Trimethylsilylation of alcohols and phenols were carried out under solvent-free conditions with hexamethyldisilazane (HMDS) using LaCoO3 perovskite. LaCoO3 as an efficient catalyst accelerated this reaction under milder condition. The advantages of this method are evident regarding, easy separation, low cost and low catalyst loading, lack of pollution, easy work-up, and selective protection of ...

Response surface methodology was used to optimize preparation of biocomposites based on poly(lactic acid) and durian peel cellulose. The effects of cellulose loading, mixing temperature, and mixing time on tensile strength and impact strength were investigated. A central composite design was employed to determine the optimum preparation condition of the biocomposites to obtain the highest tensi...

Divergent natural selection regimes can contribute to adaptive population divergence, but can be sensitive to human-mediated environmental change. Nutrient loading of aquatic ecosystems, for example, might modify selection pressures by altering the abundance and distribution of resources and the prevalence and infectivity of parasites. Here, we used a mesocosm experiment to test for interactive...

Underground excavation is a necessary process for constructing mines, tunnels and depots in granite rock mass. In this study, the numerical specimens were established by discrete element method confirmed laboratory experiments order to investigate peak stress, cracking development failure properties of pre-holed under coupled biaxial loading unloading conditions. The results show that, containi...

In the course of the evaluation of the stream cipher SOBER-t32 submitted to NESSIE, a correlation between initial states has been found for related keys. With high probability some sums of bits of the initial state after key loading do not change their value when a bit of the key is inverted. This holds also for the loading of frame keys. It is shown that the required condition for the frame ke...