• Title/Summary/Keyword: 합성 작용

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Selectivity Changes in CO Hydrogenation over Potassium Added Titania-supported Cobalt Catalysts (티타니아 담지 코발트 촉매를 이용한 일산화탄소 수소화 반응에서 칼륨첨가에 의한 선택성 변화)

  • Lee, Dong-Keun;Ahn, Jou-Hyeon
    • Applied Chemistry for Engineering
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    • v.1 no.1
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    • pp.100-105
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    • 1990
  • Small amounts of potassium were added to the titania - supported cobalt catalysts in order to produce higher and olefinic hydrocarbons in CO hydrogenation. Titania and potassium played important roles not only for the enhancement of the production of higher and olefinic hydrocarbons, but also for the prevention of the catalyst deactivation by carbon deposits. Titania support induced the so - called SMSI, and potassium seemed to act as an electronic modifier, giving rise to an electron enrichment of the metallic phase.

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The Anti -allergic Effects of Taraxaci Herba(蒲公英) on the RBL-2H3 Cells (RBL-2H3 세포에서 포공영의 항알레르기 효과)

  • Jo, Ju-Heum;Lyu, Ji-Hyo;Kim, Cheol-Hong;Kang, Kyung-Hwa;Yoon, Hwa-Jung;Lee, Seung-Yeon;Ko, Woo-Shin;Kim, Won-Il
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.20 no.1 s.32
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    • pp.209-217
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    • 2007
  • 청열해독(淸熱解毒) 작용을 하는 포공영의 항알러지 효과를 알아보기 위하여 RBL-2H3 cell line에 PMA와 A23187을 자극한 후 RBL-2H3 cell내 과립의 degranulation의 억제정도를 살펴보기 위하여 ${\beta}-Hexosaminidase$의 누출량의 억제 정도를 살펴본 결과 포공영은 농도 의존적으로 현저하게 degranulation을 억제하였다. 알러지 반응 시 세포내에서 분비되어 중요한 작용을 하는 것으로 알려진 사이토카인인 $TNF-{\alpha}$, IL-4의 합성조절 정+도를 살펴본 결과, $TNF-{\alpha}$, IL-4의 mRNA 수준에서의 발현의 조절을 통한 합성도 억제하였다. 이 결과로 보아 포공영은 알레르기와 관련된 질환에 치료약물로서 응용이 가능할 것으로 사료된다.

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Optimization of Synthesis Process for Zeolite 4A Using Statistical Experimental Design (통계적 실험계획법을 이용한 제올라이트 4A 합성 최적화)

  • Yun, Mi Hee;Yoo, Kye Sang
    • Applied Chemistry for Engineering
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    • v.28 no.3
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    • pp.286-289
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    • 2017
  • Synthesis of zeolite 4A was carried out to optimize the nanoparticle synthesis process using statistical experimental design method. The zeolite 4A was synthesized by controlling the concentration of the silicon precursor, sodium metasilicate (SMS), and characterized by XRD, SEM and nitrogen adsorption. In particular, the property of zeolite 4A can be determined by XRD analysis. Using the general factor analysis in the design of experiments, we analyzed main effects and interactions according to the reactor, reaction temperature and reaction time. The optimum reaction condition for the synthesis of zeolite 4A crystallinity was using an autoclave for 3 hours at $110^{\circ}C$. Furthermore, the optimal synthesis conditions of zeolite 4A with various crystallinity using Ludox as a silicon precursor were presented of what using both the surface and contour plot.

Flexural Capacity of the Encased(Slim Floor) Composite Beams with Web Openings -Deep Deck Plate and Asymmetric Steel Beam to be Welded Cover Plate- (매립형 (슬림플로어) 유공 합성보의 휨성능 평가 -춤이 깊은 데크플레이트와 비대칭 H형강 철골보-)

  • Kwak, Myong Keun;Heo, Byung Wook;Bae, Kyu Woong
    • Journal of Korean Society of Steel Construction
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    • v.16 no.5 s.72
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    • pp.575-586
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    • 2004
  • This paper presents an experimental study on the flexural capacity of an encased(slim-floor) composite beam, which is a wider plate under bottom flange of H-beam with web openings. Five simple full-scale bending tests were conducted on the encased(slim-floor) composite beams at varying steel beam heights (250mm and 300mm), positions of web openings, and loading conditions. The test results revealed that the web-open encased composite beam had sufficient composite action, without any additional shear connection devices, because of the inherent shear-bond effects between the steel beam and the concrete, and a stable structural performance without web-opening reinforcements.

