• Journal of Environmental Health Sciences
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• v.18 no.2
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• pp.102-105
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• 1992

Introduction : Isothiazolinone product is one of new preservatives used in cooling tower, paper mill, and general industrial waters.l) It is also effective in controlling bacteria and fungi in the manufacture and storage of dispersed pigments, such as kaolin clays, titanium dioxide, calcium carbonate and others\ulcorner Its broad-spectrum activity, excellent physical and chemical compatibility with anionic, nonionic and cationic surfactants and most organic and inorganic compounds and low toxicity at recommended use levels provide formulators with an effective, economical, and environmentally acceptable alternative to other commercial biocides. It dose not contain or generate formaldehyde and is easy to formulate (1.5% solution is supplied as an aqueous solution), so that it gains advantage over the other preservatives. The active ingredients of the isothiazolinone product are unchlorinated compound (2-methyl-4-isothiazolin-3-one) and chlorinated one (5-chloro-2-methyl-4-isothiazolin-3-one). Methods preferred for the analysis of preservatives are chromatographic methods, especially high performance liquid chromatograph (HPLC). Although several methods were satisfactory in respect to separation, no offical method has been published for the isothiazolinone components. This study was performed to search for an alternative method in order to show flexible operating conditions of HPLC and to reduce assay time.

• Korean Journal of Organic Agriculture
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• v.19 no.1
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• pp.23-38
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• 2011

● The current world is suffering abnormal climate caused by global warming. The main cause of global warming is greenhouse gas such as carbon dioxide. The carbon labeling system and carbon traceability system being pushed ahead in the agricultural sector is the policy for responding to climate change to reduce greenhouse gas emissions. To make this policy more effective and enhanced, the amount of carbon emissions should be calculated based on the kind of crops or the various businesses in the agricultural sector. Therefore, in order to estimate the accurate amount of carbon emissions, it is necessary to establish carbon dioxide emission intensity of various agricultural materials added onto the agriculture, and to calculate the amount of carbon dioxide emission for each crop according to agricultural production. The purpose of this study is to establish the amount of emission, emission per agricultural materials, of agricultural materials being added for crop production as a basic step, and emission intensity which can be used in the future market in order to estimate accurate amount of carbon emission in all the policies being promoted in the agricultural sector. Therefore, in this study, in order to build LCI D/B about organic fertilizers among many organic materials added onto the organic agriculture sector, one leading company in organic fertilizer production was selected and LCA was conducted for this leading company. We had to build the intensity and integrated average concept of intensity upon the two cases once production farmers for their own consumption and farms besides organic fertilizer company were categorized even if it's little amount. But in this study, individually produced organic fertilizers were excluded. Calculated results are following. Carbon emission of mixed expeller cake fertilizer in organic fertilizer was 1,106,966.89kg-$CO^2$ and emission intensity was 0.01606kg-$CO^2$, respectively. Total emission of mixed organic fertilizers was 241,523.2kg-$CO^2$ and emission intensity was 0.01705kg-$CO^2$. And total emission of organic compound fertilizers was 94,592.66kg-$CO^2$ and emission intensity was 0.01769kg-$CO^2$, respectively.

• Journal of Applied Biological Chemistry
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• v.42 no.3
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• pp.146-150
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• 1999

As a part of the integrated disease system in greenhouse, an antifungal fungus(AF1) was isolated from greenhouse soil. It exhibited strong inhibitory activites against Pythium ultimum, Phytophtora capsici, Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum based on dual culture on 1/5 strength of potato dextrose agar between antagonistic fungus and several plant pathogens. The antagonistic fungus was identified as Chaetomium cochliodes, based on morphological characteristics; the body of the perithecium bears straight or slightly wavy, unbranched hairs, whilst the apex bears a group of spirally coiled hairs. To investigate antagonistic principles, antifungal compound was extracted and fractionated by different solvent systems. An antifungal compound was isolated as pure crystal from is culture filtrate using organic solvent extraction and column chromatography, followed by preparative thin layer chromatography. The chemical structure of the purified antifungal compound was identified as chaetoglobosin A based on the data obtained form $^1H-NMR$, $^{13}C-NMR$, DEPT 90, 135, $^1H-^1H$ COSY, $^1H-^{13}C$ COSY and EI/MS. $ED_{50}$ values of the chaetoglobosin A against P. ultimum, P. capsici, R. solani, B. cinerea and F. oxysporum were 1.98, 4.01, 4.16, 2.67 and 35.14 ppm, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.73-74
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• 2022

The corrosion inhibitive effect of a new hydrazone-based heterocyclic compound for steel in simulated concrete pore solution with 3.5 wt.% sodium chloride was investigated by experimental and computational techniques. Electrochemical studies, up to 30 days of immersion, and surface analysis (X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscope (SEM)) were performed to assess the corrosion protection abilities of investigated compound for steel rebar. Results showed that adding the organic compound to the chloride contaminated concrete pore solution decreased the corrosion rate of the steel rebar thanks to the effective adsorption of inhibitor molecules. After 30 days of immersion of steel rebar in inhibited chloride contaminated synthetic concrete pore solution, the inhibition efficiency exceeded 80% at low concentration of 1 mmol/L. Computational studies by Density Functional based Tight Binding (DFTB) method revealed the formation of covalent bonds between the hydrazone molecule and the iron surface.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.51-57
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• 2003

For the purpose of a development of new agrochemical fungicides, new compound 4 in which 1,3-thiazoline scaffold as well as urea moiety in the structure was designed through molecular modification of lead compound, 2-imino-1,3-thiazone based on isosterism. The reaction of N-alkylthiourea 5 and bromoacetonitrile in ethanol gave 2,4-diimino-1,3-thiazolidine hydrobromide 6 regioselectively, which was treated with isocyanates gave the corresponding 8 which is tautomer of 4. Antifungal screening (in vivo) of the synthesized compound 8 against typical plant diseases, which include rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew, was carried out. Antifungal activities against rice blast of the compound 8 were weaker than those of 2-phenylimino-1,3-thiazoline 1. Some compounds showed weak antifungal activities against wheat leaf rust.

