• Title/Summary/Keyword: $C_k$

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Decomposition Models of the Organic Matters in Cultural Media and the Litters in Forest (배양액에서의 유기물분해와 식물군락에서의 낙엽분해에 관한 모델)

  • 이웅상;장남기
    • Asian Journal of Turfgrass Science
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    • v.9 no.2
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    • pp.119-129
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    • 1995
  • Decomposition rates of glucose, starch, spinach leaves and litters in forests are calculated by equation dC dt=-kC(Co-1nC), dC- dt=$-kC^2$, and Olson's negative exponential decay model.dC dt = - kC =-kC(Co - InC) showed a very close fit to decomposition of the organic matters in cultural media by purified microorganisms and dC dt=$-kC^2$ to decomposition of the litters in forests. Key words: Organic matters, Cultural media, Glucose, Starch, Leaves, Litters.

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Research on the Oxidation-Protective Coatings for Carbon/Carbon Composites

  • Li, He-Jun;Fu, Qian-Gang;Huang, Jian-Feng;Zeng, Xie-Rong;Li, Ke-Zhi
    • Carbon letters
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    • v.6 no.2
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    • pp.71-78
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    • 2005
  • Anti-oxidation coatings are the key technique for carbon/carbon (C/C) composites used as the thermal structural materials. The microstructure and oxidation behavior of several kinds of high-performance ceramic coatings for C/C composites prepared in Northwestern Polytechnical University were introduced in this paper. It showed that the ceramic coatings such as SiC, Si-$MoSi_2$, SiC-$MoSi_2$, $Al_2O_3$-mullite-SiC and SiC/yttrium silicate/glass coatings possessed excellent oxidation resistance at high temperatures, and some of these coatings were characterized with excellent thermal shock resistance. The SiC-$MoSi_2$ coating system has the best oxidation protective property, which can effectively protect C/C composites from oxidation up to 1973 K. In addition, the protection and failure reasons of some coatings at high temperature were also provided.

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Interactions between Hydrodenitrogenation of Pyridine and Hydrodeoxygenation of m-Cresol over sulfided CoMo/γ-Al2O3 Catalyst (황화 CoMo/γ-Al2O3 촉매상에서 수첨탈질반응과 수첨탈산소 반응의 상호작용)

  • Kim, Hak-Soo;Park, Hea-Kyung;Kim, Kyung-Lim
    • Applied Chemistry for Engineering
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    • v.2 no.2
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    • pp.108-118
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    • 1991
  • Interactions between pyridine hydrodenitrogenation (HDN) and m-cresol hydrodeoxygenation(HDO), and the kinetic analysis were studied over sulfided $CoMo/{\gamma}-Al_2O_3$ catalyst at the range of temperatures between 473 K and 723 K, the total pressures between $10{\times}10^5Pa$ and $50{\times}10^5Pa$, and the contact times between 0.0125 g-cat. hr/ml-feed and 0.03g-cat. hr/ml-feed. HDN of pyridine and HDO of m-cresol were inhibited by each other and the inhibition effect of HDO by pyridine is higher than that of HDN by m-cresol. But reactivity of m-cresol is higher than that of pyridine. The rate equations of pyridine and m-cresol were given to be ${\gamma}_{HDN}=k_{HDN}{\cdot}K_pC_p/(1+K_cC_c+K_pC_p)$ and ${\gamma}_{HDO}=k_{HDO}{\cdot}K_cC_c/(1+K_cC_c+K_pC_p)$ in terms of Langmuir-Hinshellwood-Hougen-Watson model. At each temperature, reaction rate constants and adsorption equilibrium constants were determined and activation energies of pyridine HDN and m-cresol HDO are 13.83kcal/mol, respectively and the heat of adsorption are -6.458 and -5.045kcal/mol, respectively.

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(Photosensitive Polymers VII) Mechanism of Photosensitized Curing Reaction of Cinnamoylated Polymers ((感光性 高分子에 關한 硏究 VII) Cinnamoylated Polymers의 光增感 硬化反應機構)

  • Kim, Kwang-Sup;Shim, Jyong-Sup
    • Journal of the Korean Chemical Society
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    • v.10 no.4
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    • pp.166-174
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    • 1966
  • The multistep mechanism of photosensitized curing reaction cinnamoylated photosensitive polymer is proposed from the energy level diagram of cinnamic acid and sensitizer, and from the fact that excess of sensitizer brings the sensitivity to a limiting value etc. Various factors which have effects on the ability of sensitizer are also discussed. The mechanism involves following steps: activation to the first excited singlet states of cinnamoyl group(C) and sensitizer(S) by their absorption of photon, their intersystem crossing to the lowest triplet state, bimolecular internal quenching by formation of excimer of sensitizer, triplet excitation energy transfer and intermolecular addition between cinnamoyl group in ground state and that in triplet state. The rate equation derived from this mechanism is $-\frac{d[C]}{dt} = \frac{K_1[C]}{K_2 + [C]}[\frac{I^c_{abs}}{K_3 + [S]} + \frac{K_4[C]}{(K_5 + [C])(K_6 + [S])}(I^s_{abs} + \frac{K_7I^c_{abs}[S]}{K_8 + [S]})]$ where $I^c_{abs}\;and\;I^s_{abs}$: the rates of absorption of photon by cinnamoyl group and sensitizer $K_n$: Constants. It is proved with the cinnamate of poly(glyceryl phthalate)(PGC) in the absence of sensitizer using the infrared analytical method and successfully applied for the experimental data reported on the effects of the degree of cinnamoyl esterification and the concentration of sensitizer upon the sensitivity.

