• 제목/요약/키워드: Condition of isolation

검색결과 425건 처리시간 0.025초

조류생산잠재력조사 방법개발에 의한 육수환경의 부영양화 방지대책에 관한 연구(I) -순수분리종의 형태 및 증식특성- (A Study on Protection Plan of Eutrophication in Fresh Water Environment by Development of Methods for Algal Growth Potential test (I) -Morphology and Growth Characteristics of Isolated algae-)

  • 위인선;나철호;이종빈;주현수
    • 한국환경보건학회지
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    • 제23권1호
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    • pp.18-27
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    • 1997
  • The isolation, morphological study and growth characteristics of the algae were investigated from Lake Chuam. The isolated algae were applied the Agal Growth Potential test. The method of isolation and purification of the algae were used to Agar plating(AP), nutrient enrichment(NE), dilution(DI) and micro capillary technique(MC). Total isolated algae were 21 species. They were composed of Cyanophyceae, Dinophyceae, Bacillariophyceae, Euglenophyceae and Chlorophyceae. The numbers of algal strain by isolation technique were highest in dilution(21 species), and those of the rests were showed in order of NE > MC > AP. The sizes of isolated Selenastrum and Scenedesmus were $1.8\pm 1.4 \mu m$, $3.3\pm 0.9 \mu m$ in diameter and $6.4\pm 2.3 \mu m$, $13.6\pm 1.9 \mu m$ in length respectively. The morphology of isolated algae and NIES-collection strain was very similar each other, but the size was smaller isolated algae than that of NIES-collection. The optimum culture condition of isolated Selenastrum and Scenedesmus was about 30$\circ$C(25$\circ$C-35$\circ$C) in temperature and the maximum growth was appeared between 7,000 lux and 8,000 lux in the light intensity. The comparison of $\mu$(specific growth rate) on the concentration of nutrients such as nitrate and phosphate, isolated Selenastrum was appeared maximum it at 1.0 mg $NO_3-N/l$ but NIES-collection strain was showed 95% of maximum it at same nitrate concentration. Maximum g of isolated algae and NIES-collection strain in Scenedesmus onto nitrate concentration were very similar with the result of selenastrum. The specific growth rates of isolated algae and NIES-collection strain on the gradient concentration of phosphate were showed 0.72/day and 0.70/day at 0.02 mg $PO_4-P/l$ in Selenastrum but those of Scenedesmus were appeared 0.61/day and 0.57/day at same concentration $PO_4-P$.

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Seismic response variation of multistory base-isolated buildings applying lead rubber bearings

  • Islam, A.B.M. Saiful;Al-Kutti, Walid A.
    • Computers and Concrete
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    • 제21권5호
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    • pp.495-504
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    • 2018
  • The possibility of earthquakes in vulnerable regions indicates that efficient technique is required for seismic protection of buildings. During the recent decades, the concept is moving towards the insertion of base isolation on seismic prone buildings. So, investigation of structural behavior is a burning topic for buildings to be isolated in base level by bearing device. This study deals with the incorporation of base isolation system and focuses the changes of structural responses for different types of Lead Rubber Bearing (LRB) isolators. A number of sixteen model buildings have been simulated selecting twelve types of bearing systems as well as conventional fixed-base (FB) scheme. The superstructures of the high-rise buildings are represented by finite element assemblage adopting multi-degree of freedoms. Static and dynamic analyses are carried out for FB and base isolated (BI) buildings. The dynamic analysis in finite element package has been performed by the nonlinear time history analysis (THA) based on the site-specific seismic excitation and compared employing eminent earthquakes. The influence of the model type and the alteration in superstructure behavior of the isolated buildings have been duly assessed. The results of the 3D multistory structures show that the lateral forces, displacement, inertia and story accelerations of the superstructure of the seismic prone buildings are significantly reduced due to bearing insertion. The nonlinear dynamic analysis shows 12 to 40% lessening in base shear when LRB is incorporated leading to substantial allowance of horizontal displacement. It is revealed that the LRB isolators might be potential options to diminish the respective floor accelerations, inertia, displacements and base shear whatever the condition coincides. The isolators with lower force intercept but higher isolation period is found to be better for decreasing base shear, floor acceleration and inertia force leading to reduction of structural and non-structural damage. However, LRB with lower isolator period seems to be more effective in dropping displacement at bearing interface aimed at reducing horizontal shift of building structure.

