• 제목/요약/키워드: Reaction media

검색결과 605건 처리시간 0.036초

비에테르성 용매중에서 에테르촉매를 사용한 그리냐르반응에 의한 유기스탄닐화합물의 합성 (The Syntheses of Organostannyl Compounds by Grignard Reaction Catalyzed by Ether in Non-ethereal Media)

  • 서배석;이일규
    • 대한화학회지
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    • 제23권6호
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    • pp.392-395
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    • 1979
  • 몇가지 유기할로겐화물, 즉 브롬화에틸, 염화부틸, 브롬화페닐 및 염화벤질등을 탄화수소중에서 그리냐르법으로 무수사염화주석과 반응시켰다. 이때 소량의 에테르를 그리냐르반응단계에서 계내에 투입하엿을 때 보다 용이하게 반응이 진행되어 좋은 수율로 유기주석화합물들을 얻을 수 있었다.

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상향류 및 하향류 생물막여과공정의 처리특성에 관한 연구 (Treatment Characteristics of Biological Aerated Filter Process Using the Upflow and Downflow System)

  • 이양규;김건협
    • 상하수도학회지
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    • 제20권6호
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    • pp.837-848
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    • 2006
  • This paper presents the test results of biological aerated filtration(BAF) process to replace activated sludge process by enhancing treated effluent quality and reducing the costs. In BAF process both BOD and SS compounds in wastewater are degraded and removed by biological reaction and filtration. Upflow BAF with expanded polypropylene media and downflow BAF with ceramic media were used to investigate the effects of hydraulic and organic loads on effluent quality. As a result, in BAF processes which has different media, upflow BAF reactor shows 5% higher efficiency than downflow BAF and this phenomena caused by backwashing methods and operational conditions. The results of influence factors analyzed by Factor Analysis Method in BOD and SS treatment efficiency are the size of media, hight of media bed and type of media. The quantitative effects of media size are 5.73% in TBOD, 5.78% in SBOD and 7.65% in TSS, so we confirmed the main factor is media size.

Properties of the Microinterface formed by Phosphatidylcholine and 1-Butanol as Reaction Media of Hydrolysis of Phosphatidylcholine

  • Yamazaki, Keiju;Imai, Masanao;Suzuki, Isao
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.82-85
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    • 2004
  • Microinterface of W/Omicroemulsion prepared by phosphatidylcholine was used as reaction media of hydrolysis of phosphatidylcholine by phospholipaseA$_2$. Phosphatidylcholine was used as an amphiphile and was acted as a substrate. Organic phase of W/Omicroemulsion in this study was prepared by mixed organic solvents i.e. 2,2,4-trimethylpentane (isooctane) as a main solvent and 1-butanol as a co-solvent. The effect of added 1-butanol was remarkable not only on reaction beginning but also on high reaction rate. The hydrolysis reaction was dramatically initiated when 1-butanol was injected into the running isooctane/PC system. The enhancement by 1-butanol addition into single organic solvent was our original finding compare with previous conventional organic solvent. The reaction rate was elevated by the added amount of 1-butanol. The enhanced reaction rate was about 150-folds. This enhancement was speculated as 1-butanol adsorption on the microinterface. The adsorbed 1-butanol improved the properties of microinterface, especially its mobility was increased by difference of the chain length between phosphatidylcholine and 1-butanol. PhospholipaseA$_2$ molecules were located on the microinterface due to modified mobility of microinterface. Located phospholipaseA$_2$ on the microinterface reacted easily with phosphatidylcholine molecule. As a result high reaction rate was obtained. Microinterfacial properties were successfully improved by adsorbed 1-butanol molecule, and were favorable to appear higher reactivity of phospholipaseA$_2$.

