• Membrane Journal
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• v.23 no.6
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• pp.439-449
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• 2013

This study investigated the aromatic polyamide reverse osmosis membrane was modified with diphenylamine (DPA) for enhanced chlorine and fouling resistance and how to optimize. DPA has high reactivity and thermo chemical stability. The performance of a modified membranes was investigated and its surface analyzed using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contact angle measurement. The experiment was conducted while changing the conditions of temperature and DPA solution concentration.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.148-158
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• 2009

We tested and selected some agrochemicals reducing the occurrence of major pests and diseases during garlic storage. Tebuconazole, diphenylamine and prochloraz as fungicides and dimethate as a insecticide were sprayed or drenched before harvest. And the harvested garlic was dipped in each of the agrochemicals. The residues of pesticides in garlic bulbs treated were analyzed every month from harvesting time for 6 months. In case of Danyang garlic, which was treated with pesticides before and after harvesting, the residues of diphenylamine, tebuconazole, prochloraz, and dimethoate ranged from 0.008 to 0.28, from 0.03 to 0.32, from 0.02 to 0.12, and from 0.02 to 0.25 mg/kg, respectively. In case of Uiseong garlic, the residues of diphenylamine, tebuconazole, prochloraz and dimethoate ranged from 0.008 to 0.09, from 0.08 to 0.45, from 0.02 to 0.57, and from 0.04 to 0.38 mg/kg, respectively. And, in case of Namdo garlic, the residues of diphenylamine, tebuconazole, prochloraz, and dimethoate ranged from 0.008 to 0.52, from 0.07 to 1.67, from 0.02 to 0.17, and from 0.03 to 0.73 mg/kg, respectively. Some of the garlic samples treated with tebuconazole exceeded its maximum residue limits (MRLs) of 0.1 mg/kg set by Korea Food Drug Administration (KFDA), but dimethoate was detected below its MRL of 1.0 mg/kg. In case of diphenylamine and prochloraz, their MRLs for garlic were not set. Adapting their MRLs, 5.0 mg/kg of diphenylamine for apple and pear and 0.5 mg/kg of prochloraz for strawberry and grape, residue levels of diphenylamine and procloraz were below than their MRLs, with the exception of samples two times treated with procloraz in Namdo garlic. These results indicate that dimethoate can be used as an agrochemical to control the postharvest disease in garlic in only MRL aspect.

• Macromolecular Research
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• v.15 no.6
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• pp.575-580
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• 2007

Water-soluble, chiral conducting, poly(diphenylamine) (PDPA) nanocomposites were synthesized by chemical oxidative polymerization of diphenylamine in the presence of poly(acrylic acid) (PAA) as a template and camphor sulphonic acid (CSA) as the chiral inductor, Composites were formed as stable aqueous dispersions under different experimental conditions, such as DPA to PAA molar ratios, PAA molecular weight, etc. Circular dichroism(CD) spectra of the composites indicated the induction of chirality to PDPA. Compared to simple chiral PANI, the PDPA/PAA/CSA nanocomposites showed a different Cotton effect. The appearance of a CD band in the composite was complimentary to the bisignate, exciton-coupled band in the UV-Visible spectrum. FTIR spectra indicated the intimate mixing of PDPA and PAA.

• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.331-338
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• 2007

The major fungal diseases which effecting garlic storage are blue mold and dry rot, caused by Penicillium hirsutum and Fusarium oxysporum, respectively. In order to reduce the damage by the pathogenic fungi, here we report the effects of 11 fungicides tested to reduce spoilage during storage of garlics. In the in vitro antimicrobial activity test, the fungicides, diphenylamine, prochloraz and tebuconazole showed 0.3, 2.2, and 1.3 nun inhibition zone to F. oxysporium, and cyprodinil, diphenylamine, fenbuconazole, hexaconazole, penconazole, prochloraz, propiconazole, pyrimethanil and tebuconazole exhibited 0.2, 2.4, 0.8, 0.4, 1.2, 1.5, 1.2, 0.4 and 1.5 mm to P. hirsutum, respectively. To test the in vivo control effect, when the diphenylamine, prochloraz, and tebuconazole were treated by standard concentration, the fungal mycelium of F. oxysporium started to grow 5 days after inoculation, and 80, 63.3 and 83.3% of the inoculated cloves are infected 11 days after inoculation. When the tebuconazole were treated by standard concentration, the P. hirsutum was completely inhibited the growth of the fungi. In case of diphenylamine, penconazole and propiconazole treatment, the P. hirsutum was observed 7 days after inoculation and $20{\sim}23.3%$ of the cloves were infected 11 days after inoculation. When cyprodinil, prochloraz and pyrimethanil were treated, pathogens occurred 5 days after inoculation and $60{\sim}100%$ of the cloves infected 11 days after inoculation. Three fungicides such as diphenylamine, prochloraz and tebuconazole also suppressed remarkably the infection and growth of F. oxysporium and P. hirsutum on garlic when both of the pathogens are inoculated after the garlic cloves were dipped for 10 min in the suspension of each agrochemical. Overall, diphenylamine, prochloraz and tebuconazole showed effective control efficacy on dry rot and blue mold There was significant correlation between in vitro and in vivo assay in diphenylamine and prochloraz to F. oxysporum and cyprodinil, prochloraz and pyrimethanil to P. hirsutum.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1009-1011
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• 2004

