• 제목/요약/키워드: Water storage cells

검색결과 107건 처리시간 0.025초

Effects of Fracture Intersection Characteristics on Transport in Three-Dimensional Fracture Networks

  • Park, Young-Jin;Lee, Kang-Kun
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 추계학술발표회
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    • pp.27-30
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    • 2001
  • Flow and transport at fracture intersections, and their effects on network scale transport, are investigated in three-dimensional random fracture networks. Fracture intersection mixing rules complete mixing and streamline routing are defined in terms of fluxes normal to the intersection line between two fractures. By analyzing flow statistics and particle transfer probabilities distributed along fracture intersections, it is shown that for various network structures with power law size distributions of fractures, the choice of intersection mixing rule makes comparatively little difference in the overall simulated solute migration patterns. The occurrence and effects of local flows around an intersection (local flow cells) are emphasized. Transport simulations at fracture intersections indicate that local flow circulations can arise from variability within the hydraulic head distribution along intersections, and from the internal no flow condition along fracture boundaries. These local flow cells act as an effective mechanism to enhance the nondiffusive breakthrough tailing often observed in discrete fracture networks. It is shown that such non-Fickian (anomalous) solute transport can be accounted for by considering only advective transport, in the framework of a continuous time random walk model. To clarify the effect of forest environmental changes (forest type difference and clearcut) on water storage capacity in soil and stream flow, watershed had been investigated.

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울산지역 상수원 호수 환경에 따른 식물플랑크톤 분포 (Phytoplankton Community, Pollution Sources and Water Quality of Drinking Water Lakes in Ulsan)

  • 이혜진;탁보미
    • 한국환경과학회지
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    • 제21권11호
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    • pp.1349-1360
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    • 2012
  • This study presented the phytoplankton communities of the three lakes (Sayeon, Daeam, Hoeya ) using for drinking water in the Ulsan reservoir. The water storage of the Lake Sayeon, Daeam and Hoeya were 25, 13, 21 million ton respectively and most of which were being utilized for industrial and residential purposes. The total precipitation of the Ulsan region in 2010 was 1,162 mm, decreasing 10 % from 1,275 mm of the annual. As for pollutant loads, BOD and TN discharge loads of Daeam was the highest with 3,277 kg/day, 1,931 kg/day and 90 % of them were came from non-point pollutant sources. TP discharge loads showed the highest in the lake Hoeya with 643 kg/day and 97 % of them were came from point sources as household, industry and livestock. We assessed water quality of the lake Sayeon, Daeam and Hoeya using 17 variables. The water quality assessment found that the lake Daeam met the fourth to fifth grade because of high concentration of COD, SS and chlorophyll-a. Eutrophication assessment was conducted by revised Carlson's Index (TSIm, Aizaki) and found that Lake Daeam was more eutrophicated than the other two lakes all the year through as for chlorophyll-a, transparency and the total phosphorus (TP). A total of 95~111 phytoplankton species were identified from the three lake samples. Among them, the largest number of species were Chlorophyceae with 35~51, followed by Bacillariophyceae with 36~45, Cyanophyceae with 9~11, and Cryptophyceae with 6~9 species. The total cell number of phytoplankton was the highest in February (15,254 cells/mL) with Bacillariophyceae in the lake Daeam and the seasonal succession shows that Bacillariophyceae (Stephanodiscus spp.) in the spring, Cyanophyceae (Anabaena spp.) in the summer and the autumn, Bacillariophyceae (Stephanodiscus spp.) in the winter.

소유역 지표유출의 시간적 . 공간적 재현을 위한 GIS응용모형 (GIS Application Model for Temporal and Spatial Simulation of Surface Runoff from a small watershed)

  • 정하우;김성준;최진용;김대식
    • Spatial Information Research
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    • 제3권2호
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    • pp.135-146
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    • 1995
  • 본 연구의 목적은 소유역 지표유출의 시각적.공간적 재현을 위한 GIS의 응용 및 호환 모형 GISCELWAB을 개발하는 것이다. 이 모형은 세가지의 모형으로 구성되었다. 분포형 수문모형인 격자 물수지 모형 CELWAB과 CELWAB 모형의 입력자료를 자동으로 추출하는 입력자료 추출모형GISINDATA 와 CELWAB모형의 계산결과를 도형화하여 도시하도록 구성된 출력자료처리 모형GISOUTDISP로 구성되었다. GISINDATA는 모형의 입력자료 구성에 소모되는 시간을 절약하고 자료의 객관적 정확성을 갖도록 하기 위하여 개발되었으며, GISOUTDISP는 CELWAB 모형의 결과르 도형화하고 도시하여 유역전체에 대한 유출현상을 시간적, 공간적으로 재현하는 것을 가능하게 하였다.

