• 상하수도학회지
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• 제14권2호
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• pp.147-156
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• 2000

In this study, the optimal operation parameters of MLE(Modified Ludzack-Ettinger) process treating the liquid supernatant separated from the slurry excreta of swine feedlot was studied as a promising biological treatment process. The nitrogen removal characteristics with different volume ratio between nitrification and denitrification reactor and the operational effect with different nitrogen loading rate, and different C/N($COD_{Cr}/TKN$) ratio were investigated. Based on the laboratory results, pilot MLE plant was operated to examine the effect of ambient temperature for five months including winter. The denitrification reactor which is 20% of total volume was proposed as the most optimal volume fraction for nitrification and denitrification. The optimum ratios of F/M and $F_N/M$ were increased with increase of the C/N ratio. However, optimum F/M ratio was changed more rapidly than $F_N/M$ ratio with increase of the C/N ratio. Therefore, MLE process is desirable to be controlled by F/M ratio in the range of high C/N ratio and by $F_N/M$ ratio in the range of low C/N ratio. Pilot MLE plant showed the higher removal efficiencies of COD and TKN in winter than in summer and was operated most stably at the temperature of $20{\sim}25^{\circ}C$ for mixed liqour.

• 식물조직배양학회지
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• 제28권6호
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• pp.311-315
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• 2001

담배 (Nicotiana tabacum L cv. Xanthi) 및 애기장대 (Arabidopsis thaliana cv. Col-0)에서 다양한 발달단계의 잎으로부터 원형질체를 분리하여 세포 크기와 엽록체의 크기 및 수의 관계를 조사하였다. 담배 원형질체의 지름이 15.6 $\mu\textrm{m}$ 이하인 작은 세포는 20여 개 이하의 엽록체를 가지고 있었는데, 엽록체의 평균 크기는 두께 0.93 $\mu\textrm{m}$, 길이 3.3$\mu\textrm{m}$로 나타났다. 잎이 신장되어 원형질체의 지름이 평균 30 $\mu\textrm{m}$에서 45 $\mu\textrm{m}$로 증가함에 따라, 엽록체는 두께 1.57 $\mu\textrm{m}$, 길이 5.55 $\mu\textrm{m}$의 크기로 일정하게 유지되었으나 엽록체의 수는 평균 42개에서 101개로 증가하였다. 이와 같이 담배에서 잎의 크기 또는 세포의 크기와 엽록체의 수 또는 부피는 비례관계를 나타냈고 동일한 경향이 애기장대에서도 관찰되었다. 세포 부피에 대한 총 엽록체의 부피의 비는 다양한 발달단계에서 담배는 10.5%, 애기장대는 32.5%로 일정하게 유지되었다.

• 원예과학기술지
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• 제29권3호
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• pp.201-210
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• 2011

This experiment was conducted to investigate physical and chemical characteristics by volume fractions of root media using peatmoss, perlite, and vermiculite, along with effects on the growth of pot chrysanthemums (Dendranthema ${\times}$ grandiflorum 'Vemini') in a C-channel mat irrigation system. To evaluate the physico-chemical properties of 20 root media, the bulk density, particle density, total pore space, pore space, ash content, organic matter, pH, and electrical conductivity were measured and data were analyzed using principal component analysis (PCA). PCA scores revealed that physico-chemical properties changed by the blending of peatmoss, perlite, and vermiculite. The 20 root media were divided into three main groups by hierarchical cluster analysis. At the end of the experiment, the pH and EC of the root media were measured from media divided into four layers. The pH of root media without plants showed a strong linear relationship and the pH of root media with plants increased exponentially. The change of EC in the root medium was indicated as a hyperbolic curve. Plant growth characteristics according to growth in the 20 root media were analyzed by PCA. It was found that the mixing ratios of the root media affected plant growth characteristics. Therefore, mixing ratio is an important factor for pot-plant production in a subirrigation system.

• 한국작물학회지
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• 제46권2호
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• pp.125-129
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• 2001

Eight vermiculite-based root media prepared with addition of complete fertilizer (2 g/L; N-$P_2$$O_5$-$K_2$O, 10-10-14) for potatoes (Solanum tuberosum L.) and a commercial root medium were evaluated in 2000 to develop the root media suitable for potato plug seedling production. The eight media consisted of various ratios of vermiculite, perlite, peatmoss, and compost. In addition, four rates (0, 1, 2, or 4 g/L) of the complex fertilizer for potato were added to a root medium (70% vermiculite, 10% perlite, 10% peat moss, and 10% compost by volume) to determine the optimum addition rate of the complex fertilizer for plug seedlings. Compost addition to the media increased plant height, the number of leaves per plant, and top and root fresh weight of 15-day old plug seedlings. The seedlings raised in root media containing compost produced significantly higher total tuber yield. Addition of the complex fertilizer to root media enhanced seedling growth and increased the number of tubers per plant and tuber yields. The results suggest that root media containing 50% vermiculite, 0 to 20% peat moss, 10% perlite, 20 to 40% compost, and 2 g/L complex fertilizer for potato appear suitable for potato plug seedling production.

• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3427-3432
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• 2014

This study introduces a new method of combining Imaging Differential Optical Absorption Spectroscopy (Imaging-DOAS) data and plume dispersion formulas for power plant emissions to determine the three-dimensional structure of a dispersing pollution plume and the spatial distributions of trace gas volume mixing ratios (VMRs) under conditions of negligible water droplet and aerosol effects on radiative transfer within the plume. This novel remote-sensing method, applied to a power plant stack plume, was used to calculate the two-dimensional distributions of sulfur dioxide ($SO_2$) and nitrogen dioxide ($NO_2$) VMRs in stack emissions for the first time. High $SO_2$ VMRs were observed only near the emission source, whereas high $NO_2$ VMRs were observed at locations several hundreds of meters away from the initial emission. The results of this study demonstrate the capability of this new method as a tool for estimating plume dimensions and trace gas VMRs in power plant emissions.

• Journal of Plant Biology
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• 제16권1_2호
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• pp.1-5
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• 1973

Six young trees of Alnus tinctoria grown in isolation, each having different growing stage, were selected and the surface area of their roots, stems and leaves was determined. Each of the roots of more than 0.2mm in diameter and stems was cut at intervals of 10cm and their surface area was calculated with 2$\pi$rl from the average diameter (2r) of both sections (upper and lower) by making cylindrical estimation of the cut pieces. The leaf area measured was only one side area, and the volume of cut piece and amount of dry matter of each organ were also measured. The percentage to the surface area of the whole plant body by each organ was 4-12% in root, 7-9% in stem and 69-89% in leaf, respectively. There was relatively a little individual difference. However, the surface area ratios of root and stem showed a slightly increasing tendency while that of leaf decreasing according to the growing stage. The ratio of sum leaf area index (LAIi) was 2.3-4.0$m^2$/$m^2$-and that of the surface area index(SaIi) was 0.16-0.33$m^2$/$m^2$, respectively. It has been known that the stem surface area(SAI) to the leaf area index(LAI) is within the range of 31-53%, but the SAIi is within the range of 8-11% of the LAIi.

• 한국환경과학회지
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• 제24권2호
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• pp.189-196
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• 2015

This study was performed to identify the effect of mixed bed soil on growth of aerial parts and root zone of daughter plants for nursery field strawberry seedling raising with expanded chaff. The plant height and leaf area of daughter plants were highest or largest in the mixed soil of ERH +RH (100:0, v/v), followed by ERH+RH (75:25). The higher the mixing ratio of RH, the shorter the plant height or the smaller the leaf area. A similar tendency was observed in fresh weight. Within a root diameter of 0-0.4 mm and a root height range of 0.4-0.8 mm, root surface area and volume were statistically significantly better with treatment of ERH+RH (100:0, v/v) compared to those of roots treated with ERH+RH (75:25), ERH+RH (50:50) and ERH+RH (25:75). The growth rate of aerial parts and root zone of daughter plants were noticeably lower in two mixing ratios of 50:50 and 25:75. According to the mixing ratios of ERH+CD surface treatment, the number of roots was greatest in plants treated with ERH+CD (80:20, v/v) and ERH+CD (85:15) on August 1. However, the number of roots was highest in plants treated with ERH+CD (85:15, v/v) on August 15. Root length was longest in the plant with no treatment, and drastically shortened from ERH+CD (90:10, v/v) in both surface and mixed treatment. Although root weight showed a significant difference in ERH+CD (90:10, v/v) treatment, its increase was gradual. The rate of root growth was highest in ERH+CD (85:15). These study findings suggest that the content ratios of mixed soil ERH+RH (75:25, v/v) or below and ERH+CD (85:15) are thought to be desirable for the production of high quality seedlings.

