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Diamines having heterocyclic ring, 4,5-bis (4-aminophenyl)-2-phenyl-imidazole (BAPI), 4,5-bis(4-aminophenyl)-2-methyloxazole (BAPO) and novel diamine, 2,3-bis(4-aminophenyl)benzo[g]quinoxaline (BABQ) were prepared as curing agents for epoxy resin. Epoxy resins were obtained by curing diglycidyl ether of bisphenol A (DGEBA) with the above diamines. Properties of these DGEBA-diamine systems were studied and compared to that of DGEBA cured with commercially available diamine, 4,4′-diaminodiphenyl sulfone (DDS). On differential scanning calorimetry (DSC), the peaks of exotherms of the mixtures of DGEBA with these diamines having heterocyclic rings were observed at lower temperature and these reactions were completed in shorter time than that of DGEBA with DDS. The epoxy resins cured with these diamines containing heterocyclic ring showed excellent bonding strength even at high temperature and thermal resistance, e.g., DGEBA-BABQ gives greater bonding strengths as 35.1, 30.0, and 26.2 MPa when tested ...

This paper proposes double-rod-type jumper horns in strain assemblies with pipe jumpers for 500-kV transmission lines, the structure of which is very simple. It can be estimated that no corona discharge appears on the horns under the line voltage of 525 kV. The arc behavior on the double-rod-type jumper horns is similar to that on the single-rod-type horns. The arc can be held stably for 60 ms against strong wind (10 m/s). The stable duration increases more than 300 ms under windless condition, therefore the horns have been adopted for practical use.

New peeping prevention technology to control the viewing angle properties of TFT-LCDs has been developed. This technology can be applied to all kinds of LCDs, especially to the ones for PCs, cellular phones, ATMs and so on. In this technology, an additional LC panel in which the whole area is divided into two kinds of small visible domains of different LC alignment directions is used. The products, named VAC Filter™ or VACF™, have been put on sale in 2003 and have been applied to TOSHIBA TECRA M3 and so on.