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Small clusters

Similarly, as for the production of other passito wines from partially dried grapes, such as Recioto, Albana passito, and Picolit (which we refer to as "non-aromatic passito wines"), generally the grape varieties and clones used should be those with a thicker skin and more open clustered small berries, as these are best for drying under mild conditions, with less... [Pg.74]

Based on Daylight s Fingerprint and Tanimoto Similarity a Fast and Automated Way to Cluster Small and Large Data Sets. [Pg.40]

FIGURE 11. An escapement mechanism is sometimes used to control the direction of electron transfer within a redox cluster (small box). Here electron transfers from the substrate (close pair of circles filled with electrons) to a redox center on the left which is effectively insulated by distance from other members of a redox chain (further left) so only one electron can be transferred. The radical intermediate can transfer electrons to the chain on the right. The thermally activated escapement motion of the redox center then carries an electron to the chain at the left, and finally reassembles the cluster in preparation for the next catalysis. [Pg.22]

This is due to the strong (j-bonding of Au -CO [57] which provides a large amount of energy allowing any subsequent barriers to the oxidation of CO to be easily overcome because all of the energy is retained in the gas-phase cluster. Small positive gold centers, therefore, may be the most active sites for CO oxidation. [Pg.302]

The presence of an ion is more disruptive the smaller the cluster, especially when the majority of molecules occupy surface sites. In the larger clusters, small changes in the local environment of many molecules facilitate both the migration and the accommodation of the ion. [Pg.512]

This occurs when stable clusters small, form on the substrate surface and grow in three dimensions to form separate islands. This happens when the bonding between atoms in the clusters is much greater and stronger than that between the atom and the substrate. Many systems of metals on the insulators of micro-electronic devices display this mode of growth, such as silicon growth an Si02 substrate reported by Bloem [8],... [Pg.217]

Cluster small or colloid compositions of transition metal oxides or metal hydroxides. [Pg.313]

Special processes of diffusion transfer in silver photographic emulsions require diffusion of silver ions of the positive image and their catalytic reduction around added development centers such as metal clusters, small enough to ensure a high resolution and no loss of transparency. Added y-induced silver clusters have a strong efficiency. However, alloyed clusters of Au-Cu and Ni-Pt and mostly of Ag-Au, Ag-Cu, and Ag-Cu-Pd, prepared under... [Pg.441]

Colorless, partly clustered small rods, pointed at the ends. When stored for some time in a closed container (even at 0 °C) turns dark because of decomposition very sensitive to moisture and O3. After removal from the clay dish, the product is still contaminated with 0.1-0.2 moles of NaOH per mole. During separation and drying, a small percentage of the Sn (II) Is converted to Sn (IV). [Pg.1688]

Alite cluster, small crystals (10 pm) plus minor f-CaO or belite In same cluster Marly grain near cement composition (Fundal, 1980)... [Pg.74]

A more detailed interpretation of this absorption was performed by Zecchina et al. [52]. The authors depicted two different situations, which depend on the equivalence or non-equivalence of the force constants of the Si-0 and Ti-0 bonds. In the first case, the replacement of Ti for Si induces a shift of the B mode of vibration of the [TO4] units from 1120 (T=Si) to 960 cm (T=Ti), the shift being simply due to mass effects. In the second case a higher polarity is considered for the Ti-0 bond, leading to the conclusion that the 960 cm" absorption is due to the local mode of a [Si04] unit (large difference in polarity between the two bonds) or to the stretching modes of the [Ti(0Si03)4] cluster (small difference in the bond polarity) [52]. [Pg.198]

In subepithelial soft tissue and bone specimens from 19 patients in whom implants (14 stainless steel and 5 titanium) had been in situ for more than 6 months, there were scattered T lymphocyte clusters, small numbers of macrophages, and abundant expression of HLA-DR in the soft tissue adjacent to both types of implant [7T]. There were immunocompetent cells in the connective tissue lining the periphery of the screw holes and metal particles in the soft tissues and bone. [Pg.456]

In the synthesis of high nuclearity carbonyl clusters, small clusters are often used as starting materials ... [Pg.125]

The case C in Fig. 19.19 depicts the droplet pattern for the polydisperse spray. The structures described before are coexisting in the polydisperse spray. Larger droplets (ifdropiet > 50 pm) can be found on the spray axis without the tendency to form clusters. Small droplets (tfdropiet <10 pm) can be found equally distributed in the spray, also inside of vortices (tracer-like behavior). The 10 pm droplets show a distinctive cluster pattern in the flow (case A). Their mean and fluctuating velocity values of the dispersed and the continuous phase are correlated. Here, the velocity slip between the continuous and the dispersed phase is not negligible. [Pg.781]

The method (described in [1, 2]) yields large clusters (small particles) by vaporization and condensation of a metal in a rare-gas atmosphere at pressures between a few tenth and a few ten Torr. Clusters (particles)... [Pg.325]

Because they have low vapor pressures, transition metals cannot be loaded by direct adsorption, but their adsorption can be mediated by transient organo-metallic complexes formed between zerovalent metal atoms and solvent molecules. This is the basis of the solvated metal atom dispersion (SMAD) method developed by Klabunde and Tanaka [72]. Metal vapors condensed in Hquid hydrocarbons at low temperatures form weak complexes that are easily decomposed even below room temperature. Microporous supports impregnated with solutions of metal complexes at low temperatures are warmed up to decompose the complex and liberate zerovalent metal atoms which nucleate into clusters. Preparation of Ni- and Co-clusters in HY and HZSM-5 was reported [72]. In the same way, Nazar et al. [64] condensed iron and cobalt vapors in a slurry of dehydrated NaY zeolite in toluene at -120 °C, then the mixture was rotated at-78°C. The bis-toluene complex thus formed and adsorbed in the zeoUte was decomposed by warming to room temperature yielding clusters small enough to fit into supercages. [Pg.265]

So the term BM was introduced and called metabolic body mass (MBM), which is, in fact, proportional to HL within a species or related species. Assuming a proportionality of HL and MBM the heat balance of the body requires a proportionality between EE and MBM too. This, however, introduces a differentiation of indirect calorimetric measurements by body mass. On first hand there is calorimetry on humans and large (farm) animals, often done in relatively large (and convenient) calorimetric chambers with volumes (V) of up to 25 m On the other hand there is indirect calorimetry on small (laboratory) animals, even organ tissue or cell clusters. Small animal calorimetry can perfectly be done in relative small cages with volumes of Just a few litres, whereas tissues or cell clusters can be investigated in small ampoules [25]. [Pg.523]


See other pages where Small clusters is mentioned: [Pg.177]    [Pg.7]    [Pg.280]    [Pg.172]    [Pg.25]    [Pg.218]    [Pg.50]    [Pg.442]    [Pg.105]    [Pg.139]    [Pg.11]    [Pg.189]    [Pg.138]    [Pg.342]    [Pg.110]    [Pg.342]    [Pg.488]    [Pg.208]    [Pg.87]    [Pg.360]    [Pg.71]    [Pg.166]    [Pg.738]    [Pg.299]    [Pg.302]    [Pg.285]    [Pg.555]   


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