Brill transition

A. S. Brill, Transition Metals in Biochemistry , Springer-Verlag, Berlin, 1977. 

At temperatures above 180 °C, an additional melt peak forms besides the original double peaks recognizable in DSC [776], [777], Figure 5.206. This phenomenon is credited to Brill transitions. The usual crystal shape of polyamides is triclinic the result of Brill transition is a pseudo-hexagonal shape induced by post-crystallization at temperatures above 180 °C [778]. 

TDI isomers, 210 Tear strength tests, 242-243 TEDA. See Triethylene diamine (TEDA) Telechelic oligomers, 456, 457 copolymerization of, 453-454 Telechelics, from polybutadiene, 456-459 TEM technique, 163-164 Temperature, polyamide shear modulus and, 138. See also /3-transition temperature (7)>) Brill temperature Deblocking temperatures //-transition temperature (Ty) Glass transition temperature (7) ) Heat deflection temperature (HDT) Heat distortion temperature (HDT) High-temperature entries Low-temperature entries Melting temperature (Fm) Modulu s - temperature relationship Thermal entries Tensile strength, 3, 242 TEOS. See Tetraethoxysilane (TEOS)... 

Many aliphatic poly(amides), more commonly known as nylons, exhibit an unusual phase transition below their melting point. First noted by Brill [122], the phenomenon has been studied extensively [128-131]. It is observed for instance in nylon (6,6) at a temperature of about 210°C, when the stable low-temperature triclinic oc phase of the crystalline polymer changes to a pseudo-hexagonal phase. 

Figure 15. Femtosecond dynamics of the Br + I2 - Brf + I exchange reaction. Here, the collision complex is long lived, tc = 53 ps. As shown by the molecular dynamics, the [Brill complex is trapped in the transition-state region the reaction may also involve avoided crossings (see text).

These Arbuzov-like reactions see Arbuzov Rearrangement) of phosphite ester transition metal complexes have been reviewed by Brill and Landon. ... 

Oyumi, Y. and Brill, T. B. (1985). Thermal decomposition of energetic materials. 6. Solid-phase transitions and the decomposition of 1,2,3-triaminoguanidinium nitrate. J. Phys. Chem., 89,4325-9. [284]... 

Brill, T. B., Landon, S. J. Arbuzov-like dealkylation reactions of transition-metal-phosphite complexes. Chem. Rev. 1984, 84, 577-585. 

Bao, Q. B., Brill, T. B. Methyl-group transfer involving transition-metal complexes by the Michaelis-Arbuzov mechanism. Organometallics 1987, 6, 2588-2589. 

Thus, Brill and Sandberg pointed out that whenever imidazole is coordinated to the ferriprotoporphyrin (H, 79, 82) the difference spectra of low-spin vs. high-spin complexes are characterized by an absorption band below 250 nm (A 236-23s approximately 6-12 X 10 M cm" ). Such a diagnostic band, attributable to charge transfer transitions from L5 to porphyrin orbitals, was noted in the difference spectrum of ferricata-lase cyanide (low spin) vs. catalase (high spin) 74), thereby favoring L5 = His. 

Brill AS (1977) Transition metals in biochemistry. Molecular Biology, Biochemistry and Biophysics, vol. 26. Berlin Springer. 

Ohtaki H, Yamaguchi T, Maeda M (1976) X-ray diffiaction studies of the stractures of hydrated divalent transition metal ions in aqueous solution. Brill Chem Soc Jap 49 701-708 Palmer BJ, Pfimd DM, Fulton JL (1996) Direct modeling of EXAFS spectra from molecular dynamics simulations. JPhys Chem 32 13393-13398... 

Brill, T.B. and Subramanian, R. Thermal Decomposition of Energetic Materials 35. A Mechanism Study of Decomposition and the Transition to the Ignition-Like State in Trinitromethyl Alkyl Compounds Combustion and Flame, in press. 

Oyumi, Y. and Brill, T.B. (1987) Thermal Decomposition of Energetic Materials 23. Thermochemicai Differentiation of Cyclic and Acyclic Nitramines by Their Phase Transitions Thermochimica Acta 1l6, 125-130. 

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