• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3645-3650
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• 2012

Two new blue emitting cationic iridium(III) complexes with two substituted 2-phenlypyridine ligands as main ligands and one 2,2'-biimidazole as an ancillary ligand, $[(L1)_2Ir(biim)]Cl$ (1) and $[(L2)_2Ir(biim)]Cl$ (2), where L1 = 2-(2',4'-difluorophenyl)-4-methylpyridine, L2 = 2-(2',4'-difluoro-3'-trifluoromethylphenyl)-4-methylpyridine and biim = 2,2'-biimidazole, were synthesized for applications in phosphorescent organic light-emitting diodes (PhOLEDs). Their photophysical, electrochemical and electroluminescent (EL) device performances were examined. The photoluminescent (PL) spectra revealed blue phosphorescence in the 450 to 485 nm range with a quantum yield of more than 10%. The iridium(III) compounds studied showed good solubility in organic solvents with no solvatochromism dependent on the solvent polarity. The solution-processed OLEDs were prepared with the configuration, ITO/PEDOT:PSS (40 nm)/mCP:Ir(III) (70 nm)/OXD-7 (20 nm)/LiF (1 nm)/Al (100 nm), by spin coating the emitting layer containing the mCP host doped with the iridium phosphors. The best performance of the fabricated OLEDs based on compound 1 showed an external quantum efficiency of 4.5%, luminance efficiency of 8.52 cd $A^{-1}$ and blue emission with the CIE coordinates (x,y) of (0.16, 0.33).

• 한국식품영양과학회지
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• 제29권2호
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• pp.211-217
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• 2000

To standardize quality characteristics of commercial doenjang prepared by traditional method, general components, organic acids, amino acids and fatty acid composition were investigated. Moisture, crude protein, crude lipid, titratable acidity (expressed as milliliter of 0.1 N NaOH), acid value and salinity were 54.7%, 13.8%, 8.0%, 14.4mL, 45.7mg/g and 11.8%, respectively. The content of amino type nitrogen was 345.3mg% (w/w) in the range of 207.6 to 443.5mg% being 1.1~2.2-fold for all samples. Average value of Hunter color for L(lightness), a(redness) and b(yellowness) were 37.4, ＋9.7 and ＋21.3, respectively. Browning index value(expressed as optical density at 425 nm) of water-soluble compound(2.58) was above 7.1 times higher than that of the water-insoluble compound(0.38). Total contents of free and total amino acid were 3.81 and 9.72%, respectively, and then the former(1.1~3.7 times) was more different in all samples tested than that of the latter(1.1~2.0 times). Among amino acids, glutamic acid was abundant and its content of free and total amino acids was 0.57 and 1.24%, respectively. Of organic acids, lactic acid was the most abundant being 0.34%(average) and ranged from 0.15 to 0.86%. Linoleic acid(52.17%, as area%) was the highest content of the total fatty acids. Unsaturated and polyunsaturated fatty acids were 83.89 and 61.189%, respectively. Polyunsaturated fatty acid was markedly different among all samples and ranged from 51.52 to 64.91%.

• Journal of Ecology and Environment
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• 제46권1호
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• pp.62-75
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• 2022

Background: Pollinators help plants to reproduce and support economically valuable food for humans and entire ecosystems. However, declines of pollinators along with population growth and increasing agricultural activities hamper this mutual interaction. Nectar and pollen are the major reward for pollinators and flower morphology and volatiles mediate the specialized plant-pollinator interactions. Limited information is available on the volatile profiles attractive to honey bees and bumblebees. In this study we analyzed the volatile organic compounds of the flowers of 9 different plant species that are predominantly visited by honey bees and bumblebees. The chemical compositions of the volatiles were determined using a head space gas chromatography-mass spectrometry (GC-MS) method, designed to understand the plant-pollinator chemical interaction. Results: Results showed the monoterpene 1,3,6-octatriene, 3,7-dimethyl-, (E) (E-𝞫-ocimene) was the dominating compound in most flowers analyzed, e.g., in proportion of 60.3% in Lonicera japonica, 48.8% in Diospyros lotus, 38.4% Amorpha fruticosa and 23.7% in Robinia pseudoacacia. Ailanthus altissima exhibited other monoterpenes such as 3,7-dimethyl-1,6-octadien-3-ol (𝞫-linalool) (39.1%) and (5E)-3,5-dimethylocta-1,5,7-trien-3-ol (hotrienol) (32.1%) as predominant compounds. Nitrogen containing volatile organic compounds (VOCs) were occurring principally in Corydalis speciosa; 1H-pyrrole, 2,3-dimethyl- (50.0%) and pyrimidine, 2-methyl- (40.2%), and in Diospyros kaki; 1-triazene, 3,3-dimethyl-1-phenyl (40.5%). Ligustrum obtusifolium flower scent contains isopropoxycarbamic acid, ethyl ester (21.1%) and n-octane (13.4%) as major compounds. In Castanea crenata the preeminent compound is 1-phenylethanone (acetophenone) (46.7%). Conclusions: Olfactory cues are important for pollinators to locate their floral resources. Based on our results we conclude monoterpenes might be used as major chemical mediators attractive to both honey bees and bumblebees to their host flowers. However, the mode of action of these chemicals and possible synergistic effects for olfaction need further investigation.

