Effect of the cool system on internal stress of CaO-Al2O3-SiO2 glass-ceramic system

Abstract

The samples were attained through altering the cooling system of producing glass-ceramics. The X-ray diffraction was used to test the stress value of different samples. The relation of the cooling system and internal stress were also investigated. The experimental results show that the stress of glass-ceramic had a close relation with starting cool temperature. Above 800 ℃, glass-ceramic could be accelerated cooling and did not bring stress. Temperature between 500 ℃ and 800℃ was an important temperature range of the formation of stress in glass-ceramic, in which the glass-ceramic stress would change obviously. Cool system was the key on how to control and eliminate internal stress in order to reduce the destroy of materials crated by internal stress. In addition, glass particles size increase, glass-ceramic stress increase in consequent.

Has China’s New Round of Collective Forest Reforms Reduced Forest Fragmentation? A Case Study of the Beijing–Tianjin–Hebei Region

“…In terms of social effects, most studies have concluded that NRCFT enhances the stability of property rights in forestland [43][44][45] and reduced the occurrence of forest rights disputes [46][47][48]. NRCFT has also promoted the transfer of forest rights and given rise to forestry cooperative organizations [49][50][51], which stabilized the basic rural management system [52].…”