• The Korean Journal of Ecology
• /
• 제16권2호
• /
• pp.169-180
• /
• 1993

Soils of four combinations, sand with high content of organic matter(SL), sand with low content of OM(SS), siltyl loam with high content of OM(LL) and silty loam with low content OM (LS), were filled on column and then percolated with simulated sulfuric acid rain with pH 5.6, 4.0, 3.5, 3.0 and 2.5. From soil leachates, pH and concentrations of basic cations and Al were determined. Cation concentrations in the leachates increased as pH of the rain decreased. The orders of buffering capacity of soil, leachability of cation from soil, leaching sensitivity of ion andbase saturation sensitivity of soil to acidity of the rain water were SS$\leq$K <$\leq$LL

• 한국토양비료학회지
• /
• 제18권3호
• /
• pp.240-246
• /
• 1985

사질답(砂質畓)의 토양개량제(土壤改良劑)로서 사용(使用)할 Zeolite의 최적(最適) 입도(粒度)를 알아보기 위한 기초실험으로서 입경(粒徑)이 다른 모래의 column에 입경별(粒徑別) Zeolite를 시용(施用)하여 Zeolite 이동(移動)을 조사(調査)한 결과(結果)는 다음과 같다. 0.1mm이상(以上) 크기의 Zeolite입자(粒子)는 96시간(時間) 투수(透水)하여도 수직이동(垂直移動)은 거의 없었다. 0.1mm이하(以下) 크기의 Zeolite입자(粒子)는 96시간(時間) 투수(透水)함으로 2~1, 1~0.5, 0.5~0.25mm sand column에서 각각 85.7, 32.64, 25.50% 이동(移動)하였다. 공극크기 측면만을 고려한 대하천 주위의 사질답(砂質畓)에 적합한 Zeolite입자(粒子)는 0.25~0.1mm fraction으로 추정되었다.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2005년도 학술발표회 논문집
• /
• pp.1254-1258
• /
• 2005

Net outflow flux and unit load of pollutants were investigated at a paddy fields area(Soro-ri) with large-scaled plots on loam soil during irrigation seasons of $2001\~2003$. Water samples were collected, and inflow and outflow were .measured at $5\~10$ day intervals during non-storm periods and at $2\~6$ hours intervals during storm events. The average concentration of TP in percolated water was much smaller than that in irrigation and surface outflow water likely due to phosphorus absorption capacity of paddy soils. Net outflow flux in study area was significantly correlated with rainfall and surface outflow discharge. Nutrient flux from Paddy fields can be abated by reduction in outflow surface discharge.

• 한국농공학회지
• /
• 제43권6호
• /
• pp.163-173
• /
• 2001

This study describes the characteristics of concentrations of pollutants such as total nitrogen(T-N), total phosphorous(T-P), and chemical oxygen demand(COD) at paddy areas during 2-year irrigation periods. The most common order in average concentrations of T-P and COD is podded water > irrigation(or drainage) water > percolated water. Most of pollutants concentrations in drainage water are lower than those in irrigation water after early July due to large uptake of pollutants by rice crop and denitrification. The exponential L (load)-Q(discharge) equations for classified irrigation periods are significant at 0.001 level for irrigation and drainage waters. For drainage water, the concentrations of T-N and COD slightly decrease with discharge, while the T-P concentrations slightly increase with discharge.

• 산업기술연구
• /
• 제33권A호
• /
• pp.67-72
• /
• 2013

CNT(carbon nanotube) humidity sensors with plasma treated electrodes exhibit a much faster response time and a higher sensitivity to humidity, compared to untreated CNT and porous Cr electrodes. These results may be partially due to their percolated pore structure being more accessible for water molecules and for expending the diffusion of moisture to the polyimide sensing film, and partially due to the oxygenated surface of CNT films. This paper shows a plasma process effect and selectivity characteristics of CNT film humidity sensor.

