• Title/Summary/Keyword: Reaction zone

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Diagnosis and Treatment of Connective Tissue Massage (결합조직마사지의 진단과 치료)

  • Bae Sung-soo;Choi Jae-won;Lee Keun-heui;Kim Jong-soon;Kim Soo-min;Kim Byung-jo;Hwang Bo-Gak;Ju Mu-yeol
    • The Journal of Korean Physical Therapy
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    • v.14 no.4
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    • pp.224-233
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    • 2002
  • General massage and sports massage techniques are kneading, petrisage and tappotment. These will be improve physiological reaction. Connective tissue massage is a reflex zone massage in the subcutaneous tissues. These are superficial and deeper fascia, intermuscular septa, blood vessel, perinerve tissue. It is frame work on organs in human-being, Therefore, abnormality of there tissues are a pathologic change of the organs. The pathologic changes are fined with visible investigation, manual investigation and stroking investigation on the reflex zone. The stroking on the reflex zone is the treatment also. Stroking methods are depend upon tissues and area. Short strokings are directed at approximately right angles against bone, muscular or facial board. Long strokings are very often follow the original cleavage lines. The back is divided for treatment purposes into sections. There are basic section, thoracic section and cervical section.

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Effects of Shock Waves on the Mixing and the Recirculation Zone of Supersonic Diffusion Flames (초음속 확산화염 내의 혼합과 재순환 영역에 대한 충격파의 영향)

  • Kim, Ji-Ho;Huh, Hwan-Il;Choi, Jeong-Yeol;Yoon, Young-Bin;Jeung, In-Seuck
    • 한국연소학회:학술대회논문집
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    • 1998.10a
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    • pp.123-129
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    • 1998
  • A numerical study has been conducted to investigate the effect of shock waves on the mixing and the recirculation zone of a hydrogen jet diffusion flame in a supersonic combustor. The general trends are compared with the experimental results obtained from the supersonic combustor at the University of Michigan. For the numerical simulation of supersonic diffusion flames, multi-species Navier-Stokes equations and detailed chemistry reaction equations of $H_2$-Air are considered. The $K-{\omega}/k-{\varepsilon}$ blended two equation turbulent model is used. Roe's FDS method and MUSCL method are used for convection fluxes in governing equations. Numerical results show that when slender wedges are mounted at the combustor wall the mixing and the combustion are enhanced and the size of recirculation zone is increased . The flame shape of supersonic flames is different in the flame-tip; it is not closed but open. The flame shape is shown to be greatly affected by shock waves.

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Analysis on the Scales formed on the Heat Affected Zone of Low Carbon Steel Weld in NaCl and H2S Water Solutions (저탄소강 용접열영향부의 NaCl, H2S 수용액에서 생성되는 부식스케일 분석)

  • Kim, Min-Jung;Bae, Dong-Ho;Lee, Dong-Bok
    • Journal of Surface Science and Engineering
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    • v.43 no.4
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    • pp.205-210
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    • 2010
  • The A106 Gr B low carbon steel, which was used in the electric power plants and heavy chemical plants, was welded by multi-pass arc welding. The heat affected zone (HAZ) formed by welding was corroded in acid chloride solution, or in saturated $H_2S$ containing acid chloride solution, or in saturated $H_2S$ containing acid chloride solution under applied current. In this order of corrosion solution, the rate of corrosion increased, because $H_2S$ accelerated the iron dissolution, hydrogen evolution, and the formation of nonprotective FeS, whereas the applied current accelerated the electrochemical reaction. The scales formed in acid chloride solution consisted primarily of $Fe_3O_4$, while those formed in $H_2S$ containing acid chloride solution consisted primarily of $Fe_3O_4$ and FeS.

A new merging-zone flow injection system for the quantification of ferrous and ferric ions in aqueous solution and sludge of wastewater

  • Farhood, Ahmed Saleh;Taha, Dakhil Nassir
    • Analytical Science and Technology
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    • v.35 no.5
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    • pp.218-227
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    • 2022
  • A simple and fast throughput flow injection (FI) system with a merging-zone technique was designed to determine ferrous and ferric in an aqueous solution. The method is based on the direct reaction of ferrous with a Bathophenanthroline reagent (Bphen) in acidic media. The forming red complex absorbs light at 533 nm. All conditions of the flow injection system were investigated. The analytical curve of ferrous was linear in the range of 0.07 to 4 mg/L with an r2 value of 0.9968. The detection and quantification limits were 0.02 and 0.04 mg/L, respectively. The molar absorptivity and Sandell's sensitivity were 4.0577 × 106 L/mol cm and 25 × 10-5 ㎍/cm2, respectively. The homemade valve was low-cost with high repeatability (n = 7) at an RSD of 1.26 % and zero dead volume. The values of the dispersion coefficient were 2.318, 2.022, and 1.636 for the concentrations of 0.2, 1, and 3 mg/L, respectively. The analysis throughput of the designed flow injection unit was 57 sample per hour.

Research and Optimization of Four Serpentine-Wave Flow Fields in PEMFC

  • Fayi Yan;He Lu;Jian Yao;Xuejian Pei;Xiang Fan
    • Journal of Electrochemical Science and Technology
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    • v.15 no.3
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    • pp.373-387
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    • 2024
  • The layout of the cathode flow field largely determines the net output power of the proton exchange membrane fuel cell (PEMFC). To make the normal mass transfer effect best, the longitudinal channel was waved based on four serpentine flow channels, and the effects of sag depth and longitudinal channel width on the output efficiency of the cell were explored. The results show that the wave channel design systematically enhances the forced convection between adjacent channels, which can prevent a large zone of oxygen starvation zone at the outlet of the channel. The increase of the normal velocity in the gas transmission process will inevitably induce a significant enhancement of the mass transfer effect and obtain a higher current density in the reaction zone. For the longitudinal channel width, it is found that increasing its size in the effective range can greatly reduce the channel pressure drop without reducing the output power, thereby improving the overall efficiency. When the sag depth and longitudinal channel width gradient are 0.6 mm and 0.2 mm respectively, PEMFC can obtain the best comprehensive performance.

