• JSTS:Journal of Semiconductor Technology and Science
• /
• v.15 no.2
• /
• pp.267-275
• /
• 2015

In this paper, ZnO films were prepared by atomic layer deposition (ALD) and CdS films were deposited using chemical bath deposition (CBD) to form ZnO/CdS heterojunction. More accurate mapping of band arrangement of the ZnO/CdS heterojunction has been performed by analyzing its electrical and optical characteristics in depth by various methods including transmittance, x-ray photoemission spectroscopy (XPS), and ultraviolet photoemission spectroscopy (UPS). The optical bandgap energies ($E_g$) of ZnO and CdS were 3.27 eV and 2.34 eV, respectively. UPS was capable of extracting the ionization potential energies (IPEs) of the materials, which turned out to be 8.69 eV and 7.30 eV, respectively. The electron affinity (EA) values of ZnO and CdS calculated from IPE and $E_g$ were 5.42 eV and 4.96 eV, respectively. Energy-band structures of the heterojunction could be accurately drawn from these parameters taking the conduction band offset (CBO) into account, which will substantially help acquisition of the full band structures of the thin films in the CIGS solar-cell device and contribute to the optimal device designs.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.18 no.1
• /
• pp.157-166
• /
• 2004

In order to understand the anti-carcinogenic effects of Boo-jung-bae-bon-bang(扶正培本方)-B1), Hwal-hyul-hwa-eo-bang(活血化瘀方-B2), Cheong-youl-hae-dok-bang(淸熱解毒方-B3), prescriptions of individual B1, B2, and B3 treatments or combined treatments (B4; B1+B2, B5; B1+B3, B6; B1+B2+83, B7; B2+83) were applied to cultured cancer cell lines. The major findings on their anti-cardnogenic effects in terms of mechanism and synergistic interactions are summarized below. Results of cytokine gene expression analyses are summarized as follows; IL-2 gene expression was increased by B1 and B6 treatments, IFN-v gene expression increased by B3, B1, B6, and 85, and CD28 gene expression increased by B1 and B5. IL-4 expression was not affected by any treatments. In the FACS analysis, increases in numbers of immunoreactive CD3/sup +//CD25/sup +/ T cells by B1 and B5 treatment, CD3/sup +//CD69/sup +/ T cells by B1, B3, B5, and B6 treatments, CD19/sup +//CD44/sup +/ B cells by B1 and B6 treatments were observed when compared to the corresponding non-treated control groups.

• Journal of Korean Society on Water Environment
• /
• v.36 no.6
• /
• pp.559-567
• /
• 2020

The abnomal responseses on growth and morphology of attached diatoms by various heavy metals were studied. Ulnaria ulna (Nitzsch) Compère was employed as experimental species and exposed to the five heavy metals such as Cu, Zn, Pb, Cd, and As with four concentrations (0, 0.01, 0.1, and 2 mg L-1), respectively. The samples of Ulnaria ulna were examined on the changes of cell growth and teratological forms on the 7th, 14th, 21th, and 28th day, respectively, after exposure to the heavy metals. The samples exposed to the highest concentration, 2.0 mg L-1, of all the heavy metals showed the most obvious decreases of growth. The samples exposed to Cd (μ=0.049day-1) and As (μ=0.048day-1) showed the highest decreasing rate of growth (p=0.021(Cd), p=0.002(As)) and the highest morphological changes of diatom valves were also samples exposed to Cd (10.41%) and As (10.13%) (p=0.009 (Cd), p=0.005(As)). In contrast, Pb induced the lowest decreasing rate (μ=0.090 day-1) and the least change in valve morphology (3.31%). The Cd and As showed relatively stronger effects on growth rates compared to Cu, Zn, and Pb. For the percentage of emergence of morphological species by the type, the highest percentage were observed in sampled exposed to type 1 (43.4%) and followed by type 2 (29.1%). The type 2 and 4 were most abundant in samples exposed to Zn and Pb while the type 3 was most abundant in Cd and As. The Cu induced only type 1, suggesting that the frequency of emergence of each type varied among hevay metals. This research suggests that the degrees of abnomal changes on growth rate and valve morphology of Ulnaria ulna can be used as a bioindicater species for heavy metal contamination in freshwater.

• Analytical Science and Technology
• /
• v.21 no.6
• /
• pp.562-568
• /
• 2008

A novel two-dimensional cadmium(II)-nickel(II) bimetallic host clathrate, $[Cd{NH_2CH_2CH_2OH}_2Ni(CN)_4]{\cdot}3C_6H_5NH_2{\cdot}H_2O$, 1, has been synthesized and structurally characterized by X-ray single crystallographic method. The clathrate 1 crystallizes in the monoclinic system, space group $P2_1/c$ with a = 14.370(3), b = 7.728(1), c = 28.172(4) ${\AA}$, ${\beta}=97.58(1)^{\circ}$, V = 3101.1(9) ${\AA}^3$, Z = 4. The host framework of the clathrate 1 is built of the cyanide bridges between octahedral Cd(II) atom and square planar Ni(II) atom. The octahedral Cd atoms ligated by two 2-aminoethanol molecules and four cyanide ligands bridged with square planar Ni atoms. The Ni atoms bridges to four Cd atoms via cyanides is made up of puckered quadrangles of composition $\{CdNi(CN)_2\}_2$, all edges are shared. This cyanide bridges form an infinite two-dimensional host networks stacking along b axis. 2-Aminoethanol ligands bond to Cd atom through N atom as a monodentate ligand in the axial position and four cyanides take an equatorial plane with all in trans-configurations. The aniline guest molecules and water molecules are located in between the host layer sheets, respectively.

