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It is important to quickly strengthen and repair earthquake-damaged buildings to restore the normal life after earthquake. Therefore, it is necessary to study the seismic performance of widely-used assembled buildings repaired with different approaches. In this paper, two different methods are designed to repair seismically damaged shear walls assembled with grouted sleeves. Based on different damage scenarios, the first method uses high-strength grout to replace damaged concrete, and the second method uses grout jacketing with reinforcement implantation and reinforcing mesh to enhance the damaged cross-section. The repaired walls are compared with the original walls on the damage mode, bearing capacity, ductility, energy dissipation capacity, and stiffness degradation. The test results verify that both repair methods can restore the load-bearing capacity of the assembled shear walls. Further, the seismic performance of the two repaired seismic-damaged shear walls with different axial pressure ratios is analyzed using finite element analysis. The seismic loss indices of the original assembled and the repaired shear walls are calculated using the Park-Ang two-parameter seismic damage model based on the results of the experimental studies and the finite element analysis.

Cathode material Li [Li0.2Ni0.2Co0.08Mn0.52−xCux]O2 (x = 0, 0.01, 0.03, 0.05, 0.07) has been synthesized via carbonate coprecipitation method and modified by Cu2+ which was introduced at different stages. The crystal structure features, morphology, and electrochemical properties of the powders are studied in detail using X-ray diffraction spectroscopy, scanning electron microscopy, EDS spectroscopy, and electrochemical measurements. The experimental results show that the electrochemical properties of Li [Li0.2Ni0.2Co0.08Mn0.52−xCux]O2 (x = 0, 0.01, 0.03, 0.05, 0.07) oxides are improved. This is because an appropriate amount of Cu2+ doping increases the lattice spacing of the layered material, reduces the agglomeration of the particles, and improves the uniformity of the particles. Especially in the coprecipitation stage, Cu2+ was introduced and x = 3% showed better rate and cycle performance. The specific discharge capacity at 1C and 2C was 197.28 mAhg−1 and 124.92 mAhg−1, respectively, and cycle returned to 0.1C capacity after 45 cycles, the discharge specific capacity is still up to 261.5 mAhg−1. [ABSTRACT FROM AUTHOR]

In this paper, LiMn1−xMgxPO4·Li3V2(PO4)3/C (x = 0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.10) and LiMnPO4·Li3V2−yAly(PO4)3/C (y = 0.01, 0.02, 0.03, 0.05, 0.07, 0.10) composite cathode materials for lithium-ion batteries were successfully synthesized by a simple sol-gel method and modified by Mg2+ doped and Al3+ doped. The effects of Mg2+ and Al3+ doping on the microstructure and electrochemical properties of LiMnPO4·Li3V2(PO4)3/C were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), EDAS energy spectrum analysis (EDS), constant current charge/discharge electrical test, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). The analysis shows that the electrochemical properties of samples have been greatly improved. The results show that when x = 0.06 and y = 0.02, the material has the best electrochemical performance. Under the voltage range of 2.5–4.5 V, the initial discharge specific capacity at 0.1 C (1 C = 143 mAh g−1) is as high as 148.2 mAh g−1 and 134.4 mAh g−1, respectively. [ABSTRACT FROM AUTHOR]

The samples of xLi3V2(PO4)3·yLiFe0.8Mn0.2PO4/C (x:y = 1:0, 3:1, 1:1, 1:2, 0:1) are facilely prepared via a ball milling-assisted two-step sintering route. According to the results of Rietveld refinement, the xLi3V2(PO4)3·yLiFe0.8Mn0.2PO4/C (x, y ≠ 0) composites are composed of orthorhombic LiFe0.8Mn0.2PO4 and monoclinic L3V2(PO4)3. Electrochemical tests show that the faster reaction kinetics improve the electrochemical properties of the xLi3V2(PO4)3·yLiFe0.8Mn0.2PO4/C (x, y ≠ 0) composites, in which all multiphase composites release more than capacity of 100 mAh g−1 at 2C at the potential range of 2.5-4.5 V. In particular, the diffusion coefficient of lithium ion is in the magnitude of 10−7 to 10−9 cm2 s−1; Li3V2(PO4)3·2LiFe0.8Mn0.2PO4/C shows the highest specific capacity at the rate range of 0.1-2C and exhibits excellent long-term rate performance with capacity retention of 93.4% (relative to the initial discharge capacity) after 280 cycles at the rate of 5C. [ABSTRACT FROM AUTHOR]

Populus deltoides is a fast-growing, large tree and one of the largest North American hardwood trees. In this study, the complete chloroplast (cp) genome sequence of P. deltoides is characterized. The whole cp genome was assembled to 156,867 bp, including a large single copy (LSC) region of 85,534 bp, a small single copy (SSC) region of 16,513 bp and a pair of inverted repeats (IRs) region of 27,410 bp. The base content of the P. deltoides cp genome is A (32.0%), T (31.3%), C (18.0%), and G (18.7%), and AT bases occupy a large proportion of the cp genome. The neighbor-joining phylogenetic analysis with 20 cp genomes from the Salicaceae family showed that P. deltoides is sister to Populus davidiana. These will provide for the evolutionary and biological studies in Salicaceae family. [ABSTRACT FROM AUTHOR]