• 한국토양비료학회지
• /
• 제21권4호
• /
• pp.409-415
• /
• 1988

보릿짚시용(施用)이 수도재배(水稻栽培) 논 토양성분(土壤成分)의 용탈(溶脫)에 미치는 영향을 규명하기 위(爲)하여 투수(透水)를 실시하고 투수액(透水液) 및 토양성분(士壤成分)을 분석검토(分析檢討)한 결과(結果)는 다음과 같다. 침투수중(浸透水中) $NO_3-N$는 초기(初期)부터, 토양중(土壤中)의 $NH_4-N$ 와 $NO_3-N$은 분얼최성기부터 검출(檢出)되지 않았으며 토양중(土壤中)에서는 보릿짚시용구(施用區)가 약간 높았다. 인산(燐酸)에 대한 보릿짚시용(施用)의 영향은 없었으나 경시적으로 소량씩 용탈(溶脫)되었다. 석회(石灰)와 고토(苦土)의 용탈(溶脫)양상은 유사한 경향을 나타냈으며 가리(加里), 나트륨 및 염소(鹽素)의 경시적변화(經時的變化)도 비슷하였지만 보릿짚시용구(施用區)의 용탈(溶脫)이 전반적으로 컸다. 황산(黃酸)이온의 용탈(溶脫)은 시용구(施用區)가 분얼기에는 낮았으나 출수기 이후에는 높았으며 전용탈량(全溶脫量)은 분얼기에 많았다. 철(鐵)의 용탈(溶脫)도 분얼기 보릿짚시용구(施用區)에서 급격히 증대(增大)된 후(後) 출수기부터는 시용유무(施用有無)에 관계없이 소량만이 용탈(溶脫)되었으며, 토양중(土壤中)의 2가철(價鐵)은 보릿짚시용재배구(施用栽培區)가 높았으며 경시적(經時的)으로 증가(增加)하였다. 재배후(栽培後) 토양중(土壤中)의 잔존부식형태(殘存腐植形態)는 보릿짚 시용유무(施用有無)에 관계(關係)없이 부식화(腐植化)가 약간 진행된 B형(型)으로 동일(同一)하였으며 부식산량(腐植酸量)은 60% 정도(程度)였다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2002년도 학술발표회 발표논문집
• /
• pp.445-448
• /
• 2002

In this study, we investigated concentrations and loads of nutrients in the paddy plots with conventional and environmental farming method. For two experimental plot, type of fertilizer for basal dressing was different but total applied fertilizer rates was almost identical. The nutrient concentrations in irrigation and percolated water were almost constant, while the ponded water significantly increased after fertilizer application. The nutrient concentrations in ponded water at long distance from inlet was higher than those at short distance due to longer detention time.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2001년도 학술발표회 발표논문집
• /
• pp.466-469
• /
• 2001

The effect of fertiltzer application on ponded and percolation water in paddies were evaluated 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.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2000년도 학술발표회 발표논문집
• /
• pp.605-610
• /
• 2000

The effect of slow release fertilizer application on ponded and percolation water in paddies were evaluated at the experimental plots during irrigation period. We laid out three experimental plots such as standard, 100% slow-release and 80% slow-release. For ponded water, the concentrations of T-N in slow-release plots slowly increase after fertilizing and decrease slowly. The concentration of COD in percolated water was independent of the type of plots. Amount of nitrogen uptake of rice plant in a standard plot was highest at the middle or end of July and was higher than the other plots.

• 한국환경농학회지
• /
• 제19권3호
• /
• pp.218-222
• /
• 2000

중석광의 광미를 매립한 토양에서 유출되는 침출수에 의한 환경영향을 알아보기 의하여 시기별로 용출수를 분석하고 및 zeolite column실험을 통하여 용출수 중의 zeolite를 이용하여 중금속 제거 가능성을 조사하였다. 폐재댐 침출수는 As $1.21{\sim}1.54ppm$, Pb $0.11{\sim}0.15ppm$, $SO_4\;^{2-}\;302{\sim}378ppm$으로 건설된지 수년이 지난 지금까지도 수질을 오염시키는 정도의 중금속이 침출되고 있다. 탈이온수 및 인공산성비 (pH3, pH4)를 광미를 충진시킨 칼럼을 통과시켰을 때 pH 4의 용액에 의하여 용출되는 Mn, Na, Ca량이 탈이온수에 의한 용출보다 $1{\sim}8%$정도 증가되었으나, W, Mo은 pH가 높을수록 용출량이 많았다. Zeolite에 의한 용출수 중 중금속 제거효과는 중금속의 종류에 따라 약간씩 다르게 나타났지만 zeolite를 통과한 용액에서 낮은 농도의 중금속이 검출 되어, zeolite에 의한 폐재댐의 중금속 제거가 효과가 높은 것으로 판단되었다.