• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1105-1109
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• 1998

A chiral stationary phase derived from (S)-N-(3,5-dinitrobenzoyl)leucine N-phenyl N-alkyl amide (CSP 2) was applied in separating the two enantiomers of various π-basic aromatic derivatives of leucine N-propyl amide in order to evaluate π-basic aromatic groups as an effective derivatizing group for the resolution of a-amino acids. Subsequently N-(3,5-dimethoxybenzoyl) group was found to be very effective as a π-basic aromatic derivatizing group. Based on these results, N-(3,5-dimethoxybenzoyl) derivatives of various a-amino N-propyl amides, N,N-diethyl amides and esters were resolved on the CSP derived from (S)-N-(3,5-dinitrobenzoyl) leucine N-phenyl N-alkyl amide (CSP 2) and the resolution results were compared with those on the CSP derived from (S)-N-(3,5-dinitrobenzoyl)leucine N-alkyl amide (CSP 1). The enantioselectivities exerted by CSP 2 were much greater than those exerted by CSP 1. In addition, racemic N-(3,5-dimethoxybenzoyl)-a-mino N,Ndiethyl amides were resolved much better than the corresponding N-(3,5-dimethoxybenzoyl)-a-mino N-propyl amides and esters on both CSPs. Based on these results, a chiral recognition mechanism utilizing the π-π donor-acceptor interaction and the two hydrogen bondings between the CSP and the analyte was proposed.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.373-379
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• 2018

A transparent, freestanding Porous Aromatic Framework-97 (PAF-97) membrane was successfully synthesized via a one-step acid-catalyzed reaction. Due to the introduction of ether groups, the obtained PAF-97 membrane possesses enhanced structural flexibility, thus increasing the flexibility of the resulting membrane. This is proofed by the fact that the feeding pressure of the membrane reaches as high as 5.5 bar during the separation of gas mixtures. The Young's moduli of the membrane were 6.615 GPa and 11.11 GPa, either in a dry or hydrated state respectively. To be highlighted, under a feeding pressure of 3.6 bar, the PAF-97 membrane rendered the permeance values of $2.90{\times}10^{-7}$, $1.29{\times}10^{-8}mol\;m^{-2}s^{-1}Pa^{-1}$ for $CO_2$ and $CH_4$, respectively, with a $CO_2/CH_4$ permselectivity of 22.48.

• Mass Spectrometry Letters
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• v.13 no.4
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• pp.125-132
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• 2022

There are many types of spring blossoms on the Daedeok campus of Chungnam National University (CNU) at the area of 1,600,000 square meters. As an assignment for the class of Analytical Chemistry I for second-year undergraduate students, 2021, flower petals collected from various floral groups (Korean azalea, Korean forsythia, Dilatata lilac, Lilytree, Lily magnolia, and Prunus yedoensis) were analyzed using headspace extraction coupled to gas chromatography-mass spectrometry (HS-GC-MS) to study the aromatic profiles and fragrance compounds of each sample group. Various types of compounds associated with the aroma profiles were detected, including saturated alcohols and aldehydes (ethanol, 1-hexanol, and nonanal), terpenes (limonene, pinene, and ocimene), and aromatic compounds (benzyl alcohol, benzaldehyde). The different contribution of these compounds for each floral type was visualized using statistical tools and classification models based on principal component analysis with high reliability (R² = 0.824, Q² = 0.616). These results showed that HS-GC-MS with statistical analysis is a powerful method to characterize the volatile aromatic profile of biological specimens.

• Journal of Environmental Science International
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• v.33 no.1
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• pp.59-65
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• 2024

The objective of this study were to assess rooftop urban agriculture and analyze the differences in soil, growth, physiology, and productivity to elucidate the effect of companion planting with various plants, including lettuce (Lactuca sativa), rosemary (Salvia rosmarinus), marigold (Tagetes patula), Korean perilla (Perilla frutescens), and garlic chives (Allium senescens). Measurements were taken every other week from May to August 2023, totaling eight measurement. Regarding the characteristics of the soil planted with lettuce and aromatic plants, the combined planting of lettuce and garlic chives created a favorable soil environment for plant growth. Consequently, the best growth was observed when lettuce and garlic chives were companion planted. Companion planting of lettuce and garlic chives appears to be the most efficient concerning growth and physiology. The productivity of companion planting lettuce and aromatic plants also showed high-quality lettuce when lettuces and garlic chives were companion planted. Therefore, companion planting of lettuces and garlic chives in rooftop urban agriculture is suitable for growth, physiology, and productivity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.496-504
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• 1996

