Intermediate/homologous series

The intermediate/homologous series of mixed-valent oxides 422... 

The intermediate/homologous series of mixed-valent oxides As is evident from figs. 3-5, Ce, Pr and Tb form intermediate compounds of narrow composition ranges of which most, but not all, have compositions with the generic... 

Figure 10. The TEM micrograph of one part of a WS2 nanotube in an intermediate stage where tungsten suboxide is in the core. The core presents ordered 001 R CS planes along the tube axis. The stoichiometry of this sample phase belongs to the homologous series Wn03n j (W5014) (8b). [Courtesy of J. Sloan and J. L. Hutchison, Oxford University.]...

Achiral cycloalkyl quaternary amino acids have also been incorporated into model peptides using 5(47/)-oxazoIones as intermediates. A comparative study between cyclic and acyclic derivatives has been described. The influence of the ring size of a homologous series from l-aminocyclopropanecarboxylic acid to... 

Precipitation. When two surfactants of like charge are mixed together, and the structures are very similar (e.g., close members of an homologous series) and containing the same counterion, the Krafft temperature of the mixture is intermediate between the pure components or shows only a very shallow minimum (86.87) The crystals are mixed (contain both surfactants) in this case (86.87). 

An isolated cs plane or a random array of cs planes, known as the Wadsley defect, still gives rise to nonstoichiometry. Regularly recurring cs planes result in a homologous series of stoichiometric intermediate phases. Occurrence of such equidistant cs planes in a crystal indicates a cooperative mechanism. The formula of a cs phase depends on the cs plane index as well as the width of the parent slab between cs planes. If MO is the formula of the parent line phase, the formula of the homologous series of oxides resulting from cs may be represented as where n is the width (number of... 

The lower members of the homologous series of 1. Alcohols 2. Aldehydes 3. Ketones 4. Acids 5. Esters 6. Phenols 7. Anhydrides 8. Amines 9. Nitriles 10. Polyhydroxy phenols 1. Polybasic acids and hydro-oxy acids. 2. Glycols, poly-hydric alcohols, polyhydroxy aldehydes and ketones (sugars) 3. Some amides, ammo acids, di-and polyamino compounds, amino alcohols 4. Sulphonic acids 5. Sulphinic acids 6. Salts 1. Acids 2. Phenols 3. Imides 4. Some primary and secondary nitro compounds oximes 5. Mercaptans and thiophenols 6. Sulphonic acids, sulphinic acids, sulphuric acids, and sul-phonamides 7. Some diketones and (3-keto esters 1. Primary amines 2. Secondary aliphatic and aryl-alkyl amines 3. Aliphatic and some aryl-alkyl tertiary amines 4. Hydrazines 1. Unsaturated hydrocarbons 2. Some poly-alkylated aromatic hydrocarbons 3. Alcohols 4. Aldehydes 5. Ketones 6. Esters 7. Anhydrides 8. Ethers and acetals 9. Lactones 10. Acyl halides 1. Saturated aliphatic hydrocarbons Cyclic paraffin hydrocarbons 3. Aromatic hydrocarbons 4. Halogen derivatives of 1, 2 and 3 5. Diaryl ethers 1. Nitro compounds (tertiary) 2. Amides and derivatives of aldehydes and ketones 3. Nitriles 4. Negatively substituted amines 5. Nitroso, azo, hy-drazo, and other intermediate reduction products of nitro com-pounds 6. Sulphones, sul-phonamides of secondary amines, sulphides, sulphates and other Sulphur compounds... 

Of the 15 experimentally known phases of the higher oxides only five of them have been determined by X-ray and neutron diffraction using the Rietveld refinements method. To understand the thermodynamic behavior and phase reactions it is helpful to have a model of the undetermined structures. Using the experimental electron diffraction data it is possible to determine the symmetry of the unit cell and develops a transformation matrix between the fluorite and ten of the intermediate phases as shown in Table 2. The module theory provides a method for modeling the unknown structures of the homologous series of the lanthanide... 

Mixtures that are fuel-rich or fuel-lean ignite at higher temperatures than do those of intermediate compositions. Also, in a homologous series of organic compounds, the AIT decreases with increasing molecular weight, as shown in Fig. 3.4. 

Stable phases in the rare earth oxide systems are tabulated and discussed. New data on the structure of sesquioxides quenched from the melt are reported. The structural interrelations between the A, B, and C type sesquioxides and the fiuorite dioxides are pointed out. The sequences of several intermediate oxides in the CeO, PrO., and TbO, systems are observed to be related to the fluorite structure and the C form sesquioxide with respect to the metal atom positions. A hypothetical homologous series of the general formula Mn02n i, related to the fluorite structure and the A form sesquioxide with a more or less fixed oxygen lattice, is suggested. 

On the basis of the heterogeneous mechanism of foam inhibition Kruglyakov and Koretskaya [56,91] have given an explanation of the reasons for inversion of the defoaming ability within a homologous series of alkyl alcohols with the increase in surfactant concentration and the maximum effectiveness of the intermediate members of the series at intermediate surfactant concentrations. 

The five well-characterized molecular ones form a structurally homologous series. The structures of the end members, P406 and P4O10, are shown in Fig. 10-10. The intermediate ones have 1, 2, or 3 exo oxygen atoms added to the P406 structure. Preparative methods for the intermediate members are varied and not simple and will not be given here. 

Alberty, R. A., Use of an ensemble intermediate between the generalized ensemble and the isothermal-isobaric ensemble to calculate the equilibrium distribution of hydrocarbons in homologous series, J. Chem. Phys. 84,2890 (1986). 

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