• 한국식품과학회지
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• 제25권6호
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• pp.787-793
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• 1993

나뭇잎, 토양, 볏짚, 깻묵, 우분, 메주로부터 지질을 다량 생산하는 곰팡이를 얻기위하여 A. sydowi SW 4-1을 분리 종정하였다. 이 균의 지질 생산 최적조건과 이 균이 생산한 지질의 화학적 특성을 연구한 결과 A. sydowi SW 4-1의 최적 배양조건인 27%의 sucrose가 함유된 배양기에 질소원은 urea로 하고 C : N 비율이 105로 17일간, $27^{\circ}C$에서 배양했을 때 생산된 균체량은 49.9g/l이었고, 지질 함유율은 건물 중량당 42.4%이었다. 최적조건에서 생산된 A. sydowi SW 4-1의 자방산 조성은 palmitic acid 27.0%, stearic acid 13.5%, oleic acid 14.9%, linoleic acid 42.3%로 linoleic acid의 함유율이 가장 높았다.

• 대한수의학회지
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• 제27권2호
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• pp.245-251
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• 1987

A total of 145 strains of thermophilic Campylobacter spp. isolated from the fecal specimens of 108 cattle, 120 pigs and 104 chickens. The isolation rates of Campylobacter jejuni from cattle, pigs and chickens were 36.1%, 38.3% and 28.8%, respectively. In the biotyping of 115 strains of C. jejuni, 49.6% were belonged to biotype I, 33.9% biotype II, 10.4% biotype IV and 6.1 % biotype III. Twenty-eight strains of C. coli were 78.6% of biotype I, 21.4% biotype II. Two strains of C. laridis belonged to biotype I and II. One hundred of 105 C. jejuni cultures were typable serologically and represented 13 serogroups Serotype 4, 5, 26, 27 and 36 were encountered most frequently. Eighteen of 23 C. coli cultures were typable serologically and represented 6 serogroups. Serotype 8, 20, 21 and 31 were encountered most frequently. In the comparison of frequency of serotype between animal species, serotypes 4, 30, 5, 26 and 27 were encountered relatively common in the cattle source isolates, serotypes 26 and 36 in the pigs, and 36 and 17 in the chickens. The serotypes of C. coli encountered most frequently were serotype 8 and 31.

• 한국잡초학회지
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• 제14권4호
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• pp.298-313
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• 1994

잔효기간이 긴 것으로 알려진 토양처리형 제초제 napropamide를 밭토양중 여러 환경조전하에 처리하여 이 약제의 토양중 분해성을 검토하고, 이 제초제가 토양미생물 상변화에 끼치는 영향에 대하여 실험을 실시한 결과는 다음과 같다. 살균토양과 비살균토양에서의 napropamide의 분해반감기는 각각 28.3, 14.6 일이었다. 수분함량의 차이에 따른 napropamide의 분해 속도는 60% > 80% ${\geq}$ 40% 순이였으며 napropamide의 처리와 무처리간의 미생물 발생수는 유의성이 없었고, 처리구내의 60% 수분함량구가 40% 수분함량구에서보다 세균수와 총균수가 많았다. pH의 차이에 따른 napropamide의 분해속도는 pH가 낮을수록 빨랐으며, napropamide처리구내 총균수는 pH5.5에서 경시적으로 증가하는 경향을 보였다. Napropamide의 분해속도는 $27^{\circ}C$ > $37^{\circ}C$ > $17^{\circ}C$의 순으로 빨랐으며, 각 온도에 있어서 napropamide 무처리구와 처리구간의 미생물수는 $17^{\circ}C$에선 방선균이, $27^{\circ}C$, $37^{\circ}C$에선 세균이 무처리구보다 처리구에서 증가됨을 알 수 있었다. Napropamide의 반감기는 10ppm과 20ppm처리에서 각각 16.6일과 21.1일이었고, 미생물 발생수는 20ppm처리구에서보다 10ppm처리구에서 많았다. 식양토와 미사질 양토에서 napropamide의 반감기는 27.7일, 17일이었으며, 처리구와 무처리구간의 미생물 발생수는 차이가 없었다. 포장 및 실내조건에서의 napropamide의 반감기는 각각 5.4일과 19.1일로 포장에서가 실내에서 보다 분해속도가 3.5배 빨랐다.

