• Title/Summary/Keyword: In-situ reaction

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In Situ Crosslinked Ionic Gel Polymer Electrolytes for Dye Sensitized Solar Cells

  • Shim, Hyo-Jin;Kim, Dong-Wook;Lee, Chang-Jin;Kang, Yong-Ku;Suh, Dong-Hack
    • Macromolecular Research
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    • v.16 no.5
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    • pp.424-428
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    • 2008
  • We prepared an ionic gel polymer electrolyte for dye-sensitized solar cells (DSSCs) without leakage problem. Triiodide compound (BTDI) was synthesized by the reaction of benzene tricarbonyl trichloride with diethylene glycol monotosylate and subsequent substitution of tosylate by iodide using NaI. Bisimidazole was prepared by the reaction of imidazole with the triethylene glycol ditosylate under strongly basic condition provided by NaH. BTDI and bisimidazole dissolved in an ionic liquid were injected into the cells and permeated into the $TiO_2$ nanopores. In situ crosslinking was then carried out by heating to form a network structure of poly(imidazolium iodide), thereby converting the ionic liquid electrolytes to a gel or a quasi-solid state. A monomer (BTDI and bisimidazole) concentration in the electrolytes of as low as 30 wt% was sufficient to form a stable gel type electrolyte. The DSSCs based on the gel polymer electrolytes showed a power conversion efficiency of as high as 1.15% with a short circuit current density of $5.69\;mAcm^{-2}$, an open circuit voltage of 0.525 V, and a fill factor of 0.43.

The preliminary evaluation of semi-quantitative analysis by in situ pre-chromatographic derivatization of amines and image analysis in TLC (TLC상 분리 전 직접적 유도체화 반응과 이미지 분석을 통한 아민 화합물의 반정량분석을 위한 선행평가)

  • Kim, Younsu;Choi, Sung-Woon
    • Analytical Science and Technology
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    • v.28 no.2
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    • pp.79-85
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    • 2015
  • A preliminary experiment was performed to develop a fast, convenient, and economical semi-quantitative method of analyzing amphetamine-like amines from images of derivatives. These were generated from the reaction (in situ, co-spot) of three amphetamine-like compounds with three derivatization reagents on a TLC plate. The attempt was made to optimize the reaction conditions for an efficient derivatization reaction, and TLC images taken by a digital camera were analyzed using two types of image analysis program (CP Atlas 2.0 and ImageJ) for repeatability (RSD, %) and linearity (R2). Then, their results were compared. For efficient derivatization, the reaction conditions needed to be modified. The results of image analysis of each of the samples at two different concentrations (0.5 mg/mL and 0.01 mg/mL) showed that the RSD values for reaction repeatability were in the range of 0.69-5.50%. From the calibration curves between the area of the derivative and the concentration of amines, the R2 values (R2 > 0.9906) for good linear correlation were found to be high, in a concentration range of 0.1-0.005 mg/mL of amines. In addition, the two programs demonstrated little difference in the analysis of repeatability and linearity of the derivatization, so that the current method has the potential to be used for the semi-quantitative analysis of amines.

Thermal Decomposition Reaction of Gas-phase Uranyl Complexes as Studied by in-Situ IR Spectroscopy

  • Cho, Young-Hwan;Choi, In-Kyu;Kim, Won-Ho
    • Proceedings of the Korean Nuclear Society Conference
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    • 2002.05a
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    • pp.420.1-420
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    • 2002
  • Thermal decomposition reaction of gas-phase UO2(hfacac)2. THF was investigated in a static cell. IR spectroscopic method was used to study the thermal decomptsition of gas phase uranyl complexes. The decomposition reaction products were separated by using thermal-gradient fractional sublimation method utilizing the differences in their volatility.

