• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.318-321
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• 2007

CdSe nanoparticles were prepared by chemical solution methods using $CdCl_2{\cdot}4H_2O$ (or $Cd(NO_3)_ 2{\cdot}4H_2O$) and $Na_2SeSO_3$. The characteristics of CdSe nanoparticles were controlled by the react ion time, reaction temperature and reaction method as well as the surfactants. Cetyltrimethyl ammonium bromide(CTAB) was used as a capping agent to control the chemical reactions in aqueous solution. Polyvinylalcohol(PVA) was used as a templet in sono-chemical method. CdSe nanoparticles synthesized in aqueous solution showed homogeneous size distribution with relatively stable surface. CdSe nanoparticles synthesized in non-aqueous solution containing diethanolamine(DEA) showed the structure transformation from cubic to hexagonal as the reduction temperature increased from 80 to $160^{\circ}C$. Core shell CdSe was synthesized by sono-chemical method. Characteristics of CdSe nanoparticles were analyzed using transmission electron microscopy(TEM), x-ray photoelectron spectroscopy(XPS), x-ray diffraction(XRD), UV-Vis absorption spectra, fourier transform infrared spectroscopy(FT-IR) and photoluminescence spectra spectroscopy(PL). This paper presents simple routes to prepare CdSe nanoparticles for solar cell applications.

• 한국환경농학회지
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• 제14권3호
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• pp.338-344
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• 1995

현미중 카드뮴의 분석을 위한 보다 효율적인 방법을 찾기 위해 현미중 카드뮴의 공정시험방법을 표준으로 수종의 습식 및 건식방법에 대해 카드뮴의 회수율, 표준편차 및 표준방법과의 상관성등을 비교, 검토한 결과 현미 시료량 50g, 회화온도 $600^{\circ}C$의 건식방법은 회수율이 79.6%로 표준분석방법(87.2%)을 제외한 타 분석방법보다 높고, 표준편차도 평균${\pm}2.6$으로 표준분석방법의 평균+6.4 보다 약간 작았으며, 표준분석방법으로 분석된 카드뮴함량과의 상관성($r=0.977^{\ast\ast}$)도 크게 높아 본 방법은 습식으로 분해하는 현행 수질오염 공정시험 방법과 함께 현미중 카드뮴 분석방법으로 사용하여도 좋을 것으로 판단된다.

• 한국잠사곤충학회지
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• 제40권1호
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• pp.17-22
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• 1998

To investigate the detoxificative effect of tea, five kinds of tea(mulberry, anaerobic treated mulberry, green, barly tea and corm tea) were selected and determined their dotoxication activities for Cd and Pb in drinking water. The effect of tea on the removal of Cd and Pb were increased proportionally to the contents of teas. Anaerobic treated mulberry leaf tea showed stronger detoxication activity than the others. In drinking water contaminated with Cd, the removal effect of Cd was high 27% by anaerobic treated mulberry leaf tea and 14% by mulberry leaf tea as compared to green tea. Also, in drinking water with Pb, the removal effect of anaerobic treated mulberry leaf tea was the best among five kinds of tea. Pretreatment method on the removal effect of Cd was better than post-treatment method in the treatment method.

• Journal of Pharmaceutical Investigation
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• 제24권2호
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• pp.85-94
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• 1994

Inclusion complexes of ketoconazole (KT) with ${\alpha}-$, ${\beta}-cyclodextrin$ (CD) and dimethyl-${\beta}-cyclodextrin$ $(DM{\beta}CD)$ in a molar ratio of 1:2 were prepared by freeze-drying and solvent evaporation methods. The interactions of KT with ${\alpha}-CD$, ${\beta}-CD$ and $DM{\beta}CD$ in aqueous solution and in solid state were investigated by solubility study, infrared (lR) spectroscopy and differential scanning calorimetry (DSC). The stability constant of $KT-DM{\beta}CD$ inclusion complex (lC) was found to be the largest among three inclusion complexes. Clear differences in IR spectra and DSC curves were observed between inclusion complexes and physical mixtures (PM) of KT-CDs. It was also shown by IR spectra and DSC curves that solvent evaporation method might be. superior to the freeze-drying method in preparing the inclusion complexes of KT-CDs. The dissolution rate of KT was markedly increased by inclusion complex formation with CDs in the buffer solution at pH 4.0 and pH 6.8. The mean dissolution time (MDT,min), which represents the rapidity of dissolution, was in the order of $KT-DM{\beta}CD$ IC (3.20) < $KT-{\beta}-CD$ IC (4.36) < $KT-{\alpha}-CD$ IC (6.99) < $KT-{\alpha}-CD$ PM (17.46)< $KT-{\beta}-CD$ PM (19.36) < $KT-{\beta}-CD$ PM (28.53). The dissolution rates of KT-CD ICsprepared by solvent evaporation method were faster than those of KT-CD ICs prepared by freeze-drying method.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.126-130
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• 1995

$CdS_{1-x}Te_{1-x}$ polycrystalline thin films were fabricated from CdS and CdTe powder by co-evaporation method at $10^{-6}$ Torr. The Optimum evaporation condition was substrate temperature $T_{s}$=$150^{\circ}C$, evaporation time t=30 min. XRD spectrums indicated that the crystal structure chanced from zinc blonde (x$\leq$0.22) to wurtzite (x$\geq$0.96) through mixed structure (0.22$\leq$0.74) as composition value x increase to CdS. Conductive type was n-type by hot point probe method. van der Pauw method was not applicable for x<0,5 due to high hall voltages, Electrical resistivity and Hall carrier mobility were decreased as x increase, while Hall carrier concentration was increased. The optical bandgap of $CdS_{1-x}Te_{1-x}$ polycrystalline thin films measure d at R.T. had quardratic form and the bowing parameter was fitted as 1.98eV for theoretical value of 2.0eV. I-V characteristics of In/CdTe/$CdS_{x}Te_{1-x}$Au Schottky diodes showed that CdS-rich one had better forward characteristics than CdTe-rich one.