• 한국유기농업학회지
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• 제23권3호
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• pp.535-547
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• 2015

본 연구는 베리와 그 부산물들의 영양학적 가치와 더불어 이들의 식품 내 활용 가능성을 확인하고자 국내생산 베리 중 대표적 베리인 블루베리, 오디 그리고 복분자와 그들 부산물의 이화학적 특성과 페놀화합물 함량변화를 비교/분석하였다. 수분함량은 통 베리 시료가 그들 부산물의 함량보다 유의적으로 높게 나타났으며, 특히 복분자와 그 부산물의 수분함량은 차이가 가장 컸다. pH는 오디와 오디 부산물에서 각각 4.03, 5.18로 가장 높게 나타났다. 총 폴리페놀과 플라보노이드의 함량은 블루베리 부산물에서 24.81와 24.13 mg/g으로 가장 높았으며, 안토시아닌 함량은 오디 부산물에서 53.27 ug/g으로 가장 높았다. Cyanin chloride는 오디와 복분자 과일에서만 측정되었으며, epigallocatechin, gallocatechin과 isorhamnetin은 블루베리에서만 측정되었다. Catechin (hydrate)과 epicatechin의 경우에는 블루베리를 제외한 오디와 복분자의 통 과일과 부산물에서 유의적인 차이가 나타났으며, gallic acid는 오디에서, quercetin 3-D-galactoside는 블루베리에서 통 과일과 부산물간 유의적인 차이가 조사되었다. Apigenin, luteolin은 오디류에서만 측정되었으며 특히 부산물에서 그 함량이 높았다. Naringenin은 각각의 베리 부산물에서 함량이 높았으나, rutin (trihydrate)과 quercetin은 블루베리를 제외한 오디와 복분자의 통 베리에서 부산물보다 높게 검출되었다. Kaempferol 함량은 통 오디에서 15 ng/g으로 가장 높았다. 본 실험에 이용된 베리들은 성숙도 및 환경에 따라 서로 다른 결과를 나타날 수도 있겠으나, 본 연구결과는 각각의 통 베리의 유효성분을 조사한 것 뿐 아니라 그들의 부산물까지도 가축 사료 첨가제 및 식품 소재로써 활용 가능성을 나타낸 연구라 할 수 있다.

• 농약과학회지
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• 제14권3호
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• pp.199-208
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• 2010

Phenylformamidine계 유도체들은 곤충의 신경전달 물질인 octopamine과 경쟁적으로 octopamine receptor에 작용하여 생육 전 단계에 걸쳐 살충 활성을 나타내는 젓으로 알려져 있다. 본 연구에서는 고활성 화합물을 발견하기 위해 과거에 합성되지 않은 불소를 함유한 phenylformamidine 유도체에 N-dialkylaminosulfenyl 치환체를 도입하여 새로운 화합물을 합성하고 살충활성 시험을 한 결과 N-(dialkylamino)sulfenyl-N-methyl-N'-(4-fluoro-2-methyl-phenyl)formamidines 유도체들이 높은 살충 활성 나타내었으며 특히, 이들 중 가장 우수한 살충 활성을 갖는 화합물 29와 대조약제인 Amitraz의 점박이응애에 대한 $LD_{90}$는 각각 32.0 ppm, 150.4 ppm으로 화합물 29는 점박이응애에 대하여 Amitraz보다 5배 우수한 살충활성을 나타내었다.

• Safety and Health at Work
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• 제10권2호
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• pp.229-236
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• 2019

Background: Emerging reports suggest the potential for adverse health effects from exposure to emissions from some additive manufacturing (AM) processes. There is a paucity of real-world data on emissions from AM machines in industrial workplaces and personal exposures among AM operators. Methods: Airborne particle and organic chemical emissions and personal exposures were characterized using real-time and time-integrated sampling techniques in four manufacturing facilities using industrial-scale material extrusion and material jetting AM processes. Results: Using a condensation nuclei counter, number-based particle emission rates (ERs) (number/min) from material extrusion AM machines ranged from $4.1{\times}10^{10}$ (Ultem filament) to $2.2{\times}10^{11}$ [acrylonitrile butadiene styrene and polycarbonate filaments). For these same machines, total volatile organic compound ERs (${\mu}g/min$) ranged from $1.9{\times}10^4$ (acrylonitrile butadiene styrene and polycarbonate) to $9.4{\times}10^4$ (Ultem). For the material jetting machines, the number-based particle ER was higher when the lid was open ($2.3{\times}10^{10}number/min$) than when the lid was closed ($1.5-5.5{\times}10^9number/min$); total volatile organic compound ERs were similar regardless of the lid position. Low levels of acetone, benzene, toluene, and m,p-xylene were common to both AM processes. Carbonyl compounds were detected; however, none were specifically attributed to the AM processes. Personal exposures to metals (aluminum and iron) and eight volatile organic compounds were all below National Institute for Occupational Safety and Health (NIOSH)-recommended exposure levels. Conclusion: Industrial-scale AM machines using thermoplastics and resins released particles and organic vapors into workplace air. More research is needed to understand factors influencing real-world industrial-scale AM process emissions and exposures.

