• Title/Summary/Keyword: Reaction solution

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Phenolphthalein Solution Discoloration determined by alkali concentration in long-term concrete check surface (장기재령 콘크리트의 할렬면에서 알칼리농도에 의한 페놀프탈레인 용액의 변색)

  • Park, Hyun;Lee, Jong-Rok;Kim, Kwang-Ki;Kim, Woo-Jae;Kim, Jong-Sub;Jung, Sang-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.05a
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    • pp.183-186
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    • 2008
  • Carbonation is measured as Phenolphthalein Solution, it is possible to confirm the scope of alkali through acid and basic reaction. Then, Concrete Basic Reaction is decided according to alkali concentration depending on Potassium Hydroxide Now that Carbonation is gradually produced toward inner side from outer side, with time going by, it doesnt work, to some adequate depth, in as fast time as compulsory facilitating test. Thus, this research thesis made a comparative analysis on concrete phenomenal discoloration borderline following Phenolphthalein Solution, as part of a bid to measure Carbonation. Also, the thesis measured Concrete Alkali Concentration. The result showed that concrete coloring is classified into red and scarlet according to alkali concentration, and into borderline breakpoint of the speckle of scarlet and carbonation reaction. The higher chroma becomes with concrete decolorizing, the higher alkali concentration becomes.

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An experimental study of Antiallergic activity of Medicinal Acupunture Solution of Acanthopanax senticosus(Rupr. et Maxim.) (자오가피(刺五加皮) 약침액(藥針液)의 항(抗)알러지 효과(效果)에 대한 실험적(實驗的) 연구(硏究))

  • Yoon, Jong-Tae;Seol, In-Chan;Kim, Dong-Hee;Kim, Sung-Hoon;Kim, Han-Sung
    • Journal of Acupuncture Research
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    • v.18 no.2
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    • pp.136-149
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    • 2001
  • Objetives : This study was done to evaluate the antiallegic effect of medicinal acupuncture solution of Acanthopanax senticosus(Rupr. et Maxim;abbreviated as ASMA), studies were done experimentally. Methods : For this aim MTT assay, anaphylaxis reaction, DTH, histamine release, IgE production and vascular permability was evaluated. Results : ASMA didn't show an effective cytotoxicity on the mouse lung fibroblast. It insignifcantly suppressed histamine release from mast cells induced by compound 48/80, while it significantly reduced IgE production and SRBC-challenged DTH(Delayed type hypersensitivity). ASMA effectively suppressed anaphylactic reaction induced by compound 48/80. However, it didn't inhibit vascular permeability and contact dermatitis significantly. Conclusion:Medicinal acupucture solution had antialletgic effects. Acanthopanax senticosus medical acupuncture depress the allergy reaction. Especially in anaphylactic type, the effect was good.

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A Fuel Feasibility Study of Sewage Sludge by Melting of Thermoplastic Polyethylene

  • Lee, Byeong-Kyu;Jeong, Wang-Seok
    • Journal of Environmental Science International
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    • v.19 no.1
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    • pp.9-16
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    • 2010
  • This pilot study evaluated fueling feasibility of sewage sludge, which contains a large amount of water content, by applying melting of thermoplastic polyethylene (PE). This study has identified a simultaneous achievement of drying and heating value improvement of the sewage sludge. The sewage sludge collected from a sewage sludge treatment plant during a winter period had a water content of 83.7 wt%, a combustible volatile content of 12.5 wt%, and an ash content of 3.8 wt%. The higher heating value (HHV) of the dried sewage sludge, before impregnation or coating of PE, was 4,600 kcal/kg. The collected sewage sludge was immersed into the melted PE solution, which had a HHV of 11,070 kcal/kg, and kept immersing with increasing reaction time. As the reaction (immersing or coating or impregnation) time increased, the water content of the sludge decreased. However, the HHV of the sludge increased with increasing the reaction time. The HHVs of the sewage sludge immersed or dipped into the melted PE solution for 15 min ranged from 6,780 to 8,170 kcal/kg with water content less than 7 wt%. This result indicates the melted PE solution can be utilized as an improvement technology for dryness and heating value of the sewage sludge with high water content. The sewage sludge impregnated or coated with melted PE can be utilized as potential fuel or energy resources.

