• Journal of Plant Biology
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• 제22권3호
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• pp.63-69
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• 1979

The plant growth and net production, the nitrogen uptake and recycling, the nitrogen mobility and allocation to each organ, and the nitrogen utility from the Italian rye grass field during the population development were analyzed in comparison with different clipping treatments. The maximum dry matter standing crop and nitrogen quantity of harvest increased significantly, however, the annual amounts of dry matter and nitrogen assimilation showed little variations with increasing clipping frequencies. Plants treated with frequent clippings allocated relatively more nitrogen to leaves and less to roots during the experimental period. The amount of recycling of nitrogen decreased considerably due to frequent clippings. The annual averages of nitrogen utility indices changed in inverse relation to the nitrogen availability; such as 63, 58, 44 and 35 for C, A, M and J plots, respectively.

• 한국연초학회지
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• 제16권1호
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• pp.43-52
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• 1994

To investigate the factors of the improvement of cultivation methods according to the plant type, three Burley tobacco cultivars were done. Experiments on the variability of plant type and factors representing the productivity and quality of the cultivar were subsequently carried out in relation to different fertilizer levels. Results are summarized as below. Use of more fertilizer resulted in higher plant height and longer leaf length but smaller mean leaf inclination(MLI). The horizontal leaf area distribution became greater in parts distal to the stem and the vertical leaf area distribution became greater in lower half than in upper half as the amount of fertilizer applied was increased. Br. 49 was the largest but Br. 21 and NTN 77 were similar with respect to both CGR and NAR. The yield was greater in larger MLI cultivars. These three characteristics became greater when the tobacco were heavier in the cultivars of larger MLI and increased with higher amount of fertilizer. Harvest index became greater as the amount of fertilizer decreased but not significantly differ among the cultivars. Total nitrogen content and nitrate - form nitrogen content were greater, more amount of fertilizer, and larger MLI cultivar plots. Total nitrogen content was higher in upper leaves. The filling power of tobacco leaves decreased but combustibility of leaves showed not significant trend as fertilizer application level increased.

• 한국초지조사료학회지
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• 제15권4호
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• pp.297-302
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• 1995

The objective of this experiment was to compare the dry matter intake, nutrients digestibility, nitrogen and energy utilization of hehage among the orchardgrass(OG) pure, orchardgrass(OG)-red clover(RC) mixture and complex rnixtures(C. mix) by Korean native goat. The results obtained were surnmerized as follows: 1. Crude protein(CP) content was higher in OG-RC and C. Mix diets than in OG pure diets(P<0.05). NDF content was higher in OG pure diets than other diets(P<0.05). But ADF, Lignin contents and gross energy did not differ among all diets. 2. Dry matter intake by Korean native goat tend to be high in OG-RC diets, and low in OG pure diets. But there was no significant difference statistically. Dry matter and cellular constituents digestibilities were higher for OG-RC and C. Mix diets than OG pure diet, but CP and NDF digestibilities were no significant difference among diets. 3. The amount of nitrogen consumed amount by Korean native goat in the OG-RC diet was higher than other diets. But, due to largely relative urinary and fecal nitrogen loss, Apparrently digested nitrogen and retained nitrogen percents were not significant difference among diets. 4. The amount of energy consumed by Korean native goat in OG-RC diet was higher than other diets. But, due to largely relative urinary and fecal energy loss, digestable energy percent was lower than C. Mix diets. But.metabolic energy percent was no significant difference among diets. Therefore, there was no significant differences among sward types for the utilization of nitrogen and energy by Korean native goats.

• 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%.

