• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.418-422
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• 2005

In this study, the die design and die series on the surface residual stress of cold drawn eutectoid steel wire has been investigated. Test pieces were fabricated using die series with different mean and final reduction ratio. Surface residual stresses in the axial direction were measured by X-ray diffraction, Broker's 2-dimensional GADDS system. Results were compared with stress profiles which were calculated by 3D and 2D finite element simulation, Hibbitt's ABAQUS 6.4 program in Finite Element Analysis. By means of FEA method, optimal die shape considering delta-parameter were induced and applied in order to determine die sequence designs. Balance of the drawing stresses was also introduced to optimize die sequence.

• Journal of Plant Biology
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• 제37권1호
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• pp.27-36
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• 1994

For establishing a transformation system of rice, an efficient introduction of foreign genes into embryogenic cell suspension by particle bombardment was conducted. The particle inflow gun based on the acceleration of DNA-coated tungsten particles using pressurized helium was constructed for delivery of DNA into rice cells. Several bombardment parameters were optimized using the transient expression of GUS gene. The conditions that gave the highest GUS gene expression of about 1000 blue spots per g fresh weight of bombarded cells include treatment of the cells with 0.5 M osmotic pressure, and use of the 410 kPa helium, 110 mm target distance, 13 mm syringe filter holder and 5 $\mu$L DNA/tungsten mixtures. It was also confirmed that rice actin promoter-intron construct gave the highest expression of all promoter-sequences studied. Eight weeks after the bombardment, stably transformed calluses were obtained on the selection medium containing 100 mg/L G418 and showed the strong activity in in situ GUS assay.

• Journal of Microbiology and Biotechnology
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• 제28권3호
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• pp.418-424
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• 2018

${\text\tiny{D}}-Allose$ is a potential medical sugar because it has anticancer, antihypertensive, antiinflammatory, antioxidative, and immunosuppressant activities. Allose production from fructose as a cheap substrate was performed by a one-pot reaction using Flavonifractor plautii ${\text\tiny{D}}-allulose$ 3-epimerase (FP-DAE) and Clostridium thermocellum ribose 5-phosphate isomerase (CT-RPI). The optimal reaction conditions for allose production were pH 7.5, $60^{\circ}C$, 0.1 g/l FP-DAE, 12 g/l CT-RPI, and 600 g/l fructose in the presence of 1 mM $Co^{2+}$. Under these optimized conditions, FP-DAE and CT-RPI produced 79 g/l allose for 2 h, with a conversion yield of 13%. This is the first biotransformation of fructose to allose by a two-enzyme system. The production of allose by a one-pot reaction using FP-DAE and CT-RPI was 1.3-fold higher than that by a two-step reaction using the two enzymes.

• 한국식품조리과학회지
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• 제20권4호
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• pp.418-422
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• 2004

We investigated microbial populations of an upland and cultivated Codonopsis lanceolata. The microbial populations from both types of soils were also investigated. There were more than 10 microorganisms existed in upland than cultivated one. The total viable cell counts of C. lanceolata from upland and cultivated one, especially in the upper zone, were 9.7x10$\^$6/ CFU/g and 4.2${\times}$10$\^$6/ CFU/g, respectively. As a results, upper parts of C. lanceolata in upland were considered to harbour approximately more than 2.3 fold higher microorganisms than in cultivated one. However, the total viable cell counts between the two soil habitat, that is, 1.2${\times}$10$\^$7/ CFU/g from upland and 1.0x10$\^$7/ CFU/g from cultivated, were not significantly different. We also examined the unique flavor producing microorganisms in the soil extract broth including 25% C. lanceolata extract. One microorganism was detected in upper pars of C. lanceolata and upland soil. No. 6, microorganism causing the characteristic flavor of C. lanceolata was continued as Actinomyces by microscopy.

• 동아시아식생활학회지
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• 제10권5호
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• pp.411-418
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• 2000

The purpose of this study was to investigate the sensory and mechanical characteristics of mayonnaise containing various levels of green tea powder The highest viscosity of mayonnaise was obtained at the green tea powder concentration of 0.5% The emulsion, stability was increased with the addition of green tea powder. In the sensory evaluation, overall acceptabilty appeared to be the highest when 0.1% of green tea powder was added. There was a significant difference between the samples (P<.05) In terms of change in color, the values of L, a, b, and ΔE decreased as the amount of green tea powder increased. In the measurement of the texture, the hardness of mayonnaise was highest in the control of green tea powder, and the springiness appeared to be higher in the mayonnaise with 0.1% of green tea powder. The odor acceptabilty in the sensory evaluation showed a negative correlation with the values of gumminess in the mechanical characteristics. The subjective parameters that affect overall quality on sensory evaluation were determined by, and they were odor acceptabilty, after taste, oily taste, sour odor. sweet taste. egg odor, color acceptabilty, and salty taste. These results showed that mayonnaise made with 0.1% green tea powder, salad oil 474.5ml. egg golk 85g, sugar l0g, salt 7g, and vinegar 23m1 with the addition of 0.6g green tea powder was the most effective compared with other treatments.

• 폴리머
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• 제39권3호
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• pp.418-425
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• 2015

Polycaprolactone(PCL)과 biphasic calcium phosphate(BCP)는 생체적합성 및 골 형성 촉진 등으로 인해 정형외과 소재로 사용되고 있다. 하지만, PCL은 표면이 소수성으로 인해 세포의 부착 및 증식에 제한적이기 때문에 이를 극복하기 위해 본 연구에서는 감마선을 이용하여 골 재생을 위한 친수성이 향상된 PCL/BCP 나노섬유를 제조하였다. 나노섬유는 전기방사를 통해 제작했으며, 감마선을 이용하여 acrylic acid(AAc)를 도입하였다. SEM을 통해 나노섬유 표면을 확인하였고, AAc가 도입된 나노섬유 위에서 MG63의 초기 생존율이 현저히 증가한 것을 확인하였다. 알칼리성 포스파테이즈 활성은 $1.239{\pm}0.226nmole/{\mu}g/min$으로 개질되지 않은 나노섬유($0.590{\pm}0.286nmole/{\mu}g/min$) 보다 증가하였다. 따라서, AAc가 도입된 PCL/BCP 나노섬유는 골조직 재생에 활용될 수 있을 것으로 기대된다.

