• 제목/요약/키워드: TETRA

검색결과 596건 처리시간 0.025초

Synthesis of 4-Hydroxy-1-thiocounmarin Derivatives-1 : An Efficient Synthesis of Thioflocoumafen

  • Jung, Jae-Chul;Kim, Ju-Cheun;Park, Oee-Sook;Jang, Bong-Suek
    • Archives of Pharmacal Research
    • /
    • 제22권3호
    • /
    • pp.302-305
    • /
    • 1999
  • An efficient procedure for the preparation of 4-hydroxy-3-{1,2,3,4-tetra-hydro-3-[4-(4-trifluoromethylbenzyloxy)phenyl]-1-naphthyl}thiocoumarin (thioflocoumafen, 1a and 1b) is described. The key step in the synthesis involves the condensation reaction of 3-(4-methoxyphenyl)-1-tetralol (2) with 4-hydroxy-1-thiocoumarin (3).

  • PDF

Chiral separation of $\beta$-blockers after derivatizalion wilh a new chiral derivalizalion agen1.GATC and Comparison wilh GITC on derivalizing conditions and chromalographic paramelers

  • Ko, Mi-Young;Shin, Dae-Hong;Seo, Sang-Hun;Kim, Kyeong-Ho
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
    • /
    • pp.398.1-398.1
    • /
    • 2002
  • A new chiral derivatization agent with sugar moiety. 2, 3.4, 6-tetra-O-acetyl-D-galactopyranosyl isothiocyanate (GATC) was synthesized. Several $\beta$-blockers were investigated for the possible separation of the enantiomers by reversed-phase HPLC after derivatization with this new chiral derivatization agent (GATC). GATC was reacted readily with $\beta$-blockers at room temperature and the reaction mixture could directly be injected into the HPLC system. (omitted)

  • PDF

아크릴계 점착제와 초박형 웨이퍼소재와의 점착특성 - 아크릴 중합체의 측쇄의 영향 - (Adhesion Characteristics of Acrylic Pressure Sensitive Adhesives on Thin Wafer Materials - Effect of Acrylic Copolymer Side Chain -)

  • 유종민;남영희;이승현;김형일;임동혁;김현중;김경만
    • 접착 및 계면
    • /
    • 제10권3호
    • /
    • pp.134-140
    • /
    • 2009
  • 분자설계를 통하여 측쇄를 변화시킨 아크릴공중합체를 합성하여 아크릴공중합체 점착제와 초박형웨이퍼와의 젖음성 및 점착물성을 조사하였다. 선형 아크릴공중합체를 에폭시계 Tetra-DX 가교제와 반응시켜 3차원 망상구조를 형성하고 가교의 영향을 조사하였다. 계면상호작용보다는 아크릴공중합체의 측쇄변화가 젖음성에 더 큰 영향을 미쳤다. 가교도가 증가할수록 probe tack, peel strength가 감소하는 경향을 나타냈다. 가교에 의해 SAFT 내열성이 증가하였지만 가교제의 함량이 증가하면 오히려 SAFT 내열성이 감소하였다.

  • PDF

${\alpha},{\beta}$-tetra(phenoxy, 2-naphthoxy, 4-tritylphenoxy) Oxovanadium 프탈로시아닌 유도체의 합성 및 특성에 관한 연구 (The Study for Synthesis and Characteristic of ${\alpha},{\beta}$-tetra(phenoxy, 2-naphthoxy, 4-tritylphenoxy) Oxovanadium Phthalocyanine Derivatives)

  • 손대희;허진;김송혁;이승호;이근대;홍성수;박성수
    • 공업화학
    • /
    • 제21권6호
    • /
    • pp.638-642
    • /
    • 2010
  • 본 연구에서는 벤젠고리의 ${\alpha}$${\beta}$-위치에 phenoxy, 2-naphthoxy 또는 4-trityl phenoxy 치환기가 도입된 프탈로니트릴 유도체들을 합성하였고, 이들 중간체들을 이용하여 전자 주게 특성을 가지는 치환기가 도입된 oxovanadium phthalocyanine (VOPc) 유도체들을 성공적으로 합성하였다. 시료들의 구조 특성 및 분자량은 $^1H$-NMR, FT-IR 및 MALDI-TOF형 질량분석기를 이용하여 측정 분석하였고, 광학적 및 화학적 특성은 UV-Vis 분광기, X-ray 회절기 및 열분석기를 이용하여 측정 분석하였다. 합성된 VOPc 유도체들의 최대흡수파장 값은 약 684~726 nm이었으며, 치환기의 도입으로 말미암아 용해도가 향상되거나 Q 밴드가 이동하였다.

