• Applied Biological Chemistry
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• v.31 no.1
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• pp.79-85
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• 1988

The effects of herbicides on biochemical processes in soil environment were studied by examining the effects of the chemical structure of each herbicides on soil enzyme activities and pesticides residue revealed when soil treated with urea was incubated at $28{\pm}1^{\circ}C$ for 56 days. The inhibition effects of herbicides on soil enzyme activites in soil decreased in the order of urea group>dinoseb>propanil>diphenyl eter group>acid amide group for urease, and dinoseb>urea group>diphenyl ether group>acid amide group for L-glutaminase and protease, dinoseb>diphenyl ether group>urea group>acid amide group for phosphatase. Herbicides inhibited the activities of soil enzyme in the early stage of treatment but increased the activities of urease, L-glutaminase and protease in the late stage. When herbicides were treated in soil together with urea the degradation of insecticides was accelerated.

• Journal of Pharmaceutical Investigation
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• v.18 no.3
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• pp.113-123
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• 1988

A series of water-soluble polyparacyclophanes bearing two diphenylmethane or two diphenyl ether skeletons were investigated to develop useful host compounds by using 1-anilinonaphthalene-6-sulfonate (ANS) and 2-p-toluidinylnaphthalene-6-sulfonate (TNS) as fluorescent hydrophobic substrates in aqueous solution. It was noteworthy that remarkable fluorescent enhancements and blue shifts of ANS and TNS were observed only in the presence of 1,6,20,25-tetraaza[6.1.6.1] paracyclophane (CPM 44) and 1,6,21,27-tetraaza [7.1.7.1] paracyclophane (CPM 55) for diphenylmethane skeleton, and 1,7,21,27-tetraaza-14,34-dioxa [7.1.7.1] paracyclophane (CPE 55) and 1,8,22,29-tetraaza-15,36-dioxa [8.1.8.1] paracyclophane (CPE 66) for diphenyl ether skeleton, comparing with ${\alpha}-\;and\;{\beta}-cyclodextrins$. However, their acyclic analogues such as 4,4'-dimethylaminodiphenylmethane and 4,4'-dimethylaminodiphenyl ether, and paracyclophanes whose cavities were smaller showed only small effects under the same conditions. These facts suggested that hosts and substrates were in an intimate contact which would not occur without larger structures, and thus that guest molecules were strongly incorporated in the hydrophobic cavities of these larger paracyclophanes. The effects of pH on the fluorescent intensity of ANS-CPM 44, ANS-CPM 55, ANS-CPE 55, ANS-CPE 66, TNS-CPM 44, TNS-CPM 55, TNS-CPE 55 and TNS-CPE 66 systems were not significant below pH 2.0, but their fluorescent intensities were markedly reduced with increasing ionic strength.

• Archives of Pharmacal Research
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• v.26 no.7
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• pp.535-539
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• 2003

The EtOAc soluble fraction from the stem of Sorghum bicolor showed a strong free radical scavenging activity. Five major compounds were isolated from this fraction. They were identified by spectral data as methyl ferulate (1), methyl p-hydroxycinnamate (2), p-hydroxybenzaldehyde (3), tricin (4), and quercetin 3,4 -dimethyl ether (5). Among these compounds, 1 exhibited a strong, free radical scavenging activity on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) with an $IC_50$ value of 0.7 $\mu$M. We further studied the effects of these isolated compounds on the lipid peroxidation in rat liver microsomes induced by non-enzymatic method. All five compounds showed anti-lipid peroxidation activity ($IC_50$ values of 0.5, 0.4, 0.3 and 0.3 $\mu$ M, respectively).

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2020-2024
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• 2007

The article reports the synthesis of a novel bispyridino-18-crown-6 ether, 7-{[(5S,15S)-5,15-diphenyl- 3,6,14,17-tetraoxa-23,24-diazatricyclo[17.3.1.18,12]tetracosa-1(23),8(24),9,11,19,21-hexaen-10-yl]oxy}heptylferrocenamide 6, bearing the C2-symmetric diphenyl substituents as chiral barriers and the ferrocenyl groups serving as an electrochemical sensor, and its electrochemical study with D- and L-AlaOMe·HCl as the guest by cyclovoltametry.

• Journal of Embryo Transfer
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• v.26 no.4
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• pp.297-304
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• 2011

Polybrominated diphenyl ethers (PBDEs) are a class of "brominated" (bromine containing) man-made chemicals used as flame retardant additives in plastics, foams, and textiles. PBDEs are found in various environmental contaminants in air, soil, sediment, and water, and 209 individual forms (congeners) of PBDE exist. Among these, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) is the dominant congener found in the environment. Exposure to BDE-47 is now worldwide, and levels of BDE-47 have been detected in the blood of animals, including humans. BDE-47 can adversely affect the developmental system in both humans and animals. BDEs have structural similarities to polychlorinated biphenyls and thyroid hormones. However, recent studies have shown that BDEs may act as hormonal disrupting chemicals with detrimental effects. Therefore, a reliable assessment of BDE-47 toxicological action is required to understand the detrimental impacts of BDE-47 on human health. In this review, we overview recent studies on the distribution and potential toxicological effects of BDE-47 in humans and animals.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2005.06a
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• pp.338-338
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• 2005

