Synthesis and properties of 5-phenoxyfurancarboxylic acids

1980 ◽  
Vol 45 (3) ◽  
pp. 910-913 ◽  
Author(s):  
Viera Knoppová ◽  
Anton Beňo ◽  
Jaroslav Kováč
Keyword(s):  
Transfer Coefficient ◽  
Potentiometric Titration ◽  
Transfer Effect ◽  
Furan Series ◽  
Oxygen Bridge

Furancarboxylic acids were prepared by oxidation with Ag2O of the corresponding 5-(X-phenoxy)-2-furaldehydes (X = 4-OCH3, 4-SCH3, 3-NHCOCH3, 4-Cl, 4-Br, 4-COOC2H5, 3-NO2, and 4-NO2. The appearing pKa values of the synthesized acids were determined by potentiometric titration. The transfer effect of the substituents through the oxygen bridge is discussed and the transfer coefficient is compared with π' values of other linking groups in the furan series.

Secondary Transfer Effect of Contact

2009 ◽  
Vol 40 (2) ◽  
pp. 55-65 ◽  
Author(s):  
Thomas F. Pettigrew
Keyword(s):  
Cognitive Dissonance ◽  
Experimental Research ◽  
Intergroup Contact ◽  
Transfer Effect ◽  
Evaluative Conditioning ◽  
Transfer Effects ◽  
Secondary Transfer ◽  
Primary Reduction

This paper reviews the evidence for a secondary transfer effect of intergroup contact. Following a contact’s typical primary reduction in prejudice toward the outgroup involved in the contact, this effect involves a further, secondary reduction in prejudice toward noninvolved outgroups. Employing longitudinal German probability samples, we found that significant secondary transfer effects of intergroup contact exist, but they were limited to specific outgroups that are similar to the contacted outgroup in perceived stereotypes, status or stigma. Since the contact-prejudice link is bidirectional, the effect is inflated when prior prejudice reducing contact is not controlled. The strongest evidence derives from experimental research. Both cognitive (dissonance) and affective (evaluative conditioning) explanations for the effect are offered.

Evaporation of lignin-lean black liquor

TAPPI Journal ◽  
2015 ◽  
Vol 14 (7) ◽  
pp. 441-450
Author(s):  
HENRIK WALLMO, ◽  
ULF ANDERSSON ◽  
MATHIAS GOURDON ◽  
MARTIN WIMBY
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Black Liquor ◽  
Salt Content ◽  
Solubility Limit ◽  
Lignin Removal ◽  
Kraft Black Liquor ◽  
Black Liquors ◽  
The Heat Transfer Coefficient

Many of the pulp mill biorefinery concepts recently presented include removal of lignin from black liquor. In this work, the aim was to study how the change in liquor chemistry affected the evaporation of kraft black liquor when lignin was removed using the LignoBoost process. Lignin was removed from a softwood kraft black liquor and four different black liquors were studied: one reference black liquor (with no lignin extracted); two ligninlean black liquors with a lignin removal rate of 5.5% and 21%, respectively; and one liquor with maximum lignin removal of 60%. Evaporation tests were carried out at the research evaporator in Chalmers University of Technology. Studied parameters were liquor viscosity, boiling point rise, heat transfer coefficient, scaling propensity, changes in liquor chemical composition, and tube incrustation. It was found that the solubility limit for incrustation changed towards lower dry solids for the lignin-lean black liquors due to an increased salt content. The scaling obtained on the tubes was easily cleaned with thin liquor at 105°C. It was also shown that the liquor viscosity decreased exponentially with increased lignin outtake and hence, the heat transfer coefficient increased with increased lignin outtake. Long term tests, operated about 6 percentage dry solids units above the solubility limit for incrustation for all liquors, showed that the heat transfer coefficient increased from 650 W/m2K for the reference liquor to 1500 W/m2K for the liquor with highest lignin separation degree, 60%.

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