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Generational differences

In some cases, particularly with iaactive metals, electrolytic cells are the primary method of manufacture of the fluoroborate solution. The manufacture of Sn, Pb, Cu, and Ni fluoroborates by electrolytic dissolution (87,88) is patented. A typical cell for continous production consists of a polyethylene-lined tank with tin anodes at the bottom and a mercury pool (ia a porous basket) cathode near the top (88). Pluoroboric acid is added to the cell and electrolysis is begun. As tin fluoroborate is generated, differences ia specific gravity cause the product to layer at the bottom of the cell. When the desired concentration is reached ia this layer, the heavy solution is drawn from the bottom and fresh HBP is added to the top of the cell continuously. The direct reaction of tin with HBP is slow but can be accelerated by passiag air or oxygen through the solution (89). The stannic fluoroborate is reduced by reaction with mossy tin under an iaert atmosphere. In earlier procedures, HBP reacted with hydrated stannous oxide. [Pg.168]

If uneontrolled, temperature ean have a signifieant effeet on reprodueibility and the robustness of separations. This ean eause major problems in metlrod transferability between laboratories and at its worst ean require a method to be reoptimised or revalidated. Most separations therefore require a tlrermostated environment. However, the important faetor is tire temperature witlrin the eolumn bed, not just the sunounding enelosure. Cireulating ah ovens, statie air ovens, metal bloek heaters and eireulating water baths ean all generate different effeetive temperatures even if set to the same nominal values. [Pg.16]

Cellular therapies in transplantation and cancer are based on specific cells separated or sorted from human blood, bone marrow, or cord blood by means of their specific cell surface markers or cell differentiation antigens, e.g., CD3, CD4, CD8, CD 14, CD 19, and CD34. For example, the CD34+ stem cells, especially those derived from human embryos, have the capacity to differentiate in culture to generate different somatic cells, e.g., liver cells, heart cells, neurons, etc. This exploding field of research is now termed regenerative medicine. [Pg.265]

The p-n junction collapses the 3-D charge distribution into a 2-D array. The pixel boundaries of the 2-D arrays are generated differently in optical and infrared detector arrays. [Pg.145]

This effect is particularly well documented for y - and -amino acid residues [217, 218] which in several natural products (bleomycin A2 [219], calyculins [220]) have been shown to play a substantial role in the pre-organization of the whole molecule into its bioactive conformation. For example, changes in the substitution pattern of the y-amino acid linker in bleomycin A2 result in reduced DNA cleavage efficiency [219]. In the case of y-peptides, changing the relative configuration like or unlike of y " -amino acids has been used as a strategy to generate different local conformations (Fig. 2.34) suitable either for the construction of helices [201] or turns ]202-204]. [Pg.83]

The magnetic quantum number derives its name from the fact that different orbital orientations generate different behaviors in... [Pg.472]

They correspond to the cross-metathesis of propylene with the neopentyli-dene fragment (Scheme 18), and their relative ratio corresponds to a photograph of the active site as they are formed. Depending on how propylene will approach the carbene, it will generate different metallacyclobutanes, whose stabilities can direct the relative amounts of cross-metathesis (and selfmetathesis) products. This model is based on the following the favoured cross-metathesis product arises from the reaction pathway, in which [1,2]-interactions are avoided and [1,3]-interactions are minimized (here shown with both substituents in equatorial positions) [83]. [Pg.174]

Structural changes of the temporal superstructure can generate different operating modes (batch or semibatch). The reactants that are fed at the beginning of a batch are treated as feed streams at the start of the network, while the intermediate batch feeds, semicontinuous feeds and product takeoffs are represented as sidestreams feeding to, or withdrawing from, the network at different time intervals3. [Pg.293]

Polarisation modulation infrared rejiection-absorption spectroscopy (PM-IRRAS or JRRAS). Potential modulation IR studies rely on switching the potential at a reflective electrode between rest and active states, generating difference spectra. However, the EMIRS technique has several drawbacks the relatively fast potential modulation requires that only fast and reversible electrochemical process are investigated the absorption due to irreversibly chemisorbed species would be gradually eliminated by the rapid perturbation. Secondly, there is some concern that rapid modulation between two potentials may, to some extent, in itself induce reactions to occur. [Pg.107]

For a given unit cell size (supercell) generate different individual arrangements (configurations) k. For the alloy A0.5B0.5 these will comprise all arrangements with 50% of the atoms of type A and 50% type B. [Pg.353]

Photochemical reactions occur when a gas, a solution, or a solid mixture of chemicals absorbs light to produce an excited state, which further reacts generating different reaction products. Part of the excited-state particles might not convert into new species, but rather revert to the ground-state species. The research field of heterogeneous photochemistry is focused toward the investigation of each of the above-mentioned steps and elucidation of their mechanism and kinetics. [Pg.428]

We shall use roulette wheel selection. Spinning the virtual wheel ten times gives us ten strings as the starting point for the new population (Table 2). We note that the fitter strings are indeed now more numerous than before, as we would expect, although, as there is a stochastic element in the choice of parents, repeated runs on the same problem can be expected to generate different results. [Pg.355]

Sills, M.A., Weiss, D., Pham, Q., Schweitzer, R., Wu, X., and Wu, J.J., Comparison of assay technologies for a tyrosine kinase assay generates different results in high throughput screening, /. Biomol. Screen., 7,191, 2002. [Pg.98]


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Comparison of Random Packings from Different Generations

Difference generation

Difference generation

Difference-frequency generation infrared pulses

Electric difference generation

Electrochemical cell electric potential difference generated

Frequency generation difference

Generated by Different Parts of the Chromatographic System

Reaction conversions, different generations

Second-harmonic generation linear difference

Second-harmonic generation linear difference nonlinear optics

Sum and Difference Frequency Generation

Training generational differences

Unit differences, generating

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