Isomer-Selective Detection of Aromatic Molecules in Temperature-Programmed Desorption for Model Catalysis.

Based on three different molecules dosed on a Pt(111) single crystal the selectivity and sensitivity of REMPI-TPD in UHV is investigated for a potential application in heterogeneous catalysis. It is shown that the two structural isomers ethylbenzene and p-xylene can be discriminated by REMPI in a standard TPD experiment. The latter is not possible for the ionization with electrons in a Q-MS.

Ethanol photocatalysis on rutile TiO2(110): the role of defects and water.

In this work we present a stoichiometric reaction mechanism for the photocatalytic ethanol oxidation on TiO2(110). The reaction products are analyzed either under reaction conditions or after irradiation at lower temperatures. Water is identified as a quantitative by-product, which resides in a defect site.

Evaluating serum alpha-tocopherol (vitamin E) in terms of a lipid ratio.

It is well known that accurate assessment of serum alpha-tocopherol requires knowledge of the serum lipids also present. Patient specimens (n = 307) within the standard reference limit of 5-18 mg/L were used to determine the following 95 percent reference interval for a lipid ratio of alpha-tocopherol to the sum of cholesterol and triglycerides [E/(C + T)]: 1.4 (1.