• Title/Summary/Keyword: modified polypropylene

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20대 여성을 위한 새로운 체표면적 산출식에 관한 연구 (A Study of the New Body Surface Area Calculation for Twenties Women)

  • 임순
    • 복식문화연구
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    • 제7권2호
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    • pp.275-288
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    • 1999
  • The purpose of this is providing a simple, relatively errorless body surface area calculation. Subjects were 10 married women and 10 singles women whose age was 20 to 29 years old. The Gypsum method has applied for the sampling of body surface. The Weight method has been used to measure body surface by means of transferring gypsum shape on uniform plane polypropylene films. In this study, compare analyzed errors between the traditional formulas for measuring body surface area and measuring data in this experiment. More than all, it has been to induce a regression equation for measuring body surface area, which is so simple to calculate with less errors, with variable factors as weight and height. The results of this experiment as follows : 1. In the traditional formulas, weight formula was shown high average error : Niya\`s height formula. which was modified K value as 0.62 in the height formula (S = KH) is shown lower average error than Lassabliere\`s Height formula. 2. In the weight-height formula (S=K √WH), it was shown high average error according to the increasing of K value. Kawanami\`s formula, which 5.378 as K value, was shown low average error both the singles and the married women. 3. Dubois weight-heingt formula (S=W/sup a/·H/sub b/·K) was shown low average error than the weight, height, weight-height (S=K√WH) formula. 4. The regression equations with variable factors as weight and height are 156.74W + 86.05H - 660.25 (Single women) and 136.02W + 90.57H - 6241.32 (Married women) the average error and absolute average error to the singles are 0.09%, 0.94% and resoectively -0.13%, 1.16% for the married women.

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Induced Death of Escherichia coli Encapsulated in a Hollow Fiber Membrane as Observed In Vitro or After Subcutaneous Implantation

  • Granicka, L. H.;Zolnierowicz, J.;Wasilewska, D.;Werynski, A.;Kawiak, J.
    • Journal of Microbiology and Biotechnology
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    • 제20권1호
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    • pp.224-228
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    • 2010
  • The encapsulation of bacteria may be used to harness them for longer periods of time in order to make them viable, whereas antibiotic treatment would result in controlled release of therapeutic molecules. Encapsulated Escherichia coli GFP (green fluorescent protein) (E. coli GFP) was used here as a model for therapeutic substance - GFP fragments release (model of bioactive substances). Our aim was to evaluate the performance of bacteria encapsulated in hollow fibers (HFs) treated with antibiotic for induction of cell death. The polypropylene-surface-modified HFs were applied for E. coli encapsulation. The encapsulated bacteria were treated with tetracycline in vitro or in vivo during subcutaneous implantation into mice. The HF content was evaluated in a flow cytometer, to assess the bacteria cell membrane permeability changes induced by tetracycline treatment. It was observed that the applied membranes prevented release of bacteria through the HF wall. The E. coli GFP culture encapsulated in HF in vitro proved the tetracycline impact on bacteria viability and allows the recognition of the sequence of events within the process of bacteria death. Treatment of the SCID mice with tetracycline for 8 h proved the tetracycline impact on bacteria viability in vivo, raising the necrotic bacteria-releasing GFP fragments. It was concluded that the bacteria may be safely enclosed within the HF at the site of implantation, and when the animal is treated with antibiotic, bacteria may act as a local source of fragments of proteins expressed in the bacteria, a hypothetical bioactive factor for the host eukaryotic organism.

월동 배추의 저온 저장 중 포장 및 적재 방법에 따른 품질 변화 (Quality Changes of Winter Chinese Cabbage by different Packing and Loading during Cold Storage)

  • 김병삼;김민정;김의웅;김건희
    • 한국식품저장유통학회지
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    • 제8권1호
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    • pp.30-36
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    • 2001
  • 월동배추(품종 : 동풍)를 $0^{\circ}C$에서 저온저장중 선도 유지를 위하여 포장과 적입방법 개선에 대한 효과가 조사되었다. 저장과정중 배추의 상품성을 보았을 때 월동배추는 $0^{\circ}C$에 저온 저장한 경우 4개월 이상 저장, 출하가 가능한 것으로 여겨졌다. 포장용기간 저장성은 0.03mm 폴리에칠렌 플라스틱필름에 4포기씩 세로로 적입하여 플라스틱콘테이너에 저장한 경우가 기존의 폴리프로필렌 그물망과 철제파레트를 이용한 경우에 비하여 우수하게 나타났다. MAP 저장시 포장내의 가스 조성은 처리구간에 큰 유의적인 차이를 나타내지는 않았는데 대체로 산소 농도는 8.2~19.5% 정도, 이산화탄소는 0.35~8.58% 범위를 나타내었다. 저온저장중 비타민C, 환원당, 클로로필 색소는 계속 감소하였으며 폴리에틸렌 플라스틱필름과 콘테이너에 의한 MAP가 기존 저장방법에 비하여 10~20% 정도 선도 저하를 억제하는 효과를 가져왔다.

