• Elastomers and Composites
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• v.55 no.3
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• pp.191-198
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• 2020

Nickel oxide (NiO) nanoparticles were synthesized by a reaction of nickel nitrate hexahydrate (Ni(NO₃)₂·6H₂O) and sodium hydroxide (NaOH). The synthesized NiO nanoparticles were examined with X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and ultraviolet-visible (UV-vis) spectroscopy. The NiO nanoparticles were used as the catalyst for the reduction of o- and m-nitroaniline to phenylenediamine. The reduction rate of m-nitroaniline was faster than that of o-nitroaniline. The reduction rate for both o- and m-nitroaniline increased as the reaction temperature increased. The rate of reduction for nitroaniline followed a pseudo first-order reaction rate law.

• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.391-394
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• 1973

A semiempirical molecular orbital theory which is known as extended H ckel theory is applied to explain the sweet taste mechanism of nitroaniline, 1-methoxy-4-nitroaniline, and 1-ethoxy-4-nitroaniline which has different sweetness respectively. In this paper, the assumption is made that the nitroaniline is coplanar. The relationship between charge density and sweetness has been calculated according to the geometrical rotation of the orthosubstitute of nitroanilines. It has been shown that the calculated results are consistent with the experimental order of the relative sweetness.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.349-358
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• 1997

meta-Nitroaniline(mNA) crystals were grown from the supercooled melt for the first time. A seed was introduced into the purified mNA melt of 100 ml 0.1 K above the melting temperature ($T_m$ : $112.0^{\circ}C$) and crystal was grown at constant supercooling of 0.1 K. The melt was stirred . mechanically and the crystal was also rotated while the growth proceeds. mNA crystals of size up to $20{\times}15{\times}15 \textrm {mm}^3 and of very high perfection could be grown for the period of one day. The bottom half of the crystal faces are well-faceted and covered by {111} and {021} faces, while the faces of the top half are not well defined. The overall crystal morphology was characterized by the unidirectional growth along one of the polar axes. The absolute direction of preferred growth was determined to be [001] by the pyroelectric measurements. The perfection of the crystal was characterized by synchrotron X-ray topography and optical characterization was made by measuring second harmonic conversion efficiency.

• Elastomers and Composites
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• v.54 no.2
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• pp.105-109
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• 2019

Gold nanoparticles were synthesized by reacting potassium tetrachloroaurate ($KAuCl_4$), potassium carbonate ($K_2CO_3$), and isopropyl alcohol in the presence of fullerene oxide [$C_{60}(O)_n$, $n{\geq}1$], which was, in turn, prepared from [$C_{60}$] fullerene and m-chloroperoxybenzoic acid under refluxing conditions. The crystallinity and morphology of the prepared gold nanoparticles were confirmed by UV-vis spectroscopy, X-ray diffraction, and scanning electron microscopy. The activity of the gold nanoparticles in the reduction of 4-nitroaniline was measured in order to determine its capability as a catalyst.

• 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.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.

• Korean Journal of Food Science and Technology
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• v.6 no.1
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• pp.6-11
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• 1974

Four new compounds; 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-nitroanilino)$ propionoxy} benzene]; m.p. $200{\sim}202^{\circ}C,\;C_{31}H_{22}O_8N_4Cl_6$ 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(p-nitroanilino)$ propionoxy} benzene]; m.p. $168-170^{\circ}C,\;C_{31}H_{22}O_8N_4Cl_6$ : 2,2'-Methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-chloro-p-nitroanilino)$ propionoxy} benzene]; m.p. $170.5-172.5^{\circ}C,\;C_{31}H_{20}O_8N_4Cl_8$ : 2,2'-Methylene-bis [3, 4, 6-trichloro ${{\beta}-(c-methyl-p-nitroanilino)$ propionoxy} benzene]; m.p. $163-164^{\circ}C,\;C_{33}H_{26}O_8N_4Cl_6$-were synthesized by Mannich reaction from 2,2'-Methylene-bis (3, 4, 6-trichloroacetoxy benzene) and their antimicrobial activities against the microorganisms Staphylococcus aureus, Escherichia coli, Bacillus subtilis Natto, Brevibacterium ammoniagenes, Candida tropicalis, Rhodotorula glutinis, Pseudomonas ovalis, Aspergillus candidus Link, Aspergillus awamori Nakazawa. Aspergillus niger var. Tieghem, Aspergillus usami Sakakuchi, Penicillium notatum-were tested. 2,2'-methylene-bis [3, 4, 6-trichloro ${{\beta}-(o-nitroanilino)$ propionoxy} benzene] showed a strong antimicrobial activity against Bacilus subtilis Natto and Brevibacterium ammoniagenes.

• 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.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.689-695
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• 1998

Carbobenzoxy-alanyl-thiaarginine benzyl ester and carbobenzoxy-alanyl-thialysine benzyl ester were synthesized in solution. Kinetic studies were carried out using three different analytical methods, semi-classical method, progress curve analysis and competitive spectrophotometry. In competitive spectrophotometry, carbobenzoxy-valyl-glycyl-arginyl-p-nitroaniline was used as a detector. Kinetic constants such as $K_m$ and $V_{max}$ measured by competitive spectrophotometry are almost the same as those values measured by semi-classical method. Colorimetric Ellman's assays showed the thio-peptido mimetics to be a suitable substrates for trypsin. Kinetic studies with trypsin gave $K_m$ of 2.33 mM and $k_{cat}$ of $1.50{\times}10^5\;min^{-1}$ for carboxy-alanyl-thiaarginine benzyl ester and $K_m$ of $3.41{\times}10^{-3}\; Mm\; and\; k_{cat}\; of\; 520{\times}102\; min^{-1}$ for carbobenzoxy-alanyl-thialysine benzyl ester, respectively. Kinetic constants $(K_m=2.04{\times}10^{-2}\; mM, K_{cat}=4.42{\times}10^3 \;min^{-1})$ for natural substrate, carbobenzoxy-alanyl-lysine benzyl ester, were also evaluated by competitive spectrophotometry in order to compare the mode of binding on trypsin.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.137-143
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• 2003

To validate and to estimate the chemical hazard playa very important role to environment and human health. The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this resepct, the clastogenicity of 8 synthetic chemicals was evaluated with bone marrow micronucleus assay in mice. The positive control, mitomycin C(2mg/kg,i.p.) revealed significant induction ratio of percentage of micronucleated polychromatic erythrocytes/l,000 polychromatic erythrocytes compared to carboxymethylcellulose control. The chemicals with relatively high LD$\_$50/ value such as phenylisocyanate (CAS No. 103-71-9), m-aminochlorobenzene (CAS No. 108-42-9) and 2-chloro-4-nitroaniline (CAS No. 121-87-9) revealed no significant induction of micronucleated polychromatic erythrocytes in mice. From this results, 8 synthetic chemicals widely used in industry have revealed no significant micronucleus induction of clastogenicity in mice in this experiment.