• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.733-742
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• 2000

Fundamental materialistic characterization and adsorption/neutralization behavior of waste egg shell for heavy metal ion have been studied for its application to wastewater treatment. To investigate the structural change and thermal decomposition characteristics of egg shell. X-ray diffraction and FT-IR analysis were conducted for egg shell treated at $105^{\circ}C$ and $700^{\circ}C$, respectively. For the result of FT-IR analysis, the sample treated at $700^{\circ}C$ showed a reduced C-O absorption band compared with that of egg shell treated at $105^{\circ}C$, which may be due to the $CO_2$ release. Unlike to the result of FT-IR analysis, the XRD patterns of egg shell were almost similar for the cases of $105^{\circ}C$ and $700^{\circ}C$ treatment. however, characteristic diffraction pattern of CaO was observed for $850^{\circ}C$ treatment, at which $CaCO_3$ is known to be completely converted to CaO. TGA/DTA analysis showed a slow decline in weight loss up to $600^{\circ}C$ and, for $600{\sim}800^{\circ}C$ range, the weight loss became drastic by reason of $CO_2$ discharge, which was accompanied by an appearance of major endothermic peak. The ratio of practical breakthrough time to ideal one, total transfer unit, and mass transfer coefficient were observed to be increased as the adsorption was progressed in a multiple-column fixed-bed reactor using egg shell as an adsorbent, which signified the distribution effect of mass transfer for continuous adsorption reaction. The neutralization effect of egg shell for several types of acidic wastewater made of different mineral acids was not much different from each other except for the case of $H_2SO_4$, for which the neutralization reaction was thought to be retarded by the formation of gypsum.

• Journal of Conservation Science
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• v.32 no.2
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• pp.273-291
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• 2016

Some ceramic artifacts representing time-wise from comb pattern pottery in the Neolithic Age to white porcelain in Joseon Dynasty were selected from 7 sites in the north and south area of Charyeong Mountain Range in order to making techniques interpretation and development process of ancient ceramics through physicochemical and mineralogical quantitative analysis. Studied pottery samples in the Prehistoric times showed trace of ring piling in soft-type, and pottery in the Three Kingdoms Period had both soft and hard-type but kettle-ware and storage-ware were made with ring piling, but table-ware was made by wheel spinning. Different from pottery after the Three Kingdom Period when refinement of source clay was high, pottery in the Neolithic Age and in the Bronze Age exhibited highly mineral content in sandy source clay, which showed a lot of larger temper than source clay. Groundmass of celadon and white porcelain almost did not reveal primary minerals but had high content of minerals by high temperature firing. Ceramic samples showed some different in major and minor elements according to sites irrespective of times. Geochemical behaviors are very similar indicating similar basic characteristics of source clay. However, loss-on-ignition showed 0.01 to 12.59wt.% range with a large deviation but it rapidly decreased moving from the Prehistoric times to the Three Kingdom Period. They have correlation with the weight loss due to firings, according to burning degree of source clay and detection of high temperature minerals, estimated firing temperatures are classified into 5 groups. Pottery in the Neolithic Age and in the Bronze Age belongs from 750 to $850^{\circ}C$ group; pottery in the Three Kingdom Period are variously found in 750 to $1,100^{\circ}C$ range of firing temperature; and it is believed celadon and white porcelain were baked in high temperature of 1,150 to $1,250^{\circ}C$. It seems difference between refinement of source clay and firing temperature based on production times resulted from change in raw material supply and firing method pursuant to development of production skill. However, there was difference in production methods even at the same period and it is thought that they were utilized according to use purpose and needs instead of evolved development simply to one direction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.338-346
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• 2017

