• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.77-80
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• 2000

Various analytical methods such as electron microscopy, quinone analysis, and 16S rDNA sequencing studies were used to investigate the microbial communities and to identify the microorganisms responsible for enhanced biological phosphorus removal (EBPR) in an anaerobic/aerobic sequencing batch reactor (SBR) fed with acetate. Electron photomicrographs showed that oval-shaped microorganisms of about $0.7\;{\sim}\;1\;{\mu}m$ in diameter dominated the microbial sludge. These microorganisms contained polyphosphate granules and glycogen inclusions, which suggests that they are a kind of phosphorus accumulating organism. Quinone and 16S rRNA sequence analyses showed that the members of Proteobacteria beta subclass were the most abundant species, which were affiliated with the Rhodocyclus-likes group. Phylogenetic analysis revealed that the two dominating clones of the beta subclass were most distantly related to Propionivibrio dicarboxylicus DSM 5885 and Rhodocyclus tenuis DSM 109 with about 95% and 96% sequence similarity, respectively. Therefore, it was concluded that the oval-shaped organisms related to the Rhodocyclus-likes group are likely to be responsible for biological phosphorus removal in SBR operation supplied with acetate.

• Transactions on Electrical and Electronic Materials
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• 제14권2호
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• pp.82-85
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• 2013

This paper introduces 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) doped liquid crystal (LC) alignment properties on a rubbed polyimide (PI) layer as a function of the doping concentration of TIPS pentacene. Pretilt angles, photomicrographs, and electro-optical properties of TIPS pentacene doped LCs were comparable to those of pure LCs. However, TIPS pentacene in a LC medium supported twisted nematic-liquid crystal displays (TN-LCDs) to improve electro-optical properties. The threshold voltages observed in the TN cells decreased as the TIPS pentacene concentration increased. In addition, suitable response times were observed in TN cells.

• 한국응용과학기술학회지
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• 제25권2호
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• pp.160-167
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• 2008

Nanocomposites with polypropylene/clay/wood flour were prepared by melt blending and injection molding. Thermal, mechanical and morphological properties were characterized. The addition of ballmilled clay, compatibilizer and wood flour significantly improved the thermal stability of the hybrids. The tensile modulus and strength of most hybrids was highly increased with the increased loading of clay, maleated polypropylene (MAPP) and wood flour (WF), compared to the PP/WF hybrids. The tensile modulus and strength of most hybrids were highly increased with the increased loading of ballmilled clay, MAPP and wood flour, compared to the hybrids with PP/WF. The transmission electron microscopy (TEM) photomicrographs illustrated the intercalated and partially exfoliated structures of the hybrids with ballmilled clay, MAPP and wood flour.

• 식물분류학회지
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• 제49권2호
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• pp.198-201
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• 2019

We report Scutellaria krasevii Kom. & I. Schischk. ex Juz. (subfamily Scutellarioideae, family Lamiaceae) as a new recorded species of Mongolia. This species is morphologically similar to S. galericulata but can be differentiated by the presence of comparatively thick and triangular-cordate leaves having a heteromerously deep-crenate margin, a densely reclinate pubescent stem, and a densely pubescent corolla. A taxonomic description, a key to the genus in Mongolia, habit photographs, and scanning electron photomicrographs of nutlets are provided for species identification. We also present a table for a comparison of the diagnostic characteristics with those of related species. This species grows along the banks of the Unit river, Khutag-Undur soum, Bulgan province, Mongolia, approximately 2,300 km far away from the type locality in Russia.

• Journal of Species Research
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• 제10권4호
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• pp.392-404
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• 2021

Rotifers collected from mosses, leaf litter, soil, and wetland at six different locations in Korea were investigated. Ten species belonging to six genera in four families of monogonont and bdelloid rotifers were new to Korea: Habrotrocha scepanotrochoides De Koning, 1947, H. tripus (Murray, 1907), Lecane opias (Harring and Myers, 1926), L. perpusilla (Hauer, 1929), Macrotrachela decora (Bryce, 1912), Otostephanos auriculatus auriculatus(Murray, 1911), O. torquatus amoenus Milne, 1916, Scepanotrocha corniculata Bryce, 1910, S. simplex De Koning, 1947, and Testudinella brevicaudata Yamamoto, 1951. Among these 10 Korean new records, Habrotrocha scepanotrochoides, H. tripus, Macrotrachela decora, Otostephanos auriculatus auriculatus, O. torquatus amoenus, Scepanotrocha corniculata, and S. simplex were new to Asia as well. The present study is the first report of the genus Scepanotrocha Bryce, 1910 from Korea. Here, diagnostic characteristics and photomicrographs are provided for each Korean new record. In addition, a partial sequence of mitochondrial cytochrome c oxidase subunit 1 gene (mtCOX1) for S. simplex is presented.

