• 한국식품과학회지
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• 제21권4호
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• pp.528-535
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• 1989

감자(세풍과 대지)에서 분리한 전분을 큰 입자와 작은 입자로 분획하고 입자별 일반성질과 호화특성을 비교하였다. 전분입자의 크기는 세풍전분이 $10{\sim}85{\mu}m$, 대지전분이 $13{\sim}90{\mu}m$이었고, 작은 입자$(<30{\mu}m)$는 대지전분이, 큰 입자$(>41{\mu}m)$는 세풍전분이 많았다. 일반성질과 물결합 능력은 차이가 없었고, 아밀로오스 함량은 큰 입자가 높았다. 팽윤력은 큰 입자가 작은 입자보다 낮았고, 아밀로그램의 최고점도는 세풍전분은 입자별로 차이가 없었으나, 대지전분은 큰 입자가 높은 값을 보였다. 호화온도 범위는 작은 입자가 큰 입자보다 넓었으나, 호화 엔탈피는 차이를 보이지 않았다. 두 전분 모두 입자별에 관계없이 $70^{\circ}C$에서 호화가 완료되었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제11권2호
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• pp.87-91
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• 2005

We have first isolated and characterized a Plutella xylostella granulovirus ($P_xGV$) from dead larvae of P. xylostella in Korea. The granule of $P_xGV$ was ovoidal shape with an approximate measure of $350-400nm{\times}150-200nm$, and each granule contained one single rod-shape virion with a mean size of $150-180nm{\times}20-30nm$. The major granule protein, granulin, had a molecular weight of approximately 29kDa. Whereas the nucleotide sequence of the granulin gene was identical to that of previously reported $P_xGV$, nucleotide sequences of two of three putative p10 genes were slightly different from those of reported $P_xGV$. These results suggested that the $P_xGV$ isolated in this study was a novel isolate containing different genomic information.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.332-332
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• 2017

Rice ratooning is the cultural practices to produce easily second rice from the stubble left behind after the main-crop harvest. The main advantage of rice ratooning is that in areas where rice is the main crop, double crop of rice can be grown for additional returns. Three early ripened rice cultivars were tested for estimation their milled rice quality and starch characteristics from main and ratoon rice. The main crop was harvested at mass maturity, after which the tillers were mowed to stubbles of about 10 cm tall. And then it left without any further input until the ratooned plant was ready for harvest. Highly significant variations were detected in the milled rice quality between main and ratoon rice. Protein and amylose contents of ratoon rice were more increased than those of main rice. The Toyo value (gloss) of cooked rice of ratoon crop was measured also higher than that of main crop. It resulted from higher air temperature during grain ripening compared with that of ratoon crop. The mean temperature during ripened period of ratoon rice was favorable for optimal maturation for early ripened rice cultivars. Normalized chromatograms of branch chain length distribution of amylopectin are demonstrated a distinct difference between main and ratoon rice flour. Ratoon rice had higher amount of short chains than that of main crop rice starches. Microscopic examination of rice flours with scanning electron microscopy shows starch granule shapes affected by the cropping types, main and ratoon rice. It showed significant differences among rice starch granule shapes and in granule size between main and ratoon rice. Starch of ratoon rice had more neat and smaller granules than that of main rice.

• 한국식품과학회지
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• 제21권1호
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• pp.52-57
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• 1989

보리 전분입을 구성하는 대입자와 소입자의 물리, 화학적 차이에 관해서 비교하였다. 대입자의 직경은 약 $28-30{\mu}m$이고. 소입자는 약 $6{\mu}m$ 이었으며, Hiproly 전분 입자의 수에 대한 소입자의 수는 95%정도 이었다. 아밀로오즈의 함량은 대입자가 소입자 보다 높게 나타났다. 아밀로오즈의 분자 형태에 관한 대입자 소입자 전분의 고찰로써, iso-amylase처리 전분의 구성성분의 차이, X선 회절도의 차이, 호화특성, 산분해성 등의 검토에 의하면, 아밀로펙틴의 미세결정 구조인 망상구조상에 있어서 대입자와 소입자가 서로 다른 구조를 하고 있으리라 예측된다.

