• Journal of the Korean Wood Science and Technology
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• v.9 no.3
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• pp.16-23
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• 1981

This study has been carried out to make a comparative study for the adhesive control methods specifically developed for application to formaldehyde. The method for formaldehyde determination used in this report is the improved chromo tropic acid determination. The results are summarized as follows: 1. The soaking treatment in aqueous solution of urea wok the most scavenging effect on the formaldehyde release from a plywood sample glued with a urea formaldehyde adhesive, and other removal treatment such as resorcinol, albumine-, and hardener-treatment gave significant reduction too. 2. In glue shear strength of dry test, 2% of resorcinol treatment and soaking treatment showed the highest strength and all the other treatment met the standard, but in hot water soaking test, 2% of resorcinol treatment gave the best results, on the other hand, adding the hardener showed the lowest strength and failed in meeting the standard. 3. Air dried moisture content of all treated plywood met the standard which calls for 13% or bellow. 4. In this comparative study, we can make a strong combination each other or go into the details of one treatment for the best result through the more study.

• Korean Journal of Materials Research
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• v.22 no.7
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• pp.379-383
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• 2012

$TiO_2$ thin films consisting of positively charged poly(diallyldimethylammonium chloride)(PDDA) and negatively charged titanium(IV) bis(ammonium lactato) dihydroxide(TALH) were successfully fabricated on glass beads by a layer-by-layer(LBL) self-assembly method. The glass beads used here showed a positive charge in an acid range and negative charge in an alkaline range. The glass beads coated with the coating sequence of(PDDA/TALH)n showed a change in the surface morphology as a function of the number of bilayers. When the number of bilayers(n) of the(PDDA/TALH) thin film was 20, Ti element was observed on the surface of the coated glass beads. The thin films coated onto the glass beads had a main peak of the (101) crystal face and were highly crystallized with XRD diffraction peaks of anatase-type $TiO_2$ according to an XRD analysis. In addition, the $TiO_2$ thin films showed photocatalytic properties such that they could decompose a methyl orange solution under illumination with UV light. As the number of bilayers of the(PDDA/TALH) thin film increased, the photocatalytic property of the $TiO_2$-coated glass beads increased with the increase in the thin film thickness. The surface morphologies and optical properties of glass beads coated with $TiO_2$ thin films with different coating numbers were measured by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD) and by UV-Vis spectrophotometry(UV-vis).

• Biomolecules & Therapeutics
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• v.2 no.4
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• pp.369-375
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• 1994

A polysaccharide, G009, isolated from Ganoderma lucidum IY 009, was subjected to investigating on general pharmacology. This material at the large oral doses of 1000 and 2000 mg/kg in mice did not exhibit any abnormal behaviors and another effects on central nervous system. It also had no influences on hexobarbital-induced sleeping time, rotarod test and spontaneous activity test at each oral dose of 1000 mg/kg in mice. No effects on the body temperature and on acetic acid induced writhing syndrome in mice were observed with its oral administration at 1000 mg/kg, and the convulsions induced by strychnine and pentetrazole were not inhibited at its oral doses of 1000 mg/kg in mice. The solution of G009 as given intravenously at the doses of 30 and 60 mg/kg in rabbit had no influences on blood pressure and respiration rates and depth. In isolated organs of rat uterus and fundus muscles and guineapig ileum and trachea, it did not show any contraction or relaxation at the concentrations of 2$\times$10$^{-3}$ g/ml, and the contractive actions produced by oxytocin, acetylcholine, serotonin and histamine were not inhibited at the same doses. This material showed no effect on intestinal propulsion test in mice and gastric secretion in rats at the oral doses of 1000 mg/kg. However, it is interesting that the material exhibited potent inhibition of acidified aspirin induced gastric damage at the doses of 500 and 1000 mg/kg in rats.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.267-271
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• 1991