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불화 실리카로 개질된 폴리에테르이미드 중공사막을 이용한 혐기성 유출수로부터 바이오가스 회수 (PEI Hollow Fiber Membranes Modified with Fluorinated Silica Nanoparticles for the Recovery of Biogas from Anaerobic Effluents)

  • 윤강희;수니 웡치피몬;배태현
    • 멤브레인
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    • 제30권5호
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    • pp.326-332
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    • 2020
  • 본 연구에서는, 혐기성 처리수에 용해된 바이오가스의 회수를 위해 불화 실리카/고분자 중공사 복합막을 제조하고 막접촉기에서의 성능을 평가하였다. 복합막은 상용 폴리에테르이미드인(PEI) Ultem®을 이용하여 만든 중공사막 표면에 불화 실리카를 강력한 공유 결합을 통해 코팅하는 방법으로 제조되었다. 막접촉기는 바이오가스로 포화된 수용액을 중공사의 외부에 공급하고, 중공사 내부로 기체를 투과시키는 방법으로 운전하였다. 높은 공극률을 가진 중공사막(PEI-fSiO2-A)은 액상 속도가 0.03 m/s일 때 메탄 회수 유량이 8.25 × 10-5 ㎤ (STP)/㎠·s에 달했고 불화 실리카에 의해 표면 소수성이 매우 높아져 물과의 접촉각이 75.6°에서 120~122°로 향상되었다. 본 연구에서 제조된 복합막은 바이오가스의 투과 속도와 소수성 모두에서 탈기용으로 제조된 상용 폴리프로필렌 막보다 우수한 성능을 나타냈다.

Development of Long-Term Storage Technology for Chinese Cabbage - Physiological Characteristics of Postharvest Freshness in a Cooler with a Monitoring and Control Interface

  • Lim, Ki Taek;Kim, Jangho;Chung, Jong Hoon
    • Journal of Biosystems Engineering
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    • 제39권3호
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    • pp.194-204
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    • 2014
  • Purpose: The aim of this study was to develop long-term storage technology for Chinese cabbage in order to extend the period of availability of freshly harvested products. The scope of the paper deals with the use of a cooler with a remote monitoring and control interface in conjunction with use of packaging film. Methods: A cooler with a real time monitoring system was designed as a low-temperature storage facility to control temperature and relative humidity (RH). The effects of storage in high-density polyethylene (HDPE) plastic boxes, 3% chitosan dipping solution, polypropylene film (PEF) with perforations, and mesh packaging bags on physiological responses were investigated. The optimal storage temperature and humidity for 120 days were below $0.5^{\circ}C$ and 90%, respectively. Physiological and biochemical features of cabbage quality were also analyzed: weight loss, texture, and sugar salinity, chlorophyll, reducing sugar, and vitamin C contents. Results: The cooler with a remote monitoring and control interface could be operated by an HMI program. A $0.5^{\circ}C$ temperature and 90% humidity could be remotely controlled within the cooler for 120 days. Postharvest freshness of Chinese cabbages could be maintained up to 120 days depending on the packaging method and operation of the remote monitoring system. In particular, wrapping the cabbages in PEF with perforations resulted in a less than a 5% deterioration in quality. This study provides evidence for efficient performance of plastic films in minimizing post-harvest deterioration and maintaining overall quality of cabbages stored under precise low-temperature conditions with remote monitoring and a control interface. Conclusions: Packaging with a modified plastic film and storage in a precisely controlled cooler with a remote monitoring and control interface could slow down the physiological factors that cause adverse quality changes and thereby increase the shelf life of Chinese cabbage.

