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Eucalyptus globulus is widely introduced and cultivated in Yunnan province. Its foliage is mainly used to extract eucalyptus oil, but the by-product eucalyptus residue has not been fully utilized. Based on the above reasons, in this study, we sought to explore the comprehensive utilization potential of eucalyptus resources. The total composition of eucalyptus residue was analyzed by ultra performance liquid chromatography-time-of-flight mass spectrometry (UPLC-Q/TOF MS), and the active components and nutrient components of eucalyptus leaf residue were determined by chemical methods and liquid phase techniques. Meanwhile, the antitumor activity of triterpenoids in eucalyptus leaves was evaluated by tetramethylazazole blue colorimetric assay (MTT). The results of qualitative analysis indicated that 55 compounds were identified from eucalyptus residue, including 28 phloroglucinols, 17 terpenoids, 3 flavonoids, 5 fatty acids, 1 amino acid and 2 polyphenols. Among them, the pentacyclic triterpenoids, in eucalyptus residue, were mainly oleanane type and urthane type. The results of quantitative determination indicated that the content of triterpenoid compounds was 2.84% in eucalyptus residue, which could be enhanced to 82% by silicone separation. The antitumor activity results showed that triterpenoid compounds have moderate inhibitory effects on human breast cancer cell MDA-MB-231, gastric adenocarcinoma cell SGC-7901 and cervical cancer cell Hela. The half maximal inhibitory concentration (IC50) was 50.67, 43.12 and 42.65 μg/mL, respectively. In this study, the triterpenoids from eucalyptus leaf residues were analyzed to reveal that the triterpenoids from eucalyptus leaf have antitumor effects and have potential to be developed as antitumor drugs. [ABSTRACT FROM AUTHOR]

In order to give full play to the alkaline neutralization value of carbide slag and reduce the environmental hazards of carbide slag, it is of great practical significance to study the resource utilization of carbide slag. The adsorption of sulfur compounds on carbide slag was studied in the laboratory, and the process parameters of carbide slag desulfurization were explored and optimized. The specific surface area, pore distribution, and other physicochemical parameters were analyzed by XRD and SEM, which explained the changes of products and carbide slag before and after desulfurization. The test results show that carbide slag and limestone have almost the same desulfurization effect. The kinetics of carbide slag desulfurization process conforms to pseudo-first-order kinetics, and the sulfur content of calcium carbide slag reaches to 1000 mgSO2·g−1. A project demonstration was carried out in the gold smelting Tielu Plant of Zhenyuan Huashuo Precious Metals Development Co., Ltd., in Yunnan. The results of the 2-year demonstration project showed that the desulphurization efficiency of the four-stage series desulphurization tower exceeds 95%. The concentration of sulfur dioxide in the discharged flue gas is reduced to less than 20 mg·m−3, which meets the requirements of ultra-low emission standard in China. Therefore, whether from theoretical research or engineering practice analysis, it is feasible to replace limestone with calcium carbide slag for flue gas desulfurization. The paper also discusses the problems existing in the demonstration project, and provides a new idea of "using waste to treat waste" in order to solve the problem of carbide slag disposal. [ABSTRACT FROM AUTHOR]

The Beiya porphyry‐skarn Au deposit is one of the largest gold deposits in China, temporally and spatially associated with Eocene intrusions in a post‐collisional setting in western Yunnan, China. In this study, we report new whole‐rock geochemistry, Sr‐Nd isotope, zircon U‐Pb geochronology and in situ zircon Hf‐O isotopes of quartz‐monzonite and biotite‐monzonite porphyries from the Beiya deposit. The porphyry‐skarn mineralization at the Beiya deposit is mainly associated with the quartz monzonite porphyry (35.8 ± 0.6 Ma), while the biotite‐monzonite porphyry (34.3 ± 0.5 Ma) represents a post‐mineralization intrusion crosscutting the main orebodies and the quartz‐monzonite porphyry. Both intrusions have high‐K and adakitic composition and are characterized by high Sr/Y ratios, high SiO2 and Al2O3 concentrations (SiO2 = 69.80–73.86 wt%; Al2O3 = 14.11–15.19 wt%), and low MgO, Cr, and Ni concentrations (MgO = 0.2–1.0 wt%; Cr = 1.76–11.13 ppm; Ni = 2.52–11.72 ppm). Their Sr‐Nd isotope compositions (87Sr/86Sr = 0.7066–0.7077; εNd(t) = –5.3 to –1.5) are consistent with the lower crustal‐derived amphibolite xenoliths (87Sr/86Sr = 0.7060–0.7100; εNd(t) = –10.0 to 0.0), indicating that they might be derived from a thickened juvenile lower crust beneath the Yangtze Craton. The biotite‐monzonite porphyry has lower zircon δ18O values of +5.3‰ to +6.8‰ and higher εHf(t) values of –2.3 to +5.5 than those of the quartz‐monzonite porphyry with δ18O values of +7.1‰ to +8.2‰ and εHf(t) values of –3.8 to +1.5, implying that they were derived from different parts of the lower crust. High Ba/La and Pb/Ce ratios suggest that the quartz‐monzonite porphyry is derived from a volatiles‐rich reservoir. Relatively higher La/Yb, Sm/Yb and Dy/Yb ratios of the biotite‐monzonite porphyry indicate residual garnet in the source, indicating a deeper source than that of the quartz‐monzonite porphyry. The hydrous components should be represented by the amphibole‐rich lithologies, which has relatively shallower depth than that of the garnet‐bearing mafic thickened lower crust. Our data suggest that the mineralized quartz‐monzonite porphyry at the Beiya deposit is derived from partial melting of amphibole‐rich lithologies in the upper part of the thickened juvenile lower crust beneath the Yangtze Craton, while the post‐mineralization biotite‐monzonite porphyry is derived from the basal, and volatiles‐poor, part of the juvenile lower crust. [ABSTRACT FROM AUTHOR]