Reduction mass spectrometry

Thermoprogrammed reduction-Mass Spectrometry experiments (TPR-MS) were performed with 1% Hi in He (total flow rate of 1.8 L.h ) in a linear temperature range of 25-1150°C (heating rate of 20°C/min) using 40 mg of catalyst introduced in a U-shaped quartz reactor and a QMS apparatus model Omnistar (Pfeiffer vacuum). 

Benzo[b]furan, 2-nitro-reduction, 4, 74, 647 Benzo[b]furan, 5-nitro-mass spectrometry, 4, 583 Benzo[b]furan, 2-(4-nitrophenyl)-properties, 4, 708 Benzo[b]furan, 2-phenyl-bromination, 4, 605 chloromethylation, 4, 607 nitration, 4, 604 photochemical reactions, 4, 636 properties, 4, 697 Benzo[b]furan, 3-phenyl-synthesis, 4, 697... 

Indolizine, 1 -cyano-2-(methylthio)-synthesis, 4, 465 Indolizine, 3,5-dialkyl-synthesis, 4, 475 Indolizine, dihydrosynthesis, 4, 467, 468 Indolizine, dimethyl-mass spectrometry, 4, 187 Indolizine, 1,2-dimethyl-oxidative dimerization, 4, 458 Indolizine, 2,6-dimethyl-cycloaddition reaction, 4, 460 reduction, 4, 459... 

Pyridinium iodide, 4,4 (l,3,4-thiadiazole-2,5-diyl)-bis(l-methyl)-reduction, 6, 564 Pyridinium ion, Af-methyl-as metabolite of pyridine, 1, 234 Pyridinium ions hydrogen bonding to water mass spectrometry, 2, 135 magnetic circular dichroism, 2, 129 NMR, 2, 121... 

In contrast, another group35 found that extracts of E. coli contained a mixture of pentulose phosphates at a concentration near 0.3 nmol per mg of the dry weight of cells. The sugars were estimated by gas chromatography-mass spectrometry after treatment of the extract with phosphatase followed by silylation, or borohydride reduction and acetylation. Furthermore, a partially purified preparation from these extracts catalyzed the synthesis of 1-deoxypentulose... 

The analyte must be converted into a volatile compound suitable for mass-spectrometric analysis. Procedures for C, N, and O follow those developed for conventional organic microanalysis— oxidation of organic C to COj, reduction of organic N to N2, and conversion of O2 into CO or COj. In most procedures, cryogenic purification of the products is carried out before mass spectrometry, and both off-line and on-line procedures have been developed. 

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