Physical and Chemical Transformations of Kaolinite Caused by Flash Calcination

1995 ◽  
pp. 61-72
Author(s):  
T. W. Davies ◽  
R. C. T. Slade
2011 ◽  
Vol 496 ◽  
pp. 50-54
Author(s):  
Jimsher N. Aneli ◽  
Elena F. Semiletova ◽  
Nana V. Bakradze ◽  
Teimuraz N. Dumbadze

Abstract: Formation of electrical conducting channels with paramagnetic properties on the surface of three type polymer plates (phenol-formaldehyde and epoxy resins, polyacrylonitrile) under influence of CO2 laser irradiation at the presence of air have been studied. It is shown that the magnitude of surface resistance of the investigated polymers depends on polymer type and irradiation energy. The appearance of electrical conducting regions in the polymer materials is due to laser-chemical transformations of macromolecular physical and chemical structures near the polymer plate surfaces, leading to formation of double conjugated bonds. These structures are characterized also with paramagnetic properties- by method of ESR the free radicals are discovered in the transformed regions of polymers. The obtained results practically are analogous to ones obtained in such polymers after thermal treatment at high temperatures. However there are some advantages: in the latter case for obtaining of conducting materials on the base of dielectric polymers it is necessary to use a high vacuum. Besides of such method does not allow the formation of conducting channels with desired square and configuration on the surface of polymer plates in very short time (about several seconds) at present of air.


2017 ◽  
Vol 19 (9) ◽  
pp. 6497-6507 ◽  
Author(s):  
David M. Bell ◽  
Dan Imre ◽  
Scot T. Martin ◽  
Alla Zelenyuk

Chemical transformations and aging of secondary organic aerosol (SOA) particles can alter their physical and chemical properties, including particle morphology.


2009 ◽  
Vol 11 (36) ◽  
pp. 7853 ◽  
Author(s):  
Evan G. Robertson ◽  
Chris Medcraft ◽  
Ljiljana Puskar ◽  
Rudolf Tuckermann ◽  
Chris D. Thompson ◽  
...  

2010 ◽  
Vol 660-661 ◽  
pp. 692-696 ◽  
Author(s):  
M.A. Silva ◽  
J.N.F. Holanda

Aluminous electrical porcelains are used in the production of materials of high voltage insulators. The microstructure plays an important role in the performance of electrical porcelain. On the other hand, the porcelain materials undergo a series of physical and chemical transformations during firing. This makes the understanding of their microstructures rather complex. In this work was studied the microstructural development of electrical porcelain containing up to 35 wt.% of ornamental rock waste. The pieces ceramics were pressed at 50 MPa and sintered at 1300 °C. The porcelain pieces were characterized via X-ray diffraction and scanning electron microscopy. The results indicate that the presence of the ornamental rock waste influenced the microstructural development of the pieces of electrical aluminous porcelain.


2020 ◽  
Vol 21 (5) ◽  
Author(s):  
Dattatray Modhave ◽  
Isha Saraf ◽  
Anjali Karn ◽  
Amrit Paudel

2008 ◽  
Vol 47-50 ◽  
pp. 25-28 ◽  
Author(s):  
Valeriy V. Sobolev ◽  
S.M. Usherenko

The results of experimental research of physical and chemical transformations in a ferrous target, caused by intensive deformation mobility of its structural elements for times of shock-wave treatment (∼10–3 sec), at simultaneous development of process of superdeep penetration of lead microparticles are represented.


The fundamental difference of the developed defining equations is that they consider the dual system of porosity and kinetic laws of physical and chemical transformations to describe individual stages of corrosion processes. The dual porosity system comprises through capillaries (pores) of the longitudinal direction and adjacent capillaries of the transverse direction. During the reagent mass transfer in through capillaries (pores) there takes place their transfer to transverse ones, in which we can observe the neutralization (dissolution) reaction of chemically active substances in solid phase with the formation of the moving boundaries. The binding and release rate in case of leaching are determined from the respective boundary value problems and are similar in structure. In defining equations, all parameters are reduced to two generalized ones. Their values for forecasting the technical condition of operating structures are to be determined on the basis of concentration distribution of the aggressive component in concrete layer depth in the above-specified structures.


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