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A New Method for Determination of Enzyme Reaction and Activity of Lysozyme with UV-Spectrophotometer (UV-분광광도계를 이용한 새로운 Lysozyme의 효소반응 및 활성측정법 연구)

  • Kim, Woon-Soo;Kim, Yong-Wook;Kim, Woo-Sik
    • Applied Chemistry for Engineering
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    • v.9 no.6
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    • pp.857-863
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    • 1998
  • A simple and new experimental method for determination of lysozyme-M. lysodeikticus cell lysis reaction and lysozyme activity was suggested using Beer's law. The UV transmittance of the solution changed with the concentration of M. lysodeikticus and the relationship between the UV transmittance and M. lysodeikticus cell concentration followed Beer's Law. In addition, it was experimentally proven that the UV transmittance of the solution was not influenced by the lysozyme concentration and product of the lysis reaction. During the lysozyme-M. lysodeikticus cell lysis reaction, thus, M. lysodeikticus cell concentration in the solution could be measured in-situ by UV-spectrophotometer. By using these experimental data, kinetic Parameters of the Michaelis-Menten equation for the lysozyme-M. lysodeikticus cell 1ysis reaction was simply determined The maximum reaction rate constant ($k_3$) and Michaelis-Menten constants were $0.1734sec^{-1}$ and $9.83{\times}10^{-6}M$ respectively. The activity of the lysozyme could also be obtained with this experiment because the lysis reaction rate of the 1ysozyme depended on its activity.

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Kinetics of veratryl alcohol oxidation by lignin peroxidase and in-situ generated $H_2O_2$ in an electrochemical reactor

  • Lee, Gi-Beom;Gu, Man-Bok;Mun, Seung-Hyeon
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.524-527
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    • 2000
  • An electroenzymatic system to oxidize veratryl alcohol of on electrodes with in-situ generated hydrogen peroxide was studied. We investigated hydrogen peroxide generation, current efficiency, and veratryl alcohol oxidation in the electrode system at various conditions. The reaction rates of veratryl alcohol oxidation were compared in an electrochemical, an electroenzymatic, and an usual biochemical systems to prove the concept of electroenzymatic oxidation.

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INFRARED ABSORPTION MEASUREMENT DURING LOW-TEMPERATURE PECVD OF SILICON-OXIDE FILMS

  • Inoue, Yasushi;Sugimura, Hiroyuki;Takai, Osamu
    • Journal of the Korean institute of surface engineering
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    • v.32 no.3
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    • pp.297-302
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    • 1999
  • In situ measurement of infrared absorption spectra has been performed during low-temperature plasma-enhanced chemical vapor depositiion of silicon-oxide films using tetramethoxysilane as a silicon source. Several absorption bands due to the reactant molecules are clearly observed before deposition. In the plasma, these bands completely disappear at any oxygen mixing ratio. This result shows that most of the tetramethoxysilane molecules are dissociated in the rf plasma, even C-H bonds. Existence of Si-H bonds in vapor phase and/or on the film surface during deposition has been found by infrared diagnostics. We observed both a decrease in Si-OH absorption and an increase in Si-O-Si after plasma off, which means the dehydration condensation reaction continues after deposition. The rate of this reaction is much slower than the deposition ratio of the films.

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Reaction process in electrochromism of tungsten oxide thin films

  • An, Il-Sin;Lee, Chang-Hyo;Lim, Won-Taeg
    • Journal of Korean Vacuum Science & Technology
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    • v.2 no.2
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    • pp.85-91
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    • 1998
  • The electrochromic behaviors of de-magnetron sputtered tungsten oxide thin films were investigated during coloration and bleach cycles using in situ real-time spectroscopic ellipsometry. Effective medium approximation and least-squares regression analyses were employed to investigate the electrochromic process. The optical properties of the tungsten oxide film were analyzed using the oscillator model and the evolution of the process using a reaction-limited model. In these analyses, we found that two different reaction rates were associated with the process. We ascribe this behavior to the microstructure of this films.