• 한국산학기술학회논문지
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• 제16권11호
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• pp.7990-8000
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• 2015

식물공장은 환경적 조건을 조절하여 계절이나 장소에 관계없이 농산물을 일정하게 생산하는 식물재배 시스템이다. 식물공장에 있어서 내부의 열 유동은 식물공장의 중요한 변수이다. 본 논문에서는 다층 재배선반을 갖는 하이브리드 식물공장 내의 열유동 특성을 수치 시뮬레이션을 통해 연구하였다. 열 유동 특성의 수치해를 얻기 위해 유한체적법(Finite Volume Method)을 이용하였다. 수치해석 모델에 있어서는 저 레이놀드수(low Reynolds number) ${\kappa}-{\epsilon}$ 난류모델을 이용하였으며, 해석방법으로는 비압축성 점성유동 영역과 압력경계 조건을 사용하였다. 수치해석에 있어, 3종류의 유입 공기속도와 재배선반의 위치변화에 따른 식물공장 내의 열유동 특성을 상용 프로그램인 Solid Works Flow simulation을 사용하였다. 수치해석을 통한 결론은 다음과 같다. 첫째, 송풍기를 통한 식물공장 내의 유입 공기속도를 1.6 m/s로 하였을 때, Case 3의 재배선반 배치가 비교적 균일한 온도 분포를 나타내었고, LED광만을 사용한 Case 1의 배치는 시험베드(test bed) TB2와 TB3 영역의 낮은 온도분포로 인하여 서큘레이터 등을 통한 추가적인 온도 제어가 필요할 것으로 판단되었다. 둘째, 식물재배 LED 인공광(DYLED47)의 청색광과 적색광의 비율을 1:1로 100% 구동 시, 재배선반의 평균 온도가 약 $3^{\circ}C$ 증가하였다. 본 논문은 한국산학기술학회 논문지 심사용 투고요령입니다.

• 생물환경조절학회지
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• 제16권2호
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• pp.108-114
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• 2007

피트모스를 기본으로 한 3종의 혼합 고형배지의 물리화학적 특성 분석과 3종의 배지 및 양액농도(EC $0.5{\sim}1.5dS{\cdot}m^{-1}$가 토마토(일광 토마토 ) 플러그묘의 초기생장(파종 후 31일째)에 미치는 영향을 조사하였다. 혼합배지의 물리화학적 특성은 피트모스의 혼입비율이 많아질수록 보수력이 증가하였고, 공극율은 모든 혼합 배지 처리에서 80% 이상이었다. pH와 EC피트모스의 혼입비율이 많을수록 pH는 낮아졌고, EC는 전반적으로 $3.6{\sim}4.8dS{\cdot}m^{-1}$ 정도의 범위로 비교적 높게 나타났다. 양질의 토마토 플러그묘 생산에 가장 좋았던 혼합배지는 피트모스:왕겨:훈탄:부숙톱밥:펄라이트=25:10:25:20:20(v/v)였다. 관비 양액농도(EC)는 대조구(수돗물, EC $1dS{\cdot}m^{-1}$)에 비해 관비 양액농도(EC 0.5, 1.0, $1.5dS{\cdot}m^{-1}$)가 높아질수록 초장, 엽면적 및 총건물 생산량 등이 현저히 높아졌다.

• 원예과학기술지
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• 제35권3호
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• pp.289-299
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• 2017

The objective of this study was to determine the effect of replacing perlite (PL) with pellets processed with poultry feather fiber as an inert material to prepare growing medium. The growth and flowering of Salvia splendens 'Vista Red' grown in individual growing medium $Biosangto^{(R)}$, peat moss (PM), PL, and two pellets (P45-1 and P45-2) were evaluated. Peat moss was mixed with PL, P45-1, or P45-2 at various ratios (1:0 to 1:3 or 3:1 by volume) to investigate the feasibility of replacing PL with pellets. Nutrient composition of the growing medium and leaf tissues was analyzed. The number of florets, inflorescence length, plant height, and fresh weight of plants grown in media containing P45-1 or P45-2 were reduced compared to those grown in individual growing medium PM or PL. As the mixing ratio of P45-1 or P45-2 to PM was higher, the growth of salvia, such as inflorescence length, plant height, number of leaves, and fresh weight was inhibited. Our results indicate that mixing three parts PM with one part of P45-1 (PM/P45-1/3:1) or P45-2 (PM/P45-2/3:1) accelerated flowering and increased the number of florets and leaves compared to other mixing ratios of PM and pellets media. The concentrations of phosphorus (P), calcium (Ca), boron (B), iron (Fe), and copper (Cu) in individual growing medium PL, P45-1, and P45-2 were significantly lower than those in PM. The concentration of N was the highest in leaves of plants grown in P45-1 or P45-2 amended media, and the concentrations of P, Ca, and zinc (Zn) in leaves were lower in individual growing medium P45-1 or P45-2 than in PM and PL. The pH of PM/P45-1/3:1 or PM/P45-2/3:1 media was maintained at optimal level (5.8-5.9) and the concentrations of macro- and micro-elements in the media and leaves were considered to be optimal levels. Therefore, mixing three parts PM with one part P45-1(PM:P45-1/3:1) or P45-2 (PM:P45-2/3:1) is recommended for improved growth and flowering in salvia. This suggests that P45-1 or P45-2 can replace PL as an inert material to prepare growing medium.