Suspended particles in the air are pollutants formed by diverse materials and sizes. As determined in multiple studies, particulate matter equal to or less than 2.5 μrn also called breathable fraction is the one that...Suspended particles in the air are pollutants formed by diverse materials and sizes. As determined in multiple studies, particulate matter equal to or less than 2.5 μrn also called breathable fraction is the one that penetrates the inferior respiratory system. The present study shows the results of a sampling campaign of particulate matter PM25 through 12 months at 3 sites: C33 (Clinic 33), CIM (CIMAV) and A VA (Avalos) at Chihuahua, Mexico. The aim of this study was to determine the temporary concentrations of PM25, the concentration of metallic elements: Al, As, Co, Cu, Sb, Se, Fe, Mg, Mn, Ni, Pb and Zn, as well as their possible sources. The three sites had the same trend in the time, where in autumn and winter the higher concentrations were found. The yearly averages on sites C33, CIM, and AVA were 9.91, 12.74 and 21.67 μg·m^-3, respectively, finding that AVA site overpasses the standard of 15 μg·m^-3. The application of factor analysis to the data allowed to identify four source categories: crustal, related with Al-Co-Fe-Mg-Mn, vehicular, related with: As-Cu-Sb-Se; mixed, related with: As-Cu-Sb-Se-Pb-Zn and industrial related with Ni-Pb.展开更多
Exploiting the optical excitation selection rules in graphene quantum dots, we investigate theoretically the entanglement generation process and entanglement concentration process of valley qubits. Our protocol shows ...Exploiting the optical excitation selection rules in graphene quantum dots, we investigate theoretically the entanglement generation process and entanglement concentration process of valley qubits. Our protocol shows that the graphene-based quantum dots can be distributed in a maximally entangled state through the interaction with single photons. In our proposed scheme, the setups are simplified as only single-photon detection is required. This provides a fast, all-optical manipulation of on-chip qubits,which gives an effective way for quantum information processing in graphene-based solid qubits.展开更多
文摘Suspended particles in the air are pollutants formed by diverse materials and sizes. As determined in multiple studies, particulate matter equal to or less than 2.5 μrn also called breathable fraction is the one that penetrates the inferior respiratory system. The present study shows the results of a sampling campaign of particulate matter PM25 through 12 months at 3 sites: C33 (Clinic 33), CIM (CIMAV) and A VA (Avalos) at Chihuahua, Mexico. The aim of this study was to determine the temporary concentrations of PM25, the concentration of metallic elements: Al, As, Co, Cu, Sb, Se, Fe, Mg, Mn, Ni, Pb and Zn, as well as their possible sources. The three sites had the same trend in the time, where in autumn and winter the higher concentrations were found. The yearly averages on sites C33, CIM, and AVA were 9.91, 12.74 and 21.67 μg·m^-3, respectively, finding that AVA site overpasses the standard of 15 μg·m^-3. The application of factor analysis to the data allowed to identify four source categories: crustal, related with Al-Co-Fe-Mg-Mn, vehicular, related with: As-Cu-Sb-Se; mixed, related with: As-Cu-Sb-Se-Pb-Zn and industrial related with Ni-Pb.
基金supported by the National Natural Science Foundation of China(1140403161205117+3 种基金and61471050)Beijing Higher Education Young Elite Teacher Project(YETP0456)the Fundamental Research Funds for the Central Universities(2014RC0903)the State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications)
文摘Exploiting the optical excitation selection rules in graphene quantum dots, we investigate theoretically the entanglement generation process and entanglement concentration process of valley qubits. Our protocol shows that the graphene-based quantum dots can be distributed in a maximally entangled state through the interaction with single photons. In our proposed scheme, the setups are simplified as only single-photon detection is required. This provides a fast, all-optical manipulation of on-chip qubits,which gives an effective way for quantum information processing in graphene-based solid qubits.