• Title/Summary/Keyword: halide

Search Result 444, Processing Time 0.026 seconds

Effect of Supplemental Lighting of Sub-Compensation Intensities on Growth of Rosa hybrida L. 'Vital' (광보상점 이하의 보광이 절화장미 'Vital'의 생육에 미치는 영향)

  • Choi, Young-Hah;Kwon, Joon-Kook;Choi, Gyeong-Lee;Kang, Nam-Jun;Chun, Hee;Cho, Myeong-Whan;Seo, Tae-Cheol;Roh, Mi-Young;Lee, Seong-Chun;Lee, Jae-Han
    • Journal of Bio-Environment Control
    • /
    • v.17 no.2
    • /
    • pp.132-137
    • /
    • 2008
  • This experiment was conducted to investigate the effect of supplemental lighting of low light intensities on growth and yield of rose 'Vital' in a forcing culture. Metal halide lamp (MH), High pressure sodium lamp (HSP), and MH+HSP were used as the light sources, and they were set up at a $310\;cm{\times}450\;cm$ interval and at 120cm above the culture beds. Light intensity at 1m point distance from supplemental lighting sources was $32{\sim}34\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Days to the 1st and 2nd harvests decreased by $5{\sim}8$ and $3{\sim}5$days, respectively in supplemental lighting treatment as compared to the control. Days to harvesting was the shortest in MH+HPS treatment, followed by BPS and MH, although there was no significant difference between HPS and MH treatments. The growth was better and incidence of blind shooting decreased by $5{\sim}7%$ in supplemental lighting treatments than the control, increasing marketable cut flowers. The incidence of blind shoot was the lowest in MH+BPS treatment, and there were no significant difference between MH and BPS treatments. In conclusion, supplemental lighting of low light intensities was effective in reducing days to flowering and reduced occurrence of blind shoots.

A Study on the Kinetics of Copper Ions Reduction and Deposition Morphology with the Rotating Disk Electrode (RDE를 이용한 구리이온의 환원속도 및 전착형태에 관한 고찰)

  • Nam, Sang Cheol;Um, Sung Hyun;Lee, Choong Young;Tak, Yongsug;Nam, Chong Woo
    • Applied Chemistry for Engineering
    • /
    • v.8 no.4
    • /
    • pp.645-652
    • /
    • 1997
  • Electrochemical characteristics and kinetic parameters of copper ion reduction were investigated with a platinum rotating disk electrode (RDE) in a diffusion controlled region. Reduction of Cu(II) in sulfate had one-step two-xelectron process, while the reduction of Cu(II) in chloride solution was involved two one-electron processes. The transfer coefficient of Cu(II) in sulfate solution was lowest, and the transfer coefficient of Cu(I) in halide solutions had the value of nearly one. In chloride solutions, electrodeposition rate of Cu(II) was about one hundred times faster than Cu(I). Diffusion coefficient increased in the order of Cu(II) in chloride solution, Cu(I) in the iodide, bromide, chloride solution, Cu(II) in sulfate solution. The calculated ionic radii and activation energy for diffusion decreased in the same order as above. Morphological study on the copper electrodeposition indicated that the electrode surface became rougher as both concentration and reduction potential increases, and the roughness of the surface was analyzed with UV/VIS spectrophotometer.

  • PDF

Delayed Luminescence Characteristics of Human Hands (사람 손의 지연발광 특성)

  • Yang, Joon-Mo;Choi, Chun-Ho;Soh, Kwang-Sup;Lim, Woo-Taek;Lee, Han-Sang;Chae, Seung-Byung;Yoon, Se-Yeol;Lee, Kyung-Il;Shin, Eun-Seok;Choi, Sun-Mi
    • Korean Journal of Optics and Photonics
    • /
    • v.17 no.1
    • /
    • pp.81-88
    • /
    • 2006
  • Delayed luminescence from human hands after illumination by light at different wavelength bands was studied. A delayed luminescence measurement system equipped with photomultiplier tube (PMT), fiber optics and automatic mechanical shutter system was developed. Three spectrum band-pass filters, fer which transmissions are on 350${\~}$450 nm, 450${\~}$550 nm and 550${\~}$650 nm, were used to select irradiation wavelength, and 150W metal-halide lamp was used as an illumination source. Six volunteers put their palms (dorsa) onto the measurement system, and after light illumination, delayed luminescence were measured for 10 minutes. The results show that delayed luminescence after shorter wavelength illumination was higher than that a(ter longer wavelength one. These results indicate the existence of accepters in human skin which can be excited at short wavelengths. Furthermore, each subjects showed different delayed luminescence curve patterns. Reactive oxygen species (ROS) are known to have important roles on delayed luminescence, and this research suggests that ROS concentration can be measured noninvasively with optical methods.

