• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.4
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• pp.179-191
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• 2018

In order to determine the distribution characteristics of the heavy metals in surface sediments of the eastern Yellow Sea, heavy metal concentrations (Cu, Pb, Zn, Cd, Cr, Mn, As, Ni, Co, Li, Fe and Al) together with grain size and total organic carbon (TOC), were analyzed. The concentrations of all heavy metals, with the exception of Pb, Mn and As in some stations, were relatively high in the central area of the Yellow Sea and tended to decrease toward the Korean coast. A significant relationship between grain size and concentrations of heavy metals suggested that they were mostly controlled by quartz dilution effect. However, at some stations, Pb, Mn and As exhibited different distribution patterns. For Pb, the differences were caused by petrogenetic influences (feldspar) in coarse-grained sediments. In the case of Mn, biogenetic influences ($CaCO_3$) affected distribution patterns. As was distributed differently because of the existence of a heavy mineral (pyrite). A comparison with previous data (collected in 2000) shows that the heavy metal concentration in the eastern Yellow Sea has not increased over the past fifteen years. The sedimentary environment of dumping sites in the Yellow Sea has not been significantly improved during this period. The results of the pollution assessment revealed that the concentrations of heavy metals in the study area were lower than lower criteria (TEL, MSQ-1) in Korean and Chinese sediment quality guidelines. The enrichment factor (EF), geo-accumulation index ($I_{geo}$) and ecological risk index (ERI) of Cu, Pb, Zn and Cr were higher in the central area of the Yellow Sea.

• Journal of Life Science
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• v.31 no.3
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• pp.314-320
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• 2021

In the present study, we investigated the effect of photoperiod and water temperature on the gonadosomatic index (GSI), histological stage of the testes, and plasma levels of sex steroid (testosterone, T; 11-ketotestosterone, 11-KT) hormones in cultured male small yellow croakers (Larimichthys polyactis). In a photoperiod experiment, small yellow croakers were reared under a natural photoperiod (NP, 10L:14D-11L:13D), long photoperiod (LP, 14L:10D), and short photoperiod (SP, 10L:14D) at 17℃ for 90 days. The GSI was significantly higher in the LP group than in the other groups at 30 and 60 days. The plasma 11-KT levels were significantly higher in the LP group than in the other groups at 30 days. In a water temperature experiment, small yellow croakers were reared under natural water temperature (NT, 19.1-15.0℃), or at 17℃, 21℃, or 25℃ under a LP (14L:10D) for 60 days. The GSI was significantly lower for the 25℃ group than for the other groups at 30 and 60 days. The plasma 11-KT levels were significantly lower for the 25℃ group than for the other groups at 60 days. Therefore, the sexual maturation of cultured male yellow croakers was promoted by LP and inhibited at water temperatures above 25℃. These findings suggest that the sexual maturation of cultured male small yellow croakers is controlled by both the photoperiod and the water temperature.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.8-14
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• 2011

This study was conducted to investigate the effect of age of transplants, propagated by cutting, of two cut rose (Rosa hybrida Hort.) cultivars on their subsequent growth and yield in an effort to develop an efficient cutting propagation method for domestic rose cultivars. Two cultivars used in this study were a standard type 'Pink Aurora' and a spray type 'Yellow King'. Cuttings were prepared as single node cuttings each with a five-leaflet leaf and were stuck in rockwool cubes ($5cm{\times}5cm{\times}5cm$, UR, Korea) at two different dates. Cuttings rooted for either 30 (stuck on Jan. 20, 2009) or 48 days (stuck on Jan. 2, 2009) were transplanted into a rockwool slabs ($10cm{\times}15cm{\times}100cm$, UR, Korea) on the same date, 18 Feb. 2009. Plant growth and cut flower quality were investigated for two successive harvests during the period of Jan. to July in 2009. In both cultivars, 48 days old plants showed some growth of the shoot and root before transplanting. However, in the case of 30 days old plants before transplanting no noticeable growth of the shoot and root was obserable in 'Pink Aurora', while only shoot growth, but not root growth to the bottom of the rooting medium, was observed in 'Yellow King'. This suggested cultivar-specific responses that in this experiment a spray type 'Yellow King' showed greater growth rate during the rooting stage than a standard type 'Pink Aurora'. In the measurement of growth and cut flower yield after transplanting, the 48 days old standard type 'Pink Aurora' produced greater number of cut flowers per plant than 30 days old plants, whereas their mean stem fresh weight was recorded smaller than that of the 30 days old plants. For 'Yellow King', 30 days old plants showed greater stem length, flower width, number of five-leaflet leaves per stem, stem fresh weight, and number of cut flowers per plant than 48 days old plants. Therefore, growth and yield were significantly affected by cultivar and age of the rooted cutting, and additional research is needed on the effect of age of rooted cuttings in more cultivars.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.803-811
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• 2003

