Trapping site

The ultimate trapping site for a photoelectron is influenced by the high dielectric constant of silver haUde (ca 12.5, 11.15, and 7.15 for AgBr, AgCl, and P-AgI, respectively), the negative surface charge, and relative trap depths. Interior traps located at point defects on dislocation lines are probably not as... 

There are many ways in which trapping can be studied, but the wide range of trap types and geometries make it difficult to determine the properties of specific trap sites. 

On a more positive note, it seems clear that steels can be made more resistant to the effects of hydrogen by incorporating as many strong, finely dispersed traps in the microstructure as is possible, while ensuring that there are no continuous trap sites (such as embrittled grain boundaries). 

Fig. 15. The optical spectrum of Cu Ar = 1 10 at 10-12 K, (A) showing isolated Cu atoms and Cuj molecules (B), (C) photoaggregation as the result of two 30-min irradiations in the resonance lines of Cu atoms at 302 nm, (D) photodissociation of Cu, resulting from a 30-min irradiation at the 370-nm band of Cu,. The features marked "a are thought to arise from secondary trapping sites of Cu,. Note the scale change between 325 and 400 nm (150).

As shown in Fig. 21.12, after X-ray irradiation, the BaBPOs crystal shows a few broad, distinct absorption bands from near-infrared to the band gap in the VUV, which indicates the presence of some trapping sites in the crystal and... 

The next best in the rank solely based on the HjS release onset temperature is CeOj. Notice in Figure 2, however, that there is practically no take-off in HjS release over Sample E as long as the temperature remains at 530 C. This represents a situation where SOj tiapp on the surface or stored in the bulk [10] is released very slowly, thus creating a condition where the rate of SO emission control is limited by the number of SOj trapping sites. 

Two types of species have been detected in the /rSR spectrum of Ceo- One shows an unreacted or meta-stable muonium state which may well correspond to an internal state, muonium is trapped inside the cage Mu Ceo in the current notation [2]. This may be compared with normal muonium (Mu ) in diamond and many other elemental and compound semi-conductors, where the trapping site is in one of the cavities of tetrahedral symmetry. This state of CeoMu is not discussed here, but it does exhibit all the characteristics expected of the internal chemistry of Ceo-The anomalous muonium state. Mu, observed in semi-conductors and generally accepted to arise from muonium being trapped within one of the chemical bonds of the crystal, is unknown in molecules [5,6]. The constraints of the crystal lattice are necessary for the bond-centred state to be stable. 

Benzyl alcohol. We have demonstrated that all benzyl aleohol (BzOH) moleeules dissolved in water are also immediately transported and trapped in the lipid bilayer phase, when it is mixed with EPC bilayer [46]. The trapped site of BzOH, however, differs from that of PrBe. As shown in Fig. 8, the ring proton signal of BzOH in water is at first broadened and shifted to a higher field [from (a) to (b)j then the signal is split into two (e). 

C NMR. The membrane perturbation by PRC H+ is found to be relatively smaller than DBC H. The ring current effect on the EPC h NMR signal is not substantial at any site. Only significant NMR downfield shift is noticed in the carbonyl site, as shown in Fig. 10. The difference in the perturbation effect between DBC H and PRC H supports the difference in the trapped site in bilayers and that in the anesthetic mechanism between the two drugs. 

Schnitker et al. s (1986) finding, based on classical molecular dynamics simulation, of a large density (4.4 ml-1 at 10°C) of local potential minima qualifying as trapping sites. 

The mere exposure of diphenyl-polyenes (DPP) to medium pore acidic ZSM-5 was found to induce spontaneous ionization with radical cation formation and subsequent charge transfer to stabilize electron-hole pair. Diffuse reflectance UV-visible absorption and EPR spectroscopies provide evidence of the sorption process and point out charge separation with ultra stable electron hole pair formation. The tight fit between DPP and zeolite pore size combined with efficient polarizing effect of proton and aluminium electron trapping sites appear to be the most important factors responsible for the stabilization of charge separated state that hinder efficiently the charge recombination. 

It is proposed that the B-state of Cu2 (bound in the gas phase) (57) is sufficiently strongly destabilized in the matrix to the extent that it is unstable with respect to dissociation to Cu(2D3/2) + Cu(2S1/2) fragments following photoexcitation of CU2 from the ground state, process (1) in above scheme. The extent to which the dissociation actually occurs depends on the local dynamics following photoexcitation and the details of the Cu2 rare gas potentials for the specific trapping site involved. 

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