• 청정기술
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• 제16권2호
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• pp.103-116
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• 2010

평면 판넬 디스플레이(FPD)산업 중 액정표시장치(LCD) panel 시장은 계속 성장하고 있으며, 대형화와 생산은 해마다 증가하고 생산기술은 향상되고 있다. FPD의 제조공정은 고도의 청정성이 요구되는 공정으로 제조공정 중 세정공정이 30~40%를 차지할 정도로 기술적 생산성 측면에서 매우 중요하다. 그 중 액정주입 후 잔류하는 액정은 미세갭에 잔류하여 제거하기 매우 어렵다. 본 연구에서는 대체세정제의 원료로 많이 이용되고 있는 glycol ether계 용제, glycol dimethyl ether계 용제, 그리고 비이온계면활성제를 사용하여 우수한 세정력, 린스력, 침투력을 갖고 배선에 영향을 주는 이온함량을 최소화한 수계세정제를 개발하여 액정주입 후에 사용되는 panel의 액정 세척에 적용해 보았다. 이에 따라 배합성분들의 혼합비에 따른 세정제의 물성, 세정 효율 및 헹굼성을 측정하여 보았다. 실험 결과에 따르면, 배합세정제는 기존의 세정제보다 높은 습윤지수와 높은 운점을 보였다. 그리고 세정제의 주용제의 구조변화와 오염물로서 액정의 종류에 따라 세정효율이 영향을 미치고 있음이 확인되었다. 또한 최적의 배합세정제는 기존의 세정제에 비하여 동등이상의 세정력을 보여주었고 헹굼성능도 훨씬 우수하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권1호
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• pp.41-44
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• 2007

The callipyge mutation in sheep is a polar overdominant mutation that results in post-natal muscle hypertrophy in the loin and hindquarters of paternal heterozygotes (+/CLPG). Sheep that are homozygous for the callipyge allele (CLPG/CLPG) do not express the muscle hypertrophy phenotype, but serve as carriers for the mutation. Callipyge sheep are characterized by improved feed efficiencies and leaner carcasses. Leptin is a protein hormone secreted from adipose tissue and has been found to affect appetite and serve as an indicator of body fat mass. To date, very little knowledge is available as to the effect of the callipyge mutation on circulating leptin levels. Due to the interaction of leptin with feed intake and energy availability, and the fact that the majority of fetal growth occurs in late gestation, it is important to understand if the callipyge mutation interacts with leptin production in late gestational ewes. Therefore, our objective was to characterize serum concentrations of leptin in late gestational callipyge ewes vs. non-callipyge ewes. We evaluated genetically verified callipyge (n=6), homozygous (n=8) and normal (n=8) ewes weekly during the last eight wks of gestation through one wk post-partum. Weights were taken and body condition scores were assigned by trained personnel weekly. Blood was collected via jugular venipuncture on each sampling date and subjected to an ovine-specific leptin RIA. Genotype influences on peripheral concentrations of leptin were found to be highly significant (p=0.0005). Total leptin means for +/CLPG were 5.41${\pm}$0.40 ng/ml, CLPG/CLPG 8.11${\pm}$0.70 ng/ml, and +/+ 9.13${\pm}$0.93 ng/ml. Sampling date was also significant (p=0.0098) with all ewes showing a decrease in leptin levels throughout gestation and parturition. Using repeated measures, we were able to detect lower levels of plasma leptin in callipyge ewes, which may be indicative of their lower overall body fat content. These results indicate that the callipyge phenotype decreases the levels of adipose tissue and leptin production in gestating ewes.

• 대한방사성의약품학회지
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• 제2권2호
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• pp.84-95
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• 2016

Considerably increasing interest in using the theranostic isotopes/ isotope pairs of radiometals like $^{44/47}Sc$ and $^{64/67}Cu$ for diagnosis and/or therapeutic applications in the nuclear medicine procedures necessitates its reliable production and supply. Separation and purification of no-carrier-added (NCA) isotopes from macro quantitates of the irradiated target matrix along with other impurities is a cardinal procedure amongst several other steps involved in its production. Multitudinous methods including but not limited to liquid-liquid (solvent) extraction, extraction chromatography (EXC), ion exchange, electrodeposition and sublimation are routinely applied either solitarily or in combination for the separation and purification of radioisotopes depending on their production routes, radioisotope of interest and impurities involved. However, application of EXC though has shown promises towards the numerous separation techniques have not received much attention as far as its application prospects in the field of nuclear medicine are concerned. Advances in the recent past for application of the EXC resins in separation and purification of the several medically important radioisotopes at ultra-high purity have shown promising behavior with respect to their operation simplicity, acidic and radiolytic stability, separation efficiencies and speedy procedures with the enhanced and excellent extraction abilities. In this mini review we will be talking about the recent developments in the application and the use of EXC techniques for the separation and purification of $^{44/47}Sc$ and $^{64/67}Cu$ for medical applications. Furthermore, we will also discuss the scientific and practical aspects of EXC in the view of separation of the NCA trace amount of radionuclides.