• 한국수정란이식학회지
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• 제22권3호
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• pp.179-184
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• 2007

체세포의 배양 방법은 체세포 핵이식에 의한 형질 전환 돼지 생산에 있어서 중요한 요인 중 하나이다. 본 연구에서는 돼지 태아 섬유 아세포의 효율적인 배양 방법을 수려하였다. 돼지 태아 섬유 아세포는 임신 33일째 태아로부터 제조하였으며, 돼지 태아 섬유아세포의 증식을 혈청과 배지 종류별로 분석하였다. 그 결과, 15% ES screened FBS가 포함된 DMEM 배지에서의 배양은 15% FBS보다 세포수의 증가가 훨씬 더 빠르게 나타났다. 또한, 태아 섬유아 세포는 DMEM/F-12와 다르게 ES midified DMEM과 DMEM 배지에서 $7{\sim}8$번째 계대까지 증식이 유지되었다. 이러한 배양 조건에서 PGK-neo 벡터(pKJ2)를 돼지 태아 섬유아 세포에 도입한 다음 12일간 $300\;{\mu}g/ml$ G418이 포함된 배지에서 선별하여 colony를 얻을 수 있었다. 이러한 결과는 본 연구에 이용된 배양 시스템이 transgenic vector를 도입시킨 돼지 체세포의 screening에 이용될 수 있음을 보여주고 있다.

• 대한환경공학회지
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• 제37권7호
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• pp.418-425
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• 2015

본 논문에서는 양돈폐수의 전처리 공정으로 부유성 세라믹 담체로 충진한 Anaerobic Filter (AF)을 이용하여 신재생에너지 메탄가스의 생산 가능성과 전처리 후 유출수의 후속 고도처리 적정성을 평가하였다. 유입 COD 농도가 14,000 mg/L인 양돈폐수를 Anaerobic Filter에 점진적으로 유기물부하(OLR)를 증가시키면서 혹은 수리학적 체류시간을 짧게 유지하면서 $35^{\circ}C$에서 운전한 결과는 다음과 같다. Anaerobic Filter는 HRT 0.5일(OLR 28 g TVS/L-d)에서 최대 메탄발생량 1.74 v/v-d를 달성하였으며, Biogas 기준 TVS 제거효율은 HRT 3일(OLR 4.67 g TVS/L-d)로 운전하였을 때 63%를 얻었다. 반면 유출수 분석에 의한 TCOD 제거효율은 75%를 상회하였다. 유출수의 알카리도는 모든 운전 조건에서 2,050~2,980 mg/L as $CaCO_3$로서 후속 질소제거 시 야기될 수 있는 알카리도 파괴를 상쇄할 수 있을 것이다. HRT 2일 이하의 운전조건에서 Anaerobic Filter 유출수의 COD/TKN 비는 10~35 범위로서 고도처리 시 적정비인 8 이상을 만족하였으며 COD/TP 비는 38~56범위로서 적정비 33 이상 유지가 가능하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권6호
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• pp.418-421
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• 2000

A new direct colorimetric assay of microcystin in water and algal samples is proposed consisting of two procedures as follows: 1) the elimination of phosphorus in the sample and concentration of microcystin using a C(sub)18 cartridge, 2) the detection of the released phosphorus by the ascorbic acid method and determination of protein phosphatase (PP) inhibition by microcystin. The optimum amounts of phosphorylase ${\alpha}$ and PP-1 in 50 ${\mu}$L concentrated sample were 50$\mu\textrm{g}$/50${\mu}$L buffer and 1.0unit/50${\mu}$L buffer, respectively, for the best assay. The pH for the maximum activity of PP-1 was 8. The minimum detectable concentration for this method was about 0.02$\mu\textrm{g}$/L, which is sufficient to meet the proposed guideline level of 1$\mu\textrm{g}$ microcystin/L in drinking water. Consequently, it would seem that the proposed direct colorimetric assay using PP is a rapid, easy, and convenient method for the detection of microcystin in water and algal samples.

• 수산해양교육연구
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• 제15권2호
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• pp.135-144
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• 2003

1. The appearance of fisheries animals and plants of investigation areas were fishes, 20 species; algae, 9 species; molluska, 6 species; arthropod, 12 species; echinoderm, 5 species by confirmed appearance species. 2. The C.P.U.E by trap(1pcs of trap) were 3.95 species and weight of 2,098g, mainly catching species are greenling and jacopever(94.16%). The C.P.U.E by long liner(long liner 1coil, 100pcs) were 11.7species and weight of 6,418g, It occupied jacopever(35.63%) greenling(20.78%), bastard halibut(20.31%). The C.P.U.E of appearance species gill net(ipcs of gill net) were 5.05species and weight of 3,050g, It occupied jacopever(39.63%) greenling(29.83%), bastard halibut(17.47%). 3. The results of comparative analysis and natural species and stocked species, in case of bastard halibut, jacopever species were occupied species(83.33~92%), weight(86.86~96%). The stocked species were occupied species of 8.00~16.67%, weight of 4.00~13.14%. Provided the stocked projets were enacted effectively in future. The density of dwelling of stocked species were increase. Also, it will be contribute to the increase of fishermens income.