187.
    发明专利
    未知

    公开(公告)号:DE69814035T2

    公开(公告)日:2003-10-23

    申请号:DE69814035

    申请日:1998-10-02

    Abstract: A method and apparatus for measuring properties of a liquid composition includes a mechanical resonator, such as a thickness shear mode resonator or a tuning fork resonator, connected to a measurement circuit. The measurement circuit provides a variable frequency input signal to the tuning fork, causing the mechanical resonator to oscillate. To test the properties of a liquid composition, the mechanical resonator is placed inside a sample well containing a small amount of the liquid. The input signal is then sent to the mechanical resonator and swept over a selected frequency range, preferably less than 1 MHz to prevent the liquid being tested from exhibiting gel-like characteristics and causing false readings. The mechanical resonator's response over the frequency range depends on various characteristics of the liquid being tested, such as the temperature, viscosity, and other physical properties. Particular mechanical resonators, such as tuning fork resonators, can also be used to measure a liquid composition's electrical properties, such as the dielectric constant and conductivity, because the tuning fork's structure allows a high degree of electrical coupling between the tuning fork and the surrounding liquid. The mechanical resonator can be covered with a coating to impart additional special detection properties to the resonator, and multiple resonators can be attached together as a single sensor to obtain multiple frequency responses. The invention is particularly suitable for combinatorial chemistry applications, which require rapid analysis of chemical properties for screening.

    COMPOSICIONES QUE COMPRENDEN NIQUEL Y SU USO COMO CATALIZADORES EN LA DESHIDROGENACION OXIDANXTE DE ALCANOS.

    公开(公告)号:MXPA01008496A

    公开(公告)日:2003-06-06

    申请号:MXPA01008496

    申请日:2000-02-22

    Inventor: LIU YUMIN

    Abstract: Se divulgan catalizadores y metodos para la oxideshidrogenacion de alcanos. Los catalizadores de la invencion comprenden generalmente (i) niquel o bien un compuesto que contiene niquel y (ii) por lo menos uno o varios de los siguientes: titanio (Ti), tantalio (Ta), niobio (Nb), cobalto (Co), hafnio (Hf), tungsteno (W), itrio (Y), zinc (Zn), zirconio (Zr), o aluminio (Al) o bien un compuesto que contiene uno o varios de estos elementos. En modalidades preferidas, el catalizador es un catalizador soportado, el alcano se selecciona dentro del grupo que consiste de: etano, propano, isopropano, isobutano, n-butano y cloruro de etilo, se alimenta conjuntamente oxigeno molecular con el alcano a una zona de reaccion mantenida a una temperatura que se ubica dentro de un rango de aproximadamente 250oC a aproximadamente 350oC, y el etano es deshidrogenado de manera oxidante para formar el alqueno correspondiente con una conversion de alcano de por lo menos aproximadamente 10% y una selectividad de alqueno de por lo menos aproximadamente 70%.

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