The study was conducted to obtain the basic information on increasing aromatic degrees by shading and organic matter application on Condonopsis lanceolata. The result were as followings : Fresh root wt. in shading 55 % treatment was increased about twices, whereas fresh root weight in non-shading was decreased. But growth of ground parts such as vine length, leaf width, and leaf number was promoted under non-shading treatment. Macroelements such as K, Ca, and Mg, were increased in non-shading and higher organic matter application. The components such as crude protein, fiber, and ash were increased in the shading 55% treatment compared with non-shading. In the sixteen amino acids, arginine contents were the highest in non-shading and organic matter 30M/T. Recovery yield of essential oil was 0.005% in non-shading. The highest was organic matter 30M/T in the non-shading as 0.007%. Major aromatic constituents were 11 kinds of aliphatic alcohols such as I-hexanol, cis-3-hexenol, and trans-2-hexanal. As a result, major aromatic degree was higher in shading 55%, also increased in the much organic matter application. It was considered to be applied dense shading 55% and much organic matters to produce Condonopsis lanceolata plants which have high aroma and good quality.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.799-805
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• 2000

In order to manufacture the high-quality products as well as to promote their consumption, dry noodles were prepared with Korean wheat flour and brown glutinous rice flour with and without aroma and quality characteristics of dry noodles were investigated. The average particle size distributions of aromatic brown glutinous rice flour and brown glutinous rice flour ranged from 12.38 to $15.59\;{\mu}m$, which was different from that of control. As a result of farinograph study, water absorption of dough increased and decreased with increasing amounts of brown glutinous rice flour with and without aroma, respectively. Stability, developing time and elasticity of dough showed a decreasing tendency. When compared with the control, aromatic brown glutinous rice samples produced noodles with a greater degree of lightness and a less intensity of yellowing. Replacement of up to 20% of Korean wheat flour by aromatic brown glutinous rice flour and brown glutinous rice flour in noodle had similar cooked properties such as weight gain, volume and water absorption as compared with the control. From the result of sensory evaluation, composite flours(addition up to 30% aromatic brown glutinous rice flour and up to 20% brown glutinous rice flour) and control were rated with a relatively high quality score for appearance, taste and overall eating quality.

• Journal of Photoscience
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• v.11 no.32
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• pp.71-74
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• 2004

The macrocycle L exhibited a switch on-off behavior through the fluorescent responses by aromatic imine molecule 1 (X=H) / trifluoroacetic acid (TFA). In the 'switch on' state, it was supposed that the aromatic imine molecule 1 is in the cavity of macrocycle L and a photoinduced electron transfer (PET) from the nitrogen of azacrown part to the anthryl group is inhibited by the interaction between the aromatic imine molecule 1 and the azacrown part of macrocycle L. In the 'switch off' state, it was supposed that the protonated imine molecule 1 is induced by the continuous addition of TFA and a repulsion between the protonated azacrown part and the protonated imine molecule 1 is occurred. It was considered that this process induces the intermolecular PET from the protonated imine molecule 1 to the anthryl group of macrocycle L because of a proximity effect between the anthryl group and the protonated imine molecule 1. From the investigation of the transient emission decay curve, the macrocycle L showed three components (3.45 ns (79.72%), 0.61 ns (14.53%), and 0.10 ns (5.75%). When the imine molecule 1 was added in the macrocycle L as molar ratio=1:1, the first main component showed a little longer lifetime as 3.68 ns (82.75%) although the other two components were similar as 0.64 ns (14.28%) and 0.08 ns (2.96%). On the contrary, when the imine molecule 3 (X=C1) was added in the macrocycle L as molar ratio=l:1, all the three components were decreased such as 3.27 ns (69.83%), 0.44 ns (13.24%), and 0.06 ns (16.93%). The fluorescent pH titration of macrocycle L was carried out from pH=3 to pH=9. The macrocycle L and C $U^{2+}$- macrocycle L complex were intersected at about pH=5, while the E $u^{3+}$ -macrocycle L complex was intersected at about pH=5.5. In addtion, we investigated the fluorescence change of macrocycle L as a function of the substituent constant ($\sigma$$_{p}$$^{o}$) showing in the para-substituent with electron withdrawing groups (X=F, Cl) and electron donating groups (X=C $H_3$, OC $H_3$, N(C $H_3$)$_2$), respectively, as well as non-substituent (X=H).).ctively, as well as non-substituent (X=H).

