• KSBB Journal
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• 제22권4호
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• pp.244-248
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• 2007

고농도 페놀폐수 전처리 습식산화공정의 반응온도, 초기 pH 및 균일촉매 ($CuSO_4$) 등이 후처리 호기성 생물학적 공정에 미치는 영향을 조사하였다. 습식산화에서의 높은 반응온도와 산성 초기조건이 후처리 생물학적 산화공정에서 높은 산화속도와 최종 COD 제거율을 유발하였다. 습식산화에서 균일촉매를 사용하면 전처리 습식산화반응은 낮은 반응온도에서도 높은 COD 제거속도를 보였으나, 후처리 생물학적 산화공정에서는 낮은 최종 COD 제거율을 나타내었다.

• 한국세라믹학회지
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• 제54권2호
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• pp.108-113
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• 2017

The use of aluminum-based coagulants in water pretreatment is being carefully considered because aluminum exposure is a risk factor for the onset of Alzheimer's disease. Lightly burned-dolomite kiln dust (LB-DKD) was evaluated as an alternative coagulant because it contains high levels of the healthful minerals calcium and magnesium. An organic pore forming agent (OPFA) was incorporated to prepare porous granules after OPFA removal through a thermal decomposition process. A spray drying method was used to produce uniform and reproducible spherical granules with low density, since fine dolomite particles have irregular agglomeration behavior in the hydration reaction. The use of fine dolomite powder and different porosity granules led to a visible color change in raw algae (RA) containing water, from dark green to transparent colorlessness. Also, dolomite powders and granules exhibited a mean removal efficiency of 48.3% in total nitrogen (T-N), a gradual increase in the removal efficiency of total phosphorus (T-P) as granule porosity increased. We demonstrate that porous dolomite granules can improve the settling time and water quality in summer seasons for the emergent treatment of excessive algal blooms in eutrophic water.

• 한국식품과학회지
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• 제29권5호
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• pp.1021-1027
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• 1997

Dicyma sp. YCH-37이 생산하는 효모세포벽 용해효소의 성질을 검토한 결과, 각종 환원제와 금속이온에 대체로 안정하였고, guanidine-HCl을 제외한 여러 화학수식제에 대해서도 안정하였다. 배양시간, 전처리 및 배양조건에 따른 영향을 검토한 결과, 정지기 및 사멸기에 있는 효모보다는 대수증식기의 효모, 그리고 생효모에 비해 열처리된 효모가 더 잘 용균되었다. Butanol, acetone 등의 유기용매로 처리된 효모가 그렇지 않은 효모보다 용균도가 좋았으며, 0.5 M ammonium sulfate가 함유된 Yeast extract-Malt extract 배지에서 생육한 효모, 그리고 진탕배양한 효모보다 정치배양한 효모가 용균효소에 의해 더 잘 용균되었다. SDS, Triton X-100, ${\beta}-mercaptoethanol$, potassium chloride, sodium sulfite 등의 화학수식제를 효소반응액에 첨가하였을 때 기질 효모는 더 잘 용균되었다.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.921-929
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• 2011

Stimulation of AMP-activated protein kinase (AMPK) signaling followed by increase of glucose uptake in L6 myotubes were studied with organic solvent extract of Malva verticillata (MV) seeds. Ethanol extract of M. verticillata seeds (MVE) significantly increased the phosphorylation level of AMPK, acetyl-CoA carboxylase (ACC), and glucose uptake in L6 myotube cells. The MVE was fractionated with n-hexane (MVE-H), chloroform (MVE-C), ethylacetate (MVE-E), n-butanol (MVE-B), and water (MVE-W). MVE-H (150 ${\mu}g$/ml) showed the highest phosphorylating activity and increased glucose uptake by 2.3-fold. Oral administration of MVE-H (40 mg/kg) for 4 weeks to type 2 diabetic (db/db) mice reduced non-fasting and fasting blood glucose levels by 17.1% and 23.3%, respectively. Phosphorylation levels of AMPK and ACC in the soleus muscle and liver tissue of db/db mice were significantly increased by the administration of MVE-H. MVE-H was further fractionated using preparative HPLC to identify the AMPK-activating compounds. The NMR and GC-MS analyses revealed that ${\beta}$-sitosterol was a major effective compound in MVE-H. Phosphorylation levels of AMPK and ACC, and glucose uptake were significantly increased by the treatment of MVE-S (${\beta}$-sitosterol) isolated from M. verticillata to L6 cells, and these effects were attenuated by an AMPK inhibitor (Compound C) pretreatment. These results, taken together, demonstrate that increased glucose uptake in L6 myotubes by MVE-H treatment is mainly accomplished through the activation of AMPK. Our finding suggests that the extract isolated from M. verticillata seed would be beneficial for the treatment of metabolic disease including type 2 diabetes and hyperlipidemia.

