• Title/Summary/Keyword: chemical compounds

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Regeneration of Carbonyl Compounds from Their Nitrogenous Derivatives: Chemical Transformation of the Dicarbonyl Compounds

  • Kim Jae Nyoung;Ryu Eung K.
    • Bulletin of the Korean Chemical Society
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    • v.13 no.2
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    • pp.184-187
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    • 1992
  • Regeneration methods of oximes, hydrazones, and N,N-dimethylhydrazones to the related carbonyl compounds were effected using various dicarbonyl compounds which are activated with electron withdrawing substituents such as trifluoromethylated $\beta-diketones$, $\beta-acylpyruvates$, and $\alpha-diketones$ via an equilibrium exchange reaction. The chemical transformations of the dicarbonyl compounds in the exchange reaction were investigated by various spectroscopic methods.

Comparison of chemical compounds of medicinal plant materials with compounds of domestic pharmacopoeias (식물 약재 구성성분과 국내 약전 성분과의 비교 연구)

  • Kim, Sang-Kyun;Lee, Seungho;Kim, Anna
    • The Korea Journal of Herbology
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    • v.31 no.5
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    • pp.55-62
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    • 2016
  • Objective : TM-MC was constructed to provide information on the chemical compounds of medicinal plant materials which were listed in Korean, Chinese, and Japanese pharmacopoeias. The aim of this study was to compare of the chemical compounds of TM-MC with those of domestic pharmacopoeias.Methods : First of all, TM-MC was updated on medicinal materials and chemical compounds which were extracted from articles up to the PubMed identifier of 26 millions. After searching for medicinal plant materials with information on their major compounds in Korean pharmacopoeias, we identified that the information on medicinal materials and chemical compounds were also existed in TM-MC. Then, we figured out how much the compounds have been studied by counting the number of articles for those compounds in TM-MC.Results : Information on 9 medicinal materials and about 1,700 compounds was newly added to TM-MC after manually curating 645 articles. Korean pharmacopoeias contained a total of 91compounds from 53 medicinal plant materials, while TM-MC provided information on the 89 compounds from the 53 medicinal materials in Korean pharmacopoeias. The compounds stated in Korean pharmacopoeias has been much studied by comparison with other compounds of each medicinal material in TM-MC.Conclusion : Most of chemical compounds stated in Korean pharmacopoeias were also listed in TM-MC, excluding two compounds. Thus, we concluded that information in TM-MC is mostly consistent with that of Korean pharmacopoeias. In the future, we will periodically update TM-MC with articles added to the MEDLINE.

Preparation of Copper Nanoparticles and Catalytic Properties for the Reduction of Aromatic Nitro Compounds

  • Duan, Zhongyu;Ma, Guoli;Zhang, Wenjun
    • Bulletin of the Korean Chemical Society
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    • v.33 no.12
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    • pp.4003-4006
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    • 2012
  • A novel copper nanoparticles were synthesized from cupric sulfate using hydrazine as reducing reagents. A series of aromatic nitro compounds were reacted with sodium borohydride in the presence of the copper nanoparticles catalysts to afford the aromatic amino compounds in high yields. Additionally, the catalysts system can be recycled and maintain a high catalytic effect in the reduction of aromatic nitro compounds.

Chemical pollution of indoor air in Japan

  • Takehiko, Ogawa
    • Proceedings of the Korean Sanitation Conference
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    • 2000.11b
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    • pp.1-21
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    • 2000
  • Recently, indoor air pollution from chemical compounds has been attracting attention. Sick-house syndrome and hypersensitivity to chemical compounds are also being recognized as health problems. In this presentation, the situation of indoor air pollution by chemical compounds in Japan will be explained.

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Bioelectrochemical Detoxification of Phenolic Compounds during Enzymatic Pre-Treatment of Rice Straw

  • Kondaveeti, Sanath;Pagolu, Raviteja;Patel, Sanjay K.S.;Kumar, Ashok;Bisht, Aarti;Das, Devashish;Kalia, Vipin Chandra;Kim, In-Won;Lee, Jung-Kul
    • Journal of Microbiology and Biotechnology
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    • v.29 no.11
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    • pp.1760-1768
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    • 2019
  • The use of lignocellulosic biomass such as rice straw can help subsidize the cost of producing value-added chemicals. However, inhibitory compounds, such as phenolics, produced during the pre-treatment of biomass, hamper the saccharification process. Laccase and electrochemical stimuli are both well known to reduce phenolic compounds. Therefore, in this study, we implemented a bioelectrochemical detoxification system (BEDS), a consolidated electrochemical and enzymatic process involving laccase, to enhance the detoxification of phenolics, and thus achieve a higher saccharification efficiency. Saccharification of pretreated rice straw using BEDS at 1.5 V showed 90% phenolic reduction (Phr), thereby resulting in a maximum saccharification yield of 85%. In addition, the specific power consumption when using BEDS (2.2 W/Kg Phr) was noted to be 24% lower than by the electrochemical process alone (2.89 W/kg Phr). To the best of our knowledge, this is the first study to implement BEDS for reduction of phenolic compounds in pretreated biomass.

