The seismic behaviors of an integral concreting frame, a light steel storey-adding frame and a storeyadding frame strengthened with carbon fiber reinforced polymer(CFRP)were investigated under low-cycle and repeated l...The seismic behaviors of an integral concreting frame, a light steel storey-adding frame and a storeyadding frame strengthened with carbon fiber reinforced polymer(CFRP)were investigated under low-cycle and repeated load(scale 1∶3). The failure characteristics, hysteretic behavior, rigidity degeneracy, deflection ductility and energy-dissipation capacity of the three specimens were compared. The test results reveal that chemicallybonded rebar technique can meet the requirements of storey-adding engineering. The carrying capacity, the deflection ductility, the energy-dissipating capacity and seismic performance of the light steel storey-adding frame are higher than those of the integral concreting frame, and they are the highest in the storey-adding frame strengthened with CFRP.展开更多
Novel carbon nanohybrids based on unmodified metallofullerenes have been successfully fabricated for use as a new magnetic resonance imaging （MRI） contrast agent. The nanohybrids showed higher R1 relaxivity and bett...Novel carbon nanohybrids based on unmodified metallofullerenes have been successfully fabricated for use as a new magnetic resonance imaging （MRI） contrast agent. The nanohybrids showed higher R1 relaxivity and better brightening effect than Gd@C82（OH）x, in Tl-weighted MR images in vivo. This is a result of the proton relaxivity from the original gadofullerenes, which retained a perfect carbon cage structure and so might completely avoid the release of Gd^3＋ ions. A ＂secondary spin-electron transfer＂ relaxation mechanism was proposed to explain how the encaged Gd^3＋ ions of carbon nanohybrids interact with the surrounding water molecules. This approach opens new opportunities for developing highly efficient and low toxicity MRI contrast agents.展开更多
基金Supported by the National Natural Science Foundation of China(No.51379142)
文摘The seismic behaviors of an integral concreting frame, a light steel storey-adding frame and a storeyadding frame strengthened with carbon fiber reinforced polymer(CFRP)were investigated under low-cycle and repeated load(scale 1∶3). The failure characteristics, hysteretic behavior, rigidity degeneracy, deflection ductility and energy-dissipation capacity of the three specimens were compared. The test results reveal that chemicallybonded rebar technique can meet the requirements of storey-adding engineering. The carrying capacity, the deflection ductility, the energy-dissipating capacity and seismic performance of the light steel storey-adding frame are higher than those of the integral concreting frame, and they are the highest in the storey-adding frame strengthened with CFRP.
文摘Novel carbon nanohybrids based on unmodified metallofullerenes have been successfully fabricated for use as a new magnetic resonance imaging （MRI） contrast agent. The nanohybrids showed higher R1 relaxivity and better brightening effect than Gd@C82（OH）x, in Tl-weighted MR images in vivo. This is a result of the proton relaxivity from the original gadofullerenes, which retained a perfect carbon cage structure and so might completely avoid the release of Gd^3＋ ions. A ＂secondary spin-electron transfer＂ relaxation mechanism was proposed to explain how the encaged Gd^3＋ ions of carbon nanohybrids interact with the surrounding water molecules. This approach opens new opportunities for developing highly efficient and low toxicity MRI contrast agents.
