Most products have the potential to negatively impact the environment during all life-cycle stages.However,most environmental impact assessment methods focus on a single product life-cycle and on a specific life-cycle ...Most products have the potential to negatively impact the environment during all life-cycle stages.However,most environmental impact assessment methods focus on a single product life-cycle and on a specific life-cycle stage.Product design plays a significant role by determining traditional environmental impacts,such as embodied energy of materials,but also by influencing market adoption and production volumes.The main objective of this work is to develop a design optimization framework that estimates the environmental impact of design decisions(e.g.materials choice,etc.)across all life-cycle stages in consumer products.The methodology relies on quality function deployment(QFD),multi-attribute utility theory,non-linear mathematical programming,and life-cycle assess-ment tools to estimate the utility of the design options to the customer,the producer,and the environment.The proposed framework allows designers and other decision makers to select options that are environmentally sound and also aligned with the business objectives.展开更多
The thermoelectric properties of individual solution-phase synthesized p-type PbSe nanowires have been examined.The nanowires showed near degenerately doped charge carrier concentrations.Compared to the bulk,the PbSe ...The thermoelectric properties of individual solution-phase synthesized p-type PbSe nanowires have been examined.The nanowires showed near degenerately doped charge carrier concentrations.Compared to the bulk,the PbSe nanowires exhibited a similar Seebeck coefficient and a significant reduction in thermal conductivity in the temperature range 20 K to 300 K.Thermal annealing of the PbSe nanowires allowed their thermoelectric properties to be controllably tuned by increasing their carrier concentration or hole mobility.After optimal annealing,single PbSe nanowires exhibited a thermoelectric figure of merit(ZT)of 0.12 at room temperature.展开更多
文摘Most products have the potential to negatively impact the environment during all life-cycle stages.However,most environmental impact assessment methods focus on a single product life-cycle and on a specific life-cycle stage.Product design plays a significant role by determining traditional environmental impacts,such as embodied energy of materials,but also by influencing market adoption and production volumes.The main objective of this work is to develop a design optimization framework that estimates the environmental impact of design decisions(e.g.materials choice,etc.)across all life-cycle stages in consumer products.The methodology relies on quality function deployment(QFD),multi-attribute utility theory,non-linear mathematical programming,and life-cycle assess-ment tools to estimate the utility of the design options to the customer,the producer,and the environment.The proposed framework allows designers and other decision makers to select options that are environmentally sound and also aligned with the business objectives.
文摘The thermoelectric properties of individual solution-phase synthesized p-type PbSe nanowires have been examined.The nanowires showed near degenerately doped charge carrier concentrations.Compared to the bulk,the PbSe nanowires exhibited a similar Seebeck coefficient and a significant reduction in thermal conductivity in the temperature range 20 K to 300 K.Thermal annealing of the PbSe nanowires allowed their thermoelectric properties to be controllably tuned by increasing their carrier concentration or hole mobility.After optimal annealing,single PbSe nanowires exhibited a thermoelectric figure of merit(ZT)of 0.12 at room temperature.
