• Food Science and Preservation
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• v.24 no.2
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• pp.168-180
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• 2017

This study was performed to determine the rapid thawing method for reducing the thawing time of frozen pork loins and to examine the effects of supercooling on the microbiological, physicochemical, and sensory qualities of fresh and frozen-thawed pork during storage at -1.5, 4, and $15^{\circ}C$. Forced-air thawing at $4^{\circ}C$ was the most time-consuming process, whereas radio frequency thawing time was the shortest by dielectric heating. The supercooling storage temperature was chosen to be $-1.5^{\circ}C$ because microstructural damages were not observed in the pork sample after cooling at $-1.5^{\circ}C$ for 24 h. Fresh or frozen-thawed pork loins stored at $-1.5^{\circ}C$ had lower drip loss and total volatile base nitrogen, thiobarbituric acid-reactive substance, and Hunter b* levels than loins stored at 4 and $15^{\circ}C$. In addition, the least degree of increase in preexisting microorganisms counts of the fresh or frozen-thawed pork loin samples was obtained during supercooled storage at $-1.5^{\circ}C$. Sensory quality results of fresh and frozen-thawed pork loin samples stored at $-1.5^{\circ}C$ showed higher scores than the samples stored at 4 and $15^{\circ}C$. These data indicate that supercooling at $-1.5^{\circ}C$ in the meat processing industry would be effective for maintaining the quality of pork meats without ice crystal nucleation and formation.

• Clean Technology
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• v.13 no.1 s.36
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• pp.54-63
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• 2007

Even traces of CO in the hydrogen-rich feed gas to proton exchange membrane fuel cells (PEMFC) poison the platinum anode electrode and dramatically decrease the power output. In this work, a variety of catalytic materials consisting of $Cu/Ce_xZr_{1-x}O_2$, (x = 0.0-1.0) were synthesised, characterized and tested for CO oxidation and preferential oxidation of CO (PROX). These catalysts prepared by hydrothermal and deposition-precipitation methods. The catalysts were characterized by XRD, XRF, SEM, BET, $N_2O$ titration and oxygen storage capacity (OSC) measurement. The effects of composition of the support and degree of excess oxygen were investigated fur activity and $CO_2$ selectivity with different temperatures. The composition of the support markedly influenced the PROX activity. Among the various $Cu/Ce_xZr_{1-x}O_2$ catalysts having different composition, $Cu/Ce_{0.9}Zr_{0.1}O_2$ and $Cu/Ce_{0.7}Zr_{0.3}O_2$ showed the highest activities (>99%) and selectivities (ca.50%) in the temperature range of $150{\sim}160^{\circ}C$. It was found that by using of $Ce_xZr_{1-x}O_2$ mixed oxide support which possesses a high oxygen storage capacity, oxidation-reduction activity of Cu-based catalyst was improved, which resulted in the increase of catalytic activity and selectivity of CO oxidation in excess $H_2$ environments.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.34-39
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• 2001

The purpose of this study was to examine physical properties of the addition of green tea powder on bread flour and dough rheology of white pan bread. Three levels(0.1, 0.5 and 1.0% ) of each green tea powder with bread flour were tested for their effects in dough mixing using rapid disco analyzer, alveogram and farinogram. Addition of green tea powder tended to reduce initial pasting temperature and increase peak viscosity, break down and set back. L(extensibility) and G(swelling index) value in alveogram showed decrement with increasing green tea powder. These meant that the volume of white pan bread would show same tendency. The use of green tea powder increased consistency and water absorption of the bread flour but decreased development time, salability and degree of softening on farinogram. White pan bread with green tea powder had higher value of hardness and springness than without it. Sensory evaluation determined that the white pan bread with 0.5% green tea powder had the highest score.

