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In this paper, a new polymer-modified adhesive mortar is prepared using the fine iron tailings, eco-cement, redispersible latex powder, additives, and water. In our study, the fine iron tailings are used to replace the natural river sand as the mortar aggregate and the opti-mal process conditions are determined by the orthogonal experiment. The obtained results are shown as follows: The ratios of cement-sand and polymer-cement are 1:2.5 and 4%, respectively, with the aggregate modulus 0.81 and water reducing agent 0.5% (cement-based). The properties of the polymer-modified adhesive mortar obtained under the optimal process conditions conform to JC/T 547-2005 (China Professional Standard: Ceramic Tile Adhesive). Moreover, the microstructure of the polymer-modified adhesive mortar is studied and discussed. The results show that the network formed by the intertwined polymer film can prevent the merger of micro-cracks and improve the adhesive mortars' overall cohesion. Therefore, adding polymer to the adhesive mortar can improve its failure stress and enhance its bonding strength. [ABSTRACT FROM AUTHOR]

Astatotilapia burtoniis a species of fish in the Cichlidae family.Astatotilapia burtonihas been used as a model organism to research the behaviors and physical systems of cichlids. Here, we reported the complete mitogenome sequence ofA. burtoni, which was 16,583 bp and composed of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region, with a base composition of lower G + C content (45.5%). Similar toAstatotilapia calliptera, all genes were located on H-strand except for eight tRNAs andND6genes. Most protein-coding genes started with an ATG codon except forCOX1, ATP6andND3, which initiated with GTG or ATC instead, and terminated with the typical stop condon (TAA/TAG)or a single T. In this article, 12 protein-coding genes of other 10 closely species were used to construct the species phylogenetic tree to convince the mitogenome sequences. These results provided basic information for researchingA. burtonion genetics, phylogeny and adaptive evolution. [ABSTRACT FROM AUTHOR]