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Red mud is a solid waste produced during alumina extraction from bauxite. In this study, we pretreated red mud by segregation roasting to convert the iron from weak magnetic minerals to ferromagnetic minerals and then subjected the material to grinding and low intensity magnetic separation to obtain iron concentration. The effects of the chlorinating agent type, chlorinating agent dosage, reducing agent dosage, temperature, reaction time, additive, grinding fineness and magnetic field strength on the iron concentrate grade and recovery rate are studied. At a red mud/KCl/coke/ Na2SO4 mass ratio of 100:15:15:10, segregation roasting at 1100°C for 60 min, the roasted ore is ground to about 95 wt.% passing 0.045 mm and a magnetic field strength of 0.22 T, the final iron concentrate grade is 78.29% and the recovery is 84.08%, which is an efficient improvement of the valuable metal iron in red mud. The X-Ray Diffraction, Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy analysis of the iron concentrate shows that before the segregation roasting, the precious metal iron in the red mud is mainly in the form of Fe2O3. After the segregation roasting, the iron is transformed into a new iron mineral phase mainly composed of metal Fe and Fe3O4. The main impurities in the iron concentrate are calcium, silicon and aluminum. [ABSTRACT FROM AUTHOR]

Naviauxella phongsalyensis Sawada and Wiesner, 2004, and Neocollyris (Stenocollyris) compressicollis (Horn, 1909) are recorded for the first time for China, collected from southern Yunnan Province. From the same location specimens of Neocollyris (Neocollyris) jinpingi sp. nov. and Neocollyris (Leptocollyris) rogeri sp. nov. are described. Therates fruhstorferi fruhstorferi Horn, 1902, Cicindela (Cicindela) gemmata gemmata Falderman, 1835, and Tricondyla pulchripes White, 1844, occurring elsewhere in China, are reported as new records for Yunnan Province. [ABSTRACT FROM AUTHOR]

In 2009, a new citrus viral disease caused by Citrus yellow vein clearing virus (CYVCV) was first discovered in Yunnan province of China. In this study, a survey was conducted in 27 orchards from Yunnan province from April 2017 to September 2018. In all, 45 of a total of 513 citrus samples were tested positive for CYVCV by reverse transcription polymerase chain reaction (RT-PCR). Furthermore, the complete genome sequences of six CYVCV isolates from different hosts were sequenced. Comparisons of the whole genome sequences of these six CYVCV isolates as well as 34 isolates previously reported from around the world revealed the sequence identity ranged from 96.9% to 99.8% at nucleotide level, indicating that there is a very low level of sequence heterogeneity among CYVCV isolates of different hosts in Yunnan province. [ABSTRACT FROM AUTHOR]