Propylene glycol, atomized

Higher alcohols have more than three carbon atoms. Examples are the dihydric alcohol, ethylene glycol used for antifreeze, brake fluids and as derivatives in resins, paints " " osives, and polyester fibers. Reactions with propylene make propylene glycol, a moistening ag foods and tobacco. 

Diols are applied on a multimilhon ton scale as antifreezing agents and polyester monomers (ethylene and propylene glycol) [58]. In addition, they are starting materials for various fine chemicals. Intimately coimected with the epoxidation-hydrolysis process, dihydroxylation of C=C double bonds constitutes a shorter and more atom-efficient route to 1,2-diols. Although considerable advancements in the field of biomimetic nonheme complexes have been achieved in recent years, still osmium complexes remain the most efficient and reliable catalysts for dihydroxylation of olefins (reviews [59]). 

Chemical disinfectants are limited in their use as air sterilants because of their irritant properties when sprayed. However, some success has been achieved with atomized propylene glycol at a concentration of 0.05-0.5 mgH and quaternary ammonium compounds (QACs) at 0.075% m be used. For areas which can be effectively sealed off for fumigation purposes, formaldehyde gas at a concentration of 1-2 mg H of air at a relative humidity of 80-90% is effective. 

Mr. Wislicenus has, in fact, recently announced that he has found an active acid in meat. This acid does not have, as has been believed, the constitution of the ethylene lactic acid but it is according to this author a physical isomer of the ordinary lactic acid. Indeed one cannot see that the ethylene lactic acid can be active, for the carbons of the radical are each one combined with two atoms of hydrogen, as the formula shows CH2 OH CH2 GOOH. We see also that the propylene glycol and the iodopropionic acid which are derived from the active lactic acid will preserve the rotatory power, but it will not be the same with the glycerine which one can derive from it, for in that case the central carbon atom is united with the two equal radicals CH2 OH,... 

Chemical disinfectants are limited in their use as air sterilants because of their irritant properties when sprayed. However, some success has been achieved with atomized propylene glycol at a con-... 

Solvation due to chelate-type hydrogen-bond formation can also be observed in solutions of organic ligands made with non-aqueous solvents. Propylene glycol, for example, forms chelate-type hydrogen-bonds with deprotonated phenolate oxygen atoms in polypeptides, resulting in a decrease in their protonation constants [Bu 79, No 80] compared with those in water. 

A weak point of carboranes is their susceptibility to alkaline degradation. This weakness applies practically only to the species with adjacent carbon atoms. Thus, o-carborane is quantitatively converted to the nido-[7,8-C2B,H,j] ion within a few hours by sodium methoxide in ethanol or by sodium (or potassium) hydroxide in ethanol [50]. With m-carborane the same type of degradation proceeds at least 100 times more slowly and a temperature of at least 70 °C is required for any practical effect [51] the first observed degradation of the para isomer could only be forced using a 30% solution of potassium hydroxide in propylene glycol at 180 °C [52]. 

Poly(alkyleneoxy) compounds are chpacterized by a flexible array of donor oxygen atoms based on -CH(R)-CH2D-units and are regarded as acyclic ethers, e.g. PPG1025, a poly(propylene glycol). The tetraphenylborate (TPB)-barium complex of PPG-1025 with di-octylphenyl phosphonate constitutes a... 

The partial substitution of water in the solvent by propylene glycol favours the dimerisation process. This is reflected in an increase of the dimer formation constant and in the fact that the association of monomeric species containing unprotonated carboxylates and protonated amino groups is accompanied in water with the protonation of one carboxylate and in the solvent mixture with that of two. The dimer formation increases the protonation constants of these carboxylates showing that the dimerization of BPTI is due to the formation of intermolecular H-bonds in which these carboxylate-oxygens act as pillar atoms. Thus the pH dependence of the dimerization is determined by the protonation - deprotonation equilibria of these groups. The increased acidity of the other carboxyls in the solvent mixture may be due to the steric effect of the macro-molecular dimer. 

Huang, C., Wan, X., and Ying, S. (2000). S5mthesis of poly(propylene glycol-g-styrene) from atom transfer radical pol5merization. Gaofenzi Xuebao, 4 467-471. 

At first, they are heated in alkaline medium. The chlorine ions liberated from thiamphenicol are directly titrated by a standard silver nixate solution after acidification of the medium by nixic acid. The final point is detected by potentiomeXy. The indicator electrode is a silver electrode. In the cyclophosphamid case, the titration is carried out according to Charpentier-Volhard s method. For chlorambucil, the mineralization of chlorine atoms is performed in refluxing propylene glycol containing potassium hydroxide. 

Decomposition of the poly(propylene oxide) hydroperoxides into formate groups shows that hydroperoxidation occurs at the secondary carbon atom of the propylene glycol monomeric unit, rather than at the tertiary carbon. 

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