• Fibers and Polymers
• /
• v.7 no.1
• /
• pp.30-35
• /
• 2006

The influences of a series of new azo direct dyes including copper-complexes based on benzidine congeners, 2,2'-dimethyl-5,5'-dipropoxybenzidine and 5,5'-dipropoxybenzidine, were examined using microorganism, Daphnia magna. The purpose of the research described in this paper was to use bioassays with daphnids to determine the aquatic toxicity of new azo dyes in which copper was incorporated. The results clearly show that copper has negative effects to aquatic ecosystem as expected. The study also suggested that the assay with Daphnia magna was an excellent method to evaluate the influences of dyes to the aquatic environment.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.5
• /
• pp.948-952
• /
• 2008

The molecular association of acceptors with electron donors is studied in the highly-polar solvent $CH_3CN$. Tetracyanoquinodimethane (TCNQ) forms a stable charge-transfer complex with donor molecules such as 4- aminobiphenyl (4-AB), benzidine (BD) and 2-aminobiphenyl (2-AB) with high association constants. The complexes of TCNQ with 4-AB or BD show new absorption bands at around 800 and 500 nm, which can be identified as reduced $TCNQ^{{\bullet}-}$ and $TCNQ^{2-}$ species, respectively. These bands grow quickly upon photoirradiation, implying that the charge-transfer complexes are easily formed in an excited state. Conversely, a small spectral manifestation of the charge transfer was observed in the case of 2-AB complex. It is demonstrated that the structural orientation between the geminate ion pairs could play an important role in building a stable complex.

• Mycobiology
• /
• v.35 no.2
• /
• pp.65-68
• /
• 2007

Three novel complexes of Cu(II), Co(II) and Zn(II) using a macrocyclic ligand derived by the condensation of diethylphthalate and benzidine have been designed, synthesized and characterized by UV-Vis., IR, Mass and Elemental analyses data in order to find out their antifungal activities. The stoichiometry of the complexes has been found to be 1:1 (Metal: Ligand). The analytical data indicate that the complexes exhibit square-planar geometry. The antifungal activity of the macrocyclic ligand and its metal complexes has been screened in vitro against fungi such as Aspergillus niger, A. flavus, Trichoderma harizanum, T. viridae and Rhizoctonia solani.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.11 no.2
• /
• pp.118-125
• /
• 2001

Recently, biochemical analysis using hemoglobin adduct is frequently performed to evaluate the exposure to chemical carcinogens. However, data on the effect of co-exposure with other chemicals on hemoglobin adduct formation are seldom provided. The objective of this study is to evaluate the effects of pretreatment of ethanol(EtOH) and phenobarbital(PB), which are known to affect metabolism of xenobiotics, on the formation of hemoglobin adducts in the rats(Sprague-Dawley) administered benzidine(BZ). The experimental rats were divided into control, EtOH, and P8 groups. Rats were pretreated with EtOH or PB 24 hours before the oral administration of BZ. Blood sampling was taken before the administration of the chemicals and 0.5, 3, 6, 9, 12, 24, 48, 72, 96, and 144 hours after the administration of the BZ in 5 rats each. The blood was separated into hemoglobin and plasma immediately after taking the blood samples, and the adducts were undergone basic hydrolysis to convert them into aromatic amines. Hydrolyzed BZ, monoacetylbenzidine (MABZ), and 4-aminobiphenyl(4ABP) were separated by reversed-phase liquid chromatography without derivatization, and quantitative analyses of them were performed by a highperformance liquid chromatograph equipped with electrochemical detector. The quantitative amount of the metabolites was expressed by hemoglobin binding index(HBI), BZ-, MABZ-, and 4ABP-HBI of EtOH and PB groups were increased more than those of control group. These results are attributable to the fact that EtOH and PB induced N-hydroxylation related to the hemoglobin adduct formation. The ratio of N-acetylation (viz, MABZ-HBI/BZ-HBI) showed no significant difference between EtOH group and control group. It means that EtOH increased N-hydroxylation and N-acetylation in a similar degree. The N-acetylation ratio of PB group was relatively lower than control group because the PB increased N-hydroxylation induction. The N-acetylation ratios of all groups were higher than 1 during the entire experimental period. This result suggests that the effects of EtOH or PB need to be considered in the biochemical monitoring for the assessment of intermittent exposure of benzidine.

• Polymer(Korea)
• /
• v.39 no.2
• /
• pp.275-280
• /
• 2015

Two series of copolyimides (Co-PIs) were prepared by reacting 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and 1,2,4,5-benzentetra carboxylic dianhydride (pyromellitic dianhydride) (PMDA), as dianhydrides based on 4,4'-biphthalic anhydride (BPA) and 2,2'-bis(trifluoromethyl)benzidine (TFB) by using thermal- and chemical imidizations. Co-PIs films with different dianhydride monomer compositions were compared in terms of their thermal properties and optical transparencies. The addition of PMDA was more effective than the addition of 6FDA for improving the thermal properties. Meanwhile, 6FDA is more effective in optical transparencies.

