• 한국초지조사료학회지
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• 제15권4호
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• pp.238-244
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• 1995

The objective of this study is to obtain the basic data for investigating the effects of organic reserves on winter survial or regrowth yield. Forage rape(Brassica napus L.) was sown on Sep. 1, 1994. Experimental plots were divided into three replicates under 6 different cutting dates(l0 days interval from Oct. 15 to Dec. 4). Field-grown palnts were sampled on the each cutting date and on the wintering period (Jan. 16) to analyze the nitrogen and non-structural cahohydrate reserves. The rate of winter survival and regrowth yield were also measured in the spring of next year. On the before wintering, dry matter yields were 152, 274, 500, 718, 776 and 981 kg/lOa, respectively, from the cutting date on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. Cmde protein yield significantly increased as cutting date was later until Nov. 14, thereafter a significant increase did not occured. Nitrogen and starch contents per plant significnatly increased as the cutting date was later. The increasing rate of starch was greatly higher than that of nitrogen. On the wintering period, nitrogen reserves in mts were 85.3, 68.8, 47.6, 28.3, 44.3, and 55.3 mglplant, and starch reserve were 11 1.3, 75.3, 39.3, 19.6, 26.4 and 34.6 mglplant, respectively, in the plots cut on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. It showed that carbohydrate reserves were much highly utilized than nitrogen reserves during wintering period. The rates of winter survival were 91, 83, 46, 22, 35 and 43% and regrowth yields were 692, 545, 316, 84, 127 and 140 kgD.M/lOa, respectively, in each plots. The highly significant correlation (p<0.01) between the level of organic reserves and the rate of winter survival or regrowth yield were obtained.

• 한국물환경학회지
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• 제23권5호
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• pp.607-612
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• 2007

In this study, we investigated the variations of the kinetic coefficients and Chemical Oxygen Demand (COD), N and P mass used for assimilation of a sequencing batch reactor (SBR) system with the variation of SRTs; SRTs of 7.5, 10.0, 12.5, 15.0 and 20.0 days were tested in one cycle of SBR operation to determine the optimum conditions for the operation of the SBR and estimate its COD, nitrogen and phosphorus removal efficiencies. The SBR system was operated under the conditions as follows: an operation time of 6 hours per cycle, a hydraulic retention time (HRT) of 12 hours, an influent COD loading of $0.4kg/m^3/day$, and an influent nitrogen loading of $0.068kgT-N/m^3/day$. The yield coefficient (Y) and decay rate coefficient ($k_d$) were estimated to be 0.4198 kgMLVSS/kgCOD and $0.0107day^{-1}$ by calculating the removal rate of substrate according to the variation of SRT. Considering total nitrogen amount removed by sludge waste process, eliminated by denitrification, and in clarified water effluent with reference to 150 mg/cycle of influent nitrogen amount, the percentage of nitrogen mass balance from the ratio of the nitrogen amount in effluent (N output) to that in influent (N input) for Runs 1~5 were 95.5, 97.0, 95.5, 99.5, and 95.5%, respectively, which is well accounted for, with mass balances close to 100%.

• 한국물환경학회지
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• 제33권4호
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• pp.409-415
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• 2017

This study aims to evaluate the effect of capping materials on blocking pollutant elution from contaminated sediment to water body. Experiments were carried out under conditions in which the elution rate was intensified artificially using compost with high concentration of organic compound and nutrient salts instead of sediments. Activated carbon (AC), modified activated carbon (MAC), P. putida immobilized activated carbon (PBAC) and effective microorganisms immobilized activated carbon (EBAC) were used as capping materials. Zeolite (ZT) and two kinds of commercially available microorganisms immobilized zeolite products (ZC, ZN) were used for comparison experiment. The elution rate of organic compound, nitrogen and phosphorus were compared with that of control experiment. The experiments were conducted for 56 days. Concentrations of chemical oxygen demand, total nitrogen, and total phosphorus were measured to use the comparison of release rate of organic compound, nitrogen and phosphorus. From the experimental results, AC based materials showed better performance to block the elution of organic compound and nitrogen than ZT based materials. Although ZT based materials were more effective than AC and PBAC to block phosphorus, MAC and EBAC showed the best performance of phosphorus elution blocking among the all candidate materials. In conclusion, EBAC is considered as the most effective capping materials, because organic compound, nitrogen and phosphorus will be degraded continuously by EM in the long term.