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Kinetic and Mechanistic Studies of Oxidation of an Antiallergic Drug with Bromamine-T in Acid and Alkaline Media

  • Puttaswamy, Puttaswamy;Sukhdev, Anu
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3544-3550
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    • 2012
  • Cetrizine dihydrochloride (CTZH) is widely used as an anti-allergic drug. Sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) is the bromine analogue of chloramine-T (CAT) and is found to be a better oxidizing agent than CAT. In the present research, the kinetics of oxidation of CTZH with BAT in acid and alkaline media was studied at 313 K. The experimental rate laws obtained are: -d[BAT]/dt=$k[BAT][CTZH]^{0.80}[H^+]^{-0.48}$ in acid medium and -d[BAT]/dt=$k[BAT][CTZH]^{0.48}[OH^-]^{0.52}[PTS]^{-0.40}$ in alkaline medium where PTS is p-toluenesulfonamide. Activation parameters and reaction constants were evaluated. The solvent isotope effect was studied using $D_2O$. The dielectric effect is positive. The stoichiometry of the reaction was found to be 1:1 and the oxidation products were identified as 4-chlorobenzophenone and (2-piperazin-1-yl-ethoxy)-acetic acid in both media. The rate of oxidation of CTZH is faster in acid medium. Suitable mechanisms and related rate laws have been worked out.

Highly Stable Photoluminescent Qunatum Dot Multilayers by Layer-by-Layer Assembly via Nucleophilic Substitution Reaction in Organic Media

  • 윤미선;김영훈;정상혁;백현희;조진한
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2011년도 춘계학술발표대회
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    • pp.244.2-244.2
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    • 2011
  • We introduce a novel and robust method for the preparation of nanocomposite multilayers, which allows the excellent photoluminescent (PL) properties as well as the accurate control over the composition and dimensions of multilayers. By exchanging the oleic acid stabilizers of CdSe@ZnS quantum dots (QDs) synthesized in organic solvent with 2-bromo-2-methylpropionic acid (BMPA) in the same solvent, these nanoparticles were be alternately deposited by nucleophilic substitution reaction with highly branched poly(amidoamine) dendrimer (PAMA) through layer-by-layer (LbL) assembly process. Our approach does not need to be transformed into the water-dispersible nanoparticles with electrostatic or hydrogen-bonding groups, which can deteriorate their inherent properties, for the built-up of multilayers. The nanocomposite multilayers including QDs exhibited the strong PL properties achieving densely packed surface coverage as well as long-term PL stability under atmospheric conditions in comparison with those of conventional LbL multilayers based on electrostatic interaction. Furthermore, we demonstrate that the flexible multilayer films with optical properties can be easily prepared using nucleophilic substitution reaction between bromo and amino groups in organic media. This robust and tailored method opens a new route for the design of functional film devices based on nanocomposite multilayers.

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영상매체 성메세지와 청소년의 성반응 - 성태도와 성행동을 중심으로 - (Sexual Messages in the Media and Sexual Reactions of Adolescents - Attitudes and Behaviors Toward Sex -)

  • 조주영;김영희
    • 대한가정학회지
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    • 제42권3호
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    • pp.159-178
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    • 2004
  • The purpose of this study was to investigate the effect of sexual messages in the media on adolescents' attitudes and behaviors toward sex. Subjects of this study consisted of 488 high school students in Cheong-ju City. The findings of this study were as follows; First, sexual messages in the media influenced-adolescents' attitudes toward sex. The more exposure to sexual messages adolescents had more liberal and permissive attitude toward sex. Secondly, sexual messages in the media also effected adolescents' behaviors toward sex, as well. The less sexual messages that they were exposed to, they displayed less sexual relations and behavior. In particular, the number of sexual materials in mass media, variety of sexual messages, and types of school were significant factors in predicting adolescents' sexual intercourse. The research suggested that sexual messages in the media definitely had an effect on adolescents' attitudes and behaviors toward sex. Therefore, it should be encouraged to take advantage of the television V chip and screening software for computers to reduce inappropriate access for adolescents.

