• Title/Summary/Keyword: CD size

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Properties of CdS Thin Films Prepared by Chemical Bath Deposition as a Function of Thiourea/CdAc2 Ratio in Solution (CBD법으로 제작된 CdS 박막의 thiourea/CdAc2 농도비에 따른 특성)

  • Song, Woo-Chang
    • Journal of Surface Science and Engineering
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    • v.41 no.1
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    • pp.28-32
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    • 2008
  • In this paper CdS thin films, which were widely used window layer of the CdS/CdTe and the CdS/$CuInSe_2$ heterojunction solar cell, were grown by chemical bath deposition, which is a very attractive method for low-cost and large-area solar cells, and the structural, optical and electrical properties of the films was studied. As the thiourea/$CdAc_2$ mole ratio was increased, the deposition rate of CdS films prepared by CBD was increased due to increasing reaction velocity in solution and the optical bandgap was increased at higher thiourea/$CdAc_2$ mole ratio due to larger grain size and continuous microstructure. The minimum resistivity of the films was at thiourea/$CdAc_2$ mole ratio of 3.

Effect of Some Tea on Removability of Cd and Pb Ion in Solution (찻물에서의 Cd과 Pb이온 제거에 관한 차입자의 효과)

  • 김중만;백승화;박성수
    • The Korean Journal of Food And Nutrition
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    • v.11 no.5
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    • pp.521-527
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    • 1998
  • Removabilities of heavy metals(Cd and Pb) by the tea materials (barley-tea, corn-tea, jasmin-tea, brown rice-green tea, black-tea, cassia tora-tea, persimmon peel-tea, and rice-tea) in the tea-water were studied in the various conditions ; particle size of tea (20, 40, 70 mesh), concentration of heavy metal (25, 50, 100 ppm) and extraction temperature(20, 30, 50, 100$^{\circ}C$). The removabilities by the tea solids were increased as the particle size decreased, concentration of heavy metal increased, and extracting temperature increased. Of the nine kinds of tea, Cd and Pb removability by jasmin-tea was highest. In addition, heavy metal removability by cassia tora tea was better than that of other tea as extraction temperature was increased.

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Luminescent Characteristics of CdSe Quantum Dot Phosphor Depending on Se Precursor Ratio (Se 전구체 함량 따른 CdSe 양자점 형광체의 발광특성)

  • Eom, Nu Si A;Kim, Taek-Soo;Choa, Yong-Ho;Kim, Bum Sung
    • Journal of Powder Materials
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    • v.19 no.6
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    • pp.442-445
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    • 2012
  • The quantum dots (QD) have unique electrical and optical properties due to quantum dot confinement effect. The optical properties of QDs are decided by various synthesis conditions. In a prior QDs study, a study on the QDs size with synthesis condition such as synthesis time and temperature is being extensively researched. However, the research on QDs size with composition ratio has hitherto received scant attention. In order to evaluate the ratio dependence of CdSe crystal, synthesis ratio of Se precursor is changed from 16.7 mol%Se to 44 mol%Se. As the increasing Se ratio, the band gap was increased. This is caused by red shift of emission. We confirmed optical property of CdSe QDs with composition ratio.

Synthesis and analysis CdSe Quantum dot with a Microfluidic Reactor Using a Combinatorial Synthesis System (조합 합성 시스템의 미세유체반응기를 이용한 CdSe 양자점 합성 및 분석)

  • Hong, Myung Hwan;Lee, Duk-Hee;Kang, Lee-Seung;Lee, Chan Gi;Kim, Bum-Sung;Kim, Nam-Hoon
    • Journal of Powder Materials
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    • v.23 no.2
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    • pp.143-148
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    • 2016
  • A microfluidic reactor with computer-controlled programmable isocratic pumps and online detectors is employed as a combinatorial synthesis system to synthesize and analyze materials for fabricating CdSe quantum dots for various applications. Four reaction condition parameters, namely, the reaction temperature, reaction time, Cd/Se compositional ratio, and precursor concentration, are combined in synthesis condition sets, and the size of the synthesized CdSe quantum dots is determined for each condition. The average time corresponding to each reaction condition for obtaining the ultraviolet-visible absorbance and photoluminescence spectra is approximately 10 min. Using the data from the combinatorial synthesis system, the effects of the reaction conditions on the synthesized CdSe quantum dots are determined. Further, the data is used to determine the relationships between the reaction conditions and the CdSe particle size. This method should aid in determining and selecting the optimal conditions for synthesizing nanoparticles for diverse applications.