Fibulin-3 as a Diagnostic Biomarker in Patients with Malignant Mesothelioma

  • Kaya, Halide;Demir, Melike;Taylan, Mahsuk;Sezgi, Cengizhan;Tanrikulu, Abdullah Cetin;Yilmaz, Sureyya;Bayram, Mehmet;Kaplan, Ibrahim;Senyigit, Abdurrahman
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.4
    • /
    • pp.1403-1407
    • /
    • 2015
  • Background: New tumour biomarkers are being intensely investigated for malignant mesothelioma (MM). Fibulin-3 is produced in MM but its role remains uncertain. The aim of this study was to evaluate the validity of measuring serum fibulin-3 in the diagnosis and prognosis of MM. Materials and Methods: This prospective study was performed on 43 patients and 40 healthy controls who were admitted to our hospital between January 2012 and January 2014. Data from MM patients, including demographic and clinical features, routine laboratory data, levels of serum fibulin-3, and treatment outcomes were defined as potential prognostic factors. The receiver operating characteristic (ROC) curve for fibulin-3 was used to detect the cut-off value with highest sensitivity and specificity. Univariate survival analysis was performed using the Kaplan-Meier method in patients with MM. Afterwards, the possible factors identified with univariate analyses were entered into the cox regression analysis. Results: Our results revealed that patients with MM had significantly higher serum levels of fibulin-3 than controls. The results showed that the best cut-off point was 36.6 ng/ml with an AUC (area under the curve)=0.976, sensitivity=93.0% and specificity=90.0. In our study, the initial significant poor prognostic factors were advanced stage, high white blood cell count, high platelet count, high C-reactive protein (p<0.05 for each variable). Later, according to multivariate analysis the results showed only advanced stage as significant parameter (p=0.040). Conclusions: We determined that real use for serum fibulin-3 was not for prognosis but for diagnosis in MM. Also advanced stage was associated with poor MM prognosis.

New Ruthenium Complexes for Semiconductor Device Using Atomic Layer Deposition

  • Jung, Eun Ae;Han, Jeong Hwan;Park, Bo Keun;Jeon, Dong Ju;Kim, Chang Gyoun;Chung, Taek-Mo
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.363-363
    • /
    • 2014
  • Ruthenium (Ru) has attractive material properties due to its promising characteristics such as a low resistivity ($7.1{\mu}{\Omega}{\cdot}cm$ in the bulk), a high work function of 4.7 eV, and feasibility for the dry etch process. These properties make Ru films appropriate for various applications in the state-of-art semiconductor device technologies. Thus, it has been widely investigated as an electrode for capacitor in the dynamic random access memory (DRAM), a metal gate for metal-oxide semiconductor field effect transistor (MOSFET), and a seed layer for Cu metallization. Due to the continuous shrinkage of microelectronic devices, better deposition processes for Ru thin films are critically required with excellent step coverages in high aspect ratio (AR) structures. In these respects, atomic layer deposition (ALD) is a viable solution for preparing Ru thin films because it enables atomic-scale control of the film thickness with excellent conformality. A recent investigation reported that the nucleation of ALD-Ru film was enhanced considerably by using a zero-valent metallorganic precursor, compared to the utilization of precursors with higher metal valences. In this study, we will present our research results on the synthesis and characterization of novel ruthenium complexes. The ruthenium compounds were easy synthesized by the reaction of ruthenium halide with appropriate organic ligands in protic solvent, and characterized by NMR, elemental analysis and thermogravimetric analysis. The molecular structures of the complexes were studied by single crystal diffraction. ALD of Ru film was demonstrated using the new Ru metallorganic precursor and O2 as the Ru source and reactant, respectively, at the deposition temperatures of $300-350^{\circ}C$. Self-limited reaction behavior was observed as increasing Ru precursor and O2 pulse time, suggesting that newly developed Ru precursor is applicable for ALD process. Detailed discussions on the chemical and structural properties of Ru thin films as well as its growth behavior using new Ru precursor will be also presented.

