• Journal of Environmental Science International
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• v.11 no.9
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• pp.961-969
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• 2002

This study was performed : 1) to establish the experimental analysis conditions for the sorption and desorption of toxic organic contaminants to/from the activated sludge, sediment, and clay, and 2) to determine the sorption and desorption equilibrium coefficients of some representative halogenated aliphatic compounds. Through the preliminary sorption test using Azo dye, a setting of quantitative experimental conditions to determine the sorption and desorption characteristics was decided as follows; equilibration time of 180 minutes, centrifuge for 15 minutes at 5000$\times$g, and 500mg/$\ell$ of TOC concentration. The sorption and desorption characteristics of halogenated aliphatic compounds onto activated sludge, sediment and clay could be described very well using the Freundlich isotherm. The preference of the average sorption capacity of the overall compounds showed in the sequence sediment 0.26mg/g, clay 0.23mg/g, and activated sludge 0.11 mg/g. The desorption rate of the sorbed compounds onto activated sludge, sediment and clay was approximately 89.8%, 35.3%, and 66.4%, respectively.

• Journal of Environmental Science International
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• v.11 no.7
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• pp.737-742
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• 2002

Sorption and desorption is an important phenomenon to determine the fate of halogenated aliphatic hydrocarbons in the aqueous phase. This study was conducted to develope a predictive equation capable of estimating the sorption and desorption potentials of halogenated aliphatic hydrocarbons onto the sludge from activated process, sediment, and clay. It has shown that the sorption and desorption parameters can be accurately estimated using Quantitative Structural Activity Relationship(QSAR) models based on molecular connectivity indexes of test compounds. The QSAR model could be applied to predict the sorption and desorption capacity of the other halogenated aliphatic hydrocarbons. The QSAR modeling would provide a useful tool to predict the sorption and desorption capacity without time-consuming experiments.

• Korean Journal of Pharmacognosy
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• v.40 no.4
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• pp.326-333
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• 2009

Fourteen compounds were isolated from the 70% ethanol extract of Lonicera Caulis (Caprifoliaceae) and their structures were identified as seven aliphatic compounds [long-chain alcohols (1, 2), trilinolein (3), hexacosanol (4), fatty acids (6), 9,12,13-trihydroxyoctadeca-10(E),15(Z)-dienoic acid (10), and pinellic acid (11)] and seven phenolics [bis(2-ethylhexyl) phthalate (dioctylphthalate, DOP) (5), coniferaldehyde (7), caffeic acid docosanoyl ester (8), caffeic acid (9), coniferyl aldehyde 4-O-glucoside (12), linarin (13), and coniferin (14)]. The chemical structures of these compounds were identified on the basis of spectroscopic methods and comparison with literature values. All the compounds except for caffeic acid (9) were isolated from this plant parts for the first time.

• Journal of the Korean Chemical Society
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• v.47 no.2
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• pp.89-95
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• 2003

We present improved correlations between theoretical and experimental determination of heat of formation of some aliphatic nitro compounds. The method is based on a previously given theoretical procedure, which is ameliorate through the introduction of suitable bond parameters. The comparison with available experimental data and previous theoretical estimation show a quite satisfactory improvement. Some possible further extensions are pointed out.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.287-294
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• 2013

This study was investigated the chemical composition from Syneilesis palmata essential oil and the tendency of variation of the sesquiterpene compounds according to the harvesting time. The essential oils obtained by hydro distillation from the aerial parts of Syneilesis palmata were analyzed by GC and GC-MS. Ninety-eight compounds consisting of 9 aliphatic hydrocarbons, 17 sesquiterpene hydrocarbons, 11 aliphatic aldehydes, 1 terpene aldehyde, 8 aliphatic alcohols, 4 monoterpene alcohols, 16 sesquiterpene alcohols, 3 diterpene alcohols, 6 ketones, 11 esters, 8 oxides and epoxides, 3 acids and 1 miscellaneous one were identified from the oil. Spathulenol (22.33%) was the most abundant compound, followed by ${\beta}$- caryophyllene (6.23%), germacrene D (5.57%), longipinane (4.10%), and epiglobulol (3.65%). The volatile composition of Syneilesis palmata was characterized by higher contents of sesquiterpene compounds, especially sesquiterpene alcohols. The total content of 13 sesquiterpene compounds was decreased significantly from 2010 to 2012. ${\alpha}$-Caryophyllene, ${\beta}$-bisabolene, elemol, germacrene D, ${\beta}$-zingiberene, longipinane, and ${\beta}$-caryophyllene alcohol contents decreased, while ${\beta}$-bisabolol content increased during 3 years. The ecological responses to recent climate change may be influenced in the chemical components of natural plant terpenoids.

