• 제목/요약/키워드: membrane penetration

검색결과 137건 처리시간 0.031초

조경 녹화용 방수.방근층의 방근 성능평가 시험방법에 관한 연구 - 모의 바늘과 지하경을 이용한 방근 성능평가 시험방법 - (A Study on Test Method for Evaluating Root Resistance in Waterproofing and Root Resistance Membrane Used in Landscape Architecture - A Test Method for Evaluating Root Resistance that Use a Simulated Needle and a Rhizome -)

  • 이준호;표순주;신진학;오상근
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2009년도 춘계 학술논문 발표대회 산업계
    • /
    • pp.89-97
    • /
    • 2009
  • As landscaping building roofs and concrete structures increase gradually for low carbon green growth policy of government, But waterproofing membranes of those structures are effecting by root penetration of landscape plant. 80, we progressed study about test method for fast evaluating root resistance of waterproofing materials jointly with Tokyo Institute of Technology. The result of the study is as follows: (1) The penetrating load of the needle at the displacement speed of 1mm/min was measured for various membrane to basis and lap joints of membrane, the load force was $3{\sim}50$ N by material variously. (2) According to the test method of deriving rhizomes of bamboo grass to basis and lap joints of membrane, there were no penetrated membrane until present, but need persistent observation. (3) Test method of deriving rhizomes of bamboo grass to basis and lap joints of membrane can shorten from period of 2 years to 1 year for testing. Because rhizomes of bamboo grass can grow from May to September, test is possible in same period.

  • PDF

The Unique Mechanism of SNX9 BAR Domain for Inducing Membrane Tubulation

  • Park, Joohyun;Zhao, Haiyan;Chang, Sunghoe
    • Molecules and Cells
    • /
    • 제37권10호
    • /
    • pp.753-758
    • /
    • 2014
  • Sorting nexin 9 (SNX9) is a member of the sorting nexin family of proteins and plays a critical role in clathrinmediated endocytosis. It has a Bin-Amphiphysin-Rvs (BAR) domain which can form a crescent-shaped homodimer structure that induces deformation of the plasma membrane. While other BAR-domain containing proteins such as amphiphysin and endophilin have an amphiphatic helix in front of the BAR domain which plays a critical role in membrane penetration, SNX9 does not. Thus, whether and how SNX9 BAR domain could induce the deformation of the plasma membrane is not clear. The present study identified the internal putative amphiphatic stretch in the $1^{st}$ ${\alpha}$-helix of the SNX9 BAR domain and proved that together with the N-terminal helix ($H_0$) region, this internal putative amphiphatic stretch is critical for inducing membrane tubulation. Therefore, our study shows that SNX9 uses a unique mechanism to induce the tubulation of the plasma membrane which mediates proper membrane deformation during clathrinmediated endocytosis.

Preparation and Characterization of New Immunoprotecting Membrane Coated with Amphiphilic Multiblock Copolymer

  • Kang, Han-Chang;Bae, You-Han
    • Macromolecular Research
    • /
    • 제10권2호
    • /
    • pp.67-74
    • /
    • 2002
  • New immunoprotecting membranes were prepared by spin coating the amphiphilic random multiblock copolymers of poly(ethylene glycol) (PEG) and poly(tetramethylene ether glycol) (PTMEG) or poly(dimethyl siloxane) (PDMS) on porous Durapore(R) membrane. The copolymer coating was intended to make a biocompatible, immunoprotecting diffusional barrier and the supporting porous substrate was for mechanical stability and processability. By filling Durapore(R) membrane pores with water, the penetration of coating solution into the pores was minimized during the spin coating process. A single coating process produced a completely covered thin surface layer (~1 ${\mu}{\textrm}{m}$ in thickness) on the porous substrate membrane. The permselectivity of the coated layer was influenced by PEG block length, polymer composition, and thickness of the coating layer. A composite membrane with the coating layer prepared with PEG 2 K/PTMEG 2 K block copolymer showed that its molecular weight cut-of fat any 40 based on dextran was close to the molecular size of IgG (Mw = 150 kDa). However, IgG permeation was detected from protein permeation test, while glucose oxidase (Mw = 186 kDa) was not permeable through the coated membrane.

바나듐계 레독스 흐름 전지용 고분자 이온교환막의 연구개발 동향 (Research Trend of Polymeric Ion-Exchange Membrane for Vanadium Redox Flow Battery)

  • 김득주;남상용
    • 멤브레인
    • /
    • 제22권5호
    • /
    • pp.285-300
    • /
    • 2012
  • 바나듐 흐름전지는 오랜 사이클 수명, 높은 에너지효율, 낮은 제조단가 그리고 친환경성으로 인하여 에너지저장장치의 한 부분이 될 것으로 기대되고 있다. 바나듐 흐름전지 시스템의 핵심 부품의 하나로서 이온교환막은 이온이 계속적으로 전달되는 동안 양극과 음극 전해질의 투과를 저해하는 물성이 요구된다. 그러나 Nafion과 같은 이온교환막은 넓은 시장성의 확보를 위한 목표성능의 달성을 위한 몇가지 과제들에 직면하고 있다. 그러므로 이러한 문제들을 해결하기 위하여 최근까지 개발된 여러가지 이온교환막에 대하여 Nafion과 비교하여 바나듐 흐름전지특성에 대하여 조사하였다.

