• 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.

• Korean Journal of Crystallography
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• v.5 no.2
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• pp.78-84
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• 1994

The crystal structure of N-11-(benzotriazol-1-yl)butyl]-P-nitroaniline ( C16H17N502) has been determinedfromsingle crystal x-ray diffractionstudy:C16H17N502 monoclinic, P21/n, a=17542(2)A, b=10.755(3)A, c=8.891(1)A, β=104.58(1)˚, V=1623.4(5)A3, 7=293(2)K, Z=4, Cuka(A = 1.5418A) , The molecular structure was solved was by direct meshed refined by full-matrix least squares to a final R =0.0411 for 2248 unique observed [F≥4o(p) ] reflections and 255 Parameters. The crystal structure is stabilized by intermolecular N (11) -Hl 1 (Nl 1) ‥‥N (3) hydrogen bond with N(11) ‥‥ N(3) =3.136(2)A and N(11)-Hll(Nll)‥‥N(3) =164.1(15) ˚.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.523-530
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• 2010

This study was conducted to analyze and determine formation potentials for chlorination disinfection by-products (DBPs) from 14 synthetic nitrogen compounds with or without $Br^-$. 5 of 14 compounds were 3-aminobenzoic acid, 2-aminophenol, aniline, anthranilic acid and 4-nitroaniline that were relatively shown high for formation of THMs/DOC whether or not $Br^-$ presented. 6 compounds that were p-nitrophenol, 3-aminobenzoic acid, 2-aminophenol, aniline, anthranilic acid and 4-nitroaniline were shown high for formation of haloacetic acids (HAAs)/DOC whether or not $Br^-$ presented. Trichloroacetic acid (TCAA) was dominated in 6 compounds. The formation of haloacetonitriles (HANs)/DOC whether or not $Br^-$ presented was high in 3-aminobenzoic acid, 2-aminophenol, aniline and anthranilic acid. Specially, aniline was detected 14.6∼16.1 ${\mu}g/mg$. The formation of chloral hydrate (CH)/DOC and chloropicrin (CP)/DOC were shown high in 3-aminobenzoic acid and 2-aminophenol in 14 compounds. 6 compounds (3-aminobenzoic acid, 2-aminophenol, aniline, anthranilic acid, 4-nitroaniline, p-nitrophenol) and a commercial humic acid were tested for the formation of DBPs/DOC whether or not $Br^-$ presented. When $Br^-$ was added, the DBPs/DOC was higher for the order of aniline> anthranilic acid> 3-aminobenzoic acid> 4-nitroaniline> humic acid> p-nitrophenol> 2-aminophenol. And when $Br^-$ was not added, the DBPs/DOC was higher for the order of anthranilic acid> aniline> p-nitrophenol> humic acid> 4-nitroaniline> 3-aminobenzoic acid> 2-aminophenol.

• 월간산업보건
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• s.189
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• pp.25-27
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• 2004

• 월간산업보건
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• s.188
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• pp.41-42
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• 2003

• YAKHAK HOEJI
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• v.34 no.6
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• pp.422-428
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• 1990

2,3-Dibromo-1,4-naphthoquinone was reacted with p-aminobenzoic acid, 2-aminopyridine, 2-amino-4-metylpyridine, m-nitroaniline, sulfathiazol, p-chloroaniline, phenetidine and 2-bromo-3-(N-arylamino)-1,4-naphthoquinones($1{\sim}8$). 2,3-Epoxy-2,3-dihydro-1,4-naphthoquinone was also reacted with p-amonobenzoic acid, p-toluidine, p-chloroaniline, m-chloroaniline, m-nitroaniline, p-phenetidine, N,N-dimethyl-1,4-pheylenediamine as a ring opening and dehydogenation to form 2-hydroxy-3-(N-arylamino)-naphthoquinones ($9{\sim}16$) in good yield. These new compounds($1{\sim}16$) are expected to have a biological activities such as anticoagulant and cytotoxic.