• Journal of Wetlands Research
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• v.4 no.1
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• pp.63-85
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• 2002

This study was carried out to provide basic data for water environmental control and conservation, and to elucidate monthly water environmental factor, phytoplankton flora and dominant species that each stations was maked a selection of a sites by represent 3 branch-river in the Taejon area from Nov. 1997 to Dec. 1998. Range of water temperature was $2.4^{\circ}C{\sim}30.9^{\circ}C$(means of $16.02^{\circ}C{\sim}18.92^{\circ}C$), pH was 7.1~10.4(means of 7.40~8.68). BOD was generally under $5mg/{\ell}$ except Gap-chon kyo in Nov. and COD was measured highly by interfer of men at the each sites. Especially, occasion of Gap-chon kyo, data was estimated about 3~13 times higher than another sites. DO was showed 1.03~10.43ppm, SS was showed $1.0{\sim}120.0mg/{\ell}$ TN was that, upper stream was 0.63ppm, middle was 0.35ppm and then lower was 0.44ppm, upper stream was higher than lower. TP was at upper stream 0.03ppm, middle 0.05ppm, lower 0.06ppm, lower stream was higher than another. The phytoplankton flora was identified as total 230 taxa composed of 7 classes, 18 oders 35 families, 75 genara, 184 species, 42 virieties, 4 forms. There are composed of that, Chlorophyceae 94 taxa(40.9%), Bacillariophyceae 66 taxa(28.8%), Euglenophyceae 39 taxa(17.0%), Cyanophyceae 24 taxa(10.4%), Chrysophyceae 4 taxa(1.7%), Rhodophyceae 2 taxa(0.8%) Xanthophyceae 1 taxa(0.4%), composition of Spesies of each sites was Gapchon-kyo 119, Wonchon-kyo 94, Gasuwon-kyo and Mannyon-kyo 87, Ochung-kyo 78, Hyunam-kyo and Suchim-kyo 77, Moonchang-kyo 70 taxa and Sansung-kyo 58 taxa. Number of species was showed tendency of increase lower stream. Taejon-chon and youdung-chon and at the sites of confluence were presented Synedra ulna and Diatom vugare like bacillariophyceae, Gap-chon was dominated variously Oscillatoria princeps and chlorophyceae, confluence of 3 branch-river was presented Euglenophyceae.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.423-435
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• 1984

The reproductive cycle of the small filefish, Rudarius ercodes was investigated based on the annual variations of gonadosomatic index(GSI) and hepatosomatic index(HSI) by electronic and photic microscophy. The specimens used were collected at the coastal area of Benden island, Sizuokagen, Japan, from September 1982 to August 1983. GSI began to increase from March, starting season of longer daylength and higher water temperature, and reached the maximum value between June and August. It began to decrease from September with the lowest value appearing between November and February without any evident variation. The annual variations of HSI were not distinct in male filefish and were negatively related to GSI in female : HSI decreased in the summer season when the ovary was getting mature and reached the maximum in the winter season when the ovary was getting retrogressive. The ovary consisted of a pair of saccular structure with numerous ovarian sacs branched toward the median cavity. Oogonia divided and proliferated along the germinal epithelium of the ovarian sac. Young oocytes with basophile cytoplasm showed several scattering nucleoli along the nuclear membrane. when the oocytes growing to about 300 ${\mu}m$, nuclear membrane to disappear with nucleus migrating toward the animal pole. The regions of protoplasm were extremely confined within the animal hemisphere in which most of cytoplasms were filled with yolk materials and oil drops. After ovulation, residual follicles and growing oocytes remaining in the ovarian sacs degenerated. But perinucleatic young oocytes without follicles formed were not degenerated, and growing continuously still in the next year. Mitochondria and endoplasmic reticula in the cytoplasm remarkably increased with oocytes maturing and yolk accumulating. Those were considered to be functionally related to the yolk accumulation. Five or six layers of possible vitellogenin, oval-shaped disc structures with high electron density, appeared in the apex of follicular processes stretching to the microvilli pits of mature oocytes. Testis consisting of a pair of lobular structures in the right and left were united in the posterior seminal vesicle, Cortex of testis was composed of several seminiferous tubules, and medulla consisting of many sperm ducts connected with tubules. Steroid hormone-secreting cells with numerous endoplasmic reticula and large mitochondria of well developed cristae were recognized in the interstitial cells of the growing testis. Axial filament of spermatozoon invaginated deeply in the central cavity of the nucleus and the head formed U-shape with acrosome severely lacking, mitochondria formed large globular paranuclei at the posterior head, and microtubular axoneme of the tail represented 9+9+2 type. The annual reproductive cycles could be divided into five successive stages : growth(March to July), maturation(May to September), Spawning(mid May to early October) and resting stages(October to February). The spawning peak occurred from June to August.

