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Sea ice export through the Baffin Bay plays a vital role in modulating the sea ice cover variability in the Labrador Sea. In this study, satellite-derived sea ice products are used to obtain the sea ice area flux (SIAF) through the three passages in the Baffin Bay (referred to as A, B, and C for the north, middle, and south passages, respectively). The spatial variability of the monthly sea ice drift in the Baffin Bay is presented. The interannual variability and trends in SIAF via the three passages are outlined. The connection to several large-scale atmospheric circulation modes is assessed. Over the period of 1988–2015, the average annual (October to the following September) SIAF amounts to 555×103 km2, 642×103 km2, and 551×103 km2 through Passages A, B, and C, respectively. These quantities are less than that observed through the Fram Strait (FS, 707×103 km2) of the corresponding period. The positive trends in annual SIAF, on the order of 53.1×103 km2/(10 a) and 43.2×103 km2/(10 a) (significant at the 95% confidence level), are identified at Passages A and B, respectively. The trend of the south passage (C), however, is slightly negative (−13.3×103 km2/(10 a), not statistically significant). The positive trends in annual SIAF through the Passages A and B are primarily attributable to the significant increases after 2000. The connection between the Baffin Bay sea ice export and the North Atlantic Oscillation is not significant over the studied period. By contrast, the association with the cross-gate sea level pressure difference is robust in the Baffin Bay (R equals 0.69 to 0.71, depending on the passages considered), but relatively weaker than that over FS (R=0.74). [ABSTRACT FROM AUTHOR]

Two different morphologies of ZnO (lotus-shaped, rod-shaped) and ZnO/PVDF composite materials were prepared. The morphologies of ZnO and composite materials were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Fourier transform infrared spectroscopy (FT-IR), thermal gravimetry (TG), and X-ray diffraction (XRD) were also used to characterize the chemical structures and phase composites of ZnO and ZnO/PVDF composite materials. Breakdown voltage, dielectric constant and dielectric loss of ZnO/PVDF composite materials were also tested. Microstructure analysis showed that ZnO nanoparticles dispersed uniformly in the matrix. And the dielectric constant expresses a significantly improvement while the dielectric loss and breakdown voltage expresses no significant change. Moreover, dielectric constant keeps an improvement tendency with increasing content of ZnO. [ABSTRACT FROM AUTHOR]

By combing satellite-derived ice motion and concentration with ice thickness fields from a popular model PIOMAS we obtain the estimates of ice volume flux passing the Fram Strait over the 1979-2012 period. Since current satellite and field observations for sea ice thickness are limited in time and space, the use of PIOMAS is expected to fill the gap by providing temporally continued ice thickness fields. Calculated monthly volume flux exhibits a prominent annual cycle with the peak record in March (roughly 145 km/month) and the trough in August (10 km/month). Annual ice volume flux (1 132 km) is primarily attributable to winter (October through May) outflow (approximately 92%). Uncertainty in annual ice volume export is estimated to be 55 km (or 5.7%). Our results also verified the extremely large volume flux appearing between late 1980s and mid- 1990s. Nevertheless, no clear trend was found in our volume flux results. Ice motion is the primary factor in the determination of behavior of volume flux. Ice thickness presented a general decline trend may partly enhance or weaken the volume flux trend. Ice concentration exerted the least influences on modulating trends and variability in volume flux. Moreover, the linkage between winter ice volume flux and three established Arctic atmospheric schemes were examined. Compared to NAO, the DA and EOF3 mechanism explains a larger part of variations of ice volume flux across the strait. [ABSTRACT FROM AUTHOR]

