Controlled reactions, vibrational analysis

This lineshape analysis also implies tliat electron-transfer rates should be vibrational-state dependent, which has been observed experimentally [44]- Spin-orbit relaxation has also been identified as an important factor in controlling tire identity of botli electron and vibrational-state distributions in radiationless ET reactions. 

Biophysical characterization showed that a single HRP II protein bound 17 molecules of heme [35]. In an in vitro heme polymerization assay, HRP II promoted the synthesis of hemozoin, while controls, such as the proteins bovine serum albumin and lysozyme or the homopeptides polyhistidine, polylysine, and polyasparagine, did not. FT-IR analysis of the reaction product showed the characteristic vibrations of hemozoin. The polymerization activity had a pH maximum near 4.0, which dropped off precipitously near the pKa of histidine. The heme polymerization... 

The hydrochlorination of silicon was carried out in a test device consisting of feed supply, reactor, and product analysis. The reactor is made of glass and has an internal diameter of 35 mm. HCl feed is introduced to the silicon powder through a glass frit bottom of the reactor. The reaction temperature was controlled by a furnace with temperature controller and measured by a thermocouple inserted into an indent on the side of the reactor, reaching to the silicon bed. To adapt the conditions to the industrial fluidized bed reactor, the glass reactor was forced to vibrate by a commercial excentric drive. 

FT-IR monitoring has been used to monitor the initiation of Grignard reactions [90]. Sampling and off-line analysis of these reactions are problematic since the Grignard is moisture sensitive. On-line monitoring allows the point of initiation and the subsequent formation of the Grignard to be monitored via the R-Mg-X vibration and means that the halide addition to be controlled on a plant scale, thus avoiding potential safety issues. 

Heinz W. Siesler is a professor of physical chemistry at the Univereity of Duisbui -Essen, Germany, since 1987. His main research interests focus on the application of vibrational spectroscopy to chemical and polymer research, analysis, and quality/reaction control. He has written more than 200 publications (including three monographs) in this field of research and presented more than 250 lectures worldwide. He received the 1994 EAS Award, the 2000 Tomas Hirschfeld Award, and the 2003 Buechi Award in near-infrared spectroscopy. 

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