• Title/Summary/Keyword: Dichlorobenzene

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A Convenient Preparation of Polychloroanisidine and Fluorochloroanisole Derivatives (Polychloroanisidine 및 Fluorochloroanisole 유도체의 간편한 합성)

  • Kim, Yu Seon;Kim, Tae Yeong;Kim, Yun Hui
    • Journal of the Korean Chemical Society
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    • v.18 no.4
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    • pp.278-288
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    • 1974
  • Starting from p-dichlorobenzene, 2-amino-4-chloroanisole could be prepared via a nitration, a methoxylation, and subsequent reduction. The repeated chlorination of 2-amino-4-chloroanisole resulted 2-amino-3,4,5-trichloroanisole without any isomeric products. The chlorination of 4-chloro-2-nitroanisole could easily give 2,4-dichloro-6-nitroanisole but polychlorination of the product could not be achieved at the atmospherical pressure. The repeated chlorination of 2-amino-4,6-dichloroanisole could give 2-amino-3,4,5,6-tetrachloroanisole, The Schiemann reaction of 2-amino-4-chloroanisole and 2-amino-4,6-dichloroanisole could give 2-fluoro-4-chloroanisole and 2-fluoro-4,6-dichloroanisole, respectively. The repeated chlorination of these fluorochloroanisoles could give 2-fluoro-3,4,5,6-tetrachloroanisole. In each chlorination process, the components of products were examined by means of NMR spectrometry and the chlorination reaction was repeated without isolating each isomeric product. The feasibility of the present routes of preparations was discussed in respects to the conveniency of reaction conditions and respective overall yields of the processes.

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Desorption Characteristics of Volatile Organics Compounds in Soil by Microwave Heating (마이크로파 가열에 의한 토양 유기오염물질 탈착특성)

  • 문경환;김덕찬
    • Journal of environmental and Sanitary engineering
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    • v.11 no.2
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    • pp.65-73
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    • 1996
  • The objective of this study is to investigate the removal efficiency of volitile organic compounds in soil, and the mechanism of desorption by bench scale microwave heating, Silt soil used for experiment and was impregnated with toluene, tetrachloroethylene, o-xylene and p-dichlorobenzene and the microwave treatment was conducted in a modified domestic microwave oven : 2450MHz, 700W. According to the results of the research the removal efficiency was improved with increasing water contents and the soil temperature appeared to plateau period extending to 2-3minutes corresponds to the temperature a which steam distillation was expected. The value of removal rate constant (k) were calculated on dry and moisty silt soil, respectively, which showed linear with increasing microwave heating time. Therefore, addition of a certain amount of water to the contaminated soil can efficiently enhance the ability of the soil to absorb microwave energy and promote the evaporation of the volitile contaminants.

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Studies on the Fish Kills by Histopathological Characteristics in Gills and Caudal Fins (아가미 혈종과 지느러미 표피탈락 현상을 이용한 어류 폐사원인 연구)

  • 최필선;최성수;이길철;윤준헌;박광식
    • Environmental Analysis Health and Toxicology
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    • v.11 no.3_4
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    • pp.45-51
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    • 1996
  • Histopathological changes of gills and caudal fins isolated from fishes, Cyprinus carpio, Carassius auratus, and Hernibarbus labeo, which were killed by oxygen deficiency or toxic chemicals, were studied. The toxic chemicals were HCl, NaOH, chloroform, benzene, heavy metals(Cu, Cr, Zn, Pb, Hg), and o-dichlorobenzene. The exposure level was enough to kill the fishes within 30 minutes. Oxygen deficient water was prepared by aeration of nitrogen gas and the oxygen concentration was less than l ppm. Cryocutting was used for the rapid preparation of tissue slides and the tissues were stained by hematoxylin/eosin. In the fishes killed by hazardous chemicals, congestion and/or hyperplasia of secondary lamella and erosion of fin were found as the major histopathological changes. Whereas, these characteristics were not observed in gills or caudal fins of fishes killed by oxygen deficiency. These different bioindications appeared in the fishes killed by toxic substances or natural causes, can be used for the rapid identification of the causes of fish kills.

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Effect of Genotoxicity or Carcinogenecity Chemicals on the ROS Production (유전독성, 발암성 화학물질이 ROS 생성에 미치는 영향)

  • Go, Seo-Youn;Sheen, Yhun-Yhong
    • Environmental Analysis Health and Toxicology
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    • v.23 no.1
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    • pp.23-32
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    • 2008
  • In the present study, ROS detection of L5178Y cells that were treated with twenty test compounds in order to find out hydrogen peroxide ($H_2O_2$) induction for genotoxicity and carcinogenic toxicity. Twenty test compounds were consist of four classes, such as genotoxic carcinogens, genotoxic noncarcinogens, nongenotoxic carcinogens, and nongenotoxic noncarcinogens. Genotoxic carcinogens are 1,2-dibromoethane, glycidol, melphalan, diethylstilbestrol and urethane. Genotoxic noncarcinogens are 8-hydroxyquinoline, emodin, acetonitrile and diallylphthalate, L-ascorbic acid. Nongenotoxic carcinogens are methyl carbamate, O-nitrotoluene, 1,4-dioxane, tetrachloroethylene and 2,3,7,8-tetrachlorodibenzo-p-dioxin. And nongenotoxic noncarcinogens are D-mannitol, 1,2-dichlorobenzene, caprolactam, bisphenol A and chlorpheniramine maleate.

