• Polymer(Korea)
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• v.38 no.3
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• pp.397-405
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• 2014

To manufacture of high-performance semi-structural double-sided adhesive tape, 2-ethylhexyl acrylate (2-EHA) and acrylic acid (AAC) were used, and the syrup was prepared by UV irradiation in this study. The effects of the thickness, various inorganic filler contents, and filler types on the semi-structural properties of acrylic double-sided adhesive tape were investigated. The peel strength increased with increasing thickness and wetting time. In case of the thin thickness (under $250{\mu}m$) with decreasing true density of inorganic filler, the peel strength increased with increasing wetting time. The initial peel strength showed a higher value at a big size of inorganic filler, and the filler's size in adhesive tapes was confirmed by SEM images. The peel strength and dynamic shear strength increased as a proportional relationship with various inorganic fillers and contents, and these inorganic fillers in $0.1{\mu}m$ thickness indicated more effect on the dynamic shear strength of double-sided adhesive tape. From these results the thin acrylic double-sided adhesive tape determined to be use for applications as a high-performance semi-structural.

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.273-284
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• 2020

Calocybe indica is an edible mushroom commercially cultivated in India and other tropical countries. In this study, the culture characteristics and optimal conditions of milky mushroom strains were determined. The growth temperature and pH range of milky mushrooms was extensively investigated between 15-35 ℃ and pH 3-11. For efficient cultivation, 20 types of nutrient sources were selected that consisted of one of 21 types of carbon sources, 6 organic nitrogen sources, 6 inorganic nitrogen sources, 13 amino acids, 6 organic acids and 12 inorganic salts. The impact of each of the selected nutrition sources and their concentration on growth was investigated. The optimum pH and temperature were determined to be pH 6.0 and 15 ℃, respectively. The optimum concentration of medium elements for the mycelial growth of C. indica was determined to be as follows: carbon source, 2% maltose; organic nitrogen source, 1% yeast extract; inorganic nitrogen source, 0.1% NaNO₃; amino acid, 0.7% asparagine; organic acid, 0.07% acetic acid; inorganic salt, 0.07 mM MnSO₄.

• Journal of Life Science
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• v.13 no.1
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• pp.110-117
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• 2003

A thermotolerant yeast strain, Saccharomyces cerevisiae KNU5377 (abbreviated as KNU5377, was exposed to inorganic acids including sulfuric, nitric and hydrochloric acid. As a stressor, each inorganic acid is very easily dissociated in water, resulting in lowering environmental pH. When compared with a reference S. cerevisiae ATCC24858, KNU5377 could overcome such a severe condition containing a final 0.4% concentration of sulfuric acid or nitric acid to grow at the overnight culture, but this reference could not. Additionally, this strain showed a surprisingly strong tolerance by surviving despite of exposure to the regime of 0.35% of hydrochloric acid for over 90 min and also to 0.6% of sulfuric acid for 30 min. On the contrary, both strains could not survive against a final 0.45% concentration of nitric acid. This strain KNU5377 could produce ethanol of 3% in 2 days by using the fermentation medium containing a final 0.3% concentration of sulfuric arid. Moreover, change into a final 0.2% concentration of sulfuric acid caused this strain to enhance fermentation productivity up to about 4.5% even at $40^{\circ}C$. In exposure to a final 0.2% of sulfuric acid for 60 min, trehalose was most accumulated within 30 min in KNU5377, and this suggested a cellular defense system led by this disaccharide was profitable for this strain to lead to no morphological changes.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.101-101
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• 1989

Multilayer films of inorganic analogues of Langmuir-Blodgett films have been prepared on silicon and gold substrates and characterized by ellipsometry, XPS, FT-IRRS, and electrochemical measurements. The deposition technique requires first covalent attachment or adsorption of a phosphonic acid anchoring agent; $HO(CH_3)(CH_2)_2Si(CH_2)_3PO_3H_2$ and $[-S(CH_2)_4PO_3H_2]_2$ were used with Si and Au, respectively. The functionalized substrates are exposed alternately to aqueous $ZrOCl_2$ and l,l0-decanediylbis(phosphonic acid) solutions to yield multilayer films. Surface-sensitive probes show that the films are compact and grow in an oriented fashion suggestive of good structural order.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.90-96
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• 1994

Changes in haemolymph proteins, hydrolases such as esterase(EST), acid phosphatase(ACP) and alkaline phosphatase(ALP) , and inorganic ion(Na+, K+ and Cl- ) contents were induced by the injection of Bacillus thuringiengis into haemocoel of the last instar larva of Heliothis assulta. Protein concentration of haemolymph was increased until 24 hrs after injection, and decreased thereafter. Among the 8 basic protein bands identified through acid - polyacrylamide gel electrophoresis(PAGE), 2 bands(bands a and b) became stronger by the bacterial infection. Activities of EST and ALP increased until 12 hrs after injection and then fell down, whereas ACP activity was decreased continuously with time after injection. Contents of inorganic ions were all increased by the bacterial injection, showing slow rate of increase in the chloride ion, but rapid in the sodium and potassium ions.