• Journal of the Korean Chemical Society
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• v.18 no.4
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• pp.251-258
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• 1974

The rate constants for the nucleophilic substitution reactions of substituted benzoyl chlorides with p-nitroaniline in such solvents as acetone, acetonitrile, methanol, ethanol, etc. were conductometrically determined, and the activation thermodynamic parameters were also evaluated. In result, the reaction rates were faster in protic solvents than in aprotic solvent; in the solvents of similar property, the reaction rate in the solvent of the large dielectric constant was faster than that in the solvent of the small dielectric constant. Hammett plots in individual solvents showed the straight lines with positive slope; and we concluded that the reaction occurred via the addition-elimination mechanism.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.60-65
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• 1961

Nowadays, it is a well-known fact that the epoxy resins play an important role in the industrial field of plastics because of their excellent properties. Although studies on the polymers of epichlorohydrin with phenols, up-to-date, were various, there were only a few wokrs on the polymers of epichlorohydrin with amines. Therefore the experiments are carried out about the polymerization of epichlorohydrin with ${\alpha}-, {\beta}$-naphtylamine, o-, m-, p-toluidine, and o-, m-, p-nitroaniline. Examining the polymerization processes and the differences in the properties of the polymers, we obtained the following conclusions. 1) ${\alpha}$-naphthylamine, ${\beta}$-naphthylamine, o-toluidine, m-toluidine and p-toluidine react with epichlorohydrin to form polymers but o-, m-, and p-nitroaniline do not make polymers with epichlorohydrin. 2) As polymerization times after adding sodium hydroxide and refluxing again 3hrs. are suitable for ${\alpha}$-naphthylamine-epichlorohydrin, 3.5hrs. for${\beta}$-naphthylamine-epichlorohydrin, and 4hrs, for m-toluidine-epichlorohydrin. 3) Method for determining molecular weight of these polymers by the titration of end group is applicable to the polymers having D.P. less than about 200 for ${\alpha}$-, ${\beta}$-naphthylamine-epichlorohydrin and those having D.P. less than 18 for m-toluidine-epichlorohydrin. 4) Gererally, these polymers get special colors so that these need proper pigmentation to use as molding compounds.

• Journal of the Korean Chemical Society
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• v.39 no.11
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• pp.863-868
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• 1995

We have prepared microcolumns made of stainless steel tubing, glass-lined stainless steel tubing, and silica-lined stainless steel tubing and examined their performances comparatively. The length of columns was fixed as 30 cm, and the I.D.'s, either 1 mm or 0.5 mm. Octadecyl bonded silica paticles $(5\mu)$ were used as the stationary phases. p-Nitroaniline, N,N-dimethyl-o-nitro-p-toluidine,and ethylbenzene were used as the test solutes. The glass-lined or silica-lined stainless steel columns showed better performances than the plain stainless steel column did. The number of theoretical plates over 10,000 were obtained even for the 0.5 mm I.D. (30 cm long) column as long as the glass-lined stainless steel tubing was used.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1210-1215
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• 1999

Optimum conditions of the hydrogenation of PNA to pure PPD were determined in a three-phase slurry reactor with suspended Pd/C catalyst particles. Minimization of mass transfer resistances at the interfaces of both gas-liquid and liquid-catalyst particles and control of overall reaction rate on catalyst surface leaded to decrease the hydrogen starvation on reaction active sites and to reduce the side reactions during hydrogenation. The optimum temperature, pressure, and catalysst concentration were confirmed to be in the range of $60^{\circ}C$, 60~70 psig, and 1~2 g-cat/L, respectively. Reaction rate was zero order with respect to the concentration of PNA and 1st order with respect to the pressure of hydrogen(P). Overall rate expression of the reaction was $R_A=6.44{\times}10^6{\cdot}H{\cdot}P{\cdot}m{\cdot}$exp(-4659/T) where H is constant, m is concentration of catalyst, and T is temperature.