Physico-chemical aspects of polyethylene processing in an open mixer. Part 19: Mechanisms and kinetics of vinyl and vinylidene group formation

2006 ◽  
Vol 91 (6) ◽  
pp. 1333-1345 ◽  
Author(s):  
F. Gugumus
Keyword(s):  
Group Formation ◽  
Physico Chemical ◽  
Kinetics Of

The effect of origin and physico-chemical properties on the kinetics of reduction of mixed NiO-Fe2O3 oxides with hydrogen

1986 ◽  
Vol 51 (10) ◽  
pp. 2098-2108 ◽  
Author(s):  
Milan Pospíšil ◽  
Jan Topinka
Keyword(s):  
Mixed Oxides ◽  
Mutual Influence ◽  
Spinel Phase ◽  
Chemical Properties ◽  
Inhibitory Effect ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Preliminary Annealing ◽  
Kinetics Of ◽  
Kinetics Of Reduction

We investigated the effect of origin and some physico-chemical parameters on the kinetics of reduction with hydrogen of two series of mixed NiO-Fe2O3 oxides differing by their composition, the character of their precursors (mixed crystalline nitrates and coprecipitated hydroxides) and their decomposition temperature.This effect manifested itself by different magnitudes of specific surfaces of the mixed oxides and coherent regions of present phases as well as by different oxidizing abilities of the surface and differences in morphology and phase composition of corresponding samples in both series investigated. Nonlinear or nonmonotonous composition dependences of physico-chemical parameters investigated point to a mutual influence of individual components, which is also a function of the system origin and which modifies its reactivity during its reduction with hydrogen. The kinetics of the reduction was studied thermogravimetrically at 320-410 °C. The reduction of oxides of the hydroxide origin is catalytically accelerated by primarily reduced nickel, whereas in corresponding samples of the nitrate series, the total NiO is bound to the spinel phase and the reduction is delayed. Experimental IR spectra, the effect of preliminary annealing and DTA of the mixed oxides point to an inhibitory effect of water, which is constitutionally bound in trace admixtures of the goethite phase, on the kinetics of reduction of samples in the hydroxide series.

scholarly journals Сitric acid influence on electroreduction processes in low concentrated Cu(NO3)2 solutions

2017 ◽  
Vol 5 (2) ◽  
pp. 136-143
Author(s):  
Alla Pravda ◽  
Vasil Larin
Keyword(s):  
Citric Acid ◽  
Ph Value ◽  
Reduction Reaction ◽  
Copper Electrodeposition ◽  
Nitrate Ions ◽  
Low Concentrations ◽  
Physico Chemical ◽  
Influence Of Ph ◽  
Kinetics Of ◽  
Cathode Reduction

Physico-chemical regularities citric acid influence on processes of copper and nitrate-ions reduction in low concentrated nitrate solutions were established. An influence of pH value on inhibitor action of low concentrations of the additive according to cathode reduction reaction of nitrate-ions, on kinetics of copper electrodeposition, on structure of the precipitates obtained was shown. Polarization measurements show us changes of copper electrodeposition at introduction of citric acid in Cu(NO3)2 solution. By the methods of traced elements and extraction into aqueous phase the reversible inclusion complexes into electrolytic copper, was established that proves participation of complexes in cathode process.

Kinetics of physico-chemical processes during intensive mechanical processing of ZnO–MnO2 powder mixture

2011 ◽  
Vol 323 (20) ◽  
pp. 2429-2435 ◽  
Author(s):  
M. Kakazey ◽  
M. Vlasova ◽  
M. Dominguez-Patiño ◽  
E.A. Juarez-Arellano ◽  
A. Bykov ◽  
...  
Keyword(s):  
Powder Mixture ◽  
Chemical Processes ◽  
Mechanical Processing ◽  
Physico Chemical ◽  
Kinetics Of

scholarly journals TIME-RESOLVED IMAGING SPECTROSCOPY OF PLANT ADAPTATIONS TO CHANGES IN THE LIGHT ENVIRONMENT AND APPLICABILITY TO SCREENING MUTANTS

HortScience ◽  
1994 ◽  
Vol 29 (4) ◽  
pp. 249b-249
Author(s):  
Sylvain L. Dubé ◽  
John F. Allen
Keyword(s):  
Energy Balance ◽  
Physiological State ◽  
Imaging Spectroscopy ◽  
State Transitions ◽  
Time Resolved ◽  
Growth And Survival ◽  
Plant Adaptations ◽  
Physico Chemical ◽  
Time Resolved Imaging ◽  
Kinetics Of

Photosynthesis, a major determinant in growth and survival of plants, is very sensitive to the energy balance of the processes triggered by the physico-chemical environment. It is, therefore, an excellent indicator of the plants' physiological state. Fundamental events in photosynthesis can be studied non-invasively and non-destructively by examining there-emission of absorbed light energy as chlorophyll a fluorescence. In this study we present digitized consecutive images of fluorescence of intact leaves of Arabidopsis sp. The relative intensity and kinetics of fluorescence of several AOI (areas of interests) of each image have been analyzed and compared. We demonstrate the feasibility of this technique for studying the physiology of light adaptations (state-transitions) of several organisms simultaneously and its applicability in indentifying mutants. Implications of this technique to the horticulture industry will be discussed.

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