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Abstract  

The volume and enthalpy relaxation rate of inorganic glasses and organic polymeric materials subjected to temperature jump T has been analyzed. It is shown that the relaxation behavior in isothermal conditions can be compared on the basis of the fictive relaxation rate defined as R f=(dT f/dlogt)i. No significant difference between volume and enthalpy relaxation rate has been found for all materials examined. A simple equation relating the R f and parameters of Tool-Naraynaswamy-Moynihan (TNM) phenomenological model has been derived. This equation predicts increasing R f with the magnitude of temperature jump. It seems that correct determination of TNM parameters might be problematic for slowly relaxing polymers as the effect of these parameters becomes comparable with experimental uncertainty.

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Abstract  

A survey of materials science through our experiences shows that our knowledge of amorphous solids is quite poor compared with that of crystalline solids. Most pure substances can be obtained, in principle, as crystalline as well as non-crystalline states by physical and chemical methods. Destruction of the three-dimensional periodicity in crystalline substances will produce novel properties which cannot be anticipated from knowledge of crystal sciences. One direction of materials science in the coming century will surely be a new realm of amorphous condensed matter science.

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Abstract  

Amorphous solid of tri-O-methyl-β-cyclodextrin was produced by grinding its crystalline sample with a rod-milling machine at room temeprature. Structural and thermal characterizations of the sample during amorphizing process were done by X-ray powder diffraction and differential scanning calorimeter. The glass transition for a fully amorphized sample was found to occur at essentially the same temperature as that for a liquid-quenched glass. The heat capacities of the non-crystalline solids realized by grinding and liquid quenching and of the crystalline solid were measured by a low temperature adiabatic calorimeter. Excess enthalpies of the ground amorphous solid and liquid quenched glass over that of the hypothetical equilibrium liquid were determined calorimetrically. Similar and dissimilar thermal behavior of both non-crystalline solids were compared.

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Nanopages
Authors: I. Szendrő, K. Erdélyi, Zs. Puskás, M. Fábián, N. Adányi, and K. Somogyi

J. Domaradzki, A. Borkowska, D. Kaczmarek, E. Prociow, J. Non-Crystalline Solids 352 , 2324–2326 (2006). Prociow E. J. Non-Crystalline Solids

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. Ayers A. J. Hunt 2001 Synthesis and properties of chitosan-silica hybrid aerogels Journal of Non-Crystalline Solids

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. , Angeli F. , Cailleteau C. , Devreux F. , Frugier P. , Gin S. Investigation of gel porosity clogging during glass leaching , Journal of Non-Crystalline Solids , Vol. 354 , No. 45-46 , 2008 , pp. 4952 – 4958

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Central European Geology
Authors: Arnold Gucsik, Tasuku Okumura, Hirotsugu Nishido, Ildikó Gyollai, Kiyotaka Ninagawa, Natalie Deseta, and Péter Rózsa

. Sigel , G.H. , M.J. Marrone 1981 : Photoluminescence in as-drawn and irradiated silica optical fibers: An assessment of the role of non-bridging oxygen defect centers . – Journal of Non-Crystalline Solids , 45 , pp. 235 – 247

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Journal of Thermal Analysis and Calorimetry
Authors: J. J. H. Lancastre, F. M. A. Margaça, L. M. Ferreira, A. N. Falcão, I. M. Miranda Salvado, M. S. M. S. Nabiça, M. H. V. Fernandes, and L. Almásy

. 7. Schmidt , H 1985 New type of non-crystalline solids between inorganic and organic materials . J Non Cryst Solids 73 : 681 – 691 10

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crystallization kinetics of non-crystalline solids . J Non-Cryst Solids 320 : 84 10.1016/S0022-3093(03)00023-1 . 15. Budrugeac P , Criado JM , Gotor FJ , Málek J

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. Ngai , KL , Rendell , RW , Pye , LD , LaCourse , WC , Stevens , HJ 1992 The physics of non-crystalline solids Taylor and Francis London 309 – 342 . 26. Vilgis , TA

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