  • PDF

Tetramethyl orthosilicate(TMOS) Synthesis by the Copper-Catalyzed Reaction of the Metallic Silicon with Methanol (I) - Effect of the Manufacturing Condition and the Composition of Contact Mass on TMOS Synthesis - (구리 촉매하에서 규소와 메탄올의 반응에 의한 Tetramethyl orthosilicate (TMOS) 합성(제1보) - 접촉물질의 제조방법 및 구성성분이 TMOS 합성에 미치는 영향 -)

  • Soh, Soon-Young;Han, Kee-Doo;Won, Ho-Youn;Chun, Yong-Jin;Lee, Bum-Jae;Yang, Hyun-Soo
    • Applied Chemistry for Engineering
    • /
    • v.10 no.2
    • /
    • pp.252-258
    • /
    • 1999
  • Tetramethyl orthosilicate (TMOS) was obtained by the direct synthesis of methanol with metallic silicon including copper compound as a catalyst and zinc compound as a promoter. The effects of the preheating temperature and the preparation method of the contact mass on TMOS synthesis were investigated. The composition effects of the contact mass which was composed of metallic silicon with copper catalyst and various metallic halide promoters including Zn, Sn or Cd compound were studied also. The best performance on TMOS synthesis was observed on a mixed bed reactor containing metallic silicon preheated with CuCl as a catalyst and $ZnCl_2$ as a promoter. When Cu/Si = 7 wt %, Zn/Cu = 7 wt % was mixed in a slurry phase and activated into contact mass at $380^{\circ}C$, the average selectivity was 87.2% in the silicon consumption of 69.2% at $220^{\circ}C$.

  • PDF

Formation and Removal of Trihalomethanes based on Characterization of Hydrophobic and Hydrophilic Precursors (전구물질의 소수성 및 친수성 특성에 따른 트리할로메탄의 생성과 제거에 관한 연구)

  • Jeon, Heekyung;Kim, Junsung;Choi, Yoonchan;Choi, Haeyeon;Chung, Yong
    • Journal of Korean Society on Water Environment
    • /
    • v.24 no.1
    • /
    • pp.123-128
    • /
    • 2008
  • The Dissolved Organic Carbon (DOC) existing in a water includes both hydrophobic and hydrophilic substances however, most of the discussion focuses on hydrophobic substances. The hydrophobic fraction was easily removed by absorption or coagulation more than hydrophilic fraction. Therefore, control of the hydrophilic fraction is very important in water treatment process. This study is to determine the variation of DOC, the removal efficiency of DOC, and Trihalomethane formation potential (THMFP) after each stage of water treatment process by fractionating Natural Organic Matters (NOM) into hydrophobic and hydrophilic substance. DOC from raw water was fractionated at acidic pH (pH<2) using XAD 8 resin column, into two fraction : hydrophobic substance (i.e. humic substance) adsorbed on XAD 8 and hydrophilic substance which represent the organics contained in the final effluent. THMFP was carried out according to the following set condition: Cl2/DOC=4 mg/mg, incubation at $25^{\circ}C$ in darkness, pH 7 adjust with HCl or NaOH as necessary, and 72hour-contact time. THMs analyzed in this study were chloroform, bromodichloromethane, dibromochloromethan, and bromoform. Sewage was almost evenly split between the hydrophobic (56%) and hydrophilic fraction (44%). But, Aldrich humic substance (AHS) was found to contain less hydrophilics (14%) than hydrophobics (86%). The formation of THMs may depend on the source which is characterized by the composition of organic matters such as AHS and sewage. The THMFP yield of sewage and AHS were assessed as follows. The value of the THMFP reaction yield, AHS $172.65{\mu}g/mg$, is much higher than that of sewage $41.68{\mu}g/mg$. This illustrates possible significant difference in THMFP according to the component type and the proportion of organic matter existing in water source. Apparently AHS react with chlorine to produce more THMFP than do the smaller molecules found in sewage. Water treatment process may reduce THMFP, nevertheless residual DOC (the more hydrophilic substance) has significant THMFP. Further reduction in organic halide precursors requires application of alternative treatment techniques.

