• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.25-32
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• 1998

To characterize the growth environment, inorganic composition and morphological chracteristics of leaves of Korean tea plant, soil and tea leaf samples were collected from 15 locations and analyzed. The chemical characteristics of soils were in range of pH 4.09~6.15, OM 23.9~72.6g/kg, available phosphate less than 300mg/kg, K $0.8{\sim}2.5cmol^+/kg$, Na $tr{\sim}0.17cmol^+/kg$, Ca $1.0{\sim}6.2cmol^+/kg$, and Mg $0.3{\sim}2.1cmol^+/kg$. The contents of Ni. Cr, Zn. Cu, Pb, and Cd were at the level less than natural content in upland soil. Most of the sample soils were sandy loamy and loamy texture. The native tea plants were mainly grown in bamboo thicket or in forest. The leaf sizes of tea plants were $6.85{\pm}1.75{\times}2.6{\pm}0.5cm$, lateral vein number $14.2{\pm}2.7$, and crenated number $58.5{\pm}11.2$, and the leaf color was thin to dark green. The contents of $NH_4{^+}$, $Na^+$, $K^+$, $Mg^{2+}$ and $Ca^{2+}$ in tea leaves were in range of 30.5~47.7, 45.5~164.5, 16,998~25,431, 1.590~2,392 and 1,085~1,958mg/kg, respectively. The contents of $F^-$, $Cl^-$, $NO_3{^-}$, $PO_4{^{3-}}$ and $SO_4{^{2-}}$ were in range of 21.2~63.2, 126.4~257.9, 108.5~185.9, 1,270~1.819, and $954{\sim}1,670mg/kg$, respectively. The leaf size of native tea plant grown widlly in Shunchun Changchun-ri, Hwasun Ssangbongsa, Kuryoi Chonunsa, Bosong Daewonsa and Namhae Boriam was as large as those of Yabukita. Japan cultiver, grown at Kangjin Jangwon tea field.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.15-21
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• 2001

This study was conducted to investigate the immunomodulatory activities of proteoglycan extracted from cultured mycelia of Ganoderma lucidum IY009. The proteoglycan contained two polymer peaks, one was the higher MW peak of 2,000 kD and the other was low peaks of 12kD. To understand the part of strong pharmaceutical activity between two peak, the proteoglycan was separated by ultrafiltration and column chromatography and then examined the various pharmaceutical effects. High molecular weight fraction possesing high content of ${\beta}-linked$ glucan was exhibited high antitumor activity, against sarcoma 180 bearing ICR mouse. And also, anticomplementary activity was highly observed in high molecule fraction than low it fraction. When the raw 264.7 and murine peritoneal macrophage treated with low fraction, high fraction and other stimuli. The activities inducing tumor necrosis factor of the high factions were $2.2{\sim}2.5$ times stronger than that of low fraction.

• The Korean Journal of Quaternary Research
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• v.16 no.1
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• pp.1-16
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• 2002

A total of 4 muddy sediment samples collected from the Central Yellow Sea were analyzed for chemical composition. The results are compared with the previously published Huanghe, Changjiang and Keum River geochemical data in order to understand provenance and sedimentation of fine-grained mud, and the sediment accumulation rates estimated. The sandy sediment facies is distributed in the eastern area, a patch of fine-grained mud exists in the western central prat, and the sandy mud and clay sedimentary facies shot. north to south zonal distribution in the central region. The content of calcium carbonate ranges from 2.8 to 10.5%, and its distributional trends to be more concentrated on the western muddy sediments near toward the China side rather than on the eastern sandy sediments. The accumulation rates obtained using Pb-210 geochronologies for the muddy sediments in the Central Yellow Sea showed ranges from 0.21 to 0.68 cm/yr or 0.176 to 0.714 g/$\textrm{cm}^2$. yr. The sedimentation rate from core CY96010 located in the eastern near side of Shandong Peninsula which is affected by the Huanghe River shows 0.68 cm/yr or 0.714 g/$\textrm{cm}^2$ . yr. The sediment cores CY96008 and CY96002 in the Central Yellow Sea, the estimated of sediment accumulation rates shows 0.21~0.23cm1yr or 0.176~0.220 9/$\textrm{cm}^2$.Vr respectively, which are much lower than above samples. These indicate that the muddy sediments in central area of the Yellow Sea may have received influence of the sediment discharge from the Huanghe River. The concentrations of Ca, Na, Sr, Ho, La, Tb, Ta and Ca/Ti ratio of the muddy sediments in the Central Yellow Sea are higher than those of the Changjiang sediments and lower than those of the Huanghe sediments. However, these element values showed similar concentration patterns than those of the Huanghe sediment. The element contents such as Fe, Ti, Nl, Co, Cr, Cu, Pb, Sc, Ce, Nd, Sm, Eu, Cd and Dy in the study area are higher than those of the Huanghe sediments and lower than the Changjiang River sediments, but these values showed close to resemblance content trends those of the Changjiang sediment. The concentration of Mn, K and Sr in sediments of the study area are similar to those of the Keum River and eastern Yellow Sea sediment. They are rich in Zn, Rb, Cd, U, Cs and Li than those of the other comparison legions. Therefore, the terrigenous materials sources of the muddy sediment in the Central Yellow Sea comes mainly from Huanghe River in the past and present, and also have party derived from the Changjiang and Keum River, while the biological deposit in this area are carried by the Yellow Sea Warm Current.

