• Nano
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• v.13 no.10
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• pp.1850118.1-1850118.17
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• 2018

Nanoparticles of the semiconductor catalyst $Cd_xZn_{1-x}S$ were embedded into the metal organic framework MIL-101(Cr) to obtain $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites. These materials not only possess high surface areas and mesopores but also show good utilization of light energy. The ultraviolet-visible diffuse reflectance patterns of $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites showed that $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed good visible light response ability among the synthesized nanocomposites. The photocatalytic performance of the $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites were tested via degradation and mineralization of methylene blue in neutral water solution under light irradiation using a 300W xenon lamp. As a result, using $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) as a catalyst, 99.2% of methylene blue was mineralized within 30 min. Due to the synergistic effect of adsorption by the MIL-101(Cr) component and photocatalytic degradation provided by the $Cd_{0.8}Zn_{0.2}S$ component, the $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) catalyst displayed superior photocatalytic performance relative to $Cd_{0.8}Zn_{0.2}S$ and MIL-101(Cr). Furthermore, $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed excellent stability during photodegradation and exhibited good reusability. The remarkable photocatalytic performance of $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) is likely due to the effective transfer of electrons and holes at the heterojunction interfaces.

• Electrical & Electronic Materials
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• v.7 no.1
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• pp.49-56
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• 1994

Polycrystalline CdS thin films were deposited by using EBE method and its crystal structure, surface morphology, electrical and optical properties as a function of annealing temperature were investigated. It was found that optimum growth conditions were substrate temperature annealing temperature 300[.deg. C]. The films were hexagonal structure preferred(002) plane and maximum grain size was 421[.angs.]. As the results, resistivity and optical transmittance of CdS thin films were $8.3{\times}{10^3}$[.ohm.cm] and 89[%] respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.149-149
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• 2011

CdS films were deposited on glass substrates by R.F. magnetron sputtering method and the films were annealed at various substrate temperatures ranging from room temperature to $300^{\circ}C$. Structural properties of the films were studied by X-ray diffraction analysis. The structural parameters as crystallite size have been evaluated. The crystallite sizes were found to increase, and the X-ray diffraction patterns were seen to sharpen by increasing substrate temperatures. X-ray diffraction patterns of these films indicated that they contain both cubic (zincblende) and hexagonal (wurtzite) structures as a mixture. Optical properties of the films were measured at room temperature by using UV/VIS spectrometer in the wavelength range of 190 to 1100nm and optical absorption coefficients were calculated using these data. The energy gap of the films was found to decrease, and the band edge sharpness of the optical absorption was seen to oscillate by annealing. The results show that heat treatments under optimal annealing condition can provide significant improvements in the properties of CdS thin films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.9
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• pp.693-699
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• 1998

In this work $Cd_4GeS_6:Co^{2+}$(0.5mole%) single crystals were grown by the chemical transporting reactiov(CTR) method using high purity(6N) elements. The grown single crystals crystallized in a monoclinic structure(space group Cc). The direct optical energy gap of this single crystals was found to be 2.445eV at 300K and the temperature dependence of optical energy gap was fitted well to Varshni equation. But at temperatures lower than 70K an anomalous temperature dependence of the optical energy gap was obtained. This anomalous temperature dependence accored well with the anomalous temperature dependence of the unit cell volume. Also, the entropy, enthalpy and heat capacity were deduced from the temperature dependence of optical energy gaps.

• The Journal of Korean Medicine
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• v.24 no.3
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• pp.1-10
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• 2003

Background : Asthma is a chronic inflammatory disorder under immunological influence. Gamichunggumgangwha-tang (CG, Jiaweiqingjinjianghuo-tang) and Gamiyukmigiwhang-tang (YM, Jiaweiliuweidihuang-tang) are herbal tonics for asthma from traditional herbal medicine. Objective : To evaluate the effect of CG and YM on immune cell & serum OA-specific IgE in broncho-alveolar lavage fluid (BALF) in a rat asthma model. Materials and Methods : Rats were sensitized with OA; at day I sensitized group and CG and YM groups were systemically immunized by subcutaneous injection of 1mg OA and 300mg of Al(OH)3 in a total volume of 2ml. At the same time, 1 ml of 0.9% saline containing $6{\times}10^9$ B. pertussis bacilli was injected by Lp. 14 days after the systemic immunization, rats received local immunization by inhaling 0.9% saline aerosol containing 2% (wt/vol) OA. A day after local immunization, BALF was collected from the rats. Rats were orally administered with each of CG and YM extract for 14 days since the day after local immunization. Lymphocyte, CD4＋ T cell and CD8＋ T cell counts, CD4＋/CD8＋ ratio in BALF, change of serum OA-specific IgE level, CD4＋ T cell and CD8＋ T cell percentages in the peripheral blood were measured and evaluated. Results : CG and YM showed an alleviating effect on asthmatic responses of rats. CG decreased total cell, lymphocyte, CD4＋ T cells in BALF, and serum OA-specific IgE level as compared with the control group. YM decreased lymphocytes as compared with the control group. CD4＋/CD8＋ ratio in BALF from the CG and YM groups and serum OA-specific IgE level from the YM group didn't show any significant variation from the control group. Conclusion : CG alleviated asthmatic hyperreactivity of the immune system through CD4＋ T cells and serum IgE. Further the study of this immune system modulating mechanism is expected.