Long-term Stability of Perovskite Solar Cells with Inhibiting Mass Transport with Buffer Layers (물질이동 억제 버퍼층 형성을 통한 페로브스카이트 태양전지 장기 안정성 확보)

  • Bae, Mi-Seon;Jeong, Min Ji;Chang, Hyo Sik;Yang, Tae-Youl
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.28 no.3
    • /
    • pp.17-24
    • /
    • 2021
  • Perovskite solar cells (PSCs) can be fabricated through solution process economically with variable bandgap that is controlled by composition of precursor solution. Tandem cells in which PSCs combined with silicon solar cells have potential to reach high power conversion efficiency over 30%, however, lack of long-term stability of PSCs is an obstacle to commercialization. Degradation of PSCs is mainly attributed to the mass transport of halide and metal electrode materials. In order to ensure the long-term stability, the mass transport should be inhibited. In this study, we confirmed degradation behaviors due to the mass transport in PSCs and designed buffer layers with LiF and/or SnO2 to improve the long-term stability by suppressing the mass transport. Under high-temperature storage test at 85℃, PSCs without the buffer layers were degraded by forming PbI2, AgI, and the delta phase of the perovskite material, while PSCs with the buffer layers showed improved stability with keeping the original phase of the perovskite. When the LiF buffer and encapsulation were applied to PSCs, superior long-term stability on 85℃-85% RH dump heat test was achieved; efficiency drop was not observed after 200 h. It was also confirmed that 90.6% of the initial efficiency was maintained after 200 hours of maximum power tracking test under AM 1.5G-1SUN illumination. Here, we have demonstrated that the buffer layer is essential to achieve long-term stability of PSCs.

A Growth and Characterization of CsPbBr3 Thin Film Grown by Thermal Chemical Vapor Deposition (열화학기상증착법을 이용한 CsPbBr3 박막 성장 및 특성 연구)

  • Ga Eun Kim;Min Jin Kim;Hyesu Ryu;Sang Hyun Lee
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.30 no.2
    • /
    • pp.71-75
    • /
    • 2023
  • In this study, inorganic perovskite films with different compositions were grown by thermal chemical vapor deposition depending on the substrate and their optical properties were compared. Inorganic perovskite crystals were grown on SiO2/Si and c-Al2O3 substrates using CsBr and PbBr2, respectively, under the same growth conditions. Cs4PbBr6-CsPbBr3 crystallites were grown on the SiO2 with polycrystalline structure, while a CsPbBr3 (100) dominant thin film was formed on the c-Al2O3 substrate with single crystal structure. From the photoluminescence measurement, CsPbBr3 showed typical green emission centered at 534 nm with a full width at half maximum (FWHM) of about 91 meV. The Cs4PbBr6-CsPbBr3 mixed structure exhibits blue-shifted emission at 523 nm with a narrow FWHM of 63 meV and a fast decay time of 6.88 ns. These results are expected to be useful for application in photoelectric devices such as displays, solar cells, and light sensors based on inorganic metal perovskites.

Thermal and Electrochemical Stability of Morpholinium Ionic Liquids (모폴린계 이온성 액체의 열 및 전기화학적 안정성)

  • Kim, Hyun-Taek;Hong, Yeon Ki;Kang, Jeong Won;Lee, Young-Woo;Kim, Ki-Sub
    • Korean Chemical Engineering Research
    • /
    • v.50 no.4
    • /
    • pp.702-707
    • /
    • 2012
  • During the last few decades, toxic chemicals used in various industries have caused global pollution and the side products such as carbon dioxide and methane gas have contributed to global warming. Thus, it is desirable to develop new alternative solvents. It is well known that ionic liquids display a variety of environmentally friendly physical properties: nonvolatile, nonflammable, wide electrochemical windows, high inherent conductivities, wide thermal operating ranges, chemically inert, and limited miscibilities with organic solvents. Because of these characteristics, ionic liquids are promising candidates as solvents for synthetic chemistries, catalysis, and gas separations. In this study, we synthesized morpholiunium salts as N-ethyl-N-methylmorpholine Bromide, N-butyl-N-methylmorpholine Bromide, N-octyl-N-methylmorpholine Bromide, N-ethyl-N-methylmorpholine Tetrafluoroborate, N-butyl-N-methylmorpholine Tetrafluoroborate, N-octyl-N-methylmorpholine Tetrafluoroborate, N-ethyl-N-methylmorpholine Hexafluorophosphate, N-butyl-N-methylmorpholine Hexafluorophosphate, and N-octyl-N-methylmorpholine Hexafluorophosphate. The melting points, decomposition temperatures and electrochemical stabilities of the salts were measured by DSC, TGA, and CV, respectively. The salts with halide anion showed high melting points ($150{\sim}200^{\circ}C$), low decomposition temperatures ($200{\sim}230^{\circ}C$), narrow electrochemical stabilities (3.4~3.6 V). The synthesized salts with inorganic anions, on the other hand, presented low melting point ($50{\sim}110^{\circ}C$), high decomposition temperatures ($250{\sim}380^{\circ}C$), wide electrochemical stabilities (6.1~6.3 V). We also found that the properties depend on the length of the carbon chain.