Ethanol measurements

Mole fraction profiles of C3H3 in a series of fuel-rich propene flames (C/O = 0.5) doped with ethanol, measured by EI-MBMS (left) and VUV-PI-MBMS (right). The inset shows the effect of ethanol addition on the peak mole fraction, normalized to the value in the undoped flame r, mole fraction, h. height. 

After refluxing, disconnect the trapping tube, and transfer the yellow solution into a 25-mL volumetric flask. Rinse the mbe with ethanol, and adjust the solution to volume with ethanol. Measure the absorbance of the solution at 435 nm against a blank prepared by diluting 15 mL of color reagent to 25 mL with ethanol. Determine the carbon disulflde content from a calibration curve obtained by plotting carbon disulfide concentrations of different standard solutions on the abscissa versus the absorbance on the ordinate. 

Wash the resulting solid with 10 mL of 50% aqueous ethanol. Measure the ethanol with a graduated cylinder. Pour off the liquid into the waste container. 

Unless otherwise indicated data taken from (7iPMH<3)67) which contains references to the original literature.bMeasured in ethanol. Measured in cyclohexane. dMeasured in isooctane cf. CHEC 4.26.2.4. e 2-Methyl-1,3,4-oxadiazole exhibits a maximum at 206 nm (log e 2.62) in MeOH cf. CHEC 4.23.2.2.2. f 5-Phenyl-1,2,3,4-thiatriazole. 

An alternative procedure is applicable when the 2,4-dinitrophenylhy-drazone is known to be sparingly soluble in ethanol. Measure 1 millimole (0.198 g) of crystalline 2,4-dinitrophenylhydrazine into a 125-mL Erlen-meyer flask, add 30 mL of 95% ethanol, digest on the steam bath until all... 

A small test device, Q.E.D. Saliva Alcohol Test (OraSure Technologies, Bethlehem, Pa.), has been developed to measure ethanol in saliva. Saliva is absorbed onto a swab, which is then inserted into the test cartridge. Ethanol measurement is based on an ADH reaction coupled with a diaphorase-mediated color indicator reaction, which provides for visual end-point detection on a thermometer-like scale after a 2-minute incubation. 

Water-soluble, heat-stable inhibitor of albumin-binding capacity, Mr < 10,000 has acidic group with pK = 4-5 Acidified serum applied to hydrophobic resin, eluted with ethanol, measured albumin binding of phenytoin and tryptophan... 

The experimental set-up and technique to fabricate columnar porous SiC are similar to the set-up used for triangular porous SiC. But, since we need to apply a high voltage (>10 V) and use a relatively concentrated HF electrolyte, the PECE experiments are conducted in a two-electrode cell where a SiC crystal is used as the anode. Aqueous 10% HF mixed with 5 % ethanol (measured by weight) electrolyte is used. Voltage is applied... 

The redox balance verified that missing product was with a high degree of reduction (5.7-5.9), confirming that the primary product missing is ethanol because the ethanol degree of reduction is 6. To validate the values of ethanol loss, ethanol evaporation rate was also determined experimentally in an experimental set-up identical to the one used for the WEH fermentations with medium containing 10 g/1 xylose and 10 g/1 ethanol. Measured ethanol concentrations in the effluent were used to estimate ethanol evaporation... 

In addition to multi-gas sensors, which are discussed later (see Section 10), direct-measuring O2 and IR sensors can be used for this kind of measurement. By use of fast O2 sensors, O2 and N2 wash-out curves are measurable whereas N2 is determined as a complement to 100%. Ethanol, acetone and SF5 can be measured by means of modified IR sensors. For the separation of interfering composites such as additional gases in sample blends like anesthetic gases in the case of ethanol measurements, an appropriate expenditure is required. 

Fig. 8.4. Drift correction of the sensor TGS 2620 by multiplicative factor estimated by ethanol measurements...

Ashraf, S., Blackman, C. S., Naisbitt, S. C. and Parkin, I. P. (2008) The gas-sensing properties ofW03-x thin films deposited via the atmospheric pressure chemical vapour deposition (APCVD) of WC16 with ethanol. Measurement Science and Technology 19,025203. 

Figure 5.47. Intensity dec of 9

Griddle WJ, Jones TP, and Parry KW (1989) A new approach to ethanol measurement in alcoholic beverages. Journal of the American Society of Brewing Chemists 47 1-3. 

In situ probes are often used in order to provide information about solid phases and to measure the solute concentration during batch solution crystallization experiments. For instance, Gagniere et al have qualitatively used an in situ video probe to monitor the evolution of single CBZ crystals and CBZ/NCT co-crystals in the slurry since the crystal habits of these two solid phases are largely different in ethanol. Measurement of the concentrations in solution of the two components of the co-crystal phase is very instructive about the competition between the metastable and stable phases. This monitoring is carried out most of the time using mid-infrared spectroscopy in ATR mode which provides estimates with time of the solute concentrations of the chemical components involved in the co-crystallization process. Three case studies taken from the literature are discussed hereinafter in order to present different situations. 

The efficiency results can be compared to a slope efficiency of 31% for rhodamine 6G when dissolved in ethanol measured in our system. 

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