• Journal of the Korean Wood Science and Technology
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• v.42 no.6
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• pp.747-757
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• 2014

Since the air contamination by air pollutants from indoor construction materials and daily supplies has been increased in recent decades, the public interest of using environmentally friendly products and improving indoor air quality also attracted much attention. As known as effects of phytoncide, it has been used in construction materials and daily supplies with various method. In this study, hinoki cypress (Chamaecyparis obtusa) was used because of its high contents of phytoncide. The leaves of hinoki cypress (C. obtusa), which generated by pruning, were extracted by steam distillation, and then used as humidification water source. Volatile organic compound (VOC) from C. obtusa were characterized by GC-MS (Gas chromatograph-Mass spectrophotometry) in order to evaluate effects and risks of using C. obtusa extracts. Total 86 types and 116 types of VOC were detected from distilled water (DI water) and C. obtusa extracts, respectively. Aromatic compounds (DI water: 13 types, 53%; C. obtusa extracts: 13 types, 38%) and terpenoids (DI water: 16 types, 23%; C. obtusa extracts: 23 types, 33%) were detected more diverse types and higher amount than other compound categories. No additional aromatic compounds were found from C. obtusa extracts, so C. obtusa extracts did not affect on aromatic compounds emission. However, in terpenoids, total amount of emission from C. obtusa extracts increased to 33% from 23% (DI water) and 7 more types of compounds were found from C. obtusa extracts. Especially, from C. obtusa extracts, terpinen-4-ol was emitted 71 times higher than DI water. During the humidification with C. obtusa extracts, emitted terpenoid compounds were well known for higher anti-bacterial, anti-insect, and anti-septic functions, but also these had anti-hypertensive and anti-cancer activities. Therefore, terpenoids from C. obtusa extracts can help to improve public health by using humidifier.

• Journal of Life Science
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• v.24 no.3
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• pp.234-241
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• 2014

To identify and isolate anticancer active compounds from Solanum nigrum, S. nigrum was extracted with MeOH and then fractionated with various organic solvents ($CH_2Cl_2$, EtOAc, n-BuOH, and $H_2O$). The cytotoxic effects of the MeOH extracts from S. nigrum and its organic solvent-soluble fractions were also tested in HT29 cells. All the MeOH extracts of S. nigrum and its organic-solvent extracts induced cytotoxicity in the HT29 cells. Among the extracts, $H_2O$ was the most effective. The $H_2O$ extract was purified further by repeated silica gel, Sephadex LH-20, Diaion HP- 20, and RP-18 column chromatography. An active anticancer compound, Des-N-26-methylene-dihydrotomatidine, was isolated with a molecular weight of 416 and a molecular formula of $C_{28}H_{48}O_2$. Analysis of the cytotoxic effects of Des-N-26-methylene-dihydrotomatidine on the HT29 cells compared to those of tomatine and tomatidine are similar in its structure, is higher than tomatidine above the 40 ${\mu}g/ml$ concentration, but lower than tomatine. This is the first study to describe the anticancer activity of Des-N-26-methylene-dihydrotomatidin, isolated from S. nigrum. Des-N-26- methylene-dihydrotomatidine seems to have potential as a natural bioactive compound.

• Asian Journal of Atmospheric Environment
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• v.12 no.2
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• pp.127-138
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• 2018

This study measured indoor and outdoor levels of hydrocarbon volatile organic compounds (VOCs), such as benzene, toluene, ethylbenzene, and xylene isomers (collectively referred to as BTEX), as well as 13 carbonyl compounds, at 20 homes in Seoul, South Korea. Along with the sampling of BTEX and carbonyls, indoor concentrations of the air pollutants nitrogen oxide (NO) and carbon dioxide ($CO_2$) were also measured at each home. These measurements were used to understand the characteristics of BTEX and carbonyls by calculating the various ratios and correlation coefficients between measured contaminant levels. We found that carbonyls were mostly originated from indoor sources, while BTEX were originated from both indoor and outdoor sources. A high correlation between indoor levels of NO and BTEX indicated that traffic emissions were also an important sources of BTEX.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.144-151
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• 2006

A measurement uncertainty for analysis of volatile organic compound (benzene) in cigarette mainstream smoke was carried out. In this study one point re-calibration method was used to estimate uncertainty for benzene. The measurement uncertainty was calculated based on the uncertainty sources of each analysis step, quality appraisal sources, drift and repeatability. As a result, the concentration and expanded uncertainty of benzene in cigarette mainstream smoke were measured as $38.08{\pm}4.36{\mu}g/cig$. Relative uncertainty of drift and repeatability obtained were 5% and 3%, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1306-1309
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• 2005

Highly efficient and bright organic light-emitting diodes (OLEDs) have been realized using the thin alkali compound films (TACFs) at the interface between an emitting layer and an electron transporting layer with conventional organic layers. By comparing the performance of the device as a function of position with the TACFs, we propose the optimal position of the TACFs in the tris-(8-hydroxyquinoline) aluminum (Alq3). A device with the ACFs showed high luminance of over 12 500 cd/m2, luminance efficiency of more than 12 cd/A, and power efficiency of more 4.5 lm/W, respectively.