[P(AA-co-PEGMM)] 공중합체 필름으로부터 Butorphanol Tartrate의 구강점막 투과 특성 및 투과촉진제의 검색 (Transport Characteristics and Screening of Penetration Enhancer through Buccal Mucosa of Butorphanol Tartrate from [P(AA-co-PEGMM)] Copolymer Films)

  • 김준식;박정숙;정연복;한건
    • Journal of Pharmaceutical Investigation
    • /
    • 제33권3호
    • /
    • pp.157-162
    • /
    • 2003
  • The feasibility of [P(AA-co-PEGMM)] film as a buccal mucoadhesive patch was previously reported by estimating mucoadhesiveness and release characteristics. To find a rational penetration enhancer of [P(AA-co-PEGMM)] film containing butorphanol tartrate (Bt), penetration of Bt from [P(AA-co-PEGMM)] film which contained various additives was estimated by measuring its flux, Papp and lag tme in in vitro buccal membrane of porcine. EDTA showed almost no increase of Bt permeability, wherease SGC, STDHF and SLS increased the permeability of Bt with the order of SGC > STDHF > SLS. The rational additive concentration of SGC was 4% and its Papp and lag time were $1.93{\times}10^{-4}{\pm}4.21{\times}10^{-6},\;126.60{\pm}21.88min\;(control\;:\;Papp\;0.45{\times}10^{-4};\;lag\;time\;211.01{\pm}16.77\;min)$, respectively.

Hairless Mouse와 Pig Skin을 활용한 약물 투과성 비교 (Comparison of Drug Delivery using Hairless Mouse and Pig Skin)

  • 조완구
    • 한국응용과학기술학회지
    • /
    • 제24권4호
    • /
    • pp.410-415
    • /
    • 2007
  • Functional cosmetics are intensively investigated for the effectiveness of skin whitening, anti-aging and slimming. For enhancing the effectiveness, active ingredients should be delivered into the cell in the dermis. The amounts of penetration of caffeine and $Arbutin^{(R)}$ were tested, in vitro, using Franz diffusion cell. Oil-in-water emulsions were used for the vehicles of the transport. For the measuring the amounts of active ingredients delivered into the dermal skin, tape stripping was done after finishing the penetration experiments. The amounts of delivered caffeine were $8.45{\pm}$ 1.26ug/ml before tape stripping and $3.45{\pm}$ 1.80ug/ml after tape stripping, however, the amounts of delivered $Arbutin^{(R)}$ was quite small to detect. From now on, proper vehicles are considered for enhancing the delivery of $Arbutin^{(R)}$ Hairless mouse skin was compared with pig skin as a transdermal delivery membrane. The aspects of delivery were similar, but the amount of delivered ingredients using pig skin was larger than that of using hairless mouse skin. Therefore, the pig skin would be considered as a membrane for drug delivery experiments.

Investigation for the physio-chemical stabilities of Idebenone encapsulated with non-hydrous skin analogue membrane and its transdermal penetration

  • Jeong, Kwan-Young;Lee, Dong-Kyu
    • 한국응용과학기술학회지
    • /
    • 제25권3호
    • /
    • pp.313-321
    • /
    • 2008
  • 오래전부터, 많은 여성들은 자신들의 젊음을 연장하고, 외모를 더 아름답게 가꾸고, 이를 죽을 때까지 유지하는 것을 바래왔다. 이에 의사와 약사들뿐만 아니라, 많은 화장품 연구자들도 노화와 관련된 기술개발에 총력을 기울여 왔다. 따라서, 이들 연구자들은 노화방지를 위한 새로운 원료를 찾고, 이를 안정화하고, 피부로 전달하는 기술개발에 항상 관심을 쏟아왔다. 뛰어난 노화방지 화장품 개발을 위해서, Ubiquinone의 일종인 ldebenone에 대해 연구하였고, 이를 비수계 피부유사막 기술을 가지고 캡슐화하고 약물전달하는 연구를 진행하였다. 먼저, 편광현미경(PM, Polarized Microscope), X-선 회절분석(XRD, X-ray Diffractions) 및 시차주사열량계 (DSC, Differential Scanning Calorimetry)를 이용하여 Idebenone을 담지한 피부유사막 액정을 비수계 조건에서 구조 및 열적특성을 조사하였다. 그 결과 비수계 조건에서도 규칙적으로 패킹(Packing)된 지질이중층(Lipid bilayer)과 용매의 연속층으로 이루어진 고밀집된 라멜라(Lamella) 구조의 형성유무와 이때의 상거동을 확인할 수 있었다. 결론적으로 높은 극성도로인해 물분자와 접촉하면 불안정해지는 경향이 있는 Idebenone을 비수계 조건에서 각질층(SC, Stratum Corneum)과 구조 및 조성이 유사한 피부유사막을 디자인하여 안정하게 캡슐화 하였다. 이를 적용한 화장품은 모든 보관조건에서 유화입자의 안정성을 유지함을 확인하였고, Idebenone의 활성역가 또한 $40^{\circ}C$에서 6개월 동안 약 90%이상을 유지하는 우수한 결과를 나타냈다.

