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La-deficient La1-xCexMnO3 mixed oxides, obtained by selective dissolution in 1 ​M nitric acid, were employed in methane complete oxidation. The majority of the La cations in these perovskites were removed, resulting in increased specific surface areas, better reducibility and greater activity. Incorporation of a small amount of Ce stabilized the structure and a perovskite phase persisted in La-deficient La1-xCexMnO3 mixed oxides after 12 ​h of acid dissolution. La0.95Ce0.05MnO3 after the acid treatment exhibited satisfactory catalytic activity, with T50 and T90 values of 365 and 459 ​°C, respectively, which was even comparable to that previously reported 1% Pd/Al2O3 catalysts. And it showed excellent long-term activity even in the presence of CO2 and H2O.

La-deficient La1-xCexMnO3 mixed oxides, obtained by selective dissolution in 1 ​M nitric acid, were employed in methane complete oxidation. The majority of the La cations in these perovskites were removed, resulting in increased specific surface areas, better reducibility and greater activity. Incorporation of a small amount of Ce stabilized the structure and a perovskite phase persisted in La-deficient La1-xCexMnO3 mixed oxides after 12 ​h of acid dissolution. La0.95Ce0.05MnO3 after the acid treatment exhibited satisfactory catalytic activity, with T50 and T90 values of 365 and 459 ​°C, respectively, which was even comparable to that previously reported 1% Pd/Al2O3 catalysts. And it showed excellent long-term activity even in the presence of CO2 and H2O.

Grouted-sleeve connections are widely used to connect prefabricated concrete members. The bond stress-slip behavior is an essential issue to be considered when assessing the performance of a grouted-sleeve connection loaded in tension. This paper presents an experimental investigation regarding the local and global bond stress-slip behavior of grouted-sleeve connections. Three parameters were investigated: the embedment length, construction eccentricity, and loading time after grouting, respectively. The specimens were subjected to a monotonic tensile load, and the slip between the bar and the grouted-sleeve was measured during the test. Moreover, to evaluate the confinement effect, the circumferential strain at the surface of the grouted-sleeve was measured. The results reveal that the maximum local bond stress increases with the age of the grout, whereas it decreases as the construction eccentricity of the bar increases. Moreover, the influence of the construction eccentricity is mitigated by a longer bonded length. The load-slip relationship is approximately linear for the specimen with an embedment length-to-bar diameter ratio equal to ten, loaded at the age of seven days. Based on the experimental results, an analytical model, including the local and global bond stress-slip relationship, is proposed to evaluate the maximum slip and to describe the strain distribution in the long specimens ( l b / d = 6, 10). The agreement among the experimental and calculated bond stress, the maximum slip and strain distribution at the surface of the sleeve demonstrates the validity of the proposed model.