The chemical and organoleptic properties of dongchimi studied for their changes during fermentation at $4{\sim}35^{\circ}C$ in 7% NaCl solution with seasonings. It was found that pH decrease showed three variation points in its slope at about pH 5.2, 4.7 and 4.1 during fermentation. A negative linear relationship between total acidity and logarithmic value of pH was obtained. The slope of the relationship curve was increased as the fermentation temperature increased. The reducing sugar was increased until pH reached$4.0{\sim}4.2$ followed by a small decrease and its amount was lowered as the temperature increased from $4\;to\;25^{\circ}C$ The major nonvolatile organic acids were lactic and citric acids. The increase in lactic acid were more marked at $25^{\circ}C$ than at $4^{\circ}C$. As fermentation proceeded the fresh radish odor significantly decreased while sourness and yeast-moldy odor increased. The crispness of the radish decreased slightly during fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.858-864
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• 2001

This study was performed to investigate the effect of sodium lactate (SL, 60%) and a mixed fat replacer (FR) on the product quality and shelf-life effect of low-fat bologna sausage (LFBS) in a model system during refrigerated storage. Low-fat and regular-fat bologna sausages had pH values ranged from 6.15 to 6.30 and water activity values ranged from 0.95 to 0.96. LFBS had a moisture content of 74~76%, <2% fat and 14~15% protein, whereas regular-fat bologna had 60% moisture, 22% fat and approximately 12% protein in the final products. Expressible moisture (%) increased (p<0.05) in all bolognas, resulting in the soft texture, as the storage time (weeks) increased. LFBS manufactured with SL and a FR had lower (p<0.05) the cooking loss (%) and had higher (p<0.05) texture profile analysis (TPA) values than the regular-fat counterpart. As the sodium lactate level increased up to 5% in the formulation of LFBS, vacuum purge and TPA hardness values also increased (p<0.05), but thiobarbituric acid (TBA) values decreased (p<0.05). Total plate counts of LFBS were reduced (p<0.05) when the addition level of 60% SL solution was more than 3.3%. This result indicated that the increased level of SL (>3.3%) in the combination of a FR in the formulation of LFBS improved the product quality and did inhibit the total microbial growth of LFBS during storage, as compared to the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.139-147
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• 1991

The preservative effect of cellophane film packing on the quality of semi-salted and dried mackerel was studied. The product(P) of semi-salted and dried mackerel was prepared from raw mackerel by filleting, cleaning, soaking in 15%9v/w) salt solution for 30min, draining, packing with cellophane film (PT# 300, thickness:$20{\mu}{\textrm}{m}$) and drying for 4 hrs at $40^{\circ}C$ in hot air dryer. The product (C) was also prepared without cellophane film packing after draining. The product (C) and (P) were stored at $5.0{\pm}0.5^{\circ}C$. After processing and during storage, moisture content of product (P) was higher than that of product (C), but contents of VBN(volatile basic nitrogen), amino nitrogen and TMA of product (P) on dry basis were lower than those of product (C). Viable cell count, TBA value, peroxide value and decreasing rate of polyenoic acid of product (P) were also lower than those of product (C). In sensory evaluation, the shelf life of product (C) was about 9 days and that of product (P) was about 14 days. From the results of chemical and sensory evaluation, it was concluded that cellophane film packing was a good condition for preserving the quality of semi-salted and dried mackerel.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.1
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• pp.1-9
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• 2020

In this experiment, the Grateloupia elliptica (G. elliptica) was fermented using the fungus Aureobasidium pullulans (A. pullulans) and its extract was obtained from hot water and 70% ethanol solution. The extract was studied for their biological activities such as antioxidant effect, Collagenase and tyrosinase inhibition in comparison to the nonfermented exatract in same solvents. Antioxidative activity test using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) showed that ethanol extract had higher antioxidant activity than water extract. Among all of the samples, the antioxidant activity of G. elliptica fermented ethanol extracts (GEFEE) was highest. Tyrosinase inhibitory activity of GEFEE was highest with 9.8% at the 1,000 ㎍/mL concentration. No inhibition of collagenase from G. elliptica water extract (GEWE) and G. elliptica fermented water extract (GEFWE) was observed, but G. elliptica ethanol extracts (GEEE) and GEFEE showed increased collagenase inhibition activity with increasing concentrations of them. Collagenase inhibitory activity of GEFEE was highest with 50.3% at the 1,000 ㎍/mL concentration. MTS cell proliferation assay was conducted with the GEWE, GEEE, GEFWE, GEFEE and cell viability was over 90% at the 10 ㎍/mL ~ 1000 ㎍/mL concentrations for all of the samples, which suggested that the extracts were noncytotoxic. In conclusion, fermented extracts of G. elliptica could be developed to bioactive functional material for cosmetics with antioxidant and wrinkle improvement effects.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.413-418
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• 1985