• Korean Journal of Clinical Pharmacy
• /
• v.22 no.2
• /
• pp.95-102
• /
• 2012

HIV 치료를 위한 강력한 항바이러스 약물요법이 널리 사용됨에 따라 HIV에 감염된 상태에서 신장질환 발생 위험성을 지닌 채 오랜 기간 생존하는 환자들이 증가하고 있다. 본 연구는 국립중앙의료원 감염병 센터를 내원한 만18세 이상의 HIV 감염 환자를 대상으로 HIV 감염 환자에게 신기능 장애를 유발하는 위험인자를 평가하고자 환자군 대조군 연구를 후향적으로 실시하였다. 2006년 1월부터 2011년 3월까지 5년 3개월 동안 신기능이 저하된 모든 HIV 감염 환자를 환자군으로 하며, 정상 신기능을 가진 HIV 감염 환자들 중 대조군을 무작위로 선정하여 환자군과 대조군을 1:2의 비율로 하였다. 환자군과 대조군을 비교해 만성신질환을 유발하는 위험인자를 평가하기 위한 분석변수로 성별, 연령, CD4+ 세포수, 혈중 바이러스 수, HAART 56일 이상 여부, 당뇨병과 C형 간염을 선정하였다. 또한 추가적으로 개별 antiretroviral 약물들 사용과 신기능이 얼마나 관련되어 있는지 알아보기 위해 각각의 약물과 eGFR의 상관관계를 분석하였다. 환자군은 CD4+ 세포수가 < $200{\times}10^6$ cells/l 인 군이 7.7배(OR: 7.7; 95% CI, 1.8-32.9) 단백뇨가 있는 환자의 경우 7.8배(OR: 7.8; 95% CI, 1.6-37.8) 더 유의하게 만성신질환 발생위험이 높았다. 개별 antiretroviral 약물들과 eGFR의 상관관계를 분석한 결과, lamivudine 이 eGFR 과 약한 음적 상관관계를 보이는 것으로 나타났으며(r = -.211, p < .05), 다른 약물들의 경우 통계적으로 유의한 값을 보이지 않았다. 이번 환자군-대조군 연구는 HIV 감염 환자들이 만성 신질환으로 발전하는데 여러 인자들의 역할에 대해 평가하고자 하였다. 여러 변수들을 평가해 본 결과, 만성 신질환 환자들의 경우 CD4+ 세포수가 < $200{\times}10^6$ cells/l 이거나 단백뇨를 동반한 경우가 통계적으로 유의하게 많았다.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.3
• /
• pp.289-295
• /
• 2010

Monitoring of the heavy metals at paddy rice agriculture is very important for environmental agriculture. A study was carried out of heavy metal concentrations in 260 paddy soil samples every four years from 1999 to 2007 in Gyeongnam Province. Heavy metals such as Cd, Cr, Cu, Ni, Pb, Zn, and As in paddy soils were analyzed. Average concentrations of heavy metal were Cd 0.426 (ranged 0.003-1.379) mg $kg^{-1}$ for Cd, 1.189 (0.003-3.264) mg $kg^{-1}$, for Cr, 9.68 (0.05-22.38) mg $kg^{-1}$ for Cu, 2.64 (0.01-7.36) mg $kg^{-1}$ for Ni, 23.7 (0.7-54.1) mg $kg^{-1}$ for Pb, 20.8 (0.7-131.2) mg $kg^{-1}$ for Zn, and 1.054 (0.001-2.110) mg $kg^{-1}$ for As, respectively. Long-term changes of heavy metals were showed that Cd, Ni, and Zn were significantly increased whereas Cr, Cu, and As were significantly decreased. Principle component analysis (PCA) of heavy metals in paddy soils was obtained with eigenvalues > 1 summing 34.3% of variance for PC1, 17.5% of variance for PC2, and 51.8% of the total variance in soil heavy metals.

