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Translational variation

This is largely because the two techniques share the same key elements - a passivated tip (H-passivated in the case of Termirov et al. s results) and operation within the Pauli repulsion regime - although the contrast mechanisms are of course rather different. For STHM, the passivated tip translates variations in tip-sample force into a modulation of the junction conductance. As can be seen from Fig. 10(b) the image resolution far exceeds that observed in conventional STM because the latter is sensitive only to variations in electron density in a relatively narrow energy window close to the Fermi level. In STHM, as pointed out by Temirov et it is variations in the total electron density - and the information on chemical structure embedded within it which are probed. [Pg.130]

Although a diatomic molecule can produce only one vibration, this number increases with the number of atoms making up the molecule. For a molecule of N atoms, 3N-6 vibrations are possible. That corresponds to 3N degrees of freedom from which are subtracted 3 translational movements and 3 rotational movements for the overall molecule for which the energy is not quantified and corresponds to thermal energy. In reality, this number is most often reduced because of symmetry. Additionally, for a vibration to be active in the infrared, it must be accompanied by a variation in the molecule s dipole moment. [Pg.57]

Variational RRKM theory is particularly important for imimolecular dissociation reactions, in which vibrational modes of the reactant molecule become translations and rotations in the products [22]. For CH —> CHg+H dissociation there are tlnee vibrational modes of this type, i.e. the C—H stretch which is the reaction coordinate and the two degenerate H—CH bends, which first transfomi from high-frequency to low-frequency vibrations and then hindered rotors as the H—C bond ruptures. These latter two degrees of freedom are called transitional modes [24,25]. C2Hg 2CH3 dissociation has five transitional modes, i.e. two pairs of degenerate CH rocking/rotational motions and the CH torsion. [Pg.1016]

Intermolecular DD 2 Distance variation by translational diffusion Less common [12]... [Pg.1506]

The more effective deflvery of natural gas is being realized by the use of computerized operation centers that allow rapid responses to the variations ia gas demand. Automated valves, more precise measuting systems, and high speed communication networks make it possible to closely monitor and manage the transmission and deflvery of natural gas. This translates iato improved service and cost effectiveness. [Pg.176]

Insect Cells. In this system the cDNA is inserted into the genome of an insect vims, baculovims. Insect cells, or Hve insect larvae, are then infected with the vims. In this way advantage is taken of the vims s natural machinery for repHcation utilizing the insect cell. This is one of the best systems available for high level production of native protein having post-translational modifications similar to those seen in mammalian cells. Disadvantages of this system include lytic—batch variations, comparatively slow growth, and cosdy scale-up. [Pg.200]

It is an extremely difficult task to establish generally valid sufficient conditions for roughness-induced wetting. This is a direct consequnce of the loss of translational invariance in such systems. A vast majority of the hitherto performed calculations [185,201] have been based on a simplified model of a rough substrate which assumes periodic variation of the substrate surface location. [Pg.286]

Recognition among bone-chemistry researchers that strontium enters bone in proportion to dietary levels has resulted in widely accepted yet erroneous inferences about the relationships among various elements in bone and past diet. One such inference is that more of any element in the diet translates directly to more of that element in bone. If an element is not biogenically incorporated within bone, or if biological levels are metabolically controlled, then that element will not reflect diet. A second erroneous inference is that strontium can be used to measure the dietary plant/meat ratio. Sr/Ca ratios in meat are generally lower than those of plants, but meat is also low in calcium and hence has little effect on the composition of bone. Plants, on the other hand, contribute substantially to bone composition. Variations in the strontium levels of bone thus more likely reflect differential consumption of plants rather than trophic position. Although efforts to determine plant/meat ratios from strontium and to draw dietary inferences from elements other than strontium and barium have not been successful, this failure has been due to inappropriate expectations, not to a failure of bone strontium to reflect diet. [Pg.159]

Synthesis of the transferrin receptor (TfR) and that of ferritin are reciprocally linked to cellular iron content. Specific untranslated sequences of the mRNAs for both proteins (named iron response elements) interact with a cytosolic protein sensitive to variations in levels of cellular iron (iron-responsive element-binding protein). When iron levels are high, cells use stored ferritin mRNA to synthesize ferritin, and the TfR mRNA is degraded. In contrast, when iron levels are low, the TfR mRNA is stabilized and increased synthesis of receptors occurs, while ferritin mRNA is apparently stored in an inactive form. This is an important example of control of expression of proteins at the translational level. [Pg.586]

We found a slight decrease of pH during reaction (0.1-0.2 pH units in the buffer zone of ethanolamine), which however translated as a decrease of about 20% of the concentration of OH ions. Above pH 10.5, the loss in OH ions reached about 40% of the initial concentration. This variation could be predicted by taking into account the need for replacement of the buffer ions at any time t 0 eletroneutrality implies that for every carboxylate liberated (i.e. every methoxylated galacturonate saponified), one molecule of ethanolamine is converted from the base form (EtNHj) to the salt form (EtNH, ). The concentration of the base and salt forms at... [Pg.605]


See other pages where Translational variation is mentioned: [Pg.29]    [Pg.239]    [Pg.176]    [Pg.29]    [Pg.239]    [Pg.176]    [Pg.661]    [Pg.873]    [Pg.2553]    [Pg.389]    [Pg.436]    [Pg.249]    [Pg.240]    [Pg.54]    [Pg.249]    [Pg.1827]    [Pg.291]    [Pg.121]    [Pg.71]    [Pg.113]    [Pg.94]    [Pg.401]    [Pg.97]    [Pg.27]    [Pg.118]    [Pg.387]    [Pg.109]    [Pg.17]    [Pg.389]    [Pg.354]    [Pg.68]    [Pg.219]    [Pg.265]    [Pg.40]    [Pg.30]    [Pg.90]    [Pg.114]    [Pg.220]    [Pg.33]    [Pg.882]    [Pg.161]    [Pg.233]   
See also in sourсe #XX -- [ Pg.29 , Pg.30 ]




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