Characterization of an Extracellular Lipase in Burkholderia sp. HY-10 Isolated from a Longicorn Beetle

  • Park, Doo-Sang;Oh, Hyun-Woo;Heo, Sun-Yeon;Jeong, Won-Jin;Shin, Dong-Ha;Bae, Kyung-Sook;Park, Ho-Yong
    • Journal of Microbiology
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    • 제45권5호
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    • pp.409-417
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    • 2007
  • Burkholderia sp. HY-10 isolated from the digestive tracts of the longicorn beetle, Prionus insularis, produced an extracellular lipase with a molecular weight of 33.5 kDa estimated by SDS-PAGE. The lipase was purified from the culture supernatant to near electrophoretic homogenity by a one-step adsorption-desorption procedure using a polypropylene matrix followed by a concentration step. The purified lipase exhibited highest activities at pH 8.5 and $60^{\circ}C$. A broad range of lipase substrates, from $C_4\;to\;C_{18}$ p-nitrophenyl esters, were hydrolyzed efficiently by the lipase. The most efficient substrate was p-nitrophenyl caproate ($C_6$). A 2485 bp DNA fragment was isolated by PCR amplification and chromosomal walking which encoded two polypeptides of 364 and 346 amino acids, identified as a lipase and a lipase foldase, respectively. The N-terminal amino acid sequence of the purified lipase and nucleotide sequence analysis predicted that the precursor lipase was proteolytically modified through the secretion step and produced a catalytically active 33.5 kDa protein. The deduced amino acid sequence for the lipase shared extensive similarity with those of the lipase family 1.2 of lipases from other bacteria. The deduced amino acid sequence contained two Cystein residues forming a disulfide bond in the molecule and three, well-conserved amino acid residues, $Ser^{131},\;His^{330},\;and\;Asp^{308}$, which composed the catalytic triad of the enzyme.

음이온성 유화제로 수식된 폴리락티드/글리코리드 공중합체 나노 입자와 백신의 결합성 (Binding of Vaccine and Poly(DL-lactide-co-glycolide) Nanoparticle Modified with Anionic Surfactant)

  • 최민수;박은석;지상철;신병철
    • Journal of Pharmaceutical Investigation
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    • 제34권3호
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    • pp.177-183
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    • 2004
  • Recently, studies on intranasal mucosa delivery of influenza vaccine have been actively developed because of lack of pain and ease of administration. We studied on preparation of nanoparticle delivery system using biodegradable polymer as a poly(DL-lactide-co-glycolide) (PLGA) and their binding characteristics with vaccine. Three kinds of PLGA nanoparticles were prepared by spontaneous emulsification solvent diffusion (SESD) method using sodium dodecyl sulfate and sodium laurate as an anionic surfactant and Lutrol F68 (polyethylene glycol-block-polypropylene glycol copolymer) as a nonionic surfactant. The 5-aminofluorescein labeled vaccine was coated on the surface of nanoparticles by ionic complex. The complexes between vaccine and nanoparticles were confirmed by change of the size. After vaccine coating on the surface of anionic nanoparticles, particle size was increased from 174 to 1,040 nm. However the size of nonionic nanoparticles was not more increased than size of anionic nanoparticles. The amount of coated vaccine on the surface of PLGA nanoparticles was $14.32\;{\mu}g/mg$ with sodium dodecyl sulfate, $12.41\;{\mu}g/mg$ with sodium laurate, and $9.47{\mu}g/mg$ with Lutrol F68, respectively. In conclusion, prepared nanoparticles in this study is possible to use as a virus-like nanoparticles and it could be accept in the field of influenza vaccine delivery system.

술폰산기를 갖은 코아-쉘형 폴리올레핀 부직포의 전기화학적 성질 (Electrochemical Properties of Core-Shell Polyolefin Nonwoven Fabric Modified with Sulfonic Acid Group)

  • 최성호;;;이광필
    • 분석과학
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    • 제17권1호
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    • pp.60-68
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    • 2004
  • 폴리올레핀 부직포는 녹는점이 ${\sim}162^{\circ}C$며 구성비가 40%인 폴리프로필렌과 녹는점이 ${\sim}132^{\circ}C$며 구성비가 60%인 폴리에틸렌으로 구성된것을 이용하였다. 전지격막을 제조하기 위하여 방사선그래프트 법을 이용하여 이 폴리올레핀에 스틸렌을 그래프트 시킨 후 다음으로 술폰산기를 도입하였다. 술폰산기를 갖은 폴리올페핀 부직포를 XPS, SEM, DSC, TGA, 및 Porosimeter를 사용하여 특성 평가 하였다. 술폰화 반응후, 폴리올레핀 부직포에 대한 전해질 보존 (electrolyte retention), 전기저항 (electrical resistance) 및 $K^+$에 대한 운반율과 같은 전기화학적 특성을 조사하였다. 그 결과 술폰산기의 함량이 증가하면 할수록 전해질 보존율은 증가하였으며 반면에 전기저항은 감소하는 사실을 알았다. 또한 술폰산기의 함량이 0.22 ~ 3.60 mmol/g에서 $K^+$의 운반율은 0.90 ~ 0.93이었다.

