Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead p...Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead pollution on children around the industry park, blood samples of neighboring children were collected and analyzed in laboratory. The results showed that the involved children have suffered serious harms from Pb pollution. Almost 75% of the children's blood lead levels (BLLs) exceeded the limit of normal blood lead. Worse still, 26.17% of them were at the level of Moderate lead poisoning. The group aged 0-7 showed more susceptibility to Pb than that aged 8-14. Only 19.05% of the children aged 0-7 were at the level of normal blood lead, compared with 45.45% in the group aged 8-14. There was no significant difference between the values of blood lead concentration for male and female or among different age groups. Some approaches, which include controlling the Pb pollution from the industry park and safeguarding the residents, esp. the children were suggested.展开更多
In this work, a novel morphing machining strategy (MMS) is proposed. In the method, the workpiece is progressively carved out from the stock. Pitfalls in conventional iso-height strategy, such as sharp edges and une...In this work, a novel morphing machining strategy (MMS) is proposed. In the method, the workpiece is progressively carved out from the stock. Pitfalls in conventional iso-height strategy, such as sharp edges and unevenly distributed left-over materials, are overcome. Moreover, to calculate different levels in the MMS, an energy-based morphing algorithm is proposed. Finally, the proposed strategy is employed in the machining of artificial bone represented by a T-spline surface. The excellent properties of T-spline, such as expressing complex shapes with a single surface, have been well adopted to artificial bone fabri- cation. Computer simulation and the actual machining of the middle finger bone show the feasibility of the proposed strategy.展开更多
文摘Lead is an important toxic heavy metal among environment pollution. Some industrial parks were founded in 2005 including non-ferrous metal processing and smelting plants. In order to identify the consequence of lead pollution on children around the industry park, blood samples of neighboring children were collected and analyzed in laboratory. The results showed that the involved children have suffered serious harms from Pb pollution. Almost 75% of the children's blood lead levels (BLLs) exceeded the limit of normal blood lead. Worse still, 26.17% of them were at the level of Moderate lead poisoning. The group aged 0-7 showed more susceptibility to Pb than that aged 8-14. Only 19.05% of the children aged 0-7 were at the level of normal blood lead, compared with 45.45% in the group aged 8-14. There was no significant difference between the values of blood lead concentration for male and female or among different age groups. Some approaches, which include controlling the Pb pollution from the industry park and safeguarding the residents, esp. the children were suggested.
基金Project supported by the Science Fund for Creative Research Groups of National Natural Science Foundation of China (No. 51221004), and the National Natural Science Foundation of Chi:na (Nos. 51175461 and 51105335)
文摘In this work, a novel morphing machining strategy (MMS) is proposed. In the method, the workpiece is progressively carved out from the stock. Pitfalls in conventional iso-height strategy, such as sharp edges and unevenly distributed left-over materials, are overcome. Moreover, to calculate different levels in the MMS, an energy-based morphing algorithm is proposed. Finally, the proposed strategy is employed in the machining of artificial bone represented by a T-spline surface. The excellent properties of T-spline, such as expressing complex shapes with a single surface, have been well adopted to artificial bone fabri- cation. Computer simulation and the actual machining of the middle finger bone show the feasibility of the proposed strategy.