• 제목/요약/키워드: Characteristics of solvent

검색결과 677건 처리시간 0.031초

Preparation and release characteristics of PVP-based solid dispersion capsules containing solubilizers

  • Cao, Qing-Ri;Kim, Tae-Wan;Choi, Choon-Young;Lee, Beom-Jin
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.412.1-412.1
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    • 2002
  • Purpose. To prepare PVP-based solid dispersions containing lovastatin (LOS) and solubilizers (sodium lauryl sulfate. Tween80. oleic acid) to enhance dissolution of practically insoluble LOS. Methods. Solid dispersions containing LOS were prepared by dissolving two different organic solvent systems (acetone/ethanol or acetonitrile/ethanol). Results. The stickiness and flowability of solid dispersion powders were dependent on the composition and ratio of the solubilizers. (omitted)

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HATM 수지의 합성 및 기계적 특성에 관한 연구 (A Study on the Synthesis and Mechanical Characteristics of NATM Resin)

  • 김기준
    • 한국응용과학기술학회지
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    • 제22권4호
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    • pp.355-361
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    • 2005
  • The physical characteristics of polyurethane were examined by SEM, FT-IR tensile strength and mole % [NCO/OH]. Growing concerns in the environment-friendly architecture and public works have led to the development of solvent-free formulations that can be cured and foamed in air. Compared with general packing materials, this resin is much stronger in intensity and much longer in durability. Polyurethane foam resins were mainly composed of polyol, MDI, silicone surfactant, fillers, catalyst and blowing agent. The rigid foam of polyurethane in mechanical characteristics were due to chain extender and the increase of mole % [NCO/OH]. The change in the microstructure of polyurethane should be taken into account when considering the process of construction and durability through the polyurethane polymer resin in lots of industries.

모래에 침지시킨 방향족 유기용제의 연소특성 (Combustion Characteristics of Immobilized Aromatic Organic Solvent in Sands)

  • 우인성;황명환;정덕채
    • 한국안전학회지
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    • 제15권3호
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    • pp.83-87
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    • 2000
  • Combustion characteristics of immobilized benzene and toluene in sands were studied. Experiments were performed by burning benzene and toluene immobilized on sands(particle size 0.1~0.5mm) to measure combustion rate and combustion temperature. The longer time from ignition to extinguishment was resulted from the larger particle size exhibited the higher mass burning rate. Of aromatic compounds tested the relative magnitude of facilitation of combustion was benzene and toluene. Combustion temperature of benzene and toluene without regard to the types of benzene and toluene was not increased with smaller sand. However, with larger sands, combustion temperature of benzene and toluene were increased by 50~$100^{\circ}C$ and the highest combustion temperature was obtained with larger sands.

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항생물질 생산 Streptomyces의 분리 및 동정에 관하여 (On the Isolation of Antibiotic Producing Streptomyces spp. from Soil)

  • 서용만;홍순우
    • 미생물학회지
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    • 제15권2호
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    • pp.93-99
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    • 1977
  • Among the Streptomyces isolated from soil, two strains which have antibacterial activity aginst various pathogenic bacteria are identified as Streptomyces globosus and Streptomyces albus subsp. according to I.S.P. methods and Bergy's Manual of Determinative Bacteriology. Morphological and physiological characteristics of them on several media were observed. Antibiotics from S. albus subsp. or S. globosus was identified asw tetracycline or streptomycin-like substances respectively by the paper chromatographic behavior in eight solvent systems of V. Betina. And it was revealed that these antibiotic substances are stable to temperature and weak acid.

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전기 이중층 커패시터 적용을 목적으로 한 공용매상 전해액과 전기화학적 특성 (Enhance Potential Stability of Organic Electrolyte in EDLC by Using Co-solvent and Its electrochemical properties.)

  • 이현석;육영재;김한주;박수길
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2014년도 추계학술대회 논문집
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    • pp.164-164
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    • 2014
  • Characteristics of electrolyte are those; electrical stability, ion conductivity, viscosity, high temperature work, cell application. Theoretically, GBL has high oxidation voltage. Also, boiling point of GBL is $206^{\circ}C$ and flash point is over $280^{\circ}C$.