국내 대형병원과 중·소규모 의원의 공기감염 확산 방지 대책의 비교 평가 (Comparative Evaluation of Measures against the Spread of Air-borne Infections in a Large National Hospital and Small and Medium-sized Clinics in Korea)

  • 안지원;양영권;원안나;황정하;박진철
    • 한국생활환경학회지
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    • 제25권1호
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    • pp.90-97
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    • 2018
  • The purpose of this study is to compare and analyze the air infections in middle and small hospitals with the facilities of large national hospitals that have air-borne infection isolation (AII) wards through actual condition investigation and airflow analysis simulation (CFD) and to provide basic data for prevention. The method and scope of the study are as follows. First, through literature review, data related to prevention of infection spread in domestic medical institutions were investigated. Second, we conducted a survey on the status of isolation facilities to prevent the spread of infectious diseases in large hospitals and small and medium - sized clinics in Korea. Third, airflow analysis simulation (CFD) was carried out using the isolation ward of the nationally designated inpatient ward and the data of the plane and facility system of the small clinic. As a result of the study, it is found that regulations applicable to small and medium-sized clinics are insufficient. In addition, the simulation results show that the infectious disease virus is likely to spread to other patients in the hospital.

보리(Hordeum vulgare L.)의 전분생산에 관한 연구 (Studies on the production of Starch of Barley (Hordeum vulgare L.))

  • 서호찬
    • 한국식품조리과학회지
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    • 제15권2호
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    • pp.185-190
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    • 1999
  • 보리로부터 전분분리 및 생산기술을 개발하기 위해 wet-milling, alkali 및 ethanol 처리를 병행한 전분 분리공정의 최적조건을 검토하였다. Wet-milling에서 최적 침지온도 및 시간을 검토한 결과 3$0^{\circ}C$, 12시간으로 처리하였을 때 단백질 5.7%, 전분함량이 69%를 나타내었으며 wet-milling에서 얻어진 조전분을 대상으로 100 mesh체로 처리시 전분의 백색도는 87%를 나타내었다. Alkali 처리에서의 최적조건은 0.2% NaOH로 6시간 처리하였을 때 가장 높은 단백질 제거 (0.3%)와 전분함량(93%)을 나타내었으며 10%(v/v) ethanol처리로 0.1% 조지방 함량을 나타냄으로써 잔존해 있는 조지방 성분이 제거되었음을 알 수 있었다. 상기의 최적조건에서 얻어진 전분의 성분은 단백질 0.1%, 전분함량 95%를 나타냈으며 기타의 성분의 순도 및 백색도가 시판되고 있는 옥수수전분 규격과 비교하여 볼 때 손색이 없었다.

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주요 식중독균 분리용 선택배지의 타당성 연구 (Evaluation of Selective Media for Isolation of Foodborne Bacteria)

  • 조서희;하지형;김근성;심영환;권기성;한정아;황인균;하상도;오덕환
    • 한국식품위생안전성학회지
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    • 제22권4호
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    • pp.388-394
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    • 2007
  • 본 연구는 현행 식품공전상 제시되어 있는 식중독균 분리배지의 평가를 위해 Salmonella spp., Bacillus cereus, Listeria monocytogenes, Vibrio parahaemolyticus, Staphylococcus aureus의 5가지 식중독세균용 29가지 분리 선택배지를 Broth와 Food에서 시험하였다. Food는 닭고기, 쌀, 돼지고기, 고등어를 대상으로 5가지 식중독균을 접종후 균주의 recovery를 확인하였고. Broth는 5가지 식중독세균용 29가지 분리 선택배지를 사용하였다. Broth에서는 각 세정균에 대한 분리배지들 간에 유의적인 차이가 없었으나(P<0.05), Food에서는 그 차가 크지는 않았으나, 분리선택배지간의 분리능에 통계적 유의차가 존재하였다. 식품공전에 등재된 전통적인 분리 선택배지에서 분리된 균수가 Chromogenic 배지 등 새로운 선택배지에서 분리된 균수보다 많았다. 국제적으로 등재된 배지간의 선택성의 차이가 존재하였으며, 추후 다양한 배지가 식품공전에 등재되기 위해서는 추가 연구가 필요하다.