• 환경생물
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• 제26권4호
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• pp.323-329
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• 2008

비단가리비 치패의 수온(24, 27, 30$^{\circ}C$)과 염분(24, 27, 30%o)에 따른 먹이 섭취 활동(여수율과 소화율)및 체조성의 변화를 조사한 결과 수온과 염분 변화에 의하여 일간 먹이량, 여수율, 소화율 및 체성분이 영향을 받는 것으로 나타났다. 수온과 염분에 따른 비단가리비의 여수율과 소화율은 수온 24$^{\circ}C$의 30%o실험구에서 각각 8.88 L h$^{-1}$ g$^{-1}$과 25.42$\times$10$^7$ cells h$^{-1}$ g$^{-1}$로 가장 높게 나타났으며, 30$^{\circ}C$의 24%o에서 여수율과 소화율이 0.15 L h$^{-1}$ g$^{-1}$와 0.73$\times$10$^7$ cells h$^{-1}$ g$^{-1}$로 가장 낮은 값을 보였다. 비단가리비 치패의 체조성 성분은 고수은인 30$^{\circ}C$ 실험구와 저염분인 24%o 실험구에서는 다른 실첨구에 비하여 조단백질이나 조지방 함량이 적은 것으로 나타났다. 본 실험 결과 여름철 고수온과 저염분이 바지락의 대량 폐사 원인으로 작용하며 안정적인 생산을 방해하는 요인임을 알 수 있었다.

• Carbon letters
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• 제13권1호
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• pp.39-43
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• 2012

The size and the physical properties of graphene oxide sheets were controlled by changing the oxidation temperature of graphite. Graphite oxide (GO) samples were prepared at different oxidation temperatures of $20^{\circ}C$, $27^{\circ}C$ and $35^{\circ}C$ using a modified Hummers' method. The carbon-to-oxygen (C/O) ratio and the average size of the GO sheets varied according to the oxidation temperature: 1.26 and 12.4 ${\mu}m$ at $20^{\circ}C$, 1.24 and 10.5 ${\mu}m$ at $27^{\circ}C$, and 1.18 and 8.5 ${\mu}m$ at $35^{\circ}C$. This indicates that the C/O ratio and the average size of the graphene oxide sheets respectively increase as the oxidation temperature decreases. Moreover, it was observed that the surface charge and optical properties of the graphene oxide sheets could be tuned by changing the temperature. This study demonstrates the tunability of the physical properties of graphene oxide sheets and shows that the properties depend on the functional groups generated during the oxidation process.

• Applied Biological Chemistry
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• 제34권2호
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• pp.142-148
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• 1991

개화후 15일된 대두미숙종자를 배양하였을 때 callus의 형성에 적당한 온도는 $24{\sim}27^{\circ}C$였으며, NAA를 생장조절제로 사용하였을 때 embryogenic callus(EC)가 많이 형성되었다. 또한 EC를 계대배양하였을 때 BA 2mg/1 사용한 배지에서는 shoot가, IAA 2mg/1 사용한 배지에서는 root가 많이 형성되었으나, BA 2mg/1 IAA 2mg/1를 동시에 사용한 배지에서는 callus의 형성만 왕성할 뿐, 기관분화의 기미는 보이지 않았다. 배양체에 함유되어 있는 total lipid는 온도가 낮은 배양조건일수록 많았으며, callus의 생육이 왕성한 $24{\sim}27^{\circ}C$에서 glycolipid, phospholipid, free sterol의 함량이 다소 많아졌으며, embryogenic structure가 많이 생겨날 때에는 free sterol의 함량이 많았다. 배양체의 지방산 조성은 EC에서 불포화 지방산의 함량이 많았으며, 불포화도는 0.837이었다. 또한 sterol조성에서도 EC에서 cholesterol의 함량이 다른 배양체에서보다 현저히 높았다.

