Heat Capacities Measurements on the Compounds of K2O-CaO-SiO2 System
The heat capacities of three ternary compounds, K2Ca2Si2O7, K4CaSi3O9, and K8CaSi10O25 are measured by this drop mode from MHTC96.The samples are prepared by Dr.V..Kahlenberg from University of Innsbruck of Austria.Dried K2CO3 (AlfaAesar, puratronic), CaCO3 (AlfaAesar, 99.995 ％) and SiO2 (AlfaAesar, 99.995 ％) are used as starting materials for the synthesis experiments.Each composition has been synthesized via solid state reactions.Thereafter, a stoichiometric mixture of the dried educts in themolar ratios based on the composition is homogenized in a planetary mill under ethanol, dry for several hours at 60 ℃ and pressed into pellets.The discs are subsequently heated in a platinum crucible covered with a lid from 300 ℃ to 900 ℃ with a ramp of 50 ℃/h, hold at this temperature for 78 h and eventually quench in air.A preliminary X-ray powder diffraction pattern of the product is applied to confirm that these samples are pure compounds.These samples are sensitive to environment, especially moisture, so they need to be used as soon as possible.And They are powders, however, in drop model,powder is not possible.Then, they should be press to pellets, which lead to these samples very fragile, it should handle very carefully during weighing and actual drop.
Ligang Zhang Libin Liu Stefan Guhl Zhanpeng Jin
School of Materials Science and Engineering, Central South University, Changsha, 410083;TU Bergakade School of Materials Science and Engineering, Central South University, Changsha, 410083
国内会议
桂林
英文
219-221
2015-11-03（万方平台首次上网日期，不代表论文的发表时间）