The culture of suspended kelp, such as Laminaria japonica Aresch, has arisen in nearshore areas for approximately 30 years since the 1980s. This long-term activity has significant impact on the regional hydrodynamic and sedimentary environments. In this study the impact was investigated, based on synchronized multi-station data from continuous observations made within and around the culture area. In total, three current velocity profiles were identified inside and on the landward side of the culture area. Based on the current velocity profiles we calculated the boundary layer parameters, the fluxes of erosion/deposition, and the rate of sediment transport in different times at each observation site. Comparison between culture and non-culture periods showed that the presence of suspended kelp caused the reduction in the average flow velocity by approximately 49.5%, the bottom friction velocity by 24.8%, the seabed roughness length by 62.7%, and the shear stress and the flux of resuspended sediment by approximately 50%. From analyses in combination with the corresponding vertical variation of the suspended sediment distribution, it is revealed that the lifted sediments by resuspension is mixed with the upper suspended material, which will modify the regional distribution of suspended sediment. These changes in flow structure and sediment movement will accelerate seabed siltation, which corresponds to the changes in seabed erosion/deposition. However, under the influences of the seasonal changes in kelp growth the magnitude of change with the seabed siltation was not obvious inside the culture area, but a fundamental change was apparent around the culture area. [ABSTRACT FROM AUTHOR]

A novel core-shell structure Ag@AlO nano-particles were synthesized and doped into polyimide as conductive fillers to prepare the composite films with high dielectric properties and low dielectric loss. The morphology and structures of the Ag@AlO nano-particles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-visible spectroscopy. All the results proved that the Ag@AlO nano-particles had a typical core-shell structure, for the Ag particles were coated by AlO shell and the average sizes of Ag@AlO particles were between 30 to 150 nm. The as-prepared Ag@AlO nanoparticles were doped into the polyimide with different mass fractions to fabricate the Ag@AlO/PI composite films via in-situ polymerization process. SEM analysis of composite films showed that the Ag@AlO nanoparticles homogeneously dispersed in polyimide matrix with nanoscale. As dielectric materials for electronic packaging systems, the Ag@AlO/PI composites exhibited appropriate mechanical properties and enhanced dielectric properties, including greatly enhanced dielectric constant and just a slight increase in dielectric loss. These improvements were attributed to the core-shell structure of fillers and their fine dispersion in the PI matrix. [ABSTRACT FROM AUTHOR]

Settling particulate matter (SPM) is widely used to describe the sedimentary environment. We have investigated here the SPM collected with a time-series sediment trap in the Heini Bay, Weihai, Shandong Peninsula, China, during the super typhoon Muifa (August 2011, maximum wind speed 55 m/s). Meteorological and hydrological parameters were measured for 18 days. By analyzing the particle flux, grain size, and loss-on-ignition (organic matter content) of SPM we found dramatic changes in these parameters, induced by typhoon Muifa for about 6 days. With the arrival of typhoon, the daily SPM fluxes increased sharply to the maximum at 76.4 g/(m·d) on the first day and this increase is about 9 times of the normal value, and after 6 days the SPM decreased to the normal value gradually. Other parameters, such as grain size of SPM and organic matter also experienced similar changes. Using these SPM parameters, we divided the settling progress by cluster analysis into three phases: strong (for 3 days), weak (for 3 days), and zero typhoon impact. [ABSTRACT FROM AUTHOR]

A modified algorithm taking into account the first year (FY) and multiyear (MY) ice densities is used to derive a sea ice thickness from freeboard measurements acquired by satellite altimetry ICESat (2003-2008). Estimates agree with various independent in situ measurements within 0.21 m. Both the fall and winter campaigns see a dramatic extent retreat of thicker MY ice that survives at least one summer melting season. There were strong seasonal and interannual variabilities with regard to the mean thickness. Seasonal increases of 0.53 m for FY the ice and 0.29 m for the MY ice between the autumn and the winter ICESat campaigns, roughly 4-5 month separation, were found. Interannually, the significant MY ice thickness declines over the consecutive four ICESat winter campaigns (2005-2008) leads to a pronounced thickness drop of 0.8 m in MY sea ice zones. No clear trend was identified from the averaged thickness of thinner, FY ice that emerges in autumn and winter and melts in summer. Uncertainty estimates for our calculated thickness, caused by the standard deviations of multiple input parameters including freeboard, ice density, snow density, snow depth, show large errors more than 0.5 m in thicker MY ice zones and relatively small standard deviations under 0.5 m elsewhere. Moreover, a sensitivity analysis is implemented to determine the separate impact on the thickness estimate in the dependence of an individual input variable as mentioned above. The results show systematic bias of the estimated ice thickness appears to be mainly caused by the variations of freeboard as well as the ice density whereas the snow density and depth brings about relatively insignificant errors. [ABSTRACT FROM AUTHOR]