• Korean Journal of Environment and Ecology
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• v.24 no.4
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• pp.426-435
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• 2010

The present study attempts to compare the soil chemical characteristics and biological activities (i.e. microbial biomass and soil enzyme activities), and litter decomposition rate of Arundinella hirta and Miscanthus sinensis var. purpurascens) collected from serpentine and non-serpentine sites by litter bag techniques at serpentine and non-serpentine field experiment sites over a 9-month period. The serpentine soil showed higher pH and soil alkaliphosphatase activity, and lower soil dehydrogenase and urease activities than the non-serpentine soil. Microbial biomass-N at the serpentine soil was larger than the non-serpentine soil, although the microbial biomass-C and microbial biomass-N represented no significant difference between serpentine and non-serpentine soil. These results suggest that the larger microbial biomass-N caused the lower C/N in serpentine soil. At the end of the experiment, the litter samples of A. hirta and M. sinensis collected from serpentine soil revealed a 39.8% and 38.5% mass loss, and the litter sample from non-serpentine soil also showed a 41.1% and 41.7% mass loss at the serpentine site. On the other hand, at the non-serpentine site, 42.2%, 37.4%, and 46.8%, 44.8% were respectively shown. These results demonstrate that the litter decomposition rate is more intensely affected by the heavy metal content of leaf litter than soil contamination. Moreover, the litter collected from the serpentine soil had a lower C/N, whereas the litter decomposition rate was slower than the litter from the non-serpentine soil, because the heavy metal inhibition activities on the litter decomposition process were more conspicuous than the effect of litter qualities such as C/N ratio or lignin/N. The nutrient element content in the decomposing litter was gradually leached out, but heavy metals and Mg were accumulated in the decaying litter. This phenomenon was conspicuous at the serpentine site during the process of decomposition.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.469-478
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• 2004

Pig slurry, urine and fermented liquid manure were evaluated measuring electrical conductivity (EC), dry matter (DM) contents and other components. Samples were collected during a period from February to April, 2001: slurry samples from 70 storage tanks, urine samples from 19 and 20 fermented liquid manure samples from 109 pig farms in Jeju. Samples were analyzed for pH, EC, DM, $NH_4$-N, K, P, Ca, Mg, Na, BOD, S-S, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and OM. Relationships between EC or DM and various mineral and $NH_4$-N contents were examined using linear regression. EC, DM, all mineral contents and $NH_4$-N were higher in slurry samples than in urine or fermented liquid manure. EC, $NH_4$-N, Ca, Mg and Na concentration was similar in urine and fermented liquid manure, but K and DM values in liquid manure were twice as much as in urine. P concentration was higher in urine than in liquid manure. $NH_4$-N and Na in slurry, $NH_4$-N in urine and $NH_4$-N, P and Ca in fermented liquid manure were highly correlated with EC, while $NH_4$-N, P, Ca and Mg in slurry, $NH_4$-N and Ca in urine, and K, P, Ca, Mg, and Na in fermented liquid manure with DM (P<0.05). BOO in slurry (22,520 mg/mL) was higher than that in urine (4,763) and fermented liquid manure (2,701). Results indicated that slurry is a better fertilizer source than urine or fermented liquid manure. However, slurry may pollute soil more than urine or fermented liquid manure when applied to land, although the levels are not above the permit.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.94-101
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• 2005

