Oxygen sensing tests

In addition to the method described above, there are at present, on the market, several glucose analyzers offered by several commercial companies, wherein the individual injects approximately 20 microliters of serum. This is then incubated with glucose oxidase and the peroxide or oxygen generated is measured with an oxygen sensing electrode. These instruments cannot perform the test on 1 xl nor are they designed for that purpose at the present time. 

Current research and development efforts have focused on the use of more biocompatible coatings to reduce the biological response of both intravascular and subcutaneous devices. These efforts are based on the expectation that such developments wfllbe critical to the ultimate success in developing implanted sensors that yield continuous analytical results that match closely with conventional in vitro test methods. One new approach in this direction employs novel nitric oxide (NO) release polymers to coat the surface of intravascular sensors.The potent antiplatelet activity of NO has been shown to greatly reduce the formation of thrombus on the surface of implantable electrochemical oxygen sensing catheters, and yield much more accurate continuous PO2 values in animal experiments. 

The oxygen-sensing properties of sensors based on the AljOj-ZrOj-YjOj eutectic composites and polycrystalline zirconia sensors with the same Y2O3 concentration in the electrolyte were also investigated [53]. All tests were carried out using nitrogen as a carrier gas. In all measurements, the airflow rate was -100 cmVmin. The oxygensensing properties of sensors based on the polycrystalline AljOj-ZrOj-YjOj solid electrolyte were shown for comparison. 

Of the many tests which have been submitted, the determination of active oxygen or peroxide content seems to give rather good correlation of data. During the oxidation of fat, certain oxygen-containing compounds are formed which are active in the sense that they are capable of liberating iodine from potassium iodide (19). The liberated iodine may be determined quantitatively and it thus becomes a measure of rancidity. 

This presentation reports some studies on the materials and catalysis for solid oxide fuel cell (SOFC) in the author s laboratory and tries to offer some thoughts on related problems. The basic materials of SOFC are cathode, electrolyte, and anode materials, which are composed to form the membrane-electrode assembly, which then forms the unit cell for test. The cathode material is most important in the sense that most polarization is within the cathode layer. The electrolyte membrane should be as thin as possible and also posses as high an oxygen-ion conductivity as possible. The anode material should be able to deal with the carbon deposition problem especially when methane is used as the fuel. 

Just as a relationship exists between the various properties of petroleum with parameters such as depth of burial of the reservoir (Speight, 1999), similar relationships exist for the properties of coal (e.g., Solomon, 1981 Speight, 1994). Variations in hydrogen content with carbon content or oxygen content with carbon content and with each other have also been noted. However, it should be noted that many of the published reports cite the variation of analytical data or test results not with rank in the true sense of the word but with elemental carbon content that can only be approximately equated to rank. 

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