• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.13-19
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• 1998

Copolyimide membranes of different chemical structure based on pyromellitic dianhydride (PMDA)/methylendianiline(MDA) were prepared by varying their chemical compositions with adding meta-phenylendiamine (MPD), para- phenylendiamine (PPD), 2,4,6- trimethyl-1,3-phenylenediamine(TriMeMPD) as a co-monomer. The $N_2$ and $O_2$ permeation properties are qualitatively correlated to specific free volume and intersegmental distance of membrane. The partial replacement of MDA with MPD or PPD caused in the PMDA/MDA based membranes increase in density, and decrease in free volume, d-spacing, consequently resulted in decreased permeability coefficient. In the case of TriMeMPD, opposite results were observed. In all membranes, the permeability coefficients were pressure independent, and membranes which have high permeability coefficient showed low $N_2/O_2$ ideal separation factor as an usual manner. The permeability coefficient also increased with temperature and $N_2/O_2$ ideal separation factor decreased. The increase ratio of the $N_2$ permeability coefficient was larger than that of $O_2$.

• The Korean Journal of Pharmacology
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• v.26 no.1
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• pp.67-76
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• 1990

Hydrocortisone 50 mg/kg (HC), dehydroepiandrosterone 250 mg/kg (DHEA), ${\beta}-estradiol$ 5 mg/kg (E2), and testosterone 20 mg/kg (TS) were subcutaneously injected into the castrated ICR mice at noon for four days, and the animals were sacrificed at 10-12 A.M. of the fifth day. The intestinal DAO activity was significantly decreased by HC, but it was rather increased by E2 and TS, respectively. And DHEA did not change the DAO activity. But the hepatic MAO activity was not affected by anyone of HC, DHEA, E2, and TS. Aminoguanidine 25 mg/kg produced the marked decrease of the intestinal DAO activity and the significant increases of the intestinal PT and SD contents, but it did not change the hepatic polyamine contents. HC and DHEA induced the significant increase of the intestinal PT content. E2 induced the marked increase of the hepatic PT content and the moderate increase of the intestinal PT content. TS little affected the polyamine contents of the liver and intestine. These results suggest that the E2-induced increase of the hepatic PT content is rather ascribed to the greater enhancement of PT synthesis than the inhibition of polyamine catabolism, and that the HC-induced increase of the intestinal PT content is due partly to the inhibition of polyamine catabolism via DAO.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.110-117
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• 1995

Tc-99m Labeled hexamethylenepropyleneamineoxime ([$^{99m}Tc$]-HMPAO) is a famous amino-oxime compound and is widely used to construct SPECT images of cerebral blood flow. To investigate the relationship between chemical structure and radiolabeling in these kind of diamine-oxime compounds, we synthesized seven compounds by Schiff's base formation and successive reduction with sodium borohydride. They were (RR/SS )-4,8-diaza-3,6,6,9-tetramethylundecane-2,10-dione bisoxime (2), (RR/SS/meso)-4,8-diaza-3,9-dimethy-lundecane-2,10-dione bisoxime (4), (RR/SS/meso)-4,8-diaza-3,10-dimethyldodecane-2,11-dione bisoxime (5), (RR/SS/meso)-4,7-diaza-3,6,6,8-tetramethyldecane-2,9-dione bisoxime (8), (RR/SS/meso)-4,7-diaza-5,6-cyclohexyl-3,8-dimethyldecane-2,9-dione bisoxime (10), (RR/SS/meso)-3,4-bis(1-aza-2-methyl-3-oxime-1-butyl)-benzoic acid (12), and (RR/SS/ meso)-2,3-bis(1-aza-2-methyl-3-oxime-1-butyl) benzophenone (14). Chemical structures of all the synthesized compounds were identified by taking $^1H$ spectrum. Among them, 2 and 4 are propyleneamine oxime (PnAO), 6 is butyleneamine oxime (BnAO) and 8, 10, 12 and 14 are ethyleneamine oxime (EnAO). Each compound (0.5 mg) was incubated with stannous chloride (0.5 g - 8 g), carbonate-bicarbonate buffer (final concentration = 0.1 M, pH 7 - pH 10) and Tc-99m-pertechenate (1 ml). Tc-99m labeling of these compounds were checked by ITLC (acetone), ITLC (normal saline), reverse phase TLC (50 % acetonitrile) and ITLC (ethyl acetate). According to the results, EnAO's were not labeled by Tc-99m in any of above condition. About 11 % of maximum labeling efficiency was obtained with BnAO. However, 4 (PnAO) was labeled with Tc-99m to 85 % which is similar to the labeling efficiency of 2 (HMPAO). Hydrophilic impurity (9 % ) was the most significant problem with the labeling of 4, however, pertechnetate (3 % ) and colloid (3 %) were minor problem. In conclusion, we synthesized seven diamine blsoxlme compounds. Among them, four EnAO compounds were not labeled by Tc-99m. A BnAO was labeled poorly and two PnAO's were labeled well. These labeling can be explained by tertiary structure of their Tc-99m chelate.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.1 s.38
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• pp.51-55
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• 2006

