Lactic acid density

PLA (NatureWorks PLA 3001D, 1.5% D-lactic acid, density = 1240kg/m ). 

Specific rotation is a physical property of a substance just as melting point boil mg point density and solubility are For example the lactic acid obtained from milk is exclusively a single enantiomer We cite its specific rotation m the form [a]o =+3 8° The temperature m degrees Celsius and the wavelength of light at which the measure ment was made are indicated as superscripts and subscripts respectively... 

Except for their effect on plane-polarized light, two enantiomers of a chiral compound have identical physical properties. For example, the two isomers of lactic acid shown below have the same melting point, 52°C, and density, 1.25 g/mL. 

Use Table 10.9 to determine the percentage deprotonation of 1.00 m aqueous lactic acid. At what temperature will the solution freeze (Assume that the density of the solution is 1.00 g-cm 3.)... 

The selective utilization of prebiotics by some, but not all, of the resident species alters the assemblages, densities and metabolic activities of the GIT bacteria. Of importance is the ability of prebiotics to increase the proportion of the resident bacteria represented by the lactic acid producing bacteria (LAB), resulting in changes of GIT and systemic functions (Swanson et al.. 

Sivakesava et al. also used Raman (as well as FT-IR and NIR) to perform a simultaneous on-line determination of biomass, glucose, and lactic acid in lactic acid fermentation by Lactobacillus casei.2 Partial least squares (PLS) and principal components regression (PCR) equations were generated after suitable wavelength regions were determined. The best standard errors were found to be glucose, 2.5 g/1 lactic acid, 0.7 g/1 and optical cell density, 0.23. Best numbers were found for FT-IR with NIR and Raman being somewhat less accurate (in this experiment). 

Lactic acid (2-hydroxypropionic acid, CH3CH0HC02H, boiling point 122°C, melting point 18°C, density 1.2060) is one of the oldest known organic acids. It is the primary acid constituent of sour milk and is formed by the fermentation of milk sugar (lactose) by Streptococcus lactis. 

Constant monitoring of both cells and medium is possible. However high levels of lactic acid accumulate at the high cell densities obtained and constant replenishment of the medium is essential together with use of a combination of Hepes and high bicarbonate to maintain the pH. 

Vauthier, C. Schmidt, C. Couvreur, P. Measurement of the density of polymeric nanoparticulate drug carriers made of poly(alkylcyanoacrylate) and poly(lactic acid) derivatives. J. Nanoparticle Res. 1999, 1, 411-418. 

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