• 대한환경공학회지
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• 제28권4호
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• pp.438-446
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• 2006

팔당호 경안천 하류 정체수역에서 퇴적물 인 용출 저감을 위한 capping 소재를 개발하고자 실험실 규모의 batch test를 수행하였다. 조사지역 퇴적물 평균 입도는 7.7 ${\phi}$로 매우 세립하고, 유기탄소 함량은 2.4%로 매우 높게 나타났다. 최적의 capping 소재 선정을 위한 인 용출 실험을 위해 150 L 반응기 5개에 모래층, powder-gypsum($CaSO_4{\cdot}2H_2O$), granule-gypsum, 복합층(gypsum+sand)로 capping을 한 경우와 control을 45일간 비교 평가하였다. 모래로 capping할 경우, 퇴적물로부터 용출되는 인을 약 50% 차단 가능한 것으로 나타났다. 그러나 모래층 1 cm로는 $CH_4$ gas 발생으로 인한 퇴적물의 재부유와 유기물 분해에 의한 수층 용존산소 감소(3 mg/L 이하)를 초래하는 것으로 나타났다. 따라서 모래로 capping을 할 경우에는 모래층이 더 높아져야 할 것으로 판단된다. powder-Gypsum과 granule-Gypsum은 80% 이상의 인 용출 저감 효과를 보였으나 수층 ${SO_4}^{2-}$ 농도가 증가되어 상수원보호구역에 적용하기 어려운 것으로 나타났다. 따라서 ${SO_4}^{2-}$의 용해도를 감소시키기 위해 Fe-Gypsum, $SiO_2$-gypsum 소재를 개발하였다. powder-Gypsum은 물과 결합시 경화되어 퇴적물 층위에 공극이 전혀 없는 차단막을 만들기 때문에 gypsum 층에 crack이 생길 경우, $CH_4$ gas 발생으로 인한 인 용출이 한꺼번에 일어날 수 있다. 복합층(granule-Gypsum+sand(1 cm))으로 capping을 할 경우, 인 용출 차단 효과가 높을 뿐만 아니라, ${SO_4}^{2-}$ 농도 역시 powder-Gypsum, granule-Gypsum 보다 수층으로 용출이 적어 상수원보호구역에 적합한 것으로 나타났다. Gypsum으로 capping을 할 경우, 빠른 초기속성작용(early diagenesis)과 ${SO_4}^{2-}$ 농도가 퇴적물에 충분히 공급되어 SRB(sulfate reducing bacteria)의 활성이 높아져 methanogensis의 진행을 저하시킬 수 있는 것으로 나타났다.

• 한국세라믹학회지
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• 제53권3호
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• pp.332-337
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• 2016

As a case study on yttria stabilized zirconia ceramics, the sintering characteristics of submicron powders and the granulation prepared by two-fluid spray drying of submicron particles were investigated. As-received powders of yttria stabilized zirconia particles were reduced to a uniform size of less than about 200 nm by repeated milling. Granulation size obtained by the two-fluid spray drying was affected by the organic matter and the primary particle size. Sintering behavior such as porosity, water absorption ratio, density, and transparency was influenced by processing conditions of the powder, and the discontinuous interfaces in a green body were reduced.

• 한국전기전자재료학회논문지
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• 제17권8호
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• pp.882-887
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• 2004

The new magnetic porcelain materials have been studied by mixing magnetic St-ferrite powders with traditional porcelain materials before forming process. For the maintenance of magnetic characteristics after glaze firing process, the Sr-ferrite grains with the size of 1∼2 ${\mu}{\textrm}{m}$ were agglomerated as the isotropic granules with the size of 0.5∼2 mm. The high characteristics of magnetic porcelain materials were achieved at the following conditions; isotropic Sr-ferrite granules of 30 wt%, granule size of 1.4∼2 mm, and glaze firing temperature of $1250^{\circ}C$ in air The magnetic porcelain materials indicated the high magnetic properties, such as the remanent flux density of 240 G, the intrinsic coercivity of 3910 Oe, and the surface flux density of 178 G. The extraction properties of the magnetic tea cups were high compared to that of the traditional tea cups.

