• 대한환경공학회지
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• 제34권1호
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• pp.42-48
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• 2012

본 연구에서는 미세기포 액막화 부상조를 이용하여 인 제거에 관한 연구를 실시하였다. 미세기포 액막화 부상조는 기체용해탱크를 이용하여 부상 전 기 액을 충분히 용해시킨 후 일정한 저 압력으로 동일한 미세기포를 생성하도록 하는 방법을 사용하였다. $A_2O$ 공정과 m-$O_3$(미세기포 생성장치와 오존용해탱크가 결합된 공정)복합공정을 거친 2차 유출수를 인 제거 공정의 유입수로 사용하였으며, 원수의 T-P 농도가 2.89 mg/L일 때, 8%의 Alum을 30 mg/L의 농도로 주입하였을 경우 T-P 제거율이 94%를 나타내었고, T-P의 방류수수질기준인 0.2 mg/L 이하를 만족시키는 것으로 조사되었으며, 계절에 따른 수온 변화는 T-P 제거 특성에 영향을 주지 않았다. SS의 유입농도가 1.0 mg/L 이상일 시 SS가 응집공정 내의 seed 역할을 하여 평균 T-P의 제거율이 97% 이상 되는 것으로 조사되었고, 부상스컴을 50% 반송할 경우, 부상스컴 내에 포함되어 있는 응집제 성분 Al이 주입되는 응집제의 역할을 보조하여 오염물질의 응집효율을 극대화 시키는 것으로 조사되었다. 이러한 조건에서 T-P의 방류수 수질기준 0.2 mg/L 이하를 만족하는 0.18 mg/L의 농도를 나타내는 것으로 조사되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권1호
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• pp.102-108
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• 2006

Microbial transglutaminase (MTGase) was investigated to determine whether it was an effective binding agent for the processing of low-quality pork loins. MTGase especially promoted the coagulation of myosin heavy chain (MHC). However, the effect of MTGase on MHC from low-quality meat was less than that from the normal meat when the reaction time was not enough. The breaking strength of the heat-induced gel made of myosin B from low-quality meat with MTGase was lower than that of normal meat. Sausage made with low-quality meat with MTGase did not exhibit improved hardness, as compared to that made with normal meat. Results of this study indicated that use of low-quality meat in the manufacture of sausage was feasible to get textural property equal to that of normal meat sausage, when a half or more of the raw material was normal meat and MTGase was used in the sausage.

• 상하수도학회지
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• 제24권1호
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• pp.103-108
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• 2010

Until now, research reports that it is difficult for brokenup floc after coagulation to reaggregate and settling efficiency of reaggregated floc is relatively low have dominated in water treatment process. In contrast, from recent study conducted by the French researcher, because the density of the reaggregated floc was higher than the previous floc, the settling efficiency of reaggregated floc increased. In this study, 15 times wet test were carried out and the removal efficiency of reagrregated floc was considerably increased. Moreover, this result was explained using the turbulent model for the flow occurred around the floc. Consequently, in the case of suitable hydrodynamic condition for the reaggregation, the characteristics of the reaggregated floc was changed into the favorable condition for improvement of settling efficiency. Also, the most important factor for reaggregation of floc was governed by hydrodynamic shear stress.

• 한국물환경학회지
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• 제24권6호
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• pp.682-689
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• 2008

The purpose of this study was to find out the variation between molecular size distribution (MSD) of natural organic matter (NOM) in raw waters after different water treatment processes like conventional process (coagulation, flocculation, filtration) followed by advanced oxidation process (ozonation, GAC adsorption). The MSD of NOM of Suji pilot plant were determined by Liquid Chromatography-Organic Carbon Detection (LC-OCD) which is a kine of high-performance size-exclusion chromatography (HPSEC) with nondispersive infrared (NDIR) detector and $UV_{254}$ detector. Five distinct fractions were generally separated from water samples with the Toyopearl HW-50S column, using 28 mmol phosphate buffer at pH 6.58 as an eluent. Large and intermediate humic fractions were the most dominant fractions in surface water. High molecular weight (HMW) matter was clearly easier to remove in coagulation and clarification than low molecular weight (LMW) matter. Water treatment processes removed the two largest fractions almost completely shifting the MSD towards smaller molecular size in DW. No more distinct variation of MSD was observed by ozone process after sand filtration but the SUVA value were obviously reduced during increase of the ozone doses. UVD results and HS-Diagram demonstrate that ozone induce not the variation of molecular size of humic substance but change the bond structure from aromatic rings or double bonds to single bond. Granular activated carbon (GAC) filtration removed 8~9% of organic compounds and showed better adsorption property for small MSD than large one.

