• Journal of Pharmaceutical Investigation
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• v.4 no.1_2
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• pp.1-6
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• 1974

S-Benzylthiuronium chloride reacts with ethylene glycol, derived from hydrolysis of the fluorides, to produce a crystalline substances. Using this, the fluorides can be indentified by measuring melting point. And when the zirconium-alizarin solution reacts with ethylenefluoro hydrin or ${\beta}-fluoroethyl$ acetate, the red-violet color disappears to produce a yellow dye, which exhibits absorption maximum at about $530\;m{\mu}$ using the 250-microgram standard. Using these properties, the fluorine compounds can be determined conveniently by this method.

• Journal of the Korean Ceramic Society
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• v.26 no.2
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• pp.171-178
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• 1989

In order to develope hydroxyapatite ceramics which has mechanical strength as bio-implant materials and get the basic data for the study and application of biocompatibility, hydroxyapatite was synthesized at Ca/P=1.67~1.75, pH 7~11 by precipitation method. Using prepared powders, the sintered body, fluorine substituted body and the porous body was formed and their properties were investigated. The sample obtained in condition of Ca/P=1.67, pH 7 and sintering at 1,15$0^{\circ}C$ was decomposed to $\beta$-tricalcium phosphate, and co-existed with hydroxyapatite. Hydroxyapatite synthesized at pH 11 was not easily decomposed to $\beta$-tricalcium phosphate at sintering process. The substitution of a small amount of fluorine for hydroxyapatite prevented hydroxyapatite from being decompsed to $\beta$-tricalcium phosphate. Hydroxyapatite ceramics which substited of 10% fluorine was prepared at 1,15$0^{\circ}C$, and the valueof bending strength for this body were found to be 112MPa.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.383-386
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• 1998

After etching Al-Cu alloy films using SiC1$_4$/Cl$_2$/He/CHF$_3$ plasma, a corrosion phenomenon on the metal surface has been studied with XPS (X-ray photoelectron spectroscopy) and SEM (Scanning electron microscopy). In Al-Cu alloy system, the corrosion occurs rapidly on the etched surface by residual chlorine atoms. To prevent the corrosion, CHF$_3$ plasma treatment subsequent to the etched has been carried out. A passivation layer is formed by fluorine-related compounds on the etched Al-Cu surface after CHF$_3$ and SF$_{6}$ treatment, and the layer supresses effectively the corrosion on the surface as the CHF$_3$ and SF$_{6}$ treatment pressure increases. The corrosion could be suppressed successfully with CHF$_3$ and SF6 treatment in the pressure of 300mTorr.orr.

• Journal of dental hygiene science
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• v.10 no.6
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• pp.439-443
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• 2010

The purpose of this study was to prevent excessive use of fluorine toothpaste. To comparatively evaluate the amount used of the fluorine toothpaste in children from 3 to 6 years old, the toothpaste amount was compared according to toothbrush size and toothpaste squeezing method targeting 84 children in 5 child care centers where were located in Hongseong-gun, Chungnam. The toothpaste amount was compared with a method of squeezing to pea-size and a method of smear on toothbrush, targeting 141 students for the Dept. of Dental Hygiene, who are actually carrying out oral health education to targeting children. The statistical analysis was used SPSS 14.0 K for Windows program(Copyright(c) SPSS Inc.). The following results were obtained. 1. The amount of fluorine toothpaste squeezed on toothbrush for children was 0.29 g. The amount of fluorine toothpaste squeezed on toothbrush for adults was 0.34 g. It was surveyed to use the less amount of toothpaste when squeezing to smaller toothbrush (p<0.05). 2. The amount that children aged 3-6 squeezed as the method of squeezing commonly at ordinary times was 0.31g. The amount that was squeezing to pea-size was 0.21 g. The amount that was squeezed by using smear method was measured to be 0.26g. Less amount of fluorine toothpaste was used with the method of squeezing to pea-size and smear method rather than a method of squeezing commonly at ordinary times(p<0.05). 3. As a result of surveying the students of the department of dental hygiene, the amount of having squeezed to pea- size was 0.23 g. It was surveyed to be 0.15 g when having used the smear method. Thus, it was surveyed to use the less amount of toothpaste when using the smear method(p<0.05). 4. Using smaller toothbrush, the amount used of fluorine toothpaste can be reduced. Both smear method and the method of squeezing to pea-size are available for minimizing careless fluorine intake by less used amount of fluorine toothpaste.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.2
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• pp.91-99
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• 2009

