• Title/Summary/Keyword: V2C

Search Result 9,803, Processing Time 0.047 seconds

Ethanol Production by Separate Hydrolysis and Fermentation and Simultaneous Saccharification and Fermentation Using Saccharina japonica (Saccharina japonica를 이용한 전처리 및 분리당화발효와 동시당화발효로부터 에탄올 생산)

  • Kim, Min-Ji;Kim, Sung-Koo
    • KSBB Journal
    • /
    • v.27 no.2
    • /
    • pp.86-90
    • /
    • 2012
  • Ethanol fermentations were carried out using simultaneous saccharification and fermentation (SSF) and separated hydrolysis and fermentation (SHF) processes with monosaccharides from seaweed, Saccharina japonica (sea tangle, Dasima) as the biomass. The pretreatment was carried out by thermal acid hydrolysis with $H_2SO_4$ or HCl. Optimal pretreatment condition was determined at 10% (w/v) seaweed slurry with 37.5 mM $H_2SO_4$ at $121^{\circ}C$ for 60 min. To increase the yield of saccharfication, isolated marine bacteria Bacillus sp. JS-1 was used and 48 g/L of reducing sugar were produced. Ethanol fermentation was performed using SSF and SHF process with Pachysolen tannophilus KCTC 7937. The ethanol concentration was 6.5 g/L by SSF and 6.0 g/L by SHF.

Electronic Interaction between Metals Accross Conjugated Hydrocarbon Chain (공액계 탄화수소 사슬을 통한 금속원자간 전자적 상호작용)

  • Kim, Sun-Kyu;Chung, Min-Chul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2004.07b
    • /
    • pp.1037-1041
    • /
    • 2004
  • 공액계 유기가교로서 butadiene을 사용한 이핵 유기금속착체를 합성하였고, 합성된 유기금속착체 화합물에 대한 구조적 특징과 두 금속간의 전기화학적 특성에 관한 연구를 수행하였다. $[Cp*Fe(CO)_2]_2-({\mu}-CH=CH-CH=CH)$ 착체는 $Cp*(CO)_2$FeK와 cis-3,4-dichlorocyclobutene과의 반응으로 합성하였고, 이 착체에 결합된 CO기는 UV 광반응하에서 $PPh_3$로 치환시켜 $[Cp*Fe(CO(PPh)_3]_2-({\mu}-CH=CH-CH=CH)$를 합성하였다. 합성된 착체에 대한 전기화학적 특성을 파악하기 위해 CV 실험결과, 전위차 ${\Delta}E^{\circ}=0.575{\sim}0.605$ V이고 $K_c$값은 $109{\sim}1010$으로 매우 큰 값을 얻음으로서 두 금속간의 상호작용이 탄화수소사슬을 통해 활발하게 이루어지고 있음을 알수가 있었다.

  • PDF

Triethanolamine 질산鹽 基礎液中의 鉛(II)의 폴라로그라프波에 對하여

  • Kim, Hwang-Am
    • Journal of the Korean Chemical Society
    • /
    • v.6 no.2
    • /
    • pp.108-112
    • /
    • 1962
  • Lead ion gives a well-defined wave with $E_{1/2}$=-0.57V(vs. S.C.E.) from a base electrolyte consisting of 0.1M TEA=0.5M$KNO_3$=0.0002% methl red. (pH 9.8).The reduction wave of lead is lead(II) to lead(0) and electrode reaction of this wave diffusion controlled.Its diffusion current constant is 2.45 and temperature coefficient of this wave is about 1.2%.Under above conditions, diffusion current is proportional to the concentration of lead in the range of $10^{-3}$ ~$10^{-4}$ M.

  • PDF

Fatigue Behavior of Large Scale Tubular Joint for API 2W Gr. 50 Steel (API 2W Gr.50 강재를 이용한 대형 Tubular Joint 피로성능평가)

  • Im, Sung-Woo;Chang, In-Hwa;Jo, Chul-Hee;Park, Kwan-Kyu
    • Journal of Ocean Engineering and Technology
    • /
    • v.19 no.3
    • /
    • pp.54-58
    • /
    • 2005
  • Large-scale model tests of welded tubular K-joints were carried out to observe the fatigue behavior of API 2W Gr.50 steel produced by POSCO. The fatigue crack behaviors for various loading conditions were measured and investigated around the critical joint sections. The experimental results have been verified with numerical approaches and were also compared with the IIW, DnV RP-C203 and API RP 2A-WSD design curves. The hot-spot stress method was applied in the study. The SCF factor for tubular K-joint was also obtaine.

Special Right Jacobson Radicals for Right Near-rings

  • Rao, Ravi Srinivasa;Prasad, Korrapati Siva
    • Kyungpook Mathematical Journal
    • /
    • v.54 no.4
    • /
    • pp.595-606
    • /
    • 2014
  • In this paper three more right Jacobson-type radicals, $J^r_{g{\nu}}$, are introduced for near-rings which generalize the Jacobson radical of rings, ${\nu}{\in}\{0,1,2\}$. It is proved that $J^r_{g{\nu}}$ is a special radical in the class of all near-rings. Unlike the known right Jacobson semisimple near-rings, a $J^r_{g{\nu}}$-semisimple near-ring R with DCC on right ideals is a direct sum of minimal right ideals which are right R-groups of type-$g_{\nu}$, ${\nu}{\in}\{0,1,2\}$. Moreover, a finite right $g_2$-primitive near-ring R with eRe a non-ring is a near-ring of matrices over a near-field (which is isomorphic to eRe), where e is a right $g_2$-primitive idempotent in R.

