• Title/Summary/Keyword: Mo addition

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Characteristics of mycelial culture of Sparassis crispa (꽃송이버섯 균사배양적 특성)

  • Chang, Hyun-You;Choi, Seung-Oh
    • Journal of Mushroom
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    • v.2 no.3
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    • pp.163-167
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    • 2004
  • It shows that there is the fastest growth of S. crispa in the weak acid pH5. Also, it shows that S. crispa has the best environment in the MEF media. The next desirable one was as in this array: MES, MEI, YMF, YMM, YMT, YMB, YMI, MEA, PDA. The best fungi-growth of S. crispa is shown within the 0.2% addition of multi-mineral. The slow fungi-growth of S. crispa is shown within as the opposite. The phisical growth of S. crispa has a absolute need of comparatably large amount of P,K,N,S etc as inorganic minerals. In addition of that, as a minor element, Fe, Zn, Cu, Mo, Co, Mn, Cl etc are should be included. The best fungi-growth of S. crispa is shown within the 0.1% addition of biotin. The slow fungi-growth of S. crispa is shown within as the opposite. The best fungi-growth of S. crispa is shown within the 2% addition of fructose. The slow fungi-growth of S. crispa is shown within as the opposite.

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Redox Characteristics of $MO/Al_2O_3-ZrO_2$ [M=Ni and Cu] Mixed Metal Oxides ($MO/Al_2O_3-ZrO_2$ [M=Ni 및 Cu] 혼합 금속 산화물의 환원-산화 특성)

  • Ryu, Jae-Chun;Kim, Young-Ho;Park, Chu-Sik;Hwang, Gab-Jin;Kim, Jong-Won
    • Transactions of the Korean hydrogen and new energy society
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    • v.16 no.1
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    • pp.49-57
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    • 2005
  • [ $MO/Al_2O_3-ZrO_2$ ](M=Ni and Cu) mixed metal oxides were prepared using sol-gel method in order to investigate the applicability to the 2-step thermo-chemical water splitting process and their redox behaviors were studied by temperature programmed reaction(TPR) from room temperature to 900$^{\circ}C$ under 5% $H_2$/Ar for the reduction and $H_2O$/Ar for the oxidation, respectively. From the results, peaks of the reduction and the oxidation on temperature were shifted with the change of crystalline phases due to the addition of $Al_2O_3$ and $ZrO_2$. The intensities of the peaks were also increased with the increase of contents of NiO or CuO that could be considered as active species. In addition, based on the observation of SEM images before and after the redox test, it seemed that $Al_2O_3-ZrO_2$ added prevented high temperature sintering of active metal components such as Ni (or Cu) on the surface and played a role of dispersing the active species homogeneously in solid solution of mixed oxides.

Effect of Final Annealing Temperature on Microstructure and Creep Characteristics of Nb-containing Zirconium Alloys (Nb 첨가 Zr 합금의 미세조직과 Creep 특성에 미치는 마지막 열처리 온도의 영향)

  • Park, Yong-Gwon;Yun, Yeong-Gwon;Wi, Myeong-Yong;Kim, Taek-Su;Jeong, Yong-Hwan
    • Korean Journal of Materials Research
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    • v.11 no.10
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    • pp.879-888
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    • 2001
  • The effects of final annealing temperature on the microstructure and creep characteristics were investigated for the Zr-lNb-0.2X (X=0, Mo, Cu) and Zr-lNb- 1Sn-0.3Fe-0.1X (X=0, Mo, Cu) alloys. The microstructures were observed by using TEM/EDS, and grain size and distributions of precipitates were analyzed using a image analyzer. The creep test was performed at $400^{\circ}C$ under applied stress of 150 MPa for 10 days. The $\beta$-Zr was observed at annealing temperature above $600^{\circ}C$. In the temperature above$ 600^{\circ}C$, the grain sizes of both alloy systems appeared to be increased with increasing the final annealing temperature. The creep strengths of Zr-1Nb-1Sn-0.3Fe-0.1X alloys were higher than those of Zr-1Nb-0.2X ones due to the effect of solid solution hardening by Sn in Zr-lNb-lSn-0.3Fe-0.1X alloy system. Also, Mo addition showed the strong effect of precipitate hardening in both alloy systems. The creep strength rapidly decreased with increasing the annealing temperature up to $600^{\circ}C$. However, a superior creep resistance was obtained in the sample that annealed to have a second phase of $\beta$-Zr. It was considered that the appearance of $\beta$-Zr would play an important role in the strengthening mechanism of creep deformation.

