• Journal of Microbiology and Biotechnology
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• 제2권3호
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• pp.197-203
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• 1992

Studies of the pretreatment of chitin and its subsequent hydrolysis by Aspergillus carneus chitinase are reported. Ball milling was found to be the most effective way among the pretreatment methods tested. Data are presented describing the effect of enzyme and substrate concentrations on the rate and extent of the hydrolysis process. It was found that the successive addition of enzyme improved the saccharification yield. Significant product inhibition of the chitinase was observed when N-acetylglucosamine concentration was 3.6％ or higher. Adsorption of enzymes to the substrate occurred during a 24 hr hydrolysis period. An initial rapid and extensive adsorption occurred, followed by gradual desorption which increased during the time of reaction. Intermediate removal of the hydrolyzate and continuation of the hydrolysis by adsorbed enzyme on the residual chitin was also investigated. A total of 75.4 g/l reducing sugars, corresponding to 69.2％ saccharificaton yield (as N-acetylglucosamine) was obtained. In addition an increase in the amount of recoverable enzymes was observed under these conditions. Evidence presented here suggests that the technique, whereby the free enzymes in the recovered hydrolyzate are re-adsorbed onto the new substrate, may provide a means of recirculating the dissolved enzymes.

• 한국미생물·생명공학회지
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• 제12권4호
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• pp.261-264
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• 1984

증자하지 않은 cassava 생전분의 ethanol 발효생산을 위한 동시당화 -발효의 최적조건을 검토하였다. 생전분의 분해력이 가장 좋은 당화효소의 선별에서는 Asp. shirousami27이 가장 좋았으며 발효효모는 균주에 따라 큰 차이가 없는 것으로 나타났다. 동시당화-발효는 pH3.6에서 가장 높았으며 발효전 6$0^{\circ}C$에서 당화효소에 의한 전당화와 발효시 교반등이 발효속도 및 발효율에 효과가 있었고, 분쇄처리도 효과가 있었다. cassava 생전분의 동시당화-발효에서 5일간의 긴 발효 기간을 요구하는데 발효중 발효액의 성분 조사 결과 중간물인 glucoserk 축적되지 않는 것으로 당화과정이 속도결정단계임을 알 수 있다.

• 한국식품영양과학회지
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• 제26권2호
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• pp.229-235
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• 1997

국내산 밀(그루, 수원 257, 은파, 조광, 탑동)과 수입 밀(ASW, DNS)을 70% 제분수율로 제분한 밀가루와 통밀의 단백질, 아미노산, 구성당 및 무기질 조성을 살펴본 결과 다음과 같다. 국내산 통밀중 은파와 탑동의 경우 단백질 함량이 약 15%을 나타내었고, 제분한 밀가루는 약 1% 가량 낮은 함량을 보였다. 국내산 밀가루에 있어서 아미노산 조성은 점탄성에 영향을 주는 것으로 알려진 글루탐산과 프롤린의 함량이 높았고, 제한 아미노산은 국내산이 ASW 보다는 높고 DNS 보다는 낮게 나타났는데 특히, 수원 257과 탑동의 제한 아미노산 함량이 높았다. 제분 전후의 아미노산 함량에 있어서 글루탐산과 프롤린은 증가하나 리진과 트레오닌 등의 제한 아미노산 양은 감소하였다. 구성당의 조성은 통밀의 경우 밀가루 보다 아라비노스와 자일로스의 함량이 높았으며 글루코스의 함량이 낮게 나타났다. 한편, 국내산 밀은 외국산 밀에 비하여 아라비노스와 자일로스의 함량이 높게 나타났다. 국내산 밀가루와 통밀에 있어서 무기질 함량 중 인, 칼륨, 칼슘의 함량은 ASW와 DNS에 비하여 모두 높게 나타났으며, 알루미늄과 실리카의 함량은 비슷하거나 소량 증가하였다.

