• 대한화학회지
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• 제13권1호
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• pp.68-74
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• 1969

${\alpha},{\beta$}-dichloro-${\beta$}-phenyl propionate, Ethyl ${\alpha},{\beta$}-dibromo-${\beta$}-phenyl propionate, Etyyl ${\alpha},{\beta$}-dichloro-${\beta$}-(p-chlorophenyl)propionate, 및 dibromo-styrene 等의 化合物을 各種溶媒(dimethly formamide, diethylene glycol, 및 diethylene glyco monomethyl ether 等) 存在下에서 弗化反應을 시켜 보았으며 放射性弗素-18을 追跡子로 使用하여서 위의 化合物들의 弗化카리에 對한 反應度를 檢査하여 보았다. 一般的으로 弗化反應 生成物은 모노弗化物과 脫할로겐된 二重結合物을 生成하였다. diethylglycol 存在下에서 高溫反應시킨 條件下에서는 二重結合生成物이 많았고 diethylene glyco-monoethyl ether 存在下에서 低溫反應시킨 條件下에서는 弗化物이 多量生成하였다. 모노弗化物의 合成方式 및 確認方法에 關하여 說明하였으며 本反應의 合成上의 用途($F^{18}$ 標識化合物包含)에 言及하였다.

• KSBB Journal
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• 제19권2호
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• pp.164-167
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• 2004

효소인 싸이클로덱스트린글루카노트란스퍼라제 (CGTase)는 효소의 활성도에 칼슘이 관련된 분자내 당 전이반응에 의해 녹말과 그에 관련된 $\alpha$-1,4-glucan의 기질을 싸이클로덱스트린으로 생성시키는 산업적으로 가장 많이 응용되는 효소 중에 하나이다. 수용성 녹말을 기질로 하여 CLEC화한 Bacillus macerans $\alpha$-CGTase 효소를 극한의 반응 조건인 계면활성제나 유기 용매가 혼합된 반응조건에서 실험한 결과, 이들 조건이 싸이클로덱스트린의 생산을 증가시키는 영향을 초래하였고 특히, 계면활성제인 SDS와 $\beta$-OG는 전체 싸이클로덱스트린의 생성을 증가시켰고 이 중에서 SDS와 Lubrol PX는 알파싸이클로덱스트린의 생성의 특이성의 결과를, 반면에 Triton x-100과 Tween 80은 알파싸이클로덱스트린의 생성을 억제하는 결과를 보였다. 유기용매인 DMSO, formamide, MPD, ethylene glycol 또한 사이클로 덱스트린의 전체 수율과 특이성에 영향을 미치는 효력을 보였다.

• 폴리머
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• 제33권4호
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• pp.384-388
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• 2009

폴리아크릴로니트릴(PAN)과 셀룰로오스 아세테이트(CA) 블렌드/디메틸포름아미드(DMF) 용액의 유변학적 특성을 온도와 블렌드 조성비에 대하여 조사하였다. 모든 고분자 용액이 온도 변화에 따라 매우 특징적인 유변학적 거동을 보였다. 8 wt% 용액의 경우 $20{\sim}60^{\circ}C$ 온도범위에서 온도의 증가와 더불어 용액의 점도가 증가하고 손실탄젠트값이 감소하였다. $20^{\circ}C$에서는 용액의 물성이 블렌드의 조성에 영향을 받았으나 40 및 $60^{\circ}C$에서는 조성비가 용액 물성에 미치는 영향이 크게 감소하였다. 더 높은 온도에서의 더 긴 분자 이완시간으로부터 온도가 증가함에 따라 분자간력에 의한 물리적 구조 형성이 촉진된다는 것을 알 수 있었다. 이러한 유변학적 특성에 대한 원인은 묽은 용액의 특성으로부터 유추할 수 있었다. 고분자 용액의 고유점도가 온도가 증가함에 따라 감소하였다.

• 한국재료학회지
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• 제3권3호
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• pp.207-214
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• 1993

$Li_2O-Al_2O_3-SiO_3$계 결정화유리의 저온합성을 위하여 출방원료로서 각 해당 금속 알콕시드를 사용하였다. 알코올을 용매로 충분히 첨가하고, drying control chemical additive로 dimethy1 formamide를 적당량 첨가한 혼합용용액을 과잉의 물로 충분히 가수분해시킨 습윤겔을 저온으로 건고하여 균열이 없는 건조된 monolith겔을 합성하였다. 건조겔로부터 750-$950^{\circ}C$로 10시간 이상 소결하여 저열팽창성을 나타내는 ${\beta}$-eucrypytite(${\beta}$-quartz 고용체), $Li_2O\cdot Al_2O_3\cdot 3SiO_2$및 ${\beta}$-spodumene등의결정상을 석출시켰다.

• 생태와환경
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• 제41권4호
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• pp.485-489
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• 2008

Algal chlorophyll-$\alpha$ is commonly determined by spectro-photometric method using 90% acetone as solvents. However, acetone has low extraction efficiency without grinding filters, and DMF (dimethyl formamide) was tested for the compatibility with acetone. Chlorophyll-$\alpha$ concentration was determined for samples from 5 reservoirs of different trophic states and phytoplankton composition, using acetone extraction with grinding and DMF without grinding. Chlorophyll-$\alpha$ measured by DMF and Acetone did not show a significant difference when using trichromatic method of UNESCO and Lorenzen, and therefore, DMF can substitute acetone. But when acidification method was applied, they showed significant difference of 8%. It can be concluded that DMF can extract chlorophylls more effectively without grinding and it can be a better alternative for the standard extraction solvent.

