• 제목/요약/키워드: C₃F/sub 8/

검색결과 212건 처리시간 0.031초

Surface Order of Hexagonal Columnar Mesophases Induced by Molecular Assembly

  • Kim, Sang-Ouk;Ko, Young-Koan;Yoon, Dong-Ki;Kang, Sang-Yoon;Jung, Hee-Tae
    • KIEE International Transactions on Electrophysics and Applications
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    • 제11C권2호
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    • pp.32-36
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    • 2001
  • We investigate the surface order, defects and morphology of hexagonal columnar mesophases, Having a crown ether at one end which forms the center of the column and three fluorinated tails at the other, The orientation of the columns was successfully controlled by surface anchoring: Columns were aligned perpendicularly to an evaporated carbon surface, and the planar alignment do asymmetric compounds was induced by a water surface. TEM images show that there is a high degree of perfection in the packing do the cylinders. The hexagonal columnar mesophase (F(sub)h) was confirmed by direct images and the corresponding electron diffractions, where ordered cylindrical moieties are packed on a hexagonal lattice. The column of 12F8-ABG-15C5 was much straighter, compared with that of 12F8-AG-B15C5, resulting from the degrees of regular stacking. Elementary edge dislocation, grain boundary and +1/2 disclination have been observed, although the defects are generally rare.

Characterization of Surface Modified Polysulfone Membranes with Various Fluorine Chemicals

  • Lee, Choong-Sub;Rhim, Ji-Won
    • Korean Membrane Journal
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    • 제4권1호
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    • pp.20-24
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    • 2002
  • The surface of polysulfone membranes has been modified using the fluorine chemicals, ITFE (2-iodo-1,1,1-trifluoro-ethane F.W.=209.94) and PFPI (1H,1H-pentafluoro-n-propyl iodide F.W.=259.95), and PFI (1H,1H,2H,2H-perfluorohexyl iodide, F.W.=373.99) based on Friedel-Crafts reaction mechanism with varying reaction temperatures, reaction time, and catalysis types. The resulting membranes were characterized through mainly the contact angle measurement and pure water permeability. The smaller reactant shows the larger contact angles. FeBr$_3$ catalyst is more effective than AlCl$_3$. Typically, the PS film treated with ITFE at $25^{\circ}C$ under FeBr$_3$ catalyst showed the contact angle 78.5$^{\circ}C$ which indicated 10% over the value of unreacted PS films. More than 50% of pure water flux 8.0 g/$m^2$hr, reduced at reaction time 10 min relative to the original flux, 3.49 g/$m^2$hr.

일대잡종 분화용 나팔나리 'Bright LoSong' 육성 (Breeding of Lilium longiflorum 'Bright LoSong' as a F1 Hybrid for Pot)

  • 송천영;문자영
    • 현장농수산연구지
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    • 제23권2호
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    • pp.25-32
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    • 2021
  • 우리나라에서 재배되고 있는 백합 구근의 대부분을 수입에 의존하고 있어 국내 품종을 개발하여 보급할 필요가 있다. 분화용 나팔나리 유전자원 'Ace', 'Nelli White'를 수집하여 1996년부터 2010년까지 자가수정을 실시하였다. 2012년에 자가수정 7세대 'L2-17-4' 과 'L2-16-6' 계통을 교잡하여 1대잡종 나팔나리 'Bright LoSong'를 개발하였다. 'Bright LoSong'은 균일성 및 지역성응성 검정은 바탕으로 2014년부터 2015년까지의 품평회를 통하여 선발하여 품종 등록은 2017년에 되였다. 분화용 나팔나리 일대잡종 'Bright LoSong'는 백색의 나팔모양의 홑꽃으로 반점이 없으며, 식물체 당 개화수가 5.8개로 많은 편이며, 꽃의 직경은 9.8cm이고 측향으로 개화한다. 초장은 38.4cm이고, 잎의 수는 30.8개이고, 잎의 길이는 14.9cm이며, 잎의 폭은 1.9cm이다. 일대잡종 'Bright LoSong'는 대조품종인 'Mount Carmel' 보다 화수가 많아서 개화 기간이 길며 소비자 선호도가 높다. 일대 잡종 'Bright LoSong'은 실내에서 재배가 원활하여 분화용으로 선호도가 우수하며 양친을 순계화하여 육성하였기 때문에 품종의 재현이 가능하다.