재난통신 체계에 따른 품질요건 재설계에 관한 연구 (A Study on Re-design of Quality Requirements for Disaster Communication Systems)

  • 양정모;김정호
    • 디지털융복합연구
    • /
    • 제13권10호
    • /
    • pp.327-335
    • /
    • 2015
  • 재난통신망은 TETRA(TErrestrial Trunked RAdio)에서 대용량 데이터 통신이 가능한 광대역 이동통신 기술인 Public Safety-LTE(Long Term Evolution) 자가망을 활용하는 방향으로 발전하고 있다. 국내에서는 재난재해 대응기관 간의 일원화된 통신체계 유지를 위해 재난안전통신망 구축사업을 추진하고 있으나, 재난재해 현장에 위치한 피해당사자와의 통신을 고려하지 않고 재난재해 대응기관 간 지휘통제를 중심으로 통신망을 구축하고 있다. 본 연구에서는 국내 재난통신망 구축동향과 해외 선진사례를 해석하여 전 범위 재난통신망 구축을 위한 쟁점을 도출하고 통신주체와 목적에 따라 재난통신 영역을 새롭게 정의하여 재난통신 영역을 통제통신, 대응통신, 현장통신, 당사자통신, 경보통신으로 세분화하였다. 본 연구를 통하여 재정의 된 재난통신 영역의 특성을 분석하고 이에 따른 핵심 품질요건을 재설계하여 영역별 음영지역 없는 전 범위 재난통신 체계 구축방안을 수립하였다.

P2P1 유한요소를 이용한 LES (Large Eddy simulation using P2P1 finite element formulation)

  • 최형권;남영석;유정열
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집E
    • /
    • pp.386-391
    • /
    • 2001
  • A finite element code based on P2P1 tetra element has been developed for the large eddy simulation (LES) of turbulent flows around a complex geometry. Fractional 4-step algorithm is employed to obtain time accurate solution since it is less expensive than the integrated formulation, in which the velocity and pressure fields are solved at the same time. Crank-Nicolson method is used for second order temporal discretization and Galerkin method is adopted for spatial discretization. For very high Reynolds number flows, which would require a formidable number of nodes to resolve the flow field, SUPG (Streamline Upwind Petrov-Galerkin) method is applied to the quadratic interpolation function for velocity variables, Noting that the calculation of intrinsic time scale is very complicated when using SUPG for quadratic tetra element of velocity variables, the present study uses a unique intrinsic time scale proposed by Codina et al. since it makes the present three-dimensional unstructured code much simpler in terms of implementing SUPG. In order to see the effect of numerical diffusion caused by using an upwind scheme (SUPG), those obtained from P2P1 Galerkin method and P2P1 Petrov-Galerkin approach are compared for the flow around a sphere at some Reynolds number. Smagorinsky model is adopted as subgrid scale models in the context of P2P1 finite element method. As a benchmark problem for code validation, turbulent flows around a sphere and a MIRA model have been studied at various Reynolds numbers.

  • PDF

TEGDME 액체 전해질을 사용한 $Li/MoS_2$ 전지의 충.방전 특성 (The Charge-Discharge Performance of $Li/MoS_2$ Battery with liquid Electrolyte of Tetra(ethylene glycol] Dimethyl Ether[TEGDME])

  • 권정희;류호석;김기원;안주현;정용수;이건환;안효준
    • 한국수소및신에너지학회논문집
    • /
    • 제20권3호
    • /
    • pp.238-244
    • /
    • 2009
  • We investigated the electrochemical properties of lithium/molybdenum sulfide(Li/MoS$_2$) using tetra (ethylene glycol) dimethyl ether(TEGDME) electrolyte. The Li/TEGDME/MoS$_2$ cell showed the first discharge capacity of 288mAhg$^{-1}$. From the XRD, SEM results of the MOS$_2$ electrode in various cut-off voltage during charge-discharge process, MoS$_2$ partly changed into Li$_2$S and Mo during discharge and Li$_2$S partly recovered into MOS$_2$ and Li during charge. Full charged MOS$_2$ electrode showed lump shape of big size, which might be related to agglomerate of MoS$_2$ particles. Therefore, the degradation might be related to decrease of active material for electrochemical reaction by agglomeration of MOS$_2$.

