• Title/Summary/Keyword: Reaction zone

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The Effects of Acupuncture at Sobu (HT8) and Haenggan (LR2) on Scopolamine-induced Cognitive Impairment in Rat Model

  • Song, Ho-Joon;Cho, Myoung-Rae
    • Journal of Acupuncture Research
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    • v.35 no.1
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    • pp.28-36
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    • 2018
  • Background: This study investigated the effects of acupuncture at Sobu (HT8) and Haenggan (LR2) on scopolamine-induced, cognitively impaired rats. Methods: Scopolamine-treated Sprague-Dawley rats were divided into 6 groups; normal, control, HT8, LR2, HT8 + LR2 and sham group. Cognitive impairment was induced by scopolamine, in control, and then in HT8, LR2, HT8 + LR2 and sham groups. Acupuncture treatment was performed at HT8, LR2, HT8 + LR2, and a random acupoint, respectively, every other day for 2 weeks. After each treatment, behavior change was observed and the rats were sacrificed. The change in brain-derived neurotrophic factor, glutathione peroxidase, and superoxide dismutase activity was evaluated by polymerase chain reaction. Results: Latency time to target in Morris Water-Maze test for the HT8 + LR2 group showed a significant decrease compared with control (p<0.05). Target crossing times and time zone ratios in Morris Water-Maze test for HT8 + LR2 group showed a significant increase compared with control (p<0.01). In the Y-Maze test the HT8 + LR2 group showed a significant increase compared with control (p<0.05). Brain-derived neurotrophic factor, glutathione peroxidase, and superoxide dismutase, in the HT8 + LR2 group, showed a significantly increased level compared with control (p<0.05). Neural activity of acetylcholine esterase in HT8 + LR2 group showed a significant decrease compared with the control group (p<0.01), choline acetyltransferase activity in the HT8 + LR2 group showed a significant increase compared with control (p<0.05). Conclusion: Acupuncture at HT8 + LR2 restored scopolamine-induced cognitive impairment, suggesting acupuncture could be an alternative to improve cognitive function.

Effect of AC Electric Fields on Counterflow Diffusion Flame of Methane (메탄의 대향류 확산화염에 대한 AC 전기장의 영향)

  • Choi, Byung-Chul;Kim, Hyung-Kuk;Chung, Suk-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.8
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    • pp.849-855
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    • 2012
  • The effect of electric fields on the response of diffusion flames in a counterflow has been investigated experimentally by varying the AC voltage and frequency. The result showed that the flame was stationary with high AC frequency above the threshold frequency, and it increased with the applied voltage and then leveled off at 35 Hz. Below the threshold frequency, however, the flame oscillated with a frequency that was synchronized with the applied AC frequency. This oscillation can be attributed to the ionic wind effect due to the generation of bulk flow, which arises from the momentum transfer by molecular collisions between neutral molecules and ions, where the ions in the reaction zone were accelerated by the Lorentz force.

Improvement of the $SO_{x}$ Removal by Adding Dibasic Acids into the JBR FGD Process

  • Lee, Byeong-Kyu;Jeon, Sang-Ki;Cho, Seong-Won
    • Journal of Korean Society for Atmospheric Environment
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    • v.17 no.E4
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    • pp.157-162
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    • 2001
  • Jet Bubbling Reactors(JBRs) were operated for the removal of SO$_{x}$ in flue gases produced from many electric power plants. However, many JBR flue gas desulfurization (FGD) facility faced a decrease of SO$_{x}$ removal efficiency and an increase of scale problems with continuous operations. We increased alkalinity of the SO$_{2}$ absorbing medium by adding the dibasic acids (DBAs) to solve these problems more effectively. The SO$_{2}$ removal efficiency, the purity of CaCO$_{3}$ and COD of the wastewater was measured to identify the addition effects of DBAs (150, 200, 250, and 400 ppm) for 2hr in a day into the JBR attached to the large-scale power plants (400 MW$\times$3). Addition of the DBAs resulted in the improvement of the SO$_{2}$ removal efficiency from 2 to 5% and the purity of the gypsum from 1 to 2%; these improvement were due to the alkalinity increase of the absorbing medium and the reduction of a proportion of un-reacted CaCO$_{3}$, respectively. Also, the scale problems formed by un-reacted CaCO$_{3}$ inside the reaction zone of the JBR were substantially reduced. Even though the effluent COD of the wastewater slightly increased from 10~15 to 18~36 mg/l and the erosion problems in the injection pump and duct occurred, this method of increasing SO$_{2}$ removal efficiency by adding the DBAs could be considered as a profitable approach.ach.

