• 한국축산시설환경학회지
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• 제4권2호
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• pp.167-174
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• 1998

It is known that the anaerobic fermentation of organic matter (OM) is divided into 2 phases, acidogenic phase in which OM is digested into volatile fatty acid (VFA), and methanogenic phase where the produced VFA is converted to CH4 and CO2. In a natural fermenting procedure, these 2 phases occur at the same time. However the total production of end products (methane) may be limited if these 2 phases occur at the same time. This is believed to be due to the difference in growth rate, substrate-utilizing efficiency and favorable environment for each microbes (acidogens and methanogens), involved in each phase. It is therefore suggested for the maximum recycling of organic waste (such as animal waste) through providing 2 different steps in fermenting procedure, acidogenic phase and methanogenic phase, in each case the activity of involved microbes can be maintained at the maximum level. The results obtained from these experiments are summarized as follows : The loading rates of swine waste were made through 2.5, 5 and 10 gVS / l / d to identify its acidogenic fermenting character in this study. The VFA yield was maximized at 10 gVS / l / d of loading rate. On the basis of this study was executed to identify the optimum HRT of 1, 2 and 4 days at 10 gVS / l / d of loading rate in acidogenic phase. The maximum VFA yield was obtained at 1 days of HRT.

• 생명과학회지
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• 제25권5호
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• pp.577-584
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• 2015

본 연구는 와송(둥근바위솔, Orostachys malocophyllus)에 대한 기초 연구의 일환으로 와송(OM)과 유산균 (Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus)으로 발효된 와송(FOM)의 건조 분말을 각각 정제수, 에탄올 및 메탄올로 추출하여 각각의 수율과 pH를 측정한 뒤, 총 페놀성 화합물과 이에 속하는 flavonoid 함량, 미네랄 함량을 측정하고 DPPH free radical scavenging 활성, Cu/Fe 환원력, 간 조직의 microsome 생체막의 지질과산화 억제능 및 linoleic acid를 이용한 지질과산화 정도를 비교 검토하였다. 총 페놀성 화합물과이에 속하는 대표적인 화합물인 flavonoid 함량은 와송의 정제수 추출물에서 가장 높은 함량을 나타내었고, 미네랄 함량은 K, Ca, Mg, Mn, Zn, Fe, Na의 순으로 높게 측정되었으며, 7원소 모두 발효 전에 비해 발효 후 함량이 증가하였다. DPPH를 이용한 radical 소거능을 측정한 결과, 와송과 발효와송의 에탄올 및 메탄올 추출물 0.5%에서 대조구인 합성항산화제 BHT 0.05%에 가까운 활성을 나타내었다. Fe와 Cu의 환원력은 모든 군에서 농도 의존적으로 증가하였고, 와송과 발효와송의 에탄올 및 메탄올 추출물 1%에서 대조구인 BHT 1%와 ascorbic acid 1%에 가까운 높은 환원력 을 나타내었다. 간 조직을 이용하여 측정한 지질과산화 억제활성은 모든 군에서 농도 의존적으로 증가하였고, 와송과 발효와송의 에탄올 추출물은 0.01%에서부터 BHT와 비슷한 활성 나타내었으며 1%에서는 BHT보다도 높은 활성을 나타내었다. TBA법과 thiocyanate법으로 지질과산화를 측정한 결과, 와송과 발효와송의 에탄올 및 메탄올 추출물 1%에서 지질과산화 억제능을 보였으며 발효와송의 메탄올 추출물은 두 가지 방법 모두에서 높은 지질과산화 억제능을 나타내었다. 따라서, 유산균 발효 와송은 천연 항산화제 소재로서 활용될 가능성이 보이며 이에 대한 심층적인 연구가 필요할 것으로 사료된다.

