• Title/Summary/Keyword: Si absorption

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Study on the Salt Tolerance of Rice and Other Crops in Reclaimed 2. On the Salt Tolerance of Chinese Cabbage and Cabbage in Various Salty Conditions (간척지에서 수도 및 기타작물의 내염성에 관한 연구 2. 여러 가지 염분조건에서 배추와 양배추의 내염성에 관하여)

  • 임형빈
    • Journal of Plant Biology
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    • v.12 no.3
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    • pp.8-14
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    • 1969
  • Salt tolerances of Chinese cabbage and cabbage were observed by means of the sand culture and field experiment. The point of 50% yield reduction of Chinese Cabbage was 1% of salt concentration in sand culture. The Na absorption in the salty upland conditions was increased but the absorption of Ca, Mg were interrupted as the salt concentration was raised and there were no differences in the absorption of N and P. The Si absorption was increased at low salty conditions, but the salt concentration was raised, the absorption was interrupted drastically. The cabbage was more stronger salt tolerance than Chinese cabbage, and it was possible to prevent the salt damage significantly by planting on sloping beds instead of planting on the double-row beds in field condition.

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$SO_2/O_2$ Separation Process with EMIm[$EtSO_4$] in SI Cycle for the Hydrogen Production by Water Splitting (물분해 수소제조를 위한 SI cycle에서의 EMIm[$EtSO_4$]를 이용한 $SO_2/O_2$ 분리공정)

  • Lee, Ki-Yong;Kim, Hong-Gon;Jung, Kwang-Deog;Kim, Chang-Soo
    • Journal of Hydrogen and New Energy
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    • v.22 no.1
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    • pp.13-20
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    • 2011
  • $SO_2$ has been absorbed and separated selectively by an ionic liquid from $SO_2/O_2$ mixture decomposed from sulfuric acid during the thermochemical SI cycle for the water splitting. In order to design and operate high pressure $SO_2/O_2$ separation system, the solubility of $SO_2$ in [EMIm]$EtSO_4$ (1-ethyl-3-methylimidazolium ethylsulfate) has been measured by Magnetic Suspension Balance at high pressure and temperature. Based on the measured solubility, a pressurized separation system was set up and operated. 194 L/h of $SO_2$($SO_2:O_2$=0.65:1) has been separated with 99.85% of $O_2$ at the vent of absorption tower, which is 22.7% of the theoretically ideal capacity of the system. This discrepancy results from the reduced contact between the gaseous $SO_2$ and the ionic liquid. Increased $SO_2$ supply, scale-up of the absorption column, and a faster ionic liquid circulation speed were suggested to improve the separation capacity.

IR Absorption Property in NaNo-thick Nickel Cobalt Composite Silicides (나노급 두께의 Ni50Co50 복합 실리사이드의 적외선 흡수 특성 연구)

  • Song, Oh Sung;Kim, Jong Ryul;Choi, Young Youn
    • Korean Journal of Metals and Materials
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    • v.46 no.2
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    • pp.88-96
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    • 2008
  • Thermal evaporated 10 nm-$Ni_{50}Co_{50}$/(70 nm-poly)Si films were deposited to examine the energy saving properties of silicides formed by rapid thermal annealing at temperature ranging from 500 to $1,100^{\circ}C$ for 40 seconds. Thermal evaporated 10 nm-Ni/(70 nm-poly)Si films were also deposited as a reference using the same method for depositing the 10 nm-$Ni_{50}Co_{50}$/(70 nm-poly)Si films. A four-point probe was used to examine the sheet resistance. Transmission electron microscopy (TEM) and X-ray diffraction XRD were used to determine cross sectional microstructure and phase changes, respectively. UV-VIS-NIR and FT-IR (Fourier transform infrared spectroscopy) were used to examine the near-infrared (NIR) and middle-infrared (MIR) absorbance. TEM analysis confirmed that the uniform nickel-cobalt composite silicide layers approximately 21 to 55 nm in thickness had formed on the single and polycrystalline silicon substrates as well as on the 25 to 100 nm thick nickel silicide layers. In particular, nickel-cobalt composite silicides showed a low sheet resistance, even after rapid annealing at $1,100^{\circ}C$. Nickel-cobalt composite silicide and nickel silicide films on the single silicon substrates showed similar absorbance in the near-IR region, while those on the polycrystalline silicon substrates showed excellent absorbance until the 1,750 nm region. Silicides on polycrystalline substrates showed high absorbance in the middle IR region. Nickel-cobalt composite silicides on the poly-Si substrates annealed at $1,000^{\circ}C$ superior IR absorption on both NIR and MIR region. These results suggest that the newly proposed $Ni_{50}Co_{50}$ composite silicides may be suitable for applications of IR absorption coatings.

