Mass direct screening

Nordgren HK, Beck O. 2003. Direct screening of urine for MDMA and MDA by liquid chromatography-tandem mass spectrometry. J Anal Toxicol 27 15. 

Roulsen, S.-A. Direct screening of a dynamic combinatorial library using mass spectrometry. J. Am. Soc. Mass Spectrom. 2006,17, 1074-1080. 

ESI-MS/MS using an FT-ICR mass spectrometer also enables direct screening of dynamic combinatorial library (DCL) [106]. The protein-Ugand complexes are selectively trapped and dissociated to facilitate selective identification of the DCL ligands. 

Politi L, Morini L, Polettini A. A direct screening procedure for diuretics in human urine by liquid chromatography—tandem mass spectrometry with information dependent acquisition. Clin Chim Acta 2007 386 46-52. 

Pena, R, Cdrdenas, S., Gallego, M. and Valcarcel, M., Direct screening of olive oil samples for residual benzene hydrocarbon compounds by headspace-mass spectrometry. Anal. Chim. Acta, 526, 77-82 (2004). 

The three signals are fed into an oscilloscope as vertical-, horizontal-, and external-intensity marker input. The keyphazor appears as a bright spot on the screen. In cases where the orbit obtained is completely circular, the maximum amplitude of vibration occurs in the direction of the keyphazor. To estimate the magnitude of the correction mass, a trial-and-error process is initiated. With the rotor perfectly balanced, the orbit finally shrinks to a... 

Provided that the catalyst is active enough, there will be sufficient conversion of the pollutant gases through the pellet bed and the screen bed. The Sherwood number of CO is almost equal to the Nusselt number, and 2.6% of the inlet CO will not be converted in the monolith. The diffusion coefficient of benzene is somewhat smaller, and 10% of the inlet benzene is not converted in the monolith, no matter how active is the catalyst. This mass transfer limitation can be easily avoided by forcing the streams to change flow direction at the cost of some increased pressure drop. These calculations are comparable with the data in Fig. 22, taken from Carlson 112). 

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