The Hydrobios in Dongping Lake, Shandong Province, mainly includes phytoplankton, zooplankton, benthic animals, fishes and hydrophytic vascular plants. Nitrogen and phosphorus are the restrictive factors for the growt...The Hydrobios in Dongping Lake, Shandong Province, mainly includes phytoplankton, zooplankton, benthic animals, fishes and hydrophytic vascular plants. Nitrogen and phosphorus are the restrictive factors for the growth and propagation of hydrophyta, therefore the key to the prevention and control of eutrophication in lakes lies in the control of the contents of the two elements in the water. Artificial fishing of algae can reduce the concentrations of trophic substances such as nitrogen and phosphorus in the water bodies, and biological measures may decrease the contents of these trophic substances in the bottom sediments and the water bodies, thereby playing an active role in modifying the eutrophication of the lake.展开更多
Three-body interaction plays an important role in many-body physics,and quantum computer is efficient in simulating many-body interactions. We have experimentally demonstrated the general three-body interactions in a ...Three-body interaction plays an important role in many-body physics,and quantum computer is efficient in simulating many-body interactions. We have experimentally demonstrated the general three-body interactions in a three-qubit nuclear magnetic resonance ensemble quantum computer. Using a nuclear magnetic resonance computer we implemented general forms of three-body interactions including σ 1x σ z2 σ x3 and σ 1x σ z2 σ y3 . The results show good agreement between theory and experiment. We have also given a concise and practical formula for a general n-body interaction in terms of one-and two-body interactions.展开更多
The four-body interaction plays an important role in many-body systems, and it can exhibit interesting phase transition behaviors. In this letter, we report the experimental demonstration of a four-body interaction in...The four-body interaction plays an important role in many-body systems, and it can exhibit interesting phase transition behaviors. In this letter, we report the experimental demonstration of a four-body interaction in a four-qubit nuclear magnetic resonance quantum information processor. The strongly modulating pulse is used to implement spin selective excitation. The results show a good agreement between theory and experiment.展开更多
文摘The Hydrobios in Dongping Lake, Shandong Province, mainly includes phytoplankton, zooplankton, benthic animals, fishes and hydrophytic vascular plants. Nitrogen and phosphorus are the restrictive factors for the growth and propagation of hydrophyta, therefore the key to the prevention and control of eutrophication in lakes lies in the control of the contents of the two elements in the water. Artificial fishing of algae can reduce the concentrations of trophic substances such as nitrogen and phosphorus in the water bodies, and biological measures may decrease the contents of these trophic substances in the bottom sediments and the water bodies, thereby playing an active role in modifying the eutrophication of the lake.
基金the National Natural Science Foundation of China (Grant Nos. 10374010 and 10325521) the National Basic Research Program of China (Grant No. 2006CB921106)
文摘Three-body interaction plays an important role in many-body physics,and quantum computer is efficient in simulating many-body interactions. We have experimentally demonstrated the general three-body interactions in a three-qubit nuclear magnetic resonance ensemble quantum computer. Using a nuclear magnetic resonance computer we implemented general forms of three-body interactions including σ 1x σ z2 σ x3 and σ 1x σ z2 σ y3 . The results show good agreement between theory and experiment. We have also given a concise and practical formula for a general n-body interaction in terms of one-and two-body interactions.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 10775076, 10874098)National Basic Research Program of China (Grant Nos. 2006CB921106, 2009CB929402)Specialized Research Fund for the Doctoral Program of Education Ministry of China (Grant No. 20060003048)
文摘The four-body interaction plays an important role in many-body systems, and it can exhibit interesting phase transition behaviors. In this letter, we report the experimental demonstration of a four-body interaction in a four-qubit nuclear magnetic resonance quantum information processor. The strongly modulating pulse is used to implement spin selective excitation. The results show a good agreement between theory and experiment.