• Asian-Australasian Journal of Animal Sciences
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• 제22권12호
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• pp.1676-1685
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• 2009

This trial was conducted to determine the effects of various feed additives on nutrient digestibility, performance and carcass traits of growing-finishing pigs fed diets containing wheat distiller' grains with solubles (WDGS). Seventy-two, individually fed pigs (19.7${\pm}$2.6 kg), were assigned to one of six dietary treatments in a 6${\times}$2 (treatment${\times}$sex) factorial design (N = 12). The control diet was based on wheat and soybean meal while the five experimental diets contained 20% WDGS during the growing period and 12% WDGS during the finishing period. One 20% WDGS diet was unsupplemented while the remaining diets were supplemented with either 0.1% threonine, 5% canola oil, 0.2% enzyme (0.1% Endofeed W containing 1,250 units/g of xylanase and 385 units/g of $\beta$-glucanase and 0.1% Vegpro containing 7,700 HUT/g protease and 75 CMC/g cellulase), or a combination of the three additives at the same levels as those fed separately. The digestibility of dry matter, crude protein and energy were all significantly higher in the control diet than the unsupplemented diet containing 20% WDGS. None of the feed additives improved nutrient digestibility. In addition, none of the additives had any significant effect on gain or feed intake during the growing (19.7 to 43.6) or finishing (43.6 to 114.3 kg) periods or overall (19.7 to 114.3 kg). During the growing period, feed conversion was significantly improved for pigs fed the combination of additives compared with the unsupplemented WDGS diet. During the finishing period and overall, feed conversion was significantly improved for pigs fed 5% canola oil alone or in combination with the other additives. None of the supplements had any effect on carcass traits. These results indicate that WDGS can be successfully used as a partial replacement for soybean meal in diets fed to growingfinishing pigs. However, due to its low energy content, there may be some merit in including high energy ingredients such as canola oil when diets containing WDGS are fed.

• 한국균학회지
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• 제21권4호
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• pp.285-292
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• 1993

에너지 요구 반응 인 5'-XMP 의 5'-GMP 보의 효소적 전환을 위해 Escherichia coli CH 41(guaB mutant)로부터 추출 정제한 XMP aminase에 Saccharomyces cerevisiae의 glycolysis를 통한 ATP 재생계를 도입하였다. 전환 반응의 ATP원으로는 동결 건조 효모가 가장 효율적이었으며, 전환 반응의 최적 온도 및 pH는 각각 $40{\circ]C$, pH 7.4였다. 또한 100 mM glucose, 100 mM inorganic phosphate 및 6mM AMP 에서 가상 높은 전환율을 보였다. 상기의 조건에서 36 unit/ml의 XMP aminase 가 이용될 경우 효모 농도는 60 mg/ml로 충분하였으며, 최적 조건에서 6시간 반응시 1.8 mM(65.6 mg/100 ml) 5'- XMP 의 약 71%가 5'-GMP로 전환되었다.

• 전기화학회지
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• 제22권1호
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• pp.22-35
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• 2019

이차 전지의 개발이 전기자동차나 스마트그리드와 같은 중대형의 에너지저장장치로 응용범위가 확대됨에 따라 이차 전지의 경제성확보가 화두가 되고 있다. 나트륨이차전지는 리튬보다 훨씬 저렴한 나트륨원료를 사용하여 저가의 차세대 이차 전지로 크게 주목받고 있다. 이에 따라 이온 반경이 큰 나트륨이온의 삽입과 탈리를 원활하게 해줄 수 있는 음극 소재의 개발이 최근 몇 년간 활발히 수행되어 왔다. 나트륨이차전지용 음극은 세 가지의 반응 메커니즘 (층간 삽입반응, 금속-합금반응, 전환반응)을 기반한 소재들이 보고되었으며, 본 총설에서는 전환반응으로 구동하는 다양한 음극 소재들을 소개하며 나트륨 전지 셀 내 반응 메커니즘을 소개하고자 한다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권6호
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• pp.1020-1033
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• 2015

In order to design a compact urea selective catalytic reduction system, numerical simulation was conducted by computational fluid dynamics tool. A swirl type static mixer and a mixing chamber were considered as mixing units in the system. It had great influence on flow characteristics and urea decomposition into ammonia. The mixer caused flow recirculation and high level of turbulence intensity, and the chamber increased residence time of urea-water-solution injected. Because of those effects, reaction rates of urea decomposition were enhanced in the region. When those mixing units were combined, it showed the maximum because the recirculation zone was significantly developed. $NH_3$ conversion was maximized in the zone due to widely distributed turbulence intensity and high value of uniformity index. It caused improvement of $NO_x$ reduction efficiency of the system. It was possible to reduce 55% length of the chamber and connecting pipe without decrease of $NO_x$ reduction efficiency.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.1029-1036
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• 2012

Push-pull-type copolymers - low-band-gap copolymers of electron-rich fused-ring units (such as cyclopentadithiophene; CPDT) and electron-deficient units (such as benzothiadiazole; BT) - are promising donor materials for organic solar cells. Following a design principles proposed in our previous study, we investigate the electronic structure of a series of new CPDTBT derivatives with various electron-withdrawing groups using the time-dependent density functional theory and predict their power conversion efficiency from a newlydeveloped protocol using the Scharber diagram. Significantly improved efficiencies are expected for derivatives with carbonyl [C=O], carbonothioyl [C=S], dicyano [$C(CN)_2$] and dicyanomethylene [C=$C(CN)_2$] groups, but these polymers with no long alkyl side chain attached to them are likely to be insoluble in most organic solvents and inapplicable to low-cost solution processes. We thus devise several approaches to attach alkyl side chains to these polymers while keeping their high efficiencies.