Characterization of CdS Thin Films and CdS/CdTe Heterojunction Prepared by Different Techniques (CdS 박막의 제조 방법에 따른 물성 및 CdS/CdTe 이종접합의 전기적 특성 분석)

  • Lee, Jae-Hyeong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.3
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    • pp.199-205
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    • 2005
  • Polycrystalline cadmium sulfide(CdS) thin films were deposited on glass substrate by chemical bath deposition(CBD) and vacuum evaporation (VE) techniques. VE-CdS films consisted primarily of hexagonal phase, whereas CBD CdS films containing primarily the cubic form. VE-grown films were shown to have better crystallinity than CBD-grown films. The grain size of the CBD films is smaller than the ones of VE films. VE-CdS films exhibited relatively high transmittance in the above-gap region and band gap compared with CBD films. However, CdTe solar cells with these low quality CBD-CdS layers yield higher and more stable characteristics. Current-voltage-temperature measurements showed that the current transport for both cells was controlled by both tunneling and interface recombination but the cells with CBD-CdS displayed less tunneling.

Effects of Herbal-acupuncture with Coicis Semen Solution at Joksamni (ST36) on Collagen-induced Arthritis in DBA/1J Mouse (족삼리(足三里) 의이인약침(薏苡仁藥鍼)이 Collagen으로 유발(誘發)된 생쥐의 관절염(關節炎)에 미치는 영향(影響))

  • Lee, Seong-No;Lee, Hyun
    • Korean Journal of Acupuncture
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    • v.24 no.4
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    • pp.111-129
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    • 2007
  • Objectives & Methods : The purpose of this study is to observe the effects of Coicis Semen Herbal-acupuncture solution (CS-HAS) at the Joksamni (ST36) on the collagen-induced arthritis in the DBA/1J mouse. The author performed several experiments to analyze the effects of CS-HAS on arthritis; change of the weight; the spleen size and adhesion rate; serum cytokine levels; serum antibody levels; changes of immunocyte counts; the histological changes of joint. Results : In the Coicis Semen Herbal-acupuncture (CS-HA), arthritis index, the incidence of arthritis, and the degree of joint edema were decreased. In CS-HA, there was no weight loss. The size of the spleen, adhesion rate, and the edema and transformation of joint were lowered. In CS-HA, the levels of IL-1${\beta}$, IL-6, TNF-${\alpha}$, IFN-${\gamma}$, IgG, IgM, and anti-collagen II in serum and the levels of IFN-${\gamma}$, IL-4, IL-10 in spleen were significantly decreased. In CS-HA, the expression ratios of $CD45^+$ to $CD3e^+$ and $CD8^+$ to $CD4^+$ were decreased. Also, the overall $CD4^+/CD8^+$ cell ratio was lowered in spleen. Ratios of the $CD4^+/CD25^+$, $CD45^+/CD69^+$ cells were decreased in lymph nodes. In addition, ratios of the $CD3^+/CD69^+$, $CD11b^+/Gr-1^+$ cells were also decreased in synovium. In the histological study, the cartilage destruction and synovial cell proliferation, and collagen fiber destruction were decreased with CS-HA treated group. Conclusions : From the results mentioned above, it is suggested that CS-HA at the ST36 has several significant effects on the collagen-induced arthritis.

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Morphological classification of Renal Disease Using $^{99m}Tc-DMSA$ Scintigram ($^{99m}Tc-DMSA$ 신티그램을 이용한 신질환 형태 분류)

  • Moon, Tae-Yong
    • The Korean Journal of Nuclear Medicine
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    • v.25 no.2
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    • pp.237-244
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    • 1991
  • $^{99m}Tc-DMSA$ renal scan has been evaluated not only the renal functional cell mass but also some anatomical structures at a loss of the renal parenchymal function. The author classified a renal morphology of the posterior image of $^{99m}Tc-DMSA$ renal scan as the groups of symmetric and asymmetric morphology, the groups of the large, normal and small sized kidneys, the groups of the central photon defects (PD) which could be noted in a dilated pelvocalyceal system due to obstructive uropathy and the cortical photon defects (CD) due to focal parenchymal lesions or scars after a loss of function and the last groups of the single and multiple CD for a suggestion of the clinical usefulness. Regarding to measurement of normal renal size, the longest size of the kidneys were evaluated with 5 cm of a lead scale on the posterior renal image, and those were decided to the limits beteen 104.1 and 119.4 mm as comparison with the renal size of intravenous pyelogram (IVP) in 59 cases who were underwent $^{99m}Tc-DMSA$ and IVP concommitantly. Among 85 cases of PD in $^{99m}Tc-DMSA$ renal scan, the 61 (71.8%) were cases of a dilated pelvocalyceal system related with obstructive uropathy, meanwhile the 28 (27.0%) of 162 cases with CD were cases of obstructive and infectious uropathy. The probability of a presence of some uropathy in cases of CD were 99.3%, meanwhile that of the presence of CD in cases of some uropathy were 37.9%. Besides, there were some specific anatomical findings such as polycystic kidneys with symmetric enlarged kidneys with multiple CD and the kidneys of chronic renal failure and/or hypertension with symmetric small size in $^{99m}Tc-DMSA$ renal stan.