율촌 복합화력발전소 공내 재하 시험 (Pressuremeter Test in YULCHON Combined Cycle Power Plant)

  • 이용길;박경호
    • 한국지반환경공학회 논문집
    • /
    • 제2권1호
    • /
    • pp.5-13
    • /
    • 2001
  • 본 논문의 목적은 율촌 복합화력발전소 부지에 대한 지지력 산정 및 지반 특성 파악을 위한 공내재하시험의 결과를 분석하는 것이다. 율촌 복합화력발전소 부지는 인근의 야산 토취장에서 매립토를 채취 운반하여 강제치환공법으로 성토하였으며, 지질은 상부로부터 산토, 준설매립해성점토, 실트집모래, 원지반해성점토층, 풍화대, 풍화암, 연암의 순으로 존재한다. 공내재하시험은 해성점성토층을 제외한 토층에 대하여 토층의 특성에 따라 각각 다른 크기의 Probe와 Membrane을 사용하여 수행하였으며, 콘시험과의 상관성, 내부 마찰각과의 관계 및 토질 특성을 파악하였다.

  • PDF

페녹시기와 카르복시레이토페녹시기가 함께 치환된 포스파젠 고분자를 이용한 당뇨병 진단막의 제조 (Preparation of Diabetic Diagnostic Membranes with Phenoxy-Carboxylatophenoxy Cosubstituted Polyphosphazenes)

  • 권석기
    • 멤브레인
    • /
    • 제27권2호
    • /
    • pp.138-146
    • /
    • 2017
  • 새로운 형태의 페녹시-카르복시레이토페녹시기가 함께 치환된 포스파젠 고분자를 여러 치환율을 가지고 합성하였다. 이러한 형태의 포스파젠 고분자를 이용해 당뇨병 진단막을 제조하여 혈액 속의 글루코우즈의 농도를 변화시켜가며 680 nm에서의 흡광도를 측정하였다. 기본적으로 흡광도가 시간에 따라 변화하는 양(K/S)과 글루코우즈의 농도가 직선적인 관계를 가지는 것으로 나타났다. 소수성기인 페녹시기와 친수성기인 카르복시레이토페녹시기의 치환율이 글루코우즈 농도 측정에 미치는 영향을 조사하였다. 친수성기의 치환율이 10% 이하인 경우에는 글루코우즈의 침투속도가 너무 느려 글루코우즈의 농도 측정이 어려웠다. 그러나 친수성기의 치환율이 10% 이상으로 증가함에 따라 글루코우즈의 농도와 K/S의 기울기 값(Dose-Response Slope : DRS)이 점차 증가하였다. 하지만 친수성기의 치환율이 30% 이상일 경우에는 글루코우즈가 너무 빨리 침투하여 DRS가 급격히 증가하였다.

티타늄강화 차폐막의 골유도 재생 효과 (Osteopromotive effect of Titanium Reinforced-ePTFE membrane)

  • 이진;권영혁;박준봉;허익;정종혁;김종관
    • Journal of Periodontal and Implant Science
    • /
    • 제34권4호
    • /
    • pp.711-722
    • /
    • 2004
  • The purpose of this study is to evaluate the regenerated bone histollogically using titanium reinforced ePTFE(TR-ePTFE) membrane and to investigate cell occlusiveness, wound stabilization and tissue integration of TR-ePTFE membrane. Adult male rabbits (mean BW 2kg) and TR9W (W.L.Gore&Associate.INC,USA) were used in this study. Intramarrow penetration defects were surgically created with round carbide bur(HP long #6) on calvaria of rabbits. TR-ePTFE membrane was applied to defect. Then guided bone regeneration was carried out using TR-ePTFE membrane and resorbable suture. At 2,4,8,12 weeks after the surgery, animals were sacrificed. Nondecalcified specimens were processed for histologic analysis. The result and conclusion of this study were as follows: 1. TR-ePTFE membrane had good ability of biocompatibility and cell occlusiveness. 2. space making for guided bone regenerayion was good at TR-ePTFE membrane. 3. Tissue integration was not good at TR-ePTFE membrane. So, wound stabilization was not good. 4. At 8 weeks, 12 weeks after GBR procedure, bone formation was seen. From the above results, TR-ePTFE membrane fixed tightiy on alveolar bone might be recommended for the early bone formation.