• Korean Journal of Materials Research
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• v.30 no.10
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• pp.515-521
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• 2020

Organic-inorganic hybrid perovskite nanocrystals have attracted a lot of attention owing to their excellent optical properties such as high absorption coefficient, high diffusion length, and photoluminescence quantum yield in optoelectronic applications. Despite the many advantages of optoelectronic materials, understanding on how these materials interact with their environments is still lacking. In this study, the fluorescence properties of methylammonium lead bromide (CH₃NH₃PbBr₃, MAPbBr₃) nanoparticles are investigated for the detection of volatile organic compounds (VOCs) and aliphatic amines (monoethylamine, diethylamine, and trimethylamine). In particular, colloidal MAPbBr₃ nanoparticles demonstrate a high selectivity in response to diethylamine, in which a significant photoluminescence (PL) quenching (~ 100 %) is observed at a concentration of 100 ppm. This selectivity to the aliphatic amines may originate from the relative size of the amine molecules that must be accommodated in the perovskite crystals structure with a narrow range of tolerance factor. Sensitive PL response of MAPbBr₃ nanocrystals suggests a simple and effective strategy for colorimetric and fluorescence sensing of aliphatic amines in organic solution phase.

• Membrane and Water Treatment
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• v.5 no.3
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• pp.171-182
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• 2014

Organic compounds are adsorbed on RO/NF membranes, and the adsorption may influence the rejection of organic compounds by the membranes. Because almost RO/NF membranes are composite membranes, the results obtained by adsorption experiment with using membrane pieces are unable to avoid the influence by the support membrane. In this work, the interaction between membrane polymer and organic solutes was examined by an inverse HPLC methodology. Poly (m-phenylenetrimesoylate), the constituent of skin layer of RO/NF membranes, was coated on silica gel particles and used as a stationary phase for HPLC. When water was used as a mobile phase, almost hydrophilic aliphatic compounds were not effectively adsorbed on the stationary phase, although hydrophobic compounds were slightly adsorbed. The results indicated that the hydrophilic aliphatic compounds are useful probe solutes to examine the molecular sieving effect of a membrane. When water was used as a mobile phase, the aromatic compounds were strongly retained, and therefore $CH_3CN/H_2O$ (30/70) was used as a mobile phase. It was revealed that the adsorption of aromatic compounds was controlled by stacking between solute and polymer and was hindered by non-planar structure and substituents.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.118-121
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• 2001

The predictive screening of various molecular descriptors for predicting carcinogenic, mutagenic, teratogenic and alkylation activity of chlorinated disinfection byproducts (DBPs) has been investigated for the application of quantitative structure-activity relationships (QSAR). The toxicity index for 29 compounds were computed by the PASS program and active values were employed in this study. Studies show that different descriptors account for the model equation of each genotoxic endpoint and that thermodynamic descriptors significantly played a major role on prediction of endpoints of chlorinated aliphatic compounds.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.1
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• pp.8-16
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• 1980

The cavity of triple filter was filled with the mixture of clinoptilolite and charcoal(1:1, V/V). The particle size of clinoptilolite was 30$\pm$5 A.S.T.M mesh. The reduction effects of the important gaseous components by this mixture were obtained as follows: 1) In comparison with the normal cellulose acetate niter, the contents of nicotine and T.P.M. were reduced about 35% and 22% respectively. 2) Many aliphatic and cyclic compounds were also substantially reduced in an average of 60%. 3) In contrast with the charcoal, the removal efficiency of clinoptilolite was revealed as higher (15-20%) in case of aliphatic compounds than the one (10-15%) of cyclic compounds. The above results showed us that the removal function of gaseous components was quite complementary each other (charcoal and clinoptilolite).

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.506-512
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• 2007

Various long chain aliphatic acid hydrazides react with aromatic and heterocyclic aldehydes in alcoholic medium in refluxing conditions to give corresponding 2-hydroxy benzylidene and 1H-indol-3-ylmethylene hydrazides, a newer class of mosquito para-pheromones. We describe here synthesis of various novel long chain aliphatic acid (2- hydroxy benzylidene and 1H-indol-3-ylmethylene) hydrazides by conventional as well as microwave irradiation techniques. The structures of these compounds have been confirmed by spectroscopic techniques (FTIR, NMR & MS). Some of the interesting features of the electron impact mass spectral fragmentation pattern of these compounds have also been discussed.