• Title/Summary/Keyword: 선택과 제거

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Technical Feasibility for Hollow-Fiber Ultrafiltration Water Treatment System and its Economic Aspects (중공사형 한외여과막 수처리 공정의 기능성과 막을 사용한 수처리공정의 경제성에 관한 연구)

  • Wang, Jin-Soo;Kim, Byung-Jick;Choi, Soo Hyoung
    • Applied Chemistry for Engineering
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    • v.10 no.1
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    • pp.12-18
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    • 1999
  • This research was undertaken to do the technical and economical feasibility study of membrane water treatment system. For the technical feasibility study, batch water treatment system using UF(ultrafiltration) was set up and several experiments were carried out. The performance of the UF membrane was tested in terms of turbidity. The experimental results showed that the UF membrane process produced less than 1 NTU water regardless of input water turbidity. For the economical feasibility study, the cost model was analyzed and programmed for simulation. Also costs of the membrane water treatment and the conventional treatment were evaluated. The simulation results showed that the unit production cost increased when design flow or permeate flow decreased. The production cost of membrane water treatment system was lower than that of the conventional system. Both technical and economical feasibility study showed that the UF membrane water purification system was a very competitive water purification process.

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Design of Pretreatment Process of Lead Frame Etching Wastes Using Reduction-Oxidation Method (환원-산화법을 이용한 리드프레임 에칭폐액의 정제과정 설계)

  • Lee, Seung Bum;Jeon, Gil Song;Jung, Rae Yoon;Hong, In Kwon
    • Applied Chemistry for Engineering
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    • v.27 no.1
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    • pp.21-25
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    • 2016
  • When copper alloy is used in etching process for the production of lead frame, the high concentration of heavy metals, such as iron, nickel and zinc may be included in the etching waste. Those etching waste is classified as a specified one. Therefore a customized design was designed for the purification process of the lead frame etching waste liquid containing high concentrations of heavy metals for the production of an electroplating copper(II) oxide. Since the lead frame etching waste solution contains highly concentrated heavy metal species, an ion exchange method is difficult to remove all heavy metals. In this study, a copper(I) chloride was manufactured by using water solubility difference related to the reduction-oxidation method followed by the reunion of copper(II) chloride using sodium sulfate as an oxidant. The hydrazine was chosen as a reducing agent. The optimum added amount was 1.4 mol per 1.0 mol of copper. In the case of removal of heavy metals by using the combination of reduction-oxidation and ion exchange resin methods, 4.3 ppm of $Fe^{3+}$, 2.4 ppm of $Ni^{2+}$ and 0.78 ppm of $Zn^{2+}$ can be reused as raw materials for electroplating copper(II) oxide when repeated three times.

The Effect of Biomass Torrefaction on the Catalytic Pyrolysis of Korean Cork Oak (굴참나무 촉매열분해에 바이오매스 반탄화가 미치는 영향)

  • Lee, Ji Young;Lee, Hyung Won;Kim, Young-Min;Park, Young-Kwon
    • Applied Chemistry for Engineering
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    • v.29 no.3
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    • pp.350-355
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    • 2018
  • In this study, the effect of biomass torrefaction on the thermal and catalytic pyrolysis of cork oak was investigated. The thermal and catalytic pyrolysis behavior of cork oak (CO) and torrefied CO (TCO) were evaluated by comparing their thermogravimetric (TG) analysis results and product distributions of bio-oils obtained from the fast pyrolysis using a fixed bed reactor. TG and differential TG (DTG) curves of CO and TCO revealed that the elimination amount of hemicellulose in CO increased by applying the higher torrefaction temperature and longer torrefaction time. CO torrefaction also decreased the oil yield but increased that of solid char during the pyrolysis because the contents of cellulose and lignin in CO increased due to the elimination of hemicellulose during torrefaction. Selectivities of the levoglucosan and phenolics in TCO pyrolysis oil were higher than those in CO pyrolysis oil. The content of aromatic hydrocarbons in bio-oil increased by applying the catalytic pyrolysis of CO and TCO over HZSM-5 ($SiO_2/Al_2O_3=30$). Compared to CO, TCO showed the higher efficiency on the formation of aromatic hydrocarbons via the catalytic pyrolysis over HZSM-5 and the efficiency was maximized by applying the higher torrefaction and catalytic pyrolysis reaction temperatures of 280 and $600^{\circ}C$, respectively.

