• Environmental Engineering Research
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• 제25권3호
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• pp.274-280
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• 2020

The marine sediment sustains from the anoxic condition due to increased nutrients of external sources. The nutrients are liberated from the sediment, which acts as an internal source. In hypoxic environments, anaerobic respiration results in the formation of several reduced matters, such as N₂ and NH₄⁺, N₂O, Fe²⁺, H₂S, etc. The experimental results have shown that nitrogen and sulfur played an influential, notable role in this biogeochemical cycle with expected chemical reductions and a 'diffusive' release of present nutrient components trapped in pore water inside sediment toward the bulk water. Nitate/ammonium, sulfate/sulfides, and ferrous/ferric irons are found to be the key players in these sediment-waters mutual interactions. Organonitrogen and nitrate in the sediment were likely to be converted to a form of ammonium. Reductive nitrogen is called dissimilatory nitrate reduction to ammonium and denitrification. The steady accumulation in the sediment and surplus increases in the overlying waters of ammonium strongly support this hypothesis as well as a diffusive action of the involved chemical species. Sulfate would serve as an essential electron acceptor so as to form acid volatile sulfides in present of Fe³⁺, which ended up as the Fe²⁺ positively with an aid of the residential microbial community.

• 한국자원식물학회지
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• 제22권6호
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• pp.513-517
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• 2009

Seed mustard is high in nutrient quality and grows continuously under cold condition. Accordingly, it possessess high potential to bring about more efficient use of land when it is grown as a seasonings crop at paddy field in winter season. Recently, Seed mustard has aroused people‘s interest as a catch crop. The purpose of this trial is to examine productivity and chemical components of seed mustard and to select suitable variety in the southern area of Korea. Seed-mustard cv. Yeongsanpo local showed higher seed yield than any other varieties used in the experiment. It showed relatively high content of Oil, Protein, Ash, Carbo, $P_2O_5$, $K_2O$, Ca and T-N. The heritabilities of all the characters were estimated to be high. Therefore, it was concluded that Youngsanpo local was the most suitable variety with high yield and high nutrient quality at the southern area of Korea.

• Journal of Microbiology and Biotechnology
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• 제31권1호
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• pp.104-114
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• 2021

Petroleum-contaminated soil is considered among the most important potential anthropogenic atmospheric methane sources. Additionally, various rhizoremediation factors can affect methane emissions by altering soil ecosystem carbon cycles. Nonetheless, greenhouse gas emissions from soil have not been given due importance as a potentially relevant parameter in rhizoremediation techniques. Therefore, in this study we sought to investigate the effects of different plant and soil amendments on both remediation efficiencies and methane emission characteristics in diesel-contaminated soil. An indoor pot experiment consisting of three plant treatments (control, maize, tall fescue) and two soil amendments (chemical nutrient, compost) was performed for 95 days. Total petroleum hydrocarbon (TPH) removal efficiency, dehydrogenase activity, and alkB (i.e., an alkane compound-degrading enzyme) gene abundance were the highest in the tall fescue and maize soil system amended with compost. Compost addition enhanced both the overall remediation efficiencies, as well as pmoA (i.e., a methane-oxidizing enzyme) gene abundance in soils. Moreover, the potential methane emission of diesel-contaminated soil was relatively low when maize was introduced to the soil system. After microbial community analysis, various TPH-degrading microorganisms (Nocardioides, Marinobacter, Immitisolibacter, Acinetobacter, Kocuria, Mycobacterium, Pseudomonas, Alcanivorax) and methane-oxidizing microorganisms (Methylocapsa, Methylosarcina) were observed in the rhizosphere soil. The effects of major rhizoremediation factors on soil remediation efficiency and greenhouse gas emissions discussed herein are expected to contribute to the development of sustainable biological remediation technologies in response to global climate change.

