As a key to realize the chemical looping air separation (CLAS) process, CuO is a good oxygen carrier candidate because of its high oxygen transport capacity and excellent thermodynamic characteristics. However, it is hampered by easy deactivation during redox cycles. In this work, a Cu−Zr oxygen carrier is developed via a metal−organic framework (MOF) self-templated method to realize high redox reactivity and favorable thermal stability for the CLAS process. The physicochemistry property and reduction kinetics are investigated through isothermal redox cycles, material characterizations, and reduction kinetic modeling. Compared to the coprecipitated oxygen carrier (Copr.), the MOF-derived oxygen carrier (MOF-D) obtains a 35% faster average reaction rate at the temperature interval of 800−900 °C, especially a 60% reduction rate increase at 850 °C. This enhanced reaction rate is mainly ascribed to the lower intrinsic activation energy (126.3 kJ•mol −1 for MOF-D vs 157.3 kJ•mol −1 for Copr.) rather than the amount of active oxygen species. The oxygen-releasing mechanisms for the MOF-derived and coprecipitated oxygen carriers follow the nucleation and nuclei growth model with a transition of one-dimensional growth to two-dimensional nucleation at two temperature ranges (800−825 and 850−900 °C). This study offers a new route to develop an efficient oxygen carrier for the CLAS process.

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Objective. This nationwide, multicenter prospective observational study with a patient registry was designed to evaluate the efficacy of Fufang E’jiao Jiang (FEJ) in Chinese patients with Qi and blood deficiency syndrome (QBDS). Methods. QBDS patients were consecutively recruited from 81 investigational sites in China from July, 2019, to December, 2020. Patients who met the eligibility criteria were enrolled in a prospective registry database. Baseline characteristics and changes in scores on the traditional Chinese medicine (TCM) symptom evaluation scale for Qi and blood deficiency, the clinical global impression (CGI) scale, the fatigue scale-14 (FS-14), and the Pittsburgh sleep quality index (PSQI) were analyzed to determine the clinical efficacy of FEJ. Results. A total of 3,203 patients were recruited. The average remission rate (i.e., the sum of the cure rate and improvement rate) of the 20 symptoms of QBDS was 92.49% after 4 weeks of FEJ treatment, which was higher than at baseline; the rate increased to 94.69% at 8 weeks. The CGI scale revealed that the number of total remissions at 4 and 8 weeks was 3,120 (97.41%) and 415 (100%), respectively. The total FS-14 scores decreased by 1.67 ± 4.11 ( p < 0.001 ) at 4 weeks and 1.72 ± 3.09 ( p < 0.001 ) at 8 weeks of treatment. The PSQI scores were 6.6 ± 4.7 and 6.52 ± 3.07 at 4 and 8 weeks, respectively, which were significantly lower than the baseline scores ( p < 0.001 ; p = 0.0033 ). Both the subhealth fatigue (SF) and iron deficiency anemia (IDA) groups showed significantly improved clinical symptoms of QBDS ( p < 0.01 ). Between-group comparisons revealed significantly greater improvements in FS-14 and PSQI scores in the SF group than in the IDA group ( p < 0.05 ). A multivariate logistic regression analysis showed that disease course, FS-14 score at baseline, and four-week FEJ doses were independent risk factors for the degree of symptom relief in QBDS patients ( p < 0.05 ). Conclusion. In real-world settings, FEJ has a promising effect in treating QBDS and can significantly improve the severity of its symptoms.