Intermediate properties

The lower members in Group II form essentially ionic halides, with magnesium having intermediate properties, and both magnesium bromide and iodide dissolve in organic solvents. 

Structurally the difference between PEN and PET is in the double (naphthenic) ring of the former compared to the single (benzene) ring of the latter. This leads to a stiffer chain so that both and are higher for PEN than for PET (Tg is 124°C for PEN, 75°C for PET is 270-273°C for PEN and 256-265°C for PET). Although PEN crystallises at a slower rate than PET, crystallization is (as with PET) enhanced by biaxial orientation and the barrier properties are much superior to PET with up to a fivefold enhancement in some cases. (As with many crystalline polymers the maximum rate of crystallisation occurs at temperatures about midway between Tg and in the case of both PEN and PET). At the present time PEN is significantly more expensive than PET partly due to the economies of scale and partly due to the fact that the transesterification route used with PEN is inherently more expensive than the direct acid routes now used with PET. This has led to the availability of copolymers and of blends which have intermediate properties. 

The above qualitative conclusions made on the basis of the results of [116, 124-127] correlate with the results of [129,130] in which the calculation is based on composite models with nucleus-shell inclusions. The authors illustrate this with the calculation of a system consisting of a hard nucleus and elastomeric shell in a matrix of intermediate properties, and a system where the nucleus and matrix properties are identical whereas the shell is much more rigid. The method may, however, be also applied to systems with inclusions where the nucleus is enclosed in a multi layer shell. Another, rather unexpected, result follows from [129,130] for a fixed inclusions concentration, the relative modulus of the system decreases with increasing nucleus radius/inclusion radius ratio, that is with decreasing shell thickness. 

Molecular hybrids between organic polymers and silica gel are expected to show many possibilities as new composite materials. First, the hybrids may show intermediate properties between plastics and glasses (ceramics). In addition, the composition of the hybrids can be widely varied. In other words, the hybrids can be used to modify the organic polymer materials or to modify the inorganic glassy materials. The hydrophilic modification as described before is a typical example. 

Some wild species have larger capacities for osmotic adjustment, a trait which may improve yield during drought (Table 3, Turner, 1986). Interesting examples of this are Dubautia species from Hawaii which differ in osmotic adjustment mainly as a result of differences in cell wall elasticity. Interspecific hybrids can be made which have intermediate properties (Robichaux, Holsinger Morse, 1986). Material such as this could make a basis for the molecular study of differences in cell wall elasticity. 

When crystals with covalent bonds (e.g., AICI3 or TiCy melt, the melt conductivity remains low (e.g., below 0.1 S/m), which implies that the degree of dissociation of the covalent bonds after melting is low. The covalent crystals also differ from the ionic crystals by their much lower melting points. The differences between these two types of crystal are rather pronounced, whereas there are few crystalline solids with intermediate properties. 

Gas-expanded liquids (GXLs) are emerging solvents for environmentally benign reactive separation (Eckert et al., op. cit.). GXLs, obtained by mixing supercritical CO2 with normal liquids, show intermediate properties between normal liquids and SCFs both in solvation power and in transport properties and these properties are highly tunable by simple pressure variations. Applications include chemical reactions with improved transport, catalyst recycling, and product separation. 

Phosphofructokinase (PFK) is a key regulatory enzyme of glycolysis that catalyzes the conversion of fructose-6-phosphate to fructose-1,6-diphosphate. The active PFK enzyme is a homo- or heterotetrameric enzyme with a molecular weight of 340,000. Three types of subunits, muscle type (M), liver type (L), and fibroblast (F) or platelet (P) type, exist in human tissues. Human muscle and liver PFKs consist of homotetramers (M4 and L4), whereas red blood cell PFK consists of five tetramers (M4, M3L, M2L2, ML3, and L4). Each isoform is unique with respect to affinity for the substrate fructose-6-phosphate and ATP and modulation by effectors such as citrate, ATP, cAMP, and fructose-2,6-diphosphate. M-type PFK has greater affinity for fructose-6-phosphate than the other isozymes. AMP and fructose-2,6-diphosphate facilitate fructose-6-phosphate binding mainly of L-type PFK, whereas P-type PFK has intermediate properties. 

It will be clear from the above that the optimum types of oxidising materials are those of highest density and dense forms of ammonium nitrate are always used. The combustibles can be dense also, although it is sometimes necessary to add at least a proportion of the combustible in an absorbent form to ensure adequate sensitiveness. Wheat flour may be regarded as typical of a dense combustible woodmeal is a useful and cheap combustible of intermediate properties. 

Relative to specimens examined under the microscope, the a or fast axis corresponds to the direction of the minimum refractive index, the minimum dielectric constant, and the maximum velocity. The y or slow axis corresponds to the maximum refractive index, the maximum dielectric constant, and the minimum velocity. Occasionally, a (3 axis is recognized with intermediate properties between a and y. When working with elongated bireffingent structures, birefringence usually is taken as positive when the y axis is parallel to the longitudinal axis. 