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Understand the Molecular Orbital Theory on the Hydrolytic Reactivity of Herbicide Flumioxazine (제초제 Flumioxazine의 가수분해 반응성에 관한 분자 궤도론적 이해)

  • Sung, Nack-Do;Jung, Hoon-Sung
    • The Korean Journal of Pesticide Science
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    • v.8 no.4
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    • pp.265-271
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    • 2004
  • Hydrolytic reactivities of N-phenylphthalimid herbicide flumioxazine (S) were disccused using molecular orbital (MO) theoretical method. It is revealed that below pH 5.0, the protonation $(SH^+)$ to carbonyl oxygens atom $(O_{21})$ of 1,2-dicarboximino group by general acid catalysis $(k_A)$ with hydronium ion $(H_3O^+)$ proceeds via charge controled reaction. Whereas, the specific base catalysis $(k_{OH})$ with hydroxide anion via orbital controled reaction occurs above pH 8.0. We may concluded that in the range of pH $5.0\sim8.0$, the hydrolysis proceeds through nucleophilic addition elimination $(Ad_{N-E})$ reaction, these two reactions occur competitively.

A Study on the Bainite Phase Control of Direct-Quenched Low Carbon Steels (저탄소 직접 소입강의 베이나이트상 조절에 관한 연구)

  • An, Byeong-Gyu;Go, Yeong-Sang;Lee, Gyeong-Seop
    • Korean Journal of Materials Research
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    • v.6 no.8
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    • pp.841-851
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    • 1996
  • In a recent investigation, the formation of bainite phase in direct-quenched low carbon non heat-treated steel was reported. In this study the effects of bainite phase on the mechanical properties of direct-quenched microalloying steels were investigated. By isothermal transformation at $480^{\circ}C$ for 7 sec., volume fraction of bainite lath was 15~20%, and the UTS and impact energy were increased. In this case $B_{ll}$ and $B_{lll}$ type bainite was observed and the fractography of impact test specimen showed a ductile fracture tendency. Isothermal transformation for 100sec., yielded 30% volume fraction of granular bainite and the mechanical properties were decreased. The f ractography of impact test specimen showed a brittle fracture tendency. The addition of Mo was more effective than B for improving impact energy because amounts of boron aditions were restricted to considerably lower levels, typically 10~ 30ppm. From this study, it is predicted that 15~20% volume fraction of lath bainite on the direct quenching process is procduced by addition of Mo up to 1.2wt. % and controlling the finish forging proc¬ess at $1000^{\circ}C$ and using oil as direct quenching media. This will improve mechanical properties of the direct- quenched steel.

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Microstructural and Mechanical Properties of Ta-bearing 9%Cr Ferritic/Martensitic Steels (탄탈륨 함유 9%Cr 페라이트/마르텐사이트 강의 미세조직 및 기계적 특성)

  • Baek, Jong-Hyuk;Han, Chang-Hee;Kim, Sung-Ho;Lee, Chan-Bock;Hahn, Dohee
    • Korean Journal of Metals and Materials
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    • v.47 no.4
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    • pp.209-216
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    • 2009
  • It was evaluated that the microstructural and mechanical properties of Ta-bearing 9Cr-0.5Mo-2W ferritic/martensitic experimental steels. All the experimental steels showed the tempered martensitic microstructures, and $M_{23}C_6$ carbides, whose sizes were ranged from 200 to 300 nm, were easily observed at both boundaries of the prior austenite grain and the martensite lath. In addition, a relatively large Nb-rich MX carbonitrides were intermittently detected at the prior austenite grain boundaries, whereas a lot of Vrich MX carbonitrides, whose mean diameter was less than 50 nm, were observed randomly at both boundaries. Ta was mainly incorporated into the V-rich MX carbonitrides rather than the Nb-rich ones and their content was spanned from 5 to 20 at.%. Ta contents within the MX precipitates also increased as the content of Ta increased. Because the Ta addition into the steels would be attributed to the precipitation strengthening, solid solution strengthening and lath width reduction, it was shown that the mechanical properties, including hardness, tensile strength and creep rate of the 9%Cr-0.5Mo-2W steels were improved by the increase of Ta content. Especially, 9Cr-0.5Mo-2W-0.3V-0.05Nb-0.14Ta steel was revealed to be relatively excellent in the application for the SFR fuel cladding.

Mo,Cu-doped CeO2 as Anode Material of Solid Oxide Fuel Cells (SOFCs) using Syngas as Fuel

  • Diaz-Aburto, Isaac;Hidalgo, Jacqueline;Fuentes-Mendoza, Eliana;Gonzalez-Poggini, Sergio;Estay, Humberto;Colet-Lagrille, Melanie
    • Journal of Electrochemical Science and Technology
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    • v.12 no.2
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    • pp.246-256
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    • 2021
  • Mo,Cu-doped CeO2 (CMCuO) nanopowders were synthesized by the nitrate-fuel combustion method aiming to improve the electrical and electrochemical properties of its Mo-doped CeO2 (CMO) parent by the addition of copper. An electrical conductivity of ca. 1.22·10-2 S cm-1 was measured in air at 800℃ for CMCuO, which is nearly 10 times higher than that reported for CMO. This increase was associated with the inclusion of copper into the crystal lattice of ceria and the presence of Cu and Cu2O as secondary phases in the CMCuO structure, which also could explain the increase in the charge transfer activities of the CMCuO based anode for the hydrogen and carbon monoxide electro-oxidation processes compared to the CMO based anode. A maximum power density of ca. 120 mW cm-2 was measured using a CMCuO based anode in a solid oxide fuel cell (SOFC) with YSZ electrolyte and LSM-YSZ cathode operating at 800℃ with humidified syngas as fuel, which is comparable to the power output reported for other SOFCs with anodes containing copper. An increase in the area specific resistance of the SOFC was observed after ca. 10 hours of operation under cycling open circuit voltage and polarization conditions, which was attributed to the anode delamination caused by the reduction of the Cu2O secondary phase contained in its microstructure. Therefore, the addition of a more electroactive phase for hydrogen oxidation is suggested to confer long-term stability to the CMCuO based anode.

