Inference from trapped

Many reviews have been written recently on the subject of germenes and they have been the subject of numerous computational studies. In the absence of sterically bulky ligands, germenes rapidly dimerize or react with available substrates. For this reason, germenes are frequently studied as transient, reactive intermediates isolated in a matrix,or inferred from trapping reactions. 

Severinghaus J. P. and Brook E. (1999) Simultaneous tropical-Arctic abrupt climate change at the end of the last glacial period inferred from trapped air in polar ice. Science 286, 930-934. 

The existence of n-complex intermediates can be inferred from experiments in which they are trapped by nucleophiles under special circumstances. For example, treatment of the acid 1 with bromine gives the cyclohexadienyl lactone 2. This product results from capture of the n-complex by intramolecular nucleophilic attack by the carboxylate group ... 

The electrical current of a coplanar interdigilal gold/LPPP/gold device is space charge limited due to p-type charge earner traps localized in the bandgap [28]. This can be inferred from the field dependence of the dark current at room temperature. The thermally stimulated current spectrum exhibits two peaks, corresponding to two distinct trap levels ,1 and ,", which can be calculated from the rise in current, /, below the peak temperature ... 

This chapter deals with systems in which a product of one reaction becomes a reactant in the next. The intervening species, known as an intermediate, sometimes rises to a concentration comparable to those of the main species, the reactants and products. In other circumstances, it remains at a much smaller concentration. Whether at high concentration or low, the intermediate may be directly detectable. If not, its existence can perhaps be inferred from the kinetic equations or trapping experiments. 

Much of the geographic variability in sedimentary ( Paxs/ °Thxs) observed in modern sediments may be explained by variability in the composition of biogenic particles arising from variability in the structure of the planktonic ecosystem. This can be inferred from the composition-dependence of F(Th/Pa) (Fig. 8), and is shown explicitly by the relationship between sediment trap ( Paxs/ °Thxs) and the opal/calcite ratio of the trapped particles (Fig. 9). Sediment trap ( Paxs/ °Thxs) also exhibits a positive relationship with the mass flux of particles, but the correlation is poorer than that with particle composition (Fig. 9). Indeed, the relationship between particulate ( Paxs/ °Thxs)... 

In conclusion, the reversibility of bromonium ion formation is at present inferred from particular experiments only nothing allows us to conclude that this mechanistic feature is general. However, when nucleophilic trapping... 

A representative example for the information extracted from a TRMC experiment is the work of Prins et al. [141] on the electron and hole dynamics on isolated chains of solution-processable poly(thienylenevinylene) (PTV) derivatives in dilute solution. The mobility of both electrons and holes as well as the kinetics of their bimolecular recombination have been monitored by a 34-GHz microwave field. It was found that at room temperature both electrons and holes have high intrachain mobilities of fi = 0.23 0.04 cm A s and = 0.38 0.02 cm / V s V The electrons become trapped at defects or impurities within 4 ps while no trapping was observed for holes. The essential results are (1) that the trap-free mobilities of electrons and holes are comparable and (2) that the intra-chain hole mobility in PTV is about three orders of magnitude larger than the macroscopic hole mobility measured in PTV devices [142]. This proves that the mobilities inferred from ToF and FET experiments are limited by inter-chain hopping, in addition to possible trapping events. It also confirms the notion that there is no reason why electron and hole mobilities should be principally different. The fact... 

Electron attachment rates have been measured for numerous solutes. Many of these studies were limited to three solvents cyclohexane, 2,2,4-trimethylpentane, and tetrame-thylsilane (TMS), and those rates are discussed here. What to expect in other liquids can be inferred from these results. Considerable insight has been gained into certain reactions. Equilibrium reactions of electrons are particularly interesting since they provide information not only on energy levels, as mentioned above, but also on the partial molar volume of trapped electrons. This has led to a better understanding of the mechanism of electron transport. 

The intermediacy of a 4-imino- 1,2-oxathietane 2-oxide from the addition of sulfur dioxide to ketenimines was inferred from the trapping with methanol. The final isolated product in absence of methanol, l,2-thiazetidin-3-one 1-oxide, was established by X-ray (Scheme 42) (81CC350). 

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