Polyaspartic acid (PASP) is a biodegradable green material with carboxyl groups ( COOH) and amido groups ( CO NH ). In the article, a novel urea-formaldehyde (UF) resin modified by PASP and Ca-montmorillonite (Ca-Mt) was prepared by the alkalineacid-alkaline method. The synthesized materials were characterized by X-ray diffraction, Fourier transform-infrared spectroscopy, thermal analysis (TG-DTG), and scanning electron microscopy. The effects of viscosity, curing time, and free formaldehyde were investigated. The results showed that the layered structure of Ca-Mt was exfoliated and dispersed in the bulk of UF. The thermal stability of the modified UF was much better than that of pure UF resin. The percentage of free formaldehyde was declined from 26 to 18%. Meanwhile, the UF composites showed the short curing time and the optimum viscosity. Finally, a synthetic process of UF modified by PASP and Ca-Mt and a possible mechanism for immobilizing the free formaldehyde were suggested.

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With its unique square-shaped culm, Chimonobambusa hirtinoda C.S. Chao & K.M. Lan is a critically endangered species, and its natural habitat is solely restricted to Doupeng Mountain in Guizhou, China. Two small-insert libraries from C. hirtinoda were constructed and sequenced. Approximately 127.83 Gb of highquality reads were generated and assembled into 9,320,997 contigs with a N50 length of 213bp, thereby producing 8,867,344 scaffolds with total length of 2.01 Gb. An estimated genome size of C. hirtinode was 2.86 Gb on the basis of k-mer frequency analysis, with the GC content of 45.40%. The repeat rate and heterozygous ratio were 74.11 and 1.48% in C. hirtinoda genome, respectively. Finally, 65,398 SSR loci were identified in the assembled contigs, including 58.66% tri-nucleotide, 27.42% di-nucleotide, 7.94% tetranucleotide, 3.67% penta-nucleotide, and 2.31% hexa-nucleotide. Results of this study are useful not only for ecological conservation of C. hirtinoda, but also for phylogenetic studies.