• Asian-Australasian Journal of Animal Sciences
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• 제30권5호
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• pp.660-665
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• 2017

Objective: The objective of the study was to determine the effects of increasing levels of metabolizable protein (MP) on lactation performance and nitrogen (N) efficiencies in lactating dairy cows. Methods: Nine multiparous cows in mid lactation [$113{\pm}25$ days in milk] received three treatments in a $3{\times}3$ Latin square design with a period length of 21 days. The treatments were three diets, designed to provide similar energy and increasing supply of MP (g/d) (2,371 [low], 2,561 [medium], and 2,711 [high] with corresponding crude protein levels [%]) 15.2, 18.4, and 20.9, respectively. Results: Increasing MP supplies did not modify dry matter intake, however, it increased milk protein, fat, and lactose yield linearly. Similarly, fat corrected milk increased linearly (9.3%) due to an increase in both milk yield (5.2%) and milk fat content (7.8%). No effects were observed on milk protein and lactose contents across the treatments. Milk nitrogen efficiency (MNE) decreased from 0.26 to 0.20; whereas, the metabolic efficiency of MP decreased from 0.70 to 0.60 in low to high MP supplies, respectively. The concentration of blood urea nitrogen (BUN) increased linearly in response to increasing MP supplies. Conclusion: Increasing MP supplies resulted in increased milk protein yield; however, a higher BUN and low MNE indicated an efficient utilization of dietary protein at low MP supplies.

• Asian-Australasian Journal of Animal Sciences
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• 제15권5호
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• pp.658-664
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• 2002

This study was conducted to determine a proper feeding regime for lactating Holstein cows during the warm season in Taiwan. In Feeding Trial, 21 lactating Holstein cows were randomly allotted into three feeding regimes in a Completely Randomized Design. The feeding regimes were roughage fed ad libitum along with concentrate fed either twice daily (2C) or four times daily (4C), and total mixed ration (TMR) for 8 weeks. No significant differences among the three feeding regimes were found in body weight changes, and intakes in terms of dry matter, crude protein and net energy. For milk yield and 4% FCM yield, 4C were higher than the other two feeding regimes (p<0.05). No significant differences were found in milk compositions or differences noted in the yields of the respective milk components. TMR was worse than 2C and 4C (p<0.05) in milk production efficiencies in terms of dry matter intake per kg milk yield, crude protein intake per kg milk protein yield, as well as dry matter intake, net energy intake and crude protein intake per kg 4% FCM yield. Three ruminally fistulated Holstein dry cows were randomly assigned into the same three feeding regimes in a 3${\times}$3 Latin Square Design. No significant differences were found among the feeding regimes in ruminal pH, ammonia nitrogen, total VFA concentration, molar percentages of VFA, and acetic acid: propionic acid ratio (C$_2$/C$_3$). Taken all together, roughage fed ad libitum and concentrate fed four times daily was the better feeding regime for lactating cows during the warm season in Taiwan.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.737-743
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• 1999

A conventional thermophilic anaerobic digester was converted into a thermophilic high-rate hybrid anaerobic reactor (THAR) for treating distillery wastewater. The THAR has been operating successfully since May 1995 at a loading rate of 5.45 to $11.52{\;}kg/\textrm{m}^3/d$ (maximum of 15.02). The THAR has demonstrated a soluble Chemical Oxygen Demand (sCOD) removal efficiency of 85 to 91% and a total COD (tCOD) removal efficiency of as much as 72 to 84%. Product gas had a methane content of 59 to 68%. The tCOD removal rates were 4.31 to 5.43, 6.26 to 6.89, and 9.03 to $9.78kg{\;}tCOD/\textrm{m}^3/d$ for tapioca, com, and naked-barley wastewater, respectively. The sCOD removal rates ranged from 3.75 to 4.79,3.28 to 4.89, and 5.57 to 6.21kg $sCOD/\textrm{m}^3/d$ for tapioca, com, and naked-barley wastewater, respectively. There were unknown substances in a naked-barley distillery wastewater that were identified as being toxic for microorganisms. However, the THAR treated naked-barley wastewater continuously for 26 days, operating at an average tCOD loading of $11.08{\;}kg/\textrm{m}^3/d$without any signs of deterioration in either COD removal efficiency or gas production rate. During this period, the average removal efficiencies of tCOD and sCOD were 84% and 91%, respectively, and the gas production rate averaged 6.61 to $7.57{\;}\textrm{m}^3/\textrm{m}^3$ reactor/d which produced 0.57 to $0.69{\;}\textrm{m}^3{\;}biogas/kg{\;}tCOD_{rem}$. From tapioca and com wastewater, the reactor showed an average gas production rate of 3.18 to 3.46 and 4.91 to $5.22{\;}\textrm{m}^3/\textrm{m}^3$ reactor/d which produced 0.53 to 0.69 and 0.62 to $0.71{\;}\textrm{m}^3/kg{\;}tCOD_{rem}$, respectively.

