• 산업기술연구
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• 제18권
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• pp.1-6
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• 1998

This study was conducted to use disused vinyl as biofilm for biological sewage treatment. Efficiency verification was performed on laboratory and on-site plant. In laboratory study, total biochemical oxygen demand(TBOD) removal rate was ranged 94.8~97 % in each hydraulic retention tim(HRT), 12, 16, 20, 24 hr, respectively. At that time, filling rate was 50 %. And effluent TBOD concentration was low ranged 3.64~6.28 mg/L. In on-site plant, TBOD removal rate was ranged 88.2~96.8 % and effluent TBOD concentration was 4.8~17.7mg/L. This concentration was lower than disign effluent concentration, 30mg/L. Total kjeldhal nitrogen(TKN) removal efficiency was ranged 56.8~90.9%. This was resulted higher than Lab. scale treatment efficiency.

• 한국산림과학회지
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• 제98권5호
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• pp.558-562
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• 2009

The growth, carbon and nitrogen status of container grown black pine (Pinus thunbergii) seedlings were examined at various levels of foliar fertilization (control, 0.1%, 0.2%, 0.3%). Root collar diameter, height and dry weight of black pine seedlings increased significantly with increasing levels of foliar fertilization (P<0.05). Carbon concentration in needle of black pine seedlings was significantly higher in the foliar fertilization than in the control treatments (P<0.05), while other seedling components such as stem and roots were not significantly different (P>0.05) between the foliar fertilization and the control treatments. Nitrogen concentration and content were significantly greater in the foliar fertilization than in the control treatments (P<0.05). Shoot/root ratio of black pine seedlings (needle+stem dry weight/root dry weight) was greater in the foliar fertilization (2.40-2.89) than in the control treatments (1.87). However, nitrogen use efficiency was significantly lower (P<0.05) in the foliar fertilization (28-46) than in the control (111) treatments. The results indicate that morphological characteristics and nutritional status on container grown black pine seedlings were enhanced by various levels of foliar fertilization.

• 한국초지조사료학회지
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• 제21권2호
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• pp.59-66
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• 2001

In order to determine the influence of nitrogen on agronomic characters, forage yield and quality, a Kenaf was cultured on the volcanic ash soil at the Experimental Farm of Cheju national University under the seven levels of nitrogen rates(0, 50, 100, 150, 200, 250kg/ha) from April 25 to Dec. 25, 1999. The plant height increased by increase of nitrogen rate, showing longest 250kg/ha with 286.6cm and shortest at no application plot with 255.7cm. The difference on leaf number, leaf withering number, stem diameter and branches number by nitrogen rate showed a similar tendency to the plant height. Increasing N rate from 0 to 250kg/ha fresh forage yield form 55.8 to 99.8MT/ha, dry matter (DM) yield from 8.8 to 15.8MT/ha, crude protein(CP) yield form 1.2 to 3.1MT/ha, total digestible nutrients (TDN) yield from 3.8 to 8.6MT/ha. However, no significant differences in these yields were found between 200 and 250kg N/ha. Nitrogen uptake increased form 192.9 to 496.2 kg/ha but N use efficiency decreased form 95.0 to 66.6 kg DM$^{a}$ /kg N with increasing from 0 to 250 kg/ha. As N rate increased from 0 to 250kg/ha, leaf and stem out of CP, crude fat (CF), nitrogen free extract (NFE), TDN contents increased from 20.1% to 25.8% and from 9.7% to 12.4%, from 5.6% to 8.1% and from 3.3% to 4.4%, from 36.1% to 40.2% and from 21.9% to 32.4%, from 59.3% to 75.0% and from 32.2% to 38.2%, respectively, while leaf and stem out of crude fiber decreased from 18.5% to 16.7% and from 51.5% to 39.3%. Based on the these findings, the optimum N rate for forage production of kenaf seems to be about 200 kg/ha in atmospheric phenomena and volcanic ash soils of jeju island.

• 한국건설순환자원학회논문집
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• 제11권4호
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• pp.493-500
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• 2023

본 연구에서는 전도성 재료를 혼입한 광촉매 보도블록을 제조하여 질소산화물 제거율에 미치는 영향을 살펴보고 내구성이 향상된 블록을 제조하고자 하였다. 광촉매와 전도성 재료인 활성탄소를 혼입시 광촉매 효율이 향상되었으며 전도성 광촉매 콘크리트 블록의 경우 광촉매 콘크리트 블록보다 질소산화물 제거율이 2.5배 정도 향상되었다. 전도성 광촉매 시험편의 질소산화물 제거율이 높게 나타난 것은 전도성 재료인 활성탄소의 영향으로 TiO₂ 광분해로 인한 광전류가 많이 발생한 영향으로 볼 수 있으며 광촉매 시험편과 전도성 광촉매 시험편의 질소산화물 제거율 실험결과와 광전류 시험결과를 비교 분석하였다.

