The experiments show,when the ratio of fly ash to zirconium is 3∶1,the concentration of H2SO4 solution is 0.50 mol/L,the calcinating temperature is 550 ℃,the esterify efficiency of the FZS-G type fly ash compound solid acid catalyst which prepared in above conditions can reach to 98.3% when used in esterifiable reaction.
The experiment showed that the main fatty acids in the cell membrane——palmitic acid(16∶0),palmitoleic acid(16∶1),setearic acid(18∶0),oleic acid(18∶1),linoleic acid(18∶2) and eleosetearic acid(18∶3) could be separated completely by using the method of KOH CH 3OH BF 3 esterify ,silica gel decolorition and the programming calefaction.
The best ways to prepare copolyester was acid/glycol=1:1.6,esterify temperature 190-220℃ 4h, condensation polymerization temperature 250-260℃,3h by means of investigating the influence of reaction press and reaction time to polyester viscosity.
The esterify yield is up to 98.2% under the optimum conditions: propionic acid 0.15 mol, alcohol acid mole's ratio 1.2∶1, consumption of catalyst 0.25% (molar percent of propionic acid), reaction time for 3.0 h, 85～90 ℃, 5 mL cyclohexane. Copper methanesulfonate is used repeatedly for 8 times without obvious loss of activity and with the esterify yield still over 93.1%.
Glycol stearate was synthesized with the catalyst of p-aminobenzenesulfonic acid,the esterify reaction time,the alcohol/acid mole ratio,reaction temperature,the amount of the catalyst effect on the yield of product were tested,then obtain the optimum reaction condition:n(alcohol)∶n(acid)=1.3∶1,the amount of catalyst is 2.0 g,reaction temperature is 135 ℃,reaction time is 3 h,the yield may up to 92.6%.
It is proposed that mercaptocarboxylic acid ester free radicals can esterify PVC microradicals at carbon atoms with upaired electrons.
cyclopium do not esterify tertiary alcohols like many lipases.
Our results show that sterols can indeed be enriched in yeast by enhancing the capacity of the cells to esterify sterols.
These changes are more notable in the case of lecithins, varying not only with the substrate pH, but also with the length of the hydrocarbon chains of the fatty acids that esterify glycerol in the molecules of these substances.
The cultured skin fibroblasts had partially decreased sphingomyelinase activity and a greatly decreased ability to esterify exogenous cholesterol.
minnesota R595 LPS on LCAT activity was evaluated from the overall esterifying activity of serum using [1,2-3H2]cholesterol-labeled substrate.
Immobilization of the lipase on solid supports, such as Celite 545 (physical sorption) and Eupergit C250L (covalent binding), in the presence of hexadecane-1,2-diol was found to increase the esterifying activity of the enzyme.
The surface properties of fumed and precipitated silicas were modified by esterifying their surface silanol groups with methanol and hexadecanol.
The esterifying activity is also greatly influenced by the quantity and the lipid composition of lipoprotein substrate.
The esterifying alcohol of the bacteriochlorophyll a from Rhodospirillum rubrum was shown to be trans-trans-geranylgeraniol.