• 한국자원식물학회지
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• 제18권1호
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• pp.169-178
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• 2005

중이온빔$(^{20}Ne)$을 담배 식물체에 조사(irradiation)하여 식물체의 생장과 DNA의 변이에 미치는 영향을 검토하였다. 발아율과 초장은 조사선 량이 증가함에 따라 감소하였다. 반면 $50Gy\~10Gy$의 저선량에서 추대와 개화가 촉진되어 발육은 오히려 촉진되었다. 총 100개의 primer를 이용하여 RAPD분석한 결과, 59개의 primer에서 총 336개의 DNA단편이 증폭되었고, 1개의 primer에서 중이온빔 조사처리구에서만 출현하는 DNA단편이 나타났다. AFLP분석 결과, 개체 특이적인 DNA단편은 나타난 반면 중이온빔 처리구 특이적인 DNA 단편은 관찰되지 않았다.

• 보존과학연구
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• 통권23호
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• pp.41-57
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• 2002

It has been proved that pollutants stuck on the surface of stone architecture have significant direct and indirect harmful effects on them. Among them some do not look evidently harmful, but they have potentials to ruin stone architecture as time goes on. Since the cultural assets have magnificent meanings as historical aspects, their future states should be considered seriously as well as that of the presence. The past method to get rid of the pollutants from the surface of cultural properties has been changed a lot till the present along with scientific development of technology on this field. Existing method to eliminating pollutants are based on physical and chemical processing, which can make damages on them too. Recently cleansing using LASER has been developed in Europe and proved as effective and relatively less harmful to remove pollutants, and it has been adopted widely. After the success of the way by LASER, there are several trials to adopt the way to our cultural properties which have similar materials. Those showed satisfactory results and studies for developing the securer and more dependable ways to apply. From now on the report will show the effective ways to apply the method using LASER on to the similar materials and different materials as well and discuss about the pros and cons about the method.

• 한국토양비료학회지
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• 제48권4호
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• pp.285-294
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• 2015

Ordination has been recognized useful method to analyze the effects of multiple environmental factors on dozens of species in vegetation ecology because of summarizing community data by producing a low-dimensional graphics. Main objective of this study was the application of ordination method, especially principal components analysis (PCA), to analyze the soil characterization on paddy treated by different green manure crops and tillage methods. Treatments included the three tillage treatments and two green manure crops as the following; (i) moldrotary + rotary tillage without green manure crop (Con), with (ii) hairy vetch (ConHv), and (iii) hairy vetch + green barely (ConHvGb), (iv) rotary tillage without green manure crop (Rot), with (v) hairy vetch (RotHv), and (vi) hairy vetch + green barly (RotHvGb), and (vii) no-tillage (Notill). Vectorial distance result from PCA of soil properties including physical, chemical, and microbial properties showed the two main difference. Firstly, soil properties among plots without green manure were strongly affected by tillage strength [Vectorial distance: Con-Notil (5.88) > Rot-Notill (4.58)] at PC1 (35.0%) axis. But it was difficult to find the fixed trend among plots when green manure crop was added in plot. Nevertheless, two groups were separated by adding green manure crop at PC2 (29.2%) axis. These results show that PCA ordination methods could be used the research for change of soil characterization.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.110.1-110.1
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• 2010

A bench scale slurry bubble column reactor (SBCR) with active-Fe based catalyst was developed for the Fischer-Tropsch synthesis (FTS) reaction. Considering the highly exothermic reaction heat generated in the bench scale SBCR, an effective cooling system was devised consisting of a U-type dip tube submerged in the reactor. Also, the physical and chemical properties of the catalyst were controlled so as to achieve high activity for the CO conversion and liquid oil ($C_{5+}$) production. Firstly, the FTS performance of the FeCuK/$SiO_2$ catalyst in the SBCR under reaction conditions of $265^{\circ}C$, 2.5 MPa, and $H_2/CO=1$ was investigated. The CO conversion and liquid oil ($C_{5+}$) productivity in the reaction were 88.6% and 0.226 $g/g_{cat}-h$, respectively, corresponding to a liquid oil ($C_{5+}$) production rate of 0.03 bbl/day. To investigate the FTS reaction behavior in the bench scale SBCR, the effects of the space velocity and superficial velocity of the synthesis gas and reaction temperature were also studied. The liquid oil production rate increased upto 0.057 bbl/day with increasing space velocity from 2.61 to 3.92 $SL/h-g_{Fe}$ and it was confirmed that the SBCR bench system developed in this research precisely simulated the FTS reaction behavior reported in the small scale slurry reactor.