The present study was conducted to know the physicochemical properties of Korean tea according to degree of fermention. The moisture content of green tea, blue tea, yellow tea and black tea was 2.02∼2.04%. The content of total nitrogen was 3.78 % in green tea and 3.49∼4.03% in fermented tea. The content of the mineral was highest in Ca, Mg. The content of vitamin C was 670.62 mg in green tea and 169.7∼85.03 mg in fermented tea. The content of vitamin C were increased as tea was more fermented. The composition of vitamin E and β-carotene was green tea> blue tea> yellow tea> black tea. The content of the rutin was 0.12 % in green tea and 1.37% in black tea. The content of rutin was increased with fermentation. The content of total amino acid of green tea was 2270.9 mg. The content of main amino acid of Glu, Asp, and Leu was 342.01 mg, 165.32 mg, and 161.69 mg and the hightst content of Glu. The content of total amino acid of black tea was 2,219.08 mg. Total amino acid content of fermented tea increased in the order of black tea> blue tea> yellow tea, and among the tea, the content of black tea was the highest in the fermented tea. The content of caffeine was 1.17% in green tea and 1.05∼1.32% fermented tea. These results were nothing in the content of caffeine during the fermentation. The content of theanine was 0.95% in green tea and 0.73∼1.42% in fermented tea. The content of total catechin was highest in green tea, and decreased sharply as tea was more fermented. Flavonoid content of 1.05% in green tea. DPPH radical scavenge activities of the teas 4.73∼19.5% mg.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.476-476
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• 2014