• 한국광물학회지
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• 제20권4호
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• pp.339-349
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• 2007

다양한 광석 유형을 이루는 풍촌층 석회석에 대해서 제지 산업용 충전재로서의 적용가능성을 검토하기 위해 전기영동광산란 분광광도계와 주사전자현미경을 사용하여 석회석 미분체의 입도 및 형상을 비롯한 제반 광물 특성을 조사하였다. 또한 습식 제지 공정에서의 적용성과 효율성을 검증하기 위해 미분체의 현탁액 상에서 제타전위를 측정하고 응집 특성을 평가하였다. 풍촌층 석회석의 미분체는 원광의 광물 특성에 규제되어 광석 유형별로 서로 다른 형상 성향을 보이고 이에 따라 미세입도 분포, 제타전위 그리고 응집 특성도 다르게 나타난다. 또한 실험적으로 제작된 초지 상에서 측정된 백색도, 명도, 불투명도 및 인장강도도 석회석의 광석 유형에 따라 역시 현격한 차이를 보인다. 이는 기본적으로는 석회석 미분체의 백색도, 입도, 굴절률과 같은 광학적 성질과 분체의 형상 특성이 복합적으로 작용한 결과에 기인한 것으로 여겨진다. 이 연구 결과에 의하면, 제지 용도로의 활용 면에서 풍촌층 석회석의 모든 광석 유형들은 충분히 적용될 수 있을 것으로 여겨진다. 특히 명도와 백색도면에서 높은 수치를 나타내는 거정질 방해석형 광석이 전반적으로 제지 용도로 유리한 입장에 있는 것으로 판단된다. 또한 미정질 방해석형 광석은 불규칙한 입자의 형상으로 인해 특히 인장강도 면에서 좋은 품질 조건을 갖춘 것으로 평가된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.251-251
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• 2016

For several decades, industrial processes consume a huge amount of raw water for various objects that consequently results in the generation of large amounts of wastewater. Wastewaters are consisting of complex mixture of different inorganic and organic compounds and some of them can be toxic, hazardous and hard to degrade. These effluents are mainly treated by conventional technologies such are aerobic and anaerobic treatment and chemical coagulation. But, these processes are not suitable for eliminating all hazardous chemical compounds form wastewater and generate a large amount of toxic sludge. Therefore, other processes have been studied and applied together with these techniques to enhance purification results. These include photocatalysis, absorption, advanced oxidation processes, and ozonation, but also have their own drawbacks. In recent years, electrochemical techniques have received attention as wastewater treatment process that could be show higher purification results. Among them, boron doped diamond (BDD) attract attention as electrochemical electrode due to good chemical and electrochemical stability, long lifetime and wide potential window that necessary properties for anode electrode. So, there are many researches about high quality BDD on Nb, Ta, W and Si substrates, but, their application in effluents treatment is not suitable due to high cost of metal and low conductivity of Si. To solve these problems, Ti has been candidate as substrate in consideration of cost and property. But there are adhesion issues that must be overcome to apply Ti as BDD substrate. Al, Cu, Ti and Nb thin films were deposited on Ti substrate to improve adhesion between substrate and BDD thin film. In this paper, BDD films were deposited by hot filament chemical vapor deposition (HF-CVD) method. Prior to deposition, cleaning processes were conducted in acetone, ethanol, and isopropyl alcohol (IPA) using sonification machine for 7 min, respectively. And metal layer with the thickness of 200 nm were deposited by DC magnetron sputtering (DCMS). To analyze microstructure X-ray diffraction (XRD, Bruker gads) and field emission scanning electron microscopy (FE-SEM, Hitachi) were used. It is confirmed that metal layer was effective to adhesion property and improved electrode property. Electrochemical measurements were carried out in a three electrode electrochemical cell containing a 0.5 % H2SO4 in deionized water. As a result, it is confirmed that metal inter layer heavily effect on BDD property by improving adhesion property due to suppressing formation of titanium carbide.