알루미늄클로라이드 촉매를 이용한 Tricyclopentadiene 유도체의 이성화 반응 연구(I) (A Study on the Isomerization Reactions of Tricyclopentadiene Derivatives Using Aluminum Chloride(AlCl3) Catalyst(I))

  • 주현혜;권태수;박창선;한정식
    • 한국추진공학회지
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    • 제16권2호
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    • pp.17-24
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    • 2012
  • Tetrahydrotricyclopentadiene(이하 THTCPD)의 이성질체는 높은 밀도와 높은 발열량을 가지고 있어 고성능 액체 연료의 주요성분물질로 활용이 가능하다. 본 연구에서는 상온에서 고체 상태로 유동성이 좋지 않은 THTCPD를 유동성이 우수한 액체상태 특성을 가질 수 있게 할 수 있는 최적의 반응조건을 찾는 것이다. THTCPD의 이성화 반응은 반응온도 변화와 반응용매의 영향 등의 다양한 반응조건을 통해 살펴보았다. 알루미늄클로라이드 촉매를 사용하여 THTCPD 이성화 반응을 실험한 결과 Dichloromethane(Methylene Chloride: MC), 1,2-Dichloroethane(Ethylene Chloride: EC), Chloroform과 같은 할로겐 함유 극성용매가 n-Hexane, Toluene과 같은 비극성 탄화수소형 용매보다 이성화 반응에서 우수한 특성을 나타내었으며, 반응온도의 변화도 이성화반응에 크게 영향을 미치는 것을 알 수 있었다.

The “Trivial” Mechanism for the Photo-Fries Reaction of Phenyl Acetate and Biphenylyl Acetates

  • 윤효정;고성혜;고미경;최우기
    • Bulletin of the Korean Chemical Society
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    • 제21권9호
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    • pp.901-904
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    • 2000
  • The mechanism for the photo-Fries rearrangement of phenyl acetate andbiphenylyl acetates were reinvestigat-ed in phenol (or phenol derivatives) containing media. The results showed that the phenol (or phenol deriva-tives) which is the most common by-product of Fries reaction reacts with acyl radical togive Fries-product. These phenol (or phenol derivatives) contributions to the Fries-products were suggested as the Trivial mecha-nism for the photo-Fries reaction.

올리고피리디닐메틸렌아미노피리딘올과 금속 착화물의 합성, 분석 및 열분해 특성 연구 (Synthesis, Characterization, and Thermal Degradation of Oligo-2-[(pyridin-4-yl-)methyleneamino]pyridine-3-ol and Oligomer-Metal Complexes)

  • Kaya, Ismet;Gul, Murat
    • 폴리머
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    • 제32권4호
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    • pp.295-304
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    • 2008
  • This study examined the oxidative polycondensation reaction of 2-[(pyridin-4-yl-) methyleneamino] pyridine-3-ol (2-PMAP) using air $O_2$ and NaOCl oxidants at various temperatures and times in aqueous alkaline and acidic media. Under these reactions, the optimum reaction conditions using air $O_2$ and NaOCl oxidants were determined for 2-PMAP. The number-average molecular weight ($M_n$), weight average molecular weight ($M_w$), and polydispersity index (PDI) values of O-2-PMAP synthesized in aqueous alkaline media were found to be 960, 1230, and $1.281\;g\;mol^{-1}$ using NaOCl, and 1030, 1520, and $1.476\;g\;mol^{-1}$ using air $O_2$, respectively. At the optimum reaction conditions, the yield of O-2-PMAP in aqueous alkaline media was 92.50% and 85.70% for air $O_2$ and NaOCl oxidants, respectively. The yield of O-2-PMAP in aqueous acidic media was 88.5% and 88.0% for NaOCl and air $O_2$ oxidants, respectively. O-2-PMAP was characterized by $^1H-$, $^{13}C$-NMR, FT-IR, UV-vis, SEC, and elemental analysis. TGA-DTA analysis revealed O-2-PMAP and its oligomer metal complex compounds, such as $Co^{+2}$, $Ni^{+2}$, and $Cu^{+2}$, to be stable against thermal decomposition and their weight losses at $1000^{\circ}C$ were found to be 73.0, 58.0, 53.5%, and 50.0%, respectively. In addition, the antimicrobial activities of the monomer and oligomer were tested against E. Coli (ATCC 25922), E. Faecelis (ATCC 29212), P. Auroginasa (ATCC 27853), and S. Aureus (ATCC 25923).