Tobacco plant(8-leaf seedlings) were grown on water culture fertilized with different N sources ($NO_3-N$, $NH_4-N$, $NO_3+NH_4-N$) during 15 days. Daily uptake of nutrients and inorganic constituents in plants were investigated in relation to growth responses of them. 1. Nitrate-fed plant showed higher daily uptake of inorganic cations than those in other treatments, and reached about two times higher uptake of nitrogen and three times more uptake of cations (K, Ca, Mg). Potassium was preferentially uptaken at a very fast rate from the beginning after treatment. Also $NO_3-N$ tended to be taken up selectively by the plant from the mixture of nitrate and $NH_4-N$. 2. The initial pH (pH 6.0) of culture medium drastically changed into acid (pH 4.0) in the $NH_4-N$ medium, but into slightly higher (pH 6.4) in the nitrate when measured after exposure of 24 hours. The mixture also tended to show an acidity but much weaker than $NH_4-N$ solution. 3. Nitrate-fed plant had a normal growth pattern but $NH_4-N$ fed plant almost stopped growing. Those plants containing both nitrate and ammonium N were also showed very poor growth.

• Applied Chemistry for Engineering
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• v.30 no.4
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• pp.429-434
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• 2019

A lateral flow immunoassay platform utilizing antibody functionalized water soluble CdSe/ZnS semiconductor quantum dots (QDs) was developed for the analysis of human serum amyloid A-1 (hSAA1) in a buffer solution. hSAA1 was chosen as a target protein because it is regarded as a potential biomarker associated with early diagnosis and prognosis in patients of lung cancer. The immunoassay strip on a nitrocellulose membrane was fabricated by spraying two lines composed of a test line with a monoclonal antibody against hSAA1 (10G1) (anti hSAA1) and a control line of anti-chicken IgY. While the CdSe/ZnS QDs synthesized in an organic phase were transferred to a water phase by ligand exchange using carboxylic acid modified alkane thiol. The QDs was then conjugated to monoclonal antibody against hSAA1 (14F8) [anti hSAA1 (14F8)] and used as a fluorescent detection probe. The sequential lateral flow of hSAA1 in different concentration and QDs-anti hSAA1 (14F8) complex allowed to form the surface sandwich complex of anti hSAA1 (10G1)/hSAA1/QD-anti hSAA1 (14F8), which was then analyzed using fluorescence microscope. A 100 nM concentration of hSAA1 protein can be detected by naked eyes under an optimized lateral flow buffer condition with a sensing time of 5 mins.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.601-609
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• 2018

Microcystis aeruginosa, a freshwater cyanobacteria species known to be one of the most predominant species responsible for cyanobacterial harmful algal blooms (CyanoHABs). It has been frequently associated with the contamination of neurotoxins and peptide hepatotoxins, such as microcystin and lipopolysaccharides-LPSs. CyanoHABs control technologies so far put in place do not provide a fundamental solution and cause secondary pollution linked with the control measures. For this study, algicidal peptides, which have been reported to be non-toxic and to have antimicrobial properties, were employed for the development of novel eco-friendly control against CyanoHABs. The four peptides (CMA1, CMA2, HPA3P, and HPA3NT3) selected in this study showed significant algicidal effects against M. aeruginosa cells inducing cell aggregation and flotation. Moreover, the newly generated peptides (K160242-5) with certain modifications also displayed high algicidal activity. The algicidal activity of the peptides was found to depend on the concentrations and structures of each of amino acid. The results of this study suggested a novel possibility of CyanoHABs control using the non-toxic algicidal peptides.