• 접착 및 계면
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• 제7권4호
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• pp.32-38
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• 2006

A series of organic-inorganic hybrids, PCL/EP/$SiO_2$, involving epoxy resin and triethoxysilane-terminated polycaprolactone elastomer (PCL-TESi) were prepared via polymerization of diglycidyl ether of bisphenol A (DGEBA) with amine curing agent KB-2 and sol-gel process of PCL-TESi. The curing reactions were started from the initially homogeneous mixture of DGEBA, KB-2 and the PCL-TESi. The organicinorganic hybrids containing up to 4.95% (wt) of $SiO_2$ were obtained and characterized by FT-IR, transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). It was experimentally shown that the swelling property in toluene, morphologies and thermal properties of the resulting hybrids were quite dependent on the contents of $SiO_2$. The crosslink network density decreases with increasing of the PCL-TESi. And in TEM, the phase separated morphology of these hybrids was found, which resulted from the coagulation of Si-O-Si networks resulting from $-Si(OC_2H_5)_3$ of PCL-TESi self-curing by hydrolytic silanol condensation, with the advancement of the curing reaction in the modified epoxy resin systems. Meanwhile, the change of the $SiO_2$ content made the morphologies changed from aggregated particles of Si-O-Si in the hybrid to nanocluster of interconnected Si-O-Si particles, then to aggregated Si-O-Si dispersing in the continuous cured epoxy phase again, and last to co-continuous interpenetrating network. The glass transition behavior of the hybrid material was cooperative motion of large chain segments, which were hindered by the inorganic Si-O-Si network. And in TG analysis, the characteristic temperature at 5% of weight loss was evidently increased from $120.5^{\circ}C$ of pure cured epoxy to $277.6^{\circ}C$ of 3.84% (wt) of $SiO_2$ modified epoxy due to the existence of Si-O-Si when PCL-TESi was added in the hybrid.

• BMB Reports
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• 제30권1호
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• pp.37-40
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• 1997

Earthworm extracts are known for anti-inflammatory, analgesic. antipyretic, and anticancer effects but can also influence blood circulation. It was previously shown that an earthworm, Lumbricus rubelius. contained a water-extractable anticoagulant which was a heat- and acid-stable molecule with hydrophilic property. In order to uncover the biochemical nature of this molecule, the anticoagulant was processed with various hydrolases such as trypsin, DNase, RNase. and lysozome. When the digested samples were analyzed with an in vitro coagulation test measuring activated partial thromboplastin time (APTT) and agarose gel electrophoresis, the anticoagulant proved to be a relatively homogeneous DNA fragment with relative molecular size around 72 base pairs. Interestingly, the activity was further stimulated with a trypsin digestion. RNA. on the other hand, did not prolong the APTT. It was also demonstrated that the DNA accelerated the antithrombin III (AT-III) inhibition of thrombin from $IC_{50}$ of 0.34 to 0.16 unit determined with S-2238 as a substrate, whereas heparin, a popular anticoagulant. shifted the value to 0.05. Therefore, it is suggested that the DNA could be considered as an alternative antithrombotic agent to heparin, which would exhibits bleeding side effects.

• Carbon letters
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• 제13권4호
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• pp.191-204
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• 2012

Carbon nanotubes (CNTs) have exceptional mechanical, electrical, and thermal properties compared with those of commercialized high-performance fibers. For use in the form of fabrics that can maintain such properties, individual CNTs should be held together in fibers or made into yarns twisted out of the fibers. Typical methods that are used for such purposes include (a) surfactant-based coagulation spinning, which injects a polymeric binder between CNTs to form fibers; (b) liquid-crystalline spinning, which uses the nature of CNTs to form liquid crystals under certain conditions; (c) direct spinning, which can produce CNT fibers or yarns at the same time as synthesis by introducing a carbon source into a vertical furnace; and (d) forest spinning, which draws and twists CNTs grown vertically on a substrate. However, it is difficult for those CNT fibers to express the excellent properties of individual CNTs as they are. As solutions to this problem, post-treatment processes are under development for improving the production process of CNT fibers or enhancing their properties. This paper discusses the recent methods of fabricating CNT fibers and examines some post-treatment processes for property enhancement and their applications.

• Elastomers and Composites
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• 제35권3호
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• pp.196-204
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• 2000

방수제로 사용하는 EVA 에멀젼 수지에 라텍스 형태의 아크릴 수지, 에폭시 수지, 우레탄 수지, SBR 수지를 전체 혼합물 중에 $0{\sim}50%$ 혼합하여 소포성, 기계적 물성, 내수성 등을 조사하였다. 소포제의 소포효과는 BYK-021이 가장 우수하였으며 적절한 사용량은 전체 혼합물에 대하여 0.3phr이었다. 수축율은 수지간의 상용성과 기공형성도에 영향을 받았으며 기계적 강도는 수지 분자간의 응집력, 수지와 시멘트의 결합력, 시멘트 입자간의 응집력 등에 영향을 받았다. 라텍스를 혼합한 것은 혼합하지 않은 것보다 수축율, 굴곡강도, 접착강도, 충격강도 등에서 우수한 물성을 나타내었다. EVA에 시멘트를 혼합했을 때에는 혼합하지 않았을 때보다 내수성이 떨어졌다.