• 자원ㆍ환경경제연구
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• 제20권1호
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• pp.33-60
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• 2011

본 연구의 목적은 생산 프론티어 접근을 통하여 OECD 국가의 에너지효율과 경제성장이 에너지수요에 미치는 영향을 비교하는 것이다. 본 연구는 OECD 국가를 대상으로 전통적 에너지 원단위와 생산 프론티어 접근에 의한 에너지효율, 생산 프론티어 상의 효율점에서 에너지 과다 여유분의 존재, 생산의 기술구조 하에서 GDP 증가에 따른 에너지수요 탄력성을 살펴보았다. 첫째, 전통적 에너지 원단위는 방사선 에너지효율과는 상관성이 낮고 여유분 에너지효율, 비방사선 에너지효율과 에너지 최소화 방향의 수평선 에너지효율 등과는 일정한 상관성을 보인다. 에너지 원단위만으로 에너지효율 여부를 판단하는 것은 오류가 있을 수 있다. 특히 방사선 효율에 의한 에너지효율은 대부분의 국가의 에너지효율을 과대평가하는 경향이 있다. 둘째, OECD 국가들이 프론티어 상의 효율적인 생산점에서도 불필요하게 에너지를 소비하는 것이 연평균 17.3%이므로 에너지의 추가 저감이 필요하다. 셋째, OECD 국가의 경제성장에 대한 에너지 탄력성의 평균은 1.1로서 거의 단위 탄력성에 가깝다. 탄력성의 국가별 차이는 존재하고 탄력성이 높은 국가의 에너지수요는 높다.

• 펄프종이기술
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• 제45권2호
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• pp.46-55
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• 2013

Recently, there are growing interests on carbon emissions related in climate change which is worldwide emerging important issue. Some research works are now carrying out in order to reduce the carbon emission in pulp and paper industries by the synthesis of precipitated calcium carbonate using the exhaust carbon dioxide from combustion furnace or incinerator. However, for solving the original problems on carbon emission, we need to consider the analysis of basic methodology on $CO_2$ through the process efficiencies. There are two general tools for carbon emissions; one is the greenhouse gas inventory and the other is $LCCO_2$ method which is applied to particular items of raw materials and utilities in unit process. In this study, the carbon emissions in wood-containing printing paper production line were calculated by using $LCCO_2$ method. The general materials and utilities for paper production, such as fibrous materials, chemical additives, electric power, steam, and industrial water were analyzed. As the results, $Na_2SiO_3$ showed the highest loads in carbon emissions, and the total amount of carbon emissions was the highest in electricity. In the production line of printing paper using de-inked pulp and BTMP, as the mixing ratio of DIP was higher, the carbon emissions were decreased because of high use of electric power in TMP process.

• Journal of Microbiology and Biotechnology
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• 제23권1호
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• pp.92-98
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• 2013

Microalgal cultivation using wastewater is now regarded as essential for biodiesel production, as two goals can be achieved simultaneously; that is, nutrient removal efficiency and biomass production. Therefore, this study examined the effects of carbon sources, the N:P ratio, and the hydraulic retention time (HRT) to identify the optimal conditions for nutrient removal efficiency and biomass production. The effluent from a 2nd lagoon was used to cultivate microalgae. Whereas the algal species diversity and lipid content increased with a longer HRT, the algal biomass productivity decreased. Different carbon sources also affected the algal species composition. Diatoms were dominant with an increased pH when bicarbonate was supplied. However, 2% $CO_2$ gas led to a lower pH and the dominance of filamentous green algae with a much lower biomass productivity. Among the experiments, the highest chlorophyll-a concentration and lipid productivity were obtained with the addition of phosphate up to 0.5 mg/l P, since phosphorus was in short supply compared with nitrogen. The N and P removal efficiencies were also higher with a balanced N:P ratio, based on the addition of phosphate. Thus, optimizing the N:P ratio for the dominant algae could be critical in attaining higher algal growth, lipid productivity, and nutrient removal efficiency.

• 한국환경과학회지
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• 제31권7호
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• pp.609-616
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• 2022

In this study, the effect of different reaction times for thermal-alkaline pretreatment on the solubilization and biogasification of polyhydroxybutyrate (PHB) were evaluated. Thermal-alkaline pretreatment tests were performed at 73 ℃ and pH 13 at 0-120 h reaction times. The mesophilic anaerobic batch tests were performed with untreated and pretreated PHB samples. The increase in the pretreatment reaction time results in a 52.8-98.8% increase of the abiotic solubilization efficiency of the PHB samples. The reaction time required to achieve solubilization efficiencies of 50%, 90%, and 95% were 10.5, 52.0, and 89.6 h, respectively. The biogasification of the untreated PHB samples achieved a specific methane production rate of 3.6 mL CH₄/g VSS/d and require 101.3 d for complete biogasification. The thermal-alkaline pretreatment significantly improved specific methane production rate (10.2-16.0 time increase), lag time (shortened by 76-81%), and time for complete biogasification (shortened by 21-83%) for the biogasification of the PHB samples when compared to those of the untreated PHB samples. The improvement was higher as the reaction time of the thermal-alkaline pretreatment increased. The findings of this study could be used as a valuable reference for the optimization of the biogasification process in the treatment of PHB wastes.