잔류응력을 고려한 섬유 금속 적층판의 기계적 물성치 예측에 관한 이론적 연구 (Analytical Study for the Prediction of Mechanical Properties of a Fiber Metal Laminate Considering Residual Stress)

  • 강동식;이병언;박으뜸;김정;강범수;송우진
    • 소성∙가공
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    • 제23권5호
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    • pp.289-296
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    • 2014
  • Uniaxial tensile tests were conducted to accurately evaluate the in-plane mechanical properties of fiber metal laminates (FMLs). The FMLs in the current study are comprised of a layer of self-reinforced polypropylene (SRPP) sandwiched between two layers of aluminum alloy 5052-H34. The nonlinear tensile behavior of the FMLs under in-plane loading conditions was investigated using both numerical simulations and a theoretical analysis. The numerical simulation was based on finite element modeling using the ABAQUS/Explicit code and the theoretical constitutive model was based on the volume fraction approach using the rule of mixture and a modification of the classical lamination theory, which incorporates the elastic-plastic behavior of the aluminum alloy and the SRPP. The simulations and the model are used to predict the inplane mechanical properties such as stress-strain response and deformation behavior of the FMLs. In addition, a post-stretching process is used to reduce the thermal residual stresses before uniaxial tensile testing of the FMLs. Through comparison of both the numerical simulations and the theoretical analysis with the experimental results, it is concluded that the numerical simulation model and the theoretical approach can describe with sufficient accuracy the actual tensile stress-strain behavior of the FMLs.

'후지' 사과의 단기 저온저장 및 모의수출 과정에서 소포장의 천공도 조절 효과 (Perforation Adjustment of Unit Package for 'Fuji' Apples during Short-term Cold Storage and Export Simulation)

  • 김수정;박윤문;윤태명
    • 원예과학기술지
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    • 제32권2호
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    • pp.184-192
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    • 2014
  • '후지' 사과의 단기 저장과 모의 수출 과정에서 소포장 적용이 중량감소와 품질에 미치는 영향을 분석하기 위해 2년에 걸쳐 포장의 밀폐도를 단계적으로 조절하는 실험을 수행하였다. 포장의 밀폐도는 천공 처리 수준(무천공, 펀치 홀, 핀홀)과 밀봉 방식(끈 묶음, 열 접착)을 달리하여 조절하였다. 수확 후 사과를 $40{\mu}m$ 폴리프로필렌 필름 포장 봉지에 5개씩 담아 $0^{\circ}C$에서 4주 저장한 후, 1년차 예비실험에서는 바로 상온유통 과정을 거쳤고 2년차 본 실험에서는 2주간의 냉장 컨테이너 수출 운송과 현지 상온 유통 7일의 모의 수출 과정을 거쳤다. 천공 처리 없이 끈 묶음 혹은 열 접착한, 비교적 높은 수준의 밀폐 소포장에서는 이산화탄소 축적에 의한 내부갈변 증상이 발현되었다. 이에 비해 천공 처리 필름 소포장에서의 MA 환경조성은 핀홀 처리 소포장에서만 관찰되었고, 모든 처리에서 내부갈변 장해는 발생하지 않았다. 밀폐도가 낮은 펀치 홀 천공 처리 필름 소포장에서도 단기 저장 후 모의 수출 과정에서 중량 감소를 줄이는 효과가 나타났으나 과일의 이화학 품질에 미치는 영향은 미미하였다. 천공도를 낮춘 핀홀 처리 역시 이화학 품질 유지 효과는 없었으나 조직감 관능 유지에 효과가 있는 것으로 나타났다. 따라서 사과의 단기저장과 수출과정에 소포장 기술을 적용할 때 MA 조성을 통한 품질유지 효과를 높이기 위해서는 펀치 홀 천공보다는 훨씬 미세한 천공 처리의 필요성이 제시되었다.