• 한국작물학회지
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• 제40권4호
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• pp.512-517
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• 1995

질소의 추비가 품질특성에 미치는 영향을 조사하기 위하여 1993년 일본의 동북농업시험장의 화산회토인 포장에서 미유기 보리를 공시품종으로 하여 재생기, 유효분벽기 그리고 출수기에 유안을 질소 성분량으로 2 또는 4kg을 추비하였다. 도종율 백도 조단백질 등을 조사한 결과를 요약하면 다음과 같다. 1. 55% 도종기간은 2kg을 추비하면 길어지나 추비 시기간에는 차이가 없었다. 백도, 경도 그리고 도종율도 추비에 의한 차이는 없었다. 2. 원맥의 조단백질함량은 추비에 의하여 증가하였으나 시기간에는 차이가 없었다. 3. 원맥의 조단백질함량과 55% 도종기간과는 정의 상관관계가 있었으나 8분 도정림의 백도와는 상관이 없었다. 4. 8분 도종율 및 8분도정립의 백도와는 부의 상관관계가 있었고, 8분 도종율과 55% 도종시간과는 정의 상관관계가 있었다. 백도 형질간에는 상관관계가 없었다. 5. 주사형 전자현미경에 의한 미세구조관찰에서 추비처리에 의한 Protein matrix의 차이는 없었다.

• 한국작물학회지
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• 제28권1호
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• pp.89-93
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• 1983

수도에서 질소시용량에 따른 Ethylene 생성량의 품종간 차이를 알아보기 위하여 만석벼 외 5품종을 공시하여 질소시용량을 $N_0,\;N_1,\;N_2$등 3수준으로하여 유묘기에 인공기상실에서 시험을 실시한 바 그 결과를 요약하면 다음과 같다. 1. 질소시용량 증가에 따른 도체내의 질소함유율이 높아짐에 따라 Ethylene 생성량은 감소됨을 인정할 수 있었다. 2. 엽신에서 Ethylene 생성량의 품종간 차이는 현저하여 만석, 팔달이 많았고, 유신, IR-36이 적었다. 3. Ethylene생성량이 많은 품종(만석, 팔달)은 질소표준구$(N_1)$에 비하여 무비구$(N_0)$의 Ethylene 생성량이 급증하였고, Ethylene 생성량이 적은 품종(유신, IR-36)은 다비$(N_2)$에서 급감하는 경향이였다. 4. 도체내의 질소함유율에 따른 Ethylene생성량의 품종간 차이는 동일품종에서는 질소함유율이 많으면 Ethylene생성량이 적어지나 품종이 다를 경우에는 질소함유율이 많은 품종에서 Ethylene 생성량도 많은 경향이였다.

• 한국작물학회지
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• 제47권6호
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• pp.486-491
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• 2002

일반계인 추청벼, 화성벼와 통일계인 남풍벼를 공시하여 질소(5수준), 분시방법(2수준) 및 유수형성기 차광처리(3수준)에 따른 영화수, 지경 분화수, 퇴화수 등 영화수 구성요소, 질소함량, 건물중, 비구조탄수화물 등을 조사하여 경엽의 질소보유량 및 건물중과 영화수 구성요소와의 관계, 그리고 영화형성 효율의 품종간 차이를 검토하였으며 그 결과를 요약하면 다음과 같다. 1. 단위면적당 1차지경수는 유수분화기와 그 후 15일 및 출수기, 3차지경수는 유수분화 후 15일 출수기의 경엽중의 질소보유량과 유의한 정의 상관을 나타내었다. 단위면적당 1차지 경수는 유수분화기의 경엽중, 2차지경수는 유수분화 후 15일의 경엽중과 유의한 정의 상관이 있었다. 2. 단위면적당 2차지경 퇴화수와 영화의 퇴화수는 유수분화 이후 15일간의 경중 증가량, 경중의 비구조탄수화물 증가량, 그리고 이때의 비구조탄수화물 함량과 유의한 부의 상관을 나타내었다. 3. 단위면적당 영화수는 출수기의 경엽중 질소보유량, 경업의 건물중과 유의한 정의 상관관계가 있었다. 4. 출수기 경엽중의 질소보유량당 영화수로 표현한 영화형성호율은 통일계인 남풍벼가 일반계인 화성벼와 추청벼보다 높았으며, 영화형성효율은 건물중이 증가함에 따라 감소하였다. 이 기간중 엽의 건물중과는 상관관계가 없었으나 경의 건물 중 증가에 따라서는 모든 품종에서 유의하게 감소하였다. 생식생장기간 동안의 건물 중 증가에 따른 영화형성효율은 구조 탄수화물의 증가에 따라서 감소되었으며, 출수기 경중의 저장 탄수화물 함량이 높은 경우 영화형성효율이 높아지는 경향이었다.

