• Title/Summary/Keyword: reaction

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A Study of Reports about Dizziness Reaction - Focus on the China Academic Journal - (명현(瞑眩) 반응에 대한 보고 연구 - China Academic Journal을 중심으로 -)

  • Yoon, Cheol-Ho
    • The Journal of Korean Medicine
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    • v.30 no.5
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    • pp.1-15
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    • 2009
  • Objectives: I carried out this study for research on dizziness (瞑眩) reaction. Methods: I found 14 papers about dizziness reaction from 1994 to 2009 in China Academic Journal (CAJ) website, and synthesized these reports. Results: Dizziness reaction, presupposing that the diagnosis and treatments are correct, is a peculiar reaction which occurs with severe and various symptoms temporarily diverging from regular course. As dizziness reaction disappears, the symptoms of the disease are improved. Though it mostly occurs rapidly and disappears in a short time, it can occur after a long treatment or occur gradually in chronic diseases. As a general rule, the faster dizziness reaction occurs, the more severe the reaction. The faster dizziness reaction disappears, the quicker the recovery from illness. Upon catching a disease, healthy qi(正氣) and the pathogen (邪氣) fight each other. Just at that moment, if the medicine or acupuncture treatment hits the mark of the pathogen (邪氣), healthy qi(正氣) attacks the origin of the disease in full force. Thus, all symptoms disappear at a time and various reactions occur which we can't accurately determine. So, we can call it 'Right action', 'Improving reaction' or 'Adjusting reaction'. Conclusions: It is difficult for us to predict whether a dizziness reaction will occur. Thus, we don't have to seek dizziness reaction blindly, and must distinguish dizziness reaction from side effects or toxic effects. So, we must pay more close attentions to symptom changes.

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The Reaction Probability and the Reaction Cross-section of N + O2→ NO + O Reaction Computed by the 6th-order Explicit Symplectic Algorithm

  • He, Jianfeng;Li, Jing
    • Bulletin of the Korean Chemical Society
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    • v.27 no.12
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    • pp.1976-1980
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    • 2006
  • We have calculated the reaction probability and the reaction cross-section of the $N(^4S)+O_2(X^3\sum_{g}^{-})\;\rightarrow\;NO(X^2\Pi)+O(^3P)$ reaction by the quasiclassical trajectory method with the 6th-order explicit symplectic algorithm, based on a new ground potential energy surface. The advantage of the 6th-order explicit symplectic algorithm, conserving both the total energy and the total angular momentum of the reaction system during the numerical integration of canonical equations, has firstly analyzed in this work, which make the calculation of the reaction probability more reliable. The variation of the reaction probability with the impact parameter and the influence of the relative translational energy on the reaction cross-section of the reaction have been discussed in detail. And the fact is found by the comparison that the reaction probability and the reaction cross-section of the reaction estimated in this work are more reasonable than the theoretical ones determined by Gilibert et al.

Treatment of nitrobenzene-cotaminated Wastewater using Oxidation Reaction (산화제를 이용한 니트로벤젠 함유 폐수 처리)

  • 신진환;손종렬
    • Journal of environmental and Sanitary engineering
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    • v.17 no.1
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    • pp.69-74
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    • 2002
  • This study explored for treatment processes by investigating the treatment efficiency and reaction mechanism through oxidation reaction using UV and $O_3$ as oxidant in compensate the wastewater containing nitrobenzene that is non biodegradable organic. Also by modeling these reactions, we try to step explanation of optimum reaction rate and reaction mechanism as the development of the computer program predictable the reaction rate by modeling the reaction. By using this model, after kinetic constant for each reaction from an experimental data is made an optimization and for hardly contribute to reaction rate in reaction kinetic equation is made an ignorance and suppose the simplified reaction mechanism, examined the propriety of computer simulation model and simplified reaction mechanism by comparing and inspecting the reaction kinetic constant and masstransfer coefficient. An investigation results for destructional treatment of nitrobenzene in the wastewater as non-biddegradable organic using UV, $O_3{\;}O_2{\;}H_2O_2-UV$ as oxidant.