• KIEAE Journal
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• 제16권2호
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• pp.11-16
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• 2016

Purpose: International efforts to save Earth's environment against global warming and environmental pollution have been made in many countries. Energy consumption of buildings has been continuously increasing, and it has been over 40% of total energy consumption in the world. Energy consumption of buildings in Korea reaches 24% of total energy consumption. So, Korea government has executed building energy rating systems to control energy consumption of buildings. Method: This study was carried out to evaluate the energy performance of apartment unit plans according to converting balconies into living areas. For the study, six types of input models were made. Two input models(SP1 and SP 2) were the standard units that balcony areas were not converted into living areas, and four ones(EP 1, EP 2, EP 3 and EP 4) were the extended unit plans that balcony areas were turned into living areas. All of them were simulated with ECO2 software to assess building energy efficiency. Result: According to the results, the energy performance of the EP 2 and EP 4 models were 21. 8% higher than SP 1 model and 9.2% higher than SP 2 model.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.567-570
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• 2000

DFA IV를 생산하는 levan fructotransferase를 ${\kappa}\;-carrageenan$을 이용하여 고정화한 결과 카라기난의 농도가 2%일 때 가장 높은 활성을 나타내었다. 이 때에 고정화 담체에 포괄되어지는 효소의 활성도는 0.81 units으로서 soluble enzyme 7.7 units에 비해 상대적으로 낮은 활성을 보여주었다. 고정화 및 soluble enzyme의 최고 활성온도와 최적 pH는 동일하게 $55^{\circ}C$, pH6.0 이었다. 가교제를 처리할 경우에 적당한 농도는 0.5%로 생각되어진다. $37^{\circ}C$에서 시간에 따른 고정화 및 soluble enzyme의 DFA IV 생산량을 HPLC로 분석한 결과 60시간 이후의 전환률이 각각 32%, 61%로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제8권1호
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• pp.59-66
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• 1995

Energy obtained by grazing cattle in oil palm plantations is usually used for maintenance of body functions, the construction of body tissues and pregnancy, the synthesis of milk and the conversion to mechanical energy used for activities such as walking, eating and others. In this study, attempt was made to estimate metabolizable energy (ME) requirement of grazing cattle. Models of ME requirement (MER) for maintenance, gain, pregnancy, lactation and activities were developed. ME system and units were used because of wide recognition. Estimation of ME intake in grazing cattle was expressed as MEVI = $14.58{\times}VI{\times}DMD$, and under grazing condition MEVI = $MER_i$. MER was expressed as a function of net energy(NER, MJ) required for the i'th body function. Coefficient of efficiency for conversion of ME into net energy(ki) was adopted from literatures. Quantifying of ME requirement for Kedah-Kelantan cattle under grazing condition was made by using equation MERM = NEM / kn. The estimated values of MER for Kedah-Kelantan cattle is quite reasonable if compared with other estimates as reported in literatures from stall-fed animals. Dynamic MER models for grazing herd was developed in order to estimate ME requirement for maintenance and productions. These ME requirement models can be used for prediction of energy utilization pattern of the herd in the grazing systems.

• Journal of Microbiology and Biotechnology
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• 제16권11호
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• pp.1678-1683
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• 2006

A novel suspension-phase enzyme reaction system for the intermolecular transglycosylation of L-ascorbic acid into 2-O-${\alpha}$-D-glucopyranosyl L-ascorbic acid supplementing extrusion starch as the glycosyl donor was developed using cyclodextrin glucanotransferase from Thermoanaerobacter sp. A high conversion yield compared to the conventional soluble-phase enzyme reaction system using cyclodextrins and soluble starch was achieved. The optimal reaction conditions were 2,000 units of cycIodextrin glucanotransferase, 20 g/l of L-ascorbic acid, and 50 g/l of extrusion starch at $50^{\circ}C$ for 24 h. The new suspension-phase enzyme reaction system also exhibited several distinct advantages other than a high conversion yield, including a lower accumulation of oligosaccharides and easily separable residual extrusion starch by centrifugation or filtration in the reaction mixture, which will facilitate the purification of 2-O-${\alpha}$-D-glucopyranosyl L-ascorbic acid. The new suspension-phase enzyme reaction system seems to be potentially applicable as the industrial process for the production of thermally and oxidatively stable 2-O-${\alpha}$-D-glucopyranosyl L-ascorbic acid.

• 한국전기전자재료학회논문지
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• 제31권1호
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• pp.34-39
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• 2018

In this study, e-beam equipment was used to form silver nanoparticles on thin films of $TiO_2$ to increase the efficiency of dye-sensitized solar cells and improve the annealing process. $TiO_2$ thin films with nanoparticle photoelectrodes were fabricated in individual units for use in dye-sensitized solar cells. The characteristics of dye-sensitized solar cells were compared to those of the prepared $TiO_2$ photoelectrode with and without nanoparticles. The dye-sensitized solar cells with silver nanoparticles showed a significant increase in the electric current density compared with the pure $TiO_2$ dye-sensitized solar cell and improved the solar conversion efficiency to 27.89%. The increased density of electric current increased the extent of light absorption of the dye owing to the plasmon resonance of the nanoparticles at the local surfaces. This phenomenon led to increased light scattering, which in turn increased the current density of the dye-sensitized solar cells and improved the solar conversion efficiency.