• 상하수도학회지
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• 제21권3호
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• pp.295-303
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• 2007

Nitrogen compounds in municipal wastewater can be divided into biodegradable and nonbiodegradable fractions with biodegradability. Biodegradable nitrogen compounds can be removed through biological nitrification and denitrification processes, and nonbiodegradable nitrogen compounds affect the effluent quality of biological nutrient removal processes. The amount of nitrifiable nitrogen compounds, which are the sum of ammonia and biodegradable organic nitrogen, has been estimated by respirometry. Respirometry shows good estimation of the concentration of nitrifiable nitrogen when a synthetic sample of ammonium chloride is dosed. The estimated concentration of nitrifiable nitrogen compounds in municipal wastewater is close to ammonia concentration in municipal wastewater, but it is lower than that for the synthetic sample. If nitrogen assimilated into cell synthesis of nitrifiers and heterotrophs is considered, the total amounts of nitrifiable nitrogen compounds, which are nitrified and assimilated, could be more accurately estimated. The concentration of nitrifiable nitrogen compounds, which are biodegradable, is about 31 mg N/l, and this is 119% of ammonia and 94% of total nitrogen. Ammonia, nitrate, biodegradable organic nitrogen, and nonbiodegradable nitrogen are about 79%, 1%, 15%, and 5% of the total nitrogen in municipal wastewater, respectively.

• 아시안잔디학회지
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• 제9권4호
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• pp.265-273
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• 1995

This investigation is carried out to clarify the cycles of nitrogen in the grassland ecosystems of Zoysia japonica and a Miscanthus sinensis on Mt. Kwanak. The hasic differential equation for the rate of change of nitrogen storage is illustrated hy huild-up and turnover of organic nitrogen, particularly in the ecosystems. The turnover velocity fractions of nitrogen for the Z. japonica and M .sinensis grasslands were k= 0. 181 and k=0. 166, respectively. The times required to reach 50, 95 and 99 percent of the steady state levels and turnover values of nitrogen on the grassland floors were 3.85, 16.67 and 27.78 years in the Z japonica grassland and 4.08, 17.65 and 29.41 years in the M sinensis grassland. The amount of annual cycles of nitrogen are 560.2 g /$m^2$ in the Z.japonica grassland and 654.1 g /$m^2$ in the M. sinensis grassland. Key words : Zsysia japonica Alisca nthus sinensis, Mt. Kivanak, Nitrogen cycle.

• 한국정밀공학회지
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• 제17권9호
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• pp.196-201
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• 2000

There is a great demand for reducing the amount of material used in mass-produced plastics parts for material cost constitutes a large percentage of the total cost of a product up to 75% It may be noted that the price of plastics is directly related to the price of petroleum. Material reduction therefore decreases the amount of oil needed for the manufacture of plastics and thus help conserve this natural resource. Therefore microcellular foaming process(MCPs) was studied for solving this problems alternatively in 1980's at M. I. T. Until now in microcellular plastics processes carbon dioxide gas was mainly used for microcellular foaming Because carbon dioxide has more solubility than any other gases such as nitrogen gas or helium gas. The purpose of the this research is measurement of changing of the microcellular plastics' weight by using nitrogen gas in injection molding an comparing weight reduction of microcellular foamed plastics for using carbon dioxide gas with nitrogen gas.