A Parametric Study of Pervaporation-facilitated Esterification (전산모델링을 통한 투과증발-촉진 에스테르화 반응에 대한 연구)

  • Yeom, C.K.;Choi, Seung-Hak;Park, You-In;Chang, Sung-Soon
    • Membrane Journal
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    • v.17 no.2
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    • pp.146-160
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    • 2007
  • A parametric study on pervaporation-facilitated esterification was performed by using a practical model based on non-perfect separation through membrane which is not perfectly permselective to water. Thus, membrane selectivity as well as membrane capability to remove water should be taken into account in establishing the simulation model to explain how the membrane separation influence the esterification reaction process. It was shown by simulation that in the reaction systems with non-perfect separation, the permeation of reactants which are acid or/and alcohol retards the reaction by inducing the backward reaction so that reaction conversion curve is located between a reaction system coupled with pervaporation process having a perfect permselectivity to water and a reaction system without pervaporation process. The volume change of reaction system occurs as a result of the permeation through the membrane. The reaction volume change which can be characterized by the reaction ratio of $r_{\Psi}\;to\;r_{{\Psi}=1}$ affects reaction kinetics by concentrating reactants and products, respectively, with different extent with time; reactant-concentrating effect is dominant during the initial stage of reaction, resulting in facilitating the reaction, and then product-concentrating effect is exerted more on reaction, causing to slow down the reaction. When pervaporative dehydration is applied to the reaction system plays an important role in the reaction as well. The effect of timing to impose pervaporation on reaction system affected the reaction kinetics in terms of reaction rate and reaction conversion. A relationship was derived to explain membrane unit capacity and reaction parameters that will be used as a design tool to determine membrane unit capacity at a given reaction conditions or reaction parameters at a membrane unit capacity.

Nonlinear Entropy Production in a Reversible Oregonator Model

  • Basavaraja, C.;Pierson, R.;Park, Seung-Hyun;Jeon, Eun-Ji;Huh, Do-Sung
    • Bulletin of the Korean Chemical Society
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    • v.29 no.5
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    • pp.1051-1054
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    • 2008
  • The entropy production in a non-equilibrium state based on the reversible Oregonator model of the Belousov-Zhabotinskii (BZ) reaction system has been studied. The reaction affinity and the reaction rate for the individual steps have been calculated by varying the concentrations of key variables in the system. The result shows a linear relationship between the reaction affinity and the reaction rate in the given concentration range. However, the overall entropy calculated on the basic assumption that the entropy in a reaction system corresponds to the summation of a product of reaction affinity and reaction rate of individual steps shows a nonlinearity of the reaction system. The results well agrees with the fact that the entropy production is not linear or complicated function in a non-linear reaction system.

Browning Reaction of Fresh Ginseng (Panax ginseng C.A. Meyer) as Affected by Heating Temperature (가열온도에 따른 수삼의 갈변반응 특성)

  • 이종원;이성계
    • Journal of Ginseng Research
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    • v.19 no.3
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    • pp.249-253
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    • 1995
  • In the browning reaction of Korean ginseng, it appears that enzymatic and non-enzymatic browning reaction occurred in the initial stage of heating fresh ginseng at low temperature, and then non-enzymatic browning reaction followed in the drying period after heating. Activation energy of the browning reaction for red ginseng was about 9.0 kcal/mol. Browning reaction of red ginseng was accede- rated with an increase in steaming time, and a great extent of browning reaction occurred between 60-90 min of steaming at 10$0^{\circ}C$. Browning pigments of red ginseng were mostly water soluble subset.

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Characteristics of Transesterification Reaction of Soy Bean Oil by Acid Catalysts (산촉매에 의한 대두유의 전이에스테르화 반응 특성)

  • Shin, Yong-Seop
    • Journal of Environmental Science International
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    • v.18 no.2
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    • pp.231-238
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    • 2009
  • Characteristics of the transesterification reaction between triglycerides in soy bean oil and methanol were investigated in the presence of acid catalysts. such as sulfuric acid and PTS (p-toluene sulfonic acid). Concentrations of diglyceride and monoglyceride which were intermediates in the reaction mixtures, were far below 10% of triglyceride under any reaction conditions. Thus, conversion of the reaction could be determined from the concentration of triglyceride. Dried PTS had more superior catalytic power than sulfuric acid for transesterification reaction between soy bean oil and methanol. When transesterification reaction of soy bean oil was catalyzed by 1 wt% of PTS at methanol stoichiometric mole ratio of 2 and $65^{\circ}C$, final conversion reached 95% within 48 hours. If FAME (fatty acid methyl ester) was added into reaction mixture of soy bean oil, methanol and PTS catalyst, it converted reaction mixture into homogeneous phase, and substantially increased reaction rate. When reaction mixture was freely boiling which had equal volumetric amount of FAME to soy bean oil, methanol stoichiometric mole ratio of 2 and 1 wt% of PTS, final conversion achieved value of 94% and temperature approached to $110^{\circ}C$ within 2 hours.

