• 한국대기환경학회지
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• 제15권4호
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• pp.475-483
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• 1999

A lab-scale test was carried out to study the reduction of electrical energy consumption in the pulsed corona discharge process for nitrogen oxides removal. The experiment was mainly focused on 1) the activation of pollution removal reactions by chemical additives and 2) the optimization of electrical circuit for the efficient energy transfer from the power supply to the corona reactor. Hydrocarbon chemical additives used in the experiment are thought to be responsible for the enhancement of the NO conversion through the chain reactions of free radicals such as, R, RCO, and RO. Electrical energy consumption per converted NO molecule has a minimum value of 17 eV when pentanol is injected. When ethylene and propylene are injected, 30 eV and 22 eV of electrical energy consumption is required for the conversion of NO molecule respectively. The ratio of the pulse forming capacitance$(C_e)$ to the reactor capacitance$(C_R)$ plays an important role in the energy transfer efficiency to the reactor. Maximum energy transfer efficiency of approximately 72% could be obtained by using the pulse forming capacitance which is 3.4 times larger than the reactor capacitance, and also the maximum NO conversion efficiency was observed with the same condition.

• The Korean Journal of Physiology and Pharmacology
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• 제2권1호
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• pp.55-62
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• 1998

${\alpha},\;{\beta}-Adrenergics$, and calcium channels were known to be related to inducing cardiac hypertrophy. Recently, it was reported that the cardiac renin-angiotensin system (RAS) was an important factor in ventricular hypertrophy. The present study was aimed to investigate the effects of ${\alpha},\;{\beta}-adrenergic$, and calcium channel blockers that might be involved in the regulation of cardiac RAS. The reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of renin gene in the perfused rat heart. Changes in angiotensin converting enzyme (ACE) activity and cyclic AMP (cAMP) content which were thought to play a role in inducing cardiac hypertrophy were measured in the perfused rat heart. The expression of renin gene was not only increased by isoproterenol with metoprolol-pretreatment but also increased by vasopressin treatment in the presence of calcium channel blocker, nifedipine or verapamil. Either prazosin alone or norepinephrine with prazosin-pretreatment significantly increased the ACE activity. However, isoproterenol with metoprolol-pretreatment significantly decreased the ACE activity. On the other hand, the ACE activity was not changed by vasopressin, nifedipine, or verapamil treatments. The content of cAMP was significantly increased by either isoproterenol or vasopressin treatment. According to these results, renin gene expression was associated with ${\beta}2$ - adrenoceptor and calcium channel. ACE activity was associated with ${\alpha}-\;and{\beta}2$ - adrenoceptor. In conclusion, ${\beta}2$ - adrenoceptor was important in cardiac renin gene expression and ACE activity and ${\alpha},\;{\beta}$ -adrenergic, and calcium channel blockers might be involved in the regulation of cardiac RAS in a complicated way.

• 대한수의학회지
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• 제39권1호
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• pp.104-110
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• 1999

Field infectious bursal disease viruses (IBDVs) were isolated from IBDV-suspected commercial chickens. The variable region in VP2 gene of six Korean IBDV isolates (K-IBDVs) and IBD vaccines was examined using the reverse transcriptase / polymerase chain reaction-restriction fragment length polymorphism (RT/PCR-RFLP) assay. With all K-IBDVs and vaccine IBDVs, a 474-bp fragment of the VP2 gene was amplified and tested with various restriction enzymes. Restriction enzymes BstNI and StyI differentiated K-IBDV isolates and IBD vaccines into four groups. Restriction enzyme profiles of K-IBDV isolates were different from them of IBD vaccines. K-IBDV isolates except for 310 isolate had specific SspI and TaqI recognition sites, which were recognized in highly virulent IBDVs, but IBD vaccines had no those sites. This study showed that RT/PCR-RFLP assay was thought to be valuable tool for differentiation of IBDVs and identification of highly virulent IBDV.

• 한국재료학회지
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• 제2권2호
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• pp.101-109
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• 1992

PET(polyethylene terephthalate)는 섬유 및 다방면의 응용분야에 사용되는 상업용 고분자로 알려져 있다. 본 논문에서는 PET를 개질하기 위해 pentanediol의 이성질체인 1,5-pentanediol(1, 5-PD)과 neopentyl glycol(NPG)를 제3 monomer로 도입시켰다. NPG를 도입시킨 경우에는 결정화 속도가 감소하고, 1,5-PD로 개질된 PET는 1,5-PD가 약 10mo1% 첨가될 때가지 결정화 속도가 서서히 증가하였다. 이러한 결과는 NPG의 branch된 methyl기가 고분자 사슬에 표면으로 확산되면서 결정화하는 것을 방해하기 때문이다.