• 대한환경공학회지
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• 제31권10호
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• pp.865-872
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• 2009

슬러지의 감량과 최종처분 기술 개발을 위해 실험실 규모 호기성 소화공정을 279일간 운전하였다. 혐기성 소화 슬러지를 원료로 $40^{\circ}C$에서 120분간 알칼리 전처리하여 호기성 소화조에 유입시켰다. 유입 슬러지 성상과 HRT의 변화에 따라 소화효율의 변화가 있었으며 적정 HRT는 6일인 것으로 나타났다. 이때 $NH_3$-N, SCOD, TKN, TCOD, SS, VSS의 평균 제거율(소화조 유입 슬러지 기준)은 각각 97.4%, 81.7%, 68.7%, 61.4%, 50.6%, 47.0% 이었다. SS는 전처리와 호기성 소화를 통해 원료 슬러지(23,920 mg/L)의 73.9% 감량화가 가능하였다. 처리 슬러지는 약 350 mg/L의 SCOD를 포함하고 있어 액비로 활용하기에 무리가 없을 것으로 판단되었다. HRT를 5일 이상으로 유지할 경우 질산화 반응이 활성화되었으며 최대 658 mg/L의 유출 슬러지 질산성 질소 농도를 얻을 수 있었다. 암모니아성 질소 농도는 20 mg/L 내외로 크게 감소하였다.

• Journal of Acupuncture Research
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• 제18권2호
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• pp.111-122
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• 2001

Objectives ; This study was undertaken to determine if Salviae Radix herb-acupuncture (SRA) exerts protective effect against alterations in membrane transport function in rabbits with mercury chloride (Hg)-induced acute renal failure. Methods and Results ; The administration of Hg at a subcutaneous single dose of 10mg/kg caused a reduction in GFR to 9.4% of the basal value and an increase in fractional Na+ excretion to 10-fold, indicating generation of acute renal failure. When animals were acupunctured with $0.5m{\ell}$ of SRA extract (0.1%) in both sides of Shinsu(BL23) for 7 days prod to Hg administration, such changes were significantly attenuated. The fractional excretion of glucose and phosphate was increased to approximately 132-fold and 7-fold, respectively, in rabbits treated with Hg alone, but the fractional excretion of glucose was increased to 26-fold and that of phosphate was not different from the basal value in SRA-pretreated rabbits. Uptakes of glucose and phosphate in purified isolated brush-border membrane and $Na^+-K^+$-ATPase activity in microsomal fraction were inhibited in rabbits treated with Hg alone, suggesting that impairment in proximal reabsorption of glucose and phosphate is resulted from a direct damage of membrane transport carriers and disruption of the normal $Na^+$ gradient. Conclusions ; Such changes were prevented by SRA. Uptakes of organic ions, PAH and TEA, in renal cortical slices were inhibited by the administration of Hg, which was prevented by SRA. Pretreatment of an antioxidant DPPD attenuated the increase in the fractional excretion of glucose and phosphate induced by the administration of Hg.

• 대한화학회지
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• 제21권6호
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• pp.427-433
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• 1977

강물 시료속에 함유된 크롬, 철, 란탄, 스칸듐 및 아연의 함량을 방사화 분석법으로 동시정량하는 방법을 확립하였다. 10ml의 강물 시료를 사전 처리없이 석영관 속에 밀봉한 다음 열중성자속이 $1{\times}10^{13}n{\cdot}cm^{-2}{\cdot}sec^{-1}$인 곳에서 1주일간 조사하였다. 약 2일간 냉각시킨 후 시료 속에든 원소들을 0.1M 옥신의 클로로포름용액으로 여러 pH에서 연속적으로 추출하였다. 감마선 분광분석을 위하여 유기층을 800챈널 펄스높이 분석기에 연결된 $″3\;{\times}\;3″$ NaI (T1) 검출기로 계측하였다. 본분석법에 의하여 대부분의 강물 시료에 ppb 농도범위로 함유된 이들 원소들의 정량이 가능하였다. 추적자를 써서 이들 원소의 정량적 분리를 위한 연구를 수행하였다.

