• Journal of Environmental Science International
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• 제5권6호
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• pp.813-826
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• 1996

The toxic effects of aluminium (Al) on growth, chlorophyll content, $\delta-aminolevulinic$ acid dehydratase (ALAD) activity and anatomy of root and shoot were investigated in 7-day-old azuki bean (Vigna angularis) seedlings. Significant depressions in root elongation was observed in the low concentrations of Al (50, 100 $\muM)$ and increasing Al concentrations caused a sharp decline of root and shoot growth. The degree of inhibition was dependent upon Al supply. Exposure to 50 $\muM$ Al or more inhibited root elongation within 1 day. In the 50 $\muM$ Al treatments, a recovery of root growth was seen after 7 days exposure. In contrast, lateral root initials was little affected by Al exposure. Al toxicity symptoms and growth responses were more well developed in the roots than in the shoots. Analysis of Al localization in root cells by hematoxylin stAlning showed that Al entered root apices and accumulated in the epidermal and cortical cells immeadiately below the epidermis. There was a good positive correlation between the level of chlorophyll and ALAD activity. Increasing Al concentrations caused a decrease in total chlorophyll contents, accompanied by proportional changes in ALAD activity, suggesting a cootr-dinated reduction of a photosynthetic machinery. Al exerted specific influence on the morphology of root ann shoot. At higher concentrations of Al the roots induced drastic anatomical changes. The epidermal cells were disorganized or destructed while the cortical cells exhibited distortion of cell shape and/or disintegration. The diameter of root and transectional area of cortical cells decreased considerably with Al treatment. In the shoot Al also enhanced reduction of diameter of shoot and cell size. Gross anatomy of leaves treated with Al did not differ significantly from the controls, except for fewer and smaller chloroplast. Our results indicate that toxic effect of Al appear to be manifested primarily in roots and secondarily on shoots, and changes in root morphology are related to changes in the root growth patterns. Results are further discussed in re181ion to the findings in other plant species, and it is concluded that Al causes morphological, structural and, presumably, functional damage to the roots of the species investigated.

• Journal of the Korean Ceramic Society
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• 제50권4호
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• pp.288-293
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• 2013

Zn-In-Sn-O films were prepared at room temperature by combinatorial RF-magnetron co-sputtering system. The cationic contents of the films were varied using a compositionally combinatorial technique. The effects of the oxygen partial pressure and film compositionon the structural and electrical properties were investigated. The Zn-In-Sn-O films deposited at Ar gas atmosphere showed an amorphous phaseirrespective of the film composition. However, the amorphous Zn-In-Sn-O films with a Zn content below 30.0 at% were converted into a bixbyite type-ITO polycrystalline phase with an increase in the oxygen partial pressure. The resistivity, carrier concentration, and Hall mobility were strongly affected by the oxygen partial pressure and chemical composition of the film. At sufficiently high carrier densities above $5{\times}10^{18}cm^{-3}$, the conduction behavior of amorphous Zn-In-Sn-O film changes from thermally activated to degenerate band conduction accompanied with high mobility.

• Food Science and Biotechnology
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• 제15권3호
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• pp.418-423
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• 2006

Egg white powders (EWPs) were produced after pH adjustment (PH 6-9) of fresh egg white, followed by spray-drying, and foaming and gelling properties of EWPs were examined. EWP produced after pH adjustment to 6.5 (EWP-6.5) resulted in significantly higher foaming ability and gel hardness than control and other pH-adjusted EWP. Significant increases in surface -SH content and surface hydrophobicity of EWP-6.5 coincided with improved foaming ability and gel hardness. Significantly higher consistency index for reconstituted EWP-6.5 indicates unfolding of egg white protein was substantially increased in EWP-6.5. Decreased a-helix content in EWP-6.5 was confirmed by circular dichroism spectral analysis. These results indicate pH adjustment prior to spray-drying leads to structural changes in egg white proteins, significantly affecting major functionalities of EWP.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• 제26권4호
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• pp.289-293
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• 2013

We have studied structural, optical, and electrical properties of the Ga-doped ZnO (GZO) thin films being usable in transparent conducting oxides. The GZO thin films were deposited on the corning 1737 glass plate by the RF magnetron sputtering system. To find optimal properties of GZO for transparent conducting oxides, the Ar gas in sputtering process was varied as 40, 60, 80 and 100 sccm, respectively. As reaction gas decreased, the crystallinity of GZO thin film was increased, the optical bandgap of GZO thin film increased. The transmittance of the film was over 80% in the visible light range regardless of the changes in reaction gas. The measurement of Hall effect characterizes the whole thin film as n-type, and the electrical property was improved with decreasing reaction gas. The structural, optical, and electrical properties of the GZO thin films were affected by Ga dopant content in GZO thin film.

• Journal of the Korean Ceramic Society
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• 제26권4호
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• pp.559-567
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• 1989

Bioglasses have been known to be as one of the promising biomateials, which can be used for replacing defective hard and soft tissue. There have been many reports on biological results for this type of glass, but no systematic work has carried out on the structures and properties of the bioglass itself. In the present study, the effect of P2O5 in bioglasses on their structures and properties was examined. Infrared and Raman spectroscopy for the glass structural analysis, differential thermal and X-ray diffraction analysis for the crystallization of the bioglass were performed, and several physical properties were measured. When the glasses were heat-treated, Na2O.2CaO.3SiO2 was the major crystalline phase and $\beta$-NaCaPO4 crystal was found for the glass with high P2O5 content. The added P2O5 in the glasses enhanced the polymerization of silicate glass structure and it changed the chain-like glass structure to a sheet-like structure, and some P2O5 may stay as phosphate monomer. With addition of P2O5 in the glass the density of the glasses decreased, but not much changes in their thermal expansion coefficient, softening point and microhardness were observed.

