Solvents thermal

The oxidation may be carried out with an inert solvent thermally (35), with a sensitizer such as bromine (36), with uv radiation (37), or over a suitable catalyst (38). Principal by-products of all these oxidation processes are the acyl fluoride products derived from oxidative cleavage of the perfluoroaLkene (eq. 

Desorption of analyte using organic solvent Thermal desorption... 

Treatment of the l-(4,6-dimethylpyrimidin-2-yl)pyridinium-3-olate dimer 510 with l-dimethylaminobuta-l,3-diene and subsequent oxidation leads to the benzo dimer 511 which is converted to the regioisomer 512 by heating in an inert solvent. Thermal dissociation of the adduct 511 into the two betaines 513 and 514 was demonstrated by trapping these species with several... 

Saillard, R., Poux, M., Berlan, J. and Audhuypeaudecerf, M., Microwave-heating of organic-solvents -thermal effects and field modeling, Tetrahedron, 1995, 51, 4033. 

Carbon molecular Sieves 400-1200 Carbosieve, Ambersorb, Spherocarb Carboxen Solvent/ Thermal Non-polar and slightly polar VOCs (>- 80 °C) Low >400°C Low-medium... 

Of course, not all methods of cocrystal production require the use of auxiliary solvents. Thermal microscopy was used to determine if a particular carboxylic acid could cocrystallize with 2-[4-(4-chloro-2-fluorophe-noxy)phenyl]pyrimidine-4-carboxamide, with positive interactions being detected as crystalline material being produced at the binary interface [35]. Once identified, authentic cocrystal systems were prepared on a larger scale using solution-phase methods. In a similar study, hot-state microscopy was used to screen the possible interactions of nicotinamide with seven compounds of pharmaceutical interest that contained carboxylic acid groups [36]. A screening method for cocrystal formation based on differential scanning calorimetry has also been described, and used to demonstrate cocrystal formation in 16 out of 20 tested binary systems [37],... 

While vinyl acetate could be desorbed from the Chromosorb 107 using either heat or solvent, thermal desorption was investigated as the technique of choice. This eliminated the problem of finding a solvent which would not dissolve the Chromosorb 107, would quantitatively desorb the vinyl acetate, and contained no impurities which would interfere with the gas chromatographic analysis. Also, with this technique there was the possibility of having reusable collection devices. 

M = Ru and Os only) SiM-MSi units. The reactions were carried out in sealed tubes in the absence of solvent or in hydrocarbon solvents, thermally or under uv irradiation. 

Octacarbonyidicobalt is an orange, crystalline solid which decomposes to the purple cobalt(II) oxide or carbonate upon exposure to the air. It can be purified by sublimation at 25°C/0.1 mm, and it is soluble in hydrocarbon solvents. Thermal decomposition of octacarbonyidicobalt yields dodecacarbonyltetracobalt this decomposition is slow at 25°C but is quite rapid at 50°-60°C. Continued heating of the compound ultimately yields cobalt metal. 

When the excited state of the donor has a higher vibrational energy than the surrounding medium,e.g.solvent, thermal relaxation occurs in a very short time of 10 5-10 12... 

Post-synthesis solvent-thermal treatment. Alcohol-thermal treatment can enlarge the pore size of SBA-15 and improve its crystallinity . 

Polymer-solvent mixtures can be separated and the polymer recovered from solution at the lower critical solution temperature (LCST). This is the temperature at which the miscible polymer-solvent mixture separates into a polymer-rich phase and a solvent-rich phase. LCST phenomena are related to the chemical nature of the mixture components, the molecular weight of the mixture components, especially the polymer, and the critical temperature and critical pressure of the solvent (Allen and Baker, 1965). As the single-phase polymer solution is isobarically heated to conditions near the critical point of the solvent, the polymer and solvent thermally expand at different rates. This means their free volumes change at different rates (Patterson, 1969). The thermal expansion of the solvent is much greater than that of the polymer. Near its critical point, the solvent has expanded so much that it is no longer able to solubilize the polymer. Hence, the polymer falls out of solution. If the molecular weight of the polymer is on the order of 10 a polymer-solvent LCST can occur within about 20-30°C of the solvent s critical temperature. If the molecular weight of the polymer is closer to 10, the LCST phase... 

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