저니토중 Polychlorinated Biphenyls(PCBs) 정량에 관한 연구 (A Study on Quantitation of Polychlorinated Biphenyls (PCBs) in Sediments)

  • 신호상;오윤숙
    • 분석과학
    • /
    • 제12권2호
    • /
    • pp.151-158
    • /
    • 1999
  • 국내 4대강 주요 하천 저니토양중 PCB 오염도를 각 congener별로 또는 총량으로서 GC/MS를 사용하여 정량하였다. 그 결과 4대강의 주요 지천중 SS지점 근처의 저니토에서 총 PCBs가 가장높은 $290.87{\mu}g/kg$이었고 OS지점에서도 비교적 높은 $221.11{\mu}g/kg$이었으며 저니중 유기물 함량과 상관관계가 있었다. Congener-specific analysis에 의해 하천수 및 저니토 시료에서 공통적으로 검출된 대표적 congener는 IUPAC No 66, 74, 90, 101, 105, 110, 118, 138, 149, 153, 180, 187였다. 본 연구결과 저니토에서는 tetraCBs 및 pentaCBs가 다른 polyCBs에 비해 비교적 높은 농도로 검출되었다. 이상의 연구결과를 통해 국내의 주요 하천의 저니토중 PCB의 오염정도는 매우 심각한 정도는 아니나 좀더 많은 시료를 분석하는 정말조사가 필요하다.

  • PDF

급성염증유발 동물모델에서 포공영(蒲公英)의 염증억제 효과 (Anti-inflammatory Activity of Dandelion in Mice)

  • 함대현;서봉준;한동오;박재현;정은택;이혜정;고윤정;최희돈
    • 동의생리병리학회지
    • /
    • 제22권4호
    • /
    • pp.810-814
    • /
    • 2008
  • Most inflammatory disorders are usually treated using anti-inflammatory drugs including non-steroidal anti-inflammatory drugs (NSAID) and steroidal anti-inflammatory drugs (SAID). Prolonged uses of NSAIDs and SAIDs may frequently cause adverse side-effects such as nausea, vomiting, diarrhea, constipation, decreased appetite, kidney and liver failure, ulcers, and prolonged bleeding after an injury or surgery. Thus, it is necessarily required to develop a new anti-inflammatory drug with little side-effects. Dandelion (Taraxacum officinale) possesses the therapeutic abilities to eliminate body heat and toxins and to remove swelling and inflammation. In order to verify the anti-inflammatory activity of dandelion, TPA(12-O-tetra decanoylphorbol-acetate)-induced or croton oil-induced acute edema was developed in the mouse ears, and dandelion extract dissolved in acetone was applied to both sides of inflamed ears. It was found that dandelion could significantly reduce the ear swelling, compared to that of non-treated control. In the case of $20{\mu}{\ell}$ application of $100mg/m{\ell}$ dandelion solution (DA-100), its anti-inflammatory effect was comparable to that of indomethacin, a non - steroidal anti-anflammatory drug. Taken together, it could be concluded that topically applied dandelion extract exhibited its potentials as a new drug candidate with an effective anti-inflammatory activity.

Bryophyllum 3종의 영양기관과 생식기관에서 표피구조와 기공유형 (Epidermal Structure and Stomatal Types in Vegetative and Reproductive Organs of Three Species of Bryophyllum)

  • 정우규
    • Journal of Plant Biology
    • /
    • 제30권1호
    • /
    • pp.43-57
    • /
    • 1987
  • The epidermal structure and stomatal types in vegetative and reproductive organs of three species of Bryophyllum(B. crenatum, B. diagremontion, B. tubiflorum) were described. The epidermal cells were polygonal, isodiametric, and rectangular in the leaves and stems, and elongated cells in the stamens, styles, and ovaries. These cells were commonly thick, and arched or sinuous in the leaves, epiphylous bunds, petals and ovaries. They were straight in the stems, petioles, pedicels, and peduncles. In both vegetative and reproductive organs, the subsidiary cell walls were commonly thin and mostly arched in all the organs. The great majority of the mature stomata in all the organs were helicocytic type with a helix of four to six subsidiary cells. The mature stomata varied from organ to organ with regard to the number and arangement of subsidiary cells. The ontogenetic type of stomata in all the organs was mostly helico-eumesogenous type. This type was subdivided into three subtypes such as parahelico-eumesogenous, anomohelico-eumesogenous, and diahelico-eumesogenous stomata on the basis of the division angle fo the guard mother cell. Sometimes, the anisoeumesogenous type was found in various organs. This type was subdivided into three subtypes such as paraniso-eumesogenous, anomoaniso-eumesogenous, and dianisoeummesogenous stomata. The tetra-eumesogenous and duplotetra-eumesogenous types were rarely found; the former in the leaf of B. crenatum and the latter in the leaf of B. diagremontiana. Anomometric patterns in the mesogenous categorry of stomatal types was observed in a few organs of all the materials. A new stomatal type with tetra-eumesogenous stoma within a girdle of three subsidiary cells fo aniso-eumesogenous in the leaf of B. diagremontiana was firstly observed in the vascular plants. This stoma was termed the cotetra-aniso-eumesogenous type. Anormal stomata such as aborted stomata, single guard cells, stoma with a constricted part in the middle of large guard cells, and arrested stomata were found in the various organs of all the materials.

  • PDF