• 대한기관식도과학회지
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• 제4권2호
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• pp.197-204
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• 1998

Human papillomavirus(HPV) is epitheliotrophic virus invading the anogenital tract and the upper aerodigestive tract HRV produces a diversity of benign and maljgnant tumors. In this study, the author determined the frequency of association of human papillomavirus(HPV) and laryngeal carcinomas and investigated the significance of HRV infection of different subtypes in the tumorigenesis of laryngeal carcinoma. Laryngeal squamous cell cancinomas from 34 patients who did not have preexisting papillomas by clinical history were retrieved from formalin-fixed, paraffin-embedded blocks and analyzed for HPV. Nineteen cases were tumors of the true vocal folds, 11 were supraglottic and 4 were transglottic. HPV detection was dane using polymerase chain reaction amplification with HPV L$_1$consensus primer. HPV type was determined by the same method using HPV-6, 11 and 16,-18 type-specific E6 primers. The results were as follows : 1) HPV DNA was detected in 7 cases among the 34 patients(20.6%). According to the type of HPV DNA HPV-11 was detected in 3 cases, HPV-16 was detected in 2 cases and HPV-6 and HPV-18 were detected in 1 case, respectively. 2) These 7 HPV-positive patients were advanced cancinoma cases. From these results, we concluded that HPV was thought to be the etiological factor of laryngeal squamous cell carcinomas.

• 한국환경복원기술학회지
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• 제21권4호
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• pp.11-23
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• 2018

The purpose of this study is to identify the ecological characteristics and biological interactions between species of the abandoned rice paddy field in mountainous areas and to suggest a management strategy for stable food chain formation and biodiversity enhancement. The study site is located in Uldae wetland of Songchu district Bukhansan National Park, site characteristics and biological habitat characteristics were identified through site survey and literature survey. With regard to physical environment, among geographical features, the Uldae Wetland and the neighborhood inside the basin was a gently sloping area($5{\sim}15^{\circ}$). And 64.0% of basin faced the north. With regard to water environment, the Uldae Wetland was wetland of rainfed paddy field depending on precipitation and the system of stream flowing into the wetland from valley. According to the results of examining flora in plant ecology, in general, they were herbaceous wetland species. 88.6% of existing plants inside the Uldae Wetland basin was a forest in the mountain. And Quercus spp. community and Pinus densiflora community accounted for 64.6% of that, and was dominant. Except for that, Salix koreensis community was distributed. The existing vegetation of Uldae Wetland inhabited wetland species and terrestrialization indicator species, and it was thought that partial terrestrialization inside the Uldae Wetland was in progress after the discontinuation of paddy cultivation, such as the expansion of Salix koreensis distribution area. In the status of appearing faunae in the Uldae Wetland with regard to wildbirds of appearing principal species, The Uldae wetland was based on a abandoned rice paddy field various wildlife, and was a wildlife feeding, spawning, and resting place. The water environment was an important factor in maintaining the wetland living creatures function, habitat of waterbirds and benthic macroinvertebrates, amphibians and odonate are spawning ground and habitat, it was affecting the vegetation ecosystem based on wetlands. In order to maintain the diversity of wildlife, it was important to maintain smooth water supply and water level. A stable food chain will be formed and the Uldae wetland biodiversity will be abundant by establishing the relationship between the species of Uldae wetland, which is abandoned rice paddy field, and the habitat environment favored by species belonging to the ecosystem stepwise linkage. The ecological characteristics of the Uldae wetlands and the relation between the species were analyzed and the environmental conditions were reflected in the planning and management plan of Uldae wetland ecology.