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A Facile Preparation of 2-(2-Hydroxyethyl)homoallenylsilanes Using In Situ Generated Homoallenylindium Reagent

  • Lee, Pil Ho;Bang, Geuk Chan;An, Hyo Sun;Lee, Gu Yeon
    • Bulletin of the Korean Chemical Society
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    • v.22 no.12
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    • pp.1385-1389
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    • 2001
  • In situ generated homoallenylindium reagents derived from the reaction of indium with 4-bromo-3-[(tri-methylsilyl) methyl]-1,2-butadiene reacted with a variety of aldehydes in DMF to produce 2-(2-hydroxy-ethyl) homoallenylsilanes at room temperatu re in good to excellent yields. 2- or 3-Hydroxybenzaldehyde that contains labile hydrogen was reacted with homoallenylindium reagent to provide the homoallenylsilanes. In the case of 4-formylbenzoic acid, the desired compound was produced in 88% yield. 4-Bromo-3-[(trimethyl-silyl) methyl]-1,2-butadiene was prepared from monoacetylation and mesylation of 2-butyn-1,4-diol, addition of trimethylsilylmethyl anion, saponification and mesylation followed by Finkelstein reaction.

In Situ Estimation of the Constituents of Green Soybean (Edamame) Pod using Near-Infrared Transmission Spectroscopy

  • Suzuki, Michiru;Katahira, Mitsuhiko;Natsuga, Motoyasu
    • Journal of Biosystems Engineering
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    • v.39 no.4
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    • pp.352-356
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    • 2014
  • Purpose: We estimated the dietary qualities of green soybean (edamame) by using a specialized NIR transmission spectrometer to determine the constitutive properties of the soybean, such as the sucrose content and ninhydrine reaction quantity (NRQ; defined by the ninhydrine reaction, which has a high positive correlation with the total free amino acids), with the purpose of establishing a quality assurance system. Methods: We used a newly developed spectrometer probe that enables in situ estimation of the constituents of the soybean. Results: The calibration results obtained using a wavelength range of 760-960 nm were characterized by $R^2$ = 0.57 and standard error of cross-validation (SECV) of 0.78% for sucrose, and $R^2$ = 0.59 and SECV = 0.35% for NRQ. Conclusions: These results are inferior to those of our previous study obtained using a specialized bench-type transmission spectrometer. The poorer results are attributed to several possible reasons, including the effect of direct sunlight and the unstable sample presentation. We plan to conduct further study using improved optical layout and sample presentation.

A Study on the Manufacture of WC MMCs by In-situ Reaction Process(1);The Formation Mechanism of Interfacial Reaction Layer in Cast-bonded Cast iron/W wire and Its Structure (기지내 반응법에 의한 WC 복합재료의 제조에 관한 연구(1);주조접합된 주철/텅스텐 와이어의 계면반응층 생성기구와 조직특성)

  • Park, Heung-Il;Kim, Chang-Up;Huh, Bo-Young;Lee, Sung-Youl;Kim, Chang-Gyu
    • Journal of Korea Foundry Society
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    • v.15 no.3
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    • pp.272-282
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    • 1995
  • Iron-based metal matrix composites have been recently investigated for the use of inexpensive abrasion resistance material. This paper carried out to investigate the in-situ reaction effects on the microstructural characteristics and the formation mechanism of tungsten carbides in a white cast iron matrix. The specimens of Fe-3.2%C-2.8%Si alloy cast-bonded with tungsten wire were cast in the metal mold and isothermally heat treated at $950^{\circ}C$ up to 48 hours. The typical microstructure of heat treated specimens showed the reaction layer of WC at the interface of tungsten wire and the carbon depletion zone between the WC layer and the matrix. During the formation of WC layer, if the carbon supply is insufficient due to the decarburization of matrix or the isolation of matrix by cast-bonded W wires, the reaction layer develops coarse hexagonal crystalline WC. From the microstructural investigation, it was found that the volume of WC layer and the carbon depletion zone increased linearly with the isothermal heat treating time. This results supported that the formation rate of WC in the white cast iron matrix is controlled by the interfacial reaction with a constant reaction rate.

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