Mechano-chemical activation

Z.S. Wronski, Mechano-chemical activation of powders used in electrochemical power sources, In 50th ISE Mtg and Symposium on Electrochemical Power Sources after 200 years, Pavia, Italy. (1999). International Electrochemistry Society, Geneva, Switzerland. 

An alternative indirect method of the synthesis of Mg(AlH )2 is the mechano-chemically activated metathesis reaction which was first reported by Dymova et al. [115, 116] according to the following reactions between MgH, AlH and AICI3 during ball milling... 

The second attanpt to synthesize Mg(BH )j has been made in our laboratory by the mechano-chemical activation synthesis (MCAS) (or sohd state metathesis reaction) [175] according to the reaction of (3.37b). The starting powder mixture of as-received NaBH (98% purity) and anhydrous MgCl (99% purity) were mixed together in the 2 1 stoichiometric ratio with the objective of initiating the following metathesis reaction... 

R.A. Varin, Ch. Chiu, T. Czujko, Z. Wronski, Mechano-chemical activation synthesis (MCAS) of nanocrystalline magnesium alanate hydride [Mg(AlH ) ] and its hydrogen desorption properties , J. Alloys Compd. 439 (2007) 302-311. 

Of some interest are chelation processes occuring along with the synthesis of macromolecular ligands. This can be exemplified by a mechano-chemical activation of polyethylene terephthalate and en polycondensation to give the following complexes [112] ... 

Passerini N, Peiissutti B, Albertini B, Franceschinis E, Lenaz D, Hasab D, Locatelli I, Voinovich D (2012) A new approach to enhance oral bioavailability of Silybum Marianum dry extract Association of mechano-chemical activation and spray congealing. Phytomedicine 19 160-168. 

Carh F, Colombo I, TorriceUi C. Drug/p-cyclodextrin systems by mechano-chemical activation. Chimica Oggi 1987 5 61-64. 

Mechano-chemically activated forms of dicalcium silicate... 

It is obvious that the observed dramatic increase of the strength values cannot be explained merely by the increased fineness of the material, and that the mechano-chemical activation taking place in the course of grinding was essential for obtaining these high strength values. 

Gun ko, V.M., Zaulychnyy, Ya.V, Ilkiv, B.I. et al. 201 If. Textural and electronic characteristics of mechano-chemically activated composites with nanosilica and activated carbon. Appl. Surf. Sci. 258 1115-1125. 

Zhu De-qing, Pan Jian, Qiu Guan-zhou et al, Mechano-chemical Activation of Magnetite Concentrate for Improving Ifs Pelletability by High Pressure Roll Grinding, ISIJInternational, 44(2004),310-315. 

Powders mixing was performed in a SPEX 8000 (SPEX CertiPrep, USA) shaker mill for 30 min using plastic vials and alumina balls. Mechano-chemical activation of Ta-based mixtures was carried out using the same mill apparatus with two steel balls (13 mm diameter, 8 grams weight) for 20 min milling time interval and ball to powders or charge ratio (CR) equal to 1. 

The first attempt was aimed to synthesize the different UHTCs by SHS according to reactions (l)-(6), when starting from simply blended powder mixtures. While the ZrB - and HfB -based systems were found to clearly exhibit a self-propagating behaviour, both TS and TTS compositions did not. This fact could be readily explained on the basis of the relatively lower heat of reactions (3) and (6) (cf. Table 3). Thus, the mechano-chemical activation of the related starting reactants under the conditions reported in the experimental section was required to induce the SHS character in the synthesis reactions. 

Borides Ceramic compounds between boron and a less electronegative element. Carbides Ceramic compounds made of carbon and aless electronegative element. Mechano-Chemical Activation Ball milling treatment of a reactants mixture to increase its reactivity. 

Xiang, J. Y, Liu, S. C., Hu, W. T., Zhang, Y, Chen, C. K., Wang, P. et al. (2011). Mechano-chemically activated synthesis of zirconium carbide nano-particles at room temperature A simple route to prepare nano-particles of transition metal... 

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