The Synthesis of Kyotorphin Derivative by $\alpha$-Chymotrypsin ($\alpha$-Chymotrypsin 을 이용한 Kyotorphin 유도체의 합성)

  • Jeon, Yu Jin;Kim, Se Gwon
    • Journal of the Korean Chemical Society
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    • v.38 no.6
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    • pp.449-455
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    • 1994
  • In order to obtain the basic data for synthetic studies of bioactive peptide using enzyme, Kyotorphin(analgesic peptide) derivative was synthesized from Ac-Tyr-OH and $Arg-NH_2$ by $\alpha-chymotrysin$ in two phase system(organic phase and aqueous phase). In effect of organic solvent on Kyotorphin derivative synthesis from Ac-Tyr-OH(10 mM) and $Arg-NH_2$ (20 mM), the synthesis in ethyl acetate system of organic solvents was higher than those in other organic solvents (n-butanol, n-hexane, dichloromethane and chloroform). The optimal conditions for the synthesis are as follows: enzyme conc., 10 ${\mu}M;$ reaction pH, 7.0; reaction temp., $35^{\circ}C$ ; the ratio of organic phase volume/aqueous phase volume $(\alpha)$, 15. Under the optimal conditions, the yield was 70.2%, and the reaction achieved to equilibrium after 24 hrs.

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Enhancement of Glucose-Fueled Cell-Free Protein Synthesis by the Addition of Lipids (지질의 첨가를 통한 포도당 기반 무세포 단백질 합성 시스템의 단백질 발현 효율 향상)

  • Lee, So Jeong;Kim, Ho-Cheol;Kim, Dong-Myung
    • Korean Chemical Engineering Research
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    • v.57 no.1
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    • pp.85-89
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    • 2019
  • Cell-free protein synthesis utilizes the translational machinery in a cell extract. Unlike the conventional cell-based expression methods, not being affected by the conditions for cell growth, cell-free protein synthesis enables flexible manipulation of individual factors affecting the efficiency protein biosynthesis. However, the high cost and low stability of the energy sources to regenerate ATP have limited the use of cell-free synthesis for large-scale production of recombinant proteins. One of the approaches to address this problem is to use glucose as an alternative energy source to regenerate ATP through the glucose-metabolizing pathways in a cell extract. In this study, in an attempt to improve the efficiency of ATP regeneration by reinforcing oxidative phosphorylation process, we supplemented with cellular lipids to a glucose-fueled reaction mixture for cell-free protein synthesis. As a result of the lipid supplementation, the productivity of chloramphenicol acetyltransferase in a cell-free synthesis system using glucose increased more than 6 fold compared to when the lipid was not supplemented.

A Study on the Composite Behavior of Simply Supported Composite Girders Considering the Partial Interaction (불완전 합성율을 고려한 단순합성형의 합성거동에 관한 연구)

  • Yong, Hwan Sun;Kim, Seok Tae;Park, Jae Yil
    • Journal of Korean Society of Steel Construction
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    • v.9 no.4 s.33
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    • pp.543-555
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    • 1997
  • Generally, in a steel-concrete composite gilder, the shear connector which was constructed between concrete deck and steel girder should have enough stiffness to behave as one body, because the conformity between plate and concrete deck is influences by the stiffness and spacing of the shear connectors. If the stiffness of shear connectors are insufficient, slip would happen at the contact surface. Partial interaction is the case that takes account of slips. In this paper, an easy method is presented to evaluate the stiffness or spacing of the shear connector according to the degree of imperfection without difficult calculations for a composite gilder with partial interaction. Also, the horizontal shearing force applied to the shear connector and the longitudinal axial force, which is occurs at contact surface between concrete deck and steel girder, have been presented in a simple influence line that is various to the parameters of sectional properties, degree of imperfection and applied load points. Furthermore, through the case study, it determined the relationships between the degree of imperfection and the follows 1) spring constants 2) axial force and horizontal shearing force 3) stress and neutral axis by using the partial differential equation based on Newmark's Partial Interaction Theory.

