• 대한화학회지
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• 제16권6호
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• pp.369-372
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• 1972

메탄올, N, N-dimethylformamide 및 acetonitrile속에서 이염기성 카르복시산 $(HOOC(CH_2)_nCOOH$, n=0∼4)의 해리상수를 유리전극을 사용하여 전위차법으로 측정했다. 두 용매간에서 각 산의 전해리상수의 차는 거의 일정한 값이 되며, 이 값은 일염기성 카르복시산의 해리상수의 차와 거의 일치했다. 그리고 $K_1/K_2$의 값은 양성자성용매인 물과 메탄올에서보다 반양성자성용매인 N,N-dimethylformamide와 acetonitrile에서 훨씬 더 크다.

• 대한화학회지
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• 제26권6호
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• pp.403-406
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• 1982

N, N-디메틸포름아미드 디알킬 아세탈류를 N-아실-1,4-디메톡시-2-나프틸아민의 몇 가지에 반응시켰더니 어느 경우에나 동일한 생성물인 N,N-디메틸-N'-2-(1,4-디메톡시)나프틸우레아 만이 생성 되었다. 이들 반응으로부터 N,N-디메틸포름아미드 디알킬아세탈은 반응 상대화합물에 전자밀도가 낮은 원자가 있을 때는 친핵 공격으로 반응하는 디메틸아미노화 시약으로 작용한다는 사실을 발견 하였다.

• 약학회지
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• 제9권1_2호
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• pp.4-7
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• 1965

Acid dissociation constants of sulfamethoxypyridazine, sulfadimethoxine, sulfamerazine, sulfathiazole and sulfadiazine, and stability constants for formation of copper chelate were calculated from their titration curves in 80% dimethylformamide with ionic strength 0.1 at $25{\deg}$ It was found that the acid dissociation constants (pKa) of sulfa-drugs were in the range of 9.33 - 10.05, and the stability constants (log $k_{1}$, $k_{2})$ of their copper chelates were in the range of 9.33-9.71.

• 한국대기환경학회지
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• 제26권4호
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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.

• 한국수정란이식학회지
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• 제24권4호
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• pp.275-279
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• 2009

The beneficial effect of glycerol as a cryoprotectant, especially for sperm cryopreservation, has been shown in many studies. However, glycerol is toxic to living cells, and boar sperm in particular show greater sensitivity to glycerol than sperm from other domestic animals. Amides have been studied as alternative cryoprotectants for freezing stallion sperm. Sperm frozen in methylformamide or dimethylformamide as cryoprotectants show similar motility when thawed compared with sperm frozen in glycerol. We evaluated the cryoprotective effects of dimethylformamide on boar sperm freezing. To test the effect of amides, the concentration of boar semen was adjusted to $10^9sperm/mL$, and seminal plasma was removed using Hulsen solution. After centrifugation, the pellet was diluted in modified-Modena B extender. Lactose-egg yolk (LEY) extender was used as the cooling extender. The freezing extender was madeed aaddition of the optimal amount of glycerol and amides to LEY-Glycerol-Orvus ES Paste extender, and this extender was used for the second dilution. Diluted sperm were frozen in liquid nitrogen using the 0.5 mL straw method. Sperm frozen in extender with glycerol as a cderol were compared with those frozen in extender including the different amides. Sperm were tested for motility, viability, the sperm chromatin structure assay, and normal apical ridge after thawing. The percent of motile sperm diluted in glycerol was as high as that in the stallion study (61%). Dimethylformamide showed positive effects on sperm quality and was better than glycerol. Methylformamide provided similar sperm quality as glycerol. Therefore, dimethylformamide is useful for reducing cryoinjury in boar sperm and is expected to be useful as an alternative cryoprotectant.

• Archives of Pharmacal Research
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• 제5권2호
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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.

• 품질경영학회지
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• 제45권4호
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• pp.769-780
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• 2017

Purpose: The aim of this study is to conduct a survey of dimethylformamide(DMF) content in polyurethane(PU)-based consumer products and provide the information for the PU manufacturer and company to prepare a countermeasure for improving the quality competitiveness. Methods: This study selected PU-based consumer products(toddler shoes, children's bag, children's play mat, safety gloves), which is closely used in everyday life, and analyzed the residual DMF content in the consumer products. Results: In this study, it was confirmed that the average DMF content of toddler shoes, children's bag, children's play mat and safety gloves are 38 ppm, 119 ppm, 396 ppm and 826 ppm, respectively. In addition, most of the samples were found to meet the internationally accepted standard of 1,000 ppm and the DMF contents were reduced from at least 63 % to 85 % with a single washing process. Conclusion: The domestic PU manufacturers should seek ways to reduce the DMF through their production facility applications and introducing new materials such as water-soluble PU, and preparing the process development for their quality competitiveness.

• 공업화학
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• 제25권5호
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• pp.526-530
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• 2014

2,2'-Bis[4-(3,4-dicarboxyphenoxy) phenyl]propane dianhydride와 3,5-diamniobenzoic acid의 반응에 의해 얻어진 폴리에테르아미드산을 안정제로 사용하여 스티렌을 분산중합하여 폴리스티렌-폴리에테르아미드산 코어-셀 입자를 얻었다. 폴리에테르아미드산의 결합 효율을 증가시키기 위하여 4-vinylbenzyltrimethylammonium chloride를 공단량체로 사용하였다. 에탄올-물(7 : 3) 혼합용액을 반응매질로 사용했을 때 입자의 안정성 가장 높았고 입자의 크기도 비교적 균일하였다. 폴리스티렌-폴리에테르아미드산 코어-셀 입자의 크기는 스티렌의 양에 비례하여 증가하였다. Dimethylformamide-물 혼합용액에서 중합한 경우에는 입자의 크기 분포가 넓어졌다. 폴리스티렌-폴리에테르아미드산 코어-셀 입자의 셀을 화학적으로 이미드화 하여 폴리스티렌-폴리에테르이미드 코어-셀 입자로 변환시켰다.

• Bulletin of the Korean Chemical Society
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• 제22권4호
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• pp.357-361
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• 2001

Frequency spectra of the complex permittivity of 2-methoxyethanol (2-ME) with water, ethanol, dimethylsulphoxide (DMSO), N,N-dimethylformamide (DMF) and N,N-dimethylacatamide (DMA) have been determined over the frequency range of 10 MHz to 20 GHz at 25 $^{\circ}C$, using the Time domain reflectometry method, for 11 concentrations for each system. The static dielectric constant, dielectric constant at microwave frequency, relaxation time, excess dielectric parameters, and Kirkwood correlation factor have been determined. The relaxation in these systems within the frequency range can be described by a single relaxation time constant, using the Debye model. The parameters show a systematic change with the concentration.

• 대한화학회지
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• 제31권6호
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• pp.486-490
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• 1987

$CCl_4$속에서 티오아세트산아미드(TA)와 몇가지 아미드(N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA) and N,N-dimethylpropionamide (DMP)) 사이의 수소결합이 TA의 N-C(S) 결합 주위의 부자유 회전에 미치는 영향을 nmr 분광학적인 방법으로 연구하였다. $CCl_4$분율이 증가할 때 TA의 $NH_2$기의 양성자 nmr 스펙트럼은 이중선으로 뚜렷하게 분리되었으며, 그 정도는 DMF < DMA < DMP순으로 증가하였다. 이런 현상을 TA와 아미드사이의 분자간 수소결합으로 설명하였다.