• Journal of Species Research
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• 제12권1호
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• pp.90-94
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• 2023

The morphology and infraciliature of three newly recorded Aspidisca species in Korea, two collected from the eastern coast and one collected from Jeju Island, were investigated in vivo and after protargol impregnation. The three species are as follows: A. dentata Kahl, 1928, A. hexeris Quennerstedt, 1869, and A. polystyla Stein, 1859. The three species are characterized by having a "polystyla-arrangement" of frontoventral cirri: 1) A. dentata is characterized by having a broadly rotund body shape, a distinct peristomial spur, and a dorsal thorn; 2) A. hexeris is characterized by a broadly oval body shape, four projections along the left margin of body, and the single peristomial spur; and 3) A. polystyla has the broadly rotund body shape, transverse cirri each split into several parts (especially in vivo), and lacking of the peristomial spur. Among them, A. dentata and A. polystyla are poorly known and lack morphological description based on silver staining. In the present study, we provide a brief diagnosis, remarks, and photomicrographs.

• Journal of Species Research
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• 제12권1호
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• pp.95-108
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• 2023

Ciliates are unicellular eukaryotes and one of the most abundant and speciose protistan groups. However, their diversity is underestimated, and many new species are waiting for our discovery. During several field surveys conducted from 2018 to 2021 to document indigenous Korean ciliates, 10 unrecorded ciliate species were collected and investigated from freshwater, marine, and semiterrestrial habitats. The morphology of these species was studied based on observation of living and protargol-stained specimens. These species belong to five classes as follows: 1) class Heterotrichea - Peritromus faurei; 2) class Spirotrichea - Heterotachysoma dragescoi, Pseudokeronopsis parasongi, and Certesia quadrinucleata; 3) class Nassophorea - Chilodontopsis depressa; 4) class Prostomatea - Plagiocampa rouxi and Urotricha furcata; and 5) class Oligohymenophorea - Metanophrys similis, Uronema gallicum, and Protocyclidium citrullus. Also, we provide a brief diagnosis, photomicrographs, and information of the locality for each species. Further, we compare each species with the most recent description and with similar congeners.

• Animal Systematics, Evolution and Diversity
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• 제39권1호
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• pp.1-9
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• 2023

During a field survey of Korean marine ciliates, we collected three ciliate species from the eastern coastal waters of the Yellow Sea. Based on the observation of living and protargol and wet silver nitrate stained cells, the ciliates, belonging to the classes Spirotrichea and Oligohymenophorea, were identified as Cardiostomatella vermiformis (Kahl, 1928) Corliss, 1960, Parallelostrombidium paraellipticum Song et al., 2018, and Pleuronema paucisaetosum Pan et al., 2015. Both Parallelostrombidium paraellipticum and Pleuronema paucisaetosum were described only from their type localities, i.e., brackish water, suggesting that they tolerate a broad range of salinity, while Cardiostomatella is marine ciliate and seems to be cosmopolitan. These three species were reported for the first time in Korea. Brief descriptions, remarks to justify their identity and to compare the present isolates with similar taxa, and photomicrographs were provided for the three species.

• Journal of Species Research
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• 제12권2호
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• pp.115-121
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• 2023

We conducted a taxonomic study of bdelloid rotifers found from terrestrial habitats such as mosses, leaf litter and soil at four different locations in Korea. The study resulted in four new Korean records belonging to two genera in two families, Habrotrochidae and Philodinidae, of bdelloid rotifers: Habrotrocha soror Donner, 1950; H. thienemanni rubella Donner, 1951; H. valida Milne, 1916 and Philodina nitida nitida Milne, 1916. These new Korean records are rare and have very limited distributions. Habrotrocha thienemanni rubella and H. valida were not found again after their original descriptions until the present study. The present study is the third record for both H. soror and P. nitida nitida. All these four new Korean records are new to Asian fauna as well. Here, diagnostic characteristics and photomicrographs are provided for each new Korean record. In addition, a partial sequence of mitochondrial cytochrome c oxidase subunit 1 gene (mtCOX1) for P. nitida nitida is presented.

• Korean Chemical Engineering Research
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• 제46권2호
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• pp.330-339
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• 2008

본 연구에서는 비이온 계면활성제, 보조계면활성제 등의 첨가제가 AOT 계면활성제 시스템의 water-in-oil(W/O) 마이크로에멀젼을 이용한 AgCl 나노입자 제조에 미치는 영향에 관하여 살펴보았다. AOT 계면활성제, isooctane, 무기염 수용액으로 이루어진 삼성분 시스템에 NP 계열 비이온 계면활성제를 첨가한 결과, 단일상으로 존재하는 W/O 마이크로에멀젼 영역은 증가하였으며, 일반적으로 첨가한 비이온 계면활성제의 친수성이 증가할수록 단일상의 영역은 증가하였다. 또한 첨가한 비이온 계면활성제는 마이셀의 계면을 보다 유연하게 함으로써 생성된 입자의 크기는 증가하고 분포도는 넓어졌다. 한편 보조계면활성제로 알코올을 첨가하면서 상평형 실험을 수행한 결과, 알코올의 사슬 길이가 증가하거나 첨가량이 증가할수록 단일상으로 존재하는 W/O 마이크로에멀젼이 보다 좁은 영역에서 형성되었다. 상평형 실험결과에 의하여 결정된 단일상의 W/O 마이크로에멀젼 영역 내에 해당하는 조건에서 보조계면활성제의 사슬 길이와 첨가량을 변화시키면서 AgCl 나노입자 제조실험을 수행한 결과, 생성된 AgCl 입자의 특성은 보조계면활성제 첨가에 따른 마이크로에멀젼의 radius of spontaneous curvature와 필름 rigidity의 변화에 의하여 결정됨을 알 수 있었다.