• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.1_2
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• pp.37-43
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• 1973

In this paper, non-enzymatic browning reactions as a factor of self stability of boiled and dried anchovy were studied to discuss the effect of water activity to the discoloring reaction and the preservative moisture content. The development of rancidity of the fish meat was also mentioned since the fish is fatty and the lipid oxidation is a functional deteriorative reaction. Fresh anchovies were boiled in $10\%$ salt solution immediately after the catch, sun dried, and stored at room temperature ($20^{\circ}C$) for two months in humidistat chambers maintaining different levels of water activity as described in Table 1. The pigments formed by non-enzymatic browning reations were extracted in two fractions, those were chloroform-methanol soluble and water dialyzed fraction, and analyzed spectrophotometrically at the wavelength of 460 nm. These two fractions were considered, respectively to be the brown pigments formed by lipid oxidation reactions for the formler and for the latter, to be the pigments developed by sugar-amino or Maillard reaction. The oxidation of lipid in anchovy meat during the storage was measured as the changes in Peroxide value and the color development of thiobarbituric acid reaction. It is summarized from the results that the rate of both reactions, lipid oxidation and browning, was affected by water activity levels. In regard to the changes in peroxide and TBA value during the storage, the propagation of lipid oxidation was obviously accelerated at lower humidities whereas the development of browning progressed at the higher. These two reactions occurring simultaneously and contrary in activity resulted in that the rate of deterioration occurring oxidatively or by browning, was the minimum at the water activity of 0.32-0.45 which were $7-9\%$ as moisture content and slightly higher value than that of monolayer (Aw=0.21, $5.11\%$ as moisture content). It is also noted that the lipid oxidative browning was presumed to dominate sugar-amino reactions so that the rate of browning of the meat was ultimately depended on the development of rancidity although sugar-amino reactions initiated earlier than the other at the first ten days of storage, particulary at higher humidity. At the lower humidity sugar-amino reactions were occurred gradually but lower levels in color development in contrast to the consistent increase in lipid oxidative browning.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.60-65
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• 2005

The electrosorption of U(VI) from waste water was carried out by using activated carbon fiber(ACF) felt electrode in a continuous electrosorption cell. In order to enhance the electrosorption capacity at lower potential, ACF felt was chemically modified in acidic, basic and neutral solution. Pore structure and functional groups of chemically modified ACF were examined, and the effect of treatment conditions was studied for the adsorption of U(VI). Specific surface area of all ACFs decreases by this treatment. The amount of acidic functional groups decreases with basic and neutral salt treatment, while the amount increases a lot with acidic treatment. The electrosorption capacity of U(VI) decreases on using the acid treated electrode due to the shielding effect of acidic functional groups. Base treated electrode enhances the capacity due to the reduction of acidic functional groups. The electrosorption amount of U(VI) on the base treated electrode at -0.3 V corresponds to that of ACF electrode at -0.9 V. Such a good adsorption capacity was not only due to the reduction of shielding effect but also the increase of $OH^-$ in the electric double layer on ACF surface by the application of negative potential.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.393-397
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• 1994

The study was carried out to develop the powdered smoked-dried anchovy products as a natural flavoring substance. The processing conditions, chemical and taste compounds of products were as follows: The raw anchovy were washed, and then boiled 5 minutes in $5{\sim}6%$ NaCl and 1.0% sodium erythorbate solution. Boiled anchovy were smoked in smoking house at $40^{\circ}C$ for 4 hours as the first stage, and then increased temperature up to $80^{\circ}C$ as the second stage, and finally smoked 8 hrs at $80^{\circ}C$ to maintain the moisture content between 9 and 10 percent. The smoked-dried anchovy were pulverized and screened to be 50 mesh of particle size, and finally packed in PET/Al/CPP film bag. The moisture, crude lipid content and salinity of powdered smoke-dried anchovy were 9.4%, 9.6% and 6.9%, respectively. Fatty acid composition of product was mainly consisted of polyenes (43.4%) such as 22 : 6 and 20 : 5, followed by saturates (36.9%), monoenes (19.7%). The principal taste compounds of product were IMP, 466.5 mg/100g; free amino acids such as His, Tau, Pro, Lys, Ala and Glu, 1179.2 mg/100g; non-volatile organic acids such as lactic acid and succinic acid, 617.9 mg/100g; total creatinine, 595.9 mg/100g; small amount of betaine and TMAO. To make a instant soup, it was desirable for taste of products that powdered smoked-dried anchovy were mixed with 20% salt, 4.0% sugar, 3.0% MSG, 1.0% onion powder, 1.0% garlic powder and 1.0% black pepper.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.24-32
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• 1977

