Oxygen/carbon ratio

SV detection was also achieved to detect catecholamines on a PDMS-quartz chip. Pyrolyzed photoresist films (PPF) were used as planar carbon electrodes. Since the photoresist (AZ4330) must adhere on a substrate for pyrolysis at 1000°C, a quartz plate that could withstand high temperature was selected. The LOD of dopamine decreased from 160 nM to 100 nM when the PPF was treated by piranha solution (HjSOyHjOj). It was because such a treatment increased the surface oxygen/carbon ratio, and hence the oxidation kinetics of dopamine wave improved [765]. 

The most important operating parameters are coal concentration in the CWS, gasification temperature, gasification pressure, residence time, and oxygen/carbon ratios. These effects are discussed below. 

Figure 6. Effects of ozone exposure on oxygen/carbon ratio. Exposure curve units are ppm-min. Key , butadiene o, crosslinked butadiene and +, 75/25 butadiene/styrene random copolymer.

Figure 8. Critical surface energy as a function of oxygen carbon ratio for butadiene styrene copolymers and homopolymers after ozone exposure at 375 ppm for 150 min. Key a, crosslinked butadiene o, random copolymers and 0, block copolymers.

A series of butadiene/styrene homopolymers and copolymers were exposed to air enriched ozone for various exposure times. Evidence suggest that at least three reaction mechanisms may occur with ozone and the polymers. For butadiene and random copolymers, surface energies quickly Increase and oxygen/carbon ratios are high upon exposure. This is presumed to be simple oxidative degradation of butadiene carbon-carbon double bonds. 

A fixed bed reactor system was used to conduct the diesel ATR experiments. The reactor was operated continuously at steady state. The temperature was varied between 750 - 850 C, oxygen/carbon ratio was 0.6, steam/carbon ratio was... 

Raman and XRD are two particularly useful film characterization techniques indeed. The diamond films routinely used in our laboratory are low in surface oxygen due to the hydrogen surface termination and, consequently, are hydrophobic. X-ray photoelectron spectroscopy reveals atomic oxygen/carbon ratios of 2% or less for both as deposited micro-... 

The oxygen/carbon ratio, O/C, which is the ratio of molar oxygen flow rate multiplied by two to the molar flow rate of the fuel multiplied by the number, x, of carbon atoms in the fuel. This definition holds no matter whether there is oxygen contained in the fuel or not ... 

Outer-sphere redox mediators (see Fig. 3.23 for examples) are termed surface insensitive such that kf is not influenced by the surface oxygen-carbon ratio, surface state/cleanliness in terms of a surface coating of a monolayer film of uncharged adsorbates, or specific adsorption to surface groups/sites [1]. There is no chemical interaction or catalytic mechanism involving interaction (i.e. an adsorption step)... 

Fig. 4. Modified van Krevelen diagram after Tissot et al. (1974) showing the three major kerogen types based on their atomic hydrogen/carbon and oxygen/carbon ratios. Labeled points refer to kerogens isolated from rocks used to study organic acid generation by hydrous pyrolysis in the authors laboratory...

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