• Title/Summary/Keyword: Filtration time

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Effects of Bojungikgi-tang on Trimellitic Anhydride-induced Contact Hypersensitivity in BALB/c Mice (보중익기탕(補中益氣湯)이 접촉성 과민반응에 미치는 영향(影響))

  • Park, Yang-Gu;Jung, Myung;Bok, Young-Ok;Lee, Jin-Ho;Kang, Suk-Hoon;Lim, Kyu-Sang;Yun, Young-Gab
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.29 no.1
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    • pp.16-32
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    • 2016
  • Objective : The water extract of Bojungikgi-tang (BTE) composed with Ginseng Radix, Astragali Radix, Angelicae gigantis Radix, Atractylodes Rhizoma alba, Aurantii nobilis Pericarpium, Glycyrrhizae Radix, Cimicifuga Rhizoma, and Bupleuri Radix and it has been traditionally used for chronic diseases or weakness after illness in oriental countries. However, little is known about the effects of aqueous extract of BTE on trimellitic anhydride (TMA)-induced contact hypersensitivity (CHS). Therefore, the aim of this study was to investigate the effects of BTE on TMA-induced CHS in BALB/c mice.Methods : In this study, the extract of BTE was prepared by extracting with distilled water at 100℃ for 2.5 h. The extract was freeze-dried following filtration through 0.45 μm filter. Mice were orally administrated with or without BTE extract of different doses (25-200 ㎎/㎏/day) for 28 days. During the challenge period, mice were externally applied with different doses of BTE extract one time per day 30 min before TMA treatment. I examined the effects of BTE on the serum levels of IgE, IgG1, IgG2a, and IgG2b, nitric oxide (NO) and prostaglandin E2 (PGE2) production in isolated peritoneal macrophages, Th2 cytokine production in isolated spleen cells, ear swelling responses, and the leukocyte infiltration induced by TMA.Results : The orally and externally administration of BTE dose-dependently reduced the serum levels of hapten-specific immunoglobulin E (IgE), IgG1 titer, and PGE2 production as well as ear swelling responses and leukocyte infiltration in TMA-induced BALB/c mice. The levels of NO and PGE2 production from peritoneal macrophages stimulated with TMA-BSA were markedly suppressed by pretreatment with BTE in a concentration dependent manner. Furthermore, the levels of Th2 cytokines (IL-4, IL-5, IL-13) production from spleen cells stimulated with ConA were markedly suppressed by BTE treatment in a concentration dependent manner.Conclusions : These results suggest that BTE treatment suppresses chronic contact hypersensitivity, and it can be assumed that the suppression of ear swelling, serum IgE, NO and PGE2 levels, leukocyte infiltration, and Th2 cytokines in an animal model. Therefore, these properties may contribute to the strong anti-CHS response effect of BTE.

Pre-treatment of River Water Using Biological Aerated Filtration (호기성 생물여과 공정을 이용한 하천수 전처리)

  • Choi, Dong-Ho;Choi, Hyung-Joo;Bae, Woo-Keun
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.3
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    • pp.276-285
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    • 2006
  • When polluted stream water was treated with biological aerated filter(BAF) in pilot plant, all operation with 90, 60, 45 and 30 min of EBCT at fixed $0.1m^3air/m^2min$ of aeration showed 80% or higher treatment efficiency of particle materials(SS, turbidity and Chl.-a) and 85% or higher efficiency of ammonia nitrogen removal. It was thought that, in case of BOD, biological stability may sufficiently be assured with BAF because grade III or IV inflow water was changed to grade I for outflow water. In case of $COD_{Mn}$, about 60% of removal efficiency was found. When the mechanism of the result was investigated, about 30% of COD materials was produced by algae clogged in the reactor. There was almost no biological decomposition because specific substrate utilization rate of algogenic organic materials were $0.0245mg{\cdot}COD_{Mn}/mg{\cdot}VSS{\cdot}day$, thus partial backwashing(washing the media in 1 m upper of the reactor once a day) was required. It is thought that elevation of removal rate about 10% of $COD_{Mn}$ and 5.5% of $BOD_5$ could be obtained with partial backwashing resulting in assurance of biologically more stable raw water and that saving backwashing water may be significant.

