• Membrane and Water Treatment
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• 제7권6호
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• pp.507-520
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• 2016

The effect of ZnO on cellulose acetate in the removal of benzophenone-3 (BP-3) was investigated. The benzophenone-3 (BP-3) which is an endocrine disrupting chemical (EDC) was completely removed (100%) from the drinking water using Cellulose Acetate (CA) and zinc oxide (ZnO) composite membranes. The membranes were prepared by DIPS method and the filtration experiments were conducted by dead end filtration unit. The macrostructure of the membrane were studied by ATR-IR and XRD Spectra's. Atomic force microscopy (AFM) and Scanning electron microscopy (SEM) were used to study the micro properties of the membranes. The laboratory experiments such as water uptake study and pure water flux performed to confirm the increasing hydrophilicity. The enhancing hydrophilicity was confirmed with respect to higher the concentration of nanoparticles. Evaluation of BP-3 removal was carried in different experimental conditions, such as, different Trans membrane pressure and different concentration of feed. The membrane with low pressure showed better performance by rejecting 100% of BP-3. However, 1 ppm, 3 ppm and 6 ppm of feed solution was used and among them 3 ppm of feed solution gives 100% rejection. The ZnO nanoparticales enhances the performance of CA membrane by showing maximum rejection.

• 한국공간구조학회논문집
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• 제16권2호
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• pp.39-45
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• 2016

Membrane structure is a system that is stabilized by maintaining a tensile state of the membrane material that originally cannot resist the bending or pressure. Also, it is a system that allows the whole membrane structure to bear external loads caused by wind or precipitation such as snow, rain and etc. Tension relaxation phenomenon can transpire to the tension that is introduced to the fabric over time, due to the innate characteristics of the membrane material. Thus, it is important to accurately understand the size of the membrane tension after the completion of the structures, for maintenance and management purposes. The authors have proposed the principle of theoretically and indirectly measuring the tension by vibrating the membrane surface with sound waves exposures against the surface, which is compartmentalized by a rectangular boundary, and by measuring the natural frequency of the membrane surface that selectively resonates. The authors of this paper measured the tension of preexisting membrane structure for its maintenance by using the developed portable measurement equipment. Through analyzing the measurement data, the authors review the points that should be improved and the technical method for the new maintenance system of membrane tension.

• 한국항공우주학회지
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• 제33권12호
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• pp.33-38
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• 2005

본 연구에서는 팽창형 막 구조물의 대변형 특성을 수치적 그리고 실험적으로 살펴보았다. Miller와 Hedgepeth의 막 이론을 이용하여 주름 효과를 고려한 막재료 구성방정식을 FORTRAN으로 해석 알고리즘을 만들어 user material(UMAT) subroutine을 개발하였다. 개발된 주름 해석 UMAT subroutine을 상용 해석 프로그램 ABAQUS와 연계 해석하여 팽창형 막 구조물의 주름 영역과 변형된 형상 특성 연구를 수행하였다.

• Korean Membrane Journal
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• 제1권1호
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• pp.50-58
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• 1999

Symmetric asymmetric and composite perfluoropolymer membranes made with HYFLON AD have been prepared and evaluated. Porous and non porous symmetric membranes have been prepared by solvent evaporation with various processing conditions. Non-contact atomic force microscopy (AFM) was used to investigate the membrane morphology in air. Analysis of the images gave quantitative imformation on the surface pore strcture in particular on the pore size distributin. Possible useful uses of porous membranes are envisaged in the field of gas-liquid separations such as membrane contactors (MSc) Molecular Dynamics(MD) simulations structure of HYFLON AD 60X copolymer supporting these results are also reported. Amorphous perfluoropolymer membranes appears to be ideal other than in MCs when separation processes have to be performed in hostile environments i.e. high temperatures and aggressive non-aqueous media such as chemicals and solvents. In these cases HYFLON AD mem-branes can exploit the outstanding resistance of perfluoropolymers.

• 한국막학회:학술대회논문집
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• 한국막학회 2000년도 춘계 총회 및 학술발표회
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• pp.47-50
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• 2000

• 멤브레인
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• 제3권3호
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• pp.136-139
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• 1993

It is well known that the membrane permeation in pervaporation is governed by both the chemical nature of the membrane material and the physical structure of the membrane and also the separation can be achieved by differences in either solubility, size or shape. The solubility of the penerrant in the polymeric membrane can be described qualitively by applying the Hildebrand relation [1] which relates the energy of mixing of the penerrant and the polymer material. Froehling et al. have tried to predict the swelling behavior of polymers for the systems of polyvinylchloride(PVC)-toluene-methanol, PVC-trichloroethylene-nitromethane and PVC-n-butylacetate-nitromethane[2]. The former two systems which do not show the donor/acceptor interactions upon mixing showed the successful results[2]. In addition to this technique, there are several other possible approaches to predict the swelling behaviors of polymers, such as the surface thermodynamic approach[3, 4], the comparison of the membrane polarity with the solvent polarity in terms of Dimroth's solvent polarity value[5].

