• 제목/요약/키워드: Sequential Reaction

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Sequential pattern load modeling and warning-system plan in modular falsework

  • Peng, Jui-Lin;Wu, Cheng-Lung;Chan, Siu-Lai
    • Structural Engineering and Mechanics
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    • 제16권4호
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    • pp.441-468
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    • 2003
  • This paper investigates the structural behavior of modular falsework system under sequential pattern loads. Based on the studies of 25 construction sites, the pattern load sequence modeling is defined as models R (rectangle), L and U. The study focuses on the system critical loads, regions of largest reaction forces, discrepancy between the pattern load and the uniform load, and the warning-system plan. The analysis results show that the critical loads of modular falsework systems with sequential pattern loads are very close to those with the uniform load used in design. The regions of largest reaction forces are smaller than those calculated by the uniform load. However, the regions of largest reaction forces of three models under sequential pattern loads can be considered as the crucial positions of warning-system based on the measured index of loading. The positions of the sensors for the warning-system for these three different models are not identical.

Development and Applications of a Chemical Method for Sequential Analysis of Reducing Oligosaccharides

  • Hong, Seon-Pyo;Lee, Yong-Moon;Hiroshi-Nakamura
    • Archives of Pharmacal Research
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    • 제20권2호
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    • pp.184-190
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    • 1997
  • A new method based on the chemical reaction has been devised for the sequential analysis of reducing oligosaccharides using 8-amino-2-naphthalenesulfonic acid (ANS), a fluorescent precolumn derivatization reagent for reducing saccharides. The procedure established includes 1) the derivatization of a reducing oligosaccharide to produce a Schiff base, 2) the reduction of the base with sodium cyanoborohydride $(NaBH_3/CN), 3)$ the methoxycarbonylation of the resultant secondary amino group, 4) the cleavage of the glycoside bond next to the reducing end, based on the intramolecular acid hydrolysis by the action of a sulfonic acid group of the ANS derivative, 5) the identification of the liberated reducing end by high-performance liquid chromatography (HPLC), and finally 6) the recovery of the resultant oligosaccharide fragment from the cleavage reaction mixture. The extensive examination of the conditions for the sequential analysis of reducing oligosaccharides resulted in the procedure of simplicity , high selectivity and high recovery. This procedure was found to be useful for the sequential analysis of di-, tri- and tetrasaccharides.

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순차식 촉매연소 시스템 (Sequential Catalytic Combustion System)

  • 유상필;송광섭;류인수;정남조
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
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    • pp.153-158
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    • 2003
  • Catalytic Combustion used to be applied to specific conditions because of the characteristics different from flame combustion. However, many researches are focused on widening the applicant range of catalytic combustion with the competences of catalytic combustion. The development of many catalytic combustion appliances is one of the trials to overcome the restrictions of reaction and maximize the merits. In this research, past developments of appliances are depicted and new conceptual system will be introduced - sequential system. Sequential catalytic combustion system is composed of units - existing catalytic heat exchangers. This system is performed with parallel in composition and serially in operation. First, the burden of the preheating can be dramatically reduced. Second, stable operation control is expected. Lastly, Capacity expansion is flexible.

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Comparison of Motor Skill Acquisition according to Types of Sensory-Stimuli Cue in Serial Reaction Time Task

  • Kwon, Yong Hyun;Lee, Myoung Hee
    • The Journal of Korean Physical Therapy
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    • 제26권3호
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    • pp.191-195
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    • 2014
  • Purpose: The purpose of this study is to investigate whether types of sensory-stimuli cues in terms of visual, auditory, and visuoauditory cues can be affected to motor sequential learning in healthy adults, using serial reaction time task. Methods: Twenty four healthy subjects participated in this study, who were randomly allocated into three groups, in terms of visual-stimuli (VS) group, auditory-stimuli (AS) group, and visuoauditory-stimuli (VAS) group. In SRT task, eight Arabic numbers were adopted as presentational stimulus, which were composed of three different types of presentational modules, in terms of visual, auditory, and visuoauditory stimuli. On an experiment, all subjects performed total 3 sessions relevant to each stimulus module with a pause of 10 minutes for training and pre-/post-tests. At the pre- and post-tests, reaction time and accuracy were calculated. Results: In reaction time, significant differences were founded in terms of between-subjects, within-subjects, and interaction effect for group ${\times}$ repeated factor. In accuracy, no significant differences were observed in between-group and interaction effect for groups ${\times}$ repeated factor. However, a significant main effect of within-subjects was observed. In addition, a significant difference was showed in comparison of differences of changes between the pre- and post-test only in the reaction time among three groups. Conclusion: This study suggest that short-term sequential motor training on one day induced behavioral modification, such as speed and accuracy of motor response. In addition, we found that motor training using visual-stimuli cue showed better effect of motor skill acquisition, compared to auditory and visuoauditory-stimuli cues.