• 방사선산업학회지
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• 제8권1호
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• pp.17-22
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• 2014

In this study, we prepared CdTe/CdS solar cells using a thermal vacuum evaporation method. In particular, $CdCl_2$ treatment was attempted using this same method at $400^{\circ}C$ for 30 min. The prepared CdTe/CdS solar cells were investigated using Fouier transform infrared spectrometry (FTIR), field emission scanning electron microscopy (FE-SEM), and a solar simulator system including light absorption properties, morphological properties, and power conversion efficiency (PCE). In addition, we investigated the gamma-irradiation treatment at dose rates of 0 Gy, 500 Gy, 1 kGy, 10 kGy, and 30 kGy. The characteristics of gamma-irradiation treatment were studied based on the same method described above. In particular, it showed increased values as 0.826% higher than the non-irradiation of 0.448% from PCE analysis.

• 한국세라믹학회지
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• 제30권11호
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• pp.897-904
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• 1993

CdS doped SiO2 glass coating films which are good candidates for the nonlinear optical materials were prepared by the Sol-Gel method. TEOS, C2H5OH, H2O and HCl were used as starting materials to obtain SiO2 matrix solutions. Then Cd(NO3)2.2H2O and CS(NH2)2 were dissolved into the SiO2 matrix solutions. Coating was performed several times in order to increase the thickness of coated film by the dip-coating method. Then heat treatments were carried out to control the size of CdS microcrystals doped in SiO2 glass matrix with respect to temperatures and times. CdS-doped SiO2 transparent coating films were successfully obtained. CdS crystals were changed from cubic to hexagonal type about $600^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.180-181
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• 2006

CdSe single crystal was grown by sublimation method in the two-step vertical electric furnace. This CdSe single crustal had hexagonal structure whose lattice constants of $a_0$ and $c_0$ were measured $4.299\;{\AA}$ and $7.009\;{\AA}$ by extrapolation method, respectively. CdSe single crystal was n-type semiconductor values were measured from Hall data by Van der Pauw method in the room temperature. Mobility tends to increase in proportion to $T^{3/2}$ from 33K to 130K due to impurity scattering. but mobility tends to decrease in proprtion to $T^{-3/2}$ from 130K to 293K due to lattice scattering. CdSe thin film was made by electron beam evaporation technique had also hexagonal structure. The grain size of this thin film was grown to $1{\mu}m$ as a result of annealing in the vapor of Ar or Cd. Annealde CdSe thin film was n-type semiconductor whose carrier density had about $7{\times}10^{12}cm^{-3}$ and its mobility had about $1.6{\times}10^3cm^2/V$ sec at room temperature.

• 한국측량학회지
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• 제34권4호
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• pp.391-402
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• 2016

Among the various remote sensing sensors compared to the electro-optical sensors, SAR (Synthetic Aperture Radar) is very suitable for assessing damaged areas induced by disaster events owing to its all-weather day and night acquisition capability and sensitivity to geometric variables. The conventional CD (Change Detection) method that uses two-date data is typically used for mapping damage over extensive areas in a short time, but because data from only two dates are used, the information used in the conventional CD is limited. In this paper, we propose a novel CD method that is extended to use data consisting of two pre-disaster SAR data and one post-disaster SAR data. The proposed CD method detects changes by using a similarity weight image derived from the neighborhood information of a pixel in the data from the three dates. We conducted an experiment using three single polarization ALOS PALSAR (Advanced Land Observing Satellite/Phased Array Type L-Band) data collected over Miyagi, Japan which was seriously damaged by the 2011 east Japan tsunami. The results demonstrated that the mapping accuracy for damaged areas can be improved by about 26% with an increase of the g-mean compared to the conventional CD method. These improved results prove the performance of our proposed CD method and show that the proposed CD method is more suitable than the conventional CD method for detecting damaged areas induced by disaster.

• 전기학회논문지
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• 제60권6호
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• pp.1169-1174
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• 2011

CdTe thin-film solar cell technology is well known that it can theoretically improve its conversion efficiency and manufacturing costs compared to the conventional silicon solar cell technology, due to its optical band gap energy (about 1.45eV) for solar energy absorption, high light absorption capability and low cost requirements for producing solar cells. Although the prior studies obtained the high light absorption, CdTe thin film solar cell has not been come up to the sufficient efficiency yet. So, doping method was selected for the improvement of the electrical characteristics in CdTe solar cells. Some elements including Cu, Ag, Cd and Te were generally used for the p-dopant as substitutional acceptors in CdTe thin film. In this study, the sputtering-deposited CdTe thin film was immersed in $AgNO_3$ solution for ion exchange method to dope Ag ions. The effects of immersion temperature and Ag-concentration were investigated on the optical properties and electrical characteristics of CdTe thin film by using Auger electron spectroscopy depth-profile, UV-visible spectrophotometer, and a Hall effect measurement system. The best optical and electrical characteristics were sucessfully obtained by Ag doping at high temperature and concentration. The larger and more uniform diffusion of Ag ions made increase of the Ag ion density in CdTe thin film to decrease the series resistance as well as mede the faster diffusion of light by the metal ions to enhance the light absorption.