• The Journal of the Acoustical Society of Korea
• /
• v.36 no.6
• /
• pp.387-393
• /
• 2017

The dynamic interactions between benzoic acid derivative ($pH{\approx}7.0$)(guest) and ${\beta}$-cyclodextrin (${\beta}$-CD)(host) were investigated in an aqueous solutions in terms of ultrasonic absorption in the frequency range 0.2 MHz ~ 50 MHz with emphasis on the low-frequency range below 1 MHz at $25^{\circ}C$. We show that the interaction of ${\beta}$-CD and benzoic acid derivative complies with a typical spectrum of a single relaxation process around a few MHz. The ultrasonic relaxation observed in these solutions was due to a perturbation of a chemical equilibrium related to a reaction of an inclusion complex formed by the host and guest. The rate constant ($k_b=7.48{\times}10^6M^{-1}s^{-1}$) and equilibrium constant ($K=68.6M^{-1}$) were determined from the concentration dependences of benzoic acid on the relaxation frequency. The standard volume change (${\Delta}V=10.6{\times}10^{-6}m^3mol^{-1}$) of the reaction was also computed from the maximum absorption per wavelength. It was found that the hydrophobicity of guest molecules played an important role in the formation of the inclusion complex.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.154.2-154.2
• /
• 2016

In this work, we introduce a solution-processed CdS interlayer for use in inverted bulk heterojunction (BHJ) solar cells, and compare this material to a series of standard organic and inorganic cathode interlayers. Different combinations of solution-processed CdS, ZnO and conjugated polyelectrolyte (CPE) layers were compared as cathode interlayers on ITO substrates to construct inverted solar cells based on $PTB7:PC_{71}BM$ and a $P3HT:PC_{61}BM$ as photoactive layers. Introduction of a CdS interlayer significantly improved the power conversion efficiency (PCE) of inverted $PTB7:PC_{71}BM$ devices from 2.0% to 4.9%, however, this efficiency was still fairly low compared to benchmark ZnO or CPE interlayers due to a low open circuit voltage ($V_{OC}$), stemming from the deep conduction band energy of CdS. The $V_{OC}$ was greatly improved by introducing an interfacial dipole (CPE) layer on top of the CdS layer, yielding outstanding diode characteristics and a PCE of 6.8%. The best performing interlayer, however, was a single CPE layer alone, which yielded a $V_{OC}$ of 0.727 V, a FF of 63.2%, and a PCE of 7.89%. Using $P3HT:PC_{61}BM$ as an active layer, similar trends were observed. Solar cells without the cathode interlayer yielded a PCE of 0.46% with a poor $V_{OC}$ of 0.197 V and FF of 34.3%. In contrast, the use of hybrid ZnO/CPE layer as the cathode interlayer considerably improved the $V_{OC}$ of 0.599 V and FF of 53.3%, resulting the PCE of 2.99%. Our results indicate that the CdS layer yields excellent diode characteristics, however, performs slightly worse than benchmark ZnO and CPE layers in solar cell devices due to parasitic absorption below 550 nm. These results suggest that the hybrid inorganic/organic interlayer materials are promising candidates as cathode interlayers for high efficiency inverted solar cells through the modification of interface contacts.

• Parasites, Hosts and Diseases
• /
• v.31 no.3
• /
• pp.231-238
• /
• 1993

Effects of Paragonims westermai infection were observed in mice on the change of serum IgE level, the number of peripheral eosinophils and the distribution of Thy $1.2^{+}{\;}(CD3),{\;}L3T4^{+}{\;}(CD4),{\;}and{\;}Lyt-2^{+}$ (CD8) splenic T Iymphocytes without mitogen serum IgE increased at 3 weeks after the infection and reached a peak on week 4 and maintained high levels of IgE until the 23r6 week. Peripheral eosinophil numbers Increased at the second week and attained peak level on week 9. The frequency of $L3T4^{+}$(CD4) and $Lyt-2^{+}$ (CD8) T Iymphocytes decreased slightly until 4 weeks after the infection, but not significantly. Absolute number of $L3T4^{+}{\;}and{\;}Lyt-2^{+}$ T Iymphocytes, and the ratio of L3T4/Lyt-2 were not markedly changed over the period of observation. The frequency of Thy $1.2^{+}$ (CD3) T lymphocytes in the infected group slightly decreased until 4 weeks after the infection and showed significant reductions at the 2nd and 4th week of the infection (p < 0.05).

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.2
• /
• pp.125-130
• /
• 2001

Experimental culture of Halocynthia roretzi was carried out near coast by Wolsung from January to August 1997 to investigate accumulation of heavy metals (Cd, Pb and Cu) by H. roretzi, Water temperature, salinity, pH and Suspended Particulate Matter (SPM) were $10.7\sim25.2^{\circ}C$, $33.0\sim34.6\%_{\circ},\;8.25\sim8.49\;and\;3.84\ksim7.92\;mg/L$, respectively, The heavy metal accumulation in H. roretzi was in the order of Cu>Pb>Cd. Heavy metal concentrations in the organs showed following order; Gill${\geq}Viscera{\gg}$Gonad>Muscle>Mantle for Cd, $Gill{\geq}Viscera{\gg}$ Gonad> Muscle$ {\geq}$Mantle for Pb and Viscera>Gill${\gg}$ Gonad>Muscle>Mantle for Cu.