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.69-75
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• 1998

Responses of tobacco(Nicotiana tabacum cv. Xanthi) leaves of different age to diphenyl ether herbicide oxyfluorfen were evaluated with respect to cellular leakage, chlorophyll loss, and membrane lipid peroxidation. When tobacco leaves of different age were incubated under light condition at $25^{\circ}C$ following 12hr dark incubation. Significant electrolyte leakage from the treated tissues into the bathing medium occurred. The change of electrolyte leakage was proportional to the oxytluorfen concentration and the duration of light exposure to the tissues. Electrolyte leakage from the tissues treated with oxyfluorfen was highly dependent on the leaf age. From the tissues of younger age, more electrolyte leakage occurred and lag period was greatly reduced. Chlorophyll loss and membrane lipid peroxidation, as measured by malondialdehyde production, caused by oxyfluorfen treatment were also dependent an the age of treated leaf tissues. In conclusion, physiological responses of tobacco leaves to oxyfluorfen greatly varied with the age of treated tissues, and thus tobacco plants could be used as appropriate materials for studying the mechanisms of tolerance to diphenyl ether herbicides.

• Journal of the Korean Vacuum Society
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• v.7 no.3
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• pp.229-236
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• 1998

In this paper, thin films of Polyimide (PI) were fabricated by vapor deposition polymerization method (VDPM) of dry processes. The film's properties with curing temperature and electrical properties were studies. The synthesis of hexafluoroisopropyliden-2,2-bis[phthalic anhydride](6FDA) and 4, 4'-diamino diphenyl ether (DDE) was carried out by vapor deposition polymerization(VDP) with the same deposition rate. The evaporation temperature of 6FDA and DDE were $214^{\circ}C$ and $137^{\circ}C$, respectively, so as to preserve balance of stoichiometry. The polymic acid (PAA) made by VDPM were changed to PI by thermal curing. The uniformity and density of PI thin films were increased according to increasing curing temperature. The relative permittivity and dissipation loss factor were 3.7 and 0.008 at the frequency of 100Hz~200KHz, respectively, for the fabricated in the curing temperature of $300^{\circ}C$. Also, the resistivity was about 1.05$\times$$ 10^{15}$$\Omega$cm at $30^{\circ}C$.

• Journal of Adhesion and Interface
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• v.23 no.4
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• pp.137-143
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• 2022

In this study, the polyurethane acrylates (PUA) resin with good adhesive and flexibility for adhesive for shoes and clothing were synthesized using that poly(tetramethylene adiphate glycol) (PTAd), poly(tetramethylene ether glycol) (PTMG) as polyester polyol and polyether polyol respectively, including 4,4'-methylene diphenyl diisocyanate (MDI), isophorone diisocyanate (IPDI), 1,4-butandiol (1,4-BD), 2-hydroxyethyl methacrylate (2-HEMA) and dibutyl amine (DBA). The effect of polyol blend in the polyurethane acrylate on thermal and mechanical properties, adhesion strength and flexural strength were studied. The glass transition temperature (T_g) of PUA was confirmed in range of -70~-40 ℃. In addition, the glass transition temperature (T_g), decomposition temperature (T_d), tensile strength adhesion strength and heat resistance were increased as increasing of PTAd amount while the elongation, water resistance and flexural properties were decreased. The synthesized polyurethane acrylate with 5:5 ratio of PTAd and PTMG indicated the highest adhesion strength and flexural properties.

• Journal of Korean Society on Water Environment
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• v.33 no.6
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• pp.754-768
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• 2017

Polybrominated diphenyl ethers (PBDEs) are a group of industrial aromatic organobromine chemicals that have been used since the 1970s as flame retardants in a wide range of consumer products and articles, including plastics, computers, textiles and upholstery. Commercial PBDEs were added to Annex A of the Stockholm Convention as persistent organic pollutants in May 2009. PBDEs are still frequently found in sludge and effluent from wastewater treatment plants, even though commercial PBDEs were prohibited or voluntarily phased out several years ago. Conventional wastewater treatment processes are not designed to effectively remove PBDEs. This indicates that there is an urgent need for new developments and improvements to enhance upon the treatment techniques which are currently available. Several studies have suggested the potential removal and degradation technologies for PBDEs in wastewater. In this study, the concentrations and compositional profiles of PBDE congeners in sludge and effluent are investigated by analyzing the relevant literature data in relation to their usage patterns in commercial products in North America and South Korea. The strengths and weaknesses of the current PBDEs removal techniques (i.e., biodegradation, zero-valent iron, photolysis, sorption, etc.) are discussed critically. In addition, future research direction regarding the treatment and removal of PBDEs from wastewater is also suggested, based on the literature review.