• 한국축산식품학회지
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• 제27권1호
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• pp.102-109
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• 2007

Lactobacillus salivarius subsp. salivarius CNU27 possessed a high level of ${\alpha}$-galactosidase activity. Purified ${\alpha}$-galactosidase was obtained after sonication of harvested cell pellet followed by DEAE-Sephadex A-50 and Mono Q anion exchange chromatography. The specific activity of the purified enzyme was 8,994 units/mg protein which is 17.09 times higher than that in crude extract. The native enzyme was a monomer with a molecular mass of 56,397.1 dalton. The optimum temperature and pH for the enzyme were $40^{\circ}C$ and 6.0, respectively. The enzyme was stable between 25 and $50^{\circ}C$. However, ${\alpha}$-galactosidase activity was lost rapidly below pH 4.5 and above pH 8.5. The enzyme activity decreased to 6.73% and 4.30% of the original activity by addition of $Cu^{2+}$ and $Hg^{2+}$, respectively. Other metal compounds did not affect the enzyme activity significantly. The enzyme liberated galactose from melibiose, raffinose, and stachyose. The rate of substrates hydrolysis was measured by HPLC. Raffinose, stachyose and melibiose were completely decomposed after 24 hr at $40^{\circ}C$.

• Mycobiology
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• 제42권1호
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• pp.27-33
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• 2014

From April 2009 to October 2011, we surveyed the higher fungi in the Byeonsanbando National Park, Korea. In total, we identified 2 kingdoms, 3 divisions, 7 classes, 22 orders, 63 families, 149 genera, and 313 species (including 6 undocumented taxa: 2 families, 2 genera, and 2 species). Seventeen 17 orders, 49 families, 128 genera, and 286 species belonged to Basidiomycota; 7 orders, 9 families, 15 genera, and 21 species were of Ascomycota; and 4 orders, 5 families, 6 genera, and 6 species of primordial fungi. Among the Basidiomycota, Agaricomycetes were represented by 47 families, 126 genera, and 282 species. The most common fungi were Boletaceae (33 species), followed by Russulaceae (30), Agaricaceae (27), and Amanitaceae (24). Various species of most of the higher fungi occurred during periods with average temperatures of $23{\sim}24.9^{\circ}C$, maximum temperatures of $28{\sim}31.9^{\circ}C$, minimum temperatures of $22{\sim}22.9^{\circ}C$, > 82% relative humidity, and > 200 mm precipitation.

• Animal Systematics, Evolution and Diversity
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• 제27권1호
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• pp.47-52
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• 2011

Creeping ctenophores, Coeloplana species, were collected by SCUBA divers throughout the year (November 2006 to June 2010) from the branches and polyp masses of encrusting dendronephthyas at a depth of 20-32m off Munseom Island (Seogwipo-si, Jeju-do, Korea). A single individual of a newly recorded species in Korea, Coeloplana bocki Komai, 1920, was collected together with C. anthostella from the same location on 16 August 2009. A large number of individuals of each species were subsequently collected from the host Dendronephthya aff. dendritica on 20 June 2010. C. bocki can be distinguished from C. anthostella Song and Hwang, 2010 and C. komaii Utinomi, 1963 by its unique blue and orange colored stripes, and/or the branching and anastomosing milky-white stripes encircling the aboral sense organ towards the margin. The detailed morphology and molecular sequence information (nuclear 18S rDNA, internal transcribed spacer 1, and mitochondrial cox1 gene sequences) for C. bocki is provided, and C. bocki and C. anthostella are compared.

• Bulletin of the Korean Chemical Society
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• 제27권6호
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• pp.869-874
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• 2006

We have carried out the Glaser oxidative coupling polymerizations of diethynyldiphenylsilane, diethynylmethylphenylsilane,diethynylmethyloctylsilane, and 1,2-diethynyl-1,1,2,2-tetramethyldisilane to afford polycarbosilanes containing diethynyl and organosilane groups in the main chain, such as poly(diethynyldiphenylsilane), poly(diethynylmethylphenylsilane), poly(diethynylmethyloctylsilane), and poly(1,2-diethynyl-1,1,2,2-tetramethyldisilane), respectively. These obtained materials are almost insoluble in common organic solvents such as $CHCl_3$ and THF probably due to the presence of a rigid rod diacetylene group along the polymer main chain. Therefore, the polymers were characterized using several spectroscopic methods in solid state. FTIR spectra of all the polymeric materials show that the characteristic $C \equiv C$ stretching frequencies appear at 2147-2154 $cm ^{-1}$, in particular. The polymers in the solid state exhibit that the strong maximum excitation peaks appear at 260-283 nm and the strong maximum fluorescence emission bands at 367-412 nm, especially. Thermogravimetric analysis of the materials shows that about 55-68% of the initial polymer weights remain at 400 ${^{\circ}C}$ in nitrogen.