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수중 환경에서 고분자 전해질 연료전지(PEMFC) 공급용 수소 생산을 위한 가압 디젤 개질시스템에 관한 연구 (Study on Pressurized Diesel Reforming System for Polymer Electrolyte Membrane Fuel Cell in Underwater Environment)

  • 이광호;한광우;배중면
    • 한국군사과학기술학회지
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    • 제20권4호
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    • pp.528-535
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    • 2017
  • Fuel cells have been spotlighted in the world for being highly efficient and environmentally friendly. A hydrogen which is the fuel of fuel cell can be obtained from a number of sources. Hydrogen source for operating the polymer electrolyte membrane fuel cell(PEMFC) in the current underwater environment, such as a submarine and unmanned underwater vehicles are currently from the metal hydride cylinder. However, metal hydride has many limitations for using hydrogen carrier, such as large volume, long charging time, limited storage capacity. To solve these problems, we suggest diesel reformer for hydrogen supply source. Diesel fuel has many advantages, such as high hydrogen storage density, easy to transport and also well-infra structure. However, conventional diesel reforming system for PEMFC requires a large volume and complex CO removal system for lowering the CO level to less than 10 ppm. In addition, because the preferential oxidation(PROX) reaction is the strong exothermic reaction, cooling load is required. By changing this PROX reactor to hydrogen separation membrane, the problem from PROX reactor can be solved. This is because hydrogen separation membranes are small and permeable to pure hydrogen. In this study, we conducted the pressurized diesel reforming and water-gas shift reaction experiment for the hydrogen separation membrane application. Then, the hydrogen permeation experiments were performed using a Pd alloy membrane for the reformate gas.

레토르트파우치 조미 홍합의 제조 및 저장 중 품질 변화 (Preparation of Retort Pouched Seasoned Sea Mussel and Its Quality Stability during Storage)

  • 노윤이;윤호동;공청식;남동배;박태호;김정균
    • 수산해양교육연구
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    • 제23권4호
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    • pp.709-722
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    • 2011
  • This study was investigated to obtain basic data which can be applied to processing of retort pouched seasoned sea mussel. Shell was washed and steamed before shucking. Sea mussel meat was seasoned in boiled and mixed seasoning sauce(soy sauce 23%, monosodiun glutamate 2%, sorbitol 2%, sesame oil 1%, vinegar 2%, starch syrup 15%, water 55%) for 30 min. The seasoned sea mussel was vacuum packed in plastic film bag and sterilized for various Fo values(Fo 7~13 min.) in a hot water circulation system retort at $121^{\circ}C$. The chemical composition such as pH, VBN, amino-N, total amino acid, free amino acid, color value (L, a, b), texture profile, TBA value, mineral, sensory evaluation and viable cells count of the retort pouched seasoned sea mussels sterilized with various conditions(Fo 7~13 min.) were measured. The same experimental items were also measured during storage. There was no remarkable difference between sterilization conditions and sensual characteristics. The results showed that the product sterilized at Fo 7 min. was the most desirable because this condition is most economical.

양파추출물의 갈변 및 매운맛 억제기술 (Browning and Pungent Taste Reduction Techniques in Onion Extract)

  • 김희선;김명환
    • 산업식품공학
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    • 제13권4호
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    • pp.360-364
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    • 2009
  • 추출방법과 $\beta$-cyclodextrin, soluble starch 및 calcium chloride 혼합용액(MIX) 처리가 양파추출물의 색도에 미치는 영향을 분석한 결과 추출방법에 관계없이 처리구가 대 조구보다 L(명도) 값은 크게 나타났으며 a(적색도)와 b(황색도)는 작은 값을 나타내었다. 갈변도는 100${^{\circ}C}$ 열수추출의 경우 대조구와 처리구의 O.D.값은 각각 0.296 과 0.093 으로서 처리구가 대조구의 약 31%의 O.D.값을 보였다. 열수추출과 초음파추출 모두 대조구가 처리구보다 높은 pyruvic acid 함량을 나타내었다. 관능검사의 갈변정도와 매운맛 강도에서는 대조구가 처리구에 비하여 높은 값을 보였다. 양파추출물의 총균수와 대장균군수는 저장기간이 길어짐에 따라서 계속적으로 증가를 보였고 저장기간 내내 처리구가 대조구보다 매우 적은 수치를 나타내었다.