Electrical characteristics of low-k SiOCH thin film deposited by BTMSM/$O_2$ high flow rates (BTMSM/$O_2$ 고유량으로 증착된 low-k SiOCH 박막의 전기적인 특성)

  • Kim, Min-Seok;Hwang, Chang-Su;Kim, Hong-Bae
    • Journal of the Semiconductor & Display Technology
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    • v.7 no.1
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    • pp.41-45
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    • 2008
  • We studied the electrical characteristics of low-k SiOCR interlayer dielectric(ILD) films fabricated by plasma enhanced chemical vapor deposition (PECVD). The precursor bis-trimethylsilylmethane (BTMSM) was introduced into the reaction chamber with the various flow rates. The absorption intensities of Si-O-$CH_x$, bonding group and Si-$CH_x$, bonding group changed synchronously for the variation of precursor flow rate, but the intensity of Si-O-Si(C) responded asynchronously with the $CH_x$, combined bonds. The SiOCH films revealed ultra low dielectric constant around 2.1(1) and reduced further below 2.0 by heat treatments.

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Estimation of the Light Absorption Contribution for Asian Dust and Polluted Particles at Gosan, Jeju during the Asian Dust Episode in the Spring 2011 (2011년 봄 황사시기 제주도 고산에서의 황사와 오염입자의 광흡수 기여도 산정)

  • Lee, Si-Hye;Kim, Sang-Woo;Yoon, Soon-Chang
    • Journal of Korean Society for Atmospheric Environment
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    • v.28 no.4
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    • pp.411-422
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    • 2012
  • Ground-based in-situ measurements of aerosol optical properties at Gosan climate observatory have been analyzed to investigate the optical contribution of Asian dust and polluted particles on light absorption in springtime 2011. During the Asian dust episode, the contribution of Asian dust particle to aerosol absorption coefficient estimated about 45% at 370 nm and about 23% at 520 nm. Especially, black carbon in dust plume contributes about 48% to aerosol light absorption at 520 nm since the airmass are transported from the Gobi and inner Mongolia deserts, and this airmass comes across the northeastern coast of China, near the Shandong Peninsula. In pollution case, the contributions of dust particle and black carbon to aerosol absorption coefficient estimated about 41% and 11% at 370 nm, respectively. However, pollution case shows the highest light absorption of 48% for brown carbon at 370 nm, which indicates the significantly high mass concentration of organic carbon ($6.3{\pm}2.2{\mu}g\;m^{-3}$) in pollution plume can contribute to the increase of light absorption at near-UV spectral region.

SPC Growth of Si Thin Films Preapared by PECVD (PECVD 방법으로 증착한 Si박막의 SPC 성장)

  • 문대규;임호빈
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1992.05a
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    • pp.42-45
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    • 1992
  • The poly silicon thin films were prepared by solid phase crystallization at 600$^{\circ}C$ of amorphous silicon films deposited on Corning 7059 glass and (100) silicon wafer with thermally grown SiO$_2$substrate by plasma enhanced chemical vapor deposition with varying rf power, deposition temperature, total flow rate. Crystallization time, microstructure, absorption coefficients were investigated by RAMAN, XRD analysis and UV transmittance measurement. Crystallization time of amorphous silicon films was increased with increasing rf power, decreasing deposition temperature and decreasing total flow rate.

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Preparation and Characteristics of Te Fine Particles Doped SiO2 Glass Thin Films by Sol-gel Method (졸-겔법에 의한 Te 미립자 분산 SiO2 유리 박막의 제조와 특성)

  • Mun, Chong-Soo;Kang, Bong-Sang
    • Journal of the Korean Ceramic Society
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    • v.41 no.1
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    • pp.24-29
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    • 2004
  • Nanocomposite of Te doped $SiO_2$ films was prepared for the new functional materials like non-linear optic materials, selective absorption and transmission films. The effects of particle size and morphology with different hydrolysis conditions on the properties were examined with TGA/DTA. XRD. UV-spectrometer, SPM, SEM and EDS. It was found that Te/$SiO_2$ films showed high absorption peak at 550nm visible region by plasma resonance of Te fine particles. The Rm surface roughness of the films was about 2.5 nm and the size of Te particles was 5~10nm.

