• 한국환경과학회지
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• 제12권3호
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• pp.319-324
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• 2003

The characteristics of photocatalytic decomposition of dye waste water by titanium dioxide was studied in a batch reactor under constant strength of ultra-violet ray. The decomposition rate of methyl orange by TiO$_2$ was pseudo-first order, anatase type TiO$_2$ was more effective than rutile type below the dosage of 5g. The decomposition rate was increased with decreasing initial pH, increasing reaction temperature and oxidant concentration. The decomposition rate of water soluble dyes was decreased in order of rhodamine B>eosin Y>methyl orange.

• 한국응용과학기술학회지
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• 제12권2호
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• pp.145-150
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• 1995

The Kinetics velocity for hydrolysis reaction of vanillylidene imine derivatives has been measured by ultra-violet ray spectrophotometer in 20wt% $dioxane-H_2O$ at $25^{\circ}C$. It was measured the reaction rate Constant of vanillylidene imine derivatives that can be applied widely following to pH-change at $25^{\circ}C$. Final products that hydrolyzed the vanillylidene imine certified in vanillin and aniline derivative, and the effect of substitution radical that has affected on hydrolysis reaction was largely promoted to reaction rate by electron attrating group in acidity and electron donoring group in basic. From the results of rate constant to hydrolysis reaction, substituent radical effect and final products. It has certified the hydrolysis reaction mechanism of vanillylidene imine derivatives.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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• pp.422-424
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• 2000

ZnO thin films for light emission device have been deposited on sapphire and silicon substrates by pulsed laser deposition technique(PLD). A Nd:YAG laser was used with the wavelength of 355 nm. In order to investigate the emission properties of ZnO thin films, PL measurements with an Ar ion laser as a light source using an excitation wavelength of 351 nm and a power of 100 mW are used. All spectra were taken at room temperature by using a grating spectrometer and a photomultiplier detector. ZnO exhibited PL bands centered around 390, 510 and 640 nm, labeled near ultra-violet (UV), green and orange bands. Structural properties of ZnO thin films are analized with X-ray diffraction (XRD).

• 조명전기설비학회논문지
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• 제28권4호
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• pp.16-20
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• 2014

To prevent any accident in electric power utilities, many researches for inspection and diagnosis deteriorations occurring by corona discharges have been continuously studying. Inspection and diagnosis of electric power utility is very important to prevent an accident. This paper studies a measurement of ultra-violet(UV) ray of corona discharges on polymer insulators using an UV sensor array with an optic lens. The detection of an UV signal begins at 60kV, which is about 37.5% of the breakdown voltage of the polymer insulator and the stronger the high voltage increased to the polymer insulator was. It can be determined that the polymer insulator mounted on a live part must be examined when the discharge risk exceeds approximately 40%. In conclusion, the status of power utilities can be checked using an UV sensor.

• Advances in nano research
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• 제13권5호
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• pp.437-451
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• 2022

Synthesis approaches usually affect the physical and chemical properties of ferrites. This helps ferrite materials to design them for desired applications. Some of these methods are mechanical milling, ultrasonic method, micro-emulsion, co-precipitation, thermal decomposition, hydrothermal, microwave-assisted, sol-gel, etc. These methods are extensively reviewed by taking example of ZnFe₂O₄. These methods also affect the microstructure and local structure of ferrite which ultimately affect the physical and chemical properties of ferrites. Various spectroscopic techniques such as Raman spectroscopy, Fourier Transform Infrared spectroscopy, Ultra Violet-Visible spectroscopy, Mossbauer spectroscopy, extended x-ray absorption fine structure, and electron paramagnetic resonance are found helpful to reveal this information. Hence, the basic principle and the usefulness of these techniques to find out appropriate information in ZnFe₂O₄ nanoparticles is elaborated in this review.