• 한국의류학회지
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• 제30권11호
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• pp.1589-1597
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• 2006

Nowadays, Korean consumers prefer drum-type washing machines to pulsator-type washers. Washing is a complex process involving the interaction of numerous physical and chemical influences. The main factors in the washing operations are the washing chemistry of the detergent along with the mechanical input, the wash temperature, and the time provided by the washing machine. Heavy-duty detergents that are used in drum-type washing machines contain different components from those used in vertical-axis washing machines. The bath ratio and the mechanical actions to which laundry is subjected are different between the drum-type and the vertical-axis washing machines. In this study we examined the effects of wash temperature, wash time, detergent concentration, and revolution speed on the removal of soils from artificially soiled cloths in a drum-type washing machine with heavy-duty commercial detergent. We used multiple regression analyses to find the relative importance of the factors and the optimum washing conditions. The results of these experiments showed that the washing temperature was the most important factor in the effective removal of most soils. This was followed by the washing time, the detergent concentration, and finally the revolution speed. In this study it was found that superfluous amounts of detergent did not sufficiently increase the soil removal rate. Koreans who are used to washing with cold water should increase the wash time to launder more efficiently.

• Journal of Plant Biotechnology
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• 제5권1호
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• pp.1-6
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• 2003

The adventitious root of Panax ginseng C.A. Meyer is regarded as an efficient alternative to cell culture or hairy root culture for biomass production due to its fast growth and stable metabolite production. To determine optimal culture conditions for the bioreactor culture of ginseng roots, experiments have been conducted on physical and chemical factors such as bioreactor type, dissolved oxygen, gas supply, aeration, medium type, macro- and micro-elements, medium supplement during culture period, sucrose concentration, osmotic agents, medium pH and light. Elicitation is a key step to increase ginsenoside accumulation in the adventitious roots but biomass growth is severely inhibited by elicitor treatment. To obtain high ginsenoside content with avoiding biomass decrease, we applied two-stage bioreactor culture system. Ginseng adventitious roots were cultured for 40 days to maximize biomass increase followed by elicitation for 7 days to enhance ginsenoside accumulation. We also experimented on types and concentrations of jasmonate to determine optimal elicitation methods. In this paper, we discussed several factors affecting the root propagation and ginsenoside accumulation. Based on the results obtained from previous experiments we have established large-scale bioreactor system (1 ton-10 ton) for the efficient production of ginseng adventitious roots and bioactive compounds including ginsenoside. Still, experiments are on going in our laboratory to determine other bioactive compounds having effects on diet, high blood pressure, DPPH elimination and increasing memories.

• 한국식품과학회지
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• 제22권1호
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• pp.105-109
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• 1990

Laboratary scale co-rotating twin-screw extruder(D=4mm, L/P=14)를 이용하여 쌀을 압출성형시켜 팽화 쌀 스넥으로 사용할 수 있는 extrudate를 제조하려고 시도하였다. 찹쌀가루를 원료로 하여 extrusion cooker의 screw speed를 200-360rpm으로 증가시키면, extrudate의 air cells 조직이 균일하게 개선되었으며, 원료의 수분함량은 적어도 17.5% 이하로 유지하는 것이 조직에 좋은 영향을 주었다. 찹쌀과 멥쌀의 powder와 grits를 원료로 사용했을 경우, extrudate의 객관적 및 관능적 텍스쳐는 powder가 grits보다 우수하였으며, 찹쌀과 멥쌀간의 차이는 현저하지 않았다. 그리고 extrudate를 기름에 튀기면 텍스쳐가 향상됨을 볼 수 있었다.