• Culinary science and hospitality research
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• 제9권2호
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• pp.85-97
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• 2003

This study is an attempt that Rheology changes are occurred by boiling, frying, and boiling potatoes with soy bean sauce. Three different methods are tested for chemical analysis, fine potato starch grain structural change, sensory evaluation. 1) Alkaline number and acidity number are changed (+)2.17 in raw, decreased (+)1.76 by boiling, increased (+)2.38 by frying, and (-)2.22 by boiling with soy bean sauce. 2) Potatoes are completely dissolved into the gelatinization when they are boiled at 10$0^{\circ}C$ for 15minutes(PB III), fried at 18$0^{\circ}C$ for 3 minutes(PF IV), and boiled with soy bean sauce l0$0^{\circ}C$ for 30 minutes(PS III). 3) The pectin content ratio is decreased according to frying (31.78$\mu\textrm{g}$/$m\ell$), boiling(44.20$\mu\textrm{g}$/$m\ell$), boiling soy bean sauce(36.37 $\mu\textrm{g}$/$m\ell$), Hemicellulose content ratio is decreased according to frying(1.19%), boiling(1.17%), boiling soy bean sauce(0.92%). And the contend of cellulose and lignin is still regardless of any cooking method. 4) The sensory evaluation conducted by 30 university students as panelists showed that there are more significant differences among four samples in appearance, flavour, texture. As a result, the optimum cooking condition for potatoes is that potatoes are boiled l0$0^{\circ}C$ for 15minutes, fried at 18$0^{\circ}C$ for 3minutes, and boiled with soy bean sauce at 1$0^{\circ}C$ for 30minutes.

• Journal of the Korea Furniture Society
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• 제27권2호
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• pp.122-127
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• 2016

The increasing interest in the environment and climate change around the globe, while the importance of building energy saving is increasing. The building energy simulation program is used for evaluating of energy performance of buildings. However, an input value of wood thermal conductivity in the programs is different from each other. Therefore, in this study, wood thermal conductivity was measured according to species. Through construction database by species of wood, the error of simulation program are able be decreased. In addition, if used as a structural and interior of buildings, the thermal conductivity and moisture of the wood is difficult to apply to the program because they were changed according to the occupant's lifestyle. In this paper, thermal conductivity and moisture content.of wood confirmed changes in the constant temperature and relative humidity ($25^{\circ}C$, 50% R.H.) condition.

• Journal of the Korean Wood Science and Technology
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• 제49권1호
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• pp.14-22
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• 2021

The objective of this study was to investigate the effect of alkali-washing with different sodium hydroxide concentrations on the chemical compositions of steam-treated Betung bamboo strand. Strands were subjected to steam treatment at 126 ℃ for 1 h under 0.14 MPa pressure and followed by washing with 1-5% sodium hydroxide solution for 30 sec. The alteration of structural and non-structural chemical components content of bamboo strands was evaluated. Steam and washing treatments with various concentrations of sodium hydroxide solution considerably reduced the extractive content of bamboo strands, and the cell wall chemical components of the strand in the small degree. FTIR analysis showed noticeable changes in peaks related to hemicellulose and lignin. The relative crystallinity increased significantly after steam and washing treatment with sodium hydroxide up to 3% concentration. SEM Images showed smooth and clean strands surface after washing with 3% sodium hydroxide.

• Korean Journal of Food Science and Technology
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• 제53권5호
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• pp.514-520
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• 2021

This study identified and quantified the sugar-related metabolites and analyzed the structural features of starch in kimchi added with various concentrations of glutinous rice paste during fermentation. The pH values and total bacterial counts indicated that the fermentation of kimchi with 10% glutinous rice paste progressed more quickly than that of kimchi with other rice paste concentrations. The addition of glutinous rice pastes to kimchi resulted in increased glucose and decreased fructose contents during fermentation compared to the control kimchi. Maltose content increased significantly with increasing glutinous rice paste concentrations. The average chain length distribution of starch in kimchi decreased with increasing proportions of short chains as fermentation progressed. However, the average chain length distribution of starch increased with increasing glutinous rice paste concentration in kimchi. Our results confirmed that the sugar-related metabolites and starch structural changes were highly influenced by the added starch paste concentration.

• The Journal of the Korea Contents Association
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• 제17권9호
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• pp.341-352
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• 2017

Regarding "Supply-side Structural Reforms of Chinese Cultural Industry(供給側結枸性改革)" that has been genuinely promoted since 2016 in China, this study aims to analyze research trends in academic circles and policies carried out by the government and draw implications about what culture industry should pursue in Korea. First of all, research conducted through industrial-educational cooperation mainly and commonly points out such problems as imbalance between demand and supply, oversupply, low culture consumption, absurdity in loans and investments structures, and lack of international influence and demands reformation. In the side of the government, <13.5 Plan for Developing Culture Industry promoted from 2016 to 2020 reflects the government's strong will taking structural reformation in the side of supply as its major route and presenting tasks to reform culture industry in general. Next, concerning implications for Korea, this author suggests them in five areas: to establish directions for new culture industry policies reflecting the changes of environment in culture industry, say, the advent of the 4th industrial revolution, to increase valid supply correspondingly to consumer demand, to improve loans and investments systems, to enlarge demand markets, and to form environment for fair market competition.