Diffusion Coefficient of Iron in ZnSe Polycrystals from Metal Phase for mid-IR Gain Medium Application

  • Jeong, Junwoo;Myoung, NoSoung
    • Applied Science and Convergence Technology
    • /
    • v.23 no.6
    • /
    • pp.371-375
    • /
    • 2014
  • Diffusion coefficient of Fe in polycrystalline host ZnSe as a mid-IR gain medium has been measured in the annealing temperature ranges of 850 to $950^{\circ}C$. The synthesis of the samples was carried out in quartz ampoule in which the Fe thin film deposited by physical vapor evaporation method on the ZnSe. One can realize that the diffusion coefficient strongly depends on the surface active surfactants through the cleaning process and the substrate temperature during the thin film deposition leading to $2.04{\times}10^{-9}cm^2/s$ for $Fe^{2+}:ZnSe$. The Annealing temperature dependence of the Fe ions diffusion in ZnSe was used to evaluate the activation energy, $E_a$=1.39 eV for diffusion and the pre-exponential factor $D_0$ of $13.5cm^2/s$.

Enhancement of the Ferroelectric Properties of Pb(La1Ti)O3 Thin Films with Pb(La1Ti)O3Buffers Fabricated by Pulsed Laser Deposition (PLT buffer층의 삽입에 따른 강유전 PZT박막의 특성 향상)

  • Lim, Sung-Hoon;Lee, Eun-Sun;Chung, Hyun-Woo;Jeon, Kyung-Ah;Lee, Sang-Yeol
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.18 no.2
    • /
    • pp.105-108
    • /
    • 2005
  • The Pb(Zr,Ti)O$_3$ thin films were fabricated with Pb(La,Ti)O$_3$ buffers in-situ onto Pt/Ti/SiO$_2$/Si substrates by pulsed laser deposition method. We have observed the increase of the remanent polarization using PLT buffers. The remanent polarization value of 33.4 $\mu$C/$\textrm{cm}^2$ and the coercive field value of 66.4 kV/cm were obtained when the PLT tufter was deposited for 15 seconds. Enhancement of the polarization is resulted from the enhanced orientation of PZT thin film because of the PLT buffet layer.

A study on the optical and the electrical properties of octadecylviologen-(TCNQ$^{[-10]}$ )$_2$ LB films (Octadecylviologen-(TCNQ$^{[-10]}$ )$_2$LB막의 광학 및 전기적 특성 연구)

  • 박제상;이승엽;이용수;신동명;김태완;강도열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1996.05a
    • /
    • pp.170-173
    • /
    • 1996
  • The optical and the electrical properties of octadecylviologen-(TCNQ$\^$-/)$_2$LB(Langmuir-Blodgett) films have been studied. The films were made at 25mN/m with Y-type formation using kuhn type apparatus. According to a study of UV/visible absorption spectra, DS C, ESR, and I-V characteristics depending on temperatures, there is an internal change in OV-(TCNQ$\^$-/)$_2$ LB films near 350K. We have observed a status of Langmuir films using Brewster angle microscope at room temperature.

  • PDF

multi-stack gate dielectric 구조를 통한 LTPS TFT 특성

  • Baek, Gyeong-Hyeon;Jeong, Seong-Uk;Jang, Gyeong-Su;Park, Hyeong-Sik;Lee, Won-Baek;Yu, Gyeong-Yeol;Lee, Jun-Sin
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.08a
    • /
    • pp.200-200
    • /
    • 2010
  • 이 논문에서는 field-effect mobility를 향상시키기 위해 triple-layer (SiNx/SiO2/SiOxNy stack 구조)를 gate dielectric material 로 LTPS TFTs에 적용하였다. 이는 플라즈마 처리 기법과 적층구조의 효과적인 in-situ 공정을 이용하여 interface trap과 mobile charge를 낮추어 높은 이동도의 결과를 생각하고 실험하였다. 실험은 SiO2 gatedielectric과 triple-gate dielectric의 C-V curve를 1 MHz의 주파수에서 측정하였다. 또한 Transfer characteristics를 single SiO2 gatedielectric과 triple-gate dielectric of SiNx/SiO2/SiOxNy를 STA 장비를 이용해 측정하였다. 위의 측정을 통해 threshold voltage, mobility, subtheshold swing, driving current, ON/OFF current ratio를 비교 분석하였다.

  • PDF

A Study on the Development of Anode Material for Molten Carbonate Fuel Cell -Ni-Co anode- (용융탄산염 연료전지의 양극 및 대체재료의 제작에 관한 연구-Ni-Co양극에 관하여-)

  • 황상문;김선진;강성군
    • Journal of Surface Science and Engineering
    • /
    • v.27 no.3
    • /
    • pp.166-175
    • /
    • 1994
  • The effect of Co addition on the electrochemical performance and structural stability of porous Ni anode for molten carbonate fuel cell(MCFC) was evaluated by the anodic polarization and the sintering test in the simulated MCFC anode condition ($650^{\circ}C$, 80% $H_2$+20%$CO_2$). The anode current density ranged from 110mA/$cm^2$ to 144mA/$cm^2$ was obtained at +100mV overpotential by additions of Co up to 10 wt.%. The sintering resistance of Ni-Co anodes was higher than that of the pure Ni anode. The increase of sintering resistance seemed to be to the lower diffusion coefficient of Co than that of Ni.

  • PDF