• 지질공학
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• 제10권2호
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• pp.150-171
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• 2000

제주도 해안지방에서 고염분 지하수가 산출되고 있다. 이 지역의 지질 구조에 의한 저지하수위 형성이 주 요인으로 보이며 부분적으로는 관정에서 과다양수 등의 사유가 문제가 된다. 본 연구에서는 고염분을 가진 관정의 분포를 알아내고, 16개의 전기전도도를 검층하였다. 동부지역에서 다른 지역에 비해 염소이온이 높게 나왔다. 관정저의 표고가 해수로 나누어 수질성분 분석자료를 비교하였다. 이외에 전기전도도를 검충하였다. 동부지역에서 다른 지역에 비해 염소이온이 높게 나왔다. 관정저의 표고가 해수면 기준 0m이상, 0m∼-10m, -10∼-20m, -20m∼-30m, -30m∼-40m, -40m 이하의 6개의 군으로 나누어 수질성분 분석자료를 비교하였다. 이외에 전기전도도 검층 등 다른 조사자료를 수집하여 염소이온과 관계를 파악하고, 염소이온도 분포도를 작성하였다. 북제주군 한림읍 지역에서 염수를 막은 2개의 사례는 염수 침입이 이루어지는 대수층을 그라우팅으로 붕쇄하여, 염수의 침입현상을 방지하는 공법이다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.43-43
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• 2017

During grain filling period, rice is affected by many environmental factors; including temperature, water, radiation and soil nutrition condition. In future climate, greater shading and heat tolerance will be required in rice. In this study, the effect of shading and high temperature on spikelet sterility was conducted on fourteen Vietnamese cultivars. Field experiments were studied in 2015 and 2016 to evaluate the response of Vietnamese cultivars under high temperature during grain filling stage. The high temperature and shading were applied by closing two sides of growth chamber and covered by a black cloth (50% reduced solar radiation) under the field condition after the first cultivar heading. The sterility increased significantly under high temperature and shading. The highest percentage sterile spiketlets was observed in 'Jasmine 85' (71.7%) under shading and in 'OM4900' (53.4%) under high temperature in 2015 and 2016, respectively. Among the treatments, the percentage of sterile spekelets in Vietnamese cultivars under shading was highest which was 54.9% and 41.8% in 2015 and 2016, respectively. Yield components reduced significantly in both of shading and high temperature. Corresponding with significantly decrease in yield components, the yield in high temperature and shading decreased strongly in both 2015 and 2016.

• Asian-Australasian Journal of Animal Sciences
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• 제11권2호
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• pp.145-151
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• 1998

The possibility of using rice gruel compared to that of the cane molasses as a source of readily fermentable energy for a urea supplemented straw diet has been studied. Twelve native growing bulls of $237{\pm}8.7kg $ live weight and months old were randomly allocated to three treatments fed solely rice straw enriched with : (1) 3% urea (US), (2) 3% urea + 15% molasses (UMS) and (3) 3% urea + 30% rice gruel (UGS). The feeding trial continued for sixty days. Organic matter (OM) intake was significantly (p < 0.05) higher in the UMS ( $64g/kg\;W^{0.75}/d$) followed by UGS ($53g/kg\;W^{0.75}/d$) and US ($49g/kg\;W^{0.75}/d$). Estimated (from digestible OM intake) metabolizable energy (ME) intake were 396, 348 and $301kJ/kg\;W^{0.75}/d$ for UMS, UGS and US respectively. The maintenance (i.e., no change in live weight) ME intake calculated to be $308{\pm}7.4kJ/kg\;W^{0.75}/d$. Urinary purine derivatives excretion was nonsignificantly higher in the UMS (51.73 mmol/d), followed by UGS (42.53 mmol/d) and US (35.26 mmol/d). The estimated microbial N (MN) yield were 21.10, 14.00 and 11.60 g/d for UMS, UGS and US respectively. For each MJ increase in ME intade, MN yield increased by $1.29{\pm}0.134g$. Observed live weight changes during the experimental period were 292, 125 and -19 g/d respectively for UMS, UGS and US. It was concluded that supplementation of readily fermentable N (urea) alone was not enough to optimize the rumen function and a source of readily fermentable energy was required. Rice gruel was less effective than molasses as fermentable energy source to remove a restriction on voluntary intake and provide less amino acids of microbial origin for absorption from the small intestine, Thus more substrate for protein synthesis and gluconeogenesis were available for growth in the molasses than the rice gruel supplemented animals. However, in situation where molasses is not available or costly, rice gruel does appear to have a place as readily fermentable energy source on a urea supplemented straw diet.