The Growth Inhibiting Effect of Vibrio parahaemolyticus KCTC 2471 by the Natural Products Bearing Antioxidative Capacity (Vibrio Parahaemolyticus KCTC 2471에 대한 항산화 천연산물의 성장 억제 효과)

  • 김종덕
    • Journal of Life Science
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    • v.12 no.6
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    • pp.731-739
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    • 2002
  • The growth of V. parahaemolyticus was inhibited by the combination of natural products having antioxidative capacity. The growth of V. parahaemolyticus was controlled effectively by each or the combination of Paeonia japonica, Acanthodanacis cortex, Phellodendri cortex, Mori cortex radicis, Theae folium, Galla rhois, Coptidis rhizomn and Astragali radix. The growth inhibition ratio of the combination of Astragali radix, Phellodendri cortex, Coptidis rhizotna and Paeonia japonica was 95%, and its antioxidative capacity was also 5.4 times higher, and the elimination ratio of hydroxyl radical was more than 80% compared with control. As natural products might activate some parts of human body, they could be utilized as pharmaceuitcal applications, functional foods, antiaging tea, and multifunctional fermentative beverages.

항 바이러스성 Carbocyclic nucleoside류의 합성

  • 김희두;최명희
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.229-229
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    • 1994
  • 선택성이 높고 뛰어난 약효를 지닌 항 바이러스제의 개발은 신약개발의 중요한 영역중에 하나이다. 현재 AIDS 치료제로 사용되고 AZT를 비롯하여 항virus 효과를 나타내는 약물의 대부분은 구조적으로 nucleoside계에 속하는 화합물로서 수 많은 약리학적 연구 및 합성 화학적 연구가 이루어져 왔다. 특히 합성 화학적 측면에서 이들 화합물의 합성은 크게 두가지로 나누어지는데 그것은 sugar 부위의 변형을 통한 방법과 염기 부위의 변형을 통한 방법에 의해 새로운 항 바이러스제를 개발하는 것이다. 최근의 연구 동향에 있어서 주목할 만한 변화의 하나는 sugar 부위의 구조적 변형을 시도하는데 있어서 종래의 5원환 형태에서 환이 개열된 형태의 acyclic nucleoside에 대한 연구가 이루어져 좋은 효과를 거두고 인다는 사실이다. Acyclovir, Ganciclovir등 의 개발이 그것이다. 본 연구에서는 종래의 acyclic nucleoside가 ribose sugar의 2'번 및 3'번 탄소를 제거한 acyclic ether 형태로 되어있는 것과는 다르게 ether 부위의 산소를 탄소 치환한 carbo-acyclic nucleoside를 합성하고자 하였다. Acyclic nucleoside를 합성하고자 하였다. Acyclic nucleoside의 side chain의 conformation이 항 바이러스 작용을 나타내는데 필수 불가결한 점을 감안할때, carbo-acyclic nucleoside계 화합물은 보다 다양하게 변형될 수 있는 장점을 가지고 있다. 이러한 관점에서 side chain의 2'번 및 3'번 탄소는 side chain의 conformation을 좌우하는 결정적 요인으로 작용할 것으로 판단된다. 따라서 본 연구에서는 이들 탄소를 중심으로한 분자수식을 시도하기로 하고 bioisosterism을 이용하여 3'위치의 수소를 fluoride로 치환한 화합물을 설계하여 합성을 시도하였다.silyl group-5'-무치환 화합물을 tosyl, azido화 한다음 desilylation하여 얻었다. 목적하는(1) 화합물의 diasteromer 인 2',3'-dihydroxy-5'-무치환 유도체(3)는 (4)화합물 합성시 얻은 hemiactal을 key intermediate로 하여 TsNHNH$_2$, NaB(CN)H$_3$ 및 NaOAc로 처리하므로서 얻을수 있었다. 이들 화합물들의 각종 DNA 및 RNA virus에 대한 항 바이러스작용을 검토한 결과 현저한 항 바이러스 작용을 나타내지 않았다.분화유도 활성을 나타내어 항종양제로의 개발에 많은 흥미가 기대된다.기대된다.oxylic acid (compound 10)를 합성하였다.10^{-7}$ M)에 의한 단백인산화에 대하여는 더 미약한 억제-효과를 나타내었다. 이상의 결과는 PDE-1과 항우울약들의 항혈소판작용은 PKC-기질인 41-43 kD와 20 kD의 인산화를 억제함에 기인되는 것으로 사료된다.다. 것으로 사료된다.다.바와 같이 MCl에서 작은 Dv 값을 갖는데, 이것은 CdCl$_{4}$$^{2-}$ 착이온을 형성하거나 ZnCl$_{4}$$^{2-}$ , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서던지 NH$_{4}$$^{+}$의 경우 Dv값이 제일 작았다. 바. 본 연구의 목적중의 하나인 인체유해 중금속이온인 Hg(II), Cd(II)등이 NaCl같은 염화물이 함유된 시료용액에 공해이온으로 존재할 경우 흡착에 의한 제거가 가능하다. 한편 이같은 중금속이온의 흡착실험은 특히 해수중의 금속이온의 회수연구에도