• 한국대기환경학회지
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• 제25권5호
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• pp.420-431
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• 2009

Characteristics and advantages of the thermal desorption-comprehensive two dimensional gas chromatography-time of flight mass spectrometry (TD-GCxGC-TOFMS) were discussed and the organic compound's analysis result was shown for the ambient $PM_{2.5}$ sample collected in Seoul, Korea. Over 10,000 individual organic compounds were separated from about $70{\mu}g$ of aerosols in a single procedure with no sample pre-treatment. Among them, around 300 compounds were identified and classified based on the mass fragmentation patterns and GCxGC retention times. Several aliphatic compounds groups such as alkanes, alkenes, cycloalkanes, alkanoic acids, and alkan-2-ones were identified as well as 72 PAH compounds including alkyl substituted compounds and 8 hopanes. In Seoul aerosol, numerous oxidized aromatic compounds including major components of secondary organic aerosols were observed. The inventory of organic compounds in $PM_{2.5}$ of Seoul, Korea suggested that organic aerosol were constituted by the compounds of primary source emission as well as the formation of secondary organic aerosols.

• 농약과학회지
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• 제12권2호
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• pp.201-205
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• 2008

환경친화형 신규 고활성 토양처리 제초제 개발 연구의 일환으로 하이드록시 알킬 치환체를 갖는 테트라하이드로인 다졸계 protoporphyrinogen IX oxidase 저해 화합물 $6a{\sim}6h$들을 합성하였으며, 온실에서 밭조건 토양처리 제초활성 시험을 실시하였다. 합성된 화합물중에서 트리메틸 하이드록시 알킬 치환체를 갖는 화합물 6f의 제초활성이 우수하였으며, 다양한 작물 선택성을 갖고 있었다.

• 한국환경과학회지
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• 제31권12호
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• pp.1127-1134
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• 2022

Herein , the effect of changes in the organic loading rate in anaerobic digestion was evaluated. The experiment was carried out by a laboratory -scale semi-continuous stirred tank reactor, and feedstock was food-waste leached. The organic loading rate was increased by 0.5 kgVS/m3 in each phase from 1.0 kgVS/m3 to 4.0 kgVS/m3. At the end of the operation, to check the failure of the reactor, the organic loading rate was increased by 1.0 kgVS/m3 in each phase and reached 6.0 kgVS/m3. This shows that the biogas yield decreased as organic loading rate increased. Biogas production seemed to be unstable at 3.5-6.0 kgVS/m3. Moreover, biogas production dramatically fell to approximately 0 mL at 6.0 kgVS/m3, which was decided as the operation failure on the 16th day of the las tphase. The result of the reactor analysis shows that the cumulation of volatile fatty acid increased as the organic loading rate increased. This seems to occur due to the decreasein pH in the reactor and led to extinction of anaerobic bacteria, which were the biogas products. Although the buffer compound (alkalinity) could prevent the decline in pH, the concentration of alkalinity was found to be lacking at a high organic loading rate

• 한국대기환경학회지
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• 제31권5호
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• pp.482-492
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• 2015

Ground-based measurements were conducted from January 6 to 12 of 2015 for understanding characteristics of nitrogen containing carbonaceous aerosols as 16 amino acids at the Mokpo National University, Korea. The detailed amino acid components such as Cystine ($(SCH_2CH(NH_2)CO_2H)_2$) and Methionine ($C_5H_{11}NO_2S$) and their sources were analyzed by High-Performance Liquid Chromatography with Fluorescence Detection (HPLC-FLD) for behavior of secondary products in particulate matter. In addition, organic carbon (OC) and elemental carbon (EC) based on the carbonaceous thermal distribution (CTD), which provides detailed carbon signature characteristics relative to analytical temperature, and water soluble organic carbon (WSOC) by total organic carbon (TOC) analyzer were used to understand the carbon compound behaviors. The backward trajectories were discussed for originations of carbonaceous aerosols as well. Different airmasses were classified with the amino acids and OC thermal signatures. The results can provide to understand the aging process influenced by the long-range transport from East Sea area.