고리 이합체 2,3-비스(2-피리딜)피라진(트라이플루오르아세테이토)은(I) 착물의 합성 및 결정 구조 (Synthesis and Crystal Structure of Cyclodimetric Ag(I) Complex with 2,3-Bis(2-pyridyl)pyrazine)

  • 김은주;이영아;이욱;정옥상
    • 한국결정학회지
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    • 제11권1호
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    • pp.28-33
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    • 2000
  • The slow of 2,3-bis(2-pyridyl)pyarzine(bpp) with Ag(CF₃CO₂) produces crystalline product suitable for X-ray crystallography. Crystallographic characterization of the crystal (C/sub 32/H/sub 20/-F/sub 6/N/sub 8/O₄Ag₂: triclinic P1, a=8.518(5)Å, b=9.546(2)Å, c=10.632(1)Å, α=81.11(1)°, β=87.61(3)°, γ=75.66(3)°, V=827.5(5)ų, Z=1, R=0.0431) has provided that the complex is a cyclic dimer [Ag(bpp)(CF₃CO₂)]₂. Each bpp ligand connects two tetrahedral silver(I) ions in a tridentate mode (Ag-N, 2.26()-2.43(2)Å), and the trifluoroacetato anion is bonded to each silver(I) atom in a monodentate fashion (Ag-O, 2.38(1); 2.39(2) Å). The skeletal cyclic dimer is stable up to 212℃, and drastically decomposes around this temperature.

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용액환원법에 의한 Sn02 2차원 나노구조의 합성과 가스 감응 특성 (Sn02 Two-dimensional Nanostructures Prepared by Solution Reduction Method and Their Gas Sensing Characteristics)

  • 박홍철;김해룡;이종흔
    • 한국재료학회지
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    • 제18권8호
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    • pp.438-443
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    • 2008
  • SnO nanosheets were prepared at room temperature through a reaction between an aqueous solution of $SnCl_2$, $N_2F_4$, and NaOH and were converted into $SnO_2$ nanosheets without a morphological change. The SnO nanosheets were formed through a dissolution-recrystallization mechanism. Uniform and well-dispersed SnO nanosheets with the round-shape morphology were attained when the solution was treated by ultrasonic sound immediately after the addition of NaOH. The $SnO_2$ nanosheets prepared by means of solution reduction under the ultrasonic treatment, and subsequent oxidation at $600^{\circ}C$ showed a high level of gas sensitivity to $C_2H_5OH$ and $CH_3COCH_3$.

Cytotoxic Activity of 13(E)-Labd-13-ene-8$\alpha$, 15-diol

  • Lim Jin A;Kwang Jung Sook;Yu Byung Soo;Baek Seung Hwa
    • 동의생리병리학회지
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    • 제18권4호
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    • pp.1169-1172
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    • 2004
  • The cytotoxic activity of 13(E)-labd-13-ene-8α, 15-diol (1) was evaluated against tumor cell lines. A comparison of IC/sub 50/ values of this compound in cancer cell lines showed that their susceptibility to this compound decreased in the following order: P388>B16{F10>MDA-MB-231>A549>KB>SNU-C4 by the MTT method. 13(E}-Labd-13-ene-8α, 15-diol (1) was the most effective growth inhibitor of P388 murine leukaemia cell lines, producing approximately 8.3㎍/mL of IC/sub 50/ in the MTT method.

초임계 유체 염색용 염료에 따른 면 섬유의 염색 특성 : C.I. Disperse orange 155, C.I. Disperse red 167 (A Study of Dyeing Properties of Cotton Fabrics Under Supercritical CO2 Depending on Dyestuff : by C.I. Disperse orange 155, C.I. Disperse red 167)

  • 최현석;김훈민;전태영
    • 한국염색가공학회지
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    • 제34권2호
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    • pp.93-101
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    • 2022
  • In this study, the dyeing properties of supercritical fluid dyed cotton fabrics were investigated which use two types of dyes, such as C.I. Disperse orange and C.I. Disperse red 167. Dyeing temperature, pressure and leveling time were equally applied at 130 ℃, 250 bar, and 60 minutes with reference to the related literature, and experiments were performed at concentrations of 0.04, 0.1, 0.4 and 0.8 % o.w.f with different concentrations. Dyeability was confirmed through measurement of washing fastness and color coordinate, and a calibration curve of each dye was drawn up and the absorbance of the residual dye was measured to confirm the amount of residual dye and the dye exhaustion rate at the corresponding concentration. As a result of color difference measurement, as the concentration increased, the L* value decreased and the K/S value increased. However, as the concentration increased, the increase in K/S value decreased compared to the input amount, and this tendency was more obvious in C.I. Disperse red 167 than in C.I. Disperse orange 155. The dye exhaustion rate which was calculated by using the amount of residual dye in the pot was also C.I. Disperse orange 155 was 96.16 % and C.I. Disperse red 167 was 94.57 %. However, as the dyeing concentration increased, the dye exhaustion rate decreased, that C.I. Disperse orange was 95.33 % and C.I. Disperse red 167 was 90.63 %. As a result of the washing fastness test for both dyes, dyed samples of which concentrations were 0.4 and 0.8 % o.w.f decreased by 0.5 ~ 1.0 grade. This is predicted because the dye did not completely adhere to the amorphous region of the cotton fiber and the dye simply adsorbed. The fastness to rubbing also maintained at least grade 3-4 up to the 0.1 % o.w.f concentration, but at the concentration of 0.4 % o.w.f or higher, it fell to grade 1 or lower, showing a very poor friction fastness.