In the present work a very simple, sensitive and selective spectrophotometric method for the determination of nitrite in micellar media is described. The method is based on the color reaction of nitrite with p-nitroaniline in the presence of diphenylamine in acid media. In order to remove the extraction step, Triton X-100, a non-ionic surfactant was used as micellar media. The optimum reaction conditions such as acid concentration, reagents concentration and effect of time have been studied and the analytical characteristics of the method such as limit of detection, linear range and molar absorptivity have been obtained. The interference of some anions and cations was also tested. The method was applied to the determination of nitrite in real samples.

• Analytical Science and Technology
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• v.19 no.3
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• pp.211-217
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• 2006

Diphenyl amine (DPA) was polymerized inside the channels of the mesoporous silica (MCM-41). MCM-41 (C) and MCM-41 (D) were prepared with cetyltrimethyl ammonium bromide (CTAB) and dodecyltrimethyl ammonium bromide (DTAB), respectively and used as hosts. Initially, the self assembly of DPA inside the pores of MCM-41 was made in ${\beta}$-naphthalene sulfonic acid (NSA) medium and subsequently poly (diphenylamine), PDPA was formed by oxidative polymerization. $N_2$ adsorption-desorption measurements of PDPA loaded MCM-41 (C) and MCM-41 (D) show variations in pore volume and surface area between them. A tubular form of poly (diphenylamine), PDPA was envisaged to form in the pores of MCM-41 and supported by high resolution transmission microscopy. The presence of PDPA inside the channel of MCM-41 was further confirmed by FTIR spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction.

• Macromolecular Research
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• v.17 no.9
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• pp.714-717
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• 2009

Hole transport copolymers consisting of 3,4-ethylenedioxythiophene (EDOT) and N-4-butylphenyl-N,N-diphenylamine (BTPA) were synthesized by oxidative coupling reaction using $FeCl_3$ as an oxidant. These copolymers showed good solubility and their thin films showed sufficient morphological stability. The copolymers showed an absorption maximum around 320 nm. Copolymers had an oxidation peak at approximately $1.03{\sim}1.14V$ versus the Ag/AgCl electrode. The hole mobility increased with increasing portion of the EDOT unit. The hole mobility of the copolymer containing 57% of the EDOT unit showed the highest mobility of $3{\times}10^{-5}cm^2/V{\cdot}s$.

• Journal of the Korean Chemical Society
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• v.11 no.4
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• pp.126-131
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• 1967

Various amines (Triethylamine, Diethylamine, Dimethylaniline, Pyridine and Diphenylamine) and electron acceptors (Carbontetrachloride, iodine monochloride and iodine) were reacted in the hexane solvent system to form a charge transfer complex in each case. The tendency of forming a charge transfer complex by these electron acceptors was proportional to the basicity of amines and the different type of complex was formed as the polarity of electron donor had markedly changed, which were identified by ultraviolet spectrophotometry. A correlation between the formation of complex and the basicity of amine and the polarity of electron acceptor was discussed.

• Journal of the Korean Chemical Society
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• v.18 no.6
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• pp.408-414
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• 1974

The direct reactions of titanium tetrachloride with piperidine and diphenylamine in dichloromethane have been studied by examining the isolated reaction products. In the reaction with piperidine, titanium tetrachloride undergoes both addition and substitution reactions as in the following: $TiCl_4+C_5H_{10}NH{\to}TiCl_4{\cdot}C_5H_{10}NH$$TiCl_4+C_5H_{10}{\to}TiCl_3{\cdot}NC_5H_{10}+HCl$ The addition reaction is relatively fast and completed in minutes whereas the substitution reaction is very slow. The both reaction products coprecipitated with piperidine hydrochloride formed during the substitution reaction were isolated and characterized. The reaction with diphenylamine resembles to the above reaction but the addition compound could be obtained in pure crystal form.

• The Korean Journal of Rheology
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• v.11 no.2
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• pp.91-96
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• 1999

Semiconductive polyaniline and its derivatives such as poly(aniline-co-sodium diphenylamine sulfonate), poly (aniline-co-o-ethoxyaniline), poly (o-methylaniline), and poly (o-methoxyaniline) were synthesized, and then adopted as suspending particles of the electrorheological (ER) fluids. All suspensions of these polyaniline derivatives showed typical ER properties under high applied electric fields. However, flow behaviors are observed to be quite different depending on the polyaniline derivatives, especially in the stress plateau regions obtained at low shear rates. Using a scaling law, we also obtained universal cures of ER fluids from the flow curves at each applied electric field based on the relationship between the dynamic yield stress with the applied electric field and flow curve changes according to the electric fields.