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유리고분자의 용매전달특성 및 그 해석 (Solvent Transport Characteristics of Glassy Polymers and its Analysis)

  • 김덕준
    • 멤브레인
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    • 제8권1호
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    • pp.11-21
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    • 1998
  • The study on penetrant transport in glassy polymers has been actively pursued for decades because of its growing significance in polymer processing and related applications such as not only membranes, but corrosion protective coatings, microlithography, microelectronic fabrication, etc. In membranes application of polymeric materials, successful utilization requires understanding of how solvents penetrate, swell, and sometimes dissolve polymeric materials under various environmental conditions, as their permselecdve performance is significantly affected by it. The expose of polymer membranes to solvents may result in the structural failure due to mechanical softening, embrittlement or crazing.

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Roll to Roll Printing용 전도성 Paste 물성 연구 (A Study on the Characteristics of Conductive Paste for Roll-to-Roll Printing)

  • 조미정;남수용
    • 한국인쇄학회:학술대회논문집
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    • 한국인쇄학회 2007년도 추계 학술논문 발표회
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    • pp.59-64
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    • 2007
  • We have manufactured low-curable silver pastes for gravure printing out of roll to roll printing process. When printing, the pastes be used different silver powder shape because of the printing characteristics. The pastes were prepared with silver powder by silver powder shape, polyester resin, solvent and homogenized on a standard three-roller mill. And the pastes exhibited a shear-thinning flow at viscosity profile. Moreover the adhesive strength and resistivity of silver film had good characteristics. With the manufactured paste in this study, RFID antenna circuit had flexible is manufactured and it had $10^{-4}{\sim}10^{-5}{\Omega}{\cdot}cm$.

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LPE에 있어서 InP 기판의 열손상 상태와 Melt Back 특성 (Thermal Damages and Melt Back Characteristics of InP Substrate in the LPE Growth)

  • 조호성
    • 한국광학회:학술대회논문집
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    • 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.206-209
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    • 1989
  • It has been that, above $600^{\circ}C$, a cover crystal is essential for protecting InP substrate from severe gas etching during soaking procedure and shown that the melt back rate of substrate crystal in In solvent is about 0.90${\mu}{\textrm}{m}$/sec at 635$^{\circ}C$, 0.57${\mu}{\textrm}{m}$/sec at 615$^{\circ}C$ and 0.37${\mu}{\textrm}{m}$/sec at 595$^{\circ}C$.

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CIGS nanopowder 제조 및 특성분석 (Preparation and Characteristics of CIGS nanopowder)

  • 함창우;서정대;조정민;송기봉
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
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    • pp.371-372
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    • 2009
  • We have prepared and characterized CIGS nanopowder for absorber layer of photovoltaic. CIGS nanopowder were obtained at $260^{\circ}C$ for 6 hours from the reaction of $CuCl_2$, $InCl_3$, $GaCl_3$ and Se powder in solvent. The CIGS nanopowder were identified to have a typical chalcopyrite tetragonal structure by using X-ray diffraction(XRD), Inductively Coupled Plasma Auger Electron Spectroscopy (AES), Scanning Electron Microscopy(SEM).

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분할형 극세사 직물의 흡용제특성 (Organic solvent absorption characteristics of split-type micro fiber fabrics)

  • 이광주;김성훈
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2003년도 봄 학술발표회 논문집
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    • pp.313-314
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    • 2003
  • 분할형 극세사 직물은 서로 상용성을 가지지 않는 nylon/polyester의 용융고분자물을 복합방사법에 의하여 filament 형태로 방사한 후 이를 제직, 편성의 방법으로 포를 제조하고 알칼리 용액에 처리함으로써 생산되어 진다. 따라서 극세사 직물은 일반적으로 소수성의 합성섬유로 이루어졌음에도 불구하고 알칼리 가수분해에 의하여 분할된 섬유 사이의 수많은 모세관에 의하여 높은 흡수성과 수분전이능력을 갖게 된다. 이러한 이유로 극세사 직물은 일반적인 와이퍼의 용도뿐만이 아니라 food service, medicine, 반도체를 제조하는 clean room등으로 그 응용범위를 넓혀 가고 있다. (중략)

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