• Journal of the korean society of oceanography
• /
• 제36권3호
• /
• pp.59-71
• /
• 2001

In order to investigate the temporal variability of dissolved and particulate trace metals in the Han River, water samples were collected intermittently at two sites for 3 years (August 91 to December 94). Surface seawaters covering the range of salinity were also collected at the estuarine region to evaluate the role of estuary for the riverine fluxes of trace metals within the estuary during October 95 and 96. During the study period, dissolved metal concentrations in riverwaters varied by a factor of 5-10 for Fe, Ni, Co and Cu and 50-100 for Mn, Cd and Pb depending upon the water level; high concentration during the low water and low concentration in high water period except for Fe. The concentration of dissolved Fe increased with increasing water discharge. These concentration-discharge relationships of the studied trace metals are explained by the successive dilution of waters from two different origins, which can be presumably identified as anthropogenic discharges and watershed flushing. Although estuarine waters at early mixing region were not collected due to the difficulty of sampling, mixing behaviors of metals were inferred from the concentration-salinity relationships through the laboratory mixing experiment and field sampling, and distribution coefficients between dissolved and labile particulate phases. It is suggested that the Han River estuary plays a role of accumulating Fe, Mn, Co and Pb from riverine sources due to high turbidity caused by strong tidal current, whereas this system serves as a source of dissolved Cd due to release caused by extended residence time of riverine particles.

• Journal of Microbiology
• /
• 제45권1호
• /
• pp.48-52
• /
• 2007

A new procedure for the concentration of nonoviruses from water samples has been developed. This procedure (calcium flocculation-citrate dissolution method) uses the following steps: virus flocculation formed by treatment with 1 M $CaCl_2$ and 1 M $Na_2HPO_4$, virus release by sodium citrate dissolution (0.3 M Na citrate, pH 3.5), and virus re-concentration by ultrafiltration. When reverse transcription (RT)-PCR was performed after the procedure, the overall detection sensitivity for seeded noroviruses in a one liter drinking water sample was as low as 1 RT-PCR unit, which is equal to a $10^{-6}$ dilution of the virus sample. This approach showed at least a 5-fold-higher sensitivity than the current method with its three steps of adsorption-elution-concentration. The newly developed procedure was used to test different brands of bottled drinking water from China for putative contamination with noroviruses. A total of 144 samples were analyzed; all of the samples were negative for norovirus specific nucleic acids.

• 한국식품영양과학회지
• /
• 제46권7호
• /
• pp.816-821
• /
• 2017

제주 water를 농축하여 새싹유채, 메밀, 보리의 종자발아 영향과 생장 및 vanadium 흡수특성을 알아보고자 실험을 수행하였다. 제주 water를 배수별로 농축시킨 결과 vanadium 농도가 제주 water 원수, 10배, 20배, 40배 농축수에서 각각 0.05 mg/L, 0.46 mg/L, 0.80 mg/L, 1.34 mg/L의 함량을 보였다. Control(수도수)과 제주 water 원수, 10배, 20배, 40배 농축수를 사용하여 종자발아율 측정 시 새싹유채의 경우 control과 제주 water 원수, 10배 농축수까지 발아율은 차이를 보이지 않았으나 농축배수가 20배, 40배로 증가할수록 발아율이 감소하는 경향을 보였으며, 특히 40배 농축수에서 발아율이 control과 비교하여 약 50% 감소하였다. 새싹메밀의 경우 농축배수가 증가할수록 종자 발아율이 control 42.7%에서 40배 농축수 60.7%로 발아율이 증가하는 것이 확인되었다. 새싹보리의 경우 control의 발아율 88.8%와 40배 농축수로 처리한 발아율 79.0%를 비교 시소폭 감소한 결과를 보이며, 20배 농축수까지 큰 영향은 없는 것으로 확인되었다. 새싹채소 생장 영향을 알아보고자 control(수도수), 제주 water 원수(0.05 mg/L), 제주 water 10배 농축수(0.46 mg/L)로 7일간 재배하여 확인한 결과 새싹유채의 경우 vanadium 농도가 높아질수록 지상부 길이, 뿌리의 생장이 모두 억제되었으며, 생물 중량 및 건조물 중량 또한 control과 비교 시 10배 농축수로 재배한 조건에서 감소하였다. 새싹메밀의 경우 vanadium 농도가 증가함에 따라 지상부 길이의 생장이 증가하였지만, 지하부 뿌리의 생장은 역으로 생장이 억제되었고, 생물 중량 및 건조물 중량 또한 새싹유채와 동일하게 vanadium 농도가 증가할수록 감소하였다. 새싹보리의 경우 새싹메밀과 동일한 경향으로 제주 water 원수 처리 시 control과 비교하여 지상부 생장이 억제되었지만 10배 농축수 처리 시 지상부의 생장이 증가하였고 뿌리생장은 억제되었으며, 생물 중량 및 건조물 중량은 control 대비 10배 농축수에서 감소하였다. 또한, 새싹채소의 vanadium 흡수특성을 확인한 결과 공통적으로 새싹유채, 새싹메밀, 새싹보리 control에서 vanadium 함량은 검출한계 이하의 함량을 보였다. 새싹유채의 경우 제주 water 원수와 제주 water 10배 농축수에서 각각 1.4 mg/kg과 4.2 mg/kg으로 함량이 3배 정도 차이를 보이는 것을 확인할 수 있었고, 새싹메밀의 경우 제주 water 원수와 10배 농축수로 재배한 경우 vanadium의 함량이 각각 1.3 mg/kg, 2.9 mg/kg으로 새싹유채보다 낮은 함량을 갖는 것으로 확인되었다. 새싹보리의 경우 vanadium 함량은 본 연구에서 제주 water 원수, 10배 농축수 재배조건 모두 검출한계 이하의 함량을 보였다.