• 한국식품과학회지
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• 제39권4호
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• pp.412-418
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• 2007

연질밀인 soft white winter(SWW) 밀과 club 밀 각각 6품종을 공시재료로 하여 종실의 이화학적 품질특성, 제분특성, 호화특성, mixograph 특성 및 제품특성으로 sugar-snap 쿠키와 스펀지 케이크의 제조특성을 측정하고 이들 특성간의 상관관계를 검토하였다. Single Kernel Characterization System(SKCS)에 의한 종실의 경도, 무게 및 크기는 SWW밀과 club 밀의 평균간의 유의성은 적었으나 품종간에는 차이가 비교적 컸다. Straight-grade flour yield, break flour yield, 회분 함량 및 제분평점 등의 제분특성은 SWW 밀과 club 밀 간에 차이가 없었다. Straight-grade flour yield와 break flour yield는 고도의 정의 상관(r = 0.805**)이 있었다. SWW 밀과 club 밀의 Rapid Visco Analyze(RVA) 최고점도와 팽창부피는 유의적인 차이가 없었으며 품종간의 변이도 적었다. RVA 최고점도와 팽창부피는 고도의 정의 상관(r = 0.662**)이 있었다. Mixograph 흡수율은 SWW 밀이 club 밀보다 다소 높았으나 mixograph type은 2M 이하로서 전형적인 연질의 특성을 보였다. Club 밀의 쿠키 직경과 쿠키 top grain score는 SWW 밀보다 좋았으나 통계적인 유의성은 없었다. 스펀지 케이크의 부피는 SWW 밀보다 club 밀이 높았으나 케이크 score는 club 밀이 높은 경향을 보였다. 쿠키 직경과 스펀지 케이크의 부피는 고도의 정의 상관(r = 0.745**)이 있었다.

• 한국식품영양학회지
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• 제29권5호
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• pp.777-784
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• 2016

본 연구는 국내산 밀 품종에 따른 제분율 별로 밀 막걸리의 품질특성을 평가하고자 수행하였다. 원료곡의 탄수화물은 70% 제분율의 금강밀, 백중밀이 78.37, 78.16%로 가장 높았다. 밀의 품종 및 제분율에 따른 막걸리의 품질특성을 검정한 결과, 가용성 고형분 함량, 환원당, 알코올은 각각 $10.94{\sim}12.33^{\circ}Brix$, 2.89~4.71%, 14~15.97% 범위를 나타냈으며 백중밀 70% 제분율에서 알코올 15.97%, 환원당 4.71%로 가장 높은 함량을 나타냈다. 밀 막걸리의 glucose 함량은 159.4~560.7 mg%의 범위를 보이며 원료 밀 대비 상당량 증가하였고 그 외 mannitol과 arabinose도 존재하였다. 밀 막걸리의 유기산 분석에서, 유산균에 의한 대사산물인 lactic acid는 85.3~650.3 mg%의 분포를 나타내며 가장 높은 수준을 나타냈고 제분율 증가에 따라 그 함량도 증가하였고 제분율별 품종 비교에서는 조경밀이 가장 높았다. 밀 막걸리의 품질 관련인자의 상관성 분석에서는 원료곡의 단백질 함량은 밀 막걸리의 총산, 환원당과 부의 상관을 보였고(p<0.001), 원료곡의 탄수화물 함량은 밀 막걸리의 총산, 환원당(p<0.001) 및 알코올 함량(p<0.05)과 정의 상관을 나타내었다. 가용성 고형물의 함량은 알코올, 환원당 함량과 정의상관을, pH와는 부의 상관관계를 나타내었다(p<0.001). 밀 막걸리의 알코올 함량 비교 시 70, 85% 제분율에서 품종과 제분율에 따른 차이가 존재하지 않았으므로 85% 밀가루도 막걸리용으로 이용 가능할 것이라 생각된다. 하지만 품종과 제분율에 따라 함유하는 유리당과 유기산 등 여러 가지 품질특성이 상이하기 때문에 이를 고려한 원료의 선택이 필요할 것이다.

