The effects of science,technology,society,environment(STSE)interactions on teaching chemistry

This study aimed to investigate the effects of making Science, Technology, Society and En-vironment relations on students’ comprehen-sion of chemistry topics through teaching che-mistry using STSE approach at secondary level. The study made use of the research model where pre and post tests were administered to control and treatment groups. The Chemistry Achievement Test (CAT) was used in the study. The sampling consisted of Grade 9 students studying at Anatolian High School and Voca-tional High School. Since the sampling had not been equated, in order to determine students’ logical and spatial thinking skills, they were administered Logical Thinking Skill Test and Mental Rotation test as pretests. Students were chosen randomly to take part in two control and two treatment groups. This experimental study was applied to the treatment group in teaching of “Separation of Mixtures” topic in Grade 9 Chemistry course during a four-week period. Students in the control group were taught through the traditional teaching methods. The data obtained were analyzed through the SPSS Software. As a result of the study, statistically significant increases were observed in the achievement levels of treatment group which received instruction using STSE relations. The change observed in the achievement levels of the control group was not statistically signifi-cant. The difference between the achievement levels of control and treatment groups in the posttests were favoring the treatment groups.

Phonon relaxation and heat conduction in one-dimensional Fermi Pasta Ulam β lattices by molecular dynamics simulations

The phonon relaxation and heat conduction in one-dimensional Fermi Pasta-Ulam （FPU） β lattices are studied by using molecular dynamics simulations. The phonon relaxation rate, which dominates the length dependence of the FPU β lattice, is first calculated from the energy autoeorrelation function for different modes at various temperatures through equilibrium molecular dynamics simulations. We find that the relaxation rate as a function of wave number k is proportional to k^1.688, which leads to a N^0.41 divergence of the thermal conductivity in the framework of Green-Kubo relation. This is also in good agreement with the data obtained by non-equilibrium molecular dynamics simulations which estimate the length dependence exponent of the thermal conductivity as 0.415. Our results confirm the N^2/5 divergence in one-dimensional FPU β lattices. The effects of the heat flux on the thermal conductivity are also studied by imposing different temperature differences on the two ends of the lattices. We find that the thermal conductivity is insensitive to the heat flux under our simulation conditions. It implies that the linear response theory is applicable towards the heat conduction in one-dimensional FPU β lattices.