Effects of Additional Elements of the Mechanical Properties of HSLA Cast Steels (HSLA 주강의 기계적 성질에 미치는 첨가원소의 영향)

  • Park, Jai-Hyun;Kim, In-Bae
    • Journal of Korea Foundry Society
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    • v.20 no.5
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    • pp.307-315
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    • 2000
  • The effects of additional elements on the mechanical properties of HSLA cast steels such as hardness, tensile strength and charily impact energy have been investigated. Test results showed the mechanical properties of HSLA cast steels were superior to those of C-Mn cast steels. In case of the HSLA cast steels, HSLA cast steels with all addition of Nb, V, and Ti had more excellent tensile strength than those with individual addition of Nb, V, or Ti. The tensile strengths of HSLA cast steels were increased as the Mo contents were increased from 0.25% to 0.5%. These are attributed to the solution hardening and the change of the precipitation kinetics of NbC due to increased Mo contents. The tensile strength of HSLA cast steel was remarkablely increased as the manganese contents were increased from 0.65% to 1.2% and 1.5%, respectively. However, the optimum composition of HSLA cast steels to obtain the best compromise between tensile strength and charily impact energy compared to C-Mn cast steel was the additions of0.1% C and 1.2% Mn.

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Studies on the Enzyme of Rhizopus oryzae - Part I. Production of Acid Protease and Enzymatic Characteristics - (Rhizopus oryzae의 효소(酵素)에 관(關)한 연구(硏究) - 제(第)1보(報), 산성(酸性) Protease 생산(生産) 및 효소(酵素)의 특성(特性) -)

  • Hou, Won-Nyong;Chung, Man-Jae
    • Applied Biological Chemistry
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    • v.22 no.3
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    • pp.135-141
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    • 1979
  • These experiments were conducted to investigate the conditions of the acid protease production by Rhizopus oryzae and the characteristics of crude enzyme. The results obtained were as follows: 1. The optimum culture time and the optimum amount of added water to the wheat bran medium were about 48 hrs and $80{\sim}120%$, respectively. 2. The addition of $(NH_4)_6Mo_7O_{24},\;(NH_4)_2SO_4,\;NH_4NO_3$, casein, and albumin, respectively, as nitrogen sources to the wheat bran medium was effective. Of these, the optimum concentrations of addition of $(NH_4)_6Mo_7O_{24}$ and casein which were the most effective were 0.1% and 1.0%, respectively. 3. The addition of glucose, galactose, maltose, lactose, and soluble starch, respectively, as carbon sources to the wheat bran medium was effective. Of these, the optimum concentration of addition of glucose which was the most effective was 3.0%. 4. The addition of $KH_2PO_4$ as a phosphate salt to the wheat bran medium was effective. The optimum concentration of addition of $KH_2PO_4$ was 0.3%. 5. The optimum pH for the enzyme action was 2.4, the optimum temperature about $40^{\circ}C$, and the stable pH range $2.0{\sim}5.0$. The enzyme was stab1e below $40^{\circ}C$. 6. The enzyme activity increased rapidly for 10 minutes after addition, thereafter it increased slowly. 7. The enzyme activity increased rapidly to 2 ml of addition, but nearly did not increase at the amounts greater than 2ml.

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Stereo-based Robust Human Detection on Pose Variation Using Multiple Oriented 2D Elliptical Filters (방향성 2차원 타원형 필터를 이용한 스테레오 기반 포즈에 강인한 사람 검출)

  • Cho, Sang-Ho;Kim, Tae-Wan;Kim, Dae-Jin
    • Journal of KIISE:Software and Applications
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    • v.35 no.10
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    • pp.600-607
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    • 2008
  • This paper proposes a robust human detection method irrespective of their pose variation using the multiple oriented 2D elliptical filters (MO2DEFs). The MO2DEFs can detect the humans regardless of their poses unlike existing object oriented scale adaptive filter (OOSAF). To overcome OOSAF's limitation, we introduce the MO2DEFs whose shapes look like the oriented ellipses. We perform human detection by applying four different 2D elliptical filters with specific orientations to the 2D spatial-depth histogram and then by taking the thresholds over the filtered histograms. In addition, we determine the human pose by using convolution results which are computed by using the MO2DEFs. We verify the human candidates by either detecting the face or matching head-shoulder shapes over the estimated rotation. The experimental results showed that the accuracy of pose angle estimation was about 88%, the human detection using the MO2DEFs outperformed that of using the OOSAF by $15{\sim}20%$ especially in case of the posed human.