Papers by Keyword: Solid-Solid Reaction

Abstract: Based on the irreversible thermodynamics theory, the kinetic of BaSiO₃ solid-solid reaction has been constituted and then the equations were applied to BaSiO₃ solid synthesis reaction. The calculation results showed that the reaction was under control of reaction at 1207K.

Abstract: Synthesis hydroxyapatite (HA) powders from mollusc shell with the solid solution reaction method. The process is a new method which makes the amount of HA powder in large quantities. The advantage of the solid state method which involves molar ratio of calcium and phosphorus through a thermal treatment and reaction time, caused by the diffusion of ions in the solid particles. HA is the only apatite present in the reaction products, apart from minute fractions of certain other calcium compounds. The final product is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fourier transform infrared (FTIR)

Abstract: A computer software on solid/solid reaction kinetics, KinPreSSR, is one of subsystems in the software, Intellectualized Database Management System on Kinetics of Metallurgy (IDMSKM). KinPreSSR is a Windows application developed using Visual C++ and FoxPro, and includes two main modules, “DIFFUSION” and “REACTION”. KinPreSSR deals with the kinetics on the diffusion in solid state as well as solid/solid reactions. In the ‘REACTION’ module, the system has organized the commonly recognized kinetic models, parameters and employed both numerical and graphical methods for data analyses. The proper combination between the kinetic contents and the analytical methods enables users to use KinPreSSR for the evaluation and prediction of solid/solid reactions interested. The ‘DIFFUSION’ module includes two sub-modules of “database management system (DBMS)” and "Evaluation & prediction". The “DBMS” deals with the diffusion coefficients gathered from reported documents and the data evaluated according to some rules, besides, it can provide users with retrieval of diffusion coefficients. Based on the solutions to the Fick’s first law and the Fick’s second law in the four typical critical conditions, the "Evaluation & prediction" sub-module gives the predication of concentration distribution after diffusion process in solids or computation for diffusion coefficient.

Abstract: In the present study, three types of tetracalcium phosphate (TTCP) were prepared by solid-solid reaction or co-precipitation method and by different cooling modes. The effect of TTCP on the performance of calcium phosphate cement (CPC) was investigated. The result showed that the characteristic of TTCP varied with preparation method and played an important role in CPC performance. A solid-solid reacted TTCP yielded smaller particle size and resulted in bad workability and mechanical strength of CPC. The fast cooling of sintering TTCP by liquid nitrogen could avoid the decomposition of TTCP and make pure TTCP. TTCP prepared by wet-precipitation could improve performance of CPC and was promising to optimization of CPC.

Abstract: The carbothermal reduction synthesis process of titanium diboride (TiB2) particles was studied. In the synthesis of TiB2 using carbothermal reduction from a mixture of TiO2, B2O3 and carbon, solid-solid reactions occur. TiO2 particles rapidly react with carbon to TiC, which then reacts with boron oxide and carbon to TiB2. In the vacuum condition, TiB2 particles were formed within 10 minutes at temperature of 1300oC. It seems that a high exothermic reaction eventually results in the increase of reaction rate. In flowing argon atmosphere, TiB2 particles were formed at temperature of 1550oC after a reaction of 0 minute and it showed a finer particle size than that in the vacuum condition. This is attributed to the faster heat elimination due to the flowing argon. In high atmospheric pressure of argon gas such as 20 atm in reaction or cooling state, the synthesized TiB2 particles shows a mixture of diverse sized particles.