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Short term Efficacy of C0-C1 Mobilization in the Cervical Neutral Position in Upper Cervical Hypomobility: A Randomized Controlled Trial

  • Hidalgo-Garcia, Cesar;Tricas-Moreno, Jose Miguel;Lucha-Lopez, Orosia;Estebanezde-Miguel, Elena;Bueno-Gracia, Elena;Malo-Urries, Miguel;Perez-Guillen, Silvia;Fanlo-Mazas, Pablo;Ruiz-de-Escudero, Alazne;Krauss, John
    • Journal of International Academy of Physical Therapy Research
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    • v.7 no.1
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    • pp.908-914
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    • 2016
  • The purpose of this study is to explore the effects of mobilization of C0-C1 and C7-T1 applied to asymptomatic individuals with reduced upper cervical rotation during the FRT. Design: parallel randomized controlled trial. 48 subjects(38.52 years${\pm}15.13$) with C1-C2 rotation hypomobility in TFR joined the study and were randomized into three groups(C0, C7, control group). FRT in both directions was measured before and after the intervention. C0 intervention consisted of a dorsal translatoric mobilization of C0-C1 in the cervical neutral position. C7 intervention consisted of a ventral cranial translatoric mobilization of C7-T1 in neutral position and the control group maintained a supine position. C0 group experienced a FRT ROM to the restricted side increase of $17.64^{\circ}$(SD=4.55), that was significantly greater (P<0.001) than $5.95^{\circ}$(SD=4.81) of the C7 group and $2.45^{\circ}$(SD=5.05) of the control group. The results showed that a dorsal translatoric mobilization of C0-C1 in neutral position restored the physiological FRT mobility in subjects with C1-C2 hypomobility and experienced statistical significant improvement in FRT as compared to a C7-T1 translatoric mobilization and a control group. (Level of evidence: 1b).

SOME GEOMETRIC PROPERTY OF BANACH SPACES-PROPERTY (Ck)

  • Lee, Chongsung;Cho, Kyugeun
    • Korean Journal of Mathematics
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    • v.17 no.3
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    • pp.237-244
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    • 2009
  • In this paper, we define property ($C_k$) and show that Property ($C_k$) implies property ($C_{k+1}$). The converse does not hold. Moreover, we prove that property ($C_k$) implies the Banach-Saks property.

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Morphological Characteristics of Corylopsis Species for Landscape Uses (히어리속 식물의 조경 소재 이용을 위한 형태적 특성)

  • Shim Kyung-Ku;Ha Yoo-Mi;Lee Sun A;Park Chang Hyuk;Kim Dong Su
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.5 s.112
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    • pp.94-103
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    • 2005
  • This study was carried out to investigate growth and morphological characteristics of leaf, flower and winter bud of Corylopsis species such as C. coreana, C. spicata, C. sinensis, C. willmottiae, C. willmottiae 'Spring Purple', C. wilsonii, C. spicata 'Yellow Spring', C. gotoana, and C. vechiana. In the Corylopsis species, C. coreana, C. willmottiae, and C. vetchiana had larger flowers, longer flower cluster, and more flowers than other species. C. sinensis and C. veitchiana had fragrant flowers. In addition, species with beautiful leaf color were C. spicata 'Yellow spring' with yellow color and C. willmottiae 'Spring purple' with purple color, which eventually changed to green. The winter bud of C. sinensis, C. willmottiae, C. willmottiae 'Spring Purple', and C. vechiana were oval and different from those of other species. Comparison of the morphological characteristics among C. coreana, C. spicata, and C. sinensis, C. coreana showed they had earlier flowering dates and brighter yellow flowers than those of other species. Flower cluster of C. sinensis was shortest, but it had most number of flowers and fragrance. In addition, the winter buds of C. coreana and C. spicata with elliptical shape were different from that of C. sinensis with oval shape. Therefore, based on these characteristics, the following Corylopsis species were found to be promising as woody landscape plants: C. coreana, C. sinensis, C. willmottiae 'Spring Purple', C. spicata 'Yellow Spring', and C. vechiana.