High Alloying Degree of Carbon Supported Pt-Ru Alloy Nanoparticles Applying Anhydrous Ethanol as a Solvent

  • Choi, Kwang-Hyun;Lee, Kug-Seung;Jeon, Tae-Yeol;Park, Hee-Young;Jung, Nam-Gee;Chung, Young-Hoon;Sung, Yung-Eun
    • Journal of Electrochemical Science and Technology
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    • 제1권1호
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    • pp.19-24
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    • 2010
  • Alloying degree is an important structural factor of PtRu catalysts for direct methanol fuel cells (DMFC). In this work, carbon supported PtRu catalysts were synthesized by reduction method using anhydrous ethanol as a solvent and $NaBH_4$ as a reducing agent. Using anhydrous ethanol as a solvent resulted in high alloying degree and good dispersion. The morphological structure and crystallanity of synthesized catalysts were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HR-TEM). CO stripping and methanol oxidation reaction were measured. Due to high alloying degree catalyst prepared in anhydrous ethanol, exhibited low onset potential for methanol oxidation and negative peak shift of CO oxidation than commercial sample. Consequently, samples, applying ethanol as a solvent, exhibited not only enhanced CO oxidation, but also increased methanol oxidation reaction (MOR) activity compared with commercial PtRu/C (40 wt%, E-tek) and 40 wt% PtRu/C prepared in water solution.

실리카 분말과 젤 여과 크로마토그래피를 이용한 효과적인 융합 페리틴의 정제 (Efficient Purification Of Fused Ferritin[$F_{H}+F_{L}$] using Silica Powder and Gel Filtration Chromatography)

  • 허윤석;김인호
    • KSBB Journal
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    • 제17권4호
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    • pp.365-369
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    • 2002
  • 수용성 형태로 존재하는 융합 페리틴을 정제함에 있어서 실리카 분말을 이용한 전처리 공정은 전체 정제 공정효율 증가에 기여하였다. 전처리 공정을 통해 정제된 융합 페리틴의 순도를 높이기 위해 젤 여과 크로마토그래피를 통해 보다 정제된 응합 페리틴을 얻을 수 있었다. 이렇게 정제된 융합 페리틴의 철분결합능력을 분석해본결과 320 moles $F_{H}+F_{L}$ mole로 활성이 우수함을 알 수 있었으며, 분자량 분석을 통해 융합페리틴(40 k dalton)은 trimer와 monomer형태로 존재함을 확인할 수 있었다

두부의 저장에 미치는 응고제와 침지액의 효과 (Effects of Coagulants and Soaking Solutions of Tofu (Soybean Curd) on Extending its Shelf Life)

  • 이갑상;김동한;백승화;전승호
    • 한국식품과학회지
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    • 제22권2호
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    • pp.116-122
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    • 1990
  • 두부의 응고제와 침지액을 달리하여 저장 중 침지액의 미생물상과 이화학적인 변화를 검토하였다. 두부는 HAc로 응고시키는 것이 $CaCl_2$보다 저장성 향성에 효과적이었고 $CaCl_2$로 제조한 두부는 $30^{\circ}C$에서 15-17시간만에 부패가 시작되어 세균수는 $10^7cells/ml$에 달하였다. 침지액은 0.1% HAc용액이 3% NaCl 용액이나 0.1% K-sorbate용액보다 두부저장에 효과적이었다. 침지액의 탁도는 두부가 부패함에 따라 비례적으로 증가하였으며 3% NaCl이나 0.1% K-sorbate 용액에 침지할 때 탁도의 증가는 심하였다. 두부의 부패가 진행될수록 침지액의 적정산도와 아미노태 질소량은 증가하였으며 pH는 1-2일 후에 증가하였다.

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큰느타리버섯 균사체로 제조한 발효두부 추출물의 면역 활성 (Immuno-Activities of Extracts of Tofu Fermented with Pleurotus eryngii Mycelia)

  • 이상원;강종우;김재용;박경욱;박석규;주옥수;이성태;서권일
    • 한국식품영양과학회지
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    • 제39권1호
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    • pp.25-30
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    • 2010
  • 두부의 기능성 및 저장성을 향상시킬 목적으로 큰느타리버섯 균사체를 이용한 발효두부를 제조하여 물과 메탄올로 추출하여 면역세포 활성에 미치는 효과를 조사하였다. 큰느타리버섯 균사체를 배양하기 위한 최적 배지는 PD broth 배지인 것을 확인하였으며, 큰타리버섯 균사체를 이용한 두부의 최적 발효기간은 7일 정도가 적당하였다. 큰느타리버섯 균사체를 이용하여 발효한 두부의 물 및 메탄올추출물은 $0.01 {\mu}g/mL$ 농도 이상에서 비장세포의 증식을 유도하였으며, 이들 추출물은 IL-6, IFN-$\gamma$ 분비를 유도하는 것으로 나타났다. 발효두부 물 추출물은 대조군에 비해 대식세포의 일산화질소 생산을 $1 {\mu}g/mL$ 농도 이상에서 유의적으로 증가시키는 것을 알 수 있었으며, 메탄올 추출물은 $10 {\mu}g/mL$ 농도 이상에서 그 생산을 증가시켰다. 발효두부 추출물들은 대식세포가 분비하는 IL-6, TNF-$\alpha$, IL-1$\beta$ 및 GM-CSF 분비량을 유의하게 증가시켰다. 따라서 큰느타리버섯 균사체로 발효한 두부는 기능성 두부로 개발이 가능하리라 생각된다.