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A series of new, fluorinated poly(imide-amide-su1fone)s has been synthesized by solution polycondensation of aromatic diamines containing sulfone groups with diacid chlorides incorporating both imide and hexafluoroisopropylidene units. These polymers are soluble in polar amidic solvents, and their solutions can be cast into colorless, thin, flexible films having good electrical insulating properties and high thermal stability. The dielectric constant value is 3.49-3.68. The decomposition temperature in air is 464-479"C, and the glass transition temperature is in the range 279-359°C. All these characteristics have been discussed and compared with those of related fluorinated poly(imide-amide)s which do not contain sulfone groups and with other imide polymers without hexafluoroisopropylidene units.

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Microstructures and electrical properties of lead zirconate titanate (PZT) thick films made by using a screen-printing laser transfer method have been studied. The PZT thick-film elements were first screen printed on a sapphire substrate and sintered at 1150to1250°C. Then they were bonded to a target substrate such as silicon and released from the sapphire by means of an excimer laser exposure from the backside of the sapphire substrate. This approach makes it possible to obtain highly densified films because there is less limitation on sintering conditions, and allows integrating patterned PZT thick films onto many kinds of substrates. The thick films have dielectric constants of 1397 to 1675, remnant polarization of 32to35μC∕cm2, a piezoelectric constant d31 of about −124pm∕V, and Young’s modulus Y11E(59.4GPa) of almost the same as the corresponding bulk ceramic.

The authors have constructed an array of 12 piezoelectric ejectors for printing biological materials. A single-ejector footprint is 8 mm in diameter, standing 4 mm high with 2 reservoirs totaling 76 µL. These ejectors have been tested by dispensing various fluids in several environmental conditions. Reliable drop ejection can be expected in both humidity-controlled and ambient environments over extended periods of time and in hot and cold room temperatures. In a prototype system, 12 ejectors are arranged in a rack, together with an X-Y stage, to allow printing any pattern desired. Printed arrays of features are created with a biological solution containing bovine serum albumin-conjugated oligonucleotides, dye, and salty buffer. This ejector system is designed for the ultra-high-throughput generation of arrays on a variety of surfaces. These single or racked ejectors could be used as long-term storage vessels for materials such as small molecules, nucleic acids, proteins, or cell libraries, which would allow for efficient preprogrammed selection of individual clones and greatly reduce the chance of cross-contamination and loss due to transfer. A new generation of design ideas includes plastic injection-molded ejectors that are inexpensive and disposable and handheld personal pipettes for liquid transfer in the nanoliter regime. (Journal of Biomolecular Screening 2004:85-94)