Effect of Silicon Oxynitride Matrix on the Optical Properties of Au Nanoparticles Dispersed Composite Film (실리콘 산화질화물 기지상 적용에 따른 Au 나노입자 분산 복합체 박막의 광학적 특성)

  • Cho, Sung-Hun;Lee, Kyeong-Seok
    • Korean Journal of Materials Research
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    • v.19 no.12
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    • pp.637-643
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    • 2009
  • In this study, we analyzed the effect of silicon oxynitride matrix on the optical properties of Au nanoparticles dispersed on composite film and explored the effectiveness of the silicon in fine tuning the refractive index of the composite film for applications in optical waveguide devices. The atomic fraction of nitrogen in $SiO_xN_y$ films was controlled by varying the relative flow ratio of nitrogen gas in reactive sputtering and was evaluated optically using an effective medium theory with Bruggeman geometry consisting of a random mixture between $SiO_2$ and $Si_3N_4$. The Au nanoparticles were embedded in the $SiO_xN_y$ matrix by employing the alternating deposition technique and clearly showed an absorption peak due to the excitation of surface plasmon. With increasing nitrogen atomic fraction in the matrix, the surface plasmon resonance wavelength shifted to a longer wavelength (a red-shift) with an enhanced resonance absorption. These characteristics were interpreted using the Maxwell-Garnett effective medium theory. The formation of a guided mode in a slab waveguide consisting of 3 $\mu$m thick Au:$SiO_xN_y$ nanocomposite film was confirmed at the telecommunication wavelength of 1550 nm by prism coupler method and compared with the case of using $SiO_2$ matrix. The use of $SiO_xN_y$ matrix provides an effective way of controlling the mode confinement while maintaining or even enhancing the surface plasmon resonance properties.

Effects of a Non-absorbable Gas on the Absorption Process in a Vertical Tube Absorber

  • Hur, ki-Joon;Jeong, Eun-Soo;Jeong, Si-Young
    • International Journal of Air-Conditioning and Refrigeration
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    • v.7
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    • pp.69-78
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    • 1999
  • Effects of a non-absorbable gas on the absorption process in a vertical tube absorber has been investigated numerically. The water vapor mixed with air is absorbed into LiBr/water solution film. The flow is assumed to be laminar and fully developed in both liquid and gas phases. The diffusion and energy equations were solved in both phases to give the temperature and concentrations, from which heat and mass fluxes were determined. The local absorption rate has been shown to decrease as the mass fraction of air in the water vapor increases. The vapor pressure of water at the liquid-vapor is interface reduced significantly since the non-absorbable gas accumulates near the interface. The effects of non-absorbable gases on absorption rate become larger as the mass flow rate of the vapor decreases. For a small amount of non-absorbable gases, the total absorption rate of water vapor increases as the mass flow rate of the vapor decreases. The total absorption rate increases as the mass flow rate of the vapor increases for large concentrations of non-absorbable gases at the inlet of an absorber.

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Characterization of Ultra Low-k SiOC(H) Film Deposited by Plasma-Enhanced Chemical Vapor Deposition (PECVD)

  • Kim, Sang-Yong
    • Transactions on Electrical and Electronic Materials
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    • v.13 no.2
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    • pp.69-72
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    • 2012
  • In this study, deposition of low-dielectric constant SiOC(H) films by conventional plasma-enhanced chemical vapor deposition (PECVD) were investigated through various characterization techniques. The results show that, with an increase in the plasma power density, the relative dielectric constant (k) of the deposited films decreases whereas the refractive index increases. This is mainly due to the incorporation of organic molecules with $CH_3$ group into the Si-O-Si cage structure. It is as confirmed by FT-IR measurements in which the absorption peak at 1,129 $cm^{-1}$ corresponding to Si-O-Si cage structure increases with power plasma density. Electrical characterization reveals that even after fast thermal annealing process, the leakage current density of the deposited films is in the order of $10^{-11}$ A/cm at 1.5 MV/cm. The reliability of the SiOC(H) film is also further characterized by using BTS test.