Solution Plasma Synthesis of BNC Nanocarbon for Oxygen Reduction Reaction

  • Lee, Seung-Hyo
    • Journal of the Korean institute of surface engineering
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    • v.51 no.5
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    • pp.332-336
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    • 2018
  • Alkaline oxygen electrocatalysis, targeting anion exchange membrane alkaline-based metal-air batteries has become a subject of intensive investigation because of its advantages compared to its acidic counterparts in reaction kinetics and materials stability. However, significant breakthroughs in the design and synthesis of efficient oxygen reduction catalysts from earth-abundant elements instead of precious metals in alkaline media still remain in high demand. One of the most inexpensive alternatives is carbonaceous materials, which have attracted extensive attention either as catalyst supports or as metal-free cathode catalysts for oxygen reduction. Also, carbon composite materials have been recognized as the most promising because of their reasonable balance between catalytic activity, durability, and cost. In particular, heteroatom (e.g., N, B, S or P) doping on carbon materials can tune the electronic and geometric properties of carbon, providing more active sites and enhancing the interaction between carbon structure and active sites. Here, we focused on boron and nitrogen doped nanocarbon composit (BNC nanocarbon) catalysts synthesized by a solution plasma process using the simple precursor of pyridine and boric acid without further annealing process. Additionally, guidance for rational design and synthesis of alkaline ORR catalysts with improved activity is also presented.

The Study on Solid-State Reaction Between MgO Single Crystal and $Fe_2O_3$ Powder (단결정 MgO와 분말 $Fe_2O_3$간의 고상 반응 연구)

  • 김성재;박재우
    • Journal of the Korean Ceramic Society
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    • v.32 no.2
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    • pp.234-238
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    • 1995
  • MgFe2O4 formation, grain growth in Fe2O3, Fe solid-solution limit in MgO for MgO-Fe2O3 mixture were studied by means of investigating the distribution of phases and compositions in reaction area between MgO and Fe2O3. The reaction area at equlibrium was composed with MgO-FexO matrix and MgFe2O4 precipitation, MgFe2O4 was formed by precipitating from MgO-FexO matrix dependent on oxygen partial pressure. Fe contents was exponentially decreased with diffusion distance in MgO single crystal, and thus Fe solid-solution limitation in MgO was about 4mol%. The grain growth rate in Fe2O3 base was increased with Mg contents diffused from MgO single crystal.

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Effects of Methacrylamide Treatment on Silk Fibers I. Effects of Reaction Conditions on Weight Increase of Silk Fibers (견섬유에 대한 메타크릴아미드의 처리효과 I. 반응조건에 따른 견섬유의 무게 증가)

  • 신태섭;남중희
    • Journal of Sericultural and Entomological Science
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    • v.33 no.2
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    • pp.82-86
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    • 1991
  • The treatments of methacrylamide on silk fibers were studied in aqueous solution using potassium persulfate as an initiator, and suitable conditions of reaction were determined for weighing of silk fibers. The results obtained were summarized as follows ; The weight of MAA-treated silk fibers increased with monomer concentration. The adequate concentration of potassium persulfate was found to be 1.7%. Maximum weight increase was shown at initial pH 3.8 of reaction liquor controlled by buffer solution.