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.649-653
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• 2005

Recently, many membrane structure buildings are constructed with the trend of multi functional and high technological construction. The membrane structure has the characteristics such as distinguished architectural shape which can make variable space creation and can make economic use of material. Therefore, it is in the spotlight of sport complex, various concert hall, and public service buildings. However, the acoustic study of membrane structure has not been following up the increasing demand for the membrane structure. In this study, the acoustic characteristics of membrane structure will be studied and analyzed using architectural acoustic factors based on acoustic design theory And also, the differences between theoretical exhortation value and outcome of study will be studied with the basis of architectural acoustic material study.

• 한국공간구조학회논문집
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• 제10권2호
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• pp.127-134
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• 2010

막 구조는 자유로운 형태, 경량성, 내구성, 햇빛 투광성 및 균질성 때문에 전 세계적으로 현대 건축물에 다양하게 사용되어 왔다. 새로운 막 재료의 개발로 새로운 건축 구조설계에 대한 가능성을 열어가고 있다. 최근 주로 사용되는 막 구조의 지붕 재료에는 PVC, PVF, PVDF, PTFE 코팅 막재 및 ETFE 막재가 수로 사용되고 있다. 건축용 막은 내화성, 강도 부족, 인열강도, 내구성 및 탄성 등에 대한 몇가지 문제점들을 가지고 있다. 이러한 문제점들을 평가하기 위해서 본 연구에서는 PVDF 코팅 폴리에스터 막재에 대한 인장강도, 인열 강도 및 반복하중거동 시험을 실시하여 건축용 막재의 기초적인 역학적 특성을 분석하고자 한다. 막재의 탄성계수는 337.30~1257.63N/$mm^2$, 신율은 17.90~26.91%로 주어졌다.

• 멤브레인
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• 제25권5호
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• pp.456-463
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• 2015

본 연구에서는 고온에서 우수한 전도성을 가지는 전해질막의 개발을 위하여 신규한 실란계 무기물을 합성하였으며, 이를 이용하여 제조된 분리막의 특성평가가 진행되었다. 탄화수소계열 고분자인 SPAES를 합성하여 고분자 물질로 사용하였으며, 높은 이온전도성을 가지는 무기물의 제조를 위하여 silica, phosphate, zironium계 물질을 졸겔법을 이용하여 복합화 시켰다. 각 조성의 몰비를 조절하여 세 가지 종류의 무기물을 제조하였으며 조성에 따른 물성변화를 관찰하였다. EDX 분석결과 제조된 무기물은 고분자 분리막 내에 고르게 분산이 되는 것을 확인하였다. 친수성을 가지는 무기물의 도입을 통하여 분리막 내에 이온을 전달할 수 있는 수분채널이 형성되어 함수율이 증가가 됨을 확인하였다. 또한 zirconium계 무기물의 함량이 높을수록 고온에서 전도도가 향상되는 결과를 확인하였으며 복합화된 실리카는 저온 가습조건에서 이온전도도가 향상되는 결과를 나타내었다.

• 한국막학회:학술대회논문집
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• 한국막학회 2005년도 추계 총회 및 학술발표회
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• pp.96-101
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• 2005

A theory for the material transports through ion exchange membrane has been developed on the basis of nonequilibrium thermodynamics by removing the assumption of solvent flow in the previous paper and applied to a detailed study of the ionic transport properties of new charged mosaic membrane(CMM) system. The CMM having two different fixed charges in the polymer membrane indicated unique selective transport behavior then ion-exchange membrane. The separation behavior of ion transport across the CMM with a parallel array of positive and negative functional charges were investigated. It was well-known the analysis of the volume flux and solute flux based on nonequilibrium thermodynamics. Our suggests preferential salt transport across the charged mosaic membranes. Transport properties of heavy metal ions, $Mg^{2+}$, $Mn^{2+}$and sucrose system across the charged mosaic membrane were estimated. As a result, we were known metal salts transport depended largely on the CMM. The reflection coefficient indicated the negative value that suggested preferential material transport and was independent of charged mosaic membrane thickness.