Under the guidance of strain tolerance, a new combination method for crude oil-degrading bacterial consortium was studied. Firstly, more than 50 efficient crude oil-degrading and biosurfactant producing bacteria were ...Under the guidance of strain tolerance, a new combination method for crude oil-degrading bacterial consortium was studied. Firstly, more than 50 efficient crude oil-degrading and biosurfactant producing bacteria were isolated from petroleum-contaminated soil and water in Tianjin Binhai New Area Oil field, China. Twenty-four of them were selected for further study. These strains were identified as belonging Pseudornonas aeruginosa, Bacillus subtilis, Brevibacillus brevis, Achrornobacter sp., Acinetobacter venetianus, Lysinibacillus rnacroides, Klebsiella oxytoca, Stenotrophornonas rhizophila, Rhodococcus sp. and Bacillus thuringiensis. A shake-flask degradation test revealed that 12 of these strains could degrade over 50% of 1% crude oil concentration in 7 d. Of these, 8 strains were able to produce biosurfactants. Furthermore, environmental tolerance experiments indicated that the majority of the strains had the ability to adapt to extreme environments including high temperatures, alkaline en- vironments and high salinity environments. A mixed bacterial agent comprising the strains WB2, W2, W3 and HA was developed based on the environmental tolerance tests and subjected to the pilot-scale degradation test indicating that this bacterial agent could degrade 85.2% of 0.8% crude oil concentration in 60 d. Our results suggest that the application of this mixed agent could remediate crude oil polluted soils in saline and alkaline environments.展开更多
Given an m × n mesh-connected VLSI array with some faulty elements, the reconfiguration problem is to find a maximum-sized fault-free sub-array under the row and column rerouting scheme. This problem has already ...Given an m × n mesh-connected VLSI array with some faulty elements, the reconfiguration problem is to find a maximum-sized fault-free sub-array under the row and column rerouting scheme. This problem has already been shown to be NP-complete. In this paper, new techniques are proposed, based on heuristic strategy, to minimize the number of switches required for the power efficient sub-array. Our algorithm shows that notable improvements in the reduction of the number of long interconnects could be realized in linear time and without sacrificing on the size of the sub-array. Simulations based on several random and clustered fault scenarios clearly reveal the superiority of the proposed techniques.展开更多
基金Supported by the National Basic Research Program of China(“973”Program:2014CB745100)the National Natural Science Foundation of China(21576197)+2 种基金Tianjin Research Program of Application Foundation and Advanced Technology(14JCQNJC06700)the Major Research Plan of Tianjin(16YFXTSF00460)Tianjin Penglai 19-3 Oil Spill Accident Compensation Project(19-3BC2014-03)
文摘Under the guidance of strain tolerance, a new combination method for crude oil-degrading bacterial consortium was studied. Firstly, more than 50 efficient crude oil-degrading and biosurfactant producing bacteria were isolated from petroleum-contaminated soil and water in Tianjin Binhai New Area Oil field, China. Twenty-four of them were selected for further study. These strains were identified as belonging Pseudornonas aeruginosa, Bacillus subtilis, Brevibacillus brevis, Achrornobacter sp., Acinetobacter venetianus, Lysinibacillus rnacroides, Klebsiella oxytoca, Stenotrophornonas rhizophila, Rhodococcus sp. and Bacillus thuringiensis. A shake-flask degradation test revealed that 12 of these strains could degrade over 50% of 1% crude oil concentration in 7 d. Of these, 8 strains were able to produce biosurfactants. Furthermore, environmental tolerance experiments indicated that the majority of the strains had the ability to adapt to extreme environments including high temperatures, alkaline en- vironments and high salinity environments. A mixed bacterial agent comprising the strains WB2, W2, W3 and HA was developed based on the environmental tolerance tests and subjected to the pilot-scale degradation test indicating that this bacterial agent could degrade 85.2% of 0.8% crude oil concentration in 60 d. Our results suggest that the application of this mixed agent could remediate crude oil polluted soils in saline and alkaline environments.
文摘Given an m × n mesh-connected VLSI array with some faulty elements, the reconfiguration problem is to find a maximum-sized fault-free sub-array under the row and column rerouting scheme. This problem has already been shown to be NP-complete. In this paper, new techniques are proposed, based on heuristic strategy, to minimize the number of switches required for the power efficient sub-array. Our algorithm shows that notable improvements in the reduction of the number of long interconnects could be realized in linear time and without sacrificing on the size of the sub-array. Simulations based on several random and clustered fault scenarios clearly reveal the superiority of the proposed techniques.