• 한국환경생태학회지
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• 제19권1호
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• pp.1-8
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• 2005

창포를 이용하여 질소와 인의 농도별, 식물의 생장단계별, 오염수의 체류시간별로 질소와 인의 제거효과를 분석하였던 바, 그 결과를 요약하면 다음과 같다. 체류 1시간 후에 수중의 질소와 인의 함량을 현저히 감소시켰으나, $2\~4$시간 후에는 감소율이 극히 낮았다. 이러한 현상은 식물의 생장초기, 생장기, 생장최성기에서 동일하였다. 수중에 질소와 인의 함량이 많을수록 제거율이 높았고, 인보다는 질소의 제거효과가 크게 나타났다. 생장최성기에 가장 많은 질소와 인을 제거하였고 다음으로 생장기, 생장초기의 순이었으나, 생장단계간의 차이는 극히 작았다. 동일 포트에 4일 동안 체류시킨 것보다 2일 체류 후에 다른 포트로 시험수를 옮긴 것이 질소와 인의 제거율이 약간 높았다.

• 한국수산과학회지
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• 제29권6호
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• pp.779-786
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• 1996

The main purpose of this study was to estimate the role of dissolved inorganic nitrogen (DIN) released from sediment and denitrification process in sediment on the nitrogen budget of Hiroshima Bay by means of collecting data on distributions and budgets of nitrogen and phosphorus in the bay, DIN fluxes across sediment-water interface and denitrification rates in the sediments of the same area. The TN : TP and DIN:DIP atomic ratios of the discharged freshwater were about 26 and 21, respectively. The standing stocks in the seawater of the TN : TP atomic ratio varied from 8 to 14 with an annual mean value of 11, while the DIN : DIP atomic ratio varied from 10 to 15 with an annual mean value of 12 in the bay. The residence time of nitrogen and phosphorus were estimated to be about 109 days and 200 days in the bay, respectively. The proportion of DIN released from sediment and denitrification rate to the loading of total nitrogen into Hiroshima Bay were $45\%\;(37\~82\%)\;and\;13\%(0.0\~37\%)$, respectively, and the amount of nitrogen through denitrification process was 6.5 times larger than the outflow of nitrogen from the bay. The results show that DIN released from sediment and denitrification process in sediment play important roles on the nitrogen budget in Hiroshima Bay.

• 한국작물학회지
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• 제44권1호
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• pp.11-19
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• 1999

This experiment was conducted with nine wheat geno-types to choose the wheat which has excellent early vigour. 'Vigour 18' and 'ZL 59A' are excellent in the long coleoptile genotype, while 'Amery' and 'Janz' are excellent in the short coleoptile genotype. Responding to the growth stage and nitrogen level, Vigour 18 is predominant in the long coleoptile genogype, while Janz in the short coleoptile genotype. Responding to sowing density and nitrogen level, the higher the sowing density was, the shorter the leaf area of Vigour 18 and Janz. Also the leaf area turned out to larger in the plot fertilized with high nitrogen than in the plot fertilized with low nitrogen. This is true of leaf weight and root weight. Concerning specific leaf area (SLA) and leaf area ratio (LAR), the higher the sowing density was, the SLA tended to grow larger, while the SLA grew larger in the plot fertilized with low nitrogen, as were found in Vigour 18 and Janz. The roots of long coleoptile genotype, Vigour 18, turned out to grow longest on the plot sown with 3 seeds. While the roots of short coleoptile genotype, Janz, grew longest on the plot sown with 2 seeds. The relative growth rate (RGR) was the same at low N rates and high N rates. The RGR was 0.071 and 0.072 g $g^{-1}d^{-1}$ at low N rates and high N rates. The partitioning of RGR into net assimilation rate (NAR) and LAR showed that the average LAR at low N rates was similar to the LAR at high N rates. Variation within each cultivar in the LAR and NAR was small relative to the difference between them at low N rates and high N rates. Above ground mass was 8.2 mg greater at high N rates than low N rates, whereas leaf area was 0.05 $\textrm{m}^2$$kg^{-l}$ greater at high N rates than low N rates. The NAR was similar at low N rates and high N rates, whereas LAR was greater at high N rates (0.05 $\textrm{m}^2$$kg^{-l}$); variation in SLA was responsible for the variation in NAR and LAR both at low N rates and high N rates. NAR was more closely associated with the reciprocal of SLA.