Fate and Transport of Viruses in Soil and Groundwater Environments (토양.지하수 환경에서 바이러스의 거동)

  • Park, Jeong-Ahn;Yoon, Seo-Young;Kim, Song-Bae
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.7
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    • pp.504-515
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    • 2012
  • Groundwater is widely used as drinking water supplies around the world. However, microbial contamination of groundwater is a serious environmental problem that degrades drinking water quality and poses a great threat to human health. Among the pathogenic microorganisms such as viruses, bacteria, and protozoa, viruses are not readily removed during transport through soils, having high mobility in groundwater environment due to their smaller size compared to bacteria and protozoa. Studies regarding the fate and transport of viruses in soils and aquifers are necessary to determine the vulnerability of groundwater to microbial contamination and to secure safe drinking water sources. Also, these studies provide important information to establish the regulations and policies related to public health. This review paper presented the field and laboratory studies conducted for the fate and transport of viruses in subsurface environments. Also, the paper provided the factors affecting the fate and transport of viruses, the characteristics of bacteriophages used for virus studies, and virus transport model/colloid filtration theory. Based on this review work, future researches should be performed actively to set up the viral protection zone for the protection of groundwater from viral contamination sources. Especially, the researches should be focused on the development of mathematical models to calculate the setback distance and travel time for the viral protection zone along with the accumulation of information related to the model parameters.

A study of the Mori Radicis Cortex pre-treatment on transient ischemic brain injury in mice (상백피(桑白皮) 메탄올 추출물 전처치가 일과성 허혈에 의한 생쥐의 뇌 손상에 미치는 영향)

  • Chung, Byung-Woo;Lim, Jae-Yu;Lee, Se-Eun;Lee, Byoungho;Lim, Sehyun;Lim, Chiyeon;Cho, Suin
    • The Korea Journal of Herbology
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    • v.32 no.1
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    • pp.25-31
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    • 2017
  • Objectives : Mori Radicis Cortex (MRC), the root epidermis of Morus alba L., has been traditionally used to treat lung-related diseases in Korean Medicine. The common of MRC is Mulberry bark Morus bark, and it's pharmaceutical properties and taste are known as sweet and cold, and it promotes urination and reduce edema by reducing heat from the lungs and soothe asthma. In the present study, anti-apoptotic mechanism of MRC in middle cerebral artery occlusion (MCAO) model in mice. Methods : Two-hundred grams of MRC was extracted with methanol at room temperature for 5 days, and this was repeated one time. After filtration, the methanol was removed using vacuum evaporator, then stored at $-20^{\circ}C$ until use. C57BL/6 male mice were housed in an environment with controlled humidity, temperature, and light cycle. In order to determine beneficial effects of MRC on ischemia induced brain damage, infarct volume, neurological deficit scores, activities of several apoptosis-related proteins such as caspase-8, -9, Bcl-xL in MCAO-induced brains of mice were analyzed. Mice in MRC-treated groups were orally administered 30, 100, or 300 mg/kg of body weight for three consecutive days before commencing the MCAO procedure. Results : Pre-treatment of MRC significantly reduced infarct volume in MCAO subjected mice applied with 300 mg/kg of MRC methanol extract, and MRC effectively inhibited Bcl-xL reduction and caspase-9 activation caused by MCAO-induced brain damage. Conclusions : MRC showed neuro-protective effects by regulating apoptosis-related protein signals, and it can be a potential candidate for the therapy of ischemia-induced brain damage.

A Pilot Study for Microfiltration of Alcohol Stillage Condensate and Permeate Recycle to Fermentation Broth (알코홀 증류폐액의 Pilot Scale 정밀여과와 여과액의 발효 재활용에 대한 연구)

