finally to the poor performance of Li-S batteries. [1][2][3][4][5][6][7][8][9][10] The state-of-the-art separators used in Li-S batteries are commonly porous polypropylene (PP) films, but their pores are too large to restrict polysulfide shuttling (Figure 1a). Lots of efforts have been made to mitigate this shuttle effect by physical repulsion or chemical adsorption routes such as filling or covering the pores with polymers, [11][12][13][14] metal-organic frameworks (MOFs), [15] metal oxides, [16,17] graphene, [18][19][20] modified carbon nanotubes, [21,22] etc. (Figure 1b). Unfortunately, the filled or covered pores also restrict the transportation of Li + ions, increase the inner resistance, and finally deteriorate the performance of Li-S batteries.In this report, we propose a new strategy to selectively coordinate high-order polysulfides with "tertiary amine layer (TAL)" by which to simultaneously keep the pores of the separator still open to lithium ion's transportation. The construction of the polysulfide tongs is based on the classic "soft and hard acid-base (SHAB) theory." Different from the literature chemical interaction strategies, the anchoring groups to trap polysulfide are chemically grafted onto the PP separator, which is tough and stable. Also, the dissolved high-order Li 2 S x (x = 4, 6, and 8) can be more efficiently grasped when they try to diffuse across the narrowed but opening complex pores (Figure 1c). Li 2 S x species are relatively "soft" acids as the positive charges are mainly dispersed on the surface of the agglomerated polysulfide mole cules. Moreover, after the lithium ions are coordinated by sulfur, there are still "electron cloud holes" in Li 2 S x molecules to accept electrons from other molecules ( Figure S2, Supporting Information). In this regard, if we construct a "soft" base on the separator, the high-order Li 2 S x (x = 4, 6, and 8) soft acid can be grasped when they are further reduced and released in the cathode. On the contrary, lithium ion, which is commonly recognized as "hard" acid because of its small size and concentrated charge density, will be repulsed away by the "soft" base on the separator according to the SHAB theory. The chosen "soft" base for grasping polysulfide tong is tertiary amine (TA) group, which has a dispersed electron cloud and large head volume. TA group do not possess N-hydrogen atom, so we do not need to worry about the potential side reactions between active hydrogen and lithium-related compounds. Also, because the largest binding energy (E b ) between Li 2 S x Rechargeable lithium-sulfur batteries, which use sulfur as the cathode material, promise great potentials to be the next-generation high-energy system. However, higher-order lithium polysulfides, Li 2 S x (x = 4, 6, and 8), regardless of in charge or in discharge, always form first, dissolve subsequently in the electrolyte, and shuttle to the cathode and the anode, which is called "shuttle effect." The polysulfides shuttle effect leads to heavy loss of the active-sulfur materials. Literatu...

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MODIS time series data have been widely used in the research of regional and global ecosystems and climate change. For vegetation monitoring, vegetation indices such as NDVI (normalized difference vegetation index), EVI (enhanced vegetation index) and NBR (normalized burn ratio), are usually derived from MODIS reflectance data. However, noise usually makes it difficult to generate reliable time series of vegetation indices. Although some methods have been developed for reconstructing NDVI time series data, they still suffer from some limitations. First, there is no reliable approach for detecting and dealing with low-quality data, resulting in poor outcomes. Second, no effective evaluation of the fidelity of the corrected data to the original data has been discussed. For these reasons, we developed a new time series reconstruction approach, named Fixing Invalid Value (FIV) method. The proposed method assumes that the noise in surface reflectance data stems from invalid data, such as clouds, ice, and missing values. The FIV method first uses the spatially and temporally neighboring pixels to estimate the invalid values and then applies morphology operations to remove the residual noise. Finally, the Savitzky-Golay (S-G) filter is employed to generate the final results. The FIV method is tested on 8-day composite MODIS surface reflectance time series data from 2001 to 2012 in Jiangxi and Fujian provinces, China. The results show that the FIV method outperforms the conventional S-G filter and the HANTS method both in terms of visual inspection and quantitative evaluation. Furthermore, the fidelity evaluation reveals that the proposed FIV method produces high-quality time series data under all weather conditions. INDEX TERMS Time series reconstruction, removal of noise, Savitzky-Golay filtering, NDVI, MODIS.

Deforestation-induced landscape fragmentation causes habitat loss and isolation, modifies local climate, and therefore threatens biodiversity. While, on the contrary, how large-scale reforestation may improve the connectivity and thermal buffers of habitats is not well understood. We show that decades long large-scale reforestation in China has effectively increased the size and connectivity of forest patches by gradually filling gaps among isolated patches and creating more core forests. The core forests have a stronger capacity to cool the land surface, leading to a daily mean cooling effect of -0.42±0.23°C relative to nearby marginal forests. Moreover, the core forests reduce diurnal range and seasonal variation of land surface temperature by 1.41±0.23°C and 0.42±0.55°C, respectively, relative to nearby marginal forests. The thermal buffering capacity of large size core forest (>100km2) is more than twice that of small size (≤10km2). Despite their relatively low thermal buffering capacity, the marginal forests contribute about 73% to the increase of forest area in China during the last two decades and create buffer zones for the core forests to resist external disturbances, maintaining the internal stability of the forest ecosystem. We highlight that improving the integrity and connectivity of the forests with ecological restoration and succession can further enhance potential of forests to buffer local thermal environment under the current reforestation efforts, and thereby providing better connected thermal habitats for species to survive under climate change.