Characterization of Basic Nitrogen-Containing Compounds in the Products of Lube Base Oil Processing by Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

  • Li, Xiaohui;Zhu, Jianhua;Wu, Bencheng
    • Bulletin of the Korean Chemical Society
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    • v.35 no.1
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    • pp.165-172
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    • 2014
  • The distribution of basic nitrogen-containing compounds in three vacuum gas oils (VGOs) with different boiling ranges and their dewaxed oils from the lube base oil refining unit of a refinery were characterized by positive-ion electrospray ionization (ESI) Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS). It turned out that the composition of basic nitrogen compounds in the samples varied significantly in DBE and carbon number, and the dominant basic N-containing compounds in these oil samples were N1 class species. $N_1O_1$, $N_1O_2$, and $N_2$ class species with much lower relative abundance were also identified. The composition of basic nitrogen compounds in VGOs and dewaxed VGOs were correlated with increased boiling point and varied in DBE and carbon numbers. The comparison of the analytical results between VGOs and dewaxed VGOs indicated that more basic N-containing compounds in VGO with low carbon number and small molecular weight tend to be removed by solvent refining in lube base oil processing.

Preparation and Properties of New Metal-chain Compounds with Commensurate Peierls Structure

  • Lee, Kuk-Haeng;Kim, Ja-Hong;Mizuno, Masagi
    • Bulletin of the Korean Chemical Society
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    • v.8 no.3
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    • pp.137-140
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    • 1987
  • New platinum chain compounds, $[M(en)_2]_{0.80}[Pt(ox)_2]{\cdot}2H_2O$ where M = Cu or Pt, en = ethylenediamine and ox = oxalate, have been prepared and found to have a commensurate Peierls structure as evidenced by the five-fold Pt chain periodicity and unusually low electrical conductivity $(1.5{\times}10^{-5}{\sim}5.7{\times}10^{-3}S/cm)$. Including two other compounds with the Peierls structure, their characteristic features were deduced and explained from the point of view of the band theory.

Study on the of the Correlation between Soil Chemical Properties and Bioactive Compounds of Acer tegmentosum Maxim.

  • Lee, Dong Hwan;Park, Youngki;Hong, Seong Su;Park, Gwang Hun;Kim, Hyun-Jun
    • Korean Journal of Plant Resources
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    • v.34 no.6
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    • pp.566-574
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    • 2021
  • This research was carried out to investigate the correlation between soil chemical properties and bioactive compounds of Acer tegmentosum Maxim. The methods of determining bioactive compounds were determined by high performance liquid chromatography, that contained (-)-gallocatechin (0.04±0.01 ~ 0.43±0.28%), salidroside (0.90±0.06 ~ 3.86±0.59%), tyrosol (0.03±0.00 ~ 0.43±0.00%), (-)-catechin (0.05±0.01 ~ 0.37±0.14%), 6'-O-galloylsalidroside (0.02± 0.01 ~ 0.31±0.06%), (-)-epicatechin-gallate (0.01±0.00 ~ 0.04±0.01%). The soil chemical properties analysis such as soil pH, electric conductivity (EC), organic matter (OM), total nitrogen (TN), available phosphate (Avail. P2O5), exchangeable cation and cation exchange capacity (CEC) were performed following the standard manual. The correlation analysis between soil chemical properties and bioactive compounds of A. tegmentosum, soil pH, available phosphate and exchangeable cation (Ca2+ and Mg2+) were negatively correlated with content of salidroside. On the other hand, soil exchangeable cation (Na+) showed positive correlation with content of salidroside. The results of this study was able to investigate the correlation between soil chemical properties and bioactive compounds of A. tegmentosum.

A Potential Flame-retardant by Intumescence. Melaminium 2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-4-methoxy-sulfates

  • 김진규;조양하;정옥상;손윤수
    • Bulletin of the Korean Chemical Society
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    • v.16 no.1
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    • pp.62-65
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    • 1995
  • New compounds of melaminium 2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-4-methoxy-sulfate have been synthesized and characterized by means of chemical analysis, 1H, 13C, and 31P NMR, and IR spectroscopies. When the compounds are subjected to an open flame, they foam without melting to produce a light char with about 50 times volume of the initial compounds. The evaluation of these flame-retardants proves to be efficient for polypropylene. Thermogravimetric analysis discloses that the compounds are also thermally stable for compounding into polypropylene without decomposition.