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Difference group

Analysis First convert the 1,6-dioxygenated compound to a 1,6-dicarbonyl compound, keeping the two carbonyl groups different ... [Pg.61]

Chemical Types. A wide range of reactive groups have been investigated, with 20—30 used commercially and over 200 patented. These have been described in detail elsewhere (10,20). Because these reactive groups differ chemically the activation of the reactive systems is different as are the rates of reaction with cellulose, from one reactive system to another. This rate of reaction with cellulose, or reactivity, dictates the temperature and pH needed for dyeing. [Pg.356]

Another possibility is observed upon cyclization of hydrazides of pyrazole-carboxylic acids in the presence of CuCl in an inert atmosphere in DMF. When acetylenylcarboxylic acids are heated in the presence of CuCl in DMF, the orientation of the cycloaddition of the hydrazide group differs from that observed for cyclization in basic conditions. The cycloisomerization of hydrazides 78 in boiling DMF leads to the corresponding pyrazolopyridazines 79 in 60-71 % yields (Scheme 134 Table XXIX) (85IZV1367 85MI2). [Pg.64]

Other periodic tables label the groups differently. but the elements have the same position. [Pg.32]

The solutes were benzene, ethyl benzene, butyl benzene, hexyl benzene, octyl benzene and decyl benzene and it is seen that the silica could easily resolve any two solute pairs having a difference of only two methylene groups. In fact, solutes having only one methylene group difference would have been discerned as two peaks. The disadvantage of the system can be seen from the time scale. The separation took over 10 hours to complete and this extensive time period was necessary even when using the maximum inlet pressure available of 6,000 p.s.i. [Pg.37]

An alternative technique to NMR spectroscopy is chromatography. The partially functionalized sample is completely fimctionahzed with a group different from the one present, the product carefully de-polymerized, its structure examined with a chromatographic technique. For example, partially substituted CA was further derivatized with methyl vinyl ether, the product hydrolyzed, the monomers produced examined with gas chromatography [241]. HPLC has been advantageously applied for the determination of substitution pattern for CAs with DS 0.8 to 3.0, by employing the same approach, i.e., further derivatization of the partially derivatized polymer with methyl trifluoroacetate, followed by de-polymerization. The results obtained by this technique compared favorably with those obtained by NMR [242]. [Pg.140]

Volume I includes the spectroscopic methods for nano interfaces and nanostructure characteristics and dynamics. Volume 2 groups different topics together in 3 parts active surfaces, single crystals and single biocells. [Pg.315]

Semiconductor adsorbents used as operational elements in sensors can be monocrystals or monocrystal films as well as polycrystals. The latter can be arbitrary divided into two groups differing in properties of contacts between monocrystals. The first group contains those polycrystal line adsorbents in which contacts between crystals can be represented as a double Shottky barrier or, in more general case, isotype hetero-... [Pg.107]

A pooled analysis of 14 875 adults (Hispanic, n = 361 White, n = 10 108 African American, n = 547 Asian, n = 112) who participated in 104 double-blind, placebo-controlled paroxetine trials for mood and anxiety disorders was performed to ascertain minority group differences (Roy-Byrne et al., 2005). There were significant differences in rates of response by ethnicity (p = 0.014) with the odds of responding being lower for the Asian and Hispanic subjects compared to the African American and White subjects. There was also a higher placebo response rate in Hispanic subjects. Rapidity of response and emergence of adverse effects were similar across groups. [Pg.99]

From the comparison of the results, it can be inferred that copper ions exchanged in the ZSM-5 zeolites assumes a bidentate (sites 12 and II) or tridentate coordination (sites M5, Z6, and M7). These two groups differ also in the molecular properties (Table 2.2). The I-centers are characterized by lower values of the valence index and greater partial charges, QCu, in comparison to the M and Z centers, which is associated with the deeper laying HOMO and LUMO levels. In the M5, Z6, and M7 sites Cu1 ions exhibit more covalent character, and the frontier orbitals have less negative energies. As a result, the chemical hardness of the I-centers, located at the channel intersections, is smaller than those located on the walls of the ZSM-5 zeolite. [Pg.32]

All the elements of Group IV have four electrons in the outer shells of their atoms. However, the elements in this group differ... [Pg.64]


See other pages where Difference group is mentioned: [Pg.157]    [Pg.192]    [Pg.140]    [Pg.489]    [Pg.493]    [Pg.361]    [Pg.374]    [Pg.38]    [Pg.168]    [Pg.204]    [Pg.131]    [Pg.328]    [Pg.345]    [Pg.306]    [Pg.81]    [Pg.78]    [Pg.122]    [Pg.43]    [Pg.177]    [Pg.170]    [Pg.341]    [Pg.58]    [Pg.113]    [Pg.171]    [Pg.204]    [Pg.208]    [Pg.175]    [Pg.312]    [Pg.283]    [Pg.59]    [Pg.69]    [Pg.114]    [Pg.348]    [Pg.87]    [Pg.4]    [Pg.22]    [Pg.218]    [Pg.586]    [Pg.437]    [Pg.96]   
See also in sourсe #XX -- [ Pg.252 ]




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