서론: 저 전력 소모를 필요로 하는 무선 센서 네트워크 관련 기술의 급격한 발달과 함께 자체 전력 수급을 위한 진동 에너지 수확 기술에 대한 연구가 활발히 이루어지고 있다. 다양한 구조와 소재를 압전 외팔보에 적용하여 제안하고 있다. 그 중에서도 진동 기반의 에너지 수확 소자는 주변 환경에서 쉽게 진동을 얻을 수 있고, 높은 에너지 밀도와 제작 방법이 간단하다는 장점을 가지고 있어 많은 분야에 응용 및 적용 가능하다. 기존 연구에서는 2차원적으로 진동 에너지 수확을 위한 휜 구조의 압전 외팔보를 제안 하였다. 휜 구조를 갖는 압전 외팔보는 각각의 짧은 두 개의 평평한 외팔보가 일렬로 연결된 것으로 볼 수 있다. 하나의 짧고 평평한 외팔보는 진동이 가해지면 접선 방향으로 응력이 생겨 최대 휨 모멘텀을 갖게 된다. 그러므로 휜 구조를 갖는 외팔보는 진동이 인가됨에 따라 길이 방향과 수직 방향으로 진동한다. 하지만, 이 구조는 수평 방향으로 가해지는 진동에 대한 에너지를 수확하기에는 한계점을 가진다. 즉, 3축 방향에서 임의의 방향에서 진동 에너지를 수확하기는 어렵다. 본 연구에서는 3축 방향에서 에너지를 효율적으로 수확할 수 있도록 헤어-셀 구조의 압전 외팔보 에너지 수확소자를 제안한다. 제안된 소자는 길이 방향과 수직 방향뿐만 아니라 수평 방향으로도 진동하여 임의의 방향에서 진동 에너지를 수확할 수 있다. 구성 및 공정: 제안하는 소자는 3축 방향에서 임의의 진동을 수확하기 위해서 길이를 길게 늘이고 길이 방향을 따라 휘어지는 구조의 헤어-셀 구조로 제작하였다. 외팔보의 구조는 외팔보의 폭 대비 길이의 비가 충분히 클 때, 추가적인 자유도를 얻을 수 있다. 그러므로 헤어-셀 구조의 에너지 수확 소자는 기본적인 길이 방향, 수직방향 그리고 수평방향에 더불어 추가적으로 뒤틀리는 방향을 통해서 3차원적으로 임의의 주변 진동 에너지를 수확하여 전기적인 에너지로 생성시킬 수 있다. 제작된 소자는 높은 종횡비를 갖는 무게 추($500{\times}15{\times}22{\mu}m3$)와 길이 방향으로 길게 휜 압전 외팔보($1000{\times}15{\times}1.7{\mu}m3$)로 구성되어있다. 공정 과정은 다음과 같다. 먼저, 실리콘 웨이퍼 위에 탄성층을 형성하기 위해 LPCVD SiNx를 $0.8{\mu}m$와 LTO $0.2{\mu}m$를 증착 후, 각각 $0.03{\mu}m$과 $0.12{\mu}m$의 두께를 갖는 Ti와 Pt을 하부 전극으로 스퍼터링한다. 그리고 Pb(Zr0.52Ti0.48)O3 박막을 $0.35{\mu}m$ 두께로 졸겔법을 이용하여 증착하고 상부 Pt층을 두께 $0.1{\mu}m$로 순차적으로 스퍼터링하여 형성한다. 상/하부 전극은 ICP(Inductively Coupled Plasma)를 이용해 건식 식각으로 패턴을 형성한다. PZT 층과 무게 추 사이의 보호막을 씌우기 위해 $0.2{\mu}m$의 Si3N4 박막이 PECVD 공정법으로 증착되고, RIE로 패턴을 형성된다. Ti/Au ($0.03/0.35{\mu}m$)이 E-beam으로 증착되고 lift-off를 통해서 패턴을 형성함으로써 전극 본딩을 위한 패드를 만든다. 초반에 형성한 실리콘 웨이퍼 위의 SiNx/LTO 층은 RIE로 외팔보 구조를 형성한다. 이후에 진행될 도금 공정을 위해서 희생층으로는 감광액이 사용되고, 씨드층으로는 Ti/Cu ($0.03/0.15{\mu}m$) 박막이 스퍼터링 된다. 도금 형성층을 위해 감광액을 패턴화하고, Ni0.8Fe0.2 ($22{\mu}m$)층으로 도금함으로써 외팔보 끝에 무게 추를 만든다. 마지막으로, 압전 외팔보 소자는 XeF2 식각법을 통해 제작된다. 제작된 소자는 소자의 여러 층 사이의 고유한 응력 차에 의해 휨 변형이 생긴다. 실험 방법 및 측정 결과: 제작된 소자의 성능을 확인하기 위하여 일정한 가속도 50 m/s2로 3축 방향에 따라 입력 주파수를 변화시키면서 출력 전압을 측정하였다. 먼저, 소자의 기본적인 공진 주파수를 얻기 위하여 수직 방향으로 진동을 인가하여 주파수를 변화시켰다. 그 때에 공진 주파수는 116 Hz를 가지며, 최대 출력 전압은 15 mV로 측정되었다. 3축 방향에서 진동 에너지 수확이 가능하다는 것을 확인하기 위하여 제작된 소자를 길이 방향과 수평 방향으로 가진기에 장착한 후, 기본 공진 주파수에서의 출력 전압을 측정하였다. 진동이 길이방향으로 가해졌을 때에는 33 mV, 수평방향으로 진동이 인가되는 경우에는 10 mV의 최대 출력 전압을 갖는다. 제안하는 소자가 수 mV의 적은 전압은 출력해내더라도 소자는 진동이 인가되는 각도에 영향 받지 않고, 3축 방향에서 진동 에너지를 수확하여 전기에너지로 얻을 수 있다. 결론: 제안된 소자는 3축 방향에서 진동 에너지를 수확할 수 있는 에너지 수확 소자를 제안하였다. 외팔보의 구조를 헤어-셀 구조로 길고 휘어지게 제작함으로써 기본적인 길이 방향, 수직방향 그리고 수평방향에 더불어 추가적으로 뒤틀리는 방향에서 출력 전압을 얻을 수 있다. 미소 전력원으로 실용적인 사용을 위해서 무게추가 더 무거워지고, PZT 박막이 더 두꺼워진다면 소자의 성능이 향상되어 높은 출력 전압을 얻을 수 있을 것이라 기대한다.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.133-147
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• 2004

