its leaves. Phragmites communis contained a high concentration of $K^+$ ions. Suada japonica and S. malacosperma had more $Na^+$ and $Cl^-$ ions than $K^+$ ions in their leaves. Suaeda japonica had higher levels of glycine betaine in its leaves under saline conditions than C. scabrifolia and P. communis. Consequently, the physiological characteristics of salt marsh chenopodiaceous plants (S. japonica and S. malacosperma) were the high storage capacity for inorganic ions (especially alkali cations and chloride) and accumulation of glycine betaine, but monocotyledonous plant species (C. scabrifolia and P. communis) showed high $K^+$concentrations, efficient regulation of ionic uptake, and accumulation of soluble carbohydrates. These characteristics might enable salt marsh plants to grow in saline habitats.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1073-1080
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• 2011

In order to investigate and generalize the effects of carbon and nitrogen sources on the growth of and lipid production in Chlorella sp. 227, several nutritional combinations consisting of different carbon and nitrogen sources and concentrations were given to the media for cultivation of Chlorella sp. 227, respectively. The growth rate and lipid content were affected largely by concentration rather than by sources. The maximum specific growth was negatively affected by low concentrations of carbon and nitrogen. There is a maximum allowable inorganic carbon concentration (less than 500~1,000 mM bicarbonate) in autotrophic culture, but the maximum lipid content per gram dry cell weight (g DCW) was little affected by the concentration of inorganic carbon within the concentration. The lipid content per g DCW was increased when the microalga was cultured with the addition of glucose and bicarbonate (mixotrophic) at a fixed nitrogen concentration and with the lowest nitrogen concentration (0.2 mM), relatively. Considering that lipid contents per g DCW increased in those conditions, it suggests that a high ratio of carbon to nitrogen in culture media promotes lipid accumulation in the cells. Interestingly, a significant increase of the oleic acid amount to total fatty acids was observed in those conditions. These results showed the possibility to induce lipid production of high quality and content per g DCW by modifying the cultivation conditions.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.701-705
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• 2021

Although the breed protection rights of Jangsaemi garlic were registered in 2012, the cultivation area was not large and no related papers were found, so this study was conducted. Potassium was the highest inorganic content of Jangsaemi garlic, followed by nitrogen, sulfur, and phosphorus. Allin and allicin were also present at 9.73±0.97 and 1.65±0.15 mg/g, respectively. The solid content was 7.90±0.00°Bx, and the reducing sugar was 33.42±1.79 mg GE/g. The total phenol and flavonoid contents were 80.35±2.67 mg GAE/100 g and 33.80±2.17 mg QE/100 g, respectively. The antibacterial activity of Jangsaemi garlic was higher in gram-positive bacteria than in gram-negative bacteria, especially Staphylococcus epidermidis and Micrococcus luteus. The results of these studies are expected to provide useful information for farmers growing Jangsaemi garlic in the future.

• Analytical Science and Technology
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• v.6 no.3
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• pp.297-305
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• 1993

Generally, it is difficult to analyze cast iron samples with spark discharge emission spectrometry since the content of carbon in these samples is high as a few percent. The cast iron samples were analyzed with the developed glow discharge emission spectrometer composed of glow discharge emission source and polychromator. The discharge condition of glow discharge lamp(GDL) has been optimized by variation of Ar gas pressure, discharge voltage and discharge time. Under the optimum conditions obtained in this work, relationships between the measured emission intensities and concentration of two types of cast iron standard samples(BAS, LECO) were investigated. Most of elements(Mn, Si, P, S etc.) showed the good linearity in one calibration curve. And the carbon showed slightly the systematic difference according to the type of standard samples.

• Journal of the Korean Wood Science and Technology
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• v.48 no.6
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• pp.896-906
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• 2020

Wood deterioration experiments were carried out for 6 months in an intertidal zone of South Korea to monitor the changes in the chemical properties of two types of species, Korean red pine and sawtooth oak. The results of FT-IR spectra and XRD patterns have shown that the chemical properties of the wood did not change significantly during the 6-month burial period. However, the brightness of the surface decreased after burial; the value of the sawtooth oak sample was lower than that of the Korean red pine sample owing to an accumulation of inorganic compounds in cell lumen as observed by ICP analysis. Among the inorganic compounds, sodium and sulfur concentrations increased significantly over the burial period compared with the control. Further, the maximum moisture content decreased from 199% to 136% in the Korean red pine and 62% to 60% for the sawtooth oak. Nevertheless, the major chemical composition of both the wood species did not change significantly during the 6-month burial period, whereas, the crystallinity decreased with an increasing burial period owing to an accumulation of inorganic compounds in the lumen.