Natural seaweed beds and habitat environments were investigated using quantitative and qualitative methods from May to December 2015 at 3 sites in Gangneung, Uljin, and Busan along the eastern coast of Korea. In total, 9 green, 23 brown, and 64 red algal taxa were identified. The biomass of the seaweed at Gangneung was 173.2 to $613.8wet\;wt.g/m^2$ of Dictyota divaricata, 360.8 to $520.4wet\;wt.g/m^2$ of Symphyocladia linearis, and 25.9 to $470.8wet\;wt.g/m^2$ of Undaria pinnatifida. At Uljin, these numbers were 5.5 to $256.2wet\;wt.g/m^2$ of Plocamium telfarirae and 46.8 to $241.5wet\;wt.g/m^2$ of Agarum clathratum. The biomass of Sargassum coreanum and Ecklonia cava were 388.1 to $6,972.4wet\;wt.g/m^2$ and 194.9 to $958.5wet\;wt.g/m^2$, respectively, at Busan. S. coreanum and E. cava showed higher biomass compared to other seaweed at Busan. The biomass rate represented an average of 19.2 percent of the total population, ranging from 0.0 to 55.5 percent in Gangneung. In Uljin, the average was calculated as 63.8 percent, and this figure was 48.5 percent in Busan. The percentage of barren ground averaged 46.7 percent in Gangneung and 91.1 percent in Uljin. Uljin showed the highest percentage of barren ground compared to other regions. Sea urchin density appeared to be $6.0ind./m^2$ in Gangneung, $7.0ind./m^2$ in Uljin, and $2.0ind./m^2$ in Busan, with the lowest sea urchin density being that of Busan. In conclusion, the composition of species, appearance ratio, and abundance of vegetation found were similar to previous studies, but it is thought that continuous monitoring is needed due to concerns about physical and chemical pollution caused by global warming, climate change, and coastal development.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.278-285
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• 2016

The bifunctional PheA protein, having chorismate mutase and prephenate dehydratase (CMPD) activities, is one of the key regulatory enzymes in the aromatic amino acid biosynthesis in Escherichia coli, and is negatively regulated by an end-product, phenyalanine. Therefore, PheA protein has been thought as useful for protein engineering to utilize mass production of essential amino acid phenylalanine. To obtain feedback resistant PheA protein against phenylalanine, we mutated by using random mutagenesis, extensively screened, and obtained $pheA^{FBR}$ gene encoding a feedback resistant PheA protein. The mutant PheA protein contains substitution of Leu to Phe at the position of 118, displaying that higher affinity (about $290{\mu}M$) for prephenate in comparison with that (about $850{\mu}M$) of wild type PheA protein. Kinetic analysis showed that the saturation curve of $PheA^{FBR}$ against phenyalanine is hyperbolic rather than that of $PheA^{WT}$, which is sigmoidal, indicating that the L118F mutant enzyme has no cooperative effects in prephenate binding in the presence of phenylalanine. In vitro enzymatic assay showed that the mutant protein exhibited increased activity by above 3.5 folds compared to the wild type enzyme. Moreover, L118F mutant protein appeared insensitive to feedback inhibition with keeping 40% of enzymatic activity even in the presence of 10 mM phenylalanine at which the activity of wild type $PheA^{WT}$ was not observed. The substitution of Leu to Phe in CMPD may induce significant conformational change for this enzyme to acquire feedback resistance to end-product of the pathway by modulating kinetic properties.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.1
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• pp.47-53
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• 2011

$SF_6$ (Sulfur hexafluoride) possesses high GWP (Global Warming Potential) as sepcified by the IPCC (Intergonvernmental Panel of Climate Change). Recently, the recovery-separtion of $SF_6$ research area, including permeation properties studies using various membrane's materials and the practical operation of recovery-separtion using membrane of waste $SF_6$ gas is in the initial state. The separation efficiency of a single $SF_6$ and waste $SF_6$ mixture was evaluated using a PSF (polysulfone), PC (tetra-bromo polycarbonate) and PI (polyimide) hollow fiber membranes. According to the results of single gases permeation properties, PI membrane has the highest permselectivity of $N_2$ gas in $N_2/SF_6$ gas. Under the condition of P=0.5 MPa, the highest concentration of recovered $SF_6$ is 95.6 vol % in the separation experiment of $SF_6/N_2$ mixture gas by PC membrane. Under the operation pressure of P=0.3 MPa at a fixed retentate flow rate fixed of 150 cc/min, the maximum recovery efficiency of $SF_6$ is up to 97.8% by PSF membrane. From the results above, it is thought that the separation and recovery technique of $SF_6$ gas using membrane will be used as the representative eco-technology in the $SF_6$ gas treatment in the future.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.272-279
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• 2021