• 대한한방내과학회지
• /
• 제11권2호
• /
• pp.94-103
• /
• 1990

To evaluate effects of Ga Gam Sam Kee Tang(GGSKT) water extract on the plasma cortisol concentration and arterial blood $PCO_2,\;PO_2$ in the rabbit. The results obtained were as follows : 1. Intravenous administration of GGSKT water at the dose of $0.2m{\ell}/kg$ remarkably increased plasma cortisol concentration from 1 to 2 hours. 2. Oral administration of GGSKT water extract at the dose of $10m{\ell}/kg$ significantly decreased plasma cortisol concentration on 3 hours. 3. Intravenous administration of GGSKT water extract at the dose of $0.4m{\ell}/kg$ remarkably decreased arterial blood $PO_2$ on 2 hours. 4. Oral administration of GGSKT water extract at the dose of $1.0m{\ell}/kg$ significantly decreased arterial blood $PO_ 2$ on 2 hours and remarkably increased on 4 hours. 5. Intravenous administration of GGSKT water extract at the dose of $0.2m{\ell}/kg$ remarkably increased arterial blood $PCO_2$ on 4 hours. 6. Oral administration of GGSKT water extract at the dose of $2.0m{\ell}/kg$ significantly decreased arterial blood $PCO_2$ from 1 to 2 hours. These results suggest that therapeutic action of GGSKT water extract for athma may be related with the increment of plasma cortisol concentration and the decrease of arterial blood $PCO_2$.

• 현장농수산연구지
• /
• 제21권1호
• /
• pp.115-122
• /
• 2019

상추 양액 재배 시 탄산수 엽면시비는 탄산수의 이산화탄소 농도가 높을수록 광합성률, 기공전도도가 높았으며, 내서성이 향상되었다. 상추 생육은 탄산수의 이산화탄소 농도가 높을수록 좋았으나, 이산화탄소 농도가 700 ppm, 500 ppm 에서는 tip-burn 발생률이 높아 수량은 300 ppm, 대조구가 700 ppm, 500 ppm 보다 많았다. 본 연구 조건하에서 탄산수 엽면시비에 의한 고온 한계 시점을 분석하기 위하여 기온 처리별 F_O를 조사한 결과 무처리구에는 32℃, 300 ppm은 33℃, 500 ppm은 34℃, 700 ppm은 36℃이었다. 이 결과를 보면 탄산수 엽면시비는 작물의 고온 한계 온도를 최고 약 4 ℃정도 높이므로 내서성이 향상된 것으로 판단되었다. 또한 탄산수의 이산화탄소 농도가 높을수록 항산효소 SOD(superoxide dismutase) 활성이 높았다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2002년도 학술발표회 발표논문집
• /
• pp.473-476
• /
• 2002

The effect of fertiltzer application on ponded and percolation water in rice paddy were investigated at the experimental plots during irrigation period. We laid out three experimental plots such as 150% Excessive, 100% Standard and 70% Reduced. The concentration of T-N and T-P in ponded water were increased rapidly after application. The concentration of T-N and COD in percolated water increased with fertilizer application rates, while T-P concentration were almost constant.