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Fatigue Crack Growth Behavior of a Magnesium-Based Composite (마그네슘 금속복합재의 피로균열거동해석)

  • Kim, Doo Hwan;Park, Yong Gul;Kim, Sung Hoon;Han, Suk Kyu
    • Journal of Korean Society of Steel Construction
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    • v.9 no.4 s.33
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    • pp.515-521
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    • 1997
  • The effects of heat treatment and fiber orientation on tensile strength and fatigue behavior were studied in a continuously reinforced. magnesium-based composite Following an earlier TEM investigation, specimens were thermally aged to modified the interfacial zone between the alumina fibers and the magnesium alloy matrix. From the tensile experimental results, the ultimate tensile strength of the aged specimens were lower than that of the as-fabricated due to weak fiber-matrix interfacial strength with chemical reaction during the thermal processing. The fatigue crack growth experiments were conducted with specimens having the fiber orientation normal to the crack growth direction (longitudinal) and also specimens with the fibers oriented parallel to the crack growth direction(transverse). A comparison of the fatigue crack growth behavior indicates that aged longitudinal specimens are more resistant to fatigue crack growth the as-fabricated longitudinal specimens. Conversely, as-fabricated transverse specimens are more resistant to fatigue crack growth than aged transverse specimens.

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Numerical Analysis of Effect of Inhomogeneous Pre-mixture on Pressure Rise Rate in HCCI Engine by Using Multizone Chemical Kinetics (화학반응수치해석을 이용한 HCCI기관의 예혼합기의 성층화성이 연소시의 압력 상승률에 미치는 영향)

  • Lim, Ock-Taeck
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.5
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    • pp.449-456
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    • 2010
  • The HCCI engine is a prospective internal combustion engine with which high diesel-like efficiencies and very low NOx and particulate emissions can be achieved. However, several technical issues must be resolved before HCCI engines can be used for different applications. One of the issues concerning the HCCI engine is that the operating range of this engine is limited by the rapid pressure rise caused by the release of excessive heat. This heat release is because of the self-accelerated combustion reaction occurring in the engine and the resulting engine knock in the high-load region. The purpose of this study is to evaluate the role of thermal stratification and fuel stratification in reducing the pressure rise rate in an HCCI engine. The concentrations of NOx and CO in the exhaust gas are also evaluated to confirm combustion completeness and NOx emission. The computation is carried out with the help of a multizone code, by using the information on the detailed chemical kinetics and the effect of thermal and fuel stratification on the onset of ignition and rate of combustion. The engine is fueled with dimethyl ether (DME), which allows heat release to occur in two stages, as opposed to methane, which allows for heat release in a single stage.

Anti-hyperalgesic Effects of Electroacupuncture Combination of Microcurrent Stimulation in Rat with Induced Inflammation (염증유발 백서에서 전침자극과 미세전류자극의 항-통각과민 효과)

  • Kim, Young-Phil;Lee, Jeong-Woo;Seo, Sam-Ki;Yoon, Se-Won;Yoon, Hui-Jong;Kim, Tae-Youl
    • The Journal of Korean Physical Therapy
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    • v.19 no.1
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    • pp.67-78
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    • 2007
  • Purpose: The purpose of this study were to examine the anti-hyperalgesic effects of combination of electroacupuncture and microcurrent on anti-hyperalgesia in local hyperalgesia zone. Methods: It used 24 rats for experiment, divided them into control group, electroacupuncture group (EA group), microcurrent group (MC group), combination of electroacupuncture with microcurrent (EA+MC group), caused hyperalgesia by injecting ${\lambda}-carrageenan$ into hindpaw. Thickness of hindpaw, mechanical pain threshold (MPT), thermal pain threshold (TPT), noxious flexion withdrawal reflex (NFR) and somatosensory evoked potential (SEP) were measured immediately after induction, at 24 hours, 48 hours and 72 hours after induction. The electrical stimulation was given once a day for three days, 20min per session. Results: Change of thickness, MPT, and TPT showed significant difference in all groups compared to control group. In particular, there were remarkable difference in EA+ME group. In particular there were remarkable differences in EA group and EA+MC group. Change of NFR(% threshold, % reaction time, % RMS) and SEP showed mainly significant differences in EA group and EA+ME group compared to control group. In particular, there were remarkable difference in EA+ME group. Conclusion: The above results suggest that appropriate combination of microcurrent with electroacupuncture for pain control will be very desirable.

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Improvement of Single Anaerobic Reactor for Effective Nitrogen Removal (효율적 질소제거를 위한 단일 혐기성반응조의 개선)

  • 한동준;류재근;임연택;임재명
    • Journal of environmental and Sanitary engineering
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    • v.12 no.3
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    • pp.9-17
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    • 1997
  • This research aims to remove nitrogen in the piggery wastewater by combined process with upflow anaerobic sludge blanket (UASB) and biofilm process. For the effective denitrification. anaerobic and anoxic reactors were connected to a reactor. The effluent of aerobix reactor was recycled equally with influent in the upper filter of anaerobic reactor for denitrification and outlet of UBF reactor was connected to the settling tank with $1.5{\;}{\ell}$ capacity and the settling sludge was repeatedly recycled to UASB zone. The organic loading rate of total reactor was operated from 0.4 to $3.1kgCOD/m^{3}/d$ and it was observed that the removal rate of TCOD was 80 to 95 percentage. Ammonia nitrogen was removed over 90 percentage in the less volumetric loading rate than $0.1{\;}kgN/m^{3}/d$. But because of non-limitation of organic materials, it was reduced to 70 percentage in the more volumetric loading rate than $0.6{\;}kgN/m^{3}/d$. But denitrification rate was observed 100 percentage in the all of loading rate. This is caused by the maintenance of optimum temperature, sufficient carbon source, and competition of electron acceptors. The results of COD mass balance at the $1.21{\;}kgCOD/m^{3}/d$ was observed with the 71.7% percentage of influent COD. It was revealed that the most part of organic materials was removed in the aerobic and the anaerobic reactor because 38.4 percentage was conversed into $CH_{4}$ gas and 11 percentage was removed in the aerobic reactor with cell synthesis and metabolism. Besides, 5.7% organics was used to denitrification reaction and 3.7% organics related to sulfate reduction.

