• Journal of the Korean Chemical Society
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• v.16 no.6
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• pp.369-372
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• 1972

The dissociation constants of dibasic carboxylic acids $(HOOC(CH_2)_nCOOH$, n = 0~4] in methanol, N, N-dimethylformamide and acetonitrile have been determined by the potentiometric method with a glass electrode. The difference between over-all dissociation constants in each other solvent is found to be of the same order of magnitude, and the $K_1/K_2$ ratios in aprotic dimethylformamide and acetonitrile are much greater than those in protic methanol and water.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.2
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• pp.103-109
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• 2011

Object: we investigated some factors which can affect workers' comprehension of chemical hazard information and their actions to protect themselves from the hazard. Method: Comprehension score of chemical hazard information and the rate of wearing personal protective equipment (PPE) was surveyed for the 109 workers from 15 factories who were exposed to N, N-dimethylformamide. Difference of the worker's comprehension score of hazard information was analyzed by education interval, work duration and the way of occupational safety and health management between self-managed or sub-contracted. Result: Mean comprehension score of N, N-dimethylformamide hazard, which was given as a short quiz composed of 10 "true" or "false" problems, was 65%. Mean percentage of wearing PPE was improved as the education program was done within a month but decreased after 6 months. Eighty seven % of workers got the chemical hazard information from the material safety data sheet placed at workplace. Conclusion: Education interval and comprehension score affected the rate of wearing PPE. The way of occupational safety and health management self-managed or sub-contracted did not affect the workers' comprehension score on hazard information nor the rate of wearing PPE.

• Journal of the Korean Chemical Society
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• v.26 no.6
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• pp.403-406
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• 1982

Reactions of N-acyl-1,4-dimethoxy-2-naphthylamines with N,N-dimethylformamide dialkyl acetals afforded, in all cases, the same product, N,N-dimethyl-N'-2-(1,4-dimethoxy)naphthylurea. In these reactions, it was observed that N,N-dimethylformamide dialkyl acetals act as a dimethylamination agent when electron-deficient cites are present in the substrates.

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.97-101
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• 1982

Depending upon the results obtained by the bromolactonization of olefinic acids (9-11) by means of N-bromosaccharin (4), the influence of the stabilities of the imidic anions resulted from heterolytic cleavage of N-haloimides, such as N-bromosuccinimide (1), N-bromophthalimde (2), and N-bromosaccharin (3) in dry N, N-dimethylformamide on the reactivity is elucidated.

• Journal of the Korean Chemical Society
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• v.37 no.8
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• pp.730-734
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• 1993

The electrochemical reduction behavior or Biliverdin (BV) in N,N-dimethylformamide solvent was studied by DC polarography, cyclic voltammetry and the controlled potential coulometry. The reduced product was indentified by UV-Vis spectroscopy. In DC polarogram, two reduction waves of BV were founded. The half wave potentials of two reduction waves were -0.71 and -0.91 V vs. Ag/Ag$^+$ respectively. The current type of the 1st reduction wave was diffusion-controlled and the 2nd was diffusion current containing a little kinetic current. The 1st electrochemical reduction process was irreversible and BV reduced to Bilirubin.

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.249-259
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• 1988

The solvent effects of MeOH-solvent dimers were studied via AM1 Hamiltonian and supermolecule methods. Methanol, ethanol, acetone, dimethylsulfoxide, N,N-dimethylformamide, tetrahydrofuran, dioxane, and acetonitrile were considered as solvent molecules. Optimized geometries, electron densities, molecular energies, and hydrogen-bonding energies of monomers and dimers were calculated. We found that the stabilization energies contributed to the hydrogen-bonding were decreased in the order of dimethylsulfoxide > ethanol > N,N-dimethylformamide > acetone > methanol > tatrahydrofuran > dioxane > acetonitrile, and this order was explained by using the change of electron density and energy partition functions.

• Journal of the Korean Chemical Society
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• v.16 no.3
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• pp.149-156
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• 1972

The responsive characteristics of hydrogen-responsive glass electrode in various buffer solutions of methanol, N,N-dimethylformamide and acetonitrile were examined. The potentials were attained more rapidly with an electrode stored in the same solvent medium than that stored in water before use. However, the time to be required for a stable potential increased with the basicity of buffer solution, and it was not provide a constant potential in the strong basic solution of these solvent. Even in acidic solution, the potential was varied according to the past usage of the electrode.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1424-1426
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• 2010

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.93-96
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• 1982

By using recemic 3-bromo-5-isobutyl-5-methylhydantoin (3a') in dry N, N-dimethylformamide which is a model reagent for asymmetric bromolactonization, bromolactonization of a series of olefinic acids was carried out to furnish corresponding bromolactones in moderate yields.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.4
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• pp.357-366
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• 2010

The purpose of this study is to evaluate a method for the measurement of N,N-Dimethylformamide (DMF) and to apply the method to the ambient air samples. For the determination of DMF together with other general VOCs (e.g., benzene, toluene, and xylenes), adsorption sampling and thermal desorption with GC/MS was used in this study. The sampling and analytical approaches tested in this study showed a good repeatability and linearity with lower detection limits of less than 0.35 ppb. Field measurements were carried out at three industrial sites (Daegu-Seongseo, Siwha and Banwall industrial complexes) and one residential site in Daegu city during a period from October 2006 to November 2008. DMF was detected in 71.8% of the total samples from the Seongseo industrial complex, well known for textile industry. In contrast, DMF was detected in only 20.4% and 12.9% of all the samples from the other two sites in Banwall and Siwha industrial complexes, respectively. This implies that sources of DMF should be strongly associated with textile industry. The mean concentration of DMF also appeared to be the highest in Seongseo site (5.95 ppb), followed by a residential site in Daegu (3.28 ppb), Banwall (0.88 ppb) and Siwha (0.55 ppb). In this study, we demonstrated the environmental significance of DMF in urban ambient air. To our knowledge, the DMF measurement introduced in this paper is the first case of an official report in Korea.