• 한국정밀공학회지
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• 제24권10호
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• pp.109-116
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• 2007

Focused ion beams are a potential tool for micro/nano structure fabrication while several problems still have to be overcome. Redeposition of sputtered atoms limits the accurate fabrication of micro/nano structures. The challenge lies in accurately controlling the focused ion beam to fabricate various arbitrary curved shapes. In this paper a basic approach for the focused ion beam induced direct fabricate of fundamental features is presented. This approach is based on the topography simulation which naturally considers the redeposition of sputtered atoms and sputtered yield changes. Fundamental features such as trapezoidal, circular and triangular were fabricated with this approach using single or multiple pass box milling. The beam diameter(FWHM) and maximum current density are 68 nm and $0.8 A/cm^2$, respectively. The experimental investigations show that the fabricated shape is well suited for the pre-designed fundamental features. The characteristics of ion beam induced direct fabrication and shape formation will be discussed.

• Journal of Plant Biology
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• 제13권1호
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• pp.1-12
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• 1970

The Nongkwang variety was sown directly in the field by the three methods of dibbling, drill seeding and broad-casting in non-, low- and high-salty areas, and compared with the growth of transplanted rice in each areas. The yield of rough rice was increased remarkably by direct sowing when compared with that produced by transplanting inboth salty areas, but in non-salty area, the former was decreased significantly. There was no significant difference in the yields of rough rice resulting from three seedling methods of direct sowing in each area. The direct sowing method was predominated in number of panicle, weight of panicle, ratio of matured grains, milling recovery percentage, and straw weight in both salty areas, and dicreased in panicle weight and ratio of matured grain in nonsalty area.

• International Journal of Precision Engineering and Manufacturing
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• 제9권4호
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• pp.83-85
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• 2008

Redundant spurious loops and overlapping segments in stability lobe diagrams cannot be removed easily by regular methods. A programmatic approach is presented to detect multiple spurious loops occurring within the lobes. They are identified by reorganizing the numerical lobe data into speed-depth corners for subsequent removal. The same principle is then extended to remove overlapping segments of adjacent lobes to obtain a final continuous stability map. Unlike existing methods, the proposed methodology requires no interface with additional editing software, and can also yield stability lobe diagrams more quickly. The methodology is presented with lobe diagrams constructed using milling and turning models.

• 농업과학연구
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• 제39권3호
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• pp.387-393
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• 2012

In the present study, ${\beta}$-glucanase-assisted extraction of starch from glutinous barley(Hinchal ssalbory) was investigated. ${\beta}$-glucanase was added to a coarse starch suspension obtained after wet milling in the starch extraction process. It was found that in the isolated starch with enzyme treatment, protein content was lower by 0.03%, compared to that with non-enzyme treatment. More importantly it was observed that the extraction yield of starch from enzyme treatment was found to be about 12% higher than the one from non-enzyme treatment (enzyme treated: 90.56%, non-enzyme treated: 78.46%). In order to elucidate this finding, the mass-balance determination of starch in each extraction step was carried out and found that the enzyme treatment might influence on the insoluble residues(R3 and R4 fractions) to hydrolyze ${\beta}$-glucan and other materials (e.g., mucilages etc.), thereby facilitated the separation of starch from it and a next filtration process. With a phase-contrast microscope it was observed that the isolated starch with enzyme treatment contained small starch granules more than the one with non-enzyme treatment and this might result in higher extraction yield observed with the former. In order to confirm this hypothesis, further experiments would be necessary.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.136-139
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• 2003

Copper has attractive properties as a multi-level interconnection material due to lower resistivity and higher electromigration resistance as compared with Alumina and its alloy with Copper(0.5%). Among a variety of agents in Copper CMP slurry, $H_2O_2$ has commonly been used as the oxidizer However. $H_2O_2$ is so unstable that it requires stabilization to use as oxidizer Hence, stabilization of $H_2O_2$ is a vital process to get better yield in practical CMP process. In this article the stability of Hydrogen Peroxide as oxidizer of Copper CMP slurry has been investigated. When alumina abrasive was used, $\gamma$-particle Alumina C had a better stability than $\alpha$-particle abrasive. As adding KOH as pH buffering agent, $H_2O_2$ stability in slurry decreased. Urea hydrogen peroxide was used as oxidizer, an enhanced stability was gotten. When $H_3PO_4$ as $H_2O_2$ stabilizer was added, the decrease of $H_2O_2$ concentration in slurry became slower. Even though adding $H_2O_2$ in slurry after bead milling lead to better stability than in advance of bead milling, it had a lower dispersibility.