A pump-type eDNA filtering system that can control voltage and hydraulic pressure respectively has been developed, and applied a filter case that can filter out without damaging the filter. The filtering performance of the developed system was evaluated by comparing the eDNA concentration with the conventional vacuum-pressured filtering method at the catchment conduit intake reservoir. The developed system was divided into a voltage control (manual pump system) method and a pressure control (automatic pump system) method, and the pressure was measured during filtering and the pressure change of each system was compared. The voltage control method started with 65 [KPa] at the beginning of the filtering, and as the filtering time elapsed, the amount of filtrate accumulated in the filter increased, so the pressure gradually increased. As a result of controlling the pressure control method to maintain a constant pressure according to the designed algorithm, there was a difference in the width of the hydraulic pressure fluctuation during the filtering process according to the feedback time of the hydraulic pressure sensor, and it was confirmed that the pressure was converged to the target pressure. The filtering performance of the developed system was confirmed by measuring the eDNA concentration and comparing the voltage control method and the hydraulic control method with the control group. The voltage control method obtained similar results to the control group, but the hydraulic control method showed lower results than the control group. It is considered that the low eDNA concentration in the hydraulic control method is due to the large pressure deviation during filtering and maintaining a constant pressure during the filtering process. Therefore, rather than maintaining a constant pressure during filtering, it was confirmed that a voltage control method in which the pressure is gradually increased as the filtrate increases with the lapse of filtering time is suitable for collecting eDNA. As a result of comparing the average concentration of eDNA in lentic zone and lotic zone as a control group, it was found to be 96.2 [ng µL^-1] and 88.4 [ng µL^-1l], respectively. The result of comparing the average concentration of eDNA by the pump method was also high in the lentic zone sample as 90.7 [ng µL^-1] and 74.8 [ng µL^-1] in the lentic zone and the lotic zone, respectively. The high eDNA concentration in the lentic zone is thought to be due to the influence of microorganisms including the remaining eDNA.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.4
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• pp.48-59
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• 2014

This study was carried out to present raw data on managing the restored urban stream by studying the naturalized plants distributed in Gaeumjeong Stream, Changwon-si, Gyeongsangnam-do, Korea. The results were as follows. The numbers of naturalized plants were summarized as 45 taxa including 17 families, 36 genera, 43 species and 2 varieties. The invasive alien plants were 2 taxa including Ambrosia artemisiifolia and Lactuca sativa. The following summarizes the attributes of the naturalized plants. Most of the plants commonly originated from Europe and North America. The 5 naturalized degree that was widely distributed and had many individual was the most common. Until 1921, after the opening of 1 period was the most common in the introduced period. Section 12 had the highest NI at 41.9%, and the lowest, at 20.5%, in sections 9 and 19 were analyzed. Section 1 had the highest UI at 6.2%, whereas, the lowest, at 2.5%, was calculated in sections 19 and 20. Section 2 showed the highest DI at 16.7%. The first results of the analysis of the causes for the invasion of naturalized plants on the riverside and waterways, and physical factors and maintenance are directly affected. Second, sewage, muddy water and sediment deposits this naturalized plant caused by a chemical factor. Third, it is thought that invasive alien plants are irregular as it happens in biological factor. The proposed management plan naturalized plants, the first, disturbance caused by species management is a young object is removed immediately before flowering scape to eliminate or suppress the propagation of physical methods will be needed. Second, the fact that the national spread of native plant species and planting management does not provide space for the growth is very important. Third, agricultural land is disturbed by agricultural practices by interfering with the action of naturalized plants because the source of the river should be prohibited in agriculture. In the future, if we studied the naturalized plants distributed in restored streams located in Changwon-si, the characteristics of change in the ecosystem impact is expected to be beneficial.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.389-394
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• 2006

