Al2O3-coated FeCo nanocapsules were synthesized by the arc-discharge method and three-dimensional wire-like macro-aggregates were self-assembled simultaneously by nanocapsules. The electromagnetic (EM) parameters (i.e. the relative permeability and permittivity) were measured at 2–18 GHz. As a consequence of the surface- and shape-anisotropy energy of the nanocapsules, a natural resonance at 6 GHz is dominant in the microwave absorption properties. A reflection loss (RL) exceeding −20 dB was obtained in the frequency range 4.2–18 GHz for absorber thicknesses of 1.3–6 mm. An optimal RL of −51 dB was found at 10.2 GHz for an absorber thickness of 2 mm. As a result, the Al2O3-coated FeCo nanocapsules show good prospects of being applied in EM wave absorptive devices.

A large magnetoresistance (MR) is observed in a double helical CoMnSi compound over the entire temperature region from 5 K to the maximum measuring temperature of 380 K, with the largest MR ratio of −18.3% at 245 K and the smallest MR ratio of −5.5% at 85 K at 5 T. This phenomenon is ascribed to two different mechanisms in different temperature regions. The suppressed spin fluctuations of the double helical structure are responsible for the MR below 110 K. However, in consideration of the natural multilayer superstructure of CoMnSi, the larger MR above 110 K is ascribed to the decrease in K-space restrictions when the change in magnetic structure from double helical order to fan order occurs.

Abstract. Mollusk samples such as bivalves and gastropods were collected from eight sampling sites along Bohai Sea coastline from northeastern China. The samples were analyzed for polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC-HRMS) to elucidate bioaccumulation of persistent organic pollutants in benthon. Residue levels of SPCBs and SPCDD/Fs were in the ranges of 66.1 to 583.6 ng/g and 0.9 to 15317 pg/g on a lipid-weight basis, respectively, The pollution source was identified using principal component analysis (PCA) in some coastal areas. It indicated that the typical pollution sources were characterized by PCB 3 , which was one Chinese technical product of PCBs. PCA also revealed the similarity patterns of PCBs between identical species collected from the different sites. The higher gastropod PCB concentrations were related to a former capacitor factory and the paint factories in some coastal areas, but this was not the case with the bivalves. The results of this study suggest that some gastropod species may be a potential bioindicator or ''sentinel'' organism for marine PCBs monitoring.

A previous modeling study of the lake-floodplain system of Poyang Lake (China) revealed complex hysteretic relationships between stage, storage volume and surface area. However, only hypothetical causal factors were presented, and the reasons for the occurrence of both clockwise and counterclockwise hysteretic functions were unclear. The current study aims to address this by exploring further Poyang Lake's hysteretic behavior, including consideration of stage-flow relationships. Remotely sensed imagery is used to validate the water surface areas produced by hydrodynamic modeling. Stage-area relationships obtained using the two methods are in strong agreement. The new results reveal a three-phase hydrological regime in stage-flow relationships, which assists in developing improved physical interpretation of hysteretic stage-area relationships for the lake-floodplain system. For stage-area relationships, clockwise hysteresis is the result of classic floodplain hysteretic processes (e.g., restricted drainage of the floodplain during recession), whereas counterclockwise hysteresis derives from the river hysteresis effect (i.e., caused by backwater effects). The river hysteresis effect is enhanced by the time lag between the peaks of catchment inflow and Yangtze discharge (i.e., the so-called Yangtze River blocking effect). The time lag also leads to clockwise hysteresis in the relationship between Yangtze River discharge and lake stage. Thus, factors leading to hysteresis in other rivers, lakes and floodplains act in combination within Poyang Lake to create spatial variability in hydrological hysteresis. These effects dominate at different times, in different parts of the lake, and during different phases of the lake's water level fluctuations, creating the unique hysteretic hydrological behavior of Poyang Lake.

A giant magnetoresistance (GMR) is observed in the Mn2−xZnxSb (x < 0.3) system, with the largest MR ratio of −37.6% in a field of 5 T at 120 K for the Mn1.9Zn0.1Sb compound. Different from other Mn2Sb-based compounds, the GMR in Mn2−xZnxSb is closely correlated with a field-induced transition from a weak ferrimagnetic (WFI) state to a ferrimagnetic (FI) state. It is understood that the influences of both super-zone gap and spin-dependent scattering are responsible for GMR in the present system. Magnetic hysteresis and phase coexistence of the WFI and the FI phases suggest that this WFI–FI transition is of first order. The different mechanisms responsible for butterfly loops of magnetization/resistivity curves in different magnetic states are discussed.

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Lakes play a crucial role in retaining water and altering biogeochemical processes on floodplains. Existing strategies and algorithms for estimation of water storage are insufficient for dynamic floodplain lakes due to the scarcity of available observations. Combining a time series of open water area with a fine spatial-temporal resolution by integrating Landsat and MODIS observations of Poyang Lake (China) with digital elevation models, and limited gauge data, generated water storage estimates as a function of surface hydrological connectivity. Despite possessing a relatively small portion of Poyang Lake's water volume, the floodplain lakes occupy a large part of the surface water area, especially in the low water period. Floodplain lakes, in particular, those distributed in the upper delta contribute to relieving drought conditions in Poyang Lake.

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