• Journal of Oral Medicine and Pain
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• 제8권1호
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• pp.33-41
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• 1983

The authors observed the ultrastructure of oral leukoplakia simplex of gingiva, buccal mucosa, tongue and alveolar ridge. For the purpose of clearly defining the lesions under investigation in this study, leukoplakias were cinsidered to be any white patches on the oral mucous membranes that could not be removed by rubbing and could not be classified clinically or microscopically as another diagnosable disease. The tissue to be examined were embedded in paraffin for light microscopic study. The tissue to be examined under the electronomicroscope were fixed in 2.5% glutaraldehyde in 0.1M cacodylate buffer and 1% osmic acid in 0.1M cacodylate buffer, dehydrated with guaded alchol, and treated with propylene oxide, and embedded in Epon.Ultrathin sections were obtained by LKB III ultrotome, stained with uranyl acetate/lead citrate, and examined with Corinth 500EM. The results were as follows : 1. Epithelium of leukoplakia consisted of stratum basale, stratum spinosum, stratum granulosum and stratum corneum. 2. There was hyperorthokerotosis or hyperparakeratosis. 3. Granular cells contained a lot number of membrane coating granule showing lamellar structure, clearing ot codensation, and a lot of keratohyaline granule varied in size. 4. An increased concentration of tonofilaments and an increased number of desmosomes were found in the stratum spinosum. 5. Basal lamina generally showed its continuity, but in some locatoins, its interreption and multiplication appeared.

• Journal of Microbiology and Biotechnology
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• 제13권3호
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• pp.378-384
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• 2003

Mesophilically-grown granular sludge seeded in thermophilic UASB reactor was monitored to better understand the start-up process of the reactor. The reactor was fed with a synthetic wastewater containing glucose. As COD loading rate increased stepwise, methane production rate increased. Maximum values of COD removal efficiency (95%) and methane production rate (5.3 l/day) were achieved by approximately day-80 and remained constant afterward. However, physicochemical and microbial properties of granules kept changing even after day-80. Specific methanogenic activity (SMA) was initially negligible, and increased continuously until day-153 and remained constant afterward, showing the maximum value of $1.51{\pm}0.13\;g\;CH_4-COD/g$ VSS/day. Deteriorated settling ability of granules recovered the initial value by day-98 and was maintained afterward, as determined by sludge volume index. Initially reduced granule size increased until day-126, reaching a plateau of 1.1 mm. Combined use of fluorescence in situ hybridization and confocal laser scanning microscopy (CLSM) allowed to localize families of Methanosaetaceae and Merhanosarcinaceae in granules with time Quantitative analyses of CLSM images of granule sections showed abundance patterns of the methanogens and numerical dominance of Methanosaeta spp. throughout the start-up period. The trend of SMA agreed well with abundance patterns of the methanogens.

• 한국식품과학회지
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• 제23권2호
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• pp.175-182
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• 1991

옥수수 전분을 propylene oxide와 반응시켜 치환도가 $0.031{\sim}0.147$되는 hydroxypropyl 옥수수 전분을 제조하여 물리화학적 특성을 규명하였다. Hydroxypropylation에 의하여 팽윤력, 용해도 및 물결합 능력이 증가하고 생전분의 효소 분해력이 높아졌으며 요오드 흡착강도가 낮아졌다. 아울러 hydroxypropylation에 의하여 전분의 결정화도도 감소되었다. 한편, 옥수수 전분을 hydroxypropylation시켰을 때 분자량 $1.34{\times}10^7$ 이상의 큰 분자는 감소하였고 $1.34{\times}10^7{\sim}1.18{\times}10^5$의 전분 분자는 증가하였다. Hydroxypropylation에 의하여 옥수수 전분 입자의 형태에는 별 변화가 없었으나 입자크기는 평균입경이 $13.9\;{\mu}m$에서 $16.0\;{\mu}m$로 증가하였다.