The change of antioxidative character by germination of brown rice was evaluated. From the total methanolic extract of brown rice, 2.5 mm-germinated brown rice, and 5 mm-germinated brown rice, SOD-like activity and nitrite scavenging ability were identified as antioxidative character. SOD-like activities and nitrite scavenging abilities of all samples were changed dose-dependently and germination-dependently. After successive partitioning with hexane, ethyl acetate (EtOAc) and water, each fraction was tested for these activities. SOD-like activities of all fractions were increased by germination, and especially hexane fraction and EtOAc fraction of 5 mm-germinated brown rice had more strong activities than 50 ppm vitamin C. The $EC_{50}$ values of SOD-like activity showed a gradual decrease by germination and that of EtOAc fraction of 5 mm-germinated brown rice was 17 ppm, which was lower concentration than that of 50 ppm vitamin C. The $IC_{50}$ values of nitrite scavenging ability at PH 1.5 also underwent a great decrease by germination and germinated brown rice had the nitrite scavenging ability at lower concentration than brown rice. The results suggest that SOD-like activity and nitrite scavenging ability are thought to be enhanced by the germination effect.

• Archives of design research
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• v.18 no.3 s.61
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• pp.117-128
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• 2005

The French Belle Epoque is a period where the literary and artistic movement was very activated. The birth of the cubism reflects this atmosphere of the times and the change of paradigm in all fields. The Bergsonism is often designated as one of the important backgrounds of cubism. The problem consists in knowing if Bergsonian ideas gave real influence on the cubist movement and up to what point. Our analysis will show that it is not homogenous and very variable according to painters. In the case of Picasso and Braques it seems be a simple inspiration of Zeitgeist. But the influence upon Metzinger and Gleizes is explicit. The text of 1912, Du cubism, prove their attachment to his thought. The key concept of cubist theory, influenced by Bergsonian philosophy, is the concept of simultaneity. Cubist simultaneity is in one hand a reflection of an artist's psychological experience and the other hand a synthesis of multiple views for grasping the object in itself by the way of conceptual representation. The temporal simultaneity could be identified with the notion of memory, which is a temporal continuity connecting the past to dynamic present. The spatial simultaneity is a juxtaposition of multiple views obtained by the movement around the object. But the dose reading of Bergson's text shows that there is a divergence between the notion of cubist simultaneity and his ideas. The biased interpretation is often, as well as the strict understanding, like the history shows us well, a great source of inspiration and creativity. The cubist mouvement is not far from this case.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.421-431
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• 2021

It has been suggested that some toothpastes have the potential to promote hair growth. However, there was no scientific verification on the hair growth effect of toothpaste and no scientific report on major active ingredients in toothpaste. In this work, toothpaste and its constituents were applied topically over the shaved skin of C57BL/6 mice and evaluated. Results indicated that toothpaste showed hair growth effect. Also, the effect of toothpaste constituents on the proliferation rate of keratinocyte cells was investigated. The mixture solution of 𝛼-tocopherol acetate, l-menthol, and stevioside, each of that was known to promote hair growth and other toothpaste constituents were applied topically on mouse skin. When the mixture solution was included, hair growth effect was observed in mice. Transcriptome analysis was performed using the dorsal epidermis of mice from the group treated with toothpaste, the mixture which are presumed to be active ingredients for hair growth, and from mice used for the control group. As a result of analyzing the genes whose expression was significantly changed in each treatment group, the gene patterns of the two groups were very similar. Also, when functional genomic analysis was performed, genes with functions related to hair growth regulation showed a high extent of the change in both groups. Hair growth-related genes whose expression was changed in both groups included keratin, keratin-related proteins, forkhead box, and sonic hedgehog. Therefore, the hair growth effect of toothpaste is thought to be due to the effect of a mixture of 𝛼-tocopherol acetate, l-menthol, and stevioside.