Solid alcohol based on waste cooking oil: Synthesis, properties, micromorphology and simultaneous synthesis of biodiesel.

Solid alcohols based on waste cooking oil (WCO) and other edible oils (butter or soybean oil) were synthesized by a simple one-step method. The effects of sodium hydroxide (NaOH) dosage and type of oil on the combustion performances were explored. IR spectroscopy and micro-morphologies of the oil based solid alcohols were also studied. Results showed that, for oil based solid alcohol, use of an appropriate excess of NaOH and an oil with lower iodine value produced the solid alcohol with better combustion performance. Centrifugation produced the bottom waste cooking oil (B-WCO) with lower iodine value and the supernatant waste cooking oil (S-WCO) with higher iodine value. The B-WCO afforded solid alcohol with longer combustion time, higher melting temperature and relatively low combustion residue rate, whereas the S-WCO could be used for synthesizing biodiesel.

[The genetic relation of four ethnic populations in China's Guizhou is revealed by sequence variations of mtDNA D-loop].

OBJECTIVE: Through maternal inheritance, to explore the genetic structures and relationships of Dong, Gelao, Tujia and Yi ethnic population in Guizhou of China. METHODS: The mtDNA D-loop hypervariable segment I (HVS I ) in 108 samples of four ethnic populations were sequenced. Then, the nucleotide diversity was estimated and a phylogenetic tree was constructed by Neighbor-Joining method. RESULTS: In the detected 497 bp fragments, 86 polymorphic sites were found, and 82 different haplotypes were identified. The phylogenetic tree of four ethnic populations showed: Yi, Tujia and Gelao clustered more closely than Dong did. CONCLUSION: Yi and Tujia population are very closely related, the reason may be that they either originate from a common ancestry or frequently undergo the gene exchanges and admixtures. The genetic relationship between Tujia and Gelao population is nearer, perhaps because they have settled in the adjacent regions. Dong and Yi population show the farthest genetic relationship, this is probably due to their different historical origins and geographic segregation.