• 한국해양바이오학회지
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• 제12권2호
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• pp.81-90
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• 2020

Sialic acid, which is contained in about 60-160 mg/kg in the edible bird's nest (EBN), is known to facilitate in the proper formation of synapses and improve memory function. The objective of this study is to extract effectively the sialic acid from edible bird's nest using affinity bead technology (ABT). After preparing the non-polar polymeric bead "KJM-278-28A" having a porous network structure, and then desorbed sialic acid was concentrated and dried. The analysis of the physicochemical properties of bead "KJM-278-28A" showed that the particle size was 400-700 ㎛, the moisture holding capacity was 67-70%, the surface area (BET) was 705-900 ㎡/g, and the average pore diameter 70-87 Å. The adsorption capacity of the bead "KJM-278-28A" for sialic acid was shown a strong physical force to bind sialic acid to the bead surface of 400 mg/L. In addition, as a result of analyzing the adsorption and desorption effects of sialic acid on water, ethanol, and 10% ethanol on the bead, it was confirmed that desorption effectively occurs from the beads when only ethanol is used. As a result of HPLC measurement of the separated sialic acid solution, a total of four sialic acid peaks of N-acetyl-neuraminic acid (Neu5Ac), α,β-anomer of Neu5Ac and N-glycoly-neuraminic acid were identified. Through these results, it was confirmed that it is possible to separate sialic acid from EBN extract with efficient and high yield when using ABT.

• 한국식품영양과학회지
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• 제33권10호
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• pp.1742-1747
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• 2004

쥐치어의 이용을 다양화하기 위하여 분리대두단백과 쌀가루를 첨가하여 원료 혼합물의 수분함량을 20∼30%로 조절한 후 단축스크류 압출성형기를 이용하여 압출성형으로 조직화 단백질을 제조하기 위한 실험을 하였으며 쌀가루함량, 토출구온도 및 원료 혼합물의 수분함량이 압출성형물의 물리화학적 및 관능적특성에 미치는 영향을 반응표면분석을 이용하여 최적화하였다. 쌀가루함량이 증가하면 팽화율이 증가하므로 재흡수율은 높아지는 반면 밀도는 낮아지는 현상을 보였다. 재흡수율과 밀도는 서로 유의성 있게 반비례하는 상관관계 (p<0.01, R=-0.742)를 보였다. 육안적인 관능검사방법은 조직잔사지수와 유의성 있는 상관관계(p<0.01, R=0.489)를 보였으므로 비교적 조직화의 정도를 평가하는 방법으로 적절한 것으로 간주되었다. 그리고 관능검사와 재흡수율의 상관관계(p<0.01, R=0.507)와 밀도와의 상관관계(p<0.001, R=-0.596)가 각각 비교적 높게 나타났으며 압출공정에서 토출구의 온도가 13$0^{\circ}C$ 이상에서 최적의 조직화가 형성되었다.

• Journal of the Korean Wood Science and Technology
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• 제40권6호
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• pp.445-453
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• 2012

본 연구에서는 백합나무의 급속 열분해 공정에서 시료의 입자크기 및 함수율 조건이 열분해 산물(가스, 바이오오일, 바이오촤)의 수율과 물리 화학적 특성에 미치는 영향을 구명하였다. 시료의 함수율이 낮을수록 바이오오일의 수율은 증가하였으며 시료의 입자 크기는 수율 변화에 큰 영향을 미치지 않았다. 각 조건별로 생성된 바이오오일은 20~30%의 수분 함량과 pH 2.2~2.4, 발열량 16.6~18.5 MJ/kg의 수준을 나타내었으며 바이오오일 내 수분 함량은 높은 함수율 시료 조건에서 증가하는 것을 확인하였다. 바이오촤의 경우 80% 이상이 탄소로 이루어져있으며 발열량은 26.2~30.1 MJ/kg 수준으로 측정되었다.