Nicotiana africana의 엽육 원형질체로부터 식물체 재분화 (Plant Regeneration from Mesophyll Protoplast of Nicotiana africana)

  • 최상주;이승철
    • 한국연초학회지
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    • 제15권2호
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    • pp.130-136
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    • 1993
  • Protoplasts of palisade cells were aseptically isolated from leaves of Nicotiono apicona Merxm. by the one step enzymatic method. Efficiency of colony formation were depended on cell density and light condition during incubation, but an intensity of 47 ft-c during a period of 2 weeks after isolation of the protoplasts in the Nagata and Takebe's medium promoted the planting efficiency. Protoplast - derived calli of N. africana can be differentiated into shoot when cultured on Murashige and skoog's medium containing IAA(0.Smg/$\ell$) and zeatin(5.0mg/$\ell$).

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보조회로도 영전압영전류스위칭하는 DC-DC 변환기 (A Fully Soft Switched Full Bridge DC-DC converter)

  • 전성즙;조규형
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 F
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    • pp.2512-2514
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    • 1999
  • A new zero voltage and zero current switching(ZVZCS) full bridge DC-DC converter with transformer isolation is proposed for arc welding machines. The proposed DC-DC converter uses an auxiliary transformer to obtain ZCS for leading leg, which provides load current control capability even in short circuit condition. The auxiliary circuit also operates in ZVZCS mode. The power rating of the auxiliary transformer is about 10% of the main transformer. The operation is verified by experiments for 12[KW] prototype.

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수소 생성 광합성 세균 Rhodobacter sphaeroides KS 56 분리 (Isolation of Hydrogen Evolution Photosynthetic Bacteria Rhodobacter sphaeroides KS 56)

  • 이은숙;권애란
    • 한국식품영양학회지
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    • 제10권4호
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    • pp.549-552
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    • 1997
  • 혐기성 광조건의 낮은 농도의 NH4+ 존재하에서 포도당으로부터 많은 양의 수소를 생성하는 홍색 비유황 광합성 세균을 수계혐기층으로부터 분리하였다. 이 세균은 형태적, 배양적, 생리적 특성에 따라 Rhodobacter sphaeroides KS 56으로 동정되었다.

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뜬바닥층의 하중조건에 따른 경량충격음 저감량 분석 (Analysis of the Reduction of Light-weight Imapct Noise for Load Condition of Floating Floor)

  • 김명준;이성호;양재훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 추계학술대회논문집
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    • pp.356-360
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    • 2006
  • Recently, for the purpose of improving the isolation performance of impact noise, many resilient materials have been installed in a residential building. As one of the reduction method for improving the performance of light-weight impact noise, this study is focused on the load condition of floating layer over resilient material. We studied the correlation between the mass or load of the floating layer and the reduction of light-weight impact noise by experiments in reverberation chamber for testing the impact noise. The results show that the reduction of impact noise is improved by increasing the mass per unit area of floating layer until about $140kg/m^2$. But the reduction is not obvious by adding extra mass on the floating layer.

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IMPROVING HABITAT OF FORMOSAN LANDLOCKED SALMON BY DAM REMOVAL

  • Yeh, Chao-Hsien;Lien, Hui-Pang
    • Water Engineering Research
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    • 제6권4호
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    • pp.149-159
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    • 2005
  • With increasing recognition on conservation of endangered species in Taiwan, one of the major conservation projects is the habitat restoration of Formosan Landlocked Salmon which is major threatened by check dams in the channel for their blockading pathway to upstream and causing the problems of population isolation and close-blood mating. By creating an opening in the central dam body appropriately, partial removal dams can provide pathway for the fish for the better upstream channel habitat. Four check dams at Gau-Shan Creek were remodeled between April of 1999 and September of 2002 with information supported from model experiments under certain hydraulic condition of field environment. Based on the follow-up investigation, the channel morphology of observation sections is in stable condition and the total number of Formosan Landlocked Salmon in this creek increased promptly at the reach containing partial-removed dams.

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