• 한국식품과학회지
• /
• 제22권5호
• /
• pp.497-502
• /
• 1990

삼투압 농축중 설탕용액의 농도와 온도 및 침지시간에 따른 감자 내부의 수분손실, 고형분 증가나 손실 및 몰랄농도를 반응 표면 분석법으로 조사하였고, 이차 다항 회귀 모델로써 예측하였다. 또한 삼투압 농축과 데치기가 6%수분(wet basis)까지 열풍조건시 비타민 C 함량유지에 미치는 효과를 평가하였다. 감자내부의 수분손실, 고형분 증가나 손실, 몰랄농도, 속도 매개변수 및 비타민 C 함량에 가장 크게 영향을 미치는 요소는 설탕농도이었고 그 다음 침지시간과 침지온도 순이었다. 수분손실과 설탕흡수는 초기 10분간 침지과정에서 빠르게 이루어진 후 증가현상이 둔화되었다. 설탕용액 $(60\;Brix,\;80^{\circ}C)$에서 20분간 침지 후 44.6%의 수분손실이 되었다. 삼투압 농축후 건조시킨 감자가 데치기 한 후 건조시킨 감자보다 높은 비타민 C 함량을 유지하였다. 30% 이상의 수분손실과 50% 이상의 비타민 C 함량유지의 관점에서 삼투압농축공정의 최적조건은 $60-70^{\circ}C$의 침지온도와 60 Brix의 설탕농도 및 16-20분간의 침지시간이었다.

• 한국환경과학회지
• /
• 제13권7호
• /
• pp.627-635
• /
• 2004

Evaluated were household THMs exposure associated with the use of municipal tap water treated with chlorine and with ozone-chlorine. The current study measured the THMs concentrations in the tap water and indoor and outdoor air in the two types of household, along with an estimation of THMs exposure from water ingestion, showering, and the inhalation of indoor air. Chloroform was the most abundant THMs in all three media, yet no bromoform was detected in any sample. Contrary to previous findings, the fall water THMs concentrations exhibited no significant difference between the chlorine and ozone-chlorine treated water. However, the spring median chloroform concentration in the tap water treated with chlorine (17.6 ppb) was 1.3 times higher than that in the tap water treated with ozone-chlorine (13.4 ppb). It is suggested that the effects of the water parameters should be considered when evaluating the advantage of ozone-chlorine disinfection for THMs formation over chlorine disinfection. The indoor air THMs concentration trend was also consistent with the water concentration trend, yet the outdoor air THMs concentrations did not differ significantly between the two types of household. The indoor to outdoor air concentration ratios were comparable with previous studies. The THMs exposure estimates from water ingestion, showering, and the inhalation of indoor air suggested that, for the residents living in the surveyed households, their exposure to THMs in the home was mostly associated with their household water use, rather than the indoor air. The THMs exposure estimates from tap water ingestion were similar to those from showering.

• 한국환경보건학회지
• /
• 제19권2호
• /
• pp.1-9
• /
• 1993

In public water supply systems, Alum and/or PAC being used as a coagulant. It is well known that their use increased frequently the concentration of residual aluminum in filtered water upon operating conditions. This study was conducted to find the optimum conditions that both the concentration of residual aluminum and turbidity are minimized by changing such factors as pH, temperature, alum dosage, mixing rate, alkalinity and hardness. The results can be summarized as follows: The pH values for the minimum concentration of residual aluminum and turbidity as a given experimental condition were found at pH 6 and pH 7 respectively, the apparent clarity was best at pH 8. The floc settling rate was the greatest at pH 6.5, but the turbidity was high at the same condition. The more alum dosage, the higher the concentration of residual aluminum. However the alum dosage less than 15 mg/l tend to decrease in turbidity. Restabilization and enmeshment occurred near 15 mg/l and 20 mg/l of alum dose respectively. With the increase of mixing rate (rapid and slow), the concentration of residual aluminum and turbidity are increased and the same trend was found in increment of mixing time. At low water temperature, the concentration of residual aluminum was decreased, but turbidity was increased. It was confirmed that alkalinity had an effect on the coagulation efficiency, but hardness did not.

• 한국식생활문화학회지
• /
• 제16권4호
• /
• pp.388-397
• /
• 2001

Wild edible plants are consumed as raw and/or processed. Analytical data for raw biologically functional compounds were relatively well established. The changes on functional compounds during processing are, however, not well studied. This study was carried out to investigate the change of the quality of wild edible plants, Pimpinella brachycarpa(Chamnamul) at various conditions. Samples were blanched at the salt concentration of 0%, 1% or 2% for 1, 2, and 3 minutes each. The biologically active compounds, vitamin C, ${\beta}-carotene$, chlorophyll, flavonoids, polyphenols and minerals were analyzed. The concentration of vitamin C in Chamnamul decreased as blanching time increased. Beta-carotene in Chamnamul showed high concentration when Chamnamul was treated under longer blanching time. Higher salt concentration of blanching water, however, resulted in the increased concentration of ${\beta}-carotene$ in the blanched Chamnamul. Higher salt concentration of blanching water also reduced the loss of total flavonoids and total polyphenols from the blanched Chamnamul. The change of colors in the blanching water seemed to be corresponding to those of total flavonoids and total polyphenols concentrations in the blanching water.