• 한국재료학회지
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• 제27권12호
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• pp.699-704
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• 2017

Recently, the use of an aluminum nitride(AlN) buffer layer has been actively studied for fabricating a high quality gallium nitride(GaN) template for high efficiency Light Emitting Diode(LED) production. We confirmed that AlN deposition after $N_2$ plasma treatment of the substrate has a positive influence on GaN epitaxial growth. In this study, $N_2$ plasma treatment was performed on a commercial patterned sapphire substrate by RF magnetron sputtering equipment. GaN was grown by metal organic chemical vapor deposition(MOCVD). The surface treated with $N_2$ plasma was analyzed by x-ray photoelectron spectroscopy(XPS) to determine the binding energy. The XPS results indicated the surface was changed from $Al_2O_3$ to AlN and AlON, and we confirmed that the thickness of the pretreated layer was about 1 nm using high resolution transmission electron microscopy(HR-TEM). The AlN buffer layer deposited on the grown pretreated layer had lower crystallinity than the as-treated PSS. Therefore, the surface $N_2$ plasma treatment on PSS resulted in a reduction in the crystallinity of the AlN buffer layer, which can improve the epitaxial growth quality of the GaN template.

• 폴리머
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• 제33권1호
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• pp.33-38
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• 2009

은 카바메이트 착체 화합물의 환원에 의한 무전해 도금법으로 은/폴리스티렌 비드를 제조하기 위하여 폴리스티렌 및 아민 관능기를 가지는 공중합체 비드를 제조하였다. 스티렌, divinylbenzene(DVB) 그리고 2-(N,N-dimethylamino)ethyl methacrylate (DAEMA) 단량체들을 poly(vinyl alcohol) 존재 하에서 물/메탄올을 용매로 사용하여 무유화중합을 진행하였다. 30/0$\sim$1.5/0$\sim$3 wt%의 단량체 조성을 가지는 poly(styrene/DVB/DAEMA) 비드는 구형으로 1 ${\mu}m$의 일정한 크기를 가지고 있었다. 아민 기능기를 가지는 폴리스티렌 비드의 무전해 도금은 비드의 전처리 없이 silver 2-ethylhexylcarbamate (Ag-EHCB) 복합체와 히드라진 환원제를 사용하여 메탄올 용액에서 진행하였다. 제조된 비드와 도금된 비드 표면의 형태를 SEM으로 관찰하였으며 은 도금된 비드를 분산시켜 자외선 흡수 변화 그리고 도금된 은의 성분을 XRD로 분석하였다.

• 상하수도학회지
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• 제19권3호
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• pp.338-347
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• 2005

Horizontal-Flow Roughing Filtration (HRF) is one of altemative pretreatment methods e.g. prior to Slow Sand Filtration (SSF). However, some of its limitations are that the effluent quality drops drastically at higher turbidity (>200 NTU) and at higher filtration rate (>1 m/h). To overcome these drawbacks, we suggested Direct Horizontal-Flow Roughing Filtration (DHRF), which is a modified system of Horizontal-Flow Roughing (HRF) by addition of low dose of coagulant prior to filtration. In this study to optimize the DHRF configuration, a conceptual and mathematical model for the coarse compartment has been developed in analogy with multi-plate settlers. Data from simple column settling test can be used in the model to predict the filter performance. Furthermore, the model developed herein has been validated by successive experiments carried out. The conventional column settling test has been found to be an handy and useful to predict the performance of DHRF for different raw water characteristics (e.g. coagulated or uncoagulated water, different presence of organic matter, etc.) and different inital process conditions (e.g. coagulant dose, mixing time and intensity, etc.). An optimum filter design for the coarse compartment (grain size 20mm) has been found to be of 3 m/h filtration rate with filter length of 4-4.5 m.