• 공업화학
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• 제8권4호
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• pp.617-623
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• 1997

폴리솔베이트-핵산올-물의 3성분계의 상거동에 관한 메카니즘을 조사한 것으로, 등방성인 미셀영역에서 비등방성인 모자이크 액정상을 편광현미경에 의해 관찰하였다. 액정상 및 다른 상들은 약 20~70 wt% 범위에서 관측되었으며, 이 영역에서는 보다 안정한 유화계나 분산계의 포뮬레이션에 대한 기본적인 데이터를 제공할 수 있다. 알킬기의 탄소수 증가에 따라 3상 영역이 감소한 반면에, 2상 영역이 증가되었으며 비등방성 액정상은 관찰되지 않았다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.211-212
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• 2023

Polishing tiles among porcelain tiles are more durable and aesthetic than ceramic tiles, so their demand has recently increased. In particular, since polishing tiles have a very low absorption rate, organic adhesives with chemical bonds are mainly used. However, organic adhesives have low economic efficiency and some volatile organic compounds (TVOCs). Therefore purpose of this study was to evaluate the performance of polishing tile adhesion by developing organic-inorganic adhesives, which have chemical bonds and mechanical bonds. As a result, since the amorphous chain and chemical bonds of the polymer in the tile adhesives, both tensile and shear adhesion strength were satisfied with the KS L 1592, KS L 1593, and the rate of length change itself in the thermal cycling was lower than organic adhesives. So it is thought that it is possible to replace some organic adhesives.

• 한국식품과학회지
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• 제23권5호
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• pp.633-641
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• 1991

전분의 어떤 성질이 묵 형성을 영향을 주는가를 알기위해 도토리, 메밀, 녹두 전분(묵전분)과 옥수수, 쌀, 밀 전분(비묵전분)의 이화학적, 분자구조적 성질과 전분지방질의 함량을 조사하여 겔 강도와 비교하였다. 전분의 아밀로오스 함량은 녹두, 도토리, 메밀, 밀, 옥수수, 쌀 순이었으며 겔 강도 역시 같은 순서로 나타나 이들 사이에서 가장 좋은 상관관계를 보였다(r=0.95). 묵전분의 아밀로오스의 특성을 보면 비묵전분보다 분자크기가 켰고(${\overline}D.P._{n}=1,800{\sim}1,580\;vs\;670{\sim}1,120$), 평균 가지수가 많았으나(${\overline}N.C.=2.9{\sim}5.4\;vs\;1.7{\sim}2.5$), 평균 가지 길이는 작았다(${\overline}C.L.=290{\sim}390\;vs\;390{\sim}450$). 묵전분의 아필로펙틴의 ${\overline}C.L.$은 비묵전분보다 컸으며 ($22.2{\sim}22.6\;vs\;18.9{\sim}21.3$), 전분지방질의 함량은 비묵전분보다 더 작았다($0.12{\sim}0.49\;vs\;0.68{\sim}1.26%$), 이들 분획물의 성질과 지방질함량은 겔 강도와 좋은 상관관계($r=0.76{\sim}0.84$)를 보였다. 따라서, 묵전분의 겔 형성능력은 아밀로오스 함량과 전분의 여러 특성이 종합적으로 작용해 나타내는 것으로 보인다.

• Parasites, Hosts and Diseases
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• 제35권4호
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• pp.277-282
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• 1997

만손열두조충과 북미열두조충 (Spirometra mansonoides)의 형태 차이점은 성숙편절의 자궁의 형대 가 전자근 차곡차곡 쌓인 꼴이고 후자는 알과벳 씨자 (C)형태이라는 점이다 이 비슷한 명태의 두 종 의 조충이 유전학적으로는 얼마나 차이가 있는지를 알기 위하여 중합효소연쇄반응-마디길이여러꼴 분석법(polymerase chain reaction-restriction fragment length polymorphism analysis)을 이용하여 유전 형질을 비교하였다. 충체로부터 285리넓솜 리보핵산 (285 rDNA), 사립체 cytochlmsc 산화 효소 아단위 I (mitochondrial cytochrome c oxidase subunit 1, mCOI) 및 리보솜 내부 전사된 영역 1 (ribosomal internal transcribed spacer 1, ITSI)에 대한 중합효소반응 산물을 구하였다. 이 산를은 Msp I. Hue III, Alu I, Cfo I, Rsc I의 4 염기 제한 효소로 잘라서, 전기영동하여 길과를 PAUP 3.1.1을 이용하여 분석 하였다. 285 리보솜 리보핵산과 리보솜 내부 전사된 영역 1 유진자에서는 두 충체 가 동일 한 분류가지에 묶였고 홀로서기수 (bootstrap number)는 94, 100이었다. 사립체 cytochrome c 산 화효소 아단위 1에서는 다른 분류가지에 묶였고 홀로서기수가 74이었다. 위 결과로 투 조충이 같은 조상에서 유래함과 진화 단계에서 매우 가까운 위치에 있음을 알 수 있었다.