• 한국대기환경학회지
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• 제26권3호
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• pp.330-338
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• 2010

In this study, removal characteristics of nitrogen oxides $(NO_x)$ from road transport by using peat as the packing media for biodegradation have been investigated in the long term. Physicochemical and biological treatment of peatmixed media eliminates any requirement to use chemical substances and also facilitates the biodegradable actions of microorganism. Safe biodegradation of pollutants, no need to apply additional microbes owing to their active growth, and no generation of secondary pollutants were found in this experiment. It was concluded that average removal efficiencies of nitric oxide (NO) and nitrogen dioxide $(NO_2)$ were 80% and 97% respectively with respect to the linear velocity 35~40 mm/s and 0.3 ppm ozone concentration in the long period operation. Inflow concentration of nitric oxide over 0.05 ppm was suitable when pretreated with ozone. Non-ozone stage was performed with linear velocity 20~100 mm/s and then the average removal efficiency of nitric oxide and nitrogen dioxide were 38% and 94% respectively. Other results showed that the apparent static pressure was raised with increases in applied water content and aerial velocity in mixed media during fan operation.

• Asian-Australasian Journal of Animal Sciences
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• 제27권1호
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• pp.24-29
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• 2014

The objective of this study was to assess the effect of substituting corn with soybean hulls on the ingestive behavior and nitrogen balance of Santa Ines lambs. A total of 25 lambs with an initial body weight of $20{\pm}2$ kg at approximately six months of age, sheltered individually in stalls ($1.10m{\times}1.0m$), considering an entirely casual experimental delineation. Soybean hulls were substituted for corn at 0, 250, 500, 750, and 1,000 g/kg of dry matter (DM). The time spent feeding, ruminating, masticating, and resting was not affected by the substitution of corn with soybean hulls. In fact, the feeding efficiency in g DM/h and the rumination efficiency in g DM/bolus increased linearly with soybean hull substitution in the feed. Although the nitrogen balance was not altered by the use of soybean hulls as a substitute for corn in the diets of Santa Ines lambs, the N ingested and N digested expressed in g/d, N retained as a percentage of that ingested, and N retained as a percentage of that digested displayed quadratic behavior. In conclusion, corn can be substituted with soybean hulls up to 1,000 g/kg of dry matter in the concentrate, without changing the ingestive behavior and nitrogen balance.

• 한국환경농학회지
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• 제19권2호
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• pp.122-127
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• 2000

A stream purification system was applied to the upper reaches of the Masan Reservoir to improve the water quality. This system consisted of two channels which were constructed on both sides of the stream, one side packed with crushed gravels and the other with plastic filter media. The system operated under low pollutant concentrations and high hydraulic loadings during a dry season to avoid clogging of the filter media. Removal rate and efficiency of chemical oxygen demand (COD) in the channel packed with crushed gravel were $14.8g/m^3/d$ and 11.5%, and for the channel with plastic filter media, $50.1g/m^3/d$ and 13.5%, respectively. Removal efficiencies of total phosphorus (T-P) were 6.6% (gravel) and 10.0% (plastic media). These results indicated plastic filter media having relatively high specific surface areas were more efficient than crushed gravels in removing pollutants. However, due to low influent water quality during dry season, the removal efficiencies were low. The proportion of nitrate nitrogen to total nitrogen (T-N) of the inflow was high but, as the system operated under aerobic condition, nitrate nitrogen could not denitrified. Accordingly, total nitrogen was not attenuated with this system. To improve the reservoir water quality effectively, this system should be able to treat the storm runoff containing higher pollutant loadings. When the filter materials are clogged by the storm runoff instead of backwashing, it would be more efficient to replace them, Therefore, the use of natural materials which are light, easily obtaining and replaceable, and have high specific surface areas is recommended.