• Korean Chemical Engineering Research
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• 제48권5호
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• pp.589-597
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• 2010

하수처리 시스템에서의 생물학적 영양염류 기준이 강화됨에 따라, 표준활성슬러지공법으로 운전 중인 하수처리장의 고도처리 공법으로의 개보수 필요성이 증가하고 있다. 그러나 실제 하수처리 시스템에서의 다양한 유입조건 및 운전조건의 복잡한 반응 구성으로 인해 실험을 통하여 개보수된 고도처리공법의 최적조건을 찾는 것은 쉽지 않은 일이며, 이는 많은 시간과 비용을 소모하여 비효율적이다. 따라서 본 연구에서는 활성슬러지공정모델(ASMs)을 기반으로 한 하수처리장의 모델링 및 시뮬레이션 기법을 통하여 하수처리장의 고도처리공법으로의 upgrading 설계를 수행하며, 이를 통계적이며 체계적으로 접근하기 위해 반응표면분석법(Response surface method)을 통한 고도처리공법의 설계 최적화를 수행하였다. 또한 실규모 하수처리장에서의 운전 최적화를 위해서는 하수처리의 동력학적 매개변수에 대한 정확한 분석이 수행되어야 한다. 본 연구에서는 다변량 통계분석 기법인 부분최소승자법(PLS)을 통하여 하수처리 시스템의 동력학적 매개변수 간의 상관관계를 파악하며, 고도처리공법 하수처리장의 운전 결과에 가장 큰 영향을 미치는 매개변수를 도출하였다. 본 연구를 통해 하수처리장의 고도처리공법 upgrading 설계 및 운전 최적화를 위한 방법론을 제시하였으며, 이를 통하여 설계시간 및 경비 절감 등 고도처리공법으로의 고효율적인 개보수가 가능할 것으로 예상된다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1610-1610
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• 2001

Microbiological examination of silage is of little value in gauging the outcome of silage, and so chemical analysis is more reliable and meaningful indicator of quality. On the other hand chemical assessments of the principal fermentation products provide an unequivocal basis on which to judge quality. Livestock require energy, protein, minerals and vitamins from their food. While fresh forages provide these essential items, conserved forages on the other hand may be deficient in one or more of them. The aim of the conservation process is to preserve as many of the original nutrients as possible, particularly energy and protein components (Woolford, 1984). Silage fermentation is important to preservation of forage with respect of feeding value and animal performance. Chemical and bacteriological changes in the silo during the fermentation process can affect adversely nutrient yield and quality (Moe and Carr, 1984). Many of the important chemical components of silage must be assayed in fresh or by extraction of the fresh material, since drying either by heat or lyophilisation, volatilises components such as acids or nitrogenous components, or effects conversion to other compounds (Abrams et al., 1987). Maize silage dorms the basis of winter rations for the vast majority of dairy and beef cattle production in Uruguay. Since nutrient intake, particularly energy, from forages is influenced by both voluntary dry matter intake and digestibility; there is a need for a rapid technique for predicting these parameters in farm advisory systems. Near Infrared Reflectance Spectroscopy (NIRS) is increasingly used as a rapid, accurate method of evaluating chemical constituents in cereals and dried forages. For many years NIRS was applied to assess chemical composition in dry materials (Norris et al., 1976, Flinn et al., 1992; Murray, 1993, De Boever et al., 1996, De la Roza et al., 1998). The objectives of this study were (1) to determine the potential of NIRS to assess the chemical composition of dried maize samples and (2) to attempt calibrations on undried samples either for farm advisory systems or for animal nutrition research purposes in Uruguay. NIRS were used to assess the chemical composition of whole - plant maize silage samples (Zea mays, L). A representative population of samples (n = 350) covering a wide distribution in chemical characteristics were used. Samples were scanned at 2 nm intervals over the wavelength range 400-2500 nm in a NIRS 6500 (NIRSystems, Silver Spring, MD, USA) in reflectance mode. Cross validation was used to avoid overfitting of the equations. The optimum calibrations were selected on the basis of minimizing the standard error of cross validation (SECV). The calibration statistics were R$^2$ 0. 86 (SECV: 11.4), 0.90 (SECV: 5.7), 0.90 (SECV: 16.9) for dry matter (DM), crude protein (CP), acid detergent fiber (ADF) in g kg$\^$-1/ on dry matter, respectively for maize silage samples. This work demonstrates the potential of NIRS to analyse whole - maize silage in a wide range of chemical characteristics for both advisory farm and nutritive evaluation.