Comparisons of Collection 5 and 6 Aqua MODIS07_L2 air and Dew Temperature Products with Ground-Based Observation Dataset (Collection 5와 Collection 6 Aqua MODIS07_L2 기온과 이슬점온도 산출물간의 비교 및 지상 관측 자료와의 비교)

  • Jang, Keunchang;Kang, Sinkyu;Hong, Suk Young
    • Korean Journal of Remote Sensing
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    • v.30 no.5
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    • pp.571-586
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    • 2014
  • Moderate Resolution Imaging Spectroradiometer (MODIS) provides air temperature (Tair) and dew point temperature (Tdew) profiles at a spatial resolution of 5 km. New Collection 6 (C006) MODIS07_L2 atmospheric profile product has been produced since 2012. The Collection 6 algorithm has several modifications from the previous Collection 5 (C005) algorithm. This study evaluated reliabilities of two alternative datasets of surface-level Tair and Tdew derived from C005 and C006 Aqua MODIS07_L2 (MYD07_L2) products using ground measured temperatures from 77 National Weather Stations (NWS). Saturated and actual vapor pressures were calculated using MYD07_L2 Tair and Tdew. The C006 Tair showed lower mean error (ME, -0.76 K) and root mean square error (RMSE, 3.34 K) than the C005 Tair (ME = -1.89 K, RMSE = 4.06 K). In contrasts, ME and RMSE of C006 Tdew were higher than those (ME = -0.39 K, RMSE = 5.65 K) of C005 product. Application of ambient lapse rate for Tair showed appreciable improvements of estimation accuracy for both of C005 and C006, though this modification slightly increased errors in C006 Tdew. The C006 products provided better estimation of vapor pressure datasets than the C005-derived vapor pressure. Our results indicate that, except for Tdew, C006 MYD07_L2 product showed better reliability for the region of South Korea than the C005 products.

Detection of Hydrocarbons to Determine Post-Irradiation of Dry Soup Base Ingredients in Instant Noodle (라면 건조 스프 재료의 방사선 조사 검지를 위한 Hydrocarbon류 검출)

  • Hwang, Keum-Taek;Park, Jun-Young
    • Korean Journal of Food Science and Technology
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    • v.30 no.5
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    • pp.1018-1023
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    • 1998
  • Hydrocarbons in dry soup base and its ingredients in instant noodle were analyzed to determine whether the analysis of hydrocarbons is a potential method to detect post-irradiation of the soup base. Soup base ingredients were irradiated individually, irradiated before mixing, or mixed after irradiation. Lipids were extracted with hexane and hydrocarbons were separated from the lipids through Florisil column. The hydrocarbons were analyzed with GC. Hydrocarbons C17:2, C16:3, C17:1, and C16:2 were detected in palm oil, red pepper powder, and sesame seeds irradiated at 10 kGy, but not in unirradiated ones. C17:2, C16:3, C17:1, and C16:2 were not detected in the soup base mixture of unirradiated ingredients. The four hydrocarbons were detected in the soup base mixture using irradiated palm oil or sesame seeds. In the mixture using irradiated red pepper powder, C17:2 and C16:3 were detected. When the soup mixture was irradiated after mixing unirradiated ingredients, C17:2, C17:1, and C16:2 were detected in the sample irradiated at 1 kGy, and C17:2, C16:3, C17:1, and C16:2 were in large amounts at 5 and 10 kGy.

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Comparison of Pepper Anthracnose Pathogens from Korea and China

  • Shin, Hyun-Joo;Chen, Zhu-Jun;Hwang, Jae-Moon;Lee, Soon-Gu
    • The Plant Pathology Journal
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    • v.15 no.6
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    • pp.323-329
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    • 1999
  • Anthracnose of pepper casued by Colletotrichum spphas been a great problems for pepper production in Korea and China. Especially Colletotrichum gloeosporioides was found predominantly over cultivation areas during infection periods and caused severe rots on bath unripe and ripe fruits that resulted in major yield losses. In this study, comparison of Colletrichum spp.isolated from Korea and China in morphology and pathgenicity, and RAPD-PCR analysis were conducted. Based on morphological characteristics, the pathogen isolates, K1 and C1, K2 and C2, and K3 and C3 were identified as Colletotrichum gloeosporioides (G) type, C. gloeosporioides (R) type and C. coccodes, respectively. in pathogenicity test, K1 and C1, and K2 and C2 were found to attack mainly fruits and to be the most virulent among isolates. K3 and C3 were strongly virulent to leaves and seedling. Pathogenicity between Korean and Chinese isolates. K3 and C3 were strongly virulent to leaves and seedling. Pathogenicity between Korean and Chinese isolates did not show any difference. Results of the RAPD-PCR analyses indicate the varying levels of molecular diversity within and between Colletotrichum spp.of Korea and China. The similarities between K1 and C1, K2 and C2, and K3 and C3 were 85.71%, 71.43% and 50.0% respectively.

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