Cluster difference

I. Dauster, M. A. Suhm, U. Buck, and T. Zeuch, Experimental and theoretical study of the microsolvation of sodium atoms in methanol clusters Differences and similarities to sodium water and sodium ammonia. Phys. Chem. Chem. Phys. 10, 83 95 (2008). 

The octahedral metal clusters that have long been familiar features of the lower halide chemistry of niobium, tantalum, molybdenum, and tungsten represent a category of cluster different from those so far considered in that their metal-metal bonding is best treated as involving four AO s on each metal 49, 133,144,165,178). 

The two clusters differ in their metal-binding properties. Mammalian Cd, Zn metallothionein contains four Cd ions in cluster A and two Cd ions and one Zn ion in cluster B. 1157,1159 Calf liver metallothionein contains three Cu ions in cluster B with Cd-displaceable zinc ions in cluster A.1160 Studies on the binding of zinc and cadmium to human liver metallothionein show that binding occurs first in cooperative fashion to cluster A, followed by cooperative binding to cluster B. Incubation of the 7Cd metallothionein resulted in loss of Cd ions from cluster B initially.1161... 

The fragmentation of 2-acylpyrroles (6) and 3-pyridinols (7) on electron impact (El) has been elucidated and is shown for L -7 in Figure 7. The two numbers under each ion are the m/z values expected with the label at the alternative positions, the latter number within parantheses corresponding to labelled methyl carbon. Where the two m/z values differed, the peak at the first one always predominated in the El mass spectra of the labelled (J-7 obtained on GC/MS analysis of Extracts 1 and 3. This was in complete accordance with the 1 5C-NMR spectrometric results, but for several reasons the mass spectrometric results were less accurate and did not exclude up to 15 % of the label in the respective methyl groups. Most important, the spectra showed clusters of peaks at consecutive m/z values, including those of interest. The content was calculated by means of a computer program based on the somewhat doubtful assumption that ions in the same cluster differed only in hydrogen content and/or isotopic composition. 

JJR Coque, JF Martin, P Liras. Characterization and expression in Streptomyces lividans of cefD and cefE genes from Nocardia lactamdurans the organization of the cephamycin gene cluster differs from that in Streptomyces clavuligerus. Mol Gen Genet 236 453-458, 1993. 

However, the most discriminatory metagenomic clusters differed between cohorts, emphasizing the need for development of population-specific metagenomic predictive methods. 

With the exception of the findings at very low temperatures, the global minimum of the benzene...Ar (n = 2, 3, 5, 7, 8) clusters was not most populated. The low populations of the global minima having one-sided structures and high populations of two-sided and bridged structures are explained by the entropy term. The PES and FES of titled clusters differ... 

Corymb, a short, broad cluster, differing from the raceme mainly in its shorter axis and longer lower pedicels, which give the cluster a flat appearance by bringing the individual florets to nearly the same level. Example Cherry. 

Due to the weak scattering by H atoms, diffraction patterns from CH4 clusters are strikingly similar to Ar ones. On the other hand patterns from N2 clusters differ considerably since there is no scattering atom at the molecule center. Size effects are particularly appreciable in N2 clusters and can be... 

The focus of this review will be on the effects resulting from the existence of a third body, or several solvent sjjecies, and how the reaction of a cluster differs from the reaction of two isolated molecules. Having vdW molecules as partners in reactions, several effects can be introduced, which are not present in the case where two isolated molecules are involved. These phenomena can be classified as follows ... 

Chloroplast ferredoxin containing the [(2Fe-2S)-(S-Cys)4] cluster is one common type of iron-sulfur protein. Another [2Fe-2S]-type protein is the Rieske iron-sulfur protein, present in the Cyt >6/complex as well as the Cyt Ac, complex. The pair of iron atoms in the cluster ofthe Rieske iron-sulfur protein are bound to two cysteine and two histidine residues, in addition to two sulfur atoms. The three-dimensional structures of ferredoxins and that of the Rieske iron-sulfur protein have been determined by X-ray crystallography (see Chapters 34 and 35, respectively, for the structure ofthe chloroplast ferredoxin and the Rieske iron-sulfur protein). The sulfide ions in iron-sulfur proteins urt acid-labile this provides a simple means for detecting the iron-sulfur proteins, as the sulfide is released as H2S upon acidification. The oxidized and reduced states of iron-sulfur clusters differ by just one unit of formal charge, corresponding to and Fe. Iron-sulfurproteins are commonly characterized by optical absorption, circular-dichro-... 

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