• 한국작물학회지
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• 제41권5호
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• pp.514-520
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• 1996

벼 어린모 상자육묘시 상토종류별 질소시비량이 묘생육에 미치는 영향을 검토하여 상토종류별 적정 시비량을 구명하고자 동진벼를 공시하고 논 흙 및 산흙에 요소로 질소를 상자당 0, 1, 2, 3g 시용하고 평균 $25^{\circ}C$의 온실에서 육묘하여 묘생육을 컴토한 결과는 다음과 같다. 1. 출아율은 시비량이 많을수록 저하되었고 논흙에 질소 3g/상자 시용에서는 출아율이 현저히 낮아졌고, 논흙이 산흙보다 시비량 증가에 따른 출아율 저하가 컸다. 2. 성묘율은 시비량이 많을수록 감소하여 산흙에서는 질소 2g/상자, 논흙에서는 1g/상자 까지 90% 이상의 입모율을 보였으나 그보다 시비량이 많으면 입모율이 현저히 저하되었다. 3. 모의 초장은 산흙에서는 질소시비량이 많을수록 길었으나 논흙에서는 2>3>1>0g /상자의 순으로 길었으며, 엽수는 산흙의 6일묘에서는 3>2>1>0g /상자의 순으로 많았으나 8일묘 이상에서는 무비를 제외하고는 시비량간에 별 차이가 없었다. 4. 모의 건물중은 산흙에서는 시비량이 많을수록 무거웠으나 논흙에서는 시비량 2g에서 가장 무거웠다. 5. 배아잔존율은 상토종류간에는 별 차이가 없었으나 두 상토 모두 시비량이 많을수록 적어지는 경향 이었다. 6. 뿌리량은 산흙에서는 1>0>2>3g/상자의 순으로 많았고, 논흙에서는 0>1>2>3g/상자의 순으로 시비량이 많을수록 적었으며 부농상토가 가장 적었다. 7. 맷트의 인장력은 산흙에서는 1>0>2>3g/상자의 순으로 컸고, 논흙에서는 시비량이 적을수록 컸고 부농상토가 가장 적었으며, 맷트 형성 정도는 시비량이 적을수록 양호하였다. 이상 입모상태, 모생육 및 맷트 형성 정도를 고려할 때 어린모 상자육묘의 적정 대소 시비량은 산흙 2g/상자, 논흙 1g/상자이라고 판단된다.등이 높은 조성을 보였고 무차광구에 비하여 차광구(55%)에서 높았으며 유기물 시용량이 많을수록 현저히 증가하는 경향이었다. 8. 종합적으로 볼 때 지상부 및 지하부 생육은 차광에 비해 무차광에서 양호하였으나 향기성분은 무차광에 비하여 차광에서 높았고 유기물 시용량간에도 시용량이 증가할수록 방향성이 높아 고품질의 더덕을 생산하기 위해서는 차광과 유기물 다량시용을 병행해야 할 것으로 판단되었다.과할수록 감소하는 경향을 보였다., 산파는 포장도복으로 크게 낮아 경운 이질의 87~81%정도였다.형간에는 기계이앙이 건답직파보다 우수하였고, 비종간에는 속효성 비료보다는 완효성 비료에서, 그리고 질소의 감비보다는 100%시용구에서 보다 우수한 경향을 보였다. 따른 분얼체계와 동신엽, 동신분얼의 수량성은 표준구와 50%증비구는 0, 1, 2, 11, 3, 21, 12, 22, 4, C의 순위였으나 100%증비구에서는 주간보다 1차분얼의 1이 무겁고 3보다 11이 무거웠다.섭취하였고, 탄수화물은 농촌지역 여고생이 대도시 지역 여고생에 비하여 유의적으로 많이 섭취하였다. 지역별 여고생의 에너지섭취 비율은 탄수화물 : 단백질 : 지방의 섭취 비율이 대도시 60.75% : 16.4% 22.9%이며, 중소도시가 62.7% : 15.7% : 21.5%,농촌이66.8% : 14. l% : 19.1%이었다. 영양지식의 정확도나 인지도는 영양소 섭취와 유의적인 상관관계가 없었으며, 대도시 여고생의 식습관은 칼슘, 비타민 A 비타민 C 섭취와 유의적인 상관관계가 있으며, 중소도시 여고생의 식습관은 영양소 섭취와의 상관관계가 유의적이지 않았다. 농촌지역 여고생의 식습관은 단백질, 인 철, 비타민 B$_1$, 비타민 B$_2$, 나이아신에 유의적인 상관관계를 가지고 있다. 이와 같은 결과로 볼 때 대도시 지역 여고생의 영양지식은 식습관과 관계가