According to the chlorous salt method, most of holocellulose whose lignin was removed, was obtained. In extracting xylan from holocellulose by the different densities of alkali, 5% KOH was extracted three times but still there remained part of xylan in it and another composite of hemicellulose and cellulose was obtained. The extraction of 10% and 20% KOH showed a desirable result. Rather than the ordinary method to use a large quantity of ethanol in the precipitation isolation of xylan, the method to use a small quantity of ethanol in adopting the dialysis with cellophane-membrane by condensing density to one tenth, made il possible to extract a high purity xylan in a high retrieving rate. In isolating glucomannan, the residue of 5% KOH extraction contained a large quantity of xylan, the residue of 10% and 24% KOH extraction, also showed the same result and the comparison between glucose and mannose was approximately 1 : 1. The purification of Fehling solution made it possible to obtain comparatively pure xylan but the process of oxidation dissolution was complicated and the retrieving rate was low. This was not a good method. The ethanol titration purified a high purity xylan in a high retrieving rate and was a very excellent purifying method, considering its simple and easy process. These two purifying methods, however, could not completely remove the residue of arabinose. This will be examined and reported later.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.66-72
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• 1983

In order to improve the quality of salted sea mustard, the conditions of blanching, salting, and storage were examined. The process in which sea mustard was blanched for 20 seconds in boiling seawater, soaked in saturated brine solution for 20 hours and then salted for 10 hours by the spreading 10~20% (w/w) of granulated dry salt to obtain the moisture content of about 60% or below, resulted a good color retention of chlorophyll and carotenoid pigments, and organoleptic quality. The shelf-life of the product estimated by 30-40% pigment retention was 50-60days when stored at $4^{\circ}C$ or below.

• Journal of dental hygiene science
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• v.16 no.1
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• pp.70-76
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• 2016

The objective of this study was to fabricate hydroxyapatite (HA) containing titania layer by HA blasting and anodization method to obtain advantages of both methods and evaluated biocompatibility. To fabricate the HA containing titania layer on titanium, HA blasting treatment was performed followed by microarc oxidation (MAO) using the electrolyte solution of 0.04 M ${\beta}$-glycerol phosphate disodium salt n-hydrate and 0.4 M calcium acetate n-hydrate on the condition of various applied voltages (100, 150, 200, 250 V) for 3 minutes. The experimental group was divided according to the surface treatment procedure: SM (simple machined polishing treatment), HA, MAO, HA+MAO 100, HA+MAO 150, HA+MAO 200, HA+MAO 250. The wettability of surface was observed by contact angle measurement. Biocompatibility was evaluated by cell adhesion, and cell differentiation including alkaline phosphatase activity and calcium concentration with MC3T3-E1 cells. The porous titanium oxide containing HA was formed at 150 and 200 V. These surfaces had a more hydrophilic characteristic. Biocompatibility was demonstrated that HA titania composite layer on titanium showed enhanced cell adhesion, and cell differentiation. Therefore, these results suggested that HA containing titania layer on titanium was improved biological properties that could be applied as material for dental implant system.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.735-743
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• 2010

In order to inspect growth responses of Fraxinus rhynchophylla Hance, Koelreuteria paniculata Laxmann, Quercus acutissima Carruther and Ulmus parvifolia Jacquin to NaCl treatment, NaCl solution was treated for four months with 0, 25, 50, 100 and 200 mM concentrations, then survival rate, change of relative growth rate, weight, dry weight and pigment content of leaf were investigated. According to NaCl treatment, pH and EC (electrical conductivity) of soil increased, and growth rates of four tree species fell apparently as treatment time became longer. U. parvifolia had the highest survival rate with 15% in the 200mM treatment, and the other three species withered in the treatment. Relative growth rate, weight and dry weight decreased when NaCl treatment time grew longer. The total chlorophyll declined after it rose to 60 days, and the total chlorophyll and carotenoid of the all species according to NaCl treatment did not change very much. With the result from anlayzing growth responses of four tree species to oxidative stress which occurs during NaCl treatment, U. parvifolia has the highest tolerance, followed by K. paniculata, F. rhynchophylla and Q. acutissima.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.3
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• pp.155-168
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• 2004