• 한국초지조사료학회지
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• 제21권4호
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• pp.191-202
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• 2001

Experiments were conducted on established grassland sward at Gongiam, Kwangju, and Kyung-gi in Korea from 1995 to 1997. The influence of mineral-N fertilizer or animal manure(AW) on herbage dry matter(DM) yield, N yield, the recovery of AM-N, and soil N and organic matter(0M) content in the mixed sward('potomac' orchardgrass, 'fawn' tall fescue, and 'kenblue' Kentuky bluegrass) was investigated. The treatments were replicated three times in a split plot block design. AM(the main plots) was applied at 200kg N ha ' year ' on each plot. The types of AM were cattle feedlot manure(CFM), pig manure fermented with sawdust(PMFS) and Korea native cattle slurry(KNCS). Three levels of mineral-N fertilizer, as urea, ranging from 0 to 200kg N $ha^{-1}\;year^{-1}$ in 100kg increments, were superimposed on each plot. The fertilizers and AM were applied in two equal dressings(the end of March and middle of November). AM and mineral fertilizer had significant effects(p<0.05) on herbage DM and N yields. Herbage yields in KNCS were higher than those in CFM and PMFS(p

• 한국초지조사료학회지
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• 제20권3호
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• pp.221-226
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• 2000

Cassia mimosoides var. nomame was grown at five seeding rates (10, 20, 30, 40 and 50 kg/ha) from March 31 to September 21, 1998 at Cheju to determine influence of seeding rate on agronomic characters, and forage yield and quality. Days to flowering increased from 126 to 129 days as seeding rate increased from 10 to 50 kg/ha. The plant height increased from 86 to 99 cm as seeding rate was increased from 10 to 30 kg/hac and then decreased to 93 cm at a rate of 50 kglha. With increasing seeding rate, stem diameter quadratically decreased and the number of branches and green leaves per plant linearly decreased but the number of withering leaves per plant linearly increased. As seeding rate increased &om 10 to 30 kg/ha, fresh forage, dry matter, crude protein, and total digestible nutrients (TDN) yield increased 'from 30.7 to 49.1, 7.5 to 12.2, 0.90 to 1.57 and 4.09 to 7.09 MTha, respectively, and then decreased with further increased seeding rates. Crude protein, ether extract, nitrogen free extract, and TDN wntent increased 12.1 to 14.2% 2.2 to 2.9%, 35.1 to 39.2%, 54.8 to 60.3% respectively, but crude fiber wntent decreased 39.8 .to 33.3% and crude ash declined 4.9 to 3.8% as seeding rate increased from 10 to 50 kgiha. The optimum seeding rate to obtain the highest TDN yield was estimated to be 36kglha. (Key words : Cassia mimosoides var. nomame, Seeding rate, Forage yield, Forage quality)

• 한국토양비료학회지
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• 제50권3호
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• pp.187-194
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• 2017

This study was conducted to investigate rice yield and soil chemical properties affected by incorporation levels of green barley (GB) and hairy vetch (HV). The GB and HV were applied to the pots at 500, 1,000, 1,500, and $2,000kg\;10^{-1}$ (GB500, GB1000, GB1500, GB2000, HV500, HV1000, HV1500, and HV2000, respectively), and inorganic fertilizer ($N-P-K=9-4.5-5.7kg\;10a^{-1}$) treatment as control. After rice harvesting, chemical properties of soil such as pH, OM, T-N, and available $P_2O_5$ in GB and HV treated treatments were improved over those in Control treatment. The rice yield ranged from 433 to $512kg\;10a^{-1}$ for GB treatments and 490 to $532kg\;10a^{-1}$ for HV treatments, indicating that rice yield was affected by incorporation levels of GB and HV. The rice yields in GB2000, HV1000, HV1500 and HV2000 treatments increased by 3.3, 3.1, 6.4 and 7.4% compared with Control treatment, respectively. Therefore, minimum incorporation level of GB and HV for increasing rice yield was $2,000kg\;10a^{-1}$ of GB and $1,000kg\;10a^{-1}$ of HV.