• Mass Spectrometry Letters
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• v.11 no.4
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• pp.108-112
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• 2020

A certified reference material (CRM) for the analysis of nutrient elements in an edible mushroom (Ganoderma lyceum) powder has been developed (KRISS CRM 108-10-011). The mass fractions of calcium (Ca), iron (Fe), and zinc (Zn) were measured by isotope dilution inductively coupled plasma mass spectrometry (ID ICP/MS). To dissolve the fungi cell wall of mushroom consisted of chitin fibers, sample preparation method by single reaction chamber type microwave-assisted acid digestion with acid mixtures was optimized. The mean measurement results obtained from 12 sample bottles were used to assign as the certified values for the CRM and the between-bottle homogeneities were evaluated from the relative standard deviations. The certified values were metrologically traceable to the definition of the kilogram in the International System of Units (SI). This CRM is expected to be used for validation of analytical methods or quality control of measurement results in analytical laboratories when they determine the mass fractions of elements in mushroom or other similar samples.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.13-14
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• 1957

Th-determination by the sebacic acid method was compared with the hydrogen peroxide method. The former is a little more complicated than the latter in the operation and at the same time it requires careful pH adjustment, but the time needed for determination could be decreased greatly by the former. As a result of the comparison between both methods we confirmed that, within ${\pm}$0.08 ${\%}$ of error, when $ThO_2$ was contained $5{\%}$ in the sample, we could use the sebacic acid method with an half time of that required for the hydrogen peroxide method. Thorium in Monazite sand was also determined by both methods and compared. In the case we found, too, that if we permitted the maximum error of ${\pm}$0.08 ${\%}$, we could prefer the sebacic acid method.

• Journal of Plant Biology
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• v.19 no.3
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• pp.71-84
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• 1976

In order to observe the phosphate metabolism in chloroplast, the contents of inorganic phosphate and various compounds in chloroplast from spinach leaf tissues were investigated during the reaction in the light and dark in the reaction mixture and the turnover of phosphate in chloroplast was compared with that of whole cell system: 1. The phosphorus of DNA in chloroplast appears to be transferred from inorganic phosphate, while in whole cell system from phosphate pool. 2. $^{32}P-phosphate$ content of acid soluble fraction in chloroplast as well as in whole cell system was more increased in the light than dark during the reaction. It was noted to be caused by the stimulation of sugar phosphate synthesis in the light. 3. It was confirmed that polyphosphate exists in chloroplast as well as whole cell. Acid insoluble polyphosphate content in whole cell system was significantly decreased during the reaction and the similar tendency was also observed in chloroplst. It is, therefore, considered that acid insoluble polyphosphate also play an most important role as a phosphate pool respectively in chloroplast and in cytoplasm. 4. Protein and lipid phosphorus in chloroplast as well as whole cell system were transferred from acid insoluble polyphosphate.

• Asian Journal of Atmospheric Environment
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• v.4 no.1
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• pp.55-61
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• 2010

The sensitivity of aerosol light extinction coefficient to the aerosol chemical composition change is estimated by (1) calculating the aerosol water content and chemical concentrations by a gas/particle equilibrium model and (2) calculating the aerosol light extinction coefficient by a Mie theory based optical model. The major chemical species are total (gas and particle phase) sulfuric acid, total nitric acid, and total ammonia which are based on the measurement data at Seoul and Gosan. At Seoul, since there were enough ammonia to neutralize both total sulfuric acid and total nitric acid, the dry ionic concentration is most sensitive to the variation of the total nitric acid level, while the total mass concentration (ionic concentration plus water content) and thus, the aerosol light extinction coefficient are primarily determined by the total sulfuric acid. At Gosan, since the concentration of ambient sulfuric acid was the highest among the inorganic species, sulfate salts determined aerosol hygroscopicity. Thus, both ionic and total mass concentration, and resultant aerosol light extinction coefficient are primarily determined by the sulfuric acid level.

• Journal of the Korean Wood Science and Technology
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• v.34 no.4
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• pp.15-21
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• 2006

Composite materials were prepared by impregnating water glass into the wood, followed by soaking in solutions of boric acid or phosphoric acid. The effects of these treatments on the physical and mechanical properties of the specimens and especially on its heat resistance were investigated. 1) Weight Percent Gain (WPG)s increased with increase of concentrations of water glass. However, there was little relationship between treatment temperatures and WPG. Generally, WPGs of double treated specimens were higher than single treated ones. 2) Percent shrinkages in each directions of the specimens treated with water glass had higher value than other specimens. Percent shrinkages of the specimens treated with boric acid or phosphoric acid were decreased as compared with untreated specimen. However, the specimens treated with water glass or phosphoric acid showed very high hygroscopicity. 3) The bending strengths of all specimens treated inorganic substances were slightly decreased. However, the values of compressive strength and hardness of most specimens treated with inorganic substances increased or similar to that of untreated specimen except for a phosphoric acid treated specimens. 4) The specimens had good heat resistance. Weight losses of all specimens treated inorganic substances were about 50~70%. In particular, the specimens treated at $300^{\circ}C$ and $400^{\circ}C$ almost kept their shapes.