A probabilistic risk assessment procedure is developed which can predict risks of explosive blast damage to built infrastructure, and when combined with life-cycle cost analysis, the procedure can be used to optimise ...A probabilistic risk assessment procedure is developed which can predict risks of explosive blast damage to built infrastructure, and when combined with life-cycle cost analysis, the procedure can be used to optimise blast mitigation strategies. The paper focuses on window glazing since this is a load-capacity system which, when subjected to blast loading, has caused significant damage and injury to building occupants. Structural reliability techniques are used to derive blast reliability curves for annealed and toughened glazing subjected to explosive blast for a variety of threat scenarios. The probabilistic analyses include the uncertainties associated with blast modelling, glazing response and glazing failure criteria. Damage risks are calculated for an individual window and for windows in the facade of a multi-storey commercial building. The paper shows an illustrative example of how this information, when combined with risk-based decision-making criteria, can be used to optimise blast mitigation strategies.展开更多
A 2-D laminar flow model was established for CFD analysis of air-flow between louvered fins. Two louvered fins are studied based on commercial software FLUENT. Air-flow pressure drop characteristics are derived on the...A 2-D laminar flow model was established for CFD analysis of air-flow between louvered fins. Two louvered fins are studied based on commercial software FLUENT. Air-flow pressure drop characteristics are derived on the calculation of Reynolds number from 75.3 to 600. The numerical results are in good agreement with the experimental data when Reynolds is lower.展开更多
We have designed and synthesized NaGdF4:Nd^3+, Yb^3+, Tm^3+. magnetic nano- phosphors with combined dual-mode downconversion (DC) and upconversion (UC) photoluminescence upon 800 run excitation. Hexagonal-phas...We have designed and synthesized NaGdF4:Nd^3+, Yb^3+, Tm^3+. magnetic nano- phosphors with combined dual-mode downconversion (DC) and upconversion (UC) photoluminescence upon 800 run excitation. Hexagonal-phase NaGdF4:Nd^3+, Yb^3+, Tm^3+ nanocrystals (NCs) with an average size of 21 nm were synthesized using a solvothermal approach. Nd^3+, Yb^3+, Tm^3+ triple-doped NaGdF4 NCs exhibit a broad range of photoluminescence peaks covering a near infrared first/second window (860-900, 1,000, and 1,060 nm), and visible emission including blue (475 nm), green (520 and 542 nm) and yellow (587 nm) after excitation at 800 nm. A mechanism involving circulation of energy over Gd^3+ sublattices as bridge ions and final trapping by the initial activator ions (Nd^3+) has been proposed. Penetration depth studies indicate that NIR emission is easily detected even at a large tissue thickness of 10 mm. These paramagnetic nanophosphors demonstrate a large magnetization value of 1.88 emu/g at 20 kOe and longitudinal relaxivity value of 1.2537 mM-1.S-1 as a Tl-weighted magnetic resonance imaging contrast agent. These NaGdF4:Nd^3+, Yb^3+ Tm^3+ NCs are promising for applications in biological and magnetic resonance imaging.展开更多
文摘A probabilistic risk assessment procedure is developed which can predict risks of explosive blast damage to built infrastructure, and when combined with life-cycle cost analysis, the procedure can be used to optimise blast mitigation strategies. The paper focuses on window glazing since this is a load-capacity system which, when subjected to blast loading, has caused significant damage and injury to building occupants. Structural reliability techniques are used to derive blast reliability curves for annealed and toughened glazing subjected to explosive blast for a variety of threat scenarios. The probabilistic analyses include the uncertainties associated with blast modelling, glazing response and glazing failure criteria. Damage risks are calculated for an individual window and for windows in the facade of a multi-storey commercial building. The paper shows an illustrative example of how this information, when combined with risk-based decision-making criteria, can be used to optimise blast mitigation strategies.
文摘A 2-D laminar flow model was established for CFD analysis of air-flow between louvered fins. Two louvered fins are studied based on commercial software FLUENT. Air-flow pressure drop characteristics are derived on the calculation of Reynolds number from 75.3 to 600. The numerical results are in good agreement with the experimental data when Reynolds is lower.
文摘We have designed and synthesized NaGdF4:Nd^3+, Yb^3+, Tm^3+. magnetic nano- phosphors with combined dual-mode downconversion (DC) and upconversion (UC) photoluminescence upon 800 run excitation. Hexagonal-phase NaGdF4:Nd^3+, Yb^3+, Tm^3+ nanocrystals (NCs) with an average size of 21 nm were synthesized using a solvothermal approach. Nd^3+, Yb^3+, Tm^3+ triple-doped NaGdF4 NCs exhibit a broad range of photoluminescence peaks covering a near infrared first/second window (860-900, 1,000, and 1,060 nm), and visible emission including blue (475 nm), green (520 and 542 nm) and yellow (587 nm) after excitation at 800 nm. A mechanism involving circulation of energy over Gd^3+ sublattices as bridge ions and final trapping by the initial activator ions (Nd^3+) has been proposed. Penetration depth studies indicate that NIR emission is easily detected even at a large tissue thickness of 10 mm. These paramagnetic nanophosphors demonstrate a large magnetization value of 1.88 emu/g at 20 kOe and longitudinal relaxivity value of 1.2537 mM-1.S-1 as a Tl-weighted magnetic resonance imaging contrast agent. These NaGdF4:Nd^3+, Yb^3+ Tm^3+ NCs are promising for applications in biological and magnetic resonance imaging.