Synthesis of Silicon Carbide Whiskers (I) : Reaction Mechanism and Rate-Controlling Reaction (탄화규소 휘스커의 합성(I) : 반응기구의 율속반응)

  • 최헌진;이준근
    • Journal of the Korean Ceramic Society
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    • v.35 no.12
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    • pp.1329-1336
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    • 1998
  • A twt -step carbothermal reduction scheme has been employed for the synthesis of SiC whiskers in an Ar or a H2 atmosphere via vapor-solid two-stage and vapor-liquid-solid growth mechanism respectively. It has been shown that the whisker growth proceed through the following reaction mechanism in an Ar at-mosphere : SiO2(S)+C(s)-SiO(v)+CO(v) SiO(v)3CO(v)=SiC(s)whisker+2CO2(v) 2C(s)+2CO2(v)=4CO(v) the third reaction appears to be the rate-controlling reaction since the overall reaction rates are dominated by the carbon which is participated in this reaction. The whisker growth proceeded through the following reaction mechaism in a H2 atmosphere : SiO2(s)+C(s)=SiO(v)+CO(v) 2C(s)+4H2(v)=2CH4(v) SiO(v)+2CH4(v)=SiC(s)whisker+CO(v)+4H2(v) The first reaction appears to be the rate-controlling reaction since the overall reaction rates are enhanced byincreasing the SiO vapor generation rate.

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Manufacturing of Meat Flavor Extract used for Browning Reaction (Browning Reaction을 이용한 Meat Flavor Extract의 개발)

  • Kim Duk-Sook;Kim Jong-Seung
    • The Korean Journal of Food And Nutrition
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    • v.17 no.3
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    • pp.313-321
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    • 2004
  • Separation-concentration of sulfur containing heterocyclic compounds(SCHC) from many reaction meat flavors manufactured with Maillard reaction was carried out. Profile of SCHC was identified and analyzed by GC and GC-MSD. The results were as follows. 1. Profile of SCHC could be identified 7 kinds thiazole and 11 kinds thiophene, the major produced compounds were thiophene, thiazolidine, 4-methyl-5-thiazole ethanol. 2. In the case of SCHC, relationship between changes of reaction conditions and the kind of produced components were as same, but produced amounts appeared the difference. Producing amount of complexed SCHC and caramellike note as well as oxygen containing heterocyclic compounds were high level more than high reaction temperature and long time reaction period. 3. Producing ratio of comparative simple structural SCHC were the highest level at reaction conditions of moisture content 50%, reaction temperature 100$^{\circ}C$ and reaction time 2 hours. Reaction conditions for the revelation of reaction meat flavor were below 110$^{\circ}C$ and less than 2 hours. 4. Relationship between moisture content and reaction temperature as well as reaction time had very relative relation. From the change of moisture content and reaction conditions could be obtained the simultaneously profile. Signal presentation for production of reaction meat flavor could be from extraction-separation-concentration of SCHC through simplification of raw-materials in the flavor and seasoning food industry.

Properties of Reaction Rim on Blast Furnace Slag Grain with Alkali Activator according to Hydration Reaction (알칼리 자극제(刺戟劑)에 의해 고로(讀爐) 수쇄(水碎) 슬래그의 주위(周圍)에 형성(形成)된 Reaction Rim의 특성(特性))

  • Lee, Seung-Heun;Mun, Young-Bum
    • Resources Recycling
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    • v.18 no.3
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    • pp.42-48
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    • 2009
  • Since there are $OH^-,\;[SiO_4]^{4-}$ ion of high concentration at early hydration in the system added with activator (NaOH+$Na_2OSiO_2$) in the blast furnace slag, different from cement hydration, hydration progresses fast without induction period and forms reaction rim around the blast furnace slag grain. $0.6{\mu}m$ reaction rim was formed around the blast furnace slag grain from the 1 day of reaction period, and the thickness of reaction rim increases over the reaction time, growing to $1{\mu}m$ on the 28 days. Unreacted blast furnace slag grain deformed from angular shape to the spherical shape. Mole ratio of Ca/Si tends to decrease from inside of blast furnace slag grain to reaction rim. Difference of Ca/Si mole ratio between reaction rim and inside the blast furnace slag grain decreased and generated hydrate was a poor crystalline CSH(I) with Ca/Si mole ratio less than 1.5.