This study compared the physicochemical characteristics of yellow pigments in domestic and imported yellow croakers during distribution and storage. The croaker is generally adulterated by mixed color product of red and yellow pigment. This study found that the yellow pigment was stable during pH and temperature changes, but the red pigment was less stable than the yellow pigment. As for the light effect on the yellow pigment and the red pigment, there was no change in the remaining rate of the pigment stored in a dark place. The moisture content decreased according to the storage period, and the width of changes was large in the order of croaker stored at $5^{\circ}C$, croaker stored at $15^{\circ}C$ and dried croakers. The yellowness value of the abdomen of the adulterated white croaker did not show any large difference at the initial stage and for a storage period of 10 days at $5^{\circ}C$. However, the yellow croakers showed a decreasing trend according to the storage period at $15^{\circ}C$. The croaker can be generally adulterated by a mixed color of red and yellow pigment. For the texture change in accordance with the storage condition of the croakers, both the yellow and white croakers showed a gradually increasing trend of hardness when stored at $5^{\circ}C$ and $15^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.119-124
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• 2008

Storage conditions of selling mungbean sprouts should affect their marketability. The study was done to examine the effect of light quality (blue, green, yellow, red, far-red) on greening period, shape, fresh and dry weights of mungbean (cv. Zhong Lu 1) sprouts for 5 days to get some information on designing their various polyethylene envelops with different colors. Periods taking to green were 2 to 3.5 days in blue, red and far-red lights but longer than 6 days in green and yellow lights. Yellow lights had the longest total length adding hypocotyl and root, and blue light did the widest hypocotyl diameter while all light treatments showed similar lateral roots for the period. Total fresh and dry weights were the highest in red light but the least in far-red light. Their lengths and weights in green and yellow lights showing the longest periods for their greening declined with increased storage periods but showed no difference between them, meaning that the envelops should be designed mainly by green and yellow colors.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.316-324
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• 2005

The objectives of this study were to examine effect of ion chip and yellow soil on the growth and physicochemical characteristics of soybean sprouts. The weight and length increased rapidly in soybean sprouts cultivated for 4 days and then the increases slowed. Ascorbic acid increased rapidly after day 6 in soybean sprouts cultivated with ionized water (I.W), $1.0\%$ yellow soil in tap water (T.W+l.0) and $1.0\%$ yellow soil in ionized water (I.W+l.0). The detected content of minerals such as Mg, Ca, K and Fe in soybean sprouts was higher than other minerals. Iron content was the highest in soybean sprouts cultivated by I.W+1.0. The detected levels of glutamic acid in soybean sprouts cultivated for 4 days with ionized water was higher than in those grown with tap water. In all soybean sprouts, nucleotides such as UMP, CMP, AMP, Hx and soluble free sugars like sucrose, raffinose, stachylose were detected, and the levels of UMP were found to be the highest among nucleotides and sucrose among free sugars.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.6
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• pp.286-297
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• 2018