• 생물환경조절학회지
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• 제17권2호
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• pp.170-175
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• 2008

오이 관비재배용으로 개발된 배양액의 적합성 여부를 판정하기 위해 관행 시비, 개발 관비용 배양액 및 Yamasaki 오이 배양액에 따른 토성의 화학성 변화, 생육 특성 및 과실 수량을 조사하였다. 잎의 광합성 및 증산율은 정식 48일째에는 개발 배양액 중 3/2배액과 Yamasaki오이 배양액 중 1/2 배액에서 높았으나 관행시비와 차이를 나타내지 않았다. 그러나 생육 후기에는 광합성은 개발 및 Yamasaki 오이 배양액 모두 3/2배액에서 높았고 관행시비와 큰 차이를 나타냈으나, 증산율은 개발 배양액의 3/2배액과 Yamasaki오이 배양액의 1/2과 1배액에서 높았고 관행시비와 차이를 나타내지 않았다. 그리고 오이 생장량과 과실수량은 관행시비보다 개발 배양액과 Yamasaki 오이 배양액에서 좋았고 두 배양액간에는 뚜렷한 차이를 나타내지 않았다. 잎의 무기성분도 Ca를 제외하고 유사한 경향이었다. 처리 전 토양과 비교하여 pH는 모든 배양액에서 낮아지고, EC는 다소 상승하는 경향이었고, P K, Ca 및 Mg의 축적 정도는 고농도로 급액할수록 큰 경향이었다. 따라서 개발된 배양액은 오이 관비재배용으로 적합한 것으로 생각된다.

• 한국초지조사료학회지
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• 제25권3호
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• pp.169-176
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• 2005

본 연구에서는 국내에서 반추가축용 조사료 원으로 많이 사용하고 있는 화본과 수입조사료 6종(bermuda grass hay, klein grass hay, oat hay, orchard grass straw, tall fescue straw and timothy hay)에 대하여 최근 NRC의 nutrient requirements of daily cattle(7th revised edition, 2001)에서 권장하는 사료의 영양성분 분석방법에 따라 일반조성분과 함께 heat-stable $\alpha-amylase$ treated neutral detergent fiber (aNDF), acid detergent fiber (ADF), acid detergent lignin(ADL), neutral detergent insoluble crude protein(NDICP)과 acid detergent insoluble crude protein(ADICP) 등의 함량을 분석하고 영양성분간의 Pearson의 상관계수를 산출하였다. 조사료에 따라 다소 차이는 있으나 oat hay는 CP와 NDICP(p<0.05), CP와 ADICP(p<0.01)의 상관관계가 높게 나타났고, orchard grass straw는 CP와 NDICP의 상관관계가 높게 나타났다(p<0.05). Tall fescue straw도 CP와 NDICP의 상관관계가 높게 나타났으며(p<0.01), timothy hay는 CP와 ADICP의 상관관계가 높게 나타났다(p<0.05). Klein grass hay는 CF와 aNDF (p<0.01), oat hay는 CF와 ADF(p<0.05), orchard grass straw는 CF와 ADL(p<0.05), tall fescue straw는 CF와 aNDF(p<0.01), CF와 ADF(p<0.01), timothy hay는 CF와 aNDF(p<0.01), CF와ADF(p<0.05), CF와 ADL(p<0.01)에서 높은 상관관계를 나타내었다. 이렇게 영양성분 간에 상관관계가 높은 성분들 간에는 앞으로 조사료의 영양성분에 영향을 미치는 제 요인들을 고정하여 상관관계를 조사하고, 분석점수를 많이 하여 회귀식을 만들 수 있다면 수입조사료 평가에 실질적인 적용이 가능할 것으로 생각된다.

