Homogeneous proof

Thus, the BLEVE theory predicts that, when the temperature of a superheated liquid is below T, liquid flashing cannot give rise to a blast wave. This theory is based on the solid foundations of kinetic gas theory and experimental observations of homogeneous nucleation boiling. It is also supported by the experiments of BASF and British Gas. However, because no systematic study has been conducted, there is no proof that the process described actually governs the type of flashing that causes strong blast waves. Furthermore, rapid vaporization of a superheated liquid below its superheat limit temperature can also produce a blast wave, albeit a weak... 

The first unequivocal proof of feasibility of homogeneous polymerization free of termination and chain-transfer was reported in 1956, and the concept of living polymers and its ramifications were fully developed in those publications 2). Although the initial work dealt with anionic polymerization of styrene and the dienes, the underlying ideas were soon applied by other workers to a great variety of polymeric systems, as shown by the brief review of some of those developed recently. 

In principle, diluter technology accurate to 10 /rl or less would have been an option, and appropriately smaller sample amounts could have been taken at the third step (a reduction at step 1 would have entailed another proof of homogeneity and representativity if the number of crystals per sample became too small if unlimited material is available, reducing the sample... 

Meat grinder Hobart chopper Polytron homogenizer Explosion-proof blender and jars... 

Anionic polymerization techniques were also critical for the synthesis of a model cyclic triblock terpolymer [cyclic(S-fo-I-fr-MMA)] [196]. The linear cctw-amino acid precursor S-fr-I-fr-MMA was synthesized by the sequential anionic polymerization of St, I and MMA with 2,2,5,5-tetramethyl-l-(3-lithiopropyl)-l-aza-2,5-disilacyclopentane as the initiator and amine generator, and 4-bromo-l,l,l-trimethoxybutane as a terminator and carboxylic acid generator. Characterization studies of the intermediate materials as well as of the final cyclic terpolymer revealed high molecular and compositional homogeneity. Additional proof for the formation of the cyclic structure was provided by the lower intrinsic viscosity found for the cyclic terpolymer compared to that of the precursor. 

From the point of view of complex formation, homogeneity of mixed oxides accessible by means of Pechini-type routines could be a result of the emergence of mixed complex compounds where two different cations are bonded to one and the same anion. Such a conjecture formulated in Ref. [7] yet has no definite proofs, and no attempts have been made in order to quantify the very role of complex formation in Pechini-type syntheses. 

Only visual inspection of the reaction solution was made. Since the metals used, i.e., Ru, Os, Ir, Co, are heterogeneous Fischer-Tropsch catalysts, definite proof of the homogeneity of these systems must await detailed spectroscopic and kinetic measurements. 

However, DMF is a solvent for polyacrylonitrile and the polymerization occurs in a homogeneous medium for solutions containing 30 per cent monomer or less. This reduces the value of these experiments as an argument to show the influence of a matrix effect. Indeed the fact that auto-acceleration disappears when DMF is added to acrylonitrile was considered as a proof for the fact that precipitation of the polymer was the cause of autoacceleration. 

Figure 2.26 shows an alkoxide attack at co-ordinated CO giving a carboalkoxy complex, and a borohydride attack at co-ordinated CO in which the boron simultaneously acts as a Lewis acid. The BH3 complexation now stabilises the formyl complex that would otherwise be thermodynamically inaccessible. So far the latter reaction has only been of academic interest in homogeneous systems (it may be relevant to heterogeneous systems though proof is lacking). 

The occurrence of polarization signals during homogeneous hydrogenations can be regarded as proof of the transfer of both atoms of the former parahydrogen molecule, that is, they become transferred as a pair or in a pair-wise maimer. 

Czochanska, Z. et al., Direct proof of a homogeneous polyflavan-3-ol structure for polymeric proanthocyanidins. J. Chem. Soc. Chem. Commun. 375, 1979. 

---