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Copper Sulfide Nanowires for Solar Cells (태양전지용 $Cu_2S$ 나노와이어의 제작 및 특성분석)

  • Lim, Young-Seok;Kang, Yoon-Mook;Kim, Won-Mok;Kim, Dong-Hwan
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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    • pp.166-169
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    • 2006
  • We fabricated hexagonal copper sulfide $Cu_2S$ nanowires to obtain a larger contact area of $Cu_2S/CdS$ solar cell. Copper sulfide nanowires were grown on Cu foil at room temperature by gas-sol id reaction. The size, density and shape of nanowires seemed to be affected by the change or reaction time temperature, crystallographic orientation of Cu foil, and molar ratio of the mixed gas. We controled the length and the diameter of the nanowires and we obtained suitable nanowire arrays which has fitting size for uniform deposition with n-type CdS. CdS layer was deposited on the nanowire array by electrodeposition and it seemed to be uniform. The $Cu_2S/CdS$ nanowires/CdS junction showed diode characteristics, A large contact area is expected with the $Cu_2S/CdS$ nanowire structure as compared with the $Cu_2S/CdS$ thin film.

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Characterization of the CD11c Promoter Which Is Expressed in the Mouse Dendritic Cells (생쥐 수지상세포에서 발현하는 CD11c 프로모터의 규명)

  • Kim, Bon-Gi;Kim, Jung-Sik;Park, Chung-Gyu
    • IMMUNE NETWORK
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    • v.8 no.4
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    • pp.137-142
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    • 2008
  • Background: CD11c, also known as integrin alpha x, is one of the optimum markers of dendritic cells. However, the regulation of the CD11c expression in mouse has not been identified yet. In this study, in order to analyze the regulation of CD11c expression, the promoter of CD11c was cloned and characterized. Methods: To identify the promoter portion, various sizes of what are considered to be CD11c promoter fragments was amplified by polymerase chain reaction (PCR), using mouse genomic DNA as a template. After sequence was obtained, these fragments were transfected into various cell lines including mouse dendritic cell lines such as JAWSII and DC2.4 and L929 as control cell line.. The promoter activity of three promoter fragments was measured and compared by luciferase activity in the transfected cells. Results: Three clones with size of 1kb, 3kb and 6kb were obtained from mouse genomic DNA. Flow cytometry analysis of JAWSII cells revealed that 52% of the cells expressed CD11c, which was confirmed by RT-PCR analysis. On the contrary, L929 and DC 2.4 cells did not express CD11c. The CD11c+ JAWSII cells were enriched from 52% to 90% with cell sorter. The comparative luciferase activity analyisis demonstrated that the region responsible for tissue specific expression was contained within -3 kb and the clone with size of 3 kb particularly showed higher luciferase activity than 6 kb and 1 kb clones. Conclusion: The CD11c promoter region containing the region responsible for tissue specificity was successfully cloned and -3 kb region showed the highest activity.

Effect of bark on the adsorption of heavy metal ions (2) - Effect of Pinus densiflora and Quercus mongolica barks on the adsorption of Cu and Cd ions - (수피(樹皮)에 의(衣)한 중금속(重金屬) 흡착효과(吸着效果)(2) - 소나무와 신갈나무 수피(樹皮)에 의한 Cu와 Cd의 흡착효과(吸着效果) -)

  • Paik, Ki-Hyon;Kim, Kyung-Jik
    • Journal of the Korean Wood Science and Technology
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    • v.14 no.4
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    • pp.1-7
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    • 1986
  • This investigation involves a study of the physical and chemical factors of Pinus densiflora SIEB. et ZUCC. and Quercus mongolica Fisher barks affecting on the adsorption of heavy mteal ions. The results obtained can be summarized as follows. 1. The capacity of the untreated bark to remove the Cu and Cd from solution was similar to or 5% higher than that of formaldehyde treated bark in both species. Considering that untreated bark lead to color-leaching problem, bark treated with formaldehyde are economical. 2. With decreasing particle size of bark(20-80), the adsorption ratio of the Cu and Cd from solution was increased. Quercus bark adsorbed more Cu and Cd at smaller particle size compared to Pinus bark. 3. The heavy metal eqilibrium adsorption of the bark from Cu and Cd solution was attained within 10 min. Pinus bark removed about 48% of the Cu and 41% of the Cd from solution in 10 min while Quercus bark removed about 50% during that period. 4. As the initial metal concentration increased. the absolute metal uptake was increased while percentage removal was decreased. At the lower metal concentration (10 ppm). Pinus and Quercus barks removed 77-94% of the Cu and 72-84% of the Cd. At high metal concentration (200 ppm), the adsorption ratio was 40% Cu and 25% Cd, respectivelty. 5. The maximum adsorption of the Cu and Cd from solution was obtained at pH 5-6 in filtrate. 6. With increased bark weight per given metal concentration, absolute removal of metal ion from solution was increased, but the percentage removal was decreased. The amount of adsorption was 4.2 mg Cu and 4.2 mg Cd per gr. Pinus, bark and 5.4 mg Cu and 4.3 mg Cd per gr. Quercus bark, respectively.

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