Unconventional quasiparticle excitations in condensed matter systems have become one of the most important research frontiers. Beyond twofold and fourfold degenerate Weyl and Dirac fermions, threefold, sixfold, and eightfold symmetry protected degeneracies have been predicted. However they remain challenging to realize in solid state materials. Here the charge density wave compound TaTe 4 is proposed to hold eightfold fermionic excitation and Dirac point in energy bands. High quality TaTe 4 single crystals are prepared, where the charge density wave is revealed by directly imaging the atomic structure and a pseudogap of about 45 meV on the surface. Shubnikov-de Haas oscillations of TaTe 4 are consistent with band structure calculation. Scanning tunneling microscopy/spectroscopy reveals atomic step edge states on the surface of TaTe 4 . This work uncovers that the charge density wave is able to induce new topological phases and sheds new light on the novel excitations in condensed matter materials.

A novel, efficient, and accurate fingerprinting method using high performance liquid chromatography-photodiode array detection has been developed and optimized for the investigation and demonstration of the variance in chemical properties among Siraitia grosvenorii fruits from different origins. The effects of growth stages, cultivated varieties, collection locations, and fruit portions of the herb on chromatographic fingerprints were examined. Eleven compounds were identified on chromatograms by comparing the retention time and UV spectrum of each peak separately with those of external references. The results revealed that chromatographic fingerprints, combining similarity or hierarchical clustering analysis along with reference compounds, could efficiently identify and distinguish S. grosvenorii fruits from different sources, which provided helpful clues for studying the plants' secondary metabolites and benefitted quality control.

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