Sequential Polyadenylation to Enable Alternative mRNA 3' End Formation

  • Yajing Hao;Ting Cai;Chang Liu;Xuan Zhang;Xiang-Dong Fu
    • Molecules and Cells
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    • 제46권1호
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    • pp.57-64
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    • 2023
  • In eukaryotic cells, a key RNA processing step to generate mature mRNA is the coupled reaction for cleavage and polyadenylation (CPA) at the 3' end of individual transcripts. Many transcripts are alternatively polyadenylated (APA) to produce mRNAs with different 3' ends that may either alter protein coding sequence (CDS-APA) or create different lengths of 3'UTR (tandem-APA). As the CPA reaction is intimately associated with transcriptional termination, it has been widely assumed that APA is regulated cotranscriptionally. Isoforms terminated at different regions may have distinct RNA stability under different conditions, thus altering the ratio of APA isoforms. Such differential impacts on different isoforms have been considered as post-transcriptional APA, but strictly speaking, this can only be considered "apparent" APA, as the choice is not made during the CPA reaction. Interestingly, a recent study reveals sequential APA as a new mechanism for post-transcriptional APA. This minireview will focus on this new mechanism to provide insights into various documented regulatory paradigms.

위성자세 최소시간 거동을 위한 추력기와 반작용 휠 통합제어 (Hybrid Control with Thrusters and Reaction Wheels for Time Optimal Attitude Maneuvers of Spacecraft)

  • 이병훈;이봉운;오화석;이선호;이승우
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.1578-1583
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    • 2003
  • Time-Optimal solutions for attitude control with reaction wheels as well as with thrusters are studied. The suggested varying-time-sharing ratio thrusting is found to reduce the maneuvering time enormously. The hybrid control such as sequential hybrid and simultaneous hybrid with reaction wheels and thrusters are considered. The results show that simultaneous hybrid method reduces the maneuver time very much. Spacecraft model is KOrea Multi-Purpose SATellite(KOMPSAT)-II, which is being developed by KARI in KOREA as an agile maneuvering satellite.

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Epitaxial Growth of Polyurea Film by Molecular Layer Deposition

  • 최성은;강은지;이진석
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.264.2-264.2
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    • 2013
  • Molecular layer deposition (MLD) is sequential, self-limiting surface reaction to form conformal and ultrathin polymer film. This technique generally uses bifunctional precursors for stepwise sequential surface reaction and entirely organic polymer films. Also, in comparison with solution-based technique, because MLD is vapor-phase deposition based on ALD, it allows epitaxial growth of molecular layer on substrate and is especially good for surface reaction or coating of nanostructure such as nanopore, nanochannel, nanwire array and so on. In this study, polyurea film that consisted of phenylenediisocyanate and phenylenediamine was formed by MLD technique. In situ Fourier Transform Infrared (FTIR) measurement on high surface area SiO2 substrate was used to monitor the growth of polyurethane and polyurea film. Also, to investigate orientation of chemical bonding formed polymer film, plan-polarized grazing angle FTIR spectroscopy was used and it showed epitaxial growth and uniform orientation of chemical bones of polyurea films.

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The First Synthesis of Dually Modified Southern-Mimicking Nucleoside: 4'-Methyl Branched and Bicyclo [3.1.0] Hexane Locked Nucleoside

  • Kim, Kwan-Woo;Hong, Joon-Hee
    • Bulletin of the Korean Chemical Society
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    • 제25권5호
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    • pp.668-672
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    • 2004
  • This paper reports the stereoselective synthesis of a novel nucleoside, 4'-methyl branched and bicyclo [3.1.0] hexane locked-nucleoside 12, using a sequential [3,3]-sigmatropic rearrangement/carbene cycloaddition reaction/Curtius reaction strategy with a high stereoselectivity.

순차식 촉매연소 시스템 (Sequential Catalytic Combustion System)

  • 유상필;정남조;이승재;류인수;강성규;송광섭
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 2004년도 춘계 학술발표회 논문집
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    • pp.197-200
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    • 2004
  • Compared to conventional flame combustion, catalytic combustion had the advantage of oxidation of V.O.C. gas which was high voluminous, low caloric mixture flow. However, the temperature of mixture gas should be over the one of catalytic reaction start and the control of reaction on the catalytic surface tends to be vulnerable. To overcome these obstacles, composition of both catalytic combustor and heat exchanger was devised and named the sequential catalytic combustion system. In this system, only trigger unit needed preheating process for transient starting time. Once trigger unit was ignited, the next unit w3s supplied heat to ignite from that and same process was performed to the last one sequentially. When it come to steady state, whole mixture gas was oxidated at each unit simultaneously and preheating for trigger unit was not needed any more. System of 100 kcalh/hr capacity was devised and operated successfully.

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