Preparation and thermal stability

M5Nb3OF g compounds can be prepared in the form of powder using the hydrofluoride method, according to the following interaction  

Using powder as a starting material, single crystals were grown from a solution of hydrofluoric acid containing appropriate concentrations of each type of compound (M = K or Rb), using the slow cooling method [206, 209, 211,438], 

At elevated temperatures, MsNb3OF18 compounds are sensitive to moisture. Upon heating in non-dry air, hydrolysis occurs at a temperature of above 5 5 OK, yielding hydrogen fluoride and two oxyfluoride compounds of different compositions, probably according to the following interaction [438]  

When thermal treatment is applied under conditions that prevent the hydrolysis of the compounds, partial decomposition takes place at a temperature above 600K. Extended thermal treatment at temperatures above 600K leads to complete decomposition according to the following process [438]  

The processes described in Equations (120 - 123) apply to both potassium- and rubidium-containing compounds (M = Kor Rb). 

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Gomez-Villacieros, R. Hernan, L. Morales, J. Tirado, J.L. (1987) Mechanochemical preparation and thermal stability of y- Fe203 derived from y-FeOOH. Mat. Res. Bull. 22 513-520... 

Reproducibility of the Sample Preparation and Thermal Stability of Thin Polymer Films... 

W. Schmidt, F. Schuth, H. Reichert, K. Unger, and B. Zibrowius, VPI-5 and Related Aluminophosphates Preparation and Thermal Stability. Zeolites, 1992, 12, 2-8. 

The data on washcoat preparation and thermal stability of the support are summarized in Table 2. The additive efficiency was defined as the ratio ... 

Jiang, W., Chen, S.H., Chen, Y. Nanocomposites from phenolic resin and various organo-modified montmorillonites preparation and thermal stability. J. Appl. Polym. Sci. 102, 5336-5343 (2006)... 

Inoue, A. Nishiyama, N. Kimura, H. (1997). Preparation and Thermal Stability of Bulk Amorphous Pd40Cu30Nil0P20 Alloy Cylinder of 72 mm in Diameter. Materials Transactions JIM Vol. 38, No. 2, (February 1997), pp. 179-183, ISSN 0916-1821 Inoue, A. (2000). Stabilization of metallic supercooled liquid and bulk amorphous alloys. 

Leonard V. Interrante and J. C. Bailar, Jr., Preparation and Thermal Stability of Azo and Axomethine Coordination Polyesters, Inorg. Chem. 3 1339 (1964). 

PREPARATION AND THERMAL STABILITY OF FLUOROALKYL END-CAPPED OLIGOMERS/SILICA NANOCOMPOSITES... 

Tang Y., Hu Y., Song L., Zong R., Gui Z., Chen Z., Fan W., Preparation and thermal stability of polypropylene/montmorillonite nanocomposites . Polymer Degradation and Stability, 2003 82 127-131. 

The thermally stable coordination polymers were prepared by the com-plexation of tetracarboxylic diimidates, such as pyromellic diimide (PMDI), with the salts of cobalt, nickel, copper, zinc, and mercury in DMF solution [43-46]. The linear coordination polymer of tetracarboxylic diimidate with zinc or mercury, is thermally stable above 550°C. Hojo et al. also reported the preparation and thermal stability of a series of aliphatic amine complexes of bivalent transition metals, such as cobalt, nickel, copper, zinc, and mercury, with tetracarboxylic acid diimidates [45]. 

There are ill-defined limits on EI/CI usage, based mostly on these issues of volatility and thermal stability. Sometimes these limits can be extended by preparation of a suitable chemical derivative. For example, polar carboxylic acids generally give either no or only a poor yield of molecular ions, but their conversion into methyl esters affords less polar, more volatile materials that can be examined easily by EL In the absence of an alternative method of ionization, EI/CI can still be used with clever manipulation of chemical derivatization techniques. 

In addition, NaOMe, and NaNH2, have also been employed. Applieation of phase-transfer conditions with tetra-n-butylammonium iodide showed marked improvement for the epoxide formation. Furthermore, many complex substituted sulfur ylides have been synthesized and utilized. For instance, stabilized ylide 20 was prepared and treated with a-D-a/lo-pyranoside 19 to furnish a-D-cyclopropanyl-pyranoside 21. Other examples of substituted sulfur ylides include 22-25, among which aminosulfoxonium ylide 25, sometimes known as Johnson s ylide, belongs to another category. The aminosulfoxonium ylides possess the configurational stability and thermal stability not enjoyed by the sulfonium and sulfoxonium ylides, thereby are more suitable for asymmetric synthesis. 

A series of phosphorus- and bromine-containing FRs were synthesized and studied to understand their role, especially their combined effects. Thus, monocar-danyl phosphoric acid, its bromo derivatives and their formaldehyde condensates and crosslinked products [28,188] were prepared and their properties compared with analogous products made from phenol [28,189]. Table 14 gives the LOI values, char yields (Cy at 600°C), and thermal stability at 50% (T6o) decomposition. 

PLA/PCL-OMMT nano-composites were prepared effectively using fatty amides as clay modifier. The nano-composites shows increasing mechanical properties and thermal stability (Hoidy et al, 2010c). New biopolymer nano-composites were prepared by treatment of epoxidized soybean oil and palm oil, respectively plasticized PLA modified MMT with fatty nitrogen compounds. The XRD and TEM results confirmed the production of nanocomposites. The novelty of these studies is use of fatty nitrogen compoimds which reduces the dependence on petroleum-based surfactants (Al-Mulla et al., 2011 Al-Mulla et ah, 2011 Al- Mulla et ah, 2010c). 

Optical fibres composed of plastics are also transparent in the visible spectral region but optical losses reach 102 - 103 dB/km13. Their refractive index varies from 1.35 to 1.6 depending on the kind of polymer used (e.g. polymethymethacrylate PMMA -1.49). The chemical resistance is much worse than that of silica fibres and thermal stability is incomparable. On the other hand, low temperature processes of plastic fibre preparation allow us mix the starting polymer with organic dyes which enables the production of luminescent fibres suitable e.g. for fluorescence-based sensing13. 

Ylide complexes of gold are unique in that they exhibit an exceptional chemical and thermal stability, which facilitates preparative and structural work very considerably. It was in this class of compounds that a large variety of true organogold(ll) and mixed valence organogold(l)/(lIl) complexes was discovered. These are rare in the remainder of organogold chemistry. 

Three poly(aryl ethers) were prepared and used as coblocks in imide copolymerizations. The first coblock prepared was poly(aryl ether phenylquinoxaline), since this material has the requisite high Tg ( 280 °C) and thermal stability, and the polymer can be processed from solution or the melt. The synthesis of po-ly(aryl ether phenylquinoxalines) involves a fluoro-displacement polymerization of appropriately substituted fluorophenylquinoxalines with bisphenols, us-... 

Recently, great attention has been dedicated to the development of novel synthetic procedures for the preparation of nanostructured catalysts with superior activity and thermal stability to those currently available. 

Linear [ ]-pol3turethane derived from 1-deoxy-l-isocyanate-2,3 4,5-di-(9-iso-propylidene-D-galactitol (prepared from 48) in the presence of TEA or Zr(acac)4, as well as its corresponding polyhydroxy derivative obtained by hydrolysis of the acetal protecting group, have been prepared [117]. They are semicrystalline materials that exhibit high melting temperatures and thermal stability up to 230°C. 

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