Objective: Melatonin, which is secreted by pineal gland play an important role in the regulation of ovarian function via seasonal rhythm and sleep in most mammals. It also has a role in the protection of cells by removing toxic oxygen free radicals brought about by metabolism. In the present study, effects of melatonin on the mouse oocyte maturation were examined using two different culture conditions provided with 5% or 21% oxygen concentration. Material and Method: Immature mouse oocytes were obtained from the ovarian follicles of $3{\sim}4$ weeks old ICR strain mice intraperitoneally injected with 5 I.U. PMSG 44 hour before. Under stereomicroscope, morphologically healthy oocytes with distinct germinal vesicle (GV) were liberated from the graafian follicles and collected using mouth-controlled micropipette. They were then cultured for 17 hour at $37^{circ}C$, 5% $CO_2$ and 21% $O_2$ (95% air) or 5% $CO_2$, 5% $O_2$ and 90% $N_2$. New modified Hank's balanced salt solution (New MHBS) was used as a culture medium throughout the experiments. Effects of melatonin were examined at a concentration of $0.0001{\mu}M$, $0.01{\mu}M$ or $1.0{\mu}M$. For the prevention of spontaneous maturation of immature oocytes during culture, dibutyryl cyclic AMP (dbcAMP) and/or hypoxanthine were included in the medium. Results: Under 21% oxygen condition, oocytes cultured in the presence of $0.01{\mu}M$ melatonin showed a significantly higher maturation rates, in terms of germinal vesicle breakdown (95.0% vs 89.0%) and polar body formation (88.1% vs 75.4%), compared to those cultured with $0.0001{\mu}M$ or $1.0{\mu}M$ melatonin. However, no difference was observed in oocytes cultured under 5% oxygen whether they were treated with melatonin or not. In the presence of $0.01{\mu}M$ melatonin, oocytes either cultured under 21% or 5% oxygen exhibited no difference in the polar body formation (85.6% vs 86.7%). However, in the absence of melatonin, oocytes cultured under 21% oxygen exhibited lower polar body formation (74.7%). When oocytes were cultured in the presence of dbcAMP alone or with varying concentrations of melatonin, those treated with both compounds always showed better maturation, i.e., germinal vesicle breakdown and polar body formation, compared to those cultured with dbcAMP alone. At the same concentration of melatonin, however, oocytes exposed to 21% oxygen showed poor maturation than those to 5% oxygen. Similar results were obtained from the experiments using hypoxanthine instead of dbcAMP. Conclusion: Based upon these results, it is suggested that melatonin could enhance the meiotic maturation of mouse oocytes under 21% oxygen concentration, and release oocytes from the meiotic arrest by dbcAMP or hypoxanthine regardless of the concentration of oxygen, probably via the removal of oxygen free radicals.

• Journal of Navigation and Port Research
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• v.35 no.5
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• pp.393-400
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• 2011

The residential complexes in waterfront provide the residents with pleasantness and comfort with their scenety and view in the surrounding watersides. However, it is currently true that there has little been established any designing plan utilizing the environmental characteristics of the waterfront. In this study, a survey was conducted on the residents of a Japanese waterfront. in Nishimiyahama and Lake Biwa, and conducted a comparative and analytic investigation regarding water-friendly activities, residents' consciousness of the housing environment, and reasons for the choice of residenve. From the results, we were able to obtain some suggestive points resulting from the differences of the aforementioned. We also fully comprehended that there are some issues and needs for solution for the environmental characteristics in the waterfront as well as for the damage incurred by salt breeze and insects. In addition, we realized that scenery and view toward watersides are becoming the important factors in the residents' consciousness regarding the housing environment. In case of planning housing complexes located in the waterfront, we keenly understood that "the size of a room", "ventilation", "view and daily lighting", and "securing privacy" are having effects on the residents' consciousness of their housing.

• Membrane Journal
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• v.25 no.6
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• pp.496-502
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• 2015

Facilitated transport is one of the possible solutions to simultaneously improve permeability and selectivity, which is challenging in conventional polymer-based membranes. Olefin/paraffin separation using facilitated transport membrane has received much attention as an alternative solution to the conventional distillation process. Herein, we report olefin separation composite membranes based on the polymer blends containing $AgBF_4/Al(NO_3)_3$ mixed salts. Free radical polymerization process was used to synthesize an amphiphilic graft copolymer of poly(dimethyl siloxane)-graft- poly(ethylene glycol) methyl ether methacrylate (PDMS-g-POEM). In addition, poly(ethylene oxide) (PEO) was introduced to the PDMS-g-POEM graft copolymer to form polymer blends with various ratios. The propylene/propane mixed-gas selectivity and permeance reached up to 5.6 and 10.05 GPU, respectively, when the PEO loading was 70 wt% in polymer blend. The improvement of olefin separation performance was attributed to the olefin facilitating silver ions as well as the highly permeable blend matrix. The stabilization of silver ions in the composite membrane was achieved through the introduction of $Al(NO_3)_3$ which suppressed the reduction of silver ions to silver particles.