• Asian-Australasian Journal of Animal Sciences
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• 제19권8호
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• pp.1159-1163
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• 2006

This experiment was performed to examine the influences of high ambient temperature on milk production, nutrient digestibility, energy and protein sufficiency ratio, and plasma metabolites concentration in lactating cows. In a $2{\times}2$ crossover design, four multiparous lactating Holstein cows were maintained in a chamber under treatment of constant moderate ($18^{\circ}C$) ambient temperature (MT) or high ($28^{\circ}C$) ambient temperatures (HT). The DMI and milk protein yield were significantly lower in HT (p<0.05). The milk yield, milk lactose yield, and milk SNF yield tended to be lower in HT (p<0.10). No statistical differences for 4% fat-corrected milk and milk fat yield were observed. Rectal temperatures were significantly higher in HT than MT (p<0.05). The apparent DM, OM, ether extract, CF, and ash digestibility did not differ between treatments. On the other hand, the apparent CP digestibility was increased significantly (p<0.05) and nitrogen free extract tended to increase (p<0.10) in HT. The sufficiency ratio of ME and DCP intake for each requirement tended to be lower in HT than in MT (p<0.10). Concentrations of total protein (TP), albumin, and urea nitrogen in plasma did not differ between treatments. Plasma 3-methylhistidine (3MH) concentration as a marker of myofibrillar protein degradation tended to be higher in HT (p<0.15). In conclusion, high ambient temperature was associated with a lower energy and protein sufficiency ratio, and decreased milk protein production, even though the body protein mobilization tended to be higher.

• 한국작물학회지
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• 제50권4호
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• pp.247-255
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• 2005

ice yield and plant growth response to nitrogen (N) fertilizer may vary within a field, probably due to spatially variable soil conditions. An experiment designed for studying the response of rice yield to different rates of N in combination with variable soil conditions was carried out at a field where spatial variation in soil properties, plant growth, and yield across the field was documented from our previous studies for two years. The field with area of 6,600 m2 was divided into six strips running east-west so that variable soil conditions could be included in each strip. Each strip was subjected to different N application level (six levels from 0 to 165kg/ha), and schematically divided into 12 grids $(10m \times10m\;for\;each\;grid)$ for sampling and measurement of plant growth and rice grain yield. Most of plant growth parameters and rice yield showed high variations even at the same N fertilizer level due to the spatially variable soil condition. However, the maximum plant growth and yield response to N fertilizer rate that was analyzed using boundary line analysis followed the Mitcherlich equation (negative exponential function), approaching a maximum value with increasing N fertilizer rate. Assuming the obtainable maximum rice yield is constrained by a limiting soil property, the following model to predict rice grain yield was obtained: $Y=10765{1-0.4704^*EXP(-0.0117^*FN)}^*MIN(I-{clay},\;I_{om},\;I_{cec},\;I_{TN},\; I_{Si})$ where FN is N fertilizer rate (kg/ha), I is index for subscripted soil properties, and MIN is an operator for selecting the minimum value. The observed and predicted yield was well fitted to 1:1 line (Y=X) with determination coefficient of 0.564. As this result was obtained in a very limited condition and did not explain the yield variability so high, this result may not be applied to practical N management. However, this approach has potential for quantifying the grain yield response to N fertilizer rate under variable soil conditions and formulating the site-specific N prescription for the management of spatial yield variability in a field if sufficient data set is acquired for boundary line analysis.