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Study on an Image Reconstruction Algorithm for 3D Cartilage OCT Images (A Preliminary Study) (3차원 연골 광간섭 단층촬영 이미지들에 대한 영상 재구성 알고리듬 연구)

  • Ho, Dong-Su;Kim, Ee-Hwa;Kim, Yong-Min;Kim, Beop-Min
    • Progress in Medical Physics
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    • v.20 no.2
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    • pp.62-71
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    • 2009
  • Recently, optical coherence tomography (OCT) has demonstrated considerable promise for the noninvasive assessment of biological tissues. However, OCT images difficult to analyze due to speckle noise. In this paper, we tested various image processing techniques for speckle removal of human and rabbit cartilage OCT images. Also, we distinguished the images which get with methods of image segmentation for OCT images, and found the most suitable method for segmenting an image. And, we selected image segmentation suitable for OCT before image reconstruction. OCT was a weak point to system design and image processing. It was a limit owing to measure small a distance and depth size. So, good edge matching algorithms are important for image reconstruction. This paper presents such an algorithm, the chamfer matching algorithm. It is made of background for 3D image reconstruction. The purpose of this paper is to describe good image processing techniques for speckle removal, image segmentation, and the 3D reconstruction of cartilage OCT images.

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Improvement of anti-oxidant and anti-inflammatory activities of aleurone layer extracts of black rice (Oryza sativa L.) by enzyme treatment (효소 처리에 의한 흑미 호분 추출물의 산화방지와 항염증 활성 증진)

  • Lee, Mi Kyoung;Ryu, Soo In;Lee, Min Ho
    • Korean Journal of Food Science and Technology
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    • v.50 no.5
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    • pp.528-534
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    • 2018
  • The current study investigated the effects of enzyme treatment on black rice (Oryza sativa L.) aleurone layer extracts. Different enzymes (lipase, lecitase ultra and lipopan 50BG) were used to test anti-oxidant and anti-inflammatory activities in vitro. The antioxidant activities of enzyme treated or non-enzyme treated extracts of black rice bran were evaluated via 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity. Lipase treated extracts of black rice bran showed higher antioxidant activity compared to that of non-enzyme treated extracts. Anti-inflammatory activities of enzyme treated black rice bran extracts on nitrite production and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) secretion, were tested using a nitric oxide (NO) colorimetric assay kit and an enzyme-linked immunosorbent assay (ELISA) kit. The ethanolic extract of enzyme treated black rice bran decreased the levels of nitric oxide production and pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$, in a lipopolysaccharidestimulated RAW 264.7 cell culture. These findings indicate that enhanced anti-oxidant and anti-inflammation activities of the ethanolic extracts of enzyme treated black rice (Oryza sativa L.) aleurone layers, may be attributed to molecular conversion of ingredients in enzyme catalyzed reactions.

Removal of Volatile Organic Compounds using Candida tropicalis Immobilized on Polymer Gel Media in an Airlift Loop Bioreactor (Candida tropicalis 포괄고정 담체를 적용한 Airlift Loop Bioreactor에서의 복합 휘발성유기화합물 제거)