• 에너지공학
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• 제29권3호
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• pp.34-41
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• 2020

Used disposable diapers have been considered for a long time as a type of waste difficult to recycle and valorize due to their composite nature including plastic, cellulose pulp, a super absorbent polymer and either urine, feces or both. Therefore, the fate of disposed diapers often is either incineration or landfill burial which both have various adverse environmental impacts. However, used disposable diapers contain nutrients: cellulose is an organic matter while urine and feces contain non negligible amounts of nitrogen, phosphorus and potassium which are primary nutrients included in most chemical fertilizers used in agriculture. In a scope of waste recycling and valorization, this study focuses on developing a method to achieve nutrient solution extraction from used disposable diapers. The experiment essentially consists in shredding the diapers and letting them macerate in solutions of sodium hydroxide with various concentrations to allow breaking down of the cellulose and super absorbent polymer and release of urine and feces before sterilizing the solutions in an autoclave to remove potential coliform bacteria. At the end of the experiment, a set of parameters is measured for the final solution to identify concentrations of nutrients as well as presence or absence of harmful substances. Results are discussed and directions for future studies are suggested, which include mechanization of the diapers shredding process or added aeration to enhance nitrification and absorption of extracted nutrients from plants.

• Asian-Australasian Journal of Animal Sciences
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• 제16권5호
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• pp.748-763
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• 2003

Anaerobic rumen microorganisms mainly bacteria, protozoa and fungi degrade ligno-cellulosic feeds consumed by the ruminants. The ruminants in developing countries are predominantly maintained on low grade roughage and grazing on degraded range land resulting in their poor nutrient utilization and productivity. Hence, manipulation of rumen fermentation was tried during last two decades to optimize ruminal fermentation for improving nutrient utilization and productivity of the animals. Modification of rumen microbial composition and their activity was attempted by using chemical additives those selectively effect rumen microbes, introduction of naturally occurring or genetically modified foreign microbes into the rumen and genetically manipulation of existing microbes in the rumen ecosystem. Accordingly, rumen protozoa were eliminated by defaunation for reducing ruminal methane production and increasing protein outflow in the intestine, resulting in improve growth and feed conversion efficiency of the animals. Further, Interspecies trans-inoculation of rumen microbes was also successfully used for annulment of dietary toxic factor. Additionally, probiotics of bacterial and yeast origin have been used in animal feeding to stabilize rumen fermentation, reduced incidence of diarrhoea and thus improving growth and feed conversion efficiency of young stalk. It is envisaged that genetic manipulation of rumen microorganisms has enormous research potential in developing countries. In view of feed resource availability more emphasis has to be given for manipulating rumen fermentation to increase cellulolytic activity for efficient utilization of low grade roughage.

• Journal of Ginseng Research
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• 제20권1호
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• pp.36-41
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• 1996

Chemical components of Panax (P) species were compared. p. species used were Korean white ginseng, Korean, Chinese and Japanese red ginseng (P ginseng), American and Canadian ginseng (P. quinquefolium) , and sanchl ginseng (P. notoginseng). No significant difference in the proximate contents was observed among P. species. Ash, crude lipld and total sugar contents in root of P. notoginseng were found to be relatively lower than those of P. ginseng and P. quinquefolium, but the contents of crude protein and crude fiber were similar among those ginsengs. Mineral nutrient con tents showed a little difference among ginseng species. Total nitrogen contents were slightly higher in P. ginseng than P. quinquefolium and P. notoginseng and Fe and Cu were lower in Chinese and Japanese red ginsengs. Kinds and compositions of amino acids were similar but contents of amino acids were different among ginseng species. Total amino acid contents were 76.3∼83.9 mg/g in P. ginseng 53.8∼60.4 mg/g in p. quinquefolium and 54.9 mg/g in P notoginseng. Free sugar contents were lower in P. notoginseng than P. ginseng or P. quinquefolium. Sucrose accounted for 90∼92% of total free sugar contents with relatively high content in white ginsengs, while sucrose and maltose were 32-36% and 55∼60%, respectively, in red ginseng.