• 대한환경공학회지
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• 제22권6호
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• pp.1011-1019
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• 2000

본 연구는 유입수의 농도, 수리학적 체류시간 및 F/M비와 슬러지 첨전성과의 상관관계를 새롭게 명확히 밝혀 기존에 제시된 각 처리법 즉 장기포기법, 재래식 활성슬러지법, 고율 활성슬러지법 및 수정포기법의 설계조건이 도출된 원인을 밝히고 동시에 이들 기 제시된 설계조건에 관계없이 설계가 가능함을 확인하기 위한 연구이다. 본 실험은 특히 체류시간과 미생물의 침강성을 중심으로 고찰되었는데, 이는 슬러지의 침강성이 기존 각 처리법의 운전조건을 결정하는 주인자$^{1)}$이기 때문이다. 따라서 각각의 처리법에 대해 제시된 설계범위를 벗어날 경우 슬러지는 팽화하는 것으로 알려져 있으며, 설계의 기초를 제공한 Lesperance$^{1)}$의 실험결과에서도 침강성이 확보되지 않는 부하범위가 발생하는 것으로 나타냈다. 위와 같이 일정 조건에서 슬러지가 팽화하는 원인은 Lesperance가 이전 다년간의 실패와 시도로 밝혀진 연속운전이 가능한 것으로 밝혀진 몇몇의 운전조건을 실험조건으로 채용함에 따라 각각의 체류시간에 해당하는 최적의 부하가 적용되지 않았기 때문이다. 하지만 본 실험결과 부하를 적절히 유지할 경우, F/M비 $6.3kg-BOD/kg-MLSS{\cdot}day$ 이하, HRT 0.67hr 이하의 조건에서 슬러지의 침강성이 SVI치 120 이하로 확보될 수 있음을 확인하였다. 따라서 본 연구에서는 체류시간과 그에 해당하는 최적 부하를 제시하였으며, 체류시간이 미생물의 침강성에 결정적 영향인자임을 밝히고, 아울러 본 실험결과를 근거로 이제까지 알려진 처리법에서는 적용된 바 없는 1시간 이하의 체류시간에서 고율 활성슬러지법의 적용 부하치를 수 배 능가하는 새로운 운전법 (UHR : Ultra high rate)도 가능함을 제시하였다.

• 대한수의사회지
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• 제17권1호
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• pp.45-50
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• 1981

The adult New Hampshire female chickens were phlebotomized and the blood heparinized was centrifuged. The packed cell volume was made and the hematocrit, per centage of the blood that is red cells, was reschuffled of $10\%,30\%,50\%, and 70\%$

• 약학회지
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• 제12권3_4호
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• pp.41-49
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• 1968

The optimum reaction conditions for the preparation of the precipitated calcium carbonate of an average particle size of 0.05.mu. in diameter was set in which the Box-Wilson Plan was applied. The reaction conditions are as follows; 1) concentration of milk of lime; 6.56% w/w 2) temperature; 14.24.deg. C #) velocity of carbon dioxide introducing; 1.95l/min. The crystal form was found that of calcite in X-ray diffraction analysis. The particle size was determined by the sedimentation volume measurement. The shape was identified by the elctron micro-diffraction pattern and the electron microscopic photographs.

• Food Science and Biotechnology
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• 제15권6호
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• pp.860-865
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• 2006

The quality parameters of sponge cake supplemented with soy protein concentrate (SPC) were evaluated. The addition of SPC to wheat flour increased the protein content and alkaline water retention value, but decreased the sedimentation value. Protein content had a positive correlation with the alkaline water retention value, and a negative correlation with the sedintentation value. The higher the concentration of SPC, the higher the RVA pasting temperature and the lower the viscosity. Increasing the level of SPC in flour led to a decrease in mixogram peak time, whereas peak height, width at peak, and width at 8 min progressively increased. As the amount of SPC increased in the formulation, the pH and specific gravity of cake batter increased, whereas the volume and specific volume of sponge cake decreased. The total isoflavones content in SPC increased after heat treatment. The hardness, gumminess, and chewiness increased progressively in accordance with increasing level of SPC.

• 한국작물학회지
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• 제47권1호
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• pp.21-28
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• 2002

Noodle texture parameters of Korean style wet and dry noodles and relationships between noodle quality and flour characteristics were evaluated for two years, 1997 and 1998, and at two locations, Suwon and Deokso, using Korean winter wheat cultivars and lines. No significant difference for chewiness was found between cultivars over locations. Noodles made from flours from 1997 showed significantly higher chewiness than those from 1998. Chewiness of cooked noodles showed positively significant correlations with protein content and SDS sedimentation volume and negatively significant correlations with starch peak viscosity and flour swelling volume. Korean winter wheat cultivars, except for Gobunmil, Keumkangmil Tapdongmil, Suwon 265 and Suwon 280, showed chewiness of cooked noodles similar to commercial flours used for noodle making in Korea and Japan.