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.719-728
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• 2005

A novel 2-amino-4-(8-quinolinol-5-yl)-1- (p-tolyl)-pyrrole-3-cabonitrile (2) was obtained by the reaction of 2-[2-bromo-1-(8-hydroxyquinolin-5-yl)-ethylidene]-malononitrile (1) with p-toluidene. The new synthon compound (2) could be annelated to the corresponding pyrrolo[2,3-d]pyrimidines (4, 6, 7, 26-28), triazolo[1,5-c]pyrrolo[3,2-e]pyrimidines (10, 29, 30), pyrrolo[2,3-c]pyrazoles (11-15), pyrrolo[1,2-a]pyrrolo[3,2-e] pyrimidine (17) and imidazo[1,2-c]pyrrolo[3,2-e]pyrimidines (18-25) via the reaction with some reagents such as acetic anhydride, formamide, triethyl orthoformate, hydrazine hydrate, hydroxylamine, ethylenediamine, carbon disulfide and phosphorus oxychloride. Chemical and spectroscopic evidences for the structures of these compounds are presented. The antifungal and antibacterial activity of the newly synthesized comounds were evaluated.

• Advances in materials Research
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• 제3권2호
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• pp.117-128
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• 2014

Processable conducting polyaniline derivative with free amine functional groups was successfully synthesized from the monomer o-phenylenediamine in aqueous hydrochloric acid medium using ammonium persulfate as an oxidative initiator. The synthesized poly(o-phenylenediamine) (PoPD) in critical condition was found to be completely soluble in common organic solvents like dimethyl sulfoxide, N,N-dimethyl formamide etc. From the intrinsic viscosity measurement, the optimum condition for the polymerization was established. The polymer was characterized by ultraviolet visible spectroscopy, Fourier transform infrared spectroscopy, proton magnetic resonance spectroscopy ($^1HNMR$) and thermogravimetric (TGA) analyses. The weight average molecular weights of the synthesized polymers were determined by the dynamic light scattering (DLS) method. From the spectroscopic analysis the structure was found to resemble that of polyaniline derivative with free amine functional groups attached to ortho/meta position in the phenyl ring. However, very little ladder unit was also present with in the polymer chain. The moderate thermal stability of the synthesized polymer could be found from the TGA analysis. The average DC conductivity of $2.8{\times}10^{-4}S/cm$ was observed for the synthesized polymer pellet after doping with hydrochloric acid.

• 한국전기전자재료학회논문지
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• 제22권4호
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• pp.297-302
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• 2009

We have successfully fabricated the alumina thick films using inkjet printing processes without a high temperature sintering process. Alumina suspension as dielectric ink was formulated by combining nano-sized alumina powders with an anionic polymer dispersant in formamide/water as co-solvent. The thickness of the printed alumina thick film was measured at around 5 um by field emission scanning electron microscope. The calculated packing density of 68.5 % from the printed alumina thick film was much higher than the same films fabricated by conventional casting or dip coating processes. Q factor of the dielectrics thick film infiltrated with cyanate ester resin was evaluated by impedance analyzer.

• 한국염색가공학회지
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• 제15권2호
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• pp.68-75
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• 2003

In this work, ultrafiltration(UF) membranes were prepared using polyethersulfone(PES). The polymer was dissolved in various solvent, such as N, N-dimethyl formamide(DMF), N,-dimethyl acetamide (DMAc), N,N-dimethyl sulfoxide(DMSO) and N-methyl-2- pynolidone(NMP). Each polymer solution was casted on the glass plate, and immersed into non-solvent bath. In this way finely porous UF membranes were prepared by phase inversion method. The cross sectional structure of PES membrane was asymmetric which was consist of sponge-like sublayer, finger-like toplayer, and active skin layer. From the solute rejection experiments, the molecular weight cut off of the prepared membrane in various solvent was evaluated 10,000 for DMF, 30,000 for DMAc, 50,000 for DMSO, and 10,000 for NMP respectively.

• 한국염색가공학회지
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• 제30권3호
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• pp.159-167
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• 2018

Here we designed and synthesized new zinc phthalocyanines and structures were fully confirmed by spectral and elemental analysis. All phthalocyanines have a very good solubility in industrial solvents like chloroform, dichloromethane, dimethyl sulfoxide, N,N-dimethyl formamide, propylene glycol monomethyl ether acetate (PGMEA), acetone, tetrahydrofuran and acetonitrile. UV-Visible absorption and transmittance in PGMEA showed that these dyes have suitable spectral properties for LCD color filters. By Triton X surfactant study, we confirmed that these dyes are not showing any aggregation in PGMEA. We dissolved the all phthalocyanines in LCD fabricating solvent (PGMEA), and all phthalocyanines showed more than 8 wt% of solubility. Finally, all of these results concluded that PCK1, PCK2 and PCK3 are fit for LCD green color filter.