The green emitting high performance OLEDs using the $Alq_3$-C545T fluorescent system have been fabricated and characterized. In the device fabrication, 2-TNATA [4,4',4'-tris(2-naphthylphenyl-phenylamino)-triphenylamine] as a hole injection material and NPB [N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine] as a hole transport material were deposited on the ITO(indium thin oxide)/glass substrate by vacuum evaporation. And then, green color emission layer was deposited using $Alq_3$ as a host material and C-545T[10-(2-benzothiazolyl)-1,1,7,7- tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1]/benzopyrano[6,7,8-ij]-quinolizin-11-one] as a dopant. Finally, small molecule OLEDs with structure of ITO/2-TNATA/NPB/$Alq_3$:C545T/$Alq_3$/LiF/Al were obtained by in-situ deposition of $Alq_3$, LiF and Al as the electron transport material, electron injection material and cathode, respectively. Green OLEDs fabricated in our experiments showed the color coordinate of CIE(0.29, 0.65) and the maximum power efficiency of 7.3 lm/W at 12 V with the peak emission wavelength of 521 nm.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.885-886
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• 2003

A bilayer is used as an anode electrode for organic electroluminescent devices. The bilayer consist of an ultrathjn ZnO layer adjacent to an hole-transporting layer and an Indium tin oxide(ITO) outerlayer. We tried to bring low the barrier between the devices as deposited ZnO films on ITO substrates. We fabricated the organic EL structure consisted of Al as cathode, $Al_{2}O_{3}$ as electro transport layer, Alq3 as luminously layer, triphenyl diamine(TPD) as hole transport layer and ZnO(l nm )/ITO(l50 nm) as anode. The result of this experiment was not good compared with the case of using ITO, Nevertheless, at this structure we obtained the lowest turn-on voltage as the value of 19 V and the good brightness (6200 $cd/m^{2}$) of the emission light from the devices. Then the quantum efficiency was to be 1.0%.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.147.2-147.2
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• 2014

Organic Light Emitting Diode (OLED)에 사용되는 유기재료 N,N.-diphenyl-N,N.-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine(NPB)의 상전이 특성을 여러 진공도에서 평가하였다. 압력, 온도제어가 가능한 진공시스템을 사용하여 여러 진공도에서 NPB의 상전이 온도를 측정하였고, 본 연구에 사용된 진공시스템의 신뢰성을 검증하기 위해 상압에서 측정한 NPB의 melting temperature를 Differential Scanning Calorimetry(DSC) data와 비교하였다. 또한 각 압력($10^{-7}{\sim}760Torr$)에서 측정한 상전이 온도를 바탕으로 최종 결과물인 NPB의 Phase diagram을 얻어냄으로써 일정 압력, 일정 온도에서의 NPB의 상거동을 예측할 수 있었다. 이러한 결과는 기존의 DSC열분석으로는 확인하기 어려웠던 진공에서의 유기재료의 상전이를 관측하였다는데 큰 의미가 있다. 향후, 이러한 방법을 활용한 진공에서의 유기재료의 상전이 특성 관측은 유기재료를 이용한 진공 증착공정방법의 최적화와, 다양한 유기재료의 열안정성 특성 파악에 도움이 될 것으로 기대가 된다.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.1878-1880
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• 2005

In this research, We investigated the effect of $O_2/O_3$ Plasma treatment of indium-tin oxide (ITO) surface on the performance of organic light emitting devices (OLEDs). The OLED had a structure of ITO/N,N'-diphenyl-N,N' -(3-methylphenyl)-1, 1'-biphenyl-4-4'-diamine (TPD)/Tris (8-hydroxyquinolinato) Aluminum $(Alq_3)/Al$. The ITO surface was treated by $O_2/O_3$ plasma with different RF power chamber pressure and exposure time. As a result, the emission efficiency of the OLEDs could be improved obviously.

• Journal of the Korean Society of Clothing and Textiles
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• v.4 no.1_2
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• pp.19-24
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• 1980

To study possible modification of acrylic fiber, Cashmilon SF was treated with hexamethylene-diamine(HMDA) in toluene at elevated temperature. Physico-chemical properties of treated fiber were tested by dyeing with benzyl scarlet BS and by measuring tensile strength of the fiber. Following results were obtained from this experiment. 1) HMDA and fiber were condensed at above $120^{\circ}C$. 2) Treated samples could be dyed with acidic dyes. 3) Treatment with HMDA decreased tensile strength of the fiber. This study therefore suggests that HMDA can be used to modify the properties of the fiber.

• Bulletin of the Korean Chemical Society
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• v.17 no.8
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• pp.688-693
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• 1996

Tetradentate Schiff base ligands derived from 2-hydroxy-1-naphthaldehyde and aliphatic diamine have been synthesized. Cu(Ⅱ) complexes of Schiff base ligands have been synthesized from the free ligands and copper acetate. The mole ratio of ligand to copper was identified to be 1:1 by the result of elemental analysis and Cu(Ⅱ) complexes were in a four-coordinated configuration. The electrochemical redox process of Cu(Ⅱ) complexes in a DMF solution has been investigated by cyclic voltammetry, chronoamperometry, differential pulse voltammetry, and controlled potential coulometry. The redox process of Cu(Ⅱ) complexes is one electron transfer process in quasi-reversible and diffusion-controlled reaction. The electrochemical redox potentials and the kinetic parameters of Cu(Ⅱ) complexes are affected by the chelate ring of Schiff base ligands.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.145.2-145.2
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• 2003

We have developed a silver staining method using a dye as a silver sensitizer. Dye staining is performed in combination with silver nitrate staining. Dye-silver staining shortens the time of silver staining (~1 hr) and improves the sensitivity better than that of silver diamine stain (1-10 ng) or comparable to that of silver nitrate stain with glutaraldehyde as a silver sensitizer. In dye staining (silver sensitizing step), it has been proven that the sensitivity is at least 4 times comparing with that of CBBR stain and staining time is about 45 min. (omitted)