Environmental quality(water and sediment) was analyzed in the tidal flat of Saemangum of Jeonbuk Province, the west coast of Korea, using the 101 sediment samples and 69 water samples collected in September 4~13, 2001. Major water quality parameters with the means of 69 surface water samples are as follows; $25.51{\pm}0.68^{\circ}C$ for water temperature, $29.88{\pm}5.01$ for salinity, $1.40{\pm}0.78mg/L$ for COD, $0.352{\pm}0.417mg/L$ for DIN, and $0.027{\pm}0.023mg/L$ for phosphate, respectively. Higher values were found at the subestuary of Dongjin and Mangyung River, and lower values at the Saemangum embayment and Gomso Bay. There was a significant negative correlation between salinity and the other water quality parameters(p<0.0001) such as COD, nutrients, SS and N/P. This correlation suggested that the major pollution sources be from terrestrial inputs through tributaries in this area. Principal component analysis clearly revealed a spatial variation of water quality; stations with higher values of nutrients and COD located subestuary of tributaries. 14 sediment quality parameters including 8 trace metals were measured using the 101 surface sediment samples. Average values for the parameters are as follows; Al $2.28{\pm}0.92%$, Cd $0.61{\pm}0.27ppm$, Cu $8.95{\pm}4.06ppm$, Fe $1.19{\pm}0.37%$, Mn $182.31{\pm}77.45ppm$, Ni $10.83{\pm}4.97ppm$, Pb $15.20{\pm}4.35ppm$, Zn $41.34{\pm}34.62ppm$, COD $2.68{\pm}1.85mg/g\;dry$, AVS $0.04{\pm}0.08mg/g\;dry$, IL $1.29{\pm}1.08%$, water content $24.11{\pm}4.49%$, TN $0.02{\pm}0.02%$, TC $0.22{\pm}0.30%$. Spatial variations of sediment quality were not clear as water quality. Some higher values were found at the subestuary of Gum River and lower values at the other area. There was a significant positive correlation between the heavy metal concentrations and organic materials within the sediment(p<0.05). Enrichment factors showed the ranges of 1~2 for most of the metals in the sediment except zinc(1~6), indicating no serious exogenous input of heavy metals in the study area. Also, the heavy metal concentrations in the sediment were within the ranges found at the natural marine environments.

• Economic and Environmental Geology
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• v.42 no.2
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• pp.121-131
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• 2009

The distribution characteristics of heavy metals for surface sediments in east oceanic dumping area (EDA) and west oceanic dumping area (WDA) are evaluated by grain sizes, minerals, sedimentation rates and compositions of heavy metals. The mean grain sizes in EDA and WDA range from $7.95{\Phi}$ to $8.51{\Phi}$ and $7.42{\Phi}$ to $8.15{\Phi}$, respectively. These are mostly belonging to the M (mud) type. Minerals in the surface sediments consist of illite with chlorite, smectite, and kaolinite. Sedimentation rates estimated by $^{210}Pb$ method in EDA and WDA are 1.11 mm/yr$\sim$1.73 mm/yr and 1.87 mm/yr, respectively. According to the interrelationship, concentrations of Ni, Cu, Cr, and Zn are closely associated with mean grain size, Al, and Fe, whereas concentrations of Cd and Pb are poorly associated with ones. The enrichment factors of these elements are higher than 1.5, suggesting that the concentrations of Cd and Pb in the surface sediments are affected by anthropogenic sources. The $I_{geo}$-class numbers of Cd and Pb in the surface sediments are mostly classified in 2 to 4, showing moderate to strongly polluted. These numbers in EDA are higher than that of WDA, and the highest number is 4, indicative of the strongly polluted class. Our results show that the disposed wastes at EDA include mineralogical wastes, dredged materials from sewage disposals, and sludges from constructions having materials of WDA. The annual amount of oceanic dumping in EDA is double than that in WDA.

• Economic and Environmental Geology
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• v.22 no.1
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• pp.35-63
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• 1989

Geochemical characteristics of the Guryongsan (Ogcheon) uraniferous black slate show that this is an analogue to the conventional Chattanooga and Alum shales in occurrences. Whereas, its highest enrichment ratio in metals including uranium, among others, is explained by the cyclic sedimentation of the black muds and quartz-rich silts, and the uniform depositional condition with some what higher pH condition compared to the conditions of the known occurrences. The cyclic sedimentation, caused by the periodic open and close of the silled basin, has brought about the flush-out) of the uranium depleted water and the recharge with the new metal-rich sea water, which consequently contributed to the high concentration of metals in mud. The metal-rich marine black muds, which mostly occur in the early to middle Palaeozoic times, is attributed by the geologic conditions which related to the atmospheric oxygen contents, and these are scarcely met in the late Precambrian and/or with the onset of Palaeozoic era in the geologic evolution of the earth.