Blue cluster

We can draw a very simplified picture of a z 0 cluster in the optical (e.g. Sarazin 1986). If a cluster is virialized, on the one hand bright and/or red cluster galaxies (mainly early types) will have small velocity dispersions and will be central objects with circular orbits. On the other hand, faint and/or blue cluster galaxies (mainly late types) will be external objects with radial orbits in the cluster. This is verified for nearby clusters (e.g. ENACS survey Adami et al. 1998a)(Fig. 6). 

Figure 3. Partial density of states projected on the d-hond of Pts for bare [Xbuik- sJ-Pts (red) and oxygen-chemisorbed [Xbuik- s]-Pt3-02 (blue) clusters. The samples of surface atoms Xs considered are (a) Co2Pt, (b) C03, (c) Pt3, (d) Ni3 and (e) Fe3. The d-hond of bulk Pt (shaded green) is shown as reference. In all panels, the vertical dashed line at zero-energy marks the Fermi level.

E plots the Raman band and CARS signal at 1000 cm" that are assigned predominantly to proteins. A wider gap is similarly resolved here. Cluster analysis of the Raman image identifies three main groups of spectra that are displayed in Figure 3.5. The spectrum of the tissue (blue cluster) contains spectral contributions of proteins and nucleic acids, whereas lipid bands are weak. The intensities of lipid bands increase and the intensities of proteins and nucleic acids decrease in the spectra of the gaps. It can be concluded that the gap is filled with lipids of different density. The result of the underlying chemical composition can only be obtained by multivariate analysis of hyperspectral Raman data such as k-means cluster analysis. Similar observations were also made for brain tissue as described in the later section. 

Tungsten pentachlofide [13470-13-8], WCl, mp 243°C, bp 275.6°C, is a black, crystalline, deHquescent soHd. It is only slightly soluble in carbon disulfide and decomposes in water to the blue oxide, 200 2. Magnetic properties suggest that tungsten pentachlofide may contain trinuclear clusters in the soHd state, but this stmcture has not been defined. Tungsten pentachlofide may be prepared by the reduction of the hexachloride with red phosphoms (9). 

An intriguing class of persistent radicals are those formed by the one-electron oxidation of the hexagonal prismatic clusters Li2[E(N Bu)3] 2 (3.21, E = S, Se). The air oxidation of 3.21 produces deep blue (E = S) or green (E = Se) solutions in toluene. The EPR spectra of these solutions consist of a septet (1 3 6 7 6 3 1) of decets (Eig. 3.5). This pattern results from interaction of the unpaired electron with three equivalent 7=1 nuclei, i.e., and three equivalent I = 3/2 nuclei, i.e., Ei. It has been proposed that the one-electron oxidation of 3.21 is accompanied by the removal of an Ei" cation from the cluster to give the neutral radical 3.22 in which the dianion [S(N Bu)3] and the radical monoanion [S(N Bu)3] are bridged by three Ei" cations. 

Time-resolved luminescence quenching measurements using the probe Tb(pyridine-2,6-dicarboxylic acid)i and the quencher bromophenol blue show the existence of micellar clusters in AOT-based w/o microemulsions. The fast exchange appearing over several microseconds was attributed to intracluster quenching, whereas the slow exchange on the millisecond time scale was attributed to intercluster exchange [243]. 

Liu, Z., Peng, L.and Yao, K. (2006) Intense blue luminescence from self-assembled Au-thiolate clusters. Materials Letters,... 

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