• Journal of Pharmaceutical Investigation
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• v.31 no.3
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• pp.151-160
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• 2001

The purpose of this study is to investigate the interaction of progesterone with various cyclodextrins (CDs) in the aqueous solution and in solid state, and finally to formulate a parenteral aqueous formulation. CDs used were ${\alpha}-$, ${\beta}-$, and ${\gamma}-CD$, $2-hydroxypropyl-{\beta}-CD$ (HPCD), sulfobutyl $ether-{\beta}-CD$ (SBCD), $dimethyl-{\beta}-CD$ (DMCD) and $trimethyl-{\beta}-CD$ (TMCD). The solubility studies of progesterone were performed in the presence of various CDs as a function of concentration or temperature. The solubility of progesterone increased in the rank order of ${\alpha}-CD$ < ${\beta}-CD$ < ${\gamma}-CD$ < TMCD$ < HPCD < DMCD < SBCD. Addition of SBCD (200 mg/ml) in water increased the aqueous solubility $(9.36\;{\mu}g/ml)$ about 3,200 times, and lowering the temperature facilitated the solubilization of progesterone. However, the addition of HPCD and SBCD in 20:80 (v/v) polyethylene glycol 300-water and propylene glycol-water cosolvents markedly decreased the solubility of progesterone, compared with solubilizing effects in water. Physical mixtures and solid dispersions of progesterone with HPCD or SBCD were prepared, and evaluated by differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), near IR spectroscopy and dissolution studies. By DSC and IR studies, it was found that progesterone was dispersed in HPCD in monotectic state and dissolved rapidly from both solid dispersions. Based on solubility studies, new aqueous progesterone fonnulations (5 mg/ml) containing SBCD (200 mg/ml) could be prepared and did not form precipitates even after 2 months at $4^{\circ}C$. The solution was transparent when mixed with normal saline and 5% dextrose injection at 1: 1, 1:10 and 1:20 (v/v) even after 7 days. Permeation rates of progesterone through a cellulose membrane from 20% PEG 300 solution $(50\;{\mu}g/ml)$ containing HPCD or SBCD were compared with oily formulation. Permeation of progesterone from oily formulation did not occur up to 8 hr, but aqueous formulations showed fast permeation rates from early stage of permeation study. The addition of HPCD or SBCD retarded the permeation rates of progesterone with the increase of CD concentrations, suggesting the possibility of a controlled absorption from the site administered intramuscularly. These results demonstrate that it is feasible to develop a new progesterone parenteral aqueous injection (5 mg/ml) using SBCD.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.113-113
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• 1998

C CdTe와 HgCdTe는 광전소자나 태양전지,x 선 및 y 선 감지 소자 그리고 적외선 감지소 자로의 웅용둥으로 인하여 많은 연구가 진행되고 있다. 광전소자를 제작함에 있어서 깊은 준위나 얄은 준위에 있는 몇들은 운반자 수명에 매우 큰 영향을 미치고 있음에도 불구하고 광전도도 측정에 의한 운반자 수명 연구에 대하여는 보고된 것이 별로 없다. 이에 본 논문에서는 CdTe 시료의 광전도도를 측정하여 운반자 수명 및 깊은 준위의 위치를 알아보았다 M MBE방법을 이용하여 CdTe 기판위에 In을 도핑한 CdTe를 성장하였다. 광전도 붕괴(PCD) 측정은 300 K에서부터 400 K까지 온도를 변화시켜주면서 측정을 하였고 광원으로서 G GaP- LED를 사용하였으며 전압 신호를 읽기 위하여 Tektronix 2430A 오실로스코프를 이용하 였다 .. Fig. 1. 에서 보인바와 같이 광전도 붕괴곡선은 접선으로 나타낸 하나의 지수 함수적 붕 괴(a2exp( -t/ r 2))보다는 설선으로 나타낸 두 개의 지수함수적 붕괴(alexp( νr 1)+a2exp( -νr 2)) 가 더욱 잘 실험결과와 일치함을 알 수 있었다. 이러한 것은 과잉 전하에 대한 깊은준위를 가 지고 있는 반도체물질에서 일반적으로 관찰되는 것으로 시료가 n 형이기 때문에 소수 운반자 인 정공의 벚에 의한 것으로 생각된다 .. Fig. 2. 에서는 운반자 수명의 온도에 대한 변화를 나타 낸 것이다. 온도가 증가함에 따라 운반자 수명이 감소하는 경항올 보이고 있으며 이것올 이용 하여 딪익 활성화 에너지를 계산 하여 본 결과 0.35 eV 와 0.43 eV염을 알수 있었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.338-338
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• 2007