Microwave Remediation of Soils Contaminated by Volatile Organic Chemicals (마이크로파에 의한 휘발성 유기토양오염물질 제거에 관한 연구)

  • 문경환;김우현;이병철;김덕찬
    • Journal of Environmental Health Sciences
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    • v.22 no.3
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    • pp.116-122
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    • 1996
  • This study has been focused on the applicability of microwave treatment of soil contaminated by volitile organic chemicals. Substrates studied were sand and sandy soil. These substrates were impregnated with toluene, tetrachloroethylene, o-xylene and p-dichlorobenzene. The microwave treatment was conducted in a modified domestic microwave oven: 2450 MHz, 700 W. The sandy soil temperature added water went up rapidly to about 130$\circ$C for 4 minutes. And then, the temperature appeared to plateau out. A series of tests were performed to depict the effectiveness of microwave treatment technique to organic contaminants from soils. Removal efficiencies in sandy soil and sand were increased with increasing water content and exposure time. Microwave radiation penetrates the soil and heats water throughout the matrix. Therefore, addition of a certain amount of water to the contaminated soil can efficiently enhance the ability of the soil to absorb microwave energy and promote the evaporation of the volitile contaminants. And the vapour pressure of impregnated organic contaminants becomes lower. the removal efficiency becomes poor.

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Organic Pollutant Transport in Unsaturated Porous Media by Atmospheric Breathing Processes( I ) - Partition Coefficient -

  • Ja-Kong;Lim, Jae-Shin;Do, Nam-Young
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1996.11a
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    • pp.50-53
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    • 1996
  • This paper reports the experimental results for the determination of the overall partition coefficient of VOCs in unsaturated soil, A chromatographic method was used for the determination of gaseous partition coefficients to natural soil under various water content conditions. The equilibrium vapor pressure of water over saturated salt solution was used to fix the relative humidity of the air and control the water content of the soil systems. The transport behavior was studied for dichloromethane, trichloroethane and dichlorobenzene pollutants, with log octanol-water partition coefficients(log $K_{ow}$ ) which range from 1.25 to 3.39, or water to soil partitioning which varies by 135 times; water solubility constants which vary by 3 times; and vapor pressures which range from 1 to 362 torr. Water content of the soil had a pronounced effect on the effective partition coefficient(between gas and soil + water stationary phase) as well as on the effective dispersion coefficient.

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Solubilization Isotherms of Chlorobenzene in ionic Surfactant Solutions

  • Baek, Ki-Tae;Yang, Ji-Won
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.201-204
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    • 2003
  • Solubilization isotherms of 1-chlorobenzene (MCB) and 1, 2-dichlorobenzene (DCB) were investigated in ionic surfactant solutions such as sodium dodecyl sulfate (SDS), cetylpyridinium chloride (CPC), and dedecyltrimethylammonium chloride (DMAC). The solubilization extent of DCB was much higher than that of MCB because of the main driving force of solubilization Is hydrophobic interactions between chlorobenzenes and hydrophobic interior of ionic micelles and DCB is more hydrophobic than MCB. CPC showed highest solubilization capacity because of longest hydrophobic tails. Simultaneous solubilization of MCB and DCB decreased slightly the extent solubilization of both MCB and DCB because the solubilization locus in the micelles is same.

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Synthesis of Silver Nanoparticles from the Decomposition of Silver(I) [bis(alkylthio)methylene]malonate Complexes

  • Lee, Euy-Jin;Piao, Longhai;Kim, Jin-Kwon
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.60-64
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    • 2012
  • Silver(I) [bis(alkylthio)methylene]malonates were synthesized from the reaction of silver nitrate and potassium [bis(alkylthio)methylene]malonates. The structures of the Ag complexes were characterized with nuclear magnetic resonance (NMR), inductively coupled plasma atomic emission spectrometry (ICP-AES) and elemental analysis. Ag nanoparticles (NPs) were obtained from the decomposition of the Ag complexes in 1,2-dichlorobenzene at $110^{\circ}C$ without an additional surfactant. The average sizes of the Ag NPs are in the range of 5.1-6.3 nm and could be controlled by varying the length of the alkyl chain. The optical properties, crystalline structure and surface composition of Ag NPs were characterized with ultraviolet-visible (UV-visible) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), gas chromatography-mass spectrometry (GC-MS), X-ray Photoelectron Spectroscopy (XPS) and thermal gravimetric analysis (TGA).

Regioselective Synthesis of 1,3,4,5-Tetrasubstituted Pyrazoles from α-Alkenyl-α,β-Enones Derived from Morita-Baylis-Hillman Adducts

  • Kim, Sung Hwan;Lim, Jin Woo;Yu, Jin;Kim, Jae Nyoung
    • Bulletin of the Korean Chemical Society
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    • v.34 no.10
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    • pp.2915-2920
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    • 2013
  • Convenient synthetic method for 4-arylethylpyrazoles and 4-styrylpyrazoles was developed using ${\alpha}$-alkenyl-${\alpha},{\beta}$-enones readily accessed from the Morita-Baylis-Hillman reaction. For the synthesis of 4-arylethylpyrazole, the reactions with arylhydrazines needed to be carried out in o-dichlorobenzene under $N_2$ balloon atmosphere. On the other hand, 4-styrylpyrazoles required the reactions in ethanol under $O_2$ balloon atmosphere.

Preparation and Photochemical Properties of Zn0.95Mn0.05 (Zn0.95Mn0.05의 제조 및 광화학적 특성)

  • Jung, Dong-woon
    • Journal of the Korean Chemical Society
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    • v.53 no.5
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    • pp.560-564
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    • 2009
  • ZnO and Mn-substituted $Zn_{0.95}Mn_{0.05}O$ were synthesized by using precipitation method. $Zn_{0.95}Mn_{0.05}O$ compound absorbed UV light as well as hole range of visible light ($400{\sim}800$ nm). Results obtained revealed that $Zn_{0.95}Mn_{0.05}O$ showed higher activity than P-25 for visible-photocatalytic degradation of 1,4- dichlorobenzene.