In the present study, wave measurements at KOGA-W01 were analyzed and then the numerical wind waves simulations have been conducted to investigate the characteristics of wind waves in the Yellow sea. According to the present analysis, even though the location of the wave stations are close to the coastal region, the deep water waves are prevailed due to the short fetch length. Chun and Ahn's (2017a, b) numerical model has been extended to the Yellow Sea in this study. The effects of tide and tidal currents should be included in the model to accommodate the distinctive effect of large tidal range and tidal current in the Yellow Sea. The wave hindcasting results were compared with the wave measurements collected KOGA-W01 and Kyeockpo. The comparison shows the reasonable agreements between wave hindcastings and measured data, however the model significantly underestimate the wave period of swell waves from the south due to the narrow computational domain. Despite the poorly prediction in the significant wave period of swell waves which usually have small wave heights, the estimation of the extreme wave height and corresponding wave period shows good agreement with the measurement data.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.539-546
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• 2008

This study was conducted in order to investigate the effects of maesil extract on medium and cake flour using the falling number and RVA tests, as well as farinography, and alveography. The maesil extract were added on the medium and cake flour bases, 3% and 5% each. The falling numbers of the medium and cake flour with maesil extract were increased due to alteration of the protein in the flour. Analysis of the RVA characteristics showed that the addition of maesil extract did not have a significant effect on the initial pasting temperature. Peak viscosity, holding strength, final viscosity, and the breakdown and setback values of the medium flour were not consistent, but those of the cake flour decreased. Farinography demonstrated that the addition of maesil extract decreased water absorption and improved the stability of the medium and cake flour. The characteristics of the alveogram showed that the addition of maesil extract increased the extensibility and swelling index. Based on the experimental data, the processing rheology may be good when using maesil extract to make yellow layer cake.

• Textile Coloration and Finishing
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• v.11 no.2
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• pp.38-45
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• 1999

Natural red colorants were extracted from Phytolacca americana Linne by using 50% ethanol solution at room temperature for 12 hours. The colorant components were partially purified as yellow and deep red colorants by thin layer chromatography. Natural red colorants were consisted of major water-soluble red colorant, having maximum absorbance at 538nm and alcohol-soluble yellow colorant, having maximum absorbance at 664nm. Concentration of red colorants were calibrated by the equation of dye(mg/ml) $A_{538nm}\times{1.284}$. Red colorants were changed to yellow at extreme alkali pH and repaired 55% color intensity by neutralization of pH and stabled below $55^\circ{C}$. Dyeability of red colorants against wool fabrics was mainly operated by red pigment having 538nm absorbance without big color differences. Below $55^\circ{C}$, color differences $(\Delta{E}^*_{ab})$ were not changed in spite of big difference of chroma$(c^*)$, having higher scores at higher temperature. The effect of mordants were not drastically changed parameters of color difference without copper ion. Citric acid was big changes of color difference$(\Delta{E}^*_{ab})$ in spite of similar chroma$(c^*)$ values. From these experimental results, red colorants from Phytolacca americana Linne is available for wool fabric dyeing.

• Ocean and Polar Research
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• v.29 no.2
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• pp.113-121
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• 2007

The sound wave in the sea propagates under the effect of water depth, sound speed structure, sea surface roughness, bottom roughness, and acoustic properties of bottom sediment. In shallow water, the bottom sediments are distributed very variously with place and the sound speed structure varying with time and space. In order to investigate the seasonal propagation characteristics of low-frequency sound wave in the Yellow Sea, propagation experiments were conducted along a track in the middle part of the Yellow Sea in spring, summer, and autumn. In this paper we consider seasonal variations of the sound speed profile and propagation loss based on the measurement results. Also we quantitatively investigate variation of bottom loss by dividing the propagation loss into three components: spreading loss, absorption loss, and bottom loss. As a result, the propagation losses measured in summer were larger than the losses in spring and autumn, and the propagation losses measured in autumn were smaller than the losses in spring. The spreading loss and the absorption loss did not show seasonal variations, but the bottom loss showed seasonal variations. So it was thought that the seasonal variation of the propagation loss was due to the seasonal change of the bottom loss and the seasonal variation of the bottom loss was due to the change of the sound speed profile by season.