Alcohols detection

Caminati, W., A. C. Fantoni, B. Velino, K. Siam, L. Schafer, J. D. Ewbank, and C. Van Alsenoy. 1987a. Conformational Equilibrium and Internal Hydrogen Bonding in 2-Methylallyl Alcohol Detection of a Second Conformer by Microwave Spectroscopy on the Basis of Ab Initio Structure Calculations. J. Mol. Spectrosc. 124, 72-81. 

Methyl alcohol. Methyl alcohol may be detected by the reactions indicated on p. 254. If the aqueous solution contains only methyl alcohol, or this with small quantities of acetone (for detection of acetone, see below, paragraph 3), the amount of this alcohol in 100 grams of the varnish may be deduced from the density of the distillate (see table, Vol. I, p. 40). If ethyl alcohol (detected as in paragraph 2) also is present, the methyl alcohol is determined either colorimetrically or by combustion (see p. 258). The amount thus found is deducted from the total alcohol determined from the density of the distillate by means of the ordinary tables for ethyl alcohol, the remainder being the amount of the latter alcohol.1... 

Ceric ammonium nitrate To 1 to 2 ml of 5% ceric ammonium nitrate add 10 drops of the compound to be tested. A change to an orange/red color is indicative of an alcohol (detection limit, 100 mg compounds tested, C, to C10). 

It is shown in [4] that the presence of two types of centres possessing the discriminate reductive-oxidation and acid-base properties and participating in transformation processes of an alcohol molecule is an essential requirement to achieve high sensor response values when alcohol detection is mentioned. Alcohol detection is considered as a multi-step process involving both red-ox and acid-base interactions. Oxide phases within composites differ by oxygen-oxide surface bonding energy which can be the relative measure of oxide activity in oxidation reactions. The reactivity of... 

Magnesium indium oxide (Mglu204) is a multication oxide having two types of cation centers possessing different reductive-oxidative and acid-base properties. Also, participating in the processes of the alcohol molecule transformation causes high sensor response when alcohol detection is considered. The centers of one type can suitably participate in adsorption-desorption processes of alcohol molecules, whereas complete oxidation of intermediates proceeds effectively at the centers of another type. 

Penza M, Cassano G, Aversa P, Antolini F (2004b) Alcohol detection using carbon nanotubes acoustic and optical sensors. Appl Phys Lett 85(12) 2379-2381... 

Arbiol J, Morante JR, Bouvier P, Pagnier T, Makeeva EA, Rumyantseva MN, Gaskov AM (2006) Sn02/Mo03-nanostructure and alcohol detection. Sens Actuators B 118 156-162... 

Figure 10.199 Determination of fatty alcohol detection suppressed conductivity injecdon ether sulfates in a dishwashing agent Separa- volume 50 pL sample diluted dishwashing tor column lonPac NS1,10pm eluent agent containing coco FAES (courtesy of...

It is stressed that the advantage of IPAD, in comparison to PAD, relates to minimization of baseline drift for oxide-catalyzed detections (Mode II). Comparisons of IPAD with PAD for carbohydrates at the oxide-free surfaces (Mode I) have indicated virtually no significant difference between the two techniques, and the continued use of PAD for carbohydrate and alcohol detections is recommended. 

In 1962, Inoue et al [140, 141], first succeeded in carrying out an asymmetric selective polymerization of /-propylene oxide (J,/-PO) using dialkylzinc-optically active (+)-borneol or (-)-menthol catalysts with a conversion of 30% (Scheme LVIII) the polymer was found to be optically active, levorotatory in benzene solution and dextrorotatory in chloroform, like the polymer obtained by Price [92] from the purified /-enantiomer monomer. There were no absorption bands corresponding to the original alcohol detected in the IR spectrum and the optical activity of the polymer must, therefore, be attributed to the prevalence of one of the two enantiomeric units. 

The Sbervegheri group used the sol-gel approach to prepare porous Ti02 thin films as electrical sensors for alcohol detection the synthesis entails the hydrolysis and condensation of tetraethyl orthotitanate in ethanol in the presence of water and HPC. This modified approach, compared with the standard sol-gel synthesis (without HPC), allows the deposited films to be crack-free and have a smaller nanoparticle size this enables much larger sensitivity (10-60 times) toward ethanol at temperatures between 400 and 500 °C, compared with the traditional sol-gel approach [86]. 

A range of acids and alcohols are generated from the different pathways detailed above, thereby providing potential substrates for esterification reactions. Many esters, most generally associated with fruity flavors, are found in fermented foods. LAB esterases can catalyze the formation of esters from acids and alcohols (Liu et al. 2004 Holland et al. 2005). In cheese, acids are present in relatively high concentrations (10 to 10" pg/g), while ethanol, the main alcohol detected (McGugan et al. 1975), is present in low amounts. Ethanol has been shown to be in concentrations limiting the synthesis of ethyl esters in cheeses such as Emmental (Richoux et al. 2008) and Cheddar cheese (Urbach 1995 Liu et al. 2004). 

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