• 한국전기전자재료학회논문지
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• 제16권12호
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• pp.1091-1096
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• 2003

Ion implantation in polymeric materials can induce dramatic chemical modifications, such as bond breaking, cross linking, formation of new chemical products, which have strong influences on the macroscopic properties of the materials. In this study ion implantation was performed onto polymer, PC(polycarbonate), in order to investigate change of the optical transmittance property focusing ultraviolet ray range(200-400nm). PC was irradiated with N, Ar, Kr, Xe ions at the ion energy of 50keV and the dose range of 5 ${\times}$ 10$\^$15/, 1 ${\times}$ 10$\^$16/, 7${\times}$10$\^$16/ ions/$\textrm{cm}^2$. FT-IR, XPS, UV/Vis transmittance spectroscopy measurement technologies were employed to obtain chemical. structural properties and optical transmittance of irradiated polymer. The original PC(unimplanted) is quite transparent that it has more than 88% transmittance in the range UV-A(320∼400nm), but after ion implantation, surface colors were changed to the dark brown and the transmittance of UV ray decreased for all implantation condition, and the absorption edge was shift to visible range with increasing mass of implanted ion species and dose.

• The Journal of Korean Physical Therapy
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• 제13권3호
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• pp.561-567
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• 2001

IR classified by wavelength three parts NIR, MIR. FIR. There is FIR which is radiated from healthy human body the wave length is 8-14m. The Sun's ray is composed of Infared(49%), Visible light(40%) and Ultra violet(11%), however the ray getting to the earth is FIR(60%), IR(20%), and UV(20%). Human beings has utilized FIR already from time immemorial. Hershel found out Infrared for the first time, in the Industrial Revolution the Infrared and FIR had been begun to use making products. FIR with low temperature can deeply penetrate on the human body composed things without troublesome, since FIR has effectively operated on the human body at low temperature (35-40 $^{\circ}$C). In this study, we experimented in the specific temperature FlR radiation intensity. water consumption rate, feed consumption rate. survival rate and mean of weight balance with FlR radiation instrument. According to the results, the FlR radiation to the mice assisted to increase the survival rate.

• The Journal of Korean Physical Therapy
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• 제13권1호
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• pp.189-195
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• 2001

The Sun's ray is composed of Infared(49%), Visible light(40%) and Ultra violet(11%), however the ray getting to the earth is FIR(60%). IR(20%), and UV(20%). Human beings has utilized FIR already from time immemorial. Hershel found out Infrared for the first time, in the Industrial Revolution the Infrared and FI R had been begun to use making products. In asia. also, asian already has made use of FIR to treat the body, product things and make warm the house in the winter, as it had been called Wull therapy, fermentation. and On-Dol system. In these days, with contemporary science FIR would be begun to clear up the implication in the human body and organic compounds. IR classified by wavelength three parts NIR, MIR, FIR. There is FIR which is radiated from healthy human body the wave length is 8-14 m. It is difficult to standardized the wavelength of IR, since each related associations have a different opinion, so we suggested ideal IR wavelength and biological, phsiotherapical, medical FIR wavelength.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 제2회 학술대회 논문집 일렉트렛트 및 응용기술전문연구회
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• pp.50-55
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• 2000

In this paper, Thermally Stimulated Current(TSC) spectrum has been measured in oriented polypropylene of thickness of $40{\mu}m$ which was irradiated by Ultraviolet Ray. As a result of the investigation, four peaks have been observed-two peaks ($A_1$, $A_2$) were appeared in low temperature region($-20{\sim}20^{\circ}C$) and other two peaks ($B_1$, $B_2$) in high temperature region($80{\sim}120^{\circ}C$). Among four peaks $A_1$ and $A_2$ have bee observed in detail. These peaks are shown to be created due to the polarization of diploes from the experimental results which were measured as a function forming voltage, forming time, collecting voltage and heating rate. As the increase of irradiated-time by Ultraviolet ray, the number of dipoles was increased.

• 한국전기전자재료학회논문지
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• 제19권8호
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• pp.744-748
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• 2006

Emission characteristics of terbium-activated $InBO_3$ under cathode-ray(c.r.) and vacuum ultra violet(v.u.v.) irradiation have been investigated as a functions of norminal compositions and firing conditions. From the x-ray analysis, it was found that some of the synthesized samples contained excess $In_2O_3$ and the amount of the excess $In_2O_3$ varied with the norminal composition and heat treatment conditions. The samples with remanent excess $In_2O_3$ showed lower luminescence intensities than the ones free of excess $In_2O_3$. The phosphors of norminal composition of $InBO_3+10mol%B_2O_3:2mol%Tb$ synthesized at $1250^{\circ}C$ showed excellent CL and PL properties.