• 한국산림과학회지
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• 제88권2호
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• pp.266-272
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• 1999

경기도 광릉의 중부임업시험장내 31년생 리기다소나무와 낙엽송조림지를 대상으로 임분별 3개의 $20{\times}10m$ 조사구를 선정하고 각 조사구로부터 1본씩 표본목을 선정한 후 벌도하여 지상부 현존량을 측정하고 각 부위별 양분분포를 조사하였다. 조사된 임분의 지상부 현존량은 리기다소나무의 경우 170.2ton/ha, 낙엽송은 87.2ton/ha로서 리기다소나무 임분이 낙엽송 임분에 비해 높게 나타났으며, 두 임분의 현존량의 차이는 임분 밀도의 차가 원인인 것으로 나타났다. 각 부위별 현존량 분배율은 줄기>가지>수피>잎 순이었으며, 각 부위별 조직내 양분농도는 낙엽송이 리기다소나무에 비해 높았고, 두 임분 모두 잎>가지>수피>줄기 순으로 양분농도에 차이가 있었다. 양분 축적량은 리기다소나무 임분이 질소 335.9kg/ha, 칼슘 188.6kg/ha, 칼륨 121.4kg/ha, 마그네슘 93.8kg/ha, 인산 40.4kg/ha 순이었으며 낙엽송 임분은 질소 225kg/ha, 칼슘 75.7kg/ha, 칼륨 72.9kg/ha, 마그네슘 37.1kg/ha, 인산 11.5kg/ha으로 리기다소나무 임분에서 양분 축적량이 높게 나타났다. 양분에 대한 지상부 현존량의 비로 표시되는 양분이용효율중 질소이용효율은 낙엽송 임분이 리기다소나무 임분에 비해 낮게 나타났으며 이는 리기다소나무가 낙엽송에 비해 척박지에서 더 잘 견딜 수 있는 임목의 특성을 반영하고 있다.

• 한국토양비료학회지
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• 제39권6호
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• pp.334-338
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• 2006

호남평야지 논토양의 대표토양인 전북통에서 벼 담 수직파재배시 토양물리성 개선과 진단시비로 쌀 안정생산을 위한 토양관리기술을 확립하고자 관행, 진단시비, 진단시비+퇴비+규산, 진단시비(LCU 70%)+심경, 진단시비(LCU 70%)+심토파쇄, 무질소구 등 6처리를 하여 2년간(1999~2000) 시험한 결과를 요약하면 다음과 같다. 시험후 심토에서 물리성은 관행에 비하여 경도, 용적밀도, 고상이 낮아지고 공극률이 증가되었으며 그 정도는 심토파쇄>심경 순으로 양호하였다. 시험 후 토양의 화학성은 관행에 비하여 진단시비구, 완효성비료(LCU 70%) 시용 및 토양물리성 개선구에서 유기물함량, 규산함량 등이 증가하였다. 시비질소의 토양중 $NH_4-N$ 농도는 5엽기까지는 심경구에서 가장 높게 발현되었으며 관행 대비 LCU 70% 시용구에서 성숙기까지 발현량이 많았다. 시비질소의 흡수량은 관행에 비하여 진단시비(LCU 70%)+심경, 심토파쇄구에서 많았고 질소이용률도 높았다. 쌀수량은 관행($5.22Mg\;ha^{-1}$)대비 진단시비(LCU 70%)+심토파쇄구에서 8%, 진단시비(LCU 70%)+심경구에서 4% 증수되었으며, 증수요인은 $m^2$당 입수가 많고 등숙률이 높았던 것에 기인한 것으로 사료된다.

• 유기물자원화
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• 제29권2호
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• pp.15-23
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• 2021

본 연구는 질소무기화 특성을 고려하여 개발된 유기자원 시비처방 시스템의 현장적용 가능성을 평가하기 위하여, 유기 논에서 토양 무기태질소 함량과 벼(Oriza sativa L.) 생산성을 비교하였다. 표준시비량에 준하여 동일 질소량으로 자재를 처리한 2015, 2016년과 달리, 2017년은 유기자원 시비처방 시스템 적용으로 헤어리베치(HV), 호밀+유박(R+OC), 유박 기비(OC-B), 유박 분시(OC-S), 돈분퇴비(PMC), 화학비료(CHM)의 질소 투입량이 107~133 kg/ha로 상이하였다. 처리별로 유기자원 시비처방 시스템을 적용하여 벼를 재배한 결과, 정조 수량은 유박 분시(111%), 유박 기비(110), 호밀+유박(106), 헤어리베치(101), 돈분퇴비(96) 모두 화학비료(100)와 유시한 수준을 보였다. 또한, 정조 수량과 토양 내 누적 무기태질소 함량은 정의 상관관계(R²=0.803^*)를 보였다. 유박 처리구(OC-B, OC-S, R+OC)의 작물 질소이용률은 화학비료와 통계적으로 유의한 차이를 보이지 않았다. 결론적으로, 개발된 유기자원 시비처방 시스템은 유기 벼 생산에 효과적이었으며, 해당 시스템이 유기 벼 재배 현장에서 유용하게 활용될 것으로 판단된다. 또한 추후 시스템 적용 대상을 다양한 밭작물을 대상으로 확대할 필요성이 있을 것으로 보인다.