PA 610 and PA 612 have intermediate properties between PA 66 and PA 11. Concerning sensitivity to water and moisture they are nearer to PA 11, and nearer to PA 66 for rigidity. 

Shape descriptor derived from the second derivative of the electronic energy distribution with 2 meaning the shorter length rays are represented and 4 meaning that intermediate property values are represented. 

Superficially, this seems to contradict the rule that the use of explosives which do not detonate but only explode (or burn) like blackpowder, as mentioned above, is unsafe, but in fact this is not so. The point is that both non-detonating explosives with a flame of long duration (like blackpowder) and those marked by high rate of detonation producing a violent shock-wave are unsafe. The safest explosives are those with intermediate properties, i.e., which give a not very high rate of detonation and lead block expansion, but in which the reaction of explosive decomposition proceeds much more quickly than in blackpowder, which burns or explodes relatively slowly. 

Alumina is a catalyst which shows intermediate behaviour and over which the concerted E2 mechanism is accepted [66] with slight transition either to the E2cA or E2cB mechanisms according to the structure of the reactant. Salts of strong acids and bases also show similar intermediate properties. The concerted or partly concerted mechanisms require two-site adsorption and because the mechanisms are ionic, the active centre must consist of a pair of an acidic and a basic site. Metal salts fulfil this... 

Pichat P, Guillard C, Maillard C, Amalric L, D Oliveira JC. Ti02 photo-catalytic destruction of water aromatic pollutants intermediates properties-degradability correlation effects of inorganic ions and Ti02 surface area comparisons with H202 processes. In Ollis DF, Al-Ekabi H, eds. Photo-catalytic Purification and Treatment of Water and Air. Amsterdam Elsevier, 1993 207-223. 

It is known from a variety of physical and chemical evidence that CO is a poor a donor and a good 7t acceptor, but the opposite is true of CN, while CNH can be expected to have intermediate properties. In a formal sense, carbon monoxide may be derived from the ligand CNH by coalescence of the nitrogen and hydrogen nuclei. The general observation, made in molecular spectroscopy, is that the electronic structure of a diatomic hydride resembles the combined atom more closely than the separated atoms. Thus, it is reasonable that the electronic structure of CNH will resemble CO more closely than CN-. This is also borne out by a semi-empirical self-consistent molecular orbital calculation, the results of which are summarized in Fig. 7. 

Of the compounds (1-4) above, only the ion (4) possesses cyclic delocalization and is aromatic. Compound (1) reacts mainly as an aliphatic disulfide, while compounds (2) and (3a-d) may have intermediate properties. 

The general chemistry of nitrogen donors classify them as donors of intermediate properties, considerably softer than the oxygen donors, as has already been stated. The connexion between chemical softness and thermodynamics so far found to be valid thus demands that both AH0 and dS° should be markedly lower for the formation of complexes by nitrogen than by oxygen donors. The data for complexes formed by ammonia and ethylenediamine presented in Tables 5 and 6, will show that this is true. 

Polymer Blends. Blending of polymers with each other accounts for approximately 40 percent of the present plastics market, and the practice is growing continually, because it permits the development of improved properties without the cost of inventing new polymers. When polymers are fairly miscible, as in the polyethylenes, and in polyphenylene ether plus polystyrene, blending can be used to produce intermediate properties and balance of properties. Most polymer blends... 

When a fluid passes through a packed column, the flow is divided due to the packing. Modelling of these phenomena is carried out by superimposing a dispersion, characterized by a coefficient D on the convective plug flow of velocity U. This is the model for an axial dispersion reactor. This model allows characterisation of a flow with intermediate properties between those of the plug flow reactor and those of a continuous stirred reactor. 

Colloidal solutions may be divided roughly into two main groups, designated as lyophobic (Greek solvent hating) and lyophilic (Greek solvent loving) when water is the dispersion medium, the terms hydrophobic and hydrophilic are employed. The chief properties of each class are summarized in Table 1.14, but it must be emphasized that the distinction is not an absolute one since some, particularly sols of metallic hydroxides, exhibit intermediate properties. 

Before concluding this discussion of cell walls, we note that the case of elasticity or reversible deformability is only one extreme of stress-strain behavior. At the opposite extreme is plastic (irreversible) extension. If the amount of strain is directly proportional to the time that a certain stress is applied, and if the strain persists when the stress is removed, we have viscous flow. The cell wall exhibits intermediate properties and is said to be viscoelastic. When a stress is applied to a viscoelastic material, the resulting strain is approximately proportional to the logarithm of time. Such extension is partly elastic (reversible) and partly plastic (irreversible). Underlying the viscoelastic behavior of the cell wall are the crosslinks between the various polymers. For example, if a bond from one cellulose microfibril to another is broken while the cell wall is under tension, a new bond may form in a less strained configuration, leading to an irreversible or plastic extension of the cell wall. The quantity responsible for the tension in the cell wall — which in turn leads to such viscoelastic extension — is the hydrostatic pressure within the cell. 

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