• Journal of Korean Society of Forest Science
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• v.65 no.1
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• pp.31-42
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• 1984

This study contains the scientific justification of the forest aromatic bath(F.A.B) in the stage of introduction and the general concepts using in the design of the forest aromatic bath ground, especially definition of F.A.B, basic activities and facilities, carrying capacity and criteria deserving much consideration in designing of it. Terpene, the origin of F.A.B appearance, is made clear that it is efficacious in our physical health. The forest (coniferous one) mainly exhales terpene about noon and morning and seasonally spring and summer time. The most influential factor to exhale terpene is the climate one-wind, temperature, sunlight, humidity. Forest canopy and leaves are related to the concentration of terpene in the forest area. The basic activities for F.A.B are mostly static, and so are the facilities. The forest aromatic bath room(F.A.B.R) which a person must be given for F.A.B. is $169m^2$, 59 persons per ha. This $169m^2$ is the carrying capacity of F.A.B. The sites of F.A.B.G. might better be located around the national and provincial park, mountain torrent, hot spring zone and the waterfronts. Meanwhile, forest management in F.A.B.G should be enforce in order to keep on constantly maintaining the exhalation quantity of terpene.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.239-244
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• 1998

This experiment was to determine the effects of soil pH on crude components and aromatic constituents of Codonopsis lanceolata. Vine length of Codonopsis lanceolata grown at soil pH of 6.5 was longer(299cm) compared to that grown under other soil pHs. Fresh root weight increased at soil pH of 5.5 and 6.5, showing 17.9 and 15.6g per plant, respectively. Contents of crude components such as protein, fat, fiber, and ash decreased as soil became alkalized and crude ash content ranged from 2.99% to 3.85 %, showing a similar response to soil pH. Forty-eight volatile aromatic compounds in the root of Codonopsis lanceolata were identified by GC/MS. Major aromatic compounds were 1-hexanol, cis-3-hexanol, and trans-2-hexanol. In particular, trans-2-hexanol was highest in soil pH of 6.5, attaining the 156.87% area. Essential oil content was also highest at soil pH of 6.5 with 0.007%. As a result, it was considered that the soil pH of 6.5 was most effective for the improvement of essential oil and aromatic constituents in the roots of Condonopsis lanceolata Trautv.

• Journal of Mushroom
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• v.20 no.2
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• pp.86-91
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• 2022

Pleurotus eryngii, a white rot fungus, produces two extracellular lignin-degrading enzymes, laccase and manganese peroxidase (MnP). Owing to these enzymes, P. eryngii efficiently degrades synthetic chemicals such as azo, phthalocyanine, and triphenyl methane dyes. In this study, we investigated the degradation processes of four aromatic dyes, congo red (CR), methylene blue (MB), crystal violet (CV), and malachite green (MG), by P. eryngii under solid and liquid culture conditions. CR and MG were the most quickly degraded under solid and liquid culture conditions, respectively. However, compared to CR, CV, and MG, MB was not degraded well under both culture conditions. The activities of ligninolytic enzymes (laccase and MnP) were also investigated. Laccase was identified to be the major enzyme for dye degradation. A positive relationship between decolorization and enzyme activity was observed for CR, MB, and CV degradation. In contrast, decolorization of MG ensued after high enzyme activity. These results indicate that the degradation process differs between MG and the other aromatic dyes. Therefore, P. eryngii could be a potential tool for the bioremediation of synthetic aromatic dye effluent.