  • NamGung, Hyeong-Kyu;Ha, Jeong-Hyub;Hwang, Sun-Jin;Song, Ji-Hyeon
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.8
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    • pp.603-610
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    • 2009
  • This research was performed to improve removal efficiency of toluene and methyl ethyl ketone (MEK) using Candida tropicalis, one of the yeast species. An airlift loop bioreactor (ALB) was employed to enhance the capability of mass transfer for toluene and MEK from the gas phase to the liquid, microbial phase. Polymer gel media made from PAC, alginate and PEG was applied for the effective immobilization of the yeast strain on the polymer gel media. The experimental results indicated that the mass transfer coefficient of toluene without polymer gel media was 1.29 $min^{-1}$ at a gas retention time of 15 sec, whereas the KLa value for toluene was increased to 4.07 $min^{-1}$ by adding the media, confirming the enhanced mass transfer of volatile organic compounds between the gas and liquid phases. The removal efficiency of toluene and MEK by using yeast-immobilized polymer gel media in the ALB was greater than 80% at different pollutant loading rates (5, 10, 19 and 37 g/$m^3$/hr for toluene, 4.5, 8.9, 17.8 and 35.1 g/$m^3$/hr for MEK). In addition, an elimination capacity test conducted by changing inlet loading rates stepwise demonstrated that maximum elimination capacities for toluene and MEK were 70.4 and 56.4 g/$m^3$/hr, respectively.

Decision Algorithm of Natural Algae Coagulant Dose to Control Algae from the Influent of Water Works (정수장 유입조류 전처리를 위한 천연조류제거제(W.H.)의 최적주입농도 결정)

  • Jang, Yeo-Ju;Jung, Jin-Hong;Lim, Hyun-Man;Yoon, Young H.;Ahn, Kwang-Ho;Chang, Hyang-Youn;Kim, Weon-Jae
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.9
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    • pp.482-496
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    • 2016
  • Algal blooms of cyanobacteria (blue-green Algae) due to the eutrophication of rivers and lakes can cause not only the damage by its biological toxins but also the economic loss in drinking water treatment. The natural algae coagulant, a commercial product known as W.H. containing the algicidal and allelopathic material derived from oak, can control algal problems proactively through the coagulation flotation process. However, because there have been no applications of the process for pre-treatment in drinking water plants, we could find no report on the optimum injection dose of W.H.. In this study, we have conducted several sets of jar-tests while changing W.H. dose and concentration of chl-a for (1) Han-river samples and (2) subcultured cyanobacteria samples, and monitored the removal mechanisms of algae intensively. Based on these jar-test results, two linear equations with variables of chl-a and turbidity have been deduced to predict the optimal W.H. dose after the multiple regression analysis using IBM-SPSS. Also, prototypes of automatic control logic have been suggested to inject the optimal W.H. dose promptly in response to the variation of water quality.

Influence of Intracerebroventricular Domperidone on Rabbit Renal Function (가토 신장기능에 미치는 뇌실내 Domperidone의 영향)

  • Kim, Young-Soo
    • The Korean Journal of Pharmacology
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    • v.24 no.1
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    • pp.135-145
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    • 1988
  • Dopamine when given icv induces antidiuresis along with transient natriuretic tendency, and it has been suggested that both subtypes of central dopamine receptors may influence renal function differentially. This study was undertaken to delineate the role of central $D_2$ receptors employing domperidone (DOM), a selective $D_2$ antagonist. DOM icv elicited antidiuresis and antinatriuresis in doses ranging from 15 to $135{\mu}g/kg$. GFR and RPF as well as sodium excretion decreased. Systemic blood pressure increased slightly. Intravenous DOM did not elicit significant changes in sodium excretion. Denervation of the kidney abolished the hemodynamic change induced by icv DOM, but sodium excretion decreased on both innervated and denervated kidneys. No diuretic tendency was uncovered by the denervation. Dopamine, $150{\mu}g/kg$ icv, produced antidiuresis along with decreases in hemodynamics. These effects were not affected by DOM-pretreatment, and no natriuretic tendency was unveiled. Bromocriptine, a $D_2$ receptor agonist, $200{\mu}g/kg$ icv, elicited marked diuresis and natriuresis, which were completely abolished by DOM-pretreatment. Apomorphine, another prototype of $D_2$ agonist, $150{\mu}g/kg$ icv, produced diuresis and natrituresis with increases in renal hemdoynamics, followed by decreases in all parameters. DOM-pretreatment did not affect the renal hemodynamic effects, wherease the increases in urine flow and sodium excretion were markedly reduced by DOM, Present study suggests that central $200{\mu}g/kg$ receptors mediate natriuretic and diuretic influence to the kidney, possibly through mediation of natriuretic humoral factor, and provide further evidence supporting the hypothesis that central $200{\mu}g/kg$ receptors mediate antidiuretic influence via nerve pathway, whereas natriuresis are brought about through mediation of central $200{\mu}g/kg$ receptors.

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