Photo-conductive properties of CdS films deposited on glass substrates by a reactive sputtering in Ar atmosphere were characterized as a function of working pressure and the film thickness. The XRD measurements of CdS films revealed obvious (002) preferred orientation. In 300nm-thick of films, difference between dark and photo-resistance increases with increasing working pressure within the films. The films at 5 mTorr of working pressure show a dark resistance of approximately $1\;{\times}\;10^6\;{\Omega}/{\square}$ and a photo-resistance of $3\;{\times}\;10^4\;{\Omega}/{\square}$. The decrease dark- and photo-resistance of films as thickness decrease were $1.4\;{\times}\;10^6$ and $3\;{\times}\;10^4\;{\Omega}/{\square}$, respectively. CdS films deposited on glass substrates are considered tobe suitable for photo-conductivity materials in stealth radome applications.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.432-432
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• 2013

현대에 이르러 직접방식 엑스선 검출기에서는 기존의 a-Se을 주로 이용하였지만, 고전압 인가에 따른 회로 손상과 짧은 수명, 그리고 누설전류에 따른 안전의 문제 등으로 낮은 에너지 밴드갭과 높은 흡수효율, 비저항 등에 의거한 다양한 대체 물질에 대한 연구가 활발하게 이루어져가고 있다. 본 논문에서는 직접방식 엑스선 검출물질로 전기이동도와 흡수효율이 뛰어나고, 밴드갭이 낮아 태양전지분야 뿐만 아니라 최근 엑스선 검출물질로 각광받고 있는 CdTe를 선정하였다. 연구의 목적은 PVD (Physical Vapor Deposition)방식의 CdTe 검출 물질의 제작과정에서 CdTe가 기화되어 하부전극 기판에 증착될 시, 하부전극 기판 온도에 따른 CdTe의 박막형성과 전기적 측정을 실시하여 그에 따른 최적의 증착조건을 선정하는 것이다. 하부전극 기판으로는 Au/glass를 사용하였으며 증착 시, $200^{\circ}C$, $300^{\circ}C$, $400^{\circ}C$로 나누어 특성을 평가하였다. 시료는 파우더형태의 다결정CdTe를 120 g를 사용하여 증착완료 시, 약 $100{\mu}m$의 박막두께를 구현하였다. PVD증착의 조건으로는 Mo재질의 보트를 사용하였으며, 증착 시 진공도는 $5{\times}10^{-6}$ Torr, 보트온도는 약 $350^{\circ}C$ 소요시간은 5시간이었다. 증착이 완료된 CdTe의 표면구조와 전기적 특성평가를 위해 SEM촬영을 실시하였고, 전기적 특성 평가를 위해 CdTe표면에 Au를 PVD방식으로 증착하였다. 실험 결과 SEM촬영을 이용한 표면특성에서는 하부전극 기판의 온도가 높아질수록 표면 결정입자가 증가하는 것을 확인할 수 있었으며, 전기적 특성에서도 하부전극 기판의 온도가 증가할수록 RQA-5 조건의 70 kVp, 100 mA, 0.03 sec 엑스선에 대한 우수한 민감도와 암전류 값을 확인하였다. 이러한 결과는 증착과정에서 온도에 따른 다결정 CdTe의 표면결정 크기 증가는 동일한 면적에서 표면결정 수의 감소를 뜻한다. 이는 결정간의 경계에서 트랩 되어지는 전자가 감소하고, 전자의 이동도 또한 높은 효율을 나타냄을 확인할 수 있었다. 따라서 본 연구를 통하여 CdTe기반의 직접방식 엑스선 검출기 제작과정에서 증착 시 하부전극기판 온도가 증가할수록 결정의 크기가 증가하여 최적의 전기적 특성을 나타냄을 검증할 수 있었다.

• IMMUNE NETWORK
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• v.14 no.6
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• pp.289-295
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• 2014

Flow cytometric immunophenotyping of peripheral blood lymphocyte subsets is a powerful tool for evaluating cellular immunity and monitoring immune-mediated diseases. The numbers and proportions of blood lymphocyte subsets are influenced by factors such as gender, age, ethnicity, and lifestyle. This study aimed to establish reference ranges for peripheral blood lymphocyte subsets in a healthy Korean population. Blood samples from 294 healthy adults were collected. Lymphocyte subsets were analyzed using a single-platform method with a flow cytometer; white blood cells and lymphocytes were analyzed using an automated hematology analyzer. The mean value of the white blood cell count was $5,665cells/{\mu}l$, and the mean values of the subtype counts (percentages) were as follows: lymphocytes, $1,928cells/{\mu}l$ (35.08%); $CD3^+$ cells, $1,305cells/{\mu}l$ (67.53%); $CD3^+CD4^+$ cells, $787cells/{\mu}l$ (40.55%); $CD3^+CD8^+$ cells, $479cells/{\mu}l$ (25.23%); $CD3^-CD19^+$ cells, $203cells/{\mu}l$ (10.43%); and $CD3^-CD56^+$ cells, $300cells/{\mu}l$ (15.63%). Additionally, the $CD4^+/CD8^+$ ratio was 1.81. In this study, gender and age significantly influenced blood lymphocyte subsets. Our results demonstrate that, as with other populations, a healthy Korean population has its own, region-specific, lymphocyte subset reference ranges.