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Multifunctional magneto-plasmonic nanoparticles with magnetic hyperthermia and photothermal therapy could kill cancer cells efficiently. Herein, carbon-encapsulated Au/Fe3O4 (Au/Fe3O4@C) was fabricated using an enclosed flame spray pyrolysis. The nanostructures, including an Fe3O4 core (51.9–55.2 nm) with a decreasing carbon shell thickness and an Au core (4.68–8.75 nm) coated with 2–4 graphite layers, were tailored by tuning the C2H4 content in the reacting gas mixture. Saturation magnetization (33.7–48.2 emu/g) and optical absorption were determined. The carbon shell facilitated the dispersion of Au/Fe3O4 and restrained their laser-induced and magnetic field-induced coalescence and growth. Au/Fe3O4@C exhibited excellent magnetic resonance imaging capability (91.4 mM−1 s−1) and photothermal performance (65.4°C for 0.8 mg/mL Au/Fe3O4@C at a power density of 1.0 W/cm2 after 300 s near-IR laser irradiation (808 nm)). Moreover, the combined application of photothermal and magnetic-heating properties reduced the required intensity of both laser and magnetic field compared to the intensity of separate situations. Our work provides a unique, intriguing approach to preparing multicomponent core/shell nanoaggregates that are promising candidates for esophageal cancer cell therapy.

The Jianghuai area is an “important” region not only for its local pollutant accumulation but the belt for pollutant transportation between North China and the Yangtze River Delta during the winter half of the year (often from October to next February). In this study, a movable boundary layer conceptual model for the Jianghuai area in the winter half of the year is established based on the analyses of characteristics of atmospheric circulations and boundary layer dynamic conditions. This conceptual model can well explain the causes of air quality change and frequent fog-haze episodes. Variations of the intensity and range of the cold and warm fronts in the Jianghuai area in the winter half of the year lead to form a movable boundary in this area. When the southerly wind is strong, or affected by strong cold air mass, the air quality in the Jianghuai area may be excellent with a low air pollution index; Two atmospheric circulations provide favorable conditions for the fog-haze formation and maintenance in Jianghuai area: 1) When the shallow weak cold air mass is below the deep moist warm air mass, a stable temperature inversion occurs. The pollutants are transported to the Jianghuai area by the weak cold air mass, and local emissions also accumulate. As a result, a severe air pollution episode appears. 2) When the northerly cold air mass is as intense as the southerly moist warm air mass, the pollutants transported from North China as well as local emissions will continuously accumulate in the study area, which may lead to more severe air pollution. This conceptual model can help us analyze atmospheric diffusion capacity, and benefit the forecast and early warning of airflow stagnation area and fog-haze episode.