• Journal of the Korean Vacuum Society
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• v.5 no.4
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• pp.371-376
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• 1996

Au films with a thickness around 1600 $\AA$ were deposited onto glass at room temperature by ion beam sputtering with a 5 cm cold-hollow ion gun at pressure $1\times 10^{-6}-1\times 10^{-5}$ Torr. Irradiation of the Au deposited samples was carried out at pressure of $7\times 10^{-6}$ Torr. For the sputter depositions, $Ar^+$ ion energy was 1 keV, and the current density at the substrate surface was 15 $\mu$A/$\textrm{cm}^2$. Effects of 1 keV $Ar^+$ ion dose($I_d$) between $1\times 10^{16}\; and\;2\times 10^{17}\;Ar^+\textrm{cm}^{-2}$on properties such as crystallinity, surface roughness and adhesion, etc. of the films have been investigated. The Au films sputtered by $Ar^+$ ion beam had only (111) plane and the X-ray intensity of the films decreased with increase of $I_d$. The thickness of Au films reduced with Id. $R_{ms}$ surface roughness of the films increased from 16 $\AA$ at as-deposited to 1118 $\AA$ at ion dose= $2\times 10^{17}\;Ar^+\textrm{cm}^{-2}$. Adhesion of Au film on sputtered at $I_d$= $2\times 10^{17}\;Ar^+\textrm{cm}^{-2}$ was 9 times greater than that of Au film with untreated, as determined by a scratch test.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1248-1256
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• 2014

The purpose of this study was to investigate the mechanisms of behind $SO_2$ formation and elevated cause of reducing power in purple bamboo salt (PBS) along with an analysis of physicochemical properties, content of sulfur compounds, oxidation reduction potential (ORP), mineral contents of salt type (MSS, mudflat solar salt; BS, bamboo salt), and addition of raw bamboo (RB). $SO_2$ content of 630 ppm was detected in PBS. $SO_2$ was not detected in MSS, BS, or RB, whereas $SO_2$ (782 ppm) from $K_2SO_4$ was detected after heating a NaCl, KCl, $MgCl_2$, $MgSO_4$, MgO, $CaCl_2$, $K_2SO_4$, and $FeSO_4$ with RB. $SO_2$ content of BS increased with baking time, and it originated from BSRB1 (13.88 ppm) to BSRB4 (109.13 ppm). $SO_3{^{2-}}$ originated only from MSSRB4 and BSRB2~BSRB4. Sulfate ion content decreased along with increasing $SO_2$ and sulfite ion contents. ORP increased with baking time of MSS and BS, and it was present at higher levels in BSRB4 (-211.40 mV) of BS than MSS. Insoluble content was higher in BS than MSS. Further, Ca, K, and Mg ion contents decreased in MSS and increased in BS with baking time. BSRB4 had 1.4 fold higher levels of Ca, 1.5 fold higher levels of Mg, and 1.8 fold higher levels of K than BS. Li, Al, Mn, Fe, and Sr in MSS as well as Al, Fe, and Ni in BS increased with baking time. Anions (Cl, $NO_3$, and Br) and heavy metals (Pb, Cd, Hg, and As) between MSS and BS were not significantly different. These results suggest that the reducing power of BS was due to $SO_2$ and sulfite ion. To increase the amounts of these compounds and reducing power, higher melting temperature and longer baking time are necessary along with BS, which is created by the addition of RB to roasted salt.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.302-311
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• 2018