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The Dissociation Constants of Valines in Aqueous Solution (수용액 중에서 발린류의 해리상수)

  • Jung-Ui Hwang;Yong-Woo Kwak;Jae-Won Jung;Chon-Ho Kil
    • Journal of the Korean Chemical Society
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    • v.35 no.2
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    • pp.105-110
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    • 1991
  • The dissociation constants of valine and norvaline in aqueous solution were measured by conductometric method in various temperatures and pressures. The properties of the dissociation reaction were discussed in term of the thermodynamic properties of reaction. These substituted effects on the dissociation reaction were discussed on the points of Hammett relation and net charge of the O and N-atom calculated from CNDO/2 method respectively.

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Formation Reaction of Mn-Zn Ferrite by Wet Process (습식합성에 의한 Mn-Zn Ferrite의 생성반응에 관한 연구)

  • 이경희;이병하;허원도;황우연
    • Journal of the Korean Ceramic Society
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    • v.30 no.1
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    • pp.25-33
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    • 1993
  • Formation reaction of Mn-Zn ferrite depending on various synthetic conditions of wet process was investigated using FeCl2.nH2O(n≒4), MnCl2.4H2O, ZnCl2 as starting materials. A stable intermediate precipitate was formed by the addition of H2O2. And the precipitate was hard to transform to spinel phase of Mn-Zn Fe2O4. Single phase of Mn-Zn Fe2O4 spinel was obtained above 8$0^{\circ}C$ reaction temperature. The powder had spherical particle shape and 0.02~0.05${\mu}{\textrm}{m}$ particle size. Fe(OH)2 solid solution, -FeO(OH) solid solution, -FeOOH, Mn-Zn Fe2O4 spinel were formed with air flow rate 180$\ell$/hr. However, single phase of Mn-Zn Fe2O4 spinel with cubic particle shape and 0.1~0.2${\mu}{\textrm}{m}$ particle size was formed with synthetic conditions of 8$0^{\circ}C$ and 90 munutes. The particle shape of the -FeOOH was needle-like.

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Hydrogen Prodution by Sulfur Thermochemical Water Splitting Cycle: Part 1. H2O-SO2-I2 Reaction and Separation (황 - 요오드의 열화학적 물분리에 의한 수소제조연구 Part I. 물-이산화황-요오드 반응 및 분리)

  • Lee, K.I.;Min, B.T.;Kwon, S.G.;Kang, Y.H.
    • Transactions of the Korean hydrogen and new energy society
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    • v.1 no.1
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    • pp.40-47
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    • 1989
  • The sulfur-iodine thermochemical water splitting process of GA(General atomic) cycle was studied to produce hydrogen from water by $H_2-I_2-SO_2$ reactions. The experimental scale was 500g based on iodine. The reaction took 100 minutes, products could be separated two liquid phases due to their density difference:HI solution had a density of 2.39~2.61g/cc, and $H_2SO_4$ solution had 1.37~1.38g/cc. The condition of reaction was when weight ratio of $I_2/H_2O$ was 2/1 resulting in good phase separation and productivity.

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Studies on the Zr-Pyrithione Complex (지르코늄-피리치온 착물에 관한 연구)

  • Kwon, Chung-Moo;Rhee, Gye-Ju
    • Journal of Pharmaceutical Investigation
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    • v.20 no.3
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    • pp.145-152
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    • 1990
  • Zirconium pyrithione complex was prepared by reaction of sodium-pyrithione solution and zirconyl chloride solution. The physico-chemical properties of the complex was examined by means of IR, XRD, DSC and NMR. And the stability of Zr-complex was investigated on the basis of accelerated stability analysis under conditions of temp. elevation, UV radiation and pH dependence. The result indicates that the ratio of the ligand to metal in Zr-pyrithione complex was determined 4:1, and its stability constant was $4.643{\times}10^4$. The rate order of decomposition of the complex was apparent first-order reaction of which rate constant and the decomposition rate was not only accelerated by effect of heat and UV radiation but was catalyzed by specific acid-base catalysis considered the pH dependence for the hydrolysis of the complex and the suspension was most stable over the range pH 4-8 indicating that solvent catalysis is the primary made of reaction in this region.

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