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Development of Environmental Evaluation Indicators for Environmentally Friendly Industrial Estate (환경친화적 산업단지 조성을 위한 환경성 평가 지표개발에 관한 연구)

  • Koo, Bon-Hak;Lee, Eun-Yeob
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.4
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    • pp.22-32
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    • 2000
  • Development of index for evaluation of environmental nature and its application for the purpose of construction of industrial complex with environmentally friendly. Industrial complex comes to be recognized as a disgusting zone according to the increasing environment consciousness of residents. And the objection about the exploitation of geographically unwanted land site is increased during development process and it is possible to cause Nimby phenomenon. Therefore, ecology and environment-oriented strategies tends to be adopted for industrial complex development. Furthermore, the maximization of profit mainly directed by enterprises as of today cannot guarantee its future and the efforts of adopting environmental constancy and harmony as a new objective are made progressively. For the development of city and region, in particular such as residence complex, farming and special city, the discussion of environmental consistency, new paradigm with environmentally friendly is briskly under progress, but the relevant discussion for the development of industrial estate is not done so much. Just only few studies are realized from the viewpoint of industrial ecology but its level remains in the understanding of the concepts and presentation of development direction. This study is to prepare for the foundation of the construction of industrial estate with environmentally friendly under the current condition of Korea against coming future environment era and to try to develop of evaluation range and index which are the basis of evaluation of environment. I applied the above evaluation index to the residents of actual industrial estate to understand their consciousness of decreased environment. And I obtained 7 evaluation ranges and 37 evaluation indexes for the relevant residents. Among them, I get the value less than the average in 19 index items. And they represent very sensible reaction about environment pollution including decrease of waste materials. This study has several limits but is meaningful in that the development of evaluation index for environmental nature in industrial complex is done, and that the basic discussion of the plan and design for environmentally friendly industrial estate is made under the above evaluation and that 37 evaluation items are applied to the reality.

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A New Groutability Criterion of Cement-based Grout with Consideration of Viscosity and Filtration Phenomenon (점도변화와 흡착현상을 고려한 시멘트계 그라우트재의 새로운 침투 기준)

  • Kim, Jong-Sun;Lee, In-Mo;Lee, Mun-Seon;Choi, Hang-Seok
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.154-163
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    • 2009
  • The groutability depends on the properties of the grout, its injection processes, and on the mechanical properties of the soil formation. During the process of pouring cement-based grouting into a porous medium, a variation with time occurs in the viscosity of grout suspension. In addition the particle filtration phenomenon will limit the expansion of the grouted zone because cement particles are progressively stagnant within the soil matrix. In this paper, a closed-form solution was derived by implementing the mass balance equations and the generalized phenomenological filtration law, which can be used to evaluate the deposition of cement-based grout in the soil matrix. The closed-form solution relevant to a particular spherical flow was modified by a step-wise numerical calculation, considering the variable viscosity caused by a chemical reaction, and the decrease in porosity resulting from grout particle deposition in the soil pores. A series of pilot-scale chamber injection tests was performed to verify that the developed step-wise numerical calculation is able to evaluate the injectable volume of grout and the deposition of grout particles. The results of the chamber injection tests concurred well with that of the step-wise numerical calculation. Based on the filtration phenomenon, a new groutability criterion of cement-based grout in a porous medium was proposed, which might facilitate a new insight in the design of the grouting process.

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Magnetic Properties of Multiferroic h-HoMnO3 (Multiferroic h-HoMnO3의 자기적 성질 연구)

  • Kim, Sung-Baek;Kum, Bok-Yeon;Kim, Chul-Sung;An, Sung-Yong;Park, N.Hur, S.;Cheong, S.W.;Jang, Kwang-Hyun;Park, J.G.
    • Journal of the Korean Magnetics Society
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    • v.15 no.2
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    • pp.113-117
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    • 2005
  • Multiferroic $HoMnO_3$ single crystal was prepared using 4-point focused floating zone furnace, and polycrystalline $HoMn_{1-x}\;^57Fe_xO_3$ (x=0.00, 0.01, 0.02, 0.05) powders have been prepared by solid state reaction. Their magnetic and crystallographic properties are studied using MPMS, PPMS, and $M\ddot{o}ssbauer$ spectroscopy. The crystal structure found to be a hexagonal and a magnetic easy-axis is (110) direction. As the external applied magnetic field increases, temperature of the dielectric constant anomaly is decreased. $HoMn_{0.95}\;^{57}Fe_{0.05}O_3$ shows huge quadrupole splitting value from the $M\ddot{o}ssbauer$ spectra.