Determination of Activation Parameters and the Thermal Stability of 1,2-Dioxetanes

Author(s):  
WALDEMAR ADAM ◽  
KLAUS ZINNER
2021 ◽  
Vol 15 (2) ◽  
pp. 271-277
Author(s):  
G. M. Nazin ◽  
B. L. Korsunskiy

1983 ◽  
Vol 19 (8) ◽  
pp. 412-414
Author(s):  
N. A. Kudryavtseva ◽  
I. A. Mikhailov ◽  
E. M. Nikonorov ◽  
L. A. Rakova

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Iwona Zarzyka

The work focuses on research related to determination of application possibility of new, ecofriendly boroorganic polyols in rigid polyurethane foams production. Polyols were obtained from hydroxypropyl urea derivatives esterified with boric acid and propylene carbonate. The influence of esterification type on properties of polyols and next on polyurethane foams properties was determined. Nitrogen and boron impacts on the foams’ properties were discussed, for instance, on their physical, mechanical, and electric properties. Boron presence causes improvement of dimensional stability and thermal stability of polyurethane foams. They can be applied even at temperature 150°C. Unfortunately, introducing boron in polyurethanes foams affects deterioration of their water absorption, which increases as compared to the foams that do not contain boron. However, presence of both boron and nitrogen determines the decrease of the foams combustibility. Main impact on the decrease combustibility of the obtained foams has nitrogen presence, but in case of proper boron and nitrogen ratio their synergic activity on the combustibility decrease can be easily seen.


1975 ◽  
Vol 147 (3) ◽  
pp. 593-603 ◽  
Author(s):  
D L Morris ◽  
J Campbell ◽  
W E Hornby

Triethyloxonium tetrafluoroborate was used to O-alkylate nylon-tube thus producing the imidate salt of the nylon which was further made to react with 1,6-diaminohexane. 2. Hexokinase (EC 2.7.1.1) and glucose 6-phosphate dehydrogenase (EC 1.1.1.49) were immobilized on the amino-substituted nylon tube through glutaraldeyde and bisimidates. 3. The effect of varying the conditions of O-alkylation and the amount of enzyme immobilized on the activity of nylon tube-hexokinase derivatives was determined. 4. The effect of varying the amount of enzyme immobilized on the activity of nylon-tube-glucose 6-phosphate dehydrogenase derivatives was determined. 5. The thermal stability of nylon-tube-hexokinase and nylon-tube-glucose 6-phosphate dehydrogenase derivatives was studied. 6. Different ratios of hexokinase and glucose 6-phosphate dehydrogenase were co-immobilized on nylon tube, and the rate of conversion of glucose into 6-phosphogluconolactone was compared with the individual activities of the immobilized enzymes. 7. Hexokinase and glucose 6-phosphate dehydrogenase co-immobilized on nylon tube were used in the automated analysis of glucose.


2001 ◽  
Vol 66 (11-12) ◽  
pp. 871-880 ◽  
Author(s):  
Vesna Miskovic-Stankovic ◽  
Zorica Lazarevic ◽  
Zorica Kacarevic-Popovic

The corrosion behaviour of epoxy coatings electrodeposited on aluminium, as well as on electrochemically and chemically modified aluminium were investigated during exposure to 3 % NaCl. Electrochemical impedance spectroscopy (EIS) and thermogravimetric analysis (TGA) were used for the determination of the protective properties of epoxy coatings on aluminium, anodized aluminium, phosphatized and chromatized-phosphatized aluminium. The protective properties of epoxy coatings on anodized and chromatized-phosphatized aluminium are significantly improved with respect to the same epoxy coatings on aluminium and phosphatized aluminium: higher values of the pore resitance and charge-transfer resistance, lower values of the coating capacitance, double-layer capacitance and relative permittivity (from EIS) smaller amount of absorbed water inside the coating (From TGA). On the other hand, the lower values of the ipdt temperature indicate a lower thermal stability of the epoxy coatings on anodized and chromatized-phosphatized aluminium.


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