  • 김영범;이기세;남궁견;김종현
    • KSBB Journal
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    • v.16 no.4
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    • pp.403-408
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    • 2001
  • Distillation condensate generated from downstream processing of microbial alcohol fermentation imposes a serious burden to biological wastewater treatment or anaerobic digestion due to its high contents of SS (suspended solids) and TN (total nitrogen), A pilot scale microfiltration of the stillage condensate with a stainless steel SCEPTER membrane of 0.1 ${\mu}$m pore size was carried out to remove SS which was mostly composed of microbial cell residue. A stable permeate flux was achieved when the decanter effluent containing 0.7% of SS was filtered under the conditions of X10 VCR (volume concentration ratio), 2.5 bar of TMP (transmembrane pressure), and 60$^{\circ}C$. When stillage condensate with 2.6% SS was treated directly with microfiltration, VCR below X3 was recommended for a long duration of filtration. The permeate and retentate obtained from microfiltration were recycled to make-up medium of fermentation. Adding permeate or retentate up to 30% of fermentation volume showed no distinguished undesirable influence during the course of alcohol fermentation. Although only slight improvements in the final amount of CO$_2$ evolution and alcohol content were observed, fermentation rate increased so that the required time to reach 450 L/ton of CO$_2$ evolution was shortened to 72% of that with normal media.

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Flux Decline Behavior in Cross-flow Microfiltration of Inorganic Colloidal Suspensions (무기 콜로이드 현탁액의 십자류 정밀여과에 의한 투과유속의 감소거동)

  • Nam Suk-Tae;Han Myeong-Jin
    • Membrane Journal
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    • v.15 no.4
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    • pp.338-348
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    • 2005
  • The permeate flux decline on microfiltration capillary membrane operation was investigated with inorganic colloidal solutions. The permeate flux of the alumina solution is two times higher in average than that of the bentonite solution. The flux decline with increase in operation time was less in the alumina solution than in the bentonite solution. The rate of initial flux decline until 10 min was higher on the bentonite solution over the alumina solution. The decline in permeate flux was due to both the cake formation and the pore blocking. The latter effect was higher in the operation of the bentonite solution. In comparing the ratio of each fouling component to the total fouling fur the $1.0\;kg_f/cm^2$ TMP condition, complete blocking was $9.35\%$, standard blocking was about $6.82\%$ and cake filtration was $83.83\%$, respectively. With the increase in cross flow velocity, the permeate flux increased by $6.0\%$ for the alumina solution and by 14.0 for the bentonite solution. With the increase in average pore size fromm $0.24\;{\mu}m\;to\;0.34\;{\mu}m$, the permeate flux increases 1.61 times for the alumina solution and 1.76 times far the bentonite solution.

Experimental Study on Electrokinetic Streaming Potential in Micropore Channels of Hollw-Fiber Based on General Helmholtz-Smoluchowski's Principle (일반적 Helmholtz-Smoluchowski 원리에 따른 중공사 미세기공 채널에서의 계면동전기 흐름전위에 관한 실험연구)

  • 전명석;조홍일
    • Membrane Journal
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    • v.12 no.1
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    • pp.41-50
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    • 2002
  • The streaming potential generated by the electrokinetic flow within electric double layer of charged microchannel is applied to determine the zeta potential of hollow-fiber membrane pore by using the general Helmholtz-Smoluchowski equation. The streaming potential is know to provide a useful real-time information on the surface property and the interaction between pore and particles in actual situations and physicochemical conditions. The influence of physicochemical parameters upon the filtration with hollow-fibers has been examined with an in-situ and simultaneously monitoring the streaming potential as well as permeate flux. In particular, the present study examined an experimental method to identify the effect of cake layer which can vary according to the axial position of a hollow-fiber and the progress of membrane fouling by measuring the position-dependent streaming potential. As the latex concentration increases, the permeate flux decreased but the streaming potential increased. The growth of cake layer has been mire developed with increasing latex concentration, however, the effect of surface charges of latexes deposited on the membrane surface leads to increase the streaming potential. With increasing ionic concentration of KCI, both the permeate flux and the streaming potential decrease. The increase of ionic concentration provides a compact cake layer due to the shrinkage of Debye length and the decreased streaming potential results from the weakened ionic flows owing to a thin diffusive double layer.