Noninvasive imaging of molecular and biological processes in living subjects with positron emission tomography(PET) provides exciting opportunities to monitor metabolism and detect diseases in humans. Measuring these processes with PET requires the preparation of specific molecular imaging probes labeled with $^{18}F$-fluorine. In this review we describe recent methods and novel trends for the introduction of $^{18}F$-fluorine into molecules which in turn are intended to serve as imaging agents for PET study. Nucleophilic $^{18}F$-fluorination of some halo- and mesyloxyalkanes to the corresponding $^{18}F$-fluoroalkanes with $^{18}F$-fluoride obtained from an $^{18}O(p,n)^{18}F$ reaction, using novel reaction media system such as an ionic liquidor tert-alcohol, has been studied as a new method for $^{18}F$-fluorine labeling. Ionic liquid method is rapid and particularly convenient because $^{18}F$-fluoride in $H_2O$ can be added directly to the reaction media, obviating the careful drying that is typically required for currently used radiofluorination methods. The nonpolar protic tert-alcohol enhances the nucleophilicity of the fluoride ion dramatically in the absence of any kind of catalyst, greatly increasing the rate of the nucleophilic fluorination and reducing formation of byproducts compared with conventional methods using dipolar aprotic solvents. The great efficacy of this method is a particular advantage in labeling radiopharmaceuticals with $^{18}F$-fluorine for PETimaging, and it is illustrated by the synthesis of $^{18}F$-fluoride radiolabeled molecular imaging probes, such as $^{18}F$-FDG, $^{18}F$-FLT, $^{18}F$-FP-CIT, and $^{18}F$-FMISO, in high yield and purity and in shorter times compared to conventional syntheses.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.265-267
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• 2002

섬유를 제조함에 있어 기존의 방법으론 수 마이크론의 섬유를 만들지만 전기방사를 이용한 방법으로는 마이크론이하의 직경을 가진 섬유를 만들수 있어 전기방사에 관한 관심이 증가하고 있다. 전기방사란 고분자 용액 및 용융된 고분자에 고전압을 걸어주어 섬유를 받아주는 콜렉터와 방사되는 팁 사이에 전기장을 형성시켜 부직포를 제조하는 방법이다. 일반적으로 불소를 포함한 방향족 고분자는 그들의 구조 때문에 외부열에 대한 저항력, 내화학성, 기계적, 전기적 특성이 우수하다고 잘 알려져 있다. (중략)

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.49.1-49.1
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• 2007

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.155-156
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• 2000

We propose a new in-situ fluorine passivation of poly-Si TFTs by excimer laser annealing to reduce the trap density and improve the reliability significantly. This improvement is due to the formation of stronger Si-F bonds than Si-H bonds which passivate the trap states.

• Journal of the Korean Chemical Society
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• v.29 no.3
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• pp.252-256
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• 1985

Absolute infrared intensities are predicted for the vibrational bands of gas-phase SiF$_2$ using a fluorine atomic polar tensor transferred from various fluorine compounds. The predicted relative intensities agree well with published spectra of gas-phase SiF$_2$.

• YAKHAK HOEJI
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• v.16 no.2
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• pp.108-112
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• 1972

S-Trifluoroacetoxy-trihalomethyl mercaptans were prepared by reacting metal salt of trihaloacetic acid with perhalomethyl mercaptans in the closed vessel. And besides, certain decomposed states of these products by heat and U.V. were studied by Infra red, N.M.R., molecular weight determination and chemical analysis methods. The results showed that the more fluorine substituted compounds were more stable than the less fluorine substituted ones.