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CuBi2O4 is widely used in photocatalytic degradation for pollutants in water due to its strong visible light response characteristics, excellent chemical stability, non-toxic, and low cost. Here, stone-shaped CuBi2O4 was prepared with CuO and Bi2O3 as raw materials by high temperature solid phase. The effect of calcined temperature and time on the product was discussed. This material was analyzed and discussed by XRD, SEM, XPS, and DRS, and the visible light activity of degradation for Orange II was explored. The results showed that the absorption edge of prepared CuBi2O4 expands to the visible region, and the band gap was about 1.77 eV. The photocatalytic degradation rate of Orange II was 42.6% under the optimal conditions. After H2O2 assisted, the degradation rate was more than 2 times, and repeated experiments verified that the prepared catalysts had high stability. Finally, a reasonable mechanism of H2O2 assisted degradation enhancement is proposed. This work gives new ideas for the preparation of new and efficient catalytic materials. [ABSTRACT FROM AUTHOR]

Two types of retrograded eclogite (phengite‐bearing eclogite and garnet pyroxenite) within eclogite‐facies granitic gneisses are reported for the first time from the Younusisayi area of the South Altyn high to ultrahigh pressure (HP–UHP) metamorphic belt. These eclogites were studied using petrology, mineral chemistry, phase equilibrium modelling, and geochronology. The phengite‐bearing eclogite records five stages of metamorphism: (1) early prograde (Grt + Cpx + Amp + Rt + Qz) at conditions of P = 11.50–17.5 kbar, T = 665–740°C; (2) peak eclogite‐facies (Grt + Omp + Ph + Rt + Qz) at conditions of P > 24.2 kbar, T = 710–1000°C; (3) overprinting during retrograde transition to HP granulite‐facies conditions (Grt + Cpx ± Kfs + Pl + Rt + Qz) at P = 12.1–16.9 kbar and T = 760–890°C; (4) retrogression at granulite‐facies conditions (Grt + Cpx + Amp + Pl + Ilm + Qz) of P = 9.1–11.4 kbar, T = 730–840°C; and (5) amphibolite‐facies metamorphism (Amp + Pl + Ilm + Qz) during cooling and decompression. The garnet pyroxenite records four stages of metamorphism: (1) eclogite‐facies at conditions of P > 23.2 kbar, T = 775–965°C; (2) HP granulite‐facies conditions of P = 13.2–17.8 kbar and T = 836–912°C; (3) granulite‐facies conditions of P = 8.6–9.7 kbar, T = 739–783°C; and (4) amphibolite‐facies metamorphism. Zircon U–Pb dating and trace element analysis constrain eclogite‐facies metamorphism to c. 500 Ma, consistent with the age of the surrounding eclogite‐facies granitic gneiss (497.8 ± 2.7 Ma). Retrograde metamorphism ages of c. 460 Ma are interpreted as recording zircon growth after granulite‐facies metamorphism. The P–T–t path defines the integrated process of deep subduction and multistage exhumation and places constraints on the early Palaeozoic geodynamics of the South Altyn belt. Well‐preserved major and trace element zoning of garnets in the Ph‐bearing eclogites lacks evidence of significant thermal diffusion and may record garnet growth during deep subduction, immediately followed by very rapid exhumation. [ABSTRACT FROM AUTHOR]