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Characterization of Synthetic Na-beidellite (합성 Na-베이델라이트의 광물특성)

  • Ryu Gyoung-Won;Chae Soo-Chun;Bae In-Kook;Choi Sang-Hoon;Jang Young-Nam
    • Journal of the Mineralogical Society of Korea
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    • v.18 no.2
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    • pp.109-115
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    • 2005
  • Beidellite, a member of the smectite group, was synthesized hydrothermally from dickite. Physical and chemical properties of the synthetic Na-beidellite were characterized by the analytical methods of XRD, IR, TG, DTA, EDS, XRF and ICP. The result of Greene-Kelly test indicates that the synthesized smectite is Na-beidellite. IR spectrum of synthesized beidellite exhibited Al-O-H bending vibration at $818\;cm^{-1}\;and\;770\;cm^{-1}$ which was observed particularly in pure beidellite. TGA analysis revealed that the synthesized Na-beidellite comprises $16\;wt\%$ of water. DTA curve showed an endothermic peak at $117^{\circ}C$ due to dehydration reaction and peaks at $482^{\circ}C$ and $685^{\circ}C$ due to dehydroxylation reaction. The clay mineral was transformed to mullite and cristobalite at the temperature of $1028^{\circ}C$. The CEC value, Methylene Blue test and swelling capacity was determined to be $116\~118\;cmol/kg,\;84\~91\%,\;29\~32\;mL/2g$, respectively. The chemical composition of the synthesized phase was identified as $Na_{0.5}Al_{2.5}Si_{3.5}O_{10}(OH)_2$ from EDS and XRF analyses.

Inhibitory Efficacy of Black Tea Water Extract on Melanogenesis in Melan-a Cells and Its Action Mechanisms (멜라닌 세포에서 홍차 열수추출물의 멜라닌 합성 저해능과 작용기전)

  • Choi, So-Young;Kim, Young-Chul;Chang, Byung-Soo
    • Applied Microscopy
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    • v.41 no.3
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    • pp.169-177
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    • 2011
  • To evaluate the whitening effect of Camellia sinensis water extract (CSWE), CSWE was treated to melan-a cells. Total polyphenol contents and flavonoid contents of CSWE were 102 mg/g and 87 mg/g, respectively. The electron-donating ability of CSWE revealed a dose-dependent response, showing the excellent ability of 82% at 800 ${\mu}g$/mL, and which was higher than the arbutin (48%). The CSWE significantly (p<0.001) suppressed the melanin synthesis and the development of melanocyte dendrites was inhibited in a dose-dependent manner. The CSWE significantly (p<0.001) inhibited both intra-cellular and cell-extracted tyrosinase activities. And inhibitory efficacies of CSWE on both melanin synthesis and tyrosinase activity were significantly (p<0.001) higher than the arbutin. The tyrosinase protein expression was not influenced by arbutin treatment. However, CSWE treatment significantly (p<0.001) reduced it. Both arbutin and CSWE treatment did not influence on mRNA expressions of tyrosinase, tyrosinase-related protein-1 and tyrosinase related protein-2.

Knowledge based Text to Facial Sequence Image System for Interaction of Lecturer and Learner in Cyber Universities (가상대학에서 교수자와 학습자간 상호작용을 위한 지식기반형 문자-얼굴동영상 변환 시스템)

  • Kim, Hyoung-Geun;Park, Chul-Ha
    • The KIPS Transactions:PartB
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    • v.15B no.3
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    • pp.179-188
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    • 2008
  • In this paper, knowledge based text to facial sequence image system for interaction of lecturer and learner in cyber universities is studied. The system is defined by the synthesis of facial sequence image which is synchronized the lip according to the text information based on grammatical characteristic of hangul. For the implementation of the system, the transformation method that the text information is transformed into the phoneme code, the deformation rules of mouse shape which can be changed according to the code of phonemes, and the synthesis method of facial sequence image by using deformation rules of mouse shape are proposed. In the proposed method, all syllables of hangul are represented 10 principal mouse shape and 78 compound mouse shape according to the pronunciation characteristics of the basic consonants and vowels, and the characteristics of the articulation rules, respectively. To synthesize the real time facial sequence image able to realize the PC, the 88 mouth shape stored data base are used without the synthesis of mouse shape in each frame. To verify the validity of the proposed method the various synthesis of facial sequence image transformed from the text information is accomplished, and the system that can be applied the PC is implemented using the proposed method.