• Journal of the Korean Chemical Society
• /
• v.31 no.6
• /
• pp.590-600
• /
• 1987

Silicone-containing polyamide-imides were prepared from bis(p-chlorocarbonylphenyl)diphenylsilane (BCCDPS), pyromellitic dianhydride(PMDA) and diamines. The thermal characteristics of the above polymers had been carefully studied using a thermogravimetric analyzer. The thermal stability of polymer was decreased with increasing contents of bis(p-carbonylphenyl)diphenylsilane units(BCDPS). The effect of diamine on thermal stability of polymer led benzidine > m-phenylenediamine> 4,4'-diaminodiphenyl ether > 4,4'-diaminodiphenyl sulfone. The activation energy of degradation of polymer obtained by Friedman method increased as the contents of BCDPS in the polymer decreased. The degradation temperature of polymers generally increased as the activation energy increased. The solubility of polymer increased as the content of BCDPS increased except polymers prepared with benzidine.

• Journal of the Korean Applied Science and Technology
• /
• v.19 no.2
• /
• pp.73-78
• /
• 2002

The polyimide(PI) Langmuir-Blodgett(LB) ultra thin films were prepared by imidizing the PAAS LB films of PMDA and benzidine system with a thermal treatment at $250^{\circ}C$ for 30min, where the PAAS LB films were formed on substrates by using LB technique. The thicknesses of one layer of PAAS and PI LB film that deposited at the surface pressure of 27mN/m were 20.9 and 4A, respectively. At low electric field, ohmic conduction($I^{\propto}$ V) was observed and the calculated electrical conductivity was about $4.23{\times}10^{-15}{\sim}9.81{\times}10^{-15}S/cm$. The dielectric constant of LB film was about 7.0.

• Journal of the Korean Applied Science and Technology
• /
• v.16 no.4
• /
• pp.307-311
• /
• 1999

Interfacial properties of electrode and organic thin layer is one of the most important factor in performing a Light Emitting Diodes(LED). Phthalocyanine copper was used as a buffer layer to improve interface characteristic, so that device efficiency was improved. In this study, LEDs were fabricated as like structures of Indium-Tin-Oxide (ITO) / N,N' -Diphenyl-N,N'-di(m-tolyl)-benzidine (TPD) / 8-Hydroxyquinoline aluminum(Alq) / Aluminum(Al) and Indium-Tin-Oxide(ITO) / N,N'-Diphenyl-N,N' -di(m-tolyl)-benzidine(TPD) / 2-(4-Biphenylyl)-5(4-tert-butyl-phenyl)-1,3,4-oxadiazole(PBD) / Aluminum(Al). In these devices, CuPC was layered at electrode/organic layer interface. As position is changing and thickness is changing, devices showed characteristic luminescence efficiency and luminescence inensity respectively. We showed in this study that luminescence efficiency was improved with CuPC layer in LEDs. The efficiency of device with layer CuPC is higher than that of 2 layer CuPC. However, the luminescence of 2 layer CuPC device got higher value.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.10 no.1
• /
• pp.1-17
• /
• 2000

Carcinogen-DNA adduct analysis has potential for biomonitoring the earliest effects of exposure to many chemical carcinogens. They are the covalent reaction products of electrophiles and nucleophilic sites on DNA and the initial damage to DNA induced by many carcinogens. So many researchers begin to use them as biomarker for monitoring the earliest exposure of carcinogens and develop the effective analytical techniques about them. Randerath, Gupta and coworkers(1981, 1982) has also developed a $^{32}P$-postlabelling method as one among them. A major project for biomonitoring workers with carcinogen-DNA adducts is to develop non-invasive samples instead of tissues of target organs such as baldder and lung. This study use the exfoliated urothelial cells in urine for examine benzidine-DNA adducts. The content of exfoliated urothelial cells is not enough to significantly measure DNA content with spectrophotometer, and require the another way. So firstly washing the collected cells with PBS and 70% ethanol and centrifuge them for removing the crystals in urine, which block the isolation of DNA adducts. And then, measure the total nucleotide after $^{32}P$-postlabelling for calculating RAL. $[{\gamma}-^{32}P]ATP$ using for $^{32}P$-postlabelling, can synthesize with $[^{32}P]H_3PO_4$, and reagent and enzyme mixture (RM, EM), which is very economic in case of requiring a lot of them. Chromatography was composed of two steps. First step was to separate adduct ones from unadducted nucleotide, and secondary step was separate each adduct, which were performed with 4 kinds of solvents and different directions on TLC. With this procedure, we measure the DNA adducts in exfoliated urothelial cells of workers who were employed in benzidine and benzidine-dye company. RAL of adducts were $89.0{\times}10^7$ and $57.0{\times}10^7$ in them. In conclusion, we can significantly measure the DNA adduct in exfoliated urothelial cells by using the above $^{32}P$-postlabelling procedures, and use them to be biomonitoring workers who exposed carcinogens.

• Journal of Environmental Health Sciences
• /
• v.4 no.1
• /
• pp.34-36
• /
• 1977

In the examination of leucocyte peroxidase reaction, almost methods were used by benzidine, but it was becoming clear carcinogen. In this study was carried out by comparative Osgood and Asworth method with modified Kaplow method by use of 3-amino-9-ethyl carbasol, In the result, Osgood and Asworth method and new modified Kaplow method in the periperal blood cells (r=0.957) and bone marrow cells (r=0.972) were high correlation.