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.29.1-29.1
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• 2008

The temperature control system which is using liquid and gaseous nitrogen has been known as the most economical system to simulate space temperature condition due to relatively not expansive price of the liquid nitrogen (less than 0.2 USD per liter). And, among these systems, the closed loop system which circulates compressed nitrogen gas come from sprayed liquid nitrogen by blower and makes a target temperature with heat from an electrical heater and flow rate of liquid nitrogen is prevail all over the world. But, this complete closed loop system requires expansive equipments such as blower, heater, and liquid nitrogen injector, and special maintenance on the system. Therefore, KARI is developing efficient and simple open loop system which utilizes liquid and gaseous nitrogen with eliminating a special blower and other expansive units. In this study, this open loop system with more efficiency and flexibility will be designed and introduced.

• 한국환경복원기술학회지
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• 제14권6호
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• pp.17-27
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• 2011

Prunus serrulata var. serrulata f. spontanea (E. H. Wilson) C. S. Chang was treated with dried swine excrement at various concentration levels, and their growth reactions and the contents of total kjeldahl nitrogen and total phosphoric acid were analyzed. The result is as follows; 1. When the plants were treated with 0.25% of dried swine excrement, the seed germination rate of Prunus serrulata var. serrulata f. spontanea was higher than that of the control. However, it showed a tendency to decrease when the treatment concentration got higher than 0.25%. 2. The growth rate of species was highest when they were treated with 0.25% of dried swine excrement. It tended to decrease with higher treatment concentration than 0.25%. Significant difference was clear between the control and the experimental plants of Prunus serrulata var. serrulata f. spontanea. 3. The contents of nitrogen and phosphoric acid in Prunus serrulata var. serrulata f. spontanea also got higher as the concentration of dried swine excrement increased. However, the content of total kjeldahl nitrogen was highest in the leaves, and followed by the roots and stems. In contrast, the content of total phosphoric acid were highest in the roots, and followed by the leaves and stems. Therefore, stems had the lowest contents of both nitrogen and phosphoric acid. 4. The contents of total kjeldahl nitrogen and total phosphoric acid in the soil were measured before and after the growth experiment of Prunus serrulata var. serrulata f. spontanea treated with dried swine excrement. The contents of nitrogen and phosphoric acid significantly decreased after the experiment. In conclusion, the contents of total kjeldahl nitrogen and total phosphoric acid accumulated in the plants increased as the concentration level of dried swine excrement got higher. The seed germination and plant growth rates were best at 0.25% treatment of dried swine excrement. The treatment of dried swine excrement may bring high effects on increasing the plant growth rate but could damage the plants with higher concentration than they need. Different optimal concentration levels of dried swine excrement for different plants should be found before it is used as fertilizer.

• 한국응용과학기술학회지
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• 제33권4호
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• pp.795-801
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• 2016

본 연구는 응집제로 calcium alginate를 이용한 질산성 질소 처리에 관한 연구이다. 질산성 질소를 제거하기 위한 방법으로는 역삼투법, 이온교환수지법, 전기투석법, 생물학적 방법 등이 있지만 본 연구에서는 응집 침전시키는 방법으로서 질산성 질소를 처리하고자 하였다. 응집제로 이용한 calcium alginate가 킬레이트 결합을 형성하여 질산성 질소를 응집 침전시킬 것으로 예상하고, 응집제의 성분, 응집 반응시간, 응집제의 몰비, 응집제의 주입율에 따라 질산성 질소가 제거되는 경향을 보았다. 또한 FE-SEM과 EDS(Energy Dispersive X-Ray Spectrometer)를 통하여 응집반응 후 침전물의 구조 및 구성성분비를 분석함으로써 질산성 질소가 Calcium-nitro-alginate 형태로 제거되는지를 확인하였다. 그 결과 반응시간은 60분, 응집제의 몰비는 1:1일 때, 응집제의 주입율은 합성폐수의 2 %일 때 질산성 질소의 제거율이 최대 56.7 %로 나타났다.