Beta carbon film

Identifying the (3 carbon states as the polymeric "beta" carbon film mentioned In the literature (6) Is less certain than assignments for a , a, and y carbon TPSR states. Rostrup-Nlelsen (6), (11) and others (25) have referred to this state on nickel catalysts as a polymeric surface carbonaceous deposit, which Includes within It a considerable amount of hydrogen. The formation of the (3 carbon state by CO exposure suggests that this film may not contain hydrogen however, there are several reasons to believe that our 3 carbon state Is a surface hydrocarbon polymeric film (1) the maximum amount of the p carbon state was produced by C2H4 decomposition at moderate temperature (573 K) (2) the (3 carbon state was only observed after TPSR In H2 of the a (or y) carbon state and In the case of CO exposure may be formed by transformation of the a or y carbon states during TPSR (3) finally, the maximum amount of the 3 carbon state was observed was 3 to 4 times the amount of CO adsorbed on freshly reduced 25 wt% Ni/AljOj... 

Compounds crystallized directly onto the carbon grid or with a defined orientation, due to other preparation methods, normally exhibit a suitable initial zone close to 0°. Samples from insoluble compounds are almost statistically oriented only biased by the particle shape. In this case, it is difficult to find a single crystalline part of appropriate thickness oriented with a suitable zone parallel to the surface. The best flexibility, and therefore the best possibility to orient a zone correctly, is given by a recently developed rotation-double tilt holder (Gatan Inc.). Through the combination of rotation and additional tilt (beta tilt) it is possible to orient the tilt axis exactly even if the crystal is not sitting flat on the support film (see Fig. 4). The tilt range, dependent on the pole piece distance of the objective lens, should be at least 40°. 

Yet, in the film containing 60% of beta-alumina, the structure shows jointed grains. Furthermore, the beta-alumina particles are not necessarily wrapped up in the glass. As in the case of sintered material, these films react in the presence of CO2 and water vapor. This causes the apparition of inflorescences we can thus assume the formation of sodium carbonate. 

Electrochemical stability at over 4 V is key property high purity solution casting ability to cast thin electrodes from very high (>80%) carbon formulations Orientation under high electrical fields of the beta crystallites in thin films achieves high sensitivity to changes in shape because of pressure (piezo) or temperature (pyro). Considered a ferroelectric material because the remnant polarization is stable. Piezo film for active cancellation of noise in sound absorbing foam laminate... 

Carbon 14 n (radiocarbon) Radioactive carbon of mass number 14, naturally occurring bur usually made by irradiating calcium nitrate. It has been used as a beta-ray source in gages for measuring the thickness of plastics films (Smith MB, March J (2001) Advanced organic chemistry, 5th edn. Wiley, New York). 

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