적정간호수가 산정모형 개발을 위한 연구 (Development of a Nursing Fee Schedule Model)

  • 조소영;박정호
    • 대한간호학회지
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    • 제23권1호
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    • pp.68-89
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    • 1993
  • This study was conducted to develop a model of a fee schedule for nursing services.'Regardless of the demand for skilled and professional nursing service today, the Korean health insurance system does not furnish a chapter for the nursing service fee schedule. A nation-wide survey of hospital nursing service fee schedules was to provide practical and realistic data about how the variety of nursing services are being charged. From September 1990 to April 1991, data from the fee schedule used by twenty hospitals located in eight large cities which are designated large medical regions in the Korea Health Care and Patient Referral System were collected. Nursing services and the fees charged for them were analyzed. The nursing services were subjected to a secondary analysis with referrence to reports on “nursing services to be charged in Korea”. The total number of nursing services recommended by the literatures was 177 : finally 141 types of nursing services were selected by investigator as chargable nursing services. In addition, data on managerial characteristics of the hospitals were collected to discover influential variables for a nursing fee schedule model. Under the assumption that all the managerial characteristics of the hospitals influenced the fee schedule, the following model was tested : Fee of nursing services (C) = f(A₁, A₂, A₃, A₄, A/sub 5/, A/sub 6/, A/sub 7/, A/sub 8/,) When, A₁ = number of nurses A₂ = the first salary of a nurse educated in a four year A₃ = scale of nursing management division A₄ = location of the hospital A/sub 5/ = the type of hospital management (profit / non-profit) A/sub 6/ = number of hospital beds A/sub 7/ = years of hospital operation A/sub 8/ = number and kinds of clinical divisions The results showed that the model should be built as follows : C = f (A₁, A/sub 4/, A/sub 5/) Each nursing service was applied to the fee schedule with consideration for the professional level and time-taken to provide the services. Detailed fee schedules were presented in the related tables. Of the 141 kinds of nursing services, 24.8% were chargeble to the Korea Health Insurance, 32.6% of the nursing services were being paid directly by the patienty. The rest of nursing services (42.6%) were not being charged to any source. It was recommened that the Korea Health Insurance Reimbursement system should add a classification system for nursing services that can be used in the national health care program. Further study is needed about how to include 32.6% of the nursing services now being paid for directly by the patients in the health insurance system.

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Phase Evolution, Microstructure and Microwave Dielectric Properties of Zn1.9-2xLixAlxSi1.05O4 Ceramics

  • Kim, Yun-Han;Kim, Shin;Jeong, Seong-Min;Kim, So-Jung;Yoon, Sang-Ok
    • 한국세라믹학회지
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    • 제52권3호
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    • pp.215-220
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    • 2015
  • Phase evolution, microstructure, and microwave dielectric properties of $Li_2O$ and $Al_2O_3$ doped $Zn_{1.9}Si_{1.05}O_4$, i.e., $Zn_{1.9-2x}Li_xAl_x-Si_{1.05}O_4$, ceramics (x = 0.02 ~ 0.10) were investigated. The ceramics were densified by $SiO_2$-rich liquid phase composed of the Li-Al-Si-O system, indicating that doped Li and Al contributed to the formation of the liquid. As the secondary phase, ${\beta}$-spodumene solid solution with the composition of $LiAlSi_3O_8$ was precipitated from the liquid during the cooling process. The dense ceramics were obtained for the specimens of $$x{\geq_-}0.06$$ showing the rapid densification above $1000^{\circ}C$, implying that a certain amount of liquid is necessary to densify. The specimen of x = 0.06 sintered at $1050^{\circ}C$ exhibited good microwave dielectric properties; the dielectric constant and the quality factor ($Q{\times}f_0$) were 6.4 and 11,213 GHz, respectively.

Effects of Fertilizer Treatment on the Growth Performance of 1-Year-Old Containerized Seedlings in Chionanthus retusus

  • Choi, Chung Ho
    • 한국자원식물학회지
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    • 제33권6호
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    • pp.586-596
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    • 2020
  • Chionanthus retusus has been used for landscaping and gardening trees, foods and medicines. This study was carried out to analyze the effect of fertilization on the growth performance of container seedlings (1-year-old) in C. retusus. We used multifeed 19 (MF) as a fertilizer, and measured the height, root collar diameter (RCD), biomass, seedling quality index (SQI) chlorophyll contents and chlorophyll fluorescence of the seedlings. The findings of this paper showed that the height, RCD, H/D ratio, T/R ratio and the fresh and dry weight of seedlings increased after fertilization. The moisture content of the stem and root did not show any significant difference among fertilizations, except in the case of the leaf. Production distribution such as the dry weight ratio of leaves and the stem dry weight ratio of fertilized seedlings had a higher value than that of non-treatment. SQI was the highest in MF 1,000 mg/L and 2,000 mg/L treatment. Chlorophyll contents (SPAD value) also increased with the increase in fertilization concentrations. Chlorophyll fluorescence (Fv/Fm) showed the highest value of 0.8 in MF 2,000 mg/L treatment.