Studies on Application of Starch Part I. Action of Amylase on Starch Agar-gel-plate (전분이용(澱粉利用)에 관한 연구(硏究)(제(第) 1 보(報)) Starch Agar-gel-plate를 이용(利用)한 Amylase 활성(活性) 측정법(測定法))

  • Yu, Ju-Hyun;Chu, Kyung-Hee;Hong, Yun-Myung;Arima, K.
    • Korean Journal of Food Science and Technology
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    • v.2 no.1
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    • pp.67-71
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    • 1970
  • The amylase was0 incubated in a 9mm hole on the starch agar gel plate bored with a cork borer. When 0.1N-iodine solution sprayed on the plate, the formed uncolored zone were observed. An activity of amylase has been determined by measurement of diameter of the uncolored zone. We named this method 'cork borer method'. When amylase was incubated on the starch agar gel plate, the following points were obtained. 1) The optimum pH for the formation of the zone in case of amylases(Biotex, Spitase) which produced by Bacillus is neutrality and alkali, while that for Glucoamylase, Biodiase, and Mucorrennin which produced by Rhizopus and Mucor is from 5 to 7. 2) The diameter of the zone was increased by the incubation time and amylase activity. 3) The zone was easily formed at low level of starch concentration and was formed much bigger than at $50^{\circ}C\;than\;at\;10^{\circ}C$. From the above results, after malting the starch agar gel plate, keeping constant concentration of the starch, the measurement of amylase activity is in efficiency upon the constant reaction time and temperature.

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Design of a Model Reference Adaptive Control System with Dead Zone

  • Yokota, Yukihiro;Uchiyama, Kenji;Shimada, Yuzo
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1239-1244
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    • 2004
  • Precise positioning is an important problem facing motion control systems which usually use electric motor. A motor possesses a nonlinear property which degrades the positioning accuracy. Therefore, a compensator which linearizes the relationship between the angular velocity and input signal of the motor is required to enable precise positioning. In this paper, the design of a Model Reference Adaptive Control System (MRACS) for realizing the precise positioning for a system using a motor including the nonlinear property is described. The designed MRACS is applied to the attitude control problem on a satellite using a DC servomotor to drive its reaction wheel. Experimental results demonstrate the validity of a proposed control method for a positioning control system with an electric motor.

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An Investigation about Dynamic Behavior of Three Point Bending Specimen

  • Cho, Jae-Ung;Han, Moon-Sik
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.4
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    • pp.149-157
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    • 2000
  • Computer simulations of the mechanical behavior of a three point bend specimen with a quarter notch under impact load are performed. The case with a load application point at the side is considered. An elastic-plastic von Mises material model is chosen. Three phases such as impact bouncing and bending phases are found to be identified during the period from the moment of impact to the estimated time for crack initiation. It is clearly shown that no plastic deformation near the crack tip is appeared at the impact phase. However it is confirmed that the plastic zone near the crack tip emerges in the second phase and the plastic hinge has been formed in the third phase. Gap opening displacement crack tip opening displacement and strain rate are compared with rate dependent material(visco-plastic material). The stability during various dynamic load can be seen by using the simulation of this study.

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A Study on Measurement of NO Concentrations in Laminar Premxied $CH_4/O_2/N_2$ Flames by LIF (레이저 유도 형광법(LIF)을 이용한 층류 메탄 예혼합 화염내 NO 농도측정에 관한 연구)

  • Kim, Sun-Wook;Jin, Seong-Ho;Kim, Gyung-Soo;Park, Kyoung-Suk
    • Proceedings of the KSME Conference
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    • 2000.11b
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    • pp.156-161
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    • 2000
  • In this study, quantitative nitric oxide concentration distributions are investigated in the post-flame zone of laminar premixed $CH_4/O_2/N_2$, flames by laser-induced fluorescence (LIF). The measurements are taken in flames for different equivalence ratios varying from $0.8{\sim}1.4$, and flow rate is fixed as 5slpm. The NO A-X (0,0) vibrational band around 226 nm is excited using a XeCl excimer-pumped dye laser. Selecting an appropriate NO transition minimizes interferences from Rayleigh scattering and $O_2$ fluorescence. NO concentration is rised when equivalence ratios increase at different vertical distances form nozzle tip. In any case, the maximum NO concentration reaches the maximum in reaction zone.

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A Study on the Effect of the $CO_2$ Gas on the Growth Mechanism of the Nitrocarburized Layer (연질화층의 성장기구에 미치는 $CO_2$가스의 영향에 관한 연구)

  • Lee, Gu-Hyeon
    • 연구논문집
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    • s.25
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    • pp.175-184
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    • 1995
  • Mechanical properties of the gas nitrocarburized product depend on the surface compound layer and the diffusion zone formed. The compound layer improves the wear resistance, and the corrosion resistance. Though phase composition, pore layer and growth rate of the compound layer varies according to the treatment time, temperature and the kind of the steel substrate, they are strongly influenced by the environmental gas composition. In the current study, the growth behavior of the compound layer and diffusion zone of the carbon steel and the alloy steel upon nitrocarburizing treatment at $570^{\circ}C$, and the phase composition and the variation in the growth rate of the compound layer according to the variation of the gas environment which was the medium of the nitriding and carburizing reaction were investigated.

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