• 한국작물학회지
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• 제46권5호
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• pp.367-374
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• 2001

End-use properties of six Korean waxy wheat lines and their parental plants were evaluated in this study. Korean waxy wheat lines showed unsuitable characteristics for end products, such as sticky crumb of bread, sticky cooked wet and dry noodles and small cookie diameter. Korean waxy wheat lines produced lower loaf volume and less desirable crumb grain structure of bread, and lower chewiness of cooked wet and dry noodles than their parental plants even though Korean waxy wheats were much higher in protein content and SDS-sedimentation volume than their parental plants. We observed adverse effects of high flour protein content in Korean waxy wheat lines, such as smaller cookie diameter and harder snapping force than those produced from their parental plants.

• 상하수도학회지
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• 제18권6호
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• pp.742-747
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• 2004

Solid-liquid separation of swine wastewater was conducted using bentonite as coagulant. During the separation experiment, coagulation efficiency was also investigated. To determine optimal bentonite dose, 0.1, 0.2, 0.4, 0.8, and 1.6% (w/v basis) of bentonite was dosed. Suspended solid removal efficiency was 87-98% at whole bentonite dosage. But sediment volume was increased, and settling velocity was decreased at excessive bentonite dosage. Therefore optimal bentonite dosage was evaluated around 0.2-0.4%. In the test to determine optimal pH, coagulation using bentonite was performed at pH 3, 4, 5, 6, and 7. At lower pH suspended solid removal efficiency was increased. However, sediment volume was also increased and phosphorus release was observed. Thereby optimal pH for bentonite coagulation might be appeared in the range of 6-7.

• Korean Membrane Journal
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• 제1권1호
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• pp.100-105
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• 1999

A novel system to thicken the concentrated colloidal solution from membrane water treat-ment processes was developed. A hollow-fiber microfilter(hydrophilic polyethylene nominal pore size 0.1 ${\mu}$m total surface area 0.42 m2) was installed in an acrylic housing that has an aeration port 5 cm below the membrane and a clarifier in the bottom. The concentrate was uniformly supplied from the top of the housing. Bacuum filtration caused downward flow of concentrate and as a result thickening interface. The addition of poly-aluminum chloride (PAC) resulted in rapid increase of trans-membrane pressure (TMP) and in no improvement of the filtered water turbidity and thickening process. Two types of con-centrate and concentrate turbidity had little effect on the increase of TMP and concentrate thickening. It was observed that for the same height of membrane housing membrane surface area to housing volume (A/V) ratio had significant effect on the increase of TMP. When the housing volume was increased ten times the increasing rate of TMP was three times faster as compared to the original housing. A hydraulic model successfully simulated the formation and sedimentation of thickening interface.

• Journal of Korean Society for Atmospheric Environment
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• 제20권E2호
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• pp.61-68
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• 2004

Aerosol losses in a 100L Tedlar$^{(R)}$ bag were investigated for the aerosols with number median diameter of 0.05 ${\mu}{\textrm}{m}$ and number concentration of 6.4 ${\times}$ 10$^4$ cm$^{-3}$ . Over a 1 hr period, loss of particles in the bag is apparent, and the volume decrease with time is significant. The number concentration, surface area, and volume concentration of the aerosols decreased to 34, 50, and 52% of the initial value in 30 min, respectively. This indicates that deposition to the walls was the main loss process for aerosols in the Tedlar$^{(R)}$ bag. Theoretical calculations showed that coagulations and deposition by diffusion and gravitational sedimentation would not change aerosol characteristics significantly, and the electrical force was the dominant loss process for particles in the Tedlar$^{(R)}$ bag over a 1 hr period.eriod.

• 한국작물학회지
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• 제38권1호
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• pp.8-14
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• 1993

가공 적성면에서 가장 중요한 품질요인인 단백질의 양과 질을 육종 목표로 했을 때 잡종 후기 세대에서의 선발 효과를 보기 위하여 조광 x Lancota, 수원 210호 x Atlas 66의 두 조합의 후대를 공시하여 단백질함량, 심전가, Mixogram pattern, 제빵 특성을 검토하였다. 1. F4 세대에서 선발된 고단백 집단의 단백질함량은 저단백 집단에 비해 F5 세대에서는 유의성 있게 높은 값을 보였으나 F6 에서는 유의성 있는 차이를 보이지 않았다. 2. 심전가 고단백은 경질 Group과 저단백 연질 Group간에서만 차이가 인정되었다. 3. F6 세대에서 개체별로 수확하여 단백질함량과 심전가를 분석한 결과, 분포영역은 저단백 연질, 저단백 경질, 고단백 연질, 고단백 경질 Group의 순서로 단백질 함량 및 심전가 높은 쪽으로 이동되었으며 이러한 경향은 수원 210호 x Atlas 66 조합에서 더욱 뚜렷하였다. 4. 밀가루 반죽의 특성을 나타내는 Mixogram pattern은 각 특성 Group별로 고유의 형태를 보여 선발의 효과를 볼 수 있었다. 5. F6 세대의 제빵 특성은, 수원 210호 x Atlas 66 조합은 고단백 경질 Group이 저단백 연질 Group에 비해 빵의 부피가 큰 것으로 나타났으나 조광 x Lancoa 조합은 유의성 있는 차이를 보이지 않았다.