Charge atomic spectroscopy

Beyond atomic spectroscopy muonium renders the possibility to search directly and sensitively for yet unknown interactions between the two charged leptons from two different generations. Among the mysteries observed for leptons are the apparently conserved lepton numbers. As a matter of fact, several distinctively different lepton number conservation schemes appear to hold, some of which are additive and some are multiplicative, parity-like. Some of them distinguish between lepton families and others don t [46,47,48,49,50]. No local gauge invariance has been revealed yet which would be associated with any of these empirically established laws. Since there is common believe [51] that any discrete conserved quantity is connected to a local gauge invariance, a breakdown of lepton number conservation is widely expected, particularly in the framework of many speculative models. 

The electron-electron interaction is usually supposed to be well described by the instantaneous Coulomb interaction operator l/rn. Also, all interactions with the nuclei whose internal structure is not resolved, like electron-nucleus attraction and nucleus-nucleus repulsion, are supposed to be of this type. Of course, corrections to these approximations become important in certain cases where a high accuracy is sought, especially in computing the term values and transition probabilities of atomic spectroscopy. For example, the Breit correction to the electron-electron Coulomb interaction should not be neglected in fine-structure calculations and in the case of highly charged ions. However, in general, and particularly for standard chemical purposes, these corrections become less important. 

Elemental mass spectrometry using an argon ICP as the ionization source (ICP-MS) is now also widely used for ultratrace determination of elements and is discussed in Chapters 9 and 10. Although ICP-MS complements atomic spectroscopy, it is not a spectroscopic method mass/charge ratio is determined, not radiant energy. 

It is not surprising that most results in atomic spectroscopy were obtained on singly charged ions which are difficult to prepare for the usual Doppler-free techniques on thermal samples. On the other hand, the fast-beam technique has certain advantages also on neutral atoms, such as the availability of metastable beams, the sensitivity, and the Doppler-tuning. 

Typically, a mixture of alkene (10 mmol), a 37.5 wt% solution of TBHP in toluene (14 mmol) and 500 mg of catalyst was magnetically stirred at 90 °C for 24 h. The catalyst was separated by filtration (PTFE filters pore width 0.45 pm) and employed in the next run without reconditioning. The filtrate was analyzed by GC and atomic spectroscopy. Epoxidation of propylene was carried out in a 80-ml steel autoclave charged with 50 mmol TBHP (34.0 wt% in toluene) and 1 g of catalyst. The solution was saturated with propylene and a pressure of 8 bar was adjusted. The reaction mixture was stirred for 24 h at 90 °C (operating pressure ca. 20 bar). Propylene oxide yields were based on peroxide consumption determined by iodometric titration and GC analyses. 

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