Effect of Periodic $N_2$-back-flushing in Paper wastewater Treatment using Carbon Ceramic Ultrafiltration and Microfiltration Membranes (탄소계 세라믹 한외 및 정밀 여과막으로 제지폐수 처리시 주기적 질소 역세척의 효과)

  • 황현정;박진용
    • Membrane Journal
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    • v.12 no.1
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    • pp.8-20
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    • 2002
  • In this study using $N_2$-back flushing, which wwas not the general back-flushing method of membranes, the discharged wastewater from a paper plant was filtrated by 4 kinds of tubular carbon ceramic ultrafiltration membranes. We could in vestigate effects of $N_2$-back flushing period, transmembrane pressure (TMP)and flow rate and find optimal operating conditions. The $N_2$-back flushing time (BT) was fixed at 40 sec, filtration times (FT) were changed in 4~32 min, TNP in $1.0~3.0kg_f/cm^2$ the flow celocities in 0.53~1.09cm/s. The optimal conditions were discussed in the viewpoints of dimensionless permeate flux ($J/J_0$), toal permeate volume ($V_T$) and resistance of membrane fouling ($R_f$). Optimal back-flushing period was BT/FT=0.167 (FT=8 min ), in which more $V_T$ was obtained than that in BT/FT=0.083 (FT=4 min) which was the most friquent back-flushing condition. Then rising TMP should increase the driving force, and more $V_T$ could be accumulated. And rising flow rate should decrease membrane fouling increase permeate flux, and more $V_T$could be produced. Average rejection rates of pollutants were higher than 95% for turbidity and 45~83% for $COD_{Cr}$, but rejection rates of total dissolved solid (TDS) were lower than 10%.

Transmembrane Pressures with Respect to Backwashing and Sinusoidal Flux Continuous Operation Modes for the Submerged Hollow Fiber Membrane in the Activated Sludge Solution (활성슬러지 수용액 내 침지식 중공사막의 역세척 및 사인파형 연속투과 운전방식에 따른 막간차압)

  • Jeong, Doin;Jung, Seung Hee;Lee, Sohl;Chung, Kun Yong
    • Membrane Journal
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    • v.25 no.6
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    • pp.524-529
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    • 2015
  • In this study transmembrane pressure (TMP) was measured with respect to operational time by applying the sinusoidal flux continuous operation (SFCO) for the hollow fiber membrane. The hollow fiber module which has $100cm^2$ of effective area and $0.45{\mu}m$ nominal pore size was submerged in the activated sludge solution of MLSS 5,000 mg/L. The critical permeate flux was measured as $26.6L/m^2{\cdot}hr$ by the method of continuous flux step change. TMPs of the filtration/relaxation (FR), FR with backwashing (FR/BW) and SFCO modes were measured. The SFCO mode was more effective than FR and FR/BW modes below the critical permeate flux such as 15, 20 and $25L/m^2{\cdot}hr$. However, the FR/BW was confirmed as more effectively fouling controlled mode than SFCO mode above the critical permeate flux.

Sampling and Extraction Method for Environmental DNA (eDNA) in Freshwater Ecosystems (수생태계의 환경유전자(environmental DNA: eDNA) 채집 및 추출기술)

  • Kim, Keonhee;Ryu, Jeha;Hwang, Soon-jin
    • Korean Journal of Ecology and Environment
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    • v.54 no.3
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    • pp.170-189
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    • 2021
  • Environmental DNA (eDNA) is a genetic material derived from organisms in various environments (water, soil, and air). eDNA has many advantages, such as high sensitivity, short investigation time, investigation safety, and accurate species identification. For this reason, it is used in various fields, such as biological monitoring and searching for harmful and endangered organisms. To collect eDNA from a freshwater ecosystem, it is necessary to consider the target organism and gene and a wide variety of items, such as on-site filtration and eDNA preservation methods. In particular, the method of collecting eDNA from the environment is directly related to the eDNA concentration, and when collecting eDNA using an appropriate collection method, accurate (good quality) analysis results can be obtained. In addition, in preserving and extracting eDNA collected from the freshwater ecosystem, when an accurate method is used, the concentration of eDNA distributed in the field can be accurately analyzed. Therefore, for researchers at the initial stage of eDNA research, the eDNA technology poses a difficult barrier to overcome. Thus, basic knowledge of eDNA surveys is necessary. In this study, we introduced sampling of eDNA and transport of sampled eDNA in aquatic ecosystems and extraction methods for eDNA in the laboratory. In addition, we introduced simpler and more efficient eDNA collection tools. On this basis, we hope that the eDNA technique could be more widely used to study aquatic ecosystems and help researchers who are starting to use the eDNA technique.