Using cylindrical paper pot nursery method, three kinds of commercial tomatoes 'Dafnis', 'DOTAERANG DIA' and 'Maescala' were grafted onto a commercial rootstock 'B blocking'. From 10 to 40 days after graft-take, growth traits of seedlings were investigated by 0.5, 1.0 and 2.0S treatments of standard nutrient solution(S) for seedling growth, and top to root ratio(TRR), compactness(CP) and Dickson Quality Index(DQI) were calculated. Two weeks after transplanting of the seedlings under three different night temperature targeting to 10, 15, and $25^{\circ}C$, which were not precisely controlled, the relative growth rate (RGR) was investigated. The quantitative growth traits of grafted seedlings increased with increasing fertilizer concentration, and various range of seedling size could be produced. Compactness and DQI were significantly regressed (Adj $R^2=0.9480$). Short-term RGR after transplanting was higher at 1.0S treatment of standard nutrient solution at the seedling age of 30 days and 40 days after graft-take(DAGT). DQI and RGR were significantly regressed linearly at respective fertigation strength. Specially the diminishing slope of RGR was lower at 1.0S fertigation strength with the increase of DQI than others. The results indicate that DQI could be applied as a quality index of grafted tomato seedlings and the relation analysis between DQI and short-term RGR also could be used to determine the good quality seedlings of grafted tomato grown in cylindrical paper pot.

• The Korean Journal of Malacology
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• v.32 no.4
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• pp.279-287
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• 2016

NIFS conducted a feasibility study on the bay scallop Argopecten irradians aquaculture in the test site of Dongsanri, Yangyang-gun, Gangwon-do in June 2015. The transplantation for the test was also carried out in June. The average shell length was $5.79{\pm}0.6mm$ at the time, $15.83{\pm}0.8mm$ in July, $39.40{\pm}0.7mm$ in September, $55.72{\pm}5.8mm$ in November and $59.67{\pm}1.7mm$ in December. At the time of transplantation, the average shell height was $6.06{\pm}0.7mm$, and it grew to $16.40{\pm}0.9mm$ in July, $53.16{\pm}5.2mm$ in November and $55.80{\pm}2.9mm$ in December. Total weight was $0.78{\pm}0.5g$ in July but increased to $24.25{\pm}4.2g$ in November and $26.06{\pm}4.3g$ in December. The daily growth rate of shell length(DGR) was 0.33 mm / day in June, 0.43 mm / day in September and 0.13 mm / day in November. DGR of weight was 0.20 g / day in June, 0.27 g / day in September, 0.06 g / day in November. The relative growth of shell length and shell height was y = 0.9132x and $R^2=0.9923$. As a result, it was proved that bay scallop aquaculture is possible in Gangwon province, the northern part of the East Sea. This will definitely increase the income of fishermen by enabling them to culture more aquaculture species than the single large Patinopecten yessoensis in the region.

• Journal of Mushroom
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• v.11 no.3
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• pp.154-158
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• 2013

To develop a new variety of oyster mushroom(Pleurotus ostreatus), parental strains was selected by the method of Mon-Mon crossing between monokaryotic strains derived from ASI 2596(Suhan No.3) and ASI 2782(Black pileus mutant). The SB-73(ASI 2596-11 x 2782-8) was shown the best cultural characteristics, selected to be a new variety and named as 'Dagul'. The 'Dagul' was formed incompatibility line distinctly in the confrontation growth of parental strains Suhan No.3 and ASI 2782. The optimum temperature for mycelial growth, fruiting body development and pH arrange were $25{\sim}30^{\circ}C$, $14{\sim}17^{\circ}C$ and pH5~8, respectively. Fruiting body production per bottle was about $68.0{\pm}24.1$ g which is almost 115% quantity compared to that of other variety Suhan No.3. And also the stipe is long and individual generation is multiple. Analysis of the genetic characteristics of the new variety 'Dagul' showed different DNA bands as that of the control strains, Suhan No.3 and ASI 2782, when RAPD(Random Amplified Polymorphic DNA) primers URP7 and Rcb1 were used. This new variety 'Dagul' of oyster mushroom is characterized by multiple of individual generation and the stipe is long. We therefore expect that this new strain will increase of the income by cultivation of field.